Vitamin D Participates In The Progression Of Obese Asthma Rats By Affecting The Expression Of ILC2

Objective:To observe the effect of vitamin D on ILC2 in obese asthmatic rats,and to explore the effect and mechanism of vitamin D on obese asthma.Methods:According to the principle of randomization,the 40 healthy SD mice(weighing 130±10g)g were split into 5 groups(n=8 per group):normal control group,asthma group,obesity asthma group and obese asthma + vitamin D intervention group(referred to as intervention group).(1)The normal group and the asthma group were fed with normal diet.Obese group,obese asthma group and intervention group were fed with high fat diet to establish obese rat model;(2)Except for the normal group,all the other groups were given OVA mixture 0.1ml/only(Albumin+aluminum hydroxide,OVA+AL(OH)3)sensitization,intranasal instillation of LPS 10?g(20?l)and 1%OVA multiple aerosol stimulation to produce steroid-resistant ast hma model,The intervention group was given vitamin D(25 ?g/kg/d)before each physicochemical challenge;(3)Mice were sacrificed 24 hours after the last aerosolization.HE staining and pathology image analysis were performed on lung tissues.(4)The relative expression of IL-5,IL-13 and RORa protein in lung tissue of each group was detected by immunohistochemistry.;(5)The expression of RORa mRNA in lung tissue of each group was detected by qRT-PCR;(6)Pulmonary arterial blood was centrifuged and the changes of serum vitamin D in each group were detected by ELISA.Results:1.HE staining showed no pathological changes in the lung tissue of normal and obese rats.Bronchial stenosis was observed in lung tissues ofasthmatic model rats,with a large number of inflammatory cells around and alveolar wall rupture.The lung tissue of the obese asthma group is more serious than the asthma group.Significant improvement in lung tissue in obese asthma rats after vitamin D intervention.2.Immunohistochemical results of IL-5,IL-13 and RORa in rat lung tissue IL-5,IL-13 and RORa were significantly increased in the asthma group and the obese asthma group compared with the normal group(P<0.05).The expression of IL-5,IL-13 and RORa in obese asthmatic rats was higher than that in asthmatic rats(P<0.05).IL-5,IL-13 and RORa expression decreased compared with obese asthma group after vitamin D intervention(P<0.05).3.Expression of RORa mRNA in rat lung tissue RORa mRNA expression was highest in the obese asthma group.ROR? mRNA expression decreased after vitamin D intervention,and there was a significant difference compared with obese asthma group(P<0.05).The expression of ROR in lung tissue of obese asthma mice decreased after vitamin D intervention(P<0.05).4.Expression of vitamin D in rat serum Elisa results show:Compared with the normal control group,the expression of vitamin D was significantly down-regulated in the asthma group and the obese asthma group(P<0.01).The expression of vitamin D in the obese asthma group was lower than that in the asthma group(P<0.05).Conclusion1.Inflammatory changes in obese asthma rats are associated with abnormal expression of ILC2 s.2.Vitamin D may participate in the pathogenesis of obese asthmatic rats by regulating the expression of ILC2.