The effect of spices on cholesterol 7 alpha-hydroxylase activity and on serum and hepatic cholesterol levels in the rat.

The effect of feeding curcumin, capsaicin, ginger, mustard, black pepper and cumin on cholesterol and bile acid metabolism was studied in rats. The activity of hepatic cholesterol-7 alpha-hydroxylase, the rate-limiting enzyme of bile acid biosynthesis, was significantly elevated in curcumin (turmeric), capsaicin (red pepper), ginger and mustard treated animals. The enzyme activity was comparable to controls in black pepper and cumin fed rats. Serum and liver microsomal cholesterol contents were significantly higher in the curcumin and capsaicin treated animals. Thus, this study has suggested that the spices--turmeric, red pepper, ginger and mustard can stimulate the conversion of cholesterol to bile acids, an important pathway of elimination of cholesterol from the body. However, simultaneous stimulation of cholesterol synthesis by the spice principles--curcumin and capsaicin suggests that there may not be any significant contribution of stimulation of bile acid biosynthesis to the hypocholesterolemic action of these spices, and the latter action may solely be due to interference with exogenous cholesterol absorption.