| Content Provider |
World Health Organization (WHO)-Global Index Medicus |
| Author |
Callahan, Damien M. Tourville, Timothy W. Miller, Mark S. Hackett, Sarah B. Sharma, Himani Cruickshank, Nicholas C. Slauterbeck, James R. Savage, Patrick D. Ades, Philip A. Maughan, David W. Beynnon, Bruce D. Toth, Michael J. |
| Description |
Author Affiliation: Callahan DM ( Department of Medicine, College of Medicine, University of Vermont, Burlington, Vermont); Tourville TW ( Department of Orthopaedics and Rehabilitation, College of Medicine, University of Vermont, Burlington, Vermont.); Miller MS ( Department of Molecular Physiology and Biophysics, College of Medicine, University of Vermont, Burlington, Vermont); Hackett SB ( Department of Medicine, College of Medicine, University of Vermont, Burlington, Vermont); Sharma H ( Department of Medicine, College of Medicine, University of Vermont, Burlington, Vermont); Cruickshank NC ( Department of Medicine, College of Medicine, University of Vermont, Burlington, Vermont); Slauterbeck JR ( Department of Orthopaedics and Rehabilitation, College of Medicine, University of Vermont, Burlington, Vermont.); Savage PD ( Department of Medicine, College of Medicine, University of Vermont, Burlington, Vermont); Ades PA ( Department of Medicine, College of Medicine, University of Vermont, Burlington, Vermont); Maughan DW ( Department of Molecular Physiology and Biophysics, College of Medicine, University of Vermont, Burlington, Vermont); Beynnon BD ( Department of Orthopaedics and Rehabilitation, College of Medicine, University of Vermont, Burlington, Vermont.); Toth MJ ( Department of Medicine, College of Medicine, University of Vermont, Burlington, Vermont) |
| Abstract |
In older adults, we examined the effect of chronic muscle disuse on skeletal muscle structure at the tissue, cellular, organellar, and molecular levels and its relationship to muscle function. Volunteers with advanced-stage knee osteoarthritis (OA, n = 16) were recruited to reflect the effects of chronic lower extremity muscle disuse and compared with recreationally active controls (n = 15) without knee OA but similar in age, sex, and health status. In the OA group, quadriceps muscle and single-fiber cross-sectional area were reduced, with the largest reduction in myosin heavy chain IIA fibers. Myosin heavy chain IIAX fibers were more prevalent in the OA group, and their atrophy was sex-specific: men showed a reduction in cross-sectional area, and women showed no differences. Myofibrillar ultrastructure, myonuclear content, and mitochondrial content and morphology generally did not differ between groups, with the exception of sex-specific adaptations in subsarcolemmal (SS) mitochondria, which were driven by lower values in OA women. SS mitochondrial content was also differently related to cellular and molecular functional parameters by sex: greater SS mitochondrial content was associated with improved contractility in women but reduced function in men. Collectively, these results demonstrate sex-specific structural phenotypes at the cellular and organellar levels with chronic disuse in older adults, with novel associations between energetic and contractile systems. |
| File Format |
HTM / HTML |
| ISSN |
03636143 |
| e-ISSN |
15221563 |
| DOI |
10.1152/ajpcell.00014.2015 |
| Journal |
American Journal of Physiology - Cell Physiology |
| Issue Number |
11 |
| Volume Number |
308 |
| Language |
English |
| Publisher |
American Physiological Society |
| Publisher Date |
2015-06-01 |
| Publisher Place |
United States |
| Access Restriction |
Open |
| Subject Keyword |
Discipline Cell Biology Knee Physiopathology Muscle Contraction Muscle Fibers, Skeletal Pathology Muscular Atrophy Osteoarthritis, Knee Quadriceps Muscle Case-control Studies Gene Expression Mitochondria Metabolism Ultrastructure Complications Myosin Heavy Chains Genetics Protein Isoforms Sex Factors Research Support, N.i.h., Extramural |
| Content Type |
Text |
| Resource Type |
Article |
| Subject |
Cell Biology Physiology |
