Molecular Mechanisms Of The In Vitro Antiviral And Immunoregulation Effect Of Compound Glycyrrhizin

ObjectiveCumulative clinical studies have been proved that the Compound Glycyrrhizin (CG) has many biological and pharmacologic functions which include anti-inflammatory, antiviral, anti fibrosis and immunoregulation, especially antiviral and immunoregulation. Howerver, there was not publication focused on the molecular mechanisms of antiviral effect of Gompound Glycyrrhizin. The aim of the present paper is to explore the in vitro mechanisms of Glycyrrhizin, which might provide novel data for further understand of its multiple pharmacologic effects.MethodsFour cell lines (e.g., A549, Mela, SMMC-7721and TC-1), which were originally selected from different tissues and species, were employed in this research. The cell proliferation was detected by MTT, the expression levels of IFN-1M, IRF3, ISG15gene were assayed through RT-QF-PCR, the amont of1FN-61,1SG15and Mx protein were detected by Western blot, and the concentrations of IL-29, IL-12and IFN-y were analyzed by HL1SA approach. Finally, all experimental data was statistically analyzed by SPSS13.0.Results and DiscussionResults of MTT displayed that Compound Glycyrrhizin induced proliferation of TC-1cells was faster than that of A549and Hela cells. Totally, at48h of CG co-culture, the relative growth rates of four cells were from50%through70%with80μg/ml of CG. Such concentration was utilized for further experiments.RT-QF-PCR results demonstrated that the expression peaks of IFN-β1, IRF3and ISG15gene of A549and Hela cells were presented at12h CG co-culture. On the other hand, the expression peaks of above antiviral genes were somewhat smoother in SMMC-7721and TC-1cells. In generally, CG could induce the expression of core antiviral genes in four cell lines in time and dosage-dependent style.Results of Western blotting showed that the peak amont of IFN-β1protein in A549 and SMMC-7721cells were arrived at24h post CG culture, and at48h in Hela and TC-1cells, compared with that of the control group (P<0.05). The peak volumes of ISG15protein were displayed at24h CG culture in A549, Hela and TC-1cells (P<0.05), and48h in SMMC-7721cells (P<0.05). The peak amount of Mx protein was showed at24h of CG culture in A549and Hela cells, and48h in SMMC-7721and TC-1cells. Which suggest the markedly induce effects of CG upon the antiviral proteins.Results of ELISA assays demonstrated that CG can enhance the expression of IL-29in cell lines A549and Hela, which arried the summit level at12h post CG co-culture (P<0.05), but no significant difference was observed in that of SMMC-7721and TC-1(P>0.05). However, there wasn’t statistical difference of IL-12and IFN-γ amount after CG culture in these cell lines.ConclusionCG could induce the expression of IFN-β1, IRF3and ISG15gene in four cell lines largely in the same style, suggesting a key pathway due to the antiviral and immunoregulation effect of CG. The increasing of IL-29expression in certain cell lines after CG co-culture may indicate the importance of this antiviral cytokine responsible for the pharmacologic action of CG. In summary, works presented in this thesis demonstrate the antiviral and immunoregulation effect of CG may conduct by key elements such as IRF3/IFN-β1/ISG15pathway and IL-29approach.