Abstract
Normal endothelial cell dependent vascular smooth muscle cell function is mediated by nitric oxide (NO), which stimulates soluble guanylyl cyclase (sGC) production of the second messenger cyclic guanosine monophosphate (cGMP) leading to increased protein kinase G (PKG) activity and vascular smooth muscle relaxation. NO bioavailability is impaired in high glucose (HG). We tested the hypothesis that the sGC sensitizer vericiguat reverses HG-mediated decreased sGC activity in two experimental models, human aortic vascular smooth muscle cells (HVSMCs) and isolated mouse aortic rings. HVSMCs were exposed to normal glucose (NG) or to HG with or without 1 μm vericiguat for 24 h and cGMP and PKG activity were measured. Murine aortic rings were incubated in NG or HG for 24 h. Following incubation, the aortic rings were placed in an organ chamber bath containing the same NG or HG concentration used during the incubation. Dose-response curves to increasing concentrations of acetylcholine (ACh) and sodium nitroprusside were constructed for four groups: control (NG), NG + vericiguat, HG, and HG + vericiguat. As compared with the results in the NG group, cGMP production and PKG activity were significantly impaired in the HG cells incubated without, but not in those incubated with, vericiguat. In isolated aortic rings, ACh-mediated relaxation was impaired following treatment with HG, but not when a HG group was treated with vericiguat. The findings suggest clinical studies are warranted to investigate the potential of sGC sensitization as a therapeutic intervention to improve vascular NO-cGMP signaling endothelium -dependent function that is impaired in HG settings such as diabetes and the metabolic syndrome.