title: Inducible nitric oxide synthase is involved in the oxidation stress induced by HIV-1 gp120 in human retina pigment epithelial cells.
abstract: BACKGROUND
  The human immunodeficiency virus-1 (HIV-1) envelope glycoprotein gp120 has been implicated in the development of AIDS-associated retinopathy. The present study tested the hypothesis that gp120 may induce oxidative stress including up regulation of inducible nitric oxide synthase (iNOS) and production of malondialdehyde (MDA) and nitric oxide (NO) to mediate retinopathy in retinal pigment epithelial (RPE) cells.
  
  
  METHODS
  Human RPE cell line D407 was cultured and treated with gp120. HIV-1 gp120 protein induced lipid peroxidation product MDA. NO production and iNOS expression were examined in vitro by spectrophomtometry, real-time PCR, Western blotting, and confocal microscope.
  
  
  RESULTS
  Addition of gp120 was able to induce RPE cells to produce NO and MDA in time- and dose-dependent manners (P < 0.05). Similarly, gp120 was also capable of up-regulating iNOS mRNA and protein in D407 cells in time- and dose-dependent manners.
  
  
  CONCLUSIONS
  Gp120 induces oxidative stress in D407 cell by stimulating MDA and NO production, which is mediated by up-regulating iNOS expression. Gp120 may mediate oxidation stress in AIDS-associated retinopathy.
authors.affiliation: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong 510060, China.
authors.forename: Qiu-rong
authors.initials: QR
authors.lastname: Yu
authors.forename: Zhen-ping
authors.initials: ZP
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Hao-tian
authors.initials: HT
authors.lastname: Lin
authors.forename: Xiu-mei
authors.initials: XM
authors.lastname: Li
authors.forename: Ling
authors.initials: L
authors.lastname: Bai
authors.forename: Wei-bin
authors.initials: WB
authors.lastname: Cai
mesh_terms: D015153:Blotting, Western; D002460:Cell Line; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism*; D015699:HIV Envelope Protein gp120 / Q000494:pharmacology*; D006801:Humans; D007150:Immunohistochemistry; D018613:Microscopy, Confocal; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects; D016133:Polymerase Chain Reaction; D012160:Retina / Q000166:cytology*
chemical_list: D015699:HIV Envelope Protein gp120; C514793:gp120 protein, Human immunodeficiency virus 1; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II