circadian clock is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-07-21. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Not approved for human use | Research-use-only status in many markets |
| WADA status | Prohibited in sport | Generally listed as a non-approved substance |
| Detection technique | LC-MS/MS | Common for urine and blood analysis |
| Common alias | Stenabolic | Informal market nickname, not a pharmacopoeial name |
| Purity check | HPLC or LC-UV | Independent certificate of analysis is typical |
Because REV-ERB receptors are core clock components, SR9009 has been examined for effects on daily rhythms as well as metabolism. Research has explored whether the compound can shift or reinforce circadian gene expression in tissues such as liver and muscle. Some studies report improved metabolic markers in obese or diabetic mice, while others show context-dependent responses. Questions remain about which effects are direct, which are secondary to timing, and how they might differ across species.
SR9009 is a synthetic small molecule studied as an agonist of REV-ERB nuclear receptors. REV-ERB alpha and REV-ERB beta help regulate circadian rhythms and metabolic gene expression. In laboratory research, SR9009 has been used to probe how these receptors affect skeletal muscle, liver, and adipose tissue. The compound was identified in academic drug-discovery work and is often described in scientific literature by its chemical name and research code. It is not an approved medicine, and human clinical data remain limited or absent.
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.
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.
SR9009 is frequently discussed in fitness and research-chemical contexts, yet it has no approved medical indication. Regulatory agencies have not authorized it for human use, and it is not a standard prescription drug. Some sports organizations list it as a prohibited substance because of its potential performance-enhancing properties. Published human data are sparse, so claims about its effects in people often rely on animal models or anecdotal reports. Quality and identity of online materials can vary widely.
SR9009 is a synthetic small molecule studied as a REV-ERB agonist. REV-ERBα and REV-ERBβ are nuclear receptors that help regulate circadian rhythms and metabolic gene expression. The compound was identified in academic screening efforts to find synthetic ligands for these receptors. In cell and animal studies, SR9009 alters transcription of genes involved in lipid and glucose metabolism, and it can shift circadian behavior. It is not an approved therapeutic agent.
Mechanistically, SR9009 binds the ligand-binding domain of REV-ERBα/β and enhances recruitment of corepressor complexes. This represses target genes rather than activating them. Because REV-ERB proteins normally compete with ROR proteins at shared response elements, the net effect depends on tissue and timing. Researchers use SR9009 to probe how nuclear receptor signaling links the clock to metabolism, inflammation, and muscle biology. Findings are largely preclinical, and the precise contribution of each receptor subtype remains under study.
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.
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.
In early 2009, the Purchase Brothers, a Toronto-based film company, released a five-minute film based on Half-Life 2: Episode One, Half-Life: Escape from City 17. The film combines live-action footage with 3D animation created using the Source SDK. It was well received by Valve. On August 25, 2010, they released a nearly 15-minute-long sequel.
Aspirin: may increase valproate concentrations. May also interfere with valproate's metabolism. Benzodiazepines: may cause CNS depression and there are possible pharmacokinetic interactions. Carbapenem antibiotics: reduce valproate levels, potentially leading to seizures. Cimetidine: inhibits valproate's metabolism in the liver, leading to increased valproate concentrations. Erythromycin: inhibits valproate's metabolism in the liver, leading to increased valproate concentrations. Ethosuximide: valproate may increase ethosuximide concentrations and lead to toxicity. Felbamate: may increase plasma concentrations of valproate. Mefloquine: may increase valproate metabolism combined with the direct epileptogenic effects of mefloquine. Oral contraceptives: may reduce plasma concentrations of valproate. Primidone: may accelerate metabolism of valproate, leading to a decline of serum levels and potential breakthrough seizure. Rifampicin: increases the clearance of valproate, leading to decreased valproate concentrations. Warfarin: valproate may increase free warfarin concentration and prolong bleeding time. Zidovudine: valproate may increase zidovudine serum concentration and lead to toxicity.
On July 25, 2018, the Ford government passed Bill 2, which "put a severe dent into the operations of Hydro One", a former Crown corporation which went public in November 2015. The Toronto-based Hydro One is the province's "largest electricity transmission and distribution service provider" with "nearly 1.4 million customers". Hydro One was established under the Business Corporations Act Crown corporation under the Government of Ontario. Bill 2 places a cap on the compensation allowed for executive members of the board of directors, and gave Ford's provincial government a "direct say in the naming of directors" representing a major shift from what was agreed upon between shareholders and the government when Hydro One went public three years earlier. Under Premier Ford, the CEO and the entire board of directors were replaced. The former CEO, Mayo Schmidt was replaced by Tim Hodgson, a Ford appointee, who took on his new position in August 2019 with an annual salary of $120,000. Hydro One was in the process of acquiring American energy firm Avista Inc., when "U.S. regulators scuttled" the purchase "costing the Toronto-based company a $140 million termination penalty." The Washington Utilities and Transportation Commission said that they blocked the purchase of Avista because of concerns about the independence of Hydro One from the Ontario provincial government. Reducing Ontario consumer electricity costs by 12% was one of the campaign promises made by the Conservative Party. government had promised to cut consumers' electricity prices 12%.
== History == Vacutainer technology was developed in 1947 by Joseph Kleiner, and is currently marketed by Becton Dickinson (B-D). The Vacutainer was preceded by other vacuum-based phlebotomy technology such as the Keidel vacuum. The plastic tube version, known as Vacutainer PLUS, was developed at B-D in the early 1990s by E. Vogler, D. Montgomery and G. Harper amongst others of the Surface Science Group as US patents 5344611, 5326535, 5320812, 5257633 and 5246666. Vacutainers are widely used in phlebotomy in developed countries due to safety and ease of use. Vacutainers have the advantage of being prepared with additives, allowing easy multi-tube draws, and having a lower chance of hemolysis. In developing countries, it is still common to draw blood using a syringe or syringes. Many brands have now started manufacturing Vaccutainer such as Vacu-8, Hemo Tube and Hemo Vac Plus. These tubes are now also available in pre-barcoded forms.
Sources: en.wikipedia.org
=== Anti-degradation === Many biological agents and chemical compounds have been used in order to prevent matrix-degrading enzymes that actively work to degrade cartilage. Monoclonal antibodies, most commonly studied being 12F4.1H7, work to specifically suppress ADAMTS-5-induced aggrecan release. This in turn helps to slow down cartilage degradation and osteophyte formation.
== Functions == The interstitial fluid is a reservoir and transportation system for nutrients and solutes distributing among organs, cells, and capillaries, for signaling molecules communicating between cells, and for antigens and cytokines participating in immune regulation. The structure of the gel reticulum plays a role in the distribution of solutes across the interstitium, as the microstructure of the extracellular matrix in some parts excludes larger molecules (exclusion volume). The density of the collagen matrix fluctuates with the fluid volume of the interstitium. Increasing fluid volume is associated with a decrease in matrix fiber density, and a lower exclusion volume. The total fluid volume of the interstitium during health represents about 20% of body weight, but the interstitial space is dynamic and may change in volume and composition during immune responses and in conditions such as cancer, specifically within the interstitium of tumors. The amount of interstitial fluid varies from about 50% of the tissue weight in skin to about 10% in skeletal muscle. Interstitial fluid pressure is variable, ranging from −1 to −4 mmHg in tissues like the skin, intestine and lungs to 21 to 24 mmHg in the liver, kidney and myocardium. Generally, increasing interstitial volume is associated with increased interstitial pressure and microvascular filtration.
=== Natural occurrence === Earth has retained all of the noble gases that were present at its formation except helium. Krypton's concentration in the atmosphere is about 1 ppm. It can be extracted from liquid air by fractional distillation. The amount of krypton in space is uncertain, because measurement is derived from meteoric activity and solar winds. The first measurements suggest an abundance of krypton in space.
=== Venom === Rattlesnake venom is hemotoxic, destroying tissue, causing necrosis and coagulopathy (disrupted blood clotting). In the U.S., the tiger rattlesnake (C. tigris) and some varieties of the Mojave rattlesnake (C. scutulatus) also have a presynaptic neurotoxic venom component known as Mojave type A toxin, which can cause severe paralysis. However, most North American rattlesnakes are not neurotoxic. Although it has a comparatively low venom yield, the venom toxicity of C. tigris is considered to be among the highest of all rattlesnake venoms, and among the highest of all snakes in the Western Hemisphere based on LD50 studies conducted on laboratory mice. C. scutulatus is also widely regarded as producing one of the most toxic snake venoms in the Americas, based on LD50 studies in laboratory mice. Rattlesnake venom is a mixture of five to fifteen enzymes, various metal ions, biogenic amines, lipids, free amino acids, proteins, and polypeptides. More specifically, there are three main families of toxins in rattlesnakes: phospholipases A2 (PLA2s), snake venom metalloproteinases (SVMPs), and snake venom serine proteinases (SVSPs). It contains components meant to immobilize and disable the prey, as well as digestive enzymes, which break down tissue to prepare for later ingestion. The venom is very stable, and retains its toxicity for many years in storage. Snake venom, in general, has a complex and ongoing evolutionary process, and rattlesnake venom is no different. The primary mechanisms of evolution are both gene duplication and gene loss events.
=== Sickle Cell === Sickle-cell disease changes the shape of red blood cells from round to sickle shaped. In the most common variant of sickle-cell disease, the 20th nucleotide of the gene for the beta chain of hemoglobin is altered from the codon GAG to GTG. Thus, the 6th amino acid, glutamic acid, is substituted by valine—notated as an "E6V" or a "Glu6Val" mutation—which causes the protein to be sufficiently altered with a sickle-cell phenotype. The affected cells cause issues in the bloodstream as they can become sticky due to their improper ion transport leading to them being susceptible to water loss. This can cause a buildup of blood cells that obstructs blood flow to any organ in the body.
Sources: en.wikipedia.org
== Products == The company's research and development activities are focused on drugs for the treatment of severe, resistant bacterial infections and life-threatening, invasive fungal diseases. Basilea's products are aimed at diseases that have so far been insufficiently treatable. The company markets the following products exclusively through licence and distribution partners: Ceftobiprole (trade name Zevtera/Mabelio) is a broad-spectrum antibiotic administered intravenously for community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP) in adults. It has an active effect against the bacterium Staphylococcus aureus (MRSA), including methicillin-resistant strains, and against penicillin-resistant Streptococcus pneumoniae (PRSP) bacteria, as well as against gram-negative pathogens such as Enterobacteriaceae. Isavuconazole (trade name Cresemba) is an intravenous and oral antifungal agent for the treatment of patients with invasive aspergillosis and invasive mucormycosis. While Astellas is responsible for the commercialisation of Cresemba in the USA, the pharmaceutical group Pfizer covers the commercialisation in most of Europe and also distributes Cresemba in China and the Asia–Pacific (APAC) area. Basilea's distribution partner in the MENA region is Hikma Pharmaceuticals LLC; Knight Therapeutics Inc. commercialises the antifungal Cresemba in South America.
The four substrates of this enzyme are (+)-sabinene, reduced nicotinamide adenine dinucleotide phosphate (NADPH), oxygen, and a proton. It products are (+)-sabinol, oxidised NADP+, and water. The enzyme is a monooxygenase isolated from Salvia officinalis (common sage). Its active centre is a cytochrome P450.
As a result, the different nuclear spin states have different energies in a non-zero magnetic field. In less formal language, we can talk about the two spin states of a spin 1/2 as being aligned either with or against the magnetic field. If γ is positive (true for most isotopes used in NMR) then m = 1/2 ("spin up") is the lower energy state. The energy difference between the two states is:
If this arrangement is clockwise, it is assigned an R configuration; if it is counterclockwise, it is assigned an S configuration. In contrast, steroid nomenclature uses α and β to denote stereochemistry at chiral centers. The α and β designations are based on the orientation of substituents relative to each other in a specific ring system. In general, α refers to a substituent that is oriented towards the plane of the ring system, while β refers to a substituent that is oriented away from the plane of the ring system. In steroids drawn from the standard perspective used in this paper, α-bonds are depicted on figures as dashed wedges and β-bonds as solid wedges. The name "11-deoxycortisol" is an example of a derived name that uses cortisol as a parent structure without an oxygen atom (hence "deoxy") attached to position 11 (as a part of a hydroxy group). The numbering of positions of carbon atoms in the steroid nucleus is set in a template found in the Nomenclature of Steroids that is used regardless of whether an atom is present in the steroid in question. Unsaturated carbons (generally, ones that are part of a double bond) in the steroid nucleus are indicated by changing -ane to -ene. This change was traditionally done in the parent name, adding a prefix to denote the position, with or without Δ (Greek capital delta) which designates unsaturation, for example, 4-pregnene-11β,17α-diol-3,20-dione (also Δ4-pregnene-11β,17α-diol-3,20-dione) or 4-androstene-3,11,17-trione (also Δ4-androstene-3,11,17-trione).
This remained Knoxville's style of government until the early 20th century, though the city's charter was amended in 1838 to allow for popular election of mayor as well. In January 1816, Knoxville's newly elected Board of Aldermen chose Judge Thomas Emmerson (1773–1837) as the city's first mayor. With the exceptions of the years 1802, 1807, 1811 and 1812, Knoxville remained the capital of Tennessee until 1817 when the state legislature was moved to Murfreesboro.
Sources: en.wikipedia.org
Legality depends on the country and the intended use. In many places it is not approved as a medicine and may be sold only as a research chemical. Importation or possession can be restricted, and sports organizations prohibit it.
Anti-doping laboratories typically use LC-MS/MS to detect SR9009 or its metabolites in urine or blood. The exact assay depends on the laboratory and the testing program. Detection can be challenging because the compound may be rapidly metabolized and present at low levels.
Stenabolic is an informal nickname used in online fitness and research-chemical markets, not an official drug name. It likely references reported effects on endurance in rodent studies. The nickname does not imply approval or proven human benefit.
Liquid chromatography–mass spectrometry is common for identity and purity checks. High-performance liquid chromatography with ultraviolet detection can also be used. Both methods require a suitable reference standard.