Fecal bile acid excretion and liver cholesterol synthesis after sucralfate and cholestyramine administration in the rat

The effect of sucralfate on serum lipids and lipoproteins in normal volunteers [corrected]

Sucralfate is used in the treatment and prophylaxis of peptic ulcer disease. One possible mechanism of action is the binding of bile acids. Because the absorption of dietary fat and cholesterol is dependent on the presence of bile acids in the small intestines, sucralfate therapy may produce changes in serum lipoprotein composition qualitatively similar to bile acid sequestrants, such as cholestyramine, which reduce serum cholesterol levels. Although changes in total serum cholesterol have not been reported in sucralfate efficacy studies, the effect of sucralfate on serum lipoprotein composition has not been specifically addressed. The purpose of this study was to prospectively examine the effect of sucralfate on serum lipids and lipoproteins in normal volunteers. Eight healthy volunteers (six men, two women) were recruited for this 10-week study. Drugs known to affect cholesterol levels were not permitted before or during the study. Diet composition during the study period was unaltered from before the study. Subjects took 1 g sucralfate orally 1 hour before meals and at bedtime (four times a day) for 8 weeks, followed by a 2-week washout period. Fasting blood samples were obtained at baseline and weekly, and were analyzed for serum total and HDL cholesterol and for triglycerides. Levels of LDL cholesterol were estimated. After eight weeks of sucralfate, HDL cholesterol increased from baseline by 2.5 mg/dL (6.6%, from 37.6 +/- 9.5 to 40.1 +/- 8.69 mg/dL), and LDL cholesterol decreased by 7.6 mg/dL (6.4%, from 134 +/- 28.1 to 125.4 +/- 34.1). Total cholesterol decreased by 3.5 mg/dL (1.8%, from 192.9 +/- 34.3 to 189.4 +/- 37.2 mg/dL.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of the interruption of enterohepatic circulation of bile acids by cholestyramine on apolipoprotein gene expression in the rat

The aim of the study was to assess how the interruption of enterohepatic circulation may affect the regulation of apolipoprotein synthesis. For this purpose, apolipoprotein mRNA levels were measured in the liver and small intestine of male Wistar rats fed for 3 weeks diets with or without cholestyramine (5% w/w). In order to modulate intestinal lipid flux, we used diets with 2 or 10% lipid content. Cholestyramine treatment decreased plasma triglyceride and cholesterol concentrations (by 63% and 32%, respectively) in rats fed 10% corn oil containing diet but had no significant effect on plasma lipids in rats fed a low-fat diet. Plasma apo B and apo A-IV concentrations were lowered by cholestyramine treatment in both 10 and 2% oil fed groups; however plasma apo E concentration was only affected in rats receiving 10% corn oil in the diet. Cholestyramine treatment had no significant effect on plasma apo A-I concentration. Hepatic apo B, apo E and apo A-IV mRNA levels were similar among dietary groups. Cholestyramine administration caused an increase in hepatic apo A-I mRNA level only in rats fed low-fat diet. In the intestine cholestyramine treatment decreased apolipoprotein mRNA levels in jejunum but had a few effect on apolipoprotein mRNA levels in ileum. These experiments have shown that long-term decrease in the intraluminal availability of bile acids may alter not only lipid and lipoprotein metabolism but also the regulation of apolipoprotein synthesis.