REV-ERB comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-09-10. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
REV-ERB proteins typically suppress gene expression by recruiting corepressor complexes to DNA response elements. SR9009 binds these receptors and strengthens that repressive action in cell-based assays. Studies in rodents have reported changes in lipid handling, mitochondrial function, and exercise capacity after treatment. Such findings are often cited as evidence for metabolic effects, but species differences and limited pharmacokinetic data make direct translation to humans uncertain. Researchers continue to examine which effects are robust and which depend on specific experimental conditions.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Common supplier description |
| Solubility | Soluble in DMSO and ethanol | Low solubility in water |
| Typical storage | −20 °C, desiccated, dark | For research samples |
| Analytical method | LC-MS/MS | Used for detection and quantification |
| Regulatory status | Prohibited in sport | WADA metabolic modulator class |
Storage conditions for research-grade SR9009 generally involve a freezer at approximately minus twenty degrees Celsius, sometimes lower for long-term preservation. Containers should remain tightly closed and protected from light. Desiccants may be used to limit moisture uptake. Solutions are often stored in aliquots to avoid repeated warming and cooling. Stability data for the compound under various conditions are limited, so laboratories typically follow supplier recommendations and verify performance through periodic analytical checks rather than assuming indefinite stability.
Identity and purity testing for SR9009 commonly uses liquid chromatography coupled with tandem mass spectrometry. This method separates the compound from matrix components and detects it by mass-to-charge transitions, providing sensitive and specific confirmation. Nuclear magnetic resonance spectroscopy can support structural identification, while high-performance liquid chromatography with ultraviolet detection may estimate purity. Because online products labeled as SR9009 may contain other substances or no active compound at all, independent verification is important in research settings. Certificates of analysis are useful but not a substitute for in-house testing.
Laboratory samples of SR9009 are typically supplied as a white to off-white powder. The compound dissolves readily in organic solvents such as dimethyl sulfoxide and ethanol, while its solubility in water is low. Because of this solubility profile, researchers often prepare concentrated stock solutions in an organic solvent before diluting them into aqueous assay buffers. Light exposure, moisture, and repeated freeze-thaw cycles can degrade many small molecules, so handling procedures usually aim to minimize these factors. Purity is commonly checked before use.
SR9009 is a synthetic small molecule developed as an agonist of the nuclear receptors REV-ERBα (NR1D1) and REV-ERBβ (NR1D2). These receptors help regulate circadian rhythms and metabolic gene expression. In cell and animal studies, SR9009 alters transcription of genes involved in lipid metabolism, inflammation, and mitochondrial function. It is not an approved medicine, and its pharmacological profile in humans remains largely uncharacterized. The compound is frequently discussed in the context of circadian biology and metabolic research rather than clinical use.
Preclinical reports have linked SR9009 to improved endurance and altered energy expenditure in rodents. Such findings have prompted interest in whether REV-ERB activation can influence skeletal muscle metabolism. However, the reported effects depend on dose, route, and experimental model, and replication across laboratories is limited. Human trials have not established comparable outcomes, so claims about exercise performance remain speculative. The absence of controlled human data is a central limitation in interpreting these observations.
The mechanism of action involves binding to REV-ERB receptors and recruiting corepressor complexes, which represses target gene transcription. This contrasts with many nuclear receptor agonists that activate transcription. Downstream effects may include changes in autophagy, mitochondrial biogenesis, and lipid handling, but the precise pathways remain an active area of study. Whether these molecular events translate into meaningful physiological effects in humans is unresolved. Most evidence comes from cultured cells and rodent models rather than human participants.
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.
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.
Tyrosine hydroxylase activity is increased in the short term by phosphorylation. The regulatory domain of tyrosine hydroxylase contains multiple serine (Ser) residues, including Ser8, Ser19, Ser31 and Ser40, that are phosphorylated by a variety of protein kinases. Ser40 is phosphorylated by the cAMP-dependent protein kinase. Ser19 (and Ser40 to a lesser extent) is phosphorylated by the calcium-calmodulin-dependent protein kinase. MAPKAPK2 (mitogen-activated-protein kinase-activating protein kinase) has a preference for Ser40, but also phosphorylates Ser19 about half the rate of Ser40. Ser31 is phosphorylated by ERK1 and ERK2 (extracellular regulated kinases 1&2), and increases the enzyme activity to a lesser extent than for Ser40 phosphorylation. The phosphorylation at Ser19 and Ser8 has no direct effect on tyrosine hydroxylase activity. But phosphorylation at Ser19 increases the rate of phosphorylation at Ser40, leading to an increase in enzyme activity. Phosphorylation at Ser19 causes a two-fold increase of activity, through a mechanism that requires the 14-3-3 proteins. Phosphorylation at Ser31 causes a slight increase of activity, and here the mechanism is unknown. Tyrosine hydroxylase is somewhat stabilized to heat inactivation when the regulatory serines are phosphorylated. Tyrosine hydroxylase is mainly present in the cytosol, although it also is found in some extent in the plasma membrane. The membrane association may be related to catecholamine packing in vesicles and export through the synaptic membrane.
Half-Life was followed by an expansion pack, Opposing Force, on November 1, 1999, developed by Gearbox Software. Players control US Marine corporal Adrian Shephard, who fights a new group of aliens and black operations units. Opposing Force was received favorably by critics, many citing the game as being as influential on setting expansion pack standards as the original game had been in influencing the overall genre. The game won the Computer Game of the Year Interactive Achievement Award of 2000 from the Academy of Interactive Arts & Sciences.
== Function == Exercise causes increased expression in muscle of peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1alpha), which is involved in adaptation to exercise. In mice, this causes production of the FNDC5 protein which is cleaved to give a new product irisin. Due to its production through a mechanism initiated by muscular contraction, irisin has been classified as a myokine.
Sources: en.wikipedia.org
The acetyl group of acetylornithine is removed by the enzyme acetylornithinase (AO) or ornithine acetyltransferase (OAT), and this yields ornithine. Then, the enzymes citrulline and argininosuccinate convert ornithine to arginine.
End of discussion." Sanders supports establishing worker-owned cooperatives and introduced legislation numerous times from the 1990s to the 2020s that would aid workers who want to "form their own businesses or to set up worker-owned cooperatives." As early as 1976, Sanders proposed workplace democracy, saying, "I believe that, in the long run, major industries in this state and nation should be publicly owned and controlled by the workers themselves." Likewise, he supports empowering and expanding labor unions to advance union democracy. In 1987, Sanders defined democracy as public ownership and workers' self-management in the workplace, saying: "Democracy means public ownership of the major means of production, it means decentralization, it means involving people in their work. Rather than having bosses and workers it means having democratic control over the factories and shops to as great a degree as you can." In his 2020 run for president, he proposed that 20% of stocks in corporations with over $100 million in annual revenue be owned by the corporation's workers and that 45% of the board of directors of corporations with over $100 million in annual revenue be elected by the workers of that corporation.
==== Nanoparticles ==== An efficient way to synthesize protein-polymer hybrid nanoparticles is to take advantage of photoinitiated reversible addition−fragmentation chain transfer (RAFT) polymerization-induced self-assembly(PISA) by using multi-RAFT modified bovine serum albumin (BSA) as a macromolecular chain transfer agent. RAFT mediated growth of the PHPMA chains will graft from the BSA-RAFT, and increase the hydrophobicity of the star BSA−PHPMA conjugates. At the critical aggregation concentration, they form nanoparticles due to the hydrophobic interactions. The resulting nanoparticles show excellent encapsulation capability for both hydrophobic and hydrophilic molecules, such as cancer drugs and DNA. A rather easy method to prepare protein-polymer hybrid nanoparticles is nanoprecipitation. Spherical nanoparticles composed of BSA-PMMA with diameters of around 100 nm were obtained and the water insoluble chemotherapeutic drug camptothecin was encapsulated within the hydrophobic core consisting of PMMA. Such protein-polymer hybrid nanoparticles possess tunable sizes and surface charges, have attractive bio-compatibilities and allow efficient cell uptake. Camptothecin-encapsulated BSA-PMMA nanoparticles revealed enhanced anti-tumor activity both in vitro and in animals. Beyond the nanoscale, protein-polymer conjugate could also be used as building blocks for constructing more complicated structures such as microcapsules through hydrophobic interactions.
Temperature-responsive polymers or thermoresponsive polymers are polymers that exhibit drastic and discontinuous changes in their physical properties with temperature. The term is commonly used when the property concerned is solubility in a given solvent, but it may also be used when other properties are affected. Thermoresponsive polymers belong to the class of stimuli-responsive materials, in contrast to temperature-sensitive (for short, thermosensitive) materials, which change their properties continuously with environmental conditions. In a stricter sense, thermoresponsive polymers display a miscibility gap in their temperature-composition diagram. Depending on whether the miscibility gap is found at high or low temperatures, either an upper critical solution temperature (UCST) or a lower critical solution temperature (LCST) exists.
Sources: en.wikipedia.org
Legality depends on the country and the intended use. In many places it is sold as a research chemical, but sports and medicine regulations restrict it.
Detection commonly uses liquid chromatography–tandem mass spectrometry. This method can identify the compound in urine or blood at low concentrations.
Typical guidance is −20 °C, dry, and protected from light. Solutions should be aliquoted and limited freeze–thaw cycles should be used.
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.