CJC-1295 No DAC: Modified GHRH Analog Research Overview
CJC-1295 No DAC is a synthetic peptide based on the active 1-29 amino acid sequence of growth hormone-releasing hormone (GHRH), engineered with four amino acid substitutions to enhance enzymatic stability. The 'No DAC' designation distinguishes this variant from CJC-1295 with DAC, which includes an additional drug affinity complex linker for extended half-life. This page summarizes the published preclinical research on CJC-1295 No DAC's structure and laboratory applications.
Background
CJC-1295 is the designation for a class of GHRH analogs developed at ConjuChem (the 'CJ' prefix). The compound family was designed to address the short half-life of native GHRH by introducing residue substitutions that resist enzymatic degradation. CJC-1295 exists in two main forms: 'with DAC' (with a drug affinity complex linker) and 'without DAC' (without the linker).[1]
CJC-1295 No DAC is based on GHRH(1-29), the truncated active fragment of full-length 44-amino-acid GHRH. The peptide carries four substitutions at positions known to be susceptible to proteolytic cleavage. This is the same backbone as Modified GRF (1-29), and the two designations are often used interchangeably in research literature.[2]
CJC-1295 No DAC is studied as a research reference compound. It has not been approved by the FDA for any human therapeutic, diagnostic, or medical purpose.
Chemistry & Structure
CJC-1295 No DAC is based on the GHRH(1-29) sequence with four amino acid substitutions:
- Base sequence: Modified GRF(1-29) — based on hGHRH(1-29)
- Substitutions: D-Ala at position 2, Gln at position 8, Ala at position 15, Leu at position 27
- Length: 29 amino acids
- Molecular formula: C₁₅₂H₂₅₂N₄₄O₄₂
- Molecular weight: approximately 3,367 Da
The substitution rationale
Each of the four substitutions targets a specific enzymatic vulnerability:
- Position 2 (D-Ala): protects against dipeptidyl peptidase-4 (DPP-4) cleavage at the N-terminus, a primary degradation pathway for native GHRH
- Position 8 (Gln): replaces an asparagine residue prone to deamidation
- Position 15 (Ala): replaces a glycine residue, contributing to backbone stability
- Position 27 (Leu): replaces a methionine residue, reducing susceptibility to oxidation
Distinction from CJC-1295 with DAC
The 'No DAC' variant lacks the drug affinity complex linker present on CJC-1295 (DAC), which is a maleimidopropionyl-Lys group that reversibly binds serum albumin. This linker extends half-life dramatically (days vs hours) in vivo. Research applications often choose No DAC when pulsatile GH release pattern preservation is desired, since DAC's continuous receptor activation can blunt pulsatility.[3]
Receptor Pharmacology
CJC-1295 No DAC acts at the GHRH receptor (GHRHR) on pituitary somatotrophs, like its parent GHRH(1-29).
GHRHR binding and signaling
Binding affinity at GHRHR is preserved in CJC-1295 No DAC despite the four amino acid substitutions, since the substitutions target degradation-prone residues rather than receptor-binding determinants. Downstream cAMP signaling and GH release in pituitary cell models proceed as with native GHRH.[1][4]
Pulsatile GH stimulation
Because CJC-1295 No DAC has a moderately extended half-life relative to native GHRH (driven by the four substitutions) but not the dramatic extension of the DAC variant, preclinical studies note that the No DAC form supports more physiological pulsatile GH release patterns than the DAC variant.[3]
Documented Preclinical Research Areas
CJC-1295 No DAC research has been concentrated in several preclinical domains.
Combination with Ipamorelin
The CJC-1295 No DAC + Ipamorelin pairing is among the most-studied preclinical peptide combinations in growth hormone secretagogue research. The combination targets the GHRHR and GHS-R1a receptor systems in parallel.[4]
Pituitary signaling studies
Pituitary slice preparations and cell cultures expressing GHRHR are used to characterize CJC-1295 No DAC potency, efficacy, and receptor binding kinetics in standard pharmacology assays.[1]
Comparison studies with other GHRH analogs
Sermorelin, Tesamorelin, and CJC-1295 (both forms) are typically compared head-to-head in GHRH-analog research. CJC-1295 No DAC sits between Sermorelin (short half-life) and CJC-1295 DAC (long half-life) on the pharmacokinetic spectrum, making it useful for studies probing the relationship between dosing regimen and response.[5]
Stability & Handling
CJC-1295 No DAC's four substitutions provide enhanced stability over native GHRH, but storage and reconstitution still follow standard practices for synthetic peptides.
Storage
Lyophilized CJC-1295 No DAC is stored at minus 20 degrees Celsius for long-term preservation. Brief refrigerated storage at 4 degrees Celsius is acceptable for actively used material.
Reconstitution
Bacteriostatic water is the standard reconstitution solvent for research preparations. Reconstituted solution is used within 4 to 6 weeks at 4 degrees Celsius.
Quality verification
Quality is verified by HPLC for purity (greater than or equal to 99 percent), mass spectrometry for identity confirmation matching the substituted 29-residue mass, and endotoxin testing. Each batch of Instant Peptides CJC-1295 No DAC ships with a full Certificate of Analysis.
Available Research Material
Instant Peptides supplies CJC-1295 No DAC as a synthetic lyophilized reference compound in 5mg vials. Material is supplied to qualified research professionals and scientific institutions. Not for human or animal consumption.
View the product page for current pricing and the Certificate of Analysis for the active batch.
Available Research Material
CJC-1295 No DAC
Lyophilized synthetic reference compound. Independently tested for purity by HPLC and mass spectrometry. Full Certificate of Analysis included.
View product detailsReferences
- 1.Teichman SL, Neale A, Lawrence B, et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295. Journal of Clinical Endocrinology & Metabolism. 2006. PMID: 16352683
- 2.Sigalos JT, Pastuszak AW. The Safety and Efficacy of Growth Hormone Secretagogues. Sexual Medicine Reviews. 2018. PMID: 28526632
- 3.Ionescu M, Frohman LA. Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GHRH analog. Journal of Clinical Endocrinology & Metabolism. 2006. PMID: 16968794
- 4.Alba M, Fintini D, Sagazio A, et al. Once-daily administration of CJC-1295, a long-acting growth hormone-releasing hormone (GHRH) analog, normalizes growth in the GHRH knockout mouse. American Journal of Physiology - Endocrinology and Metabolism. 2006. PMID: 16464908
- 5.Frohman LA, Kineman RD. Growth hormone-releasing hormone: discovery, regulation, and actions. Endocrinology. 1996. PMID: 8531116