Protective Effects And Mechanisms Of Zhenjiang Aromatic Vinegar Extract On Chronic Alcoholic Liver

Zhenjiang aromatic vinegar(ZAV)is a Chinese vinegar,which is produced through solid-state fermentation.It not only has a unique taste,but also is rich in antioxidants.However,the protective effect of ZAV extract on chronic alcoholic liver and the effect on gut microbiota are not clear.Therefore,it is of great significance to study the protective effect and mechanism of antioxidants on chronic alcoholic liver injury.In this study,ZAV of different aging years were taken as the research object,the antioxidants and antioxidant activities in vitro were analyzed.The protective effects of ZAV extract on chronic alcoholic liver injury mice was explored,and the effect of gut microbiota was further elucidated in vivo.Firstly,the total phenolic and total flavonoid contents of ZAV extract detected by Folin-Ciocalteu method and colorimetric method,and the results showed the total phenolic and total flavonoid contents of ZAV extract at aging 10 years(ZAVE)were increased with the aging time.The total phenolic and total flavonoid contents reached highest levels(2.431± 0.026 mg GAE/mL and 2.036 ± 0.046 mg RE/mL,repectively).The main phenolic compounds and content variation in ZAV extract were detected by HPLC.the results showed that 11 kind of phenolic compounds were detected,and the content increased with the aging years.The highest content was 206.34±10.56 mg/L.The antioxidant activities of ZAV extract was evaluated by DPPH,ABTS and FRAP assays.The result showed that the antioxidant activities of ZAV extract showed the increased trend with the aging time.Furthermore,based on the above results,the ZAVE was used as the experimental object of mice.A model of chronic alcoholic liver injury was established to further investigate the protective effects of ZAVE against alcoholic liver injury in vivo.It was found that ZAVE ameliorated alcohol-induced histological changes by HE staining and oil red O staining,especially 750 mg/kg b.w.ZAVE.750 mg/kg b.w.ZAVE reduced the activity of liver enzymes(AST and ALT)and the content of blood lipid(TG and TC)in serum and liver.The ELISA test results shown that 750 mg/kg b.w.ZAVE reduced the production of ROS,MDA,4-HNE and 8-OHdG in the ethanol-induced liver injury mice.Meanwhile,the activities of SOD,CAT and GSH-Px and the level of GSH were significantly increased by ZAVE pretreatment.Moreover,ZAVE prevented alcohol-induced inflammation by suppressing LPS level,activiting iNOS and decreasing the production of pro-inflammatory cytokines(TNF-α,IL-1β and IL-6)and increasing the production of anti-inflammatory cytokines(IL-10),In addition,16S rRNA sequencing of cecal contents in mice with chronic alcoholic liver injury was analysis.The results shown that ZAVE modulated gut microbiota composition and restored gut microbiota homeostasis.In conclusion,ZAV extract is rich in antioxidants,and the activity of ZAV extract was high.ZAV extract prevent chronic ethanol-induced liver injury by improving the liver pathological tissue,reducing the activity of liver enzymes and the content of blood lipids.In addition,ZAVE reversed depletion of oxidative and antioxidative defense system,reduced inflammation and restored gut microbiota homeostasis to alleviate chronic ethanol-induced liver injury in alcohol-treated mice.