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Portulaca oleracea L. (P. oleracea) is an herb that is widely used in traditional medicine to treat various diseases. However, its effects on inflammatory diseases, such as inflammatory bowel disease (IBD), are not yet well characterized. Here, we investigated the impact of the ethyl acetate (EtOAc) and ethanol (EtOH) extracts of P. oleracea on lipopolysaccharide (LPS)-induced inflammatory responses and phosphorylation of ERK, JNK, and p38 expression in RAW264.7 macrophages. In addition, the inhibitory effects of these extracts and fractions on 3% dextran sulphate sodium (DSS)-induced ulcerative colitis were examined using an ICR mouse model. DSS-induced colitis, including body weight loss, reduced colon length, and histological colon injury, was significantly ameliorated in mice fed the P. oleracea extracts (200 and 500mg/kg). In particular, P. oleracea extracts also inhibited pro-inflammatory cytokine (TNF-α, IL-6, and 1L-1β) production in mice with DSS-induced colitis; the P. oleracea extracts displayed higher and/or similar inhibitory activity to sulfasalazine at high concentrations. Furthermore, the chemical structures of active compounds separated from the EtOAc extract of P. oleracea were elucidated using nuclear magnetic resonance (NMR) spectroscopy (see Figure in supplementary materials), resulting in the identification of three known compounds. Among these active compounds, cis-N-feruloyl-3'-methoxytyramine (2) exhibited the strongest effects on preventing DSS-induced IBD in animal models. Thus, extract of P. oleracea and their active compounds represents a new therapeutic approach for patients with inflammatory bowel diseases., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The interleukin-6 (IL-6) family of cytokines plays a key role in the pathogenesis of rheumatoid arthritis and osteoporosis through the regulation of bone formation and resorption. In this study, it was observed that ethanol extract of Salvia plebeia R.Br. (S.P-EE) inhibited IL-6-induced signaling cascade including phosphorylation of JAK2/STAT3 and ERK. Subsequently, it was examined whether S.P-EE treatment could recover bone loss in ovariectomized (OVX) mice. Indeed, S.P-EE exhibited both preventive and therapeutic effect on OVX-induced bone loss in trabecular microarchitecture along with significant increase in bone mineral density and content. To understand the mechanism of action of S.P-EE in bone metabolism, the effect of S.P-EE on osteoclast differentiation and activity was investigated. S.P-EE significantly inhibited RANKL-induced osteoclast differentiation by suppressing phosphorylation of MAPK and Akt, and expression of NFATc1 and osteoclast marker genes. S.P-EE also inhibited bone-resorbing activity of osteoclasts. Furthermore, isolation and identification of the active compounds which are responsible for the inhibitory effect of S.P-EE on osteoclast differentiation was carried out. Six major flavonoids and plebeiolide A-C were isolated and examined their effects on osteoclast differentiation. Luteolin and hispidulin, and plebeiolide A and C, not B exhibited potent inhibitory activity on RANKL-induced osteoclast formation.

Two new feruloyl amides, N-cis-hibiscusamide (5) and (7'S)-N-cis-feruloylnormetanephrine (9), and eight known feruloyl amides were isolated from Portulaca oleracea L. and the geometric conversion of the ten isolated feruloyl amides by UV light was verified. The structures of the feruloyl amides were determined based on spectroscopic data and comparison with literature data. The NMR data revealed that the structures of the isolated compounds showed cis/trans-isomerization under normal laboratory light conditions. Therefore, cis and trans-isomers of feruloyl amides were evaluated for their convertibility and stability by UV light of a wavelength of 254 nm. After 96 h of UV light exposure, 23.2%-35.0% of the cis and trans-isomers were converted to trans-isomers. Long-term stability tests did not show any significant changes. Among all compounds and conversion mixtures collected, compound 6 exhibited the strongest inhibition of IL-6-induced STAT3 activation in Hep3B cells, with an IC50 value of 0.2 μM. This study is the first verification of the conversion rates and an equilibrium ratio of feruloyl amides. These results indicate that this natural material might provide useful information for the treatment of various diseases involving IL-6 and STAT3.

Salvia plebeia R.Br. (SPRB) is a natural resource that exhibits various biological activities. However, its effects on inflammatory diseases are not yet well characterized. This study aimed to evaluate the inhibitory effects of a compound derived from SPRB on interleukin-6 (IL-6)/signal transducer and activator of transcription 3 (STAT3) activation. The chemical structure of active compounds isolated from the EtOAc-soluble fraction of SPRB were elucidated by comparison with spectroscopic nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI–MS) data in the literature, which resulted in the identification of 22 known compounds. All of the isolated compounds were evaluated for potentially higher inhibitory effects on IL-6-induced STAT3 activation in Hep3B cells using a luciferase reporter assay. Furthermore, the protein levels of p-STAT3, p-ERK, and p-JAK2 in IL-6 induced U266 cells were regulated in the presence of cirsimaritin from SPRB by western blot assay. Based on these findings, we suggest that SPRB has the potential to inhibit IL-6-induced STAT3 activation and should be considered in functional food and pharmaceutical applications. [ABSTRACT FROM AUTHOR]