Objective: To investigate the pathogenesis of miRNA in asthma by measuring the microRNAs (miRNAs) levels in the bronchoalveolar lavage fluid (BALF) cells of children with asthma.
Methods: A total of 15 children with asthma were enrolled as the asthma group and another 13 children who were subjected to airway foreign removal within 24 hours were enrolled as the control group. The levels of miRNAs were measured by miRNA microarray and verified by qRT-PCR. The expression of target genes E-cadherin was assessed as well.
Results: A total of 65 miRNAs in the BALF cells of the asthma group were different from those in the control group. Six miRNAs of miR-34/449 family and seven miRNAs of miR-200 family were decreased. For 13 differentially expressed miRNAs, qRT-PCR confirmed that 10 miRNAs were consistent with the results of miRNAs microarray, including miR-34b-3p, miR-34b-5p, miR-34c-3p, miR-34c-5p, miR-200a-3p, miR-200a-5p, miR-200b-3p, miR-200b-5p, miR-200c-3p, miR-141-3p. E-cadherin, the predicted target of miR-34/449 family and miR-200 family, was down-regulated in children with asthma as well.
Conclusions: These data suggested that miRNAs, especially the miR-34/449 and miR-200 families, were involved in the mechanism of childhood asthma by regulating E-cadherin expression. Further studies on the mechanism of miRNAs in asthma are required.