Abstract
Introduction: The new phenotype of ACOS is described clinically as persistent airflow limitation combined with features of both asthma and COPD. miR-145 and miR-338 are involved in respectively in inflammation and tissue remodeling and their role was investigated in COPD and Asthma. The aim of this study was to evaluate the sputum level of miR-145 and miR-338 in ACOS patients compared with Asthma and COPD.
Methods: Sputum samples were obtained from 31 BPCO (yrs 70±8; FEV1% 59±23.4), 10 Asthma patients (yrs 52±14.3; FEV1% 93±11.8) and 6 ACOS (yrs 62±9.4; FEV1%74±10.3) selected according to Spanish guidelines. The RNA was isolated from supernatant of sputum with mirVana™ miRNA Isolation Kit (Ambion, Austin, TX) according to the manufacturer's protocol, the cDNA was processed using 7300 RealTime PCR. The data were than analyzed by ΔCt methods.
Results: Expression of miR-338 was lower in asthma group compared with COPD (-3.02±1.9 vs 0.22±2.4, p<0.01) while ACOS group shows an intermediate expression among two groups. miR-145 was positive expressed in all groups even if any changes were found among none of them. As expected, the percentage of neutrophils were higher in COPD (81±22.5) while higher level of eosinophils was found in ACOS group (21±34.4). miR-338 expression was positive correlated with neutrophils percentage (r=0.34, p=0.04).
Conclusion: This study provides the evidence that there is a different miRNA expression profile in sputum of COPD, ACOS and Asthma subjects.
- Copyright ©the authors 2016