Ziconotide

Pentadecapeptide almost always means BPC-157, a synthetic 15-amino-acid chain (Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val) derived from a protein found in human gastric juice. It is one of the most hyped 'healing' peptides online, marketed for tendon, gut, and muscle repair, but here is the catch: essentially all of the supporting evidence is from rats and mice. There is no FDA approval and no completed human clinical trial proving it does any of this.

Dermorphin is a seven-amino-acid opioid peptide (Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2) first found in the skin of South American Phyllomedusa frogs. It is a strong, highly selective mu-opioid agonist, the same receptor morphine and fentanyl hit, and in mouse brain-injection studies it was hundreds of times more potent than morphine. It is not approved anywhere for human use. Its main claim to fame is doping: it was caught in dozens of American racehorses in 2012, where it was nicknamed 'frog juice'. This is an opioid, and it should be treated like one.

Teduglutide is a 33-amino-acid GLP-2 analog approved for short bowel syndrome (SBS) in people who depend on IV nutrition or fluids. GLP-2 is the gut's own growth signal, and teduglutide makes the remaining intestine grow taller villi and absorb more, so some patients can cut back the hours they spend hooked to a drip. The FDA approved it as Gattex in December 2012 (children 1 year and older were added in 2019), and in Europe it is sold as Revestive. It works, but it is a serious daily injection with real monitoring requirements, not a gut-health supplement.

BPC-157 is a synthetic 15-amino-acid peptide (sequence Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val) based on a fragment of a protective protein found in human gastric juice. It is studied almost entirely in animals for tendon, ligament, gut, and tissue healing, and it has racked up hundreds of preclinical papers. The catch: it is not approved by any regulator for any use, and the human evidence is a handful of small pilot studies, not real clinical proof.

TB-500 is a synthetic peptide that copies the active region of thymosin beta-4, a natural protein that controls how cells build and move their internal skeleton. Most TB-500 products reproduce the short LKKTETQ sequence (residues 17 to 23) responsible for binding actin and driving cell migration, which is why it gets marketed for tendon, muscle, and wound repair. Here is the honest part: there are essentially no completed human trials of the TB-500 fragment itself, and almost all the human clinical data is for the full-length thymosin beta-4 molecule, which is related but not the same thing.

Thymosin beta-4 (Tbeta4) is a small 43 amino acid peptide found in nearly every cell in the body, originally isolated from the thymus. Its main job is binding and sequestering G-actin, the building block of the cell's internal scaffolding, which lets it influence cell movement, wound repair, and tissue regeneration. It is researched heavily for healing of skin, cornea, and heart tissue, but it is not an FDA-approved drug. (The injectable sold as TB-500 is a synthetic fragment marketed as related to Tbeta4, not the full natural peptide.)