Investigation of oxidative stress in pterygium tissue

PURPOSE: To investigate changes in the oxidant-antioxidant system in pterygium tissue. METHODS: Tissue samples ablated from 40 patients during pterygium surgery constituted the study material, while normal nasal conjunctiva tissue samples from 20 patients matched for age group (who had undergone surgery for strabismus or extracapsular cataract surgery) were used as controls. The samples were kept at −70 °C until the time of analysis. Catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) enzymatic activity and the levels of nitric oxide (NO) and malone dialdehyde (MDA) were studied in both groups. RESULTS: The mean age was 54.0±12 years in the pterygium patients and 49.0±19 in the controls (p=0.270). The enzyme activity levels were significantly lower in the pterygium group when compared to the controls (p<0.001 in each case), while in the same group a significant increase was observed in the MDA and NO levels (also p<0.001, in both cases). CONCLUSIONS: These findings indicating oxidative stress in the pterygium tissue suggest that oxidative stress can play a role in pterygium etiopathogenesis.