EGCG对氧化应激诱导的大鼠NRK细胞Nrf2和γ-GCS基因表达的影响

Effect of epigallocatechin-3-gallate （ EGCG ） on the expressions of nuclear factor-E2 related factor2 （Nrf2） and γ-glutamylcystein synthase （γ-GCS） in renal tubular epithelial ceils of rats with oxidative stress

下载PDF阅读器目的 研究表没食子儿茶素没食子酸酯（EGCG）对过氧化氢（H2O2）诱导的肾小管上皮细胞（NRK）抗氧化反应的机制.方法 将培养细胞分正常对照组、H2O2模型组、EGCG治疗组.MTT法检测细胞活力,实时定量PCR法检测NRK细胞核因子-E2相关因子2（nuclear factor-E2 related factor2,Nrt2）mRNA和γ-谷氮酰半胱氨酸合成酶（γ-glutamylcystein synthase,γ-GCS）mRNA表达,免疫组化法检测NRK细胞中Nrf2、γ-GCS蛋白的表达,Western blot法测定NRK细胞Nrf2、γ-GCS蛋白表达量.结果 正常对照组NRK细胞的活性为97.61±6.33,模型组NRK细胞的活性明显降低（56.38±5.57）（P〈0.01）.当EGCG浓度分别为5、10、20 me,/L时,细胞活性为77.42±5.31、83.27±5.94、90.24±5.72,明显高于模型组（P〈0.05,P〈0.01）.EGCG可以上调NRK细胞Nrf2和γ-GCS mRNA和蛋白的表达,且具有剂量依赖性.结论 氧化应激能导致大鼠NRK活力下降,凋亡增加,EGCG通过促进Nrf2、γ-GCS表达的增加,提高NRK细胞的抗氧化能力,促进氧化应激后损伤的修复.

Objective To investigate the mechanism of antioxygen reaction of epigaUocatechin-3- gallate （EGCG） in renal tubular epithelial cells of rats with oxidative stress induced by H2 02. Methods Cultured ceils were divided into control group, H202 group and EGCG group. Cell survival was observed with MTT. The expressions of Nrf2 mRNA and γ-GCS mRNA in cultured cells were examined by real time quantitative PCR. Immunohistochemistry and western blotting were used to detecte the expressions of Nrf2 and γ-GCS protein. Results The survival rate of tubular cells was 97.61 ± 6. 33 in control group. There was a significant decrease in 1-1202 group （56. 38 ±5.57） （P 〈0. 01 ） ,while increased when the EGCG concentration were 5,10,20 mg/L（77.42 ± 5.31,83.27 ± 5.94,90. 24 ± 5.72） （ P 〈 0. 05, P 〈 0. 01 ）. EGCG up-regulated the expressions of Nrf2 and γ-GCS mRNA and protein in renal tubular epithelial cells with dose dependentrnent. Conclusion The expressions of Nrf2 and γ-GCS increase in renal tubular epithelial cells with oxidative stress. Resulting from suppression of oxidative stress, EGCG exerts protective effect on NRK, and this antioxidative effect may be partly induced by activating the Nrt2 signal pathway.