circadian rhythm 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 2026-03-15. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic small molecule | Studied as a REV-ERB agonist |
| Molecular formula | C20H24ClN3O4S | Reported for the neutral compound |
| Appearance | Off-white to pale yellow solid | Typical research-grade material |
| Solubility | Sparingly soluble in water | Soluble in solvents such as DMSO |
| Common synonyms | SR9009; Stenabolic | Stenabolic is an informal alias |
REV-ERB proteins typically suppress gene expression by recruiting corepressor complexes to DNA response elements. SR9009 binds these receptors and strengthens that repressive action in cell-based assays. Studies in rodents have reported changes in lipid handling, mitochondrial function, and exercise capacity after treatment. Such findings are often cited as evidence for metabolic effects, but species differences and limited pharmacokinetic data make direct translation to humans uncertain. Researchers continue to examine which effects are robust and which depend on specific experimental conditions.
SR9009 is frequently discussed alongside other REV-ERB ligands, including synthetic agonists and natural heme-related molecules. Its selectivity for REV-ERB over related nuclear receptors has been measured in binding and reporter assays, though off-target activity at higher concentrations is possible. The compound is prohibited in sport by the World Anti-Doping Agency, and it is not approved for any medical use in major jurisdictions. Products sold online may be labeled as research chemicals, and their identity and purity are not guaranteed by regulatory review.
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.
Laboratory identification of SR9009 typically relies on chromatographic separation coupled to mass spectrometry, often with ultraviolet detection as a secondary check. Nuclear magnetic resonance spectroscopy can confirm molecular structure when a reference standard is available. Because many suppliers sell the compound as a research chemical, independent identity testing is important for experimental reproducibility. A single retention time is not sufficient proof of identity, especially when related compounds may be present. Purity assessments usually report a percentage based on area normalization.
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.
Storage recommendations for SR9009 reference material typically specify a freezer at -20 °C or lower, with protection from moisture and light. Repeated freeze-thaw cycles can degrade small molecules and introduce variability. Stock solutions in dimethyl sulfoxide are often aliquoted to avoid repeated handling. Stability studies may examine degradation under heat, humidity, and light exposure. The compound's thiophene and nitro groups can participate in reactions that alter analytical signals over time, so such changes affect quantitative results.
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.
Analytical chemists detect SR9009 with liquid chromatography-tandem mass spectrometry, commonly abbreviated LC-MS/MS. Sample preparation may involve protein precipitation, liquid-liquid extraction, or solid-phase extraction before analysis. Laboratories can target the parent compound or its metabolites, depending on the matrix and the purpose of testing. Anti-doping methods require sensitive and specific assays because concentrations in biological samples can be low. Reference standards and validated methods are essential for reliable identification and quantification.
Regulatory agencies have not approved SR9009 for human therapeutic use. It is typically sold as a research chemical with labels stating that it is not for human consumption. The World Anti-Doping Agency prohibits the substance in sport, generally under the category of non-approved substances. Customs and national laws may restrict importation, sale, or possession. Product quality and legal status can vary by country and vendor, and therapeutic claims are not permitted in regulated advertising because the compound lacks approval.
=== Head of intelligence === Noriega proved to be a very capable head of intelligence. During his tenure, he exiled 1,300 Panamanians whom he viewed as threats to the government. He also kept files on several officials within the military, the government, and the judiciary, allowing him to blackmail them later. Noriega also held the positions of head of the political police and head of immigration. His tenure was marked by intimidation and harassment of opposition parties and their leaders. He was described as doing much of Torrijos's "dirty work". For instance, Noriega ordered the death of Jesús Héctor Gallego Herrera, a priest whose work at an agricultural cooperative was seen as a threat by the government. Gallego's body is reported to have been thrown from a helicopter into the sea. He also made an effort during this period to portray Panama as a hub of enforcement against drug smuggling, possibly as a result of pressure from Torrijos. By the early 1970s, American law enforcement officials had reports of Noriega's possible involvement with narcotics trafficking. No formal criminal investigations were begun, and no indictment was brought: according to Dinges, this was due to the potential diplomatic consequences. This evidence included the testimony of an arrested boat courier, and of a drug smuggler arrested in New York. Though Torrijos frequently promised the U.S. cooperation in dealing with drug smuggling, Noriega would have headed any effort at enforcement, and the U.S. began to see Noriega as an obstacle to combatting drug smuggling. Dinges writes that the U.S.
== Society and culture == Golodirsen is one of the very few FDA-approved exon-skipping therapy for Duchenne muscular dystrophy, although the clinical benefits of the medication are yet to established. While the development of golodirsen needed huge financing, it is only applicable to a small subset of people with Duchenne muscular dystrophy. Sarepta Therapeutics has announced that golodirsen will cost in parity with eteplirsen, another medication of a similar kind, which may be as high as US$300,000 per year. Also, the accelerated approval of golodirsen has paved the way for people to have early access to the medication, at the same time, it is shrouded with controversy over a number of issues. A double-blind placebo-controlled confirmatory trial (NCT02500381) is ongoing to resolve the issues.
The Orange Box features five complete games compiled into one retail unit: Half-Life 2 and its two continuations, Episode One and Episode Two; Portal; and Team Fortress 2. All of these games use Valve's Source engine. At its launch the game was priced similar to other AAA video game releases of the era, with it costing $49.95 on PC and $59.95 on console in the United States. The PC release has each game as separate launchables, while the console versions have a main menu where the five games can be selected. Through the Steam platform for the Windows version, the games can collect and report in-depth data such as where the player's character died, completion time, and total victories in multiplayer modes. This data is compiled to generate gameplay statistics for Episode One, Episode Two, and Team Fortress 2. Although Half-Life 2 has the largest proportion of Achievements, there are 99 spread across all five games, exceeding the 50-Achievement limit that Microsoft maintains to feature the most Achievements of any Xbox 360 product. These Achievements include killing a certain number of monsters, finding hidden weapon caches, or other tasks specific to each game. All the games on The Orange Box except Half-Life 2 (on consoles and on PC prior to its 2024 20th anniversary update) contain in-game commentary that can be enabled, allowing the player to listen to the developers discuss the creation and purpose of particular sections and components of each game.
Sources: en.wikipedia.org
=== Infraclass Neopterygii === Neopterygians are the second major occurrence in the evolution of ray-finned fish and today include the majority of modern bony fish. They are distinguished from their earlier ancestors by major changes to the jaws, shape of the skull, and tail. They have three divisions:
Functional amyloid in Homo sapiens: Intralumenal domain of melanocyte protein PMEL Peptide/protein hormones stored as amyloids within endocrine secretory granules in the pituitary gland Receptor-interacting serine/threonine-protein kinase 1/3 (RIP1/RIP3) Fragments of prostatic acid phosphatase and semenogelins Functional amyloid in other organisms: Curli fibrils produced by E. coli, Salmonella, and a few other members of the Enterobacteriales (Csg). The genetic elements (operons) encoding the curli system are phylogenetic widespread and can be found in at least four bacterial phyla. This suggest that many more bacteria may express curli fibrils. GvpA, forming the walls of particular Gas vesicles, i.e. the buoyancy organelles of aquatic archaea and eubacteria Fap fibrils in various species of Pseudomonas Chaplins from Streptomyces coelicolor Spidroin from Trichonephila edulis (spider) (Spider silk) Hydrophobins from Neurospora crassa and other fungi Fungal cell adhesion proteins forming cell surface amyloid regions with greatly increased binding strength Environmental biofilms according to staining with amyloid specific dyes and antibodies. Tubular sheaths encasing Methanosaeta thermophila filaments Functional amyloid acting as prions Several yeast prions are based on an infectious amyloid, e.g. [PSI+] (Sup35p); [URE3] (Ure2p); [PIN+] or [RNQ+] (Rnq1p); [SWI1+] (Swi1p) and [OCT8+] (Cyc8p) Prion HET-s from Podospora anserina Neuron-specific isoform of CPEB from Aplysia californica (marine snail)
The basal surface of epithelial tissue rests on a basement membrane and the free, apical, or apex surface faces body fluid or the outside. The basement membrane acts as a scaffolding on which epithelium can grow and regenerate after injuries, and comprises the basal lamina and reticular lamina; although, some older sources use basement membrane and basal lamina synonymously. The basement membrane acts as a selectively permeable membrane that determines which substances will be able to enter the epithelium, as epithelial tissue has a nerve supply though no blood supply. There are three principal shapes of epithelial cell: squamous (scaly), columnar, and cuboidal. Transitional epithelium has cells that can change from squamous to cuboidal, depending on the amount of tension on the epithelium. Epithelial tissue can be further categorised as having a singular layer of cells as simple epithelium; or as layers of two or more cells deep as stratified epithelium—stratified squamous epithelium, stratified cuboidal epithelium, and stratified columnar epithelium. When taller simple columnar epithelial cells are viewed in cross section showing several nuclei appearing at different heights, they can be confused with stratified epithelia, and are thus termed as pseudostratified columnar epithelium. Epithelial cells are often ciliated. Stratified epithelia be further divided into keratinised, parakeratinised, and transitional epithelia or urothelia.
=== Anions and cations === Cations including sodium, potassium, calcium, and magnesium are common in industrial water supplies. Common anions include chloride, sulfate, and bicarbonate. Several methods are used to remove ions from input water supplies including reverse osmosis, distillation, and/or ion exchange. Distillation can be used to remove non-volatile metal cations and was historically used for water purification. However, distillation is energy-intensive compared to the combination of reverse osmosis and ion exchange which are more common in modern systems.
Sources: en.wikipedia.org
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.
No. SR9009 is frequently mislabeled as a SARM in online discussions, but it does not target androgen receptors. Its known mechanism involves REV-ERB nuclear receptors and circadian-metabolic gene regulation.
Human clinical data are very limited. There is no approved human use, and safety and efficacy in people are not established. Most evidence comes from preclinical models, so effects observed in animals may not apply to humans.
It is a synthetic REV-ERB agonist used mainly in preclinical research. It is not an approved medicine for human use.