title: Lack of evidence for a liver or intestinal miRNA regulation involved in the hypertriglyceridemic effect of APOC3 3'UTR variant SstI.
abstract: APOC3 is a major regulator of triglycerides metabolism. Several APOC3 variants are associated with hypertriglyceridemia (HTG). Our aim was to establish the potential regulation of APOC3 3'UTR variants associated with HTG by liver or intestinal miRNAs.
  
  
  
  We sequenced APOC3 3'UTR in 100 type 2 diabetic (TD2) patients with severe HTG (TG > 15 mmol/L) (HTG group) compared to 100 normotriglyceridemic patients (NTG group). We performed in silico studies to identify potential loss of miRNA binding induced by APOC3 3'UTR variants. We also performed in vitro studies to test the functionality of miRNA/APOC3 variants interactions: APOC3 3'UTR plasmids coupled with a firefly luciferase reporter were transfected in HepG2, HuH-7 and Caco-2 cells.
  
  
  
  We identified only two variants: SstI (rs5128) and BbvI (rs5225) in APOC3 3'UTR in the 2 groups of patients. Only the SstI-S2 rare allele was significantly associated with HTG (allele frequency 19,5% in HTG group vs. 9,5% in NTG group, p = 0.0045). In silico studies predicted a potential loss in the binding of 5 miRNAs induced by the S2 variant. These 5 miRNAs are all endogenously expressed in human liver and intestine, as well as in the cell models studied. However, in vitro, the S2 variant did not modulate APOC3 3'UTR reporter gene expression in HepG2, HuH-7 and Caco-2 cells.
  
  
  
  Our results do not confirm the hypothesis of a direct regulation of the APOC3 SstI variant by hepatic or intestinal miRNAs.
authors: INSERM U1060, Laboratoire Carmen, Université Lyon 1, INRA U1235, INSA de Lyon, CENS, Centre de Recherche en Nutrition Humaine Rhône-Alpes, Villeurbanne F-69621, Oullins Cedex F-69921, France; Hospices Civils de Lyon, Centre Hospitalier Lyon-Sud, Centre de Biologie Sud, Laboratoire de Biochimie moléculaire et métabolique, Pierre-Bénite Cedex F-69495, France.
authors: Marine
authors: M
authors: Dancer
authors: INSERM U1060, Laboratoire Carmen, Université Lyon 1, INRA U1235, INSA de Lyon, CENS, Centre de Recherche en Nutrition Humaine Rhône-Alpes, Villeurbanne F-69621, Oullins Cedex F-69921, France; Hospices Civils de Lyon, Centre hospitalier Lyon Sud, Service d'endocrinologie, Pierre-Bénite Cedex F-69495, France.
authors: Cyrielle
authors: C
authors: Caussy
authors: INSERM U1060, Laboratoire Carmen, Université Lyon 1, INRA U1235, INSA de Lyon, CENS, Centre de Recherche en Nutrition Humaine Rhône-Alpes, Villeurbanne F-69621, Oullins Cedex F-69921, France; Hospices Civils de Lyon, Centre de Biologie et de Pathologie Est, Département de biochimie et biologie moléculaire, Bron Cedex F-69677, France.
authors: Mathilde
authors: M
authors: Di Filippo
authors: INSERM U1060, Laboratoire Carmen, Université Lyon 1, INRA U1235, INSA de Lyon, CENS, Centre de Recherche en Nutrition Humaine Rhône-Alpes, Villeurbanne F-69621, Oullins Cedex F-69921, France; Hospices Civils de Lyon, Hôpital Louis Pradel, Fédération d'endocrinologie, Bron Cedex F-69677, France.
authors: Philippe
authors: P
authors: Moulin
authors: INSERM U1060, Laboratoire Carmen, Université Lyon 1, INRA U1235, INSA de Lyon, CENS, Centre de Recherche en Nutrition Humaine Rhône-Alpes, Villeurbanne F-69621, Oullins Cedex F-69921, France; Hospices Civils de Lyon, Centre Hospitalier Lyon-Sud, Centre de Biologie Sud, Laboratoire de Biochimie moléculaire et métabolique, Pierre-Bénite Cedex F-69495, France.
authors: Christophe
authors: C
authors: Marçais
authors: INSERM U1060, Laboratoire Carmen, Université Lyon 1, INRA U1235, INSA de Lyon, CENS, Centre de Recherche en Nutrition Humaine Rhône-Alpes, Villeurbanne F-69621, Oullins Cedex F-69921, France; Hospices Civils de Lyon, Hôpital Louis Pradel, Fédération d'endocrinologie, Bron Cedex F-69677, France. Electronic address: sybil.charriere@chu-lyon.fr.
authors: Sybil
authors: S
authors: Charrière
mesh_terms: D020413:3' Untranslated Regions; D053305:Apolipoprotein C-III / Q000235:genetics*; D001665:Binding Sites; D018938:Caco-2 Cells; D016022:Case-Control Studies; D019295:Computational Biology; D003198:Computer Simulation; D030541:Databases, Genetic; D005786:Gene Expression Regulation; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D056945:Hep G2 Cells; D006801:Humans; D015228:Hypertriglyceridemia / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D012720:Severity of Illness Index; D014162:Transfection
chemical_list: D020413:3' Untranslated Regions; D053305:Apolipoprotein C-III; D035683:MicroRNAs
keywords: APOC3; Lipids; Polymorphism; SNP; Triglycerides; miR; microRNA