Spontaneously Beating Cardiac Spheroids: 3D Combined Hypertrophy & Cardiotoxicity Assay
Detect therapeutically relevant pathophysiological hypertrophic cardiotoxicity potential of novel therapeutics using Cyprotex’s 3D combined cardiac hypertrophy and multi-parametric high content screening (HCS) cardiotoxicity assay.
Cyprotex delivers consistent, high quality data with the flexibility to adapt protocols based on specific customer requirements.
Introduction
- Drug-induced cardiovascular toxicity is the leading cause of attrition during drug development. Drugs can exert functional toxicities such as arrhythmia or morphological (structural) damage including changes to the myocardium1. Evaluation of the potential for both types of cardiotoxicity by novel compounds is essential for the discovery of safe drugs.
- The myocardial tissue comprises only 30% cardiomyocytes, despite this they comprise the majority of the cardiac tissue mass. These terminally differentiated cardiomyocytes can only respond with hypertrophic growth (increased muscle mass) to external stimuli2.
- Various stimuli are known to induce cardiac hypertrophy including mechanical and oxidative stress as well as neurohormonal perturbation and metabolic hypoxia2. Hypertrophy can be physiologically induced or a pathophysiological response to toxicity.
- Mitochondrial disruption, calcium dyshomeostasis and cellular ATP content have been previously identified as major targets for structural cardiotoxins3 and are used to indicate pathophysiological hypertrophy.
- Three dimensional (3D) high content screening (HCS) allows temporal monitoring of cardiomyocyte spheroid hypertrophy over a 14 day repeat dose period with a terminal measure of mitochondrial function, calcium homeostasis, DNA structure and cellular ATP at day 14.
Protocol
Protocol for 3D Structural Cardiotoxicity and Hypertrophy Assay
Data
Data from Cyprotex's 3D Structural Cardiotoxicity & Hypertrophy Assay
Utilizing the 3D cardiac combined assay approach all reference compound toxicities were correctly predicted within a 10x Cmax cut off. Structural cardiotoxicity was correctly predicted for 94% and pathophysiological hypertrophy potential (PHP) for 81% of the compound set within a 10x Cmax cut off.
The combination of an in vitro 3D model that better recapitulates the in vivo cellular physiology of cardiac tissue with multiparametric temporal HCS and a cytotoxicity assay presents a viable screening strategy for the accurate in vivo relevant detection of novel therapeutics that cause structural cardiotoxicity with pathophysiological hypertrophy potential early in drug development.
References
1) Laverty H et al., (2011). How can we improve our understanding of cardiovascular safety liabilities to develop safer medicines? Br J Pharmacol 163(4), 675-693
2) Brutsaert DL (2003). Cardiac endothelial-myocardial signaling: its role in cardiac growth, contractile performance, and rhythmicity. Phys Rev 83(1), 59-11
3) Pointon A et al., (2013) Phenotypic profiling of structural cardiotoxins in vitro reveals dependency on multiple mechanisms of toxicity. Toxicol Sci 132(2), 317-326
4) Cross MJ et al., (2015) Physiological, pharmacological and toxicological considerations of drug-induced structural cardiac injury. Br J Pharmacol 172(4), 957-974
5) Nam KH et al., (2015) Biomimetic 3D tissue models for advanced high-throughput drug screening. J Lab Autom 20(3); 201-215