Scientific Reference
Sermorelin
Evidence profile: Preclinical, with limited uncontrolled human reports
Sermorelin is a synthetic peptide of 29 amino acids that reproduces the front end of human growth hormone-releasing hormone (GHRH). The natural hormone has 44 residues, and the 1-29 segment, with an amidated C-terminus as here, is reported to keep the receptor activity of the whole. Like the hormone itself it is cut rapidly by plasma enzymes including dipeptidyl peptidase-4, a vulnerability that later analogues such as tesamorelin were modified to avoid. Research has centred on growth hormone release from the anterior pituitary, including human physiology studies, many decades old, together with animal and cell work. Recent literature on sermorelin itself is sparse beside that for newer GHRH analogues.
Mechanism of Action
Sermorelin binds the GHRH receptor, a class B G-protein-coupled receptor on pituitary somatotrophs. Activation is reported to raise cyclic AMP and engage protein kinase A and the transcription factor CREB, which is tied to transcription of the growth hormone gene as well as release of stored hormone. Because it works upstream of the pituitary, the growth hormone that is released remains subject to inhibition by somatostatin and to negative feedback from IGF-1. That is the central pharmacological contrast between GHRH analogues and growth hormone itself.
Molecular Information
- Type: GHRH analog (growth hormone secretagogue)
- Molecular weight: 3357.9 g/mol
- Molecular formula: C149H246N44O42S
- CAS: 86168-78-7