Ca2+ signaling in human induced pluripotent stem cell-derived cardiomyocytes (iPS-CM) from normal and catecholaminergic polymorphic ventricular tachycardia (CPVT)-afflicted subjects
Ca2+ signaling in human induced pluripotent stem cell-derived cardiomyocytes (iPS-CM) from normal and catecholaminergic polymorphic ventricular tachycardia (CPVT)-afflicted subjects
复制标题
DOI：
10.1016/j.ceca.2013.04.004
复制
发表时间：
2013-08-01
期刊：
影响因子：
4
通讯作者：
Morad, M.
中科院分区：
文献类型：
--
作者：
Zhang, X. -H.;Haviland, S.;Morad, M.
从诱导多能干细胞（iPS-CM）衍生心肌细胞使我们能够探测来自健康和儿茶酚胺能多态性室性心动过速（CPVT 1）患者的人iPS-CM的Ca 2+信号传导参数，所述患者在兰尼碱受体（RyR 2）中携带新的点突变p.F2483I。iPS-CM在分化的第30-40天解离，并在3-6天内进行膜片钳。在对照和突变体iPS-CM中，钙电流（I-Ca）平均类似于8 pA/pF。I-Ca诱导的对照组和突变体细胞的Ca ~（2+）瞬变具有与I-Ca相似的钟形电压依赖性，符合Ca ~（2+）诱导的Ca ~（2+）释放（CICR）机制。在两种细胞类型中，I-Ca激活的与咖啡因触发的Ca 2+瞬变的比率相似于0.3。咖啡因诱导的Ca 2+瞬变产生显着较小的Na+-Ca 2+交换器电流（I-NCX）在突变体细胞，反映其较小的Ca 2 +-商店。与成年心肌细胞一样，CICR的增加是电压依赖性的。肾上腺素能激动剂增强I-Ca，但差异改变CICR增益，舒张期Ca 2+，和Ca 2 +-火花突变细胞。突变体细胞，当Ca 2+超载时，显示出更长的和游走的Ca 2+火花，激活相邻的释放位点，在-30 mV具有更大的CICR增益，但较小的Ca 2+储存。我们得出结论，控制和突变iPS-CM表达成人心肌细胞Ca 2+信号表型。RyR 2 F2483 I突变型心肌细胞具有异常的单一Ca 2+信号传导、较小的Ca 2+储存、较高的CICR增益和致敏的肾上腺素能调节，这与CPVT综合征功能改变的Ca 2+释放特征一致。(C)2013爱思唯尔有限公司保留所有权利。
Derivation of cardiomyocytes from induced pluripotent stem cells (iPS-CMs) allowed us to probe the Ca2+-signaling parameters of human iPS-CMs from healthy- and catecholaminergic polymorphic ventricular tachycardia (CPVT1)-afflicted individuals carrying a novel point mutation p.F2483I in ryanodine receptors (RyR2). iPS-CMs were dissociated on day 30-40 of differentiation and patch-clamped within 3-6 days. Calcium currents (I-Ca) averaged similar to 8 pA/pF in control and mutant iPS-CMs. I-Ca-induced Ca2+-transients in control and mutant cells had bell-shaped voltage-dependence similar to that of I-Ca, consistent with Ca2+-induced Ca2+-release (CICR) mechanism. The ratio of I-Ca -actiyated to caffeine-triggered Ca2+-transients was similar to 0.3 in both cell types. Caffeine-induced Ca2+-transients generated significantly smaller Na+-Ca2+ exchanger current (I-NCX) in mutant cells, reflecting their smaller Ca2+-stores. The gain of CICR was voltage-dependent as in adult cardiomyocytes. Adrenergic agonists enhanced I-Ca, but differentially altered the CICR gain, diastolic Ca2+, and Ca2+-sparks in mutant cells. The mutant cells, when Ca2+-overloaded, showed longer and wandering Ca2+-sparks that activated adjoining release sites, had larger CICR gain at -30 mV yet smaller Ca2+-stores. We conclude that control and mutant iPS-CMs express the adult cardiomyocyte Ca2+-signaling phenotype. RyR2 F2483I mutant myocytes have aberrant unitary Ca2+-signaling, smaller Ca2+-stores, higher CICR gains, and sensitized adrenergic regulation, consistent with functionally altered Ca2+-release profile of CPVT syndrome. (C) 2013 Elsevier Ltd. All rights reserved.