Protecting effect of epigallocatechin-3-gallate on apoptosis in SK-N-SH cells induced by paraquat

AIM To investigate the protecting effect of epigallocatechin-3-gallate (EGCG) on apoptosis of human neuroblastoma (SK-N-SH) cells induced by paraquat. METHODS SK-N-SH cells were cultured and the cell apoptosis was induced by 400 μmol·L-1 paraquat. The cells were randomly divided into 6 groups: blank control group, paraquat model group, vitamin E (10 μmol·L-1) group and 3 EGCG (1, 5, and 10 μmol·L-1) groups. After treatment with Vitamin E and different concentration of EGCG for 2 hours respectively, 400 μmol. L -1 paraquat was added to the SK-N-SH cell cultured for 72 hours. Then MTT was used to determine the conditions of cells viability, and the supernatant was taken to determine the leakage of LDH. The morphological change and rate of cell apoptosis were detected by Hoechst 33258 staining and flow cytometry, respectively.RESULTS Compared with the blank control group, paraquat could reduce the cell viability ( P 0.01),increase the leakage of LDH (P 0.01), cause cell membrane breakage and vacuole, and induce apoptosis with a rate of occurrence up to 30.5%. With pre-treatment of EGCG, cell archaeus could be enhanced (P 0.01 or P 0.05), the leakage of LDH was reduced (P 0.01), and the rate of occurrence in cell apoptosis droped (P 0.01) significantly. And the effects of 10 μmol·L-1 EGCG group had significant difference with those of 5 μmol·L-1 group or 1 μmol·L-1 group (P 0.05 or P 0.01) . CONCLUSION EGCG can inhibit apoptosis of SK-N-SH cells induced by paraquat.