Immunomodulatory effects of non-digestible polysaccharides- a focus on their relationships to luminal environments and gut permeability

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K07790
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Food science
• Research Institution: Shizuoka University
• Principal Investigator: Hino Shingo 静岡大学, 農学部, 准教授 (70547025)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: フラクトオリゴ糖 / 腸内細菌叢 / 腸管免疫 / IgA / ラット

Outline of Final Research Achievements

Relationships between immune parameters and the environmental factors were examined in the cecum of rats fed the diet containing fructooligosaccharides. Mucosal inflammation was involved in the IgA secretion promoting effect observed in the early stage ofingestion of the semi-purified diet containing fructooligosaccharides, and the mucin layer was disrupted in the cecum. On the other hand, these series of responses were all canceled during long-term intake and non-purified feed intake. In addition, a series of responses was considered to be induced by changes in the intestinal environment such as the accumulation of lactic acid and the accompanying drastic pH decrease.

Free Research Field

栄養化学

Academic Significance and Societal Importance of the Research Achievements

フラクトオリゴ糖をはじめとする難消化性糖類の摂取は動物実験において免疫調節作用を示すことが報告されており，ヒトでの有用性についても研究が進められている。しかしながら，その作用機序は明確になっていない。本研究からフラクトオリゴ糖の免疫調節作用は，急速な発酵に伴う腸内環境の変化が軽度な粘膜炎症が関与することが明らかとなった。一方で，これらの応答は,長期摂取時やヒトの食事に比較的その物性等が近い非精製飼料では観察されないことが明らかとなった。以上から，難消化性糖類の摂取効果については，その摂取方法や添加する食事の種類を考慮して摂取する必要があると考えられた。