MicroRNA miR-21 and miR-146a expression in male with a combination of bronchial asthma and chronic obstructive pulmonary disease

Patients with a combination of bronchial asthma (BA) and chronic obstructive pulmonary disease (COPD) crossed phenotype (CP) BA and COPD are a separate nosological group. CP BA and COPD is a multifactorial disease. There is a hypothesis that genetic control of CP BA and COPD development at the posttranscriptional level is carried out by regulation of gene expression involving microRNA (miR) miR-21 and miR-146a; these molecules can be considered as potential diagnostic markers of CP BA and COPD. The purpose of this study was to evaluate the expression of miR-21, miR-146a in male with a combination of BA and COPD compared to those with isolated BA and COPD. Materials . We examined male patients (n = 65) (n = 48: 19 patients with CP BA and COPD; 14 patients with BA and COPD) and control group (n = 17). All the patients underwent a comprehensive clinical-laboratory and instrumental examination. The expression of miR-21, miR-146a was estimated in peripheral blood by a real-time polymerase chain reaction. Results . CP BA and COPD have lower levels of miR-21 and miR-146a than the BA, COPD, and control groups. CP BA and COPD patients have low levels of miR-21 and miR-146a associated with shorter duration of the disease and the presence of comorbid pathology (hypertension, angina pectoris), revealed in patients with the disease debut at an older age. Low miR-21 was associated with lower reversibility of bronchial obstruction in these patients, despite eosinophilic inflammation in the bronchi. Conclusion . It has been demonstrated that within the framework of complex diagnostics of CP BA and COPD in males it is reasonable to evaluate miR-146a and miR-21 expression in peripheral blood. MicroRNA miR-146a and miR-21 are promising molecular targets for phenotype-specific therapy in males with CP BA and COPD.