Hypocholesterolemic effect of ursodeoxycholylcysteic acid in hamsters fed a high cholesterol diet.

We studied the effect of feeding ursodeoxycholylcysteic acid, the cysteic acid conjugated analog of ursodeoxycholyltaurine, on serum and liver cholesterol levels and on intestinal absorption of cholesterol and bile salts in hamsters. Addition of ursodeoxycholylcysteic acid to the cholesterol-enriched diet reduced the elevation of serum and liver cholesterol levels caused by feeding cholesterol. However, supplementation with ursodeoxycholylcysteic acid to the standard diet did not show any significant change in serum and liver cholesterol levels. Administration of ursodeoxycholylcysteic acid caused a decrease in dietary cholesterol absorption but did not interfere with the ileal transport of endogenous bile salts. Hence the hypocholesterolemic activity of dietary ursodeoxycholylcysteic acid is thought to be the effect on intestinal absorption of cholesterol but not to be the interruption of the enterohepatic circulation of bile salts.