Antioxidative enzymes in human nasal mucosa after exposure to ozone. Possible role of GSTM1 deficiency

Abstract:

Objective and design: Epithelial antioxidative enzymes (AOEs) are thought to be a first line of defense against reactive oxygen species as they are upregulated after exposure to ozone according to animal studies. We analysed the activities of the AOEs catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), superoxide dismutase (SOD) and glutathione-S-transferase (GST) in a tissue culture of human nasal mucosa and analysed the influence of GSTM1 polymorphism on AOE regulation.¶Methods: Tissue biopsies of 20 subjects were incubated for 24 h with and without 120 ppb ozone. Activities were assayed to determine what enzymatic changes had taken place, both overall and in regard to GSTM1 status.¶Results: Activities for GPX (p = 0.272) and SOD (p = 0.291) were found increased after ozone exposure. GSTM1-deficient patients showed a significantly enhanced upregulation of SOD activity (p = 0.011) compared to GSTM1 carriers.¶Conclusion: Our findings suggest that GSTM1-deficiency has an impact on AOE-regulation after ozone exposure.