Fabrication of MnO-Modified Decellularized Tendon Membrane for Enhancing Tendon Repair.

Repairing tendon/ligament injuries is a major challenge in sports medicine. It has been reported that tendon injury healing is hindered by massive production of reactive oxygen species (ROS). Manganese oxides nanoparticles are generally non-toxic, can scavenge ROS, promote tissue regeneration, and hold promise for sustainable nanotechnologies. However, the effective and safe integration of MnO nanoparticles on decellularized scaffold mediating tissue repair is still a great challenge. To address these issues, an in situ MnO-modified decellularized scaffold is developed to enhance tendon regeneration through improving microenvironment. The decellularized fibrous membrane is designed and prepared using the central tendon of the porcine diaphragm. Then MnO nanozymes are in situ grown on the collagen fibers using tannic acid (TA) as cross-linking agent and reducing agent. The results showed that MnO-modified scaffold eliminates excessive accumulation of ROS in cells, protects mitochondrial, and maintains the phenotype of tendon cells in an oxidative stress environment. Notably, it is found that the MnO-modified scaffold exhibits good biocompatibility and is able to promote the tendon healing in the rat patellar tendon defect model. Altogether, this study confirmed that this nanozyme-functionalized decellularized extracellular matrix effectively enhanced tendon repair by scavenging ROS, which provides new strategies for enhancing tendon regeneration.