Chronic intermittent tachypacing by an optogenetic approach induces arrhythmia vulnerability in human engineered heart tissue

Abstract Aims Chronic tachypacing is commonly used in animals to induce cardiac dysfunction and to study mechanisms of heart failure and arrhythmogenesis. Human induced pluripotent stem cells (hiPSC) may replace animal models to overcome species differences and ethical problems. Here, 3D engineered heart tissue (EHT) was used to investigate the effect of chronic tachypacing on hiPSC-cardiomyocytes (hiPSC-CMs). Methods and results To avoid cell toxicity by electrical pacing, we developed an optogenetic approach. EHTs were transduced with lentivirus expressing channelrhodopsin-2 (H134R) and stimulated by 15 s bursts of blue light pulses (0.3 mW/mm2, 30 ms, 3 Hz) separated by 15 s without pacing for 3 weeks. Chronic optical tachypacing did not affect contractile peak force, but induced faster contraction kinetics, shorter action potentials, and shorter effective refractory periods. This electrical remodelling increased vulnerability to tachycardia episodes upon electrical burst pacing. Lower calsequestrin 2 protein levels, faster diastolic depolarization (DD) and efficacy of JTV-519 (46% at 1 µmol/L) to terminate tachycardia indicate alterations of Ca2+ handling being part of the underlying mechanism. However, other antiarrhythmic compounds like flecainide (69% at 1 µmol/L) and E-4031 (100% at 1 µmol/L) were also effective, but not ivabradine (1 µmol/L) or SEA0400 (10 µmol/L). Conclusion We demonstrated a high vulnerability to tachycardia of optically tachypaced hiPSC-CMs in EHT and the effective termination by ryanodine receptor stabilization, sodium or hERG potassium channel inhibition. This new model might serve as a preclinical tool to test antiarrhythmic drugs increasing the insight in treating ventricular tachycardia.

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Human Induced Pluripotent Stem Cell–Derived Engineered Heart Tissue as a Sensitive Test System for QT Prolongation and Arrhythmic Triggers

Circulation Arrhythmia and Electrophysiology ◽

10.1161/circep.117.006035 ◽

2018 ◽

Vol 11 (7) ◽

Cited By ~ 25

Author(s):

Marc D. Lemoine ◽

Tobias Krause ◽

Jussi T. Koivumäki ◽

Maksymilian Prondzynski ◽

Mirja L. Schulze ◽

...

Keyword(s):

Stem Cell ◽

Pluripotent Stem Cell ◽

Induced Pluripotent Stem Cell ◽

Heart Tissue ◽

Test System ◽

Qt Prolongation ◽

Sensitive Test ◽

Engineered Heart Tissue ◽

Induced Pluripotent

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Cardiac repair in guinea pigs with human engineered heart tissue from induced pluripotent stem cells

Science Translational Medicine ◽

10.1126/scitranslmed.aaf8781 ◽

2016 ◽

Vol 8 (363) ◽

pp. 363ra148-363ra148 ◽

Cited By ~ 106

Author(s):

F. Weinberger ◽

K. Breckwoldt ◽

S. Pecha ◽

A. Kelly ◽

B. Geertz ◽

...

Keyword(s):

Stem Cells ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Guinea Pigs ◽

Heart Tissue ◽

Cardiac Repair ◽

Engineered Heart Tissue ◽

Induced Pluripotent

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An Important Role for DNMT3A-Mediated DNA Methylation in Cardiomyocyte Metabolism and Contractility

Circulation ◽

10.1161/circulationaha.119.044444 ◽

2020 ◽

Vol 142 (16) ◽

pp. 1562-1578

Author(s):

Alexandra Madsen ◽

Grit Höppner ◽

Julia Krause ◽

Marc N. Hirt ◽

Sandra D. Laufer ◽

...

Keyword(s):

Gene Expression ◽

Dna Methylation ◽

Stem Cells ◽

Stem Cell ◽

Pluripotent Stem Cells ◽

Pluripotent Stem Cell ◽

Induced Pluripotent Stem Cell ◽

Heart Tissue ◽

Engineered Heart Tissue ◽

Induced Pluripotent

Background: DNA methylation acts as a mechanism of gene transcription regulation. It has recently gained attention as a possible therapeutic target in cardiac hypertrophy and heart failure. However, its exact role in cardiomyocytes remains controversial. Thus, we knocked out the main de novo DNA methyltransferase in cardiomyocytes, DNMT3A, in human induced pluripotent stem cells. Functional consequences of DNA methylation-deficiency under control and stress conditions were then assessed in human engineered heart tissue from knockout human induced pluripotent stem cell–derived cardiomyocytes. Methods: DNMT3A was knocked out in human induced pluripotent stem cells by CRISPR/Cas9gene editing. Fibrin-based engineered heart tissue was generated from knockout and control human induced pluripotent stem cell–derived cardiomyocytes. Development and baseline contractility were analyzed by video-optical recording. Engineered heart tissue was subjected to different stress protocols, including serum starvation, serum variation, and restrictive feeding. Molecular, histological, and ultrastructural analyses were performed afterward. Results: Knockout of DNMT3A in human cardiomyocytes had three main consequences for cardiomyocyte morphology and function: (1) Gene expression changes of contractile proteins such as higher atrial gene expression and lower MYH7/MYH6 ratio correlated with different contraction kinetics in knockout versus wild-type; (2) Aberrant activation of the glucose/lipid metabolism regulator peroxisome proliferator-activated receptor gamma was associated with accumulation of lipid vacuoles within knockout cardiomyocytes; (3) Hypoxia-inducible factor 1α protein instability was associated with impaired glucose metabolism and lower glycolytic enzyme expression, rendering knockout-engineered heart tissue sensitive to metabolic stress such as serum withdrawal and restrictive feeding. Conclusion: The results suggest an important role of DNA methylation in the normal homeostasis of cardiomyocytes and during cardiac stress, which could make it an interesting target for cardiac therapy.

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Transcriptome analysis of non human primate-induced pluripotent stem cell-derived cardiomyocytes in 2D monolayer culture vs. 3D engineered heart tissue

Cardiovascular Research ◽

10.1093/cvr/cvaa281 ◽

2020 ◽

Author(s):

Huaxiao Yang ◽

Ningyi Shao ◽

Alexandra Holmström ◽

Xin Zhao ◽

Tony Chour ◽

...

Keyword(s):

Stem Cell ◽

Monolayer Culture ◽

Induced Pluripotent Stem Cell ◽

Heart Tissue ◽

Paracrine Signalling ◽

Engineered Heart Tissue ◽

Direct Cell ◽

Induced Pluripotent ◽

Transcriptome Level

Abstract Aims Stem cell therapy has shown promise for treating myocardial infarction via re-muscularization and paracrine signalling in both small and large animals. Non-human primates (NHPs), such as rhesus macaques (Macaca mulatta), are primarily utilized in preclinical trials due to their similarity to humans, both genetically and physiologically. Currently, induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) are delivered into the infarcted myocardium by either direct cell injection or an engineered tissue patch. Although both approaches have advantages in terms of sample preparation, cell–host interaction, and engraftment, how the iPSC-CMs respond to ischaemic conditions in the infarcted heart under these two different delivery approaches remains unclear. Here, we aim to gain a better understanding of the effects of hypoxia on iPSC-CMs at the transcriptome level. Methods and results NHP iPSC-CMs in both monolayer culture (2D) and engineered heart tissue (EHT) (3D) format were exposed to hypoxic conditions to serve as surrogates of direct cell injection and tissue implantation in vivo, respectively. Outcomes were compared at the transcriptome level. We found the 3D EHT model was more sensitive to ischaemic conditions and similar to the native in vivo myocardium in terms of cell–extracellular matrix/cell–cell interactions, energy metabolism, and paracrine signalling. Conclusion By exposing NHP iPSC-CMs to different culture conditions, transcriptome profiling improves our understanding of the mechanism of ischaemic injury.

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What is the immunologic impact after transplantation of a novel fibrin-based type of engineered heart tissue?

The Thoracic and Cardiovascular Surgeon ◽

10.1055/s-0032-1332453 ◽

2013 ◽

Vol 61 (S 01) ◽

Author(s):

L Conradi ◽

S Schmidt ◽

L Peters ◽

A Eder ◽

A Hansen ◽

...

Keyword(s):

Heart Tissue ◽

Engineered Heart Tissue

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Pharmacology of Ivabradine and the Effect on Chronic Heart Failure

Current Topics in Medicinal Chemistry ◽

10.2174/1568026619666190809093144 ◽

2019 ◽

Vol 19 (21) ◽

pp. 1878-1901 ◽

Cited By ~ 3

Author(s):

Yue Zhou ◽

Jian Wang ◽

Zhuo Meng ◽

Shuang Zhou ◽

Jiayu Peng ◽

...

Keyword(s):

Heart Failure ◽

Heart Rate ◽

Chronic Heart Failure ◽

Underlying Mechanism ◽

Clinical Syndrome ◽

Hcn Channels ◽

Therapeutic Effects ◽

Diastolic Depolarization ◽

High Incidence ◽

Spontaneous Phase

Chronic Heart Failure (CHF) is a complex clinical syndrome with a high incidence worldwide. Although various types of pharmacological and device therapies are available for CHF, the prognosis is not ideal, for which, the control of increased Heart Rate (HR) is critical. Recently, a bradycardic agent, ivabradine, is found to reduce HR by inhibiting the funny current (If). The underlying mechanism states that ivabradine can enter the Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels and bind to the intracellular side, subsequently inhibiting the If. This phenomenon can prolong the slow spontaneous phase in the diastolic depolarization, and thus, reduce HR. The clinical trials demonstrated the significant effects of the drug on reducing HR and improving the symptoms of CHF with fewer adverse effects. This review primarily introduces the chemical features and pharmacological characteristics of ivabradine and the mechanism of treating CHF. Also, some expected therapeutic effects on different diseases were also concluded. However, ivabradine, as a typical If channel inhibitor, necessitates additional research to verify its pharmacological functions.

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Glyoxalase I disruption and external carbonyl stress impair mitochondrial function in human induced pluripotent stem cells and derived neurons

Translational Psychiatry ◽

10.1038/s41398-021-01392-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tomonori Hara ◽

Manabu Toyoshima ◽

Yasuko Hisano ◽

Shabeesh Balan ◽

Yoshimi Iwayama ◽

...

Keyword(s):

Oxidative Stress ◽

Stem Cells ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Caspase 3 ◽

Intervention Strategy ◽

Underlying Mechanism ◽

Carbonyl Stress ◽

Gene Encoding ◽

Induced Pluripotent

AbstractCarbonyl stress, a specific form of oxidative stress, is reported to be involved in the pathophysiology of schizophrenia; however, little is known regarding the underlying mechanism. Here, we found that disruption of GLO1, the gene encoding a major catabolic enzyme scavenging the carbonyl group, increases vulnerability to external carbonyl stress, leading to abnormal phenotypes in human induced pluripotent stem cells (hiPSCs). The viability of GLO1 knockout (KO)-hiPSCs decreased and activity of caspase-3 was increased upon addition of methylglyoxal (MGO), a reactive carbonyl compound. In the GLO1 KO-hiPSC-derived neurons, MGO administration impaired neurite extension and cell migration. Further, accumulation of methylglyoxal-derived hydroimidazolone (MG-H1; a derivative of MGO)-modified proteins was detected in isolated mitochondria. Mitochondrial dysfunction, including diminished membrane potential and dampened respiratory function, was observed in the GLO1 KO-hiPSCs and derived neurons after addition of MGO and hence might be the mechanism underlying the effects of carbonyl stress. The susceptibility to MGO was partially rescued by the administration of pyridoxamine, a carbonyl scavenger. Our observations can be used for designing an intervention strategy for diseases, particularly those induced by enhanced carbonyl stress or oxidative stress.

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Hereditary Optic Neuropathies: Induced Pluripotent Stem Cell-Based 2D/3D Approaches

Genes ◽

10.3390/genes12010112 ◽

2021 ◽

Vol 12 (1) ◽

pp. 112

Author(s):

Marta García-López ◽

Joaquín Arenas ◽

M. Esther Gallardo

Keyword(s):

Stem Cell ◽

Retinal Ganglion Cells ◽

Pluripotent Stem Cell ◽

Ganglion Cells ◽

Genetic Disorders ◽

Three Dimensional ◽

Induced Pluripotent Stem Cell ◽

Underlying Mechanism ◽

Retinal Ganglion ◽

Induced Pluripotent

Inherited optic neuropathies share visual impairment due to the degeneration of retinal ganglion cells (RGCs) as the hallmark of the disease. This group of genetic disorders are caused by mutations in nuclear genes or in the mitochondrial DNA (mtDNA). An impaired mitochondrial function is the underlying mechanism of these diseases. Currently, optic neuropathies lack an effective treatment, and the implementation of induced pluripotent stem cell (iPSC) technology would entail a huge step forward. The generation of iPSC-derived RGCs would allow faithfully modeling these disorders, and these RGCs would represent an appealing platform for drug screening as well, paving the way for a proper therapy. Here, we review the ongoing two-dimensional (2D) and three-dimensional (3D) approaches based on iPSCs and their applications, taking into account the more innovative technologies, which include tissue engineering or microfluidics.

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Cardiomyocytes Derived from Induced Pluripotent Stem Cells as a Disease Model for Propionic Acidemia

International Journal of Molecular Sciences ◽

10.3390/ijms22031161 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1161

Author(s):

Esmeralda Alonso-Barroso ◽

Belén Pérez ◽

Lourdes Ruiz Desviat ◽

Eva Richard

Keyword(s):

Stem Cells ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Ex Vivo ◽

Disease Model ◽

Propionic Acidemia ◽

Heart Tissue ◽

Altered Expression ◽

Cellular Models ◽

Induced Pluripotent

Propionic acidemia (PA), one of the most frequent life-threatening organic acidemias, is caused by mutations in either the PCCA or PCCB genes encoding both subunits of the mitochondrial propionyl-CoA carboxylase (PCC) enzyme. Cardiac alterations (hypertrophy, dilated cardiomyopathy, long QT) are one of the major causes of mortality in patients surviving the neonatal period. To overcome limitations of current cellular models of PA, we generated induced pluripotent stem cells (iPSCs) from a PA patient with defects in the PCCA gene, and successfully differentiated them into cardiomyocytes. PCCA iPSC-derived cardiomyocytes exhibited reduced oxygen consumption, an accumulation of residual bodies and lipid droplets, and increased ribosomal biogenesis. Furthermore, we found increased protein levels of HERP, GRP78, GRP75, SIG-1R and MFN2, suggesting endoplasmic reticulum stress and calcium perturbations in these cells. We also analyzed a series of heart-enriched miRNAs previously found deregulated in the heart tissue of a PA murine model and confirmed their altered expression. Our novel results show that PA iPSC-cardiomyocytes represent a promising model for investigating the pathological mechanisms underlying PA cardiomyopathies, also serving as an ex vivo platform for therapeutic evaluation.

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