The Protectiv Effects And Mechanism Of Antcin H On Acute Liver Injury Induced By APAP Or GalN/TNFα

The drug induced liver injury is one of the most common medicine side effect, and is the fifth cause of death in the world. In China, there were more and more patients suffering from acute liver injury induced by drug. It is well known that acetaminophen (APAP)-induced necrotic liver injury become the leading cause in developed countries especially in US and European countries, and it is also a serious problem in recent decades in China. The liver injury mechanism of Galactosamine(GalN)/TNFa was similar with hepatitis B, cirrhosis and alcohol induced liver injury, and is regarded as typical apoptotic liver injury model. The present research has shown the function of p53 in APAP model. And for the first time we found one main triterpene in Antrodia camphorata, Antcin H, could prevent and cure APAP-induced liver injury either in vivo or in primary mouse hepatocytes. In GalN/TNFa model, Antcin H also show the protective function both in vivo and in vitro. After we detected the protein in whole liver, cytoplasm and mitochondria, measured the ROS level and analyzed the respiration of mitochondria, we concluded that the protection of liver due to the disruption of the interaction between p-JNK and mitochondria. The results are followed:1. p53 plays the protective role in APAP model. The suppression of p53 by antisense oligonucleotide (ASO), PFTa and p53 gene knockout lead to more severe injury after APAP treatment. This given the evidence for the function of p53 in APAP model is protection not harmness. Moreover, p53 activator, Nutlin-3a, could alleviate the liver injury induced by APAP in vivo, which base the theoretical foundation for clinic. More research showed that the protection of liver of p53 was due to downregulation of p-JNK.2. Antcin H pretreatment protected against liver injury in acetaminophen models in mice, either 5 days by oral or 1h i.p. injection. More importantly, Antcin H also offered a significant therapic role against acetaminophen-induced liver injury when it was given one hour after APAP. The protection was verified in primary mouse hepatocytes. Twice pretreatment of Antcin H also prevented the liver injury induced by GalN/TNFa in vivo. Antcin H also prevented the apoptosis induced by Act D/TNFa in primary mouse hepatocytes.3. The mechanism of protection of Antcin H in both APAP and GalN/TNFa was due to discruption of binding between p-JNK and mitochondria. Antcin H significantly inhibited the sustained activation of p-JNK and mitochondrial translocation. After excluding the direct inhibitor of p-JNK and ROS scavenger, we found Antcin H disrupted the binding between p-JNK and mitochondrial outmembrane protein Sab, and reversed the impairment of mitochondrial respiration.