Biomimetic multilayer polycaprolactone/sodium alginate hydrogel scaffolds loaded with melatonin facilitate tendon regeneration.

Tendon injury is one of the most common musculoskeletal diseases in the world, severely challenging the public health care system. Electrospinning technique using polymer materials (i.e. polycaprolactone (PCL)) and hydrogels (i.e. sodium alginate (ALG)) contribute to the development and application of smart composite scaffolds in the tendon tissue engineering by advantageously integrating mechanical properties and biocompatibility. As a potential natural antioxidant, melatonin (MLT) represents the potential to promote tendon repair. Here, we develop an MLT-loaded PCL/ALG composite scaffold that effectively promotes tendon injury repair in vivo and in vitro via a controlled release of MLT, possibly mechanically relying on an antioxidant stress pathway. This biomimetic composite scaffold will be of great significance in the tendon tissue engineering.