The anti-inflammatory effect of Portulaca oleracea 70% EtOH Extracts on lipopolysaccharide-induced inflammatory response in RAW 264.7 cells

Abstract

Objectives : Portulaca oleracea (PO) have been used as a traditional medicine to treat inflammatory diseases in Korea. However, the anti-inflammatory effect of PO ethanol extract on lipopolysaccharide (LPS)-induced inflammation is not well-known. Therefore, this study was performed to identify the anti-inflammatory effect of PO on LPS induced inflammatory. Methods : Identification of PO was conducted by comparison with purified standards by HPLC. To measure out the cytotoxicity of PO, author performed the MTT assay. To eval uate the anti-inflammatory effects of PO, author examined the inflammatory mediators such as nitric oxide (NO) and pro-inflammatory cytokines (tumor necrosis factor (TNF)-α , interleukin, (IL)-1β and IL-6) on RAW 264.7 cells. Author also examined molecular mechanisms such as mitogen-activated protein kinases (MAPKs) and nuclear factor-B (NF-κ B) activation by western blot. Results : Three major components (peaks 1, 2, 3) were detected in both varieties and peak 1 was characterized as caffeic acid, peak 2 as p-coumaric acid, and peak 3 as ferul ic acid by comparison of chromatographic properties with authentic standards. Extract from PO itself did not have any cytotoxic effect in RAW 264.7 cells. PO inhibited LPS-induced productions of infl ammatory mediators such as NO and pro-inflammatory cytokines in RAW 264.7cells. In addition, PO inhibited the phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2), c-Jun NH2-terminal kinase (JNK) and NF-κ B activation in RAW 264.7 cells. Conclusions : Above experiment data can be an important indicator for the id entification of PO and this study suggest that treatment of PO could reduce the LPS-induced infla mmation. Thereby, PO could be used as a protective agent against inflammation.