Dietary polyunsaturated fatty acids and aging modulate glutathione-related antioxidants in rat liver.
The effects of dietary polyunsaturated fatty acids (PUFA) on the age-dependent changes in liver glutathione antioxidant system were investigated in male Wistar rats fed diets supplying either balanced amounts of linoleic acid and alpha-linolenic acids (control) or deficient in alpha-linolenic acid [n-3) deficient]. The animals were studied at the age of 6 or 24 mo. Glutathione antioxidative metabolism was markedly affected by aging. Cytosolic concentration of reduced glutathione (GSH) was lower (P < 0.01), whereas that of oxidized glutathione (GSSG) as well as the GSSG:GSH ratio were greater (P<0.001) in the 24-mo-old as compared with the 6-mo-old rats, regardless of the diet. Glutathione peroxidase activities were lower (P < 0.001) in 24-mo-old rats, though more markedly in those fed the control diet. The lipid composition of rat liver microsomal membranes was strongly modified by both diet and aging. The age-related changes mainly involved the polyunsaturated fatty acids. These results suggest that the nature of dietary PUFA and not only their degree of unsaturation affects the cellular glutathione-dependent antioxidant system and thus may modify the age-related changes in metabolic reactions.
D000375:Aging / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000032:analysis / Q000378:metabolism*; D001835:Body Weight; D004042:Dietary Fats, Unsaturated / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology* / Q000592:standards; D005954:Glucosephosphate Dehydrogenase / Q000032:analysis / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism / Q000502:physiology*; D005979:Glutathione Peroxidase / Q000032:analysis / Q000378:metabolism; D005980:Glutathione Reductase / Q000032:analysis / Q000378:metabolism; D008041:Linoleic Acids / Q000032:analysis; D008042:Linolenic Acids / Q000032:analysis; D050356:Lipid Metabolism; D008099:Liver / Q000033:anatomy & histology / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D008563:Membrane Lipids / Q000032:analysis; D008862:Microsomes, Liver / Q000737:chemistry; D009929:Organ Size; D010084:Oxidation-Reduction; D051381:Rats; D017208:Rats, Wistar; D013347:Subcellular Fractions
D000975:Antioxidants; D004042:Dietary Fats, Unsaturated; D005231:Fatty Acids, Unsaturated; D008041:Linoleic Acids; D008042:Linolenic Acids; D008563:Membrane Lipids; D005954:Glucosephosphate Dehydrogenase; D005979:Glutathione Peroxidase; D005980:Glutathione Reductase; D005978:Glutathione