Role of mitochondrial permeability transition in necroptosis of the cardiomyocyte

2016 Fiscal Year Annual Research Report

• Project/Area Number: 26461133
• Research Institution: Sapporo Medical University
• Principal Investigator: 三浦 哲嗣 札幌医科大学, 医学部, 教授 (90199951)
• Co-Investigator(Kenkyū-buntansha): 三木 隆幸 札幌医科大学, 医学部, 准教授 (00336405) ; 丹野 雅也 札幌医科大学, 医学部, 講師 (00398322)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: necroptosis / autophagy / cell death

Outline of Annual Research Achievements

TNF-alphaとカスパーゼ阻害薬(z-VAD)を併用することにより誘導した心筋細胞のネクロプトーシスに、RIP1-p62結合によるオートファジーの阻害が関与することを前年度まで明らかにした。その結果を基に、RIP1-p62結合がオートファジーを抑制する機序について、GFP-RFP-LC3 tandem constructのトランスフェクションによるautophagosome, autolysosomeの定量によって解析した。その結果、RIP1-p62結合の亢進は、autophagosome形成を抑制せず、autophagosomeとlysosomeの融合によるautolysosome形成を阻害することと観察した。この所見と一致して、autophagosome形成を制御するシグナルであるPI3K-Akt-p70s6KシグナルやAMPK-ULK1シグナルには、TNF-alpha＋z-VADによる変化は見られなかった。また、lyosome内のpHもTNF-alpha＋z-VAD処理による影響を受けなかった。また、Atg5のノックアウトによってもTNF-alpha＋z-VADによるネクロプトーシスには変化がみられないことから、腫瘍細胞のネクロプトーシスとは異なり、心筋細胞では初期のautophagosomal membraneがネクロプトーシスシグナルのscaffoldにはなっていないことが示唆された。
Autolysosomeにおけるアダプター蛋白であるp62の減少がautophagosomeとlyosomeとの癒合抑制をもたらす機序について、今後さらに解析する予定である。

Research Products

• [Journal Article] Insufficient activation of Akt upon reperfusion because of its novel modification by reduced PP2A-B55alpha contributes to enlargement of infarct size by chronic kidney disease. (2017)
  • Author(s): Toshiyuki Tobisawa*, Toshiyuki Yano*, Masaya Tanno, Takayuki Miki, Atsushi Kuno, Yukishige Kimura, Satoko Ishikawa, Hidemichi Kouzu, Keitaro Nishizawa, Hideaki Yoshida, Tetsuji Miura
  • Journal Title: Basic Research in Cardiology Volume: 112 Pages: 31
  • DOI: DOI 10.1007/s00395-017-0621-6
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Chronic Treatment With an Erythropoietin Receptor Ligand Prevents Chronic Kidney Disease-Induced Enlargement of Myocardial Infarct Size. (2016)
  • Author(s): Nishizawa K, Yano T, Tanno M, Miki T, Kuno A, Tobisawa T, Ogasawara M, Muratsubaki S, Ohno K, Ishikawa S, Miura T.
  • Journal Title: Hypertension Volume: 68 Pages: 697-706
  • DOI: 10.1161/HYPERTENSIONAHA.116.07480
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] From basic mechanisms to clinical applications in heart protection, new players in cardiovascular diseases and cardiac theranostics: meeting report from the third international symposium on "New frontiers in cardiovascular research". (2016)
  • Author(s): Cabrera-Fuentes HA, Aragones J, Bernhagen J, Miura T, et al.
  • Journal Title: Basic Research in Cardiology Volume: 111 Pages: 69
  • DOI: 10.1007/s00395-016-0586-x
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Ischaemic conditioning and targeting reperfusion injury: a 30 year voyage of discovery. (2016)
  • Author(s): Hausenloy DJ, Barrabes JA, Davidson SM, Di Lisa F, Downey J, Miura T, et al.
  • Journal Title: Basic Research in Cardiology Volume: 111 Pages: 70
  • DOI: 10.1007/s00395-016-0588-8
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Sequestration of p62 by RIP1 promotes necroptosis through suppression of autophagic flux in cardiomyocytes; a novel cross-talk between autophagy and necroptosis (2016)
  • Author(s): Yano T, Ogasawara M, Miki T, Tanno M, Kuno A, Ohno K, Nishizawa K, Owada W, Mizuno M, Suwawara H, Tatekoshi Y, Nakata K, Ishikawa S, Miura T
  • Organizer: European Society of Cardiology Congress 2016
  • Place of Presentation: Rome, Italy
  • Year and Date: 2016-08-27 – 2016-08-31
  • Int'l Joint Research
• [Presentation] Diabetes and Cardioprotection. (2016)
  • Author(s): Miura T
  • Organizer: Ischaemic conditioning and targeting reperfusion injury: a 30 year voyage of discovery,
  • Place of Presentation: Barcelona, Spain
  • Year and Date: 2016-05-12 – 2016-05-13
  • Int'l Joint Research / Invited
• [Presentation] Role of mitochondria in cell death. The mPTP and its regulatory kinases in cardioprotection. (2016)
  • Author(s): Miura T
  • Organizer: 2016 XXII ISHR World Congress
  • Place of Presentation: Buenos Aires, Argentina
  • Year and Date: 2016-04-18 – 2016-04-21
  • Int'l Joint Research / Invited