title: Inhibition of activator protein-1, NF-kappaB, and MAPKs and induction of phase 2 detoxifying enzyme activity by chlorogenic acid.
abstract: Chlorogenic acid, the ester of caffeic acid with quinic acid, is one of the most abundant polyphenols in the human diet. The antioxidant and anticarcinogenic properties of chlorogenic acid have been established in animal studies. However, little is known about the molecular mechanisms through which chlorogenic acid inhibits carcinogenesis. In this study, we found that chlorogenic acid inhibited the proliferation of A549 human cancer cells in vitro. The results of the soft agar assay indicated that chlorogenic acid suppressed 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced neoplastic transformation of JB6 P+ cells in a dose-dependent manner. Pretreatment of JB6 cells with chlorogenic acid blocked UVB- or TPA-induced transactivation of AP-1 and NF-kappaB over the same dose range. At low concentrations, chlorogenic acid decreased the phosphorylation of c-Jun NH2-terminal kinases, p38 kinase, and MAPK kinase 4 induced by UVB/12-O-tetradecanoylphorbol-13-acetate, yet higher doses were required to inhibit extracellular signal-regulated kinases. Chlorogenic acid also increased the enzymatic activities of glutathione S-transferases (GST) and NAD(P)H: quinone oxidoreductase. Further studies indicated that chlorogenic acid could stimulate the nuclear translocation of Nrf2 (NF-E2-related factor) as well as subsequent induction of GSTA1 antioxidant response element (ARE)-mediated GST activity. The phosphatidylinositol 3-kinase pathway might be involved in the activation of Nrf2 translocation. These results provide the first evidence that chlorogenic acid could protect against environmental carcinogen-induced carcinogenesis and suggest that the chemopreventive effects of chlorogenic acid may be through its up-regulation of cellular antioxidant enzymes and suppression of ROS-mediated NF-kappaB, AP-1, and MAPK activation.
authors.affiliation: Pathology and Physiology Research Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, USA.
authors.forename: Rentian
authors.initials: R
authors.lastname: Feng
authors.forename: Yongju
authors.initials: Y
authors.lastname: Lu
authors.forename: Linda L
authors.initials: LL
authors.lastname: Bowman
authors.forename: Yong
authors.initials: Y
authors.lastname: Qian
authors.forename: Vincent
authors.initials: V
authors.lastname: Castranova
authors.forename: Min
authors.initials: M
authors.lastname: Ding
mesh_terms: D000362:Agar / Q000494:pharmacology; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic; D002726:Chlorogenic Acid / Q000378:metabolism* / Q000494:pharmacology; D003600:Cytosol / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D017097:Electric Impedance; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D017930:Genes, Reporter; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism; D008156:Luciferases / Q000378:metabolism; D020935:MAP Kinase Signaling System; D051379:Mice; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D051267:NF-E2-Related Factor 2; D016328:NF-kappa B / Q000037:antagonists & inhibitors*; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D021381:Protein Transport; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D015534:Trans-Activators / Q000378:metabolism*; D018808:Transcription Factor AP-1 / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D015533:Transcriptional Activation; D014466:Ultraviolet Rays; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D000975:Antioxidants; D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors; D007527:Isoenzymes; D051267:NF-E2-Related Factor 2; D016328:NF-kappa B; C495635:NFE2L2 protein, human; C495636:Nfe2l2 protein, mouse; D015534:Trans-Activators; D018808:Transcription Factor AP-1; D002726:Chlorogenic Acid; D000362:Agar; D008156:Luciferases; D009247:NADH, NADPH Oxidoreductases; D005982:Glutathione Transferase; C119995:glutathione S-transferase alpha; D048049:Extracellular Signal-Regulated MAP Kinases; C102548:Mapk4 protein, rat; D048051:p38 Mitogen-Activated Protein Kinases; D013755:Tetradecanoylphorbol Acetate