LC-MS/MS raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-06-18. Anything still debated is marked as such rather than presented as settled.
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.
Regulatory agencies have not approved SR9009 for human therapeutic use. It is typically sold as a research chemical with labels stating that it is not for human consumption. The World Anti-Doping Agency prohibits the substance in sport, generally under the category of non-approved substances. Customs and national laws may restrict importation, sale, or possession. Product quality and legal status can vary by country and vendor, and therapeutic claims are not permitted in regulated advertising because the compound lacks approval.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic REV-ERB agonist | Small-molecule nuclear receptor ligand |
| Appearance | Off-white to pale yellow solid | Typical for research-grade powder |
| Solubility class | Soluble in DMSO; low water solubility | Common stock solutions use organic solvent |
| Typical stock solvent | Dimethyl sulfoxide | Used for laboratory assays |
| Common analytical method | HPLC with UV or mass detection | Used for identity and purity checks |
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.
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.
Mammals serve a major role in science as experimental animals, both in fundamental biological research, such as in genetics, and in the development of new medicines, which must be tested exhaustively to demonstrate their safety. Millions of mammals, especially mice and rats, are used in experiments each year. A knockout mouse is a genetically modified mouse with an inactivated gene, replaced or disrupted with an artificial piece of DNA. They enable the study of sequenced genes whose functions are unknown. A small percentage of the mammals are non-human primates, used in research for their similarity to humans. Despite the benefits domesticated mammals had for human development, humans have an increasingly detrimental effect on wild mammals across the world. It has been estimated that the mass of all wild mammals has declined to only 4% of all mammals, with 96% of mammals being humans and their livestock now (see figure). In fact, terrestrial wild mammals make up only 2% of all mammals.
An analysis of clinical trials by the FDA statisticians showed the incidence of suicidal behaviour among the adults on venlafaxine to be not significantly different from fluoxetine or placebo. Venlafaxine is contraindicated in children, adolescents, and young adults. In children and adolescents with depression, venlafaxine increases the risk of suicidal thoughts or attempts.
Peukert rejected both viewpoints, instead arguing for seeing Nazi Germany as the product of the "crisis of classical modernity". One of the central objections to the "normality" thesis promoted by Eley and Blackbourn has been if Germany was such a "normal" and "modern" nation, how does one explain the Holocaust? Though Peukert rejected the Sonderweg thesis, he criticized Eley and Blackbourn for associating modernity with "progress", and argued for a "skeptical de-coupling of modernity and progress". Peukert argued that historians must: "raise questions about the pathological and seismic fractures within modernity itself, and about the implicit destructive tendencies of modern industrial class society, which National Socialism made explicit and which elevated it into mass destruction...This approach is supported by a wide variety of debates that have gone within the social sciences, using such notions as 'social disciplining' (Foucault), the pathological consequences of the civilizing progress (Elias), or the colonisation of the Lebenswelten (Habermas). Peukert often wrote on the social and cultural history of the Weimar Republic whose problems he saw as more severe examples of the problems of modernity.
Ultrasound is routinely used in the evaluation of cirrhosis. It may show a small and shrunken liver in advanced disease. On ultrasound, there is increased echogenicity with irregular appearing areas. Other suggestive findings are an enlarged caudate lobe, liver surface nodularity widening of the fissures and enlargement of the spleen. An enlarged spleen, which normally measures less than 11–12 cm (4.3–4.7 in) in adults, may suggest underlying portal hypertension. Ultrasound may also screen for hepatocellular carcinoma and portal hypertension. This is done by assessing flow in the hepatic vein. An increased portal vein pulsatility may be seen. However, this may be a sign of elevated right atrial pressure. Portal vein pulsatility is usually measured by a pulsatility index (PI). A number above a certain value indicates cirrhosis (see table below).
Sources: en.wikipedia.org
5 July Results of the 2024 United Kingdom general election: Sir Keir Starmer becomes the prime minister of the United Kingdom, following a landslide victory for Labour in the general election. The Conservatives are reduced to just 121 seats, the lowest number of MPs in their 190-year history. Among the high-profile losses are former Prime Minister Liz Truss, former cabinet minister Sir Jacob Rees-Mogg, Commons leader Penny Mordaunt, and Defence Secretary Grant Shapps. The Liberal Democrats, led by Sir Ed Davey, achieve their best ever result with 71 seats. The Green Party achieve their best ever result, quadrupling their number of seats to four. Reform UK gain their first seats in Parliament, which includes party leader Nigel Farage taking the constituency of Clacton. The SNP suffers heavy losses, going from 48 seats to just nine. Starmer ministry: Starmer appoints his first cabinet. Angela Rayner becomes Deputy Prime Minister Rachel Reeves becomes Chancellor of the Exchequer David Lammy becomes Foreign Secretary Yvette Cooper becomes Home Secretary John Healey becomes Defence Secretary 6 July Starmer holds his first press conference as prime minister, during which he confirms that the Rwanda deportation scheme is "dead and buried". Euro 2024: After finishing 1–1 at the end of extra time, England beat Switzerland 5–3 on penalties, taking them through to the semi-finals. Andy Murray's Wimbledon career comes to an end after Emma Raducanu withdraws from the mixed doubles.
== Contraindications == Ioxaglic acid is contraindicated in people with hyperthyreosis because of the drug's iodine content. It must not be used for myelography (spinal cord imaging), for hysterosalpingography in women who are pregnant or have an acute inflammation in the pelvic region, or for arthrography if the joint is infected.
== History == GCLS was established in Geneva in 2024 with a focus on formal education in longevity science, an interdisciplinary field drawing on ageing biology, preventive medicine, public health and related disciplines. Dominik Thor has served as president of the institution. Luiza Spiru, a physician and professor whose work includes gerontology, geriatrics and longevity medicine, has been involved in its academic programmes. The institution subsequently expanded its postgraduate and professional education and developed international scientific activities. In February 2025, GCLS partnered with Dubai Science Park to hold a Longevity Science Semester Symposium in Dubai. Dubai Science Park reported that the two-day meeting brought together participants from healthcare, life sciences, academic and public-sector organizations. In 2026, GCLS announced an academic partnership with Ovidius University of Constanța for a research doctorate in medicine with a specialization in longevity sciences. Ovidius University is identified as the degree-awarding institution, while GCLS serves as the international academic partner. GCLS provides postgraduate and professional education in longevity science and longevity medicine. Its portfolio includes a master's-level programme in longevity science, continuing medical education and professional training for physicians, and postgraduate study in peptide therapeutics.
initiation factor (IF) Any of various proteins which bind to the small or large subunit of ribosomes during the initiation of translation and thereby play roles in regulating when and how protein synthesis occurs. Initiation factors are essential for assembly of the initiation complex and for charged transfer RNAs to properly associate with the ribosome and the messenger RNA. They are frequent targets of activators and repressors which can respectively increase or decrease the rate of translation. Though their functions are largely conserved, they are distinguished by the taxonomic domain in which they occur: bacterial initiation factors (IFs), archaeal initiation factors (aIFs), and eukaryotic initiation factors (eIFs).
At cytoplasmic conditions, where the ADP/ATP ratio is 10 orders of magnitude from equilibrium, the ΔG is around −57 kJ/mol. Along with pH, the free energy change of ATP hydrolysis is also associated with Mg2+ concentration, from ΔG°' = −35.7 kJ/mol at a Mg2+ concentration of zero, to ΔG°' = −31 kJ/mol at [Mg2+] = 5 mM. Higher concentrations of Mg2+ decrease free energy released in the reaction due to binding of Mg2+ ions to negatively charged oxygen atoms of ATP at pH 7.
Sources: en.wikipedia.org
When the text was disclosed in the British press, it generated a storm of anti-German feeling. In the baggage of the raiding column, to the embarrassment of Britain, the Boers found telegrams from Rhodes and other plotters in Johannesburg. Chamberlain had approved Rhodes' plans to send armed assistance in the case of a Johannesburg uprising, but he quickly moved to condemn the raid. Rhodes was censured at the Cape and London parliamentary inquiries, and forced to resign as Prime Minister and Chairman of the British South Africa Company. The Boer government handed their prisoners over to the British for trial. Jameson was tried in England, where the press and London society, inflamed by anti-Boer and anti-German feeling and in a frenzy of jingoism, treated him as a hero. Although sentenced to 15 months imprisonment, Jameson was rewarded by being named Prime Minister of the Cape Colony (1904–08) and ultimately anointed as one of the founders of the Union of South Africa. For conspiring with Jameson, the uitlander members of the Reform Committee (Transvaal) were tried in the Transvaal courts and found guilty of treason. The four leaders were sentenced to death, but this was commuted to 15 years' imprisonment. In 1896, the other members of the committee were released on payment of £2,000 in fines, all paid by Rhodes. One Reform Committee member, Frederick Gray, committed suicide while in Pretoria jail. His death was a factor in softening the Transvaal government's attitude to the surviving prisoners. Jan C. Smuts wrote, in 1906:
The disorder prediction category is a part of biannual CASP experiment that is designed to test methods according accuracy in finding regions with missing 3D structure (marked in PDB files as REMARK465, missing electron densities in X-ray structures). Disorder prediction can be more complicated for de novo-emerged and orphan proteins, which often lack detectable homologs and are generally shorter than "classical" proteins, reducing the reliability of predictors trained largely on conserved, globular proteins. Comparative benchmarks further show that structure/disorder predictors behave differently on de novo and random proteins than on conserved proteins, including different relationships between predicted disorder and confidence scores of 3D structure predictors, such as AlphaFold and ESMfold.
Phenol derivatives There are a number of glucosides found in natural phenols and polyphenols, as, for example, in the flavonoids chemical family. Arbutin, which occurs in bearberry along with methyl arbutin, hydrolyses to hydroquinone and glucose. Pharmacologically it acts as a urinary antiseptic and diuretic; Salicin, also termed Saligenin and glucose occurs in the willow. The enzymes ptyalin and emulsin convert it into glucose and saligenin, ortho-oxybenzylalcohol. Oxidation gives the aldehyde helicin.
=== Birds === Close to ninety percent of known avian species are monogamous, compared to five percent of known mammalian species. The majority of monogamous avians form long-term pair bonds which typically result in seasonal mating: these species breed with a single partner, raise their young, and then pair up with a new mate to repeat the cycle during the next season. Some avians such as swans, bald eagles, California condors, and the Atlantic Puffin are not only monogamous, but also form lifelong pair bonds. When discussing the social life of the bank swallow, Lipton and Barash state:
Salutaridinol can be converted in two reaction steps to the morphine precursor thebaine. The first step is an esterification of the hydroxyl group previously reduced in the conversion of salutaridine to salutaridinol with acetyl-CoA. This step is mediated by the enzyme salutaridinol 7-O-acetyltransferase. The second step is a ring closure achieved by a nucleophilic attack of the phenol group on the dienol system to generate an oxide bridge and kick out an acetate leaving group, giving thebaine. This second step does not require an enzyme. Thebaine can then be converted to morphine through two slightly different biosynthetic routes, one of which makes use of the fourth enzyme codeinone reductase.
Sources: en.wikipedia.org
SR9009 is a synthetic research compound that acts on REV-ERB nuclear receptors. It is not approved for human use and is sold only as a research chemical. Its effects have been studied mainly in cells and rodents.
It binds REV-ERB alpha and REV-ERB beta and changes the expression of genes tied to metabolism and circadian rhythm. These changes can affect mitochondria and energy use in animal models. The exact chain from receptor binding to physiological outcome is still being mapped.
No reliable human trials show that SR9009 improves athletic performance. Some rodent studies report endurance changes, but these results are not proof of human benefit. Its use in sport is prohibited, and quality and safety data are lacking.
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.