Mechanism of action: Glucagon-like peptide-1 receptors in skin biology.

This review provides an overview of current evidence on the presence, distribution, and physiologic role of glucagon-like peptide-1 receptors in skin tissue. Although glucagon-like peptide-1 receptor agonists are primarily used to treat type 2 diabetes mellitus and obesity, growing evidence suggests they may also directly affect the skin. It includes available research on glucagon-like peptide-1 receptor expression in major skin cell types, including keratinocytes, dermal fibroblasts, and the cutaneous microvascular endothelium. The strength of the evidence is evaluated according to the species studied, the experimental model used, and the method of receptor detection, including gene expression, protein identification, and functional activity. Differences in findings across animal models, cultured cells, and human tissue are also considered. In addition, this review distinguishes between skin effects likely mediated by direct activation of glucagon-like peptide-1 receptors in cutaneous tissue and those that occur indirectly through systemic metabolic improvement or modulation of immune and inflammatory pathways.