方法：分别用不同浓度的α-倒捻子素和H₂O₂处理ARPE-19，CCK8法检测α-倒捻子素和H₂O₂对ARPE-19细胞毒性作用。不同浓度的α-倒捻子素预处理ARPE-19，再用200μmol/L H₂O₂处理24h，观察细胞活性变化。流式细胞仪检测细胞活性氧(reactive oxygen species， ROS)水平变化，免疫印迹法(Western blot)检测NF-κB蛋白表达变化。

结果：CCK8法检测结果显示：当α-倒捻子素浓度在0～12μmol/L时，ARPE-19活性无明显变化； 当浓度达到16μmol/L时，细胞活性开始下降(P<0.05)。H₂O₂诱导后，当α-倒捻子素浓度在0～16μmol/L之内时，α-倒捻子素预处理均可提高ARPE-19细胞活性。ROS结果表示：H₂O₂诱导后，ROS表达量增高(P<0.05)； 8和12μmol/L α-倒捻子素预处理，均可有效清除H₂O₂诱导产生的ROS(P<0.05)。Western blot结果显示：H₂O₂诱导后NF-κB蛋白表达增高(P<0.05)，12μmol/Lα-倒捻子素预处理可以继续上调H₂O₂诱导后ARPE-19的NF-κB蛋白表达(P<0.05)。

结论：H₂O₂诱导ARPE-19细胞氧化损伤，造成细胞活性下降，ROS表达量增加，经过α-倒捻子素预处理后，可有效提高细胞活性，清除ROS，活化NF-κB。

METHODS:ARPE-19 cells were treated with different concentrations of α-Mangostin and H₂O₂.The effect of α-Mangostin and H₂O₂ respectively on cell activity was detected by CCK8. ARPE-19 cells were pretreated with different concentrations of α-Mangostin for 24h before they were administrated with 200μmol/L H₂O₂for another 24h.Then the changes of cell activity were observed. The expression of reactive oxygen species(ROS)level was detected by flow cytometry(FCM)and the expression of NF-κB protein was measured by Western blot analysis.

RESULTS:CCK8 examination results showed that: within 0～12μmol/L, α-Mangostin had no damage effects on cell activity. When the concentration of 16μmol/L, cell viability began to decrease(P<0.05).And α-Mangostin pretreatment gradually increased cell viability of ARPE-19 induced by H₂O₂ when the concentrations of α-Mangostin were within 0～16μmol/L. ROS results showed: the expression of ROS level significantly increased after H₂O₂ induced(P<0.05); 8 and 12μmol/L α-Mangostin pretreatment down-regulated ROS expression of ARPE-19 induced by H₂O₂(P<0.05). Western blot results showed that the expression of NF-κB protein after H₂O₂ induced increased(P<0.05); 12μmol/L α-Mangostin pretreatment up-regulated NF-κB of ARPE-19 induced by H₂O₂(P<0.05).

CONCLUSION: H₂O₂ induced oxidative damage in RPE cells by decreasing cell viability and increasing the expression of ROS level. α-Mangostin can protect RPE cells from the injury of H₂O₂, the mechanism may be related to the clear of ROS and the activation of NF-κB.