Tesamorelin: A Stabilised GHRH Analog
Tesamorelin belongs to the same family as CJC-1295 and sermorelin — all are engineered forms of growth hormone-releasing hormone — but it takes a different approach to the same stability problem.
The parent sequence
Native GHRH is a 44-residue peptide. The first 29 residues carry full receptor activity, which is why several analogs are built on GHRH(1-29). Tesamorelin is unusual in retaining the full 44-residue length rather than truncating.
The modification
A trans-3-hexenoyl group is attached at the N-terminus. The N-terminal region is where dipeptidyl peptidase-4 cleaves, so occupying it with an acyl group blocks the principal degradation route while leaving the receptor-binding determinants intact.
This is a different strategy from the two other common approaches. CJC-1295 uses amino acid substitutions to resist cleavage, optionally combined with an albumin-binding group; sermorelin is essentially unmodified GHRH(1-29) and is correspondingly short-lived. Comparing the three is a clean illustration of how the same stability problem admits several solutions — see peptide half-life and how analogs extend it.
Why the distinction matters experimentally
GHRH receptor signalling is pulsatile in vivo. Analogs with different exposure profiles therefore probe different questions, and an experimental design written for one is not transferable to another. Treating GHRH analogs as an interchangeable class is the most common design error in this area.
Literature: PubMed and the broader GHRH analog literature.
Handling
At 44 residues tesamorelin is longer than most peptides in a research catalogue, and longer sequences are more prone to aggregation on reconstitution. Add solvent gently down the vial wall, allow the cake to wet before mixing, and avoid vortexing or sonication. See choosing a reconstitution solvent.
Product: Tesamorelin 10mg; related compounds in growth hormone peptides, and background in GHRH analogs vs secretagogues.
ExoLabz supplies compounds for laboratory research use only. Nothing on this page is medical advice or a suggestion of human or veterinary use. Certificates of analysis are published on this site.
