Conclusion
Use of an MnO2 nanoplatform for biological factors release to regulate the IDD microenvironment and promote endogenous repair may be an effective approach for treating IDD.
Methods
Surface morphology and elemental analysis of the MnO2 nanoparticles (NPs) were performed by transmission electron microscopy and an energy-dispersive X-ray spectroscopy detector system, respectively. The biological effects of MnO2 loaded with TGF-β3 (TGF-β3/MnO2) on nucleus pulposus cells (NPCs) were assessed via cytoskeleton staining, EdU staining, qPCR and immunofluorescence. The efficacy of TGF-β3/MnO2 on needle puncture-induced IDD was further examined using MRI and histopathological and immunohistochemical staining.
Results
The MnO2 NPs had a spherical morphology and hollow structure that dissociated in the setting of a low pH and H2O2 to release loaded TGF-β3 molecules. In the oxidative stress environment, TGF-β3/MnO2 was superior to TGF-β3 and MnO2 NPs in the suppression of H2O2-induced matrix degradation, ROS, and apoptosis in NPCs. When injected into the IVDs of a rat IDD model, TGF-β3/MnO2 was able to prevent the degeneration and promote self-regeneration.