This is a working overview of anti-doping, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-03-15 and is reviewed periodically as new material appears.
Detection of SR9009 in biological samples usually employs liquid chromatography coupled with tandem mass spectrometry. This method can identify the parent compound and sometimes metabolites in urine or blood. Because exposure can be low and clearance may be rapid, sample timing and limits of detection matter. Laboratories validate assays for sensitivity and specificity. Results are interpreted alongside chain-of-custody and quality-control records. Urine is the common matrix for anti-doping analysis, while blood may be used in research settings.
Handling recommendations for SR9009 in a laboratory setting include storing the solid at low temperature, protected from light and moisture. The compound is often dissolved in dimethyl sulfoxide or ethanol for experiments. Solutions should be prepared with appropriate personal protective equipment and disposed of according to local rules. Stability data for long-term storage are limited, so stock solutions are typically kept cold and used within defined periods. Records of preparation date and concentration support reproducibility.
SR9009 is not approved as a medicine by major regulatory agencies. It is commonly sold as a research chemical, a category that may fall outside customary drug approval and quality rules. In sports, the World Anti-Doping Agency lists SR9009 as a prohibited substance. Athletes who use it can face sanctions if it is detected in a sample. Legal status varies by country, and importation may be restricted. Enforcement practices differ across borders.
SR9009 is a synthetic small molecule developed as a REV-ERB agonist. It binds to REV-ERBα and REV-ERBβ, nuclear receptors that help regulate circadian rhythms and metabolic gene expression. In cell and animal studies, the compound alters lipid and glucose handling and influences skeletal muscle oxidative capacity. Its exact effects in humans remain largely uncharacterized because controlled clinical trials have not been reported. The molecule is frequently described in preclinical literature as a metabolic modulator.
Research interest in SR9009 grew from studies showing improved running endurance in mice after short treatment periods. Those experiments linked the compound to increased mitochondrial content and fatty acid oxidation in muscle, but the findings come from animal models and specific dosing schedules. Independent replication has been limited, and the pathways connecting REV-ERB activation to exercise performance are still being mapped. Whether similar responses occur in humans is an open question.
SR9009 is often grouped with compounds studied for circadian and metabolic regulation rather than with classical anabolic steroids. Its interactions with nuclear receptors differ from those of androgen receptor ligands, and its proposed mechanisms involve transcriptional control rather than direct hormone signaling. Some sources classify it as a metabolic modulator because of observed effects on energy utilization. The distinction matters for regulation and for interpreting research results across different compound classes.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Not approved as a medicine in major jurisdictions | Sold as a research chemical; legal status varies |
| Anti-doping status | Prohibited by the World Anti-Doping Agency | Listed under non-approved substances or related category |
| Typical analytical method | LC-MS/MS | Used for detection and confirmation in biological samples |
| Storage temperature | −20 °C or lower for solid | Desiccated and protected from light |
| Common solution solvents | DMSO; ethanol | Aqueous solubility is limited |
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.
SR9009 binds REV-ERB receptors and alters their repressive activity on target genes. This action can change transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. In rodent studies, treated animals have shown changes in muscle oxidative capacity and exercise performance, though effects vary by dose, duration, and model. The precise molecular steps connecting receptor binding to whole-body outcomes are still an active area of investigation. Findings in animals do not automatically translate to humans.
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.
=== Peptidoglycan binding and hydrolysis === PGLYRP2 is an enzyme (EC 3.5.1.28), N-acetylmuramoyl-L-alanine amidase, that binds and hydrolyzes bacterial cell wall peptidoglycan. Peptidoglycan is the main component of bacterial cell wall and is a polymer of β(1–4)-linked N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc) with MurNAc-attached short peptides, typically composed of alternating L and D amino acids, that cross-link the adjacent polysaccharide chains. PGLYRP2 hydrolyzes the amide bond between the MurNAc and L-Ala, the first amino acid in the stem peptide. This hydrolysis separates the crosslinking peptides from the polysaccharide chains and solubilizes cross-linked bacterial peptidoglycan into uncross-linked polysaccharide chains. The minimal peptidoglycan fragment hydrolyzed by PGLYRP2 is MurNAc-tripeptide. The peptidoglycan-binding site, which is also the amidase catalytic domain, is located in the C-terminal PGRP domain. This PGRP domain is sufficient for the enzymatic activity of PGLYRP2, although this activity of the isolated C-terminal fragment is diminished compared with the entire PGLYRP2 molecule. Zn2+ and Zn2+-binding amino acids (His411, Tyr447, and Cys530 in human PGLYRP2) are required for the amidase activity. Cys419 in human PGLYRP2, which is broadly conserved in invertebrate and vertebrate PRGPs, forms a disulfide bond with Cys425 (in human PGLYRP2) and is required for the amidase activity, as this disulfide bond is essential for the structural integrity of the PGRP domain.
dipole The electric or magnetic separation of electric charge into a pair of charges of equal magnitude but opposite sign, one positively charged and one negatively charged, separated by some typically small distance.
MiaB introduces a methylthio group to the isopentenylated A37 derivatives in the tRNA of S. Typhimurium and E. coli by utilizing one SAM molecule to generate 5'-dAdo radical to activate the substrate and a second SAM to donate a sulfur atom to the substrate. RimO is responsible for post-translational modification of Asp88 of the ribosomal protein S12 in E. coli. The crystal structure sheds light on the mechanistic action of RimO. The enzyme catalyzes pentasulfide bridge formation linking two Fe-S clusters to allow for sulfur insertion to the substrate. eMtaB is the designated methylthiotransferase in eukaryotic and archaeal cells. eMtaB catalyzes the methylthiolation of tRNA at position 37 on N6-threonylcarbamoyladenosine. A bacterial homologue of eMtaB, YqeV has been reported and suggested to function similarly to MiaB and RimO.
Sources: en.wikipedia.org
A bulk material should have constant physical properties regardless of its size, but at the nano-scale this is often not the case. Size-dependent properties are observed such as quantum confinement in semiconductor particles, surface plasmon resonance in some metal particles, and superparamagnetism in magnetic materials. Nanoparticles exhibit a number of special properties relative to bulk material. For example, the bending of bulk copper (wire, ribbon, etc.) occurs with movement of copper atoms/clusters at about the 50 nm scale. Copper nanoparticles smaller than 50 nm are considered super hard materials that do not exhibit the same malleability and ductility as bulk copper. The change in properties is not always desirable. Ferroelectric materials smaller than 10 nm can switch their polarization direction using room temperature thermal energy, thus making them useless for memory storage. Suspensions of nanoparticles are possible because the interaction of the particle surface with the solvent is strong enough to overcome differences in density, which usually result in a material either sinking or floating in a liquid. Nanoparticles often have unexpected visual properties because they are small enough to confine their electrons and produce quantum effects. For example, gold nanoparticles appear deep red to black in solution. The often very high surface area to volume ratio of nanoparticles provides a tremendous driving force for diffusion, especially at elevated temperatures. Sintering is possible at lower temperatures and over shorter durations than for larger particles.
The 10th pro-Palestinian march to be staged in central London since the beginning of the Israel–Gaza conflict takes place, with tens of thousands of protestors calling for an immediate ceasefire. A man is arrested after a car crashes into the gates of Buckingham Palace in the early hours of the morning. 10 March Kensington Palace releases the first official photograph of the Princess of Wales since she underwent abdominal surgery in January. However, hours later, four international photo agencies – Associated Press, Reuters, Getty Images and AFP – withdraw the photo from their services over concerns it has been photoshopped or AI generated, after an "inconsistency in alignment of Princess Charlotte's left hand" is noted along with various other signs of digital manipulation. Kensington Palace declines to comment on the photo, as speculation intensifies over why an altered photo has been published. The Mail on Sunday serialises A Very Private School, Earl Spencer's memoirs of his schooldays at Maidwell Hall during the 1970s, in which he alleges that he was sexually abused by a female member of staff while a boarder at the school. Spencer also alleges the school's headmaster during his time there took sexual pleasure in beating the boys. In response, the school says it has referred the allegations to a "local authority designated officer". 11 March Ashfield MP Lee Anderson defects from the Conservatives to Reform UK, becoming the party's first sitting Member of Parliament.
It has a unicameral national legislature known as the Assembly of the Republic (Assembleia da República). Portugal is divided into seven mainland regions and two autonomous overseas regions, though it remains a highly centralised country. A developed country, Portugal has an advanced economy that chiefly relies upon services, industry, and tourism. Shaped by the various civilisations that have inhabited its territory, such as the Carthaginians and the Romans, Portugal developed a culture with a worldwide influence. This allowed Portuguese to become the world's fifth-most spoken native language, with more than 250 million native speakers. With a stable foreign policy shaped by its colonial and diplomatic history and location, Portugal is a member of multiple international organisations and forums.
Sources: en.wikipedia.org
Members of this family are found in birds, fish, reptiles and amphibians (mesotocin, isotocin, valitocin, glumitocin, aspargtocin, vasotocin, seritocin, asvatocin, phasvatocin), in worms (annetocin, nematocin), octopuses (cephalotocin, octopressin), insects (locupressin, inotocin) and in molluscs (conopressins G and S). Animals that lack a hormone from this family include fruit flies, and at least some mosquitos, silkworms, and honeybees.
=== Archives === Lt. John T. Alderson collection of Japan photographs Archived September 4, 2015, at the Wayback Machine. circa 1890s. 40 photographic prints (1 box) : hand colored; sizes vary. At the University of Washington Libraries, Special Collections.
Quantum wires, which confine electrons or holes in two spatial dimensions and allow free propagation in the third. Quantum wells, which confine electrons or holes in one dimension and allow free propagation in two dimensions.
Sources: en.wikipedia.org
Its legal status depends on the country and intended use. It is not an approved medicine in major jurisdictions. In sport, it is prohibited by anti-doping rules.
Laboratories typically use LC-MS/MS to detect SR9009 and related compounds in urine or blood. The method is sensitive but depends on sample collection timing. Confirmatory analysis follows quality-control procedures.
Solid material is generally kept cold, dry, and protected from light. Solutions are often stored in sealed containers at low temperature. Stability beyond recommended periods is not well documented.
It is a synthetic REV-ERB agonist used mainly in preclinical research. It is not an approved medicine for human use.