Liu Zenggen

Anti-inflammatory activity of compounds isolated from Swertia mussotii

Abstract Six compounds were isolated from an ethanol extract of Swertia mussotii and identified as 2-phenylethyl-β-D-glucoside (1), amaroswerin (2), 1,3,7,8-tetrahydroxyxanthone (3), swertiamarine (4), 1,3,8-trihydroxy-5-methoxyxanthone (5) and methylswertianin (6). Compounds 1, 2 and 6 were isolated from S. mussotii for the first time. The anti-inflammatory activities of the compounds were evaluated by determining their effect on the production of NO by LPS-stimulated RAW264.7 cells. Amaroswerin was the most potent inhibitor of NO release, with an IC50 value of 5.42 μg/mL. Treatment with amaroswerin inhibited expression of iNOS at both protein and mRNA levels. Amaroswerin also dose-dependently suppressed production of TNF-α, IL-6 and IL-1β and reduced expression of mRNA for these LPS-stimulated pro-inflammatory mediators. Amaroswerin thus inhibits the expression of iNOS, TNF-α, IL-6 and IL-1β by downregulating transcription in LPS-induced RAW264.7 macrophage cells, indicating that amaroswerin may be a valuable therapeutic agent for the treatment of inflammatory diseases.

Antiproliferative Activity of Phenylpropanoids Isolated from Lagotis brevituba Maxim

The aim of the present study was to evaluate the antiproliferative effect of phenylpropanoids isolated from the n‐BuOH‐soluble fraction of an ethanolic extract of Lagotis brevituba Maxim. The phenylpropanoids were identified as echinacoside, lagotioside, glucopyranosyl(1–6)martynoside, plantamoside, and verbascoside. Three of the compounds, lagotioside, glucopyranosyl(1–6)martynoside, and plantamoside, were isolated from L. brevituba for the first time. The antiproliferative activity of the isolates was evaluated in human gastric carcinoma (MGC‐803), human colorectal carcinoma (HCT116), human hepatocellar carcinoma (HepG2), and human lung cancer (HCT116) cells using an 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. Plantamoside showed promising activity against MGC‐803 cells, with a half maximal inhibitory concentration value of 37.09 μM. The mechanism of the pro‐apoptosis effect of plantamoside was then evaluated in MGC‐803 cells. Changes in cell morphology, including disorganization of the architecture of actin microfilaments and formation of apoptotic bodies, together with cell cycle arrest in G2/M phases, were observed after treatment of plantamoside. The antiproliferative and pro‐apoptotic effects were associated with a decrease in the ratio of Bcl‐2/Bax and reduced mitochondrial membrane potential, which was accompanied by the release of reactive oxygen species and Ca2+ into the cytoplasm. Taken together, the results indicated that plantamoside promotes apoptosis via a mitochondria‐dependent mechanism. Copyright