Research progress on the systemic regulatory effects of bone-derived exosomes

Bone is one of the largest organs in the human body, which not only provides protection and movement support for the body, but also secretes bone-derived factors to participate in regulation of body homeostasis. As newly discovered bone-derived factors, bone-derived exosomes have attracted increasing attention. Exosomes are a class of extracellular vesicles with specific sizes. Exosomes secreted by various cells in bone can contain a variety of bioactive substances and be delivered to the target cells to regulate the physiological or pathological processes. Exosomes derived from bone marrow mesenchymal stem cells are involved in the homeostatic regulation and pathological development of multiple systems, while exosomes secreted by osteoblasts and osteoclasts mainly regulate bone metabolism. As mechanical stress responsive cells of bone, exosomes secreted by osteocytes and chondrocytes are involved in regulating the physiological effects caused by mechanical stimulation. In this review, we will elaborate on the exosomes derived from different cells in bone to explore the regulatory effects of bone-derived exosomes on the whole body.