The Critical Role And Mechanism Of BMP9 In Liver Disease

Objectives Liver fibrosis is a chronic process of wound healing caused by chronic injury,which can lead to portal hypertension,cirrhosis and even liver cancer.it is particularly important to study the mechanism of liver fibrosis progression and find new diagnostic and therapy markers of liver fibrosis.In this study,we aim to explore the mechanism that how BMP9 regulate hepatic fibrosis.What's more,we will further prove BMP9 to be a potential diagnostic marker and therapeutic target for liver fibrosis.Materials and methods1.The relationship between BMP9 concentration and liver fibrosis progression was detected by enzyme-linked immunosorbent assay(ELISA)in the serum of patients with liver fibrosis.2.Construction of two mouse liver fibrosis model: Bile duct Ligation(BDL)liver fibrosis model,CCL4 induced liver fibrosis model.Detection of serum BMP9 concentration in these two liver fibrosis models.3.Exploring the role of BMP9 in liver fibrosis by using several methods:adenovirus-mediated BMP9-sh RNA,BMP9 neutralizing antibodies,BMP9 knockout mouse model.4.The mechanism of how BMP9 promote liver fibrosis was explored by human stellate cell line LX2 and mouse primary mouse hepatic stellate cell.Results1.Serum BMP9 concentration is positively correlated with liver fibrosis grade.What's more,BMP9 concentration is also positively correlated with hyaluronic acid(HA),a liver fibrosis marker.2.BMP9 is overexpressed in BDL and CCL4-induced liver fibrosis mouse model.3.Adenovirus BMP9-sh RNA,BMP9 neutralizing antibody,BMP9 knockout mice can attenuate the progression of CCL4-induced liver fibrosis.4.BMP9 activates hepatic stellate cells via the smad1/5 phosphorylation signaling pathway,thereby affecting the progression of liver fibrosis.K02288,an ALK receptor inhibitor,was selected to block BMP9 signaling.The results showed that K02288 can inhibit BMP9 induced HSC activation.Objectives NAFLD is a liver disease with a high incidence in worldwide.The main cause of NAFLD is steatosis and fat accumulation in the liver.After an well study of the role and mechanism of BMP9 in hepatic fibrosis,our team found that BMP9 knockout mice developed fatty liver and obesity phenotypes in 3-4 month after birth.This research aimed to study the role of BMP9 in fatty liver and the mechanism that how BMP9 regulate NAFLD.Materials and methods 1.Record the changes in body weight and NAFLD phenotype in BMP9 knockout mice.2.The study the role of BMP9 in the development of NAFLD through insulin resistance test,glucose tolerance test and high-fat diet experiments.3.Perform Genome microarray in liver tissue in BMP9 knockout and widetype mice.Screening the key genes and signaling pathways in the process of NAFLD.4.To verify the target genes and signaling pathway of BMP9 in the development of NAFLD.Results 1.The weight of BMP9 knockout mice was significantly higher than that of wide-type mice in the same age.What's more,BMP9 knockout mice develop NAFLD phenotype in 3-4 months after birth.2.BMP9 knockout mice showed insulin resistance and glucose tolerance at 8 weeks old.In the high-fat diet induction experiments,the concentration of BMP9 was significantly reduced in high-fat diet induced mice.3.The genome microarray analysis of liver in BMP9 knockout and widetype mice,It indicate that PPAR signaling pathway and related genes were downregulated in BMP9 knockout mice.