MiR-223-3p regulates the eosinophil degranulation and enhances the inflammation in allergic rhinitis by targeting FBXW7.

OBJECTIVES: MiR-223-3p is a multifunctional microRNA regulated by multiple transcription factors and plays a critical role in inflammation. This paper was designed to investigate the regulatory role and mechanism of miR-223-3p in eosinophils degranulation and allergic rhinitis (AR) inflammation. METHODS: OVA sensitized AR mouse model and EOL-1 cells model were established. RT-qPCR and FISH were performed to detect the miR-223-3p expression. ELISA and WB were utilized to evaluate mRNA and protein expression. HE staining and transmission electron microscopy were applied to observe the morphological changes in nasal mucosa. Flow cytometry and immunofluorescence staining were performed to measure the proportion of eosinophils and eosinophilic major basic protein expression. The targeting relationship between miR-223-3p and FBXW7 was verified by bioinformatic analysis and dual-luciferase reporter gene assay. The expression of FBXW7 was detected by immunohistochemistry. RESULTS: The level of miR-223-3p in nasal mucosa was significantly up-regulated in AR group. The expression of miR-223-3p, ECP, MBP, and EPO were increased in EOL-1 cells, further increasing the miR-223-3p level could promote the ECP and EPO mRNA expression. Upregulation of miR-223-3p increased eosinophils granule protein expression, aggravated mucosal destruction and enhanced AR inflammation. Luciferase assay verified miR-223-3p directly target the 3'-UTR of FBXW7. In vitro, overexpression of FBXW7 could reverse the increase in MBP expression caused by the up-regulation of miR-223-3p. In vivo, knockdown of FBXW7 could reverse the down-regulation in granule protein level caused by the down-regulation of miR-223-3p, thereby aggravating AR inflammation. CONCLUSION: Collected evidence elucidated that miR-223-3p could regulate the eosinophil degranulation and enhances the inflammation in AR by targeting FBXW7. The miR-223-3p/FBXW7 axis may provide a novel approach for AR treatment.

MicroRNA-155-5p regulates the Th1/Th2 cytokines expression and the apoptosis of group 2 innate lymphoid cells via targeting TP53INP1 in allergic rhinitis.

As a key component of innate immunity, group 2 innate lymphoid cells (ILC2s) play a key role in Allergic rhinitis (AR). We previously demonstrated that both miR-155-5p and ILC2s are overexpressed in the nasal mucosa of AR patients, but the underlying mechanism remains unclear. At present study, we revealed that miR-155-5p was highly expressed in ILC2s of AR patients. Moreover, miR-155-5p promoted the secretion of Th2 cytokines of ILC2s, while inhibited the secretion of Th1 cytokines and the apoptosis of ILC2s. Meanwhile, the TP53INP1 expression was poorly expressed in ILC2s of AR patients. A dual luciferase reporter assay demonstrated that TP53INP1 was a direct target of miR-155-5p, and its expression was inversely associated with miR-155-5p in ILC2s. Furthermore, TP53INP1 inhibited the secretion of Th2 cytokines of ILC2s, while promoted the secretion of Th1 cytokines and the apoptosis of ILC2s. Notably, rescue experiments demonstrated that overexpression of TP53INP1 could partially reverse the effect of miR-155-5p on ILC2s. Taken together, these findings suggested that miR-155-5p aggravated the inflammatory response of AR dominated by ILC2s via targeting TP53INP1, which may aid in the development of novel therapeutic agents for AR.