Journal
FREE RADICAL BIOLOGY AND MEDICINE
Volume 41, Issue 11, Pages 1719-1725Publisher
ELSEVIER SCIENCE INC
DOI: 10.1016/j.freeradbiomed.2006.09.008
Keywords
skeletal muscle myotubes; free radicals; superoxide; hydrogen peroxide; epifluorescence
Funding
- NIA NIH HHS [P01, AG20591] Funding Source: Medline
- Wellcome Trust [073263/Z/03/Z] Funding Source: Medline
Ask authors/readers for more resources
Increased amounts of reactive oxygen species (ROS) are generated by skeletal muscle during contractile activity, but their intracellular source is unclear. The oxidation of 2',7'-dichlorodihydrofluorescein (DCFH) was examined as an intracellular probe for reactive oxygen species in skeletal muscle myotubes derived from muscles of wild-type mice and mice that were heterozygous knockout for manganese superoxide dismutase (Sod2(+/-)), homozygous knockout for glutathione peroxidase I (GPx1(-/-)), or MnSOD transgenic overexpressors (Sod2-Tg). Myoblasts were stimulated to fuse and loaded with DCFH 5-7 days later. Intracellular DCF epifluorescence was measured and myotubes were electrically stimulated to contract for 15 min. Quiescent myotubes with decreased MnSOD or GPx1 showed a significant increase in the rate of DCFH oxidation whereas those with increased MnSOD did not differ from wild type. Following contractions, myotubes from all groups showed an equivalent increase in DCF fluorescence. Thus the oxidation of DCFH in quiescent skeletal muscle myotubes is influenced by the content of enzymes that regulate mitochondrial superoxide and hydrogen peroxide content. In contrast, the increase in DCFH oxidation following contractions was unaffected by reduced or enhanced MnSOD or absent GPx1, indicating that reactive oxygen species produced by contractions were predominantly generated by nonmitochondrial sources. (c) 2006 Published by Elsevier Inc.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available