水飞蓟素通过调控Nrf2抗氧化通路抑制NLRP3炎症小体改善非酒精性脂肪性肝病

Silymarin inhibits NLRP3 inflammasome to improve nonalcoholicfatty liver disease via regulating Nrf2 antioxidant pathway

目的探究水飞蓟素(Silymarin)影响非酒精性脂肪性肝病(NAFLD)病变进展的机制。方法溶剂、(PA+LPS)、(PA+LPS+Silymarin)3种方式干预人肝癌HepG2细胞后,分别用Western blot、qPCR及荧光探针法检测Nrf2、SIRT2、NLRP3以及其下游Casp1 P45、Casp1 P20蛋白的表达水平以及Nrf2、HO-1、NQO-1的细胞mRNA表达水平以及ROS代谢水平的影响。(PA+LPS+siNC)、(PA+LPS+Silymarin+siNrf2)、(PA+LPS+Silymarin+siNC)、(PA+LPS+siNrf2)四种方式干预HepG2细胞后,再次检测上述蛋白和mRNA等指标。溶剂、HFD和(HFD+Silymarin)3种方式干预小鼠后,对肝脏HE病理切片进行评估,IHC检测肝脏石蜡包埋切片的NLRP3蛋白的组织表达水平的改变。结果 Silymarin可明显升高HepG2细胞的Nrf2和SIRT2表达水平,降低NLRP3、Casp1 P20和ROS表达水平,以及降低小鼠肝脏的NLRP3表达水平。用Nrf2-siRNA特异性抑制Nrf2之后,Silymarin对于NLRP3、Casp1 P20和ROS表达水平的下调受到明显抑制。结论 Silymarin通过调控Nrf2来抑制NLRP3炎症小体而在NASH中发挥抗细胞损伤及抗组织损伤作用。

Aim To investigate the mechanism of Silymarin affecting the progression of nonalcoholic steatohepatitis(NASH).Methods Western blot,qPCR and fluorescence probe were used to detect the expression levels of Nrf2,SIRT2,NLRP3 and Casp1 P45 and Casp1 P20 protein,as well as the expression levels levels of Nrf2,HO-1 and NQO-1 mRNA and ROS metabolism after the intervention of solvent,(PA+LPS)and(PA+LPS+Silymarin).After the intervention to HepG2 cells by four ways,included(PA+LPS+siNC),(PA+LPS+Silymarin+siNrf2),(PA+LPS+Silymarin+siNC),(PA+LPS+siNrf2),the above protein and mRNA and other indices were detected again.After the intervention with solvent,HFD and(HFD+Silymarin),the pathological sections of liver were evaluated,and the changes of tissue expression level of NLRP3 protein in paraffin-embedded sections of liver were detected by IHC.Results Silymarin significantly increased Nrf2 and SIRT2 expression levels in HepG2 cells,decreased NLRP3 and Casp1 P20 and ROS expression levels,and reduced NLRP3 expression levels in mouse liver.After Nrf2-siRNA was used to specifically inhibit Nrf2,Silymarin′s down-regulation of NLRP3 and Casp1 P20 and ROS expression levels was significantly inhibited.Conclusions Silymarin inhibits NLRP3 inflammasome via regulating Nrf2 and plays an anti-cell damage and anti-tissue damage role in NASH.