Digitala Vetenskapliga Arkivet

Change search
Refine search result
1 - 43 of 43
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Boon, Hanneke
    et al.
    Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.
    Sjögren, Rasmus J.O.
    Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.
    Massart, Julie
    Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.
    Egan, Brendan
    Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.
    Kostovski, Emil
    Section for Spinal Cord Injury, Sunnaas Rehabilitation Hospital, Nesoddtangen, Norway; Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway & Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
    Iversen, Per Ole
    Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway & Department of Hematology, Oslo University Hospital, Oslo, Norway.
    Hjeltnes, Nils
    Section for Spinal Cord Injury, Sunnaas Rehabilitation Hospital, Nesoddtangen, Norway.
    Chibalin, Alexander V
    Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.
    Widegren, Ulrika
    Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.
    Zierath, Juleen R.
    Department of Molecular Medicine and Surgery, Section for Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.
    MicroRNA-208b progressively declines after spinal cord injury in humans and is inversely related to myostatin expression2015In: Physiological Reports, E-ISSN 2051-817X, Vol. 3, no 11, article id e12622Article in journal (Refereed)
    Abstract [en]

    The effects of long‐term physical inactivity on the expression of microRNAs involved in the regulation of skeletal muscle mass in humans are largely unknown. MicroRNAs are short, noncoding RNAs that fine‐tune target expression through mRNA degradation or by inhibiting protein translation. Intronic to the slow, type I, muscle fiber type genes MYH7 and MYH7b, microRNA‐208b and microRNA‐499‐5p are thought to fine‐tune the expression of genes important for muscle growth, such as myostatin. Spinal cord injured humans are characterized by both skeletal muscle atrophy and transformation toward fast‐twitch, type II fibers. We determined the expression of microRNA‐208b, microRNA‐499‐5p, and myostatin in human skeletal muscle after complete cervical spinal cord injury. We also determined whether these microRNAs altered myostatin expression in rodent skeletal muscle. A progressive decline in skeletal muscle microRNA‐208b and microRNA‐499‐5p expression occurred in humans during the first year after spinal cord injury and with long‐standing spinal cord injury. Expression of myostatin was inversely correlated with microRNA‐208b and microRNA‐499‐5p in human skeletal muscle after spinal cord injury. Overexpression of microRNA‐208b in intact mouse skeletal muscle decreased myostatin expression, whereas microRNA‐499‐5p was without effect. In conclusion, we provide evidence for an inverse relationship between expression of microRNA‐208b and its previously validated target myostatin in humans with severe skeletal muscle atrophy. Moreover, we provide direct evidence that microRNA‐208b overexpression decreases myostatin gene expression in intact rodent muscle. Our results implicate that microRNA‐208b modulates myostatin expression and this may play a role in the regulation of skeletal muscle mass following spinal cord injury. © 2015 The Authors

  • 2.
    Cardinale, Daniele A
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Research group for Mitokondriell funktion och metabolisk kontroll. Elite Performance Centre, Bosön.
    Gejl, Kasper D
    University of Southern Denmark.
    Ørtenblad, Niels
    University of Southern Denmark.
    Ekblom, Bjorn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's research group.
    Blomstrand, Eva
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Eva Blomstrand's research group.
    Larsen, Filip J
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Research group for Mitokondriell funktion och metabolisk kontroll.
    Reliability of maximal mitochondrial oxidative phosphorylation in permeabilized fibers from the vastus lateralis employing high-resolution respirometry.2018In: Physiological Reports, E-ISSN 2051-817X, Vol. 6, no 4, article id e13611Article in journal (Refereed)
    Abstract [en]

    The purpose was to assess the impact of various factors on methodological errors associated with measurement of maximal oxidative phosphorylation (OXPHOS) in human skeletal muscle determined by high-resolution respirometry in saponin-permeabilized fibers. Biopsies were collected from 25 men to assess differences in OXPHOS between two muscle bundles and to assess the correlation between OXPHOS and the wet weight of the muscle bundle. Biopsies from left and right thighs of another five subjects were collected on two occasions to compare limbs and time-points. A single muscle specimen was used to assess effects of the anesthetic carbocaine and the influence of technician. The difference in OXPHOS between two fiber-bundles from the same biopsy exhibited a standard error of measurement (SEM) of 10.5 pmol · s-1  · mg-1 and a coefficient of variation (CV) of 15.2%. The differences between left and right thighs and between two different time-points had SEMs of 9.4 and 15.2 pmol · s-1  · mg-1 and CVs of 23.9% and 33.1%, respectively. The average (±SD) values obtained by two technicians monitoring different bundles of fibers from the same biopsy were 31.3 ± 7.1 and 26.3 ± 8.1 pmol · s-1  · mg-1 . The time that elapsed after collection of the biopsy (up to a least 5 h in preservation medium), wet weight of the bundle (from 0.5 to 4.5 mg) and presence of an anesthetic did not influence OXPHOS. The major source of variation in OXPHOS measurements is the sample preparation. The thigh involved, time-point of collection, size of fiber bundles, and time that elapsed after biopsy had minor or no effect.

  • 3.
    Carlén, Anna
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Åström Aneq, Meriam
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Gustafsson, Mikael
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    ST/HR variables in firefighter exercise ECG: relation to ischemic heart disease2019In: Physiological Reports, E-ISSN 2051-817X, Vol. 7, no 2, article id e13968Article in journal (Refereed)
    Abstract [en]

    Exercise electrocardiography (ExECG) is regularly performed by Swedish firefighters by law. Heart rate-corrected analysis of ST segment variables (ST/HR) has shown improved prediction of ischemic heart disease (IHD) compared to ST depression alone. This has not previously been extensively studied in asymptomatic persons with a low probability of IHD. We therefore evaluated the predictive performance of ST/HR analysis in firefighter ExECG. ExECG was studied in 521 male firefighters. During 8.4 ± 2.1 years, 2.3% (n = 12) were verified with IHD by catheterization or myocardial scintigraphy (age 51.5 ± 5.5 years) and were compared with firefighters without imaging proof of IHD (44.2 ± 10.1 years). The predictive value of ST depression, ST/HR index, ST/HR slope, and area and rotation of the ST/HR loop was calculated as age-adjusted odds ratios (OR), in 10 ECG leads. Predictive accuracy was analyzed with receiver operating characteristics (ROC) analysis. ST/HR index ≤-1.6 μV/bpm and ST/HR slope ≤-2.4 μV/bpm were associated with increased IHD risk in three individual leads (all OR > 1.0, P < 0.05). ST/HR loop area lower than the fifth percentile of non-IHD subjects indicated IHD risk in V4, V5, aVF, II, and -aVR (P < 0.05). ST depression ≤-0.1 mV was associated with IHD only in V4 (OR, 9.6, CI, 2.3-40.0). ROC analysis of each of these variables yielded areas under the curve of 0.72 or lower for all variables and leads. Clockwise-rotated ST/HR loops was associated with increased risk in most leads compared to counterclockwise rotation. The limited clinical value of ExECG in low-risk populations was emphasized, but if performed, ST/HR analysis should probably be given more importance.

    Download full text (pdf)
    fulltext
  • 4.
    Chaillou, Thomas
    et al.
    Örebro University, School of Health Sciences. Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
    McPeek, Ashley
    Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
    Lanner, Johanna T.
    Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
    Docetaxel does not impair skeletal muscle force production in a murine model of cancer chemotherapy2017In: Physiological Reports, E-ISSN 2051-817X, Vol. 5, no 11, article id e13261Article in journal (Refereed)
    Abstract [en]

    Chemotherapy drugs such as docetaxel are commonly used to treat cancer. Cancer patients treated with chemotherapy experience decreased physical fitness, muscle weakness and fatigue. To date, it is unclear whether these symptoms result only from cancer-derived factors or from the combination of cancer disease and cancer treatments, such as chemotherapy. In this study, we aimed at determining the impact of chemotherapy per se on force production of hind limb muscles from healthy mice treated with docetaxel. We hypothesized that docetaxel will decrease maximal force, exacerbate the force decline during repeated contractions and impair recovery after fatiguing stimulations. We examined the function of soleus and extensor digitorum longus (EDL) muscles 24h and 72h after a single injection of docetaxel (acute treatment), and 7days after the third weekly injection of docetaxel (repeated treatment). Docetaxel was administrated by intravenous injection (20mg/kg) in female FVB/NRj mice and control mice were injected with saline solution. Our results show that neither acute nor repeated docetaxel treatment significantly alters force production during maximal contractions, repeated contractions or recovery. Only a tendency to decreased peak specific force was observed in soleus muscles 24h after a single injection of docetaxel (-17%, P=0.13). In conclusion, docetaxel administered intravenously does not impair force production in hind limb muscles from healthy mice. It remains to be clarified whether docetaxel, or other chemotherapy drugs, affect muscle function in subjects with cancer and whether the side effects associated with chemotherapy (neurotoxicity, central fatigue, decreased physical activity, etc.) are responsible for the experienced muscle weakness and fatigue.

  • 5.
    Dahlberg, Pia
    et al.
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Cardiology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden.
    Axelsson, Karl-Jonas
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Cardiology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden.
    Jensen, Steen M.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine.
    Lundahl, Gunilla
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Vahedi, Farzad
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Cardiology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden.
    Perkins, Rosie
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Gransberg, Lennart
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Bergfeldt, Lennart
    Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Cardiology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden.
    Accelerated QT adaptation following atropine-induced heart rate increase in LQT1 patients versus healthy controls: a sign of disturbed hysteresis2022In: Physiological Reports, E-ISSN 2051-817X, Vol. 10, no 21, article id e15487Article in journal (Refereed)
    Abstract [en]

    Hysteresis, a ubiquitous regulatory phenomenon, is a salient feature of the adaptation of ventricular repolarization duration to heart rate (HR) change. We therefore compared the QT interval adaptation to rapid HR increase in patients with the long QT syndrome type 1 (LQT1) versus healthy controls because LQT1 is caused by loss-of-function mutations affecting the repolarizing potassium channel current IKs , presumably an important player in QT hysteresis. The study was performed in an outpatient hospital setting. HR was increased in LQT1 patients and controls by administering an intravenous bolus of atropine (0.04 mg/kg body weight) for 30 s. RR and QT intervals were recorded by continuous Frank vectorcardiography. Atropine induced transient expected side effects but no adverse arrhythmias. There was no difference in HR response (RR intervals) to atropine between the groups. Although atropine-induced ΔQT was 48% greater in 18 LQT1 patients than in 28 controls (p < 0.001), QT adaptation was on average 25% faster in LQT1 patients (measured as the time constant τ for the mono-exponential function and the time for 90% of ΔQT; p < 0.01); however, there was some overlap between the groups, possibly a beta-blocker effect. The shorter QT adaptation time to atropine-induced HR increase in LQT1 patients on the group level corroborates the importance of IKs in QT adaptation hysteresis in humans and shows that LQT1 patients have a disturbed ultra-rapid cardiac memory. On the individual level, the QT adaptation time possibly reflects the effect-size of the loss-of-function mutation, but its clinical implications need to be shown.

    Download full text (pdf)
    fulltext
  • 6.
    Emanuelsson, Eric B.
    et al.
    Karolinska Inst, Dept Physiol & Pharmacol, Stockholm, Sweden..
    Berry, David B.
    Univ Calif San Diego, Dept Nanoengn, La Jolla, CA 92093 USA.;Univ Calif San Diego, Dept Orthopaed Surg, La Jolla, CA 92093 USA.;Univ Calif San Diego, Dept Radiol, La Jolla, CA 92093 USA..
    Reitzner, Stefan M.
    Karolinska Inst, Dept Physiol & Pharmacol, Stockholm, Sweden.;Karolinska Inst, Dept Womens & Childrens Hlth, Stockholm, Sweden..
    Arif, Muhammad
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Systems Biology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Mardinoglu, Adil
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Systems Biology. Kings Coll London, Fac Dent Oral & Craniofacial Sci, Ctr Host Microbiome Interact, London, England..
    Gustafsson, Thomas
    Karolinska Inst, Dept Lab Med, Huddinge, Sweden.;Karolinska Univ Hosp, Unit Clin Physiol, Stockholm, Sweden..
    Ward, Samuel R.
    Univ Calif San Diego, Dept Orthopaed Surg, La Jolla, CA 92093 USA.;Univ Calif San Diego, Dept Radiol, La Jolla, CA 92093 USA.;Univ Calif San Diego, Dept Bioengn, La Jolla, CA 92093 USA..
    Sundberg, Carl Johan
    Karolinska Inst, Dept Physiol & Pharmacol, Stockholm, Sweden.;Karolinska Inst, Dept Lab Med, Huddinge, Sweden.;Karolinska Inst, Dept Learning Informat Management & Eth, Stockholm, Sweden..
    Chapman, Mark A.
    Karolinska Inst, Dept Physiol & Pharmacol, Stockholm, Sweden.;Univ San Diego, Dept Integrated Engn, 5998 Alcala Pk, San Diego, CA 92110 USA..
    MRI characterization of skeletal muscle size and fatty infiltration in long--term trained and untrained individuals2022In: Physiological Reports, E-ISSN 2051-817X, Vol. 10, no 14, article id e15398Article in journal (Refereed)
    Abstract [en]

    This study investigated body composition measures in highly trained and untrained individuals using whole--body magnetic resonance imaging (MRI). Additionally, correlations between these measures and skeletal muscle gene expression were performed. Thirty-six individuals were included: endurance-trained males (ME, n = 8) and females (FE, n = 7), strength-trained males (MS, n = 7), and untrained control males (MC, n = 8) and females (FC, n = 6). MRI scans were performed, and resting M. vastus lateralis (VL) biopsies were subjected to RNA sequencing. Liver fat fraction, visceral adipose tissue volume (VAT), total body fat, and total lean tissue were measured from MRI data. Additionally, cross-sectional area (CSA) and fat signal fraction (FSF) were calculated from Mm. pectoralis, M. erector spinae and M. multifidus combined, Mm. quadriceps, and Mm. triceps surae (TS). Liver fat fraction, VAT, and total body fat relative to body weight were lower in ME and FE compared with corresponding controls. MS had a larger CSA across all four muscle groups and lower FSF in all muscles apart from TS compared with MC. ME had a lower FSF across all muscle groups and a larger CSA in all muscles except TS than MC. FE athletes showed a higher CSA in Mm. pectoralis and Mm. quadriceps and a lower CSA in TS than FC with no CSA differences found in the back muscles investigated. Surprisingly, the only difference in FSF between FE and FC was found in Mm. pectoralis. Lastly, correlations between VL gene expression and VL CSA as well as FSF showed that genes positively correlated with CSA revealed an enrichment of the oxidative phosphorylation and thermogenesis pathways, while the genes positively correlated with FSF showed significant enrichment of the spliceosome pathway. Although limited differences were found with training in females, our study suggests that both regular endurance and resistance training are useful in maintaining muscle mass, reducing adipose tissue deposits, and reducing muscle fat content in males.

  • 7.
    Farooqi, Nighat
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Pulmonary Medicine.
    Slinde, Frode
    Håglin, Lena
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Sandström, Thomas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Pulmonary Medicine.
    Validation of SenseWear Armband and ActiHeart monitors for assessments of daily energy expenditure in free-living women with chronic obstructive pulmonary disease2013In: Physiological Reports, E-ISSN 2051-817X, Vol. 1, no 6, article id e00150Article in journal (Refereed)
    Abstract [en]

    To provide individually adapted nutritional support to patients with chronic obstructive pulmonary disease (COPD), objective and reliable methods must be used to assess patient energy requirements. The aim of this study was to validate the use of SenseWear Armband (SWA) and ActiHeart (AH) monitors for assessing total daily energy expenditure (TEE) and activity energy expenditure (AEE) and compare these techniques with the doubly labeled water (DLW) method in free‐living women with COPD. TEE and AEE were measured in 19 women with COPD for 14 days using SWAs with software version 5.1 (TEESWA5, AEESWA5) or 6.1 (TEESWA6, AEESWA6) and AH monitors (TEEAH, AEEAH), using DLW (TEEDLW) as the criterion method. The three methods were compared using intraclass correlation coefficient (ICC) and Bland–Altman analyses. The mean TEE did not significantly differ between the DLW and SWA5.1 methods (−21 ± 726 kJ/day; P = 0.9), but it did significantly differ between the DLW and SWA6.1 (709 ± 667 kJ/day) (P < 0.001) and the DLW and AH methods (709 ± 786 kJ/day) (P < 0.001). Strong agreement was observed between the DLW and TEESWA5 methods (ICC = 0.76; 95% CI 0.47–0.90), with moderate agreements between the DLW and TEESWA6 (ICC = 0.66; 95% CI 0.02–0.88) and the DLW and TEEAH methods (ICC = 0.61; 95% CI 0.05–0.85). Compared with the DLW method, the SWA5.1 underestimated AEE by 12% (P = 0.03), whereas the SWA6.1 and AH monitors underestimated AEE by 35% (P < 0.001). Bland–Altman plots revealed no systematic bias for TEE or AEE. The SWA5.1 can reliably assess TEE in women with COPD. However, the SWA6.1 and AH monitors underestimate TEE. The SWA and AH monitors underestimate AEE.

    Download full text (pdf)
    fulltext
  • 8.
    Fegraeus, Kim Jaederkvist
    et al.
    Swedish Univ Agr Sci, Dept Anim Breeding & Genet, Uppsala, Sweden.
    Velie, Brandon D.
    Swedish Univ Agr Sci, Dept Anim Breeding & Genet, Uppsala, Sweden.
    Axelsson, Jeanette
    Swedish Univ Agr Sci, Dept Anim Breeding & Genet, Uppsala, Sweden.
    Ang, Rachel
    Univ Sydney, Fac Sci, Sydney, NSW, Australia.
    Hamilton, Natasha A.
    Univ Sydney, Fac Sci, Sydney, NSW, Australia.
    Andersson, Leif
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Uppsala University, Science for Life Laboratory, SciLifeLab. Swedish Univ Agr Sci, Dept Anim Breeding & Genet, Uppsala, Sweden; Texas A&M Univ, Dept Vet Integrat Biosci, College Stn, TX USA.
    Meadows, Jennifer R. S.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Lindgren, Gabriella
    Swedish Univ Agr Sci, Dept Anim Breeding & Genet, Uppsala, Sweden.
    A potential regulatory region near the EDN3 gene may control both harness racing performance and coat color variation in horses2018In: Physiological Reports, E-ISSN 2051-817X, Vol. 6, no 10, article id e13700Article in journal (Refereed)
    Abstract [en]

    The Swedish‐Norwegian Coldblooded trotter and the heavier North‐Swedish draught horse both descend from the North‐Swedish horse, but the Coldblooded trotters have been selected for racing performance while the North‐Swedish draught horse is mainly used for agricultural and forestry work. By comparing the genomes of Coldblooded trotters, North‐Swedish draught horses and Standardbreds for a large number of single‐nucleotide polymorphisms (SNPs), the aim of the study was to identify genetic regions that may be under selection for racing performance. We hypothesized that the selection for racing performance, in combination with unauthorized crossbreeding of Coldblooded trotters and Standardbreds, has created regions in the genome where the Coldblooded trotters and Standardbreds are similar, but differ from the North‐Swedish draught horse. A fixation index (Fst) analysis was performed and sliding window Delta Fst values were calculated across the three breeds. Five windows, where the average Fst between Coldblooded trotters and Standardbreds was low and the average Fst between Coldblooded trotters and North‐Swedish draught horses was high, were selected for further investigation. Associations between the most highly ranked SNPs and harness racing performance were analyzed in 400 raced Coldblooded trotters with race records. One SNP showed a significant association with racing performance, with the CC genotype appearing to be negatively associated. The SNP identified was genotyped in 1915 horses of 18 different breeds. The frequency of the TT genotype was high in breeds typically used for racing and show jumping while the frequency of the CC genotype was high in most pony breeds and draught horses. The closest gene in this region was the Endothelin3 gene (EDN3), a gene mainly involved in melanocyte and enteric neuron development. Both functional genetic and physiological studies are needed to fully understand the possible impacts of the gene on racing performance.

    Download full text (pdf)
    fulltext
  • 9.
    Gao, Xiang
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Lindqvist, Andreas
    Lund Univ, Diabet Ctr, Dept Clin Sci, Malmo, Sweden.
    Sandberg, Monica
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Groop, Leif
    Lund Univ, Diabet Ctr, Dept Clin Sci, Malmo, Sweden.
    Wierup, Nils
    Lund Univ, Diabet Ctr, Dept Clin Sci, Malmo, Sweden.
    Jansson, Leif
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Effects of GIP on regional blood flow during normoglycemia and hyperglycemia in anesthetized rats2018In: Physiological Reports, E-ISSN 2051-817X, Vol. 6, no 8, article id e13685Article in journal (Refereed)
    Abstract [en]

    The incretin hormone glucose-dependent insulinotropic polypeptide (GIP) potentiates glucose-stimulated insulin secretion, and affects -cell turnover. This study aimed at evaluating if some of the beneficial effects of GIP on glucose homeostasis can be explained by modulation of islet blood flow. Anesthetized Sprague-Dawley rats were infused intravenously with different doses of GIP (10, 20, or 60ng/kg*min) for 30min. Subsequent organ blood flow measurements were performed with microspheres. In separate animals, islets were perfused exvivo with GIP (10(-6)-10(-12)mol/L) during normo- and hyperglycemia and arteriolar responsiveness was recorded. The highest dose of GIP potentiated insulin secretion during hyperglycemia, but had no effect in normoglycemic rats. The highest GIP concentration decreased blood perfusion of whole pancreas, pancreatic islets, duodenum, colon, liver and kidneys. The decrease in blood flow was unaffected by ganglion blockade or adenosine receptor inhibition. In contrast to this, in single perfused islets GIP induced a dose-dependent arteriolar dilation. Thus, high doses of GIP exert a direct dilatory effect on islet arterioles in isolated islets, but induce a generalized vasoconstriction in splanchnic organs, including the whole pancreas and islets, invivo. The latter effect is unlikely to be mediated by adenosine, the autonomic nervous system, or endothelial mediators.

    Download full text (pdf)
    fulltext
  • 10.
    Gejl, Kasper D.
    et al.
    Univ Southern Denmark, Odense, Denmark.
    Vissing, Kristian
    Aarhus Univ, Aarhus, Denmark.
    Hansen, Mette
    Aarhus Univ, Aarhus, Denmark.
    Thams, Line
    Univ Southern Denmark, Odense, Denmark.
    Rokkedal-Lausch, Torben
    Aalborg Univ, Aalborg, Denmark.
    Plomgaard, Peter
    Rigshosp, Copenhagen, Denmark; Univ Copenhagen, Rigshosp, Copenhagen, Denmark.
    Lundby, Anne-Kristine Meinild
    Univ Copenhagen, Rigshosp, Copenhagen, Denmark.
    Nybo, Lars
    Univ Copenhagen, Copenhagen, Denmark.
    Jensen, Kurt
    Univ Southern Denmark, Odense, Denmark.
    Holmberg, Hans-Christer
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences. Swedish Olymp Comm, Stockholm.
    Ørtenblad, Niels
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences. Univ Southern Denmark, Odense, Denmark .
    Changes in metabolism but not myocellular signaling by training with CHO-restriction in endurance athletes2018In: Physiological Reports, E-ISSN 2051-817X, Vol. 6, no 17, article id e13847Article in journal (Refereed)
    Abstract [en]

    Carbohydrate (CHO) restricted training has been shown to increase the acute training response, whereas less is known about the acute effects after repeated CHO restricted training. On two occasions, the acute responses to CHO restriction were examined in endurance athletes. Study 1 examined cellular signaling and metabolic responses after seven training-days including CHO manipulation (n = 16). The protocol consisted of 1 h high-intensity cycling, followed by 7 h recovery, and 2 h of moderate-intensity exercise (120SS). Athletes were randomly assigned to low (LCHO: 80 g) or high (HCHO: 415 g) CHO during recovery and the 120SS. Study 2 examined unaccustomed exposure to the same training protocol (n = 12). In Study 1, muscle biopsies were obtained at rest and 1 h after 120SS, and blood samples drawn during the 120SS. In Study 2, substrate oxidation and plasma glucagon were determined. In Study 1, plasma insulin and proinsulin C-peptide were higher during the 120SS in HCHO compared to LCHO (insulin: 0 min: +37%; 60 min: +135%; 120 min: +357%, P = 0.05; proinsulin C-peptide: 0 min: +32%; 60 min: +52%; 120 min: +79%, P = 0.02), whereas plasma cholesterol was higher in LCHO (+15-17%, P = 0.03). Myocellular signaling did not differ between groups. p-AMPK and p-ACC were increased after 120SS (+35%, P = 0.03; +59%, P = 0.0004, respectively), with no alterations in p-p38, p-53, or p-CREB. In Study 2, glucagon and fat oxidation were higher in LCHO compared to HCHO during the 120SS (+26-40%, P = 0.03; +44-76%, P = 0.01 respectively). In conclusion, the clear respiratory and hematological effects of CHO restricted training were not translated into superior myocellular signaling after accustomization to CHO restriction.

    Download full text (pdf)
    fulltext
  • 11.
    Gejl, Kasper D.
    et al.
    Univ Southern Denmark, Odense, Denmark.
    Vissing, Kristian
    Aarhus Univ, Aarhus, Denmark.
    Hansen, Mette
    Aarhus Univ, Aarhus, Denmark.
    Thams, Line
    Univ Southern Denmark, Odense, Denmark.
    Rokkedal-Lausch, Torben
    Aalborg Univ, Aalborg, Denmark.
    Plomgaard, Peter
    Rigshosp, Copenhagen, Denmark; Univ Copenhagen, Rigshosp, Copenhagen, Denmark.
    Lundby, Anne-Kristine Meinild
    Univ Copenhagen, Rigshosp, Copenhagen, Denmark.
    Nybo, Lars
    Univ Copenhagen, Copenhagen, Denmark.
    Jensen, Kurt
    Univ Southern Denmark, Odense, Denmark.
    Holmberg, Hans-Christer
    Mittuniversitetet, Avdelningen för hälsovetenskap.
    Ørtenblad, Niels
    Mittuniversitetet, Avdelningen för hälsovetenskap.
    Changes in metabolism but not myocellular signaling by training with CHO-restriction in endurance athletes2018In: Physiological Reports, E-ISSN 2051-817X, Vol. 6, no 17, article id e13847Article in journal (Refereed)
    Abstract [en]

    Carbohydrate (CHO) restricted training has been shown to increase the acute training response, whereas less is known about the acute effects after repeated CHO restricted training. On two occasions, the acute responses to CHO restriction were examined in endurance athletes. Study 1 examined cellular signaling and metabolic responses after seven training-days including CHO manipulation (n = 16). The protocol consisted of 1 h high-intensity cycling, followed by 7 h recovery, and 2 h of moderate-intensity exercise (120SS). Athletes were randomly assigned to low (LCHO: 80 g) or high (HCHO: 415 g) CHO during recovery and the 120SS. Study 2 examined unaccustomed exposure to the same training protocol (n = 12). In Study 1, muscle biopsies were obtained at rest and 1 h after 120SS, and blood samples drawn during the 120SS. In Study 2, substrate oxidation and plasma glucagon were determined. In Study 1, plasma insulin and proinsulin C-peptide were higher during the 120SS in HCHO compared to LCHO (insulin: 0 min: +37%; 60 min: +135%; 120 min: +357%, P = 0.05; proinsulin C-peptide: 0 min: +32%; 60 min: +52%; 120 min: +79%, P = 0.02), whereas plasma cholesterol was higher in LCHO (+15-17%, P = 0.03). Myocellular signaling did not differ between groups. p-AMPK and p-ACC were increased after 120SS (+35%, P = 0.03; +59%, P = 0.0004, respectively), with no alterations in p-p38, p-53, or p-CREB. In Study 2, glucagon and fat oxidation were higher in LCHO compared to HCHO during the 120SS (+26-40%, P = 0.03; +44-76%, P = 0.01 respectively). In conclusion, the clear respiratory and hematological effects of CHO restricted training were not translated into superior myocellular signaling after accustomization to CHO restriction.

  • 12.
    Gidlund, Eva-Karin
    et al.
    Karolinska Inst, Dept Physiol & Pharmacol, Von Eulers Vag 8, S-17177 Stockholm, Sweden..
    von Walden, Ferdinand
    Karolinska Inst, Dept Womens & Childrens Hlth, Neuropediat Unit, Stockholm, Sweden.;Astrid Lindgrens Pediat Hosp, Stockholm, Sweden..
    Venojarvi, Mika
    Univ Eastern Finland, Inst Biomed Sports & Exercise Med, Kuopio, Finland..
    Risérus, Ulf
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism.
    Heinonen, Olli J.
    Univ Turku, Paavo Nurmi Ctr, Turku, Finland.;Univ Turku, Dept Hlth & Phys Act, Turku, Finland..
    Norrbom, Jessica
    Karolinska Inst, Dept Physiol & Pharmacol, Von Eulers Vag 8, S-17177 Stockholm, Sweden..
    Sundberg, Carl Johan
    Karolinska Inst, Dept Physiol & Pharmacol, Von Eulers Vag 8, S-17177 Stockholm, Sweden..
    Humanin skeletal muscle protein levels increase after resistance training in men with impaired glucose metabolism2016In: Physiological Reports, E-ISSN 2051-817X, Vol. 4, no 23, article id e13063Article in journal (Refereed)
    Abstract [en]

    Humanin (HN) is a mitochondrially encoded and secreted peptide linked to glucose metabolism and tissue protecting mechanisms. Whether skeletal muscle HN gene or protein expression is influenced by exercise remains unknown. In this intervention study we show, for the first time, that HN protein levels increase in human skeletal muscle following 12 weeks of resistance training in persons with prediabetes. Male subjects (n = 55) with impaired glucose regulation (IGR) were recruited and randomly assigned to resistance training, Nordic walking or a control group. The exercise interventions were performed three times per week for 12 weeks with progressively increased intensity during the intervention period. Biopsies from the vastus lateralis muscle and venous blood samples were taken before and after the intervention. Skeletal muscle and serum protein levels of HN were analyzed as well as skeletal muscle gene expression of the mitochondrially encoded gene MT-RNR2, containing the open reading frame for HN. To elucidate mitochondrial training adaptation, mtDNA, and nuclear DNA as well as Citrate synthase were measured. Skeletal muscle HN protein levels increased by 35% after 12 weeks of resistance training. No change in humanin protein levels was seen in serum in any of the intervention groups. There was a significant correlation between humanin levels in serum and the improvements in the 2 h glucose loading test in the resistance training group. The increase in HN protein levels in skeletal muscle after regular resistance training in prediabetic males may suggest a role for HN in the regulation of glucose metabolism. Given the preventative effect of exercise on diabetes type 2, the role of HN as a mitochondrially derived peptide and an exercise-responsive mitokine warrants further investigation.

    Download full text (pdf)
    fulltext
  • 13.
    Gottlieb, Lisa A
    et al.
    Department of Cardiology, Copenhagen University Hospital - Bispebjerg, Copenhagen, Denmark; Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
    Evans, Alina L.
    Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Koppang, Norway.
    Fuchs, Boris
    Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Koppang, Norway.
    Fröbert, Ole
    Örebro University, School of Medical Sciences. Department of Cardiology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden; Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark; Department of Clinical Pharmacology, Aarhus University Hospital, Aarhus, Denmark.
    Björkenheim, Anna
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Cardiology.
    Translational implications of bradyarrhythmia in hibernating brown bears2023In: Physiological Reports, E-ISSN 2051-817X, Vol. 11, no 1, article id e15550Article in journal (Refereed)
    Abstract [en]

    The brown bear Ursus arctos undergoes exceptional physiological adaptions during annual hibernation that minimize energy consumption, including profound decrease in heart rate, cardiac output, and respiratory rate. These changes are completely reversible after the bears reenter into the active state in spring. In this case report, we show episodes of sinus arrest in a hibernating Scandinavian brown bear and in humans, recorded by implantable loop recorders and discuss the possible underlying mechanisms. Lessons learned from cardiac adaptations in hibernating bears might prove useful in the treatment of patients with sinus node dysfunction.

  • 14.
    Gouveia, Leonor
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Betsholtz, Christer
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology. Karolinska Inst, Integrated Cardio Metab Ctr, Huddinge, Sweden..
    Andrae, Johanna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Expression analysis of platelet-derived growth factor receptor alpha and its ligands in the developing mouse lung2017In: Physiological Reports, E-ISSN 2051-817X, Vol. 5, no 6, article id e13092Article in journal (Refereed)
    Abstract [en]

    Activation of the platelet-derived growth factor receptor-a (PDGFRa) signaling pathway is critically important during lung alveogenesis, the process in lung development during which alveoli are formed from the terminal alveolar sacs. Several studies have aimed to characterize the expression patterns of PDGFRa and its two ligands (PDGF-A and -C) in the lung, but published analyses have been limited to embryonic and/or perinatal time points, and no attempts have been made to characterize both receptor and ligand expression simultaneously. In this study, we present a detailed map of the expression patterns of PDGFRa, PDGF-A and PDGF-C during the entire period of lung development, that is, from early embryogenesis until adulthood. Three different reporter mice were analyzed (Pdgfa ex4-COIN-INV-lacZ, Pdgfc tm1Nagy, and Pdgfra tm11(EGFP) Sor), in which either lacZ or H2B-GFP were expressed under the respective promoter in gene-targeted alleles. A spatiotemporal dynamic expression was identified for both ligands and receptor. PDGF-A and PDGF-C were located to distinct populations of epithelial and smooth muscle cells, whereas PDGFRa expression was located to different mesenchymal cell populations. The detailed characterization of gene expression provides a comprehensive map of PDGFRa signaling in lung cells, opening up for a better understanding of the role of PDGF signaling during lung development.

    Download full text (pdf)
    fulltext
  • 15.
    He, Rebecca S. S.
    et al.
    Duke Univ, NC USA.
    De Ruiter, Stacy
    Calvin Univ, MI USA.
    Westover, Tristan
    Duke Univ, NC USA.
    Somarelli, Jason A.
    Duke Univ, NC USA.
    Blawas, Ashley M.
    Duke Univ, NC USA.
    Dayanidhi, Divya L.
    Duke Univ, NC USA.
    Singh, Ana
    Calvin Univ, MI USA.
    Steves, Benjamin
    Calvin Univ, MI USA.
    Driesinga, Samantha
    Calvin Univ, MI USA.
    Halsey, Lewis G.
    Univ Roehampton, England.
    Fahlman, Andreas
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. Fdn Oceanog Comunitat Valenciana, Spain; Kolmarden Wildlife Pk, Sweden.
    Allometric scaling of metabolic rate and cardiorespiratory variables in aquatic and terrestrial mammals2023In: Physiological Reports, E-ISSN 2051-817X, Vol. 11, no 11, article id e15698Article in journal (Refereed)
    Abstract [en]

    While basal metabolic rate (BMR) scales proportionally with body mass (M-b), it remains unclear whether the relationship differs between mammals from aquatic and terrestrial habitats. We hypothesized that differences in BMR allometry would be reflected in similar differences in scaling of O-2 delivery pathways through the cardiorespiratory system. We performed a comparative analysis of BMR across 63 mammalian species (20 aquatic, 43 terrestrial) with a M-b range from 10 kg to 5318 kg. Our results revealed elevated BMRs in small (&gt;10 kg and &lt;100 kg) aquatic mammals compared to small terrestrial mammals. The results demonstrated that minute ventilation, that is, tidal volume (V-T)center dot breathing frequency (f(R)), as well as cardiac output, that is, stroke volume center dot heart rate, do not differ between the two habitats. We found that the "aquatic breathing strategy", characterized by higher V-T and lower f(R) resulting in a more effective gas exchange, and by elevated blood hemoglobin concentrations resulting in a higher volume of O-2 for the same volume of blood, supported elevated metabolic requirements in aquatic mammals. The results from this study provide a possible explanation of how differences in gas exchange may serve energy demands in aquatic versus terrestrial mammals.

    Download full text (pdf)
    fulltext
  • 16.
    Holm, Lars
    et al.
    Institute of Sports Medicine and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
    Dideriksen, Kasper
    Institute of Sports Medicine and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
    Nielsen, Rie H
    Institute of Sports Medicine and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
    Doessing, Simon
    Institute of Sports Medicine and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
    Bechshoeft, Rasmus L
    Institute of Sports Medicine and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
    Højfeldt, Grith
    Institute of Sports Medicine and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
    Moberg, Marcus
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Eva Blomstrand's research group.
    Blomstrand, Eva
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Eva Blomstrand's research group. Karolinska institutet.
    Reitelseder, Søren
    Institute of Sports Medicine and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
    van Hall, Gerrit
    University of Copenhagen, Denmark.
    An exploration of the methods to determine the protein-specific synthesis and breakdown rates in vivo in humans.2019In: Physiological Reports, E-ISSN 2051-817X, Vol. 7, no 17, article id e14143Article in journal (Refereed)
    Abstract [en]

    The present study explores the methods to determine human in vivo protein-specific myofibrillar and collagenous connective tissue protein fractional synthesis and breakdown rates. We found that in human myofibrillar proteins, the protein-bound tracer disappearance method to determine the protein fractional breakdown rate (FBR) (via 2 H2 O ingestion, endogenous labeling of 2 H-alanine that is incorporated into proteins, and FBR quantified by its disappearance from these proteins) has a comparable intrasubject reproducibility (range: 0.09-53.5%) as the established direct-essential amino acid, here L-ring-13 C6 -phenylalanine, incorporation method to determine the muscle protein fractional synthesis rate (FSR) (range: 2.8-56.2%). Further, the determination of the protein breakdown in a protein structure with complex post-translational processing and maturation, exemplified by human tendon tissue, was not achieved in this experimentation, but more investigation is encouraged to reveal the possibility. Finally, we found that muscle protein FBR measured with an essential amino acid tracer prelabeling is inappropriate presumably because of significant and prolonged intracellular recycling, which also may become a significant limitation for determination of the myofibrillar FSR when repeated infusion trials are completed in the same participants.

    Download full text (pdf)
    fulltext
  • 17.
    Holmberg, Ellinor
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynecology.
    Johansson, Maja
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynecology.
    Bäckström, Torbjörn
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynecology.
    Haage, David
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynecology.
    Allopregnanolone preferentially induces energy-rich food intake in male Wistar rats2014In: Physiological Reports, E-ISSN 2051-817X, Vol. 2, no 12, p. e12190-Article in journal (Refereed)
    Abstract [en]

    Obesity is an increasing problem and identification of the driving forces for overeating of energy-rich food is important. Previous studies show that the stress and sex steroid allopregnanolone has a hyperphagic effect on both bland food and palatable food. If allopregnanolone induces a preference for more palatable or for more energy-rich food is not known. The aim of this study  was to elucidate the influence of allopregnanolone on food preference. Male Wistar rats were subjected to two different food preference tests: a choice between standard chow and cookies (which have a higher energy content and also are more palatable than chow), and a choice between a low caloric sucrose solution and standard chow (which has a higher energy content and is less palatable than sucrose). Food intake was measured for 1 h after acute subcutaneous injections of allopregnanolone. In the choice between cookies and chow allopregnanolone significantly increased only the intake of cookies.When the standard chow was the item present with the highest caloric load, the chow intake was increased and allopregnanolone had no effect on intake of the 10% sucrose solution. The increased energy intakes induced by the high allopregnanolone dose compared to vehicle were very similar in the two tests,120% increase for cookies and 150% increase for chow. It appears that in allopregnanolone-induced hyperphagia, rats choose the food with the highest energy content regardless of its palatability.

    Download full text (pdf)
    fulltext
  • 18.
    Hultström, Michael
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology, Integrative Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala Univ, Dept Med Cell Biol, Integrat Physiol, Uppsala, Sweden.;Uppsala Univ, Dept Surg Sci Anesthesia & Intens Care Med, Uppsala, Sweden..
    Peng, Di
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Becirovic Agic, Mediha
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology, Integrative Physiology.
    Cupples, Claire G.
    Simon Fraser Univ, Dept Mol Biol & Biochem, Burnaby, BC, Canada..
    Cupples, William A.
    Simon Fraser Univ, Dept Biomed Physiol & Kinesiol, Burnaby, BC, Canada..
    Mitrou, Nicholas
    Simon Fraser Univ, Dept Biomed Physiol & Kinesiol, Burnaby, BC, Canada.;Univ Western Ontario, Dept Surg, London, ON, Canada..
    Surgical trauma is associated with renal immune cell activation in rats: A microarray study2021In: Physiological Reports, E-ISSN 2051-817X, Vol. 9, no 23, article id e15142Article in journal (Refereed)
    Abstract [en]

    Acute kidney injury (AKI) is a common perioperative complication that is associated with increased mortality. This study investigates the renal gene expression in male Long-Evans rats after prolonged anesthesia and surgery to detect molecular mechanisms that could predispose the kidneys to injury upon further insults. Healthy and streptozotocin diabetic rats that underwent autoregulatory investigation in an earlier study were compared to rats that were sacrificed quickly for mRNA quantification in the same study. Prolonged surgery caused massive changes in renal mRNA expression by microarray analysis, which was validated by quantitative real-time PCR with good correlation. Furthermore, bioinformatics analysis using gene ontology and pathway analysis identified biological processes involved in immune system activation, such as immune system processes (p = 1.3 x 10(-80)), immune response (p = 1.3 x 1(-60)), and regulation of cytokine production (p = 1.7 x 10(-52)). PCR analysis of specific cell type markers indicated that the gene activation in kidneys was most probably macrophages, while granulocytes and T cell appeared less activated. Immunohistochemistry was used to quantify immune cell infiltration and showed no difference between groups indicating that the genetic activation depends on the activation of resident cells, or infiltration of a relatively small number of highly activated cells. In follow-up experiments, surgery was performed on healthy rats under standard and sterile condition showing similar expression of immune cell markers, which suggests that the inflammation was indeed caused by the surgical trauma rather than by bacterial infection. In conclusion, surgical trauma is associated with rapid activation of immune cells, most likely macrophages in rat kidneys.

  • 19.
    Iresjö, Britt‐Marie
    et al.
    Department of Surgery, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden..
    Wang, Wenhua
    Department of Surgery, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden..
    Nilsberth, Camilla
    Region Östergötland, Local Health Care Services in Central Östergötland, Department of Geriatric Medicine in Linköping. Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Andersson, Marianne
    Department of Surgery, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden..
    Lönnroth, Christina
    Department of Surgery, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden..
    Smedh, Ulrika
    Department of Surgery, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden..
    Food intake, tumor growth, and weight loss in EP2 receptor subtype knockout mice bearing PGE2-producing tumors2015In: Physiological Reports, E-ISSN 2051-817X, ISSN 2051-817X, Vol. 3, no 7, p. 1-7, article id e12441Article in journal (Refereed)
    Abstract [en]

    Previous studies in our laboratory have demonstrated that prostaglandin (PG) E2 is involved in anorexia/cachexia development in MCG 101 tumor‐bearing mice. In the present study, we investigate the role of PGE receptor subtype EP2 in the development of anorexia after MCG 101 implantation in wild‐type (EP2+/+) or EP2‐receptor knockout (EP2−/−) mice. Our results showed that host absence of EP2 receptors attenuated tumor growth and development of anorexia in tumor‐bearing EP2 knockout mice compared to tumor‐bearing wild‐type animals. Microarray profiling of the hypothalamus revealed a relative twofold change in expression of around 35 genes including mRNA transcripts coding for Phospholipase A2 and Prostaglandin D2 synthase (Ptgds) in EP2 receptor knockout mice compared to wild‐type mice. Prostaglandin D2 synthase levels were increased significantly in EP2 receptor knockouts, suggesting that improved food intake may depend on altered balance of prostaglandin production in hypothalamus since PGE2 and PGD2 display opposing effects in feeding control.

    Download full text (pdf)
    fulltext
  • 20. Jensen, Line
    et al.
    Gejl, Kasper D
    Ørtenblad, Niels
    Nielsen, Jakob L
    Bech, Rune D
    Nygaard, Tobias
    Sahlin, Kent
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Research group for Mitokondriell funktion och metabolisk kontroll.
    Frandsen, Ulrik
    Carbohydrate restricted recovery from long term endurance exercise does not affect gene responses involved in mitochondrial biogenesis in highly trained athletes.2015In: Physiological Reports, E-ISSN 2051-817X, Vol. 3, no 2Article in journal (Refereed)
    Abstract [en]

    The aim was to determine if the metabolic adaptations, particularly PGC-1α and downstream metabolic genes were affected by restricting CHO following an endurance exercise bout in trained endurance athletes. A second aim was to compare baseline expression level of these genes to untrained. Elite endurance athletes (VO2max 66 ± 2 mL·kg(-1)·min(-1), n = 15) completed 4 h cycling at ~56% VO2max. During the first 4 h recovery subjects were provided with either CHO or only H2O and thereafter both groups received CHO. Muscle biopsies were collected before, after, and 4 and 24 h after exercise. Also, resting biopsies were collected from untrained subjects (n = 8). Exercise decreased glycogen by 67.7 ± 4.0% (from 699 ± 26.1 to 239 ± 29.5 mmol·kg(-1)·dw(-1)) with no difference between groups. Whereas 4 h of recovery with CHO partly replenished glycogen, the H2O group remained at post exercise level; nevertheless, the gene expression was not different between groups. Glycogen and most gene expression levels returned to baseline by 24 h in both CHO and H2O. Baseline mRNA expression of NRF-1, COX-IV, GLUT4 and PPAR-α gene targets were higher in trained compared to untrained. Additionally, the proportion of type I muscle fibers positively correlated with baseline mRNA for PGC-1α, TFAM, NRF-1, COX-IV, PPAR-α, and GLUT4 for both trained and untrained. CHO restriction during recovery from glycogen depleting exercise does not improve the mRNA response of markers of mitochondrial biogenesis. Further, baseline gene expression of key metabolic pathways is higher in trained than untrained.

    Download full text (pdf)
    fulltext
  • 21.
    Jensen, Line
    et al.
    University of Southern Denmark, Odense, Denmark.
    Gejl, Kasper D.
    University of Southern Denmark, Odense, Denmark.
    Ørtenblad, Niels
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences. University of Southern Denmark, Odense, Denmark.
    Nielsen, Jakob L.
    University of Southern Denmark, Odense, Denmark.
    Bech, Rune D.
    Department of Orthopedic Surgery, Odense University Hospital, Odense, Denmark.
    Nygaard, Tobias
    Department of Orthopedic Surgery, Rigshospitalet, Copenhagen, Denmark.
    Sahlin, Kent
    The Swedish School of Sport and Health Sciences, Stockholm.
    Frandsen, Ulrik
    University of Southern Denmark, Odense, Denmark.
    Carbohydrate restricted recovery from long term endurance exercise does not affect gene responses involved in mitochondrial biogenesis in highly trained athletes2015In: Physiological Reports, E-ISSN 2051-817X, Vol. 3, no 2, article id e12184Article in journal (Refereed)
    Abstract [en]

    The aim was to determine if the metabolic adaptations, particularly PGC-1a and downstream metabolic genes were affected by restricting CHO following an endurance exercise bout in trained endurance athletes. A second aim was to compare baseline expression level of these genes to untrained. Elite endurance athletes (VO2max 66 ± 2 mL·kg-1·min-1, n = 15) completed 4 h cycling at ~56% VO2max. During the first 4 h recovery subjects were provided with either CHO or only H2O and thereafter both groups received CHO. Muscle biopsies were collected before, after, and 4 and 24 h after exercise. Also, resting biopsies were collected from untrained subjects (n = 8). Exercise decreased glycogen by 67.7 ± 4.0% (from 699 ± 26.1 to 239 ± 29.5 mmol·kg-1·dw-1) with no difference between groups. Whereas 4 h of recovery with CHO partly replenished glycogen, the H2O group remained at post exercise level; nevertheless, the gene expression was not different between groups. Glycogen and most gene expression levels returned to baseline by 24 h in both CHO and H2O. Baseline mRNA expression of NRF-1, COX-IV, GLUT4 and PPAR-α gene targets were higher in trained compared to untrained. Additionally, the proportion of type I muscle fibers positively correlated with baseline mRNA for PGC-1α, TFAM, NRF-1, COX-IV, PPAR-α, and GLUT4 for both trained and untrained. CHO restriction during recovery from glycogen depleting exercise does not improve the mRNA response of markers of mitochondrial biogenesis. Further, baseline gene expression of key metabolic pathways is higher in trained than untrained.

    Download full text (pdf)
    fulltext
  • 22.
    Keramidas, Michail E.
    et al.
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Environmental Physiology. KTH, School of Technology and Health (STH), Centres, Swedish Aerospace Physiology Centre, SAPC.
    Mekjavic, Igor B.
    Kölegård, Roger
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Environmental Physiology. KTH, School of Technology and Health (STH), Centres, Swedish Aerospace Physiology Centre, SAPC.
    Chouker, Alexander
    Strewe, Claudia
    Eiken, Ola
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Environmental Physiology. KTH, School of Technology and Health (STH), Centres, Swedish Aerospace Physiology Centre, SAPC.
    PlanHab: Hypoxia counteracts the erythropoietin suppression, but seems to exaggerate the plasma volume reduction induced by 3 weeks of bed rest2016In: Physiological Reports, E-ISSN 2051-817X, Vol. 4, no 3Article in journal (Refereed)
    Abstract [en]

    The study examined the distinct and synergistic effects of hypoxia and bed rest on the erythropoietin (EPO) concentration and relative changes in plasma volume (PV). Eleven healthy male lowlanders underwent three 21‐day confinement periods, in a counterbalanced order: (1) normoxic bed rest (NBR; PIO2: 133.1 ± 0.3 mmHg); (2) hypoxic bed rest (HBR; PIO2: 90.0 ± 0.4 mmHg, ambient simulated altitude of ~4000 m); and (3) hypoxic ambulation (HAMB; PIO2: 90.0 ± 0.4 mmHg). Blood samples were collected before, during (days 2, 5, 14, and 21) and 2 days after each confinement to determine EPO concentration. Qualitative differences in PV changes were also estimated by changes in hematocrit and hemoglobin concentration along with concomitant changes in plasma renin concentration. NBR caused an initial reduction in EPO by ~39% (= 0.04). By contrast, HBR enhanced EPO (= 0.001), but the increase was less than that induced by HAMB (< 0.01). All three confinements caused a significant reduction in PV (< 0.05), with a substantially greater drop in HBR than in the other conditions (< 0.001). Thus, present results suggest that hypoxia prevents the EPO suppression, whereas it seems to exaggerate the PV reduction induced by bed rest.

  • 23.
    Kristenson, Karolina
    et al.
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, ANOPIVA US. Region Östergötland, Heart Center, Department of Thoracic and Vascular Surgery.
    Gerring, Edvard
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Clinical Physiology in Linköping.
    Björnsson, Bergthor
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Sandström, Per
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Hedman, Kristofer
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Clinical Physiology in Linköping.
    Peak oxygen uptake in combination with ventilatory efficiency improve risk stratification in major abdominal surgery2024In: Physiological Reports, E-ISSN 2051-817X, Vol. 12, no 1, article id e15904Article in journal (Refereed)
    Abstract [en]

    This pilot study aimed to evaluate if peak VO2 and ventilatory efficiency in combination would improve preoperative risk stratification beyond only relying on peak VO2. This was a single-center retrospective cohort study including all patients who underwent cardiopulmonary exercise testing (CPET) as part of preoperative risk evaluation before major upper abdominal surgery during years 2008-2021. The primary outcome was any major cardiopulmonary complication during hospitalization. Forty-nine patients had a preoperative CPET before decision to pursue to surgery (cancer in esophagus [n = 18], stomach [6], pancreas [16], or liver [9]). Twenty-five were selected for operation. Patients who suffered any major cardiopulmonary complication had lower ventilatory efficiency (i.e., higher VE/VCO2 slope, 37.3 vs. 29.7, p = 0.031) compared to those without complications. In patients with a low aerobic capacity (i.e., peak VO2 &lt; 20 mL/kg/min) and a VE/VCO2 slope &gt;= 39, 80% developed a major cardiopulmonary complication. In this pilot study of patients with preoperative CPET before major upper abdominal surgery, patients who experienced a major cardiopulmonary complication had significantly lower ventilatory efficiency compared to those who did not. A low aerobic capacity in combination with low ventilatory efficiency was associated with a very high risk (80%) of having a major cardiopulmonary complication.

  • 24.
    Krmar, Rafael T.
    et al.
    Karolinska Inst, Dept Physiol & Pharmacol, Stockholm, Sweden.;Karolinska Inst, Dept Physiol & Pharmacol, Biomed 5B,Solnavagen 9, SE-17177 Stockholm, Sweden..
    Franzén, Stephanie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Karlsson, Leif
    Karolinska Univ Hosp, Karolinska Inst, Dept Womens & Childrens Hlth, Pediat Endocrinol Unit, Stockholm, Sweden..
    Strandberg, Helin
    Lund Univ, Dept Biochem & Struct Biol, Lund, Sweden..
    Tornroth-Horsefield, Susanna
    Lund Univ, Dept Biochem & Struct Biol, Lund, Sweden..
    Andresen, Jesper K.
    Univ Southern Denmark, Inst Mol Med, Dept Cardiovasc & Renal Res, Odense, Denmark.;Odense Univ Hosp, Dept Urol, Odense, Denmark..
    Jensen, Boye L.
    Univ Southern Denmark, Inst Mol Med, Dept Cardiovasc & Renal Res, Odense, Denmark.;Odense Univ Hosp, Dept Urol, Odense, Denmark..
    Carlstrom, Mattias
    Karolinska Inst, Dept Physiol & Pharmacol, Stockholm, Sweden..
    Frithiof, Robert
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Effect of controlled hypotensive hemorrhage on plasma sodium levels in anesthetized pigs: An exploratory study2023In: Physiological Reports, E-ISSN 2051-817X, Vol. 11, no 22, article id e15886Article in journal (Refereed)
    Abstract [en]

    Perioperative hyponatremia, due to non-osmotic release of the antidiuretic hormone arginine vasopressin, is a serious electrolyte disorder observed in connection with many types of surgery. Since blood loss during surgery contributes to the pathogenesis of hyponatremia, we explored the effect of bleeding on plasma sodium using a controlled hypotensive hemorrhage pig model. After 30-min baseline period, hemorrhage was induced by aspiration of blood during 30 min at mean arterial pressure <50 mmHg. Thereafter, the animals were resuscitated with retransfused blood and a near-isotonic balanced crystalloid solution and monitored for 180 min. Electrolyte and water balances, cardiovascular response, renal hemodynamics, and markers of volume regulation and osmoregulation were investigated. All pigs (n = 10) developed hyponatremia. All animals retained hypotonic fluid, and none could excrete net-free water. Urinary excretion of aquaporin 2, a surrogate marker of collecting duct responsiveness to antidiuretic hormone, was significantly reduced at the end of the study, whereas lysine vasopressin, i.e., the pig antidiuretic hormone remained high. In this animal model, hyponatremia developed due to net positive fluid balance and generation of electrolyte-free water by the kidneys. A decreased urinary aquaporin 2 excretion may indicate an escape from antidiuresis.

    Download full text (pdf)
    fulltext
  • 25. Larsen, Steen
    et al.
    Scheede-Bergdahl, Celena
    Whitesell, Thomas
    Boushel, Robert
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Bergdahl, Andreas
    Increased intrinsic mitochondrial respiratory capacity in skeletal muscle from rats with streptozotocin-induced hyperglycemia.2015In: Physiological Reports, E-ISSN 2051-817X, Vol. 3, no 7, article id e12467Article in journal (Refereed)
    Abstract [en]

    Type I diabetes mellitus (T1DM) is a chronic disorder, characterized by an almost or complete insulin deficiency. Widespread tissue dysfunction and deleterious diabetes-complications are associated with long-term elevations of blood glucose. The aim of this study was to investigate the effects of type I diabetes, as induced by streptozotocin, on the mitochondria in skeletal muscles that predominantly consist of either slow or fast twitch fibers. Soleus (primarily slow twitch fiber type) and the plantaris muscle (mainly fast twitch fiber type) were removed in order to measure mitochondrial protein expression and integrated mitochondrial respiratory function. Mitochondrial capacity for oxidative phosphorylation (OXPHOS) was found to be higher in the slow (more oxidative) soleus muscle from STZ rats when evaluating lipid and complex I linked OXPHOS capacity, whereas no difference was detected between the groups when evaluating the more physiological complex I and II linked OXPHOS capacity. These findings indicate that chronic hyperglycemia results in an elevated intrinsic mitochondrial respiratory capacity in both soleus and, at varying degree, plantaris muscle, findings that are consistent with human T1DM patients.

  • 26.
    Laustsen, Christoffer
    et al.
    Department of Clinical Medicine, MR Research Centre, Aarhus University, Aarhus, Denmark.
    Lipsø, Kasper
    Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark Department of Electrical Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark.
    Ostergaard, Jakob Appel
    Department of Endocrinology and Internal Medicine and Danish Diabetes Academy, Aarhus University Hospital, Aarhus, Denmark Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark.
    Nørregaard, Rikke
    Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark.
    Flyvbjerg, Allan
    Department of Endocrinology and Internal Medicine and Danish Diabetes Academy, Aarhus University Hospital, Aarhus, Denmark Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark.
    Pedersen, Michael
    Department of Clinical Medicine, MR Research Centre, Aarhus University, Aarhus, Denmark Comparative Medicine Lab, Aarhus University, Aarhus, Denmark.
    Palm, Fredrik
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
    Ardenkjær-Larsen, Jan Henrik
    Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark Department of Electrical Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark GE Healthcare, Broendby, Denmark.
    Insufficient insulin administration to diabetic rats increases substrate utilization and maintains lactate production in the kidney.2014In: Physiological Reports, E-ISSN 2051-817X, ISSN 2051-817X, Vol. 2, no 12Article in journal (Refereed)
    Abstract [en]

    Good glycemic control is crucial to prevent the onset and progression of late diabetic complications, but insulin treatment often fails to achieve normalization of glycemic control to the level seen in healthy controls. In fact, recent experimental studies indicate that insufficient treatment with insulin, resulting in poor glycemic control, has an additional effect on progression of late diabetic complications, than poor glycemic control on its own. We therefore compared renal metabolic alterations during conditions of poor glycemic control with and without suboptimal insulin administration, which did not restore glycemic control, to streptozotocin (STZ)-diabetic rats using noninvasive hyperpolarized (13)C-pyruvate magnetic resonance imaging (MRI) and blood oxygenation level-dependent (BOLD) (1)H-MRI to determine renal metabolic flux and oxygen availability, respectively. Suboptimal insulin administration increased pyruvate utilization and metabolic flux via both anaerobic and aerobic pathways in diabetic rats even though insulin did not affect kidney oxygen availability, HbA1c, or oxidative stress. These results imply direct effects of insulin in the regulation of cellular substrate utilization and metabolic fluxes during conditions of poor glycemic control. The study demonstrates that poor glycemic control in combination with suboptimal insulin administration accelerates metabolic alterations by increasing both anaerobic and aerobic metabolism resulting in increased utilization of energy substrates. The results demonstrate the importance of tight glycemic control in insulinopenic diabetes, and that insulin, when administered insufficiently, adds an additional burden on top of poor glycemic control.

  • 27. Laustsen, Christoffer
    et al.
    Lipsø, Kasper
    Ostergaard, Jakob Appel
    Nørregaard, Rikke
    Flyvbjerg, Allan
    Pedersen, Michael
    Palm, Fredrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Ardenkjær-Larsen, Jan Henrik
    Insufficient insulin administration to diabetic rats increases substrate utilization and maintains lactate production in the kidney2014In: Physiological Reports, E-ISSN 2051-817X, Vol. 2, no 12, article id e12233Article in journal (Refereed)
    Abstract [en]

    Good glycemic control is crucial to prevent the onset and progression of late diabetic complications, but insulin treatment often fails to achieve normalization of glycemic control to the level seen in healthy controls. In fact, recent experimental studies indicate that insufficient treatment with insulin, resulting in poor glycemic control, has an additional effect on progression of late diabetic complications, than poor glycemic control on its own. We therefore compared renal metabolic alterations during conditions of poor glycemic control with and without suboptimal insulin administration, which did not restore glycemic control, to streptozotocin (STZ)-diabetic rats using noninvasive hyperpolarized (13)C-pyruvate magnetic resonance imaging (MRI) and blood oxygenation level-dependent (BOLD) (1)H-MRI to determine renal metabolic flux and oxygen availability, respectively. Suboptimal insulin administration increased pyruvate utilization and metabolic flux via both anaerobic and aerobic pathways in diabetic rats even though insulin did not affect kidney oxygen availability, HbA1c, or oxidative stress. These results imply direct effects of insulin in the regulation of cellular substrate utilization and metabolic fluxes during conditions of poor glycemic control. The study demonstrates that poor glycemic control in combination with suboptimal insulin administration accelerates metabolic alterations by increasing both anaerobic and aerobic metabolism resulting in increased utilization of energy substrates. The results demonstrate the importance of tight glycemic control in insulinopenic diabetes, and that insulin, when administered insufficiently, adds an additional burden on top of poor glycemic control.

  • 28.
    Li, Hao
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences. Swedish Univ Agr Sci, Dept Anim Nutr & Management, POB 7024, S-75007 Uppsala, Sweden..
    Roos, Stefan
    Swedish Univ Agr Sci, Uppsala BioCtr, Dept Microbiol, Uppsala, Sweden..
    Jonsson, Hans
    Swedish Univ Agr Sci, Uppsala BioCtr, Dept Microbiol, Uppsala, Sweden..
    Ahl, David
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Dicksved, Johan
    Swedish Univ Agr Sci, Dept Anim Nutr & Management, POB 7024, S-75007 Uppsala, Sweden..
    Lindberg, Jan Erik
    Swedish Univ Agr Sci, Dept Anim Nutr & Management, POB 7024, S-75007 Uppsala, Sweden..
    Lundh, Torbjorn
    Swedish Univ Agr Sci, Dept Anim Nutr & Management, POB 7024, S-75007 Uppsala, Sweden..
    Effects of Lactobacillus johnsonii and Lactobacillus reuteri on gut barrier function and heat shock proteins in intestinal porcine epithelial cells2015In: Physiological Reports, E-ISSN 2051-817X, Vol. 3, no 4, article id e12355Article in journal (Refereed)
    Abstract [en]

    Heat shock proteins (HSPs) are a set of highly conserved proteins that can serve as intestinal gate keepers in gut homeostasis. Here, effects of a probiotic, Lactobacillus rhamnosus GG (LGG), and two novel porcine isolates, Lactobacillus johnsonii strain P47-HY and Lactobacillus reuteri strain P43-HUV, on cyto-protective HSP expression and gut barrier function, were investigated in a porcine IPEC-J2 intestinal epithelial cell line model. The IPEC-J2 cells polarized on a permeable filter exhibited villus-like cell phenotype with development of apical microvilli. Western blot analysis detected HSP expression in IPEC-J2 and revealed that L. johnsonii and L. reuteri strains were able to significantly induce HSP27, despite high basal expression in IPEC-J2, whereas LGG did not. For HSP72, only the supernatant of L. reuteri induced the expression, which was comparable to the heat shock treatment, which indicated that HSP72 expression was more stimulus specific. The protective effect of lactobacilli was further studied in IPEC-J2 under an enterotoxigenic Escherichia coli (ETEC) challenge. ETEC caused intestinal barrier destruction, as reflected by loss of cell-cell contact, reduced IPEC-J2 cell viability and transepithelial electrical resistance, and disruption of tight junction protein zonula occludens-1. In contrast, the L. reuteri treatment substantially counteracted these detrimental effects and preserved the barrier function. L. johnsonii and LGG also achieved barrier protection, partly by directly inhibiting ETEC attachment. Together, the results indicate that specific strains of Lactobacillus can enhance gut barrier function through cytoprotective HSP induction and fortify the cell protection against ETEC challenge through tight junction protein modulation and direct interaction with pathogens.

  • 29.
    Mandic, Mirko
    et al.
    Karolinska Univ Hosp, Sweden; Karolinska Univ Hosp, Sweden.
    Forsgren, Mikael
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics. AMRA Med AB, Linkoping, Sweden.
    Romu, Thobias
    AMRA Med AB, Linkoping, Sweden.
    Widholm, Per
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping. AMRA Med AB, Linkoping, Sweden.
    Sundblad, Patrik
    Karolinska Univ Hosp, Sweden; Karolinska Univ Hosp, Sweden.
    Gustafsson, Thomas
    Karolinska Univ Hosp, Sweden; Karolinska Univ Hosp, Sweden.
    Rullman, Eric
    Karolinska Univ Hosp, Sweden; Karolinska Univ Hosp, Sweden.
    Interval-induced metabolic perturbation determines tissue fluid shifts into skeletal muscle2021In: Physiological Reports, E-ISSN 2051-817X, Vol. 9, no 7, article id e14841Article in journal (Refereed)
    Abstract [en]

    Intense interval exercise has proven to be as effective as traditional endurance exercise in improving maximal oxygen uptake. Shared by these two exercise regimes is an acute reduction in plasma volume, which is a suggested stimulus behind exercise-induced increases in blood volume and maximal oxygen uptake. This study aimed to link exercise-induced metabolic perturbation with volume shifts into skeletal muscle tissue. Ten healthy subjects (mean age 33 +/- 8 years, 5 males and 5 females) performed three 30 s all-out sprints on a cycle ergometer. Upon cessation of exercise magnetic resonance imaging, (31)Phosphorus magnetic resonance spectroscopy and blood samples were used to measure changes in muscle volume, intramuscular energy metabolites and plasma volume. Compared to pre-exercise, muscle volume increased from 1147.1 +/- 35.6 ml to 1283.3 +/- 11.0 ml 8 min post-exercise. At 30 min post-exercise, muscle volume was still higher than pre-exercise (1147.1 +/- 35.6 vs. 1222.2 +/- 6.8 ml). Plasma volume decreased by 16 +/- 3% immediately post-exercise and recovered back to - 5 +/- 6% after 30 min. Principal component analysis of exercise performance, muscle and plasma volume changes as well as changes in intramuscular energy metabolites showed generally strong correlations between metabolic and physiological variables. The strongest predictor for the volume shifts of muscle and plasma was the magnitude of glucose-6-phosphate accumulation post-exercise. Interval training leads to large metabolic and hemodynamic perturbations with accumulation of glucose-6-phosphate as a possible key event in the fluid flux between the vascular compartment and muscle tissue.

    Download full text (pdf)
    fulltext
  • 30.
    Manselin, Tom A
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Södergård, Olof
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Larsen, Filip J
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Research group for Mitokondriell funktion och metabolisk kontroll.
    Lindholm, Peter
    Karolinska institutet.
    Aerobic efficiency is associated with the improvement in maximal power output during acute hyperoxia.2017In: Physiological Reports, E-ISSN 2051-817X, Vol. 5, no 2, article id e13119Article in journal (Refereed)
    Abstract [en]

    This study investigated the relationship between aerobic efficiency during cycling exercise and the increase in physical performance with acute hyperoxic exposure (FiO2 ~31%) (HOX) and also tested the hypothesis that fat oxidation could be increased by acute hyperoxia. Fourteen males and four females were recruited for two sessions, where they exercised for 2 × 10 min at 100 W to determine efficiency. HOX and normoxia (NOX) were administered randomly on both occasions to account for differences in nitrogen exchange. Thereafter, a progressive ramp test was performed to determine VO2max and maximal power output (Wmax). After 30 min rest, workload was set to 80% of maximal power output (Wmax) for a time to exhaustion test (TTE). At 100W gross efficiency was reduced from 19.4% during NOX to 18.9% during HOX (P ≤ 0.0001). HOX increased fat oxidation at 100 W by 52% from 3.41 kcal min(-1) to 5.17 kcal min(-1) (P ≤ 0.0001) with a corresponding reduction in carbohydrate oxidation. Wmax increased by 2.4% from 388.8 (±82.1) during NOX to 397.8 (±83.5) during HOX (P ≤ 0.0001). SaO2 was higher in HOX both at the end of the maximal exercise test and TTE. Subjects with a high level of efficiency in NOX had a larger improvement in Wmax with HOX, in agreement with the hypothesis that an optimum level of efficiency exists that maximizes power production. No association between mitochondrial excess capacity and endurance performance was found; increases in oxygen supply seemed to increase maximal aerobic power production and maintain/increase endurance capacity at the same relative workload.

    Download full text (pdf)
    fulltext
  • 31. McDonnell, Adam C
    et al.
    Eiken, Ola
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Environmental Physiology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Swedish Aerospace Physiology Centre, SAPC.
    Mekjavic, Igor B
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Swedish Aerospace Physiology Centre, SAPC. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Environmental Physiology. Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada.
    Žlak, Nik
    Drobnič, Matej
    The influence of a sustained 10-day hypoxic bed rest on cartilage biomarkers and subchondral bone in females: The FemHab study.2020In: Physiological Reports, E-ISSN 2051-817X, Vol. 8, no 8, article id e14413Article in journal (Refereed)
    Abstract [en]

    This study assessed the influence of a 10-day hypoxic bed rest on cartilage biomarkers and subchondral bone density across the patellofemoral joint (PFJ). Within clinical settings hypoxic tissue may arise in several types of disorders. Furthermore, a hypoxic environment is being considered for space flight habitats in the near future. Female participants (N = 12) participated in this study comprising three 10-day interventions: hypoxic ambulation (HAMB), normoxic bed rest (NBR), and hypoxic bed rest (HBR). Venous samples were collected prior to (day -2: Pre) and during the intervention (days 2 and 5), immediately before reambulation (D11) and 24 hr post intervention (R1). Blood samples were analyzed for: aggrecan, hyaluronan, Type IIA procollagen amino terminal propeptide (PIIANP), and cartilage oligomeric matrix protein (COMP). Total bone mineral density (BMD) in eight regions (2 mm × 10 mm) across the PFJ was determined. The three interventions (HAMB, HBR, and NBR) did not induce any significant changes in the cartilage biomarkers of hyaluronan or PIIANP. Aggrecan increased during the HAMB trial to 2.02 fold the Pre value. COMP decreased significantly in both NBR & HBR compared to HAMB on D5. There were significant differences in BMD measured across the PFJ from cortical patellar bone (735 to 800 mg/cm3 ) to femur trabecular (195 to 226 mg/cm3 ). However, there were no significant changes in BMD from Pre to Post bed rest. These results indicate that there were no significant detectable effects of inactivity/unloading on subchondral bone density. The biomarker of cartilage, COMP, decreased on D5, whereas the addition of hypoxia to bed rest had no effect, it appears that hypoxia in combination with ambulation counteracted this decrease.

  • 32.
    Mikolka, Pavol
    et al.
    Karolinska Inst, Div Neurogeriatr, Dept Neurobiol Care Sci & Soc, Huddinge, Sweden.;Comenius Univ, Jessenius Fac Med Martin, Biomed Ctr Martin, Martin, TN, Slovakia.;Comenius Univ, Jessenius Fac Med Martin, Dept Physiol, Martin, TN, Slovakia..
    Curstedt, Tore
    Karolinska Inst, Karolinska Univ Hosp, Dept Mol Med & Surg, Stockholm, Sweden..
    Feinstein, Riccardo
    Swedish Natl Vet Inst, Dept Pathol, Uppsala, Sweden..
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Grendar, Marian
    Comenius Univ, Jessenius Fac Med Martin, Biomed Ctr Martin, Martin, TN, Slovakia..
    Rising, Anna
    Karolinska Inst, Div Neurogeriatr, Dept Neurobiol Care Sci & Soc, Huddinge, Sweden.;Swedish Univ Agr Sci, Dept Anat Physiol & Biochem, Uppsala, Sweden..
    Johansson, Jan
    Karolinska Inst, Div Neurogeriatr, Dept Neurobiol Care Sci & Soc, Huddinge, Sweden..
    Impact of synthetic surfactant CHF5633 with SP-B and SP-C analogues on lung function and inflammation in rabbit model of acute respiratory distress syndrome2021In: Physiological Reports, E-ISSN 2051-817X, Vol. 9, no 1, article id e14700Article in journal (Refereed)
    Abstract [en]

    Acute respiratory distress syndrome (ARDS) is associated with diffuse inflammation, alveolar epithelial damage, and leakage of plasma proteins into the alveolar space, which together contribute to inactivation of pulmonary surfactant and respiratory failure. Exogenous surfactant delivery is therefore considered to hold potential for ARDS treatment, but clinical trials with natural derived surfactant or synthetic surfactant containing a surfactant protein C (SP-C) analogue have been negative. Synthetic surfactant CHF5633, containing analogues of SP-B and SP-C, may be effective against ARDS. The aim here was to compare treatment effects of CHF5633 and animal-derived surfactant poractant alfa in animal model of ARDS. ARDS was induced in adult New Zealand rabbits by mild lung lavages followed by injurious ventilation until respiratory failure (P/F ratio <26.7 kPa). The animals were then treated with intratracheal bolus of 200 mg/kg CHF5633 or poractant alfa (Curosurf(R)), or air as control. The animals were subsequently ventilated for an additional 4 hr and respiratory parameters were recorded regularly. Postmortem, histological analysis, degree of lung edema, and levels of the cytokines TNF alpha, IL-6, and IL-8 in lung homogenates were evaluated. Both surfactant preparations improved lung function, reduced the levels of pro-inflammatory cytokines, and degree of lung edema to very similar degrees versus the controls. No significant differences in any of the analyzed parameters were observed between the CHF5633- and poractant alfa-treated groups. This study indicates that single dose of CHF5633 improves lung function and attenuates inflammation as effectively as poractant alfa in experimental ARDS caused by injurious ventilation.

    Download full text (pdf)
    fulltext
  • 33.
    Moberg, Marcus
    et al.
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's research group.
    Hendo, Gina
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences.
    Jakobsson, Madelene
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences.
    Mattsson, C Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Ekblom-Bak, Elin
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Flockhart, Mikael
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Research group for Mitokondriell funktion och metabolisk kontroll.
    Pontén, Marjan
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Söderlund, Karin
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Ekblom, Björn
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology, Björn Ekblom's research group.
    Increased autophagy signaling but not proteasome activity in human skeletal muscle after prolonged low-intensity exercise with negative energy balance2017In: Physiological Reports, E-ISSN 2051-817X, Vol. 5, no 23, article id e13518Article in journal (Refereed)
    Abstract [en]

    Little is known about the molecular regulation of skeletal muscle protein turnover during exercise in field conditions where energy is intake inadequate. Here, 17 male and 7 female soldiers performed an 8 day long field based military operation. Vastus lateralis muscle biopsies, in which autophagy, the ubiquitin-proteasome system and the mTORC1 signaling pathway where studied, were collected before and after the operation. The 187 h long operation resulted in a 15% and 29% negative energy balance as well as a 4.1% and 4.6% loss of body mass in women and men respectively. After the operation protein levels of ULK1 as well as the phosphorylation of ULK1Ser317 and ULK1Ser555 had increased by 11%, 39% and 13%, respectively, and this was supported by a 17% increased phosphorylation of AMPKThr172 (P<0.05). The LC3b-I/II ratio was 3-fold higher after compared to before the operation (P<0.05), whereas protein levels of p62/SQSTM1 were unchanged. The β1, β2, and β5 activity of the proteasome and protein levels of MAFbx did not change, while levels of MuRF-1 were slightly reduced (6%, P<0.05). Protein levels and phosphorylation status of key components in the mTORC1 signaling pathway remained at basal levels after the operation. Muscle levels of glycogen decreased from 269±12 to 181±9 mmol ∙ kg dry muscle-1 after the exercise period (P<0.05). In conclusion, the 8 days of field based exercise resulted in induction of autophagy without any increase in proteasome activity or protein ubiquitination. Simultaneously, the regulation of protein synthesis through the mTORC1 signaling pathway was maintained.

    Download full text (pdf)
    fulltext
    Download (pdf)
    sammanfattning
  • 34. Rullman, E
    et al.
    Mekjavic, IB
    Fischer, H
    Eiken, Ola
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Environmental Physiology.
    PlanHab (Planetary Habitat Simulation): the combined and separate effects of 21 days bed rest and hypoxic confinement on human skeletal muscle miRNA expression.2016In: Physiological Reports, E-ISSN 2051-817X, Vol. 4, no 8Article in journal (Refereed)
  • 35.
    Salunkhe, Vishal A.
    et al.
    Lund Univ, Lund Univ Diabet Ctr, Dept Clin Sci Malmo, Islet Cell Exocytosis, CRC 91-11,SUS Malmo,Box 50332, S-20213 Malmo, Sweden..
    Ofori, Jones K.
    Lund Univ, Lund Univ Diabet Ctr, Dept Clin Sci Malmo, Islet Cell Exocytosis, CRC 91-11,SUS Malmo,Box 50332, S-20213 Malmo, Sweden..
    Gandasi, Nikhil R
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Salo, Sofia A.
    Lund Univ, Lund Univ Diabet Ctr, Dept Clin Sci Malmo, Islet Cell Exocytosis, CRC 91-11,SUS Malmo,Box 50332, S-20213 Malmo, Sweden..
    Hansson, Sofia
    Lund Univ, Lund Univ Diabet Ctr, Dept Clin Sci Malmo, Islet Cell Exocytosis, CRC 91-11,SUS Malmo,Box 50332, S-20213 Malmo, Sweden..
    Andersson, Markus E.
    Lund Univ, Lund Univ Diabet Ctr, Dept Clin Sci Malmo, Islet Cell Exocytosis, CRC 91-11,SUS Malmo,Box 50332, S-20213 Malmo, Sweden..
    Wendt, Anna
    Lund Univ, Lund Univ Diabet Ctr, Dept Clin Sci Malmo, Islet Cell Exocytosis, CRC 91-11,SUS Malmo,Box 50332, S-20213 Malmo, Sweden..
    Barg, Sebastian
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Esguerra, Jonathan L. S.
    Lund Univ, Lund Univ Diabet Ctr, Dept Clin Sci Malmo, Islet Cell Exocytosis, CRC 91-11,SUS Malmo,Box 50332, S-20213 Malmo, Sweden..
    Eliasson, Lena
    Lund Univ, Lund Univ Diabet Ctr, Dept Clin Sci Malmo, Islet Cell Exocytosis, CRC 91-11,SUS Malmo,Box 50332, S-20213 Malmo, Sweden..
    MiR-335 overexpression impairs insulin secretion through defective priming of insulin vesicles2017In: Physiological Reports, E-ISSN 2051-817X, Vol. 5, no 21, article id e13493Article in journal (Refereed)
    Abstract [en]

    MicroRNAs contribute to the maintenance of optimal cellular functions by fine-tuning protein expression levels. In the pancreatic beta-cells, imbalances in the exocytotic machinery components lead to impaired insulin secretion and type 2 diabetes (T2D). We hypothesize that dysregulated miRNA expression exacerbates beta-cell dysfunction, and have earlier shown that islets from the diabetic GK-rat model have increased expression of miRNAs, including miR-335-5p (miR-335). Here, we aim to determine the specific role of miR-335 during development of T2D, and the influence of this miRNA on glucose-stimulated insulin secretion and Ca2+-dependent exocytosis. We found that the expression of miR-335 negatively correlated with secretion index in human islets of individuals with prediabetes. Overexpression of miR-335 in human EndoC-beta H1 and in rat INS-1 832/13 cells (OE335) resulted in decreased glucose-stimulated insulin secretion, and OE335 cells showed concomitant reduction in three exocytotic proteins: SNAP25, Syntaxin-binding protein 1 (STXBP1), and synaptotagmin 11 (SYT11). Single-cell capacitance measurements, complemented with TIRF microscopy of the granule marker NPY-mEGFP demonstrated a significant reduction in exocytosis in OE335 cells. The reduction was not associated with defective docking or decreased Ca2+ current. More likely, it is a direct consequence of impaired priming of already docked granules. Earlier reports have proposed reduced granular priming as the cause of reduced first-phase insulin secretion during prediabetes. Here, we show a specific role of miR-335 in regulating insulin secretion during this transition period. Moreover, we can conclude that miR-335 has the capacity to modulate insulin secretion and Ca2+-dependent exocytosis through effects on granular priming.

    Download full text (pdf)
    fulltext
  • 36.
    Schmitt, Joachim
    et al.
    RehaZentren Baden Wurttemberg gGmbH, Rehaklin Kurpk, Bad Kissingen, Germany.
    Lindner, Nathalie
    Julius Maximilians Univ Wurzburg, Dept Sport Sci, Integrat & Expt Training Sci, Wurzburg, Germany.
    Reuss-Borst, Monika
    RehaZentren Baden Wurttemberg gGmbH, Rehaklin Kurpk, Bad Kissingen, Germany.
    Holmberg, Hans-Christer
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences. Univ British Columbia, Sch Kinesiol, Vancouver, BC, Canada.
    Sperlich, Billy
    Julius Maximilians Univ Wurzburg, Dept Sport Sci, Integrat & Expt Training Sci, Wurzburg, Germany.
    A 3-week multimodal intervention involving high-intensity interval training in female cancer survivors: a randomized controlled trial2016In: Physiological Reports, E-ISSN 2051-817X, Vol. 4, no 3, article id e12693Article in journal (Refereed)
    Abstract [en]

    To compare the effects of a 3-week multimodal rehabilitation involving supervised high-intensity interval training (HIIT) on female breast cancer survivors with respect to key variables of aerobic fitness, body composition, energy expenditure, cancer-related fatigue, and quality of life to those of a standard multimodal rehabilitation program. A randomized controlled trial design was administered. Twenty-eight women, who had been treated for cancer were randomly assigned to either a group performing exercise of low-to-moderate intensity (LMIE; n = 14) or a group performing high-intensity interval training (HIIT; n = 14) as part of a 3-week multimodal rehabilitation program. No adverse events related to the exercise were reported. Work economy improved following both HIIT and LMIE, with improved peak oxygen uptake following LMIE. HIIT reduced mean total body fat mass with no change in body mass, muscle or fat-free mass (best P < 0.06). LMIE increased muscle and total fat-free body mass. Total energy expenditure (P = 0.45) did not change between the groups, whereas both improved quality of life to a similar high extent and lessened cancer-related fatigue. This randomized controlled study demonstrates that HIIT can be performed by female cancer survivors without adverse health effects. Here, HIIT and LMIE both improved work economy, quality of life and cancer-related fatigue, body composition or energy expenditure. Since the outcomes were similar, but HIIT takes less time, this may be a time-efficient strategy for improving certain aspects of the health of female cancer survivors.

    Download full text (pdf)
    fulltext
  • 37.
    Schmitt, Joachim
    et al.
    RehaZentren Baden Wurttemberg gGmbH, Rehaklin Kurpk, Bad Kissingen, Germany.
    Lindner, Nathalie
    Julius Maximilians Univ Wurzburg, Dept Sport Sci, Integrat & Expt Training Sci, Wurzburg, Germany.
    Reuss-Borst, Monika
    RehaZentren Baden Wurttemberg gGmbH, Rehaklin Kurpk, Bad Kissingen, Germany.
    Holmberg, Hans-Christer
    Mittuniversitetet, Avdelningen för hälsovetenskap.
    Sperlich, Billy
    Julius Maximilians Univ Wurzburg, Dept Sport Sci, Integrat & Expt Training Sci, Wurzburg, Germany.
    A 3-week multimodal intervention involving high-intensity interval training in female cancer survivors: a randomized controlled trial2016In: Physiological Reports, E-ISSN 2051-817X, Vol. 4, no 3, article id e12693Article in journal (Refereed)
    Abstract [en]

    To compare the effects of a 3-week multimodal rehabilitation involving supervised high-intensity interval training (HIIT) on female breast cancer survivors with respect to key variables of aerobic fitness, body composition, energy expenditure, cancer-related fatigue, and quality of life to those of a standard multimodal rehabilitation program. A randomized controlled trial design was administered. Twenty-eight women, who had been treated for cancer were randomly assigned to either a group performing exercise of low-to-moderate intensity (LMIE; n = 14) or a group performing high-intensity interval training (HIIT; n = 14) as part of a 3-week multimodal rehabilitation program. No adverse events related to the exercise were reported. Work economy improved following both HIIT and LMIE, with improved peak oxygen uptake following LMIE. HIIT reduced mean total body fat mass with no change in body mass, muscle or fat-free mass (best P < 0.06). LMIE increased muscle and total fat-free body mass. Total energy expenditure (P = 0.45) did not change between the groups, whereas both improved quality of life to a similar high extent and lessened cancer-related fatigue. This randomized controlled study demonstrates that HIIT can be performed by female cancer survivors without adverse health effects. Here, HIIT and LMIE both improved work economy, quality of life and cancer-related fatigue, body composition or energy expenditure. Since the outcomes were similar, but HIIT takes less time, this may be a time-efficient strategy for improving certain aspects of the health of female cancer survivors.

  • 38.
    Svensson Holm, Ann-Charlotte B
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Lindgren, Isa
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Österman, Hanna
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Altimiras, Jordi
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Thyroid hormone does not induce maturation of embryonicchicken cardiomyocytes in vitro2014In: Physiological Reports, E-ISSN 2051-817X, Vol. 2, no 12, p. e12182-Article in journal (Refereed)
    Abstract [sv]

    Fetal cardiac growth in mammalian models occurs primarily by cell proliferation(hyperplasia). However, most cardiomyocytes lose the ability to proliferateclose to term and heart growth continues by increasing cell size(hypertrophy). In mammals, the thyroid hormone triiodothyronine (T3) is animportant driver of this process. Chicken cardiomyocytes, however, keep theirproliferating ability long after hatching but little information is available onthe mechanisms controlling cell growth and myocyte maturation in thechicken heart. Our aim was to study the role of T3 on proliferation and differentiationof embryonic chicken cardiomyocytes (ECCM), enzymaticallyisolated from 19-day-old embryos and to compare the effects to those of insulin-like growth factor-1 (IGF-1) and phenylephrine (PE). Hyperplasia wasmeasured using a proliferation assay (MTS) and hypertrophy/multinucleationwas analyzed morphologically by phalloidin staining of F-actin and nuclearstaining with DAPI. We show that IGF-1 induces a significant increase inECCM proliferation (30%) which is absent with T3 and PE. PE induced bothhypertrophy (61%) and multinucleation (41%) but IGF-1 or T3 did not. Inconclusion, we show that T3 does not induce maturation or proliferation ofcardiomyocytes, while IGF-1 induces cardiomyocyte proliferation and PEinduces maturation of cardiomyocytes.

  • 39. Talbot, Nick P
    et al.
    Cheng, Hung-Yuan
    Hanstock, Helen
    Mid Sweden University, Faculty of Human Sciences, Department of Health Sciences (HOV).
    Smith, Thomas G
    Dorrington, Keith L
    Robbins, Peter A
    Hypoxic pulmonary vasoconstriction does not limit maximal exercise capacity in healthy volunteers breathing 12% oxygen at sea level.2024In: Physiological Reports, E-ISSN 2051-817X, Vol. 12, no 4, article id e15944Article in journal (Refereed)
    Abstract [en]

    Maximal exercise capacity is reduced at altitude or during hypoxia at sea level. It has been suggested that this might reflect increased right ventricular afterload due to hypoxic pulmonary vasoconstriction. We have shown previously that the pulmonary vascular sensitivity to hypoxia is enhanced by sustained isocapnic hypoxia, and inhibited by intravenous iron. In this study, we tested the hypothesis that elevated pulmonary artery pressure contributes to exercise limitation during acute hypoxia. Twelve healthy volunteers performed incremental exercise tests to exhaustion breathing 12% oxygen, before and after sustained (8-h) isocapnic hypoxia at sea level. Intravenous iron sucrose (n = 6) or saline placebo (n = 6) was administered immediately before the sustained hypoxia. In the placebo group, there was a substantial (12.6 ± 1.5 mmHg) rise in systolic pulmonary artery pressure (SPAP) during sustained hypoxia, but no associated fall in maximal exercise capacity breathing 12% oxygen. In the iron group, the rise in SPAP during sustained hypoxia was markedly reduced (3.4 ± 1.0 mmHg). There was a small rise in maximal exercise capacity following sustained hypoxia within the iron group, but no overall effect of iron, compared with saline. These results do not support the hypothesis that elevated SPAP inhibits maximal exercise capacity during acute hypoxia in healthy volunteers.

    Download full text (pdf)
    fulltext
  • 40.
    Tamás, Éva
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Decision support for assessment of left ventricular diastolic function2018In: Physiological Reports, E-ISSN 2051-817X, Vol. 6, no 16Article in journal (Refereed)
    Abstract [en]

    Echocardiographic assessment of the left ventricular diastolic function (LVDF), an integrated part of evaluation of left ventricular function is still a delicate task and is performed with substantial inter-rater variability. Therefore, we aimed to create and evaluate a guidelines-based automated decision support. An algorithm was created for a hierarchical analysis of LVDF based on variables as recommended by the latest guidelines. Age-adjusted normal ranges were pooled from previously published studies into an integrated reference table. For proof-of-concept, 20 echocardiographic examinations were analyzed offline by four experienced physicians with more than 10 years of echocardiographic experience. The first assessments were to be performed as they would be in the clinical practice. Six months later, the assessments were repeated based on the 2017 ASE/EACVI guidelines. The overall inter-rater agreement for the first clinical assessments was moderate, while the guidelines-based assessments had only fair inter-rater agreement. Both kinds of manual assessment had poor agreement with the standardized automated assessment algorithm of LVDF. In conclusion, the presented automated decision support for evaluation of diastolic LV function by Doppler echocardiography is mainly based on current guidelines involving multiple parameters in combination. Incorporating age dependency aspects in our program (available for use at https://liu.se/en/research/left-ventricular-diastolic-function-decision-support) enhances the accuracy of the evaluation and reduces variability in evaluation of LVDF. The large inter-rater variation in classification in this study also underscores the usefulness of tools to support a standardized evaluation.

    Download full text (pdf)
    fulltext
  • 41.
    Turner, Anita J.
    et al.
    Macquarie Univ, Australian Sch Adv Med, Sydney, NSW 2109, Australia.;Univ New South Wales, Sch Med Sci, Dept Physiol, Sydney, NSW, Australia..
    Brown, Russell D.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology. Univ New South Wales, Sch Med Sci, Dept Physiol, Sydney, NSW, Australia..
    Boyce, Amanda
    Univ New South Wales, Sch Med Sci, Dept Physiol, Sydney, NSW, Australia..
    Gibson, Karen J.
    Univ New South Wales, Sch Med Sci, Dept Physiol, Sydney, NSW, Australia..
    Persson, A. Erik G.
    Univ New South Wales, Sch Med Sci, Dept Physiol, Sydney, NSW, Australia.;Uppsala Univ, Dept Med Cell Biol, Div Integrat Physiol, Uppsala, Sweden..
    Fetal tubuloglomerular feedback in an ovine model of mild maternal renal disease2015In: Physiological Reports, E-ISSN 2051-817X, Vol. 3, no 7, article id e12448Article in journal (Refereed)
    Abstract [en]

    Fetuses of pregnant ewes, which were subtotally nephrectomized prior to mating, were studied to assess whether mild maternal renal impairment would affect fetal tubuloglomerular feedback (TGF) under control conditions and after the inhibition of macula densa-derived nitric oxide (NO). Based on previous observations we hypothesized that, the TGF curve of fetuses of subtotally nephrectomized (STNx) ewes would resemble that of a volume expanded fetus with a high production rate of NO and that inhibition of neuronal nitric oxide synthase (nNOS) would increase the sensitivity of the TGF system in these fetuses. Renal function studies were performed on anaesthetized fetal sheep (133-140 days gestation; term similar to 150 days; Isoflurane 2-4% in oxygen). Fetuses were removed from the uterus and placed in a water bath (39.5 degrees C) while maintaining umbilical blood flow. Glomerular filtration rate (GFR) and urine flow rate were markedly increased in fetuses of STNx ewes compared to fetuses of untreated ewes. Interestingly, and contrary to our hypothesis, the fetuses of STNx ewes exhibited no difference in TGF sensitivity in the presence or absence of 7-nitroindazole (7NI; nNOS inhibitor), compared to fetuses of untreated ewes, although sensitivity and reactivity increased in both groups after 7NI. There was however, a decrease in the stop flow pressure and net filtration pressure with an increase in the filtration coefficient (K-f). These factors suggest that maternal renal impairment drives the glomerular hypertrophy which has previously been found to be present in the neonatal period. Thus, we conclude that at similar to 138 days gestation, the fetal kidney has matured functionally and fetuses of STNx ewes are able to maintain fluid and electrolyte homeostasis even in the presence of increased transplacental flux.

    Download full text (pdf)
    fulltext
  • 42.
    Ullsten, Sara
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Espes, Daniel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Transplantation and regenerative medicine.
    Quach, My
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Fex, Malin
    Department of Clinical Sciences, Lund University Diabetes Center, Lund University, Lund, Sweden.
    Sandberg, Monica
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Carlsson, Per-Ola
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Transplantation and regenerative medicine.
    Highly blood perfused, highly metabolically active pancreatic islets may be more susceptible for immune attack2020In: Physiological Reports, E-ISSN 2051-817X, Vol. 8, no 13, article id e14444Article in journal (Refereed)
    Abstract [en]

    Differences in pancreatic islet susceptibility during type 1 diabetes development may be explained by interislet variations. This study aimed to investigate if heterogeneities in vascular support and metabolic activity in rat and human islets may explain why some islets are attacked earlier than other islets. In rats, highly blood perfused islets were identified by injection of microspheres into the ascending aorta, whereas a combination of anterograde and retrograde injections of microspheres into pancreas was used to determine the islet vascular drainage system. Highly blood perfused islets had superior function and lower glucose threshold for insulin release when compared with other islets. These islets had a preferential direct venous drainage to the portal vein, whereas other islets mainly were incorporated into the exocrine capillary system. In BioBreeding rats, the hypothesis that islets with high islet blood perfusion was more prone to immune cell infiltration was investigated. Indeed, highly blood perfused islets were the first affected by the immune attack. In human subjects, differences in glucose threshold for insulin (C-peptide) secretion was evaluated in individuals recently diagnosed for type 1 diabetes and compared to control subjects. A preferential loss of capacity for insulin release in response to low glucose concentrations was observed at debut of type 1 diabetes. Our study indicates that highly blood perfused islets with direct venous drainage and lower glucose threshold for insulin release are of great importance for normal glucose homeostasis. At the same time, these highly metabolically active islets were the primary target of the immune system.

    Download full text (pdf)
    fulltext
  • 43.
    von Gruenewaldt, Anna
    et al.
    Linköping University, Department of Health, Medicine and Caring Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Clinical Physiology in Linköping.
    Nylander, Eva
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Clinical Physiology in Linköping.
    Hedman, Kristofer
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Clinical Physiology in Linköping.
    Classification and occurrence of an abnormal breathing pattern during cardiopulmonary exercise testing in subjects with persistent symptoms following COVID-19 disease2022In: Physiological Reports, E-ISSN 2051-817X, Vol. 10, no 4, article id e15197Article in journal (Refereed)
    Abstract [en]

    Reduced exercise capacity and several limiting symptoms during exercise have been reported following severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. From clinical observations, we hypothesized that an abnormal breathing pattern (BrP) during exercise may be common in these patients and related to reduced exercise capacity. We aimed to (a) evaluate a method to classify the BrP as normal/abnormal or borderline in terms of inter-rater agreement; (b) determine the occurrence of an abnormal BrP in patients with post-COVID; and (c) compare characteristics of post-COVID patients with normal and abnormal BrP. In a retrospective, cross-sectional study of patients referred for CPET due to post-COVID April 2020-April 2021, we selected subjects without a history of intensive care and with available medical records. Three raters independently categorized patients BrP as normal, abnormal, or borderline, using four traditional CPET plots (respiratory exchange ratio, tidal volume over ventilation, ventilatory equivalent for oxygen, and ventilation over time). Out of 20 patients (11 male), 10 were categorized as having a normal, 7 an abnormal, and three a borderline BrP. Inter-rater agreement was good (Fleiss kappa: 0.66 [0.66-0.67]). Subjects with an abnormal BrP had lower peak ventilation, lower exercise capacity, similar ventilatory efficiency and a similar level of dyspnea at peak exercise, as did subjects with a normal BrP. Patients BrP was possible to classify with good agreement between observers. A third of patients had an abnormal BrP, associated with lower exercise capacity. which could possibly explain exercise related symptoms in some patients with post-COVID syndrome.

    Download full text (pdf)
    fulltext
1 - 43 of 43
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf