Dementia and gut microbiota

• Project/Area Number: 16K15132
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Natural medicines
• Research Institution: Osaka City University
• Principal Investigator: TOMIYAMA Takami 大阪市立大学, 大学院医学研究科, 准教授 (10305633)
• Co-Investigator(Renkei-kenkyūsha): UMEDA Tomohiro 大阪市立大学, 大学院医学研究科, 助教 (70549790)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000); Fiscal Year 2017: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2016: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: Gut microbiota / Dementia / Alzheimer's dsease / Antibiotic / Fecal transplantation / Herb extract / Model mouse / Memory / 認知症 / 腸内フローラ / 生薬抽出物 / 生薬

Outline of Final Research Achievements

To investigate possible relationship between dementia and gut microbiota, we examined cognitive function of our model mice (OSK-KI mice) after 1-month oral administration of antibiotics, fecal extracts, and anti-dementia herb extract Ekc-1. Antibiotic treatment and fecal transplantation influenced mouse memory, suggesting cognition is affected by gut microbiota. The beneficial effects of Ekc-1 on memory was partially cancelled by simultaneous antibiotic treatment, implying anti-dementia effects of Ekc-1 is, at least in part, mediated by gut microbiota. We analyzed gut microbiota in our different model mice (APP x tau double Tg mice) after 1-month Ekc-1 oral treatment. We found some differences between Tg and non-Tg mice, and Ekc-1 appeared to shift the balance of microbiota toward non-Tg mice. Subcutaneous administration of Ekc-1 little improved mouse memory. Our findings suggest that gut microbiota affects cognitive function, and its modification could be a treatment for dementia.