Description
The polarization of macrophages into an anti-inflammatory or regulatory phenotype plays an important role in resolving inflammation. PGE2 regulates macrophage polarization via a PKA dependent pathway. PKA phosphorylates SIKs, inhibiting their ability to phosphorylate CRTC3 in cells. This in turn allows CRTC3 to translocate to the nucleus where it acts as a co-activator with the transcription factor CREB to induce IL-10 transcription. In line with this we find that either genetic or pharmacological inhibition of SIKs mimics the effect of PGE2 on IL-10 production.