COPD is a frequent, chronic disease characterized by chronic airflow limitation due to anomalies of the respiratory and/or alveolar tracts, mostly caused by exposure to tobacco. Moreover, it is the third leading cause of death in the world, in consequence their early detection is very important. Some biomarkers, such as miRNAs, could help to identify early. Recently, our group has identified a different miRNAs panel in bronchoalveolar lavage (BAL) from patients with COPD (PMID:35466228)

Aim: create a profile of miRNAs in serum samples that allows the detection of smokers susceptible to suffering from COPD

Methods

Serum sample from 26 patients (14 smokers with normal lung function vs 12 COPD) were analysed to validate BAL?s miRNAs of our previous study: miR-200c-3p, miR-449c-5p, miR-320c; and to validate 2  extra serum miRNAs: miR-210-3p, miR-500a-3p

Results

Median age of population was 60±14 years and IMC 26.3±3.7kg/m2. COPD group presented airflow obstruction (FEV1/FVC 55±77%, FEV1 59±19%), unlike smoker group which airflow was normal (FEV1/FVC 77±5%, FEV1 95±179%, p<0.01). In previous study we observed that miRNAs (miR-200c-3p, miR-449c-5p, miR-320c) were up-regulated in BAL from COPD patients, but interestingly in serum miR-200c-3p and miR-320c were down-regulated (p<0.05) in same patients vs smokers and miR-449c-5p was not detected. Serum miRNAs, miR-210-3p and miR-500a-3p, were down- and up-regulated respectively (p<0.05) in COPD group vs smokers

Conclusion

Expression of serum miRNAs (miR-200c-3p, miR-320c, miR-210-3p y miR-500a-3p) is different in COPD vs smokers. Moreover, the regulation of miRNAs varies depending on its origin, therefore the choice of type of sample to analyzed is very important