Effect of coenzyme Q(10) and alpha-tocopherol content of mitochondria on the production of superoxide anion radicals.
The effects of coenzyme Q(10) (CoQ(10)) and alpha-tocopherol on the rate of mitochondrial superoxide anion radical (O2(./-)) generation were examined in skeletal muscle, liver, and kidney of 24-month-old mice. Mice were orally administered alpha-tocopherol (200 mg.kg(-1).day(-1)) alone, CoQ(10) (123 mg.kg(-1).day(-1)) alone, or the two together for 13 wk. Administration of alpha-tocopherol resulted in an approximately sevenfold elevation of mitochondrial alpha-tocopherol content. Intake of CoQ(10) alone caused an approximately fivefold increase in CoQ content (CoQ(9) and/or CoQ(10)) and alpha-tocopherol of mitochondria. The rate of (O2(./-)) generation by submitochondrial particles (SMPs) was inversely related to their alpha-tocopherol content but unrelated to CoQ content. Experimental in vitro augmentation of SMPs with varying amounts of alpha-tocopherol caused an up to approximately 50% decrease in the rate of O2(./-) generation. Similar in vitro augmentations of SMPs with CoQ(10) had previously been found to have no effect on the rate of O2(./-) generation The CoQ(10)-induced elevation of alpha-tocopherol in the present study was inferred to be due to a 'sparing/regeneration' by CoQ. Results indicate the involvement of alpha-tocopherol in the elimination of mitochondrially generated O2(./-)
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Department of Biological Sciences, Southern Methodist University, Dallas, Texas 75275, USA.
Sohal
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D000818:Animals; D002417:Cattle; D003067:Coenzymes; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D010101:Oxygen Consumption; D013367:Submitochondrial Particles / Q000187:drug effects / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D014810:Vitamin E / Q000008:administration & dosage / Q000378:metabolism*
D003067:Coenzymes; D013481:Superoxides; D014451:Ubiquinone; D014810:Vitamin E; C024989:coenzyme Q10