DLK1 and type 2 diabetes mellitus: In this study, the stimulatory effect of Dlk1/FA1 on increasing the production of IL-6 and monocyte chemotactic protein (MCP)-1 by myotubes did not seem to be involved in pathogenesis of insulin resistance in T2D patients (Kalupahana et al., 2012) due to the fact that we could not detect any differences in the FA1-induced pro-inflammatory cytokines in myotubes between T2D and lean and obese controls.