Ipamorelin Research

1. Ipamorelin and Negative Corticosteroid Effects

Glucocorticoids, the class of corticosteroids commonly used to treat inflammation in conditions ranging from cancer to autoimmune disease, have a host of serious side effects that often limit their usefulness. Mitigating the side effects of glucocorticoids could provide for higher dosing of these medications and allow people to remain on them for longer periods of time, both of which could have positive benefits on morbidity and mortality. Ipamorelin has been shown, in several studies, to reduce or even reverse the side effects of glucocorticoid use.

2. Ipamorelin and Bone Health

One of the most profound problems associated with long-term glucocorticoid use is loss of bone density and subsequent risk of fracture. Current therapies include bisphosphonates, hormone therapies, and new monoclonal antibodies. All of these are effective treatments in their own rights, but they also all have side effects, limited efficacy, or high cost. Ipamorelin, on the other hand, is relatively inexpensive to produce and has a very limited number of side effects. Studies in rats indicate that ipamorelin can completely stop bone loss due to corticosteroids and even leads to a four-fold increase in bone formation in rats exposed to these drugs^[2]. Further studies indicate that ipamorelin also increases bone mineral density systemically, thereby increasing the strength of both existing bone and newly formed bone^[3]. As an added bonus, ipamorelin helps to offset some of the other side effects of steroids, such as muscle wasting and increased visceral fat deposition.

3. Ipamorelin and Muscle Growth

There is evidence to suggest that GH and growth hormone secretagogues like ipamorelin may reduce the catabolic effects that glucocorticoids have on muscle. Research in rats given glucocorticoids shows a decrease in nitrogen wasting in the liver and improved nitrogen balance following administration of ipamorelin^[4]. Muscle wasting is one of the primary side effects associated with glucocorticoid use and a common treatment-limiting side effect. The ability to counteract muscle catabolism and bone-density loss with a single drug could be hugely beneficial to patients who require glucocorticoids.

4. Ipamorelin and Diabetes

Research in diabetic rats has revealed that ipamorelin can potentiate insulin release. This effect is most likely a result of indirect stimulation of the calcium channel found on pancreatic islet cells where insulin is made and stored^[5]. Ipamorelin’s actions on the pancreas may help us better understand the functional limitations of type 2 diabetes and lead to the development of novel therapeutics or even preventative measures.

5. Studied for Treatment of Post-Operative Ileus

Post-operative ileus (POI) is a common condition that follows certain types of surgery, but is particularly common following abdominal surgery. The condition is characterized by an inability of individuals to take oral nutrition because the GI system ceases to function. It can be characterized by pain, but the primary problem with POI is that it slows discharge from the hospital and lengthens overall recovery time.

Ipamorelin has been investigated in several proof-of-concept clinical trials to determine if administration of the peptide can reduce POI. The research suggests that ipamorelin does shorten time to first meal by approximately 12 hours^{[6], [7]}. Unfortunately, and despite early limited success, the trials were abandoned when the company conducting them decided that efficacy was not high enough to create a viable product. There is hope that ongoing research can boost efficacy or that research into combination therapies that include ipamorelin can find a synergistic effect with other compounds that will render the therapy more effective.

Source: PubMed

1. Amount of radiolabeled food remaining in stomach is lower in rats with POI after ipamorelin administration, even when compared to rats not suffering from POI.
2. The geometric location of the food is similar to rats without POI when rats with POI are given ipamorelin.
3. Location of radiolabeled food is more distal in GI tract, and similar to rats without POI, after ipamorelin is administered.

6. Ipamorelin as Ghrelin Receptor Probe

Ipamorelin is a selective ghrelin receptor agonist and binds strongly to the ghrelin receptor. The ghrelin receptor is known to increase in abundance in certain types of cancer (e.g. human carcinomas) and heart failure. Given these facts, researchers recently speculated that ipamorelin could be used as a probe in positron emission tomography (PET) as an aid to diagnosis. Basic in vitro studies have demonstrated the feasibility of this approach and have confirmed that ipamorelin^[8], which is easy to synthesize in a lab, could theoretically be used as a PET probe. The next step is to test the probe to determine how well it functions in vivo and to develop standards for interpreting PET studies done with it.

Ipamorelin Is Neglected in Research

Though ipamorelin does not have orphan-drug status at this time, it is still a neglected drug in research settings. Despite promising early studies, interest in ipamorelin has waned following the decision not to pursue it as a treatment for post-operative ileus. Ipamorelin has a number of benefits to offer, not just as a therapeutic, but as a tool for better understanding a number of disease states and their physiologic impacts. Ipamorelin will likely be of interest in research again, once someone jump-starts the field with new data and cutting-edge insight into the benefits of this unique peptide.

Ipamorelin Resources

• [1] K. Raun et al., “Ipamorelin, the first selective growth hormone secretagogue,” Eur. J. Endocrinol., vol. 139, no. 5, pp. 552–561, Nov. 1998. [PubMed]
• [2] 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. [PubMed]
• [3] 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. [PubMed]
• [4] N. K. Aagaard et al., “Growth hormone and growth hormone secretagogue effects on nitrogen balance and urea synthesis in steroid treated rats,” Growth Horm. IGF Res. Off. J. Growth Horm. Res. Soc. Int. IGF Res. Soc., vol. 19, no. 5, pp. 426–431, Oct. 2009. [PubMed]
• [5] 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. [PubMed]
• [6] 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. [PubMed]
• [7] B. Greenwood-Van Meerveld, K. Tyler, E. Mohammadi, and C. Pietra, “Efficacy of ipamorelin, a ghrelin mimetic, on gastric dysmotility in a rodent model of postoperative ileus,” J. Exp. Pharmacol., vol. 4, pp. 149–155, Oct. 2012. [PubMed]
• [8] M. M. Fowkes, T. Lalonde, L. Yu, S. Dhanvantari, M. S. Kovacs, and L. G. Luyt, “Peptidomimetic growth hormone secretagogue derivatives for positron emission tomography imaging of the ghrelin receptor,” Eur. J. Med. Chem., vol. 157, pp. 1500–1511, Sep. 2018. [Science Direct]