A practical reference on GRF(1-29): what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-03-04 and is reviewed periodically as new material appears.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular weight (with DAC) | ~3647 Da | Calculated from the full amino acid sequence |
| Molecular weight (without DAC) | ~3368 Da | Mod GRF(1-29) variant |
| Appearance | White lyophilized powder | Typical form supplied for research |
| Solubility | Soluble in water | Dissolves in aqueous buffers |
| Receptor target | GHRH receptor | Expressed on pituitary somatotroph cells |
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.
Identity and purity are assessed mainly by reversed-phase high-performance liquid chromatography combined with mass spectrometry. The chromatographic separation resolves the target peptide from truncation products and from species carrying oxidised residues, while mass measurement confirms the expected molecular mass. Because the two common variants differ by roughly 280 daltons, a mass determination distinguishes them unambiguously. Purity is often quoted as a percentage of total peak area, although that figure depends on the detection wavelength and the integration method applied.
Reported half-lives differ widely between the two variants and between species. Values for the albumin-binding form are usually expressed in days, while the unconjugated form is measured in minutes to a few hours. Sampling schedules, assay sensitivity, and route of administration all influence the numbers, which limits direct comparison across studies. Whether sustained receptor occupancy produces different downstream effects from pulsatile stimulation remains an open question in the published work. Claims about relative potency should therefore be read alongside the specific study design that produced them.
Lyophilised powder is the usual supplied form. The material is hygroscopic, so vials are typically equilibrated to room temperature before opening in order to prevent condensation on the contents. Long-term storage is generally described at minus twenty degrees Celsius or colder, protected from light and moisture. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of soluble material. A reconstituted solution is considerably less stable than the dry powder and is normally kept refrigerated for short periods only.
In some organisms, notably birds, and ornithischian dinosaurs, portions of the tendon can become ossified. In this process, osteocytes infiltrate the tendon and lay down bone as they would in sesamoid bone such as the patella. In birds, tendon ossification primarily occurs in the hindlimb, while in ornithischian dinosaurs, ossified axial muscle tendons form a latticework along the neural and haemal spines on the tail, presumably for support.
==== Topical preparations ==== Cosmetics may contain a non-gelling variant of gelatin under the name hydrolyzed collagen (hydrolysate). Hydrolyzed collagen may be found in topical (applied to the skin) creams, acting as a product texture conditioner, and moisturizer.
=== Oxygen compounds === Three americium oxides are known, with the oxidation states +2 (AmO), +3 (Am2O3) and +4 (AmO2). Americium(II) oxide was prepared in minute amounts and has not been characterized in detail. Americium(III) oxide is a red-brown solid with a melting point of 2205 °C. Americium(IV) oxide is the main form of solid americium which is used in nearly all its applications. As most other actinide dioxides, it is a black solid with a cubic (fluorite) crystal structure. The oxalate of americium(III), vacuum dried at room temperature, has the chemical formula Am2(C2O4)3·7H2O. Upon heating in vacuum, it loses water at 240 °C and starts decomposing into AmO2 at 300 °C, the decomposition completes at about 470 °C. The initial oxalate dissolves in nitric acid with the maximum solubility of 0.25 g/L.
=== Lack of efficacy === A 2022 meta-analysis by Leichsenring and others found that the treatment effects of psychotherapies and psychiatric drugs (i.e. "pharmacotherapies") is "limited", in spite of "half a century of research, thousands of RCTs and millions of invested funds". A 2012 review of meta-analyses found that psychiatric medications are about as effective as those used in general medicine. However, a 2023 umbrella review found that studies of mental health outcomes most often use symptom remission as the outcome of interest (36.9%) and recovery the least often (2.5%); further, the systematic reviews were often found to be of critically low quality (67.5%), individual studies at high risk of bias (98.8%), and analysis studies at high risk bias (97.7%).
Sources: en.wikipedia.org
== Threats == It was overexploited in the twentieth century and was classed as a vulnerable species in 1998. This reached a level in the early twenty-first century where most trees of a size for commercial use had been cut down. As a consequence, other species of Dalbergia started to be exploited in its place.
Linus Carl Pauling was born on February 28, 1901, in Portland, Oregon, the firstborn child of Herman Henry William Pauling (1876–1910) and Lucy Isabelle "Belle" Darling (1881–1926). He was named "Linus Carl", in honor of Lucy's father, Linus, and Herman's father, Carl. His ancestry included German and English-Scottish. In 1902, after his sister Pauline was born, Pauling's parents decided to move out of Portland to find more affordable and spacious living quarters than their one-room apartment. Lucy stayed with her husband's parents in Lake Oswego until Herman brought the family to Salem, where he worked briefly as a traveling salesman for the Skidmore Drug Company. Within a year of Lucile's birth in 1904, Herman Pauling moved his family to Lake Oswego, Oregon where he opened his own drugstore. He moved his family to Condon, Oregon, in 1905. By 1906, Herman Pauling was suffering from recurrent abdominal pain. He died of a perforated ulcer on June 11, 1910, leaving Lucy to care for Linus, Lucile and Pauline. Pauling attributes his interest in becoming a chemist to being amazed by experiments conducted by a friend, Lloyd A. Jeffress, who had a small chemistry lab kit. He later wrote: "I was simply entranced by chemical phenomena, by the reactions in which substances, often with strikingly different properties, appear; and I hoped to learn more and more about this aspect of the world." In high school, Pauling conducted chemistry experiments by scavenging equipment and material from an abandoned steel plant.
=== Alcoholism === Alcoholism has been shown to produce sleep with less slow wave sleep and less delta power, while increasing stage 1 and REM incidence in both men and women. In long-term alcohol abuse, the influences of alcohol on sleep architecture and reductions in delta activity have been shown to persist even after long periods of abstinence.
Sources: en.wikipedia.org
=== EC 1.1.2 With a cytochrome as acceptor === EC 1.1.2.1: glycerolphosphate dehydrogenase. As the acceptor is now known, the enzyme has been transferred to EC 1.1.5.3, glycerol-3-phosphate dehydrogenase. EC 1.1.2.2: mannitol dehydrogenase (cytochrome) EC 1.1.2.3: L-lactate dehydrogenase (cytochrome) EC 1.1.2.4: D-lactate dehydrogenase (cytochrome) EC 1.1.2.5: D-lactate dehydrogenase (cytochrome c-553) EC 1.1.2.6: polyvinyl alcohol dehydrogenase (cytochrome) EC 1.1.2.7: methanol dehydrogenase (cytochrome c) EC 1.1.2.8: alcohol dehydrogenase (cytochrome c) EC 1.1.2.9: 1-butanol dehydrogenase (cytochrome c) EC 1.1.2.10: lanthanide-dependent methanol dehydrogenase EC 1.1.2.11: glucoside 3-dehydrogenase (cytochrome c)
Self-assembly is a scalable and parallel process which can involve large numbers of components in a short timeframe. Can result in structural dimensions across orders of magnitude, from nanoscale to macroscale. Is relatively inexpensive compared to the top-down assembly approach, which often consumes large amounts of finite resources. Natural processes that drive self-assembly tend to be highly reproducible. The existence of life is strongly dependent on the reproducibility of self-assembly. Challenges There exist several outstanding challenges in self-assembly, due to a variety of competing factors. Currently self-assembly is difficult to control on large scales, and to be widely applied we will need to ensure high degrees of reproducibility at these scales. The fundamental thermodynamic and kinetic mechanisms of self-assembly are poorly understood - the basic principles of atomistic and macroscale processes can be significantly different than those for nanostructures. Concepts related to thermal motion and capillary action influence equilibrium timescales and kinetic rates that are not well defined in self-assembling systems. Top-down vs bottom-up synthesis
Sorenson, MD, from the Mayo Clinic in Rochester, Minnesota "While this is very disappointing, at least it was definitive and gives, I think, a pretty definitive answer, at least for this strategy for this drug," Dr. Sorenson said. However, he added, "there is still a great deal of evidence that the IGF-1 pathway can be beneficial to people who have ALS, but just not the way we administered it." Novel methods of delivering IGF-1 in a more selected fashion are now under way, including the use of viral mediators or stem cells. Two previous phase 3 trials of IGF-1 in ALS showed inconsistent results: 1 trial, carried out in North America, did find a benefit, whereas the other, a European trial, did not confirm the earlier findings. "The results of our study most resemble those of the previous European study, with no benefit in either survival or functional scales", De Sorenson concludes. "It is disappointing that we were unable to confirm the benefit that was noted in the previous North American study." Conclusive evidence points, what Iplex (and any form of IGF-1) can't slow progression in human ALS. Lot of sites that have published articles about the link between Lyme disease and ALS are sponsored by clinics specializing in the treatment of chronic Lyme disease, or by the sellers of products for treating this, or both.
== Further reading == Budd, A. (2012). "Introduction to Genome Biology: Features, Processes, and Structures". Evolutionary Genomics. Methods in Molecular Biology. Vol. 855. pp. 3–4. doi:10.1007/978-1-61779-582-4_1. ISBN 978-1-61779-581-7. PMID 22407704.
Sources: en.wikipedia.org
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.
The maleimide group forms a covalent link with albumin, an abundant blood protein. This attachment slows clearance, so a single administration persists much longer than the unmodified peptide. The feature is the main reason the two variants are handled differently in study design.
It is not an approved therapeutic product in major regulatory jurisdictions. It appears in research chemical catalogs and scientific literature rather than pharmacy shelves. Clinical development was limited and did not reach approval.
The names are often used interchangeably in casual writing, but they are not strictly identical. Modified GRF(1-29) refers to the unconjugated analogue carrying only the four substitutions. The version sold as CJC-1295 with DAC includes the albumin binding linker and clears much more slowly.