Triterpene Acids from Mesona procumbens Exert Anti-inflammatory Effects on LPS-Stimulated Murine Macrophages by Regulating the MAPK Signaling Pathway

Triterpenoids from Meehania fargesii with Cytotoxic Activity1

In the investigation of Meehania fargesii, eighteen triterpenoids were isolated and identified, including a previously unknown compound with an 13,27-cycloursane skeleton, using techniques like 1D and 2D NMR, and HR-MS. Furthermore, the cytotoxicity of these compounds were evaluated against HCT116, MCF-7, and AGS cell lines using the CCK-8 method to examine their structure-activity relationship. Remarkably, compounds 13 and 16 exhibited higher cytotoxicity across all three cell lines compared to the positive drug. Western blot analysis revealed that these compounds activated apoptosis in HCT116 cells by promoting the Bax protein and inhibiting the Bcl-2 protein. This suggests that compounds 13 and 16 have potential as apoptosis-inducing agents in HCT116 cells.

Anti-inflammatory sesquiterpene and triterpene acids from Mesona procumbens Hemsley

Mesonaprocumbens Hemsley is a plant conventionally processed to provide popular food materials and herbal medicines in Asia. In this study, six triterpene acids, including five new ones (mesonaic acids D-H, 1–5), and one proximadiol-type sesquiterpene (7) were isolated from the methanolic extract of the air-dried M. procumbens. Chemical structures of 1‒7 were established by spectroscopic methods, especially 2D NMR techniques (1H–1H COSY, HSQC, HMBC, and NOESY) and HRESIMS. Concerning their biological activities, compounds 1, 2, 6, and 7 were examined manifesting high inhibition toward the pro-inflammatory NO production with EC50 values ranging from 12.88 to 21.21 µM, outrunning the positive control quercetin (24.12 µM). The mesoeudesmol B (7) identified from M. procumbens is the very first example, which exhibited high anti-inflammatory activity diminishing the level of the lipopolysaccharide-induced NO in RAW264.7 macrophage cells, thereby suppressing the secretion of pro-inflammatory cytokines TNF-α and IL-6 and the level of two critical downstream inflammatory mediators iNOS and COX-2.

Bisabolane-type sesquiterpenes from Vernonia amygdalina: Absolute configuration and anti-inflammatory activity

The phytochemical assessment of Vernonia amygdalina resulted in the isolation and identification of seven undescribed bisabolane-type sesquiterpenes designated amygdanoids A-G and one known analogue. This is the first report of this type of sesquiterpene from V. amygdalina. Their structures, including the absolute configurations, were elucidated by comprehensive analysis with HRESIMS, 1D and 2D NMR, quantum chemical calculations of NMR and electronic circular dichroism (ECD), modified Mosher's method, and the in situ dimolybdenum CD method. The anti-inflammatory activity of the isolates was evaluated. All the isolated compounds clearly inhibited the production of NO and the expression of the iNOS protein. Secretion of the COX-2 protein was constrained by amygdanoids A-F. Further investigation suggested that amygdanoids E exhibited anti-inflammatory activity by suppressing the expression of iNOS and COX-2 as well as the PI3K/AKT/NF-κB signaling pathway.

The Antioxidant and Hypolipidemic Effects of Mesona Chinensis Benth Extracts

In this study, the antioxidant and hypolipidemic effects of Mesona Chinensis Benth (MCB) extracts were evaluated. Seven fractions (F0, F10, F20, F30, F40, F50 and MTF) were obtained from the MCB ethanol extracts. Compared to the commercial antioxidants (vitamin C), MTF and F30 exhibited higher antioxidant activities in the antiradical activity test and the FRAP assay. The half-inhibition concentration (IC50) for MTF and F30 were 5.323 µg/mL and 5.278 µg/mL, respectively. MTF at 200 µg/mL significantly decreased the accumulation of TG in oleic acid (OA)-induced HepG2 cells and reversed the inhibitory effect of Compound C on AMPK (MTF and F30 significantly increased the glucose utilization of insulin-induced HepG2 cells). In addition, the components of MTF were identified by HPLC-MS, which were caffeic acid, quercetin 3-O-galactoside, isoquercetin, astragalin, rosmarinic acid, aromadendrin-3-O-rutinoside, rosmarinic acid-3-O-glucoside and kaempferol-7-O-glucoside. Through statistical correlations by Simca P software, it was found that the main antioxidant and hypolipidemic components of MCB might be caffeic acid, kaempferol-7-O-glucoside, rosmarinic acid-3-O-glucoside and aromadendrin-3-O-rutinoside, which may play important roles in the AMPK pathway. MTF and F30 in MCB could be potential health products for the treatment of hyperlipidemia.

New ent-kaurene and germacrene derivatives from Mesona procumbens Hemseley and their biological activity

Mesona procumbens Hemseley is a well-known traditional herbal medicine used for heat-related ailments. In Taiwan, boiled extracts of M. procumbens are also used as desserts called grass jelly. In this study, the hexane extract from 75% EtOH of M. procumbens showed potent activities on inhibition of E. coli β-glucuronidase (eβG) and NO production and cytotoxicity against MCF-7 and HepG2 cancer cell lines. Furthermore, using various flash columns and HPLC chromatography on the bioactive layer led to the isolation of twelve compounds (1-12), including a new ent-kaurene, mesokaurol A (1), and a new germacrene derivative, mesogermapene A (2). Their structures were elucidated by extensive spectroscopic analyses, especially 2 D NMR and mass data. Biological assays showed that compound 9 (linolenic acid) had specific activity on inhibition of eβG (68.27%) at 100 µg/mL but was non-inhibitory to human β-glucuronidase. Compound 1 possessed significant cytotoxicity against MCF-7 (EC₅₀ = 9.76 µM) and HepG2 (EC₅₀ = 8.64 µM) cancer cell lines.