Hexarelin Signaling to PPARγ in Metabolic Diseases

Investigating the metabolic functions of the nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma) has been extremely rewarding over the past years. Uncovering the biologic roles of PPARgamma and its mechanism of action has greatly advanced our understanding of the transcriptional control of lipid and glucose metabolism, and compounds such as thiazolidinediones which directly regulate PPARgamma have proven to exhibit potent insulin-sensitizer effects in the treatment of diabetes. We review here recent advances on the emerging role of growth hormone releasing peptides in regulating PPARgamma through interaction with scavenger receptor CD36 and ghrelin GHS-R1a receptor. With the impact that these peptides exert on the metabolic pathways involved in lipid metabolism and energy homeostasis, it is hoped that the development of novel approaches in the regulation of PPAR functions will bring additional therapeutic possibilities to face problems related to metabolic diseases.