Objective：To investigate the effect of coated pitavastatin nanoparticles on re-endothelialization of injured blood vessels and its mechanism of action. Methods：Endothelial progenitor cells were cultured with pitavastatin nanoparticles and transplanted into a rat carotid artery injury model. CCK-8 method was used to observe the proliferation of smooth muscle cells in the injured vascular media. One week later，Evan’s blue staining was used to observe the re-endothelialization，and hematoxylin-eosin staining was used to observe the neointimal hyperplasia of the injured blood vessels. Results：Three days after transplantation of endothelial progenitor cells that endocytosed pitavastatin nanoparticles，fluorescence microscopy showed that endothelial progenitor cells accumulated at the injury site，and the number of homing endothelial progenitor cells in the pitavastatin nanoparticle group was higher than that in the pitavastatin drug group（P=0.025）. Compared with the pitavastatin drug group，the pitavastatin nanoparticle group could significantly inhibit the proliferation of injured vascular smooth muscle cells（P=0.013）. Endothelial progenitor cell transplantation could inhibit intimal proliferation and promote the re-endothelialization of injured blood vessels. The effect of pitavastatin nanoparticles group was more significant than that of the pitavastatin drug group（P=0.043，0.024，respectively）. Conclusion：Pitavastatin nanoparticles can be taken up by endothelial progenitor cells，which can promote their homing to damaged blood vessels，and inhibit smooth muscle cell proliferation at the same time，thereby effectively inhibiting intimal proliferation and promoting re-endothelialization of damaged blood vessels.
