If you have been reading about mitochondrial biogenesis 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 2026-03-27. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Detection of SR9009 in biological samples usually relies on liquid chromatography coupled to tandem mass spectrometry. This approach separates the compound from matrix components and identifies it by mass transitions. Because SR9009 can undergo metabolism, laboratories often look for both parent drug and specific metabolites. Sample preparation may involve protein precipitation or solid-phase extraction. Method validation examines sensitivity, carryover, and interference from related substances, and reference standards are required for accurate calibration.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Typical storage temperature | -20 °C or lower | Desiccated and protected from light |
| Common analytical method | LC-MS/MS | Detects parent drug and metabolites |
| Solubility class | Lipophilic; soluble in organic solvents | Low aqueous solubility |
| Molecular weight | 437.94 g/mol | Calculated from reported formula |
| Synonyms | SR9009; REV-ERB agonist | Code name used in scientific literature |
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.
In laboratory settings, SR9009 is typically characterized by liquid chromatography–mass spectrometry (LC-MS) or high-performance liquid chromatography with ultraviolet detection (HPLC-UV). These methods can confirm identity and estimate purity, but they require reference standards for accurate quantification. Because SR9009 is not a licensed pharmaceutical, no harmonized pharmacopeial monograph exists. Laboratories often validate in-house methods for matrices such as plasma, urine, or cell culture media. Sample preparation may involve protein precipitation or liquid-liquid extraction before analysis.
Physicochemical behavior influences handling. SR9009 is described as a solid with limited aqueous solubility, so organic solvents such as dimethyl sulfoxide or ethanol are common in research stock solutions. Aqueous dilution can produce precipitates if the organic content is too low. Light, heat, and repeated freeze-thaw cycles may affect stability. Storage recommendations usually specify a desiccated freezer environment protected from light, but exact stability data depend on the formulation and matrix.
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.
SR9009 is supplied as a solid research chemical, often in milligram quantities. Laboratories typically weigh it in a controlled environment because fine powders can disperse. Stock solutions are commonly prepared in dimethyl sulfoxide and stored in small aliquots to reduce freeze-thaw cycles. Personal protective equipment and chemical fume hoods are standard when handling unknown or potent compounds. These practices address laboratory safety rather than human use.
Pharmacokinetic data for SR9009 are limited in published literature. Some reports indicate low oral bioavailability and rapid clearance in animals, which complicates interpretation of exposure and effect. Researchers often use injected routes in preclinical work to achieve measurable systemic levels. Analytical studies rely on mass spectrometry to detect the parent compound and its metabolites. Questions about tissue distribution, active metabolites, and long-term consequences remain open. Species differences in metabolism can affect observed half-life and target engagement.
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 and metabolic gene expression. In laboratory experiments, SR9009 binds these receptors and alters transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. It is not a naturally occurring compound and has no approved therapeutic use. Research interest stems from its ability to modify energy metabolism in cells and animal models.
In rodent studies, SR9009 has been reported to increase mitochondrial content in skeletal muscle and improve exercise endurance under some conditions. These findings led to popular descriptions such as an exercise mimetic, although that term oversimplifies the biology. Effects vary by dose, timing, tissue, and model. The compound's influence on circadian pathways means that time of administration can matter in experiments. Whether similar metabolic changes occur in humans remains largely unexplored in controlled published trials.
=== Bu === John Buchanan (1917–2007). American biochemist at MIT, best known for his research on the biosynthesis of purines. Member Natl. Acad. Sci. USA. Eduard Buchner (1860–1917). German chemist and physiologist at LMU Munich, who overthrew the doctrine of vitalism by showing that cell-free yeast extract could catalyse fermentation, a discovery described by Arthur Kornberg as the beginning of biochemistry. 1907 Nobel Prize in Chemistry. Dean Burk (1904–1988). American biochemist at the Fixed Nitrogen Research Laboratory, co-discoverer of biotin. He is credited (with Hans Lineweaver) with introducing the double-reciprocal plot in kinetics. He became a vociferous opponent of water fluoridation. Robert H. Burris (1914–2010). American biochemist at the University of Wisconsin–Madison, expert on nitrogen fixation. Member Natl. Acad. Sci. USA. Stephen Busby (DPhil 1975) FRS, biochemist at the University of Birmingham. Carlos Bustamante (b. 1951). Peruvian-American biophysicist at UC Berkeley. Known for single-molecule studies, including the use of optical tweezers for measuring the forces that maintain biological structures. Member Natl. Acad. Sci. USA.
Paleodemography studies demographic characteristics of past populations. Bioarchaeologists use paleodemography to create life tables, a type of cohort analysis, to understand demographic characteristics (such as risk of death or sex ratio) of a given age cohort within a population. It is often necessary to estimate the age and sex of individuals based on specific morphological characteristics of the skeleton.
Hilleman also developed the first Hepatitis B vaccine and the first varicella vaccine, for chickenpox. The company was incorporated in New Jersey in 1970. John J. Horan became CEO and Chairman in 1976, serving until 1985. Under his leadership, the company's investment in R&D grew threefold, and Merck became the largest pharmaceutical company in the world. In 1979, Merck scientists developed lovastatin (Mevacor), the first drug of the statin class. Merck scientist William C. Campbell and Satoshi Ōmura developed ivermectin for veterinary use in 1981, and later put it to human use against onchocerciasis in 1987–1988 with the name Mectizan; today the compound is also used against lymphatic filariasis, scabies and other parasitic infections. In 1982, the company formed a joint venture, KBI Inc., with AstraZeneca. During the late 1980s and 1990s, the company also established joint ventures with DuPont to access research and development expertise, and with Johnson & Johnson to sell over-the-counter consumer medications. In 1985, Merck received approval for imipenem, the first member of the carbapenem class of antibiotics. Antibiotics of the carbapenem class play an important role in treatment guidelines for certain hospital-acquired and multi-drug resistant infections. P. Roy Vagelos became CEO and Chairman that year, succeeding Horan. Vagelos served until reaching the company's mandatory retirement age in 1994, succeeded by Raymond Gilmartin. In 1991, Merck's Kelco subsidiary was responsible for volatile organic compound (VOC) emission pollution in the San Diego area.
== Mechanisms and functions of phosphorylation == Phosphorylation introduces a charged and hydrophilic group in the side chain of amino acids, possibly changing a protein's structure by altering interactions with nearby amino acids. Some proteins such as p53 contain multiple phosphorylation sites, facilitating complex, multi-level regulation. Because of the ease with which proteins can be phosphorylated and dephosphorylated, this type of modification is a flexible mechanism for cells to respond to external signals and environmental conditions. Kinases phosphorylate proteins and phosphatases dephosphorylate proteins. Many enzymes and receptors are switched "on" or "off" by phosphorylation and dephosphorylation. Reversible phosphorylation results in a conformational change in the structure in many enzymes and receptors, causing them to become activated or deactivated. Phosphorylation usually occurs on serine, threonine, tyrosine and histidine residues in eukaryotic proteins. Histidine phosphorylation of eukaryotic proteins appears to be much more frequent than tyrosine phosphorylation. In prokaryotic proteins phosphorylation occurs on the serine, threonine, tyrosine, histidine, arginine or lysine residues. The addition of a phosphate (PO43-) molecule to a non-polar R group of an amino acid residue can turn a hydrophobic portion of a protein into a polar and extremely hydrophilic portion of a molecule.
The observation that living things inherit traits from their parents has been used since prehistoric times to improve crop plants and animals through selective breeding. The modern science of genetics, seeking to understand this process, began with the work of the Augustinian friar Gregor Mendel in the mid-19th century.
Sources: en.wikipedia.org
=== Redox === Silver(I) salts are mild oxidants, as implicated by their role in silver-based photography and the staining of skin by silver metal upon contact with silver nitrate solutions. Characteristically, silver nitrate reacts with pieces of copper to form hairlike crystals of silver metal and a blue solution of copper nitrate:
== Function == Pancreatic polypeptide regulates pancreatic secretion activities by both endocrine and exocrine tissues. It also affects hepatic glycogen levels and gastrointestinal secretions. Its secretion in humans is increased after a protein meal, fasting, exercise, and acute hypoglycaemia, and is decreased by somatostatin and intravenous glucose. Plasma pancreatic polypeptide has been shown to be reduced in conditions associated with increased food intake and elevated in anorexia nervosa. In addition, peripheral administration of polypeptide has been shown to decrease food intake in rodents. Pancreatic polypeptide inhibits pancreatic secretion of fluid, bicarbonate, and digestive enzymes. It also stimulates gastric acid secretion. It is the antagonist of cholecystokinin and opposes pancreatic secretion stimulated by cholecystokinin. It may stimulate the migrating motor complex, synergistic with motilin. On fasting, pancreatic polypeptide concentration is 80 pg/ml; after the meal, it rises up from 8 to 10 times more; glucose and fats also induce PP's level increase, but on parenteral introduction of those substances, the level of hormones doesn't change. The administration of atropine, the vagotomy, blocks pancreatic polypeptide secretion after meals. The excitation of the vagus nerve, the administration of gastrin, secretin or cholecystokinin induce PP secretion.
The foundations for Jung's typology of psychological types were in his early research at the Burghölzli Hospital. Through the Word Association Experiment, Jung provided the first empirical evidence of "complexes", observing that individuals showed distinct patterns in how they responded to emotional disturbances: some subjects were consistently oriented toward the objective meaning of the stimulus (extraverted tendency), while others were derailed by internal, subjective associations (introverted tendency). Jung interpreted what he saw as a fundamental divergence in how psychic energy (libido) moved in psychiatric patients. He noted that in hysteria, energy flowed outward toward the object, whereas in dementia praecox (schizophrenia), energy withdrew into a subjective inner world. By 1913, Jung concluded that these were not merely symptoms of illness but exaggerated manifestations of normal psychological orientations. The further differentiation of the four psychological functions (thinking, feeling, sensation, and intuition) emerged from Jung's period of intense self-experimentation between 1913 and 1917. Documented in The Red Book (Liber Novus), Jung utilised the method of active imagination to observe his own mental processes. This introspection allowed him to map how certain functions dominate consciousness while their opposites remain "inferior" and unconscious. By comparing these personal findings with the case histories of his patients, Jung moved from a simple two-fold model (extraversion/introversion) to the complex eight-fold functional system published in 1921.
The glaucophyte chloroplast group is the smallest of the three primary chloroplast lineages as there are only 25 described glaucophyte species. Glaucophytes diverged first before the red and green chloroplast lineages diverged. Because of this, they are sometimes considered intermediates between cyanobacteria and the red and green chloroplasts. This early divergence is supported by both phylogenetic studies and physical features present in glaucophyte chloroplasts and cyanobacteria, but not the red and green chloroplasts. First, glaucophyte chloroplasts have a peptidoglycan wall, a type of cell wall otherwise only in bacteria (including cyanobacteria). Second, glaucophyte chloroplasts contain concentric unstacked thylakoids which surround a carboxysome – an icosahedral structure that contains the enzyme RuBisCO responsible for carbon fixation. Third, starch created by the chloroplast is collected outside the chloroplast. Additionally, like cyanobacteria, both glaucophyte and rhodophyte thylakoids are studded with light collecting structures called phycobilisomes.
Sources: en.wikipedia.org
Top-down proteomics is a method of protein identification capable of identifying and quantitating unique proteoforms through the analysis of intact proteins. The name is derived from the similar approach to DNA sequencing. During mass spectrometry, intact proteoforms are typically ionized by electrospray ionization and analysed using a variety of mass analysers, including Orbitraps, Ion Cyclotrons and Time-Of-Flight. Effective fractionation is critical for sample handling before mass-spectrometry-based proteomics. Typical proteome analysis routinely involves digesting intact proteins followed by inferred protein identification using mass spectrometry (MS; Bottom Up proteomics). Top-down proteomics using mass spectrometry interrogates protein structure through measurement of a proteoform's intact mass followed by direct ion dissociation in the gas phase. Top Down proteoform analysis can also be achieved through resolution (separation) of the proteoform from all other proteoforms and then applying peptide-centric LC-MS/MS to characterise the isolated proteoform. A single gene can be coded for many protein products (e.g. via alternative splicing; post-transcriptional and -translational processing) and the resulting canonical amino acid sequences (i.e. 'proteins' or more correctly Open Reading Frame (ORF) products) can be further modified by any number of post-translational modifications (PTM) or non-physiological adducts. These varied protein species or proteoforms define proteomes and are the functional entities underlying biological processes.
=== Environmental and mechanical degradation of plastic === Indoor air, especially in carpeted buildings, contains high concentrations of degraded synthetic fibers, meaning potential exposure to office workers and custodial staff. Settled dust is ingested by adults and particularly children. In wastewater management, recycling facilities, and landfills, plastic goods undergo environmental (weathering) and mechanical degradation. Recycling facilities and landfills serve as reservoirs of particulates workers may potentially be exposed to.
Birch bark tar was more frequently discovered in archaeological contexts dating from the Neolithic to the Iron Age. For example, birch bark tar was identified to serve as an adhesive to repair and decorate/paint ceramic vessels, as a sealing/waterproofing agent. A well-known example of birch bark tar hafting during the copper age is Ötzi’s hafted arrow points and copper axe. Multiple discoveries show that birch bark tar was also used to assemble metal artefacts, such as pendants and other ornaments, on both a functional and decorative level. During the Roman Era, birch bark tar is mostly replaced by wood tar, but birch bark tar is still used, for example, to decorate hinges and other bone objects.
Sources: en.wikipedia.org
Liquid chromatography-tandem mass spectrometry is a common approach. It can detect the parent compound and its metabolites in biological matrices.
Research samples are typically kept frozen, desiccated, and protected from light. Stock solutions are often aliquoted to reduce freeze-thaw cycles.
High-performance liquid chromatography and nuclear magnetic resonance are standard for purity and identity. Mass spectrometry confirms molecular weight.
It is a synthetic REV-ERB agonist used mainly in preclinical research. It is not an approved medicine for human use.