Activation of vascular inflammatory pathways is an important early step in vascular insulin resistance and in the development of atherosclerosis. Vasodilatory-stimulated phosphoprotein (VASP) was discovered as an important phosphorylated protein in platelets in response to agents that elevate cGMP and cAMP levels. In target cells, NO activates a complex cascade of events. First, NO activates soluble guanylate cyclase leading to cGMP synthesis. cGMP exerts its main biologic activation by activating the cGMP-dependent protein kinase (PKG). Down regulation of sGC and PKG impairs NO function and leads to increased proliferation and vascular constriction. Since NO has well known anti-inflammatory effects, we hypothesized that VASP may mediate NO-dependent inhibition of NF-kB activation. To determine the effects of VASP signaling on endothelial NF-kB and insulin signaling, we overexpressed VASP protein and empty vector constructs in bovine aortic endothelial cells (BAECs). In empty vector-transduced BAEC, palmitate increased NF-kB and attenuated insulin-mediated activation of phospho-Akt and phospho-eNOS, whereas VASP overexpression attenuated palmitate-mediated NF-kB activation and restored insulin signaling in transduced BAEC. These results, suggest that overexpression of VASP is sufficient to reverse the inflammatory effects of palmitate and restore endothelial insulin signaling. We next assessed VASP signaling in vivo in a diet-induced obesity model of insulin resistance. Thoracic aortic lysates were analyzed by western blot for PKG, VASP, and VASP serine 239 phosphorylation (a marker of VASP activity). HF-feeding reduced phospho-VASP levels, without significant changes in total PKG or total VASP levels. Finally, in chow fed VASP-/- mice and litter-mate control mice, we found evidence for increased vascular inflammation and impaired insulin mediated activation of Akt and eNOS in the thoracic aorta in the VASP-/- mice. These findings suggest that, the absence of VASP signaling is sufficient to cause vascular insulin resistance. These data demonstrate that vascular VASP signaling plays an important role in regulating vascular inflammation.