Résumé
Objective:To observe the influence of ginsenoside Rg1 on transcriptional activation of NF-κB induced by hydrogen peroxide (H_2O_2) in 293T cell,and probe into the antioxidant mechanism of ginsenoside Rg1.Methods:In the experiment,cells was exposed to H_2O_2 after pretreatment with Rg1,cell proliferation and cytotoxicity studies were detected by MTT and Trypan blue.The quantities of generation of intracellular reactive oxygen species (iROS) was analyzed by flow cytometric analysis measured with fluorescent probe 2,7-dichlorofluorescin diacetate (DCFH-DA).NF-κB-responsive element-luciferase reporter gene was transfected and dual-luciferase cis-reporting systems were used to assay the transcriptional activity of NF-κB under the stimulated circumstance of oxidative stress induced by H_2O_2.Results:The results of MTT showed that ginsenoside Rg1 apparently protected the proliferation of 293T cell,which were repressed by H_2O_2 (P＜0.05).The results by trypan blue showed that H_2O_2 stimulated substantial cytotoxicity.This effect was markedly attenuated by treatment with ginsenoside Rg1.Oxidant production,measured as the fluorescence of dichlorofluorescein,was significant increased by 40%-50% through H_2O_2 stimulation.The decrease in iROS generation was significant blocked by 35%-40% through Rg1 and antioxidant.The relative luciferase reporter assay of NF-κB was apparently improved by H_2O_2-induced(P＜0.05),but Ginsenoside Rg1 significantly repressed the relative value of luciferase (P＜0.05).Conclusion:Ginsenoside Rg1 has the obvious protective function from the damage of oxidative stress damage,whose possible mechanism is to eliminate excessive free radicals of the cells effectively,to reduce transcriptional activation of nuclear factor kappa B(NF-κB),and subsequently to suppress the NF-κB circuit activation.
Résumé
0.05). Compared with control cells, the relative luciferase activity of NF-?B in virus-infected cells was apparently up-regulated (P