Abstract
We studied the effect of a bean diet on biliary lipid secretion, serum cholesterol concentration, and hepatic cholesterol metabolism in the rat. Rats fed a bean diet for 10-12 days had increased biliary cholesterol output and molar percentage by 300% and 200%, respectively, compared to rats fed an isocaloric and isoprotein casein diet. Biliary phospholipid output increased 180%. Bile flow and biliary bile salt output remained in the normal range. Total serum and VLDL cholesterol concentration significantly decreased 27% and 50%, respectively, in the rats fed the bean diet. Hepatic cholesterogenesis was increased 170% in the bean-fed animals. The relative contribution of newly synthesized hepatic cholesterol to total biliary cholesterol increased 200%, and that of endogenous origin only 50%. These results suggested that newly synthesized hepatic cholesterol was preferentially channelled to the biliary cholesterol secretory pathway in bean-fed rats. Although hepatic cholesteryl ester concentration increased 240%, the incorporation of [14C]oleate into hepatic cholesteryl esters was significantly decreased by 30% in isolated hepatocytes of bean-fed animals. These results were consistent with the possibility that the availability of hepatic free cholesterol for biliary secretion was increased in the bean-fed animals. This study demonstrates that bean intake has a profound effect on the metabolic channelling and compartmentalization of hepatic cholesterol, resulting in a significant decrease in total serum and very low density lipoprotein cholesterol concentrations and a high biliary cholesterol output.
Highlights
We studied the effect of a bean diet on biliary lipid secretion, serum cholesterol concentration, and hepatic cholesterol metabolism in the rat
Supplementary key words biliary cholesterol * hepatic cholesterogenesis serum cholesterol beans. Recent studies from this laboratory indicate that a legume diet, beans, significantly increases biliary cholesterol saturation and decreases total serum cholesterol and low density lipoprotein (LDL) cholesterol concentration in young Chilean men [1]
Biliary phospholipid output increased by 178%.Biliary cholesterol output and the cholesterolmolar percentage increased by 294% and 219%, respectively
Summary
Taurocholate, hydroxysteroid dehydrogenase, a-cellulose, Metrizamide, DL-methionine, and cholesterol were purchased from Sigma Chemical Co. Acute depletion of the bile salt pool was obtained by ligating the ileal and caecal blood vessels and perfusing the small intestine from the duodenum to the ileum with Krebs-bicarbonate buffer at 37OC for a period of 30 min at a rate of 3 ml/min This procedure decreases the rate of biliary bile salt output by approximately one order of magnitude compared with the initial rates [5]. The best curve fitting for the experimental data was a nonlinear regression of the form of the rectangular hyperbola y-=ax/b + x for the relationship bile salts-cholesterol and bile salts-phospholipid In this equation “a” represents the maximal theoretical output of biliary lipid obtained with a specific diet. Blood was collected by aortic puncture and plasma was obtained after centrifugation in sealed tubes for determination of water specific activity. Electrophoretic migration of intact lipoprotein fractions was done on cellulose-acetate paper, pH 8.6, according to the method of Kohn [13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
