A practical reference on circadian rhythm: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-02-19 and is reviewed periodically as new material appears.
SR9009 is a synthetic small molecule studied as an agonist of REV-ERB nuclear receptors. REV-ERB alpha and REV-ERB beta help regulate circadian rhythms and metabolic gene expression. In laboratory research, SR9009 has been used to probe how these receptors affect skeletal muscle, liver, and adipose tissue. The compound was identified in academic drug-discovery work and is often described in scientific literature by its chemical name and research code. It is not an approved medicine, and human clinical data remain limited or absent.
SR9009 binds REV-ERB receptors and alters their repressive activity on target genes. This action can change transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. In rodent studies, treated animals have shown changes in muscle oxidative capacity and exercise performance, though effects vary by dose, duration, and model. The precise molecular steps connecting receptor binding to whole-body outcomes are still an active area of investigation. Findings in animals do not automatically translate to humans.
Research interest in SR9009 grew from studies of circadian biology and metabolic disease. Preclinical reports describe effects on exercise capacity, muscle metabolism, and blood lipid levels in rodents, but these findings come from controlled laboratory settings. The compound has low oral bioavailability in animals, which limits systemic exposure after swallowing. Investigators often use injected routes in experiments to achieve measurable plasma concentrations. Human clinical data are sparse, no approved therapeutic product exists, and whether animal effects translate to humans remains an open question.
Regulatory and sporting contexts treat SR9009 as a prohibited substance in many elite competitions. Its presence on banned lists reflects concerns about performance enhancement and unknown long-term safety. Analytical chemists have developed methods to detect the parent compound and its metabolites in urine and blood. Literature discussions distinguish between in vitro potency, animal pharmacology, and anecdotal human reports. The latter are difficult to verify because products sold online may lack purity or contain different compounds.
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, lipid metabolism, and inflammatory gene expression. In cell and animal experiments, SR9009 alters transcription of clock-controlled genes and metabolic pathways. The compound is not a hormone and does not resemble classical steroid structures. Its activity depends on binding to the ligand-binding domain of REV-ERB, where it can modify corepressor recruitment.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic REV-ERB agonist | Small-molecule nuclear receptor ligand |
| Appearance | Off-white to pale yellow solid | Typical for research-grade powder |
| Solubility class | Soluble in DMSO; low water solubility | Common stock solutions use organic solvent |
| Typical stock solvent | Dimethyl sulfoxide | Used for laboratory assays |
| Common analytical method | HPLC with UV or mass detection | Used for identity and purity checks |
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.
SR9009 is a synthetic small molecule studied as a REV-ERB agonist. REV-ERBα and REV-ERBβ are nuclear receptors that help regulate circadian rhythms and metabolic gene expression. The compound was identified in academic screening efforts to find synthetic ligands for these receptors. In cell and animal studies, SR9009 alters transcription of genes involved in lipid and glucose metabolism, and it can shift circadian behavior. It is not an approved therapeutic agent.
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 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.
SR9009 is a synthetic small molecule that acts on the nuclear receptors REV-ERBα and REV-ERBβ. These receptors are part of the circadian clock machinery and normally repress transcription of certain target genes. In laboratory research, SR9009 is used as a chemical tool to study how REV-ERB activity influences metabolism, inflammation, and daily biological rhythms. The compound is not an approved medicine, and its effects in humans remain largely uncharacterized. It is often described as an investigational agent rather than a therapeutic product.
Regulatory treatment of SR9009 varies by country and region. It is not approved as a pharmaceutical, and several jurisdictions restrict its sale for human consumption. Some authorities classify it as a research chemical, a prescription-only substance, or a prohibited performance-enhancing agent in sport. Purchasers may encounter certificates of analysis, but these documents do not guarantee identity, purity, or legality. In research settings, institutional safety reviews and controlled procurement help ensure that materials are handled under appropriate oversight. The absence of harmonized rules means that legal status can change and requires verification.
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.
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.
Several misconceptions surround SR9009. It is often described as a SARM, a steroid, or an exercise pill, but its known target is the REV-ERB receptor family. Rodent studies have examined exercise capacity and metabolic markers, yet human outcomes remain unproven. Oral bioavailability appears low in animals, and human pharmacokinetics are not well characterized. Online products may contain impurities or different compounds, so identity and purity testing are important for research use.
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.
Emmanuelle Charpentier and Jennifer A Doudna won the 2020 prize in chemistry “for the development of a method for genome editing.” Charpentier and Doudna are the first women to share the Nobel Prize in chemistry.
== Etymology == William C. Boyd alone and then together with Elizabeth Shapleigh introduced the term "lectin" in 1954 from the Latin word lectus, "chosen" (from the verb legere, to choose or pick out).
=== Menopause === The end of ovulation and the beginning of menopause can result in hyperandrogenism. During this transition, the body stops releasing estrogen at a faster rate than it stops releasing androgens. In some cases, the difference between the lower estrogen levels and higher androgen levels can produce hyperandrogenism. A decrease in sex hormone levels while the free androgen index increases can also contribute to this process.
Military Engineer Services (Urdu: ایم ای ایس, "MES") is an inter-service organization of the Ministry of Defence responsible primarily for engineering and construction services for the Pakistan Armed Forces, including the Army, Navy, Airforce and the Ministry of Defense Production. Furthermore, it is involved in complex construction projects including hospitals, buildings, workshops, roads etc.
Sources: en.wikipedia.org
In the mobilization stage, the stepparent can begin to step forward to address the family's process and structure. The tasks of this stage are to confront differences in each member's perception of the new family, as well as to influence one another before shaming or blaming begins to take action to reorganize the family structure. The goal here is to make joint decisions about new stepfamily rituals, rules, and roles. The focus in this stage is on the stepfamily's unique "middle ground" (i.e. the "areas of shared experience, shared values, and easy cooperative functioning created over time"), and on balancing this new middle ground with honoring of past and other relationships. The later stages consist of the contact and resolution stages. In the contact stage, the couple is working well together, the boundaries between households are clear, and stepparents have definite roles with stepchildren as "intimate outsiders." The task for this stage is in solidifying the stepparent's role, and in continuing the process of awareness. Finally, in the resolution stage, the stepfamily's identity has become secure. The family accepts itself for who it is, there is a strong sense of the stepfamily's middle ground, and children feel secure in both households. The task for this stage is to nourish the depth and maturity gained through this process, and to rework any issues that might arise at family "nodal events" (e.g., weddings, funerals, graduations, etc.).
== Signs and symptoms == Hallmark symptoms of ciguatera in humans include gastrointestinal, cardiovascular, and neurological effects. Gastrointestinal symptoms include nausea, vomiting, and diarrhea, usually followed by neurological symptoms such as headaches, muscle aches, numbness of the extremities, mouth and lips, reversal of hot and cold sensation, ataxia, vertigo, and hallucinations. Severe cases of ciguatera can also result in cold allodynia, which is a burning sensation on contact with cold. Neurological symptoms can persist and ciguatera poisoning is occasionally misdiagnosed as multiple sclerosis. Cardiovascular symptoms include bradycardia, tachycardia, hypotension, hypertension, orthostatic tachycardia, exercise intolerance, and abnormal electrocardiograms. Death from the condition can occur, but is very rare. Dyspareunia and other ciguatera symptoms have developed in otherwise healthy males and females following sexual intercourse with partners suffering ciguatera poisoning, signifying that the toxin may be sexually transmitted. Diarrhea and facial rashes have been reported in breastfed infants of poisoned mothers, suggesting that the polyether toxins partition into breast milk. The symptoms can last from weeks to months, and in extreme cases as long as 20 years, often leading to long-term disability. Most people do recover slowly over time, but genetically susceptible individuals are not able to remove the toxin and will remain sick indefinitely without medical treatment
=== Pharmacodynamics === Tavapadon acts as a highly selective partial agonist of the dopamine D1 receptor (Ki = 9 nM; IATooltip Intrinsic activity = 65%) and the dopamine D5 receptor (Ki = 13 nM; IA = 81%). It has no significant affinity or functional activity at the D2-like receptors (D2, D3, D4) (Ki ≥ 4,870 to 6,720 nM). Tavapadon also shows biased agonism for Gs-coupled signaling at the D1-like receptors.
== Rise to prominence (1970–1976) == In 1971, Mahathir announced his plan to rejoin UMNO, stating he would make a formal statement at an appropriate time; that same year, he also met Prime Minister Abdul Razak Hussein during a visit to Morib. Mahathir rejoined UMNO on 7 March 1972. Recognizing his potential and sharp political acumen, Razak appointed Mahathir as a Senator for Kedah in 1973. Around the same time, Mahathir also became the chairman of Food Industries of Malaysia (FIMA) Sdn. Bhd. In January 1973, as chairman of the FIMA, Mahathir visited a government factory in Pekan Nanas. He faced peaceful protests from over 200 workers demanding better working conditions and wage improvements. After Mahathir spoke to the workers and promised to review their grievances, they dispersed peacefully. He remained chairman of FIMA until 1981, when he became prime minister and was succeeded by Basir Ismail. Mahathir rose quickly in the Abdul Razak government, returning to UMNO's Supreme Council in 1973. He returned to the House of Representatives in the 1974 election, winning the Kedah-based seat of Kubang Pasu unopposed. He was appointed to Cabinet in September 1974 as the Minister for Education. During his tenure, Mahathir rolled out a new school curriculum for both primary and secondary schools, designed to provide holistic education and cultivate well-rounded individuals. Around this time, he also ceased his private medical practice. In 1975, Mahathir ran for one of the three vice-presidencies of UMNO.
==== Blue Dream ==== Blue Dream is a hybrid cannabis strain widely used for both medical and recreational purposes, developed in 2003 through mixing Sativa and Indica strains named Blueberry and Haze. Believed to have originated in California, the plants will typically grow within 9-10 weeks, with moderate to high yields.
Sources: en.wikipedia.org
fermentation Any anaerobic metabolic pathway in which organic molecules such as glucose or other carbohydrates are catabolized in the absence of oxygen in order to produce ATP; or, in the broadest sense, any catabolic process in which organic compounds serve as both electron donors and acceptors. This definition distinguishes fermentation from aerobic respiration, where inorganic diatomic oxygen (O2) is the terminal electron acceptor, and from some types of anaerobic respiration. Fermentation encompasses hundreds of different redox pathways which start and end with a huge variety of reactants and end-products, often branching from various steps in glycolysis, with the most common fermentation products being lactate, acetate, ethanol, succinate, propionate, butyrate, carbon dioxide (CO2), and diatomic hydrogen (H2). It occurs in both prokaryotes and eukaryotes in conditions where exogenously supplied electron acceptors are unavailable, especially in oxygen-poor environments. Fermentation yields the equivalent of just 2 to 5 ATP per molecule of glucose, making it much less efficient than aerobic respiration, which can yield as much as 32 ATP per molecule of glucose. In multicellular organisms that primarily rely on aerobic respiration, such as animals, it is often employed as a contingency pathway; the term anaerobic glycolysis refers to the diversion of glycolysis intermediates to fermentation pathways when tissues cannot keep up with the demand for ATP due to insufficient oxygen supply.
do not correspond to mutations and can be left unfilled. In addition to these counts, data on the mutability and the frequency of the amino acids was obtained. The mutability of an amino acid is the ratio of the number of mutations it is involved in and the number of times it occurs in an alignment. Mutability measures how likely an amino acid is to mutate acceptably. Asparagine, an amino acid with a small polar side chain, was found to be the most mutable of the amino acids. Cysteine and tryptophan were found to be the least mutable amino acids. The side chains for cysteine and tryptophan have less common structures: cysteine's side chain contains sulfur which participates in disulfide bonds with other cysteine molecules, and tryptophan's side chain is large and aromatic. Since there are several small polar amino acids, these extremes suggest that amino acids are more likely to acceptably mutate if their physical and chemical properties are more common among alternative amino acids.
where K is an optical constant and c is the solution concentration. Using a differential refractometer (DRI) to measure the concentration of the solution, an absolute molar mass can be calculated. More accurate measurements can be made by using a low-angle static light scattering (LALS) detector, which operates at a very low angle and therefore do not require angular effects to be corrected. However, these detectors are very sensitive to particles, which leads to noisy data and are therefore rarely used. LALS detectors have largely been replaced by MALS detectors, which measures scattered light at multiple angles simultaneously and extrapolates the data to θ = 0° to obtain a weight-average molar mass. The coupling of SEC with MALS detection have become the benchmark for the determination of absolute molecular mass, particularly averages masses and distributions. Viscometry detectors, although less common, also function as detectors of absolute molar mass. Unlike light scattering photometers which do not use a calibration curve, viscometers apply a universal calibration curve where the logarithm of intrinsic viscosity multiplied by molar mass can be plotted against the retention volume from SEC. This method is effective for calculating the absolute molar mass of a wide variety of polymers, including rod-like polymers and dendrimers. Several other methods of analysis are used to determine the absolute molar mass.
Historically, while the late Carboniferous-early Permian lizard-like reptile group Araeoscelidia, which are (generally) morphologically diapsid, were considered to be the earliest representatives of the clade Diapsida, phylogenetic studies from the 2020s has brought into serious doubt their relationship with other diapsids (Neodiapsida), and they have been found as very early diverging branch of Reptilia or even outside of Reptilia entirely. Turtles have been traditionally believed to be surviving parareptiles, on the basis of their anapsid skull structure, which was assumed to be primitive trait. The rationale for this classification has been disputed, with some arguing that turtles are diapsids that evolved anapsid skulls, improving their armor. Later morphological phylogenetic studies with this in mind placed turtles firmly within Diapsida. All molecular studies have strongly upheld the placement of turtles within diapsids, most commonly as a sister group to extant archosaurs.
The Bloomin' Onion is a signature Outback item, though it is not an Australian item and is not typically sold in Australia apart from at this chain. It is a 1 pound (500 g) onion cut to 'bloom' open, breaded, deep-fried and served with mayonnaise-horseradish sauce. Other restaurants offer items similar to the Bloomin' Onion, as in Chili's Awesome Blossom (discontinued), Texas Roadhouse's Cactus Blossom, and Lone Star Steakhouse & Saloon's Texas Rose. Many of the Bloomin' Onions have come under fire for high-calorie counts, sometimes going over 1,500 calories.
Sources: en.wikipedia.org
SR9009 is a synthetic research compound that acts on REV-ERB nuclear receptors. It is not approved for human use and is sold only as a research chemical. Its effects have been studied mainly in cells and rodents.
It binds REV-ERB alpha and REV-ERB beta and changes the expression of genes tied to metabolism and circadian rhythm. These changes can affect mitochondria and energy use in animal models. The exact chain from receptor binding to physiological outcome is still being mapped.
No reliable human trials show that SR9009 improves athletic performance. Some rodent studies report endurance changes, but these results are not proof of human benefit. Its use in sport is prohibited, and quality and safety data are lacking.
SR9009 is a synthetic small molecule studied as an agonist of the REV-ERB nuclear receptors. It is not an approved medicine, and its effects in humans are not well characterized.