If you have been reading about GHRH analogue and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-12-26. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Both forms act at the pituitary receptor for growth hormone-releasing hormone and increase growth hormone output, which in turn raises insulin-like growth factor 1. A long-acting analog produces sustained rather than pulsatile stimulation, and the physiological consequences of that pattern are not fully settled. Published human data on the extended form remain limited, and much of what circulates in discussion traces to early company reports rather than independent replication. How sustained exposure affects normal feedback remains an open question.
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.
CJC-1295 is a synthetic peptide analog of growth hormone-releasing hormone, constructed on the 29-amino-acid fragment designated GRF(1-29). The name began as an internal development code during the 1990s and later spread through research supply catalogs and discussion forums. The molecule does not occur in nature; its sequence is engineered rather than isolated from tissue. Two related compounds are sold under this single label, and they differ by one appended chemical group that strongly influences how long the peptide remains in circulation.
The dividing feature between the two forms is a maleimide-based drug affinity complex, abbreviated DAC. In the DAC-bearing version, a linker attaches the peptide to serum albumin after administration, and that association slows removal from plasma. The version lacking DAC appears in catalogs as MOD GRF(1-29) or tetrasubstituted GRF(1-29). Because informal writing treats both as one item, comparisons drawn from such sources routinely blend measurements taken from two molecules with substantially different behavior.
Four amino acid substitutions separate the modified backbone from the parent GRF(1-29) sequence. These changes reduce recognition by dipeptidyl peptidase IV and related proteases, extending the interval before degradation. Development work in this area sought longer-acting GHRH analogs for endocrine investigation. Published descriptions treat the substitution set as a defining property of the core sequence, while the albumin-binding linker is described separately as an optional addition to that same backbone.
| Property | Value | Notes |
|---|---|---|
| Duration with linker | Several days | Reported in early human work |
| Duration without linker | Tens of minutes | Short plasma residence |
| Albumin attachment site | Cysteine-34 | Covalent maleimide reaction |
| Primary receptor | Pituitary GHRH receptor | Stimulates growth hormone release |
| Downstream marker | Insulin-like growth factor 1 | Indirect measure of activity |
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.
The compound emerged from work at a Canadian biotechnology firm in the early 2000s. Early human studies examined its effect on growth hormone and insulin-like growth factor 1 in healthy volunteers and in people with HIV-associated fat redistribution. Reports described sustained increases in both markers after a single injection. Development did not advance to regulatory approval, and the clinical programme was later discontinued. The molecule is now encountered mainly as a research chemical rather than a marketed medicine.
Two forms circulate in research settings and are frequently confused. One carries the drug affinity complex and is often written as CJC-1295 with DAC; the other lacks that group and is usually called modified GRF(1-29). The two share the same core sequence but differ sharply in how long they persist in blood. Products labelled only as CJC-1295 normally refer to the version carrying the complex. Documentation that omits the distinction leaves the intended molecule ambiguous.
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.
The second form adds a maleimide-bearing linker to the lysine at the carboxyl end. This group reacts with cysteine-34 on circulating serum albumin, forming a covalent bond that keeps the peptide in the bloodstream for far longer. ConjuChem developed the molecule as a way to extend the action of a peptide without frequent administration. The albumin attachment is the defining structural feature of the drug affinity complex version. Whether continuous exposure produces effects distinct from shorter pulses remains an unresolved research question.
However, only Lockyer proposed that the line was due to a new element, which he named after the Sun. The formal discovery of the element was made in 1895 by chemists Sir William Ramsay, Per Teodor Cleve, and Nils Abraham Langlet, who found helium emanating from the uranium ore cleveite, which is no longer regarded as a separate mineral species, but as a variety of uraninite. In 1903, large reserves of helium were found in natural gas fields in parts of the United States, by far the largest supplier of the gas. Liquid helium is used in cryogenics (its largest single use, consuming about a quarter of production), and in the cooling of superconducting magnets, with its main commercial application in MRI scanners. Helium's other industrial uses—as a pressurizing and purge gas, as a protective atmosphere for arc welding, and in processes such as growing crystals to make silicon wafers—account for half of the gas produced. A small but well-known use is as a lifting gas in balloons and airships. As with any gas whose density differs from that of air, inhaling a small volume of helium temporarily changes the timbre and quality of the human voice. In scientific research, the behavior of the two fluid phases of helium-4 (helium I and helium II) is important to researchers studying quantum mechanics (in particular the property of superfluidity) and to those looking at the phenomena, such as superconductivity, produced in matter near absolute zero. On Earth, it is relatively rare—5.2 ppm by volume in the atmosphere.
==== Commercialization ==== The company announced in November 2021 that it aims to achieve mass-manufacturing in 2024 of its silicon batteries, having pouch-cell samples produced by its manufacturing partner EVE Energy sent to be tested by global car makers. The company announced in 2023 that its batteries will be commercially available in VinFast vehicles in 2025. The CEO said that the company does not plan to become a battery manufacturer or supplier, but instead plans to license its technology to major manufacturers or lease dedicated manufacturing capacity from existing suppliers, saying its silicon batteries can be manufactured using existing factories and manufacturing processes. StoreDot demonstrated its batteries in a prototype Polestar 5 sedan in 2024, however the 2025 model was not set to debut with StoreDot batteries but with batteries developed and manufactured by SK On. StoreDot batteries were still in the testing phase in October 2024 and they had not been incorporated into any upcoming vehicle platforms. StoreDot stated in 2026 it needs two more years of development in order to commercialize its product.
Starmer says he has taken account of whether it would be right "to impose a further burden on the taxpayer". MSPs vote unanimously in favour of plans to ban dual mandates. Following an external review into the use of messaging services, Scotland's Deputy First Minister, Kate Forbes announces that Scottish Government ministers and staff will be banned from using WhatsApp for official business. Former First Minister of Scotland Humza Yousaf announces he will step down as an MSP at the 2026 Scottish Parliament election. Democracy and Boundary Commission Cymru unveils the names of the 16 constituencies that will make up the enlarged Senedd from 2026, with all but four of them known by exclusively Welsh language names. The Welsh Conservatives reaffirm their commitment to devolution following a social media post by MS Joel James, who said he wanted to get "rid" of the Senedd; the post, in response to the announcement of the constituencies for the 2026 election, was swiftly deleted. Nigel Farage says that Reform UK are in "open negotiations" with US billionaire Elon Musk about him donating to the party after the pair met at Donald Trump's Mar-a-Lago estate in Florida. 18 December – Reform UK confirms that Craig Campbell, a party official in Scotland, has been removed from his post after revelations his family has links to Ulster Loyalists and has a relatives who was convicted of murdering a Celtic fan. Police are called to what is described as a heated meeting of Oldham Council.
Sources: en.wikipedia.org
== Extensions == FASTQ format is a form of FASTA format extended to indicate information related to sequencing. It is created by the Sanger Centre in Cambridge. A2M/A3M are a family of FASTA-derived formats used for sequence alignments. In A2M/A3M sequences, lowercase characters are taken to mean insertions, which are then indicated in the other sequences as the dot (".") character. The dots can be discarded for compactness without loss of information. As with typical FASTA files used in alignments, the gap ("-") is taken to mean exactly one position. A3M is similar to A2M, with the added rule that gaps aligned to insertions can too be discarded.
=== 2006–2010 === On November 2, 2006, NHK demonstrated a live relay of a UHDTV program over a 260 kilometer distance by a fiber-optic network. Using dense wavelength division multiplex (DWDM), 24 Gbit/s speed was achieved with a total of 16 different wavelength signals. On December 31, 2006, NHK demonstrated a live relay of their annual Kōhaku Uta Gassen over IP from Tokyo to a 450 inches (11 m) screen in Osaka. Using a codec developed by NHK, the video was compressed from 24 Gbit/s to 180–600 Mbit/s and the audio was compressed from 28 Mbit/s to 7–28 Mbit/s. Uncompressed, a 20-minute broadcast would require roughly 4 TB of storage. The SMPTE first released Standard 2036 for UHDTV in 2007. UHDTV was defined as having two levels, called UHDTV1 (3840 × 2160) and UHDTV2 (7680 × 4320). In May 2007, the NHK did an indoor demonstration at the NHK Open House in which a UHDTV signal (7680 × 4320 at 60 fps) was compressed to a 250 Mbit/s MPEG2 stream. The signal was input to a 300 MHz wide band modulator and broadcast using a 500 MHz QPSK modulation. This "on the air" transmission had a very limited range (less than 2 meters), but shows the feasibility of a satellite transmission in the 36,000 km orbit. In 2008, Aptina Imaging announced the introduction of a new CMOS image sensor specifically designed for the NHK UHDTV project. During IBC 2008 Japan's NHK, Italy's RAI, BSkyB, Sony, Samsung, Panasonic Corporation, Sharp Corporation, and Toshiba (with various partners) demonstrated the first ever public live transmission of UHDTV, from London to the conference site in Amsterdam.
=== Class II === Class II hydrophobins have overall a more conserved amino acid sequence between the different types and, contrary to class I, they have short, regular inter-cysteine spacing. Opposite to class I, the class II hydrophobins monolayer formed at hydrophobic:hydrophilic interfaces is not fibrillar and it is not associated with formation of amyloid-structures, nor with large conformational changes. Nonetheless, high resolution atomic-force microscopy studies revealed the formation of a notable hexagonal repeating pattern over surfaces coated with the class II hydrophobin HBFI, meaning that these proteins are also able to form an ordered network in surface films. The crystal structures or HFBI and HFBII from Trichoderma reesei were the first class II hydrophobins to be determined.
Sources: en.wikipedia.org
A maleimide moiety reacts with the thiol of cysteine-34, forming a covalent bond. The reaction occurs in circulation without enzymatic catalysis.
The group is intended to alter distribution and persistence, not receptor engagement. The peptide portion still binds the pituitary receptor, so the primary difference is duration rather than potency.
Not firmly. Early reports describe several days for the extended form, but independent confirmations are sparse, and values vary with assay method and study design.
No. It is a laboratory-synthesized analog built on a fragment of the natural hormone. The natural peptide is shorter-lived and lacks the stabilizing substitutions found in the synthetic version.