The p38-PGC-1α-irisin-betatrophin axis: Exploring new pathways in insulin resistance.

The discovery of irisin as a novel and promising peptidic hormone has raised hopes regarding the hypothesis that irisin may provide additional benefits, not only for obesity and diabetes, but also for a wide range of pathological conditions since this hormone may prove to be therapeutically and clinically beneficial. In addition, a new hormone, betatrophin, has recently been identified by Yi and coworkers. Both hormones are connected by a new pathway clearly involved in insulin resistance. We hypothesize here how these hormones may be linked and their possible implications in both aged-reduced restricted regenerative capacity and dedifferentiated β cells of diabetic patients.