The Effect Of HBx Gene On Mouse Liver Cells Apoptosis And Cycle In Vivo

Objective: To investigate the role of HBx(Hepatitis B virus X)on the apoptosis and cycle of liver cells and its mechanisms in the mice with normal immune,HBx was overexpressed in KM mice.Methods: At first,the expression of EGFP in HPCs(hepatic progenitor cells)was imaged and the expression of HBx in HPCs was detected by qRT-PCR and Western blotting.The animal model was constructed by injecting HBx-EGFP-14-19 cells into the hepatic portal vein of KM mice.The liver tissues of mice were collected 60 days,90 days and 120 days after surgery,and the expression of EGFP in mouse liver was observed;the expression of HBx in the liver was detected by qRT-PCR,Western blotting and immunohistochemistry.Then,the apoptosis index of liver cells was investigated by TUNEL-FITC /DAPI method,and the expressions of apoptosis-related and cycle-related factors were detected by qRT-PCR and Western blotting.Moreover,the expressions of Akt/mTOR signaling factors were detected in HBx-EGFP-14-19 mice with or without Akt inhibitor.Results: The apoptosis index of HBx-EGFP-14-19 liver cells was decreased;the expressions of pro-apoptotic factors caspase-9 and Bad were reduced,and the expression of anti-apoptotic factor Bcl-xl was increased.The mRNA expressions of CDK2,cyclinD1 and cyclinE were increased,and the protein expressions of CDK2,cyclinD1,cyclinE,p-Akt and p-mTOR were increased.Futhermore,the inactivating apoptosis by overexpression HBx was completely abolished by the treatment of Akt inhibitor.Conclusion: HBx reduces liver cells apoptosis and up-regulate the expression of cell cycle regulators in vivo by activating Akt/mTOR signaling pathway.