A Study on Traceable Oxygen-Releasing Microspheres in Combination with Bone Marrow Mesenchymal Stem Cells to Enhance...

The treatment of full-thickness skin defects remains a major challenge in clinical medicine. Accelerating wound healing and promoting the restoration of tissue function are of paramount importance. Stem cell therapy has been applied in clinical practice to facilitate wound repair. However, the low survival rate of transplanted stem cells in an ischemic and hypoxic microenvironment severely limits the effectiveness of their clinical application. Microspheres, owing to their excellent biocompatibility and drug delivery capabilities, can serve as effective carriers for oxygen transport. It is worthwhile to evaluate the timing and process of oxygen release under hypoxic conditions. In this study, core-shell structured oxygen-releasing microspheres were prepared and incorporated with the photosensitizer hypericin (HYP) to enable dynamic tracking of the oxygen release process via fluorescent signals. The effects of the oxygen-releasing microspheres on cells under hypoxic conditions were analyzed, focusing primarily on the characterization of the microspheres, their biocompatibility, luminescent properties, and oxygen-releasing capacity. Furthermore, the efficacy of the oxygen-releasing microspheres in combination with bone marrow mesenchymal stem cells (BMSCs) in promoting wound healing was evaluated in vivo. The results indicate that the addition of the microspheres improved cell survival rates in hypoxic environments; meanwhile, their luminescent properties demonstrated the potential of fluorescence intensity as a visual indicator of oxygen release.