title: Nox2 contributes to cardiac fibrosis in diabetic cardiomyopathy in a transforming growth factor-β dependent manner.
abstract: OBJECTIVE
  This study aimed to investigate the effect of Nox2 on cardiac fibrosis and to elucidate the regulatory mechanism of Nox2 in the development of DCM.
  
  
  METHODS
  We established normal and insulin-resistant cellular model using neonatal rat cardiac fibroblasts. Then Nox2-specific siRNA were transfected into cardiac fibroblasts with Lipofectamine ® 2000 and crambled siRNA sequence was considered as control. Meanwhile, a part of cells were randomly selected to be treated with or without transforming growth factor-β (TGF-β). Moreover, quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were respectively performed to determine the expression level of related molecules, such as Nox2, collagen type I and III (COL I and III) and PI3K/AKT and PKC/Rho signaling pathway-related proteins.
  
  
  RESULTS
  TGF-β stimulation significantly increased the expression level of Nox2 both in mRNA and protein levels. Suppression of the Nox2 markedly decreased the expression of COL I and COL III in normal and insulin-resistant cellular model with TGF-β stimulation. Moreover, suppression of the Nox2 significantly decreased the expression of PI3K/AKT and PKC/Rho signaling pathway-related proteins in insulin-resistant cellular model with TGF-β stimulation. However, suppression of Nox2 had no effects on these proteins without TGF-β stimulation.
  
  
  CONCLUSIONS
  Our finding reveals that Nox2 may promote synthesis of COL I and III via involved in PI3K/AKT and PKC/Rho signaling pathway in a TGF-β dependent manner and consequently promote cardiac fibrosis in the development of DCM.
authors.affiliation: Department of Health Care, The Forth People's Hospital of Jinan City Jinan 250031, China.
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Endocrinology, Binzhou City Central Hospital Binzhou 251700, China.
authors.forename: Jinhua
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003094:Collagen / Q000096:biosynthesis; D058065:Diabetic Cardiomyopathies / Q000378:metabolism / Q000473:pathology*; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000378:metabolism; D005355:Fibrosis / Q000378:metabolism / Q000473:pathology; D008562:Membrane Glycoproteins / Q000378:metabolism*; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000378:metabolism*; D034741:RNA, Small Interfering; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D014162:Transfection; D016212:Transforming Growth Factor beta / Q000378:metabolism*
chemical_list: D008562:Membrane Glycoproteins; D034741:RNA, Small Interfering; D016212:Transforming Growth Factor beta; D003094:Collagen; C500593:Cybb protein, rat; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases
keywords: Diabetic cardiomyopathy; Nox 2; cardiac fibrosis; transforming growth factor-β