The Role Of Estrogen Receptor α And β In Phenotypic Transformation,Proliferation And Migration Of Airway Smooth Muscle In Asthma

Objective: To explore the expression levels of estrogen receptor α and β in airway smooth muscle layer in asthmatics and their role in the phenotypic transformation,proliferation and migration of airway smooth muscle cellsMethods: We explore the above-mentioned purpose through three aspects: clinical specimens,animal experiments,and cell experiments.Firstly,we included a total of 10 asthmatic patients and 3 healthy controls who had a smooth muscle layer in airway mucosal section through bronchoscopy.At the same time,we collected basic clinical information of these clinical subjects,including gender,age,BMI,percentage of peripheral blood eosinophils,and lung function test results.Then we used immunohistochemistry to detect the expression of estrogen receptor α and β and Phenotypic marker of airway smooth muscle on the bronchial mucosal sections of clinical subjects and used Image Pro plu6 to measure average integrated optical density of airway smooth muscle layer;secondly we established an OVA-induced asthma model in C57 mice[control group(8 males and 8 females)and asthmatic group(8 males and 8 females)],The right lung tissue of the mouse was taken for paraffin section,We used the same method to detect the expression of estrogen receptor α and β and Phenotypic marker of airway smooth muscle on the lung tissue sections,besides,we measured the thickness of airway smooth muscle layer and PCNA expression positive rate;At last,In the in vitro experiments,the rat primary airway smooth muscle cells were used as the experimental object,Cells were stimulated with IL-4 combined with E2/PPT/DPN to detect changes in the expression of smooth muscle cell phenotype markers,cell proliferation,and then also to detect phenotype markers changes and Cell proliferation after silencing estrogen receptor α and β.In addition,we also used Transwell cell invasion experiments to explore the effects of estrogen receptor α and β on PDGF-induced cell migration.Results: 1)There are no significant difference in airway smooth muscle ERα and ERβ expression between male asthmatics and male controls,male and female asthmatics the expression of ERα and ERβ in the large airway smooth muscle layer of clinical subjects is positively correlated(r=0.65,p=0.0161);2)The expression of ERβ in the RASMCs of female asthmatic mice increased;the RASMCs of female asthmatic mice changed from contractile to synthetic phenotype,and the expression of PCNA also increased;the airway smooth muscle layer of all asthmatic mice was thickened,and female asthmatic mice increased the most;3)The expression of ERβ and PCNA in the large airway smooth muscle layer of asthmatic mice is positively correlated(r=0.33,p=0.036);4)In vitro IL-4 stimulation can promote the increase of ERα and ERβ protein expression in rat airway smooth muscle;5)In vitro Estrogen stimulation can promote the transformation of RASMCs from contractile to synthetic phenotype.Silencing ERα can inhibit the transformation of RASMCs from contractile to synthetic phenotype;6)In vitro E2 and DPN stimulation can promote the proliferation of RASMCs,and the proliferation of RASMCs is weakened after ERβ silence;7)Silencing ERα and ERβ in vitro can inhibit the migration of rat airway smooth muscle cell migration.Conclusions: ERβ can promote the proliferation of asthmatic airway smooth muscle.Both ERa and ERβ play a certain positive regulatory role in the migration of airway smooth muscle induced by PDGF.