title: Force-generation capacity of single vastus lateralis muscle fibers and physical function decline with age in African green vervet monkeys.
abstract: Previous studies on the contractile properties of human myofibrils reported increase, decrease, or no change with aging, perhaps due to the differences in physical activity, diet, and other factors. This study examined physical performance and contractile characteristics of myofibrils of vastus lateralis (VL) muscle in young adult and old African green vervet monkeys. Animals were offered the same diet and lived in the same enclosures during development, so we were able to examine skeletal muscle function in vivo and in vitro with fewer potential confounding factors than are typical in human research studies. Fiber atrophy alone did not account for the age-related differences in specific force and maximal power output. Regression modeling used to identify factors contributing to lower fiber force revealed that age is the strongest predictor. Our results support a detrimental effect of aging on the intrinsic force and power generation of myofilament lattice and physical performance in vervet monkeys.
authors.affiliation: Department of Internal Medicine, Gerontology, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
authors.forename: Seung Jun
authors.initials: SJ
authors.lastname: Choi
authors.forename: Carol A
authors.initials: CA
authors.lastname: Shively
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Register
authors.forename: Xin
authors.initials: X
authors.lastname: Feng
authors.forename: John
authors.initials: J
authors.lastname: Stehle
authors.forename: Kevin
authors.initials: K
authors.lastname: High
authors.forename: Edward
authors.initials: E
authors.lastname: Ip
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Kritchevsky
authors.forename: Barbara
authors.initials: B
authors.lastname: Nicklas
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Delbono
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D002522:Chlorocebus aethiops; D005260:Female; D007551:Isotonic Contraction / Q000502:physiology; D016014:Linear Models; D018485:Muscle Fibers, Skeletal / Q000473:pathology / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D009133:Muscular Atrophy / Q000473:pathology; D009210:Myofibrils / Q000473:pathology / Q000502:physiology; D018995:Myosin Heavy Chains / Q000378:metabolism; D010805:Physical Conditioning, Animal
chemical_list: D018995:Myosin Heavy Chains