The short version of AOD-9604 fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-02-24 and is reviewed periodically as new material appears.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | Derived from a fragment of human growth hormone |
| Sequence basis | hGH residues 176-191 | Commonly described as a 16-amino-acid fragment |
| Appearance | White to off-white powder | Typical for lyophilized research peptides |
| Solubility | Soluble in water or aqueous buffer | Exact solubility depends on pH and purity |
| Common synonyms | AOD9604; hGH 176-191 | Spelling and punctuation vary across sources |
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.
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.
AOD-9604 is a synthetic peptide that corresponds to a short section of human growth hormone. It is commonly identified as hGH fragment 176-191 because its sequence matches residues at the C-terminal end of the hormone. The molecule contains sixteen amino acids and is made by solid-phase peptide synthesis. Researchers study it for metabolic effects rather than for the growth-promoting actions associated with full human growth hormone. Its small size distinguishes it from the complete 191-amino-acid hormone.
Commercial AOD-9604 may vary in purity, counterion content, and residual moisture. Certificates of analysis often report HPLC purity, mass confirmation, and appearance, but testing methods differ between suppliers. Independent verification is sometimes used because labeled content may not match actual peptide amount. Stability under different pH and temperature conditions is not fully standardized across studies. Researchers generally treat lyophilized material as the reference form for weighing and reconstitution. Moisture content can affect accurate mass measurement.
AOD-9604 is typically supplied as a lyophilized white to off-white powder. In this form, it is relatively stable when kept cool, dry, and protected from light. Common storage recommendations place it at −20 °C or below for long-term retention. Reconstituted solutions are less stable and are often kept at 2–8 °C for short periods. Freeze-thaw cycles should be minimized because they can promote aggregation or loss of peptide content. Vials are usually sealed under inert gas to reduce oxidation.
Identity and purity are commonly checked with reversed-phase high-performance liquid chromatography and mass spectrometry. RP-HPLC separates the peptide from related impurities and can estimate purity by peak area. Mass spectrometry confirms molecular mass and helps detect sequence variants or truncations. Some laboratories use amino acid analysis or peptide mapping for additional characterization. No single method proves biological activity; these techniques establish chemical identity and purity only. They also require suitable reference standards for confident comparison.
=== rRNA === Ribosomes, the organelles where protein translation takes place, are made from rRNA and ribosomal proteins. Ribosomes may be the best and most abundant example of nucleic acid quaternary structure. The specifics of ribosome structure varies among different kingdoms and species, but all ribosomes are made of a large subunit and a small subunit. Different classes of organisms have ribosomal subunits of different characteristic sizes. The three dimensional association of ribosomal subunits is essential for ribosomal function. The small subunit binds first to mRNA and then the large subunit is recruited. In order for a polypeptide to be formed, proper association of the mRNA and both ribosome subunits must occur. At left, the secondary structure of rRNA in the peptidyl transferase center of the ribosome in yeast. The peptidyl transferase center is where the formation of the peptide bond is catalyzed during translation. At right, the three-dimensional structure of the peptidyltransferase center. The helical rRNA is associated with globular ribosomal proteins. Incoming codons arrive at the A site and move to the P site, where peptide bond formation is catalyzed. One specific three dimensional structure that is commonly observed in rRNA is the A-minor motif. There are four types of A-minor motifs, all of which include many unpaired adenosines. These lone adenosines extend from outward and allow RNA molecules to bind other nucleic acids in the minor groove.
=== Pharmacokinetics === In a healthy person, the biological half-life of tetryzoline is approximately 6 hours, and it is excreted in urine, chemically unchanged, at least in part. In one study, 10 people were given two drops of 0.5 mg/mL of tetryzoline eye drops (0.025–0.05 mg) at 0 hrs, 4 hrs, 8 hrs, and 12 hrs. Within a 24-hour time window, since the last dose of tetryzoline, the blood serum concentration of tetryzoline in the test subjects was 0.068-0.380 ng/mL and the urine concentration was 13–210 ng/mL. Both the blood and the urine levels of tetryzoline reached their maximums approximately 9 hrs after the last dose. These fluid-concentration levels correspond to normal ocular use of tetryzoline; thus, greater concentrations of tetryzoline in the blood and the urine of the user can indicate misuse of the drug or of poisoning with the drug.
==== Adsorption ==== A straightforward method for reversible immobilization, involving the enzymes being adsorbed or attached physically onto a support substance. Adsorption can take place through weak non-specific forces, such as van der waals, hydrogen bonds, and hydrophobic interactions, whereas in ionic bonding the enzymes are bound through salt linkages. Adsorption on glass, alginate beads or matrix: Enzyme is attached to the outside of an inert material. In general, this method is the slowest among those listed here. As adsorption is not a chemical reaction, the active site of the immobilized enzyme may be blocked by the matrix or bead, greatly reducing the activity of the enzyme.
Sources: en.wikipedia.org
=== Nucleic acid delivery === Nucleic acid-based macromolecules such as siRNA, antisense oligonucleotide, decoy DNA, and plasmid are promising biological and pharmacological therapeutics in regulation of gene expression. However, unlike other small-molecular drugs, their development and applications are limited by high molecular weight and negative charges, which results in poor uptake efficiency and low cellular traffic. To overcome these problems, several different delivery systems have been developed, including CPP-nucleic acid conjugate, which is a powerful tool.
40 mg/day: India National Institute of Nutrition, Hyderabad 45 mg/day or 300 mg/week: the World Health Organization 80 mg/day: the European Commission Council on nutrition labeling 90 mg/day (males) and 75 mg/day (females): Health Canada 2007 90 mg/day (males) and 75 mg/day (females): United States National Academy of Sciences 100 mg/day: Japan National Institute of Health and Nutrition 110 mg/day (males) and 95 mg/day (females): European Food Safety Authority
Degeneration of axons of the retinal ganglion cells (the optic nerve) is a hallmark of glaucoma. The inconsistent relationship of glaucomatous optic neuropathy with increased intraocular pressure has provoked hypotheses and studies on anatomic structure, eye development, nerve compression trauma, optic nerve blood flow, excitatory neurotransmitter, trophic factor, retinal ganglion cell or axon degeneration, glial support cell, immune system, aging mechanisms of neuron loss, and severing of the nerve fibers at the scleral edge.
=== Non-Levantine groups claiming Israelite ancestry === Largely owing to the spread of Christianity and Islam globally, several groups of people outside of the Levant have claimed Israelite ancestry on an ethnic or racial basis. These various non-Levantine groups include Mandaeans, Pashtuns, British Israelists, Black Hebrew Israelites, Igbos, Mormons, and the Christian Identity movement. The phenomenon became especially prevalent after the founding of the State of Israel in 1948, as the country's Law of Return grants citizenship to qualified Jews and to non-Jews who are either married to a Jew or provide sufficient evidence of having Jewish ancestry.
Sources: en.wikipedia.org
==== On Unnatural Amino Acids ==== Pd-mediated Sonogashira, Heck, and Suzuki-Miyaura cross-coupling reactions have been applied widely to modify peptides and proteins, where diverse Pd reagents have been developed for the application in aqueous solutions. Those reactions require the protein or peptide substrate bearing unnatural functional groups such as alkyne, aryl halides, and aryl boronic acids, which can be achieved through genetic code expansion or post-translational modifications.
The Sanitary Commission for the Eradication of Hookworm Disease was a Rockefeller-funded campaign from 1909 to 1914 to study and treat hookworm disease in 11 Southern states. Hookworm was known as the "germ of laziness". In 1913, the foundation expanded its work with the Sanitary Commission abroad and set up the International Health Division (also known as International Health Board), which began the foundation's first international public health activities. The International Health Division conducted campaigns in public health and sanitation against malaria, yellow fever, and hookworm in areas throughout Europe, Latin America and the Caribbean including Italy, France, Venezuela, Mexico, and Puerto Rico, totaling fifty-two countries on six continents and twenty-nine islands. The first director was Wickliffe Rose, followed by F.F. Russell in 1923, Wilbur Sawyer in 1935, and George Strode in 1944. A number of notable physicians and field scientists worked on the international campaigns, including Lewis Hackett, Hideyo Noguchi, Juan Guiteras, George C. Payne, Livingston Farrand, Cornelius P. Rhoads, and William Bosworth Castle. In 1936, The Rockefeller Foundation received one of the first awarded Walter Reed Medals from The American Society of Tropical Medicine & Hygiene to recognize its study and control of Yellow Fever. The World Health Organization, seen as a successor to the IHD, was formed in 1948, and the IHD was subsumed by the larger Rockefeller Foundation in 1951, discontinuing its overseas work.
molecular cloning Any of various molecular biology methods designed to replicate a particular molecule, usually a DNA sequence or a protein, many times inside the cells of a natural host. Commonly, a recombinant DNA fragment containing a gene of interest is ligated into a plasmid vector, which competent bacterial cells are then induced to uptake in a process known as transformation. The bacteria, carrying the recombinant plasmid, are then allowed to proliferate naturally in cell culture, so that each time the bacterial cells divide, the plasmids are replicated along with the rest of the bacterial genome. Any functioning gene of interest within the plasmid will be expressed by the bacterial cells, and thereby its gene products will also be cloned. The plasmids or gene products, which now exist in many copies, may then be extracted from the bacteria and purified. Molecular cloning is a fundamental tool of genetic engineering employed for a wide variety of purposes, often to study gene expression, to amplify a specific gene product, or to generate a selectable phenotype.
Sources: en.wikipedia.org
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.
It is commonly described as a 16-amino-acid peptide based on residues 176-191 of human growth hormone. Some sources vary in notation, so checking the stated sequence is useful.
It is not typically described as a standalone natural hormone. The sequence is derived from the C-terminal region of human growth hormone, but the synthetic peptide is a laboratory-made construct.
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.