Function
While Acetyl tetrapeptide-5 is used in cosmetic eye formulations to decrease puffiness, eye bags, and dark circles by reducing edema and protecting proteins such as SOD from glycation51150159154, Hexarelin is investigated for effects on GH secretion, cardiac protection, and muscle metabolism, with higher GH secretory potency than earlier GHRPs1929.
Mechanism
While Acetyl tetrapeptide-5 works as a synthetic tetrapeptide, Ac-βAla-His-Ser-His (Eyeseryl), with reported ACE-1 inhibition and anti-glycation activity, proposed to improve microcirculation and reduce capillary permeability and fluid accumulation in periorbital tissues51150159157, Hexarelin is a potent synthetic hexapeptide (examorelin) that agonizes GHSR-1a to stimulate GH release and also binds CD36, influencing cardiovascular and metabolic pathways19212996.