This is a working overview of synthetic peptide, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-12-26 and is reviewed periodically as new material appears.
Proposed mechanisms for AOD-9604 focus on fat cells. Laboratory studies suggest the peptide can increase lipolysis, the breakdown of stored fat, and reduce lipogenesis, the formation of new fat. Unlike full human growth hormone, it does not appear to stimulate substantial IGF-1 production in the studies reported so far. Some evidence points to beta-adrenergic signaling, but the precise receptor targets and downstream pathways remain unresolved. The fragment is not thought to act through the classical growth hormone receptor.
Clinical development of AOD-9604 included trials in people with obesity. Reports from early-phase and mid-phase studies described modest or inconsistent changes in body weight. A phase IIb program did not meet its primary endpoint, and the compound was not approved for medical use. Differences in formulation, delivery route, and participant characteristics may explain some of the variation. Later investigations explored whether the peptide might have effects in other tissues, including cartilage.
Regulatory treatment of AOD-9604 is shaped by its classification as a peptide hormone. The World Anti-Doping Agency lists it as a prohibited substance, and many national anti-doping organizations adopt that list. It does not hold approval as a prescription medicine in the United States, the European Union, or other major markets. Products sold online are frequently labeled for research use only and may not undergo independent quality testing. Import and possession rules differ by country, so legal status depends on local law.
AOD-9604 is a synthetic peptide modeled on the C-terminal region of human growth hormone. It corresponds to residues 176-191 of the 191-amino-acid hGH sequence. The fragment is not the full hormone and lacks the receptor-binding region associated with growth and metabolic effects of hGH. Researchers developed it to isolate a specific portion of hGH for study. Its exact sequence and length are often stated in peptide catalogs and patents.
The peptide is frequently described as a growth hormone fragment, although it is chemically distinct from full-length hGH. AOD-9604 contains 16 amino acids and includes two cysteine residues that can form an intramolecular disulfide bond. In solution, this structural feature can influence folding, aggregation, and stability. Published descriptions sometimes call it hGH 176-191 or AOD9604, with spacing and capitalization varying. Such naming differences can complicate literature searches, database entries, and product verification.
| Property | Value | Notes |
|---|---|---|
| Typical storage temperature | -20 °C | Lyophilized peptide; protect from moisture and light. |
| Typical analytical method | HPLC and mass spectrometry | Used to confirm identity and estimate purity. |
| Common synonyms | AOD9604; hGH 176-191 | Naming varies by supplier and publication. |
| Disulfide bonds | One | Affects folded structure and stability. |
| Typical research purity | ≥95% | Value depends on supplier and analytical method. |
Proposed mechanism focuses on lipolysis, the breakdown of stored triglycerides into free fatty acids and glycerol. AOD-9604 is thought to act on adipose tissue without stimulating appetite or affecting blood sugar in the same way as growth hormone. Laboratory studies report increased fat oxidation in some models. The precise receptor interactions and signaling pathways remain incompletely characterized. Researchers have proposed that the peptide may influence fat mobilization through pathways distinct from the full hormone.
Research has examined whether the peptide affects fat mass independently of growth hormone's other actions. Early animal studies suggested reductions in body fat, but species differences and small sample sizes limit interpretation. Human studies have generally been short and have not consistently shown large effects. Some trials measured body composition, lipid profiles, and safety parameters, but the overall picture is one of suggestive yet inconclusive metabolic activity. Findings vary across study populations and protocols.
AOD-9604 is a synthetic peptide whose sequence matches the C-terminal fragment of human growth hormone, specifically residues 176 through 191. This region differs from the full hormone in its receptor interactions. The peptide is not a growth hormone secretagogue and does not bind the growth hormone receptor in the same manner. Researchers have examined it for effects on lipid metabolism, but its exact pharmacological profile remains an active area of study.
Development of AOD-9604 began in the 1990s as scientists sought to isolate metabolic effects of growth hormone without its growth-promoting actions. Early laboratory work focused on fat cells and animal models. Several human trials followed, examining changes in body composition and fat mass. Results have been mixed, and the peptide has not progressed to widespread clinical approval. Interest continues in research settings, particularly regarding its mechanism and potential metabolic targets.
The fragment includes residues that can form an internal disulfide bond between two cysteine positions. This structural feature can influence how the peptide folds and how stable it is in solution. AOD-9604 differs from full-length hGH in size and receptor interactions; it does not contain the entire growth hormone sequence. Published descriptions sometimes use slightly different residue numbering, so sequence information should be checked against primary sources. The molecule is small compared with intact hGH, which affects analytical detection and purification approaches.
Interest in AOD-9604 arose from attempts to separate metabolic effects from growth effects attributed to hGH. Early work explored whether the fragment could influence lipolysis or fat oxidation without promoting growth. Those questions remain partly unresolved because human data are limited and results have varied across studies. The peptide is not a hormone replacement for hGH and is not equivalent to hGH in clinical use. Its research history includes both laboratory studies and commercial marketing claims that are not the same as regulatory approval.
==== Polar uncharged ==== The polar, uncharged amino acids serine (Ser, S), threonine (Thr, T), asparagine (Asn, N) and glutamine (Gln, Q) readily form hydrogen bonds with water and other amino acids. They do not ionize in normal conditions, a prominent exception being the catalytic serine in serine proteases. This is an example of severe perturbation, and is not characteristic of serine residues in general. Threonine has two chiral centers, not only the L (2S) chiral center at the α-carbon shared by all amino acids apart from achiral glycine, but also (3R) at the β-carbon. The full stereochemical specification is (2S,3R)-L-threonine. Because of the presence of phenolic hydroxyl group with a pKa = ~10, tyrosine is best classified as a neutral polar amino acid, but with amphipathic character that makes it less polar than classical small polar amino acid residues.
== Clinical significance == Collagen XXIII plays a role as a biomarker for detection and recurrence of NCLSC cells (non-small cell lung carcinoma) and the reappearance of prostate cancer. Some experiments suggest that collagen XXIII influences cellular adhesion and stimulates metastasis development by facilitating cancer cells growth and survival when they are rounded and not able to spread. It has been shown that loss of collagen XXIII may complicate cellular adhesion and reduce lung cancer cell retention.
== Nutrition and health claims == While peach gum contains dietary fiber and may have properties similar to other soluble fibers, many health claims about its benefits lack scientific evidence. Some research suggests it may have blood sugar-lowering effects similar to other plant-based dietary fibers, but more rigorous clinical studies are needed. Marketing claims about collagen content and anti-aging effects are not supported by scientific evidence, as plants do not produce collagen.
Sources: en.wikipedia.org
==== Employer-provided childcare credit ==== As of January 1, 2026, the employer-provided childcare credit (26 U.S.C. § 45F) is increased from 25% to 40% (or 50% for eligible small businesses) of qualified childcare expenses. The maximum employer-provided childcare tax credit is increased from $150,000 to $500,000 per year (or $600,000 for eligible small businesses). The act also expands qualified childcare expenses to include contracted third parties that provide childcare to the employees.
== Research data == A comparison of the heart mitochondria in rats (7-year maximum life span) and pigeons (35-year maximum life span) showed that pigeon mitochondria leak fewer free-radicals than rat mitochondria, despite the fact that both animals have similar metabolic rate and cardiac output For mammals there is a direct relationship between mitochondrial membrane fatty acid saturation and maximum life span Studies of the liver lipids of mammals and a bird (pigeon) show an inverse relationship between maximum life span and number of double bonds Selected species of birds and mammals show an inverse relationship between telomere rate of change (shortening) and maximum life span Maximum life span correlates negatively with antioxidant enzyme levels and free-radicals production and positively with rate of DNA repair Female mammals express more Mn−SOD and glutathione peroxidase antioxidant enzymes than males. This has been hypothesized as the reason they live longer. However, mice entirely lacking in glutathione peroxidase 1 do not show a reduction in lifespan.
In Japan, the Mister Donut franchise is owned by Duskin Co., Ltd., a part of the Mitsui conglomerate. Mister Donut is the largest donut franchise chain in Japan, with a total of 961 retail shops operating as of March 2021. Keiji Chiba, who was Duskin Company's general manager and director of food industries, adjusted the recipes and gave a higher class image so the company would be successful in the Japanese market. Before the introduction of Mister Donut, the Japanese perceived doughnuts as being snacks for children. The Star wrote in 2007 that "Mister Donut has gained a following among mostly younger Japanese for its American-style doughnuts, decor and music, becoming the country's biggest donut chain." On September 13, 2013, a survey by the Japanese retail research company, Softbrain Field, surveyed close to 6000 Japanese citizens of all ages on their favorite fast food restaurant. Mister Donut came in third, at 17%, behind McDonald's at 33% and MOS Burger at 25%.
Sources: en.wikipedia.org
No. Major drug regulators have not approved AOD-9604 for weight loss or any other therapeutic indication. It remains an investigational compound studied in research settings.
The World Anti-Doping Agency classifies it as a prohibited peptide hormone. Athletes under anti-doping rules are not permitted to use it. Its presence can trigger a doping violation.
It is a fragment of growth hormone rather than a substance that signals the pituitary to release more hormone. Studies have not shown a consistent rise in IGF-1 or full growth hormone. Its metabolic effects, if any, appear separate from those of the complete hormone.
No, it is a synthetic peptide fragment corresponding to a small portion of hGH. It is not the full 191-amino-acid hormone and does not reproduce all of hGH's effects.