Is irisin an early marker of statin-induced myopathy? Bench to the bedside

Evaluation of: Gouni-Berthold I, Berthold HK, Huh JY et al. Effects of lipid-lowering drugs on irisin in human subjects in vivo and in human skeletal muscle cells ex vivo. PLoS ONE 8(9), e72858 (2013). Irisin is a myokine that has recently gained interest for its role in glucose metabolism. It is known that age and muscle mass are the primary predictors of irisin concentration. However, the underlying mechanisms detailing the pathways affected by irisin are not clear. In this work, levels of irisin were measured in young, healthy individuals. The first part of the study was focused on understanding the regulation of irisin levels based on multiple baseline parameters, such as lipoprotein(a) and cholesterol levels. The second part of the study assessed the effect of lipid-lowering agents - simvastatin and ezetimibe - on serum irisin levels. Furthermore, the authors expanded the study by conducting in vitro experiments on human skeletal muscle cells to understand the biochemical mechanisms regulating the effect of simvastatin on irisin expression.