Facilitated maturation of Ca2+ handling properties of human embryonic stem cell-derived cardiomyocytes by calsequestrin expression
Facilitated maturation of Ca2+ handling properties of human embryonic stem cell-derived cardiomyocytes by calsequestrin expression
复制标题
DOI：
10.1152/ajpcell.00060.2009
复制
发表时间：
2009-07-01
影响因子：
5.5
通讯作者：
Li, Ronald A.
中科院分区：
文献类型：
--
作者：
Liu, Jing;Lieu, Deborah K.;Li, Ronald A.
刘杰，刘德康，萧周文，傅金东，谢洪福，李瑞安。通过钙螯合蛋白表达促进人胚胎干细胞来源的心肌细胞 Ca2+ 处理特性的成熟。 Am J Physiol Cell Physiol 297: C152-C159, 2009。首次发表于 2009 年 4 月 8 日； doi:10.1152/ajpcell.00060.2009.-心肌细胞 (CM) 是不可再生的。自我更新的多能人类胚胎干细胞 (hESC) 可以分化为用于细胞疗法的 CM。我们最近报道了 Ca2+ 处理对于 hESC 衍生的 CM (hESC-CM) 的兴奋-收缩耦合至关重要，它具有功能但不成熟。胞质 Ca2+ 瞬时幅度较小、动力学较慢以及肌浆网 (SR) Ca2+ 含量降低等不成熟特性可归因于 hESC-CM 及其成体对应物中特定 Ca2+ 处理和调节蛋白的发育表达谱差异。特别是，钙螯合蛋白 (CSQ) 是 SR 中最丰富、高容量但亲和力低的 Ca2+ 结合蛋白，锚定在兰尼碱受体上，在成人 CM 中强烈表达，但在 hESC-CM 中完全不表达。在这里，我们假设 hESC-CM 中 CSQ 的基因转移足以诱导 SR 功能的改善。与对照 Ad-CMV-GFP (Ad-GFP) 和 Ad-CMV-CSQ Delta-IRES-GFP (Ad-CSQ Delta，其介导非功能性、 CSQ 的截断版本）组。 Ad-CSQ 增加了 SR Ca2+ 含量，但没有改变 L 型 Ca2+ 电流。在药理学上，未转导的野生型、Ad-GFP、Ad-CSQ Delta 和 Ad-CSQ 转导的 hESC-CM 表现相似。兰尼碱显着降低了 Ca2+ 瞬态幅度并减慢了上冲程，而毒胡萝卜素则减慢了衰减。三联蛋白和连接蛋白均不受影响。我们得出结论，hESC-CM 中的 CSQ 表达促进 Ca2+ 处理成熟。我们的结果让我们深入了解 hESC-CM 是否适合治疗以及作为某些心脏病模型进行药物筛选。
Liu J, Lieu DK, Siu CW, Fu JD, Tse HF, Li RA. Facilitated maturation of Ca2+ handling properties of human embryonic stem cell-derived cardiomyocytes by calsequestrin expression. Am J Physiol Cell Physiol 297: C152-C159, 2009. First published April 8, 2009; doi:10.1152/ajpcell.00060.2009.-Cardiomyocytes (CMs) are nonregenerative. Self-renewable pluripotent human embryonic stem cells (hESCs) can differentiate into CMs for cell-based therapies. We recently reported that Ca2+ handling, crucial to excitation-contraction coupling of hESC-derived CMs (hESC-CMs), is functional but immature. Such immature properties as smaller cytosolic Ca2+ transient amplitudes, slower kinetics, and reduced Ca2+ content of sarcoplasmic reticulum (SR)can be attributed to the differential developmental expression profiles of specific Ca2+ handling and regulatory proteins in hESC-CMs and their adult counterparts. In particular, calsequestrin (CSQ), the most abundant, high-capacity but low-affinity, Ca2+ binding protein in the SR that is anchored to the ryanodine receptor, is robustly expressed in adult CMs but completely absent in hESC-CMs. Here we hypothesized that gene transfer of CSQ in hESC-CMs suffices to induce functional improvement of SR. Transduction of hESC-CMs by the recombinant adenovirus Ad-CMV-CSQ-IRES-GFP (Ad-CSQ) significantly increased the transient amplitude, upstroke velocity, and transient decay compared with the control Ad-CMV-GFP (Ad-GFP) and Ad-CMV-CSQ Delta-IRES-GFP (Ad-CSQ Delta, which mediated the expression of a nonfunctional, truncated version of CSQ) groups. Ad-CSQ increased the SR Ca2+ content but did not alter L-type Ca2+ current. Pharmacologically, untransduced wildtype, Ad-GFP-, Ad-CSQ Delta-, and Ad-CSQ-transduced hESC-CMs behaved similarly. Whereas ryanodine significantly reduced the Ca2+ transient amplitude and slowed the upstroke, thapsigargin slowed the decay. Neither triadin nor junctin was affected. We conclude that CSQ expression in hESC-CMs facilitates Ca2+ handling maturation. Our results shed insights into the suitability of hESC-CMs for therapies and as certain heart disease models for drug screening.