Exploration of food functionality of Dioscorea japonica targeting lipid mediator

2014 Fiscal Year Final Research Report

• Project/Area Number: 24500948
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Eating habits, studies on eating habits
• Research Institution: Okayama Prefectural University
• Principal Investigator: TOSHIKO Suzuki-Yamamoto 岡山県立大学, 保健福祉学部, 准教授 (60301313)
• Co-Investigator(Renkei-kenkyūsha): INOUE Hiroyasu 奈良女子大学, 生活環境学部, 教授 (40183743) ; YAMAMOTO Kei 財団法人東京都医学総合研究所, 主席研究員 (30304504) ; KAWAKAMI Yuki 岡山県立大学, 保健福祉学部, 助教 (30453202)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 脂質メディエーター / PGE2 / COX-2 / mPGES-1 / 炎症 / 癌 / 自然薯 / 食品機能性

Outline of Final Research Achievements

In this study, we investigated novel functions of Dioscorea japonica on the related enzymes synthesizing prostaglandin (PG) E2. PGE2 is one of the lipid mediators, and is involved in many pathophysiological conditions such as inflammation and tumorigenesis. Under the conditions, PGE2 is synthesized from arachidonic acid by cyclooxygenase (COX)-2 and microsomal PGE synthase (mPGES)-1. Dioscorea japonica extract (DJE) suppressed COX-2 and mPGES-1 in carcinoma A549 and Caco-2 cells, and inflammatory RAW264 cells. DJE induced cancer cells to apoptosis, and suppressed inflammatory cytokines. In mouse model of squamous cell carcinoma of the skin, Dioscorea japonica inhibited tumor formation, suppressed COX-2 and mPGES-1, and decreased subepidermal eosinophils and neutrophils. These results indicate that Dioscorea japonica may have preventive effects against inflammation and tumorigenesis via suppression of PGE2 synthesis pathway.

Free Research Field

脂質生化学