Mechanism of automaticity in cardiomyocytes derived from human induced pluripotent stem cells.
Mechanism of automaticity in cardiomyocytes derived from human induced pluripotent stem cells.
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DOI：
10.1016/j.yjmcc.2015.01.013
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发表时间：
2015-04
影响因子：
5
通讯作者：
Salama, Guy
中科院分区：
文献类型：
--
作者：
Kim, Jong J.;Yang, Lei;Lin, Bo;Zhu, Xiaodong;Sun, Bin;Kaplan, Aaron D.;Bett, Glenna C. L.;Rasmusson, Randall L.;London, Barry;Salama, Guy
关键词：
由人类诱导多能干细胞(HIPS-CMS)产生的心肌细胞的产生引起了广泛的兴奋，基于个性化药物诊断和治疗心血管疾病的前景。HIPS-CMS的一个共同特征是自发收缩，但其机制(S)仍不清楚。在亚细胞分辨和药物干预下，用电压钳技术、动作电位(AP)和细胞内钙瞬变(CAI)的光学标测来研究内源性活动。尽管存在高水平的HCN转录本(1-4)，但起搏器电流的抑制剂伊夫拉定并不改变HIPS-CMS单层自发CAIT(SCaiT)的频率。HIPS-CMS的If和Ik1(内向整流钾电流)可忽略不计，最小舒张期电位−为59.1±3.3 mV(n=18)。在APS上升之前，一只去极化的脚与蔡的崛起重合。亚细胞CAI波的幅度变化、传播和消亡；较大的CAI波触发细胞扫描和AP。当去钙离子(0.0 5~-1.8 mM)、异丙肾上腺素(1μM)或咖啡因(10 0μM)时，SCaiT频率增加(n≥5，p<；0.0 5)。Ryanodine受体稳定剂(K201=2μM)、丁卡因、钠钙交换(Ncx)抑制剂(SEA0400=2μM)、高[K+]OUT(5→8 mM)和硫醇还原剂使HIPS-CMS静息，但仍可被电刺激以诱发CaiT。细胞间隙连接蛋白-43的表达和Cait的增殖表明HIPS-CM在单层中存在细胞间的偶联。来自分散的HIPS-CMS集合的SCaiT是异相的，但通过相互连接的微管的延伸而变得同步。HIPS-CMS的自律性源于一种钙时钟机制，该机制涉及钙离子在与NCX相连的肌浆网中循环，以触发AP。
The creation of cardiomyocytes derived from human induced pluripotent stem cells (hiPS-CMs) has spawned broad excitement borne out of the prospects to diagnose and treat cardiovascular diseases based on personalized medicine. A common feature of hiPS-CMs is their spontaneous contractions but the mechanism(s) remain uncertain. Intrinsic activity was investigated by the voltage-clamp technique, optical mapping of action potentials (APs) and intracelular Ca2+ (Cai) transients (CaiT) at subcellular-resolution and pharmacological interventions. The frequency of spontaneous CaiT (sCaiT) in monolayers of hiPS-CMs was not altered by ivabradine, an inhibitor of the pacemaker current, If despite high levels of HCN transcripts (1–4). HiPS-CMs had negligible If and IK1 (inwardly-rectifying K+-current) and a minimum diastolic potential of −59.1±3.3mV (n=18). APs upstrokes were preceded by a depolarizing-foot coincident with a rise of Cai. Subcellular Cai wavelets varied in amplitude, propagated and died-off ; larger Cai-waves triggered cellular sCaTs and APs. SCaiTs increased in frequency with [Ca2+]out (0.05-to-1.8mM), isoprotererol (1μM) or caffeine (100μM) (n≥5, p<0.05). HiPS-CMs became quiescent with ryanodine receptor stabilizers (K201=2μM); tetracaine; Na-Ca exchange (NCX) inhibition (SEA0400=2μM); higher [K+]out (5→8mM), and thiol-reducing agents but could still be electrically stimulated to elicit CaiTs. Cell-cell coupling of hiPS-CM in monolayers was evident from connexin-43 expression and CaiT propagation. SCaiTs from an ensemble of dispersed hiPS-CMs were out-of-phase in but became synchronous through the outgrowth of inter-connecting microtubules. Automaticity in hiPS-CMs originates from a Ca2+-clock mechanism involving Ca2+ cycling across the sarcoplasmic reticulum linked to NCX to trigger APs.
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影响因子：
5.5
作者：
Bett, Glenna C. L.;Kaplan, Aaron D.;Lis, Agnieszka;Cimato, Thomas R.;Tzanakakis, Emmanuel S.;Zhou, Qinlian;Morales, Michael J.;Rasmusson, Randall L.
通讯作者：
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影响因子：
64.8
作者：
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作者：
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Mugelli, A
影响因子：
9.3
作者：
Cerbai, Elisabetta;Mugelli, Alessandro
通讯作者：
Mugelli, Alessandro
影响因子：
3.8
作者：
Bucchi, Annalisa;Baruscotti, Mirko;DiFrancesco, Dario
通讯作者：
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