This is a working overview of circadian rhythm, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-10-17. Anything still debated is marked as such rather than presented as settled.
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.
Stability depends on physical form, temperature, light exposure, and solvent. Solid SR9009 is generally stored cold and dry, with protection from light to limit degradation. Dimethyl sulfoxide stocks are common for laboratory work, but repeated freeze-thaw cycles can reduce compound integrity. Aqueous solutions may be less stable than organic stocks, and the ethyl ester in the structure can be susceptible to hydrolysis under certain conditions. Researchers typically validate storage conditions and recheck purity before quantitative experiments, especially when using archived material.
Regulatory treatment of SR9009 varies by country and region. It is not approved as a pharmaceutical, and several jurisdictions restrict its sale for human consumption. Some authorities classify it as a research chemical, a prescription-only substance, or a prohibited performance-enhancing agent in sport. Purchasers may encounter certificates of analysis, but these documents do not guarantee identity, purity, or legality. In research settings, institutional safety reviews and controlled procurement help ensure that materials are handled under appropriate oversight. The absence of harmonized rules means that legal status can change and requires verification.
Analytical identification of SR9009 typically relies on liquid chromatography coupled with tandem mass spectrometry. In biological samples, researchers first separate the compound from matrix components using protein precipitation, liquid-liquid extraction, or solid-phase extraction. High-performance liquid chromatography with ultraviolet detection and nuclear magnetic resonance spectroscopy can support structural confirmation of reference materials. Because SR9009 is a small, relatively lipophilic molecule, reverse-phase columns and acidic mobile phases are common. Laboratories often include isotope-labeled internal standards to improve quantification and to correct for ion suppression.
| 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 |
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 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 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.
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.
In the drug discovery process of a 5-HT2C agonist, a pharmacophore module has been used to discover novel 5-HT2C receptor ligands. The pharmacophore has four features; one aromatic ring, two hydrophobic features and one positive ionizable feature. Figure 4 shows an example of a compound that fits the agonist pharmacophore perfectly. The nitrogen atom of piperazine fits the positive ionizable feature, the benzofuran part fits the aromatic ring and one hydrophobic, and the trifluoromethane part fits another hydrophobic feature of the pharmacophore.
=== Tizard committee === The need to research better forms of air defense prompted Harry Wimperis to press for the formation of a study group to consider new concepts. Lord Londonderry, then Secretary of State for Air, approved the formation of the Committee for the Scientific Survey of Air Defence in November 1934, asking Henry Tizard to chair the group, which thus became better known to history as the Tizard Committee. When Wimperis sought an expert in radio to help judge the death-ray concept, he was naturally directed to Watt. He wrote to Watt "on the practicability of proposals of the type colloquially called 'death ray'". The two met on 18 January 1935, and Watt promised to look into the matter. Watt turned to Wilkins for help but wanted to keep the underlying question a secret. He asked Wilkins to calculate what sort of radio energy would be needed to raise the temperature of 8 imperial pints (4.5 L) of water at a distance of 5 kilometres (3.1 mi) from 98 to 105 °F (37 to 41 °C). To Watt's bemusement, Wilkins immediately surmised this was a question about a death ray. He made a number of back-of-the-envelope calculations demonstrating the amount of energy needed would be impossible given the state of the art in electronics. According to R. V.
Varying concentrations of Asparagopsis taxiformis were mixed with Rhodes grass and examined using standardised in vitro culture methods. Five dosages were tested ranging from 0.5% to 10% of dietary composition. The optimum concentration was determined to be 2%, as it virtually eliminated methane production and reduced the volume of total gases produced by 30% without affecting fermentation efficiency. Dosages under 5% had no effect on volatile fatty acid concentrations, which is the primary source of energy resulting from digestion. In 2016, live tests were performed on sheep at the CSIRO Centre for Environment and Life Sciences in Floreat, Western Australia. 29 merino sheep were fed one of five dosage levels (0%, 0.5%, 1%, 2% or 3% dietary intake) and monitored over a 72-day feeding period. In dosages of 2%, methane emission reductions of up to 85% were recorded when compared to control sheep. The sheep given dosages of 0.5% recorded at least a 50% reduction in methane emissions. No evidence of microbial adaptation occurred over the 72 days of testing and methane was continually and consistently mitigated. Tissue examination showed no adverse effects on the overall health of the sheep. In 2017, live tests over 90 days were performed on cattle at the CSIRO Lansdown facility in Queensland. 28 Brahman-Angus steers were separated into four groups and given varying dosages of dried Asparagopsis in a simulated feedlot. Concentration levels for each group were 0% (control), 0.5% (low), 1% (medium) and 2% (high) intake of Asparagopsis.
== Initiatives around the globe == In the United States in 2006, JDRF (formerly the Juvenile Diabetes Research Foundation) launched a multi-year initiative to help accelerate the development, regulatory approval, and acceptance of continuous glucose monitoring and artificial pancreas technology. Grassroots efforts to create and commercialize a fully automated artificial pancreas system have also arisen directly from patient advocates and the diabetes community. In April 2024, the NHS announced it would, over the next five years, offer use of a Hybrid Closed Loop system to Type 1 diabetes patients in England.
Sources: en.wikipedia.org
As he neared death after suffering strokes, Lenin's Testament of December 1922 named Trotsky and Stalin as the most able men in the Central Committee, but he harshly criticised them. Lenin said that Stalin should be removed from being the General Secretary of the party and that he be replaced with "some other person who is superior to Stalin only in one respect, namely, in being more tolerant, more loyal, more polite, and more attentive to comrades." Upon his death on 21 January 1924, Lenin's political testament was read aloud to the Central Committee, who chose to ignore Lenin's ordered removal of Stalin as General Secretary because enough members believed Stalin had been politically rehabilitated in 1923. Consequent to personally spiteful disputes about the praxis of Leninism, the October Revolution veterans Lev Kamenev and Grigory Zinoviev said that the true threat to the ideological integrity of the party was Trotsky, who was a personally charismatic political leader as well as the commanding officer of the Red Army in the Russian Civil War and revolutionary partner of Lenin. To thwart Trotsky's likely election to head the party, Stalin, Kamenev and Zinoviev formed a troika that featured Stalin as General Secretary, the de facto centre of power in the party and the country. The direction of the party was decided in confrontations of politics and personality between Stalin's troika and Trotsky over which Marxist policy to pursue, either Trotsky's policy of permanent revolution or Stalin's policy of socialism in one country.
=== Ovulation === NGF is abundant in seminal plasma. Recent studies have found that it induces ovulation in some mammals e.g. "induced" ovulators, such as llamas. Surprisingly, research showed that these induced animals will also ovulate when semen from on-schedule or "spontaneous" ovulators, such as cattle is used. Its significance in humans is unknown. It was previously dubbed ovulation-inducing factor (OIF) in semen before it was identified as beta-NGF in 2012.
Mirodenafil is a PDE5 inhibitor used to treat erectile dysfunction. Developed by SK Chemicals Life Science, mirodenafil is marketed in Korea under the brand name Mvix, offered both as tablets (50 mg and 100 mg) and as orally dissolving films (50 mg). Despite several clinical trials having been conducted, mirodenafil has not been approved for use in the United States by the US Food and Drug Administration.
Sources: en.wikipedia.org
The fungus is highly toxic, and is responsible for the majority of fatal mushroom poisonings worldwide. Its biochemistry has been researched intensively for decades, and 30 grams (1.1 ounces), or half a cap, of this mushroom is estimated to be enough to kill a human. On average, one person dies a year in North America from death cap ingestion. The toxins of the death cap mushrooms primarily target the liver, but other organs, such as the kidneys, are also affected. Symptoms of death cap mushroom toxicity usually occur 6 to 12 hours after ingestion. Symptoms of ingestion of the death cap mushroom may include nausea and vomiting, which is then followed by jaundice, seizures, and coma, which will lead to death. The mortality rate of ingestion of the death cap mushroom is believed to be around 10–30%. Some authorities strongly advise against putting suspected death caps in the same basket with fungi collected for the table and to avoid even touching them. Furthermore, the toxicity is not reduced by cooking, freezing, or drying. Poisoning incidents usually result from errors in identification. Recent cases highlight the issue of the similarity of A. phalloides to the edible paddy straw mushroom (Volvariella volvacea), with East and Southeast Asian immigrants in Australia and the West Coast of the U.S. falling victim. In an episode in Oregon, four members of a Korean family required liver transplants. Many North American incidents of death cap poisoning have occurred among Laotian and Hmong immigrants, since it is easily confused with A.
== Medical uses == Protriptyline is used primarily to treat depression and to treat the combination of symptoms of anxiety and depression. Like most antidepressants of this chemical and pharmacological class, protriptyline has also been used in limited numbers of patients to treat panic disorder, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, enuresis, eating disorders such as bulimia nervosa, cocaine dependency, and the depressive phase of bipolar disorder (manic-depressive) disorder. It has also been used to support smoking cessation programs. Protriptyline is available as 5 mg and 10 mg tablets. Doses range from 15 to 40 mg per day and can be taken in one daily dose or divided into up to four doses daily. Some people with severe depression may require up to 60 mg per day. In adolescents and people over age 60, therapy should be initiated at a dose of 5 mg three times a day and increased under the supervision of a physician as needed. Patients over age 60 who are taking daily doses of 20 mg or more should be closely monitored for side effects such as rapid heart rate and urinary retention. Like all TCAs, protriptyline should be used cautiously and with close physician supervision. This is especially so for persons with glaucoma, especially angle-closure glaucoma (the most severe form) or urinary retention, for men with benign prostatic hyperplasia (enlarged prostate gland), and for the elderly.
Anne S. Ulrich (born December 31, 1966) is a German chemist. She is the director of the Institute of Biological Interfaces (IBG-2) and Chair of Biochemistry at the Karlsruhe Institute of Technology. She studied chemistry at the University of Oxford - continued her doctoral work in the laboratory of Anthony Watts - held subsequent research positions as an EMBO-Fellow with Hartmut Oschkinat at the European Molecular Biology Laboratory in Heidelberg and as a Liebig-Fellow with Felix Wieland at the University of Heidelberg - became Associate Professor at the University of Jena - until she moved her group in 2002 to the Karlsruhe Institute of Technology. Her research focuses on the structural and functional analysis of biomembranes by solid state NMR. The main systems of interest are:
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.
The most common approach is liquid chromatography-tandem mass spectrometry, often after extraction from blood, urine, or tissue. Ultraviolet detection and nuclear magnetic resonance spectroscopy are used mainly for reference material characterization. Isotope-labeled internal standards improve accuracy.