Expression of Human DAMPmiRs

ABSTRACT: Endogenous damage associated molecular pattern molecules (DAMPs) released from necrotic, damaged or stressed cells are associated with an inflammatory response. Whether the microRNA expression signature of this response is different from that of a PAMP-stimulated inflammatory response is unknown. We report here that miR-34c and miR-214 are significantly expressed in fresh human PBMCs exposed to DAMPcontaining freeze-thaw lysates, or to conditioned media from serum-starved and glucose-deprived cells (p<6x10-4 and p<3.7x10-3), respectively. Interestingly, only miR-34c expression was differentially expressed in PBMCs exposed to freeze-thaw lysates or conditioned media from HMGB1+/+ mouse embryonic fibroblast (MEF) cells, when compared to cultures exposed to lysates or conditioned media from HMGB1-/- MEFs. miR-155 expression in these cultures was negligible, but was significantly higher in PBMCs stimulated with LPS or most other TLR ligands, making it the prototypic PAMPmiR. Exposure to a damaged human colorectal carcinoma cell line lysate (HCT116) similarly resulted in increased miR-34c and miR-214 levels. When PBMCs were pre-transfected with anti-miR-34c and then exposed to lysate, expression levels of IKKgamma mRNA, a putative target of miR-34c, increased, while protein levels of IKKgamma in cultures transfected with a pre-miR-34c were abrogated. Levels of miR-34c expression (as well as pro-inflammatory cytokines, IL-1beta and TNFalpha) decreased when PBMC cultures were briefly pre-incubated with the K+ channel (inflammasome) inhibitor, glybenclamide, suggesting that miR-34c is involved in the inflammasome pathway in response to DAMPs. Our findings suggest that a specific microRNA expression signature is associated with the inflammatory response to damaged/injured cells and carries implications for many acute and chronic inflammatory disorders.

ORGANISM(S): Homo sapiens

PROVIDER: GSE37399 | GEO | 2013/03/22

SECONDARY ACCESSION(S): PRJNA159895

REPOSITORIES: GEO