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Enhancing the Engraftment of Human Induced Pluripotent Stem Cell-derived Cardiomyocytes via a Transient Inhibition of Rho Kinase Activity
Published on: July 10, 2019
SiRNA-mediated knockdown of TOP2B protects hiPSC-derived cardiomyocytes from doxorubicin-induced toxicity
Neha Saroj1, Pankaj Singh Dholaniya1, Syed Baseeruddin Alvi2
1Division of Basic and Translational Research, Department of Emergency Medicine, The Ohio State University, Columbus, OH, USA; Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA; Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, India.
Aims:
Doxorubicin (Dox) is a potent chemotherapeutic agent, but its use is limited by cardiotoxicity, primarily due to the disruption of Topoisomerase-2 beta (TOP2B) activity. Dexrazoxane (Dex), an FDA-approved cardioprotective drug, alleviates Dox-induced toxicity but lacks heart-specific targeting. This study investigates siRNA-mediated TOP2B knockdown as a more targeted strategy to protect cardiomyocytes from Dox-induced damage.
Materials And Methods:
Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were treated with siRNA to knock down TOP2B and were then exposed to Dox. We compared the cardioprotective effects of siRNA-mediated knockdown to Dex treatment using cell viability, cell toxicity assay and electrophysiological evaluation was performed using a multielectrode array (MEA).
Key Findings:
Our results demonstrate that TOP2B silencing significantly decreases apoptosis and improved cell viability, as compared to the Dex treatment. Additionally, electrophysiological assays using a Multielectrode Array (MEA) demonstrated enhanced contractility and conductivity in siRNA-treated hiPSC-CMs. Furthermore, transmission electron microscopy (TEM) data revealed that TOP2B knockdown preserves mitochondrial morphology and sarcomere structure, compared to Dox and Dex-treated groups.
Significance:
These findings suggest that siRNA-mediated TOP2B inhibition could provide a safer, more specific approach to mitigate Dox-induced cardiotoxicity.
Insights
Targeted silencing of Topoisomerase-2 beta (TOP2B) using siRNA protects heart cells from chemotherapy drug Doxorubicin (Dox) damage. This approach shows improved cell viability and function compared to current treatments, offering a safer strategy against Dox-induced cardiotoxicity.
Area of Science:
- Cardiology
- Molecular Biology
- Pharmacology
Background:
- Doxorubicin (Dox) is a vital chemotherapy drug, but its clinical use is restricted by dose-limiting cardiotoxicity.
- Doxorubicin-induced cardiotoxicity is primarily mediated by the disruption of Topoisomerase-2 beta (TOP2B) activity in cardiomyocytes.
- Dexrazoxane (Dex) is an FDA-approved cardioprotective agent but lacks tissue-specific targeting, limiting its efficacy and potentially causing side effects.
Purpose of the Study:
- To investigate the potential of siRNA-mediated TOP2B knockdown as a targeted strategy to prevent Doxorubicin-induced cardiotoxicity.
- To compare the cardioprotective efficacy of TOP2B silencing with the established cardioprotective drug Dexrazoxane (Dex).
Main Methods:
- Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were utilized for in vitro studies.
- TOP2B was silenced in hiPSC-CMs using small interfering RNA (siRNA).
- Treated and untreated hiPSC-CMs were subsequently exposed to Doxorubicin (Dox).
- Cardioprotective effects were assessed via cell viability assays, cell toxicity assays, and electrophysiological evaluations using a multielectrode array (MEA).
- Ultrastructural changes were examined using transmission electron microscopy (TEM).
Main Results:
- TOP2B silencing significantly reduced apoptosis and enhanced cell viability in hiPSC-CMs compared to Dex treatment.
- Electrophysiological assessments via MEA indicated improved cardiac contractility and conductivity in siRNA-treated cells.
- TEM analysis revealed that TOP2B knockdown preserved mitochondrial morphology and sarcomere structure, unlike Dox or Dex treatments.
Conclusions:
- siRNA-mediated TOP2B inhibition presents a promising, targeted approach to mitigate Doxorubicin-induced cardiotoxicity.
- This strategy offers a potentially safer and more specific alternative to current cardioprotective methods, preserving cardiomyocyte function and integrity.
