title: Cocoa flavanol metabolites activate HNF-3β, Sp1, and NFY-mediated transcription of apolipoprotein AI in human cells.
abstract: METHODS
  To identify the mechanisms by which cocoa induces HDL levels and since apolipoprotein AI (ApoAI) is the major protein in HDLs, we analyzed, upon incubation with cocoa metabolites, ApoAI mRNA levels, its transcriptional regulation, and the levels of the transcription factors involved in this process.
  
  
  RESULTS
  Epicatechin and cocoa metabolites caused an increase in ApoAI expression in HepG2 cells. Electrophoretic mobility shift assays revealed the involvement of Sites A and B of the ApoAI promoter in the induction of ApoAI mRNA upon incubation with cocoa metabolites. Using supershift assays, we demonstrated the binding of HNF-3β, HNF-4, ER-α, and RXR-α to Site A and the binding of HNF-3β, NFY, and Sp1 to Site B. Luciferase assays performed with a construct containing Site B confirmed its role in the upregulation of ApoAI by cocoa metabolites. Incubation with 3-methyl-epicatechin led to an increase in HNF-3β mRNA, HNF-3β, ER-α, Sp1, and NFY protein levels and the activation of ApoAI transcription mediated by NFY, Sp1, and ER-α.
  
  
  CONCLUSIONS
  The activation of ApoAI transcription through Site B by cocoa flavanol metabolites is mainly mediated by an increase in HNF-3β, with a significant contribution of Sp1 and NFY, as a mechanism for the protective role of these compounds in cardiovascular diseases.
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Barcelona, Barcelona, Spain.
authors.forename: Carlota
authors.initials: C
authors.lastname: Oleaga
authors.forename: Carlos J
authors.initials: CJ
authors.lastname: Ciudad
authors.forename: Maria
authors.initials: M
authors.lastname: Izquierdo-Pulido
authors.forename: Véronique
authors.initials: V
authors.lastname: Noé
mesh_terms: D016632:Apolipoprotein A-I / Q000235:genetics* / Q000378:metabolism; D000069059:Atorvastatin; D001665:Binding Sites; D023081:CCAAT-Binding Factor / Q000378:metabolism*; D002099:Cacao / Q000737:chemistry* / Q000378:metabolism; D002392:Catechin / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology*; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism; D005419:Flavonoids / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D056945:Hep G2 Cells / Q000187:drug effects; D051542:Hepatocyte Nuclear Factor 3-beta / Q000235:genetics / Q000378:metabolism*; D051557:Hepatocyte Nuclear Factor 4 / Q000378:metabolism; D006538:Heptanoic Acids / Q000494:pharmacology; D006801:Humans; D011401:Promoter Regions, Genetic; D011758:Pyrroles / Q000494:pharmacology; D016329:Sp1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D015854:Up-Regulation / Q000187:drug effects
chemical_list: C424450:3'-O-methylepicatechin; D016632:Apolipoprotein A-I; D023081:CCAAT-Binding Factor; C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D005419:Flavonoids; C496592:HNF4A protein, human; D051557:Hepatocyte Nuclear Factor 4; D006538:Heptanoic Acids; D011758:Pyrroles; D016329:Sp1 Transcription Factor; C402244:nuclear factor Y; D051542:Hepatocyte Nuclear Factor 3-beta; D002392:Catechin; D000069059:Atorvastatin