The mechanisms by which protein malnutrition increases circulating adiponectin levels in rats

• Project/Area Number: 25850095
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Food science
• Research Institution: Nippon Medical School
• Principal Investigator: Toyoshima Yuka 日本医科大学, 付置研究所, 講師 (70516070)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000); Fiscal Year 2015: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2014: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2013: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
• Keywords: アディポネクチン / 低タンパク質栄養 / 脂肪細胞 / 低タンパク質食 / インスリン / インスリン様成長因子 / タンパク質栄養 / エネルギー消費 / インスリンシグナル / 耐糖能 / アミノ酸

Outline of Final Research Achievements

Adiponectin is a protein that is mainly secreted from adipocytes and exhibits an antidiabetic property, which enhances insulin action. Our previous studies showed that protein malnutrition caused increases in circulating adiponectin levels in growing rats. In this study, we found that the enhancement of adiponectin secretion from adipocytes and/or the suppression of its degradation in the blood result in the elevation of circulating adiponectin levels in protein-malnourished rats. Furthermore, it was suggested that lower circulating insulin and insulin-like growth factor-1 contribute to enhance adiponectin secretion from adipocytes under protein malnutrition.

Research Products

• [Journal Article] Tissue-specific effects of protein malnutrition on insulin signaling pathway and lipid accumulation in growing rats (2014)
  • Author(s): Yuka Toyoshima, Reiko Tokita, Yusuke Taguchi, Narumi Akiyama-Akanishi, Asako Takenaka, Hisanori Kato, Kazuhiro Chida, Fumihiko Hakuno, Shiro Minami, Shin-Ichiro Takahashi
  • Journal Title: Endocrine Journal Volume: 61 Issue: 5 Pages: 499-512
  • DOI: 10.1507/endocrj.EJ13-0514
  • NAID: 130004443967
  • ISSN: 0918-8959, 1348-4540
  • Peer Reviewed
• [Journal Article] Insulin injection restored increased insulin receptor substrate (IRS)-2 protein during short-term protein restriction but did not affect reduced insulin-like growth factor (IGF)-I mRNA or increased triglyceride accumulation in the liver of rats. (2014)
  • Author(s): Yori Ozaki, Tomoya Takeda, Narumi Akanishi, Fumihiko Hakuno, Yuka Toyoshima, Shin-Ichiro Takahashi & Asako Takenaka
  • Journal Title: Bioscience, Biotechnology, and Biochemistry Volume: - Issue: 1 Pages: 130-138
  • DOI: 10.1080/09168451.2014.877825
  • Peer Reviewed
• [Presentation] Insulin-induced acetyl-CoA carboxylase alpha is responsible for triglyceride accumulation in primary hepatocytes of low protein diet-fed rats. (2015)
  • Author(s): Taguchi Y, Toyoshima Y, Tokita R, Kato H, Takahashi S, Minami S
  • Organizer: 12th Asian Congress of Nutrition
  • Place of Presentation: Yokohama, JAPAN
  • Year and Date: 2015-05-14
  • Int'l Joint Research
• [Presentation] Protein malnutrition increases the amount and phosphorylation of 4E-binding protein 1 (4E-BP1) to accumulate lipid in rat liver. (2015)
  • Author(s): Toyoshima Y, Tokita R, Taguchi Y, Yoshizawa F, Takahashi S, Kato H, Minami S
  • Organizer: 12th Asian Congress of Nutrition
  • Place of Presentation: Yokohama, JAPAN
  • Year and Date: 2015-05-14
  • Int'l Joint Research
• [Presentation] 低タンパク質栄養状態におけるエネルギー消費量の亢進は血中アディポネクチン量の増加を介して起こる (2014)
  • Author(s): 豊島由香、時田玲子、田口雄亮、高橋伸一郎、加藤久典、南史朗
  • Organizer: 第8回アミノ酸学会学術集会
  • Place of Presentation: 東京
  • Year and Date: 2014-11-09
• [Presentation] 低タンパク質栄養による血中アディポネクチン増加機構の解析 (2013)
  • Author(s): 豊島由香、時田玲子、田口雄亮、高橋伸一郎、加藤久典、南史朗
  • Organizer: 日本アミノ酸学会第7回学術大会
  • Place of Presentation: 熊本
• [Presentation] 低タンパク質食給餌ラットから調製した単離肝細胞におけるインスリンシグナル (2013)
  • Author(s): 田口雄亮、豊島由香、時田玲子、加藤久典、高橋伸一郎、南史朗
  • Organizer: 第67回日本栄養・食糧学会大会
  • Place of Presentation: 名古屋
• [Remarks] 日本医科大学先端医学研究所
  • URL: http://home.nms.ac.jp/ig/index.html