出版社：American Society for Biochemistry and Molecular Biology
摘要：Oxidized cholesterol is present in significant quantities inthe typical Western diet. When ingested, oxidized cholesterolis absorbed by the small intestine and incorporated into bothchylomicrons and LDL, resulting in LDL that is more susceptibleto further oxidation. Feeding studies in animal models and epidemiologicalstudies in humans have suggested that oxidized cholesterol inthe diet increases the development of atherosclerosis. In thisstudy, we determined the effect of ezetimibe, a drug that inhibitssmall intestinal absorption of cholesterol, on the levels ofoxidized cholesterol in the serum after a test meal containingoxidized cholesterol. We demonstrate that ezetimibe, 10 mg perday for 1 month, markedly reduced the levels (50% decrease)of oxidized cholesterol in the serum after feeding a test mealcontaining either -epoxy cholesterol or 7-keto cholesterol,two of the predominant oxidized cholesterols found in the diet.Moreover, the decrease in oxidized cholesterol in the serumwas attributable to a decrease in the incorporation of dietaryoxidized cholesterol into both chylomicrons and LDL. Becausethere was no decrease in postprandial triglyceride levels, weconclude that this decrease in oxidized cholesterol levels inthe serum is attributable to decreased absorption and not toenhanced clearance. Whether this decrease in oxidized cholesterolabsorption prevents or delays the development of atherosclerosisremains to be determined.Supplementary key words oxidized lipoproteins • diet • cholesterol absorption • -epoxy cholesterol • 7-keto cholesterol
-epoxy cholesterol or 7-keto cholesterol, two of the predominant oxidized cholesterols found in the diet. Moreover, the decrease in oxidized cholesterol in the serum was attributable to a decrease in the incorporation of dietary oxidized cholesterol into both chylomicrons and LDL. Because there was no decrease in postprandial triglyceride levels, we conclude that this decrease in oxidized cholesterol levels in the serum is attributable to decreased absorption and not to enhanced clearance. Whether this decrease in oxidized cholesterol absorption prevents or delays the development of atherosclerosis remains to be determined.
Supplementary key words oxidized lipoproteins • diet • cholesterol absorption • 
