Effects Of Panax Notoginseng Saponins On Expression Of LXRα MRNA In Steatotic Hepatocytes LO2

Objective:To study the effects of Panax Notoginseng Saponins(PNS) on expression of LXRαmRNA in steatotic human hepatocytes L02,for further investigating the mechanism of PNS for treating hepatocyte steatosis.Methods:1.A model of steatosis of hepatocytes L02 was established by induction with 50%calf serum after 24 hours,48 hours and 72 hours respectively.The accumulations of lipid droplets in hepatocytes were observed with oil red O staining.The content of TG in hepatocytes,as well as ALT,AST,ALP and LDH in supernatant was measured by automatic biochemical analyzer.2.Avirulent concentrations of PNS on steatotic hepatocytes were performed using MTT assay.The steatotic hepatocytes L02 model was established by inducting with 50%calf serum for 48 hours,sequently divided into 5 groups:normal control group,model group, spontaneous recovery group,low concentration of PNS group(10μg/mL) and high concentration of PNS group(50μg/mL).Meantime,hepatocytes in model group were continuously cultured by 1640 medium contained 50%calf serum while others were cultured by 1640 medium contained 10%calf serum.After 24 hours and 48hours respectively,content of TG in each group was measured by automatic biochemical analyzer,as well as lipid droplets in hepatocytes were detected by oil red O staining.3.The steatotic hepatocytes L02 model was established by induction with 50%calf serum after 48 hours,sequently divided into 5 groups:normal control group,model group, spontaneous recovery group,low concentration of PNS group(10μg/mL) and high concentration of PNS group(50μg/mL).After 24 hours,expression of LXRαmRNA in hepatocytes was examined by RT-PCR.Results:1.Compared with normal control group,content of TG in model group of different time(24h,48h and 72h) were significantly increased(P＜0.01),and lipid droplets in hepatocytes observed by oil red O staining were increase along with the march of time.After 24 hours,levels of ALT and ALP were not changed obviously(P＞0.05),while levels of AST and LDH dramatically increased(P＜0.01).After 48 hours and 72 hours,levels of ALT,AST, ALP and LDH were increased significantly(P＜0.05,P＜0.01).2.Concentrations of PNS which less than 50μg/mL have not significant effect on the steatotic hepatocytes L02 proliferation(P＞0.05).Compared with model group,after cultured with normal medium for 24 hours,content of TG in spontaneous recovery group was significantly declined(P＜0.01),but statistical significance was shown when compared with normal control group(P＜0.01).48 hours later,there is no statistical significance between spontaneous recovery group and normal control group(P＞0.05).Compared with spontaneous recovery group,content of TG in PNS treatment groups for 24 hours significant decreased(P＜0.05),especially in low concentration of PNS group(P＜0.01).But after 48 hours treatment,there is no statistical significance between spontaneous recovery group and PNS treatment groups(P＞0.05).The accumulation of lipid droplets in each group observed by oil red O staining was corresponded to its content of TG.3.Compared with normal control group,expression of LXRαmRNA in model group was significantly up-regulated(P＜0.01).Compared with spontaneous recovery group, expression of LXRαmRNA in PNS treatment groups declined in different levels,especially in low concentration group(P＜0.05).Conclusion:1.A model of steatosis of hepatocytes L02 was established by inducting with 50%calf serum.2.Exposed to normal medium can reverse steatosis of hepatocytes.PNS had direct therapeutic effect on steatotic hepatocytes.3.Expression of LXRαmRNA was close related to the steatosis of hepatocyte.PNS may work by regulating expression of LXRαmRNA.