title: In vitro Staphylococcus aureus-induced oxidative stress in mice murine peritoneal macrophages: a duration-dependent approach.
abstract: OBJECTIVE
  To evaluate the free radical generation and status of the antioxidant enzymes in murine peritoneal macrophage during in vitro vancomycin sensitive Staphylococcus aureus (VSSA) treatment with different time interval.
  
  
  METHODS
  Peritoneal macrophages were treated with 5×10(6) CFU/mL VSSA cell suspension in vitro for different time interval (1, 2, 3, 6, 12, and 24 h) and superoxide anion generation, NADPH oxidase activity, myeloperoxidase activity, nitric oxide generation, antioxidant enzyme status and components of glutathione cycle were analyzed.
  
  
  RESULTS
  Superoxide anion generation, NADPH oxidase activity, myeloperoxidase activity and nitric oxide generation got peak at 3 h, indicating maximum free radical generation through activation of NADPH oxidase in murine peritoneal macrophages during VSSA infection. Reduced glutathione level, glutathione peroxidase, glutathione reductase, and glutathione-s-transferase activity were decreased significantly (P<0.05) with increasing time of VSSA infection. But the oxidized glutathione level was time dependently increased significantly (P<0.05) in murine peritoneal macrophages. All the changes in peritoneal macrophages after 3 h in vitro VSSA treatment had no significant difference.
  
  
  CONCLUSIONS
  From this study, it may be summarized that in vitro VSSA infection not only generates excess free radical but also affects the antioxidant status and glutathione cycle in murine peritoneal macrophages.
authors.affiliation: Immunology and Microbiology Laboratory, Department of Human Physiology with Community Health, Vidyasagar University, Midnapore-721 102, West Bengal, India.
authors.forename: Subhankari Prasad
authors.initials: SP
authors.lastname: Chakraborty
authors.affiliation: Immunology and Microbiology Laboratory, Department of Human Physiology with Community Health, Vidyasagar University, Midnapore-721 102, West Bengal, India.
authors.forename: Somenath
authors.initials: S
authors.lastname: Roy
keywords: Antioxidant enzyme; Oxidative stress; Peritoneal macrophage; Vancomycin sensitive Staphylococcus aureus