GHRH analogue raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-06-08. Anything still debated is marked as such rather than presented as settled.
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.
CJC-1295 belongs to a family of synthetic peptides modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound is built from the first twenty-nine amino acids of the natural human sequence, a fragment that retains full receptor binding capacity. Native growth hormone-releasing hormone is degraded quickly in circulation, so the fragment alone has limited practical value. Early work therefore focused on chemical modifications that preserve receptor binding while slowing enzymatic breakdown. The result is a molecule described in the literature as a long-acting analog of the natural hormone.
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.
| 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 |
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.
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.
For example, the rare isotope carbon-14 was added to a particular tree and later detected in nearby plants and seedlings. One study observed a bidirectional carbon transfer between Betula papyrifera and Pseudotsuga menziesii, primarily through the hyphae of the ectomycorrhiza. However, not all plants are compatible with all fungal networks, so not all plants can exploit the benefits of established ectomycorrhizal linkages. The shared nutrient connection through CMNs has been suggested to be involved with other ecological processes such as seedling establishment, forest succession and other plant-plant interactions. Some arbuscular mycorrhizas have been shown to carry signals warning plants on the network of attack by insects or disease.
=== Controversy === The game faced scrutiny in Germany after being linked to the Erfurt school massacre in 2002 after it was found on the computer of the perpetrator, Robert Steinhäuser. Politicians, including Günther Beckstein, and media outlets, particularly Bild, then regularly referred to the game as Killerspiel 'killer game'. Calls for banning violent video games intensified, with politicians like Beckstein advocating for penalties against players. Media outlets like Frontal 21 on ZDF often portrayed players negatively. In 2002, Germany's BPjM considered indexing Counter-Strike but ultimately rejected it, concluding that the game's objectives could be achieved without violence and that its communication aspects were beneficial. Chancellor Gerhard Schröder criticized the decision as irresponsible. A Brazilian federal judge, Carlos Alberto Simões de Tomaz, ordered a ban on the sale of Counter-Strike and EverQuest in October 2007 arguing that the games "bring imminent stimulus to the subversion of the social order, attempting against the democratic state and the law and against public security". The order began to be enforced on January 17, 2008, but regional federal court order lifting the prohibition on the sale of Counter-Strike was published on June 18, 2009.
== Puberty onset == Puberty is preceded by adrenarche, marking an increase of adrenal androgen production between ages 6–10. Adrenarche is sometimes accompanied by the early appearance of axillary and pubic hair. The first androgenic hair resulting from adrenarche can be also transient and disappear before the onset of true puberty. The onset of puberty is associated with high GnRH pulsing, which precedes the rise in sex hormones, LH and FSH. Exogenous GnRH pulses cause the onset of puberty. Brain tumors which increase GnRH output may also lead to premature puberty. The cause of the GnRH rise is unknown. Leptin might be the cause of the GnRH rise. Leptin has receptors in the hypothalamus which synthesizes GnRH. Individuals who are deficient in leptin fail to initiate puberty. The levels of leptin increase with the onset of puberty, and then decline to adult levels when puberty is completed. The rise in GnRH might also be caused by genetics. A study discovered that a mutation in genes encoding both neurokinin B as well as the neurokinin B receptor can alter the timing of puberty. The researchers hypothesized that neurokinin B might play a role in regulating the secretion of kisspeptin, a compound responsible for triggering direct release of GnRH as well as indirect release of LH and FSH.
Infectious disease, e.g., COVID-19, dengue, Ebola, gastroenteritis, HIV, influenza, Lyme disease, rocky mountain spotted fever, secondary syphilis, malaria, mononucleosis, as well as infections of the skin, e.g., abscesses and boils. Immunological diseases, e.g., relapsing polychondritis, autoimmune hepatitis, granulomatosis with polyangiitis, Horton disease, inflammatory bowel diseases, Kawasaki disease, lupus erythematosus, sarcoidosis, Still's disease, rheumatoid arthritis, lymphoproliferative disorders and psoriasis; Tissue destruction, as a result of cerebral bleeding, crush syndrome, hemolysis, infarction, rhabdomyolysis, surgery, etc.; Cancers, particularly blood cancers such as leukemia and lymphomas; Metabolic disorders, e.g., gout, and porphyria; Inherited metabolic disorder, e.g., Fabry disease. Adult and pediatric manifestations for the same disease may differ; for instance, in COVID-19, one metastudy describes 92.8% of adults versus 43.9% of children presenting with fever. In addition, fever can result from a reaction to an incompatible blood product.
Sources: en.wikipedia.org
Diisopropylfluorophosphate (DFP) is an example of an irreversible protease inhibitor (see the "DFP reaction" diagram). The enzyme hydrolyses the phosphorus–fluorine bond, but the phosphate residue remains bound to the serine in the active site, deactivating it. Similarly, DFP also reacts with the active site of acetylcholine esterase in the synapses of neurons, and consequently is a potent neurotoxin, with a lethal dose of less than 100 mg. Suicide inhibition is an unusual type of irreversible inhibition where the enzyme converts the inhibitor into a reactive form in its active site. An example is the inhibitor of polyamine biosynthesis, α-difluoromethylornithine (DFMO), which is an analogue of the amino acid ornithine, and is used to treat African trypanosomiasis (sleeping sickness). Ornithine decarboxylase can catalyse the decarboxylation of DFMO instead of ornithine (see the "DFMO inhibitor mechanism" diagram). However, this decarboxylation reaction is followed by the elimination of a fluorine atom, which converts this catalytic intermediate into a conjugated imine, a highly electrophilic species. This reactive form of DFMO then reacts with either a cysteine or lysine residue in the active site to irreversibly inactivate the enzyme. Since irreversible inhibition often involves the initial formation of a non-covalent enzyme inhibitor (EI) complex, it is sometimes possible for an inhibitor to bind to an enzyme in more than one way.
=== Head and neck cancer === Tobacco smoking is the main risk factor for head and neck cancer. Cigarette smokers have a lifetime increased risk for head and neck cancer that is 5 to 25 times higher than the general population. The person who used to smoke's risk of developing head and neck cancer begins to approach the risk in the general population 15 years after smoking cessation. In addition, people who smoke have a worse prognosis than those who have never smoked. Furthermore, people who continue to smoke after a diagnosis of head and neck cancer have the highest probability of dying compared to those who have never smoked. This effect is seen in patients with HPV-positive head and neck cancer as well. Passive smoking, both at work and at home, also increases the risk of head and neck cancer. Using tobacco together with alcohol is an especially strong risk factor for head and neck cancer, causing 72% of all cases. This rises to 89% when looking specifically at laryngeal cancer. Smokeless tobacco (including products where tobacco is chewed) is also a cause of oral cancer. Cigar and pipe smoking are also important risk factors for oral cancer and have a dose-dependent relationship, with more consumption leading to higher chances of developing cancer. The use of electronic cigarettes may also lead to the development of head and neck cancers due to the substances like propylene glycol, glycerol, nitrosamines, and metals contained therein, which can cause damage to the airways.
=== 16 April === Ukraine and Russia conducted an Orthodox Easter prisoner swap. Some one hundred and thirty Ukrainian POWs were returned to Ukraine in exchange for an unknown number of Russian soldiers. Ukrainian officials said that the remains of some eighty-two deceased Ukrainian soldiers were retrieved from territory controlled by Russia. Chinese defense minister Li Shangfu met with Putin amid reports of Ukrainian forces finding an increasing number of Chinese components in Russian weapons, and leaked classified documents from the United States about China's alleged plans to covertly supply Russia with weapons.
== Pharmacology == In clinical pharmacology, a potentiator is a drug, herb, or chemical that intensifies the effects of a given drug. For example, hydroxyzine or dextromethorphan is used to get more pain relief and anxiolysis out of an equal dose of an opioid medication. The potentiation can take place at any part of the liberation, absorption, distribution, metabolism and elimination of the drug.
This is a list of investigational social anxiety disorder drugs, or drugs that are currently under development for clinical use in the treatment of social anxiety disorder (SAD; or social phobia) but are not yet approved. Chemical/generic names are listed first, with developmental code names, synonyms, and brand names in parentheses. This list was last comprehensively updated in August 2024. It is likely to become outdated with time.
Sources: en.wikipedia.org
==== Cytochrome P450 modulation ==== It has been reported that bicalutamide may have the potential to inhibit the enzymes CYP3A4 and, to a lesser extent, CYP2C9, CYP2C19, and CYP2D6, based on in vitro research. However, no relevant inhibition of CYP3A4 has been observed in vivo with bicalutamide at a dose of 150 mg (using midazolam as a specific marker of CYP3A4 activity). In animals, bicalutamide has been found to be an inducer of certain cytochrome P450 enzymes. However, dosages of 150 mg/day or less have shown no evidence of this in humans. Bicalutamide has been identified as a strong CYP27A1 (cholesterol 27-hydroxylase) inhibitor in vitro. CYP27A1 converts cholesterol into 27-hydroxycholesterol, an oxysterol that has multiple biological functions including direct, tissue-specific activation of the ER (it has been characterized as a selective estrogen receptor modulator) and the liver X receptor. 27-Hydroxycholesterol has been found to increase ER-positive breast cancer cell growth via its estrogenic action, and hence, it has been proposed that bicalutamide and other CYP27A1 inhibitors may be effective as adjuvant therapies to aromatase inhibitors in the treatment of ER-positive breast cancer. In addition to CYP27A1, bicalutamide has been found to bind to and inhibit CYP46A1 (cholesterol 24-hydroxylase) in vitro, but this has yet to be assessed and confirmed in vivo.
=== Obesity === In 1984, researchers at the University of Rochester Medical Center reported that they had performed a double-blind, controlled clinical trial comparing phentermine alone, fenfluramine alone, a combination of phentermine and fenfluramine, and placebo, for weight loss in humans. Weight loss in those receiving the fen-phen combination was significantly greater (8.4±1.1 kg) than in those receiving placebo (4.4±0.9 kg) and equivalent to that of those receiving fenfluramine (7.5±1.2 kg) or phentermine alone (10.0±1.2 kg). This amounts to an additional weight loss of 4±2 kg over the course of 24 weeks. Adverse effects were less frequent with the combination regimen than with the other active (non-placebo) treatments. The authors felt that combining fenfluramine and phentermine capitalized on their pharmacodynamic differences, resulting in equivalent weight loss, fewer adverse effects, and better appetite control.
=== Alternative reductases and oxidases === Many eukaryotic organisms have electron transport chains that differ from the much-studied mammalian enzymes described above. For example, plants have alternative NADH oxidases, which oxidize NADH in the cytosol rather than in the mitochondrial matrix, and pass these electrons to the ubiquinone pool. These enzymes do not transport protons, and, therefore, reduce ubiquinone without altering the electrochemical gradient across the inner membrane. Another example of a divergent electron transport chain is the alternative oxidase, which is found in plants, as well as some fungi, protists, and possibly some animals. This enzyme transfers electrons directly from ubiquinol to oxygen. The electron transport pathways produced by these alternative NADH and ubiquinone oxidases have lower ATP yields than the full pathway. The advantages produced by a shortened pathway are not entirely clear. However, the alternative oxidase is produced in response to stresses such as cold, reactive oxygen species, and infection by pathogens, as well as other factors that inhibit the full electron transport chain. Alternative pathways might, therefore, enhance an organism's resistance to injury, by reducing oxidative stress.
The Space Race (Russian: космическая гонка, romanized: kosmicheskaya gonka, IPA: [kɐsˈmʲitɕɪskəjə ˈɡonkə]) was a 20th-century competition between the Cold War rivals, the United States and the Soviet Union, to achieve superior spaceflight capability. It had its origins in the ballistic missile-based nuclear arms race between the two nations that followed World War II and the onset of the Cold War. The technological advantage demonstrated by spaceflight achievement was seen as necessary for national security, particularly in regard to intercontinental ballistic missile and satellite reconnaissance capability, but also became part of the cultural symbolism and ideology of the time. The Space Race brought pioneering launches of artificial satellites, robotic landers to the Moon, Venus, and Mars, and human spaceflight in low Earth orbit and ultimately to the Moon. Public interest in space travel originated in the 1951 publication of a Soviet youth magazine and was promptly picked up by US magazines. The competition began on July 29, 1955, when the United States announced its intent to launch artificial satellites for the International Geophysical Year. Five days later, the Soviet Union responded by declaring they would also launch a satellite "in the near future". The launching of satellites was enabled by developments in ballistic missile capabilities since the end of World War II. The competition gained Western public attention with the "Sputnik crisis", when the USSR achieved the first successful satellite launch, Sputnik 1, on October 4, 1957.
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 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.