yangonin and Chemical-and-Drug-Induced-Liver-Injury

Hepatic fibrosis is a reversible would-healing response following chronic liver injury of different aetiologies and represents a major worldwide health problem. Up to date, there is no satisfactory drugs treated for liver fibrosis. The present study was to investigate hepatoprotection of yangonin against liver fibrosis induced by thioacetamide (TAA) in mice and further to clarify the involvement of farnesoid X receptor (FXR) in vivo and in vitro. Yangonin treatment remarkably ameliorated TAA-induced liver injury by reducing relative liver weight, as well as serum ALT and AST activities. Moreover, yangonin alleviated TAA-induced accumulation of bile acids through increasing the expression of bile acid efflux transporters such as Bsep and Mrp2, and reducing hepatic uptake transporter Ntcp expression, all of these are FXR-target genes. The liver sections stained by H&E indicated that the histopathological change induced by TAA was improved by yangonin. Masson and Sirius red staining indicated the obvious anti-fibrotic effect of yangonin. The mechanism of anti-fibrotic effect of yangonin was that yangonin reduced collagen content by regulating the genes involved in hepatic fibrosis including COL1-α1 and TIMP-1. Besides, yangonin inhibited hepatic stellate cell activation by reducing TGF-β1 and α-SMA expression. In addition, yangonin protected against TAA-induced hepatic inflammation via its inhibition of NF-κB and TNF-α. These hepatoprotective effects of yangonin were abrogated by guggulsterone which is a FXR antagonist. In vitro experiment further demonstrated dose-dependent activation of FXR by yangonin using dual-luciferase reporter assay. In summary, yangonin produces hepatoprotection against TAA-induced liver fibrosis via FXR activation.

Topics: Animals; Chemical and Drug Induced Liver Injury; Cytokines; Hep G2 Cells; Humans; Liver; Liver Cirrhosis; Male; Mice, Inbred C57BL; Pregnenediones; Protective Agents; Pyrones; Receptors, Cytoplasmic and Nuclear; Thioacetamide

Cholestasis is a clinical syndrome with systemic and intrahepatic accumulation of excessive toxic bile acids that ultimately cause hepatobiliary injury. Recently obeticholic acid (OCA) which is a farnesoid X receptor (FXR) agonist was approved by FDA to treat cholestatic liver diseases, which provided us a newly therapeutic strategy against cholestasis. The purpose of the current study is to screen novel FXR agonists and verify the anti-cholestasis effect of yangonin in vivo and in vitro. The computational strategy of two-dimensional virtual screening was used to search for new FXR agonists, and dual-luciferase reporter gene assay was used to further demonstrate FXR activation by yangonin. Then, the hepatoprotective effect of yangonin via FXR activation against cholestasis and hepatotoxity was evaluated in mice and was investigated using FXR silence in cells. Yangonin was found to activate FXR to exert hepatoprotective effect against cholestatic liver injury. Dynamic change analysis of bile acids and gene analysis revealed that yangonin promoted bile acid efflux into bile and reduced hepatic uptake via the regulation of FXR-target genes Bsep, Mrp2 and Ntcp expression. Furthermore, yangonin modulated enzymes involved in bile acid synthesis and metabolism including Cyp7a1 Cyp8b1 and Sult2a1. In addition, yangonin promoted liver repair and suppressed liver inflammation. However, the changes in these genes and protein, as well as ameliorative liver histology induced by yangonin were abrogated by FXR antagonist guggulsterone in vivo and FXR siRNA in vitro. Yangonin produces protective effect against cholestasis via FXR activation. Yangonin may be an effective approach for the prevention and treatment for cholestatic liver diseases.

Topics: Animals; Bile Acids and Salts; Chemical and Drug Induced Liver Injury; Cholestasis; Cytoprotection; Disease Models, Animal; Dose-Response Relationship, Drug; Gene Expression Regulation; Hep G2 Cells; Humans; Ligands; Liver; Liver Regeneration; Male; Mice, Inbred C57BL; Molecular Docking Simulation; Molecular Structure; Protective Agents; Pyrones; Receptors, Cytoplasmic and Nuclear; RNA Interference; Signal Transduction; Structure-Activity Relationship

In recent years, Kava kava (Piper methysticum, Forst. f., Piperaceae), a folkloric beverage and popular herbal remedy, has been implicated in a number of liver failure cases. Many hypotheses as to the mechanism of its hepatotoxicity, for example interactions with other co-ingested medication, have been postulated. This present study investigated whether pharmacokinetic interactions between kava constituents and alcohol via alcohol dehydrogenase (ADH) inhibition by individual kavalactones might explain its claimed hepatotoxic effects. Four kavalactones, (+/-)-kavain, methysticin, yangonin and desmethoxyyangonin, fail to inhibit ADH in vitro at 1, 10 or 100 microM concentrations.

Topics: Alcohol Dehydrogenase; Alcohol Drinking; Chemical and Drug Induced Liver Injury; Herb-Drug Interactions; Kava; Lactones; Plant Extracts; Pyrans; Pyrazoles; Pyrones; Spectrophotometry