Ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry-based plasma metabolomics study of hepatoprotective effect of cuscutae semen on CCl4 -induced liver injury model of rats.

Hepatic disorders are a serious health problem threatening human beings. Cuscutae semen (CS), a widely used Chinese medicine, is a tonic to nourish the liver and kidney. Our research aimed to assess the hepatoprotective effect of CS on CCl4 -induced liver injury rats using plasma metabolomics. Liver injury in rats was induced by 40% CCl4 in olive oil twice a week for 21 days. The CS group received 2 g/kg of CS every day for 21 days. The liver tissues were used for histological studies. The serum was used for the analysis of biochemical parameters. Plasma metabolomic analysis was performed using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. CS could relieve hepatocyte necrosis and decrease the levels of serum biochemical parameters in comparison the with CCl4 group. Principal component analysis and orthogonal partial least squares-discriminant analysis on plasma metabolomes showed an obvious separation among the control, model, and CS groups. Heatmap showed that CS-administered mice had similar metabolite profiles as the control group. Seven influential pathways in plasma of the hepatoprotective effect impacted by CS were identified. This study confirmed the hepatoprotective effect of CS, and the related metabolic pathways were discussed.

[Identification of 3-demethylchuangxinmycin from Actinoplanes tsinanensis CPCC 200056].

Chuangxinmycin (CM) from Actinoplanes tsinanensis was an antibiotic discovered by Chinese scientists about 40 years ago. It contains a new heterocyclic system of indole fused with dihydrothiopyran, whose biosynthetic mechanism remains unclear. CM is used as an oral medicine in the treatment of bacterial infections in China. The simple structure makes CM as an attractive candidate of structure modification for improvement of antibacterial activity. Recently, we analyzed the secondary metabolites of Actinoplanes tsinanensis CPCC 200056, a CM producing strain, as a natural CM analogue. We discovered the first natural CM analogue 3-demethylchuangxinmycin (DCM) as a new natural product. Compared to CM, DCM exhibited a much weaker activity in the inhibition of the bacterial strains tested. The finding provides valuable information for the structure-activity relationship in the biosynthesis of CM.