Editorial
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Feb 26, 2019; 11(2): 47-56
Published online Feb 26, 2019. doi: 10.4330/wjc.v11.i2.47
Not all arrestins are created equal: Therapeutic implications of the functional diversity of the β-arrestins in the heart
Anastasios Lymperopoulos, Shelby L Wertz, Celina M Pollard, Victoria L Desimine, Jennifer Maning, Katie A McCrink
Anastasios Lymperopoulos, Shelby L Wertz, Celina M Pollard, Victoria L Desimine, Jennifer Maning, Katie A McCrink, Laboratory for the Study of Neurohormonal Control of the Circulation, Department of Pharmaceutical Sciences (Pharmacology), College of Pharmacy, Nova Southeastern University, Fort Lauderdale, FL 33328, United States
Jennifer Maning, Jackson Memorial Hospital, Miami, FL 33136, United States
Katie A McCrink, Massachusetts General Hospital, Boston, MA 02114, United States
Author contributions: All authors performed literature research and contributed to the writing of the manuscript; Lymperopoulos A supervised the project and wrote the paper.
Supported by a NSU’s President’s Faculty Research and Development Grant (PFRDG).
Conflict-of-interest statement: The authors declare no conflict of interest related to this publication.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Anastasios Lymperopoulos, BPharm, MSc, PhD, FAHA, FESC, Associate Professor, Laboratory for the Study of Neurohormonal Control of the Circulation, Department of Pharmaceutical Sciences (Pharmacology), College of Pharmacy, Nova Southeastern University, 3200 S. University Dr., HPD (Terry) Bldg/Room 1338, Fort Lauderdale, FL33328, United States. al806@nova.edu
Telephone: +1-954-262-1338 Fax: +1-954-262-2278
Received: October 16, 2018
Peer-review started: October 16, 2018
First decision: November 15, 2018
Revised: November 28, 2018
Accepted: January 10, 2019
Article in press: January 10, 2019
Published online: February 26, 2019
Processing time: 132 Days and 7.8 Hours
Abstract

The two ubiquitous, outside the retina, G protein-coupled receptor (GPCR) adapter proteins, β-arrestin-1 and -2 (also known as arrestin-2 and -3, respectively), have three major functions in cells: GPCR desensitization, i.e., receptor decoupling from G-proteins; GPCR internalization via clathrin-coated pits; and signal transduction independently of or in parallel to G-proteins. Both β-arrestins are expressed in the heart and regulate a large number of cardiac GPCRs. The latter constitute the single most commonly targeted receptor class by Food and Drug Administration-approved cardiovascular drugs, with about one-third of all currently used in the clinic medications affecting GPCR function. Since β-arrestin-1 and -2 play important roles in signaling and function of several GPCRs, in particular of adrenergic receptors and angiotensin II type 1 receptors, in cardiac myocytes, they have been a major focus of cardiac biology research in recent years. Perhaps the most significant realization coming out of their studies is that these two GPCR adapter proteins, initially thought of as functionally interchangeable, actually exert diametrically opposite effects in the mammalian myocardium. Specifically, the most abundant of the two β-arrestin-1 exerts overall detrimental effects on the heart, such as negative inotropy and promotion of adverse remodeling post-myocardial infarction (MI). In contrast, β-arrestin-2 is overall beneficial for the myocardium, as it has anti-apoptotic and anti-inflammatory effects that result in attenuation of post-MI adverse remodeling, while promoting cardiac contractile function. Thus, design of novel cardiac GPCR ligands that preferentially activate β-arrestin-2 over β-arrestin-1 has the potential of generating novel cardiovascular therapeutics for heart failure and other heart diseases.

Keywords: Adverse remodeling; β-arrestin; Biased signaling; Cardiac myocyte; Cardiac fibroblast; contractility; Functional divergence; G protein-coupled receptor; Heart failure; Hormone; Myocardial infarction; Signal transducer

Core tip: Presumed functionally similar for a long time, we now know that the two β-arrestins display significant functional diversity in several organs and tissues, including in the cardiovascular system. Their functional distinction also in the mammalian heart has been clearly documented over the past few years. β-arrestin-1, which is far more abundant than β-arrestin-2 in almost every tissue including the myocardium, opposes the cyclic adenosine monophosphate (cAMP)-dependent pro-contractile signaling of the β1 adrenergic receptor (β1AR), and promotes cardiac apoptosis, inflammation, and other adverse remodeling-associated processes post-myocardial infarction. Conversely, β-arrestin-2 promotes catecholamine-dependent cardiac contractility directly, via SERCA2a potentiation, and indirectly, by leaving β1AR’s cAMP-dependent pro-contractile signaling unaffected.