In Vitro Studies of Human Cardiac Tissue

The definitive treatment of severe heart failure is heart transplantation; however the number of heart transplantation procedures performed in Japan per year ranges from 30-40 due to donor shortage. Therefore, recently other treatments such as ventricular assist device or regenerative therapy by human cardiac tissue engineering have been developed and are considered as appropriate alternatives. We have developed an original technology, which was named cell-sheet based tissue engineering to fabricate functional three-dimensional tissue by layering cell sheets. The utilization of this technique allowed us to successfully engineer thick rat cardiac tissue with perfusable blood vessels in vitro. Here, we demonstrate a technique to engineer human cardiac tissue with perfusable blood vessels using cardiac cell sheets derived from human induced pluripotent stem cells, and porcine small intestine as a vascular bed for perfusion culture. The small intestine was harvested from with a branch of the superior mesenteric artery and vein and underwent mucosal resection after harvested tissue was cut open. To engineer cardiac tissue with perfusable blood vessels, cardiac cell sheets co-cultured with endothelial cells, were triple-layered and then was overlaid on the vascular bed in the bioreactor system. One day after perfusion culture, overlaid cardiac tissues pulsated spontaneously and were synchronized. The cardiac tissue construct was viable tissue without any observable necrosis. Furthermore we examined the possibility of transplantation of the in vitro engineered human cardiac tissue with the connectable host artery and vein. Engineered cardiac tissue was removed from the bioreactor system after 4-day perfusion, and transplanted to another pig heart. The branch of the superior mesenteric artery and vein of the graft were then reconnected to the host internal thoracic artery and vein. When the cardiac tissue reperfused, it began to beat spontaneously after a few minutes. We believe that this method is useful to fabricate functional cardiac tissue and may become an appropriate treatment for severe heart failure.

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A three-dimensional hybrid pacemaker electrode seamlessly integrates into engineered, functional human cardiac tissue in vitro

Scientific Reports ◽

10.1038/s41598-018-32790-8 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 9

Author(s):

Tobias Weigel ◽

Tobias Schmitz ◽

Tobias Pfister ◽

Sabine Gaetzner ◽

Maren Jannasch ◽

...

Keyword(s):

Cardiac Tissue ◽

Three Dimensional ◽

Human Cardiac Tissue

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SARS-CoV-2 infects and induces cytotoxic effects in human cardiomyocytes

10.1101/2020.06.01.127605 ◽

2020 ◽

Cited By ~ 4

Author(s):

Denisa Bojkova ◽

Julian Wagner ◽

Mariana Shumliakivska ◽

Galip Aslan ◽

Umber Saleem ◽

...

Keyword(s):

Cardiac Tissue ◽

Cardiac Injury ◽

Transcriptional Response ◽

Human Cardiomyocytes ◽

Global Pandemic ◽

Virus Rna ◽

Human Cardiac Tissue ◽

Induced Pluripotent ◽

Apoptotic Effects

Background: The coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has emerged as global pandemic. SARS-CoV-2 infection can lead to elevated markers of cardiac injury associated with higher risk of mortality in COVID-19 patients. It is unclear whether cardiac injury may have been caused by direct infection of cardiomyocytes or is mainly secondary to lung injury and inflammation. Here we investigate whether human cardiomyocytes are permissive for SARS-CoV-2 infection. Methods: Infection was induced by two strains of SARS-CoV-2 (FFM1 and FFM2) in human induced pluripotent stem cells-derived cardiomyocytes (hiPS-CM) and in two models of human cardiac tissue. Results: We show that SARS-CoV-2 infects hiPS-CM as demonstrated by detection of intracellular double strand viral RNA and viral spike glycoprotein protein expression. Increasing concentrations of virus RNA are detected in supernatants of infected cardiomyocytes, which induced infections in CaCo-2 cell lines documenting productive infections. SARS-COV-2 infection induced cytotoxic and pro-apoptotic effects and abolished cardiomyocyte beating. RNA sequencing confirmed a transcriptional response to viral infection as demonstrated by the up-regulation of genes associated with pathways related to viral response and interferon signaling, apoptosis and reactive oxygen stress. SARS-CoV-2 infection and cardiotoxicity was confirmed in a iPS-derived human 3D cardiosphere tissue models. Importantly, viral spike protein and viral particles were detected in living human heart slices after infection with SARS-CoV-2. Conclusions: The demonstration that cardiomyocytes are permissive for SARS-CoV-2 infection in vitro warrants the further in depth monitoring of cardiotoxic effects in COVID-19 patients.

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In situ analysis of mitochondrial respiratory capacity - foundation for cellular physiology

Medicinski pregled ◽

10.2298/mpns1712445g ◽

2017 ◽

Vol 70 (11-12) ◽

pp. 445-448

Author(s):

Enis Garipi ◽

Aleksandra Rakovac ◽

Otto Barak ◽

Damir Lukac ◽

Nada Naumovic ◽

...

Keyword(s):

Mitochondrial Function ◽

Cardiac Tissue ◽

Mitochondrial Enzymes ◽

Respiratory Chain Complexes ◽

Respiratory Capacity ◽

Complex Structural ◽

Human Cardiac Tissue ◽

Novi Sad

Mitochondria are ubiquitous organelles of eukaryotic cells and they are the mayor site of generating energy in the form of adenosine triphoshate through the process of oxidative phosphorylation. Analysis and estimation of mitochondrial function is of outmost importance when it comes to studying intracellular energy metabolism, mechanisms of apoptosis, signaling pathways, calcium storage and the pathophysiology of a large spectrum of human diseases including various neurodegenerative diseases, myopathies, metabolic syndromes and cancer. Respiratory capacity analysis covers one of the many roles that mitochondria play in living cells and it provides us with useful data about functional integrity of mitochondria. Assessment of individual respiratory chain complexes or other mitochondrial enzymes has been widely used to estimate mitochondrial function and dysfunction but it neglects the influence of complex structural and functional interplay of mitochondrial proteins and enzymes and plasmic compounds. Another method that emphasises the importance of studying intact mitochondria is in vitro technique, and although it has many advantages, in some aspects it is far from being representative when it comes to functional assessment of mitochondria. From the perspective of energy production and consumption, the cardiac muscle is a highly demanding tissue and it is the well functioning of mitochondria that is conditio sine qua non for this nature to be fulfilled. In cooperation with the University of Split School of Medicine in Split and under the mentorship of Prof. Marko Ljubkovic, the Department of Physiology of the Faculty of Medicine Novi Sad works on introducing in situ approaches in the analysis of respiratory mitochondrial function in skinned muscle fibers of human cardiac tissue.

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Comparable Decellularization of Fetal and Adult Cardiac Tissue Explants as 3D-like Platforms for In Vitro Studies

Journal of Visualized Experiments ◽

10.3791/56924 ◽

2019 ◽

Cited By ~ 1

Author(s):

Ana C. Silva ◽

Maria J. Oliveira ◽

Todd C McDevitt ◽

Mário A. Barbosa ◽

Diana S. Nascimento ◽

...

Keyword(s):

Cardiac Tissue ◽

In Vitro Studies ◽

Tissue Explants

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A Possible Mechanism behind Faster Clearance and Higher Peak Concentrations of Cardiac Troponin I Compared with Troponin T in Acute Myocardial Infarction

Clinical Chemistry ◽

10.1093/clinchem/hvz003 ◽

2020 ◽

Vol 66 (2) ◽

pp. 333-341 ◽

Cited By ~ 3

Author(s):

Karin Starnberg ◽

Vincent Fridén ◽

Aida Muslimovic ◽

Sven-Erik Ricksten ◽

Susanne Nyström ◽

...

Keyword(s):

Myocardial Infarction ◽

Heart Failure ◽

Acute Myocardial Infarction ◽

Cardiac Troponin ◽

Cardiac Tissue ◽

Troponin I ◽

Troponin T ◽

Cardiac Troponin I ◽

Human Cardiac Tissue

Abstract Background Although cardiac troponin I (cTnI) and troponin T (cTnT) form a complex in the human myocardium and bind to thin filaments in the sarcomere, cTnI often reaches higher concentrations and returns to normal concentrations faster than cTnT in patients with acute myocardial infarction (MI). Methods We compared the overall clearance of cTnT and cTnI in rats and in patients with heart failure and examined the release of cTnT and cTnI from damaged human cardiac tissue in vitro. Results Ground rat heart tissue was injected into the quadriceps muscle in rats to simulate myocardial damage with a defined onset. cTnT and cTnI peaked at the same time after injection. cTnI returned to baseline concentrations after 54 h, compared with 168 h for cTnT. There was no difference in the rate of clearance of solubilized cTnT or cTnI after intravenous or intramuscular injection. Renal clearance of cTnT and cTnI was similar in 7 heart failure patients. cTnI was degraded and released faster and reached higher concentrations than cTnT when human cardiac tissue was incubated in 37°C plasma. Conclusion Once cTnI and cTnT are released to the circulation, there seems to be no difference in clearance. However, cTnI is degraded and released faster than cTnT from necrotic cardiac tissue. Faster degradation and release may be the main reason why cTnI reaches higher peak concentrations and returns to normal concentrations faster in patients with MI.

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Processing of Human Cardiac Tissue Toward Extracellular Matrix Self-assembling Hydrogel for In Vitro and In Vivo Applications

Journal of Visualized Experiments ◽

10.3791/56419 ◽

2017 ◽

Cited By ~ 4

Author(s):

Matthias Becker ◽

Janita A. Maring ◽

Barbara Oberwallner ◽

Benjamin Kappler ◽

Oliver Klein ◽

...

Keyword(s):

Extracellular Matrix ◽

Cardiac Tissue ◽

Self Assembling ◽

Human Cardiac Tissue

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Revision of the Troponin T Release Mechanism from Damaged Human Myocardium

Clinical Chemistry ◽

10.1373/clinchem.2013.217943 ◽

2014 ◽

Vol 60 (8) ◽

pp. 1098-1104 ◽

Cited By ~ 32

Author(s):

Karin Starnberg ◽

Anders Jeppsson ◽

Bertil Lindahl ◽

Ola Hammarsten

Keyword(s):

Myocardial Infarction ◽

Cardiac Tissue ◽

Troponin T ◽

Heart Tissue ◽

Release Mechanism ◽

Cardiac Damage ◽

Salt Extraction ◽

Low Salt ◽

Human Cardiac Tissue

Abstract BACKGROUND Cardiac troponin T (cTnT) is released from damaged heart tissue in patients with acute myocardial infarction. It is presumed that most cTnT is tightly bound and released following the degradation of myofibrils in necrotic cardiomyocytes, resulting in sustained increases in circulating cTnT. Evidence of a large irreversibly bound fraction is based on the inability to extract most cTnT from cardiac tissue in cold low-salt extraction buffers. METHODS Here we examined in vitro extraction of cTnT from human cardiac tissue in serum at 37 °C. RESULTS We found that over 80% of the cTnT can be extracted from human cardiac tissue in 90 min using large volumes of human serum at 37 °C. The release ratio was highly dependent on the extraction volume and was only 3% if an equal volume of serum and heart tissue was used. In contrast, extraction of the cytoplasmic cardiac damage markers myoglobin and creatinine kinase was much less affected by changing these conditions. Purified cTnT was poorly soluble in a low-salt extraction buffer at 0 °C, previously used to define the free cTnT fraction. CONCLUSIONS Our data indicate that the diffusible fraction of cTnT is likely substantially larger in vivo than previously reported and likely is not fixed but dependent on local plasma flow. It is therefore possible that the sustained increase in circulating cTnT after myocardial infarction is at least in part due to a slow washout of cTnT that interacts reversibly with tropomyosin in myofibrils.

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