Protective effects of green tea catechins against diabetogenic cataract by inhibiting lens oxidative stress and aldose reductase activity

Aim and Objectives: The present study was designed to evaluate the anticataract activity of green tea catechins like green tea extract (GTE), catechin, and epigallocatechin gallate (EGCG) against glucose-induced cataract model in goat lens. Methodology: The goat lenses were incubated in artificial aqueous humor containing a high concentration of glucose (55 mM) with green tea catechins at different concentrations (50, 100, and 200 µg/mL) and after eight hours anticataract activity was assessed against the glucose control group contains a high concentration of glucose only. The antioxidant activity was assessed by using DPPH and hydrogen peroxide assay. The aldose reductase inhibitory activity was performed using an ex-vivo model in goat lenses. Results and Discussion: The results showed green tea catechins considerably retained the lens transparency and reduced the progression of cataract maturation. Green tea catechins significantly restore the lenticular oxidative stress markers (CAT, SOD, GSH, and MDA) and protein contents, when compared to the glucose control group. Moreover, results indicated that EGCG had better anticataract activity than GTE and catechin, which might be due to its potent and better antioxidant and aldose inhibitory activity, which was observed in the study. Conclusion: The results concluded that green tea catechins, particularly EGCG, efficiently prevent or delay cataract development and might be a potential candidate in the future.