Induction of macrophage polarization by electrospun nano-yarn containing naproxen sodium to promote tendon repair

Excessive inflammatory response can lead to failure of the tendon repair surgery. Tendon substitutes that can effectively balance inflammatory responses and have sufficient mechanical properties are one of the key factors in promoting repair. In this study, the nanofibers containing the naproxen sodium were attached to polylactic acid micron yarn by electrospinning to obtain double-layer core-spun yarn (DY). The DY was knitted into a tendon tissue engineering scaffold with sufficient mechanical properties. This study confirmed the optimal loading concentration of naproxen sodium. The results in vitro and in vivo indicated that sustained-release naproxen sodium in scaffolds could effectively inhibit the rapid proliferation of foreign fibroblasts, accelerate the polarization of macrophages, reduce the inflammatory response, and promote tendon tissue repair. This study provides a new scaffold for tendon tissue engineering that not only serves as a substitute for tendon repair, but also serves as an anti-inflammatory agent to better promote the repair process.