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Updated: May 2, 2026

Author Spotlight: PEGASOS Tissue Clearing Technique to Visualize Bone Remodeling
Published on: August 18, 2023
Semaphorin 3A: A new player in bone remodeling
1Department of Orthopedic Surgery; Graduate School; Tokyo Medical and Dental University; Yushima, Bunkyo-ku, Tokyo, Japan; Global Center of Excellence (GCOE) Program; International Research Center for Molecular Science in Tooth and Bone Diseases; Tokyo Medical and Dental University, Tokyo, Japan.
Abstract:
Semaphorin 3A (Sema3A) is a protein identified originally as a diffusible axonal chemorepellent. Sema3A has multifunctional roles in embryonic development, immune regulation, vascularization, and oncogenesis. Bone remodeling consists of two phases: the removal of mineralized bone by osteoclasts and the formation of new bone by osteoblasts, and plays an essential role in skeletal diseases such as osteoporosis. Recent studies have shown that Sema3A is implicated in the regulation of osteoblastgenesis and osteoclastgenesis. Moreover, low bone mass in mice with specific knockout of Sema3A in the neurons indicates that Sema3A regulates bone remodeling indirectly. This review highlights recent advances on our understanding of the role of sema3A as a new player in the regulation of bone remodeling and proposes the potential of sema3A in the diagnosis and therapy of bone diseases.
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