New and Emerging Therapies and Targets: Beta-3 Agonists

Area of Science:

• Cardiovascular Physiology
• Pharmacology
• Molecular Biology

Background:

• The adrenergic system is vital for stress response but can maladaptive in heart failure.
• Current beta-blocker therapies target beta-1 and beta-2 adrenergic receptors (B1-2AR).
• Beta-3 adrenergic receptors (B3AR) are newly identified in cardiac cells, suggesting potential protective roles.

Purpose of the Study:

• To review B3AR signaling in the cardiovascular system.
• To summarize evidence for B3AR's beneficial effects in cardiovascular conditions.
• To outline a clinical trial testing a B3AR agonist in heart failure patients.

Main Methods:

• Review of existing literature on B3AR signaling and cardiovascular effects.
• Description of preclinical findings supporting B3AR activation.
• Outline of an ongoing clinical trial design for heart failure with preserved ejection fraction (HFpEF).

Main Results:

• B3AR activation is linked to nitric oxide and antioxidant pathways.
• Preclinical studies suggest B3AR expression/activation benefits myocardial remodeling.
• An ongoing clinical trial is evaluating mirabegron, a B3AR agonist, in HFpEF patients.

Conclusions:

• B3AR represents a novel therapeutic target for heart failure.
• Specific B3AR agonists like mirabegron warrant clinical investigation.
• Targeting B3AR may offer a new strategy for managing heart failure, particularly HFpEF.