NFKB1 and rheumatoid arthritis: MiR-146a, therefore, constitutes an essential part of a negative feedback loop in macrophages that attenuates the activation of NF-κB signaling and reduces the production of inflammatory factors.119 Nevertheless, since miR-146a expression in macrophages reaches saturation at sub-inflammatory levels,122 it appears that the abnormal miR-146a expression in RA is not sufficient to counteract the positive effect of miR-155 on NF-κB activity, thus contributing to the chronicity of inflammation.