TY - JOUR
T1 - Integrins Increase Sarcoplasmic Reticulum Activity for Excitation-Contraction Coupling in Human Stem Cell-Derived Cardiomyocytes
AU - Wang, Brian X
AU - Kane, Christopher
AU - Nicastro, Laura
AU - King, Oisín
AU - Kit-Anan, Worrapong
AU - Downing, Barrett
AU - Deidda, Graziano
AU - Couch, Liam S
AU - Pinali, Christian
AU - Mitraki, Anna
AU - MacLeod, Kenneth T
AU - Terracciano, Cesare M
N1 - Funding Information:
This work was supported by the British Heart Foundation [MB/PhD Studentships—FS/13/46/30282 to C.K. and FS/16/76/32409 to B.X.W.]. G. D. and A. M. acknowledge support from “AngioMatTrain” Marie-Curie Initial Training Network (ITN), call FP7-PEOPLE-2012 ITN, grant agreement number 317304.
Publisher Copyright:
© 2022 by the authors.
PY - 2022/9/19
Y1 - 2022/9/19
N2 - Engagement of the sarcoplasmic reticulum (SR) Ca2+ stores for excitation-contraction (EC)-coupling is a fundamental feature of cardiac muscle cells. Extracellular matrix (ECM) proteins that form the extracellular scaffolding supporting cardiac contractile activity are thought to play an integral role in the modulation of EC-coupling. At baseline, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) show poor utilisation of SR Ca2+ stores, leading to inefficient EC-coupling, like developing or human CMs in cardiac diseases such as heart failure. We hypothesised that integrin ligand-receptor interactions between ECM proteins and CMs recruit the SR to Ca2+ cycling during EC-coupling. hiPSC-CM monolayers were cultured on fibronectin-coated glass before 24 h treatment with fibril-forming peptides containing the integrin-binding tripeptide sequence arginine-glycine-aspartic acid (2 mM). Micropipette application of 40 mM caffeine in standard or Na+/Ca2+-free Tyrode's solutions was used to assess the Ca2+ removal mechanisms. Microelectrode recordings were conducted to analyse action potentials in current-clamp. Confocal images of labelled hiPSC-CMs were analysed to investigate hiPSC-CM morphology and ultrastructural arrangements in Ca2+ release units. This study demonstrates that peptides containing the integrin-binding sequence arginine-glycine-aspartic acid (1) abbreviate hiPSC-CM Ca2+ transient and action potential duration, (2) increase co-localisation between L-type Ca2+ channels and ryanodine receptors involved in EC-coupling, and (3) increase the rate of SR-mediated Ca2+ cycling. We conclude that integrin-binding peptides induce recruitment of the SR for Ca2+ cycling in EC-coupling through functional and structural improvements and demonstrate the importance of the ECM in modulating cardiomyocyte function in physiology.
AB - Engagement of the sarcoplasmic reticulum (SR) Ca2+ stores for excitation-contraction (EC)-coupling is a fundamental feature of cardiac muscle cells. Extracellular matrix (ECM) proteins that form the extracellular scaffolding supporting cardiac contractile activity are thought to play an integral role in the modulation of EC-coupling. At baseline, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) show poor utilisation of SR Ca2+ stores, leading to inefficient EC-coupling, like developing or human CMs in cardiac diseases such as heart failure. We hypothesised that integrin ligand-receptor interactions between ECM proteins and CMs recruit the SR to Ca2+ cycling during EC-coupling. hiPSC-CM monolayers were cultured on fibronectin-coated glass before 24 h treatment with fibril-forming peptides containing the integrin-binding tripeptide sequence arginine-glycine-aspartic acid (2 mM). Micropipette application of 40 mM caffeine in standard or Na+/Ca2+-free Tyrode's solutions was used to assess the Ca2+ removal mechanisms. Microelectrode recordings were conducted to analyse action potentials in current-clamp. Confocal images of labelled hiPSC-CMs were analysed to investigate hiPSC-CM morphology and ultrastructural arrangements in Ca2+ release units. This study demonstrates that peptides containing the integrin-binding sequence arginine-glycine-aspartic acid (1) abbreviate hiPSC-CM Ca2+ transient and action potential duration, (2) increase co-localisation between L-type Ca2+ channels and ryanodine receptors involved in EC-coupling, and (3) increase the rate of SR-mediated Ca2+ cycling. We conclude that integrin-binding peptides induce recruitment of the SR for Ca2+ cycling in EC-coupling through functional and structural improvements and demonstrate the importance of the ECM in modulating cardiomyocyte function in physiology.
KW - Arginine/metabolism
KW - Aspartic Acid/metabolism
KW - Caffeine/pharmacology
KW - Calcium/metabolism
KW - Fibronectins/metabolism
KW - Glycine/metabolism
KW - Humans
KW - Induced Pluripotent Stem Cells
KW - Integrins/metabolism
KW - Ligands
KW - Myocytes, Cardiac/metabolism
KW - Ryanodine Receptor Calcium Release Channel/metabolism
KW - Sarcoplasmic Reticulum/metabolism
U2 - 10.3390/ijms231810940
DO - 10.3390/ijms231810940
M3 - Article
C2 - 36142853
VL - 23
JO - International Journal of Molecular Sciences
JF - International Journal of Molecular Sciences
SN - 1661-6596
IS - 18
M1 - 10940
ER -