Elucidation of liver disease formation by bacterial species analysis detected in human portal blood

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K08451
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 53010:Gastroenterology-related
• Research Institution: St. Marianna University School of Medicine
• Principal Investigator: Watanabe Tsunamasa 聖マリアンナ医科大学, 医学部, 准教授 (20338528)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 腸内細菌叢 / 肝疾患 / 門脈血

Outline of Final Research Achievements

To find a scientific basis for a new treatment strategy for liver disease from the viewpoint of the intestinal environment, a total of 28 cases of human portal vein blood were collected by a unique method. Furthermore, we performed intestinal flora metagenomic analysis by next-generation sequencing, including feces and portal vein blood collected from the same individual at the same time. The results revealed that bacterial DNA was detected in the portal blood flow in about half of the cases, and that the bacterial flora detected in the portal blood and feces in the same case was not the equal. Even for the same liver disease, the bacterial species detected in the portal vein blood differed from each case, and a consistent tendency could not be obtained and a clear association with the disease could not be found.

Free Research Field

肝臓

Academic Significance and Societal Importance of the Research Achievements

近年、増加傾向にあるアルコール性肝疾患や非アルコール性脂肪性肝炎において、肝病態進展と腸内細菌叢の関連が指摘されているが、ヒトにおいて腸管粘膜を通過し門脈を通って肝臓に流入する細菌について検討した報告は少なく、今回独自の方法により採取した門脈血を用いて腸内細菌叢メタゲノム解析を試みた。肝疾患患者の約半数で閉鎖系の門脈血流に細菌が流入している可能性を見出したが、個体差が大きいことも明らかとなった。今後は、肝疾患患者の腸内細菌叢の改変による治療介入の可能性について、さらなる検討が必要と考えられた。