Depression of the Lecithin-Cholesterol Acyltransferase Reaction in Vitamin E-Deficient Monkeys,

Vitamin E deficiency in two species of monkeys reduced the esterification of cholesterol by the plasma lecithin-cholesterol acyltransferase reaction. The reduction was greatest in animals fed a diet rich in polyunsaturated fat and stripped of vitamin E. Concomitant to this in vitro measure was a depression in the concentration of circulating polyunsaturated fatty acid cholesteryl esters. Since the plasma lecithin-cholesterol acyltransferase reaction has been shown to be dependent upon sulfhydryl groups on the enzyme, it is proposed that the observed reduction in esterification of cholesterol by plasma from vitamin E-deficient monkeys is due to alteration of these sulfhydryl sites. A similar reduction in the plasma lecithin-cholesterol acyltransferase reaction has been shown to occur during exposure in vivo to a pure oxygen atmosphere, a condition predisposing to lipid peroxidation. Author