title: Subchronic treatment with grape-seed phenolics inhibits ghrelin production despite a short-term stimulation of ghrelin secretion produced by bitter-sensing flavanols.
abstract: Grape-seed phenolic compounds have recently been described as satiating agents in rats when administered as a whole phenolic extract (GSPE). This satiating effect may involve the release of satiating gut hormones such as GLP-1, although a short-term increase in the orexigenic hormone ghrelin was also reported. In this study, we investigated the short- and long-term effects of GSPE in rats, focusing on the role of the main grape-seed phenolics in ghrelin secretion.
  
  
  
  GSPE produced a short-term increase in plasma ghrelin in rats after an acute treatment. A mouse ghrelinoma cell line was used to test the effects of the main pure grape-seed phenolic compounds on ghrelin release. Monomeric flavanols stimulated ghrelin secretion by activating bitter taste receptors. In contrast, gallic acid (GA) and oligomeric flavanols inhibited ghrelin release. The ghrelin-inhibiting effects of GA were confirmed in rats and in rat duodenal segments. One day after the last dose of a subchronic treatment, GSPE decreased plasma ghrelin in rats, ghrelin secretion in intestinal segments, and ghrelin mRNA expression in stomach.
  
  
  
  The sustained satiating effects of GSPE are related to a long-term decrease in ghrelin expression. GA and oligomeric flavanols play a ghrelin-inhibiting role in this process.
authors.affiliation: MoBioFood Research Group, Departament de Bioquímica i Biotecnologia, Universitat Rovira i Virgili, Tarragona, Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: Serrano
authors.affiliation: MoBioFood Research Group, Departament de Bioquímica i Biotecnologia, Universitat Rovira i Virgili, Tarragona, Spain.
authors.forename: Àngela
authors.initials: À
authors.lastname: Casanova-Martí
authors.affiliation: Gut Peptide Research Lab, Translational Research Center for Gastrointestinal Disorders, KU Leuven, Leuven, Belgium.
authors.forename: Inge
authors.initials: I
authors.lastname: Depoortere
authors.affiliation: MoBioFood Research Group, Departament de Bioquímica i Biotecnologia, Universitat Rovira i Virgili, Tarragona, Spain.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Blay
authors.affiliation: MoBioFood Research Group, Departament de Bioquímica i Biotecnologia, Universitat Rovira i Virgili, Tarragona, Spain.
authors.forename: Ximena
authors.initials: X
authors.lastname: Terra
authors.affiliation: MoBioFood Research Group, Departament de Bioquímica i Biotecnologia, Universitat Rovira i Virgili, Tarragona, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Pinent
authors.affiliation: MoBioFood Research Group, Departament de Bioquímica i Biotecnologia, Universitat Rovira i Virgili, Tarragona, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Ardévol
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D005260:Female; D005707:Gallic Acid; D005753:Gastric Mucosa / Q000378:metabolism; D005786:Gene Expression Regulation; D054439:Ghrelin / Q000097:blood* / Q000378:metabolism; D056604:Grape Seed Extract / Q000494:pharmacology*; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000187:drug effects*; D008297:Male; D051379:Mice; D059808:Polyphenols / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D013270:Stomach / Q000187:drug effects*; D013274:Stomach Neoplasms / Q000188:drug therapy; D027843:Vitis / Q000737:chemistry
chemical_list: D000975:Antioxidants; D054439:Ghrelin; D056604:Grape Seed Extract; D059808:Polyphenols; D012333:RNA, Messenger; D005707:Gallic Acid
keywords: Bitter agonists; Flavanols; Food intake; Gallic acid; Ghrelin