The effects of dietary fiber feeding on cholesterol metabolism in rats.
The flux through the sterol biosynthetic pathway was studied in hepatocytes isolated from male Sprague-Dawley rats fed diets containing one of four fiber sources: cellulose, pectin, oat bran and wheat bran. Sterol synthesis measured by the incorporation of tritiated water or [2-14C]mevalonic acid was not inhibited in hepatocytes isolated from animals fed diets containing cellulose, pectin, oat bran or wheat bran when compared to animals fed a fiber-free diet. Based on these results, it is concluded that the intake of fiber has no inhibitory effect on endogenous sterol synthesis. In fact, in comparison to that in fiber-free controls, sterol synthesis was markedly elevated in pectin- and wheat bran-fed animals. In the case of the pectin-treated animals, the higher synthetic rate corresponded to an increase in 3-hydroxy-3-methylglutaryl coenzyme A reductase activity.
Nishina
P M
PM
School of Veterinary Medicine, University of California, Davis 95616.
Freedland
R A
RA
D000818:Animals; D001835:Body Weight; D002482:Cellulose / Q000008:administration & dosage; D002784:Cholesterol / Q000096:biosynthesis / Q000097:blood / Q000378:metabolism*; D015256:Coenzyme A-Transferases / Q000032:analysis; D004043:Dietary Fiber / Q000008:administration & dosage*; D002523:Edible Grain; D002149:Energy Intake; D006903:Hydroxymethylglutaryl CoA Reductases / Q000032:analysis; D008055:Lipids / Q000032:analysis / Q000097:blood; D008099:Liver / Q000032:analysis / Q000254:growth & development; D008297:Male; D009929:Organ Size; D010368:Pectins / Q000008:administration & dosage; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D014908:Triticum
D004043:Dietary Fiber; D008055:Lipids; D010368:Pectins; D002482:Cellulose; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases; D007862:Phosphatidylcholine-Sterol O-Acyltransferase; D015256:Coenzyme A-Transferases; C031212:acyl-CoA transferase