advertisement
Abstract #22293 Published in IGR 10-4
Prooxidant-antioxidant balance, peroxide and catalase activity in the aqueous humour and serum of patients with exfoliation syndrome or exfoliative glaucoma
Koliakos GG; Befani CD; Mikropoulos D; Ziakas NG; Konstas AGGraefe's Archive for Clinical and Experimental Ophthalmology 2008; 246: 1477-1483
BACKGROUND: Oxidative stress plays an important role in the pathobiology of exfoliation syndrome (XFS) and exfoliative glaucoma (XFG). METHODS: We investigated the prooxidant-antioxidant balance (PAB) in aqueous humour and serum samples of 20 consecutive cases of XFS, 20 of XFG, and 20 age-matched controls, employing a recently described novel assay. The activity of catalase and the levels of (hydrogen) peroxide were also measured in these samples. RESULTS: There was no significant difference between the PAB in the aqueous humour of the XFS group (82.5 ± 10 AU) and age-matched control patients (78.9 ± 13.4 AU; p > 0.05). A significant shift of the PAB balance in favour of oxidants was detected in the XFG group (90.2 ± 7.6 AU) compared with controls (p < 0.001). In the serum of patients with XFS (138.8 ± 13.2 AU) and XFG (124.08 ± 13.50 AU), PAB was significantly altered in favour of oxidants as compared to age-matched controls (114.9 ± 9.91 AU); p < 0.001). Catalase activity in the aqueous from XFS (10.1 ± 4.5 U/ml) and XFG (12.2 ± 6 U/ml) patients was significantly lower than that measured in the normal aqueous (14.6 ± 1.9 U/ml). Similarly, a significantly lower catalase activity was found in XFS (103 ± 21.4 U/ml) and XFG (116 ± 38 U/ml) serum samples compared with controls (189.6 ± 84.3 U/ml). Finally, (hydrogen) peroxide concentration in aqueous and serum samples from patients with XFS (aqueous: 26.9 ± 6.6 μM; serum: 41 ± 10 μM) and XFG (aqueous: 21.7 ± 7 μM; serum: 32 ± 4 μM) were significantly higher than that of the controls (aqueous: 9.6 ± 5.8 μM; serum: 24 ± 9 μM; p < 0.001). CONCLUSIONS: These findings suggest that in XFS oxidative stress is counterbalanced in the aqueous, whereas the development of XFG is accompanied by a disruption of this balance in favour of oxidants.
Dr. G.G. Koliakos, Department of Biological Chemistry, Medical School, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece. koliakos@med.auth.gr
