title: Regulation of skeletal muscle transcriptome in elderly men after 6 weeks of endurance training at lactate threshold intensity.
abstract: A compromised muscle function due to aging, sarcopenia and reduced level of physical activity can lead to metabolic complications and chronic diseases. Endurance exercise counters these diseases by inducing beneficial adaptations whose molecular mechanisms remain unclear. We have investigated the transcriptomic changes following mild-intensity endurance training in skeletal muscle of elderly men. Seven healthy subjects followed an exercise program of cycle ergometer training at lactate threshold (LT) level for 60 min/day, five times/week during six weeks. Physiological and transcriptomic changes were analyzed before and after training. LT training decreased percentage body fat and fasting levels of plasma glucose, while increasing high-density lipoprotein cholesterol and lecithin-cholesterol acyltransferase levels. Transcriptomic analysis revealed fast-to-slow fiber type transition, increased amount of mtDNA encoded transcripts and modulation of 12 transcripts notably related to extracellular matrix (ECM), oxidative phosphorylation (OXPHOS), as well as partially characterized and novel transcripts. The training simultaneously induced the expression of genes related to slow fiber type transition, OXPHOS and ECM, which might contribute to the improvement of glucose and lipid metabolisms and whole body aerobic capacity.
authors.affiliation: Molecular Endocrinology and Oncology Research Center, Laval University Medical Center, Québec, Canada.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Riedl
authors.forename: Mayumi
authors.initials: M
authors.lastname: Yoshioka
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Nishida
authors.forename: Takuro
authors.initials: T
authors.lastname: Tobina
authors.forename: René
authors.initials: R
authors.lastname: Paradis
authors.forename: Naoko
authors.initials: N
authors.lastname: Shono
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Jonny
authors.initials: J
authors.lastname: St-Amand
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology; D000368:Aged; D001786:Blood Glucose / Q000032:analysis; D008076:Cholesterol, HDL / Q000097:blood; D004272:DNA, Mitochondrial / Q000235:genetics; D004056:Differential Threshold; D005109:Extracellular Matrix / Q000378:metabolism; D005215:Fasting / Q000097:blood; D020869:Gene Expression Profiling; D006801:Humans; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism*; D010085:Oxidative Phosphorylation; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000097:blood; D010806:Physical Education and Training; D010807:Physical Endurance; D012313:RNA / Q000378:metabolism; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D008076:Cholesterol, HDL; D004272:DNA, Mitochondrial; D019344:Lactic Acid; D012313:RNA; D007862:Phosphatidylcholine-Sterol O-Acyltransferase