Development of a novel therapeutic approach for burning mouth syndrome using GABAA subunit agonists.

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K10171
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 57060:Surgical dentistry-related
• Research Institution: Nihon University
• Principal Investigator: NOMA Noboru 日本大学, 歯学部, 教授 (70386100)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 口腔灼熱痛症候群 / 口腔顔面痛 / 味覚

Outline of Final Research Achievements

Burning Mouth Syndrome (BMS) is a chronic pain disorder primarily affecting the tongue, with unclear etiology and established treatment methods. Research using quantitative sensory testing has identified dysfunction in the chorda tympani nerve, suggesting involvement of the central nervous system, as evidenced by elevated thresholds and occurrence of symptoms on both sides even with unilateral dysfunction. This study aimed to evaluate the use of Central Sensitization Inventory (CSI) scores at the site of burning sensation as a diagnostic test to differentiate between BMS and Secondary Burning Mouth Syndrome (SBMS), investigate the relationship between CSI scores, taste thresholds, and pain duration varying by disease (BMS vs SBMS). Finally, it examined the pain thresholds and anatomical changes in the tongues of OVX rats to elucidate a portion of the pathogenesis of BMS.

Free Research Field

口腔内科学分野

Academic Significance and Societal Importance of the Research Achievements

本研究では一次性BMSのCSIスコアが二次性BMSと比較して高くなることから簡易的に鑑別診断が可能となり口腔顔面痛研究においてインパクトが大きい。一次性BMSの病脳期間が長い程、また中枢性感作が強い程、味覚閾値が低下した。このことから鼓索神経の入力が低下して三叉神経を介して痛み情報伝達の脱抑制が生じている可能性が示された。また動物実験において卵巣摘出ラットにおいて機械刺激に対する舌の痛覚過敏が誘発され、舌粘膜上皮の神経線維が減少した。GABAA受容体のサブユニット構成の変化が神経障害性疼痛様の症状を惹起した可能性を示唆する。BMSの新規治療開発の一助になることが考えられる。