Study On The Expression Of Mucin In Asthma And Effect Of N-acetylcysteine On It

PART? THE EXPRESSION OF MUC5 AC AND MUC5B IN PERIPHERAL BLOOD OF CHILDREN WITH ASTHMAObjective:To investigate the expression of MUC5 AC and MUC5 B in peripheral blood of children with asthma.Methods:From November 2018 to April 2019,36 children with asthma admitted to Children's Hospital of Chongqing Medical University and 25 children from orthopedics were selected as the subjects.The levels of MUC5 AC and MUC5 B mRNA in peripheral blood were detected by Real-time quantitative PCR(q-RT PCR)in the two groups.The levels of mucins MUC5 AC and MUC5 B in plasma were detected by Elisa.The relative expression levels of MUC5 AC and MUC5 B mRNA and the protein expression levels of MUC5 AC and MUC5 B in asthma and control groups were compared.The relationship between clinicalmanifestations and lung function with four kinds of expression products in children was analyzed.Results:Compared with the control group,the expression of MUC5 AC and MUC5 B in the asthma group was higher(P<0.05).In asthma group,the level of MUC5 AC in the cough group was higher than that in the non-cough group(P<0.05).Conclusion:Peripheral blood MUC5 AC and MUC5 B expression is related to bronchial asthma in children,and is related to asthma-related clinical features.Peripheral blood MUC5 AC and MUC5 B expression levels may be used as indicators to assist in the evaluation of mucus hypersecretion in asthmatic children.PART? THE EFFECT OF N-ACETYLCYSTEINE ON AIRWAY MUCUS HYPERSECRETION AND AIRWAY INFLAMMATION IN ASTHMATIC MICEObjective:To investigate the effect of N-acetylcysteine on airway mucus secretion and airway inflammation in asthmatic mice sensitized by house dust mites(HDM).Methods:Six to eight weeks old SPF grade C57 bl / 6 female mice were selected and divided into 3 groups according to the random number table method: control group(Control),asthma group(Asthma),and antioxidants group(NAC group).Mice were established by HDM nasal drip sensitization and stimulation.The control group was sensitized by normal saline.From the first day of HDM nasal drip to the last time End of excitation,the NAC group was intraperitoneally injected with NAC solution 1 hour after the dust mite nasal drip.Within 24 hours of the last challenge,lung function tests were performed to collect bronchoalveolar lavage fluid(BALF),lung tissue and other experimental specimens.Cell count and inflammatory cell count were performed;the pathological changes Of left lung were observed by hematoxylin and eosin(HE)staining;Elisa was used to detect IL-4 levels in BALF;left lung pathological sections were evaluated for lung mucus secretion by glycogen PAS staining;the right lung tissue was detected by real-time fluorescence quantitative polymerase chain reaction(RT-PCR)to detect the expression level of MUC5 AC m RNA;immunohistochemical staining of lung tissue was used to detect the expression of mucin MUC5 AC.Results:The airway hyperresponsiveness(AHR)in the asthma group was higher than that in the control group(P <0.01);the total number of BALF cells was increased(P <0.05);the absolute eosinophil count increased(P <0.05);Inflammatory cell infiltration around tract blood vessels increased(P <0.05);IL-4 increased in BALF;mucus production in airway epithelial cells increased significantly(P <0.01);MUC5AC transcription level in lung tissue increased(P <0.05);airway epithelial MUC5 AC protein expression increased(P <0.05).Compared with the AS group,the airway hyperresponsiveness in the NAC group was reduced(P <0.01);the total number of BALF cells was reduced(P<0.05);the absolute count of eosinophils was reduced(P <0.05);the degree of inflammatory cell infiltration was reduced compared with the asthma group(P <0.05);mucus production in airway epithelial cells was significantly reduced(P <0.05);there was no significant difference in the transcription level of MUC5 AC in lung tissue;MUC5AC protein expression in airway epithelium was reduced(P <0.05).Conclusion:NAC has the therapeutic effect of reducing airway inflammation and reducing airway mucus hypersecretion induced by dust mite-induced asthma.