Objective: To investigate the effects of glycyrrhizin (GL) on the expression of hepatitis B virus e antigen (HBeAg), HBV DNA, Toll-like receptors 2,4 (TLR2,4) and proliferation of cells in HepG2.2.15 cell line.
Methods: Real-time PCR examined HBV DNA, ELISA examined HBsAg, HBeAg and MTT examined the proliferation of cells. FCM examined the positive percent of cells expressing TLR2,4 before and after stimulated with GL, in contrast to the blank group.
Results: The expression of HBsAg was low in the cell line, so e antigen was studied. The total HBeAg mean was significantly difference on the second day after stimulated (P<0.01), but only in the group with 400 microg/ml HBeAg decreased significantly in contrast to the blank group (P<0.05), the group with 800 microg/ml increased significantly in contrast to the other groups (P<0.01). The total HBV DNA mean on the third day after stimulated was significant, only the group with 50 microg/ml decreased in contrast to the blank group, but P>0.05, the other four groups increased. The intensity of TLR4 expression in the cells was significantly higher than that of the control group (P<0.05), both of total mean TLR2,4 increased significantly (P<0.01). The four groups except the group with 200 microg/ml increased significantly in no dose-dependent manner (P<0.05). GL in three goups under 200 microg/ml all could make cells proliferate, but only 200 microg/ml group had significant difference compared to the blank group (P<0.05). Both 400 and 800 microg/ml groups inhibited the growth of cells (P<0.01). The proliferation of cells were notably negative correlated with the expression of HBeAg, HBV DNA (P<0.05).
Conclusion: The study suggestes GL could inhibit or promote HBV DNA replicating and e antigen secreting in mutative HepG2.2.15 cell line, the correlation between the proliferation of cells and the both are negative. GL could upregulate TLR2,4 in no dose-dependent manner. Influencing HBV maybe have no correlation to up regulating TLR2,4 by GL at least in vitro.