Abrus mollis is a widely used traditional Chinese medicine for treating acute and chronic hepatitis, steatosis, and fibrosis. It was found that the total flavonoid C-glycosides from Abrus mollis extract(AME) showed potent antioxidant, anti-inflammatory, and hepatoprotective activities. To further investigate the hepatoprotective effect of AME and its possible mechanisms, lipopolysaccharide(LPS)-induced liver injury models were applied in the current study. The results indicated that AME significantly attenuated LPS-induced lipid accumulation in mouse primary hepatocytes as measured by triglyceride(TG) and total cholesterol(TC) assays and Oil Red O staining. Meanwhile, AME exerted a protective effect on LPS-induced liver injury as shown by decreased liver index, serum aminotransferase levels, and hepatic lipid accumulation. Real-time PCR and immunoblot data suggested that AME reversed the LPS-mediated lipid metabolism gene expression, such as sterol regulatory element-binding protein-1(SREBP-1), fatty acid synthase(FAS), and acetyl-CoA carboxylase 1(ACC1). In addition, LPS-induced overexpression of activating transcription factor 4(ATF4), X-box-binding protein-1(XBP-1), and C/EBP homologous protein(CHOP) were dramatically reversed by AME. Furthermore, AME also decreased the expression of LPS-enhanced interleukin-6(IL-6) and cyclooxygenase-2(COX-2). Here, it is demonstrated for the first time that AME ameliorated LPS-induced hepatic lipid accumulation and that this effect of AME can be attributed to its modulation of hepatic de novo fatty acid synthesis. This study also suggested that the hepatoprotective effect of AME may be related to its down-regulation of unfolded protein response(UPR) activation.
Dihydrotetrabenazine(DTBZ) is the major pharmacologically active form of tetrabenazine(TBZ),which was approved by FDA for the treatment of chorea associated with Huntington’s disease(HD).An unexpected Hoffmann elimination was observed during the treatment of DTBZ with sodium hydrogen and alkyl halides,leading to the formation of both eliminated products(major) and hydroxyl-alkylated products(minor).
Zhang Yu YaoHao ZhangHuan Ming ShengXiao Ming WuHong Bin Sun
The present study was designed to investigate the effects of start codon of nosM on the biosynthesis of nosiheptide. Target genes were amplified by overlap PCR. After homologous recombination to construct engineered strains, nosiheptide production was analyzed by HPLC. Three mutants with different start codon ofnosMwere constructed, and nosihcptide production of each mutant was analyzed and compared. Replacement of the start eodon of nosM significantly decreased the production of nosiheptide. In conclusion, start codon usage could greatly affect the biosynthetic efficiency in the biosynthetic gene cluster of nosiheptide.
