The development of medicine accelerating bone formation to apply artificial exosomes

• Project/Area Number: 18K17015
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 57010:Oral biological science-related
• Research Institution: Tokyo Medical and Dental University (2018, 2021); Saitama Medical University (2019-2020)
• Principal Investigator: Sugamori Yasutaka 東京医科歯科大学, 歯学部, 非常勤講師 (60814902)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2020: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2019: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000); Fiscal Year 2018: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
• Keywords: 骨形成促進剤 / RANKL / RANK / 分泌小胞 / エクソソーム / 人工エクソソーム / 骨芽細胞 / 破骨細胞

Outline of Final Research Achievements

Towards the development of artificial exosomes expressing RANK, which induce bone formation signal, we incorporated RANK lacking intracellular domain (minimal RANK) into exosomes made from phospholipid, DOPC. we investigated the function of　exosomes expressing minimal RANK, using experiments in which bone marrow cells were stimulated with M-CSF and soluble RANKL to induce osteoclasts. The results suggest that the formation of oseteoclasts was suppressed depending on the　concentration of DOPC, rather than the presence or absence of RANK expression, and the RANKL-binding ability of RANK expressed in minimal RANK exosomes was not confirmed.

Academic Significance and Societal Importance of the Research Achievements

近年、破骨細胞が分泌するRANKを発現した膜小胞に骨形成能がある事が見出されたことから、RANK発現した人工分エクソソームの創製は新たな骨形成促進剤の候補になり得る。
本研究では、RANKL結合能を有するRANK発現エクソソームの開発には至らなかったが、DOPCは構成材料として不適切であり、別のリン脂質を用いる必要があることが分かった。また、生理的に活性化したRANKは三量体化することが知られている。その為、機能的なRANKL-RANK結合を誘導するにはエクソソーム上に三量体構造を模したRANKを発現させる必要があると考える。以上が今後の研究の方向性として見出されたことは学術的意義がある。

Research Products

• [Journal Article] The Effects of Receptor Activator of NF-kappa B Ligand-Binding Peptides on Bone Resorption and Bone Formation (2021)
  • Author(s): Rashed Fatma, Kamijyo Shingo, Shimizu Yuri, Hirohashi Yuna, Khan Masud, Sugamori Yasutaka, Murali Ramachandran, Aoki Kazuhiro
  • Journal Title: FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY Volume: 9 Pages: 648084-648084
  • DOI: 10.3389/fcell.2021.648084
  • Peer Reviewed / Open Access
• [Journal Article] Bone phenotype in melanocortin 2 receptor-deficient mice (2020)
  • Author(s): Sato Tsuyoshi、Iwata Takanori、Usui Michihiko、Kokabu Shoichiro、Sugamori Yasutaka、Takaku Yuki、Kobayashi Takashi、Ito Ko、Matsumoto Masahito、Takeda Shu、Xu Ren、Chida Dai
  • Journal Title: Bone Reports Volume: 13 Pages: 100713-100713
  • DOI: 10.1016/j.bonr.2020.100713
  • Peer Reviewed / Open Access
• [Presentation] 膜型RANKLを標的にした骨形成促進薬の開発 (2020)
  • Author(s): 青木和広、清水優里、Lu Wei、廣橋優奈、曽根絵梨、池淵祐樹、Masud Khan、Fatma Rashed、田村幸彦、菅森泰隆、寺坂尚紘、宇田川信之、依田哲也、本間雅、菅裕明
  • Organizer: 第62回歯科基礎医学会学術大会