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Molecular Background And Naming — Explained

By Editorial Desk · published 2025-07-01 · last reviewed 2025-08-14 · Data

lyophilized powder is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.

Updated 2025-08-14. Numbers and descriptions here follow the published literature rather than marketing material.

Molecular Background and Naming

CJC-1295 is a synthetic peptide designed as a long-acting analogue of growth hormone-releasing hormone (GHRH). Its structure derives from the first 29 amino acids of native GHRH, a fragment often called GRF(1-29). Four substitutions were introduced to slow enzymatic breakdown and extend activity relative to the natural sequence. The compound was developed by ConjuChem as part of a broader effort to improve the pharmacokinetic profile of peptide hormones. It is studied in laboratory and clinical research settings rather than appearing as a naturally occurring substance.

Two related forms circulate in technical discussion under the same family name. The original version carries a drug affinity complex (DAC) that binds covalently to serum albumin after administration, and this linkage substantially extends circulation time. A second form, frequently written as modified GRF(1-29) or CJC-1295 without DAC, lacks that linker and clears much faster. The naming is a frequent source of confusion because the shorthand CJC-1295 can refer to either form depending on the source. Reports sometimes fail to specify which variant was studied.

Mechanism and Pharmacokinetics

The albumin-binding version stays in circulation for days, because covalent attachment to serum albumin shields the peptide from rapid filtration and degradation. Reported half-lives for this form fall in the range of several days. The version without the linker is cleared in minutes, with estimates often near thirty minutes in animal work. These figures come from small studies and vary with assay method, species, and route, so they are best read as approximate rather than fixed constants.

Studies in this area generally track growth hormone pulses, insulin-like growth factor 1 concentrations, and occasionally body composition endpoints. Most published human data come from early, small trials, and questions about long-term effects remain open. Whether repeated exposure alters pituitary responsiveness over time is not settled. Analytical work relies on immunoassays for the hormones and on mass spectrometry for the peptide itself, because the two measurements answer different questions.

Binding of the peptide to the growth hormone-releasing hormone receptor on pituitary somatotrophs triggers a G protein coupled cascade that raises cyclic AMP and opens calcium channels. The result is greater secretion of growth hormone into the bloodstream. Because the peptide acts at the same receptor as the natural hypothalamic hormone, its effect is amplified pulse size rather than an entirely separate release pathway. Receptor binding alone does not determine the response, since somatostatin tone and other inputs modulate the final output.

Cjc-1295 at a glance

PropertyValueNotes
Molecular weight (no linker)~3.37 kDaCalculated from peptide sequence
Molecular weight (with linker)~3.65 kDaIncludes albumin-binding moiety
AppearanceWhite to off-white powderTypically lyophilized
SolubilitySoluble in waterAlso dissolves in aqueous buffers
Common synonymsModified GRF(1-29), DAC:GRFUsage varies by source

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.

Two related forms appear under the CJC-1295 name. The simpler analogue, commonly written as modified GRF(1-29), carries the four substitutions but no additional conjugation. The second form attaches a maleimidopropionic acid linker to a lysine residue, a modification frequently called the drug affinity complex. That linker reacts with the free thiol on serum albumin to form a covalent bond. Because albumin has a long residence time in blood, the conjugated peptide stays in circulation far longer than the unconjugated analogue.

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Receptor Action and Pharmacokinetics

The attached maleimide group explains the unusual duration of the DAC version. After injection it reacts with the thiol of cysteine-34 on serum albumin, forming a stable covalent bond. The resulting conjugate is too large for rapid kidney filtration and is shielded from many peptidases. Reported half-lives for this form reach several days, whereas the version without the group is cleared in roughly half an hour. That gap is the main pharmacological difference between the two.

Downstream of growth hormone, the liver and other tissues increase production of insulin-like growth factor 1, a mediator of many growth-promoting effects. Studies have documented elevated levels of both hormones after dosing, and the rise from the long-acting form persists longer than that produced by shorter-acting analogues. What remains unclear is whether sustained elevation of these markers translates into meaningful clinical benefit, and whether prolonged exposure carries risks that short trials could not detect.

CJC-1295 Structure And Mechanism

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.

Background from the literature

About 100,000 protesters occupied Piața Operei (Opera Square – today Piața Victoriei, Victory Square) and chanted anti-government slogans: "Noi suntem poporul!" ("We are the people!"), "Armata e cu noi!" ("The army is on our side!"), "Nu vă fie frică, Ceaușescu pică!" ("Have no fear, Ceaușescu is falling!") Meanwhile, Secretary to the Central Committee Emil Bobu and Prime Minister Constantin Dăscălescu were sent by Elena Ceaușescu (Nicolae being at that time in Iran) to resolve the situation. They met with a delegation of the protesters and agreed to free the majority of the arrested protesters. However, they refused to comply with the protesters' main demand— the resignation of Ceaușescu—and the situation remained essentially unchanged. The next day, trains loaded with workers from factories in Oltenia arrived in Timișoara. The regime was attempting to use them to repress the mass protests, but after a brief encounter they ended up joining the protests. One worker explained, "Yesterday our factory boss and a party official rounded us up in the yard, handed us wooden clubs and told us that Hungarians and 'hooligans' were devastating Timișoara and that it is our duty to go there and help crush the riots.

=== Taxonomy === Rhodiola rosea was first described by Pedanius Dioscorides in De Materia Medica. Many North American plants formerly included in R. rosea are now treated separately as Rhodiola integrifolia and Rhodiola rhodantha.

For an odd-numbered saturated fat (Cn), 0.5 * n - 1.5 oxidations are necessary, and the final process yields 8 acetyl CoA and 1 propionyl CoA. It is then converted to a succinyl CoA by a carboxylation reaction and generates additional 5 ATP (1 ATP is consumed in carboxylation process generating a net of 4 ATP). In addition, two equivalents of ATP are lost during the activation of the fatty acid. Therefore, the total ATP yield can be stated as:

According to physician Robert Barouki (2023), research on women's health has historically been limited by social bias and an emphasis on male physiology. French geneticist Claudine Junien noted in 2016 that France lagged behind other countries in integrating sex-based biological differences in research and treatment, though attention to gender parity in healthcare was increasing.

Sources: en.wikipedia.org

Further detail

== Prognosis == As of March 2020, only 50 cases of CMRD have been documented in the medical literature. This small number speaks to the rarity of the disease as well as the lack of thorough research and documentation. As a result, the full course of the disease, life expectancy, and mortality are also poorly documented. Clinical manifestation of CMRD symptoms begin during infancy and early childhood but may go undetected due to the non-specific symptoms associated with the disease. Many of these symptoms can be attributed to malnutrition and nonspecific postnatal diarrhea, confounding early diagnosis. Careful regulation of diet and nutrition are required for management of CMRD since the disease results from the poor absorption of nutrients from food.

The station's exterior had become somewhat grimy, and due to its vast scale, the station was expensive to maintain. A renovation covered some of the grand columns with plastic and blocked off the spacious central hallway with a new ticket office. The Pennsylvania Railroad optioned the air rights, which called for the demolition of the head house and train shed, to be replaced by an office complex and a new sports complex, while the tracks of the station would remain untouched. Plans for the new Penn Plaza and Madison Square Garden were announced in 1962. In exchange for the air rights to Penn Station, the PRR would receive a smaller underground station at no cost and a 25 percent stake in the new Madison Square Garden Complex. Modern architects rushed to save the ornate building, but to no avail; demolition of the above-ground head house began in October 1963. A giant steel deck was placed over the tracks and platforms to allow rail service to continue during construction. Photographs of the day showed passengers waiting for trains even as the head house was demolished around them. This was possible because most of the rail infrastructure (including the waiting room, concourses, and boarding platforms) was below street level. The demolition of the Penn Station head house caused outrage internationally. "One entered the city like a god. One scuttles in now like a rat," the architectural historian Vincent Scully wrote after the removal of the original station.

== History == In 1929, Danish scientist Henrik Dam investigated the role of cholesterol by feeding chickens a cholesterol-depleted diet. He initially replicated experiments reported by scientists at the Ontario Agricultural College. McFarlane, Graham and Richardson, working on the chick feed program at OAC, used chloroform to remove all fat from chick chow. They noticed that chicks fed only fat-depleted chow developed hemorrhages and started bleeding from tag sites. Dam found that these defects could not be restored by adding purified cholesterol to the diet. It appeared that – together with the cholesterol – a second compound was extracted from the food, and this compound was called the coagulation vitamin. The new vitamin received the letter K because the initial discoveries were reported in a German journal, in which it was designated as Koagulationsvitamin. Edward Adelbert Doisy of Saint Louis University did much of the research that led to the discovery of the structure and chemical nature of vitamin K. Dam and Doisy shared the 1943 Nobel Prize for medicine for their work on vitamin K1 and K2 published in 1939. Several laboratories synthesized the compound(s) in 1939. For several decades, the vitamin K–deficient chick model was the only method of quantifying vitamin K in various foods: the chicks were made vitamin K–deficient and subsequently fed with known amounts of vitamin K–containing food. The extent to which blood coagulation was restored by the diet was taken as a measure for its vitamin K content.

=== Additives === The mechanical properties of hydrogels can be fine-tuned in many ways beginning with attention to their hydrophobic properties. Another method of modifying the strength or elasticity of hydrogels is to graft or surface coat them onto a stronger/stiffer support, or by making superporous hydrogel (SPH) composites, in which a cross-linkable matrix swelling additive is added. Other additives, such as nanoparticles and microparticles, have been shown to significantly modify the stiffness and gelation temperature of certain hydrogels used in biomedical applications.

In 1981, the company was founded by two scientist/engineers from Hewlett Packard, Sam Eletr and André Marion based on technology developed by Leroy Hood and Marvin H. Caruthers. In 1982, Applied Biosystems released its first commercial instrument, the Model 470A Protein Sequencer. The machine enabled scientists to determine the order of amino acids within a purified protein, which in turn correlated with the protein's function. With 40 employees, the company, reported first-time revenue of US$402,000. In 1983, the company was led by its president and Chairman of the Board, Sam Eletr and Chief Operating Officer Andre Marion, the company doubled its number of employees to 80, and its stock went public on the NASDAQ exchange under the symbol ABIO, with revenues of US$5.9 million. A new product was a fluorescent molecular tag for immunodiagnostic assays. The company released its second commercial instrument, the Model 380A DNA Synthesizer, which made oligonucleotides, short DNA strands, for polymerase chain reaction (PCR), DNA sequencing, and gene identification. The two sequencer and synthesizer products allowed molecular biologists to clone genes by building oligonucleotides with the desired protein's DNA sequence. Automated DNA sequencing began at the California Institute of Technology, using fluorescent dyes, with Rights to the technology granted to Applied Biosystems. At CIT, Dr. Leroy Hood and Dr. Lloyd Smith, together pioneered those first DNA sequencing machines.

Sources: en.wikipedia.org

Frequently asked questions

Is CJC-1295 a natural hormone?

No. It is a synthetic analogue modeled on the first 29 residues of human GHRH. The substitutions and any linker are laboratory modifications rather than features of the endogenous peptide.

Why do two versions share one name?

Early development used the albumin-binding form, and a shorter variant was later discussed under the same label. Because the two differ in half-life and handling, ambiguity arises whenever a source omits the variant designation.

What is the relationship to GRF(1-29)?

The compound derives from that fragment but is not identical to it. The parent fragment lacks the stabilizing substitutions, so its degradation rate and duration of action differ noticeably.

How long does the albumin-binding form remain active?

Reported values cluster in the range of several days, reflecting slow release from the albumin complex. Estimates differ across species and assay platforms. The figure describes circulation time in study settings rather than a fixed property.

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