OBJECTIVE To investigate the mechanism of SIRT1/AMPK signaling pathway between hepatocytes and hepatic stellate cells(HSCs).METHODS Normal human Chang liver cells and human hepatic stellate cell line,LX-2 cells were t...OBJECTIVE To investigate the mechanism of SIRT1/AMPK signaling pathway between hepatocytes and hepatic stellate cells(HSCs).METHODS Normal human Chang liver cells and human hepatic stellate cell line,LX-2 cells were treated with SRT1720(10μmol·L^(-1))and AICAR(500μmol·L^(-1))prior to ethanol(50 mmol·L^(-1)) for 24 and 48 h.Cell viability was analyzed by methyl thiazolyl tetrazolium assay.SIRT1,AMPK and p-AMPK m RNA levels for 24 h and 48 h were analyzed by RT-PCR,SIRT1,AMPK and p-AMPK protein expressions in the supernatant at 24 and 48 h was detected by Western blot.RESULTS SRT1720 and AICAR effectively decreased LX-2 cell viabilities and exhibited scarcely little toxicity in human Chang liver cells.SRT1720 and AICAR attenuated collagen-I,α-smooth muscle actin(α-SMA)levels,activated liver kinase B-1(LKB1)and AMPK phosphorylation in ethanol treated LX-2 cells.Meanwhile,SRT1720 and AICAR enhanced SIRT1 expression mediated by ethanol both in Chang liver cells and LX-2 cells.Furthermore,SRT1720 and AICAR suppressed the expression of sterol regulatory element-binding protein-1(SREBP-1)to regulate fatty acid synthesis.CONCLUSION SIRT1 agonist and AMPK agonist blocked the crosstalk between hepatocytes and HSCs via SIRT1/AMPK signaling pathway to modulate hepatocytes accumulation of lipid and HSCs activation.展开更多
OBJECTIVE The pathological characteristics of nonalcoholic steatohepatitis(NASH)include liver steatosis,inflammation,and fibrosis.Fibrosis is the most severe and significant pathological feature in NASH.Effective drug...OBJECTIVE The pathological characteristics of nonalcoholic steatohepatitis(NASH)include liver steatosis,inflammation,and fibrosis.Fibrosis is the most severe and significant pathological feature in NASH.Effective drug treatment could reverse early liver fibrosis and is of significance to prevent NASH from progressing into cirrhosis and liver cancer.Identification of drug targets for NASH treatment has been an active research area and is essential for the development of anti-NASH medications.Naringenin(NGN)is a flavonoid compound rich in citrus fruits.Our preliminary data demonstrated that NGN reduced diet-induced lipid accumulation and inflammation in the mouse liver,but whether NGN can attenuate liver fibrosis of NASH is not known.METHODS To study the effect of NGN on NASH fibrosis.WT mice were fed with high fat diet(HFD)and injected intraperitoneally 20%carbon tetrachloride at the same time for 8 weeks to induce NASH,and NGN was administrated by gavage in the meantime.In vitro,LO2 cells and LX2 cells were stimulated by oleic acid(OA)combined with lipopolysaccharide(LPS),respectively.RESULTS Treating the WT mice with NGN 100 mg·kg^(-1)·d-1 significantly attenuated hepatic lipid accumulation,hepatic fibrosis,plasma ALT and AST levels,inhibited protein expression of p-ERK,p-FoxO3a in the mouse livers.In vitro,on OA and LPS stimulated LO2 or LX2 cells,NGN significantly promoted apoptosis of activated hepatic stellate cells while inhibited apoptosis of hepatocytes.Mechanism study indicated that NGN inhibited MAPK pathway and promoted activation of FoxO3a,consequently promoted apoptosis of the activated LX2 cells and inhibited liver fibrosis.CONCLUSION NGN preventes NASH fibrosis via regulating MAPK/FoxO3a pathway,thus promoting apoptosis of the activated hepatic stellate cells.展开更多
基金supported by National Natural Science Foundation of China(81700523)
文摘OBJECTIVE To investigate the mechanism of SIRT1/AMPK signaling pathway between hepatocytes and hepatic stellate cells(HSCs).METHODS Normal human Chang liver cells and human hepatic stellate cell line,LX-2 cells were treated with SRT1720(10μmol·L^(-1))and AICAR(500μmol·L^(-1))prior to ethanol(50 mmol·L^(-1)) for 24 and 48 h.Cell viability was analyzed by methyl thiazolyl tetrazolium assay.SIRT1,AMPK and p-AMPK m RNA levels for 24 h and 48 h were analyzed by RT-PCR,SIRT1,AMPK and p-AMPK protein expressions in the supernatant at 24 and 48 h was detected by Western blot.RESULTS SRT1720 and AICAR effectively decreased LX-2 cell viabilities and exhibited scarcely little toxicity in human Chang liver cells.SRT1720 and AICAR attenuated collagen-I,α-smooth muscle actin(α-SMA)levels,activated liver kinase B-1(LKB1)and AMPK phosphorylation in ethanol treated LX-2 cells.Meanwhile,SRT1720 and AICAR enhanced SIRT1 expression mediated by ethanol both in Chang liver cells and LX-2 cells.Furthermore,SRT1720 and AICAR suppressed the expression of sterol regulatory element-binding protein-1(SREBP-1)to regulate fatty acid synthesis.CONCLUSION SIRT1 agonist and AMPK agonist blocked the crosstalk between hepatocytes and HSCs via SIRT1/AMPK signaling pathway to modulate hepatocytes accumulation of lipid and HSCs activation.
文摘OBJECTIVE The pathological characteristics of nonalcoholic steatohepatitis(NASH)include liver steatosis,inflammation,and fibrosis.Fibrosis is the most severe and significant pathological feature in NASH.Effective drug treatment could reverse early liver fibrosis and is of significance to prevent NASH from progressing into cirrhosis and liver cancer.Identification of drug targets for NASH treatment has been an active research area and is essential for the development of anti-NASH medications.Naringenin(NGN)is a flavonoid compound rich in citrus fruits.Our preliminary data demonstrated that NGN reduced diet-induced lipid accumulation and inflammation in the mouse liver,but whether NGN can attenuate liver fibrosis of NASH is not known.METHODS To study the effect of NGN on NASH fibrosis.WT mice were fed with high fat diet(HFD)and injected intraperitoneally 20%carbon tetrachloride at the same time for 8 weeks to induce NASH,and NGN was administrated by gavage in the meantime.In vitro,LO2 cells and LX2 cells were stimulated by oleic acid(OA)combined with lipopolysaccharide(LPS),respectively.RESULTS Treating the WT mice with NGN 100 mg·kg^(-1)·d-1 significantly attenuated hepatic lipid accumulation,hepatic fibrosis,plasma ALT and AST levels,inhibited protein expression of p-ERK,p-FoxO3a in the mouse livers.In vitro,on OA and LPS stimulated LO2 or LX2 cells,NGN significantly promoted apoptosis of activated hepatic stellate cells while inhibited apoptosis of hepatocytes.Mechanism study indicated that NGN inhibited MAPK pathway and promoted activation of FoxO3a,consequently promoted apoptosis of the activated LX2 cells and inhibited liver fibrosis.CONCLUSION NGN preventes NASH fibrosis via regulating MAPK/FoxO3a pathway,thus promoting apoptosis of the activated hepatic stellate cells.
