Elucidation of pathogenic factor in Streptococcus mutans contributing to the stroke onset

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K10471
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 57080:Social dentistry-related
• Research Institution: Tsurumi University
• Principal Investigator: Murata Takatoshi 鶴見大学, 歯学部, 講師 (10313529)
• Co-Investigator(Kenkyū-buntansha): 花田 信弘 鶴見大学, 歯学部, 教授 (70180916) ; 宮之原 真由 鶴見大学, 歯学部, 学部助手 (70460186)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: Streptococcus mutans / 脳卒中 / コラーゲン結合蛋白

Outline of Final Research Achievements

It has been reported that an association between infection with Streptococcus mutans expressing collagen-binding protein (CNM) and stroke onset. It is possible that the virulence factor that contributes to the onset of stroke is not the cells themselves, but the extracellularly secreted or leaked CNM because of no reports of isolation of S. mutans cells from stroke-affected areas.
CNM is a protein with a molecular weight of 70 kDa that strongly adheres to the cell wall and is present on the surface of the bacterial bodies. However, it has been revealed that CNM detected outside the bacterial bodies has a molecular weight of approximately 100 kDa. Therefore, this suggests the possibility that CNM complexes, which are bound to some unidentified molecules, may contribute to the onset of stroke.

Free Research Field

口腔衛生学

Academic Significance and Societal Importance of the Research Achievements

我が国の疾病分類別医科診療医療費では、脳血管疾患を含む「循環器系の疾患」は最も多く約20%を占めている重大疾病である。そのような社会背景の中、脳血管疾患を含む生活習慣病の発症予防、重症化予防の基本方針として、「歯と口腔の健康」の推進が定められている。
本研究成果は、代表的な口腔病原性細菌であるStreptococcus mutansの脳卒中発症に寄与する病原因子を示唆するものであり、脳卒中発症予防における「歯と口腔の健康」の推進の妥当性を支持する。また、今後の研究展開により、S. mutansによる脳卒中発症メカニズム解明、S. mutansを標的とする脳卒中発症予防法の開発につながる。