Effect of cholesterol, cholic acid and cholestyramine administration on the intestinal mRNA expressions related to cholesterol and bile acid metabolism in the rat
Version of Record online: 13 MAY 2007
Journal of Gastroenterology and Hepatology
Volume 22, Issue 11, pages 1832–1837, November 2007
How to Cite
Kamisako, T., Ogawa, H. and Yamamoto, K. (2007), Effect of cholesterol, cholic acid and cholestyramine administration on the intestinal mRNA expressions related to cholesterol and bile acid metabolism in the rat. Journal of Gastroenterology and Hepatology, 22: 1832–1837. doi: 10.1111/j.1440-1746.2007.04910.x
- Issue online: 2 OCT 2007
- Version of Record online: 13 MAY 2007
- Accepted for publication 4 December 2006.
- liver X receptor α;
- multidrug resistance associated protein 2;
- multidrug resistance associated protein 3;
- small heterodimer partner
Background and Aim: To evaluate the importance of cholesterol and bile acid concentrations in the intestinal lumen to cholesterol homeostasis, we investigated the effect of cholesterol-, bile salt- or cholestyramine-administration on the regulation of intestinal mRNA related to cholesterol and bile acid metabolism.
Methods: Male Wistar rats fed on standard laboratory chow (AIN-93) were allocated into four experimental groups: (i) control group; (ii) cholesterol group (CH), which was fed cholesterol in diet (2% [w/w]) for 14 days; (iii) cholic acid (CA) group, which was fed CA in diet (1% [w/w]) for 14 days; (iv) cholestyramine (CT) group, which was fed CT in diet (5% [w/w]) for 14 days. Blood, liver and small intestine were obtained after 14 days. Serum lipids and bile acids were measured by colorimetric assays, and hepatic and intestinal mRNA relating to lipid and bile acid metabolism was studied by reverse transcription–polymerase chain reaction.
Results: Intestinal ABCG8, liver X receptor α, small heterodimer partner (SHP) and sterol regulatory element binding protein 1c (SREBP-1c) mRNA expressions were markedly increased in the CH group. Intestinal multidrug resistance associated protein (MRP) 2 and MRP3 mRNA expressions were markedly increased in the CA group. In the CT group intestinal MRP2, ABCG5, ABCG8, SHP and SREBP-1c mRNA expressions were markedly decreased.
Conclusion: The bile acid availability in the intestinal lumen alters the expression of various intestinal mRNA relating to not only bile acid metabolism, but also lipid metabolism. Though the mechanism of the intestinal SHP elevation is unclear, cholesterol feeding may affect the intestinal bile acid metabolism via intestinal SHP expression.