Osteoimmune-regulative metal-organic framework nanomedicine for effective osteoporosis therapeutics

Osteoporosis is a global degenerative bone disorder in the elderly caused by the aging of bone and immune systems. Current therapeutics for osteoporosis focus on medical control over the osteoblast and osteoclast, resulting in complicated procedures and side effects. Regulation of osteoimmunity is of high significance for biocompatible and effective osteoporosis treatment. In the present work, we have designed a strontium phosphate (SP)-coated hollow zeolitic imidazolate framework-8 (hZIF) nanomedicine by chemical mineralization in which vitamin D₃ (VD) has been further encapsulated. The formulated VD@SP-hZIF nanoparticles exhibit robust osteoimmune-regulative effects (anti-inflammatory, pro-osteogenesis, and calcium absorption promotion) in aged murine osteoporotic models respectively due to the constructed moieties of zinc ions, strontium phosphates and the loaded VD. The in-depth osteoporotic therapeutic mechanism of VD@SP-hZIF nanoparticles has also been explored. The present work highlights the construction of the metal-organic framework nanomedicines for effective regulation of osteoimmune microenvironment against osteoporosis, providing a highly applicable therapeutic paradigm towards pathologies with inflammatory disorders.