The Pharmacological Activity Assay Of FXR Antagonist And Mechanism Research Of NSAIDs Induced Liver Injury

Farnesoid X Receptor (FXR), an important ligand-dependent transcription factor, involved in various pathological processes, such as cholecystolithiasis, cholestasis, hypercholesterolemia, hypertriglyceridemia, diabetes, artherosclerosis and so on. Therefore, looking for efficient FXR ligands can provide lead drugs for the treatment of these diseases, which are of great clinical significance. In the present research, we employed structure-based virtual screening combining with yeast two-hybrid, mammalian one-hybrid and transactivation assays to search a novel FXR antagonist1340.1340showed excellent activity against FXR in mRNA and protein levels. Moreover, endoplasmic reticulum stress study indicated that1340could alleviate tunicamycin caused endoplasmic reticulum stress by inhibiting GRP78and CHOP protein levels. Finally, a high-fat diet induced obesity animal experiments found that1340could effectively reduce the content of free fatty acids and cholesterol. Considering novel structure of1340and few reports of nonsteroidal FXR antagonists,1340is expected to become the effective tool in treatment of FXR related diseases.Non-steroidal anti-inflammatory drugs (NSAIDs) cause liver injury which may potentially lead to a fatal outcome or need liver transplantation. However, the molecular mechanisms of NSAIDs-caused liver injury have not been clearly elucidated. There is increasing evidence suggesting that FXR have been considered to play an important role in liver regeneration/repair and inflammatory responses. In the present study, we reported that almost all sorts of NSAIDs except for oxicams and coxibs could be identified as potential FXR antagonists. Moreover, quantitative RT-PCR assay indicated that indomethacin could regulate FXR downstream target genes in HepG2cells. Finally, the functional mechanism investigation of FXR demonstrated that FXR activation relieved indomethacin-induced liver damage by inhibiting signal transducer and activator of transcription3(STAT3) phosphorylation and caspase9activation. These results may demonstrate a novel molecular mechanism that liver injury induced by NSAIDs is mediated through antagonism of FXR. Our work is thus expected to shed light on the molecular mechanism of liver injury and pave the way for further study on liver related diseases.