Comparison of the hepatic clearances of campesterol, sitosterol, and cholesterol in healthy subjects suggests that efflux transporters controlling intestinal sterol absorption also regulate biliary secretion. Issue 6 (1st December 2002)

• Record Type: Journal Article
• Authors: Sudhop, T; Sahin, Y; Lindenthal, B; Hahn, C; Lüers, C; Berthold, H K; von Bergmann, K
• Is Part Of: Gut. Volume 51:Issue 6(2002)
• Page Start: 860
• Page End: 863
• Publication Date: 2002-12-01
• Subjects: plant sterols -- cholesterol -- campesterol -- sitosterol -- biliary excretion -- hepatic clearance -- ABCG5/8; Gastroenterology -- Periodicals; 616.33
• DOI: 10.1136/gut.51.6.860
• Languages: English
• ISSNs: 0017-5749

Abstract

Abstract : Background: Recently identified ABCG5/8 transporters are responsible in part for the different absorption rates of campesterol, sitosterol, and cholesterol. These transporters are also expressed in the liver and might regulate biliary sterol secretion. Aims: This study was therefore conducted to determine the biliary secretion rates and hepatic clearances of campesterol, sitosterol, and cholesterol. Subjects: Six healthy, male volunteers. Methods: Deuterium labelled sitosterol and campesterol, and unlabelled sitostanol were constantly infused together with a liquid formula using a duodenal perfusion technique. Biliary secretion and hepatic clearance rates were calculated from hourly bile and plasma samples. Results: Plasma concentrations of cholesterol, campesterol, and sitosterol averaged 167.5 (50) mg/dl (SD), 0.50 (0.22) mg/dl, and 0.30 (0.10) mg/dl, respectively. Sitosterol showed a significantly higher biliary secretion rate (1.23 (0.87) mg/h) than campesterol (0.76 (0.54) mg/h, p=0.0321), but both plant sterols had significantly lower biliary secretion rates compared with cholesterol (47.7 (17.5) mg/h; p=0.001 for both). Hepatic clearance of cholesterol (0.31 (0.18) dl/h) was significantly lower compared with campesterol (2.11 (2.51) dl/h) and sitosterol (4.97 (4.70) dl/h; p=0.028 for both), and the clearance of campesterol was significant lower compared with sitosterol (p=0.028). Conclusion: The observed inverse relation between hepatic clearance and known intestinal absorption of cholesterol, campesterol, and sitosterol supports the hypothesis that the ABCG5/8 transporters regulating intestinal sterol absorption might also be involved in biliary sterol excretion.