circadian clock comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-06-19. Where a claim depends on a specific study, the study is described rather than over-claimed.
Regulatory treatment of SR9009 reflects its investigational status. The compound has no approved human therapeutic indication, and sports authorities prohibit its use. It appears on anti-doping lists as a non-approved substance or metabolic modulator, depending on the list version. Products sold online as research chemicals are not quality-controlled medicines, so their identity and purity can differ from the label. Such products may also contain unlisted compounds, which complicates both testing and safety assessment.
Scientific discussion of SR9009 often separates animal evidence from human anecdote. Rodent studies provide controlled data on endurance, metabolism, and gene expression, but they use specific strains, doses, and treatment durations. Human reports are mostly uncontrolled and cannot establish cause and effect. Open questions include oral bioavailability, tissue distribution, metabolic stability, and long-term effects. Review articles generally call for more rigorous pharmacokinetic and safety research before any clinical use could be considered.
Analytical methods for SR9009 typically rely on liquid chromatography coupled with tandem mass spectrometry. The technique can separate the parent compound from related substances and detect low concentrations in biological matrices. Urine and blood are common samples in anti-doping testing, while in vitro studies may use cell culture media. Rapid metabolism and low expected concentrations make method validation important for reliable identification. Exact metabolite patterns can vary by species and are not fully mapped.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ, also called NR1D1 and NR1D2. These receptors help regulate circadian rhythms and metabolic gene programs. The compound was developed for laboratory research, not as an approved therapeutic. Its identity is distinct from steroid hormones and selective androgen receptor modulators. Scientific interest centers on how REV-ERB activation changes gene expression in cells and animal models.
At the molecular level, SR9009 binds the ligand-binding domain of REV-ERB and strengthens recruitment of corepressor proteins such as NCoR and HDAC3. This increases repression of target genes, including Bmal1 and other clock-controlled and metabolic genes. In rodent studies, such changes have been linked to altered lipid handling, glucose metabolism, and energy expenditure. The precise chain of events between receptor binding and whole-body effects remains an active area of research. Findings in animals do not automatically translate to humans.
Laboratory studies often administer SR9009 by injection because oral absorption appears poor in rodents. Reported pharmacokinetic properties include rapid metabolism and low systemic exposure after oral dosing. Human pharmacokinetic data are sparse, so absorption, distribution, metabolism, and excretion in people are not well defined. Some research explores related REV-ERB compounds with improved drug-like properties. Regulatory approval for any REV-ERB agonist as a human medicine has not been granted to date.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Not approved for human use | Investigational status in most countries |
| Sports status | Prohibited by WADA | Classified as non-approved or metabolic modulator |
| Common analytical method | LC-MS/MS | Used for trace detection in biological samples |
| Typical test matrices | Urine and blood | Sample choice depends on testing program |
| Human trial data | None published | Effects and safety are not established |
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.
Preclinical reports describe effects on exercise endurance, mitochondrial content, and lipid profiles in rodents, but these findings come from specific experimental conditions. Many studies use high doses or delivery methods that may not translate directly to human use. SR9009 has been reported to have low oral bioavailability and a short half-life, which complicates interpretation of oral dosing studies. It is not established as safe or effective for any indication. Literature discussions often separate its pharmacological mechanism from unverified claims made in fitness and supplement markets.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is not an approved medicine and has no established human therapeutic use. The compound appears in scientific literature as a tool for probing circadian and metabolic regulation. Online sellers often label it as a research chemical, sometimes using the nickname Stenabolic. Its chemical identity is distinct from selective androgen receptor modulators, stimulants, and peroxisome proliferator-activated receptor delta agonists. Researchers use it mainly in cell and animal experiments.
At the molecular level, SR9009 binds REV-ERBα and REV-ERBβ and alters their repressive activity on target genes. These nuclear receptors help regulate the circadian clock, lipid synthesis, glucose metabolism, and inflammatory pathways. By changing transcription, the compound can shift the timing or magnitude of downstream metabolic processes in model systems. It does not act through androgen receptors or adenosine receptors, which distinguishes it from several substances sold for athletic performance. Whether the same transcriptional changes occur in humans at tolerable exposures remains an open question because controlled human studies are lacking.
SR9009 is generally described as poorly soluble in water and more soluble in organic solvents such as dimethyl sulfoxide and ethanol. Stock solutions are commonly prepared in an organic solvent before dilution into an aqueous buffer or vehicle. Precipitation can occur if the organic fraction is reduced too quickly or if the final concentration exceeds the compound's solubility limit. Sonication or gentle warming may aid dissolution in some protocols, but excessive heat can promote degradation. Container material and pH can also influence observed solubility.
For long-term storage, SR9009 is typically kept as a solid at low temperature, protected from moisture and light. Desiccated conditions limit hydrolysis, while opaque containers reduce photochemical breakdown. Solutions are less stable than solids and are often stored frozen in aliquots to avoid repeated freeze-thaw cycles. Stability data are not standardized across all suppliers, so users should rely on certificate-of-analysis information when available. Degradation may appear as color change, precipitate, or decreased chromatographic purity.
==== Total synthesis ==== Some steroidal hormones are economically obtained only by total synthesis from petrochemicals (e.g. 13-alkyl steroids). For example, the pharmaceutical Norgestrel begins from methoxy-1-tetralone, a petrochemical derived from phenol.
=== Research for therapeutic use === The classification of L-serine as a non-essential amino acid has come to be considered as conditional, since vertebrates such as humans cannot always synthesize optimal quantities over entire lifespans. Safety of L-serine has been demonstrated in an FDA-approved human phase I clinical trial with Amyotrophic Lateral Sclerosis, ALS, patients (ClinicalTrials.gov identifier: NCT01835782), but treatment of ALS symptoms has yet to be shown. A 2011 meta-analysis found adjunctive sarcosine to have a medium effect size for negative and total symptoms of schizophrenia. There also is evidence that L‐serine could acquire a therapeutic role in diabetes. D-Serine is being studied in rodents as a potential treatment for schizophrenia. D-Serine also has been described as a potential biomarker for early Alzheimer's disease (AD) diagnosis, due to a relatively high concentration of it in the cerebrospinal fluid of probable AD patients. D-serine, which is made in the brain, has been shown to work as an antagonist/inverse co-agonist of t-NMDA receptors mitigating neuron loss in an animal model of temporal lobe epilepsy. D-Serine has been theorized as a potential treatment for sensorineural hearing disorders such as hearing loss and tinnitus.
Lysergamides are ergoline derivatives related to the ergot alkaloids. They are notable in containing both tryptamine and phenethylamine within their chemical structures. As such, ergolines and lysergamides may be considered structurally related to the monoamine neurotransmitters. Many ergolines and lysergamides act as highly promiscuous ligands of monoamine receptors, including of serotonin, dopamine, and adrenergic receptors. Some lysergamides are efficacious serotonin 5-HT2A receptor agonists and thereby produce psychedelic effects. Examples of psychedelic lysergamides include lysergic acid diethylamide (LSD), ergine (lysergic acid amide; LSA), isoergine (isolysergic acid amide; iso-LSA), ETH-LAD, AL-LAD, 1P-LSD, 1S-LSD, ALD-52 (1A-LSD), LSZ, ergonovine (ergometrine; lysergic acid propanolamide), methylergometrine (methylergonovine), and methysergide (methylmethylergonovine), among others. Ergine, isoergine, and ergonovine occur naturally in morning glories and certain fungi like ergot and Periglandula species, while others like LSD are synthetic. LSD and ETH-LAD are among the most potent psychedelics, and psychoactive drugs, known to man.
Sources: en.wikipedia.org
==== Fluorocarbons ==== Fluorocarbons and especially perfluorocarbons are excellent substrate materials for the creation of superhydrophobic surfaces due to their extremely low surface energy. These materials are synthesized by replacing hydrogen atoms with fluorine atoms of a hydrocarbon.
== Experiments on seismic metamaterials == In 2012, researchers held an experimental field-test near Grenoble, France, with the aim to highlight analogy with phononic crystals. At the geophysics scale, in a forest in the Landes region of France in 2016, an ambitious seismic experiment called the METAFORET experiment demonstrated that trees could significantly modify the surface wavefield due to their coupled resonances when arranged at a subwavelength scale. Actual use of trees for earthquake protection is not feasible, since tree heights of 260–300 feet (79–91 m) are required to dampen waves produced by earthquakes, and the species of trees, such as redwoods, that are capable of reaching this height range when mature are slow-growing. A follow-up field experiment called the META-WT experiment was performed in the Nauen wind farm. This for the first time demonstrated that, at the city scale, collective resonance of wind-turbine structures can modify seismic waves propagating through it. These new observations have implications for seismic hazard in a city where dense urban structures like tall buildings can strongly modify the wavefield.
The expanding liver bud is colonized by hematopoietic cells. The bipotential hepatoblasts begin differentiating into biliary epithelial cells and hepatocytes. The biliary epithelial cells differentiate from hepatoblasts around portal veins, first producing a monolayer, and then a bilayer of cuboidal cells. In ductal plate, focal dilations emerge at points in the bilayer, become surrounded by portal mesenchyme, and undergo tubulogenesis into intrahepatic bile ducts. Hepatoblasts not adjacent to portal veins instead differentiate into hepatocytes and arrange into cords lined by sinusoidal epithelial cells and bile canaliculi. Once hepatoblasts are specified into hepatocytes and undergo further expansion, they begin acquiring the functions of a mature hepatocyte, and eventually mature hepatocytes appear as highly polarized epithelial cells with abundant glycogen accumulation. In the adult liver, hepatocytes are not equivalent, with position along the portocentrovenular axis within a liver lobule dictating expression of metabolic genes involved in drug metabolism, carbohydrate metabolism, ammonia detoxification, and bile production and secretion. WNT/β-catenin has been identified as playing a key role in this phenomenon.
=== Immigration === Pritzker supports Syrian refugees, and criticized the first Trump administration and Rauner for "turning a blind eye on them". He also supports enhancing funding for immigrant and refugee services, increasing health care options for undocumented immigrants, improving the U-Visa certification process for victims of violent crimes, and providing access to financial aid for undocumented students such as DACA recipients. He has said he would sign the "Illinois Trust Act", a pro-immigration bill. In January 2025, when asked about the mass deportation of illegal immigrants in the second presidency of Donald Trump, Pritzker spoke in favor of deporting convicted criminals who are undocumented, but criticized the targeting of "law-abiding residents" who are integrated into communities.
Sources: en.wikipedia.org
No. It is an investigational compound without approved therapeutic indications. It is sold for research purposes only in many jurisdictions.
Sports authorities prohibit it because it is not approved for human use and has potential performance-enhancing effects. It appears on anti-doping lists under non-approved or metabolic modulator categories.
Detection usually uses liquid chromatography-tandem mass spectrometry. The method targets the parent compound or its metabolites in urine or blood.
SR9009 is a synthetic research compound that activates the REV-ERBα and REV-ERBβ nuclear receptors. It is not an approved drug and has no established human therapeutic use. Most published biological data come from cell and rodent studies.