The effect of REDV/TiO 2 coating coronary stents on in-stent restenosis and re-endothelialization

The coronary artery stent has been widely used in clinic. In-stent restenosis was mainly caused by the excessive proliferation of smooth muscle cell and the inflammation due to the metal ion released from stent scaffold of the drug-eluting stent. Thus, to reduce the in-stent restenosis and promote the vascular endothelialization have become a hot research point in this area. In this paper, a nano-TiO₂ ceramic coating was deposited on 316L stainless steel to reduce the metal ion release and to inhibit the inflammation reaction. An endothelia cell selective adhesion peptide Arg-Glu-Asp-Val (REDV) coating was prepared on the ceramic coating by a polydopamine technology to promote the endothelialization. The corrosion test indicated that nano-TiO₂ ceramic film could effectively decrease the nickel ion released from 316L stainless steel. REDV/TiO₂ coating could promote the endothelial cell adhesion and proliferation, meanwhile REDV/TiO₂ coating could also increase the nitric oxide concentration. Bare metal stent, TiO₂-coated stent and REDV/TiO₂-coated stent were implanted in the iliac arteries of rabbit model. In-stent restenosis and re-endothelialization were evaluated at 28 days post-implantation of the stents. The results showed that REDV/TiO₂-coated stents could effectively reduce in-stent restenosis and promote re-endothelialization in comparison with TiO₂-coated drug-eluting stent and bare metal stent. These results suggest that REDV/TiO₂-coated drug-eluting stent maybe a good choice of the application for coronary artery disease.