Comparison

Hexarelin vs SS-31

Function

While Hexarelin is investigated for effects on GH secretion, cardiac protection, and muscle metabolism, with higher GH secretory potency than earlier GHRPs1929, SS-31 improves mitochondrial bioenergetics, reduces oxidative stress, and shows protective effects in models of ischemia-reperfusion, neurodegeneration, and other mitochondrial disorders4637137.

Mechanism

While Hexarelin works as a potent synthetic hexapeptide (examorelin) that agonizes GHSR-1a to stimulate GH release and also binds CD36, influencing cardiovascular and metabolic pathways19212996, SS-31 is a mitochondria-targeted tetrapeptide, d-Arg-dimethylTyr-Lys-Phe-NH2, that selectively binds cardiolipin in the inner mitochondrial membrane, stabilizing cristae structure, improving electron transport, and reducing ROS production4637137143.

Length and Sequence

Hexarelin is 6 amino acids long, whereas SS-31 is shorter as it has a length of 4 amino acids. Hexarelin is made up of a sequence of Histidine, Tryptophan, Alanine, Tryptophan, Phenylalanine, Lysine. SS-31 is made up of a sequence of Arginine, dimethylTyr, Lysine, Phenylalanine.

Receptor

Hexarelin

Primary: GHSR-1a (ghrelin receptor); also binds the scavenger receptor CD36 in vascular and macrophage tissues192129

SS-31

Cardiolipin-rich inner mitochondrial membrane; interacts with cardiolipin and associated mitochondrial proteins rather than a classical cell-surface receptor46137143

Organism or Origin

Hexarelin

Fully synthetic growth hormone secretagogue29

SS-31

Fully synthetic Szeto–Schiller tetrapeptide; not encoded in the genome4637

Gene

Hexarelin

GHSR

SS-31

Not assigned in the current dataset.

Related articles

No related articles are linked to these peptides yet.

Sources

19Identification of the growth hormone-releasing peptide binding site ..., https://pmc.ncbi.nlm.nih.gov/articles/PMC1133797/
21Hexarelin Peptide | Strength & Recovery - Paragon Sports Medicine, https://www.paragonsportsmedicine.com/peptides/hexarelin
29Examorelin - Wikipedia, https://en.wikipedia.org/wiki/Examorelin
96Growth Hormone Secretagogue Receptor - ScienceDirect.com, https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/growth-hormone-secretagogue-receptor
46Discovery of novel SS-31 (d-Arg-dimethylTyr-Lys-Phe-NH2 ... - PMC, https://pmc.ncbi.nlm.nih.gov/articles/PMC11409442/
56Discovery of novel SS-31 (d-Arg-dimethylTyr-Lys-Phe-NH2 ..., https://pubs.rsc.org/en/content/articlelanding/2024/ra/d4ra05517a
137Mitochondrial protein interaction landscape of SS-31 | PNAS, https://www.pnas.org/doi/10.1073/pnas.2002250117
143SS-31 Peptide: Mitochondrial Repair for Energy and Longevity, https://revolutionhealth.org/blogs/news/peptide-therapy-ss-31