title: Evidence for a role of CETP in HDL remodeling and cholesterol efflux: role of cysteine 13 of CETP.
abstract: Cholesteryl ester transfer protein (CETP), a key regulator of high-density lipoprotein (HDL) metabolism, induces HDL remodeling by transferring lipids between apolipoprotein B-containing lipoproteins and HDL, and/or by promoting lipid transfer between HDL subparticles. In this study, we investigated the mechanism as to how CETP induces the generation of lipid-poor particles (pre-β-HDL) from HDL, which increases ATP-binding cassette transporter 1-mediated cholesterol efflux. This CETP-dependent HDL remodeling is enhanced by the CETP modulator dalcetrapib both in plasma and isolated HDL. The interaction of dalcetrapib with cysteine 13 of CETP is required, since this effect was abolished when using mutant CETP in which cysteine 13 was substituted for a serine residue. Other thiol-containing compounds were identified as CETP modulators interacting with cysteine 13 of CETP. In order to mimic dalcetrapib-bound CETP, mutant CETP proteins were prepared by replacing cysteine 13 with the bulky amino acid tyrosine or tryptophan. The resultant mutants showed virtually no CETP-dependent lipid transfer activity but demonstrated preserved CETP-dependent pre-β-HDL generation. Overall, these data demonstrate that the two functions of CETP i.e., cholesteryl ester transfer and HDL remodeling can be uncoupled by interaction of thiol-containing compounds with cysteine 13 of CETP or by introducing large amino acid residues in place of cysteine 13.
authors.affiliation: F. Hoffmann-La Roche Ltd., Pharma Research & Early Development, DTA Cardiovascular and Metabolism, CH-4070, Basel, Switzerland.
authors.forename: Cyrille
authors.initials: C
authors.lastname: Maugeais
authors.affiliation: F. Hoffmann-La Roche Ltd., Pharma Research & Early Development, DTA Cardiovascular and Metabolism, CH-4070, Basel, Switzerland.
authors.forename: Anne
authors.initials: A
authors.lastname: Perez
authors.affiliation: F. Hoffmann-La Roche Ltd., Pharma Research & Early Development, DTA Cardiovascular and Metabolism, CH-4070, Basel, Switzerland.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: von der Mark
authors.affiliation: F. Hoffmann-La Roche Ltd., Pharma Research & Early Development, DTA Cardiovascular and Metabolism, CH-4070, Basel, Switzerland.
authors.forename: Christine
authors.initials: C
authors.lastname: Magg
authors.affiliation: F. Hoffmann-La Roche Ltd., Pharma Research & Early Development, DTA Cardiovascular and Metabolism, CH-4070, Basel, Switzerland.
authors.forename: Philippe
authors.initials: P
authors.lastname: Pflieger
authors.affiliation: F. Hoffmann-La Roche Ltd., Pharma Research & Early Development, DTA Cardiovascular and Metabolism, CH-4070, Basel, Switzerland. Electronic address: eric_j.niesor@roche.com.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Niesor
mesh_terms: D001692:Biological Transport / Q000235:genetics / Q000502:physiology; D002460:Cell Line; D002784:Cholesterol / Q000378:metabolism*; D053480:Cholesterol Ester Transfer Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D003545:Cysteine / Q000737:chemistry* / Q000235:genetics; D006801:Humans; D008075:Lipoproteins, HDL / Q000378:metabolism*; D010949:Plasma; D013329:Structure-Activity Relationship
chemical_list: C506642:CETP protein, human; D053480:Cholesterol Ester Transfer Proteins; D008075:Lipoproteins, HDL; D002784:Cholesterol; D003545:Cysteine
keywords: 8-(4-chlorophenylthio)-adenosine 3′,5′-cyclic monophosphate; 8-CPT-cAMP; ABCA1; ANOVA; ATP-binding cassette transporter A1; Anacetrapib; BSA; C13S-CETP, C13Y-CETP, C13R-CETP, C13W-CETP CETP; CETP; CVD; Cysteine 13; DMEM; DMSO; Dalcetrapib; Dulbecco's Modified Eagle's Medium; ELISA; FBS; HDL; HDL cholesterol; HDL-C; LDL; LDL cholesterol; LDL-C; PEG; Pre-β-HDL; RCT; Thiol; analysis of variance; apo; apolipoprotein; bovine serum albumin; cardiovascular disease; cholesteryl ester transfer protein; dimethyl sulfoxide; enzyme-linked immunosorbent assay; fetal bovine serum; high-density lipoprotein; low-density lipoprotein; polyethylene glycol; recombinant human CETP; reverse cholesterol transport; rhCETP; where cysteine residue is replaced by serine, tyrosine, arginine, or tryptophan, respectively