title: Vitamin A at pharmacologic doses ameliorates the membrane lipid peroxidation injury and testicular atrophy that occurs with chronic alcohol feeding in rats.
abstract: The interaction of ethanol (ETOH) with testicular subcellular membranes contributes, at least in part, to alcohol-induced gonadal dysfunction. Vitamin A reaches the testes via the circulation as the retinyl ester and is converted to the free alcohol (retinol) and then to the aldehyde (retinal); retinal is the form of the vitamin which is essential for normal spermato-genesis. Because retinol can function as a free radical scavenger, testicular mitochondria were evaluated for evidence of a protective role provided by supplemental dietary vitamin A on ETOH-induced alterations in testicular structure and function in rats. Lipid peroxidation was evaluated by measurement of malonaldehyde formation and glutathione content of the testes. Compared to isocalorically matched dextrimaltose-fed controls (ISO) receiving a modified vitamin A containing diet, rats fed the corresponding ETOH diet for 50 days had a reduced testes/body ratio (ETOH: 0.0114 +/- 0.0004 vs ISO: 0.0128 +/- 0.0004). Mitochondrial enriched extracts obtained from the testes of these ETOH-fed rats showed significant increases in malonaldehyde formation; moreover, glutathione levels were reduced in the testes of the alcohol-fed animals when compared to their isocaloric controls. In contrast, no evidence for testicular atrophy was present in ETOH-fed rats receiving a standard vitamin A enriched diet; moreover, such ETOH-fed rats had a reduced rate of malonaldehyde formation as compared to their respective controls. Similarly, glutathione levels were not depleted in the testes of the ETOH-fed rats receiving the vitamin A enriched diet. Taken together, these data suggest that lipid peroxidation is a consequence of ethanol metabolism which can be attenuated, at least in part, by vitamin A.
mesh_terms: D000818:Animals; D001284:Atrophy; D004032:Diet; D000431:Ethanol / Q000378:metabolism / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism; D008054:Lipid Peroxides / Q000378:metabolism*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013737:Testis / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D014801:Vitamin A / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D008054:Lipid Peroxides; D008563:Membrane Lipids; D014801:Vitamin A; D000431:Ethanol; D008315:Malondialdehyde; D005978:Glutathione