The hepatitis B virus(HBV) is a global public health challenge due to its highly contagious nature. It is estimated that almost 300 million people live with chronic HBV infection annually. Although nucleoside analogs ...The hepatitis B virus(HBV) is a global public health challenge due to its highly contagious nature. It is estimated that almost 300 million people live with chronic HBV infection annually. Although nucleoside analogs markedly reduce the risk of liver disease progression, the analogs do not fully eradicate the virus. As such, new treatment options and drugs are urgently needed. Psoralen is a nourishing monomer of Chinese herb and is known to inhibit virus replication and inactivate viruses. In this study, we evaluated the potential of psoralen as an anti-HBV agent.Quantitative PCR and Southern blot analysis revealed that psoralen inhibited HBV replication in Hep G2.2.15 cells in a concentration-dependent manner. Moreover, psoralen was also active against the 3TC/ETV-dual-resistant HBV mutant. Further investigations revealed that psoralen suppressed both HBV RNA transcription and core protein expression. The transcription factor FOXO1, a known target for PGC1α co-activation, binds to HBV precore/core promoter enhancer II region and activates HBV RNA transcription. Co-immunoprecipitation showed that psoralen suppressed the expression of FOXO1, thereby decreasing the binding of FOXO1 co-activator PGC1αto the HBV promoter. Overall, our results demonstrate that psoralen suppresses HBV RNA transcription by downregulating the expression of FOXO1 resulting in a reduction of HBV replication.展开更多
文摘目的探讨姜黄素(curcumin)调控沉默信息调节因子1(silent mating-type information regulation 2 homolog1,SIRT1)/叉头盒蛋白O1(forkhead box protein O1,FoxO1)信号通路防控非酒精性脂肪肝(nonalcoholic fatty liver disease,NAFLD)的作用及机制。方法采用脂肪酸诱导HepG2细胞24 h建立NAFLD体外模型,油红O染色后光镜下观察细胞内脂肪变性,透射电镜观察细胞内自噬体形成,比色法检测细胞内总胆固醇(totalcholesterol,TC)、甘油三酯(triglyceride,TG)含量,免疫印迹法检测细胞内沉默信息调节因子1(silent mating type information regulation2 homolog 1,SIRT1)、乙酰化叉头盒蛋白O1(acetylated forkhead box protein O1,AC-FoxO1)、微管相关蛋白1轻链3(microtubule-associated protein 1 light chain 3,LC3)、选择性自噬接头蛋白1(sequestosome 1,SQSTM1/P62)、自噬相关蛋白7(autophagyrelated protein7,ATG7)蛋白质表达,免疫荧光观察细胞内SIRT1和FoxO1蛋白质共定位。结果姜黄素可改善细胞内脂肪变性,自噬体增加,显著降低TC、TG含量及AC-FoxO1、P62蛋白质表达(P<0.01),显著升高SIRT1、ATG7蛋白质表达及LC3-Ⅱ/LC3-Ⅰ比值(P<0.01)。干扰SIRT1表达显著影响了姜黄素对细胞的保护作用及相关蛋白质的调控(P<0.05或P<0.01);姜黄素通过激活SIRT1,增强细胞中FoxO1核定位。干扰SIRT1表达,FoxOl大量迁入细胞质区,SIRT1和FoxOl共定位减少。结论姜黄素通过激活SIRT1促进FoxO1脱乙酰化,诱导自噬,改善肝细胞脂肪变性。
基金supported by the National Science Fund (82104240)Shanghai Science and Technology Innovation Project (20S11906200)self-deployed scientific research projects (State Key Laboratory of Drug Research) (SIMM1903ZZ-03)。
文摘The hepatitis B virus(HBV) is a global public health challenge due to its highly contagious nature. It is estimated that almost 300 million people live with chronic HBV infection annually. Although nucleoside analogs markedly reduce the risk of liver disease progression, the analogs do not fully eradicate the virus. As such, new treatment options and drugs are urgently needed. Psoralen is a nourishing monomer of Chinese herb and is known to inhibit virus replication and inactivate viruses. In this study, we evaluated the potential of psoralen as an anti-HBV agent.Quantitative PCR and Southern blot analysis revealed that psoralen inhibited HBV replication in Hep G2.2.15 cells in a concentration-dependent manner. Moreover, psoralen was also active against the 3TC/ETV-dual-resistant HBV mutant. Further investigations revealed that psoralen suppressed both HBV RNA transcription and core protein expression. The transcription factor FOXO1, a known target for PGC1α co-activation, binds to HBV precore/core promoter enhancer II region and activates HBV RNA transcription. Co-immunoprecipitation showed that psoralen suppressed the expression of FOXO1, thereby decreasing the binding of FOXO1 co-activator PGC1αto the HBV promoter. Overall, our results demonstrate that psoralen suppresses HBV RNA transcription by downregulating the expression of FOXO1 resulting in a reduction of HBV replication.
