ABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: PLUCHEA INDICA LESS.: (Asteraceae) is a Thai medicinal plant used in traditional medicine for the treatment of hemorrhoids, lumbago, leucorrhoea and inflammation. This study investigated the molecular mechanism of anti-inflammatory activity of Pluchea indica leaf extract in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and also determined its action in acute inflammation animal models. MATERIALS AND METHODS: The inhibitory effect of Pluchea indica leaf extract on LPS-induced nitric oxide (NO) production was evaluated by Griess reaction. Protein and mRNA expressions were determined by real time RT-PCR and Western blotting analysis, respectively. Inducible nitric oxide synthase (iNOS) promoter activity was evaluated by iNOS promoter based reporter gene assay. In vivo anti-inflammatory effect was examined in ethylphenylpropiolate (EPP)-induced ear edema and carrageenan-induced paw edema in rat models. RESULTS: Ethyl acetate fraction of ethanol extract of Pluchea indica leaves (EFPI) exhibited the potent inhibitory effect on NO production in LPS-induced macrophages and also inhibited PGE2 release. EFPI reduced iNOS mRNA and protein expression through suppressed iNOS promoter activity and nuclear translocation of subunit p65 of nuclear factor-κB, but did not inhibit phosphorylation of the mitogen-activated protein kinases (MAPKs). Moreover, EFPI possessed anti-inflammatory activities on acute phase of inflammation as seen in EPP-induced ear edema and carrageenan-induced paw edema inrats. CONCLUSIONS: These data support the pharmacological basis of Pluchea indica plant as a traditional herbal medicine for treatment of inflammation.
Subject(s)
Anti-Inflammatory Agents/therapeutic use , Asteraceae , Edema/drug therapy , Inflammation/drug therapy , Plant Extracts/therapeutic use , Alkynes , Animals , Anti-Inflammatory Agents/pharmacology , Carrageenan , Cell Line , Cell Survival/drug effects , Dinoprostone/metabolism , Disease Models, Animal , Edema/chemically induced , Inflammation/chemically induced , Inflammation/metabolism , Lipopolysaccharides , Macrophages , Male , Mice , Mitogen-Activated Protein Kinases/metabolism , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism , Nitrites/metabolism , Plant Extracts/pharmacology , Plant Leaves , RNA, Messenger/metabolism , Rats , Rats, Sprague-DawleyABSTRACT
AIM OF THE STUDY: Cissus quadrangularis (family: Vitaceae) has been widely used in traditional herbal medicine for the treatment of hemorrhoids, gastric ulcers and bone healing. In the present study, we determined the anti-inflammatory activity and the molecular mechanism of the ethyl acetate extract of Cissus quadrangularis stem (CQE) in LPS-stimulated RAW 264.7 macrophage cells. MATERIALS AND METHODS: The inhibitory effect of CQE on LPS-induced nitric oxide (NO) production was evaluated in conditioned media. Cell viability was monitored by MTT assay. Protein and mRNA expressions were determined by RT-PCR and Western blotting analysis, respectively. RESULTS: CQE potently inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 macrophage cells in a dose-dependent manner. The mRNA and protein expressions of inducible nitric oxide synthase (iNOS) were suppressed also by CQE as was p65 NF-κB nuclear translocation. Further study demonstrated that CQE by itself induced heme oxygenase-1 (HO-1) gene expression at the protein and mRNA levels in dose- and time-dependent manner. In addition, the inhibitory effects of CQE on NO production were abrogated by a HO-1 inhibitor, zinc protoporphyrin IX (ZnPP). CONCLUSIONS: Collectively, these results suggest that CQE exerts an anti-inflammatory effect in macrophages, at least in part, through the induction of HO-1 expression. These findings provide the scientific rationale for anti-inflammatory therapeutic use of Cissus quadrangularis stem.
