Glycoside constituents from Miliusa sinensis leaves and their anti-inflammatory and acetylcholine protective effects

Abstract

Repeated column chromatography resulted in the isolation of two new glycosides, miliusides A-B (1 and 7), along with six known metabolites (2-6, and 8) from the leaves of Miliusa sinensis Finet and Gagnep. The structures of the purified phytochemicals were elucidated by interpreting their spectroscopic data (NMR, HRMS), as well as comparison with the previous literature. The biological evaluation of acetylcholinesterase (AChE) inhibitory effects and anti-inflammatory activity by measuring nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 mouse macrophage cells, were also conducted. Among them, compounds 5 and 7 exhibited significant AChE inhibitory activities (IC₅₀ = 53.36 ± 4.20 and 88.50 ± 8.79 µM, respectively), compared with the positive control (Galanthamine, IC₅₀ = 1.65 ± 0.15 µM). Only the MeOH extract showed suppression effects on NO production in LPS-induced RAW264.7 cells (IC₅₀ = 38.18 ± 3.25 μg/mL) comparable to that of the positive control, l-NMMA (IC₅₀ = 2.21 ± 0.56 μg/mL).

Keywords: Annonaceae; Miliusa sinensis; acetylcholinesterase inhibitory; anti-inflammatory activity; glycoside; miliusides A-B.