The Antiinflammation And Antioxidation Mechanism Of Asiatic Acid For Acute Hepatic Injury

Acute Hepatic Injury(AHI)is a rapid loss of liver function-based clinical syndrome caused by a variety of causes,which causes coagulation dysfunction,jaundice,hepatic encephalopathy and multiple organ dysfunction as the main complications,with a very high mortality.Inflammatory response and oxidative stress are the main therapeutic factors of organ damage caused by pathophysiology of multiple liver diseases.Therefore,the study of antioxidant and anti-inflammatory treatment of AHI is a new research strategy.Asiatic acid is a five-ring triterpenoid compound extracted from Centella asiatica,which has the effects of promoting wound healing,anti-inflammatory,anti-microbial,anti-oxidation and anti-tumor and other pharmacological effects.Therefore,the effect and mechanisms of asiatic acid on acute liver injury also requires our further research.In this paper,the anti-inflammatory and anti-oxidative effect and mechanisms of asiatic acid were studied in vitro and in vivo by liver cells and liver injury models.LPS and t-BHP induce inflammation and oxidative stress in the Hep G2 cells,respectively.MTT assay was used to detect the non-toxic concentration of asiatic acid.The anti-inflammatory and anti-oxidative mechanism of asiatic acid were analyzed by ELISA,fluorescence probe,flow cytometry,Western blot and gene editing.LPS/ D-Ga IN-induced acute hepatic injury model was further demonstratedtaht the anti-inflammatory and anti-oxidative effects and mechanism of asiatic acid on LPS/D-Ga IN-induced acute liver injury in vivo.Asiatic acid significantly down-regulated the secretion of TNF-α,IL-6 and IL-β induced by LPS,and also down-regulated the release of t-BHP induced reactive oxygen free radicals in Hep G2 cells,reduces the production of MDA and MPO,increases the expression level of antioxidant enzymes SOD and GSH in Hep G2 cells.In addition,Asiatic acid significantly inhibited t-BHP-induced apoptosis and necrosis of Hep G2 cells.These results indicated that asiatic acid has significant anti-inflammatory and anti-oxidative dual pharmacological effects.The mechanism of anti-inflammatory and anti-oxidation of asiatic acid was also investigated,asiatic acid down-regulated the NF-κB signaling pathway induced by LPS,up-regulated the expression and translocation of Nrf2 protein by activating ERK signal,increased the expression of downstream antioxidant enzyme,played a role in anti-inflammatory and anti-oxidation.Moreover,investigated the Nrf2/ARE signaling pathway in the anti-inflammatory and anti-oxidative effects of Nrf2 / ARE signaling pathway by observing the Nrf2-/-cells,and found that the anti-inflammatory and anti-oxidative effects of asiatic acid were weakened or even disappeared after knockout of the Nrf2 gene.The process of the dual mechanism of action,while the snow oxalic acid in vitro could also inhibit the NF-κB signaling pathway to play an anti-inflammatory effect.The results showed that asiatic acid significantly improved the survival rate of acute liver injury mice in vivo,significantly improved the pathological changes of liver tissue induced by LPS/D-Ga IN in mice,decreased the expression of inflammatory factors(TNF-α,IL-1β,IL-6,etc.),and decreased the levels of ALT/AST in liver tissue and increased the antioxidant activity of liver tissue in mice.Furthermore,the asiatic acid also significantly down-regulated NF-κB signaling pathway and up-regulation of Nrf2/ARE signaling pathway and antioxidant enzyme expression.In conclusion,asiatic acid can play its anti-inflammatory and antioxidant pharmacological activity to treat acute liver injury.