Improving effect of a filtrate of soymilk fermented by lactic acid bacteria on non-alcoholic steatohepatitis (NASH)

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05901
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 38050:Food sciences-related
• Research Institution: Tokyo University of Technology
• Principal Investigator: NODAKE Yuichi 東京工科大学, 応用生物学部, 教授 (30332282)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 豆乳の乳酸菌発酵ろ液 / 非アルコール性脂肪性肝炎（NASH）

Outline of Final Research Achievements

A filtrate of soymilk fermented by 16 lactic acid bacteria has been demonstrated to indicate several biological activities. In this study, five-week-old non-alcoholic steatohepatitis (NASH) model mice were fed ad libitum with a high-fat diet supplemented with a freeze-dried powder of the fermented filtrate for 4 weeks. As a result, liver weight, plasma TG level, and NAFLD activity score in the experimental group were lower than that in the control group. Since the suppression of lipid accumulation and infiltration of inflammatory cells were also observed in the experimental group, it was suggested that the fermented filtrate indicated an improving effect on lipid metabolism and NASH symptoms. In addition, it was found that the fermented filtrate partially suppressed some expression level of lipid synthesis genes in hepatocytes and that could be used as a prebiotic to improve gut microbiota.

Free Research Field

生化学、食品科学、スキンケア

Academic Significance and Societal Importance of the Research Achievements

近年、肝疾患と腸内細菌叢との深い関連性が注目されているが、乳酸菌を用いた発酵食品（特にバイオジェニックスに分類される食品）が腸内環境の改善を介してNASHの抑制に関与していることを示唆する報告は未だ十分ではない。本研究で研究対象とした豆乳の乳酸菌発酵ろ液は、調製の最終工程（ろ過）で乳酸菌そのものを除去していることから、腸管との観点からはバイオジェニックスに分類される。したがって、本発酵ろ液が脂質代謝やNASH病態に対する改善作用を有することを強く示唆する今回のデータは、今後の医・食両分野の研究にとって大変意義のあるものであると評価している。