title: Molecular mechanisms of (-)-epicatechin and chlorogenic acid on the regulation of the apoptotic and survival/proliferation pathways in a human hepatoma cell line.
abstract: Dietary polyphenols have been associated with reduced risk of chronic diseases, but the precise molecular mechanisms of protection remain unclear. This work was aimed at studying the effect of (-)-epicatechin (EC) and chlorogenic acid (CGA) on the regulation of apoptotic and survival/proliferation pathways in a human hepatoma cell line (HepG2). EC or CGA treatment for 18 h had a slight effect on cell viability and decreased reactive oxygen species formation, and EC alone promoted cell proliferation, whereas CGA increased glutathione levels. Phenols neither induced the caspase cascade for apoptosis nor affected expression levels of Bcl-xL or Bax. A sustained activation of the major survival signals AKT/PI-3-kinase and ERK was shown in EC-treated cells, rather than in CGA-exposed cells. These data suggest that EC and CGA have no effect on apoptosis and enhance the intrinsic cellular tolerance against oxidative insults either by activating survival/proliferation pathways or by increasing antioxidant potential in HepG2.
authors.affiliation: Department of Metabolism and Nutrition, Instituto del Frío, Consejo Superior de Investigaciones Científicas, José Antonio Novais 10, Ciudad Universitaria, 28040 Madrid, Spain.
authors.forename: Ana Belén
authors.initials: AB
authors.lastname: Granado-Serrano
authors.forename: María Angeles
authors.initials: MA
authors.lastname: Martín
authors.forename: María
authors.initials: M
authors.lastname: Izquierdo-Pulido
authors.forename: Luis
authors.initials: L
authors.lastname: Goya
authors.forename: Laura
authors.initials: L
authors.lastname: Bravo
authors.forename: Sonia
authors.initials: S
authors.lastname: Ramos
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular; D002392:Catechin / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects*; D002726:Chlorogenic Acid / Q000494:pharmacology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D002726:Chlorogenic Acid; D002392:Catechin; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases