The Role Of Nerve Growth Factor And ERK Signaling Pathway In Asthma Airway Remodeling And The Intervention Research Of Chaipu Decoction

Objective:To observe the effect of chaipu decoction on ovalbumin(OVA)-induced asthmaairway remodeling in rats and the expression of nerve growth factor(NGF)、p-ERKand c-fos.Methods：50SD rats，weight(220±20）g, were randomly divided into5groups,10each:acontrol group,a asthma model group,a NGF-Ab-treated group,adexamethasone-treated group and a chaipu decoction-treated group. Asthma rat modelwas established by sensitization and stimulation with ovalbumin(OVA) conjunctedwith Al(OH)3. The rats pathological changes and airway morphological parameterschanges were performed by HE staining,and the expression of nerve growthfactor(NGF)、p-ERK and c-fos in the lung of rats were evaluated by reversetranscription polymerase chain reaction (RT-PCR) and immunohistochemical.Pearsonlinear corrrlation analysis were carried out for statistical analysis.Results：1.The WAt/Pbm,WAi/Pbm,and WAm/Pbm were significantly lower in thecontrol group as compared to the asthma model group,NGF-Ab-treatedgroup,dexamethasone-treated group and chaipu decoction-treated group(allP<0.05),and the WAt/Pbm,WAi/Pbm,and WAm/Pbm were significantly lower inthe NGF-Ab-treated group,dexamethasone-treated group and chaipu decoction-treatedgroup as compared to the asthma model group(all P<0.05).There were no significancedifference among the NGF-Ab-treated group,dexamethasone-treated group and chaipudecoction-treated group(all P＞0.05). 2. the expression of NGF and C-fos mRNA were lower in the control group ascompared to the asthma model group,NGF-Ab-treated group,dexamethasone-treatedgroup and chaipu decoction-treated group(all P<0.05),and the the expression of NGFand C-fos mRNA were significantly lower in the NGF-Ab-treatedgroup,dexamethasone-treated group and chaipu decoction-treated group as comparedto the asthma model group(all P<0.05).There were no significance difference amongthe NGF-Ab-treated group,dexamethasone-treated group and chaipu decoction-treatedgroup(all P＞0.05).3. The expression of NGF、P-ERK and C-fos protein were lower in the c-ontrol group as compared to the asthma model group,NGF-Ab-treated group,dexamethasone-treated group and chaipu decoction-treated group(all P<0.05),and thethe expression of NGF and C-fos protein were significantly lower in the NGF-Ab-treated group,dexamethasone-treated group and chaipu decoction-treated gr-oup as compared to the asthma model group(all P<0.05).There were no signifi-cance difference among the NGF-Ab-treated group,dexamethasone-treated groupand chaipu decoction-treated group(all P＞0.05).4. The expression of NGF protein and p-ERK protein were positively associated（r=0.888,p＜0.01）； The expression of NGF and c-fos were positively associatedr=0.803,p＜0.01）；A significant positively correlation was found among the NGF、p-ERK and c-fos and Wam/Pbm in the bronchial and lung tissues(r=0.706，0.701,0.795，all p＜0.01）.Conclusions:1.NGF might through P-ERK/C-fos conduct pathway participate in asthma airwayremodeling.2.The chaipu decoction may through downregulating the P-ERK/C-fos signal conductpathway to reduce the expression of NGF.