The Studyof Anti-experimental Liver Fibrosis And Liver Injury Action Of Diammonium Glycyrrhizinate

ObjectiveTo investigate the prophylactic effect of Diammonium glycyrrhizinate(DG) on experimental liver fibrosis in rats induced by dimethylnitrosamine(DMN), and to observe the effect on expression of MMP-2. MTT colormetric assay was used for evaluating the inhibitive effect of DG on HSC-T6, and the secretion of typeⅠcollagen and TGF-β1 were detected by ELISA method. acute liver injury in mice induced by D-galactosamine (D-GalN) was used to evaluate the interfere therapeutic effects of DG, to provide the proof for clinical using to treat liver fibrosis and liver injury.Experimental contents1. Prophylactic effects of Diammonium Glycyrrhizinate on liver fibrosis in rats induced by dimethylnitrosamineBy establishing the models of DMN-induced liver fibrosis in rats, we observed the prophylactic effect of Diammonium glycyrrhizinate with high and low dosage group (60gmg/kg and 15gmg/kg, respectively), and colchicinum as the positive control. Serum Index of liver function, contents of hydroxyproline(Hyp) and malodialdehyde (MDA) in liver tissue were assayed, serum levels of hyaluronic acid (HA) and laminin(LN) were determined, the liver pathological change and the expression of matrix metalloproteinases-2(MMP-2)was observed. It showed that serum levels of ALT, AST,ALP and TBIL in both dosage groups of Diammonium glycyrrhizinate were all obviously lower to those of model group (P<0.01). Contents of Hyp, MDA in liver tissue and HA, LN in serum were remarkable lower to those of model group(P<0.01) and colchicinum group(P<0.05,0.01). Hepatic fibrosis histopathological changes were remarkable alleviated in high and low dosage groups of Diammonium glycyrrhizinate comparing with those of model group (P<0.05). the expression of MMP-2 in liver tissue of both groups of Diammonium glycyrrhizinate were significant increasing comparing with those of model group(P<0.05). It showed that Diammonium glycyrrhizinate has a remarkable prophylactic effect on DMN-induced liver fibrosis in rats, its mechanisms were realated to anti-lipopeioxidation, protecting hepatocytes, prompting the degradation of collagens and suppressing expression of MMP-2.2. The effect of Diammonium glycyrrhizinateon inhibiting the proliferation of HSC-T6 and the secretion of typeⅠcollagen and TGF-β1HSC-T6 were cultured and MTT colormetric assay was used for evaluating the inhibitive effect of Diammonium glycyrrhizinate. Comparing with the control group, it showed that Diammonium glycyrrhizinate has remarkable effect of inhibiting the proliferation of HSC-T6 above the concentration of 20.0μg/ml(P<0.01), and showed significant dose-effect relationship. Afetr treat the HSC-T6 for 24h,48h and 72h, IC50 of Diammonium glycyrrhizinate were 277.1μg/ml,160.7μg/ml and 86.5μg/ml respectively.HSC-T6 were cultured and divided into 4 groups randomly:The control group, high, middle and low dosage group (320.0μg/ml,80.0μg/ml,20.0μg/ml, respectively) of Diammonium glycyrrhizinate, the secretion of typeⅠcollagen and TGF-βlwere detected by ELISA method. Comparing with the control group, it showed that high, middle and the low dosage groups of Diammonium glycyrrhizinate all have remarkable effect of decreaseing the level of typeⅠcollagen and TGF-β1 in the cultured supernatant(P<0.01), and showed significant dose-effect relationship.3. Protective Effects of Diammonium glycyrrhizinate (DG) on Hepatic Injury in Mice Induced by D-galactosamineAcute liver injury in mice induced by D-galactosamine (D-GalN) was used to evaluate the interfere therapeutic effects of DG with high and low dosage group(120gmg/kg,30mg/kg, respectively), and Bifendate(150gmg/kg)as the control. Serum ALT, AST and superoxide dismutase (SOD) activity were observed, Histopathologycal examination was also performed for liver tissue. It showed that serum ALT and AST activity in all groups of DG were obviously decreased and SOD activity were increased compared with that of model group (P<0.05,0.01). Serum ALT and AST activity in high dosage group of DG were obviously decreased and SOD activity were increased compared with that of low dosage group(P>0.05), but no significant difference were observed comparing with the Bifendate group(P>0.05). Hepatic histopathological changes were alleviated in all groups of DG.It showed that DG has a good protective effects on liver injury in mice induced by D—GaiN, its therapeutic mechanism is related to the antioxidation.Conclusion1. Diammonium glycyrrhizinate possess the prophylactic effects of anti-liver fibrosis in rats induced by DMN, its mechanisms were realated to anti-lipopeioxidation, protecting hepatocytes, prompting the degradation of collagens and suppressing expression of MMP-2.2.Diammonium glycyrrhizinate have remarkable effect of inhibiting the proliferation of HSC-T6, can strongly inhibit the secretion of type I collagen and TGF-β1.3. Diammonium glycyrrhizinate has a good protective effects on liver injury in mice induced by D—GaiN, its therapeutic mechanism is related to the antioxidation. Key words:Diammonium glycyrrhizinate, liver fibrosis, liver injury, HSC-T6,...