Study Of Andrographolide On Alleviation Of Hepatic Sinusoidal Obstruction Syndrome By Based On Nrf2/ARE Signaling Pathway

Hepatic sinusoidal obstruction syndrome(HSOS)is caused by sinusoidal outflow tract obstruction due to sinusoidal endothelial cell injury,which leads to intrahepatic sinus portal hypertension.The main clinical manifestations are ascites,jaundice,hepatomegaly and hepatic pain.Severe cases will be developed into cirrhosis,requiring liver transplantation,and even leads to death.Up to now,there is still no specific drug for the treatment of HSOS.Andrographolide(Andro)is the main active ingredient contained in traditional Chinese medicine Andrographis paniculate,which has anti-inflammatory,liver-protective,anti-viral,anti-tumor and other pharmacological activities.Our presvious study has shown that Andro alleviated liver fibrosis induced by acetaminophen via activating the nuclear factor erythroid 2-related factor 2(Nrf2)-antioxidant response element(ARE)signaling pathway in mouse.However,whether Andro has a therapeutic effect on HSOS has not been reported.In this study,we firstly investigated the protective effects of Andro from MCT-induced HSOS in rats.The HSOS model was induced by 90 mg/kg MCT in rats,and different doses of Andro(50,100 ?g/kg)were administered at 5 h and 29 h after MCT administration.Serum aspartate aminotransferase(AST)and alanine aminotransferase(ALT)activity,protein expression of hepatic matrix metalloproteinase-9(MMP-9),histopathological analysis and scanning electron microscopy evaluation of liver tissues suggest that Andro can alleviate MCT-induced HSOS in rats.Secondly,the determination of the amount of reactive oxygen species(ROS)and malondialdehyde(MDA),and glutathione reductase(GR)activity in liver tissues from rats suggest that Andro can alleviate MCT-induced liver oxidative stress injury.The results of Western blot and Real-time PCR assay showed that Andro itself could induce the nuclear translocation of Nrf2 in liver tissues from rats,and it could also further increase the nuclear translocation of Nrf2 and the expression of its downstream antioxidant enzymes in liver tissues from MCT-treated rats.On the other hand,transmission electron microscopy detection,protein expression of cytochrome C(Cyto C)in liver mitochondria,peroxisome proliferator-activated receptor gamma,coactivator 1 alpha(PGC-1?)and nuclear respiratory factors 1(NRF1)in liver tissues and Real-time PCR results of mitochondrial DNA(mt DNA)suggest that MCT induced mitochondrial damage in liver tissues from rats,while Andro can reverse this damage.Next,it was further observed whether Andro could induce activation of the Nrf2/ARE signaling pathway in HHSEC or L-02.Western blot and Real-time PCR results showed that Andro significantly increased the nuclear translocation of Nrf2 in both HHSECs and L-02 cells,and also increased the expression of Nrf2 downstream antioxidant enzymes.Finally,L-02 cell line overexpressing ARE promoter region binding to luciferase sequence was used to detect the transcriptional activation of Nrf2 by other diterpene lactones in Andrographis paniculata by using luciferase reporter analysis.The experimental results showed that only Andro significantly induced the activation of Nrf2 among these compounds.In summary,Andro alleviated MCT-induced HSOS via attenuating liver oxidative stress injury and promoting mitochondrial biogenesis in livers by activating Nrf2/ARE antioxidant signaling pathway in hepatic sinusoidal endothelial cells and hepatocytes.