Mechanism of action of miRNA-146a in sepsis-induced acute lung injury

Object To study the expression of miRNA-146a in sepsis-induced acute lung injury (ALI) patients and its effect on the inflammation in mouse models. Methods miRNA-146a expression in peripheral blood was determined in sepsis-induced ALI patients and healthy volunteers by qRT-PCR. Sepsis-induced ALI mouse model were reproduced by LPS treatment and miRNA-146a mimic, miRNA-146a NC and miRNA-146a inhibitors were injected through trachea. The expressions of miRNA-146a, TNF-α, IL-1βand COX-2 mRNA were determined by qRT-PCR 24h after the intervention. Results The miRNA-146a expression in peripheral blood significantly increased in severe sepsis with ALI patients, compared with the control subjects. For mouse model, the expressions of TNF-α, IL -1βand COX-2 mRNA significantly decreased in miRNA-146a group, while increased in miRNA146a inhibitor group compared with miRNA-146a NC group (P<0.05). The TNF-αand IL-1βexpressions significantly decreased in miRNA-146a inhibitor+COX-2 inhibitor group compared with miRNA-146a inhibitor group (P