Ischemic survival and constitutively active autophagy in self-beating atypically-shaped cardiomyocytes (ACMs): characterization of a new subpopulation of heart cells.
Atypically-shaped cardiomyocytes (ACMs) are a new subpopulation of spontaneously beating heart cells with a peculiar morphology identified within a culture of cardiac myocyte-depleted fraction (CMDF) cells obtained from adult mouse heart. ACMs originate from small cells in CMDF and grow in size and start beating within ~3 days culture without appreciable proliferation or express stem cell marker proteins, but stay in the heart until elderly stages. However, the characteristics of ACMs are largely unclear. The present study examined whether pre-exposure of CMDF cells to severe ischemia abolished the ability of ACMs to develop into beating cells. Of ACMs that underwent ischemia, ~50 % grew in size, changed the morphology, and started beating during the subsequent culture under normoxia. ACMs displayed constitutively active autophagy during the culture. The results suggest the possibility that the development of beating ACMs could occur in injured heart, even if the surviving cell population is small.
Department of Physiology, Shiga University of Medical Science, Otsu, Shiga, 520-2192, Japan. m_omatsu@belle.shiga-med.ac.jp.
Mariko
M
Omatsu-Kanbe
Department of Physiology, Shiga University of Medical Science, Otsu, Shiga, 520-2192, Japan.
Hiroshi
H
Matsuura
D000818:Animals; D001343:Autophagy / Q000187:drug effects / Q000502:physiology*; D000071192:Autophagy-Related Protein 12; D002118:Calcium / Q000378:metabolism; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006352:Heart Ventricles / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D018942:Macrolides / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D017202:Myocardial Ischemia / Q000378:metabolism / Q000473:pathology*; D009206:Myocardium / Q000166:cytology* / Q000378:metabolism / Q000473:pathology; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D011506:Proteins / Q000378:metabolism
C491971:Atg12 protein, mouse; D000071192:Autophagy-Related Protein 12; D018942:Macrolides; C480860:Map1lc3b protein, mouse; D008869:Microtubule-Associated Proteins; D011506:Proteins; C057620:bafilomycin A; D002118:Calcium