Circulating miR-125b but not miR-125a correlates with acute exacerbations of chronic obstructive pulmonary disease and the expressions of inflammatory cytokines

To investigate the correlation of miR-125a/b expression with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) patients and inflammatory cytokines.Eighty-seven AECOPD patients, 93 stable chronic obstructive pulmonary disease (COPD) patients and 100 health volunteers (HCs) were recruited. Plasma samples were collected from AECOPD patients at the day 1, day 7, day 14, and day 28 of admission and from stable COPD patients as well as HCs. Total RNA was extracted from plasma, and miR-125a/b relative expressions were determined by quantitative real time-polymerase chain reaction.MiR-125b had a great capacity for distinguishing AECOPD from stable COPD (AUC=0.926, 95% CI: 0.884-0.967) and HCs (AUC=0.923, 95% CI: 0.880-0.966), while miR-125a did not. There were associations between miR-125b expression with TNF-, IL-8, and LTB-4 in AECOPD patients (P=.012, P=.032, and P=.047, respectively), while no correlation of miR-125a with inflammatory cytokines was found. MiR-125b expression gradually decreased at day 7, day 14, and day 28 compared with day 1 (all P<.05) on admission, while no difference in miR-125a was discovered between each visit compared to day 1. Besides, TNF-, IL-1, IL-8, and LTB-4 were elevated in AECOPD patients compared with stable COPD patients (all P<.01).MiR-125b, but not miR-125a, was positively associated with inflammatory cytokines and could be a novel biomarker for distincting AECOPD from stable COPD patients and HCs.