Studies Of EpCAM Deletion-induced Hepatointestinal Diseases And The Mechanism Of Dihydroartemisinin In Improving Inflammatory Bowel Diseases

Background:Inflammatory bowel disease(IBD)is considered to be a chronic intestinal inflammatory disease that interacts with the environment,mainly including Crohn's disease(CD)and ulcerative colitis(UC),which is clinically characterized as severe diarrhea.Abdominal pain,and even bloody stools may occur.The integrity of the intestinal epithelial tissue is maintained by cell junctions between epithelial cells,including tight junctions,adhesive junctions,gap junctions,desmosome connections,and the like.Intestinal epithelial tissue integrity is impaired when IBD occurs.The intestine is the largest mucosal immunity site in the body.Natural immunity,as the first line of defense,plays an important role in the homeostasis of the intestine.An in-depth understanding of the integrity of the gut and its steady-state equilibrium mechanism is necessary for the development of human health.Studies have shown that it is easier to form a dextran sulfate sodium(DSS)-induced IBD mouse model after knocking down EpCAM in the mouse colon,but thespecific molecular mechanism is still not completely clear.The liver and intestinal epithelium are derived from the same embryonic layer during embryonic development and are an accessory gland of the intestine.During embryonic development,there is a large amount of EpCAM gene expression in hepatocytes.When the mouse is born,the expression of EpCAM gene in the liver cells is decreased or even disappeared,and the expression of EpCAM gene is increased when the hepatocytes become cancerous,but the function of EpCAM gene in liver development and carcinogenesis is still not clear.Therefore,it is important to investigate the effect of EpCAM gene deletion on liver development.Dihydroartemisinin,a derivative of artemisinin,an antimalarial drug,is clinically capable of rapidly controlling the onset and symptoms of malaria.In addition to anti-malarial effects,there are also features such as treatment of lupus erythematosus,inhibition of angiogenesis,neuroprotection,and anti-inflammatory.Therefore,it is necessary to explore its application in the prevention and treatment of other diseases.Objective:1.This study investigated the regulation mechanism of EpCAM gene on intestinal and liver development by analyzing the EpCAM gene targeting mouse model.2.To investigate the relationship between EpCAM gene deletion and IBD by analyzing the EpCAM gene targeting mouse model;3.To establish an IBD model induced by sodium dextran sulfate(DSS)to explore the improvement effect and molecular mechanism of dihydroartemisinin on IBD.Method:1.In vivo,using the EpCAM gene targeting mouse established by CRISPR-Cas9 technology as a model to explore the relationship between the loss of epithelial cell junction molecule(EpCAM)function and IBD;2.To investigate the effect of epithelial cell junction molecule(EpCAM)loss on the junctional structure of mouse intestinal epithelial cells;3.To explore the loss of function of epithelial cell junction molecule(EpCAM),which has an impact on mouse epigenetics;4.Using Caco-2 cells that knock down the EpCAM gene by RNA interference technology as a model to verify whether the results in vitro and in vivo are consistent,and thus confirm whether the changes in the body are regulated by cellular autonomy.5.C57/BL male mice were induced into IBD model mice by dextran sulfate sodium(DSS),and were freely divided into normal group,DSS model group and dihydroartemisinin administration group.In order to induce the establishment of the IBD model(mainly the colitis model),the sodium dextran sulfate(DSS)group and the dihydroartemisinin dose group were given free drinking of sodium dextran sulfate(DSS)for one week,and thenreplaced with pure drinking pure.After 5 days of water,the intestines of the mice were stimulated again with DSS for 6 days,and the mice in the dihydroartemisinin dose group were treated with dihydroartemisinin.Result:1.EpCAM gene deletion causes intestinal inflammation,while EpCAM gene expression is decreased in IBD mice,suggesting that EpCAM gene deletion can be regarded as a genetic factor of IBD;2.EpCAM gene deletion causes changes in tight junction molecules in intestinal epithelial cells;3.EpCAM gene deletion,hepatic glycogen changes may affect liver development by regulating liver glycogen metabolism,liver circRNA;4.Compared with DSS model mice,DHA can alleviate the inflammation of IBD and improve the effect of IBD on the connecting molecules.Conclusion: EpCAM gene deletion affects cell junction molecules,especially tight junction molecules;it may also affect liver development by regulating liver glycogen metabolism and liver circRNA;DHA can alleviate inflammation caused by IBD and its effects on connective molecules.