Phospholamban as a crucial determinant of the inotropic response of human pluripotent stem cell-derived ventricular cardiomyocytes and engineered 3-dimensional tissue constructs.
Circ Arrhythm Electrophysiol
; 8(1): 193-202, 2015 Feb.
Article
em En
| MEDLINE
| ID: mdl-25504561
ABSTRACT
BACKGROUND:
Human (h) embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) serve as a potential unlimited ex vivo source of cardiomyocytes (CMs). However, a well-accepted roadblock has been their immature phenotype. hESC/iPSC-derived ventricular (v) CMs and their engineered cardiac microtissues (hvCMTs) similarly displayed positive chronotropic but null inotropic responses to ß-adrenergic stimulation. Given that phospholamban (PLB) is robustly present in adult but poorly expressed in hESC/iPSC-vCMs and its defined biological role in ß-adrenergic signaling, we investigated the functional consequences of PLB expression in hESC/iPSC-vCMs and hvCMTs. METHODS ANDRESULTS:
First, we confirmed that PLB protein was differentially expressed in hESC (HES2, H9)- and iPSC-derived and adult vCMs. We then transduced hES2-vCMs with the recombinant adenoviruses (Ad) Ad-PLB or Ad-S16E-PLB to overexpress wild-type PLB or the pseudophosphorylated point-mutated variant, respectively. As anticipated from the inhibitory effect of unphosphorylated PLB on sarco/endoplasmic reticulum Ca2+-ATPase, Ad-PLB transduction significantly attenuated electrically evoked Ca2+ transient amplitude and prolonged the 50% decay time. Importantly, Ad-PLB-transduced hES2-vCMs uniquely responded to isoproterenol. Ad-S16E-PLB-transduced hES2-vCMs displayed an intermediate phenotype. The same trends were observed with H9- and iPSC-vCMs. Directionally, similar results were also seen with Ad-PLB-transduced and Ad-S16E-transduced hvCMTs. However, Ad-PLB altered neither the global transcriptome nor ICa,L, implicating a PLB-specific effect.CONCLUSIONS:
Engineered upregulation of PLB expression in hESC/iPSC-vCMs restores a positive inotropic response to ß-adrenergic stimulation. These results not only provide a better mechanistic understanding of the immaturity of hESC/iPSC-vCMs but will also lead to improved disease models and transplantable prototypes with adult-like physiological responses.Palavras-chave
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Base de dados:
MEDLINE
Assunto principal:
Proteínas de Ligação ao Cálcio
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Diferenciação Celular
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Engenharia Tecidual
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Miócitos Cardíacos
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Células-Tronco Embrionárias
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Células-Tronco Pluripotentes Induzidas
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Contração Miocárdica
Limite:
Humans
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article