Effect of dietary coconut oil and casein and megadoses of vitamin A or C on tissue lipid peroxidation and hemolysis in vitamin E deficiency.

Male rats fed on pellet diet to an average weight of 105 g were placed on a vitamin E deficient diet containing 20% coconut oil for a period of 12 weeks at two dietary protein levels, 20% and 10% casein. Rats on 20% casein diet showed a definite weight loss but not so at the 10% casein level. A marked increase in the liver in vitro lipid peroxidation was observed at both protein levels. Feeding of retinyl palmitate at 100,000 IU/100 g body weight for 4 consecutive days inhibited the liver, brain and kidney in vitro peroxidation; megadoses of ascorbic acid produced less inhibition of the liver peroxidation, but the same degree of inhibition for brain and kidney peroxidation as in vitamin A loaded rats. Both dietary palmitate or ascorbic acid. Acetylcholine esterase and ATPase, two of the membrane enzymes of erythrocytes, were depressed in all the groups. The glutathione content of erythrocytes was increased in rats given ascorbic acid. In all the groups the higher dietary protein levels produced greater loss of body and tissue weights. It is concluded vitamin E deficient diet supplemented with dietary coconut oil (saturated fat) induces increased in vitro lipid peroxidation and oxidative lysis of erythrocytes and that megadoses of vitamin A or C suppress the in vitro lipid peroxidation but enhance the lysis.