RT Journal Article SR Electronic T1 Sympathetic nerve activity promotes cardiomyocyte cell-cycle arrest and binucleation JF bioRxiv FD Cold Spring Harbor Laboratory SP 124347 DO 10.1101/124347 A1 Li Chen A1 Alexander Y. Payumo A1 Kentaro Hirose A1 Rachel B. Bigley A1 Jonathan Lovas A1 Rejji Kuruvilla A1 Guo N. Huang YR 2017 UL http://biorxiv.org/content/early/2017/04/05/124347.abstract AB Adult mammalian hearts typically have little capacity to regenerate after injuries such as myocardial infarction. In contrast, neonatal mice during the first week of life possess an incredible ability to regenerate their hearts, though this capacity is lost shortly after birth. The physiological triggers mediating this transition remains poorly understood. In this study, we demonstrate that sympathetic nerve activity promotes cardiomyocyte cell-cycle arrest and binucleation. In mice hearts lacking sympathetic nerve inputs, we observe increased mononucleated cardiomyocyte numbers and elevated cardiomyocyte proliferation. Additionally, increased cardiomyocyte mononucleation and proliferation are observed in mice with genetic and pharmacological inhibition of β-adrenergic receptors (βARs), which mediate sympathetic nerve signaling. Using in vitro cultures of neonatal cardiomyocytes, we demonstrate that activation of β-adrenergic receptors results in decreased cardiomyocyte proliferation that is mediated through cyclic AMP-dependent protein kinase (PKA) signaling. Taken together, these results suggest that sympathetic nerve activity may play a role in limiting the ability of mammalian hearts to regenerate by restricting cardiomyocyte proliferation and promoting cytokinesis failure leading to multinucleation.