Study On The Mechanisms Of Magnesium Isoglycyrrhizinate In The Treatment Of Hepatotoxicity Induced By Methotrexate

Background and purposeMagnesium isoglycyrrhizinate(MgIG)is a compound synthesized from 18-?glycyrrhetinic acid extract of Glycyrrhiza uralensis Fisch extract.A large number of studies have confirmed that MgIG has good liver protection activity,and its injection has been clinically used to treat chronic viral hepatitis and improve abnormal liver function.The research group early evaluated the protective effect of MgIG on multiple chemotherapeutic drug-induced liver injury models.In our previous research,we found that MgIG can protect the liver and intestinal injury of rats induced by methotrexate(MTX)Has a good protection.We further found through the research literature that gastrointestinal injury is one of the most common adverse reactions of MTX,and changes in intestinal microbes and intestinal mucosa often cause or aggravate liver damage.Because the liver is directly connected to the intestine through the portal vein,it is the first organ to receive nutrients from the blood of the intestine,and the liver is also the first to receive microbiota-associated molecular patterns(MAMP)from the gut and organs that interfere with microbial metabolites.This topic aims to clarify the efficacy of MgIG in protecting MTX-induced liver injury,and to explore the possible mode of action of MgIG from the perspective of intestinal flora,and to provide new ideas and strategies for the clinical use of MgIG.Research contents and resultsThe research group conducted a preliminary study on the efficacy of MgIG on liver injury induced by various chemotherapeutics.In the study of MgIG on methotrexate-induced acute liver damage in rats,we found that MgIG can not only protect MTX-induced liver damage,but also protect MTX-induced intestinal damage.In this study,C57BL/6 was selected as the research object,and the effect of MgIG on liver damage in mice was evaluated using a MTX-induced liver injury model.Detection of ALT and AST levels in mouse serum by ELISA;calculation of mouse liver organ index;evaluation of liver pathological damage by H&E;Detection of inflammatory factors(IL-6,IL-1?,TNF-?)mRNA levels.It was found that MgIG had a good protective effect on liver injury induced by MTX in mice.In the course of the study,the intestinal function of our MTX liver damage model mice changed,and then we explored the intestinal barrier function of the mice under the MTX liver damage model.HE staining,PAS staining,and dextro-rotation Glycoside leakage experiments were used to evaluate the colonic damage in mice.Elisa was used to detect serum LPS levels in mice and QPCR was used to detect intestinal tight junction protein mRNA levels.It was found that pathological changes in the intestine of mice were also observed in the MTX liver damage model.Based on the close relationship between the liver and the intestine,combined with literature research,we next explored the correlation between MTX-induced liver damage and intestinal toxicity in mice.The liver damage of mice was evaluated by detecting the serum ALT and AST of mice;the intestinal damage of mice was detected by dextran leak test and H&E staining of colon tissue.We found that the intestinal damage of MTX mice was the first to liver damage.Next,we analyzed the effect of MTX on the composition and abundance of intestinal flora of mice by 16sRNA sequencing,and found that administration of MTX would cause disturbance of the intestinal flora of mice and reduce the concentration of SCFAs in the metabolites of the flora.Finally,we explored the pharmacodynamic effects of MgIG on intestinal injury under the MTX liver damage model and its effect on the intestinal flora.H&E staining was used to detect the pathological damage of the mouse colon;PAS staining was used to detect the expression of mouse colon goblet cells.;Detecting intestinal permeability of mice by dextran leak test;Detecting tight junction protein expression in mice colon by Western blot and immunofluorescence It was found that MgIG also had protective effects on intestinal damage induced by MTX.16sRNA sequencing was used to detect the fecal intestinal flora of mice.It was found that MgIG can restore the intestinal flora disturbance induced by MTX and up-regulate the level of SCFAs in the intestine.Conclusion and significanceBased on the above results,we found that 10 mg/kg,20 mg/kg,and 40 mg/kg MgIG could protect MTX-induced liver damage in mice.Under the MTX liver damage model,pathological changes in the intestine of mice,disturbance of intestinal flora,and elevation of LPS in serum indicate that liver damage induced by MTX may be closely related to the "hepatic-gut axis".MgIG can improve the intestinal bacterial abundance and composition disorder of MTX liver damage model mice,reduce the intestinal barrier damage,reduce the intestinal permeability,and lower the serum LPS level.Thus,it exerts a protective effect on liver damage induced by MTX.This study expounded the possible protective mechanism of MgIG protecting MTX-induced liver injury in mice from the perspective of "liver-gut axis",and provided a new reference for the clinical use of MgIG.