Tendon regeneration is still a great challenge due to its avascular structure and low self-renewal capability. The nitric oxide (NO) therapy emerges as a promising treatment for inducing the regeneration of injured tendon by angiogenesis. Here, in this study, a system that NO-loaded metal–organic frameworks (MOFs) encapsulated in polycaprolactone (PCL)/gelatin (Gel) aligned coaxial scaffolds (NMPGA) is designed and prepared for tendon repair. In this system, NO is able to be released in vitro at a slow and stable average speed of 1.67 nM h⁻¹ as long as 15 d without a burst release stage in the initial 48 h. Furthermore, NMPGA can not only improve the tubular formation capability of endothelial cells in vitro but also obviously increase the blood perfusion near the injured tendon in vivo, leading to accelerating the maturity of collagen and recovery of biomechanical strength of the regenerated tendon tissue. As a NO-loaded MOFs therapeutic system, NMPGA can promote tendon regeneration in a shorter healing period with better biomechanical properties in comparison with control group by angiogenesis. Therefore, this study not only provides a promising scaffold for tendon regeneration, but also paves a new way to develop a NO-based therapy for biomedical application in the future.

由于其无血管结构和低自我更新能力，肌腱再生仍然是一个巨大的挑战。一氧化氮 (NO) 疗法作为一种有前途的治疗方法出现，可通过血管生成来诱导受伤肌腱的再生。在这里，在本研究中，设计并准备了一种系统，该系统将 NO 负载的金属有机框架 (MOF) 封装在聚己内酯 (PCL)/明胶 (Gel) 对齐的同轴支架 (NMPGA) 中，用于肌腱修复。^{在该系统中，NO 能够以 1.67 nM h -1}的缓慢而稳定的平均速度在体外释放只要 15 d 在最初的 48 h 内没有爆发释放阶段。此外，NMPGA不仅可以提高体外内皮细胞的管状形成能力，而且可以明显增加体内损伤肌腱附近的血液灌注，从而加速胶原蛋白的成熟和再生肌腱组织的生物力学强度的恢复。作为一种NO负载的MOFs治疗系统，与对照组相比，NMPGA通过血管生成可以在较短的愈合期内促进肌腱再生，具有更好的生物力学性能。因此，本研究不仅为肌腱再生提供了一个有前途的支架，而且为未来开发基于 NO 的生物医学应用疗法铺平了新的道路。