Abstract:
Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) are a cell model now widely used to investigate pathophysiological features of cardiac tissue. Given the invaluable contribution hiPSC-CM could make for studies on cardio-metabolic disorders by defining a postnatal metabolic phenotype, our work herein focused on monitoring the insulin response in CM derived from the hiPSC line UKBi015-B. Western blot analysis on total cell lysates obtained from hiPSC-CM showed increased phosphorylation of both AKT and AS160 following insulin treatment, but failed to highlight any changes in the expression dynamics of the glucose transporter GLUT4. By contrast, the Western blot analysis of membrane fractions, rather than total lysates, revealed insulin-induced plasma membrane translocation of GLUT4, which is known to also occur in postnatal CM. Thus, these findings suggest that hiPSC-derived CMs exhibit an insulin response reminiscent to that of adult CMs regarding intracellular signaling and GLUT4 translocation to the plasma membrane, representing a suitable cellular model in the cardio-metabolic research field. Moreover, our studies also demonstrate the relevance of analyzing membrane fractions rather than total lysates in order to monitor GLUT4 dynamics in response to metabolic regulators in hiPSC-CMs.
摘要:
人诱导多能干细胞来源的心肌细胞(hiPSC-CM)是目前广泛用于研究心脏组织病理生理学特征的细胞模型。鉴于hiPSC-CM通过定义出生后代谢表型可以为心脏代谢紊乱的研究做出宝贵的贡献,我们的工作集中在监测源自hiPSC系UKBi015-B的CM中的胰岛素反应。从hiPSC-CM获得的总细胞裂解物的蛋白质印迹分析显示,胰岛素治疗后AKT和AS160的磷酸化增加。但未能强调葡萄糖转运蛋白GLUT4表达动力学的任何变化。相比之下,膜组分的蛋白质印迹分析,而不是总裂解物,揭示了胰岛素诱导的GLUT4质膜易位,已知这也发生在产后CM中。因此,这些发现表明,hiPSC衍生的CM表现出胰岛素反应,让人联想到成人CM关于细胞内信号传导和GLUT4易位到质膜,代表了心脏代谢研究领域中合适的细胞模型。此外,我们的研究还证明了分析膜组分而不是总裂解物的相关性,以监测hiPSC-CM中响应代谢调节剂的GLUT4动力学。