Skip Navigation LinksHome > December 2012 - Volume 44 - Issue 12 > Reduced Satellite Cell Numbers with Spinal Cord Injury and A...
Medicine & Science in Sports & Exercise:
doi: 10.1249/MSS.0b013e3182667c2e
Basic Sciences

Reduced Satellite Cell Numbers with Spinal Cord Injury and Aging in Humans

VERDIJK, LEX B.1; DIRKS, MARLOU L.1; SNIJDERS, TIM1; PROMPERS, JEANINE J.2; BEELEN, MILOU1; JONKERS, RICHARD A. M.1,2; THIJSSEN, DICK H. J.3,4; HOPMAN, MARIA T. E.3; VAN LOON, LUC J. C.1

Collapse Box

Abstract

Introduction: Both sarcopenia and spinal cord injury (SCI) are characterized by the loss of skeletal muscle mass and function. Despite obvious similarities in atrophy between both models, differences in muscle fiber size and satellite cell content may exist on a muscle fiber type–specific level.

Methods: In the present study, we compared skeletal muscle fiber characteristics between wheelchair-dependent young males with SCI (n = 8, 32 ± 4 yr), healthy elderly males (n = 8, 75 ± 2 yr), and young controls (n = 8, 31 ± 3 yr). Muscle biopsies were collected to determine skeletal muscle fiber type composition, fiber size, and satellite cell content.

Results: Severe atrophy and a shift toward approximately 90% Type II muscle fibers were observed in muscle obtained from males with SCI. Muscle fiber size was substantially smaller in both the SCI (Types I and II fibers) and elderly subjects (Type II fibers) when compared with the controls. Satellite cell content was substantially lower in the wheelchair-dependent SCI subjects in both the Types I and II muscle fibers (0.049 ± 0.019 and 0.050 ± 0.005 satellite cells per fiber, respectively) when compared with the young controls (0.104 ± 0.011 and 0.117 ± 0.009 satellite cells per fiber, respectively). In the elderly, the number of satellite cells was lower in the Type II muscle fibers only (0.042 ± 0.005 vs 0.117 ± 0.009 satellite cells per fiber in the elderly vs young controls, respectively).

Conclusion: This is the first study to show that muscle fiber atrophy as observed with SCI (Types I and II fibers) and aging (Type II fibers) is accompanied by a muscle fiber type–specific reduction in satellite cell content in humans.

©2012The American College of Sports Medicine

Login

Article Tools

Share

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.

Connect With Us