If you have been reading about NR1D1 and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-05-31. Where a claim depends on a specific study, the study is described rather than over-claimed.
SR9009 is frequently discussed alongside other REV-ERB ligands, including synthetic agonists and natural heme-related molecules. Its selectivity for REV-ERB over related nuclear receptors has been measured in binding and reporter assays, though off-target activity at higher concentrations is possible. The compound is prohibited in sport by the World Anti-Doping Agency, and it is not approved for any medical use in major jurisdictions. Products sold online may be labeled as research chemicals, and their identity and purity are not guaranteed by regulatory review.
SR9009 is a synthetic small molecule that acts on the nuclear receptors REV-ERBα and REV-ERBβ. These receptors are part of the circadian clock machinery and normally repress transcription of certain target genes. In laboratory research, SR9009 is used as a chemical tool to study how REV-ERB activity influences metabolism, inflammation, and daily biological rhythms. The compound is not an approved medicine, and its effects in humans remain largely uncharacterized. It is often described as an investigational agent rather than a therapeutic product.
In rodent studies, SR9009 has been reported to increase mitochondrial content in skeletal muscle and improve exercise endurance under some conditions. These findings led to popular descriptions such as an exercise mimetic, although that term oversimplifies the biology. Effects vary by dose, timing, tissue, and model. The compound's influence on circadian pathways means that time of administration can matter in experiments. Whether similar metabolic changes occur in humans remains largely unexplored in controlled published trials.
Pharmacokinetic data for SR9009 are limited in published literature. Some reports indicate low oral bioavailability and rapid clearance in animals, which complicates interpretation of exposure and effect. Researchers often use injected routes in preclinical work to achieve measurable systemic levels. Analytical studies rely on mass spectrometry to detect the parent compound and its metabolites. Questions about tissue distribution, active metabolites, and long-term consequences remain open. Species differences in metabolism can affect observed half-life and target engagement.
| Property | Value | Notes |
|---|---|---|
| Common name | SR9009 | Also marketed informally as Stenabolic |
| Chemical class | Synthetic REV-ERB agonist | Binds REV-ERBα and REV-ERBβ |
| Molecular formula | C24H30ClN3O4S | Approximate molecular weight 492 g/mol |
| CAS Registry Number | 1379686-30-2 | Identifier for the parent compound |
| Regulatory status | Not approved for human use | Prohibited in sport by WADA |
Laboratory samples of SR9009 are typically handled as research chemicals rather than pharmaceuticals. Suppliers usually state that the material is for research use only and not for human or veterinary administration. Storage recommendations generally call for a freezer at approximately −20 °C, protection from light, and a desiccated environment. The solid is often described as a white to off-white powder. Solubility is commonly reported in organic solvents such as dimethyl sulfoxide and ethanol, with low solubility in water.
Analytical identification and purity assessment often use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Liquid chromatography–tandem mass spectrometry is used to detect and quantify SR9009 in biological matrices, including urine and blood, for anti-doping or pharmacokinetic studies. Nuclear magnetic resonance spectroscopy can confirm molecular structure. Stability depends on form and storage: the solid is generally more stable than solutions, and repeated freeze–thaw cycles may degrade samples. Purity is typically reported as a percentage from a certificate of analysis.
Analytical chemists detect SR9009 with liquid chromatography-tandem mass spectrometry, commonly abbreviated LC-MS/MS. Sample preparation may involve protein precipitation, liquid-liquid extraction, or solid-phase extraction before analysis. Laboratories can target the parent compound or its metabolites, depending on the matrix and the purpose of testing. Anti-doping methods require sensitive and specific assays because concentrations in biological samples can be low. Reference standards and validated methods are essential for reliable identification and quantification.
Regulatory agencies have not approved SR9009 for human therapeutic use. It is typically sold as a research chemical with labels stating that it is not for human consumption. The World Anti-Doping Agency prohibits the substance in sport, generally under the category of non-approved substances. Customs and national laws may restrict importation, sale, or possession. Product quality and legal status can vary by country and vendor, and therapeutic claims are not permitted in regulated advertising because the compound lacks approval.
Several misconceptions surround SR9009. It is often described as a SARM, a steroid, or an exercise pill, but its known target is the REV-ERB receptor family. Rodent studies have examined exercise capacity and metabolic markers, yet human outcomes remain unproven. Oral bioavailability appears low in animals, and human pharmacokinetics are not well characterized. Online products may contain impurities or different compounds, so identity and purity testing are important for research use.
Identity and purity of SR9009 samples are usually checked with chromatographic and spectrometric methods. High-performance liquid chromatography can separate the compound from related impurities, while mass spectrometry provides molecular mass confirmation. Nuclear magnetic resonance spectroscopy may be used for structural verification in research settings. No single method proves biological activity, and certificates of analysis should be reviewed alongside raw data. Independent testing is often needed because online products vary widely.
SR9009 stability depends on temperature, moisture, light, and solvent. Solid material is generally kept cool and dry, while solutions may require protection from repeated warming and cooling. Degradation can appear as color changes, precipitate, or new chromatographic peaks. Researchers should follow supplier instructions and their own stability data. Long-term storage conditions for human use have not been established because the compound lacks approved clinical formulation.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ, also called NR1D1 and NR1D2. These receptors help regulate circadian rhythms and metabolic gene programs. The compound was developed for laboratory research, not as an approved therapeutic. Its identity is distinct from steroid hormones and selective androgen receptor modulators. Scientific interest centers on how REV-ERB activation changes gene expression in cells and animal models.
At the molecular level, SR9009 binds the ligand-binding domain of REV-ERB and strengthens recruitment of corepressor proteins such as NCoR and HDAC3. This increases repression of target genes, including Bmal1 and other clock-controlled and metabolic genes. In rodent studies, such changes have been linked to altered lipid handling, glucose metabolism, and energy expenditure. The precise chain of events between receptor binding and whole-body effects remains an active area of research. Findings in animals do not automatically translate to humans.
Laboratory studies often administer SR9009 by injection because oral absorption appears poor in rodents. Reported pharmacokinetic properties include rapid metabolism and low systemic exposure after oral dosing. Human pharmacokinetic data are sparse, so absorption, distribution, metabolism, and excretion in people are not well defined. Some research explores related REV-ERB compounds with improved drug-like properties. Regulatory approval for any REV-ERB agonist as a human medicine has not been granted to date.
The majority of serpin diseases are due to protein aggregation and are termed "serpinopathies". Serpins are vulnerable to disease-causing mutations that promote formation of misfolded polymers due to their inherently unstable structures. Well-characterised serpinopathies include α1-antitrypsin deficiency (alpha-1), which may cause familial emphysema, and sometimes liver cirrhosis, certain familial forms of thrombosis related to antithrombin deficiency, types 1 and 2 hereditary angioedema (HAE) related to deficiency of C1-inhibitor, and familial encephalopathy with neuroserpin inclusion bodies (FENIB; a rare type of dementia caused by neuroserpin polymerisation). Each monomer of the serpin aggregate exists in the inactive, relaxed conformation (with the RCL inserted into the A-sheet). The polymers are therefore hyperstable to temperature and unable to inhibit proteases. Serpinopathies therefore cause pathologies similarly to other proteopathies (e.g. prion diseases) via two main mechanisms. First, the lack of active serpin results in uncontrolled protease activity and tissue destruction. Second, the hyperstable polymers themselves clog up the endoplasmic reticulum of cells that synthesize serpins, eventually resulting in cell death and tissue damage. In the case of antitrypsin deficiency, antitrypsin polymers cause the death of liver cells, sometimes resulting in liver damage and cirrhosis. Within the cell, serpin polymers are slowly removed via degradation in the endoplasmic reticulum.
Note that for Drug A, the % increase in unbound fraction is 100% – hence, Drug A's pharmacological effect can potentially double (depending on whether the free molecules get to their target before they are eliminated by metabolism or excretion). This change in pharmacologic effect could have adverse consequences. However, this effect is really only noticeable in closed systems where the pool of available proteins could potentially be exceeded by the number of drug molecules. Biological systems, such as humans and animals, are open systems where molecules can be gained, lost or redistributed and where the protein pool capacity is almost never exceeded by the number of drug molecules. A drug that is 99% bound means that 99% of the drug molecules are bound to blood proteins not that 99% of the blood proteins are bound with drug. When two, highly protein-bound drugs (A and B) are added into the same biological system it will lead to an initial small increase in the concentration of free drug A (as drug B ejects some of the drug A from its proteins). However, this free drug A is now more available for redistribution into the body tissues and/or for excretion. This means the total amount of drug in the system will decrease quite rapidly, keeping the free drug fraction (the concentration of free drug divided by the total drug concentration) constant and yielding almost no change in clinical effect.
== Elements == An expression vector has features that any vector may have, such as an origin of replication, a selectable marker, and a suitable site for the insertion of a gene like the multiple cloning site. The cloned gene may be transferred from a specialized cloning vector to an expression vector, although it is possible to clone directly into an expression vector. The cloning process is normally performed in Escherichia coli. Vectors used for protein production in organisms other than E.coli may have, in addition to a suitable origin of replication for its propagation in E. coli, elements that allow them to be maintained in another organism, and these vectors are called shuttle vectors.
SELDI technology was developed by T. William Hutchens and Tai-Tung Yip at Baylor College of Medicine in 1993. Hutchens and Yip attached single-stranded DNA to agarose beads and used the beads to capture lactoferrin, an iron-binding glycoprotein, from preterm infant urine. The beads were incubated in the sample and then removed, washed, and analyzed with a MALDI-MS probe tip. This research led to the idea that MALDI surfaces could be derivatized with SEAC devices; the technique was later described by Hutchens and Yip in 1998. SELDI technology was first commercialized by Ciphergen Biosystems in 1997 as the ProteinChip system, and is now produced and marketed by Bio-Rad Laboratories.
Sources: en.wikipedia.org
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==== Legal Considerations ==== In the United States brands applied by any method often must be registered with a state or county office. In some jurisdictions, it is illegal to brand an animal without first registering the design with a state office. The following table summarizes the legal recognition and requirements for equine freeze brands in the United States:
== History == Hypoglycemia was first recognized in the 19th century. In the 1920s, after the discovery of insulin and its use in the treatment of diabetics, hyperinsulinism was suspected to be a cause of hypoglycemia in nondiabetics. A pioneering description of hyperinsulinism as a cause of hypoglycemia was published by Seale Harris in 1924. The first report of a surgical cure of hypoglycemia by removing an islet cell tumour was in 1929. An insulinoma removed from a woman in Munich provided insulin mRNA that was used in the first human gene cloning experiment. In 1979, Axel Ullrich cloned this gene into E. coli. Most therapeutic insulin used today derives from this woman's tumour.
Sources: en.wikipedia.org
SR9009 is a synthetic research compound that binds and modulates the nuclear receptors REV-ERBα and REV-ERBβ. It is used in laboratory studies of circadian biology and metabolism, not as an approved medicine. It is also known by the informal name Stenabolic.
No. SR9009 has not been approved as a therapeutic drug in the United States, European Union, or other major markets. Human safety and efficacy data are very limited. Its presence in consumer products does not imply regulatory approval.
The World Anti-Doping Agency lists SR9009 as a prohibited substance because it can alter gene expression and metabolic pathways relevant to performance. The ban applies at all times, not only during competition. Detection relies on laboratory methods such as mass spectrometry.
It is a synthetic research compound that activates REV-ERB nuclear receptors. It is not an approved drug or dietary supplement. Most information comes from cell and animal studies.