Monascus vinegar alleviates high-fat-diet-induced inflammation in rats by regulating the NF-κB and PI3K/AKT/mTOR pathways

Monascus vinegar(MV) is a typical fermented food with various health-promoting effects. This study aimed to evaluate the role of MV in alleviating high-fat-diet-induced inflammation in rats with hyperlipidemia and elucidate the possible regulatory mechanisms. In the study, serum lipid profiles, liver pathology and liver inflammatory cytokines were analyzed in hyperlipidemia rats with MV(0.5 mL/kg mb, 2 mL/kg mb). Results showed that the administration of MV alleviated dyslipidemia by decreasing the serum and liver levels of triglyceride and total cholesterol. Increase in hepatic lipase and carnitine palmitoyl transferase 1(CPT-1)levels and decrease in hepatocyte steatosis, nephritis, and intestinal tissue injury in the HD group showed that high-dose MV can significantly suppress hepatic lipid accumulation and steatosis. In addition, compared with the model(MOD) group, the HD group showed significantly down-regulated the level of serum or hepatic alanine aminotransferase(ALT), aspartate aminotransferase(AST), CPT-1, interleukin(IL)-2, IL-6, IL-12,and tumor necrosis factor α(TNF-α). Moreover, the HD group showed repressed hepatic nuclear factor κB(NF-κB) pathway and inactivated phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) pathway mitigated liver inflammation. Similar results were obtained from cell experiments. Collectively, these findings revealed that MV might attenuate high-fat-diet-induced inflammation by inhibiting the NF-κB and PI3K/Akt/mTOR pathways.

Metagenomic analysis revealing the metabolic role of microbial communities in the free amino acid biosynthesis of Monascus rice vinegar during fermentation

Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation.