A practical reference on circadian clock: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
REV-ERB proteins help regulate daily cycles in gene expression, including genes tied to lipid and glucose metabolism. SR9009 binds these receptors and alters their activity in cell and animal experiments. Consequences observed in rodents include changes in skeletal muscle oxidative capacity, blood lipid levels, and exercise performance. The precise chain from receptor occupancy to whole-body effects is still an active area of study. Human responses cannot be assumed from rodent data.
Most published work on SR9009 consists of preclinical studies. It is widely sold as a research chemical, a category that does not imply safety, efficacy, or pharmaceutical-grade quality. Sports anti-doping organizations have listed SR9009 as a prohibited substance, and its presence in an athlete sample can lead to sanctions. Legal status differs by country; in several jurisdictions it is not approved for human consumption and may be treated as an unapproved new drug.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is not a steroid, peptide, or natural hormone. In scientific literature, it appears under the code SR9009 and in non-scientific contexts as Stenabolic. The compound was identified through chemical screening efforts aimed at targeting circadian clock components. Its status remains investigational, and no regulatory agency has approved it as a human medicine.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Common name | SR9009 | Also referred to as Stenabolic in non-scientific contexts. |
| Chemical class | Synthetic small molecule | Not a steroid or peptide hormone. |
| Receptor target | REV-ERBα and REV-ERBβ | Nuclear receptor agonist in preclinical studies. |
| Development status | Investigational | No approved human therapeutic indication. |
| Regulatory attention | Prohibited in sport | Listed by anti-doping authorities. |
Quality control for research materials includes identity confirmation by nuclear magnetic resonance and purity assessment by high-performance liquid chromatography. Mass spectrometry provides molecular weight confirmation and can detect related impurities. Purchasers should request a certificate of analysis that lists lot-specific data. Online products advertised for human use often lack such documentation. Distinguishing legitimate research material from mislabeled or contaminated samples is a recurring challenge in independent testing, and independent laboratories may use orthogonal methods to verify identity.
Detection of SR9009 in biological samples usually relies on liquid chromatography coupled to tandem mass spectrometry. This approach separates the compound from matrix components and identifies it by mass transitions. Because SR9009 can undergo metabolism, laboratories often look for both parent drug and specific metabolites. Sample preparation may involve protein precipitation or solid-phase extraction. Method validation examines sensitivity, carryover, and interference from related substances, and reference standards are required for accurate calibration.
Storage conditions for research-grade SR9009 generally involve a freezer at approximately minus twenty degrees Celsius, sometimes lower for long-term preservation. Containers should remain tightly closed and protected from light. Desiccants may be used to limit moisture uptake. Solutions are often stored in aliquots to avoid repeated warming and cooling. Stability data for the compound under various conditions are limited, so laboratories typically follow supplier recommendations and verify performance through periodic analytical checks rather than assuming indefinite stability.
Identity and purity testing for SR9009 commonly uses liquid chromatography coupled with tandem mass spectrometry. This method separates the compound from matrix components and detects it by mass-to-charge transitions, providing sensitive and specific confirmation. Nuclear magnetic resonance spectroscopy can support structural identification, while high-performance liquid chromatography with ultraviolet detection may estimate purity. Because online products labeled as SR9009 may contain other substances or no active compound at all, independent verification is important in research settings. Certificates of analysis are useful but not a substitute for in-house testing.
Laboratory samples of SR9009 are typically supplied as a white to off-white powder. The compound dissolves readily in organic solvents such as dimethyl sulfoxide and ethanol, while its solubility in water is low. Because of this solubility profile, researchers often prepare concentrated stock solutions in an organic solvent before diluting them into aqueous assay buffers. Light exposure, moisture, and repeated freeze-thaw cycles can degrade many small molecules, so handling procedures usually aim to minimize these factors. Purity is commonly checked before use.
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 and metabolic gene expression. In laboratory experiments, SR9009 binds these receptors and alters transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. It is not a naturally occurring compound and has no approved therapeutic use. Research interest stems from its ability to modify energy metabolism in cells and animal models.
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.
== Classification == Cerebrospinal fluid leaks are classified into two distinct disorders: cranial leaks, and spinal leaks. Where there has been no preceding surgery or medical procedure that may have caused a CSF leak it is called a spontaneous CSF leak (sCSF leak).
== Epidemiology == Myocardial infarction is a common presentation of coronary artery disease. The World Health Organization estimated in 2004, that 12.2% of worldwide deaths were from ischemic heart disease; with it being the leading cause of death in high- or middle-income countries and second only to lower respiratory infections in lower-income countries. Worldwide, more than 3 million people have STEMIs and 4 million have NSTEMIs a year. STEMIs occur about twice as often in men as women. Rates of death from ischemic heart disease (IHD) have slowed or declined in most high-income countries, although cardiovascular disease still accounted for one in three of all deaths in the US in 2008. For example, rates of death from cardiovascular disease have decreased almost a third between 2001 and 2011 in the United States. In contrast, IHD is becoming a more common cause of death in the developing world. For example, in India, IHD had become the leading cause of death by 2004, accounting for 1.46 million deaths (14% of total deaths) and deaths due to IHD were expected to double during 1985–2015. Globally, disability adjusted life years (DALYs) lost to ischemic heart disease are predicted to account for 5.5% of total DALYs in 2030, making it the second-most-important cause of disability (after unipolar depressive disorder), as well as the leading cause of death by this date.
In Australia, local soccer clubs, competitions and associations were mostly established independently and later affiliated with regional and states and territory bodies. A federated model of national, states and territories bodies developed since the first state body was established in New South Wales in 1882. Today, there is FA, the professional leagues, nine state and territory member federations and over 100 district, regional and local zones and associations.
Glycoproteins and phosphoproteins are usually associated with covalent bonds since they have a carbohydrate or phosphate residue attached to the side chains of certain amino acid residues like asparagine, serine, and threonine. On the other hand, metalloproteins usually involve coordination bonds where there would be bonds between the metal ions and side chains of some amino acids like histidine, cysteine, or aspartic acid. All of these interactions create stable structures that are important for protein function. It is common for the prosthetic group to contribute to the function of the protein. An example of this is if the prosthetic group is broken away from the protein, the function of that protein is lost. This is seen in hemoglobin. When the heme group of hemoglobin is removed, the function of the protein is lost, making it a nonfunctional protein. This all highlights the prosthetic groups importance in maintaining both the structure and protein activity of conjugated proteins.
=== Helmut Schmidt === Finance Minister Helmut Schmidt (SPD) formed a coalition and he served as Chancellor from 1974 to 1982. Hans-Dietrich Genscher, a leading FDP official, became Vice-Chancellor and Foreign Minister. Schmidt, a strong supporter of the European Community (EC) and the Atlantic alliance, emphasised his commitment to "the political unification of Europe in partnership with the USA". Mounting external problems forced Schmidt to concentrate on foreign policy and limited the domestic reforms that he could carry out. The USSR upgraded its intermediate-range missiles, which Schmidt complained was an unacceptable threat to the balance of nuclear power, because it increased the likelihood of political coercion and required a western response. NATO responded in the form of its twin-track policy. The domestic reverberations were serious inside the SPD, and undermined its coalition with the FDP. One of his major successes, in collaboration with French President Valéry Giscard d'Estaing, was the launching of the European Monetary System (EMS) in April 1978.
Sources: en.wikipedia.org
Katherine J. Franz (born 1972) is an American chemist. She is the chair of the department of chemistry at Duke University. She studies metal ion coordination in biological systems and looks to use the insight to manage species such as copper and iron. Franz was awarded the American Chemical Society Award for Encouraging Women into Careers in the Chemical Sciences.
Cinnarizine is an antihistamine and calcium channel blocker of the diphenylmethylpiperazine group. It is prescribed for nausea and vomiting due to motion sickness or other sources such as chemotherapy, vertigo, or Ménière's disease. Cinnarizine is one of the leading causes of drug-induced parkinsonism. Cinnarizine was first synthesized as R1575 by Janssen Pharmaceutica in 1955. The nonproprietary name is derived from the cinnamyl substituent on the free nitrogen atom of the benzhydrylpiperazine core, combined with the generic ending "-rizine" for "antihistaminics/cerebral (or peripheral) vasodilators". It is not available in the United States or Canada. It has also been cited as one of the most used drugs for seasickness within the British Royal Navy.
Throughout the 15th and 16th centuries, Portuguese explorers sailed the coast of Africa, established trading posts [[Economic history of Portugal#Expansion of the Portuguese empire (15th and 16th centuries)|for commodities]] especially gold and slaves, explored the Indian Ocean and eastern Asia, and established trade routes in most of southern Asia, taxing most trade criss-crossing the Indian Ocean. However, by the 16th century its enterprise in Asia was already in decline. The 1494 Treaty of Tordesillas divided newly encountered non-European territories between Portugal and Spain along a meridian west of Cape Verde, while the 1529 Treaty of Zaragoza extended this partition to the Pacific Ocean. In 1498, Vasco da Gama reached India by sea, and two years later Pedro Álvares Cabral landed in Brazil and claimed it for Portugal. During the 15th century, Portugal established the transatlantic slave-trade circuits and, by the mid-19th century, had become one of the longest-active and a significant participant in the Atlantic slave trade.
=== Number average molar mass === The number average molar mass is a way of determining the molecular mass of a polymer. Polymer molecules, even ones of the same type, come in different sizes (chain lengths, for linear polymers), so the average molecular mass will depend on the method of averaging. The number average molecular mass is the ordinary arithmetic mean or average of the molecular masses of the individual macromolecules. It is determined by measuring the molecular mass of n polymer molecules, summing the masses, and dividing by n.
Additional journal-level metrics are available from other organizations. For example, CiteScore is a metric for serial titles in Scopus launched in December 2016 by Elsevier. While these metrics apply only to journals, there are also author-level metrics, such as the h-index, that apply to individual researchers. In addition, article-level metrics measure impact at an article level instead of journal level. Other more general alternative metrics, or "altmetrics", that include article views, downloads, or mentions in social media, offer a different perspective on research impact, concentrating more on immediate social impact in and outside academia.
Sources: en.wikipedia.org
Feminizing hormone therapy, also known as transfeminine hormone therapy, is a form of gender-affirming hormone therapy (GAHT) which change the primary and secondary sex characteristics of transgender people from masculine to feminine. It is one of the two common type of GAHT the other being masculinizing hormone therapy) and is used to treat transgender women and non-binary transfeminine individuals. Some others, in particular intersex people, but also some non-transgender people, take this form of therapy according to their personal needs and preferences. The purpose of the therapy is to cause the development of the secondary sex characteristics of the desired sex, such as breasts and a feminine pattern of hair, fat, and muscle distribution. It cannot undo many of the changes produced by naturally occurring puberty, which may necessitate surgery and other treatments to reverse (see below). The medications used for feminizing hormone therapy include estrogens, antiandrogens, progestogens, and gonadotropin-releasing hormone modulators (GnRH modulators). Feminizing hormone therapy has been empirically shown to reduce the distress and discomfort associated with gender dysphoria in transfeminine individuals.
== Etymology == The word sphinx comes from the Greek Σφίγξ, associated by folk etymology with the verb σφίγγω (sphíngō), meaning "to squeeze", "to tighten up". This name may be derived from the fact that lions kill their prey by strangulation, biting the throat of prey and holding them down until they die. However, the historian Susan Wise Bauer suggests that the word "sphinx" was instead a Greek corruption of the Egyptian name "shesepankh", which meant "living image", and referred rather to the statue of the sphinx, which was carved out of "living rock" (rock that was a contiguous part of the stony body of the Earth, shaped, but not cut away from its original source), than to the beast itself.
According to some reports and textbooks, the number of adipocytes can increase in childhood and adolescence, though the amount is usually constant in adults. Individuals who become obese as adults, rather than as adolescents, have no more adipocytes than they had before.
is the unit tensor. This equation can be thought of as a generalized form of Newton's law of viscosity. The bulk viscosity (also called volume viscosity) expresses a type of internal friction that resists the shearless compression or expansion of a fluid. Knowledge of
Sources: en.wikipedia.org
It is a synthetic compound studied as an agonist of REV-ERB nuclear receptors. It is not an approved medicine and has mainly been examined in laboratory and animal research.
No. It is a small molecule that binds nuclear receptors involved in circadian regulation. Its classification differs from anabolic steroids or peptide hormones.
Published human clinical trial data are lacking. Most safety and activity information comes from preclinical models, so effects in people remain uncertain.
It is a synthetic REV-ERB agonist used mainly in preclinical research. It is not an approved medicine for human use.