AIM: To investigate the signaling pathways implicated in phosphatidylethanolamine (PE)-induced apoptosis of human hepatoma HepG2 cells. METHODS: Inhibitory effects of PE on human hepatoma HepG2 cells were detected by ...AIM: To investigate the signaling pathways implicated in phosphatidylethanolamine (PE)-induced apoptosis of human hepatoma HepG2 cells. METHODS: Inhibitory effects of PE on human hepatoma HepG2 cells were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle, apoptosis and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry. Immunocytochemical assay and Western blotting were used to examine Bcl-2, Bax and caspase-3 protein levels in HepG2 cells treated with PE. RESULTS: PE inhibited the growth of HepG2 cells in a doseand timedependent manner. It did notaffect the cell cycle, but induced apoptosis. PE significantly decreased ΔΨm at 0.25, 0.5 and 1 mmol/L, respectively, suggesting that PE induces cell apoptosis by decreasing the mitochondrial transmembrane potential. The Bcl-2 expression level induced by different concentrations of PE was lower than that in control groups. However, the Bax expression level induced by PE was higher than that in the control group. Meanwhile, PE increased the caspase-3 expression in a doseand time-dependent manner. CONCLUSION: Exogenous PE induces apoptosis of human hepatoma HepG2 cells via the bcl-2/bax pathway.展开更多
目的:探讨石榴花水提物(pomegranate flower water extract,PFW)对2型糖尿病小鼠肝脏胰岛素信号传导的影响及机制。方法:将C57BL/6J随机分为正常组、模型组、二甲双胍组(Met)、石榴花水提物低剂量组(PFWL)和石榴花水提物高剂量组(PFWH)...目的:探讨石榴花水提物(pomegranate flower water extract,PFW)对2型糖尿病小鼠肝脏胰岛素信号传导的影响及机制。方法:将C57BL/6J随机分为正常组、模型组、二甲双胍组(Met)、石榴花水提物低剂量组(PFWL)和石榴花水提物高剂量组(PFWH)。连续给药11周后,称小鼠体质量,检测空腹血糖(FBG)、胰岛素(INS)、甘油三酯(TG)和总胆固醇(TC)的含量,计算胰岛素抵抗指数(HOMA-IR);苏木素-伊红(HE)染色观察肝组织病理变化;Western blot法检测肝组织中胰岛素受体底物1(IRS1)、p-IRS1(Ser307)、蛋白激酶B(AKT)、p-AKT(Ser473)、糖原合成酶激酶-3β(Gsk3β)、p-Gsk3β(S9)、芳香烃受体(AhR)、磷脂酰乙醇胺N-甲基转移酶(PEMT)、Bcl-2/腺病毒E1B-19kDa相互作用蛋白3(BNIP3)蛋白表达。结果:与模型组比较,PFWH组FBG、INS、HOMA-IR、TG和TC含量极显著降低(P<0.01);PFWH组小鼠肝细胞内脂肪滴明显减少;PFWH组极显著升高肝脏中IRS1、p-AKT(Ser473)/AKT、p-Gsk3β(S9)/Gsk3β、BNIP3蛋白表达(P<0.01),极显著降低p-IRS1(Ser307)/IRS1、AHR、PEMT蛋白表达(P<0.01)。结论:PFW可能通过调节AHR/BNIP3抑制肝脏脂质沉积,改善p-IRS1(Ser307)/p-AKT(Ser473)/p-GSK3β(S9)胰岛素信号通路转导。展开更多
AIM: To establish a simple method to quantify lipid classes in liver diseases and to decipher the lipid profile in p62/IMP2-2/IGF2BP2-2 transgenic mice.METHODS: Liver-specific overexpression of the insulin-like growth...AIM: To establish a simple method to quantify lipid classes in liver diseases and to decipher the lipid profile in p62/IMP2-2/IGF2BP2-2 transgenic mice.METHODS: Liver-specific overexpression of the insulin-like growth factor 2 mRNA binding protein p62/IMP2-2/IGF2BP2-2 was used as a model for steatosis.Steatohepatitis was induced by feeding a methioninecholine deficient diet. Steatosis was assessed histologically. For thin layer chromatographic analysis, lipids were extracted from freeze-dried tissues by hexane/2-propanol, dried, redissolved, and chromatographically separated by a two-solvent system. Dilution series of lipid standards were chromatographed, detected, andquantified. The detection was performed by either2',7'-dichlorofluoresceine or a sulfuric acid/ethanol mixture.RESULTS: Histological analyses confirmed steatosis and steatohepatitis development. The extraction,chromatographic, and detection method showed high inter-assay reproducibility and allowed quantification of the different lipid classes. The analyses confirmed an increase of triglycerides and phosphatidylethanolamine and a decrease in phosphatidylcholine in the methionine-choline deficient diet. The method was used for the first time to asses the lipid classes induced in the p62-overexpressing mouse model and showed a significant increase in all detected lipid species with a prominent increase of triglycerides by 2-fold. Interestingly, the ratio of phosphatidylcholine to phosphatidylethanolamine was decreased, as previously suggested as a marker in the progression from steatosis to steatohepatitis.CONCLUSION: The thin layer chromatography analysis allows a reliable quantification of lipid classes and provides detailed insight into the lipogenic effect of p62.展开更多
The gel-liquid crystal phase transitions of the pseudo-binary systems of cephalins DMPE and DHPE in excess water were studied by differential scanning calorimetry. The phase diagram of the pseudebinary systems has bee...The gel-liquid crystal phase transitions of the pseudo-binary systems of cephalins DMPE and DHPE in excess water were studied by differential scanning calorimetry. The phase diagram of the pseudebinary systems has been given. The experiments showed that the partial phase separation in gel phase might occur at least at the mole fractions of DHPE below 0.1. The analysis by the model of ideal solution showed that both the cephalins were non-ideally miscible both in the gel phases and in the liquid crystal phases. The analysis by the model of regular solution showed that all the non-ideality parameters in the gel phases were larger than those in the liquid crystal phases at the same temperature. All the non-ideality parameters were not constant, but rather dependent on temperature.展开更多
基金Supported by The National Natural Science Foundation of China (No. 30872481)the Scientific and Technological Planning Foundation of Shaanxi Province (No. 2006K09-G7-1)
文摘AIM: To investigate the signaling pathways implicated in phosphatidylethanolamine (PE)-induced apoptosis of human hepatoma HepG2 cells. METHODS: Inhibitory effects of PE on human hepatoma HepG2 cells were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle, apoptosis and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry. Immunocytochemical assay and Western blotting were used to examine Bcl-2, Bax and caspase-3 protein levels in HepG2 cells treated with PE. RESULTS: PE inhibited the growth of HepG2 cells in a doseand timedependent manner. It did notaffect the cell cycle, but induced apoptosis. PE significantly decreased ΔΨm at 0.25, 0.5 and 1 mmol/L, respectively, suggesting that PE induces cell apoptosis by decreasing the mitochondrial transmembrane potential. The Bcl-2 expression level induced by different concentrations of PE was lower than that in control groups. However, the Bax expression level induced by PE was higher than that in the control group. Meanwhile, PE increased the caspase-3 expression in a doseand time-dependent manner. CONCLUSION: Exogenous PE induces apoptosis of human hepatoma HepG2 cells via the bcl-2/bax pathway.
文摘目的:探讨石榴花水提物(pomegranate flower water extract,PFW)对2型糖尿病小鼠肝脏胰岛素信号传导的影响及机制。方法:将C57BL/6J随机分为正常组、模型组、二甲双胍组(Met)、石榴花水提物低剂量组(PFWL)和石榴花水提物高剂量组(PFWH)。连续给药11周后,称小鼠体质量,检测空腹血糖(FBG)、胰岛素(INS)、甘油三酯(TG)和总胆固醇(TC)的含量,计算胰岛素抵抗指数(HOMA-IR);苏木素-伊红(HE)染色观察肝组织病理变化;Western blot法检测肝组织中胰岛素受体底物1(IRS1)、p-IRS1(Ser307)、蛋白激酶B(AKT)、p-AKT(Ser473)、糖原合成酶激酶-3β(Gsk3β)、p-Gsk3β(S9)、芳香烃受体(AhR)、磷脂酰乙醇胺N-甲基转移酶(PEMT)、Bcl-2/腺病毒E1B-19kDa相互作用蛋白3(BNIP3)蛋白表达。结果:与模型组比较,PFWH组FBG、INS、HOMA-IR、TG和TC含量极显著降低(P<0.01);PFWH组小鼠肝细胞内脂肪滴明显减少;PFWH组极显著升高肝脏中IRS1、p-AKT(Ser473)/AKT、p-Gsk3β(S9)/Gsk3β、BNIP3蛋白表达(P<0.01),极显著降低p-IRS1(Ser307)/IRS1、AHR、PEMT蛋白表达(P<0.01)。结论:PFW可能通过调节AHR/BNIP3抑制肝脏脂质沉积,改善p-IRS1(Ser307)/p-AKT(Ser473)/p-GSK3β(S9)胰岛素信号通路转导。
基金Supported by The Graduiertenf rderung of Saarland University(Laggai S)an EASL Dame Sheila Sherlock Fellowship(Kessler SM)the research committee of Saarland University(61-cl/Anschub2012)
文摘AIM: To establish a simple method to quantify lipid classes in liver diseases and to decipher the lipid profile in p62/IMP2-2/IGF2BP2-2 transgenic mice.METHODS: Liver-specific overexpression of the insulin-like growth factor 2 mRNA binding protein p62/IMP2-2/IGF2BP2-2 was used as a model for steatosis.Steatohepatitis was induced by feeding a methioninecholine deficient diet. Steatosis was assessed histologically. For thin layer chromatographic analysis, lipids were extracted from freeze-dried tissues by hexane/2-propanol, dried, redissolved, and chromatographically separated by a two-solvent system. Dilution series of lipid standards were chromatographed, detected, andquantified. The detection was performed by either2',7'-dichlorofluoresceine or a sulfuric acid/ethanol mixture.RESULTS: Histological analyses confirmed steatosis and steatohepatitis development. The extraction,chromatographic, and detection method showed high inter-assay reproducibility and allowed quantification of the different lipid classes. The analyses confirmed an increase of triglycerides and phosphatidylethanolamine and a decrease in phosphatidylcholine in the methionine-choline deficient diet. The method was used for the first time to asses the lipid classes induced in the p62-overexpressing mouse model and showed a significant increase in all detected lipid species with a prominent increase of triglycerides by 2-fold. Interestingly, the ratio of phosphatidylcholine to phosphatidylethanolamine was decreased, as previously suggested as a marker in the progression from steatosis to steatohepatitis.CONCLUSION: The thin layer chromatography analysis allows a reliable quantification of lipid classes and provides detailed insight into the lipogenic effect of p62.
基金Project supported by the National Natural Science Foundation of China (Grant No. 29573097)
文摘The gel-liquid crystal phase transitions of the pseudo-binary systems of cephalins DMPE and DHPE in excess water were studied by differential scanning calorimetry. The phase diagram of the pseudebinary systems has been given. The experiments showed that the partial phase separation in gel phase might occur at least at the mole fractions of DHPE below 0.1. The analysis by the model of ideal solution showed that both the cephalins were non-ideally miscible both in the gel phases and in the liquid crystal phases. The analysis by the model of regular solution showed that all the non-ideality parameters in the gel phases were larger than those in the liquid crystal phases at the same temperature. All the non-ideality parameters were not constant, but rather dependent on temperature.
