Exendin-4 (acetate)

Exendin-4 acetate (Exenatide acetate), a 39 amino acid peptide, is a long-acting glucagon-like peptide-1 receptor agonist with an IC₅₀ of 3.22 nM. IC50 & Target: IC50: 3.22 nM (glucagon-like peptide-1 receptor)^[1] In Vitro: In human umbilical vein endothelial cells, Exendin-4 significantly increases NO production, endothelial NO synthase (eNOS) phosphorylation, and GTP cyclohydrolase 1 (GTPCH1) level in a dose-dependent manner^[2]. Exendin-4 shows cytotoxic effects to MCF-7 breast cancer cells with IC₅₀ of 5 μM at 48 hour^[3]. In Vivo: Both low- and high-dose Exendin-4 treatment in ob/ob mice improve serum ALT and reduce serum glucose, and calculated HOMA scores compared with control. Exendin-4-treated ob/ob mice sustain a marked reduction in the net weight gain in the final 4 weeks of the study period^[4]. Animals treated with Exendin-4 have more pancreatic acinar inflammation, more pyknotic nuclei and weigh significantly less than control rats. Exendin-4 treatment is associated with lower leptin levels as well as lower HOMA values in rats^[5]. Exenatide causes dose-dependent relaxation of rat thoracic aorta, which is evoked via the GLP-1 receptor and is mediated mainly by H₂S but also by NO and CO^[6].