β2-Adrenergic agonists and the treatment of skeletal muscle wasting disorders

beta 2-Agonists are traditionally used for the treatment of bronchospasm associated with asthma and the treatment of symptomatic patients with COPD. However, beta 2-agonists are also powerful anabolic agents that trigger skeletal muscle hypertrophy. Investigating the effects of beta 2-agonists in skeletal muscle over the past 30 years in different animal models has led to the identification of potential therapeutic applications in several muscle wasting disorders, including neuromuscular diseases, cancer cachexia, sepsis or thermal injury. In these conditions, numerous studies indicate that beta 2-agonists can attenuate and/or reverse the decrease in skeletal muscle mass and associated weakness in animal models of muscle wasting but also in human patients. The purpose of this review is to present the biological and clinical significance of beta 2-agonists for the treatment of skeletal muscle wasting. After the description of the molecular mechanisms involved in the hypertrophy and anti-atrophy effect of beta 2-agonists, we will review the anti-atrophy effects of beta 2-agonist administration in several animal models and human pathologies associated with or leading to skeletal muscle wasting. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting. (C) 2013 Elsevier Ltd. All rights reserved.