Study on the potential hypoglycemic flavonoids in Abrus precatorius leaves: purification process, quality profile and activity mechanisms by transcriptomics and network pharmacology.

The aim of the study was to investigate the relationship between flavonoids in Abrus precatorius leaves (APL) and their hypoglycaemic effects, which have not been studied before. An efficient purification process, transcriptomics and network pharmacology analysis were applied for the first time. High-performance liquid chromatography (HPLC) was used to determine the content of total flavonoids. The results showed that D101 resin was most suitable for purification of flavonoids of APL, which could increase its purity from 25.2% to 85.2% and achieve a recovery rate of 86.9%. The analysis of transcriptomics and network pharmacology revealed that flavonoids of APL could play a hypoglycaemic role by regulating 31 targets through AGE-RAGE and other signal pathways. Flavonoids of APL could exert hydroglycaemic effects by inhibiting AGEs, α-glucosidase and DPPH. This study provides a solid basis for hypoglycaemic product development and in-depth research of flavonoids in APL.

A Comparative Study between Abrus cantoniensis and Abrus mollis: Flavonoids Profiles by UPLC-Q-TOF-MS and Anti-Inflammatory Mechanism by Transcriptomics.

Abrus mollis (MJGC) has been used as a substitute herb for Abrus cantoniensis (JGC) in China. However, an in-depth comparison on their key metabolites and the mechanism of anti-inflammation between these two is not available. In this report, high pressure liquid chromatography equipped with mass spectrometry was applied to capture their flavonoid profiles; transcriptomics was adopted to analyze their anti-inflammatory mechanisms. The results showed that the main flavonoids in MJGC were vicenin-2, schaftoside and isoschaftoside, while those in JGC were vicenin-1 isomer and schaftoside isomer. The anti-inflammatory activity of JGC was slightly stronger than that of MJGC. The number of differential expression genes regulated by JGC was significantly higher than MJGC. JGC regulated 151 (42 up and 109 down) of inflammation related genes, while MJGC regulated 58 (8 up and 50 down) of inflammation related genes. The results of this study provided scientific evidence and guidance for the substitution of MJGC and JGC.

The isolation, structure and fragmentation characteristics of natural truxillic and truxinic acid derivatives in Abrus mollis leaves.

Five undescribed compounds were separated from Abrus mollis leaves, including two truxillate forms (abrusamide D, H) and three truxinate forms (abrusamide E, F, G). The absolute configuration of abrusamide D was determined by X-ray crystallography. Abrusamide A was reassessed and corrected to be ß-truxinate configuration rather than α-form. LC-MS/MS and CD spectroscopy were applied to determine and analyze ten compounds, including four truxillate forms (abrusamide B ~ D and H), four truxinate forms (abrusamide E ~ G and A), and two precursors [(E)-N-(4-hydroxycinnamoyl) tyrosine, (Z)-N-(4-hydroxycinnamoyl) tyrosine]. It showed that the fragmentation pattern of truxillate was symmetric, while that of truxinate was asymmetric and irregular. The CD Cotton effect was related to cyclobutane configuration. These findings provided strong evidence for the cyclobutane dimers to discriminate their configuration. In addition, the bioactivity assay showed that the compounds had low toxicity and anti-inflammatory effect.