Effects of MgIG on the apoptosis of hepatocytes induced by simulated hypoxia reperfusion in rats

Abstract

Objective To observe the effects of magnesium isoglycyrrhizinate (MgIG) on the apoptosis of hepatocytes induced by simulated hypoxia reperfusion in rats and related mechanism.Methods Hepatocytes of the rats were isolated,cultured and identified,then,the liver cells in logarithmic growth phase were randomly divided into 4 groups:the hypoxia reperfusion injury model group,the low MgIG group (0.1 g/L),the moderate MgIG group (1 g/L) and the high MgIG group(10 g/L).Twenty-four hours after pre-treatment (exposure to simulated hypoxia for 6 h and re-perfusion for 4 h),following measurements were performed.① Changes in cell morphology were observed by optical microscopy.② Effects of MgIG on the vitality of hepatocytes were detected by MTT.③Apoptosis and rate of apoptosis were detected and calculated by AO/EB.④The expression levels of bcl-2 and Bax in all the groups were monitored by real time quantitative fluorescence PCR (RT-qPCR).Then,the detected data were analyzed by SPSS17.0.T test was applied for the comparison of the two mean sample lots,and single-factor ANOVA was used for the comparison of multiple samples.Results ①MTT assay indicated that MgIG at some concentrations (0.1,1 and 10 g/L)could improve the A value of the damaged hepatocytes induced by ischemia and re-perfusion(0.285 ± 0.017,0.320 ± 0.008 and 0.341 ± 0.019),as compared with that of the model group,with statistical significance (P ＜ 0.01).②AO/EB staining revealed that apoptosis rates in the low,moderate and high MgIG groups were(0.5763 ± 0.0405,0.2866 ±0.0619 and 0.1261 ±0.0439),which were all lower than that of the control group (0.7124 ± 0.0581),also with statistical significance (P ＜ 0.05).③RT-qPCR monitoring indicated that the expression levels of bcl-2 mRNA in the low,moderate and high MgIG groups (3.350 ± 0.151,9.279 ± 0.350 and 15.290±0.756) were all higher than that of the control group (0.928 ± 0.068),also with statistical significance(P ＜0.01).The expression levels of Bax mRNA in the low,moderate and high MgIG groups (0.743 ± 0.035,0.265 ± 0.065 and 0.119 ± 0.019)were all lower than that of the control group (0.945 ± 0.063),with statistical significance as well (P ＜ 0.01)Conclusions MgIG could increase the vitality of damaged hepatocytes induced by hypoxia-reperfusion and decrease rate of apoptosis,the mechanism of which might be associated with higher expression of bcl-2 mRNA and lower expression of Bax mRNA. Key words: Magnesium isoglycyrrhizinate; Hepatocyte; Hypoxia, reperfusion