Effect of exercise training on tissue vitamin E and ubiquinone content.
Endurance exercise training led to an adaptive increase in the ubiquinone content and cytochrome c reductase activity of red quadriceps and soleus muscles and adipose tissues, but not of cardiac or white quadriceps muscle. These findings are consistent with the well-known positive adaptation of skeletal muscle mitochondria to endurance training. However, there was no concomitant increase in the vitamin E content of tissues, which showed an increase in mitochondrial content. Since ubiquinone is located in the mitochondrial inner membrane and the major pool of vitamin E is also associated with mitochondrial membranes, the results suggest that training causes a substantial decrease in vitamin E concentration in the proliferating muscle mitochondrial membranes, thus depleting muscle mitochondria of their major lipid antioxidant. Since vitamin E is the major cellular, lipid-soluble, chain-breaking antioxidant, these findings indicate increased free radical reactions in the tissues of exercising animals.
Gohil
K
K
Department of Physiology and Anatomy, University of California, Berkeley 94720.
Rothfuss
L
L
Lang
J
J
Packer
L
L
D002001:Adipose Tissue, Brown / Q000378:metabolism; D000818:Animals; D005260:Female; D008099:Liver / Q000378:metabolism; D009132:Muscles / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D010084:Oxidation-Reduction; D010806:Physical Education and Training; D051381:Rats; D011919:Rats, Inbred Strains; D013384:Succinate Cytochrome c Oxidoreductase / Q000378:metabolism; D014451:Ubiquinone / Q000378:metabolism*; D014810:Vitamin E / Q000378:metabolism*
D014451:Ubiquinone; D014810:Vitamin E; D013384:Succinate Cytochrome c Oxidoreductase