What Is Ipamorelin?
Ipamorelin is a synthetic peptide classified as a growth hormone secretagogue. It stimulates the production and release of growth hormone (GH) from the pituitary gland, which is responsible for various physiological processes. Ipamorelin works by binding to specific receptors in the hypothalamus and pituitary gland, increasing GH levels.
Its operational mechanics enabled it to stimulate this gland-based secretion related to growth in animal test subjects. What it also enables it to do is inhibit somatostatin; the role of somatostatin is to inhibit the pituitary’s gland ability to secrete growth hormone. Therefore, by inhibiting somatostatin, Ipamorelin demonstrated even more superior growth hormone secretion effects in these rat studies.
Ipamorelin and Negative Corticosteroid Effects
Glucocorticoids are a class of corticosteroids often used for their anti-inflammatory and immunosuppressive effects. While this forms the basis for their action against various diseases, it is also responsible for the long-term side effects that appear with their chronic use or at high doses.
It has also been confirmed that the higher the dose and the longer the duration of glucocorticoid use, the more challenging it becomes to taper off the medication. Several animal studies showed that Ipamorelin offers a promising approach to mitigating the side effects of glucocorticoid therapy.
Ipamorelin and Bone Mineral Density
It is worth noting that long-term usage of glucocorticoids leads to decreased bone density and an increased risk of fractures. A recent study on rats stated that Ipamorelin strongly improved glucocorticoid-reduced periosteal bone formation and muscle strength. That is, in rats treated with both glucocorticoids and Ipamorelin, the rate of bone formation was fourfold higher compared to that of rats treated with glucocorticoids alone.
This study suggests that Ipamorelin could counteract the harmful effects of glucocorticoids on the bone and muscle tissues. Another study also shows that treatment with Ipamorelin significantly increased bone mineral density and improved trabecular thickness and connectivity microarchitectural parameters.
Ipamorelin and Diabetes
Research in rats also shows that Ipamorelin can significantly impact insulin release. Ipamorelin influences insulin release primarily through its effects on growth hormone (GH) and insulin-like growth factor 1 (IGF-1), affecting glucose metabolism and insulin sensitivity.
The pancreas can maintain more stable blood glucose levels with better insulin sensitivity, leading to a more balanced glucose homeostasis.
Ipamorelin and Postoperative Ileus
Postoperative Ileus (POI) refers to the period when bowels start to feel discomfort after surgery. It is a common complication that occurs more frequently after operations on the abdomen. This condition mainly arises from the lack of normal gastrointestinal functions.
The main problem with this surgery is that you will stay at the hospital for a more extended period of time and also take a lot of time to recover. There were studies that confirmed that Ipamorelin has helped accelerate gastrointestinal recovery in patients who have POI. The research also showed that these peptides improved gastrointestinal motility, allowing their patients to tolerate meals better.
Ipamorelin as a Ghrelin Receptor Probe
In the majority of animal (primarily rat) studies, ipamorelin proved itself as a potent ghrelin receptor agonist, which strongly binds to the ghrelin receptors. Since ghrelin receptors proliferate in certain cancers and cardiovascular diseases, researchers have speculated that it can be used as a probe in positron emission tomography (PET) scans, as a way to further verify the diagnosis.
Some in vitro studies set out to test these claims and resulted with positive outcomes, showing that it’s possible, in theory, to use ipamorelin as a PET probe. Of course, these findings need to be confirmed in large-scale animal (later human) studies, but the initial results seem promising.
References:
- K. Raun et al., “Ipamorelin, the first selective growth hormone secretagogue,” Eur. J. Endocrinol., vol. 139, no. 5, pp. 552–561, Nov. 1998.
- N. B. Andersen, K. Malmlöf, P. B. Johansen, T. T. Andreassen, G. Ørtoft, and H. Oxlund, “The growth hormone secretagogue ipamorelin counteracts glucocorticoid-induced decrease in bone formation of adult rats,” Growth Horm. IGF Res. Off. J. Growth Horm. Res. Soc. Int. IGF Res. Soc., vol. 11, no. 5, pp. 266–272, Oct. 2001.
- J. Svensson et al., “The GH secretagogues ipamorelin and GH-releasing peptide-6 increase bone mineral content in adult female rats,” J. Endocrinol., vol. 165, no. 3, pp. 569–577, Jun. 2000.
- E. Adeghate and A. S. Ponery, “Mechanism of ipamorelin-evoked insulin release from the pancreas of normal and diabetic rats,” Neuro Endocrinol. Lett., vol. 25, no. 6, pp. 403–406, Dec. 2004.
- D. E. Beck, W. B. Sweeney, M. D. McCarter, and Ipamorelin 201 Study Group, “Prospective, randomized, controlled, proof-of-concept study of the Ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients,” Int. J. Colorectal Dis., vol. 29, no. 12, pp. 1527–1534, Dec. 2014.
