This is a working overview of nuclear receptor, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-07-08 and is reviewed periodically as new material appears.
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.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. These receptors help regulate circadian rhythms, lipid metabolism, and inflammatory gene expression. In cell and animal experiments, SR9009 alters transcription of clock-controlled genes and metabolic pathways. The compound is not a hormone and does not resemble classical steroid structures. Its activity depends on binding to the ligand-binding domain of REV-ERB, where it can modify corepressor recruitment.
Research interest in SR9009 grew from studies of circadian biology and metabolic disease. Preclinical reports describe effects on exercise capacity, muscle metabolism, and blood lipid levels in rodents, but these findings come from controlled laboratory settings. The compound has low oral bioavailability in animals, which limits systemic exposure after swallowing. Investigators often use injected routes in experiments to achieve measurable plasma concentrations. Human clinical data are sparse, no approved therapeutic product exists, and whether animal effects translate to humans remains an open question.
Regulatory and sporting contexts treat SR9009 as a prohibited substance in many elite competitions. Its presence on banned lists reflects concerns about performance enhancement and unknown long-term safety. Analytical chemists have developed methods to detect the parent compound and its metabolites in urine and blood. Literature discussions distinguish between in vitro potency, animal pharmacology, and anecdotal human reports. The latter are difficult to verify because products sold online may lack purity or contain different compounds.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic small molecule | Studied as a REV-ERB agonist |
| Molecular formula | C20H24ClN3O4S | Reported for the neutral compound |
| Appearance | Off-white to pale yellow solid | Typical research-grade material |
| Solubility | Sparingly soluble in water | Soluble in solvents such as DMSO |
| Common synonyms | SR9009; Stenabolic | Stenabolic is an informal alias |
REV-ERB proteins help regulate daily cycles in gene expression, including genes tied to lipid and glucose metabolism. SR9009 binds these receptors and alters their activity in cell and animal experiments. Consequences observed in rodents include changes in skeletal muscle oxidative capacity, blood lipid levels, and exercise performance. The precise chain from receptor occupancy to whole-body effects is still an active area of study. Human responses cannot be assumed from rodent data.
Most published work on SR9009 consists of preclinical studies. It is widely sold as a research chemical, a category that does not imply safety, efficacy, or pharmaceutical-grade quality. Sports anti-doping organizations have listed SR9009 as a prohibited substance, and its presence in an athlete sample can lead to sanctions. Legal status differs by country; in several jurisdictions it is not approved for human consumption and may be treated as an unapproved new drug.
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.
Regulatory treatment of SR9009 varies by country and context. It is not approved as a therapeutic drug by agencies such as the United States Food and Drug Administration or the European Medicines Agency. Sports authorities list it as a prohibited substance; the World Anti-Doping Agency classifies it among hormone and metabolic modulators. Legal status for personal possession or sale differs across jurisdictions, and some countries may restrict it under analog or research chemical laws. Buyers who seek verified material often rely on independent laboratory testing because online product labels may not match contents.
In laboratory settings, SR9009 is commonly identified by its molecular structure and its interaction with REV-ERB receptors. Vendors may list it under synonyms such as Stenabolic or REV-ERB agonist, but those names do not define purity or identity. Analytical confirmation typically uses high-performance liquid chromatography with ultraviolet detection or liquid chromatography–mass spectrometry. A reference standard is needed to compare retention time and mass spectrum, because the compound can be confused with related research chemicals.
Handling practices for SR9009 focus on minimizing degradation and contamination. The solid is generally stored desiccated at or below -20 °C, protected from light and moisture. Stock solutions are often prepared in dimethyl sulfoxide or ethanol, then aliquoted to avoid repeated freeze–thaw cycles. Aqueous solubility is low, so formulations for animal studies may require cosolvents or suspending agents. Personnel should follow institutional chemical safety procedures, because toxicological data for humans are incomplete.
Regulatory status varies by country and intended use. Major drug agencies have not granted marketing authorization for SR9009 as a medicine, and it is not listed as a controlled substance in many jurisdictions. It is often sold as a research chemical, a category that may fall outside pharmaceutical manufacturing rules. Buyers should verify local laws and supplier documentation, including certificates of analysis. The lack of standardized quality controls raises concerns about identity, purity, and actual content in products marketed online.
Physicochemical behavior influences handling. SR9009 is described as a solid with limited aqueous solubility, so organic solvents such as dimethyl sulfoxide or ethanol are common in research stock solutions. Aqueous dilution can produce precipitates if the organic content is too low. Light, heat, and repeated freeze-thaw cycles may affect stability. Storage recommendations usually specify a desiccated freezer environment protected from light, but exact stability data depend on the formulation and matrix.
Detection in biological samples can be complicated by rapid metabolism and low circulating concentrations. Some studies report phase I and phase II metabolites, and analytical methods may need to target those species in addition to the parent compound. Immunoassays are not broadly available, so mass spectrometry remains the main confirmatory approach. For anti-doping testing, laboratories look for SR9009 and its metabolites using validated LC-MS methods. Open questions include how long metabolites remain detectable and how different routes of administration alter detection windows.
ACC synthase reaches optimal activity in conditions of pH 8.5 and with Km = 20 um relative to its substrate, SAM. ACC Synthase and ethylene biosynthesis are regulated by a whole host of stimuli. Stresses such as wounding, noxious chemicals, auxin, flooding, and indole-3-acetic acid (IAA) promote ethylene synthesis, creating a positive feedback cycle with ACC synthase, up-regulating its activity. However, it is also inhibited by a number of compounds as well. S-Adenosylethionine can bind as a substrate for ACC synthase (with higher affinity than SAM) and therefore inhibit any reaction with SAM. ACC Synthase is also competitively inhibited by aminoethoxyvinylglycine (AVG) and aminooxyacetic acid (AOA), inhibitors to many pyridoxal phosphate-mediated enzymic reactions. They are natural toxins that cause slow binding inhibition by interfering with the coenzyme pyridoxal phosphate. ACC synthase activity is also inhibited by intermediates of the activated methyl cycle and the methionine-recycling pathway: 5′-methylthioadenosine, α-keto-γ-methylthiobutyric acid, and S-adenosylhomocysteine.
Deoxyribozymes, also called DNAzymes or catalytic DNA, were first discovered in 1994. They are mostly single stranded DNA sequences isolated from a large pool of random DNA sequences through a combinatorial approach called in vitro selection or systematic evolution of ligands by exponential enrichment (SELEX). DNAzymes catalyze variety of chemical reactions including RNA-DNA cleavage, RNA-DNA ligation, amino acids phosphorylation-dephosphorylation, carbon-carbon bond formation, etc. DNAzymes can enhance catalytic rate of chemical reactions up to 100,000,000,000-fold over the uncatalyzed reaction. The most extensively studied class of DNAzymes is RNA-cleaving types which have been used to detect different metal ions and designing therapeutic agents. Several metal-specific DNAzymes have been reported including the GR-5 DNAzyme (lead-specific), the CA1-3 DNAzymes (copper-specific), the 39E DNAzyme (uranyl-specific) and the NaA43 DNAzyme (sodium-specific). The NaA43 DNAzyme, which is reported to be more than 10,000-fold selective for sodium over other metal ions, was used to make a real-time sodium sensor in cells.
7-Chlorokynurenic acid (7-CKA) is a tool compound that acts as a potent and selective competitive antagonist of the glycine site of the NMDA receptor. It produces ketamine-like rapid antidepressant effects in animal models of depression. However, 7-CKA is unable to cross the blood-brain-barrier, and for this reason, is unsuitable for clinical use. As a result, a centrally-penetrant prodrug of 7-CKA, 4-chlorokynurenine (AV-101), has been developed for use in humans, and is being studied in clinical trials as a potential treatment for major depressive disorder, and anti-nociception. In addition to antagonizing the NMDA receptor, 7-CKA also acts as a potent inhibitor of the reuptake of glutamate into synaptic vesicles (or as a vesicular glutamate reuptake inhibitor), an action that it mediates via competitive blockade of vesicular glutamate transporters (Ki = 0.59 mM). 5,7-Dichlorokynurenic acid Evans blue Kynurenic acid Xanthurenic acid
Sources: en.wikipedia.org
Factors that affect absorption include: The way a drug product is designed and manufactured Its physical and chemical properties Other ingredients it contains The physiologic characteristics of the person taking the drug How the drug is stored Types of absorption in pharmacokinetics include the following: Instantaneous absorption: absorption is nearly immediate. A common example is bolus intravenous injection. Zero-order absorption: rate of absorption is constant. A common example is continuous intravenous infusion. First-order absorption: rate of absorption is proportional to the amount of drug remaining to be absorbed. Representative examples include typical cases of oral administration, subcutaneous injection, and intramuscular injection. Gastrointestinal transit time Flip–flop kinetics Absorption of Drugs
Nanoghosts are nanosized vesicles containing a chosen drug delivery payload manufactured from extracted leukocyte membranes with the cell cytoplasm content removed. The use of biological membranes serves to mask the particles from the immune system to reduce the likelihood of an immunogenic response, as well as to extend circulation of the particles in the blood. They are produced by homogenizing the cells to remove the cytosol, and then sonicating the empty cell membranes to create nanoghosts between 100 and 200 nm in diameter. Membranes used to make nanoghosts harvested form red blood cells have been shown to circulate for about 120 days and avoid phagocytotic cells. Neutrophil based nanoghosts retain the chemotaxis capacity of neutrophils to sites of inflammation, which encourages tumor targeting. NK based nanoghosts exhibit metastatic cancer targeting behavior. Monocyte based nanoghosts are effective at infiltrating the tumor microenvironment. Mesenchymal stem cell derived nanoghosts exhibit cancer targeting properties.
Phytoestrogens exert their effects primarily through binding to estrogen receptors (ER). There are two variants of the estrogen receptor, alpha (ER-α) and beta (ER-β) and many phytoestrogens display somewhat higher affinity for ER-β compared to ER-α. The key structural elements that enable phytoestrogens to bind with high affinity to estrogen receptors and display estradiol-like effects are:
The cell-mediated response to the virus and to vectors is poorly characterised, and has been largely ignored in the literature as recently as 2005. Clinical trials using an AAV2-based vector to treat haemophilia B seem to indicate that targeted destruction of transduced cells may be occurring. Combined with data that shows that CD8+ T-cells can recognise elements of the AAV capsid in vitro, it appears that there may be a cytotoxic T lymphocyte response to AAV vectors. Cytotoxic responses would imply the involvement of CD4+ T helper cells in the response to AAV and in vitro data from human studies suggests that the virus may indeed induce such responses, including both Th1 and Th2 memory responses. A number of candidate T cell stimulating epitopes have been identified within the AAV capsid protein VP1, which may be attractive targets for modification of the capsid if the virus is to be used as a vector for gene therapy. There are several steps in the AAV infection cycle, from infecting a cell to producing new infectious particles:
Sources: en.wikipedia.org
Jonathan E. Mangum is an Australian biomedical scientist, entrepreneur, and executive known for his contributions to translational proteomics and the development of diagnostic technologies in oral health. He is a co-founder of Incisive Technologies and the scientific lead behind BlueCheck, a diagnostic tool for early detection of dental caries, which received FDA clearance in 2023. Mangum earned his Bachelor and Master of Science degrees in Biochemistry from the University of Otago in New Zealand (1995–2000). He completed a PhD in Biomedical Sciences at the University of Melbourne in 2013. He also holds a Graduate Certificate in Commercialisation from Melbourne Business School.
Passive immunity is the immunity acquired by the transfer of ready-made antibodies from one individual to another. Passive immunity can occur naturally, such as when maternal antibodies are transferred to the foetus through the placenta, and can also be induced artificially, when high levels of human (or horse) antibodies specific for a pathogen or toxin are transferred to non-immune individuals. Passive immunization is used when there is a high risk of infection and insufficient time for the body to develop its own immune response, or to reduce the symptoms of ongoing or immunosuppressive diseases. Passive immunity provides immediate protection, but the body does not develop memory, therefore the patient is at risk of being infected by the same pathogen later.
Pertussis toxin is produced by virulent Bordetella pertussis and is responsible for the disease of whooping cough, a respiratory disease that can be fatal for infants. The severe, uncontrollable coughing makes it difficult to breathe causing the "whooping" sound that occurs with inhalation. Bordetella pertussis targets cilia of the upper respiratory tract which are damaged by the pertussis toxin, an ADP-ribosyltransferase that targets G-proteins. Cholera, characterized by copious watery diarrhea, is a potentially life-threatening illness transmitted through the fecal–oral route via food or water contaminated with toxigenic Vibrio cholerae. V. cholerae targets the intestines and secretes cholera toxin, an exotoxin and potent enterotoxin that acts as an ADP-ribosyltransferase targeting G-proteins. This causes an increase in intracellular cAMP and forces intestinal cells to expel significant amounts of water and electrolytes into the lumen.
Sources: en.wikipedia.org
SR9009 is a synthetic research compound that activates the REV-ERBα and REV-ERBβ nuclear receptors. It is not an approved drug and has no established human therapeutic use. Most published biological data come from cell and rodent studies.
No. SR9009 is frequently mislabeled as a SARM in online discussions, but it does not target androgen receptors. Its known mechanism involves REV-ERB nuclear receptors and circadian-metabolic gene regulation.
Human clinical data are very limited. There is no approved human use, and safety and efficacy in people are not established. Most evidence comes from preclinical models, so effects observed in animals may not apply to humans.
SR9009 is a synthetic small molecule studied as an agonist of the REV-ERB nuclear receptors. It is not an approved medicine, and its effects in humans are not well characterized.