reference standard raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-03-04 and is reviewed periodically as new material appears.
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.
In rodent studies, SR9009 has been reported to increase mitochondrial content in skeletal muscle and improve exercise endurance under some conditions. These findings led to popular descriptions such as an exercise mimetic, although that term oversimplifies the biology. Effects vary by dose, timing, tissue, and model. The compound's influence on circadian pathways means that time of administration can matter in experiments. Whether similar metabolic changes occur in humans remains largely unexplored in controlled published trials.
Pharmacokinetic data for SR9009 are limited in published literature. Some reports indicate low oral bioavailability and rapid clearance in animals, which complicates interpretation of exposure and effect. Researchers often use injected routes in preclinical work to achieve measurable systemic levels. Analytical studies rely on mass spectrometry to detect the parent compound and its metabolites. Questions about tissue distribution, active metabolites, and long-term consequences remain open. Species differences in metabolism can affect observed half-life and target engagement.
| 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 |
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.
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.
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.
Detection in biological samples can be complicated by rapid metabolism and low circulating concentrations. Some studies report phase I and phase II metabolites, and analytical methods may need to target those species in addition to the parent compound. Immunoassays are not broadly available, so mass spectrometry remains the main confirmatory approach. For anti-doping testing, laboratories look for SR9009 and its metabolites using validated LC-MS methods. Open questions include how long metabolites remain detectable and how different routes of administration alter detection windows.
In laboratory settings, SR9009 is typically characterized by liquid chromatography–mass spectrometry (LC-MS) or high-performance liquid chromatography with ultraviolet detection (HPLC-UV). These methods can confirm identity and estimate purity, but they require reference standards for accurate quantification. Because SR9009 is not a licensed pharmaceutical, no harmonized pharmacopeial monograph exists. Laboratories often validate in-house methods for matrices such as plasma, urine, or cell culture media. Sample preparation may involve protein precipitation or liquid-liquid extraction before analysis.
Although leptin reduces appetite as a circulating signal, obese individuals generally exhibit a higher circulating concentration of leptin than normal weight individuals due to their higher percentage body fat. These people show resistance to leptin, similar to resistance of insulin in type 2 diabetes, with the elevated levels failing to control hunger and modulate their weight. A number of explanations have been proposed to explain this. An important contributor to leptin resistance is changes to leptin receptor signalling, particularly in the arcuate nucleus. However, deficiency of, or major changes to, the leptin receptor itself are not thought to be a major cause. Triglycerides crossing the blood brain barrier (BBB) can induce leptin and insulin resistance in the hypothalamus. Triglycerides can also impair leptin transport across the BBB. Studies on leptin cerebrospinal fluid (CSF) levels provide evidence for the reduction in leptin crossing the BBB and reaching obesity-relevant targets, such as the hypothalamus, in obese people. In humans it has been observed that the ratio of leptin in the CSF compared to the blood is lower in obese people than in people of a normal weight. The reason for this may be high levels of triglycerides affecting the transport of leptin across the BBB or due to the leptin transporter becoming saturated. Although deficits in the transfer of leptin from the plasma to the CSF is seen in obese people, they are still found to have 30% more leptin in their CSF than lean individuals. These higher CSF levels fail to prevent their obesity.
Existential risk researchers analyze risks that could lead to human extinction or civilizational collapse, and look for ways to build resilience against them. Relevant research centers include the Cambridge Center for the Study of Existential Risk and the Stanford Existential Risk Initiative. Future technologies may contribute to the risks of artificial general intelligence, biological warfare, nuclear warfare, nanotechnology, anthropogenic climate change, global warming, or stable global totalitarianism, though technologies may also help to mitigate asteroid impacts and gamma-ray bursts. In 2019, philosopher Nick Bostrom introduced the notion of a vulnerable world, "one in which there is some level of technological development at which civilization almost certainly gets devastated by default", citing the risks of a pandemic caused by bioterrorists, or an arms race triggered by the development of novel armaments and the loss of mutual assured destruction. He invites policymakers to question the assumptions that technological progress is always beneficial, that scientific openness is always preferable, or that they can afford to wait until a dangerous technology has been invented before they prepare mitigations.
Fifteen minutes later Faith 7 landed just four miles (6 km) from the prime recovery ship, the carrier USS Kearsarge. This was the most accurate landing to date, despite the lack of automatic controls. Faith 7 landed 70 nautical miles (130 km) southeast of Midway Island, in the Pacific Ocean. This would be near 27°30′N 176°15′W. Splashdown was at 34 hours 19 minutes 49 seconds after liftoff. The spacecraft tipped over in the water momentarily, then righted itself. Helicopters dropped rescue swimmers and relayed Cooper's request of an Air Force officer for permission to be hoisted aboard the Navy's carrier. Permission was granted. Forty minutes later the explosive hatch blew open on the deck of Kearsarge. Cooper stepped out of Faith 7 to a warm greeting.
A study that compares two groups of people: those with the disease or condition under study (cases) and a very similar group of people who do not have the disease or condition (controls). Researchers study the medical and lifestyle histories of the people in each group to learn what factors may be associated with the disease or condition. For example, one group may have been exposed to a particular substance that the other was not. Also called a retrospective study. (NCI) Clinical
Sources: en.wikipedia.org
The production was noted (by Nehad Selaiha of the weekly Al-Ahram) not only for its unexpected change of plot at the very end but also for its chorus of one hundred who alternated their speech between Arabic and English. The translation used was that of George Theodoridis. US Latina playwright Caridad Svich's 2009 play Wreckage, which premiered at Crowded Fire Theatre in San Francisco, tells the story of Medea from the sons' point of view, in the afterlife. Paperstrangers Performance Group toured a critically acclaimed production of Medea directed by Michael Burke to U.S. Fringe Festivals in 2009 and 2010. Bart Lee's interpretation of Medea, renamed Medea, My Dear, was performed in Surrey and later toured the south of England from 2010 to 2011. Luis Alfaro's re-imagining of Medea, Mojada, world premiered at Victory Gardens Theater in 2013. Theatre Lab's production, by Greek director Anastasia Revi, opened at The Riverside Studios, London, on 5 March 2014. The Hungry Woman: A Mexican Medea by Cherríe Moraga takes elements of Medea and of other works. 14 July – 4 September 2014 London Royal National Theatre staging of Euripides in a new version by Ben Power, starring Helen McCrory as Medea, directed by Carrie Cracknell, music by Will Gregory and Alison Goldfrapp. 25 September – 14 November 2015 London Almeida Theatre a new adaptation by Rachel Cusk, starring Kate Fleetwood as Medea, directed by Rupert Goold. 17 February – 6 March 2016 in Austin at the Long Center for the Performing Arts starring Franchelle Stewart Dorn as Medea and directed by Ann Ciccolella.
Clinafloxacin is an investigational fluoroquinolone antibiotic. Despite its promising antibiotic activity, the clinical development of clinafloxacin has been hampered by its risk for inducing serious side effects.
After a vascular injury occurs, platelets are activated by locally exposed collagen (glycoprotein (GP) VI receptor), locally generated thrombin (PAR1 and PAR4 receptors), platelet-derived thromboxane A2 (TxA2) (TP receptor) and ADP (P2Y1 and P2Y12 receptors) that is either released from damaged cells or secreted from platelet dense granules. The von Willebrand factor (VWF) serves as an essential accessory molecule. In general terms, platelet activation initiated by agonist takes to a signaling cascade that leads to an increase of the cytosolic calcium concentration. Consequently, the integrin αIIbβ3 is activated and the binding to fibrinogen allows the aggregation of platelets to each other. The increase of cytosolic calcium also leads to shape change and TxA2 synthesis, leading to signal amplification.
Creating a CCP involves three steps: initiation, multiplication and mixture. The population then goes into the maintenance phase. A number of lines, generally 7-30, with interesting properties, such as yield or baking quality, are selected and all possible crosses of them are done. If many lines of different genetic background are used, a huge amount of genetic diversity will be present. Seeds from crosses are sown out and harvested separately for a growing season or two until enough seeds are available. All seeds are mixed in equal portions to produce the first CCP generation. The population is grown repeatedly and possibly changes due to natural selection. Each year seeds are saved after harvest, and used as seed for the next growing season. Plants that are successful under the prevailing growing conditions will give more seeds and contribute more to the next generation, compared to less successful plants. Disease will cull susceptible plants and the population will over time become resistant to the common diseases, but only if the initial population has resistance genes present.
2 LuCl3 + 3 Ca → 2 Lu + 3 CaCl2 177Lu is produced by neutron activation of 176Lu or by indirectly by neutron activation of 176Yb followed by beta decay. The 6.693-day half-life allows transport from the production reactor to the point of use without significant loss in activity.
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.
It is a synthetic research compound that activates REV-ERB nuclear receptors. It is not an approved drug or dietary supplement. Most information comes from cell and animal studies.