Identification of specific microRNAs in diabetic-derived neutrophils

The recruitment and/or retention kinetics of neutrophils in diabetic (db) cutaneous wounds is aberrant, and inflammation is prolonged. Intrinsic factors have been shown to play an important role in aberrant myeloid cell behavior. The pathogenesis of chronic inflammation may be due to dysfunction of db-derived neutrophils. microRNAs (miRNAs) have been shown to globally regulate a large range of biological processes within a cell. Therefore, in order to clarify the molecular mechanism of regulation of inflammation in db-derived neutrophils, we screened for changes in miRNAs in db-derived neutrophils. miRNAs are differentially expressed in db-derived neutrophils, particularly members of the miR-129 family. Our results suggest that deregulation of the miR-129 family contributes to the dysfunction of db-derived neutrophils. The retention kinetics of neutrophils and chronic inflammation may be initiated via miR-129 family-regulated genes such as Casp6, Dedd2 and Ccr2. Neutrophils from pooled bone marrow (BM) of 3 db or 3 non-db mice were isolated using the neutrophil isolation kit, and miRNA was purified by MicroRNA isolation kit, Mouse Ago2. Microarray analysis was performed on a total of 8 pools (4 pools of 3 db BM samples and 4 pools of 3 non-db BM samples) using SurePrint G3 Mouse miRNA microarray.