title: Cholesterol-Lowering Activity of Tartary Buckwheat Protein.
abstract: Previous research has shown that Tartary buckwheat flour is capable of reducing plasma cholesterol. The present study was to examine the effect of rutin and Tartary buckwheat protein on plasma total cholesterol (TC) in hypercholesterolemia hamsters. In the first animal experiment, 40 male hamsters were divided into four groups fed either the control diet or one of the three experimental diets containing 8.2 mmol rutin, 8.2 mmol quercetin, or 2.5 g kg-1cholestyramine, respectively. Results showed that only cholestyramine but not rutin and its aglycone quercetin decreased plasma TC, which suggested that rutin was not the active ingredient responsible for plasma TC-lowering activity of Tartary buckwheat flour. In the second animal experiment, 45 male hamsters were divided into five groups fed either the control diet or one of the four experimental diets containing 24% Tartary buckwheat protein, 24% rice protein, 24% wheat protein, or 5 g kg-1cholestyramine, respectively. Tartary buckwheat protein reduced plasma TC more effectively than cholestyramine (45% versus 37%), while rice and wheat proteins only reduced plasma TC by 10-13%. Tartary buckwheat protein caused 108% increase in the fecal excretion of total neutral sterols and 263% increase in the fecal excretion of total acidic sterols. real-time polymerase chain reaction and Western blotting analyses showed that Tartary buckwheat protein affected the gene expression of intestinal Niemann-Pick C1-like protein 1 (NPC1L1), acyl CoA:cholesterol acyltransferase 2 (ACAT2), and ATP binding cassette transporters 5 and 8 (ABCG5/8) in a down trend, whereas it increased the gene expression of hepatic cholesterol-7α -hydroxylase (CYP7A1). It was concluded that Tartary buckwheat protein was at least one of the active ingredients in Tartary buckwheat flour to lower plasma TC, mainly mediated by enhancing the excretion of bile acids via up-regulation of hepatic CYP7A1 and also by inhibiting the absorption of dietary cholesterol via down-regulation on intestinal NPC1L1, ACAT2 and ABCG5/8.
authors.affiliation: Food & Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors.forename: Chengnan
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Institute of Special Animal and Plant Science, China Academy of Agricultural Sciences , Changchun, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Food & Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors.forename: Yuk Man
authors.initials: YM
authors.lastname: Li
authors.affiliation: Food & Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Liang
authors.affiliation: Food & Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors.forename: Yimin
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Food & Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors.forename: Hanyue
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Food & Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors.forename: Zouyan
authors.initials: Z
authors.lastname: He
authors.forename: Jianhui
authors.initials: J
authors.lastname: Liu
authors.affiliation: Food & Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors.forename: Wangjun
authors.initials: W
authors.lastname: Hao
authors.affiliation: College of Science and Engineering, Jinan University , Guangzhou 510630, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Jiao
authors.affiliation: Food & Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors.forename: Ka Ying
authors.initials: KY
authors.lastname: Ma
authors.affiliation: Food & Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong, China.
authors.forename: Zhen-Yu
authors.identifier: http://orcid.org/0000-0001-5615-1682
authors.initials: ZY
authors.lastname: Chen
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000818:Animals; D000924:Anticholesteremic Agents / Q000378:metabolism*; D002784:Cholesterol / Q000097:blood*; D002790:Cholesterol 7-alpha-Hydroxylase / Q000235:genetics / Q000378:metabolism; D006224:Cricetinae; D019612:Fagopyrum / Q000737:chemistry*; D006801:Humans; D006937:Hypercholesterolemia / Q000178:diet therapy* / Q000235:genetics / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D008297:Male; D010936:Plant Extracts / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*
chemical_list: D018528:ATP-Binding Cassette Transporters; D000924:Anticholesteremic Agents; D010936:Plant Extracts; D010940:Plant Proteins; D002784:Cholesterol; D002790:Cholesterol 7-alpha-Hydroxylase
keywords: Tartary buckwheat protein; cholesterol; rice protein; wheat protein