Nitric oxide and tumour necrosis factor alpha in the process of pseudoexfoliation glaucoma

AIM: To establish the role of nitric oxide (NO), ascorbic acid and tumour necrosis factor alpha (TNF-alpha) in the pathogenesis of pseudoexfoliation glaucoma (XFG). METHODS: Our study included 120 patients who were referred for cataract surgery. All patients were divided into four groups according to clinical findings: XFG, early and late pseudoexfoliation syndrome (XFS), and cataract (without pseudoexfoliation). Serum and aqueous humour levels of the ascorbic acid, NO and TNF-alpha were measured. The concentrations of the ascorbic acid and NO were measured by an appropriate spectrophotometric method. Enzyme-linked immunosorbent assay (ELISA) was used to determine TNF-alpha level. RESULTS: Aqueous humour concentration of ascorbic acid was significantly lower in patients with late XFS (0.61 +/- 0.11 mmol/L) and XFG (0.48 +/- 0.15 mmol/L) compared to patients with early XFS (0.9 +/- 0.15 mmol/L) and cataract (1.16 +/- 0.22 mmol/L), while there was00 no difference in serum concentration in all examined groups. Aqueous humour concentration of NO was significantly higher in patients with XFG (77.7 +/- 11.4 mu mol/L) compared to patients with early XFS (50.27 +/- 9.34 mu mol/L) and cataract (49.77 +/- 7.1 mu mol/L), while serum concentration was increased in the early stage of XFS (73.26 +/- 8.29 mu mol/L). Aqueous humour level of proinflammatory cytokine TNF-alpha was increased in patients with XFS (early 460.04 +/- 18.32 pg/mL; late 502.42 +/- 53.23 pg/mL) and XFG (510.34 +/- 43.07 pg/mL), while there was no difference in serum level in all examined groups of patients. CONCLUSION: Reduced ascorbic acid and elevated NO and inflammation related cytokine TNF-alpha level in aqueous humour of the patients with developed XFG suggest that oxidative stress induces local inflammation.