Consequences of aging on mitochondrial respiratory chain enzymes in cultured human fibroblasts treated with ascorbate.
The activities of mitochondrial respiratory chain enzymes with and without ascorbate pretreatment were assayed in 10- to 20-week-old cultures of human fibroblasts. Aging was associated with a significant loss of respiratory chain enzyme activities. The presence of ascorbate in the medium reduced the rate of loss of these enzymes. Free radical-mediated injuries may also contribute to aging since the changes seen in respiratory chain enzyme activities are similar to those seen in oxidatively stressed cells. This study demonstrates an age-related decline in mitochondrial respiratory chain activity as well as a protective role for ascorbate in aging.
Sharma
P
P
Biochemical Genetics Laboratory, CPRI, London, Ont., Canada.
Rupar
C A
CA
Rip
J W
JW
D001205:Ascorbic Acid / Q000494:pharmacology*; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000502:physiology; D002950:Citrate (si)-Synthase / Q000378:metabolism; D004579:Electron Transport / Q000187:drug effects / Q000502:physiology*; D042963:Electron Transport Complex II; D014450:Electron Transport Complex III / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000201:enzymology; D005609:Free Radicals / Q000378:metabolism; D006801:Humans; D008297:Male; D008928:Mitochondria / Q000187:drug effects / Q000201:enzymology*; D009097:Multienzyme Complexes / Q000378:metabolism; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D010088:Oxidoreductases / Q000378:metabolism; D013385:Succinate Dehydrogenase / Q000378:metabolism
D005609:Free Radicals; D009097:Multienzyme Complexes; D010088:Oxidoreductases; D042963:Electron Transport Complex II; D013385:Succinate Dehydrogenase; D016660:NAD(P)H Dehydrogenase (Quinone); D003576:Electron Transport Complex IV; D002950:Citrate (si)-Synthase; D014450:Electron Transport Complex III; D001205:Ascorbic Acid