Loss of soluble guanylyl cyclase in platelets contributes to atherosclerotic plaque formation and vascular inflammation

Aim The role of platelets in atherosclerosis remains incompletely understood. Variants in genes encoding the soluble guanylyl cyclase (sGC) in platelets are associated with coronary artery disease (CAD) risk. Here we sought to investigate the contribution of platelet sGC to atherosclerosis and the therapeutic potential of targeting sGC in atherosclerosis. Methods and Results We genetically deleted sGC in platelets of atherosclerosis-prone Ldlr -/- mice. By intravital fluorescence microscopy such Pf4- Cre + Gucy1b1 flox/flox Ldlr -/- mice displayed enhanced leukocyte adhesion to atherosclerotic plaques in comparison with their litter mates. Moreover, histological and flow cytometry analyses revealed more numerous inflammatory leukocytes and larger plaque sizes in aortic tissue of Ldlr -/- mice lacking sGC in platelets. In vitro , supernatant from activated platelets lacking sGC promoted leukocyte adhesion to endothelial cells (EC) via enhanced EC activation. Using cytokine profiling, we identified reduced angiopoietin-1 release by Pf4- Cre + Gucy1b1 flox/flox and human GUCY1A1 risk allele carrier platelets to be responsible for enhanced activation of EC and subsequent leukocyte adhesion. Pharmacological sGC stimulation increased platelet angiopoietin-1 release in vitro and reduced recruitment of adoptively transferred leukocytes in Ldlr -/- mice fed a Western diet. Pharmacological sGC stimulation further reduced atherosclerotic plaque formation and vascular inflammation. Conclusion Loss of sGC in platelets contributes to atherosclerotic plaque formation via reduced release of the soluble factor angiopoietin-1 and, subsequently, enhanced leukocyte recruitment. Pharmacological sGC stimulation might represent a novel therapeutic strategy to prevent and treat CAD. Translational perspective Reduced platelet soluble guanylyl cyclase activity contributes to atherosclerotic plaque formation and vascular inflammation. Stimulators of the soluble guanylyl cyclase, an emerging class of drugs already used in pulmonary hypertension and heart failure, are able to reduce atherosclerosis and inflammation in this preclinical model. Together with evidence from human genetics, our findings suggest a promising role of soluble guanylyl cyclase stimulation to prevent coronary artery disease. ### Competing Interest Statement H.S. has received personal fees from MSD SHARP & DOHME, AMGEN, Bayer Vital GmbH, Boehringer Ingelheim, Daiichi-Sankyo, Novartis, Servier, Brahms, Bristol-Myers-Squibb, Medtronic, Sanofi Aventis, Synlab, Pfizer, and Vifor T as well as grants and personal fees from Astra-Zeneca outside the submitted work. H.S. and T.K. are named inventors on a patent application for prevention of restenosis after angioplasty and stent implantation outside the submitted work. T.K. received lecture fees from Bayer AG, Pharmaceuticals. L.D., F.W. and P.S. are full-time employees of Bayer AG, Pharmaceuticals. The other authors have nothing to disclose.