Sermorelin (Peptides)

Sermorelin acetate (Growth Hormone-Releasing Hormone - GHRH) is a synthetic version of a naturally occurring substance that stimulates the release of growth hormone (GH). Produced within and secreted by the pituitary gland, growth hormone is necessary for childhood growth and development. Primarily administered to children who fail to thrive (grow normally), because their bodies do not produce enough growth hormone, Sermorelin may be used to elevate and restore normal GH levels in deficient patients.

Background

When the structure of GHRH was first described by the Nobel Laureates, R. Guilleman and A. Shalley in the 1970’s one of their students, William Wehrenberg sought to determine which part of the molecule was essential for its pituitary stimulating action. By eliminating individual amino acids and then testing the remaining peptide, he found that only the first 29 amino acids are responsible for stimulating pituitary production and the secretion of HGH. Consequently, the chemical name for Sermorelin is GRH 1-29 NH2. The NH2 is included in the name so as to indicate the amino terminus of the molecule.

More specifically, sermorelin acetate is the acetate salt of an amidated synthetic 29- amino acid peptide (GRF 1-29 NH 2) that corresponds to the amino-terminal segment of the naturally occurring GHRH (or GRF) consisting of 44 amino acid residues. The free base of sermorelin has the empirical formula C 149 H 246 N 44 O 42 S and a molecular weight of 3,358 daltons. Sermorelin is a sterile, non-pyrogenic, lyophilized powder intended for subcutaneous injection after reconstitution with Bacteriostatic Water for Injection and should be stored at between 36 and 46 °F (2 and 8 °C). As for its taxonomy, Sermorelin is listed as an organic compound (kingdom), an organic acid (superclass), a carboxylic acid (class), amino acid/peptide; analogue (subclass), and as a peptide (direct parent).

Sermorelin Indications

Sermorelin is available in varying milligram dosages. Sermorelin is officially indicated and approved for diagnostic evaluation of pituitary function and also for increasing growth in children. Sermorelin has many off label usages including acute or age-related growth hormone insufficiency such as dwarfism, as well as in the prevention of HIV-induced weight loss. It works by increasing plasma growth hormone (GH) concentrations through stimulating the pituitary gland to release GH. More specifically, Sermorelin binds to the growth hormone releasing hormone receptor and mimics native GRF in its ability to stimulate growth hormone secretion.

Numerous clinical studies have demonstrated Sermorelin’s multifaceted properties, some of which are cited here:

  • Sermorelin maintains bioactivity in vitro and is almost equally effective in eliciting secretion of endogenous growth hormone in vivo.
  • Sixteen prepubertal children who were insufficient for growth hormone were treated with growth hormone releasing hormone (GHRH) 1-40 and GHRH 1-29 for a mean time of nine months (range 6-12 months) with each peptide. Response to conventional growth hormone treatment in a matched group of children was significantly better than the response after GHRH. A significant improvement in height velocity was observed in the children transferred to growth hormone replacement.
  • Six short children with low 24-hour growth hormone (GH) secretion were treated with continuous subcutaneous infusion of GHRH (1-29)NH2 for 3 weeks using a portable infusion pump. Plasma levels of GHRH (1-29)NH2 were significantly higher on day 21 than on day 1 of treatment, suggesting altered pharmacokinetics over time.
  • GH response to GHRH-arginine testing is reduced in both overweight and obese subjects and negatively associated with indices of central abdominal obesity including WC, trunk fat, and visceral adipose tissue. The use of waist circumference, as a surrogate for central adiposity, adds predictive information to the determination of GH response, independent of BMI.
  • Peak responses to GHRH analogs occurred at 15 or 30 min. An increase in the integrated plasma growth hormone (GH) response was observed at each dose.
  • Sermorelin inhibits cancer cell lines human breast cancer cell lines, LNCaP prostate cancer cell line as well as in NCI H838 non-small cell lung carcinoma.
  • Assessment of quality of life parameters [during Sermorelin use] revealed a significant improvement in general well-being (P < 0.05) and libido (P < 0.01) in men.