miR-133a-3p targeted regulating CD2AP gene reduces RSV-infected damage of human bronchial epithelial 16-HBE cell line

Objective To explore the effect of miR-133a-3p on the apoptosis and inflammatory response of bronchial epithelial cells infected by respiratory syncytial virus (RSV) and its regulatory effect on CD2-associated protein (CD2AP). Methods The bronchial mucosal tissue specimens from 59 children with bronchial asthma were collected as the AsP group and 59 bronchial mucosal tissue specimens from non-asthmatic children with bronchiec- tasis were selected as the NC group. RT-qPCR method was used to detect the expression of miR-133a-3p and CD2AP in the tissues. RSV infected bronchial epithelial cells (16-HBE) were used to establish a cell injury model (RSV group). miR-NC, miR-133a-3p mimics, si-NC, si-CD2AP, pcDNA-NC, pcDNA-CD2AP, miR-133a-3p mimics and pcDNA-NC, miR-133a-3p mimics and pcDNA-CD2AP were respectively transferred into 16-HBE cells infected with RSV. RT-qPCR and Western blot were used to detect the expression of miR-133a-3p and CD2AP in the cells. ELISA was used to detect the level of TNF-α, IL-6, and IL-1α. Flow cytometry was used to detect apoptosis . The dual luciferase reporter experiment was used to detect the targeting relationship between miR-133a-3p and CD2AP. Western blot method was used to detect the protein expression of cleaved-caspase-3. Results Compared with NC group, the expression of miR-133a-3p in the bronchial mucosa tissue of the AsP group was decreased (P＜0.05), and the expression of CD2AP mRNA was increased (P＜0.05). The expression of miR-133a-3p in RSV-infected 16-HBE cells was decreased (P＜0.05), and the expression level of CD2AP, TNF-α, IL-6 and IL-1α was increased (P＜0.05), the apoptosis rate and the protein level of cleaved-caspase-3 were increased(P＜0.05). Transfection of miR-133a-3p mimics or transfection of si-CD2AP into RSV-infected 16-HBE cells significantly reduced the level of TNF-α, IL-6, IL-1α, the apoptosis rate and the protein level of cleaved-caspase-3 (P＜0.05). The dual luciferase report experiment confirmed that CD2AP was the target gene of miR-133a-3p. Co-transfection of miR-133a-3p mimics and pcDNA-CD2AP significantly reversed the effects of miR-133a-3p mimics transfection on 16-HBE cell apoptosis and inflammation. Conclusions The over-expression of miR-133a-3p inhibits the inflammatory response and apoptosis of RSV-infected bronchial epithelial cells by negatively regulating the expression of CD2AP and thereby reducing cell damage.