Everything below concerns Mod GRF(1-29). We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-05-04. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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 peptide designed to mimic growth hormone-releasing hormone (GHRH), the endogenous signal that prompts the pituitary gland to release growth hormone. The compound is a modified fragment of the natural hormone, spanning the first twenty-nine amino acids of GHRH with several substitutions that slow enzymatic breakdown. Two variants circulate in research settings: one carrying a drug affinity complex (DAC) and one without it. The DAC-free form is frequently labelled Mod GRF(1-29) in catalogs and discussion forums.
The peptide binds GHRH receptors on somatotroph cells within the anterior pituitary, triggering a signalling cascade that increases growth hormone secretion. Its improved resistance to dipeptidyl peptidase IV degradation distinguishes it from the parent hormone. In the DAC-bearing version, a maleimide group reacts with a cysteine residue on serum albumin, forming a covalent bond that keeps the peptide in circulation far longer. That albumin attachment is the central design feature separating the two research variants.
Pharmacokinetic behaviour differs sharply between the two forms. The DAC-bearing peptide shows an extended circulation time measured in days, whereas the version without the complex is cleared within roughly half an hour. This gap shapes how researchers design dosing schedules in animal models. Whether the prolonged presence of the DAC form produces effects meaningfully different from the short-acting variant remains an open question, since comparative human data are scarce.
| Property | Value | Notes |
|---|---|---|
| Physical form | Lyophilized white powder | Supplied as a freeze-dried solid for research use |
| Molecular weight | Approximately 3,647 Da (DAC form) | Lower for the variant lacking the albumin-binding moiety |
| Solubility | Soluble in water and aqueous buffer | Typically dissolved in sterile or bacteriostatic water |
| Typical storage temperature | −20 °C or below | Dry powder, desiccated and protected from light |
| Common analytical method | Reversed-phase HPLC with mass spectrometry | Used for purity estimation and identity confirmation |
The distinguishing feature of the DAC form is a maleimide-containing group that reacts with the free thiol of cysteine-34 on human serum albumin. This reaction forms a covalent bond without enzymatic assistance, and it takes place after the peptide enters the bloodstream. Because albumin is abundant and long-lived, the attached peptide is carried through circulation far longer than an unmodified fragment would survive. The chemistry is a deliberate pharmacokinetic strategy rather than a change to receptor activity.
Enzymatic protection is a separate mechanism from plasma protein binding. The four substitutions in the backbone reduce recognition by dipeptidyl peptidase IV, which normally cleaves the natural hormone within minutes. Without the reactive group, this resistance still yields only a short window of activity, generally reported in the range of tens of minutes. With it, reported half-lives in early human work extended to several days. The size of that gap is the main practical distinction between the two materials.
CJC-1295 is the name used for a synthetic peptide modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound was described by a Canadian drug discovery company in the mid-2000s as a long-acting research tool. Two closely related molecules share the name in practice: one carries a drug affinity complex, or DAC, group, and one does not. The distinction matters because the two behave differently in circulation.
The peptide backbone corresponds to GRF(1-29), the first 29 residues of native growth hormone-releasing hormone, which retains most of the receptor-activating activity of the full-length molecule. Four substitutions distinguish the analog from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes slow cleavage by dipeptidyl peptidase IV, the enzyme that degrades native hormone in plasma within minutes. The outcome is improved enzymatic stability combined with a still brief residence time when no additional modification is present.
Colin Pitchfork was arrested in 1987 and it was found that his DNA profile matched the semen samples from the murder. Because of this case, DNA databases were developed. There is the national (FBI) and international databases as well as the European countries (ENFSI: European Network of Forensic Science Institutes). These searchable databases are used to match crime scene DNA profiles to those already in a database.
=== 1990s: Xatrix Entertainment === Antonov's first job in the gaming industry was as a painter of the maps found in Xatrix Entertainment's 1997 PC FPS Redneck Rampage. He then worked on three more Xatrix titles for the PC that came out the year after: Redneck Deer Huntin' and Redneck Rampage Rides Again, sequels to the 1997 game; and Quake II Mission Pack: The Reckoning, an expansion pack for the 1997 FPS Quake II. Antonov followed these by working as a level designer for the 1999 PC FPS Kingpin: Life of Crime, which has an art deco aesthetic. The game takes place in a major city, so before its levels were designed, he explored L.A. to get an understanding of city layouts. He later claimed Kingpin's game world was "the first realistic city" created in the Quake II game engine. That someone could be employed by a major game studio as both an artist and level designer, Antonov said, was because "at this time, the video game industry did not have clearly define[d] positions, and an artist could create entire worlds".
=== Source attribution and forensics === Stable isotope ratios have found uses in various instances where the authenticity or origin of a chemical compound is called into question. Such situations include assessing the authenticity of food, wine and natural flavors; drug screening in sports (see doping in sport); pharmaceuticals; illicit drugs; and even helping identify human remains. In these cases it is often not enough to detect or quantify a certain compound, since the question is the origin of the compound. The strength of hydrogen isotope analysis in answering these questions is that the DHR of a natural product is often related to the natural water DHRs in the area where the product was formed (see: Hydrologic cycle). Since DHRs vary significantly between different areas, this can be a powerful tool in locating the original source of many different substance.
Sources: en.wikipedia.org
=== Amphibian === The unfertilized oocyte of a frog, or Xenopus laevis, has also been utilized as an expression system for heterologous expression. Initially used to express the acetylcholine receptor in 1982, since then it has been used for a variety of reasons. These oocytes are produced by frogs year round and thus are relatively abundant, and translation occurs with high fidelity. Of the many limitations to the oocyte system, one major one is that the produced heterologous proteins interact with the frog oocyte's proteins which changes its behavior compared to what it would be in a mammalian cell. Additionally, where mammals are diploid, these xenopus have four homologous copies of each chromosome and thus, proteins derived may have a different function. More research is needed to examine the protein production of X. laevis systems.
== Murders and assaults == While she was a nurse at Caressant Care, Wettlaufer began injecting some of the patients she cared for with insulin. In some cases, the amount was not enough to kill the patient; she was charged with, and confessed to, aggravated assault or attempted murder for those cases. Wettlaufer's first assaults occurred sometime between June 25 and December 31, 2007. She confessed that she injected sisters Clotilde Adriano (age 87) and Albina Demedeiros (88) with insulin. While they later died, their deaths were not attributed to Wettlaufer. She confessed to two counts of aggravated assault. The first case in which Wettlaufer injected a patient with enough insulin to directly cause death was on August 11, 2007, when she murdered James Silcox (84), a World War II veteran and father of six. From 2007 to March 2014, Wettlaufer also murdered the following patients at Caressant Care:
=== EC 1.18.1 With NAD+ or NADP+ as acceptor === EC 1.18.1.1: rubredoxin—NAD+ reductase EC 1.18.1.2: ferredoxin—NADP+ reductase EC 1.18.1.3: ferredoxin—NAD+ reductase EC 1.18.1.4: rubredoxin—NAD(P)+ reductase EC 1.18.1.5: Putidaredoxin—NAD+ reductase EC 1.18.1.6: adrenodoxin-NADP+ reductase EC 1.18.1.7: ferredoxin—NAD(P)+ reductase (naphthalene dioxygenase ferredoxin-specific) EC 1.18.1.8: Now EC 7.2.1.2, ferredoxin—NAD+ oxidoreductase (Na+-transporting)
Sources: en.wikipedia.org
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.
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.
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.
The synthetic peptide keeps the receptor-binding region of GHRH but carries substitutions that resist enzymatic cleavage. In the DAC version, an added group also anchors the molecule to albumin, extending its presence in the bloodstream.