Hypocholesterolemic effect of 5 beta-cholane-3 alpha,7 beta,24-triol-24- sulfate in hamsters

We studied the effect of 5 beta-cholane-3 alpha,7 beta,24-triol-24-sulfate (UDC-O-sulfate) on ileal active transport of cholyltaurine, on hepatic cholesterol 7 alpha-hydroxylase activity, on serum and liver cholesterol levels, on intestinal absorption of cholesterol, and on bile salt composition of gallbladder bile in hamsters. Experiments using the everted gut sacs show that UDC-O-sulfate inhibits the ileal active transport of cholyltaurine. In experiments feeding the diets with either UDC-O-sulfate, cholesterol, or both to hamsters, the addition of UDC-O-sulfate to the cholesterol-enriched diet reduced the elevation of serum and liver cholesterol levels caused by cholesterol feeding. Supplementation with UDC-O-sulfate to the standard diet was likely to reduce serum and liver cholesterol levels. Cholesterol 7 alpha-hydroxylase activity was higher in the two UDC-O-sulfate supplemented groups than in the two corresponding groups, the standard diet group and the cholesterol enriched diet group, respectively. Addition of UDC-O-sulfate to the standard and cholesterol diets did not change intestinal absorption of cholesterol. The change of the bile salt composition in hamsters fed UDC-O-sulfate may also suggest that the bile alcohol sulfate inhibits the intestinal absorption of endogenous bile salts. Hence the hypocholesterolemic activity of dietary UDC-O-sulfate is thought to be the effect of the partial interruption of the enterohepatic circulation of endogenous bile salts.