Human induced pluripotent stem cell-based platform for modeling cardiac ischemia

Abstract

Ischemic heart disease is a major cause of death worldwide, and the only available therapy to salvage the tissue is reperfusion, which can initially cause further damage. Many therapeutics that have been promising in animal models have failed in human trials. Thus, functional human based cardiac ischemia models are required. In this study, a human induced pluripotent stem cell derived-cardiomyocyte (hiPSC-CM)-based platform for modeling ischemia–reperfusion was developed utilizing a system enabling precise control over oxygen concentration and real-time monitoring of the oxygen dynamics as well as iPS-CM functionality. In addition, morphology and expression of hypoxia-related genes and proteins were evaluated as hiPSC-CM response to 8 or 24 h hypoxia and 24 h reoxygenation. During hypoxia, initial decrease in hiPSC-CM beating frequency was observed, after which the CMs adapted to the conditions and the beating frequency gradually increased already before reoxygenation. During reoxygenation, the beating frequency typically first surpassed the baseline before settling down to the values close the baseline. Furthermore, slowing on the field potential propagation throughout the hiPSC-CM sheet as well as increase in depolarization time and decrease in overall field potential duration were observed during hypoxia. These changes were reversed during reoxygenation. Disorganization of sarcomere structures was observed after hypoxia and reoxygenation, supported by decrease in the expression of sarcomeric proteins. Furthermore, increase in the expression of gene encoding glucose transporter 1 was observed. These findings indicate, that despite their immature phenotype, hiPSC-CMs can be utilized in modeling ischemia–reperfusion injury.

Metabolic Maturation Increases Susceptibility to Hypoxia-induced Damage in Human iPSC-derived Cardiomyocytes

“… 42 Hypoxia and reoxygenation have previously been shown to induce only limited damage and prolonged hypoxia without reoxygenation did not affect beating frequency in immature iPSC-CMs. 36 This is in line with our results of maintained beating frequency in immature, non-MM iPSC-CMs after prolonged hypoxia. A previously observed limited effect of hypoxia compared to reperfusion injury on calcium overload-related cellular damage in immature iPSC-CMs, 43 potentially explains why our seahorse results do show a response of iPSC-CMs in RPMI-media to hypoxia.…”

“…The observed ability of conventionally cultured, non-MM iPSC-CMs to increase the glycolytic flux in anaerobic conditions is in line with the characteristics of fetal immature CMs having a higher threshold for oxygen insufficiency. 36-38 During development, arterial blood oxygen saturation fluctuates around 3% O 2 , which would be considered a hypoxic condition in the adult human heart, with respect to activation of hypoxia-induced gene expression. 37 However, fetal immature CMs are conditioned to low oxygen pressures during development and thus rely on anaerobic energy pathways for metabolism and cardiac growth.…”

Multi-Omics Characterization of a Human Stem Cell-Based Model of Cardiac Hypertrophy

“…hiPSC-derived CMs have been used for the development of several in vitro disease models [31][32][33]. They have shown to be promising for studies of cardiac hypertrophy, with characteristics resembling the in vivo situation.…”

Generating 3D human cardiac constructs from pluripotent stem cells

“…For example, genetic cardiac disease models have been constructed using iPSCs derived from patients suffering from hereditary long QT syndrome, hypertrophic cardiomyopathy, and dilated cardiomyopathy. [18][19][20][21] Non genetic diseases, such as ischemia injury, [22][23][24] hormone induced hypertrophy, 14,15,25 drug induced cytotoxicity [26][27][28] and metabolic dysfunction [29][30][31] have also been successfully modeled using hPSC-CMs in vitro. 2D PSC-CM model has several advantages: (1) Compared with 3D model, 2D cell culture system is relatively simpler and easier to conduct molecular biological experiments such as gene editing.…”