Micro-RNA gene expression during and after asthma attack for children diagnosed with asthma

Purpose: This work has a goal for identifying new biomarkers on the severity of asthma exacerbation and/or clinical severity of disease via determining levels of miRNA expression for children diagnosed with asthma. Materials and Methods: 34 children with asthma attacks are involved in this study. Same patients are reevaluated once again when they are under control period. Anamnesis information, physical therapy symptoms, laboratory findings and medicine usage are evaluated for both of the patient groups. Asthma control test (ACT) and asthma control scale (ACS) are applied, asthma control level (ACL) and clinical severity of asthma (CSA) are determined. MiRNA gene-expression levels in breath are determined for both groups. Result: In this study, during asthma attack the level of low expression in miR-133a (p=0.015) and the level of high-expression of miR-21 (p=0.008) & miR-126 (p=0.029) in breath shows the severity of asthma attack. Over-expression of miR-133a (p=0.028,r=0.316) in breath shows the high level of preFEV1(%) in SFT and lower-expression of miR-133a (p=0.024) in breath shows that CSA is heavy in the children patients with and without attacks. The lower expression of miR-155 in breath shows ACL (p=0.003), ACS (p = 0.044), CSA (p=0.001), the lower expression of miR-21 level in breath shows that the ACT (p=0.027) is better in the group of patients without attacks. Investigating miRNAs in breath of the children patients with asthma may have the potential to discover novel biomarkers in order to assign the severity of asthma. Keywords: Asthma attack, asthma control, children, breath, miRNA, potential biomarker