title: Isolation and characterization of two flavonoids, engeletin and astilbin, from the leaves of Engelhardia roxburghiana and their potential anti-inflammatory properties.
abstract: Engeletin, a flavonoid compound, was isolated from the leaves of Engelhardia roxburghiana for the first time, along with astilbin, another flavonoid. The chemical structures of engeletin and astilbin were confirmed by (1)H and (13)C nuclear magnetic resonance (NMR) and mass spectrometry (MS) spectra, and their anti-inflammatory activities were studied in lipopolysaccharide (LPS)-stimulated mouse J774A.1 macrophage cells. LPS induced the inflammatory state in macrophage cells and increased mRNA expressions of pro-inflammatory cytokines. Engeletin and astilbin exhibited remarkable inhibitory effects on interleukin (IL)-1β and IL-6 mRNA expression. Significant inhibition of LPS-mediated mRNA expressions were also seen in LPS binding toll-like receptor (TLR)-4, pro-inflammatory cytokine tumor necrosis factor (TNF)-α, IL-10, chemoattractant monocyte chemotactic protein (MCP)-1, and cyclooxygenase (COX)-2 genes. The reduced expression of these cytokines may alleviate immune response and reduce inflammatory activation, indicating that engeletin and astilbin may serve as potential anti-inflammatory agents.
authors.affiliation: Department of Nutrition and Food Science, University of Maryland, College Park, Maryland 20742, United States.
authors.forename: Haiqiu
authors.initials: H
authors.lastname: Huang
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Cheng
authors.forename: Haiming
authors.initials: H
authors.lastname: Shi
authors.forename: Wenbo
authors.initials: W
authors.lastname: Xin
authors.forename: Thomas T Y
authors.initials: TT
authors.lastname: Wang
authors.forename: Liangli Lucy
authors.initials: LL
authors.lastname: Yu
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D044948:Flavonols / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D053583:Interleukin-1beta / Q000235:genetics / Q000276:immunology; D029525:Juglandaceae / Q000737:chemistry*; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D051379:Mice; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D051197:Toll-Like Receptor 4 / Q000235:genetics / Q000276:immunology
chemical_list: D000893:Anti-Inflammatory Agents; D044948:Flavonols; D006027:Glycosides; D053583:Interleukin-1beta; D010936:Plant Extracts; D051197:Toll-Like Receptor 4; C522936:engeletin; C099069:astilbin