IGF-1 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.
Last reviewed on 2026-07-26. Where a claim depends on a specific study, the study is described rather than over-claimed.
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 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.
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 |
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.
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.
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.
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.
Clearance profiles diverge sharply between the two versions. The albumin-binding molecule stays in plasma for several days, whereas the unmodified analog is largely gone within about half an hour in reported work. Cleavage by dipeptidyl peptidase IV is a major contributor to the short life of the unmodified sequence. These gaps mean the two versions cannot be substituted for each other in study design or in reading results side by side.
=== Chemical reactions === Diallyl disulfide can be readily oxidized to allicin with hydrogen peroxide or peracetic acid. Allicin in turn can hydrolyze giving diallyl disulfide and trisulfide. Reaction of diallyl disulfide with liquid sulfur gives a mixture containing diallyl polysulfides with as many as 22 sulfur atoms in a continuous chain identified. When diallyl disulfide is heated it decomposes giving a complex mixture. The carbon-sulfur bond of diallyl disulfide is 16 kcal mol−1 weaker than the sulfur-sulfur bond (46 kcal mol−1 versus 62 kcal mol−1, respectively), with the consequence that on heating diallyl disulfide gives the allyldithio radical (AllSS•), which through addition to the double bonds in diallyl disulfide followed by fragmentation and subsequent reactions generates numerous organosulfur compounds, many of which are found in trace amounts in distilled garlic oil. In the presence of a catalyst, diallyl disulfide can combine with alkyl halides forming 1-alkylthio-3-allylthio-1-propene and 1,3-di(alkylthio)propene.
=== Books === ——; Wilson, E. B. (1985) [Originally published in 1935]. Introduction to Quantum Mechanics with Applications to Chemistry. Reprinted by Dover Publications. ISBN 978-0-486-64871-2. —— (1939). The Nature of the Chemical Bond and the Structure of Molecules and Crystals. Cornell University Press. —— (1947). General Chemistry: An Introduction to Descriptive Chemistry and Modern Chemical Theory. Freeman. Greatly revised and expanded in 1947, 1953, and 1970. Reprinted by Dover Publications in 1988. —— (1950). College Chemistry: An Introductory Textbook of General Chemistry. Freeman. 2nd edition, 1955. 3rd edition, 1964. —— (1970) [Originally published in 1964]. The Architecture of Molecules. (Illustrated by Roger Hayward). San Francisco: W. H. Freeman and Company. ISBN 978-0-7167-0158-3. Manuscript notes and typescripts (clear images) —— (1958). No more war!. Dodd, Mead & Co. ISBN 978-1-124-11966-3 —— (1977). Vitamin C, the Common Cold and the Flu. Freeman. ISBN 978-0-7167-0360-0. —— (1987). How to Live Longer and Feel Better. Avon. ISBN 978-0-380-70289-3. Cameron, E.; —— (1993). Cancer and Vitamin C: A Discussion of the Nature, Causes, Prevention, and Treatment of Cancer With Special Reference to the Value of Vitamin C. Camino. ISBN 978-0-940159-21-1. —— (1998). Linus Pauling On Peace: A Scientist Speaks Out on Humanism and World Survival. Rising Star Press. ISBN 978-0-933670-03-7. Hoffer, Abram; —— (2004). Healing Cancer: Complementary Vitamin & Drug Treatments. Toronto: CCNM Press. ISBN 978-1-897025-11-6. Ikeda, Daisaku; —— (2008).
In Colombia, Dunkin' Donuts opened its first store in Bogotá in 1983. By 2015, Dunkin' Donuts operated more than 100 stores only in the capital city of the country. As of February 2016, it operates more than 150 stores around the country including locations in the cities of Medellín, Cali, Ibagué, Pereira, Manizales and Barranquilla. In January 2014, Dunkin' Donuts relaunched in England 20 years after it exited the country with its store opening in Harrow, London. There are no Dunkin' Donuts stores in Scotland, Northern Ireland or Wales. On December 5, 2014, Dunkin' Donuts opened their first location in the Nordic region, at the Täby Centrum shopping mall in the outskirts of Stockholm, Sweden. On July 24, 2018, Dunkin' Donuts announced that the company's Swedish operations had filed for bankruptcy and all locations in Sweden would close immediately. On April 1, 2015, the first store in Denmark opened in Copenhagen Central Station and by May 5, 2015, one opened at Roskilde railway station. There is still one under construction in Odense. In early December 2015, Dunkin' Donuts opened their first cafe in 13 years in Warsaw. By 2018, the Polish franchisee, Varsovia Food Company Sp. z o.o., operated five stores across Poland. In August 2018, Dunkin' decided to withdraw from the Polish market, leading the franchisee to terminate its remaining leases. On January 21, 2016, Dunkin' Brands announced a master franchise agreement with Grand Parade Investments Ltd. that called for developing 250 Dunkin' Donuts and 70 Baskin-Robbins outlets throughout South Africa.
== Contents and curation == Because curation resources are finite, accession policies commonly prioritize poorly represented taxa and geographic areas, legally collected material, authoritative identifications, and specimens that can be housed and made available for study.
=== Insulin pricing === In January 2019, lawmakers from the United States House of Representatives sent letters to Eli Lilly and other insulin manufacturers asking for explanations for rapidly raising insulin prices. The annual cost of insulin for people with type 1 diabetes in the US almost doubled from $2,900 to $5,700 over the period from 2012 to 2016. Renewed attention was brought to Eli Lilly's pricing of insulin in November 2022, after a verified Twitter account impersonating Eli Lilly posted on Twitter that insulin would now be free. The following year, the company announced that it would be reducing the out-of-pocket price of insulin to $35 a month. The company also stated that it would lower the price of Humalog from $275 a month to $66 and that it would offer insulin glargine at a 78% discount compared to rival company Sanofi. Despite this, the reduced costs will not apply to Eli Lilly's newer brands of insulin, and the company's pricing is still significantly higher than it was several decades prior.
Sources: en.wikipedia.org
=== Sympathetic hyperactivation === Hyperactivation of the sympathetic nervous system is not a recognized condition in itself, but it is a component of a number of conditions, as well as a possible consequence of taking sympathomimetic drugs. It causes a distinctive set of symptoms including aches and pains, rapid heartbeat, elevated blood pressure, sweating, palpitations, anxiety, headache, paleness, and a drop in blood glucose. If sympathetic activity is elevated for an extended time, it can cause weight loss and other stress-related body changes. The list of conditions that can cause sympathetic hyperactivation includes severe brain injury, spinal cord damage, heart failure, high blood pressure, kidney disease, and various types of stress.
In Western and Asian cultures, in contrast to most Middle Eastern cultures, a majority of men are accustomed to shaving their facial hair, so only a minority of men reveal a beard, even though fast-growing facial hair must be shaved daily to achieve a clean-shaven or beardless appearance. Some men shave because they cannot genetically grow a "full" beard (generally defined as an even density from cheeks to neck), their beard color is genetically different from their scalp hair color, or because their facial hair grows in many directions, making a groomed or contoured appearance difficult to achieve. Some men shave because their beard growth is excessive, unpleasant, or coarse, causing skin irritation. Some men grow a beard or moustache from time to time to change their appearance or visual style. Some men tonsure or head shave, either as a religious practice, a fashion statement, or because they find a shaved head preferable to the appearance of male pattern baldness, or in order to attain enhanced cooling of the skull – particularly for people suffering from hyperhidrosis. A much smaller number of Western women also shave their heads, often as a fashion or political statement. Some women also shave their heads for cultural or social reasons. In India, tradition required widows in some sections of the society to shave their heads as part of being ostracized (see Women in Hinduism § Widowhood and remarriage). The outlawed custom is still infrequently encountered mostly in rural areas. Society at large and the government are working to end the practice of ostracizing widows.
निरन्तरान्धकारितदिगन्तरकन्दलदमन्दसुधारसबिन्दुसान्द्रतरघनाघनवृन्द-सन्देहकरस्यन्दमानमकरन्दबिन्दुबन्धुरतरमाकन्दतरुकुलतल्पकल्पमृ-दुळसिकताजालजटिलमूलतलमरुवकमिलदलघुलघुलयकलितरमणीय-पानीयशालिकाबालिकाकरारविन्दगलन्तिकागलदेलालवङ्गपाटलघनसा-रकस्तूरिकातिसौरभमेदुरलघुतरमधुरशीतलतरसलिलधारानिराकरिष्णुत-दीयविमलविलोचनमयूखरेखापसारितपिपासायासपथिकलोकान् In IAST transliteration:
The insulin produced by bacteria, branded Humulin, was approved for release by the Food and Drug Administration in 1982. In 1988, the first human antibodies were produced in plants. In 1987, a strain of Pseudomonas syringae became the first genetically modified organism to be released into the environment when a strawberry and potato field in California were sprayed with it. The first genetically modified crop, an antibiotic-resistant tobacco plant, was produced in 1982. China was the first country to commercialize transgenic plants, introducing a virus-resistant tobacco in 1992. In 1994, Calgene attained approval to commercially release the Flavr Savr tomato, the first genetically modified food. Also in 1994, the European Union approved tobacco engineered to be resistant to the herbicide bromoxynil, making it the first genetically engineered crop commercialized in Europe. An insect resistant Potato was approved for release in the US in 1995, and by 1996 approval had been granted to commercially grow 8 transgenic crops and one flower crop (carnation) in 6 countries plus the EU. In 2010, scientists at the J. Craig Venter Institute announced that they had created the first synthetic bacterial genome. They named it Synthia and it was the world's first synthetic life form. The first genetically modified animal to be commercialized was the GloFish, a Zebra fish with a fluorescent gene added that allows it to glow in the dark under ultraviolet light. It was released to the US market in 2003.
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.