Effect of age and caloric restriction on coenzyme Q and alpha-tocopherol levels in the rat.
Alterations in the amount of coenzyme Q and alpha-tocopherol during aging and in response to 40% reduction in caloric intake were determined in homogenates and mitochondria of liver, heart and kidney of the rat. A comparison among 4-, 19- and 28-month-old ad libitum fed (AL) rats indicated an age-related loss in the amount of CoQ9 and alpha-tocopherol in mitochondria of all the three tissues. Depletion of alpha-tocopherol, but not of CoQ, was also detectable in tissue homogenates, apparently due to the preferential sequestration of CoQ in the mitochondrial fraction. Comparison of 19-month-old AL and calorically restricted (CR) rats indicated that CR elevates the level of mitochondrial CoQ, but greatly diminishes the alpha-tocopherol content. Activity of DT-diaphorase, a quinone reductase, increased with age as well as in response to CR. Altogether, results are interpreted to suggest that the widely observed age-related increase in mitochondrial oxidative damage may be associated with depletion of CoQ and alpha-tocopherol, which are known to act in tandem to prevent oxidative damage to membranes.
Department of Molecular Pharmacology and Toxicology, University of Southern California, 1985 Zonal Avenue, Los Angeles, CA 90089, USA.
Sergey
S
Kamzalov
Rajindar S
RS
Sohal
D000375:Aging; D000818:Animals; D015415:Biomarkers / Q000032:analysis; D031204:Caloric Restriction; D007668:Kidney / Q000737:chemistry; D008099:Liver / Q000737:chemistry; D008928:Mitochondria / Q000737:chemistry*; D009206:Myocardium / Q000737:chemistry; D051381:Rats; D011916:Rats, Inbred F344; D014451:Ubiquinone / Q000032:analysis* / Q000097:blood; D024502:alpha-Tocopherol / Q000032:analysis* / Q000097:blood
D015415:Biomarkers; D014451:Ubiquinone; D024502:alpha-Tocopherol