title: Role of SIRT1 and FOXO factors in eNOS transcriptional activation by resveratrol.
abstract: Many of the cardiovascular protective effects of resveratrol are attributable to an enhanced production of nitric oxide (NO) by the endothelial NO synthase (eNOS). Resveratrol has been shown to enhance eNOS gene expression as well as eNOS enzymatic activity. The aim of the present study was to analyze the molecular mechanisms of eNOS transcriptional activation by resveratrol. Treatment of human EA.hy 926 endothelial cells with resveratrol led to a concentration-dependent upregulation of eNOS expression. In luciferase reporter gene assay, resveratrol enhanced the activity of human eNOS promoter fragments (3500, 1600, 633 and 263bp in length, respectively), indicating that the proximal promoter region is required for resveratrol-induced eNOS transcriptional activation. Knockdown of the NAD(+)-dependent protein deacetylase sirtuin 1 (SIRT1) by siRNA prevented the upregulation of eNOS mRNA and protein by resveratrol. Forkhead box O (FOXO) transcription factors are established downstream targets of SIRT1. siRNA-mediated knockdown of FOXO1 and FOXO3a abolished the effect of resveratrol on eNOS expression, indicating the involvement of these factors. Resveratrol treatment enhanced the expression of FOXO1 and FOXO3a in EA.hy 926 cells. Reporter gene assay using promoter containing forkhead response elements showed increased FOXO factor activity by resveratrol. In electrophoretic mobility shift assay, the enhanced binding of nuclear proteins to the eNOS promoter regions by resveratrol could be blocked by antibodies against FOXO1 and FOXO3a. In conclusion, resveratrol enhances the expression and activity of FOXO transcription factors. The SIRT1/FOXO factor axis is involved in resveratrol-induced eNOS transcriptional activation.
authors.affiliation: Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany.
authors.forename: Ning
authors.initials: N
authors.lastname: Xia
authors.forename: Susanne
authors.initials: S
authors.lastname: Strand
authors.forename: Frank
authors.initials: F
authors.lastname: Schlufter
authors.forename: Daniel
authors.initials: D
authors.lastname: Siuda
authors.forename: Gisela
authors.initials: G
authors.lastname: Reifenberg
authors.forename: Hartmut
authors.initials: H
authors.lastname: Kleinert
authors.forename: Ulrich
authors.initials: U
authors.lastname: Förstermann
authors.forename: Huige
authors.initials: H
authors.lastname: Li
mesh_terms: D000704:Analysis of Variance; D002460:Cell Line; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D006801:Humans; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D034741:RNA, Small Interfering / Q000235:genetics; D000077185:Resveratrol; D056564:Sirtuin 1 / Q000235:genetics / Q000378:metabolism*; D013267:Stilbenes / Q000494:pharmacology*; D015533:Transcriptional Activation / Q000187:drug effects*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D051858:Forkhead Transcription Factors; D034741:RNA, Small Interfering; D013267:Stilbenes; C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III; C447939:SIRT1 protein, human; D056564:Sirtuin 1; D000077185:Resveratrol