Scientific Reference
Sermorelin
Evidence profile: Predominantly preclinical
Sermorelin is a synthetic 29-residue peptide reproducing the N-terminal segment of human growth hormone-releasing hormone (GHRH). Native GHRH has 44 residues, and the 1–29 segment, amidated at its C-terminus as here, is reported to retain the receptor activity of the full hormone. Like native GHRH, it is cut quickly by plasma enzymes including dipeptidyl peptidase-4, a property that later analogues such as tesamorelin were modified to avoid. Research on it has centred on growth hormone release from the anterior pituitary, including human physiology studies, many of them decades old, alongside animal and cell work. Recent literature on sermorelin itself is sparse beside that on newer GHRH analogues.
Mechanism of Action
Sermorelin binds the GHRH receptor, a class B G-protein-coupled receptor on somatotroph cells of the anterior pituitary. Receptor activation has been reported to raise cyclic AMP and activate protein kinase A and the transcription factor CREB, which is linked to transcription of the growth hormone gene as well as to release of stored hormone. Because it acts upstream of the pituitary, the growth hormone released stays subject to inhibition by somatostatin and to negative feedback from IGF-1. This is the main pharmacological difference between GHRH analogues and growth hormone itself.
Molecular Information
- Type: GHRH analog (growth hormone secretagogue)
- Length: 29 amino acids
- Molecular weight: 3357.9 g/mol
- Molecular formula: C149H246N44O42S
- CAS: 86168-78-7