If you have been reading about bioavailability and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-09-16. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
REV-ERB proteins help regulate daily cycles in gene expression, including genes tied to lipid and glucose metabolism. SR9009 binds these receptors and alters their activity in cell and animal experiments. Consequences observed in rodents include changes in skeletal muscle oxidative capacity, blood lipid levels, and exercise performance. The precise chain from receptor occupancy to whole-body effects is still an active area of study. Human responses cannot be assumed from rodent data.
Most published work on SR9009 consists of preclinical studies. It is widely sold as a research chemical, a category that does not imply safety, efficacy, or pharmaceutical-grade quality. Sports anti-doping organizations have listed SR9009 as a prohibited substance, and its presence in an athlete sample can lead to sanctions. Legal status differs by country; in several jurisdictions it is not approved for human consumption and may be treated as an unapproved new drug.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic REV-ERB agonist | Small-molecule ligand; not a hormone or peptide |
| Molecular formula | C20H24ClN3O4S | Reported for the free base |
| CAS Registry Number | 1379686-30-2 | Unique chemical identifier |
| Common synonyms | SR9009; stenabolic | Stenabolic is informal and not an official name |
| Reported targets | REV-ERBα and REV-ERBβ | Nuclear receptors linked to circadian and metabolic regulation |
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.
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.
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.
Biohazardous safety issues are identified with specified labels, signs and paragraphs established by the American National Standards Institute (ANSI). Today, ANSI Z535 standards for biohazards are used worldwide and should always be used appropriately within ANSI Z535 Hazardous Communications (HazCom) signage, labeling and paragraphs. The goal is to help workers rapidly identify the severity of a biohazard from a distance and through colour and design standardization. Biological hazard symbol design:
Pyzdek, T, "Quality Engineering Handbook", 2003, ISBN 0-8247-4614-7 De Feo, J. A., "Juran's Quality Handbook", 2016, ISBN 978-1-25964-361-3 ASTM E105 Standard Practice for Probability Sampling of Materials ASTM E122 Standard Practice for Calculating Sample Size to Estimate, With a Specified Tolerable Error, the Average for Characteristic of a Lot or Process ASTM E141 Standard Practice for Acceptance of Evidence Based on the Results of Probability Sampling ASTM E1402 Standard Terminology Relating to Sampling ASTM E1994 Standard Practice for Use of Process Oriented AOQL and LTPD Sampling Plans ASTM E2234 Standard Practice for Sampling a Stream of Product by Attributes Indexedby AQL Sampling procedures for inspection by attributes, ISO 2859-1:1999 Sampling procedures for inspection by attributes, JIS Z 9015-1:2006 Acceptance Sampling Calculators (SQC Online) (A subscription fee is required to use the calculators. The "free" calculations have locked features.)
The Tandem Diabetes Care t:Slim X2 was approved by the U.S. Food and Drug Administration in 2019 and is the first insulin pump to be designated as an alternate controller enabled (ACE) insulin pump. ACE insulin pumps allow users to integrate continuous glucose monitors, automated insulin dosing (AID) systems, and other diabetes management devices with the pump to create a personalized diabetes therapy system. Many users of the t:slim X2 integrate the pump with the Dexcom G6, a continuous glucose monitor approved by the FDA in 2018. It was the first CGM authorized for use in an integrated therapy system. The device does not require fingerstick calibrations.
The permeability of a membrane is the rate of passive diffusion of molecules through the membrane. These molecules are known as permeant molecules. Permeability depends mainly on the electric charge and polarity of the molecule and to a lesser extent the molar mass of the molecule. Due to the cell membrane's hydrophobic nature, small electrically neutral molecules pass through the membrane more easily than charged, large ones. The inability of charged molecules to pass through the cell membrane results in pH partition of substances throughout the fluid compartments of the body. Lipids, Membranes and Vesicle Trafficking – The Virtual Library of Biochemistry and Cell Biology Cell membrane protein extraction protocol Membrane homeostasis, tension regulation, mechanosensitive membrane exchange and membrane traffic 3D structures of proteins associated with plasma membrane of eukaryotic cells Lipid composition and proteins of some eukariotic membranes Prokaryotic and Eukaryotic Cells
Sources: en.wikipedia.org
From 2002 to 2004, Pinhasov carried out postdoctoral research at Johnson & Johnson Pharmaceutical Research and Development (Spring House, Pennsylvania, United States), where under the guidance of Dr. Douglas Brenneman he was engaged in the development of drugs for the treatment of neurodegenerative diseases. In 2005, Pinhasov joined the Department of Molecular Biology at Ariel University (formerly the College of Judea and Samaria) as an assistant professor. He was Head of the department from 2008 to 2014. In 2014, Pinhasov was appointed Vice-President and Dean of Research & Development at Ariel University, holding this position until 2020. In 2020 the Senate of Ariel University elected Professor Pinhasov as the Rector of Ariel University, succeeding Professor Michael Zinigrad, who held this office for 12 years. In September 2023, in recognition of his contribution to academic ties between Israel and Kazakhstan, the Senate of Astana Medical University (AMU) awarded Prof. Albert Pinhasov the title of honorary professor.
HCl(aq) + NaOH(aq) → H2O(l) + NaCl(aq) Neutralization is the basis of titration, where a pH indicator shows equivalence point when the equivalent number of moles of a base have been added to an acid. It is often wrongly assumed that neutralization should result in a solution with pH 7.0, which is only the case with similar acid and base strengths during a reaction. Neutralization with a base weaker than the acid results in a weakly acidic salt. An example is the weakly acidic ammonium chloride, which is produced from the strong acid hydrogen chloride and the weak base ammonia. Conversely, neutralizing a weak acid with a strong base gives a weakly basic salt (e.g., sodium fluoride from hydrogen fluoride and sodium hydroxide).
The removal of dead cells by neighboring phagocytic cells has been termed efferocytosis. Dying cells that undergo the final stages of apoptosis display apoptotic-cell associated molecular patterns (ACAMPs), such as phosphatidylserine on the outer leaflet of the cell membrane. Phosphatidylserine is normally found on the inner leaflet surface of the plasma membrane, but is redistributed during apoptosis to the extracellular surface by a protein known as scramblase. These molecules mark the cell for phagocytosis by cells possessing the appropriate receptors, such as macrophages. The removal of dying cells by phagocytes occurs in an orderly manner without eliciting an inflammatory response. During apoptosis cellular RNA and DNA are separated from each other and sorted to different apoptotic bodies; separation of RNA is initiated as nucleolar segregation.
While APHL primarily focuses on public health laboratories in the United States, their global health program makes an effort to help other countries strengthen their own laboratory practices.APHL works with more than 30 countries to: Share effective testing procedures Develop laboratory policies Improve the quality of data Train laboratory leaders Utilize information management systems Create strategies to monitor and detect Establish emergency response programs Design training programs APHL also works with public health laboratories around the world to share information on global health crises and promotes cross-border collaboration.
5-HT2C receptor agonists reduce appetite by working on serotonin receptors in a region of the brain called the hypothalamus. Lorcaserin (Belviq) was FDA approved for weight loss but was withdrawn from the market because a safety clinical trial shows an increased occurrence of cancer. Cannabinoid receptor antagonists were developed to treat obesity because researchers noticed that cannabinoid agonists (such as THC, the main pharmacologically active component of cannabis), increased appetite. However, some drugs in this class such as rimonabant were withdrawn or ceased development due to concerns about mental health and suicide. More selective drugs—some are in development that act only in peripheral tissues, not the brain—may be able to achieve this result with fewer adverse effects. GLP-1 agonists such as tirzepatide, semaglutide, and liraglutide slow gastric emptying and also have neurologically driven effects on appetite. It is unknown if GLP-1 agonists or dual/triple agonists of GLP-1 and/or the glucagon or GIP receptors act solely by reducing energy intake or if they also increase energy expenditure. Setmelanotide is an agonist of the melanocortin 4 receptor and is used in people with certain rare genetic conditions that cause obesity. It is less effective and not approved for general obesity.
Sources: en.wikipedia.org
the carboxylation of glutamate allows for better binding of calcium cations, Hydroxyproline, generated by hydroxylation of proline, is a major component of the connective tissue collagen. Hypusine in the translation initiation factor EIF5A, contains a modification of lysine. Some non-proteinogenic amino acids are not found in proteins. Examples include 2-aminoisobutyric acid and the neurotransmitter gamma-aminobutyric acid. Non-proteinogenic amino acids often occur as intermediates in the metabolic pathways for standard amino acids – for example, ornithine and citrulline occur in the urea cycle, part of amino acid catabolism (see below). A rare exception to the dominance of α-amino acids in biology is the β-amino acid beta alanine (3-aminopropanoic acid), which is used in plants and microorganisms in the synthesis of pantothenic acid (vitamin B5), a component of coenzyme A.
Not much is known about the mutations in the genes OBS1and CCD8 and their function in growth and development so far. However, the implications of 3M syndrome suggest that both these genes encode for proteins that play a role in the CUL7 ubiquination pathway. Due to the fact that many of the abnormalities associated with this disorder are congenital, the presence of these clinical features at birth is usually sufficient to make the diagnosis. Diagnosis is suggested in children with the following: low birth weight, severe growth retardation, typical facial features, and characteristic radiological findings. In some cases, growth retardation and/or other characteristic findings suggestive of Three M syndrome may be detected before birth by ultrasound. In fetal ultrasonography, reflected sound waves are used to create an image of the developing fetus.
Amyloid beta (Aβ, Abeta or beta-amyloid) denotes peptides of 36–43 amino acids that are the main component of the amyloid plaques found in the brains of people with Alzheimer's disease. The peptides derive from the amyloid-beta precursor protein (APP), which is cleaved by beta secretase and gamma secretase to yield Aβ in a cholesterol-dependent process and substrate presentation. Both neurons and oligodendrocytes produce and release Aβ in the brain, contributing to formation of amyloid plaques. Aβ molecules can aggregate to form flexible soluble oligomers which may exist in several forms. It is now believed that certain misfolded oligomers (known as "seeds") can induce other Aβ molecules to also take the misfolded oligomeric form, leading to a chain reaction akin to a prion infection. The oligomers are toxic to nerve cells. The other protein implicated in Alzheimer's disease, tau protein, also forms such prion-like misfolded oligomers, and there is some evidence that misfolded Aβ can induce tau to misfold. A study has suggested that APP and its amyloid potential is of ancient origins, dating as far back as early deuterostomes.
Group specificity occurs when an enzyme will only react with molecules that have specific functional groups, such as aromatic structures, phosphate groups, and methyls. One example is pepsin, an enzyme that is crucial in digestion of foods ingested in our diet, that hydrolyzes peptide bonds in between hydrophobic amino acids, with recognition for aromatic side chains such as phenylalanine, tryptophan, and tyrosine. Another example is hexokinase, an enzyme involved in glycolysis that phosphorylates glucose to produce glucose-6-phosphate. This enzyme exhibits group specificity by allowing multiple hexoses (6 carbon sugars) as its substrate. Glucose is one of the most important substrates in metabolic pathways involving hexokinase due to its role in glycolysis, but is not the only substrate that hexokinase can catalyze a reaction with.
Isoforms I, III, and VIII are also stimulated by Ca2+/calmodulin. Isoforms V and VI are inhibited by Ca2+ in a calmodulin-independent manner. Isoforms II, IV and IX are stimulated by alpha subunit of the G protein. Isoforms I, V and VI are most clearly inhibited by Gi, while other isoforms show less dual regulation by the inhibitory G protein. Soluble AC (sAC) is not a transmembrane form and is not regulated by G proteins or forskolin, instead acts as a bicarbonate/pH sensor. It is anchored at various locations within the cell and, with phosphodiesterases, forms local cAMP signalling domains. In neurons, calcium-sensitive adenylyl cyclases are located next to calcium ion channels for faster reaction to Ca2+ influx; they are suspected of playing an important role in learning processes. This is supported by the fact that adenylyl cyclases are coincidence detectors, meaning that they are activated only by several different signals occurring together. In peripheral cells and tissues adenylyl cyclases appear to form molecular complexes with specific receptors and other signaling proteins in an isoform-specific manner.
Sources: en.wikipedia.org
SR9009 is a synthetic compound investigated as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is used in preclinical research on circadian rhythm and metabolism. It is not an approved drug.
No. It has no approved medical indication, and human safety and efficacy data are limited. It appears in research chemical markets and is banned by some sports authorities.
Natural ligands include heme and certain metabolites; SR9009 is a synthetic small molecule with higher potency and selectivity in some assays. Its effects depend on cell type and timing. It is not a naturally occurring compound.
It is a synthetic compound studied as an agonist of REV-ERB nuclear receptors. It is not an approved medicine and has mainly been examined in laboratory and animal research.