Reasearch The Relationship Between Uncoupling Protein 2 Expression And Steatosis Of Hepatocytes

Objective:Establish the cell model of hepatocytes steatosis,research the expression of uncoupling protein 2 in normal hepatocytes and fatty liver cells,so as to investigate the effect of UCP2 on liver steatosis and energy metabolism.Methods:Take human liver cell-7702(HL-7702) as research objective. Culture hepatocytes with fatty emulsion,an injection used in clinical as nutritional agents.The cells get steatosis to different degree and make them as the model of fatty liver cells.Regard normal cells as control,and culture the model cells with medium containing variant concentration of fatty emulsion as follows:0.5μl/ml,1.0μl/ml,2.0μl/ml,3.0μl/ml.After being interfered by 48h,72h,and 96h,test cells activity,and AST,ALT in medium and the content of TG,ATP in cells.Paint cells with oil red O, we can observe fatty drops in hepatocytes by microscopy to judge weather the cells have got steatosis.At the same time,we testify the UCP2 mRNA expression by RT-PCR,and utilize western blot technology to verify the UCP2 protein expression.Results:Being interfered within 48 hours,the Aspartate amino-transferase level between normal ones and model groups has no significant difference(p＞0.05),but if we culture cells in fatty emulsion longer time as 72 hours even 96 hours,the AST level increased significantly.We get fatty liver cells by this way successfully.After painting cells,the fatty drops in normal cells are not significant,a lot of fatty drops deposited in cytoplasm appearing as red granular in model ones.There is a positive relationship between the fatty emulsion content and the fatty drops.The TG content in model groups is higher than normal ones(p＜0.01),the ATP content inverse with the degree of fatty steatosis,we verified normal cells contain UCP2 mRNA,and the higher concentration of fatty emulsion,the more UCP2mRNA expression,there is statistics significance(P＜0.01);we get there is no UCP2 protein expression in normal cells,in model cells the UCP2 protein increase in accordance with the concentration of fatty emulsion(P＜0.05).Conclusion:Culture HL-7702 cells with fatty emulsion medium,we can get the cell model of non-alcoholic fatty liver cells.The expression of UCP2 in fatty liver cells is higher than normal ones,and there is a positive relationship between the steatosis of fatty liver cells and the quantity of UCP2.The UCP2 content is in positive relationship with TG, but in negative relationship with ATP.So the UCP2 may have no protective effect on steatosis of hepatocytes.