If you have been reading about circadian clock and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-04-01. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic small-molecule REV-ERB agonist | Not a hormone or natural product |
| Primary targets | REV-ERBα and REV-ERBβ | Nuclear receptors involved in circadian and metabolic regulation |
| Appearance | White to off-white solid | Typical for purified research samples |
| Solubility | Soluble in DMSO and ethanol; low water solubility | Laboratory solubility depends on solvent and purity |
| Common synonyms | SR9009; Stenabolic | Stenabolic is a colloquial name, not a formal chemical name |
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.
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.
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.
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.
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.
== Awards == Borden Award (American Chemical Society) 1957 Bond Award (American Oil Chemists’ Society) 1973 Agricultural and Food Chemistry Award (American Chemical Society) 1973 Senior Scientist Award (Alexander von Humboldt Foundation) 1981 Macy-Gyorgy Award for Research in Human Milk and Lactation 1997 Penn State Alumni Fellow Award 2001 Penn State Distinguished Alumnus Award 2002
=== Other clinical classifications of necrosis === There are also very specific forms of necrosis such as gangrene (term used in clinical practices for limbs which have had severe hypoxia), gummatous necrosis (due to spirochaetal infections) and hemorrhagic necrosis (due to the blockage of venous drainage of an organ or tissue). Myonecrosis is the death of individual muscle fibres due to injury, hypoxia, or infection. Common causes include spontaneous diabetic myonecrosis (a.k.a. diabetic muscle infarction) and clostridial myonecrosis (a.k.a. gas gangrene). Some spider bites may lead to necrosis. In the United States, only spider bites from the brown recluse spider (genus Loxosceles) reliably progress to necrosis. In other countries, spiders of the same genus, such as the Chilean recluse in South America, are also known to cause necrosis. Claims that yellow sac spiders and hobo spiders possess necrotic venom have not been substantiated. In blind mole rats (genus Spalax), the process of necrosis replaces the role of the systematic apoptosis normally used in many organisms. Low oxygen conditions, such as those common in blind mole rats' burrows, usually cause cells to undergo apoptosis. In adaptation to higher tendency of cell death, blind mole rats evolved a mutation in the tumor suppressor protein p53 (which is also used in humans) to prevent cells from undergoing apoptosis. Human cancer patients have similar mutations, and blind mole rats were thought to be more susceptible to cancer because their cells cannot undergo apoptosis.
== Diagnosis == The clinical diagnosis of BPD can be made through a psychiatric assessment conducted by a mental health professional, ideally a psychiatrist or psychologist. This comprehensive assessment integrates various sources of information to confirm the diagnosis, encompassing the patient's self-reported clinical history, observations made by the clinician during interviews, and corroborative details obtained from family members, friends, and medical records. Patients should be thoroughly assessed for co-morbid mental health conditions, substance use disorders, suicidal ideation, and any self-harming behaviors. An effective approach involves presenting the criteria of the disorder to the individual and inquiring if they perceive these criteria as reflective of their experiences. Involving individuals in the diagnostic process may enhance their acceptance of the diagnosis. Despite the stigma associated with BPD and previous notions of its untreatability, disclosing the diagnosis to individuals is generally beneficial. It provides them with validation and directs them to appropriate treatment options. The psychological evaluation for BPD typically explores the onset and intensity of symptoms and their impact on the individual's quality of life. Critical areas of focus include suicidal thoughts, self-harm behaviors, and any thoughts of harming others. The diagnosis relies on both the individual's self-reported symptoms and the clinician's observations.
==== Role of inhibitory neuron classes ==== The Sur lab pioneered two-photon measurements of neuronal activity in the intact mouse brain with cell-specific manipulations of activity to discover specific and unique functions of inhibitory neuron classes in cortical responses. Probing neuromodulator-dependent mechanisms of internal states, they demonstrated that cholinergic inputs to inhibitory neuron classes shape the temporal dynamics of cortical activity, including neuronal desynchronization during arousal and attention. Role of norepinephrine in cortical circuits and learning The Sur lab showed that control of norepinephrine release by locus coeruleus neurons via local GABAergic neurons strongly influences arousal, and phasic norepinephrine activity signals uncertainty and reward prediction to modulate task execution and reinforcement learning during goal-directed behavior. Together, these discoveries have shaped the understanding that specific excitatory and inhibitory cortical circuits mediate unique functions, and neuromodulator systems act via cell-specific circuits to modulate cortical functions, brain states and learning.
=== UV-induced DNA damage === UV-irradiation of human skin cells generates damages in DNA through direct photochemical reactions at adjacent thymine or cytosine residues on the same strand of DNA. Cyclobutane pyrimidine dimers formed by two adjacent thymine bases, or by two adjacent cytosine bases, in DNA are the most frequent types of DNA damage induced by UV. Humans, as well as other organisms, are capable of repairing such UV-induced damages by the process of nucleotide excision repair. In humans this repair process protects against skin cancer.
Sources: en.wikipedia.org
Gaesser, Glenn A; Brooks, George A (1984). "Metabolic bases of excess post-exercise oxygen consumption: a review". Medicine & Science in Sports & Exercise. 16 (1): 29–43. doi:10.1249/00005768-198401000-00008. PMID 6369064.
In enzymology, an aromatic 2-oxoacid reductase (EC 1.1.1.110, previously indolelactate dehydrogenase) is an enzyme that catalyzes the reversible oxidation and reduction of aryllactate compounds to arylpyruvate compounds using the redox cofactor nicotinamide adenine dinucleotide or the similar nicotinamide adenine dinucleotide phosphate. For example, the enzyme may oxidize (R)-3-(4-hydroxyphenyl)lactate to 3-(4-hydroxyphenyl)pyruvic acid.
=== Dual inspired bioadhesives === By combining the catechol chemistry in marine mussels which is responsible for their ability to form strong wet adhesions, and the dissipative matrix found in the mucus of land slugs a dual bio inspired hydrogel adhesive was created. A double-bioinspired hydrogel adhesive (DBHA) thus consists of an intertwined catechol modified peptide dendrimer (G3KPC) with an anionic carboxymethyl cellulose and cationic chitosan (CC), network through covalent and noncovalent cross-linkages. This hydrogel has self healing abbilities due to the nature of the schiff base reaction, Micheal addition, and multiple noncovalent cross linkages in the gel, which allows them to re-cross link together with ease.
Among those from the world of politics to be recognised in the 2024 Birthday Honours is former prime minister Gordon Brown, who is made a Companion of Honour, and former MP Wayne David, who receives a knighthood. 16 June – Grant StClair-Armstrong, the Reform UK candidate for North West Essex, resigns from the party after historic blog posts emerge in which he urged people to vote for the British National Party. ITV Wales holds an election debate between senior figures from the three main political parties in Wales; David TC Davies (Conservative), Jo Stevens (Labour) and Liz Saville Roberts (Plaid Cymru). 17 June – Nigel Farage launches Reform UK's election manifesto, which he describes as a contract, and which chiefly proposes a freeze on non-essential immigration. Lord Cashman is suspended from the Parliamentary Labour Party for describing Rosie Duffield as "frit or lazy" in a social media post for withdrawing from hustings meetings over concerns for her safety. BBC Sounds launches an Election 2024 livestream, bringing together all the election news and programming, such as Newscast, Today, Question Time and Sunday with Laura Kuenssberg. The livestream is scheduled to run until 8 July. 18 June – LBC's Nick Ferrari presents the first of two editions of Britain's Next PM, a phone-in giving listeners the opportunity to speak to Keir Starmer and Rishi Sunak, with Starmer appearing on the first edition and Sunak the following day. The deadline for people wishing to register to vote in time for the 2024 general election expires at 23:59.
Adenylyl-sulfate reductase (glutathione) (EC 1.8.4.9) is an enzyme that catalyzes the chemical reaction AMP + sulfite + glutathione disulfide ⇌ {\displaystyle \rightleftharpoons } adenylyl sulfate + 2 glutathione The 3 substrates of this enzyme are adenosine monophosphate, sulfite, and glutathione disulfide, whereas its two products are adenylyl sulfate and glutathione. This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with a disulfide as acceptor. The systematic name of this enzyme class is AMP,sulfite:glutathione-disulfide oxidoreductase (adenosine-5'-phosphosulfate-forming). Other names in common use include 5'-adenylylsulfate reductase (also used for, internal_xref(ec_num(1,8,99,2))), AMP,sulfite:oxidized-glutathione oxidoreductase, (adenosine-5'-phosphosulfate-forming), and plant-type 5'-adenylylsulfate reductase. In plants, APS is reduced by the plastidic enzyme APS reductase (APR; EC 1.8.4.9) in the presence of physiological concentrations of reduced glutathione (GSH), which acts as an electron donor.
Sources: en.wikipedia.org
=== Modern reception === Bloodlines is considered a cult classic. Retrospective critiques continue to praise the game's narrative and degree of choice. In 2009, an article in Rock, Paper, Shotgun declared: "The sense of sorrow comes from the realization that there's nothing like [Bloodlines] on the horizon ... why should there be so few games like this? Oh right, because it's so very hard to do ... the lack of games comparable to Bloodlines is one of the great tragedies of our time." Eurogamer called the game inspirational, with an unmatched level of narrative detail. In 2010, The Escapist called Bloodlines a flawed masterpiece which could have been a genuine masterpiece with more time, money, and staff; although great games may inspire awe, it instead created a devoted fan base which continued to develop the game. In 2006, PC Zone listed Bloodlines the seventh-best PC game which people were unlikely to have played, calling it the "best buggy game ever released". In 2007, the game was 80th on Computer & Video Games' list of its top 100 games, and 86th on PC Gamer's 2014 list of the same; it also appeared in PC Gamer's 2015 edition (moving to 63rd), 2017 edition (moving to 42nd), and 2021 edition (moving to 93rd). In 2008, bit-tech listed Jeanette as the second-best non-player video game character. In 2011, Rock, Paper, Shotgun called Bloodlines one of the most important PC games of all time ("it signposts a direction to a future of games that we were denied"), listing it as one of the 122 Best PC Games Ever.
Empagliflozin, sold under the brand name Jardiance ( JAR-dee-əns), among others, is an antidiabetic medication used to improve glucose control in people with type 2 diabetes and/or for patients with established heart failure with reduced ejection fraction (HFrEF). Studies have shown great benefits for heart failure (HF) outcomes and decreased hospitalisations. It is taken by mouth. Common side effects of empagliflozin include genital yeast infections and hypotension, particularly in patients with volume depletion. Other symptoms such as nausea and vomiting may occur and seem more pronounced in combination with metformin. Rare but serious adverse events, such as euglycemic diabetic ketoacidosis (DKA) which may present with hyperventilation, lethargy, or mental status changes have been reported but are infrequent in trials. Other serious but rare serious adverse events include Fournier's gangrene, a severe skin infection of the groin, and diabetic ketoacidosis that may occur even with normal blood glucose levels. Use during pregnancy or breastfeeding is not recommended. Empagliflozin is a SGLT2 inhibitor: a reversible inhibitor of the sodium glucose co-transporter-2 (SGLT-2). It reduces the kidney's glucose reabsorption and excretes the excess glucose through the urine, thus its place in the treatment of type two diabetes. It is dependent on blood glucose concentrations and the glomerular filtration rate of the kidney.
Fermentation is less efficient at using the energy from glucose: only 2 ATP are produced per glucose, compared to the 38 ATP per glucose nominally produced by aerobic respiration. Glycolytic ATP, however, is produced more quickly. For prokaryotes to continue a rapid growth rate when they are shifted from an aerobic environment to an anaerobic environment, they must increase the rate of the glycolytic reactions. For multicellular organisms, during short bursts of strenuous activity, muscle cells use fermentation to supplement the ATP production from the slower aerobic respiration, so fermentation may be used by a cell even before the oxygen levels are depleted, as is the case in sports that do not require athletes to pace themselves, such as sprinting.
== The proteome in bacterial systems == Proteomic analyses have been performed in different kinds of bacteria to assess their metabolic reactions to different conditions. For example, in bacteria such as Clostridium and Bacillus, proteomic analyses were used in order to investigate how different proteins help each of these bacteria spores germinate after a prolonged period of dormancy. In order to better understand how to properly eliminate spores, proteomic analysis must be performed.
Sources: en.wikipedia.org
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.
It binds REV-ERBα and REV-ERBβ and changes transcription of metabolic genes. This can affect circadian rhythm, lipid use, and mitochondrial function. The full downstream effects are still under study.
No. Some rodent studies show increased endurance, but controlled human trials are lacking. Claims about human performance are not established by published evidence.
Research-grade SR9009 is typically stored frozen at about minus twenty degrees Celsius, protected from light and moisture. Stock solutions are often kept in aliquots to avoid repeated freeze-thaw cycles. Specific storage conditions should follow the supplier's documentation.