title: Demethoxycurcumin from Curcuma longa rhizome suppresses iNOS induction in an in vitro inflamed human intestinal mucosa model.
abstract: It is known that inducible nitric oxide synthase (iNOS)/nitric oxide (NO) plays an integral role during intestinal inflammation, an important factor for colon cancer development. Natural compounds from Curcuma longa L. (Zingiberaceae) have long been a potential source of bioactive materials with various beneficial biological functions. Among them, a major active curcuminoid, demethoxycurcumin (DMC) has been shown to possess anti-inflammatory properties in lipopolysaccharide (LPS)-activated macrophages or microglia cells. However, the role of DMC on iNOS expression and NO production in an in vitro inflamed human intestinal mucosa model has not yet been elucidated. This study concerned inhibitory effects on iNOS expression and NO production of DMC in inflamed human intestinal Caco-2 cells. An in vitro model was generated and inhibitory effects on NO production of DMC at 65 μM for 24-96 h were assessed by monitoring nitrite levels. Expression of iNOS mRNA and protein was also investigated. DMC significantly decreased NO secretion by 35-41% in our inflamed cell model. Decrease in NO production by DMC was concomitant with down-regulation of iNOS at mRNA and protein levels compared to proinflammatory cytokine cocktail and LPS-treated controls. Mechanism of action of DMC may be partly due to its potent inhibition of the iNOS pathway. Our findings suggest that DMC may have potential as a therapeutic agent against inflammation-related diseases, especially in the gut.
authors.affiliation: School of Allied Health Sciences and Public Health, Walailak University, Nakhon Si Thammarat, Thailand E-mail : cwarang@wu.ac.th.
authors.forename: Mayura
authors.initials: M
authors.lastname: Somchit
authors.forename: Chatchawan
authors.initials: C
authors.lastname: Changtam
authors.forename: Rungruedi
authors.initials: R
authors.lastname: Kimseng
authors.forename: Tanyarath
authors.initials: T
authors.lastname: Utaipan
authors.forename: Monthon
authors.initials: M
authors.lastname: Lertcanawanichakul
authors.forename: Apichart
authors.initials: A
authors.lastname: Suksamrarn
authors.forename: Warangkana
authors.initials: W
authors.lastname: Chunglok
mesh_terms: D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D018938:Caco-2 Cells; D045744:Cell Line, Tumor; D030024:Curcuma / Q000378:metabolism; D003474:Curcumin / Q000031:analogs & derivatives* / Q000494:pharmacology; D036381:Diarylheptanoids; D006801:Humans; D007249:Inflammation / Q000188:drug therapy* / Q000276:immunology; D007413:Intestinal Mucosa / Q000276:immunology / Q000473:pathology*; D008070:Lipopolysaccharides; D009569:Nitric Oxide / Q000096:biosynthesis; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors* / Q000235:genetics; D028321:Plant Preparations / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis
chemical_list: D000893:Anti-Inflammatory Agents; D036381:Diarylheptanoids; D008070:Lipopolysaccharides; D028321:Plant Preparations; D012333:RNA, Messenger; D009569:Nitric Oxide; C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II; D003474:Curcumin; C050229:demethoxycurcumin