Stress and cardiac beta adrenoceptors

Area of Science:

• Cardiology
• Stress Physiology
• Molecular Biology

Background:

• Stress is a significant trigger for numerous diseases, often linked to allostatic overload.
• Catecholamines and glucocorticoids are key regulators of physiological homeostasis during stress.
• Adrenergic receptors (beta-ARs) mediate cardiac responses to catecholamines, influencing heart rate, contractility, and cardiomyocyte survival.

Purpose of the Study:

• To review the structural basis, signaling pathways, and adaptive responses of beta-AR subtypes during stress.
• To discuss the role of beta3- and beta4-ARs, including low-affinity isoforms, in cardiac function under stress.
• To examine alterations in beta-AR signaling in pathogenic conditions and during stress.

Main Methods:

• Review of current literature on stress, catecholamines, and cardiac adrenergic receptor signaling.
• Analysis of the structural and functional characteristics of various beta-AR subtypes.
• Examination of adaptive responses and changes in beta-AR signaling under stress and disease.

Main Results:

• Beta1- and beta2-ARs are primarily involved in mediating catecholamine effects on the heart, controlling chronotropic, inotropic, and lusitropic responses.
• Beta-ARs regulate cardiomyocyte growth and death, contributing to cardiac remodeling.
• Low-affinity beta-AR isoforms and potential beta3/beta4-ARs may play roles in cardiac function during stress.

Conclusions:

• Adrenergic receptor signaling is a critical determinant of cardiac adaptation and maladaptation to stress.
• Understanding beta-AR subtype function and signaling plasticity is essential for addressing stress-induced cardiovascular pathology.
• Further research into less-characterized beta-ARs and their roles in cardiac stress response is warranted.