Magnesium Ammonium Phosphate Composite Cell-Laden Hydrogel Promotes Osteogenesis and Angiogenesis In Vitro
Chang Liu1, Guangzheng Yang1, Mingliang Zhou1
1Department of Prosthodontics, Shanghai Engineering Research Center of Advanced Dental Technology and Materials, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, 639 Zhizaoju Road, Shanghai 200011, China.
Abstract:
Injectable hydrogels provide an effective strategy for minimally invasive treatment on irregular bony defects in the maxillofacial region. To improve the osteoinduction of gelatin methacrylate (GelMA), we fabricated a three-dimensional (3D) culture system based on the incorporation of magnesium ammonium phosphate hexahydrate (struvite) into GelMA. The optimal concentration of struvite was investigated using the struvite extracts, and 500 μg mL-1 was found to be the most suitable concentration for the osteogenesis of dental pulp stem cells (DPSCs) and angiogenesis of human umbilical vein endothelial cells (HUVECs). We prepared the GelMA composite (MgP) with 500 μg mL-1 struvite. Struvite did not affect the cross-linking of GelMA and released Mg2+ during degradation. The cell delivery system using MgP improved the laden-cell viability, upregulated the expression of osteogenic and angiogenic-differentiation-related genes, and promoted cell migration. Overall, the modifications made to the GelMA in this study improved osteoinduction and demonstrated great potential for application in vascularized bone tissue regeneration.
