穿心莲内酯调控HaCaT细胞中Nrf2/ARE通路的抗氧化作用机制研究

Anti-Oxidation Mechanism of Andrographolide on HaCaT Cells Via Nrf2/ARE Pathway

目的探讨穿心莲内酯通过诱导Ha Ca T细胞中Nrf2/ARE信号通路介导的HO-1、NQO1、AKR1C1的表达,减少细胞因氧化应激而受到的损伤。方法通过CCK-8方法检测穿心莲内酯对Ha Ca T细胞的活力影响以及过氧化氢诱导的细胞存活率的影响。用穿心莲内酯不同浓度预处理Ha Ca T细胞24 h,分别通过Western blot以及实时荧光定量PCR分析检测Ha Ca T细胞中Nrf2、HO-1、AKR1C1、NQO1的表达水平;通过胞质胞核分离以及免疫荧光的方法分析Nrf2蛋白核内表达情况。结果穿心莲内酯不影响细胞存活率,并剂量依赖性的降低H2O2诱导的细胞死亡,差异具有统计学意义。穿心莲内酯能显著增强抗氧化酶Nrf2、HO-1、AKR1C1、NQO1的蛋白和mRNA表达,增加Nrf2的细胞核内的分布,并上调ARE的表达活性。穿心莲内酯能够上调上游蛋白激酶AMPKα的磷酸化(p-AMPKα)水平。结论穿心莲内酯降低H2O2诱导的细胞死亡,其作用机制可能是通过激活Nrf2/ARE信号通路,从而调控HO-1、AKR1C1、NQO1的表达水平。

OBJECTIVE To investigate the anti-oxidant mechanism of andrographolide on HaCaT cells via Nrf2/ARE signal pathway. METHODS The effect of andrographolide on the viability of HaCaT cells and the effect of H2O2-induced cell viability were measured by CCK-8. HaCaT cells were pretreated with andrographolide of different concentration for 24 h. The protein and mRNA expression levels of Nrf2, HO-1, AKR1C1 and NQO1 in HaCaT cells were detected by Western blot and RT-qPCR, respectively. The expression of Nrf2 protein in the nucleus was analyzed by nuclear cytoplasmic separation and immunofluorescence. RESULTS Andrographolide had no significant effect on cell viability and dose-dependently decreased H2O2-induced cell death, the difference was statistically significant. Andrographolide significantly enhanced the expression of protein and mRNA of antioxidant enzymes Nrf2, HO-1, AKR1C1, NQO1, increased the distribution of Nrf2 in the nucleus, and up-regulated the expression of ARE. Besides, andrographolide upregulated the phosphorylation level of the upstream protein kinase AMPKα(p-AMPKα). CONCLUSION Andrographolide could decrease H2O2-induced cell death, and its mechanism may be through the activation of Nrf2/ARE signaling pathway, thereby regulating the expression levels of HO-1, AKR1C1, and NQO1.