Proxofim Peptide and Cellular Apoptosis: A Research Summary

Proxofim Peptide and Cellular Apoptosis: A Research Summary

FOXO4-D-Retro-Inverso (FOXO4-DRI), also called Proxofim peptide, is a synthetic variant of the endogenous FOXO4 protein. This synthetic variant is developed with D-amino acids in place of the endogenously occurring L-amino acids.[1] This modification was made in the hope of supporting stability by reducing susceptibility to proteolytic degradation, thereby increasing the potential to extend a cellular lifespan.

Despite these structural alterations, FOXO4-DRI appears to retain an ability to modulate transcription and cellular signaling pathways. As a retro-inverso peptide, researchers report that it mirrors the structural topology of the native peptide while exhibiting potentially more robust resistance to enzymatic breakdown.

Retro-inverso peptides, such as FOXO4-DRI, are synthesized by reversing the amino acid sequence and altering the chirality of the peptide backbone. This design appears to confer several advantages, including possible prolonged stability and preserved bioactivity. Due to their structural resilience, these peptides have been explored in various biological contexts, particularly in understanding protein-protein interactions.

 

Mechanism of Action

FOXO4-DRI is believed to function by modulating the interaction between the FOXO4 protein and the tumor suppressor protein p53.

Under normal conditions, FOXO4 is suggested to bind to p53, thereby inhibiting its role in promoting apoptosis. However, FOXO4-DRI is thought to disrupt this interaction by potentially competitively binding to p53. It is believed that this reduces instances of FOXO4 successfully exerting its regulatory effects. This disruption facilitates p53-mediated apoptosis and is thought to selectively target senescent cells— particularly those that have lost their functional capacity due to cellular aging.[2]

The selective elimination through immune and waste removal biological systems that impact senescent cells through FOXO4-DRI-mediated apoptosis is thought to contribute to improved cellular turnover and tissue homeostasis. Research suggests that this process may support overall cellular function by removing old or dysfunctional cells, allowing for the proliferation of more functional cells. This mechanism has been a focal point for researchers studying the potential role of FOXO4-DRI in modulating cellular senescence.

 

Scientific Research and Studies

 

Proxofim Peptide and Cellular Senescence

The FOXO4 protein is considered to play a crucial role in maintaining the viability of senescent cells by preventing the tumor suppressor protein p53 from binding to DNA and initiating apoptosis. Proxofim is hypothesized to disrupt this interaction and is thought to allow the engagement of p53 with DNA and promote the selective elimination of senescent cells. This process, often described as the rejuvenation of biological systems, is believed to support cellular homeostasis by facilitating the clearance of dysfunctional cells.[3]

Elimination of senescent cells may lead to a redistribution of metabolic resources toward functional cells, potentially supporting cellular growth, maintenance, and function. While Proxofim does not appear to halt the senescence process entirely, research suggests it may mitigate FOXO4-mediated cellular aging and may thereby decelerate the accumulation of non-functional cells. The biological process of senescence is impacted by various intrinsic and extrinsic factors, which may have contributed to cellular apoptosis or the secretion of inflammatory mediators implicated in cellular aging and cellular age-related pathologies.

 

Proxofim Peptide and Cellular Healthspan

Cellular aging is characterized by the progressive accumulation of irreparable cellular damage, which ultimately diminishes the healthspan of the cell—the period during which cells maintain optimal function. Distinct from lifespan, which denotes the total duration of life, healthspan is a critical determinant of physiological function. Proxofim is proposed to modulate cellular senescence by mitigating the adverse impacts of FOXO4 signaling, thereby preserving cellular integrity and function. While the peptide’s impact on overall lifespan remains inconclusive, its potential role in supporting cellular function and delaying cellular age-associated deterioration warrants further investigation.

A 2017 study conducted on aging cells of murine research models explored the impacts of Proxofim on physiological parameters. Murine models receiving the peptide appeared to exhibit improvements in physical endurance, renal function, and hair density compared to the control group. Although no significant extension in cellular lifespan was observed, the findings suggest that Proxofim may contribute to better-supported tissue function and a reduction in cellular age-associated dysfunction.

Furthermore, research by Baar et al. (2017) highlights the broader implications of FOXO4-DRI analogs. The research states the following about cells observed in laboratory settings;

“independent of aging and age-related diseases, FOXO4-DRI may be useful against the progression, stemness, and migration of cancer. Given that SASP factors influence these, it will be particularly interesting to determine whether FOXO4-DRI affects those p53-wt cancer cells that have adopted a more migratory and stem-like state due to reprogramming by chronic SASP exposure. In any case, the here reported beneficial effects of FOXO4-DRI provide a wide range of possibilities for studying the potential of … removal of senescence against diseases for which few options are available.”[4]

 

Proxofim Peptide and Cardiovascular Function

Cellular age-related decline in proteasome activity has been associated with an increased risk of cardiovascular disorders. The proteasome enzyme reportedly plays a critical role in maintaining cellular homeostasis by facilitating the degradation of damaged or dysfunctional proteins. Research suggests that reduced proteasome activity may contribute to the accumulation of senescent cells, which may negatively impact cardiovascular function as cells age.[5]

The FOXO4 protein is considered to be a key regulator of proteasome activity; however, its endogenous function may be insufficient in mitigating cellular damage associated with cellular aging. Preliminary findings suggest that the Proxofim peptide may support the selective clearance of senescent cells, thereby potentially impacting cellular age-related cardiovascular processes.[6] While these insights provide a foundation for further investigation, additional studies are required to elucidate the precise mechanisms and potential implications of Proxofim in cardiovascular function.

 

Proxofim Peptide and Insulin Signaling Regulation

Research[7] suggests that FOXO proteins may be critical regulators of the insulin signaling pathway. These proteins may play a role in the regulation of cellular metabolism, cell cycle progression, oxidative stress responses, and cellular senescence. Dysregulation of FOXO protein expression has been correlated in studies with pathological conditions, including metabolic disorders, oncogenesis, and premature death of cells. Altered FOXO activity is particularly relevant in insulin resistance and diabetes, where disruptions in insulin signaling are said to contribute to hyperlipidemia and hyperglycemia. This may, in some way, increase the risk of vascular complications, nephropathy, and other metabolic dysfunctions.

While further investigation is required to elucidate the precise mechanisms, preliminary studies suggest that Proxofim peptide may modulate insulin signaling by impacting downstream metabolic pathways. Research suggests that this interaction could contribute to improved glucose homeostasis by mitigating excessive blood glucose accumulation. By modulating FOXO-associated pathways, Proxofim may hold the potential to address metabolic imbalances linked to insulin resistance.

 

Proxofim and Cellular Age-Related Male Hypogonadism

Cellular age-related male hypogonadism, also referred to by researchers as late-onset hypogonadism (LOH), is characterized by a progressive decline in serum testosterone levels. The condition is often accompanied by reduced libido, dysfunction with the physical ability to mate, increased adiposity, and disturbances in behavioral patterns. This decline is said to be primarily associated with the dysfunction of senescent Leydig cells, which reside in the interstitial compartment of the testes. Leydog cells are considered to play a crucial role in testosterone biosynthesis.

A recent in vitro study[8] studied the potential impacts of Proxofim peptide on senescent Leydig cells. The study exposed peptides to a cellular model in which Leydig cells, previously isolated from male murine models, were induced into a senescent state through hydrogen peroxide exposure. Findings suggested that FOXO4 protein plays a role in maintaining the viability of these senescent cells by mitigating apoptosis. Exposure to Proxofim peptide appeared to disrupt FOXO4 activity and may facilitate p53-mediated apoptosis, thereby selectively eliminating dysfunctional Leydig cells.

Subsequent studies in endogenously aged murine cell cultures further supported these observations. Proxofim peptide exposure was associated with improved Leydig cell function, better-supported testicular function, and increased testosterone secretion. These findings suggest that Proxofim peptide may hold potential as a targeted approach for addressing cellular senescence in Leydig cells and mitigating the physiological effects of cellular age-related hypogonadism. Further research is necessary to elucidate its precise mechanisms and broader implications.

 

Proxofim and Neurodegenerative Pathophysiology

Cellular age-related cognitive decline is a multifactorial process, and the precise mechanisms underlying neurodegenerative disorders, such as Alzheimer’s disease, remain incompletely understood. Research[9] suggests that alterations in proteasome enzyme activity may contribute to neurodegeneration, as proteasomal function declines with cellular age. This enzymatic downregulation has been observed in conditions such as Parkinson’s disease, Alzheimer’s disease, and prion-related disorders. However, it remains unclear whether this reduction in proteasome activity is a causative factor or a secondary consequence of disease progression.

Emerging studies[10] suggest that FOXO transcription factors exhibit altered expression patterns in the central nervous system of individuals affected by neurodegenerative disorders. Given the regulatory role of FOXO proteins in cellular homeostasis, it has been hypothesized that exogenous FOXO-modulating peptides, including Proxofim, may help restore FOXO equilibrium and mitigate neurodegenerative processes. However, further research is necessary to elucidate the extent of this potential intervention.

Scientific reports suggest that:

Forkhead box O (FoxO) transcription factors have been implicated in the mechanisms regulating aging and longevity. The functions of FoxOs are regulated by diverse post-translational modifications (e.g., phosphorylation, acetylation, ubiquitination, methylation, and glycosylation). FoxOs exert both detrimental and protective effects on NDDs (Neurodegenerative diseases). Therefore, an understanding of the precise function of FoxOs in NDDs will be helpful for developing appropriate treatment strategies.”

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. Huang, Yuzhao, et al. “Senolytic Peptide FOXO4-DRI (Proxofim) Selectively Removes Senescent Cells From in vitro Expanded Human Chondrocytes.” Frontiers in bioengineering and biotechnology vol. 9 677576. 29 Apr. 2021, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8116695/
  2. Sun, Yan et al. “FOXO4 Inhibits the Migration and Metastasis of Colorectal Cancer by Regulating the APC2/β-Catenin Axis.” Frontiers in cell and developmental biology vol. 9 659731. 23 Sep. 2021. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8495124/
  3. Krimpenfort P, Berns A. Rejuvenation by Therapeutic Elimination of Senescent Cells. Cell. 2017 Mar 23;169(1):3-5. https://pubmed.ncbi.nlm.nih.gov/28340347/
  4. Marjolein P. Baar et al, Targeted Apoptosis of Senescent Cells Restores Tissue Homeostasis in Response to Chemotoxicity and Aging. Vol 169 Issue 1, https://doi.org/10.1016/j.cell.2017.02.031
  5. Anne-Laure Bulteau, Luke I. Szweda, Bertrand Friguet, Age-Dependent Declines in Proteasome Activity in the Heart, Archives of Biochemistry and Biophysics, Volume 397, Issue 2, 2002, Pages 298-304, ISSN 0003-9861, https://doi.org/10.1006/abbi.2001.2663
  6. Murtaza G, Khan AK, Rashid R, Muneer S, Hasan SMF, Chen J. FOXO Transcriptional Factors and Long-Term Living. Oxid Med Cell Longev. 2017;2017:3494289. doi: 10.1155/2017/3494289. Epub 2017 Aug 15. https://pubmed.ncbi.nlm.nih.gov/28894507
  7. Lee, S., & Dong, H. H. (2017). FoxO integration of insulin signaling with glucose and lipid metabolism. The Journal of Endocrinology, 233(2), R67–R79.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5480241/
  8. Zhang, C., Xie, Y., Chen, H., Lv, L., Yao, J., Zhang, M., Xia, K., Feng, X., Li, Y., Liang, X., Sun, X., Deng, C., & Liu, G. (2020). FOXO4-DRI alleviates age-related testosterone secretion insufficiency by targeting senescent Leydig cells in aged mice. Aging, 12(2), 1272–1284. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7053614/
  9. Ciechanover A, Brundin P. The ubiquitin-proteasome system in neurodegenerative diseases: sometimes the chicken, sometimes the egg. Neuron. 2003 Oct 9;40(2):427-46. https://pubmed.ncbi.nlm.nih.gov/14556719
  10. Wei Hu, Zhi Yang, Wenwen Yang, Mengzhen Han, Baoping Xu, Zihao Yu, Mingzhi Shen, Yang Yang, Roles of forkhead box O (FoxO) transcription factors in neurodegenerative diseases: A panoramic view, Progress in Neurobiology, Volume 181, 2019, 101645, ISSN 0301-0082, https://doi.org/10.1016/j.pneurobio.2019.101645
Bremelanotide Peptide and HSDD Related-Research

Bremelanotide Peptide and HSDD Related-Research

Bremelanotide, also known as PT-141, is a synthetic cyclic heptapeptide derived from Melanotan II (MT-II), a synthetic analog of the melanocortin hormone α-melanocyte-stimulating hormone (α-MSH).[1][2] It was initially investigated for its potential role in addressing hypoactive sexual desire disorder (HSDD) in female research models, as evaluated in Phase IIb clinical trials by qualified researchers. Research has also explored its potential applications in managing acute hemorrhage, suggesting broader physiological interactions beyond its primary area of study.
 

Mechanism of Action

The biological activity of Bremelanotide is hypothesized to be mediated through its selective agonism of melanocortin receptors, particularly MC3R and MC4R.[3] MC3R is predominantly expressed in the hypothalamus and has been linked to energy homeostasis, metabolic regulation, and neuroendocrine modulation. Research suggests that MC3R activity may impact feeding behavior, glucose metabolism, and lipid balance, though the precise regulatory mechanisms remain under investigation.

Conversely, MC4R is believed to play a critical role in suppressing hunger hormone signaling and regulating energy expenditure. Preclinical data suggest that its activation within the CNS may contribute to neurogenic control of metabolic functions, potentially impacting the regulation of adipose stores. In addition, MC4R has been proposed to have a role in reproductive signaling. Receptor activation is often hypothesized to impact neuroendocrine pathways linked to reproductive physiology.

Preliminary studies suggest that Bremelanotide’s binding to MC3R and MC4R may lead to neuronal activation in the hypothalamus. This may potentially trigger downstream signaling cascades associated with autonomic and neuroendocrine responses. Laboratory studies of murine research models suggest that this interaction may contribute to behavioral responses related to copulatory arousal. However, further research is necessary to elucidate the exact mechanisms underlying these findings.

 

Scientific Research and Studies

 

Early Investigations of Bremelanotide Peptide

An early 2000s study[4] investigated the potential neuropharmacological impacts of Bremelanotide in murine models, focusing on its possible role in modulating mating behavior. The study involved observing female murine models to study behavioral responses following peptide exposure.

Observations suggested that while research models exhibited increased solicitation related to mating behavior, there were no notable alterations in motor activity, lumbar lordosis, or other mating-related behaviors. Based on these findings, researchers hypothesized that Bremelanotide does not act as a general motor stimulant but may potentially exert selective pharmacological impacts on the central nervous system (CNS), particularly through melanocortin receptor activation. The study further suggested that central melanocortin pathways might be integral to neurochemical mechanisms underlying copulation-related arousal.

Researchers further noted the stability and selectivity of this response across varied experimental conditions, citing, “The ability of PT-141 to enhance solicitation in two distinctive testing environments indicates that the effect [appears] selective and stable, and suggests that central melanocortin systems are part of the neurochemical network that evokes appetitive sexual behavior in female rats.” These findings provided preliminary data that suggests the role of melanocortin receptors in modulating copulatory motivation may warrant further investigation into the underlying neuroendocrine mechanisms.

 

Neurophysiological Interactions of Bremelanotide in the Central Nervous System

Studies on the Bremelanotide peptide have focused on its potential interactions within the central nervous system (CNS), particularly in brain regions implicated in neuroendocrine and behavioral responses. Preclinical studies utilizing murine models with elevated levels of reproductive hormones have reportedly displayed behavioral modifications following peptide introduction. According to reports, these studies have primarily assessed appetitive behaviors, such as increased locomotion and solicitation, alongside consummatory responses, including lordosis.

Experimental findings suggest that Bremelanotide exposure may be associated with heightened hunger-related behaviors without significantly altering consummatory responses. These studies report that the peptide’s impacts were observed following both peripheral and direct introduction into the lateral ventricles or the medial preoptic area (mPOA) but not the ventromedial hypothalamus. The mPOA has been implicated in modulating the drive toward mating behaviors across various species, though its precise role remains under investigation. Bremelanotide’s interaction with this region, as well as other hypothalamic and limbic structures, suggests potential involvement in neural pathways associated with behavioral modulation. It has been hypothesized that Bremelanotide may exert its impacts through the activation of dopamine terminals within the mPOA, though further research is required to validate this hypothesis.[5]

To further elucidate these mechanisms, a randomized, double-blinded, placebo-controlled crossover study[6] incorporated psychometric assessments, functional neuroimaging, and hormonal analyses to examine the impact of MC4R agonism on neural processing. Results suggested that MC4R agonists, including Bremelanotide, might support an increase in copulatory motivation for up to 24 hours relative to placebo controls. Functional neuroimaging analyses suggested increased activation in the cerebellar and supplementary motor regions, alongside possible deactivation of the secondary somatosensory cortex when exposed to erotic stimuli. Additionally, MC4R agonism was associated with heightened functional connectivity between the amygdala and insular cortex under similar conditions. These findings suggest a potential role of melanocortin receptor modulation in neural circuits governing behavioral and neuroendocrine responses. Further studies are warranted to delineate the precise neurophysiological mechanisms underlying these observations.

 

Melanocortin Receptor Activation and Cavernosal Response

Bremelanotide has been hypothesized to activate melanocortin 4 receptors (MC4R) and modulate vasodilatory pathways, potentially influencing erectile function in male animal models.

Research[7] suggests that this activation may upregulate the production of nitric oxide (NO) within penile tissues, which may ultimately contribute to increased cavernosal pressure. Bremelanotide, a synthetic derivative of Melanotan-II (MT-II), shares a similar receptor affinity profile, with both peptides exhibiting agonistic properties toward melanocortin receptors.

Experimental findings suggest that melanocortin agonists might induce dose-dependent elevations in cavernosal pressure. The non-selective MC3R and MC4R antagonist SHU 9119 did not appear to directly impact systemic or cavernosal blood pressure; however, it seemingly inhibited the cavernosal pressure increases induced by melanocortin agonists. Additionally, SHU 9119 was reported to suppress the depressor response potentially associated with melanocortin activation.

Further studies investigated the role of the NO-cyclic GMP-dependent pathway in melanocortin-mediated cavernosal responses. When a pharmacological combination of phentolamine mesylate, papaverine, and prostaglandin E1 (PGE1) was locally introduced to cavernosal tissue, cavernosal pressure reportedly increased fourfold. The involvement of neuronal NO release was examined through bilateral pudendal nerve transection and inhibition of NO synthase via L-NAME. These interventions appeared to negate the cavernosal pressure increases observed with melanocortin agonists, suggesting that central melanocortin receptor activation might influence penile tissue responses through NO-mediated neural pathways.

These findings provide preliminary insights into the potential physiological interactions between melanocortin receptor activation and neurovascular regulation, though further research is necessary to elucidate the precise mechanisms involved.

 

Bremelanotide Peptide and Hemorrhagic Shock

In 2009, a modified form of Bremelanotide was explored for its potential role in mitigating hemorrhagic shock. As an agonist of both melanocortin 1 receptor (MC1R) and melanocortin 4 receptor (MC4R), the peptide has been hypothesized to exert protective impacts against ischemic injury by supporting tissue resilience under conditions of reduced blood perfusion.

Preclinical investigations suggest that its receptor interactions may contribute to vascular stability and modulate systemic responses to hypovolemia. To further assess its viability in this context, a structurally altered analog, PL-6983, was developed and advanced to Phase IIb clinical trials.

 

Bremelanotide Peptide and Infectious Disease

Research on melanocortin receptors (MC1R) suggests that they may modulate immune responses, particularly in fungal infections. In experimental murine models, MC1R activation has been associated with antifungal and anti-inflammatory properties[9], suggesting a possible role in host defense mechanisms. Given the limitations of conventional antifungal research tools, many of which exhibit restrictive mechanisms of action and significant adverse impacts, MC1R-targeting compounds may offer an alternative strategy for infection management. This might prove particularly relevant for immunocompromised individuals, where fungal infections pose substantial morbidity and mortality risks.

 

Bremelanotide Peptide and Oncological Research

MC1R has been implicated in DNA repair mechanisms, suggesting its potential relevance in oncological studies. Genetic variants of MC1R have been linked to increased susceptibility to basal cell carcinoma and squamous cell carcinoma, suggesting a role in cutaneous oncogenesis. Investigations into melanocortin receptor modulation propose that alterations in Bremelanotide or its derivatives may influence cellular repair pathways, potentially contributing to strategies aimed at mitigating cancer risk or progression[10]. However, further research is required to determine the mechanistic implications of MC1R modulation in cancer mitigation.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. Pfaus, J., Giuliano, F., & Gelez, H. (2007). Bremelanotide: an overview of preclinical CNS effects on female sexual function. The journal of sexual medicine, 4 Suppl 4, 269–279. https://doi.org/10.1111/j.1743-6109.2007.00610.x
  2. National Center for Biotechnology Information (2023). PubChem Compound Summary for CID 9941379, Bremelanotide. Retrieved August 10, 2023 from Pubchem.
  3. Renquist, B. J., Lippert, R. N., Sebag, J. A., Ellacott, K. L., & Cone, R. D. (2011). Physiological roles of the melanocortin MC₃ receptor. European journal of pharmacology, 660(1), 13–20. https://doi.org/10.1016/j.ejphar.2010.12.025
  4. Renquist, B. J., Lippert, R. N., Sebag, J. A., Ellacott, K. L., & Cone, R. D. (2011). Physiological roles of the melanocortin MC₃ receptor. European journal of pharmacology, 660(1), 13–20. https://doi.org/10.1016/j.ejphar.2010.12.025
  5. Vemulapalli, R., Kurowski, S., Salisbury, B., Parker, E., & Davis, H. (2001). Activation of central melanocortin receptors by MT-II increases cavernosal pressure in rabbits by the neuronal release of NO. British journal of pharmacology, 134(8), 1705–1710. https://doi.org/10.1038/sj.bjp.0704437
  6. Thurston, L., Hunjan, T., Mills, E. G., Wall, M. B., Ertl, N., Phylactou, M., Muzi, B., Patel, B., Alexander, E. C., Suladze, S., Modi, M., Eng, P. C., Bassett, P. A., Abbara, A., Goldmeier, D., Comninos, A. N., & Dhillo, W. S. (2022). Melanocortin 4 receptor agonism enhances sexual brain processing in women with hypoactive sexual desire disorder. The Journal of Clinical Investigation, 132(19), e152341. https://doi.org/10.1172/JCI152341
  7. Adan, R. A., Tiesjema, B., Hillebrand, J. J., la Fleur, S. E., Kas, M. J., & de Krom, M. (2006). The MC4 receptor and control of appetite. British journal of pharmacology, 149(7), 815–827. https://doi.org/10.1038/sj.bjp.0706929
  8. Pfaus, J. G., Shadiack, A., Van Soest, T., Tse, M., & Molinoff, P. (2004). Selective facilitation of sexual solicitation in the female rat by a melanocortin receptor agonist. Proceedings of the National Academy of Sciences of the United States of America, 101(27), 10201–10204. https://doi.org/10.1073/pnas.0400491101
  9. H. Ji et al., “The Synthetic Melanocortin (CKPV)2 Exerts Anti-Fungal and Anti-Inflammatory Effects against Candida albicans Vaginitis via Inducing Macrophage M2 Polarization,” PLoS ONE, vol. 8, no. 2, Feb. 2013 https://doi.org/10.1371/journal.pone.0056004
  10. Maresca V, Flori E, Picardo M. Skin phototype: a new perspective. Pigment Cell Melanoma Res. 2015 Jul;28(4):378-89. doi: 10.1111/pcmr.12365. Epub 2015 Apr 11. PMID: 25786343. https://pubmed.ncbi.nlm.nih.gov/25786343/
Pralmorelin Peptide and Growth Hormone Secretegogue Receptors (GHS-Rs)

Pralmorelin Peptide and Growth Hormone Secretegogue Receptors (GHS-Rs)

Pralmorelin, also referred to as Growth Hormone Releasing Peptide-2 (GHRP-2), is a synthetic pentapeptide classified as a growth hormone secretagogue. Structurally analogous to met-enkephalin[1], it appears to lack opioid activity and instead interacts with the ghrelin/growth hormone secretagogue receptors (GHS-Rs) to stimulate growth hormone (GH) release. Initially developed as a diagnostic agent for assessing GH deficiency within laboratory settings, Pralmorelin has since become a subject of extensive research due to its potential roles in hunger hormone signal regulation, metabolic modulation, and neuroendocrine signaling.

Studies suggest that Pralmorelin primarily exerts its impacts through its interaction with GHS-Rs, which are widely expressed in the hypothalamus and pituitary gland. Upon binding, it is believed to induce a conformational change in the receptor, activating intracellular signaling cascades mediated by G-proteins. This process may initiate the phospholipase C (PLC) pathway, leading to the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) into inositol triphosphate (IP3) and diacylglycerol (DAG). The proposed subsequent release of calcium ions and activation of protein kinase C (PKC) may facilitate GH secretion from somatotroph cells in the anterior pituitary.[2, 3]

Additionally, Pralmorelin appears to stimulate the cyclic adenosine monophosphate (cAMP) pathway, further amplifying GH synthesis and release. In bovine studies, interactions with calcium channels and growth hormone release factor receptors have also been suggested as contributing factors. Apart from GH regulation, Pralmorelin is speculated to influence neuropeptide signaling, particularly by supporting the expression of hunger hormone-stimulating peptides like neuropeptide Y (NPY) and agouti-related peptide (AgRP) while concurrently suppressing melanocyte-stimulating hormone (α-MSH). These mechanisms collectively implicate Pralmorelin in metabolic and neuroendocrine functions beyond GH secretion.

 

Scientific Research and Studies

 

Pralmorelin Peptide and Growth Hormone Deficiency Diagnosis

The insulin tolerance test (ITT) is employed to assess growth hormone (GH) deficiency; however, this method is associated with potentially severe adverse impacts and ancillary impacts. To address these limitations, a clinical study was carried out to determine the possible diagnostic potential of Pralmorelin as an alternative method for evaluating GH deficiency.

As per the study reports[4], a cohort of 135 research models initially underwent ITT, identifying 77 research models with normal GH responses and 58 with peak GH levels below 3 ng/mL. Following an overnight fasting period, the cohort was introduced to Pralmorelin, with blood samples collected at regular intervals. Researchers state that a distinct peak in GH levels was observed one-hour post peptide introduction in all subjects, with no significant differences based on sex.

That said, a marginal reduction in GH response was noted in research models with higher body mass index (BMI) and advanced cellular age. These findings were reproducible upon repeated evaluation, suggesting consistently elevated GH levels in functional research models compared to those with confirmed GH deficiency. The study findings suggest that Pralmorelin may serve as a reliable diagnostic tool for severe GH deficiency. Its efficacy varies slightly with adiposity and cellular age.

In a separate study[5], the diagnostic performance of Pralmorelin was compared to conventional stimulatory agents such as arginine and L-dopa in GH deficiency (GHD). Twenty-four research models of GHD and previously introduced to at least one conventional agent were enrolled in the study, which evaluated the introduction of Growth Hormone-Releasing Hormone (GHRH) and GHRP-2. The introduction of Pralmorelin markedly elevated serum GH levels. Among the 21 research models that exhibited a strong GH response, GHRH and GHRP-2 were simultaneously introduced. Subsequently, 15 of these research models underwent intranasal introduction of GHRP-2, which similarly induced a significant GH response.

All research models exposed to Pralmorelin in this study indicated good tolerance, suggesting a favorable profile in younger research models. Notably, reports suggest that Pralmorelin appears to exhibit a distinct advantage as a predictor of pituitary GH secretory capacity, a characteristic not observed with conventional diagnostic agents. These findings highlight the potential of Pralmorelin as an impactful and noninvasive diagnostic tool for researching GH deficiency.

 

Combined Studies with TRH and GnRH

A clinical investigation[6] studied the impacts of Pralmorelin, Thyrotropin-Releasing Hormone (TRH), and Gonadotropin-Releasing Hormone (GnRH), both individually and in combination, in subjects with prolonged hyposomatotropism, hypogonadism, or hypothyroid complications. The study recruited 33 male research models to assess their endocrine responses to different hormonal stimulation regimens. Over five days, subjects were assigned to one of four groups: placebo, the hourly introduction of Pralmorelin, the combined introduction of Pralmorelin and TRH every hour, or a combination of Pralmorelin, TRH, and GnRH every 90 minutes.

Serum samples were collected on both the first and last nights of the study for endocrine analysis. Results suggest that the combination of GHRP-2, GnRH, and TRH elicited the most pronounced activation of the growth hormone, thyroid-stimulating hormone, and luteinizing hormone axes, potentially influencing metabolic pathways. In contrast, Pralmorelin alone produced minimal endocrine impacts, and, according to the reports, the combination of Pralmorelin and TRH induced only partial hormonal activation compared to the triple-hormone regimen. These findings suggest a potential synergistic interaction between Pralmorelin, GnRH, and TRH in supporting hormonal responses, suggesting their possible role in managing endocrine deficiencies and related metabolic disturbances.

 

Pralmorelin Peptide and Hunger Hormone Signal Modulation

This controlled experiment studies the potential role of Growth Hormone-Releasing Peptide-2 (GHRP-2) in hunger hormone signal regulation. Seven functional male research models were allocated into two groups, with one group receiving a continuous subcutaneous infusion of GHRP-2 and the other receiving a saline placebo over 4.5 hours. Following the infusion, all research models were provided unlimited access to nourishment, and caloric intake was measured to assess differences between the groups.

Results suggested a significant increase in caloric intake among research models exposed to Pralmorelin, with an average intake approximately 36% higher than that of the control group. This reported increase in hunger hormone signals was accompanied by a concurrent elevation in circulating growth hormone (GH) levels, based on which the researchers concluded that “GHRP-2, like ghrelin, increases food intake, suggesting that GHRP-2 [may be] a valuable tool for investigating ghrelin effects on eating behavior.”

These findings support the hypothesis that Pralmorelin may impact hunger hormone stimulation, potentially through its interaction with ghrelin receptors and downstream neuroendocrine signaling pathways.

 

General Pharmacological Impacts

Preclinical investigations[8] have studied the pharmacological profile of Pralomorelin in animal models. Studies conducted in rabbits and guinea pigs suggest that Pralmorelin does not significantly impact central nervous system function. However, a mild increase in motility was observed in the isolated rabbit ileum, and concentration-dependent support of contraction was noted in the isolated guinea pig ileum.

Beyond these gastrointestinal impacts, no substantial alterations were reported in respiratory, digestive, renal, or circulatory system functions. Researchers concluded that the peptide “has no serious general pharmacological effects at [concentration] levels showing GH-releasing activity in the experimental animals,” and the peptide is speculated to support the diagnosis of “serious GH deficiency and short stature.”[8]

 

Pralmorelin Peptide and Antioxidative Properties

Studies suggest that Pralmorelin may exert antioxidative impacts, with data suggesting its interaction with CD36, a receptor involved in the uptake of oxidized low-density lipoprotein (OxLDL). This interaction might potentially limit the cellular absorption of OxLDL, a well-regarded contributor to atherogenesis. In murine models deficient in the ApoE gene (ApoE⁻/⁻), prolonged Pralmorelin exposure over 12 weeks was observed to increase circulating insulin-like growth factor-I (IGF-I) levels by approximately 1.2 to 1.6 times baseline values. Additionally, a 66% reduction in circulating interferon-gamma levels was reported.

While Pralmorelin did not appear to significantly alter the extent of atherosclerotic plaque formation, it appeared to reduce superoxide production within the aorta, as supported by data collected concerning dihydroethidium staining. Furthermore, Pralmorelin exposure resulted in a 92% reduction in aortic gene expression of 12/15-lipoxygenase, as well as a downregulation of interferon-gamma and macrophage migration inhibitory factor. Observations in cultured aortic smooth muscle cells suggest that Pralmorelin may counteract peroxide production induced by OxLDL, mitigate IGF-I receptor suppression, and potentially inhibit apoptosis. In macrophages exposed to OxLDL, the peptide is hypothesized to reduce lipid accumulation, further supporting its antioxidative and protective potential against proatherogenic agents.[9]

 

Pralmorelin Peptide and Muscular Tissue Preservation

Murine models of thermal injury suggest that Pralmorelin may play a role in mitigating muscular tissue catabolism by reducing proinflammatory markers such as interleukin-6 (IL-6) and E3 ubiquitin ligases (MuRF-1 and MAFbx), both of which are implicated in muscular tissue degradation under critical conditions. Additionally, researchers propose that Pralmorelin may directly attenuate total muscle protein breakdown, indicating a potential muscle-sparing impact. Case studies further suggest that the peptide may contribute to muscular tissue hypertrophy and mass gain.[11]

 

Pralmorelin Peptide and Inflammation

To further investigate Pralmorelin’s impacts on oxidative stress and inflammation, murine models of acute lung injury were studied following peptide introduction. Findings suggest that Pralmorelin exposure may reduce pulmonary edema, neutrophil infiltration, and proinflammatory cytokine levels. Additionally, the peptide appears to suppress nuclear factor-kappa B (NF-κB) activation, a key regulator of inflammatory cascades often associated with tissue damage. These findings[12] suggest that Pralmorelin may exert protective impacts against inflammation-induced tissue injury.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. Garcia JM, Merriam GR, Kargi AY. Growth Hormone in Aging. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext. South Dartmouth (MA): MDText.com https://www.ncbi.nlm.nih.gov/books/NBK279163/
  2. Yin, Y., Li, Y., & Zhang, W. (2014). The growth hormone secretagogue receptor: its intracellular signaling and regulation. International journal of molecular sciences, 15(3), 4837–4855. https://doi.org/10.3390/ijms15034837
  3. Sinha, D. K., Balasubramanian, A., Tatem, A. J., Rivera-Mirabal, J., Yu, J., Kovac, J., Pastuszak, A. W., & Lipshultz, L. I. (2020). Beyond the androgen receptor: the role of growth hormone secretagogues in the modern management of body composition in hypogonadal males. Translational andrology and urology, 9(Suppl 2), S149–S159. https://doi.org/10.21037/tau.2019.11.30
  4. Roh SG, He ML, Matsunaga N, Hidaka S, Hidari H. Mechanisms of action of growth hormone-releasing peptide-2 in bovine pituitary cells. J Anim Sci. 1997 Oct;75(10):2744-8. doi: 10.2527/1997.75102744x. PMID: 9331879. https://pubmed.ncbi.nlm.nih.gov/9331879/
  5. Asad Rahim, Stephen M. Shalet, in Growth Hormone Secretagogues, 1999. Does desensitization to growth hormone secretagogues occur? https://www.sciencedirect.com/
  6. Van den Berghe G, Baxter RC, Weekers F, Wouters P, Bowers CY, Iranmanesh A, Veldhuis JD, Bouillon R. The combined administration of GH-releasing peptide-2 (GHRP-2), TRH and GnRH to men with prolonged critical illness evokes superior endocrine and metabolic effects compared to treatment with GHRP-2 alone. Clin Endocrinol (Oxf). 2002 May;56(5):655-69. doi: 10.1046/j.1365-2265.2002.01255.x. PMID: 12030918. https://pubmed.ncbi.nlm.nih.gov/12030918/
  7. Laferrère, Blandine et al. Growth hormone-releasing peptide-2 (GHRP-2), like ghrelin, increases food intake in healthy men. The Journal of Clinical Endocrinology and Metabolism vol. 90,2 (2005): 611-4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2824650/
  8. Furuta S, Shimada O, Doi N, Ukai K, Nakagawa T, Watanabe J, Imaizumi M. General pharmacology of KP-102 (GHRP-2), a potent growth hormone-releasing peptide. Arzneimittelforschung. 2004;54(12):868-80. doi: 10.1055/s-0031-1297042. PMID: 15646371. https://pubmed.ncbi.nlm.nih.gov/15646371/
  9. Titterington JS, Sukhanov S, Higashi Y, Vaughn C, Bowers C, Delafontaine P. Growth hormone-releasing peptide-2 suppresses vascular oxidative stress in ApoE-/- mice but does not reduce atherosclerosis. Endocrinology. 2009 Dec;150(12):5478-87. doi: 10.1210/en.2009-0283. Epub 2009 Oct 9. PMID: 19819949; PMCID: PMC2795722. https://pmc.ncbi.nlm.nih.gov/articles/PMC2795722/
  10. Sheriff, S., Joshi, R., Friend, L. A., James, J. H., & Balasubramaniam, A. (2009). Ghrelin receptor agonist, GHRP-2, attenuates burn injury-induced MuRF-1 and MAFbx expression and muscle proteolysis in rats. Peptides, 30(10), 1909–1913. https://doi.org/10.1016/j.peptides.2009.06.029
  11. Sigalos, J. T., & Pastuszak, A. W. (2018). The Safety and Efficacy of Growth Hormone Secretagogues. Sexual medicine reviews, 6(1), 45–53. https://doi.org/10.1016/j.sxmr.2017.02.004
  12. Li, G., Li, J., Zhou, Q., Song, X., Liang, H., & Huang, L. (2010). Growth hormone-releasing peptide-2, a ghrelin agonist, attenuates lipopolysaccharide-induced acute lung injury in rats. The Tohoku journal of experimental medicine, 222(1), 7–13. https://doi.org/10.1620/tjem.222.7
Insights into the Tesamorelin, Ipamorelin, and CJC-1295 Peptide Blend

Insights into the Tesamorelin, Ipamorelin, and CJC-1295 Peptide Blend

The Tesamorelin & CJC-1295 (Mod GRF 1-29) & Ipamorelin peptide blend represents a combination of synthetic peptides, each with distinct properties that researchers have hypothesized may hold mechanisms for stimulating growth hormone (GH) synthesis and secretion. Although structurally and functionally unique, these peptides appear to share a common focus on modulating the endocrine system’s GH regulatory axis. This blend has been the subject of various research efforts to explore its biochemical properties, interactions with receptors, and physiological effects.
 

Tesamorelin Peptide

Tesamorelin is a synthetic analog of growth hormone-releasing hormone (GHRH), engineered to resemble the natural peptide that scientists consider to be responsible for stimulating GH secretion. Structurally, Tesamorelin consists of 44 amino acids and incorporates specific modifications to enhance its stability against enzymatic degradation. One notable modification is the introduction of a trans-3-hexenoic acid group at its C-terminus, often referred to as an omega-amino acid modification.[1] This alteration is hypothesized to improve resistance to enzymatic breakdown, prolonging its functional lifespan in biological systems. Additionally, the N-terminal acetylation (CH₃CO-) has been suggested to further contribute to its structural resilience and bioactivity. These modifications result in the designation N-(trans-3-hexenoyl)-[Tyr1]hGRF(1–44)NH2 acetate.

Tesamorelin’s mechanism of action is thought to involve binding to GHRH receptors located in the hypothalamus and pituitary gland,[1] thereby triggering the release of endogenous GH. This proposed mechanism has garnered interest in exploring its implications for protein metabolism, lipid oxidation, and cellular growth processes.

 

CJC-1295 (Mod GRF 1-29) Peptide

CJC-1295 (Mod GRF 1-29) is a synthetic derivative of the functional segment of GHRH, comprising 29 amino acids. This peptide is often described as a tetrasubstituted variant designed to resist enzymatic degradation and extend its half-life. Unlike its predecessor with a Drug Affinity Complex (DAC), the Mod GRF 1-29 variant lacks the DAC but appears to have retained significant stability and activity. Research suggests that CJC-1295 interacts with GHRH receptors in the pituitary gland, where it may stimulate GH secretion.

Its proposed mechanism mimics that of GHRH, potentially enhancing protein synthesis, promoting muscle hypertrophy, and influencing metabolic pathways.[2] The peptide’s engineered design aims to maintain functionality while reducing susceptibility to degradation, making it a key component of this peptide blend.

 

Ipamorelin Peptide

Ipamorelin is a synthetic pentapeptide and a selective agonist for the ghrelin receptor, also known as the growth hormone secretagogue (GHS) receptor. This receptor is predominantly expressed in the pituitary gland, where its activation may stimulate the release of GH. Ipamorelin exhibits high specificity for the GHS receptor, with minimal interaction with other hormonal systems, reducing the likelihood of off-target action.

Research suggests that Ipamorelin’s apparent selective binding to the GHS receptor might enhance GH secretion without altering levels of other hormones, such as cortisol or prolactin.[3] This unique mechanism positions Ipamorelin as a potential tool for investigating GH-related physiological processes, including growth, repair, and metabolic regulation.

This tri-peptide blend appears to combine Tesamorelin’s GHRH receptor affinity, CJC-1295’s enhanced stability and activity, and Ipamorelin’s selective ghrelin receptor stimulation. Together, these peptides may offer synergistic effects on GH secretion, which warrants further investigation through controlled research studies.

 

Scientific Research and Studies

 

Tesamorelin, CJC-1295 (Mod GRF 1-29), and Ipamorelin Blend and the Pituitary Gland

The peptide blend comprising Tesamorelin, CJC-1295 (Mod GRF 1-29), and Ipamorelin is speculated to potentially interact with the pituitary gland, primarily through receptor-specific binding that may modulate the secretion of growth hormone (GH).

Tesamorelin and CJC-1295 (Mod GRF 1-29) are analogs of growth hormone-releasing hormone (GHRH) that appear to target GHRH receptors on somatotrophs in the anterior pituitary. Research suggests that their interaction may induce receptor conformational changes, activating downstream intracellular signaling cascades.[4] Specifically, these peptides are hypothesized to stimulate adenylate cyclase, leading to the conversion of adenosine triphosphate (ATP) into cyclic adenosine monophosphate (cAMP). The resulting elevation of cAMP levels is thought to activate protein kinase A (PKA), which phosphorylates various intracellular targets. This signaling cascade is believed to culminate in the synthesis and secretion of human growth hormone (hGH). The hGH released from somatotroph cells may also facilitate the production of insulin-like growth factor-1 (IGF-1), deemed a critical mediator of growth hormone activity.

CJC-1295 (Mod GRF 1-29) exhibits notable structural modifications, including four amino acid substitutions, which may enhance its resistance to enzymatic degradation. This increased stability is reported to extend its half-life, improving its pharmacokinetic profile. Additionally, these modifications allow a proportion of the peptide to covalently bind to serum albumin, thereby prolonging its duration of action. Trace binding to fibrinogen and immunoglobulin G (IgG) has also been observed. These properties collectively suggest a sustained mechanism of action, with a potential for increased biological activity.[5]

Ipamorelin, in contrast, is a selective agonist for the ghrelin receptor, also referred to as the growth hormone secretagogue receptor (GHSR). This peptide is believed to bind to GHSR on somatotroph cells, initiating signaling pathways that may promote GH secretion. Unlike some other secretagogues, Ipamorelin appears to exert a high degree of specificity for GHSR, with apparently minimal off-target effects on other endocrine pathways, including prolactin and adrenocorticotropic hormone (ACTH) regulation.[6]

In vitro studies[7] suggest that Ipamorelin binding to GHSR activates phospholipase C (PLC), which catalyzes the generation of inositol triphosphate (IP3) and diacylglycerol (DAG). IP3 may mobilize calcium ions (Ca2+) from intracellular stores, while DAG is thought to activate protein kinase C (PKC). These intracellular events potentially facilitate the exocytosis of vesicles containing GH from somatotroph cells. This process underscores the peptide’s role in GH secretion through precise intracellular signaling mechanisms.

The combined properties of Tesamorelin, CJC-1295 (Mod GRF 1-29), and Ipamorelin suggest a synergistic effect on pituitary function. Tesamorelin and CJC-1295 (Mod GRF 1-29) focus on GHRH receptor pathways, while Ipamorelin appears to activate the GHSR, providing complementary mechanisms to stimulate GH release. These peptides collectively indicate complex interactions with the pituitary gland, potentially enhancing GH secretion through distinct yet interconnected molecular pathways. Such findings highlight their potential implications in regulating growth hormone activity and associated metabolic processes. Further research is necessary to elucidate the full scope of their physiological effects and research applications.

 

Tesamorelin, CJC-1295 (Mod GRF 1-29), and Ipamorelin and Cardiovascular Action

The potential cardiovascular effects of Tesamorelin, Modified GRF (CJC-1295), and Ipamorelin have been studied with an emphasis on cardiac repair and lipid metabolism. Following myocardial infarction (MI), cardiac tissue often undergoes scarring, which can impair heart function, including ejection fraction and contractility. Research in animal models suggests that growth hormone secretagogues may possibly enhance post-MI cardiac repair. Observed outcomes include reduced infarct size, improved cardiac ejection fraction, and restoration of overall cardiac function.[8]

Ipamorelin’s activation of the GHS-R1a receptor is hypothesized to exert a possible cardioprotective effect through positive inotropic properties. Researchers elucidate that, “Through activation of GHS-R1a, secretagogues produced a positive inotropic effect on ischemic cardiomyocytes and protected them from I/R injury, likely by safeguarding or restoring p-PLB (and hence SR Ca2+ content) to facilitate the maintenance or recovery of normal cardiac contractility.”

Additionally, Tesamorelin, while primarily recognized for its lipodystrophy-reducing properties, has exhibited potential cardiovascular action, particularly in HIV-positive models. Some studies highlight its potential to lower triglycerides, total cholesterol, and non-HDL cholesterol levels,[9] suggesting a broader impact on lipid metabolism and cardiovascular function. These findings collectively underscore the potential of this peptide blend to modulate cardiac function and lipid profiles.

 

Tesamorelin, CJC-1295 (Mod GRF 1-29), and Ipamorelin and Effect on Gastrointestinal Tract

The peptide blend comprising Tesamorelin, Modified GRF (CJC-1295), and Ipamorelin may hold varying degrees of influence on the gastrointestinal (GI) tract through distinct mechanisms. Tesamorelin appears to enhance gastric emptying and gastrointestinal motility, as observed in preclinical studies. This action suggests its potential utility in addressing motility disorders or delayed gastric emptying.

Modified GRF, while exhibiting minimal direct effects on motility, appears to support GI function by improving gut barrier integrity and mitigating intestinal inflammation. This effect has been primarily studied in animal models of colitis, where the peptide appeared to host anti-inflammatory properties and potential contributions to the restoration of gut homeostasis.

Ipamorelin, as a selective agonist of the ghrelin receptor, is posited to exert effects through receptor activation within the GI tract. Upon binding to ghrelin receptors, Ipamorelin may stimulate gut motility, improve nutrient absorption, and contribute to tissue repair following gastrointestinal injury. Furthermore, preclinical research indicates its potential to mitigate inflammation and promote recovery in various models of GI injury. According to the studies, Ipamorelin may “increase total body fat percentages,” suggesting the peptide is a “potent and selective stimulator of GH that [may] significantly influence the GI system, body composition, and adiposity.”[10]

 

Synergistic Potential of Tesamorelin, CJC-1295 (Mod GRF 1-29), and Ipamorelin Peptides

The combination of Tesamorelin, Modified GRF (CJC-1295), and Ipamorelin has been proposed by its researchers to enhance growth hormone (GH) secretion through distinct yet complementary mechanisms of action. Studies suggest that Tesamorelin and Modified GRF, when combined, may produce a synergistic increase in GH levels, surpassing the effects of either peptide alone.[11] This blend is also speculated to cause reductions in visceral adipose tissue, particularly in models of HIV-associated lipodystrophy, though this effect may have been reversed upon study cessation.

Beyond GH secretion, this peptide combination, as per the research, is suggested to support improved sleep-wake cycles, increased behavioral mood, energy, and sustained GH production over time. Together, these peptides may also synergistically enhance insulin-like growth factor 1 (IGF-1) levels, potentially leading to improved muscle growth, bone density, cognitive function, and cellular repair, making this blend a promising tool for studies exploring diverse metabolic and physiological challenges.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. National Center for Biotechnology Information (2023). PubChem Compound Summary for CID 9831659, Ipamorelin. https://pubchem.ncbi.nlm.nih.gov/compound/Ipamorelin.
  2. National Center for Biotechnology Information (2023). PubChem Compound Summary for CID 56841945. https://pubchem.ncbi.nlm.nih.gov/compound/56841945.
  3. National Center for Biotechnology Information (2023). PubChem Compound Summary for CID 16137828, Tesamorelin. https://pubchem.ncbi.nlm.nih.gov/compound/Tesamorelin
  4. Spooner, L. M., & Olin, J. L. (2012). Tesamorelin: a growth hormone-releasing factor analogue for HIV-associated lipodystrophy. The Annals of pharmacotherapy, 46(2), 240–247. https://doi.org/10.1345/aph.1Q629
  5. Zhou, F., Zhang, H., Cong, Z., Zhao, L. H., Zhou, Q., Mao, C., Cheng, X., Shen, D. D., Cai, X., Ma, C., Wang, Y., Dai, A., Zhou, Y., Sun, W., Zhao, F., Zhao, S., Jiang, H., Jiang, Y., Yang, D., Eric Xu, H., … Wang, M. W. (2020). Structural basis for activation of the growth hormone-releasing hormone receptor. Nature communications, 11(1), 5205. https://doi.org/10.1038/s41467-020-18945-0
  6. Sinha DK, Balasubramanian A, Tatem AJ, Rivera-Mirabal J, Yu J, Kovac J, Pastuszak AW, Lipshultz LI. Beyond the androgen receptor: the role of growth hormone secretagogues in the modern management of body composition in hypogonadal males. Transl Androl Urol. 2020 Mar;9(Suppl 2):S149-S159. doi: 10.21037/tau.2019.11.30. PMID: 32257855; PMCID: PMC7108996 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7108996/
  7. Jiménez-Reina, L., Cañete, R., de la Torre, M. J., & Bernal, G. (2002). Influence of chronic treatment with the growth hormone secretagogue Ipamorelin, in young female rats: somatotroph response in vitro. Histology and histopathology, 17(3), 707–714. https://doi.org/10.14670/HH-17.707
  8. Ma Y, Zhang L, Edwards JN, Launikonis BS, Chen C. Growth hormone secretagogues protect mouse cardiomyocytes from in vitro ischemia/reperfusion injury through regulation of intracellular calcium. PLoS One. 2012;7(4):e35265. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0035265 Epub 2012 Apr 6. PMID: 22493744; PMCID: PMC3320867. https://pmc.ncbi.nlm.nih.gov/articles/PMC3320867/
  9. Stanley TL, Falutz J, Marsolais C, Morin J, Soulban G, Mamputu JC, Assaad H, Turner R, Grinspoon SK. Reduction in visceral adiposity is associated with an improved metabolic profile in HIV-infected patients receiving tesamorelin. Clin Infect Dis. 2012 Jun;54(11):1642-51. doi: 10.1093/cid/cis251. Epub 2012 Apr 10. PMID: 22495074; PMCID: PMC3348954. https://pubmed.ncbi.nlm.nih.gov/22495074/
  10. Sinha DK, Balasubramanian A, Tatem AJ, Rivera-Mirabal J, Yu J, Kovac J, Pastuszak AW, Lipshultz LI. Beyond the androgen receptor: the role of growth hormone secretagogues in the modern management of body composition in hypogonadal males. Transl Androl Urol. 2020 Mar;9(Suppl 2):S149-S159. doi: 10.21037/tau.2019.11.30. PMID: 32257855; PMCID: PMC7108996 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7108996/
  11. Bedimo R. Growth hormone and tesamorelin in the management of HIV-associated lipodystrophy. HIV AIDS (Auckl). 2011;3:69-79. doi: 10.2147/HIV.S14561. Epub 2011 Jul 10. PMID: 22096409; PMCID: PMC3218714. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3218714/
Liraglutide Peptide: Potential in Obesity and Diabetes Research

Liraglutide Peptide: Potential in Obesity and Diabetes Research

Liraglutide is a synthetic analog of the glucagon-like peptide-1 (GLP-1), an endogenous incretin hormone known for its potential role in regulating glucose metabolism and appetite.[1] Classified as a lipopeptide, Liraglutide peptide is suggested to be structurally similar to GLP-1, sharing 97% homology with its natural counterpart and containing 31 amino acids, including an arginine residue and a hexadecanoyl group. Originally developed to address the limitations of native GLP-1’s short half-life, Liraglutide peptide was reportedly engineered to achieve prolonged activity.

The development of Liraglutide peptide began with the discovery of GLP-1, an incretin hormone believed to stimulate insulin secretion and lower postprandial glucose levels. This discovery appeared to have spurred research into synthetic GLP-1 receptor agonists, culminating in the creation of Liraglutide peptide. Preclinical studies have since suggested that the peptide may be efficient in improving glycemic control, reducing weight, and thereby potentially mitigating cardiovascular risks.

The actions of Liraglutide are speculated to be mediated through its interaction with GLP-1 receptors (GLP-1R), which are widely expressed in pancreatic beta cells, the gastrointestinal tract, and the central nervous system. Upon binding to GLP-1R, Liraglutide peptide may initiate several signaling cascades that contribute to its possible diverse physiological functions.

Glucose-Dependent Insulin Secretion

Liraglutide appears to activate GLP-1R on pancreatic beta cells, possibly facilitating insulin release in response to elevated blood glucose levels.[2] This reported glucose-dependent mechanism may minimize the risk of hypoglycemia, a significant advantage over traditional insulin studies.

Glucagon Secretion

By potentially suppressing glucagon release from pancreatic alpha cells, Liraglutide is speculated to reduce hepatic glucose production, possibly contributing to improved glycemic control.[1]

Gastric Emptying

Liraglutide appears to slow gastric motility, prolonging nutrient absorption and satiety. This effect is hypothesized to play a role in appetite regulation.

Neuroendocrine Action

GLP-1R activation in the central nervous system has been linked to appetite suppression and potential enhancements in cognitive functions, as suggested by preclinical studies.[3]

Beta Cells

Research suggests that Liraglutide may stimulate the proliferation and differentiation of pancreatic beta cells, protecting them from apoptosis and promoting their long-term function.

Cardioprotective Potential

GLP-1R is also expressed in cardiac tissue, where Liraglutide may exert protective potential. Studies suggest its involvement in glucose uptake within cardiac muscles, potentially reducing ischemic damage and supporting myocardial survival.[4]

 

Scientific Research and Studies

 

Liraglutide Peptide and the Incretin Effect

The Incretin Effect, as characterized by Dr. Holst, is a physiological mechanism mediated by glucagon-like peptide-1 (GLP-1), a metabolic hormone released by the gastrointestinal (GI) tract. Incretins, including GLP-1 and glucose-dependent insulinotropic polypeptide (GIP), appear to play potential roles in lowering blood glucose levels through their perceived glucose-dependent stimulation of insulin secretion. Among these, GLP-1 is posited to exhibit superior potency compared to GIP, particularly under hyperglycemic conditions, despite circulating at significantly lower concentrations—approximately tenfold less than GIP.

A notable study[1] conducted in 2007 studied the introduction of Liraglutide peptide in isolated rat pancreases pre-exposed to sulfonylurea drugs. The findings suggested that while GLP-1 introduction under low glucose concentrations had minimal effects on insulin secretion, prior exposure to sulfonylurea compounds significantly amplified the insulinotropic response. The study reported a “dramatic stimulation of insulin secretion” under these conditions. Moreover, clinical data suggest that “30–40% of [research models exposed to] both sulfonyl urea compounds and a GLP-1 agonist (exendin 4) experience, usually mild, hypoglycemia”, underscoring the conceivably synergistic interaction between these two agents.

This study suggests the possible role of GLP-1 in the incretin effect and suggests that Liraglutide’s efficacy may be further optimized when studied alongside agents that may sensitize pancreatic beta cells, such as sulfonylureas.

 

Obesity

Research utilizing murine models has suggested that exposure to glucagon-like peptide-1 (GLP-1) and its analogs, such as GLP-1 receptor agonists (GLP-1RAs) like Liraglutide peptide, directly into the central nervous system may result in a reduction in appetite and food consumption. This observation suggests that these peptides may increase satiety signaling pathways, contributing to a sensation of fullness and a subsequent decrease in caloric intake.[5]

Recent preclinical investigations have further reported that the twice-daily exposure of GLP-1RAs in mice may produce gradual and sustained weight loss over time. This reduction in body weight may also correlate with improvements in cardiovascular risk factors and a decline in hemoglobin A1C levels, a biomarker commonly employed to evaluate long-term glycemic control and the perceived effectiveness of diabetes management resources. These findings suggest the multifaceted metabolic potential associated with Liraglutide peptide and its hypothesized capacity to influence both weight and associated physiological outcomes.

 

Liraglutide Peptide and Gastric Motility

Investigations suggest that exposure to Liraglutide peptide may result in a 23% reduction in gastric emptying within the first hour postprandially, compared to placebo. However, no significant difference was observed in the 5-hour gastric emptying time between Liraglutide peptide and the placebo. This transient postprandial delay in gastric motility may still be sufficient to enhance early satiety.[6]

The mechanisms underlying Liraglutide’s effect on gastric motility are hypothesized to be multifactorial, involving complex neural and hormonal interactions. Liraglutide peptide appears to engage GLP-1 receptors (GLP-1Rs) located both within the central nervous system (CNS) and the peripheral nervous system. Activation of GLP-1Rs on enteroendocrine cells in the gastrointestinal tract, which appear responsive to nutrient intake, likely mimics and enhances the physiological actions of endogenous GLP-1.

Upon activation, these receptors may initiate signaling through the enteric nervous system, which governs gastrointestinal motility. This signaling is thought to regulate the contractile activity of the stomach, thereby slowing the rate at which gastric contents are released into the small intestine. Concurrently, Liraglutide-mediated activation of GLP-1Rs may also engage the vagal nerve, transmitting signals to the CNS. This central pathway may further modulate autonomic feedback mechanisms that influence gastric motility, reinforcing the peptide’s potential to reduce the rate of gastric emptying. These processes collectively highlight the sophisticated interplay between peripheral and central mechanisms in mediating Liraglutide’s effects on gastric motility.[7]

 

Liraglutide Peptide and Beta Cells

Research utilizing animal models suggests that glucagon-like peptide-1 (GLP-1) and its analogs, such as Liraglutide peptide, may exert significant effects on the proliferation and growth of pancreatic beta cells. Additionally, GLP-1 analogs like Liraglutide peptide are hypothesized to facilitate the differentiation of beta cells from progenitor cells within the epithelial lining of the pancreatic duct. These peptides may also inhibit beta-cell apoptosis, thereby altering the balance between beta-cell growth and death in favor of cell survival and expansion.[8]

The cumulative data suggests that Liraglutide peptide may play a role in maintaining beta cell mass and function, which may aid in diabetes-related studies. By promoting beta cell proliferation and differentiation while concurrently reducing apoptosis, Liraglutide peptide may contribute to preserving pancreatic function and mitigating damage to beta cells caused by metabolic or inflammatory insults.

Furthermore, a pivotal study suggested that Liraglutide peptide may mitigate beta cell death triggered by elevated levels of pro-inflammatory cytokines. Experimental models of type 1 diabetes in mice have indicated that GLP-1 analogs may protect pancreatic islet cells, potentially delaying or preventing the onset of autoimmune beta cell destruction associated with type 1 diabetes. These findings underscore the potential of Liraglutide peptide as a protective agent within research related to beta cells.[8]

 

Liraglutide Peptide and Cardiovascular Impact

The distribution of glucagon-like peptide-1 (GLP-1) receptors throughout cardiac tissue suggests a potential role for GLP-1 and its analogs, such as Liraglutide peptide, in modulating cardiac function. Based on the studies, it appears that GLP-1 receptor activation may potentially increase heart rate and reduce left ventricular end-diastolic pressure, mechanisms that might mitigate left ventricular hypertrophy, cardiac remodeling, and the progression to heart failure.[9]

Emerging data suggest that GLP-1 and related peptides may reduce myocardial damage during ischemic events such as myocardial infarction. These peptides appear to facilitate glucose uptake in cardiac myocytes, thereby supplying ischemic myocardial cells with critical nutrients. This glucose uptake is noted to occur independently of insulin, highlighting a unique cardioprotective mechanism. By supporting cellular metabolism and reducing apoptosis, GLP-1 receptor agonists like Liraglutide peptide may help preserve myocardial integrity in ischemic conditions.

Studies in canine models, where GLP-1 was introduced in significant quantities, reportedly exhibited improvement in left ventricular performance and reported decrease systemic vascular resistance. These effects contribute to reductions in blood pressure and myocardial strain, potentially alleviating hypertension-related complications such as ventricular remodeling, vascular thickening, and heart failure.

Nikolaidis et al. reported “rGLP-1 dramatically improved LV and systemic hemodynamics in dogs with advanced DCM induced by rapid pacing. rGLP-1 has insulinomimetic and glucagonostatic properties, with resultant increases in myocardial glucose uptake. rGLP-1 may be a useful metabolic adjuvant in decompensated heart failure.” [10]

 

Neuroprotection

Recent findings suggest that glucagon-like peptide-1 (GLP-1) and its analogs, may hold significant neuroprotective potential. GLP-1 receptor activation has been associated with improved cognitive functions, including learning and memory, and may provide protection against neurodegenerative conditions such as Alzheimer’s disease.

Experimental studies have reported that GLP-1 appears to enhance associative and spatial learning in murine models and may possibly mitigate learning deficits in mice with specific genetic abnormalities. Notably, rats with increased expression of GLP-1 receptors in distinct brain regions exhibited superior learning and memory performance compared to control groups. This suggests a link between GLP-1 receptor activity and improved cognitive capacity.[11]

In addition to cognitive potential, GLP-1 analogs like Liraglutide peptide have been suggested by researchers to exert protective effects against excitotoxic neuronal damage. Research using rat models of neurodegeneration has revealed that Liraglutide peptide may provide fairly robust protection against glutamate-induced apoptosis, a key mechanism underlying neuronal loss in neurodegenerative disorders.[12] Furthermore, in vitro studies appear to suggest that GLP-1 analogs may promote neurite outgrowth, indicating a role in neural regeneration and repair.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. Holst JJ. The physiology of glucagon-like peptide 1. Physiol Rev. 2007 Oct;87(4):1409-39. doi: 10.1152/physrev.00034.2006. PMID: 17928588. https://pubmed.ncbi.nlm.nih.gov/17928588/
  2. Tandong Yang, Meng Chen, Jeffrey D. Carter, Craig S. Nunemaker, James C. Garmey, Sarah D. Kimble, Jerry L. Nadler, Combined treatment with lisofylline and exendin-4 reverses autoimmune diabetes, Biochemical and Biophysical Research Communications, Volume 344, Issue 3, 2006, Pages 1017-1022, ISSN 0006-291X, https://www.sciencedirect.com/science/article/pii/S0006291X06007066
  3. Blonde L, Klein EJ, Han J, Zhang B, Mac SM, Poon TH, Taylor KL, Trautmann ME, Kim DD, Kendall DM. Interim analysis of the effects of exenatide treatment on A1C, weight and cardiovascular risk factors over 82 weeks in 314 overweight patients with type 2 diabetes. https://pubmed.ncbi.nlm.nih.gov/16776751/
  4. Bose AK, Mocanu MM, Carr RD, Brand CL, Yellon DM. Glucagon-like peptide 1 can directly protect the heart against ischemia/reperfusion injury. Diabetes. 2005. https://pubmed.ncbi.nlm.nih.gov/15616022/
  5. Blonde L, Klein EJ, Han J, Zhang B, Mac SM, Poon TH, Taylor KL, Trautmann ME, Kim DD, Kendall DM. Interim analysis of the effects of exenatide treatment on A1C, weight and cardiovascular risk factors over 82 weeks in 314 overweight patients with type 2 diabetes. https://pubmed.ncbi.nlm.nih.gov/16776751/
  6. van Can J, Sloth B, Jensen CB, Flint A, Blaak EE, Saris WH. Effects of the once-daily GLP-1 analog Liraglutide peptide on gastric emptying, glycemic parameters, appetite and energy metabolism in obese, non-diabetic adults. Int J Obes (Lond). 2014 Jun;38(6):784-93. doi: 10.1038/ijo.2013.162. Epub 2013 Sep 3. PMID: 23999198; PMCID: PMC4052428. https://pmc.ncbi.nlm.nih.gov/articles/PMC4052428/
  7. Drucker DJ. Mechanisms of Action and Therapeutic Application of Glucagon-like Peptide-1. Cell Metab. 2018 Apr 3;27(4):740-756. doi: 10.1016/j.cmet.2018.03.001. PMID: 29617641. https://pubmed.ncbi.nlm.nih.gov/29617641/
  8. Tandong Yang, Meng Chen, Jeffrey D. Carter, Craig S. Nunemaker, James C. Garmey, Sarah D. Kimble, Jerry L. Nadler, Combined treatment with lisofylline and exendin-4 reverses autoimmune diabetes, Biochemical and Biophysical Research Communications, Volume 344, Issue 3,  2006, Pages 1017-1022, ISSN 0006-291X, https://www.sciencedirect.com/science/article/pii/S0006291X06007066)
  9. Bose AK, Mocanu MM, Carr RD, Brand CL, Yellon DM. Glucagon-like peptide 1 can directly protect the heart against ischemia/reperfusion injury. Diabetes. 2005. https://pubmed.ncbi.nlm.nih.gov/15616022/
  10. Nikolaidis LA, Elahi D, Hentosz T, Doverspike A, Huerbin R, Zourelias L, Stolarski C, Shen YT, Shannon RP. Recombinant glucagon-like peptide-1 increases myocardial glucose uptake and improves left ventricular performance in conscious dogs with pacing-induced dilated cardiomyopathy. Circulation. 2004 Aug 24;110(8):955-61. https://pubmed.ncbi.nlm.nih.gov/15313949/
  11. During MJ, Cao L, Zuzga DS, Francis JS, Fitzsimons HL, Jiao X, Bland RJ, Klugmann M, Banks WA, Drucker DJ, Haile CN. Glucagon-like peptide-1 receptor is involved in learning and neuroprotection. Nat Med. 2003 Sep; https://pubmed.ncbi.nlm.nih.gov/12925848
  12. Perry T, Haughey NJ, Mattson MP, Egan JM, Greig NH. Protection and reversal of excitotoxic neuronal damage by glucagon-like peptide-1 and exendin-4. J Pharmacol Exp Ther. 2002 Sep;302(3):881-8. doi: 10.1124/jpet.102.037481. PMID: 12183643. https://pubmed.ncbi.nlm.nih.gov/12183643/
Modified GRF 1-29 & Ipamorelin Blend: Studies in Growth Hormone Secretion and Metabolic Regulation

Modified GRF 1-29 & Ipamorelin Blend: Studies in Growth Hormone Secretion and Metabolic Regulation

The Modified GRF 1-29 and Ipamorelin blend represents a significant advancement in peptide-based research, particularly for its potential to influence growth hormone secretion and metabolic processes. This synergistic combination pairs two complementary peptides with distinct but interconnected roles, which is considered pivotal in this branch of scientific research.

Modified GRF 1-29, a stabilized analog of growth hormone-releasing hormone (GHRH), is reportedly designed to increase growth hormone release by targeting GHRH receptors on somatotroph cells in the anterior pituitary gland.[1] Its structural modifications, which replace four amino acids in the native sequence, are speculated to confer enhanced stability and bioavailability, potentially making it more resistant to enzymatic degradation.

Ipamorelin, a synthetic pentapeptide and selective growth hormone secretagogue (GHS), is suggested to operate by mimicking the action of ghrelin, a naturally occurring hormone involved in hunger signaling and growth hormone release. By activating growth hormone secretagogue receptor 1-alpha (GHS-R1a) in the pituitary, Ipamorelin reportedly initiates intracellular signaling pathways that stimulate the secretion of growth hormone while maintaining high selectivity to avoid affecting other hormones such as cortisol or prolactin.

Together, these peptides are speculated to offer a powerful mechanism of action where Ipamorelin may provide rapid, short-term stimulation of growth hormone release, while Modified GRF 1-29 may ensure a more sustained response by activating complementary signaling pathways. This dual-action mechanism, achieved through distinct receptor interactions, might create an extended-release profile that researchers suggest may lead to increased growth hormone activity compared to studying either peptide alone.[2]

 

Scientific Research and Studies

 

Modified GRF 1-29 & Ipamorelin Blend and Growth Hormone

A series of studies[3] conducted in 1998 appears to provide critical insights into the function of the Modified GRF 1-29 and Ipamorelin blend in the function of growth hormone secretion. Experimental models, including rat pituitary glands, anesthetized rats, and conscious swine, were utilized to evaluate the peptides’ activity. Findings suggest that both Modified GRF 1-29 and Ipamorelin may act as agonists of GHRP-like receptors, binding to these targets to reportedly stimulate significant increases in growth hormone secretion. It also appears that the peptides exhibited high receptor specificity. While other growth hormone secretagogues often triggered elevations in additional hormones such as cortisol and ACTH, Ipamorelin and Modified GRF 1-29 “very surprisingly, did not [appear to] release ACTH or cortisol in levels significantly”, reportedly even at significantly high concentrations compared to other similar peptides.

Further research in 1999 sought to extend these findings through clinical trials. In this study,[4] eight research models were introduced with growth hormone secretagogues at progressively increasing concentrations, with amounts adjusted every 15 minutes over a two-hour period. Based on the results, it was suggested that there was a marked elevation in circulating growth hormone levels throughout the study duration, suggesting a concentration-dependent response to the blend.

These findings support the hypothesis that the combination of Modified GRF 1-29 and Ipamorelin may provide a synergistic and sustained increase of growth hormone release, laying the groundwork for future research into their potential.

 

Cardiac Function

In a pilot study,[5] experimental models were introduced with growth hormone-releasing hormone (GHRH) peptide analogs, including Modified GRF 1-29, to evaluate their potential effects on cardiac function. Findings from this research suggest that the peptides may positively influence myocardial function, particularly in models of myocardial infarction. The study hypothesized that Modified GRF 1-29 might enhance cardiac performance by increasing heart rate and improving blood pumping efficiency.

 

Modified GRF 1-29 & Ipamorelin Blend and Potency

Preliminary investigations have provided significant hypotheses into the potency of the Modified GRF 1-29 and Ipamorelin blend, specifically its potential compared to regular GRF 1-29. In one study,[6] experimental rats were exposed to GHRH peptide analogs, including Modified GRF 1-29. Results suggested that the synthetic analog may have greater efficacy in stimulating growth hormone release than its unmodified counterpart. This enhanced potency appears to be attributed to the structural modifications in Modified GRF 1-29, which may improve its stability and receptor binding efficiency, allowing for sustained biological activity over time.

 

Modified GRF 1-29 & Ipamorelin Blend and the Pituitary

The efficacy of the blend in promoting growth hormone secretion is closely linked to its interaction with GHRH receptors on somatotroph cells in the anterior pituitary gland. The binding of the peptide to these receptors is hypothesized to act as a catalyst for a cascade of intracellular signaling events. One such pathway involves the activation of adenylyl cyclase, which converts ATP into cyclic adenosine monophosphate (cAMP). The elevation of cAMP levels activates protein kinase A (PKA), leading to the phosphorylation of proteins, such as voltage-dependent calcium channels on the somatotroph cell membrane.[7] This phosphorylation facilitates calcium ion influx, which reportedly initiates the secretion of growth hormone from the cell’s secretory vesicles into the bloodstream.

Similarly, Ipamorelin appears to function with a distinct mechanism of action by selectively targeting the GHS-R1a receptors in the anterior pituitary. The peptide supposedly interacts with the N-terminal region of these receptors through hydrogen bonding and van der Waals forces, inducing conformational changes that activate intracellular G-protein signaling pathways. Specifically, GHS-R1a is thought to couple with Gαq/11 subunits, which subsequently activate phospholipase C (PLC). PLC cleaves phosphatidylinositol 4, 5-bisphosphate (PIP2) into two critical secondary messengers: inositol trisphosphate (IP3) and diacylglycerol (DAG). IP3 binds to receptors on the endoplasmic reticulum, prompting the release of calcium ions (Ca2+), which, in turn, reportedly activates downstream proteins that regulate growth hormone secretion.[8]

 

Modified GRF 1-29 & Ipamorelin Blend and the Gastrointestinal System

In a recent investigation, the potential influence of Ipamorelin on gastric motility was examined, with particular emphasis on its capacity to expedite gastric emptying. The study utilized a specialized technique to assess gastric emptying by quantifying the percentage of radioactivity remaining in the stomach 15 minutes following the introduction of a radiolabeled substance via intragastric gavage. The researchers observed that surgical manipulation of the abdominal region may have contributed to a delayed gastric emptying rate, as reported by the researchers in the control group, which received a vehicle substance. In contrast, Ipamorelin appeared to significantly accelerate the gastric emptying process relative to the control group, suggesting that Ipamorelin may potentially increase the rate of gastric emptying.

Subsequent analyses studied the possible effect of Ipamorelin on the contractile activity of gastric smooth muscle, which was induced by both acetylcholine and electrical field stimulation. The results suggested that surgical intervention and manipulation of the gastrointestinal tract in these animal models may markedly attenuate the contractile responses of gastric smooth muscle to these stimuli. Notably, this suppression appeared to be reversed when both Ipamorelin and ghrelin were co-introduced, hinting that Ipamorelin may not only facilitate gastric smooth muscle contractility but also potentially mitigate any inhibitory effects induced by certain surgical interventions.[9]

 

Modified GRF 1-29 & Ipamorelin Blend and Appetite Regulation

The potential effects of Ipamorelin on ghrelin receptors suggest a potential for appetite support and subsequent weight increase In a controlled study,[10] experimental models reportedly “induced a small (15%) increase in body weight by 2 weeks” following peptide exposure. Researchers propose that this compound may have disproportionately increased fat pad mass relative to total body mass, which may lead to a discernible rise in fat as measured by dual-energy X-ray absorptiometry (DEXA). Further data indicated that Ipamorelin may have elevated serum leptin levels, a hormone associated with energy balance and appetite regulation. This observation has led to the hypothesis that increased food intake may play a role in the observed weight gain in the Ipamorelin-exposed research models. The researchers suggest that growth hormone secretagogues (GHSs), such as Ipamorelin, may contribute to fat cell accumulation via mechanisms independent of growth hormone, potentially including an increase in caloric consumption.

 

Modified GRF 1-29 & Ipamorelin Blend and Bone Density

In a study conducted with murine models, the effects of Ipamorelin on bone mass were evaluated through the introduction of both Ipamorelin and a control substance. Real-time DEXA was utilized to monitor alterations in bone mineral content, focusing on specific regions such as the femur and L6 vertebrae. Upon completion of the experimental period, mid-diaphyseal peripheral quantitative computed tomography (pQCT) scans were performed on the femurs of the models under observation. Preliminary findings suggest that Ipamorelin may be associated with an increase in weight and a potential rise in bone mineral content (BMC) in the tibia and vertebrae, as indicated by DEXA results when compared to the control group. Moreover, pQCT data point to an increase in cortical BMC, likely due to an expansion of the bone’s cross-sectional area. The researchers also hypothesize that minor stimulatory effects on linear bone growth may not have been statistically significant in the growth hormone (GH) and Ipamorelin-exposed cohorts, potentially due to the scope of the study.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

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  5. Schally AV, Zhang X, Cai R, Hare JM, Granata R, Bartoli M. Actions and Potential Therapeutic Applications of Growth Hormone-Releasing Hormone Agonists. Endocrinology. 2019 Jul 1;160(7):1600-1612. doi: 10.1210/en.2019-00111. PMID: 31070727. https://pubmed.ncbi.nlm.nih.gov/31070727/
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  11. Image 1 source: National Center for Biotechnology Information. PubChem Compound Summary for CID 91976842, CJC1295 Without DAC. https://pubchem.ncbi.nlm.nih.gov/compound/CJC1295-Without-DAC
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