Extracts of Magnoliae flos inhibit inducible nitric oxide synthase via ERK in human respiratory epithelial cells.
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.
Baek
Jin Ah
JA
Department of Internal Medicine, Eulji University School of Medicine, Seo-Gu, Daejeon, Republic of Korea.
Lee
Yang Deok
YD
Lee
Chan Bog
CB
Go
Hyeon Kyu
HK
Kim
Jin Pyo
JP
Seo
Jeong Ju
JJ
Rhee
Yang Keun
YK
Kim
A Mi
AM
Na
Dong Jib
DJ
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
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