Growth hormone-releasing activity of hexarelin, a new synthetic hexapeptide, before and during puberty.
Bellone. J J; Aimaretti. G G; Bartolotta. E E; Benso. L L; Imbimbo. B P BP; Lenhaerts. V V; Deghenghi. R R; Camanni. F F; Ghigo. E E
Key Findings
- A 2 µg/kg IV dose of hexarelin caused a larger GH rise than a 1 µg/kg IV dose of GHRH.
- Increasing the IV dose to 2 µg/kg produced a stronger GH response than a 1 µg/kg dose.
- A 10 mg oral dose of hexarelin still raised GH more than IV GHRH in a small group.
- Pubertal children, especially girls, showed a greater GH increase than pre‑pubertal kids.
Practical Outcomes
- Hexarelin appears to be a very potent GH secretagogue, with clear dose‑response effects and even oral activity. For biohackers this suggests it could be used to boost GH, but the data are limited to children, so adult dosing, safety, and long‑term effects remain unknown. Caution and further research are needed before applying these findings to adult protocols.
Summary
Hexarelin, a synthetic six‑amino‑acid peptide, makes the body release a lot of growth hormone (GH). In kids it worked better than the natural GH‑releasing hormone, especially at higher doses, and even an oral pill gave a boost. The GH surge was bigger during puberty and was strongest in girls.
Abstract
The objective of this study was to verify the GH-releasing activity of a synthetic hexapeptide, hexarelin (HEX), before and during puberty. Ninety-six children (54 boys and 42 girls, aged 4.1-17.4 yr) were studied. Fifty-two of the children were prepubertal, and the other 44 were in pubertal stage II-IV. The GH response to 2 micrograms/kg HEX, iv (n = 56), was higher (P < 0.001) than that induced by 1 microgram/kg GHRH, iv (n = 33). The iv dose of 2.0 micrograms/kg HEX induced a greater GH increase (P < 0.02) than the 1.0 microgram/kg dose. The GH-releasing effect of 10 mg HEX, orally, was greater (P < 0.03) than that of 1.0 microgram/kg GHRH, iv (n = 7). The iv dose of 2 micrograms/kg HEX elicited an increase in GH levels that was higher in pubertal children than in prepubertal children (77.5 +/- 8.5 vs. 39.4 +/- 4.4 micrograms/L; P < 0.001). Before puberty, there was no sex-dependent difference in the GH response to HEX. It increased during puberty (P < 0.05 and P < 0.002 for boys and girls, respectively), when it was higher (P < 0.05) in girls than in boys. In contrast, GH responses to GHRH were not related to sex differences and/or puberty. In conclusion, HEX is a potent and reproducible stimulus of GH secretion in children. The effect of HEX increases in puberty, with girls showing a more marked GH response.
Study Information
pubmed
1995
10.1210/jcem.80.4.7714074