Analysis of the recovery process of the taste receptor mechanisms after lingual nerve injury

• Project/Area Number: 25463132
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Surgical dentistry
• Research Institution: Niigata University
• Principal Investigator: YOSHIKAWA HIROYUKI 新潟大学, 医歯学総合病院, 助教 (20547575)
• Co-Investigator(Kenkyū-buntansha): 瀬尾 憲司 新潟大学, 医歯学系, 教授 (40242440) ; 照光 真 北海道医療大学, 歯学部, 教授 (60401767)
• Project Period (FY): 2013-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000); Fiscal Year 2017: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2016: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2015: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2014: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2013: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
• Keywords: 舌神経障害 / BDNF / 味蕾 / 神経再生 / ＢＤＮＦ / 神経損傷 / 舌神経 / 舌神経損傷 / 末梢神経再生

Outline of Final Research Achievements

In this study, changes in the tongue papilla, including the taste buds, caused by lingual nerve injury, were examined using clinical and model animals. Imaging of injured nerves using 3-dimensional volume rendering MR neurography showed low relevance between sensation and taste, tongue mucosal atrophy, and injured nerve morphology. In the nerve injury model, BDNF mRNA expression was transiently elevated after nerve injury, and suppressing its activity did not exhibit an allodynia-like response. In the neural repair process, suppression of the BDNF activity did not form a neuroma, instead induced axonal regeneration. Functional regeneration was not inhibited. As the taste receptors T1R1 and T1R3 mRNA expression tended to increase even after tongue nerve transection, the relationship between the taste after injury and papillary atrophy was considered not to be the healing state alone, but to the difference in the expression level of taste receptors.

Academic Significance and Societal Importance of the Research Achievements

末梢神経が損傷した後の修復にはBDNFが関与しており、修復された神経の形態・機能に影響を与える。ヒトで損傷神経を画像解析と異常感覚の重症度、味覚および舌乳頭萎縮の関係を検討すると、神経の形態異常と症状の関連性は低いことが示された。 一方、動物実験で味覚受容体T1RファミリーとBDNFの発現の解析結果から、味覚回復についても修復神経の形態よりも味覚受容体の発現が関わっている可能性がある。これらより舌神経損傷に対する機能的回復を目指した治療には、BDNFなどの薬物による治療が役立つ可能性がある。

Research Products

• [Journal Article] Peripheral Brain-Derived Neurotrophic Factor Modulates Regeneration Following Inferior Alveolar Nerve Injury in Rats (2016)
  • Author(s): Yoshikawa H, Yamada Y, Kurose M, Yamamura K, Maeda T, Seo K
  • Journal Title: J Oral Facial Pain Headache Volume: 30(4) Pages: 346-354
  • DOI: 10.11607/ofph.1651
  • Peer Reviewed
• [Presentation] 舌神経障害における舌乳頭萎縮に関連する異常所見の検討 (2017)
  • Author(s): 吉川博之、照光真、須田有紀子、田中裕、弦巻立、倉田行伸、佐藤由美子、金丸博子、小玉由記、瀬尾憲司
  • Organizer: 第45回日本歯科麻酔学会総会・学術集会
• [Presentation] Functional analysis of the regenerated inferior alveolar nerve after local administration of anti-BDNF antibody to the transected site. (2014)
  • Author(s): Hiroyuki Yoshikawa, Yessenia Maria Valverde, Takeyasu Maeda, Masayuki Kurose, Kensuke Yamamura, Kenji Seo
  • Organizer: 44th Annual Meeting of the Society for Neuroscience
  • Place of Presentation: Walter E. Washington Convention Center(Washington, DC, U.S.)
  • Year and Date: 2014-11-15 – 2014-11-19
• [Presentation] 神経損傷によるニューロトロフィンの変化を導くメカニズムについて (2013)
  • Author(s): 吉川博之、弦巻立、瀬尾憲司
  • Organizer: 日本歯科麻酔学会総会・学術集会
  • Place of Presentation: 新横浜国際ホテル