Investigation of functional materials in watercress and their mechanisms of anti-inflammatory activity

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K14013
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 08030:Family and consumer sciences, and culture and living-related
• Research Institution: Osaka Prefecture University
• Principal Investigator: Nakaya Makoto 大阪府立大学, 研究推進機構, 客員研究員 (90736886)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: クレソン / ジフェネチルウレア / 脂質メディエーター / 可溶性エポキシヒドロラーゼ阻害 / 機能性成分 / 抗炎症作用 / イソチオシアネート

Outline of Final Research Achievements

Watercress (Nasturtium officinale) is a traditional food plant in Europe that has beneficial effects for human health and is becoming popular in Japan as a healthy vegetable. We found that phenethyl isothiocyanate (PE-ITC) and 1,3-diphenethylurea (PE-UR) in watercress have human soluble epoxide hydrolase (sEH) inhibitory activity and anti-inflammatory effects in mice. sEH is located in the CYP pathway and plays an important role in regulating inflammation. Eicosanoids derived from arachidonic acid had anti-inflammatory effects through not only the CYP pathway but also the COX and LOX pathways in PE-UR-fed mice. We also found that PE-ITC causes damage to gut microbiota in mice but PE-UR does not. PE-ITC is probably not good as an anti-inflammatory, considering that many studies have linked the gut microbiota to suppressing inflammation. We suspect that PE-UR is the main functional material contributing to the beneficial effects of watercress.

Free Research Field

機能性食品学

Academic Significance and Societal Importance of the Research Achievements

クレソンはヨーロッパにおいて伝統的に健康増進目的で食されているものの、抗炎症効果を齎す機能性成分とその作用機序に科学的根拠が付与されていない。一般にアブラナ科植物の機能性はイソチオシアネート類に寄るとされるが、本研究から明らかなように、強い殺菌効果による腸内菌叢への悪影響など抗炎症効果の主因とするには説明できない部分が多い。我々はPE-URが抗炎症効果の主因であることを示唆する知見を得たが、この成果は機能性食品学の発展に貢献する。また、明確な科学的根拠を添えて、食品がもつ健康増進効果を示すことにより、伝統的な食品の価値を改めて社会に発信することができる。これは食と農を豊かにする一助となる。