Isolation of drugs which rescue insulin resistance by activating GLUT4 transport activity.

2012 Fiscal Year Final Research Report

• Project/Area Number: 23658222
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Applied animal science
• Research Institution: The University of Tokyo
• Principal Investigator: SHIN-ICHIRO Takahashi 東京大学, 大学院・農学生命科学研究科, 准教授 (00197146)
• Project Period (FY): 2011 – 2012
• Keywords: 糖輸送体(GLUT)4 / 糖取り込み / インスリン / 成長ホルモン / インスリン抵抗性 / 脂肪細胞

Research Abstract

We have reported that chronic GH pretreatment inhibited insulin-induced glucose uptake without affecting insulin-induced GLUT4 translocation. This study was undertaken to identify Akt substrates and GLUT4 postranslational modification that regulate GLUT4 transport activity. In addition, in order to rescue insulin resistance we searched for the small molecular chemicals and antibodies that modulate GLUT4 transport activity.At first, we succeeded to isolate the Akt substrates, AS47, whose insulin-inducedphosphorylation was suppressed by GH pretreatment. Knockdown of AS47 inhibited insulin-induced glucose uptake without affecting GLUT4 translocation, suggesting that AS47 plays important roles in GLUT4 transport activity.Next, we searched for posttranslational modification motif in a GLUT4 molecule. GLUT4 was site-directed mutagenized in some modification sites and these mutants were transfected into HEK293 cell. And then glucose uptake was measured. Mutation at the phosphorylation site of GLUT4 (GLUT4-P) significantly enhanced glucose transport activity, suggesting that phosphorylation impaired GLUT4 transport activity. Moreover, we have already succeeded to isolate antibodies, which recognize GLUT4 extracellular domain.In this study we succeeded to identify the Akt substrate and GLUT4 posttranslational modification, which play important roles in GLUT4 transport activity. Chemicals or antibodies, which interact with the Akt substrate and GLUT4 could be candidates tocure insulin resistance.

Research Products

• [Journal Article] AP-1 complex regulates intracellular localization of insulin receptor substrate-1 required for insulin-like growth factor-I-dependent cell proliferation (2013)
  • Author(s): Yoneyama Y, Matsuo M, Take K, Kabuta T, Chida K, Hakuno F, Takahashi SI
  • Journal Title: Mol. Cell. Biol Volume: 33 Pages: 1991-2003
  • DOI: doi:10.1128/MCB.01394-12.
• [Journal Article] Phosphatidylinositol 3-kinase (PI3K) activity bound to insulin-like growth factor-I (IGF-I) receptor, which is continuously sustained by IGF-I stimulation, is required forIGF-I-induced cell proliferation (2013)
  • Author(s): Fukushima T, Nakamura Y, Yamanaka D,Shibano T, Chida K, Minami S, Asano T, Hakuno F, Takahashi SI
  • Journal Title: J. Biol. Chem Volume: 287 Pages: 29713-29721
  • DOI: doi:10.1074/jbc.M112.393074.
• [Journal Article] Insulin/IGF stimulation abrogates an association between a deubiquitinating enzyme USP7 and insulin receptor substrates (IRSs) followed by proteasomal degradation of IRSs. Biochem (2012)
  • Author(s): Yoshihara H, Fukushima T, Hakuno F, Saeki Y, Tanaka K, Ito A, Yoshida M, Natsume T, Asano T, Chida K, Girnita L, Takahashi SI
  • Journal Title: Biophys. Res. Commun Volume: 423 Pages: 122-127
  • DOI: doi:10.1016/j.bbrc.2012.05.093.
• [Journal Article] Itoh H. Novel repressor regulates insulin sensitivity through interaction with Foxo1 (2012)
  • Author(s): Nakae J, Cao Y, Hakuno F, Takemori H, Kawano Y, Sekioka R, Abe T, Kiyonari H, Tanaka T, Sakai J, Takahashi SI
  • Journal Title: EMBO J Volume: 31 Pages: 2275-2295
  • DOI: doi:10.1038/emboj.2012.97.
• [Journal Article] Phosphatidylinositol 3-kinase-binding protein, PI3KAP/XB130, is required for cAMP-induced amplification of IGF mitogenic activity in FRTL-5 thyroid cells (2012)
  • Author(s): Yamanaka D, Akama T, Fukushima T, Nedachi T, Kawasaki C, Chida K, Minami S, Suzuki K, Hakuno F, Takahashi SI
  • Journal Title: Mol. Endocrinol Volume: 26 Pages: 1043-1055
  • DOI: doi:10.1210/me.2011-1349.
• [Presentation] GLUT4の糖膜透過能活性化におけるGLUT4セリン488番目のリン酸化の役割 (2012)
  • Author(s): 久保真実子、笠原浩平、曽根芽里、千田和広、伯野史彦、高橋伸一郎
  • Organizer: 第35回日本分子生物学会年会
  • Place of Presentation: 福岡国際会議場
  • Year and Date: 2012-12-14
• [Presentation] Diacylglycerol kinase ζ, negatively modulated GLUT4 translocation in 3T3-L1 adipocytes (2012)
  • Author(s): Hakuno F, Ando Y, Kakino M, Fujimoto H, Chida K, Takahashi SI
  • Organizer: 6^th GRS-IGF
  • Place of Presentation: Munich, Germany.
  • Year and Date: 2012-10-19
• [Presentation] インスリン様ペプチドの進化と生理的異議 (2011)
  • Author(s): 高橋伸一郎
  • Organizer: 第29回千駄木内分泌懇話会
  • Place of Presentation: 東京(招待講演)
  • Year and Date: 2011-10-20
• [Presentation] インスリン様成長因子とインスリンの単独プレイと連携プレイ (2011)
  • Author(s): 高橋伸一郎
  • Organizer: 内分泌代謝学サマーセミナー
  • Place of Presentation: 仙台(招待講演)
  • Year and Date: 2011-07-07
• [Remarks]
  • URL: http://endo.ar.a.u-tokyo.ac.jp/index0.html