Effects Of MicroRNA-133b Activator On Airway Inflammation In Mice With Combined Allergic Rhinitis And Asthma Syndrome

Objective:This study mainly investigated the effects of micro RNA-133 b activator on airway inflammation in mice with Combined Allergic Rhinitis and Asthma Syndrome(CARAS).Methods:BALB/ C mice were randomly divided into blank group,CARAS group and Micro RNA-133 b activation group.In addition to the blank group,both the CARAS group and the Micro RNA-133 b activation group were sensitized by intraperitoneal injection and intranasal instillation of ovalbumin(OVA)sensitization solution for 3 weeks,and were nebulized with 20g/L OVA for 5 consecutive days to establish the mouse model of Combined Allergic Rhinitis and Asthma Syndrome.The micro RNA-133 b activation group was injected with the corresponding micro RNA-133 b agomir into the nasal cavity and rat tail vein 3 hours before each nebulization challenge,while the CARAS group was injected with the corresponding micro RNA-133 b NC,and the blank group was treated with the same volume of normal saline.The level of micro RNA-133 b in each group was determined by real-time fluorescence quantitative nucleic acid amplification system(q-PCR).The levels of serum interleukin(IL)-17 A,IL-18,IL-6 and IL-1β were determined by enzyme-linked immunosorbent assay(ELISA).Westernblot analysis(Westernblot)was used to detect the expression levels of toll-like receptor 2(TLR2),nucleotide binding oligomerization domain like receptor family pyrin domain protein 3(NLRP3)and nuclear factor p65(NF-kappa Bp65)protein phosphorylation in lung and nasal mucosal tissues of mice.The total number of white blood cells and eosinophil and eosinophil ratio in bronchoalveolar lavage fluid(BALF)were calculated by Rayman’s staining.The pathological changes of lung and nasal mucosa were observed by HE staining.Pearson correlation analysis was used to analyze the correlation between micro RNA-133 b level and TLR2,NLRP3,NF-Kappa Bp65,IL-17 A and IL-1β protein levels in the Micro RNA-133 b activation group.Results:1.The expression level of micro RNA-133 b in nasal mucosa and lung tissues of mice in Micro RNA-133 b activation group was significantly higher than that in the blank group and CARAS group,with statistical significance(P<0.05).2.The lung tissue and nasal mucosa of mice in the CARAS group were disorganized,accompanied by infiltration of various inflammatory cells and degeneration of epithelial cells,while the airway damage and infiltration of inflammatory cells in the Micro RNA-133 b activation group were significantly less than that in the CARAS group.In blank group,nasal mucosa and lung tissue structure and inflammatory cell distribution were normal.3.The frequency of nasal wiping and sneezing,the total number of leukocytes and eosinophils,the ratio of eosinophils and the levels of cytokines(TLR2,NLRP3,NF-Kappa Bp65,IL-17 A and IL-1β)were significantly different among the three groups(P<0.05).Compared with the CARAS group,the above indicators in Micro RNA-133 b activation group were significantly reduced,with statistically significant differences(P<0.05).There was no significant difference in serum IL-18 and IL-6 expression levels among the three groups(P>0.05).4.Micro RNA-133 b levels were negatively correlated with TLR2,NLRP3,NF-Kappa Bp65,IL-17 A and IL-1β in the Micro RNA-133 b activation group(r=-0.77～-0.56,P<0.01).Conclusion:1.The level of micro RNA-133 b in CARAS mice was decreased,and micro RNA-133 b activator could significantly improve the level of micro RNA-133 b in CARAS mice.2.Micro RNA-133 b activator can reduce airway inflammation in CARAS mice.3.Micro RNA-133 b activator may improve CARAS by inhibiting the activation of TLR2/NLRP3 signaling pathway.