Role of β-adrenergic receptors in insulin resistance: Induction or protection?

Abstract

β-Adrenergic receptors (βARs), in particular β2-subtype, are key regulators of glucose homeostasis. Previous studies  showed that activation of hepatic and adipose tissue βARs mediates insulin desensitizing effects. On the contrary,  activation of βARs in the skeletal muscle enhances glucose uptake. However, there is a lot of controversy regarding the  metabolic effects of systemic administration of either βAR agonists or antagonists. β2-Agonists have been shown to  substantially impair glucose homeostasis while improving it with long-term systemic administration. In the same  context, acute and chronic systemic use of certain types of βblockers have been found to enhance insulin action. In this  review article, we try to elaborate the underlying mechanisms that regulate glucose metabolism after acute and chronic  systemic use of βAR agonists and antagonists in an attempt to answer the question "Do βARs induce or protect against  insulin resistance?"