title: Effect of dietary polyunsaturated/saturated fatty acid ratio and dietary vitamin E on lipid peroxidation in the rat.
abstract: The effects of the dietary ratio of polyunsaturated/saturated fatty acids (P/S) and dietary vitamin E on lipid peroxidation (LP) were examined to determine whether the vitamin E requirement is elevated by increased P/S in ratios comparable to those found in human diets. Twelve groups of male weanling rats (six/group) were fed purified diets containing 20% fat with P/S ratios of 0.38, 0.82 or 2.30. At each P/S level, groups of rats received either 0, 10, 40 or 100 IU vitamin E/kg diet supplied as all-rac-alpha-tocopherol. After the diets were fed for 16 wk, in vivo LP was assessed by measuring pentane in expired breath. Pentane levels were significantly elevated in rats fed 0 IU vitamin E at all P/S levels. Both 40 and 100 IU vitamin E decreased pentane production to minimal levels for all P/S groups. Liver malondialdehyde levels and in vitro spontaneous red blood cell hemolysis results also indicated a significant effect of vitamin E in reducing in vitro LP, but no overall effect of P/S. Testicular and epididymal histology showed no effect of dietary P/S on the vitamin E requirement. These data demonstrated 40 IU vitamin E to be adequate for maximal inhibition of LP at the P/S levels tested and indicated that these levels of dietary P/S had no significant impact on the vitamin E requirement for the growing rat.
mesh_terms: D000818:Animals; D001835:Body Weight; D001944:Breath Tests; D002849:Chromatography, Gas; D004041:Dietary Fats / Q000378:metabolism / Q000494:pharmacology*; D004822:Epididymis / Q000187:drug effects; D005227:Fatty Acids / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D006461:Hemolysis; D008054:Lipid Peroxides / Q000037:antagonists & inhibitors; D008099:Liver / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000096:biosynthesis; D009751:Nutritional Requirements; D010420:Pentanes / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D013737:Testis / Q000187:drug effects; D014810:Vitamin E / Q000494:pharmacology*
chemical_list: D004041:Dietary Fats; D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D008054:Lipid Peroxides; D010420:Pentanes; D014810:Vitamin E; C033353:pentane; D008315:Malondialdehyde