Hepatoprotective benzofurans and furanolignans from Gymnema tingens

Coumarins from Sarcandra glabra (Thunb.) Nakai and Acetylcholinesterase Inhibiting Activity

Nine coumarins including a pair of new enantiomers ( 1a / 1b ) and seven known compounds ( 2-8 ) were isolated from Sarcandra glabra (Thunb.) Nakai. Among them, compounds 1a and 1b were naturally occurring coumarin-phenylpropanoid conjugate enantiomers. Their structures were identified by NMR and ECD calculations. Compounds 1-8 were tested for acetylcholinesterase (AchE) inhibiting activity. The results of the enzymology experiment showed that compound 3 demonstrated obvious AchE inhibitory activity which showed an IC 50 value of 1.982 ± 0.003 μ M, and the binding sites were predicted by molecular docking.

The neurotrophic and antineuroinflammatory effects of phenylpropanoids from Zanthoxylum nitidum var. tomentosum (Rutaceae)

Three novel lignans (1, 5 and 6) and two novel quinic acids (16 and 17) along with 15 known phenylpropanoids were obtained from the ethanol extract of Zanthoxylum nitidum var. tomentosum (Rutaceae). Their structures were confirmed by comprehensive spectroscopic data (NMR and HRESIMS), and the absolute configurations of all novel compounds were elucidated based on electronic circular dichroism (ECD) spectroscopic data. The production of nitric oxide (NO) in BV-2 microglial cells induced through lipopolysaccharide (LPS) was used to evaluate in vitro anti-neuroinflammatory activity of compounds 1-20. Compound 2, 3, 7 and 16 showed excellent inhibition of LPS-induced NO production. The structure-activity relationships of the isolates were investigated. In addition, the mechanism of action of 2 was elucidated by RT-PCR and Western blotting analysis, which indicated that it reduced neuroinflammatory mainly through NLRP3/caspase1 signaling pathways in LPS-induced BV2 microglial cells.

Phenylpropanoid derivatives from the fruit of Crataegus pinnatifida Bunge and their distinctive effects on human hepatoma cells

Ten undescribed phenylpropanoid derivatives including four pairs of enantiomers and two 8-9' linked neolignans, together with fifteen known ones were isolated from the fruit of Crataegus pinnatifida Bunge. Their structures were established by comprehensive spectroscopic analyses. Enantiomers were separated successfully by chiral chromatographic column and their absolute configurations were determined by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. The in vitro cytotoxicity of the isolates were evaluated against two human hepatocellular carcinoma, HepG2 and Hep3B cells. Among them, (±)-crataegusanoid A, (±)-crataegusanoid B and crataegusanoid F exhibited moderate cytotoxicity. Interestingly, the different absolute configurations of (±)-crataegusanoid A and B demonstrated enantioselective cytotoxicity in HepG2 cells. Further flow cytometry analysis indicated that both (-)-crataegusanoid A and (-)-crataegusanoid B performed more significant effects on cell apoptosis, autophagy, and cell cycle progression compared with their enantiomers (+)-crataegusanoid A and (+)-crataegusanoid B. In addition, the results revealed that these two pairs of enantiomers induced protective autophagy in HepG2 cells.