SNAP23 adenovirus

Disturbed blood flow can promote platelet aggregation and thrombosis by increasing the accumulation of von Willebrand factor (VWF) at sites of arterial post-stenosis. However, the mechanisms by which turbulence regulates endothelial VWF production remain unclear. Here, researchers describe a mouse model in which the left external carotid artery (LECA) is ligated to generate turbulent flow in the common carotid artery. Ligation of the LECA increased the accumulation of VWF in plasma. Application of ferric chloride (FeCl3) induced carotid artery thrombosis, and the thrombosis time was shortened in ligated vessels compared with unligated vessels. In vitro, endothelial cells were subjected to oscillatory shear (OS) or pulsatile shear (PS). OS promoted VWF secretion and platelet aggregation induced by cell-conditioned medium by regulating the intracellular localization of vesicle-associated membrane protein 3 (VAMP3) and synaptosome-associated protein 23 (SNAP23). Disruption of vimentin intermediate filaments inhibited OS-induced translocation of SNAP23 to the cell membrane. Knockdown of VAMP3 and SNAP23 reduced endothelial VWF secretion. Systemic inhibition of VAMP3 and SNAP23 by treating mice with rapamycin significantly ameliorated FeCl3-induced thrombosis, whereas intraluminal overexpression of VAMP3 and SNAP23 exacerbated thrombosis. These findings suggest that VAMP3 and SNAP23 are potential targets for preventing blood flow disturbances that accelerate thrombosis.

For the gain-of-function of VAMP3/SNAP23, adenoviruses expressing SNAP23/VAMP3 (Ad-SNAP23 and Ad-VAMP3) or their control viruses were incubated locally intraluminally before ligation of the mouse common carotid artery (LCA). As expected, ligation of the LECA resulted in increased expression of VAMP3 and SNAP23 in the common carotid artery endothelium 1 week after surgery. Systemic administration of rapamycin inhibited this increase, which was further enhanced by intraluminal application of Ad-VAMP3 and Ad-SNAP23 viruses (Figure 1A-D). Rapamycin treatment significantly reduced VWF levels on the intimal surface. In contrast, intraluminal application of Ad-SNAP23 and Ad-VAMP3 viruses significantly increased VWF levels on the intimal surface (Figure 1E, F). Rapamycin treatment significantly ameliorated FeCl3-induced thrombosis in the mouse carotid artery, prolonging the mean occlusion time from 9.12 ± 2.2 minutes to 13.17 ± 6.07 minutes (Figure 1G). In contrast, intraluminal administration of Ad-SNAP23 and Ad-VAMP3 viruses significantly exacerbated FeCl3-induced thrombosis in the treated arteries compared with the control group (Figure 1H). The mean occlusion time was shortened from 25.88 ± 11.68 minutes to 11.84 ± 2.88 minutes (Figure 1H). These results suggest that VAMP3 and SNAP23 are potential targets for preventing the disturbed flow-accelerated thrombus formation.

Figure 1. VAMP3 and SNAP23 play important roles in disturbed flow-induced thrombosis. (Zhu J J, et al., 2020)