TY - JOUR
T1 - A cardiomyocyte show of force
T2 - A fluorescent alpha-actinin reporter line sheds light on human cardiomyocyte contractility versus substrate stiffness
AU - Ribeiro, Marcelo C.
AU - Slaats, Rolf H.
AU - Schwach, Verena
AU - Rivera Arbelaez, José M.
AU - Tertoolen, Leon G.J.
AU - van Meer, Berend J.
AU - Molenaar, Robert
AU - Mummery, Christine L.
AU - Claessens, Mireille M.A.E.
AU - Passier, Robert
N1 - Elsevier deal
PY - 2020/4/1
Y1 - 2020/4/1
N2 - Cardiovascular disease is often associated with cardiac remodeling, including cardiac fibrosis, which may lead to increased stiffness of the heart wall. This stiffness in turn may cause subsequent failure of cardiac myocytes, however the response of these cells to increased substrate stiffness is largely unknown. To investigate the contractile response of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) to increased substrate stiffness, we generated a stable transgenic human pluripotent stem cell line expressing a fusion protein of α-Actinin and fluorescent mRubyII in a previously characterized NKX2.5-GFP reporter line. Cardiomyocytes differentiated from this line were subjected to a substrate with stiffness ranging from 4 kPa to 101 kPa, while contraction of sarcomeres and bead displacement in the substrate were measured for each single cardiomyocyte. We found that sarcomere dynamics in hPSC-CMs on polyacrylamide gels of increasing stiffness are not affected above physiological levels (21 kPa), but that contractile force increases up to a stiffness of 90 kPa, at which cell shortening, deducted from bead displacement, is significantly reduced compared to physiological stiffness. We therefore hypothesize that this discrepancy may be the cause of intracellular stress that leads to hypertrophy and consequent heart failure in vivo.
AB - Cardiovascular disease is often associated with cardiac remodeling, including cardiac fibrosis, which may lead to increased stiffness of the heart wall. This stiffness in turn may cause subsequent failure of cardiac myocytes, however the response of these cells to increased substrate stiffness is largely unknown. To investigate the contractile response of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) to increased substrate stiffness, we generated a stable transgenic human pluripotent stem cell line expressing a fusion protein of α-Actinin and fluorescent mRubyII in a previously characterized NKX2.5-GFP reporter line. Cardiomyocytes differentiated from this line were subjected to a substrate with stiffness ranging from 4 kPa to 101 kPa, while contraction of sarcomeres and bead displacement in the substrate were measured for each single cardiomyocyte. We found that sarcomere dynamics in hPSC-CMs on polyacrylamide gels of increasing stiffness are not affected above physiological levels (21 kPa), but that contractile force increases up to a stiffness of 90 kPa, at which cell shortening, deducted from bead displacement, is significantly reduced compared to physiological stiffness. We therefore hypothesize that this discrepancy may be the cause of intracellular stress that leads to hypertrophy and consequent heart failure in vivo.
KW - UT-Hybrid-D
KW - Alpha-actinin
KW - Transgenic model
KW - Contractility
KW - Substrate stiffness
UR - http://www.scopus.com/inward/record.url?scp=85082432551&partnerID=8YFLogxK
U2 - 10.1016/j.yjmcc.2020.03.008
DO - 10.1016/j.yjmcc.2020.03.008
M3 - Article
SN - 0022-2828
VL - 141
SP - 54
EP - 64
JO - Journal of molecular and cellular cardiology
JF - Journal of molecular and cellular cardiology
ER -