NDLI: Age-related structural alterations in human skeletal muscle fibers and mitochondria are sex specific: relationship to single-fiber function.

Content Provider	World Health Organization (WHO)-Global Index Medicus
Author	Callahan, Damien M. Bedrin, Nicholas G. Subramanian, Meenakumari Berking, James Ades, Philip A. Toth, Michael J. Miller, Mark S.
Description	Author Affiliation: Callahan DM ( Department of Medicine, University of Vermont, Burlington, Vermont); Bedrin NG ( Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont.); Subramanian M ( Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont.); Berking J ( Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont.); Ades PA ( Department of Medicine, University of Vermont, Burlington, Vermont); Toth MJ ( Department of Medicine, University of Vermont, Burlington, Vermont); Miller MS ( Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, Vermont Mark.Miller@uvm.edu.)
Abstract	Age-related loss of skeletal muscle mass and function is implicated in the development of disease and physical disability. However, little is known about how age affects skeletal muscle structure at the cellular and ultrastructural levels or how such alterations impact function. Thus we examined skeletal muscle structure at the tissue, cellular, and myofibrillar levels in young (21-35 yr) and older (65-75 yr) male and female volunteers, matched for habitual physical activity level. Older adults had smaller whole muscle tissue cross-sectional areas (CSAs) and mass. At the cellular level, older adults had reduced CSAs in myosin heavy chain II (MHC II) fibers, with no differences in MHC I fibers. In MHC II fibers, older men tended to have fewer fibers with large CSAs, while older women showed reduced fiber size across the CSA range. Older adults showed a decrease in intermyofibrillar mitochondrial size; however, the age effect was driven primarily by women (i.e., age by sex interaction effect). Mitochondrial size was inversely and directly related to isometric tension and myosin-actin cross-bridge kinetics, respectively. Notably, there were no intermyofibrillar or subsarcolemmal mitochondrial fractional content or myofilament ultrastructural differences in the activity-matched young and older adults. Collectively, our results indicate age-related reductions in whole muscle size do not vary by sex. However, age-related structural alterations at the cellular and subcellular levels are different between the sexes and may contribute to different functional phenotypes in ways that modulate sex-specific reductions in physical capacity with age.
File Format	HTM / HTML
ISSN	87507587
e-ISSN	15221601
DOI	10.1152/japplphysiol.01362.2013
Journal	Journal of Applied Physiology
Issue Number	12
Volume Number	116
Language	English
Publisher	American Physiological Society
Publisher Date	2014-06-15
Publisher Place	United States
Access Restriction	Open
Subject Keyword	Discipline Physiology Aging Physiology Mitochondria Muscle Fibers, Skeletal Actins Metabolism Motor Activity Myosin Heavy Chains Research Support, N.i.h., Extramural
Content Type	Text
Resource Type	Article
Subject	Physiology Physiology (medical) Sports Science

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

Age-related structural alterations in human skeletal muscle fibers and mitochondria are sex specific: relationship to single-fiber function

Age-related slowing of myosin actin cross-bridge kinetics is sex specific and predicts decrements in whole skeletal muscle performance in humans.

Improvements in whole muscle and myocellular function are limited with high-intensity resistance training in octogenarian women.

Aerobic exercise training induces skeletal muscle hypertrophy and age-dependent adaptations in myofiber function in young and older men.

Inactivity, age, and exercise: single-muscle fiber power generation

Chronic disuse and skeletal muscle structure in older adults: sex-specific differences and relationships to contractile function.

Single muscle fiber contractile properties of young competitive distance runners.

MECHANISMS UNDERLYING SKELETAL MUSCLE WEAKNESS IN HUMAN HEART FAILURE: ALTERATIONS IN SINGLE FIBER MYOSIN PROTEIN CONTENT AND FUNCTION

Muscle fiber size and function in elderly humans: a longitudinal study.

Age-related structural alterations in human skeletal muscle fibers and mitochondria are sex specific: relationship to single-fiber function.

Similar Documents

Age-related structural alterations in human skeletal muscle fibers and mitochondria are sex specific: relationship to single-fiber function

Age-related slowing of myosin actin cross-bridge kinetics is sex specific and predicts decrements in whole skeletal muscle performance in humans.

Improvements in whole muscle and myocellular function are limited with high-intensity resistance training in octogenarian women.

Aerobic exercise training induces skeletal muscle hypertrophy and age-dependent adaptations in myofiber function in young and older men.

Inactivity, age, and exercise: single-muscle fiber power generation

Chronic disuse and skeletal muscle structure in older adults: sex-specific differences and relationships to contractile function.

Single muscle fiber contractile properties of young competitive distance runners.

MECHANISMS UNDERLYING SKELETAL MUSCLE WEAKNESS IN HUMAN HEART FAILURE: ALTERATIONS IN SINGLE FIBER MYOSIN PROTEIN CONTENT AND FUNCTION

Muscle fiber size and function in elderly humans: a longitudinal study.

Age-related structural alterations in human skeletal muscle fibers and mitochondria are sex specific: relationship to single-fiber function.