Influence of Dietary Fiber on Aortic Sudanophilia in Vervet Monkeys

Abstract

Vervet monkeys were fed a cholesterol-free, semipurified diet containing 40% sucrose, 25% casein, 14% coconut oil and 15% fiber for 23 weeks. The fibers used were cellulose, wheat straw or alfalfa. Serum lipid and lipoprotein levels were highest in the monkeys fed the cellulose-containing diet. Liver lipids were slightly higher in the cellulose-fed monkeys. The ratio of endogenous to exogenous cholesterol was estimated using isotopically labeled sterol and sterol precursor and found to be similar in all three groups. The levels of endogenous or exogenous cholesterol in the serum and liver of alfalfa-fed monkeys were lower than the levels in the other two groups, which were similar. The ratio of exogenous to endogenous cholesterol in the feces was highest in the monkeys fed alfalfa. Monkeys fed alfalfa exhibited the lowest lithogenic index. Cholesterol 7α-hydroxylase activity was highest in livers of monkeys fed wheat straw. The data suggest that alfalfa inhibits absorption and reabsorption of cholesterol more than wheat straw or cellulose. Monkeys fed cellulose exhibited more severe aortic sudanophilia than those fed the other two fibers.