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Cjc-1295 Structure And Mechanism — Practical Notes

By Editorial Desk · published 2026-07-14 · last reviewed 2026-07-31 · Data

Everything below concerns Reversed-phase HPLC. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.

Updated 2026-07-31. Numbers and descriptions here follow the published literature rather than marketing material.

CJC-1295 Structure And Mechanism

Binding to GHRH receptors on pituitary somatotroph cells triggers cyclic AMP signaling and stimulates growth hormone synthesis and release. Because the peptide acts upstream of the pituitary, effects are mediated through endogenous growth hormone rather than direct receptor activation in peripheral tissues. Increases in insulin-like growth factor 1 are generally described as a downstream consequence. Most published human exposure data come from small early-stage studies, and the clinical significance of the pharmacokinetic profile remains incompletely characterized.

CJC-1295 is a synthetic analogue of growth hormone-releasing hormone, built on the 29-amino-acid GHRH(1-29) fragment. Four substitutions distinguish it from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes reduce enzymatic cleavage and extend the peptide's persistence in circulation. The compound is discussed in two forms, one carrying a drug affinity complex and one without it.

The drug affinity complex is a maleimidopropionic acid group attached to a lysine side chain. It reacts with the free thiol of cysteine-34 on circulating albumin, forming a covalent bond. This conjugation keeps the peptide in the bloodstream and shields it from rapid renal filtration and proteolysis. Reported circulation half-lives for the albumin-bound form fall in the range of roughly six to nine days in early human studies.

Handling Storage And Analytical Methods

Research material is normally supplied as a freeze-dried powder in sealed vials. In that state the peptide is comparatively robust, but prolonged exposure to warmth, moisture, or light accelerates degradation. Storage at minus twenty degrees Celsius or lower, with desiccant and protection from light, is the commonly described practice. Vials should be allowed to reach room temperature before opening to limit condensation on the powder. Moisture uptake during handling is a recognized source of variability in later measurements.

Reconstitution is typically performed with sterile water or bacteriostatic water, added slowly against the vial wall. The resulting solution should be clear and colorless; cloudiness or visible particles suggest a problem with the material or the diluent. Once in solution, the peptide is less stable than the dry powder. Refrigerated storage at two to eight degrees Celsius is common for short-term holding, while freezing aliquots is described for longer periods.

Purity is most often assessed by reversed-phase high-performance liquid chromatography, reported as a percentage of total peak area. Identity is confirmed by mass spectrometry, which yields a molecular ion consistent with the expected sequence. Amino acid analysis and peptide mapping provide additional characterization. Reported purity values are method-dependent, so figures from different laboratories are not always directly comparable without details of column, gradient, and detection wavelength.

Cjc-1295 at a glance

PropertyValueNotes
Physical formLyophilized white powderSupplied as a freeze-dried solid for research use
Molecular weightApproximately 3,647 Da (DAC form)Lower for the variant lacking the albumin-binding moiety
SolubilitySoluble in water and aqueous bufferTypically dissolved in sterile or bacteriostatic water
Typical storage temperature−20 °C or belowDry powder, desiccated and protected from light
Common analytical methodReversed-phase HPLC with mass spectrometryUsed for purity estimation and identity confirmation

Background and Molecular Design

CJC-1295 belongs to a family of synthetic peptides modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound is built from the first twenty-nine amino acids of the natural human sequence, a fragment that retains full receptor binding capacity. Native growth hormone-releasing hormone is degraded quickly in circulation, so the fragment alone has limited practical value. Early work therefore focused on chemical modifications that preserve receptor binding while slowing enzymatic breakdown. The result is a molecule described in the literature as a long-acting analog of the natural hormone.

Two forms circulate under the CJC-1295 name, and they differ by a single appended group. The version without a drug affinity complex carries four substitutions along the peptide chain, including a D-alanine near the amino terminus and replacements at three other positions. These changes block the enzyme dipeptidyl peptidase IV and remove a methionine residue that is prone to oxidation. The modified fragment is frequently labeled MOD GRF 1-29. Naming conventions are inconsistent across informal sources, which is a common source of confusion.

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Persistence, Stability and Measurement

Lyophilized peptide powder is comparatively stable when kept dry, cold, and protected from light. Once dissolved, the molecule is vulnerable to deamidation, oxidation, and aggregation, with the rate depending on pH, buffer composition, and temperature. Alkaline conditions and repeated freeze-thaw cycles accelerate loss of the intact peptide. The methionine present in the native sequence is a known oxidation site, which is one reason it was replaced in the modified fragment. Suppliers typically recommend cold storage of solutions and use within a short window.

Analytical confirmation usually relies on reversed-phase high-performance liquid chromatography for purity and on liquid chromatography coupled to mass spectrometry for identity. Mass data reveal the expected molecular mass and can flag truncated or oxidized species. Amino acid analysis and peptide mapping provide sequence-level verification. Immunoassays are used in some biological matrices, but antibodies raised against one releasing-hormone analog may cross-react with another. Reported purity figures depend heavily on the method used, so comparisons between suppliers require matching the analytical approach.

Structure And Receptor Pharmacology

Receptor level activity follows the canonical GHRH pathway. The peptide binds the GHRH receptor, a class B G protein coupled receptor on somatotroph cells of the anterior pituitary. Binding raises intracellular cyclic AMP, which promotes calcium entry and the release of growth hormone into the bloodstream. Because the molecule acts at the same receptor as the endogenous hormone, its effect is superimposed on the natural pulsatile rhythm rather than replacing it. Whether sustained receptor occupation leads to desensitization is not fully settled.

CJC-1295 belongs to a class of synthetic peptides modeled on growth hormone releasing hormone, a forty-four amino acid signal produced by the hypothalamus. The compound is built from the first twenty-nine residues of the natural sequence, with four substitutions introduced at positions 2, 8, 15 and 27. These changes were designed to slow enzymatic breakdown while preserving receptor activation. The result is a peptide that is shorter than native GHRH and considerably more resistant to ordinary clearance pathways in circulation.

Analytical Measurement And Stability

Lyophilized material is generally stable for extended periods when held at minus twenty degrees Celsius or below and protected from moisture and light. In solution the peptide is more labile; bond hydrolysis, aggregation and oxidation of susceptible residues all proceed faster at ambient temperature. Repeated freeze and thaw cycles should be avoided because they promote clumping and loss of soluble material. The conjugated variant adds a further consideration, since the maleimide group can hydrolyze in aqueous buffer and lose its ability to react with albumin.

Laboratory handling centers on minimizing exposure to water, heat and oxygen before use. Working solutions are typically prepared in sterile water or a mild buffer, and any residual particulate matter is removed by filtration. When the powder dissolves slowly, a small proportion of acetonitrile or dilute acetic acid is sometimes added as a co-solvent. Containers are kept sealed and desiccated between uses. Records of lot number, reconstitution date and storage conditions support later comparison of results across experiments.

Notes from published material

==== Pregnancy and breastfeeding ==== The metabolism of caffeine is reduced in pregnancy, especially in the third trimester, and the half-life of caffeine during pregnancy can be increased up to 15 hours (as compared to 2.5 to 4.5 hours in non-pregnant adults). Evidence regarding the effects of caffeine on pregnancy and for breastfeeding are inconclusive. There is limited primary and secondary advice for, or against, caffeine use during pregnancy and its effects on the fetus or newborn. The UK Food Standards Agency has recommended that pregnant women should limit their caffeine intake, out of prudence, to less than 200 mg of caffeine a day – the equivalent of two cups of instant coffee, or one and a half to two cups of fresh coffee. The American Congress of Obstetricians and Gynecologists (ACOG) concluded in 2010 that caffeine consumption is safe up to 200 mg per day in pregnant women. For women who breastfeed, are pregnant, or may become pregnant, Health Canada recommends a maximum daily caffeine intake of no more than 300 mg, or a little over two 8 oz (237 mL) cups of coffee. A 2017 systematic review on caffeine toxicology found evidence supporting that caffeine consumption up to 300 mg/day for pregnant women is generally not associated with adverse reproductive or developmental effect. There are conflicting reports in the scientific literature about caffeine use during pregnancy.

It is not entirely clear why doxepin and first-generation antihistamines are different in this regard, but it has been suggested that it may have to do with the lack of selectivity for the H1 receptor of the latter or may have to do with the use of optimal doses. Unlike very-low-dose doxepin, most first-generation antihistamines also have marked anticholinergic activity as well as associated side effects such as dry mouth, constipation, urinary retention, and confusion. This is particularly true in older people, and antihistamines with concomitant anticholinergic effects are not recommended in adults over the age of 65. Anticholinergic activity notably may interfere with the sleep-promoting effects of H1 receptor blockade. Antagonism of the H1, 5-HT2A, 5-HT2C, and α1-adrenergic receptors is thought to have sleep-promoting effects and to be responsible for the sedative effects of TCAs including those of doxepin. Although doxepin is selective for the H1 receptor at doses lower than 25 mg, blockade of serotonin and adrenergic receptors may also be involved in the hypnotic effects of doxepin at higher doses. However, in contrast to very low doses of doxepin, rebound insomnia and daytime sedation are significantly more frequent than placebo with moderate doses (25 to 50 mg/day) of the drug. In addition, one study found that although such doses of doxepin improved sleep measures initially, most of the benefits were lost with chronic treatment (by 4 weeks).

In a social media post, former First Minister of Scotland Nicola Sturgeon announces that she and Peter Murrell, the former SNP chief executive, have "decided to end" their marriage and have been separated for some time. According to Reform UK's website they now have 180,000 members. 14 January – Tulip Siddiq resigns as Economic Secretary to the Treasury, over a scandal linked to the ousted government of Bangladesh. She becomes the second minister to resign from the Starmer ministry since the general election of July 2024. Emma Reynolds is appointed to replace her. Helen Pitcher resigns as chair of the Criminal Cases Review Commission following criticism from government regarding her tenure in charge of the Commission, and moves to have her removed from the post. Welsh Conservative leader Darren Millar accuses Senedd Presiding Officer Elin Jones of "inappropriately interrupting him" after she tells him to "tone down" a question about grooming gangs while he called for a fresh inquiry into child sexual abuse. 15 January – Prime Minister Keir Starmer tells the House of Commons the UK government will look at "every conceivable way" to prevent Gerry Adams, the former President of Sinn Féin, from receiving compensation after it emerged that repealing the Troubles Legacy Act could allow him to claim compensation for unlawful detention during the 1970s. Education Secretary Bridget Phillipson tells Parliament the UK government will proceed with the Higher Education (Freedom of Speech) Act 2023, which proposed fines for universities failing to uphold freedom of speech.

==== Andrea Cozzolino ==== Andrea Cozzolino's legal immunity was also removed by the European Parliament on 2 February 2023, when Andrea Cozzolino was in Italy. Cozzolino was arrested on 10 February 2023, after leaving a hospital in Naples where he was being treated for heart problems; he was taken to Poggioreale prison, but later allowed to go home under house-arrest. Cozzolino's lawyer Dimitri De Béco issued a statement that Cozzolino opposed being extradited to Belgium, because of the Belgian justice "way of proceeding". Cozzolino has repeatedly denied any wrong-doing. On 14 February, a Naples court granted a request from Cozzolino's lawyers to postpone the extradition hearing to 28 February so that the court could check the prison in Belgium that Cozzolino would be put in if extradited. In June he flew to Brussels and was placed by a Judge on parole, with conditions attached.

Sources: en.wikipedia.org

Background from the literature

=== Hypertension === Hypertension is a chronic elevation of arterial blood pressure that increases the risk of cardiovascular disease and organ damage. Many people with essential hypertension experience increased sympathetic nervous system activity, in addition to renin–angiotensin–aldosterone system activation. Clonidine is a non-selective α2 adrenoreceptor and imidazoline receptor agonist that reduces sympathetic nervous system output from the brainstem, which lowers peripheral vascular resistance, heart rate and plasma renin activity, thereby reducing systolic and diastolic blood pressure as a consequence. Meta-analyses of randomized controlled trials in arterial hypertension have found that clonidine is an effective antihypertensive that leads to greater reductions in systolic and diastolic blood pressure than placebo. A 2024 network meta-analysis of imidazoline receptor agonists (i.e., moxonidine and clonidine) reported that this drug class produced ambulatory blood pressure reductions that were close in magnitude to those of commonly used first-line antihypertensive drug classes, but with higher odds of adverse effects such as dry mouth and sedation, especially with clonidine. Hypertension Canada's 2020 clinical practice guideline on resistant hypertension similarly notes that clonidine significantly lowers blood pressure in clinical trials, though it is considered a second-line therapy due to its potential for side effects.

Also, no evidence exists that rBST use has increased human exposure to antibiotic residues in milk. Concerns that IGF-1 present in milk could have biological effects on humans have been allayed by studies showing that oral consumption of IGF-1 by humans has little or no biological activity. Additionally, concentrations of IGF-1 in digestive tract fluids of humans far exceed any IGF-1 consumed when drinking milk. Furthermore, chronic supplementation of cows with rBST does not increase concentrations of milk IGF-1 outside the range typically observed for effects of farm, parity, or stage of lactation. Use of rBST has not affected expression of retroviruses in cattle or posed an increased risk to human health from retroviruses in cattle. Furthermore, risk for development of type 1 or type 2 diabetes mellitus has not increased in children or adults consuming milk and dairy products from rBST-supplemented cows. Overall, milk and dairy products provide essential nutrients and related benefits in health maintenance and the prevention of chronic diseases." Keeping in mind that bovine somatotropin is a protein growth hormone, it can increase average milk yield anywhere from 10 to 15%, which in turn would lead to cows consuming substantially more nutrients in order to keep up with the increased milk production. Most of a cow's energy consumption goes directly towards milk production.

Representative Melanie Stansbury official U.S. House website Campaign website Biography at the Biographical Directory of the United States Congress Financial information (federal office) at the Federal Election Commission Legislation sponsored at the Library of Congress Profile at Vote Smart Appearances on C-SPAN

Females – Ovariole number is significantly affected by developmental temperature in D. melanogaster. Egg size is also affected by developmental temperature, and exacerbated when both parents develop at warm temperatures (See Maternal effect). Under stressful temperatures, these structures will develop to smaller ultimate sizes and decrease a female's reproductive output. Early fecundity (total eggs laid in first 10 days post-eclosion) is maximized when reared at 25 °C (versus 17 °C and 29 °C) regardless of adult temperature. Across a wide range of developmental temperatures, females tend to have greater heat tolerance than males. Males – Stressful developmental temperatures will cause sterility in D. melanogaster males; although the upper temperature limit can be increased by maintaining strains at high temperatures (See acclimation). Male sterility can be reversible if adults are returned to an optimal temperature after developing at stressful temperatures. Male flies are smaller and more successful at defending food/oviposition sites when reared at 25 °C versus 18 °C; thus smaller males will have increased mating success and reproductive output.

In August 2015 it was announced that Interpol now offers a dedicated Dark Web training program featuring technical information on Tor and cybersecurity and simulated darknet market takedowns. In October 2015 the UK's National Crime Agency and GCHQ announced the formation of a "Joint Operations Cell" to focus on cybercrime. In November 2015 this team would be tasked with tackling child exploitation on the dark web as well as other cybercrime. In February 2015, the EMCDDA produced another report citing the increased importance of customer service and reputation management in the marketplace, the reduced risk of violence and increased product purity. It estimated a quarter of all purchases were for resale and that the trend towards decentralization meant they are unlikely to be eliminated any time soon. A June 2016 report from the Global Drug Survey described how the markets are increasing in popularity, despite ongoing law enforcement action and scams. Other findings include consumers making purchases via friends operating Tor browser and Bitcoin payments, rather than directly. Access to markets in 79% of respondents' cases led to users trying a new type of drug. A 2017 study focused on a geographical analysis of trafficking on a darknet market. Researchers contended that previous studies have demonstrated variations in the types of substances available in different countries.

Sources: en.wikipedia.org

Frequently asked questions

How does CJC-1295 differ from modified GRF(1-29)?

The two share the same 29-amino-acid backbone. CJC-1295 carries an additional albumin-binding moiety that markedly extends its residence time in circulation, while the form without that moiety clears faster. Literature sometimes applies the name loosely to either variant.

Is CJC-1295 an approved medicine?

It has not been approved by major regulatory agencies for any therapeutic indication. Material sold under this name is typically distributed for laboratory research only. Clinical use is not supported by large controlled trials.

What is known about its half-life?

Early human studies of the albumin-binding form reported circulation half-lives on the order of several days. The value depends on assay method and study design. Estimates for the form without the binding moiety are considerably shorter.

How should the dry powder be stored?

Cool, dark, and dry conditions are standard, with storage at minus twenty degrees Celsius or below. Desiccant and sealed vials limit moisture uptake. Repeated warming and cooling of the container is generally avoided.

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