The distinct blue color of GHK-Cu comes from the copper ion (Cu) that is chelated, or bound, to the GHK peptide chain
Some examples of GLP receptor agonists include exenatide (Byetta, Bydureon), liraglutide (Victoza, Saxenda), semaglutide (Ozempic, Wegovy) and tirzepatide (Zepbound, Mounjaro)
When these nutrients make contact with L-cells, they trigger a cascade of cellular signals that result in GLP-1 synthesis and secretion
Klein S, Fontana L, Young VL, Coggan AR, Kilo C, Patterson BW, et al
doi: 10.3390/nu8020078 125 PapucC.GoranG
Important safety considerations include a boxed warning regarding thyroid C-cell tumors observed in rodents (though the relevance to humans is unknown) and contraindications for patients with a personal or family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN2)