Ipamorelin maintained its GH-releasing ability and growth-promoting effects in rats receiving methylprednisolone, overcoming the typical GH suppression caused by glucocorticoid treatment.
Steroid-resistant GH releaseIpamorelin maintained its GH-stimulating effect despite methylprednisolone treatment that typically suppresses GH
What the researchers found
Ipamorelin maintained GH-releasing activity during 8 days of methylprednisolone treatment in rats and partially preserved longitudinal bone growth over 15 days despite glucocorticoid-induced growth suppression.
Why it matters
Children on chronic steroids (for asthma, autoimmune diseases, transplants) often fail to grow properly. A GH secretagogue that works despite steroids could preserve their growth and development.
How the study worked
Two animal experiments in rats: (1) GH release after ipamorelin with/without 8-day MP treatment, (2) 15-day bone growth study with ipamorelin during MP administration. Plasma GH and tibial bone growth measured.
What this study cannot tell us
Rat study. Bone growth was only partially preserved, not fully restored. The mechanism by which ipamorelin bypasses glucocorticoid suppression was not determined. Human pediatric data needed.
How to read the evidence
Preliminary animal evidence with clinically relevant experimental design (GH secretagogue during steroid treatment), but limited to rats.
When this study was published
Published in 1999. The concept of using GH secretagogues to counteract steroid-induced growth suppression remains clinically relevant.
The bigger picture
Steroid-induced growth suppression is a major pediatric problem. If ipamorelin can bypass the GH-suppressive effects of steroids, it could be combined with steroid therapy to protect growth in the millions of children who need chronic glucocorticoids.
Questions still open
- Could ipamorelin prevent growth stunting in children on chronic steroids?
- Does ipamorelin bypass somatostatin-mediated GH suppression by steroids?
- What is the optimal ipamorelin dose to counteract steroid growth suppression?
Common questions
Why do steroids stunt growth?
Could ipamorelin help these children?
Read the original research
Methylprednisolone does not inhibit the release of growth hormone after intravenous injection of a novel growth hormone secretagogue in rats.
Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society, 9(6), 445-50
Citation
Malmlöf, K; Johansen, P B; Haahr, P M; Wilken, M; Oxlund, H. (1999). Methylprednisolone does not inhibit the release of growth hormone after intravenous injection of a novel growth hormone secretagogue in rats.. Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society, 9(6), 445-50.