The synthetic peptide CJC-1295 DAC is a modified form of growth hormone-releasing hormone (GHRH) designed to prolong GHRH receptor activation in the anterior pituitary of an organism. Originally developed by ConjuChem Biotechnologies, it incorporates an Affinity Complex (DAC) moiety, which may bind to serum albumin and thereby extend its half-life significantly compared to short-acting GHRH analogs. This article reviews suggested mechanistic features of CJC-1295 DAC.
Biochemical and Pharmacokinetic Properties
CJC-1295 DAC is an analog of GHRH (1-29) with amino-acid modifications and a conjugated DAC moiety. The DAC component is believed to bind to albumin, thereby reducing renal clearance and enzymatic degradation of the peptide, leading to a substantially prolonged half-life in circulation. In one investigation, the half-life of CJC-1295 was estimated at approximately 5.8–8.1 days in mature mammalian research models. The extended exposure, in turn, appeared to have resulted in elevated plasma concentrations of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) for several days after a single concentration.
Mechanistically, CJC-1295 DAC is theorized to bind to GHRH receptors on somatotroph cells of the anterior pituitary, stimulating endogenous GH secretion, which may then increase IGF-1 production by the liver (or other IGF-1-producing tissues) in the research model. Importantly, one investigation indicated that exposure to CJC-1295 did not seem to alter the frequency or amplitude of GH secretory pulses, but rather elevated basal (trough) GH concentrations and thus increased mean GH over time, while preserving pulsatility.
Research Domains and Possible Implications
Studies suggest that, given its pharmacologic profile, CJC-1295 DAC may be of interest across multiple research domains. The following sections outline several key areas where investigations might leverage this peptide’s properties to probe physiology, mechanism, and potential translational pathways.
- Growth, Development, and Tissue Homeostasis
The GH/IGF-1 axis is central to growth and development in many mammalian research models, regulating cellular proliferation, differentiation, and tissue maintenance. With CJC-1295 DAC’s potential to prolong GH and IGF-1 elevation, researchers may use it to study how sustained GH axis activation impacts growth-associated processes in various tissues (bone, muscle, connective tissue) in research models. For example, the potential to maintain elevated IGF-1 over weeks may allow exploration of how tissue homeostasis adapts to persistent GH/IGF-1 stimulation — for instance, changes in receptor expression, downstream signaling, or stromal-cell responses over time.
- Metabolic and Energy Homeostasis Research
GH and IGF-1 have well-characterized roles in metabolic regulation — including lipolysis (fat mobilization), protein synthesis, glucose homeostasis, and organ-specific metabolic shifts. Research indicates that by utilizing CJC-1295 DAC in research models, investigators might explore how sustained augmentation of GH/IGF-1 supports lipid turnover, insulin sensitivity, and energy partitioning. For instance, one might examine whether persistent activation of GH release by the peptide shifts the balance between adipose storage and mobilization, or alters hepatic glucose production, mitochondrial function, or muscle protein metabolism.
- Tissue Processes and Cellular Renewal Research
Growth hormone and IGF-1 also play roles in tissue repair and regenerative processes. In research contexts, CJC-1295 DAC is believed to serve as a tool to simulate better-supported GH/IGF-1 signaling and thereby investigate mechanisms of tissue regeneration — for example, muscle repair after induced injury (in research models), cartilage renewal, or extracellular matrix remodeling.
Because the peptide appears to sustain exposure rather than producing sharp transient pulses, it is hypothesized to offer the possibility to examine how extended GH/IGF-1 elevation might support cell proliferation, stem/progenitor cell activation, angiogenesis, and matrix deposition over longer periods. Such work might be relevant to regenerative biology, tissue engineering, or mechanistic studies of recovery from damage.
- Immunity and Cellular Age-Related Physiology
There is growing recognition that GH and IGF-1 may support immune cell proliferation, cytokine production, and aspects of cellular aging. Investigations purport that CJC-1295 DAC may afford researchers a tool to probe how sustained GH axis activation amy support immune-system parameters (e.g., T-cell subsets, NK cell activity, macrophage polarization) or cellular age-related decline in physiological systems.
- Neuroendocrine and Cognitive Research
The GH/IGF-1 axis interacts with neural tissues and may play a role in neurogenesis, synaptic plasticity, and cognition in research settings. With prolonged GH/IGF-1 increase induced by CJC-1295 DAC, investigators might explore whether this alters neuronal proliferation, dendritic branching, neurotrophic signaling, or neuroinflammation in experimental models. For example, whether sustained GH/IGF-1 elevation supports recovery from neural injury or modulates memory-associated circuits remains a speculative but interesting avenue. Findings imply that the peptide may help map the hormonal-neural interface over extended time frames.
- Cardiovascular and Vascular Research
GH and IGF-1 have been implicated in cardiovascular physiology — such as cardiac structure, endothelial function, vascular tone, and lipid metabolism. In research models, the sustained GH/IGF-1 elevation via CJC-1295 DAC has been hypothesized to allow examination of how long-term GH axis activation may impact vascular remodeling, cardiomyocyte growth, fibrosis, or atherogenic processes. For example, researchers might study whether prolonged GH/IGF-1 may support myocardial hypertrophy signaling, vascular smooth-muscle cell behavior, or cholesterol metabolism in controlled settings.
Conclusion
The peptide CJC-1295 DAC represents a powerful research tool for probing the GH/IGF-1 axis in non-laboratory settings. Its unique pharmacokinetic profile — notably a prolonged half-life and sustained elevation of GH and IGF-1 while preserving native pulsatility to some extent — is thought to open diverse possibilities for mechanistic investigations across growth, metabolism, tissue regeneration, cellular aging, neuro-endocrine integration, and cardiovascular physiology. For investigators seeking to explore GH/IGF-1-mediated pathways, this product may constitute a valuable research-grade analog in relevant experimental systems.
References
[i] Teichman, S. L., Neale, A., Lawrence, B., Gagnon, C., Castaigne, J.-P., & Frohman, L. A. (2006). Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I (IGF-I) secretion by CJC-1295, a long‐acting analog of GH‐releasing hormone, in healthy adults. The Journal of Clinical Endocrinology & Metabolism, 91(3), 799-805. https://doi.org/10.1210/jc.2005-1638
[ii] Sackmann-Sala, L., Yamada, S., Berryman, D. E., George, B., Okada, S., & Kopchick, J. J. (2009). Activation of the GH/IGF-1 axis by CJC-1295, a long-acting GHRH analog: proteomic biomarkers of GH/IGF-1 action in healthy adults. Journal of Clinical Endocrinology & Metabolism, 94(10), 4398-4405. https://doi.org/10.1210/jc.2009-0702
[iii] Alberti, K. G. M. M., Riddle, M., & Fienberg, R. (2008). Chemical modification of Class II G-protein coupled receptor ligands: bioconjugation of GHRH analogues including CJC-1295. Peptide Science / PMC, 90(2), 149-161. https://doi.org/10.1002/bip.20866
[iv] Johannsson, G., Marin, P., Lonn, L., Ritzen, E., Bengtsson, B. A., & Sjöström, L. (2006). Pulsatile secretion of growth hormone (GH) persists during administration of CJC-1295, a long-acting growth hormone-releasing hormone analog. The Journal of Clinical Endocrinology & Metabolism, 91(12), 4792-4798. https://doi.org/10.1210/jc.2006-1600
[v] Walker, A. P., & Klein, R. L. (2008). Advances in the detection of growth hormone‐releasing hormone synthetic analogs: in vitro metabolism and analytical challenges including CJC-1295. Drug Testing and Analysis, 2(7/8), 365-372. https://doi.org/10.1002/dta.3183