title: Fibrates and fish oil, but not corn oil, up-regulate the expression of the cholesteryl ester transfer protein (CETP) gene.
abstract: Cholesteryl ester transfer protein (CETP) is a plasma protein that reduces high density lipoprotein (HDL)-cholesterol (chol) levels and may increase atherosclerosis risk. n-3 and n-6 polyunsaturated fatty acids (PUFAs) are natural ligands, and fibrates are synthetic ligands for peroxisome proliferator activated receptor-alpha (PPARα), a transcription factor that modulates lipid metabolism. In this study, we investigated the effects of PUFA oils and fibrates on CETP expression. Hypertriglyceridemic CETP transgenic mice were treated with gemfibrozil, fenofibrate, bezafibrate or vehicle (control), and normolipidemic CETP transgenic mice were treated with fenofibrate or with fish oil (FO; n-3 PUFA rich), corn oil (CO, n-6 PUFA rich) or saline. Compared with the control treatment, only fenofibrate significantly diminished triglyceridemia (50%), whereas all fibrates decreased the HDL-chol level. Elevation of the CETP liver mRNA levels and plasma activity was observed in the fenofibrate (53%) and gemfibrozil (75%) groups. Compared with saline, FO reduced the plasma levels of nonesterified fatty acid (26%), total chol (15%) and HDL-chol (20%). Neither of the oil treatments affected the plasma triglyceride levels. Compared with saline, FO increased the plasma adiponectin level and reduced plasma leptin levels, whereas CO increased the leptin levels. FO, but not CO, significantly increased the plasma CETP mass (90%) and activity (23%) as well as increased the liver level of CETP mRNA (28%). In conclusion, fibrates and FO, but not CO, up-regulated CETP expression at both the mRNA and protein levels. We propose that these effects are mediated by the activation of PPARα, which acts on a putative PPAR response element in the CETP gene.
authors.affiliation: Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, SP, Brazil.
authors.forename: Helena F
authors.initials: HF
authors.lastname: Raposo
authors.affiliation: Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, SP, Brazil.
authors.forename: Patrícia R
authors.initials: PR
authors.lastname: Patrício
authors.affiliation: Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, SP, Brazil.
authors.forename: Mariana C
authors.initials: MC
authors.lastname: Simões
authors.affiliation: Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, SP, Brazil. Electronic address: ho98@unicamp.br.
authors.forename: Helena C F
authors.initials: HC
authors.lastname: Oliveira
mesh_terms: D000818:Animals; D001629:Bezafibrate / Q000627:therapeutic use; D053480:Cholesterol Ester Transfer Proteins / Q000819:agonists* / Q000097:blood / Q000235:genetics / Q000378:metabolism; D003131:Combined Modality Therapy; D003314:Corn Oil / Q000627:therapeutic use; D003433:Crosses, Genetic; D019587:Dietary Supplements; D005260:Female; D011345:Fenofibrate / Q000627:therapeutic use; D058607:Fibric Acids / Q000627:therapeutic use*; D005395:Fish Oils / Q000627:therapeutic use*; D015248:Gemfibrozil / Q000627:therapeutic use; D015228:Hypertriglyceridemia / Q000097:blood / Q000188:drug therapy* / Q000378:metabolism / Q000517:prevention & control; D000960:Hypolipidemic Agents / Q000627:therapeutic use*; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008822:Mice, Transgenic; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D015854:Up-Regulation / Q000187:drug effects*
chemical_list: C506642:CETP protein, human; D053480:Cholesterol Ester Transfer Proteins; D058607:Fibric Acids; D005395:Fish Oils; D000960:Hypolipidemic Agents; D012333:RNA, Messenger; D003314:Corn Oil; D015248:Gemfibrozil; D011345:Fenofibrate; D001629:Bezafibrate
keywords: CETP expression; Fibrates; Fish oil; Omega-3 polyunsaturated fatty acids