The short version of synthetic peptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-08-28. Anything still debated is marked as such rather than presented as settled.
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.
A central uncertainty is whether observed metabolic changes translate into meaningful clinical benefits. Study designs vary in dose, duration, and participant characteristics, making comparisons difficult. Independent replication is limited, and the field lacks consensus on optimal endpoints or treatment duration. Ongoing or future studies may clarify mechanism and effect size, but current evidence does not establish a clear therapeutic role. Researchers often call for larger, longer, and better-controlled trials, while questions remain about which patient groups might respond.
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.
Regulatory status varies by country. In the United States, AOD-9604 is not approved as a prescription drug. It is sometimes sold as a research chemical or dietary supplement, though such marketing may fall outside legal frameworks. The World Anti-Doping Agency prohibits its use in sport. Researchers must obtain it through legitimate suppliers and follow institutional rules. Its legal classification continues to evolve as authorities increasingly assess peptide products more broadly.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic peptide fragment | Not a full hormone |
| Molecular target | Proposed adipose tissue lipolysis | Receptor details uncertain |
| Typical research dose | Not established for clinical use | Doses vary across studies |
| Stability in solution | Limited; store cold | Avoid repeated freeze-thaw |
| Regulatory status | Not approved as a drug | Varies by country |
AOD-9604 is a synthetic peptide whose structure corresponds to a C-terminal segment of human growth hormone. It is often described as hGH fragment 176-191, a 16-amino-acid sequence. The peptide was designed to isolate a region of hGH associated with fat metabolism while avoiding the full hormone's growth-promoting actions. Laboratory and commercial materials typically present it as a lyophilized powder for research use. Its identity is defined by amino acid sequence, not by a single brand.
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.
Several names appear in scientific and commercial settings. AOD9604 and AOD-9604 are development codes used interchangeably, while hGH fragment 176-191 describes the same region. The peptide includes a disulfide bond between two cysteine residues, which helps shape its three-dimensional structure. Different suppliers may provide acetate or other salt forms, and purity can vary. These differences matter because analytical tests and biological assays can respond to the specific form being studied.
Early interest in AOD-9604 centered on whether a fragment of human growth hormone could influence fat metabolism without the broader effects of the full hormone. Cell and animal studies reported changes in fat storage and breakdown. Human trials followed, but the results were not strong enough to secure regulatory approval. The compound remains available for laboratory research, and its clinical potential is still described as uncertain. Studies continue to examine its activity and safety profile.
==== Amide formation pathway ==== The formation of an amide using a carbodiimide is a common reaction, but carries the risk of several side reactions. The acid 1 will react with the carbodiimide to produce the key intermediate: the O-acylisourea 2, which can be viewed as a carboxylic ester with an activated leaving group. The O-acylisourea will react with amines to give the desired amide 3 and urea 4. The possible reactions of the O-acylisourea 2 produce both desired and undesired products. The O-acylisourea 2 can react with an additional carboxylic acid 1 to give an acid anhydride 5, which can react further to give the amide 3. The main undesired reaction pathway involves the rearrangement of the O-acylisourea 2 to the stable N-acylurea 6. The use of solvents with low dielectric constants such as dichloromethane or chloroform can minimize this side reaction.
=== MSC based therapy === In certain studies, matrix-induces mesenchymal stem cell implantation showed earlier clinical improvements when compared to simple implantation of chondrocytes. The MSCs promoted cartilage regeneration in knees that had osteoarthritis and also reduced pain and disability.
== Classification == The enzyme subclasses designate the types of components that are being transferred, and the sub-subclasses indicate the reaction processes that provide the driving force for the translocation.
Sources: en.wikipedia.org
== Occurrence == Diallyl disulfide and the related trisulfide are produced by decomposition of allicin, which is released upon breaking the cells of the Alliaceae plants, especially garlic. The diallyl disulfide yield is the highest for the steam distillation of garlic bulbs which contain about 2 wt.% of diallyl disulfide-rich oil. Diallyl disulfide can also be extracted from garlic leaves, but their oil content is significantly lower at 0.06 wt.%.
In his later years, he promoted nuclear disarmament, as well as orthomolecular medicine, megavitamin therapy, and dietary supplements, especially ascorbic acid (commonly known as Vitamin C). None of his ideas concerning the medical usefulness of large doses of vitamins have gained much acceptance in the mainstream scientific community. He was married to the American human rights activist Ava Helen Pauling.
Despite once having hundreds of stores nationwide, Dunkin' Donuts and its market share all but vanished from Canada by the turn of the 21st century. In the late 1990s to early 2000s, the chain began disappearing from all regions of Canada, with its last foothold in the province of Quebec. However, its decline was most apparent in Quebec, where the chain once had 210 stores, but by mid 2017, had only three—the last franchises in the country. By then, only one free standing store had the facilities to make doughnuts fresh on site. The other two were merely shopping-mall food court stands, dependent on the delivery of baked goods from the main store. One of the primary reasons for Dunkin' Donuts' decline was competition with Tim Hortons, similar to Tim Hortons' own decline in the northeastern United States due to heavy competition from Dunkin' Donuts. A group of Dunkin' Donuts franchisees won a C$16.4 million civil court judgement against the parent company for failing to adequately promote the brand in Canada. In September 2018, after 57 years of operating in Canada, Dunkin' Donuts ceased business there when it refused to renew its franchise license to the few remaining stores left. All remaining Canadian locations were closed or rebranded as independent businesses in late 2018, ending the presence of Dunkin' Donuts in the country. Baskin-Robbins, a subsidiary of Dunkin' Brands, continues to operate stores across Canada.
Sources: en.wikipedia.org
It is proposed to promote lipolysis in fat tissue, the breakdown of stored fat into fatty acids and glycerol. The detailed receptor and signaling mechanisms are not fully established.
Because it is a fragment rather than full growth hormone, it is generally described as lacking growth-promoting effects. Some studies suggest it may influence fat metabolism without the same systemic growth effects, though evidence is limited.
Human trials have measured body weight, fat mass, lean mass, lipid levels, and adverse events. Most have been small or short-term, so conclusions about long-term outcomes are limited.
AOD-9604 is a synthetic peptide fragment of human growth hormone, corresponding to amino acids 176-191. It is studied for potential effects on fat metabolism, but it is not approved as a drug in most countries. Its exact mechanism remains under investigation.