Résumé
BACKGROUND: Curcumin, a yellow ingredient of turmeric (Curcuma longa Linn, Zingiberaceae), has long been used in traditional folk medicine in the management of inflammatory disorders. Although curcumin has been reported to inhibit experimentally-induced colitis and carcinogenesis, the underlying molecular mechanisms remain largely unresolved. METHODS: Murine colitis was induced by dextran sulfate sodium (DSS) which mimics inflammatory bowel disease. Curcumin or tetrahydrocurcumin was given orally (0.1 or 0.25 mmol/kg body weight daily) for 7 days before and together with DSS administration (3% in tap water). Collected colon tissue was used for histologic and biochemical analyses. RESULTS: Administration of curcumin significantly attenuated the severity of DSS-induced colitis and the activation of NF-κB and STAT3 as well as expression of COX-2 and inducible nitric oxide synthase. In contrast to curcumin, its non-electrophilic analogue, tetrahydrocurcumin has much weaker inhibitory effects. CONCLUSIONS: Intragastric administration of curcumin inhibited the experimentally induced murine colitis, which was associated with inhibition of pro-inflammatory signaling mediated by NF-κB and STAT3.
Sujets)
Animaux , Souris , Poids , Carcinogenèse , Colite , Côlon , Curcuma , Curcumine , Sulfate dextran , Dextrane , Maladies inflammatoires intestinales , Médecine traditionnelle , Nitric oxide synthase type IIRésumé
Objective: To investigate the effects of pectic polysaccharides extracted from Rauwolfia verticillata (Lour.) Baill.var.hainanensis Tsiang on an experimental murine colitis model. Methods: Experimental colitis was induced by dextran sulfate sodium (DSS), and mice were divided into 4 groups: control, DSS alone, DSS plus SASP, DSS plus pectic polysaccharides. The disease activity index (DAI) and histological score were observed. The tumor necrosis factor (TNF)- α and interleukin (IL)-17 levels were measured by enzyme-linked immunosorbent assay. I κ B and NF- κ B p65 expression were assessed by western blot analysis. Myeloperoxidase (MPO) activity was determined by using MPO assay kit. Results: Administration of pectic polysaccharides significantly reduced the severity of DSS-induced colitis as assessed by DAI and histological score, and resulted in down regulation of MPO activity and NF- κ B p65 expression and subsequent degradation of I κ B protein, strikingly reduced the production of TNF- a and IL-17. Conclusions: Pectic polysaccharides extracted from Rauvolfia verticillata (Lour.)Baill.var. hainanensis Tsiang exerts beneficial effects in experimental colitis and may therefore provide a useful therapeutic approach for the treatment of UC.
Résumé
OBJECTIVE@#To investigate the effects of pectic polysaccharides extracted from Rauwolfia verticillata (Lour.) Baill.var.hainanensis Tsiang on an experimental murine colitis model.@*METHODS@#Experimental colitis was induced by dextran sulfate sodium (DSS), and mice were divided into 4 groups: control, DSS alone, DSS plus SASP, DSS plus pectic polysaccharides. The disease activity index (DAI) and histological score were observed. The tumor necrosis factor (TNF)- α and interleukin (IL)-17 levels were measured by enzyme-linked immunosorbent assay. I κ B and NF- κ B p65 expression were assessed by western blot analysis. Myeloperoxidase (MPO) activity was determined by using MPO assay kit.@*RESULTS@#Administration of pectic polysaccharides significantly reduced the severity of DSS-induced colitis as assessed by DAI and histological score, and resulted in down regulation of MPO activity and NF- κ B p65 expression and subsequent degradation of I κ B protein, strikingly reduced the production of TNF- a and IL-17.@*CONCLUSIONS@#Pectic polysaccharides extracted from Rauvolfia verticillata (Lour.)Baill.var. hainanensis Tsiang exerts beneficial effects in experimental colitis and may therefore provide a useful therapeutic approach for the treatment of UC.