title: The effects of aging, physical training, and a single bout of exercise on mitochondrial protein expression in human skeletal muscle.
abstract: Aging results in a significant decline in aerobic capacity and impaired mitochondrial function. We have tested the effects of moderate physical activity on aerobic capacity and a single bout of exercise on the expression profile of mitochondrial biogenesis, and fusion and fission related genes in skeletal muscle of human subjects. Physical activity attenuated the aging-associated decline in VO2 max (p<0.05). Aging increased and a single exercise bout decreased the expression of nuclear respiratory factor-1 (NRF1), while the transcription factor A (TFAM) expression showed a strong relationship with VO(2max) and increased significantly in the young physically active group. Mitochondrial fission representing FIS1 was induced by regular physical activity, while a bout of exercise decreased fusion-associated gene expression. The expression of polynucleotide phosphorylase (PNPase) changed inversely in young and old groups and decreased with aging. The A2 subunit of cyclic AMP-activated protein kinase (AMPK) was induced by a single bout of exercise in skeletal muscle samples of both young and old subjects (p<0.05). Our data suggest that moderate levels of regular physical activity increases a larger number of mitochondrial biogenesis-related gene expressions in young individuals than in aged subjects. Mitochondrial fission is impaired by aging and could be one of the most sensitive markers of the age-associated decline in the adaptive response to physical activity.
authors.affiliation: Research Institute of Sport Science, Semmelweis University, Budapest, Hungary.
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Bori
authors.forename: Zhongfu
authors.initials: Z
authors.lastname: Zhao
authors.forename: Erika
authors.initials: E
authors.lastname: Koltai
authors.forename: Ioannis G
authors.initials: IG
authors.lastname: Fatouros
authors.forename: Athanasios Z
authors.initials: AZ
authors.lastname: Jamurtas
authors.forename: Ioannis I
authors.initials: II
authors.lastname: Douroudos
authors.forename: Gerasimos
authors.initials: G
authors.lastname: Terzis
authors.forename: Athanasios
authors.initials: A
authors.lastname: Chatzinikolaou
authors.forename: Apostolos
authors.initials: A
authors.lastname: Sovatzidis
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Draganidis
authors.forename: Istvan
authors.initials: I
authors.lastname: Boldogh
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Radak
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005786:Gene Expression Regulation / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008931:Mitochondria, Muscle / Q000378:metabolism / Q000502:physiology; D024101:Mitochondrial Proteins / Q000096:biosynthesis* / Q000235:genetics; D009124:Muscle Proteins / Q000096:biosynthesis / Q000235:genetics; D018482:Muscle, Skeletal / Q000378:metabolism / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D055815:Young Adult
chemical_list: D024101:Mitochondrial Proteins; D009124:Muscle Proteins; D012333:RNA, Messenger