Adiponectin limits monocytic microparticle-induced endothelial activation by modulation of the AMPK, Akt and NFκB signaling pathways

Abstract Objective Monocyte-derived microparticles (mono-MPs) are emerging as critical transducers of inflammatory signals, and have been suggested to link cardiovascular risk factors to vascular injury. Since adiponectin has been proposed to exert multiple anti-inflammatory and vasculoprotective effects, we hypothesized that it might serve to limit the production and/or action of mono-MPs. Methods Flow cytometry and western blot studies were conducted on THP-1 cells, THP-1-derived MPs, human umbilical vein endothelial cells (HUVECs), peripheral blood CD14+ monocytes and mice to evaluate the effects of adiponectin on mono-MPs. Results Adiponectin attenuated lipopolysaccharide (LPS)-evoked MP release from THP-1 monocytes (30% difference) and peripheral blood monocytes (both P in vivo . Furthermore, peritoneal monocytes from Adipoq −/− mice generated significantly greater MPs than those from Adipoq +/+ littermates in the absence (2.3 fold difference, P P Conclusion Adiponectin exerts novel effects to limit the production and action of mono-MPs, underscoring yet another pleiotropic effect of this adipokine.