Purpose: To describe the protective effect of anthocyanin from black soybean in human lens epithelial cell line (HLE-B3) under H2O2-induced oxidative stress.
Methods: Cytotoxicity of anthocyanin and H2O2 were determined by Cell Counting Kit-8 test. Viability of HLE-B3 cells under various H2O2 concentration (0, 50 and 100 μM) with or without pretreatment of anthocyanin (0, 50, 100 and 200 μg/ml) was measured. After quantifying the percentage of the apoptosis by Annexin V assay and APO-BrdU TUNEL assay, we conducted western blot and immunostaining of apoptosis-related molecules; Bcl2, BAD, BAX, p53 and caspase-3. To confirm the effect of anthocyanin on an ex vivo model, its effect on cultures of the lenses of porcine were examined.
Results: Anthocyanin reduced cell death of HLE-B3 under H2O2-induced oxidative stress in a dose-dependent manner. In Annexin V analysis, anthocyanin protected HLE-B3 cells from apoptosis. H2O2 increased the expression of BAX, BAD, p53 and caspase-3 in a time-dependent manner, those of which anthocyanin significantly decreased. On the other hand, Bcl2 was increased from anthocyanin-treated lens cells. And in anthocyanin-treated lens organ culture, transparency was maintained.
Conclusions: This study showed that anthocyanin protects HLE-B3 cells under oxidative stress from apoptosis, and the mechanism of the effect is related to the intrinsic pathway of apoptosis. Anthocyanin has a potential in prevention of cataract.
Keywords: Anthocyanin; apoptosis; cataract; human lens epithelial cells; oxidative stress.