DAC comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-10-12. Numbers and descriptions here follow the published literature rather than marketing material.
Reports on this compound commonly follow serum growth hormone and insulin-like growth factor 1 across defined time windows. Protocols differ in sampling frequency, assay platform, and participant characteristics, which makes direct comparison between publications difficult. Some work focuses on pulsatile release patterns instead of average concentrations. Whether repeated exposure alters endogenous hormone rhythms over long periods remains an open question, and the formal literature is thinner than the volume of informal commentary implies.
Once in circulation, the peptide binds the growth hormone-releasing hormone receptor displayed on pituitary somatotroph cells. Receptor activation couples to Gs proteins, elevates intracellular cyclic AMP, and drives protein kinase A signaling inside the cell. That cascade increases discharge of growth hormone into the bloodstream. The analog therefore operates through a receptor pathway that already exists for the body's own releasing hormone, rather than through an engineered artificial target.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Primary target | GHRH receptor | Present on pituitary somatotroph cells |
| Signal pathway | Gs, cyclic AMP, protein kinase A | Sequence follows receptor activation |
| Main measured effect | Growth hormone release | Insulin-like growth factor 1 shifts indirectly |
| Half-life, binding form | Several days | Extended through serum albumin association |
| Half-life, unmodified form | About 30 minutes | Limited mainly by enzymatic cleavage |
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.
The peptide backbone includes a D-alanine at position two, which resists cleavage by dipeptidyl peptidase IV, and several other substitutions that reduce degradation. Its molecular weight is roughly 3.4 kDa without the linker and about 3.6 kDa with it. The molecule is water soluble and is normally supplied as a lyophilized powder. Precise sequence and mass values depend on which variant is described, so technical documents usually state the exact form being referenced.
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.
Lyophilized material is typically stored at minus twenty degrees Celsius or lower. Keeping the vial dry and protected from light preserves peptide integrity. Repeated freeze-thaw cycles can cause aggregation or loss of activity. Once dissolved, solutions are generally kept at two to eight degrees Celsius. Stability data for reconstituted solutions vary, and long-term behavior is not fully established. Working aliquots reduce the number of times a stock container is opened.
Reverse-phase high-performance liquid chromatography is the standard tool for purity assessment. The technique separates the target peptide from truncated or modified byproducts. Mass spectrometry confirms molecular weight and supports sequence verification. Electrospray ionization and matrix-assisted laser desorption are both used. Amino acid analysis provides an independent check on composition. Purity values are commonly reported as area percentage from the chromatogram. Residual trifluoroacetate and water content are also measured in many quality programs.
Two principal forms appear in the literature and in research supply. One carries a drug affinity complex, a maleimide-based group that forms a covalent bond with circulating albumin. This linkage slows clearance and produces a long-lasting elevation of peptide levels. The other form lacks that group and is often labeled MOD GRF(1-29). It has a much shorter circulation time. Both variants retain the same core receptor-binding sequence. Reported half-lives differ substantially between the two.
At the pituitary, the peptide binds the growth hormone-releasing hormone receptor on somatotroph cells. Receptor activation raises intracellular cyclic AMP and triggers release of stored growth hormone. Somatostatin and other hypothalamic signals modulate this response. Negative feedback from insulin-like growth factor 1 also influences output. The same regulatory architecture operates with the native hormone. Whether the synthetic analog alters feedback dynamics over repeated exposure remains an open question. Most published receptor work uses cell models rather than intact human systems.
CJC-1295 is a synthetic peptide belonging to the growth hormone-releasing hormone analog family. It comprises twenty-nine amino acid residues derived from the N-terminal region of natural GHRH. The molecule incorporates several non-natural substitutions that increase resistance to enzymatic degradation. These modifications extend its activity compared with the native hormone fragment. Researchers use it to study pituitary growth hormone secretion in laboratory and clinical settings. This compound is distinct from native GHRH in its stability profile.
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.
Identity and purity are established with reversed phase high performance liquid chromatography coupled to mass spectrometry. The chromatographic step separates the target peptide from truncated sequences and deletion products, while the mass measurement confirms the expected molecular weight to within a fraction of a dalton. Because the two common variants differ by the presence of the linker, mass alone can distinguish them in the unconjugated state. Amino acid analysis and peptide mapping are used when sequence level confirmation is required.
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.
== External links == Roda, A. (2005). "Toward Multianalyte Immunoassays: A Flow-Assisted, Solid-Phase Format with Chemiluminescence Detection". Clinical Chemistry. 51 (10): 1993–1995. doi:10.1373/clinchem.2005.053108. ISSN 0009-9147. PMID 16299900.
Werner discovered the spatial arrangements of the ligands that were involved in the formation of the complex hexacoordinate cobalt. His theory allows one to understand the difference between a coordinated ligand and a charge balancing ion in a compound, for example the chloride ion in the cobaltammine chlorides and to explain many of the previously inexplicable isomers. In 1911, Werner first resolved the cobalt/ammonia coordination complex hexol into optical isomers, overthrowing the theory that only carbon compounds could possess chirality.
== Research == Biggar's research includes many different areas from different fields within molecular biology, biochemistry, and physical biochemistry. His main areas of research interest are Oxidative Cell Stress, Functional Proteomics, Bioinformatics, and Molecular Pharmacology. He is particularly known for his research in the new field of Non-histone Lysine Methylation and its relation to both functional proteomics and cell stress.
== Research == Muscimol has been clinically studied for a number of potential medical uses. It was assessed in small clinical studies in the treatment of Huntington's disease, tardive dyskinesia, and schizophrenia in the 1970s but was not found to be useful for these indications. Another study evaluated muscimol in schizophrenics with tardive dyskinesia in 1992. Studies also assessed the biochemical effects of muscimol in humans in the late 1970s and early 1980s. According to Povl Krogsgaard-Larsen, muscimol was too toxic and non-selective and as such was not developed for use as a pharmaceutical drug. Instead, the synthetic analogue gaboxadol (THIP), which was more selective and much less toxic, was developed. In 2019, a phase 1 clinical trial of muscimol for drug-resistant epilepsy was published. It has also been formally investigated for potential treatment of Alzheimer's disease and Parkinson's disease. A 2023 systematic review and meta-analysis of 22 preclinical studies found that muscimol reduces neuropathic pain in animals, with effects beginning within 15 minutes and lasting up to 3 hours. Muscimol has never been approved as a pharmaceutical drug for any use anywhere in the world.
=== 23 March === Dmitry Medvedev, former president of Russia and current deputy chairman of Russia's security council, threatened war against any country, if their officials attempted to arrest Putin on the ICC warrant, during a future state visit. He also described the ICC as a "legal nonentity that had never done anything significant". He also threatened that Russia would in that case possibly attack the International Criminal Court with hypersonic missiles that would be launched from a ship in the North Sea. Medvedev also reaffirmed his previous warnings that the chance of nuclear war increases each time the western nations send military aid to Ukraine. Sweden approved 6.2 billion kronor worth of military aid to Ukraine which included vehicles and ammunition.
Sources: en.wikipedia.org
=== Musculoskeletal === Evidence does not support a benefit in delayed-onset muscle soreness. It may be useful for muscle pain and injuries. A 2008 Cochrane Library review concluded that LLLT has insufficient evidence for treatment of nonspecific low back pain, a finding echoed in a 2010 review of chronic low back pain. A 2015 review found benefit in nonspecific chronic low-back pain. LLLT may be useful in the treatment of both acute and chronic neck pain. In 2013, however, a systematic review and meta-analysis of LLLT for neck pain indicated that the benefit was not of significant importance and that the evidence had a high risk of bias. In a study testing the efficacy of low-level laser therapy treating plantar fasciitis found that LLLT significantly reduces pain in lower extremity tendinopathy and plantar fasciitis in the short and medium terms. The same study also stated that while comparing the effect of LLLT to that of therapeutic ultrasound in persons with patellar tendinopathy, and they found a statistically significant effect in favor of LLLT, both on pain reduction and function. There are tentative data that LLLT is useful in the short-term treatment of pain caused by rheumatoid arthritis, and possibly chronic joint disorders. Research that compared the effects of LLLT against other treatments, sham treatments, or no treatment at all, and randomized adult patients with rheumatoid arthritis to receive it were considered.
The side effects of elagolix are in general similar to menopausal symptoms. The most common side effects of elagolix (incidence ≥10%) are hot flashes, night sweats, headaches, nausea, and amenorrhea (cessation of menstruation). The next most frequent side effects of elagolix (incidence ≥5%) are insomnia, anxiety, arthralgia (joint pain), depression, and mood changes. Less common side effects of elagolix (incidence ≥3% and <5%) include decreased sex drive, diarrhea, abdominal pain, weight gain, dizziness, constipation, and irritability. Other common side effects of elagolix include decreased bone mineral density (BMD) and changes in the blood lipid profile. Rare but serious adverse effects that were observed during elagolix therapy in clinical trials included appendicitis (0.3%), abdominal pain (0.2%), and back pain (0.2%), though it is unknown if these were due to elagolix. Other serious adverse effects of elagolix may include bone loss, miscarriage, suicidality, and elevated liver enzymes. Elagolix was discontinued due to side effects by 5 to 10% of women in clinical trials, with the most common reasons being hot flashes or night sweats, nausea, and decreased BMD. Elagolix dose- and duration-dependently decreases BMD in premenopausal women with long-term therapy. After 6 months of treatment with elagolix, lumbar spine BMD was decreased by 0.3 to 1.3% with 150 mg once per day and by 2.5 to 3.1% with 200 mg twice per day.
=== Combination ESG and pharmacologic therapy === ESG can safely be combined with weight loss medications to improve weight loss or prevent weight regain after the procedure. The daily injectable medication liraglutide showed greater total body weight loss when combined with ESG compared to ESG alone at 7 months (approximately 25% vs 20% respectively). Similar results are anticipated with other incretin agents, such as semaglutide and tirzepatide, though no studies have directly assessed these combinations.
In March 1916 (BR.23–BR.26), Robertson announced the results of a series of experiments that he and his assistant, Louis Adolph Ray, had conducted with the white mice — chosen as his "experimental animal" because of their "hardiness, rapid growth, smallness, and fecundity" (BR.23, p.366) — wherein the oral administration of tethelin, a "growth-controlling principle" (which they later described as "the ether-precipitable fraction of an alcoholic extract of the anterior lobe of the pituitary body"), produced precisely "the same effects on their growth" as those "which [had] accompan[ied] the [oral] administration of the whole tissue of the anterior lobe of the pituitary body" to his control group (BR.25, p.397). As Everitt (AE.2, p.63) notes — having distinguished (p.66) Robertson and Ray's "growth controlling principle" of the pituitary (BR.35) from Moon, et al.'s "growth stimulating principle" (HM.2) — it was not until the (1921) work of Herbert Evans and Joseph Long (HE.1; HE.2) that "[it was] conclusively proved that the pituitary contained a growth-stimulating hormone". Evans and Long also discovered that, whilst the oral administration of their "pituitary principle" had no effect, administration per medium of an intraperitoneal injection was effective: which led them to the conclusion that whatever the pituitary's 'active principle' might be, it was "digested in the alimentary canal".
Sources: en.wikipedia.org
It acts on the growth hormone-releasing hormone receptor found on pituitary somatotroph cells. Activation of that receptor triggers growth hormone release through a cyclic AMP dependent pathway.
It links the peptide to serum albumin after administration, which delays removal from circulation. Reported half-life shifts from roughly half an hour to several days as a result.
Most published work tracks serum growth hormone and insulin-like growth factor 1 over time. Sampling schedules and assay methods vary enough that figures are not directly comparable across reports.
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.