Basic research of the sex difference in tongue neuropathic pain caused by lingual nerve injury in mice

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K07746
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 51030:Pathophysiologic neuroscience-related
• Research Institution: Nihon University
• Principal Investigator: TSUBOI Yoshiyuki 日本大学, 歯学部, 講師 (50246906)
• Co-Investigator(Kenkyū-buntansha): 浅野 正岳 日本大学, 歯学部, 教授 (10231896) ; 三枝 禎 日本大学, 松戸歯学部, 教授 (50277456)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 性差 / 舌痛症

Outline of Final Research Achievements

The purpose of this study is to assess the sex difference in the role in immune cells in the central nervous mechanism in tongue mechanical allodynia and heat hyperalgesia after lingual nerve injury (LNI) in mice. From day 1 to day 9 after LNI, HWRT to mechanical or heat stimulation was significantly decreased in male and female mice. After minocycline administration, the decrease of HWRT to mechanical or heat stimulation by LNI was suppressed only in male mice. On the other hand, after pioglitazone administration, the decrease of HWRT to mechanical or heat stimulation by LNI was suppressed only in female mice. These results suggest that sex difference in tongue neuropathic pain after lingual nerve injury involves the difference in immune cells expressing in the central nervous system and regulating the ascending nociceptive pathway.

Free Research Field

神経生理学

Academic Significance and Societal Importance of the Research Achievements

本研究では、神経障害性モデル動物を使用して，延髄内の免疫反応の違いが，疼痛様行動発現の性差に関与しているかを調べることにより，舌神経損傷後の舌神経障害性疼痛の性差には，上行性痛覚伝達系の興奮性を調節する免疫細胞の相違が関与することが示唆できた。このことにより，延髄内の免疫反応の違いにターゲットにした性差を加味した新規の治療に応用できる知見が得られた。