title: Reduction in circulating bile acid and restricted diffusion across the intestinal epithelium are associated with a decrease in blood cholesterol in the presence of oat β-glucan.
abstract: Although oat (1,3:1,4)-β-glucan (BG) has been shown to decrease blood cholesterol in intervention trials, the detailed mechanism is not yet defined, but restricted reabsorption of bile acids (BAs) has been hypothesized. Using pigs as a model for humans we demonstrated that, compared to the control, BG added to the diet for 26 d caused decreases of 24% in blood total BAs (TBAs), 34% in total cholesterol (TC), and 57% in LDL cholesterol (LDL-C) (P < 0.01); decreases of 20% TBA in the midjejunum and terminal ileum (P < 0.01); increases of 80% in cecal total neutral sterols (TNSs) including cholesterol (P < 0.01); a 50% reduction in BA active transport across ex vivo ileum after 40 min (P < 0.001); and 32% decrease in jejunal microvillus heights with apparent increased goblet cell activity. The results suggest that BG not only physically hinders the active reabsorption of BAs and uptake of cholesterol, but also changes the BAs profile with lower circulating levels without excess excretion in the feces, thus resulting in reduced blood TC and LDL-C. Fermentation of sterols reaching the colon enhanced production of therapeutic ursodeoxycholic acid, suppressed toxic lithocholic acid, and decreased the possibility of cholesterol absorption by transforming the latter into coprostanol, a nonabsorbable NS.-Gunness, P., Michiels, J., Vanhaecke, L., De Smet, S., Kravchuk, O., Van de Meene, A., Gidley, M. J. Reduction in circulating bile acid and restricted diffusion across the intestinal epithelium are associated with a decrease in blood cholesterol in the presence of oat β-glucan.
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Queensland, Australia; nimagunness@uq.edu.au.
authors.forename: Purnima
authors.initials: P
authors.lastname: Gunness
authors.affiliation: Department of Applied Biosciences, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
authors.forename: Joris
authors.initials: J
authors.lastname: Michiels
authors.affiliation: Department of Animal Production, Faculty of Bioscience Engineering, Ghent University, Melle, Belgium.
authors.forename: Lynn
authors.initials: L
authors.lastname: Vanhaecke
authors.affiliation: Department of Veterinary Public Health & Food Safety, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Stefaan
authors.initials: S
authors.lastname: De Smet
authors.affiliation: Biometry Hub, School of Agriculture, Food, and Wine, The University of Adelaide, Glen Osmond, South Australia, Australia; and.
authors.forename: Olena
authors.initials: O
authors.lastname: Kravchuk
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Biosciences (Botany), The University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Allison
authors.initials: A
authors.lastname: Van de Meene
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Gidley
mesh_terms: D000818:Animals; D001647:Bile Acids and Salts / Q000097:blood*; D002784:Cholesterol / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D004043:Dietary Fiber / Q000378:metabolism; D005243:Feces / Q000166:cytology; D007413:Intestinal Mucosa / Q000378:metabolism*; D008297:Male; D013552:Swine; D014280:Triglycerides / Q000097:blood; D047071:beta-Glucans / Q000378:metabolism*
chemical_list: D001647:Bile Acids and Salts; D008078:Cholesterol, LDL; D004043:Dietary Fiber; D014280:Triglycerides; D047071:beta-Glucans; C067858:beta-glucan, (1-3)(1-4)-; D002784:Cholesterol
keywords: Ussing chamber; deoxycholic acid; microscopy; nonstarch polysaccharides; soluble dietary fiber