Soluble Guanylate Cyclase Agonists Inhibit Expression and Procoagulant Activity of Tissue Factor

Department of Medicine, University Hospital of Northern Norway, Tromsø, Norway.
Arteriosclerosis Thrombosis and Vascular Biology (Impact Factor: 6). 08/2009; 29(10):1578-86. DOI: 10.1161/ATVBAHA.109.192690
Source: PubMed


Tissue factor (TF), a major initiator of blood coagulation, contributes to inflammation, atherosclerosis, angiogenesis, and vascular remodeling. Pharmacological agonists of soluble guanylate cyclase (sGC) attenuate systemic and pulmonary hypertension, vascular remodeling, and platelet aggregation. However, the influence of these novel pharmacophores on TF is unknown.
We evaluated effects of BAY 41-2272 and BAY 58-2667 on expression and activity of TF in human monocytes and umbilical vein endothelial cells (HUVECs). Both compounds reduced expression of active TF protein in monocytes stimulated with lipopolysaccharide, as demonstrated by immunoblotting and a TF procoagulant activity assay. In-cell Western assay revealed that this effect was associated with a marked reduction of total and surface TF presentation. Furthermore, BAY 41-2272 and BAY 58-2667 decreased TF protein expression and the TF-dependent procoagulant activity in HUVECs stimulated with TNF-alpha. The sGC agonists also suppressed transcriptional activity of NF-kappaB. A siRNA-mediated knockdown of the alpha1-subunit of sGC in monocytes and HUVECs confirmed that the inhibitory effect of BAY 41-2272 and BAY 58-2667 on TF expression is mediated through the sGC-dependent mechanisms.
Inhibition of TF expression and activity by sGC agonists might provide therapeutic benefits in cardiovascular diseases associated with enhanced procoagulant and inflammatory response.

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