The short version of nuclear receptor fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-02-15. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Not approved as a medicine in major jurisdictions | Sold as a research chemical; legal status varies |
| Anti-doping status | Prohibited by the World Anti-Doping Agency | Listed under non-approved substances or related category |
| Typical analytical method | LC-MS/MS | Used for detection and confirmation in biological samples |
| Storage temperature | −20 °C or lower for solid | Desiccated and protected from light |
| Common solution solvents | DMSO; ethanol | Aqueous solubility is limited |
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.
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.
Spindle cell sarcoma is a type of connective tissue cancer. The tumors generally begin in layers of connective tissue, as found under the skin, between muscles, and surrounding organs, and will generally start as a small, inflamed lump, which grows in size. At first, the lump is, small in size, as the tumor exists in stage 1, and will not necessarily expand beyond its encapsulated form. However, it may develop cancerous traits that can only be detected through microscopic examination or cell-level molecular analysis. As such, at Stage 1, the tumor is usually treated by excision, which includes wide margins of healthy-looking tissue, followed by thorough biopsy, and additional excision, if necessary. The prognosis for a stage 1 tumor excision is usually fairly optimistic, but if the tumor progresses to levels 2 and 3, prognosis worsens, due to tumor cells' likely having spread to other parts of the body, including nearby healthy tissues, or to system-wide locations that include the lungs, kidneys, and liver. In these cases, prognosis is grim and chemotherapy and radiation are the only methods of controlling the cancer. A variety of factors influence the incidence of spindle cell sarcoma, including genetic predisposition, but it may also be caused by a combination of other factors, including injury and inflammation in patients who are already thought to be predisposed to such tumors. Normal spindle cells are a naturally occurring part of the body's response to injury.
Nonetheless, there are indications that the Greeks had an open mind about large penises. A statue of the god Hermes with an exaggerated penis stood outside the main gate of Athens and in Alexandria in 275 BC, a procession in honor of Dionysus hauled a 180-foot phallus through the city and people venerated it by singing hymns and reciting poems. The Romans, in contrast to the Greeks, seem to have admired large penises and many large phalli have been recovered from the ruins of Pompeii. Depictions of Priapus were very popular in Roman erotic art and literature. Over eighty obscene poems dedicated to him have survived. Penis size is alluded to in the Bible:
=== Chronic disease === Individuals who have cirrhosis or chronic liver disease may develop gynecomastia for several reasons. Those diagnosed with cirrhosis tend to have increased secretion of the androgenic hormone androstenedione from the adrenal glands, increased conversion of this hormone into various types of estrogen, and increased levels of SHBG, which leads to decreased blood levels of free testosterone. Around 10–40% of males with Graves' disease (a common form of hyperthyroidism) experience gynecomastia. Increased conversion of testosterone to estrogen by increased aromatase activity, increased levels of SHBG and increased production of testosterone and estradiol by the testes due to elevated levels of LH cause the gynecomastia. Proper treatment of the hyperthyroidism can lead to the resolution of the gynecomastia.
Sources: en.wikipedia.org
Ac-SDKP (Thymosin Beta 4 Fragment (1–4), Goralatide) is an endogenous tetrapeptide derivative that is the N-acetylated derivative of the fragment composed of amino acids 1-4 derived from cleavage of the N-terminus of the signalling factor thymosin beta-4 by the enzyme prolyl oligopeptidase. It is a selective inhibitor of haematopoietic cell proliferation and has antiinflammatory, anti-fibrotic, and pro-angiogenic properties, with particular applications in preventing the development of kidney fibrosis and cardiac fibrosis following injury to these organs. Adamax BPC-157 CJC-1295 KPV tripeptide TB-500
Xenon-135 is a radioactive isotope of xenon, produced as a fission product of uranium. It has a half-life of 9.14 hours and is the most powerful known neutron-absorbing nuclear poison (having a neutron absorption cross-section of about 2 million barns). The overall yield of xenon-135 from fission is 6.3%, without considering any loss by neutron capture. 135Xe exerts a significant effect on nuclear reactor operation (xenon pit). It is discharged to the atmosphere in small quantities by some nuclear power plants.
In 2009, more than 18,000 votes were cast in a BBC poll to find the UK's favourite poet; Thomas was placed 10th. Several of his poems have passed into the cultural mainstream, and his work has been used by authors, musicians and film and television writers. The BBC Radio programme Desert Island Discs, in which guests usually choose their favourite songs, has heard 50 participants select a Dylan Thomas recording. John Goodby states that this popularity with the reading public allows Thomas's work to be classed as vulgar and common. Goodby also cites that, despite a brief period during the 1960s when Thomas was considered a cultural icon, the poet has been marginalized in critical circles due to his exuberance, in both life and work, and his refusal to know his place. Goodby believes that Thomas has been mainly snubbed since the 1970s and has become "... an embarrassment to twentieth-century poetry criticism", his work failing to fit standard narratives and thus being ignored rather than studied. In June 2022, Thomas was the subject of BBC Radio 4's In Our Time.
Sources: en.wikipedia.org
The official logo and brand identity of the tournament was unveiled on May 17, 2023, at the Griffith Observatory in Los Angeles, California. The logo's basic form consisted of a stacked "26" with an image of the FIFA World Cup Trophy in front of it. This was the first time that the trophy was depicted in a World Cup emblem as a photo, as opposed to a stylized representation. Initial reactions to the logo were largely negative, with many saying that the design felt unfinished or uncreative compared to the stylistic logos of past FIFA World Cup tournaments. The next day, FIFA unveiled brand identities for each host city, which incorporated designs that reflected local landscapes or culture.
=== Mass spectrometry === In mass spectrometry of peptides and proteins, knowledge of the masses of the residues is useful. The mass of the peptide or protein is the sum of the residue masses plus the mass of water (Monoisotopic mass = 18.01056 Da; average mass = 18.0153 Da). The residue masses are calculated from the tabulated chemical formulas and atomic weights. In mass spectrometry, ions may also include one or more protons (Monoisotopic mass = 1.00728 Da; average mass* = 1.0074 Da). *Protons cannot have an average mass, this confusingly infers to Deuterons as a valid isotope, but they should be a different species (see Hydron (chemistry))
=== Pharmacokinetics === Four primary metabolic pathways of 3-HO-PCP have been identified. These include piperidine hydroxylation, N-dealkylation, O-glucuronidation, and O-sulfate-conjugation. In urine samples, the N-dealkylated-COOH metabolite was the main metabolite detected. Although it was hypothesized that 3-HO-PCP might be a metabolite of PCP in humans, there is no evidence that this is the case. 3-HO-PCP is a metabolite of 3-MeO-PCP.
B lymphocytes (B cells), which are part of the normal immune response, are also responsible for the over-aggressive response seen in autoimmune diseases like systemic lupus erythematosus. B cells develop in the bone marrow and continue to mature peripherally in secondary lymphoid organs and in the gut. When autoimmune B cells attack the body's own tissues, they are normally destroyed by cell suicide (apoptosis). Researchers theorize that systemic lupus erythematosus is caused when autoimmune B cells proliferate and survival factors protect them from cell suicide. B-cell activating factor (BAFF), also called B-lymphocyte stimulator (BLyS), is required for the development and survival of B cells. In systemic lupus erythematosus patients, BAFF is overexpressed, which may cause autoimmune B cell proliferation and survival. Belimumab binds to BAFF and prevents it from binding to B cells. Without BAFF, B cells commit suicide and no longer contribute to the autoimmune damage of systemic lupus erythematosus. BAFF is secreted by a variety of cells: monocytes and macrophages; bone marrow stromal cells; astrocytes in certain glioblastomas; synoviocytes in rheumatoid arthritis; and salivary epithelial cells in Sjögren syndrome. It interacts with three membrane receptors on B lymphocytes:
Sources: en.wikipedia.org
Its legal status depends on the country and intended use. It is not an approved medicine in major jurisdictions. In sport, it is prohibited by anti-doping rules.
Laboratories typically use LC-MS/MS to detect SR9009 and related compounds in urine or blood. The method is sensitive but depends on sample collection timing. Confirmatory analysis follows quality-control procedures.
Solid material is generally kept cold, dry, and protected from light. Solutions are often stored in sealed containers at low temperature. Stability beyond recommended periods is not well documented.
Liquid chromatography with mass spectrometry is a common approach. Ultraviolet detection and nuclear magnetic resonance can support identification when suitable standards are available.