title: Cooked rice prevents hyperlipidemia in hamsters fed a high-fat/cholesterol diet by the regulation of the expression of hepatic genes involved in lipid metabolism.
abstract: Rice has many health-beneficial components for ameliorating obesity, diabetes, and dyslipidemia. However, the effect of cooked rice as a useful carbohydrate source has not been investigated yet; so we hypothesized that cooked rice may have hypolipidemic effects. In the present study, we investigated the effect of cooked rice on hyperlipidemia and on the expression of hepatic genes involved in lipid metabolism. Golden Syrian hamsters were divided into 2 groups and fed a high-fat (15%, wt/wt)/cholesterol (0.5%, wt/wt) diet supplemented with either corn starch (HFD, 54.5% wt/wt) or cooked rice (HFD-CR, 54.5% wt/wt) as the main carbohydrate source for 8 weeks. In the HFD-CR group, the triglyceride and total cholesterol levels in the serum and liver were decreased, and the total lipid, total cholesterol, and bile acid levels in the feces were increased, compared with the HFD group. In the cooked-rice group, the messenger RNA and protein levels of 3-hydroxy-3-methylglutaryl CoA reductase were significantly downregulated; and the messenger RNA and protein levels of the low-density lipoprotein receptor and cholesterol-7α-hydroxylase were upregulated. Furthermore, the expressions of lipogenic genes such as sterol response element binding protein-1, fatty acid synthase, acetyl CoA carboxylase, and stearoyl CoA desaturase-1 were downregulated, whereas the β-oxidation related genes (carnitine palmitoyl transferase-1, acyl CoA oxidase, and peroxisome proliferator-activated receptor α) were upregulated, in the cooked-rice group. Our results suggest that the hypolipidemic effect of cooked rice is partially mediated by the regulation of hepatic genes involved in lipid metabolism, which results in the suppression of cholesterol and fatty acid synthesis and the enhancement of cholesterol excretion and fatty acid β-oxidation.
authors.affiliation: Division of Metabolism and Functionality Research, Korea Food Research Institute, 516, Baekhyun-Dong, Bundang-Gu, Sungnam 463-746, Republic of Korea.
authors.forename: Won Hee
authors.initials: WH
authors.lastname: Choi
authors.forename: So Young
authors.initials: SY
authors.lastname: Gwon
authors.forename: Jiyun
authors.initials: J
authors.lastname: Ahn
authors.forename: Chang Hwa
authors.initials: CH
authors.lastname: Jung
authors.forename: Tae Youl
authors.initials: TY
authors.lastname: Ha
mesh_terms: D000818:Animals; D002791:Cholesterol, Dietary / Q000009:adverse effects* / Q000378:metabolism; D003296:Cooking; D006224:Cricetinae; D059305:Diet, High-Fat / Q000009:adverse effects*; D004040:Dietary Carbohydrates / Q000494:pharmacology / Q000627:therapeutic use*; D005786:Gene Expression Regulation / Q000187:drug effects; D006949:Hyperlipidemias / Q000209:etiology / Q000235:genetics / Q000378:metabolism / Q000517:prevention & control*; D000960:Hypolipidemic Agents / Q000494:pharmacology / Q000627:therapeutic use; D050356:Lipid Metabolism / Q000235:genetics*; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008647:Mesocricetus; D012275:Oryza; D028321:Plant Preparations / Q000494:pharmacology / Q000627:therapeutic use; D012333:RNA, Messenger / Q000378:metabolism; D012639:Seeds
chemical_list: D002791:Cholesterol, Dietary; D004040:Dietary Carbohydrates; D000960:Hypolipidemic Agents; D028321:Plant Preparations; D012333:RNA, Messenger
keywords: 3-hydroxy-3-methylglutaryl CoA reductase; ACC1; ACOX; CPT-1; CYP7A1; Cooked rice; FAS; HFD; HFD-CR; HMG-CoAR; Hamster; Hyperlipidemia; LDLR; Lipogenic; PPARα; SCD-1; SREBP-1c; acetyl CoA carboxylase; acyl CoA oxidase; carnitine palmitoyl transferase-1; cholesterol-7α-hydroxylase; fatty acid synthase; high fat diet supplemented with cooked rice; high-fat diet; low-density lipoprotein receptor; peroxisome proliferator-activated receptor α; stearoyl CoA desaturase-1; sterol response element binding protein-1; β-Oxidation