title: Extracts of Magnoliae flos inhibit inducible nitric oxide synthase via ERK in human respiratory epithelial cells.
abstract: Nitric oxide (NO) is a marker of pulmonary inflammation. In asthma, the levels of exhaled NO are elevated and the source of this increased NO is inducible nitric oxide synthase (iNOS) within airway epithelial cells. Epimagnolin and fargesin are compounds isolated from the ethanol extract of Magnoliae flos, the seed of the Magnolia plant and are used to treat nasal congestion, headache and sinusitis in Asian countries. This study investigated whether epimagnolin and fargesin inhibit extracellular signal-regulated kinase (ERK) activation and decrease iNOS expression and NO production in stimulated human respiratory epithelial cells. An immortal Type II alveolar cell line of human origin (A549) was stimulated by cytomix (CM), composed of IL-1beta, TNF-alpha and IFN-gamma, with or without concurrent exposure to M. flos extract (epimagnolin or fargesin). CM-induced levels of NO production, iNOS expression and ERK activation were evaluated. A549 cells stimulated with CM showed increases in iNOS mRNA and protein expression, and NO synthesis. However, treatment with epimagnolin or fargesin decreased levels of iNOS mRNA and protein expression, and NO synthesis. CM stimulated a rapid increase in the activity of ERK, whereas epimagnolin and fargesin inhibited ERK phosphorylation. Epimagnolin and fargesin inhibit iNOS expression and decrease production of NO via ERK pathway in cytokine-stimulated human respiratory epithelial cells.
authors.affiliation: Department of Internal Medicine, Eulji University School of Medicine, Seo-Gu, Daejeon, Republic of Korea.
authors.forename: Jin Ah
authors.initials: JA
authors.lastname: Baek
authors.forename: Yang Deok
authors.initials: YD
authors.lastname: Lee
authors.forename: Chan Bog
authors.initials: CB
authors.lastname: Lee
authors.forename: Hyeon Kyu
authors.initials: HK
authors.lastname: Go
authors.forename: Jin Pyo
authors.initials: JP
authors.lastname: Kim
authors.forename: Jeong Ju
authors.initials: JJ
authors.lastname: Seo
authors.forename: Yang Keun
authors.initials: YK
authors.lastname: Rhee
authors.forename: A Mi
authors.initials: AM
authors.lastname: Kim
authors.forename: Dong Jib
authors.initials: DJ
authors.lastname: Na
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D052117:Benzodioxoles / Q000302:isolation & purification / Q000494:pharmacology*; D002460:Cell Line; D045744:Cell Line, Tumor; D002470:Cell Survival; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D005419:Flavonoids / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D017705:Lignans / Q000302:isolation & purification / Q000494:pharmacology*; D031566:Magnolia / Q000737:chemistry*; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D020545:Respiratory Mucosa / Q000378:metabolism*; D012639:Seeds / Q000737:chemistry; D018709:Statistics, Nonparametric; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D052117:Benzodioxoles; D005419:Flavonoids; D053583:Interleukin-1beta; D017705:Lignans; D010936:Plant Extracts; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; C094148:magnolin; D009569:Nitric Oxide; D007371:Interferon-gamma; D052247:Nitric Oxide Synthase Type II; D048049:Extracellular Signal-Regulated MAP Kinases; C539377:fargesin; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one