Lipid peroxidation precedes TNF and PDGF release in alveolar macrophage of the experimental pulmonary fibrosis rats / 中国病理生理杂志

ABSTRACT

AIM: To evaluate the role of alveolar macrophage(AM)lipid peroxidation in bleomycin(BLM)-induced TNF-? and PDGF release from AM in rats. METHODS: Male SD rats were intratracheally instilled with saline or BLM(5 mg/kg body weight), and AM were isolated and analyzed for malondialdehyde (MDA) and glutathione peroxidase(GSH-Px) following 1,3,7,14 or 28 day (s).Simultaneously, TNF-? and platelet-derived growth factor(PDGF) were also determined in AM-conditoned media by ELISA and bioassay respectively. RESULTS:(1) MDA in AM was markedly increased on day 1,peaked on day 3 and then decreased to near control level on day 7; on the other hand, GSH-Px activity in AM were decreased to non-detectable levels during day 1-7 after BLM instillation, returned to the control level by day 14. (2) TNF-? and PDGF were increased significantly from the third day on and then exhibited a consectutive changes.(3)AM lipid peroxidation preceded TNF-? and PDGF release. CONCLUSION: Prior oxidative changes leading to AM lipid peroxidation,depletion of antioxidative pool might be essential for the subsequent mediators release in BLM-induced pulmonary fibrosis.