A study of association between enteric bacteria markers and patients with synucleinopathy

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K09711
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Neurology
• Research Institution: Niigata University
• Principal Investigator: Ozawa Tetsutaro 新潟大学, 医歯学総合病院, 特任教授 (10377153)
• Research Collaborator: NISHIZAWA masatoyo
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: シヌクレイノパチー / パーキンソン病 / 嗅覚低下 / 口腔微生物 / 腸内細菌 / 硫化水素 / 自律神経障害

Outline of Final Research Achievements

The aim of this study was to determine whether olfactory disturbance and gastrointestinal symptoms of early stage of Parkinson's disease (PD) were associated with metabolites from enterobacterial flora including oral bacteria. Thirty-five patients with early stage of PD and fourteen age-matched control subjects who had no neurodegenerative diseases were participated in this study. The olfactory disturbance and gastrointestinal symptoms in PD patients were more severe than those in controls. Rate of Helicobacter pylori infection was not different between the two groups. The severity of gastrointestinal symptom was not correlated with breath concentration of hydrogen sulfide that was produced by oral bacteria. In early stage of PD, the severity of olfactory disturbance was significantly correlated with the breath concentration of hydrogen sulfide. Our results suggest that pathogenic mechanism of olfactory disturbance in PD patients is associated with metabolites from oral bacteria.

Free Research Field

神経内科

Academic Significance and Societal Importance of the Research Achievements

パーキンソン病の前駆症状として、嗅覚低下と便秘を含めた消化管機能障害が知られている。本研究では、パーキンソン病の嗅覚低下に口腔微生物により産生された硫化水素がPDの嗅神経障害に関与している可能性が示唆された。硫化水素は高濃度であれば短時間で嗅神経を障害することが知られている。本研究で検出した口腔内の硫化水素は低濃度ではあるが、硫化水素を発する口腔微生物の生息は患者の生活史の大部分におよぶ可能性があり、患者の嗅神経は低濃度硫化水素に長期間曝露された可能性がある。今後は嗅神経における低濃度硫化水素の長期曝露の影響をさらに検討する必要がある。