circadian rhythm is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-03-26. Where a claim depends on a specific study, the study is described rather than over-claimed.
Analytical identification of SR9009 typically relies on liquid chromatography coupled with tandem mass spectrometry. In biological samples, researchers first separate the compound from matrix components using protein precipitation, liquid-liquid extraction, or solid-phase extraction. High-performance liquid chromatography with ultraviolet detection and nuclear magnetic resonance spectroscopy can support structural confirmation of reference materials. Because SR9009 is a small, relatively lipophilic molecule, reverse-phase columns and acidic mobile phases are common. Laboratories often include isotope-labeled internal standards to improve quantification and to correct for ion suppression.
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.
Identity and purity of SR9009 samples are usually checked with chromatographic and spectrometric methods. High-performance liquid chromatography can separate the compound from related impurities, while mass spectrometry provides molecular mass confirmation. Nuclear magnetic resonance spectroscopy may be used for structural verification in research settings. No single method proves biological activity, and certificates of analysis should be reviewed alongside raw data. Independent testing is often needed because online products vary widely.
SR9009 stability depends on temperature, moisture, light, and solvent. Solid material is generally kept cool and dry, while solutions may require protection from repeated warming and cooling. Degradation can appear as color changes, precipitate, or new chromatographic peaks. Researchers should follow supplier instructions and their own stability data. Long-term storage conditions for human use have not been established because the compound lacks approved clinical formulation.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | SR9009; Stenabolic | Nickname is not a chemical name. |
| Typical analytical method | LC-MS/MS | Often with isotope-labeled internal standard. |
| Storage temperature | -20 °C | Desiccated and protected from light. |
| Solution stability | DMSO stock; avoid freeze-thaw | Store at -20 to -80 °C. |
| Regulatory status | Not approved; varies by country | May be restricted as research chemical. |
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.
Mechanistically, SR9009 binds the ligand-binding domain of REV-ERBα/β and enhances recruitment of corepressor complexes. This represses target genes rather than activating them. Because REV-ERB proteins normally compete with ROR proteins at shared response elements, the net effect depends on tissue and timing. Researchers use SR9009 to probe how nuclear receptor signaling links the clock to metabolism, inflammation, and muscle biology. Findings are largely preclinical, and the precise contribution of each receptor subtype remains under study.
SR9009 is frequently discussed in fitness and research-chemical contexts, yet it has no approved medical indication. Regulatory agencies have not authorized it for human use, and it is not a standard prescription drug. Some sports organizations list it as a prohibited substance because of its potential performance-enhancing properties. Published human data are sparse, so claims about its effects in people often rely on animal models or anecdotal reports. Quality and identity of online materials can vary widely.
1825 The first publication of the Gompertz–Makeham law of mortality that in the simplest form is: p = a + bx. According to the law, the probability of death p is defined as the sum of age-independent component a and the component depending on age bx which with age increases exponentially. If we place organisms in an absolutely protected environment and in this way make the first component negligible, the probability of death will be completely defined by the second component which actually describes the probability to die from aging. 1860s Alfred Russel Wallace writes down what is probably the first evolutionary theory of aging. In notes written sometime between 1865 and 1870, he proposed a wear and tear theory of aging, suggesting that older animals which continue to consume resources, competing with their offspring in an environment with limited food, were disfavored by natural selection. Therefore, he suggested that aging was an evolved trait which allowed an organism's descendants to thrive. 1882 August Weismann puts forward the wear and tear theory of aging independently of Wallace. 1889 Rejuvenation experiment conducted on himself by the French doctor Charles-Édouard Brown-Séquard. He made himself a few subcutaneous injections from the testicles of young dogs and guinea pigs and claimed that the injections were accompanied by significant and long pain, but then he observed an improvement of the physical condition of the organism and increase of mental activity.
transposition The process by which a nucleic acid sequence known as a transposable element changes its position within a genome, either by excising and re-inserting itself at a different locus (cut-and-paste) or by duplicating itself and inserting into another locus without moving the original element from its original locus (copy-paste). These reactions are catalyzed by an enzyme known as a transposase which is encoded by a gene within the transposable element itself; thus the element's products are self-acting and can autonomously direct their own replication. Transposed sequences may re-insert at random loci or at sequence-specific targets, either on the same DNA molecule or on different molecules.
=== 2023: French Open semifinals, Hamburg title === Zverev returned to the tour for the first time since his ankle injury by participating at the inaugural United Cup where he lost in straight sets to Jiří Lehečka and Taylor Fritz. Seeded 12th at the Australian Open, he won his first match since June 2022 by beating lucky loser, Juan Pablo Varillas, in the first round in five sets. He was defeated in the second round by American and lucky loser, Michael Mmoh, in four sets. After the Australian Open, Zverev represented Germany in the Davis Cup tie against Switzerland. He won his first match over Stan Wawrinka. He lost his second match to Marc-Andrea Hüsler. Switzerland ended up winning the tie over Germany 3–2. Seeded eighth at the Rotterdam Open, he was eliminated from the tournament in the second round by Dutch wildcard, Tallon Griekspoor, in three sets. Seeded fourth at the Qatar ExxonMobil Open, he fell in the second round to wildcard, former world No. 1, two-time champion, and eventual finalist, Andy Murray. In March, he played at the Dubai Championships. Seeded seventh, he reached the semifinals where he lost to second seed, defending champion, and eventual finalist, Andrey Rublev. Zverev began his early U.S. hard court campaign at the Indian Wells Masters. Seeded 12th, he reached the fourth round but lost to fifth seed, world No. 6, and eventual finalist, Daniil Medvedev, in three close sets. Seeded 13th at the Miami Open, he was beaten in the second round by wildcard Taro Daniel. Zverev began his clay-court season at the Monte-Carlo Masters.
=== Pharmacodynamics === Nalorphine acts at two opioid receptors — the μ-opioid receptor (MOR) where it has antagonistic effects, and at the κ-opioid receptor (KOR) (Ki = 1.6 nM; EC50 = 483 nM; Emax = 95%) where it exerts high-efficacy partial agonist/near-full agonist characteristics.
Sources: en.wikipedia.org
=== Children === Its use in children is generally advised against, although it may be done under the supervision of a specialist. On 21 September 2015, the FDA started investigating the safety of tramadol in use in persons under the age of 17. The investigation was initiated because some of these people have experienced slowed or difficult breathing. The FDA lists age under 12 years old as a contraindication.
In 1858, William Parker Foulke discovered the first known American dinosaur in marl pits in the small town of Haddonfield, New Jersey. (Although fossils had been found before, their nature had not been correctly discerned.) The creature was named Hadrosaurus foulkii. It was an extremely important find: Hadrosaurus was one of the first nearly complete dinosaur skeletons found (the first was in 1834, in Maidstone, England), and it was clearly a bipedal creature. This was a revolutionary discovery as, until that point, most scientists had assumed dinosaurs walked on four feet, like other lizards. Foulke's discoveries sparked a wave of interests in dinosaurs in the United States, known as Dinosaur Mania. Dinosaur mania was exemplified by the fierce rivalry between Edward Drinker Cope and Othniel Charles Marsh, both of whom raced to be the first to find new dinosaurs in what came to be known as the Bone Wars. This fight between the two scientists lasted for over 30 years, ending in 1897 when Cope died after spending his entire fortune on the dinosaur hunt. Many valuable dinosaur specimens were damaged or destroyed due to the pair's rough methods: for example, their diggers often used dynamite to unearth bones. Modern paleontologists would find such methods crude and unacceptable, since blasting easily destroys fossil and stratigraphic evidence. Despite their unrefined methods, the contributions of Cope and Marsh to paleontology were vast: Marsh unearthed 86 new species of dinosaur and Cope discovered 56, a total of 142 new species.
==== Cylindrical ion trap ==== The cylindrical ion trap mass spectrometer (CIT) is a derivative of the quadrupole ion trap where the electrodes are formed from flat rings rather than hyperbolic shaped electrodes. The architecture lends itself well to miniaturization because as the size of a trap is reduced, the shape of the electric field near the center of the trap, the region where the ions are trapped, forms a shape similar to that of a hyperbolic trap.
The first cuprate superconductor was found in 1986 in the non-stoichiometric cuprate lanthanum barium copper oxide by IBM researchers Georg Bednorz and Karl Alex Müller. The critical temperature for this material was 35K, well above the previous record of 23 K. The discovery led to a sharp increase in research on the cuprates, resulting in thousands of publications between 1986 and 2001. Bednorz and Müller were awarded the Nobel Prize in Physics in 1987, only a year after their discovery. From 1986, many cuprate superconductors were identified, and can be put into three groups on a phase diagram critical temperature vs. oxygen hole content and copper hole content:
Alan Dershowitz, Claus's attorney, wrote a book about the case, Reversal of Fortune: Inside the von Bülow Case (New York, Random House 1986 and London, Penguin Books 1991). The 1990 film Reversal of Fortune was based on Dershowitz's books about the case, with Glenn Close playing Sunny and Jeremy Irons playing Claus von Bülow, a performance for which he was awarded an Academy Award for Best Actor. Bill Kurtis narrated an episode of the series American Justice titled "Von Bulow: A Wealth of Evidence". The American television series Biography produced and aired a documentary episode titled "Claus von Bülow: A Reasonable Doubt", with interviews of Claus Von Bülow and Alan Dershowitz. The case is referenced in the Seinfeld episode "The Suicide". Jerry Seinfeld is in a hospital room watching over a comatose neighbor. To the neighbor's ex-girlfriend he remarked, "It's not like a Sunny Von Bülow coma. Doctor said he should snap out of it anytime." Sunny is referenced in the American television show Will & Grace, in which socialite Karen Walker asks more than once about Sunny being “out of bed.”
Sources: en.wikipedia.org
=== Growth hormone-like activity === hPL has weak actions, similar to those of growth hormone, causing the formation of protein tissues in the same way that growth hormone, but 100 times more hPL than growth hormone is required to promote growth. However, hPL has a blood level of more than 50 times that of hGH, hence its effects must not be ignored. An enhancer for the human placental lactogen gene is found 2 kb downstream of the gene and participates in the cell-specific control gene expression.
=== Protein stabilization for optimized isolation === Thermofluor pre-screens can be performed that sample a wide range of pH, ionic strength, and additives such as added metal ions and cofactors. The generation of a protein response surface is useful for establishing optimal assay conditions and can frequently lead to improved purification scheme as required to support HTS campaigns and biophysical studies.
Lavín, José L; Kiil, Kristoffer; Resano, Ohiana; Ussery, David W; Oguiza, José A (2007). "Comparative genomic analysis of two-component regulatory proteins in Pseudomonas syringae". BMC Genomics. 8 397. doi:10.1186/1471-2164-8-397. PMC 2222644. PMID 17971244. Type strain of Pseudomonas syringae at BacDive – the Bacterial Diversity Metadatabase
== History == Pregabalin was synthesized in 1990 as an anticonvulsant that was developed as a successor to the related gabapentin. It was first synthesized by medicinal chemist Richard Bruce Silverman at Northwestern University in Evanston, Illinois. During 1988 to 1990, Ryszard Andruszkiewicz, a visiting research fellow, synthesized a series of molecules requested by Silverman. Upon testing in mouse seizure models by collaborators at Parke-Davis Pharmaceuticals, one looked particularly promising. In vitro, it activated L-glutamic acid decarboxylase, an enzyme, but this later proved to be unimportant to prevention of seizures. Silverman had originally hoped that the enzyme would increase the production of the inhibitory neurotransmitter GABA and block convulsions. After extensive development studies and clinical trials by Parke-Davis the drug was approved in the European Union in 2004. The US received FDA approval for use in treating epilepsy, diabetic neuropathic pain, and postherpetic neuralgia in December 2004. Pregabalin then appeared on the US market under the brand name Lyrica in the fall of 2005. In 2017, the FDA approved pregabalin extended-release Lyrica CR for the management of neuropathic pain associated with diabetic peripheral neuropathy, and postherpetic neuralgia. However, unlike the immediate release formulation, Lyrica CR was not approved for the management of fibromyalgia or as add-on therapy for adults with partial onset seizures.
Sources: en.wikipedia.org
The most common approach is liquid chromatography-tandem mass spectrometry, often after extraction from blood, urine, or tissue. Ultraviolet detection and nuclear magnetic resonance spectroscopy are used mainly for reference material characterization. Isotope-labeled internal standards improve accuracy.
Solid material is usually kept at -20 °C, desiccated, and protected from light. Dimethyl sulfoxide stocks should be stored cold and subjected to minimal freeze-thaw cycles. Aqueous solutions are generally less stable and should be prepared fresh when possible.
Legality depends on the country and the intended use. It is not an approved medicine, and some places restrict or ban sales for human consumption. Buyers should verify local rules and product documentation before procurement.
Laboratories commonly use liquid chromatography coupled with mass spectrometry to detect SR9009. The method can identify the compound and estimate concentration in a sample. Detection limits depend on the matrix and instrument.