Effect Of Palmitic Acid On The Fatty Degeneration Of Hepatic Cells Induced By Ehanol In Vitro

Objective To establish the model of the suitable concentration of alcohol-induced steatosis in L-02 liver cells according to previous experiments. To explore the effect of different palmitic acid concent-ration on the alcohol-induced lipogenesis and hepatic injury of L-02 liver cells, and to investigate the mechanism involving in it.Method According to the previous experiments the concentr-ation of alcohol we choose for our further experiment was 0.6%, because this concentration not only could establish the model of alcohol-induced steatosis in L-02 liver cells but also had less influence on cell survival rate. The effect of different Palmitic acid concentration(2.5,5,10,20,30,40μmol/L) on the alcohol-induced lipo-genesis of L-02 liver cells survival rate, were detected by MTT assay. The accumulation of lipid droplets were observed by light inverted microscopy after red oil-O staining. An estimation of releasing dose of alanine amino transferase(ALT), aspartate amino transferase(AST) in the culture was detected through automatic biochemical analyzer, and the intracelluer triglyceride(TG) level would be determined by the kit. The Westernblot was used to detect the levels of nuclear SREBP-1c protein in hepatocytes of each group. Result1.When the palmitic acid concentration in the culture was no more than 10μmol/L, the hepatocytes would have higher survival rate than in the Alcohol induced group (P<0.05). When the palmitic acid concentration in the culture was no less than 20μmol/L, the hepatocytes would have lower survival rate than in the alcohol induced group, and the survival rate will decrease as the palmitic acid concentration increasing (P<0.05)2.After incubated in culture with ethanol more than two days, numerous lipiddroplets were gathered in the cytolymph of human L-02 hepatocyte observed by inverted microscopy, which could be dyed to red with red oil-O dying.48h later after different palmitic acid treated:when the palmitic acid concentration was no more than 10μmol/L, lipiddroplets made considerabale reduction,and lipiddrop-lets reduced as the palmitic acid concentration ascending (P<0.05); when the palmitic cid concentration was no less than 20μmol/L, lipiddroplets made different aggratation, and lipiddroplets aggratated as the palmitic acid concentration ascending(P<0.05).3.Compared with the blank control group,the releasing dose of alanine amino transferase(ALT), aspartate amino transferase(AST) in the culture and the intracellular TG levels increased in the 0.6% ethanol groups(P<0.05).48h later after different palmitic acid treated: when the palmitic acid concentration was no more than 10μmol/L these indicators depressed gradually as the palmitic acid concentra-tion ascending(P<0.05); when the palmitic acid concentration was no less than 20μmol/L, these indicators increase,and the releasing dose of ALT, AST depressed as the palmitic acid concentration ascending (P<0.05), but in the 40μmol/L palmitic acid group the intracellular TG level was less than the 20,30μmol/L group(P<0.05).4.Compared with the blank control group, the expression of the levels of nuclear SREBP-lc protein in hepatocytes increased in the 0.6% ethanol groups(P<0.05).48h later after different palmitic acid treated:when the palmitic acid concentration was no more than 10μmol/L, the expression of the levels of nuclear SREBP-lc protein in hepatocytes depressed gradually as the concentration of palmitic acid ascending(P<0.05); when the palmitic acid concentration was no less than 20μmol/L, the expression of the levels of nuclear SREBP-lc protein in hepatocytes increased gradually as the concentration of palmitic acid ascending(P<0.05).Conclusion1.The model of alcohol-induced steatosis in L-02 liver cells can be successfully establashed when the concentration of ethanol is 0.6%, and it also induces the releasing dose of Transaminase releasing.Furthermore alcohol-induced steatosis is related to the upregulation of the expression of nuclear SREBP-lc protein in hepatocytes.2.After the palmitic acid treated,it has therapeutical effect on alcohol-induced steatosis in L-02 liver cells whithin a certain range. On the contrary, it can make the steatosis more serious if the concentration of palmitic acid beyond a certain range.3.The possible mechanisms of the effect of palmitic acid on alcohol-induced steatosis in L-02 liver cells are related to the adjustment of the expression of nuclear SREBP-lc protein in hepatocytes.