title: Redox-sensitive up-regulation of eNOS by purple grape juice in endothelial cells: role of PI3-kinase/Akt, p38 MAPK, JNK, FoxO1 and FoxO3a.
abstract: The vascular protective effect of grape-derived polyphenols has been attributable, in part, to their direct action on blood vessels by stimulating the endothelial formation of nitric oxide (NO). The aim of the present study was to determine whether Concord grape juice (CGJ), which contains high levels of polyphenols, stimulates the expression of endothelial NO synthase (eNOS) in porcine coronary artery endothelial cells and, if so, to determine the signaling pathway involved. CGJ dose- and time-dependently increased eNOS mRNA and protein levels and this effect is associated with an increased formation of NO in endothelial cells. The stimulatory effect of CGJ on eNOS mRNA is not associated with an increased eNOS mRNA stability and inhibited by antioxidants such as MnTMPyP, PEG-catalase, and catalase, and by wortmannin (an inhibitor of PI3-kinase), SB 203580 (an inhibitor of p38 MAPK), and SP 600125 (an inhibitor of JNK). Moreover, CGJ induced the formation of reactive oxygen species (ROS) in endothelial cells and this effect is inhibited by MnTMPyP, PEG-catalase, and catalase. The CGJ-induced the phosphorylation of p38 MAPK and JNK kinases is abolished by MnTMPyP. CGJ induced phosphorylation of transcription factors FoxO1 and FoxO3a, which regulate negatively eNOS expression, and this effect is prevented by MnTMPyP, PEG-catalase, wortmannin, SB203580 and SP600125. Moreover, chromatin immunoprecipitation assay indicated that the FoxO3a protein is associated with the eNOS promoter in control cells and that CGJ induced its dissociation. Thus, the present study indicates that CGJ up-regulates the expression of eNOS mRNA and protein leading to an increased formation of NO in endothelial cells. The stimulatory effect of CGJ is a redox-sensitive event involving PI3-kinase/Akt, p38 MAPK and JNK pathways, and the inactivation of the FoxO transcription factors, FoxO1 and FoxO3a, thereby preventing their repression of the eNOS gene.
authors.affiliation: CNRS UMR 7213 Laboratoire de Biophotonique et Pharmacologie, Université de Strasbourg, Faculté de Pharmacie, Illkirch, France.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Alhosin
authors.forename: Eric
authors.initials: E
authors.lastname: Anselm
authors.forename: Sherzad
authors.initials: S
authors.lastname: Rashid
authors.forename: Jong Hun
authors.initials: JH
authors.lastname: Kim
authors.forename: Socorro Vanesca Frota
authors.initials: SV
authors.lastname: Madeira
authors.forename: Christian
authors.initials: C
authors.lastname: Bronner
authors.forename: Valérie B
authors.initials: VB
authors.lastname: Schini-Kerth
mesh_terms: D000818:Animals; D000873:Anthracenes / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D001628:Beverages; D015153:Blotting, Western; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D003331:Coronary Vessels / Q000166:cytology*; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism*; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D007093:Imidazoles / Q000494:pharmacology; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008665:Metalloporphyrins / Q000494:pharmacology; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism*; D009589:Nitrogen Oxides / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D058539:Phosphatidylinositol 3-Kinase / Q000378:metabolism*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology; D012333:RNA, Messenger; D017382:Reactive Oxygen Species / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D013552:Swine; D027843:Vitis / Q000737:chemistry*; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D000873:Anthracenes; D000975:Antioxidants; D051858:Forkhead Transcription Factors; D007093:Imidazoles; D008665:Metalloporphyrins; C502230:Mn(III) 5,10,15,20-tetrakis(N-methylpyridinium-2-yl)porphyrin; D009589:Nitrogen Oxides; D000081082:Phosphoinositide-3 Kinase Inhibitors; D011725:Pyridines; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; C432165:pyrazolanthrone; D052250:Nitric Oxide Synthase Type III; D058539:Phosphatidylinositol 3-Kinase; D048031:JNK Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C093642:SB 203580