Purpose: to assess the role of oxidative stress as a risk factor and antioxidant enzymes as a protection factor against age related cataract.
Methods: in a prospective study 20 patients with senile cataract and 10 control subjects were selected and matched. The levels of glutathione peroxidase (GPx) enzyme and catalase enzyme were measured in erythrocytes, and total antioxidants were measured in plasma. All results were compared by student's "t" test and Chi-square analysis (P<0.05 for significance).
Results: the levels of erythrocyte GPx activity in patients and control group were found a mean value of 108.96±32.46 mu/ml and 194.68 ± 8.74 mu/ml, respectively (P<0.01) highly significant. Catalase level was 0.111 ± 0.033 u/ml in patients and 0.118 ± 0.037 u/ml in control group which was statistically non-significant (P > 0.05). Total antioxidant levels of patient and controls were 0.99 ± 0.243 mM/L and 1.088±0.283 mM/L, respectively (P>0.05) non-significant.
Conclusion: The role of antioxidant enzymes in the protection against senile cataract formation is still controversial. As the result of this study, glutathione peroxidase enzyme is found to be the most important enzyme over the other antioxidants as a strong correlation was found between the low levels of GPx in erythrocytes and the development of senile cataract. However large multi-center studies are required before establish this concept.