Omics Profiles of Fecal Microbiota Change in Irritable Bowel Syndrome Patients with Diarrhea and Symptom Exacerbation

2021 Fiscal Year Final Research Report

• Project/Area Number: 17K17584
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: General internal medicine(including psychosomatic medicine); Gastroenterology
• Research Institution: Tohoku University
• Principal Investigator: Tanaka Yukari 東北大学, 医学系研究科, 大学院非常勤講師 (50721453)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Keywords: 過敏性腸症候群 / 腸内細菌 / 口腔細菌 / 縦走オミクス

Outline of Final Research Achievements

Irritable bowel syndrome (IBS) is a disorder of gut-brain interaction. However, the role of gastrointestinal microbiota during IBS symptom exacerbation remains unclear. We tested the hypothesis that the fecal microbial composition are altered during the exacerbation of IBS symptoms. Fecal samples were collected from 43 men with IBS with diarrhea (IBS-D) and 40 healthy control (HC) men. Samples in the IBS-D patients were also collected during symptom exacerbation. The composition of the fecal microbiota was determined by analyzing the 16S rRNA gene and metabolites.
The fecal microbiota during IBS symptom exacerbation exhibited significant differences in the phylogenic pattern and short-chain fatty acid compared to without symptom exacerbation. Although there were no significant differences in the phylogenic pattern of fecal microbiota abundance between HCs and IBS-D patients.Our findings suggest that fecal microbiome are altered in IBS-D patients during exacerbation of symptoms.

Free Research Field

過敏性腸症候群

Academic Significance and Societal Importance of the Research Achievements

今回、IBS患者と健常者間、更にIBSの通常排便時と腹部症状出現時比較により、消化管細菌叢のみならず、短鎖脂肪酸や神経伝達物質代謝の変化を明らかにした。これまで申請者らはIBS患者の大腸伸展刺激時の局所脳活動変化を報告してきた。IBSは中枢神経と消化管神経叢間での双方向の情報伝達関連が示唆されるものの、IBSの腹部症状出現タイミングの予測が困難なため研究手法が限られていた。本研究のように侵襲が少ない細菌叢をターゲットとし、同一被験者について複数回の検体採取、並びに縦走オミクス解析を行うことで、今後IBSの症状出現時の消化管環境メカニズムの解明に寄与できる可能性を示すことができた。