Over-expression of microRNA-223 inhibited the proinflammatory responses in Helicobacter pylori-infection macrophages by down-regulating IRAK-1.

MicroRNA-223 plays an important role in the inflammatory response of macrophages. Recent studies have identified that miR-223 was highly expressed in H. pylori infection macrophages, the significance of the elevation, however, has not yet been investigated. In this study, we analyzed the impact of elevated miR-233 to macrophage inflammatory response and possible mechanisms. We found that miR-223 not only could inhibit the expression of inflammatory cytokines including IL-6, IL-8, IL-12 and TNF-α, but also was able to decrease the expression of CD40, CD68, CD80, and CD163. Furthermore, proteins relating to inflammatory signal pathways, such as IRAK-1, NF-κB and MAPK, in H. pylori infected macrophages were down-regulated. Taken together, these results indicated that miR-223 may act as an inflammatory inhibitory factor in H. pylori infected macrophages by IRAK-1, NF-κB or MAPK signal pathways. These findings contribute to the understanding of miR-223 in macrophages inflammatory responses induced by H. pylori.