title: Gene transfer of inducible nitric oxide synthase affords cardioprotection by upregulating heme oxygenase-1 via a nuclear factor-{kappa}B-dependent pathway.
abstract: BACKGROUND
  Although inducible nitric oxide synthase (iNOS) is known to impart powerful protection against myocardial infarction, the mechanism for this salubrious action remains unclear.
  
  
  RESULTS
  Adenovirus-mediated iNOS gene transfer in mice resulted 48 to 72 hours later in increased expression not only of iNOS protein but also of heme oxygenase (HO)-1 mRNA and protein; HO-2 protein expression did not change. iNOS gene transfer markedly reduced infarct size in wild-type mice, but this effect was completely abrogated in HO-1(-/-) mice. At 48 hours after iNOS gene transfer, nuclear factor-kappaB was markedly activated. In transgenic mice with cardiomyocyte-restricted expression of a dominant negative mutant of IkappaBalpha (IkappaBalpha(S32A,S36A)), both basal HO-1 levels and upregulation of HO-1 by iNOS gene transfer were suppressed. Chromatin immunoprecipitation analysis of mouse hearts provided direct evidence that nuclear factor-kappaB subunits p50 and p65 were recruited to the HO-1 gene promoter (-468 to -459 bp) 48 hours after iNOS gene transfer.
  
  
  CONCLUSIONS
  This study demonstrates for the first time the existence of a close functional coupling between cardiac iNOS and cardiac HO-1: iNOS upregulates HO-1 by augmenting nuclear factor-kappaB binding to the region of the HO-1 gene promoter from -468 to -459 bp, and HO-1 then mediates the cardioprotective effects of iNOS. These results also reveal an important role of nuclear factor-kappaB in both basal and iNOS-induced expression of cardiac HO-1. Collectively, the present findings significantly expand our understanding of the regulation of cardiac HO-1 and of the mechanism whereby iNOS exerts its cardioprotective actions.
authors.affiliation: Division of Cardiology, University of Louisville, Louisville, KY 40292, USA.
authors.forename: Qianhong
authors.initials: Q
authors.lastname: Li
authors.forename: Yiru
authors.initials: Y
authors.lastname: Guo
authors.forename: Qinghui
authors.initials: Q
authors.lastname: Ou
authors.forename: Chuanjue
authors.initials: C
authors.lastname: Cui
authors.forename: Wen-Jian
authors.initials: WJ
authors.lastname: Wu
authors.forename: Wei
authors.initials: W
authors.lastname: Tan
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Zhu
authors.forename: Lilibeth B
authors.initials: LB
authors.lastname: Lanceta
authors.forename: Santosh K
authors.initials: SK
authors.lastname: Sanganalmath
authors.forename: Buddhadeb
authors.initials: B
authors.lastname: Dawn
authors.forename: Ken
authors.initials: K
authors.lastname: Shinmura
authors.forename: Gregg D
authors.initials: GD
authors.lastname: Rokosh
authors.forename: Shuyan
authors.initials: S
authors.lastname: Wang
authors.forename: Roberto
authors.initials: R
authors.lastname: Bolli
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D001663:Bilirubin / Q000378:metabolism; D001831:Body Temperature; D005260:Female; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D006321:Heart / Q000502:physiology*; D006339:Heart Rate; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism*; D020672:I-kappa B Proteins / Q000235:genetics; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009203:Myocardial Infarction / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D015854:Up-Regulation / Q000502:physiology
chemical_list: D020672:I-kappa B Proteins; D016328:NF-kappa B; C000606205:Nfkbia protein, mouse; D012333:RNA, Messenger; D000072000:NF-KappaB Inhibitor alpha; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; D051547:Heme Oxygenase-1; D001663:Bilirubin