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 glycation
Alanine
Ala / A · hydrophobic residue · neutral charge
AOD-9604
is studied as an anti-obesity peptide that can reduce weight gain and increase fat oxidation in obese animal models with generally neutral effects on IGF-1 and glucose metabolism in early human trials
Arginine
Arg / R · basic residue · positive charge
Argireline
is a topical cosmetic peptide reported to decrease dynamic wrinkles by partially mimicking the mechanism of botulinum toxin in a non-invasive manner
Asparagine
Asn / N · polar residue · neutral charge
Aspartic acid
Asp / D · acidic residue · negative charge
BPC-157
is investigated for accelerating healing of gastrointestinal mucosa, tendons, ligaments, bone, and nervous tissue in preclinical models, with anti-inflammatory and pro-angiogenic effects
Comparison
While Humanin exerts neuroprotective and cytoprotective effects in models of Alzheimer’s disease, ischemia, and metabolic stress, reducing apoptosis and improving cell survival7136141, Kisspeptin is a key regulator of the hypothalamic–pituitary–gonadal axis, controlling puberty and fertility; kisspeptin-10 also inhibits trophoblast invasion and tumor metastasis in experimental models339199.
While Humanin works as a mitochondrial-derived 24-amino-acid peptide that protects cells against diverse apoptotic insults by interacting with cell-surface cytokine receptor complexes and intracellular targets, thereby activating pro-survival STAT3 and other pathways7136141, Kisspeptin is a family of peptides (eg, kisspeptin-10, -13, -14, -54) derived from the KISS1 precursor that activate G-protein–coupled receptor KISS1R (GPR54), triggering GnRH release and regulating pubertal onset and reproductive axis activity339199.
Humanin
MT-RNR2
Kisspeptin
KISS1
Both peptides fall into a similar broad context as Neuropeptides, although the details of how they are used and discussed still diverge. Their typical research and application settings separate fairly clearly: Humanin is more often discussed in the realm of Neurology and brain health, Aging and longevity, and Cardiovascular health, whereas Kisspeptin is more often associated with the realm of Reproductive health. Their biological logic is quite different: Humanin is a signaling modulator, whereas Kisspeptin is a receptor agonist. Humanin has a more mitochondrial-encoded origin, while Kisspeptin is closer to natural endogenous background and both are still best understood as being in Preclinical development. Kisspeptin incorporates amidation features that are not part of Humanin.