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, GHRP-2 is used in research to induce robust GH pulses and study anabolic and metabolic effects; clinically developed as pralmorelin for GH deficiency diagnostics6272.
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, GHRP-2 is a second-generation hexapeptide growth hormone–releasing peptide that mimics ghrelin by agonizing GHSR-1a, strongly stimulating pulsatile GH release and modestly raising prolactin, ACTH, and cortisol62723096.