RESUMEN
In this study, we describe the synthesis of an upright nanotubular coating with discrete, exposed nanotubes on top of superelastic Nitinol via anodization and characterization of the surface elemental composition and nickel release rates. We demonstrate, for the first time, that this coating could improve re-endothelialization by increasing the cell spreading and migration of primary human aortic endothelial cells on Nitinol. We also show the potential for reducing neointimal hyperplasia by decreasing the proliferation and expression of collagen I and MMP-2 in primary human aortic smooth muscle cells (HASMC). Furthermore, we did not observe the nanotubular surface to induce inflammation through ICAM-1 expression in HASMC as compared to the flat control. This coating could be used to improve Nitinol stents by reducing restenosis rates and, given the extensive use of Nitinol in other implantable devices, act as a generalized coating strategy for other medical devices.
Asunto(s)
Aleaciones/química , Células Endoteliales/citología , Endotelio Vascular/citología , Nanotecnología/métodos , Aorta/citología , Materiales Biocompatibles/química , Movimiento Celular , Proliferación Celular , Colágeno Tipo I/metabolismo , Reestenosis Coronaria/patología , Citometría de Flujo , Humanos , Inflamación , Molécula 1 de Adhesión Intercelular/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Miocitos del Músculo Liso/citología , Nanotubos/química , Stents , Propiedades de SuperficieRESUMEN
Current approaches to reducing restenosis do not balance the reduction of vascular smooth muscle cell proliferation with the increase in the healing of the endothelium. Building on our previous work, we present our study on the effects of Nitinol-based nanotubular coatings with different nanotube diameters on the reduction of restenosis. Here, we demonstrate that the nanotubular coatings reduced primary human aortic smooth muscle cell (HASMC) proliferation and increased the migration (by more than 4 times), collagen (by 2-3 times per cell) and elastin (by 5-8 times per cell) production of primary human aortic endothelial cells (HAEC). Furthermore, a significant increase in elastin and soluble collagen production of HAEC was observed with an increase in nanotube diameter. Our findings suggest that nanotubes-coated Nitinol may provide a surface conducive for HAEC reendothelialization while reducing the proliferation of HASMC.