The bone microenvironment: new insights into the role of stem cells and cell communication in bone regeneration

Mesenchymal stem cells (MSCs) play a crucial role in bone formation and remodeling. Intrinsic genetic factors and extrinsic environmental cues regulate their differentiation into osteoblasts. Within the bone microenvironment, a complex network of biochemical and biomechanical signals orchestrates bone homeostasis and regeneration. In addition, the crosstalk among MSCs, immune cells, and neighboring cells—mediated by extracellular vesicles and non-coding RNAs (such as circular RNAs and micro RNAs) —profoundly influences osteogenic differentiation and bone remodeling. Recent studies have explored specific signaling pathways that contribute to effective bone regeneration, highlighting the potential of manipulating the bone microenvironment to enhance MSC functionality. The integration of advanced biomaterials, gene editing techniques, and controlled delivery systems is paving the way for more targeted and efficient regenerative therapies. Furthermore, artificial intelligence could improve bone tissue engineering, optimize biomaterial design, and enable personalized treatment strategies. This review explores the latest advancements in bone regeneration, emphasizing the intricate interplay among stem cells, immune cells, and signaling molecules. By providing a comprehensive overview of these mechanisms and their clinical implications, we aim to shed light on future research directions in this rapidly evolving field.