An Intracellular Lysate Sustained-Release Nanohydrogel Promotes Osteogenesis and Angiogenesis.

INTRODUCTION AND AIMS: Nanomaterials hold great promise for applications in bone tissue engineering. Dental pulp stem cell (DPSC) lysate, as a kind of intracellular lysate, has attracted increasing attention as a bioactive, cell-free therapeutic component in bone tissue engineering. Zeolitic imidazolate framework-8 (ZIF-8), a zinc-based MOF with sodalite topology, features high surface area, porosity and stability under physiological conditions. Its excellent biocompatibility, pH-responsive degradability and drug-loading capacity make it widely applicable in drug delivery.

METHODS

In this study, we developed a strategy for delivering DPSC lysate by encapsulating it within Poloxamer hydrogel and ZIF-8 nanoparticles, successfully synthesising IV@ZIF-8@Poloxamer Hydrogel (INZG).

RESULTS

The resulting INZG exhibited excellent biocompatibility and supported cell viability. In vitro and vivo experiments demonstrated that INZG possessed outstanding osteogenic and angiogenic properties, promoting bone and blood vessel formation via activation of the P38/MAPK and PDGFRβ/PI3K/AKT signalling pathways, respectively.

CONCLUSION

In summary, this study is the first to propose that INZG possess excellent biocompatibility and bioactive functions that promote both osteogenic and angiogenic differentiation.

CLINICAL RELEVANCE: This study provides a safe and effective new strategy for the treatment of various bone defects and lays a theoretical foundation for the development of vascularised bone scaffolds.