Concentrations of cholestenoic acids in plasma from patients with reduced intestinal reabsorption of bile acids.

The concentrations of 3@-hydroxy-5-cholestenoic acid, 3~,7a-dihydroxy-5-cholestenoic acid, and 7a-hydroxy-3- oxo-4-cholestenoic acid were determined in plasma from pa- tients treated with cholestyramine or subjected to resection of the ileum or colon. The values were compared with those for con- jugated and unconjugated C24 bile acids. Patients with an intact ileum but without colon had normal levels of cholestenoic acids. Patients treated with cholestyramine or with ileal resection had elevated levels of 7a-hydroxy-3-oxo-4-cholestenoic acid (median values 189 and 233 ng/ml, respectively, compared to 85 ng/ml in controls). The levels of the other two Cz7 acids were normal in cholestyramine-treated and low in ileoresected patients and were positively correlated to each other but not to the 3-oxo-A' acid. There were no consistent correlations between the levels of Cz7 acids and those of conjugated or unconjugated Cp4 bile acids. The results indicate an increased formation of 7a-hydroxy-3-oxo-4-cholestenoic acid in subjects having a stimu- lated activity of cholesterol 7a-hydroxylase. -Axelson, M., B. Mork, A. Aly, G. Walldius, and J. Sjovall. Concentrations of cholestenoic acids in plasma from patients with reduced intesti- nal absorption of bile acids. J Lipid Res. 1989. 30 1883- 1887. 3-oxo-4-cholestenoic acids in plasma of patients with different liver diseases were reported (1). The concentra- tions were similar in patients with extrahepatic cholestasis and control subjects, indicating a difference in the pro- duction or hepatic handling of Cz7 and Cz9 bile acids. However, elevated levels, particularly of 7a-hydroxy-3- oxo-4-cholestenoic acid, were found in liver cirrhosis and there was a significant correlation between these levels and those of conjugated bile acids. This was suggested to result from a reduced hepatic clearance and to indicate that the liver plays an important role for the elimination or metabolism of the Cp7 acids in blood. In order to gain more information about the relationships between bile acid biosynthesis and the formation of the cholestenoic acids, we have now determined the levels of these acids in patients who have an apparently healthy liver but an im- paired bile acid absorption due to treatment with choles- tyramine or intestinal resection. The results provide indi- rect evidence for an involvement of the liver in the biosyn- thesis of the cholestenoic acids.