Studies On The Treatment Effect Of Silymarin And Praziquantel Against Liver Fibrosis Of Schistosomiasis Japonicum

Schistosomiasis is a serious parasitic zoonosis,about239million people havebeen infected worldwide. There is only an epidemic of Schistosoma japonicumoccurred. The most prominent injury of schistosomiasis to human is the deposition ofscar tissue around parasite eggs trapped in the liver. At present, Praziquantel is themost effective drug for schistosomiasis.This agent can efficiently kill adult worms,butcann’t kill the eggs.The remained eggs can continue to release soluble eggantigen,which cause liver fibrosis.Therefore,the early and effective treatment againstliver fibrosis for chronic schistosomiasis is very important.Currently,there is no effective chemical drug to treat liver fibrosis,but naturalmedicine has showed great advantage in this aspect.Silymarin is flavonoid lignanscompounds extracted from milk thistle,with protective effect on a variety of liverinjury.The treatment of hepatic fibrosis of schistosomiasis with Silymarin andPraziquantel is very limited now.The mice infected with Schistosoma japonicum wasused as model to investigate the treatment effects of Silymarin and Praziquantelagainst liver fibrosis of schistosomiasis japonicum in this study.This study was divided into two parts as follows:Part1, Construction of hepatic fibrosis model of mice with schistosomiasisjaponicum Mice were infected with Schistosoma japonicum cercaria using the bodyimmersion technique. Infected mice were killed6,8,10and12weeks post infectionrespectively.Pathological and histological parameters that reflect disease severity wereexamined.Acute inflammatory granuloma and a lesser collagen deposition were seen in thehepatic parenchyma6weeks post infection.With the development of infection, morecollagen deposition around the granuloma appeared significantly12weeks postinfection.Part2, Studies on the treatment effects of Silymarin and Praziquantelagainst liver fibrosis of schistosomiasis japonicumMice were divided into7groups,(A)uninfected control group,(B) infected butuntreated group,(C) treated with Praziquantel,(D) treated with Silymarin,(E) treatedwith Praziquantel and small dose of Silymarin,(F) treated with Praziquantel andmiddle dose of Silymarin,(G) treated with Praziquantel and large dose of Silymarin.Concentrations of ALT and AST in the collected sera were estimated using theavailable commercial kits.MMP-2and TGF-β1were estimated in the liver usingWestern blot. Pathological and histological parameters that reflect disease severitywere examined.Compared with infected untreated group, the mice treated with Silymarin andPraziquantel showed a significant decrease in serum levels of ALT（P<0.01）and AST（P<0.01）, caused a significant reduction of MMP-（2P<0.05）and TGF-β（1P<0.05）in the liver.The results indicated that Silymarin and Praziquantel have been protective effectagainst liver fibrosis of schistosomiasis japonicum. Silymarin might be a promisinganti-fibrosis agent against liver fibrosis of schistosomiasis jiaponicum.