Photothermal-promoted calcium influx-regulated phenotypic transformation of VSMCs and free radical scavenging-mediated endothelialization repair for the prevention of in-stent restenosis

Vascular stent implantation is the most direct and effective approach for the treatment of atherosclerosis-related cardiovascular diseases. However, although various stents with the specific features are developed, the in-stent restenosis (ISR) still significantly impacts long-term prognosis of patients and imposes a substantial medical burden. Herein, we coated the bare metal stent (BMS) with polydopamine-Au (PDA-Au) nano-composite and then complexed with Ca 2+ , obtaining BMS@PDA-Au/Ca stent for the prevention of ISR after implantation. Under 808-nm laser irradiation, BMS@PDA-Au/Ca stent increased the temperature around it, further inducing the up-expression of transient receptor potential vanilloid subfamily 1 (TRPV1) of vascular smooth muscle cells (VSMCs). Moreover, BMS@PDA-Au/Ca stent could release Ca 2+ and Ca 2+ was promoted to enter into VSMCs through TRPV1, resulting in the enhanced contractile phenotype and decreased synthetic phenotype of VSMCs. Additionally, PDA with free radical scavenging capacity could accelerate the endothelialization repair. In this way, ISR caused by implantation of stent into the carotid arteries of rabbits could be effectively prevented by using BMS@PDA-Au/Ca stent and laser irradiation. Therefore, this study constructed a novel stent and explored its effect on prevention of ISR, providing an innovative strategy for optimizing the stent implantation treatment of atherosclerotic diseases.