Project description:Acute physical exercise elicits changes in gene expression in skeletal muscles to promote metabolic changes and to repair exercise-induced muscle injuries. Here, we investigated the impact of a single bout of running exercise until exhaustion on global transcriptional profiles in porcine skeletal muscles. Using a combined microarray and candidate gene approach, we identified a suite of genes that are differentially expressed in muscles during post-exercise recovery. Thus, several members of the heat shock protein family and proteins associated with proteolytic events were significantly up-regulated, suggesting that protein breakdown, prevention of protein aggregation and stabilization of unfolded proteins are important processes for restoring cellular homeostasis. We also detected an up-regulation of genes, which have been reported to be associated with muscle cell proliferation and differentiation, possibly reflecting an activation, differentiation and fusion of satellite cells to facilitate repair of muscle damage. In addition, exercise increased expression of the nuclear hormone receptors, which regulates metabolic functions associated with lipid, carbohydrate and energy homeostasis. Finally, we observed an unanticipated involvement of long non-coding RNA transcripts, which have been implicated in RNA processing and nuclear retention of adenosine-to-inosine edited mRNAs. These findings expand the complexity of pathways affected by acute contractile activity of skeletal muscle, contributing to a better understanding of the molecular processes that occur in muscle tissue in the recovery phase. Gene expression study of the porcine muscle Biceps femoris in regard to exercise, pigs allowed to rest for 0 hours, 1 hour and 3 hours after exercise were compared with pigs that had not been exercising, using in-house printed porcine two-colour oligonucleotide microarrays.
Project description:Mechanisms underlying the sparing of masticatory muscle function relative to biceps femoris muscle in an experimental critical illness model
Project description:To investigate the influence of lifelong exercise training on the response of skeletal muscle to a bout of acute exercise we generated global transcriptomic data from long-term endurance (8 men, 8 women) and strength (8 men, 8 women) trained individuals and healthy age-matched untrained controls (8 men, 8 women). Skeletal muscle biopsies were taken from M. vastus lateralis before, directly after, and after 1h and 3hrs following acute exercise. All subjects completed one bout of acute endurance exercise and one bout of acute resistance exercise, separated by 4-8 weeks. All 384 samples were multiplexed in 4 lanes and sequenced (2x250bp paired end) on the Illumina NovaSeq 6000.
Project description:To investigate the influence of lifelong exercise training on the response of skeletal muscle to a bout of acute exercise we generated global transcriptomic data from long-term endurance (8 men, 8 women) and strength (8 men, 8 women) trained individuals and healthy age-matched untrained controls (8 men, 8 women). Skeletal muscle biopsies were taken from M. vastus lateralis before, directly after, and after 1h and 3hrs following acute exercise. All subjects completed one bout of acute endurance exercise and one bout of acute resistance exercise, separated by 4-8 weeks. All 384 samples were multiplexed in 4 lanes and sequenced (2x250bp paired end) on the Illumina NovaSeq 6000.
Project description:We examined global mRNA expression using cDNA microarrays in skeletal muscle of humans before, and 3h and 48h after a single bout of exhaustive endurance exercise (cycling). Keywords: Time course
Project description:Age-related declines in cardiorespiratory fitness and physical function are mitigated by regular endurance exercise in older adults. This may be due, in part, to changes in the transcriptional program of skeletal muscle following repeated bouts of exercise. However, the impact of chronic exercise training on the transcriptional response to an acute bout of endurance exercise has not been clearly determined. Here, we characterized baseline differences in muscle transcriptome and exercise-induced response in older adults who were active/endurance trained or sedentary. RNA-sequencing was performed on vastus lateralis biopsy specimens obtained before, immediately after, and 3 h following a bout of endurance exercise (40 min of cycling at 60%–70% of heart rate reserve). Using a recently developed bioinformatics approach, we found that transcript signatures related to type I myofibers, mitochondria, and endothelial cells were higher in active/endurance-trained adults and were associated with key phenotypic features including V̇o2peak, ATPmax, and muscle fiber proportion. Immune cell signatures were elevated in the sedentary group and linked to visceral and intermuscular adipose tissue mass. Following acute exercise, we observed distinct temporal transcriptional signatures that were largely similar among groups. Enrichment analysis revealed catabolic processes were uniquely enriched in the sedentary group at the 3-h postexercise timepoint. In summary, this study revealed key transcriptional signatures that distinguished active and sedentary adults, which were associated with difference in oxidative capacity and depot-specific adiposity. The acute response signatures were consistent with beneficial effects of endurance exercise to improve muscle health in older adults irrespective of exercise history and adiposity.