Antioxidant Enzymes in Tears Among Malay Age-related Macular Degeneration Patients

ABSTRACT

@#Introduction: Age-related macular degeneration (ARMD) is an ocular degenerative disorder that associated with impairment of central vision. Oxidative stress plays an important role in the pathogenesis of ARMD. The aim of this study was to determine the level of antioxidant enzymes (catalase and glutathione peroxidase) in tears among Malay ARMD patients. Methods: A cross sectional study was conducted between September 2015 and November 2017 among Malay ARMD patients. Schirmer paper was used to collect the tear samples. The level of catalase and glutathione peroxidase level in tears was evaluated using commercially available oxidative stress marker kits. Results: A total of 136 Malay ARMD patients were recruited into the study with 68 controls. Mean tear catalase and glutathione peroxidase levels were significantly lower in ARMD patients (1348.97 SD 109.11 µM and 453.87 SD 41.96 U/L respectively) as compared to the control group (1453.38 SD 38.87 µM and 502.28 SD 34.29 U/L respectively) (P<0.001 and P<0.001 respectively). Late ARMD has lower mean of catalase level in tears as compared to early ARMD (P=0.044). Based on subtypes of neovascular late ARMD, neovascular ARMD has lower mean catalase level in tears compared to idiopathic polypoidal choroidal vasculopathy (IPCV) (P=0.031). Conclusion: This study showed that antioxidant enzyme might play an important factor in the pathogenesis of ARMD.