Effect of bean intake on biliary lipid secretion and on hepatic cholesterol metabolism in the rat.
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.
Rigotti
A
A
Departamento de Gastroenterología, Facultad de Medicina, Pontificia Universidad Católica de Chile.
Marzolo
M P
MP
Ulloa
N
N
González
O
O
Nervi
F
F
D000818:Animals; D001646:Bile / Q000378:metabolism*; D001835:Body Weight; D002784:Cholesterol / Q000097:blood / Q000378:metabolism*; D002788:Cholesterol Esters / Q000378:metabolism; D004032:Diet; D007887:Fabaceae; D050356:Lipid Metabolism; D008074:Lipoproteins / Q000097:blood; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008297:Male; D010946:Plants, Medicinal; D051381:Rats; D011919:Rats, Inbred Strains; D014280:Triglycerides / Q000097:blood
D002788:Cholesterol Esters; D008074:Lipoproteins; D014280:Triglycerides; D002784:Cholesterol