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In vitro Assessment of Myocardial Protection following Hypothermia-Preconditioning in a Human Cardiac Myocytes Model
Published on: October 27, 2020
Occult cardiotoxicity--toxic effects on cardiac ischemic tolerance
Eliahu Golomb1, Abraham Nyska, Herzl Schwalb
1Department of Pathology, Shaare Zedek Medical Center, Jerusalem 91031, Israel. egolomb@bgu.ac.il
Toxicologic Pathology
|June 19, 2009
Summary
Certain drugs and toxins can harm the heart during ischemic events by reducing cardiac ischemic tolerance, an effect termed "occult cardiotoxicity." Current toxicological studies miss this, highlighting the need for new assessment methods.
Area of Science:
- Cardiology
- Toxicology
- Biochemistry
Background:
- Cardiac ischemic tolerance is crucial for outcomes of heart attacks.
- This tolerance involves intrinsic myocardial reserves and signaling pathways, primarily affecting mitochondria.
- Current toxicological assessments do not evaluate effects on ischemic tolerance.
Purpose of the Study:
- To review mechanisms of cardiac ischemic tolerance.
- To discuss methods for assessing cardiac ischemic tolerance.
- To highlight the impact of drugs and toxins on cardiac ischemic tolerance, introducing the concept of 'occult cardiotoxicity'.
Main Methods:
- Literature review of studies on cardiac ischemic tolerance.
- Analysis of signaling pathways and cellular mechanisms involved in myocardial protection.
- Evaluation of current toxicological testing limitations.
Main Results:
- Cardiac ischemic tolerance is modulated by signal transduction pathways converging on mitochondria.
- Drugs and toxins can impair ischemic tolerance without affecting function under normal oxygen conditions.
- This impairment, termed 'occult cardiotoxicity,' is not detected by standard toxicological studies.
Conclusions:
- Low cardiac ischemic tolerance may represent a premorbid state, increasing cardiac morbidity.
- 'Occult cardiotoxicity' is a significant, underrecognized risk associated with certain compounds.
- Toxicological assessments should incorporate the evaluation of effects on cardiac ischemic tolerance.
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