Rapamycin Attenuates Load-Induced Cardiac Hypertrophy in Mice

  • Tetsuo Shioi
    From the Cardiovascular Division, Department of Medicine (T.S., J.R.M., O.T., K.C., W.J.M., S.I.) and Department of Radiology (K.C., W.J.M.), Beth Israel Deaconess Medical Center, and the Department of Cardiology (M.C.S.), Boston Children’s Hospital, Boston, Mass.
  • Julie R. McMullen
    From the Cardiovascular Division, Department of Medicine (T.S., J.R.M., O.T., K.C., W.J.M., S.I.) and Department of Radiology (K.C., W.J.M.), Beth Israel Deaconess Medical Center, and the Department of Cardiology (M.C.S.), Boston Children’s Hospital, Boston, Mass.
  • Oleg Tarnavski
    From the Cardiovascular Division, Department of Medicine (T.S., J.R.M., O.T., K.C., W.J.M., S.I.) and Department of Radiology (K.C., W.J.M.), Beth Israel Deaconess Medical Center, and the Department of Cardiology (M.C.S.), Boston Children’s Hospital, Boston, Mass.
  • Kimber Converso
    From the Cardiovascular Division, Department of Medicine (T.S., J.R.M., O.T., K.C., W.J.M., S.I.) and Department of Radiology (K.C., W.J.M.), Beth Israel Deaconess Medical Center, and the Department of Cardiology (M.C.S.), Boston Children’s Hospital, Boston, Mass.
  • Megan C. Sherwood
    From the Cardiovascular Division, Department of Medicine (T.S., J.R.M., O.T., K.C., W.J.M., S.I.) and Department of Radiology (K.C., W.J.M.), Beth Israel Deaconess Medical Center, and the Department of Cardiology (M.C.S.), Boston Children’s Hospital, Boston, Mass.
  • Warren J. Manning
    From the Cardiovascular Division, Department of Medicine (T.S., J.R.M., O.T., K.C., W.J.M., S.I.) and Department of Radiology (K.C., W.J.M.), Beth Israel Deaconess Medical Center, and the Department of Cardiology (M.C.S.), Boston Children’s Hospital, Boston, Mass.
  • Seigo Izumo
    From the Cardiovascular Division, Department of Medicine (T.S., J.R.M., O.T., K.C., W.J.M., S.I.) and Department of Radiology (K.C., W.J.M.), Beth Israel Deaconess Medical Center, and the Department of Cardiology (M.C.S.), Boston Children’s Hospital, Boston, Mass.

抄録

<jats:p><jats:bold><jats:italic>Background—</jats:italic></jats:bold>Cardiac hypertrophy, or an increase in heart size, is an important risk factor for cardiac morbidity and mortality. The mammalian target of rapamycin (mTOR) is a component of the insulin-phosphoinositide 3-kinase pathway, which is known to play a critical role in the determination of cell, organ, and body size.</jats:p><jats:p><jats:bold><jats:italic>Methods and Results—</jats:italic></jats:bold>To examine the role of mTOR in load-induced cardiac hypertrophy, we administered rapamycin, a specific inhibitor of mTOR, to mice with ascending aortic constriction. Activity of p70 ribosomal S6 kinase 1 (S6K1), an effector of mTOR, was increased by 3.8-fold in the aortic-constricted heart. Pretreatment of mice with 2 mg · kg<jats:sup>−1</jats:sup>· d<jats:sup>−1</jats:sup>of rapamycin completely suppressed S6K1 activation and S6 phosphorylation in response to pressure overload. The heart weight/tibial length ratio of vehicle-treated aortic-banded mice was increased by 34.4±3.6% compared with vehicle-treated sham-operated mice. Rapamycin suppressed the load-induced increase in heart weight by 67%. Attenuation of cardiac hypertrophy by rapamycin was associated with attenuation of the increase in myocyte cell size induced by aortic constriction. Rapamycin did not cause loss of body weight, lethality, or left ventricular dysfunction.</jats:p><jats:p><jats:bold><jats:italic>Conclusions—</jats:italic></jats:bold>mTOR or its target(s) seems to play an important role in load-induced cardiac hypertrophy. Because systemic administration of rapamycin has been used successfully for the treatment of transplant rejection in clinical practice, it may be a useful therapeutic modality to suppress cardiac hypertrophy in patients.</jats:p>

収録刊行物

  • Circulation

    Circulation 107 (12), 1664-1670, 2003-04

    Ovid Technologies (Wolters Kluwer Health)

被引用文献 (10)*注記

もっと見る

関連プロジェクト

もっと見る

詳細情報 詳細情報について

問題の指摘

ページトップへ