title: Organochlorine Pesticide-Mediated Induction of NADPH Oxidase and Nitric-Oxide Synthase in Endothelial Cell.
abstract: BACKGROUND
  Organochlorine Pesticides (OCPs) are detected ubiquitously in human and have been shown to be associated with Cardiovascular Disease (CVD) and atherosclerosis.
  
  
  OBJECTIVE
  To find out the effect of organochlorine pesticides in endothelial cell with regard to oxidative stress and associated expression of enzymes producing superoxide and Nitric Oxide (NO).
  
  
  METHODS
  Human Umbilical Vein Endothelial Cells (HUVEC) were cultured and treated with four OCPs which were found in human blood at a concentration of 0.1μM. The cells were tested for Reactive Oxygen Species (ROS) generation, NO production and mRNA expression of NAPDH oxidase (p47phox) and endothelial Nitric Oxide Synthase (eNOS). ROS generation was measured by using 2', 7'-dichlorodihydrofluorescein diacetate (H2DCFDA) method. NO was analysed by Bioxytech nitric oxide assay kit method and mRNA of NADPH oxidase and eNOS was quantified by real time PCR. Data were expressed as the mean±SEM. Comparison between the groups were made by student's t-test (2-tailed) or one-way ANOVA with Tukey's post-hoc analysis depending on number of groups. For all statistical tests, p< 0.05 was considered to be significant.
  
  
  RESULTS
  All the four pesticides generated ROS accompanied by enhanced expression of NADPH oxidase. Maximum effect was observed with β-endosulfan. Level of NO was found to be decreased significantly in endothelial cells treated with these pesticides accompanied by enhanced expression of eNOS. The antioxidant N-acetylcysteine (NAC) reduced ROS generation and enhanced NO formation. Pesticide-mediated ROS generation possibly reacts with NO forming peroxinitrite and thereby reducing the bioavailability of NO although eNOS expression is increased.
  
  
  CONCLUSIONS
  OCPs induce endothelial dysfunction through increased ROS generation via NADPH oxidase expression and reduced bioavailability of nitric oxide.
authors.affiliation: Ph. D. Scholar, Department of Biochemistry, University College of Medical Sciences , Delhi, India .
authors.forename: Rishila
authors.initials: R
authors.lastname: Ghosh
authors.affiliation: Post Doctorate Fellow, Department of Biochemistry, University College of Medical Sciences , Delhi, India .
authors.forename: Manushi
authors.initials: M
authors.lastname: Siddharth
authors.affiliation: Ph. D. Scholar, Department of Biochemistry, University College of Medical Sciences , Delhi, India .
authors.forename: Neeru
authors.initials: N
authors.lastname: Singh
authors.affiliation: Ph. D. Scholar, Department of Biochemistry, University College of Medical Sciences , Delhi, India .
authors.forename: Pawan Kumar
authors.initials: PK
authors.lastname: Kare
authors.affiliation: Professor, Department of Biochemistry, University College of Medical Sciences , Delhi, India .
authors.forename: Basu Dev
authors.initials: BD
authors.lastname: Banerjee
authors.affiliation: Professor, Department of Patholgy, University College of Medical Sciences , Delhi, India .
authors.forename: Neelam
authors.initials: N
authors.lastname: Wadhwa
authors.affiliation: Professor, Department of Biochemistry, University College of Medical Sciences , Delhi, India .
authors.forename: Ashok Kumar
authors.initials: AK
authors.lastname: Tripathi
keywords: Endothelial dysfunction; Endothelial nitric oxide synthase; N-acetylcysteine; Reactive oxygen species