The short version of freeze-thaw fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-05-18. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C20H24ClN3O4S | Reported for the free base |
| Molecular weight | 437.9 g/mol | Calculated from the formula |
| Primary target | REV-ERBα and REV-ERBβ | Nuclear receptors involved in circadian regulation |
| Solubility | Soluble in DMSO and ethanol | Poorly soluble in water |
| Typical storage | -20 °C, desiccated | Protect from light and moisture |
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.
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.
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.
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.
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.
During the 1950s and 1960s, CSL produced semisynthetic penicillin as well. Penicillin was also produced by F.H. Faulding in South Australia, Abbott Laboratories in New South Wales and Glaxo in Victoria. By the 1970s there was a worldwide glut of penicillin. Glaxo ceased production in 1975 followed by CSL in 1980.
In 2012, Kahala signed a franchising deal with Phoenix-based America's Taco Shop. In 2013, a controlling interest in Kahala Corp. was purchased by the Serruya family of Canada. The Serruyas own and founded Yogen Früz, a chain with 1400 stores around the world. At that time, Michael Serruya became Chairman and Co-CEO of Kahala Corp. Shortly thereafter, Co-CEO Kevin Blackwell left the company. The Serruya family changed the company name from Kahala Corp to Kahala Brands to better align the focus of the business. In June 2015, Kahala Brands purchased Planet Smoothie and Tasti D-Lite. This acquisition added 128 new locations to the overall company store count and increased the total of smoothie-focused locations to over 400 worldwide. Just a few months later in November 2015, Kahala Brands purchased the gourmet coffee and smoothie brand Maui Wowi. At the time of the acquisition, Maui Wowi had with 400 mobile carts and 29 standalone retail units that operated by 200 franchisees. The following month, Kahala acquired Pinkberry in December. In July 2016, MTY Food Group Inc. of Montreal, Quebec in Canada purchased Kahala Brands for approximately US$310 million. Under the deal, Kahala remained in its headquarters in Scottsdale, Arizona while MTY's US operations was moved into Kahala's offices. Kahala's Chief Operating Officer Jeff Smit was chosen to lead the US operations of the combined entity.
The AZFc subregion is located in the distal part of Yq11. Genes in this region have a diverse role, but overall, they are essential to complete spermatogenesis. AZFc deletions have been associated with drastic reduction in sperm count, and there are subsets of men with AZFc microdeletions that experience progressive declines in their sperm count. There are multiple candidate genes in the AZFc region that have been shown to cause infertility in males: Deleted in Azoospermia (DAZ), Chromodomain Protein, Y-linked (CDY), and Basic Protein, Y-linked, 2 (BPY2). AZFc is one of the most genetically dynamic regions in the human genome, possibly serving as counter against the genetic degeneracy associated with the lack of a partner chromosome during meiosis. However, such strategy comes has the adverse effects that some rearrangements represent a risk factor or a de facto causative agent of spermatogenic disruption. A specific partial deletion of AZFc called gr/gr deletion is significantly associated with male infertility among Caucasians in Europe and the Western Pacific region.
HGPS is caused by mutations that weaken the structure of the cell nucleus, making normal cell division difficult. The histone mark H4K20me3 is involved and caused by de novo mutations that occur in a gene that encodes lamin A. Lamin A is made but is not processed properly. This poor processing creates an abnormal nuclear morphology and disorganized heterochromatin. Patients also do not have appropriate DNA repair, and they also have increased genomic instability. In normal conditions, the LMNA gene codes for a structural protein called prelamin A, which undergoes a series of processing steps before attaining its final form, called lamin A. Prelamin A contains a "CAAX" where C is a cysteine, A an aliphatic amino acid, and X any amino acid. This motif at the carboxyl-termini of proteins triggers three sequential enzymatic modifications. First, protein farnesyltransferase catalyzes the addition of a farnesyl moiety to the cysteine. Second, an endoprotease that recognizes the farnesylated protein catalyzes the peptide bond's cleavage between the cysteine and -aaX. In the third step, isoprenylcysteine carboxyl methyltransferase catalyzes methylation of the carboxyl-terminal farnesyl cysteine. The farnesylated and methylated protein is transported through a nuclear pore to the interior of the nucleus. Once in the nucleus, the protein is cleaved by a protease called zinc metallopeptidase STE24 (ZMPSTE24), which removes the last 15 amino acids, which includes the farnesylated cysteine. After cleavage by the protease, prelamin A is referred to as lamin A.
== Career == Working first in the Physical Chemistry Laboratory, he moved to the Dunn Nutritional Laboratory, and in 1938 moved to Wool Industries Research Institution in Leeds. He was head of the biochemistry division of Boots Pure Drug Company from 1946 to 1948, when he joined the Medical Research Council. There, he was appointed head of the physical chemistry division of the National Institute for Medical Research in 1952, and was chemical consultant from 1956 to 1959. He specialised in biochemistry, in some aspects of vitamins E and B2, and in techniques that laid the foundation for several new types of chromatography. He developed partition chromatography whilst working on the separation of amino acids, and later developed gas-liquid chromatography with Anthony T. James. Amongst many honours, he received his Nobel Prize in 1952. After his retirement from the University of Sussex, he was visiting professor at both the University of Houston in Texas and the EPFL (École Polytechnique Fédérale de Lausanne) in Switzerland. He published far fewer papers than the typical Nobel winners—only 70 in all—but his ninth paper contained the work that would eventually win him the Nobel Prize. The University of Houston dropped him from its chemistry faculty in 1979 (when he was 69 years old) because he was not publishing enough.
Sources: en.wikipedia.org
Migraine was first comprehensively classified in 1988, when the International Headache Society (IHS) began its classification of headache disorders. The IHS updated its classification of headaches in 2004, and a third version was published in 2018. According to this classification, migraine is a primary headache disorder along with tension headaches and cluster headaches. The classification of migraine includes six broad categories:
=== Addition of translation-independent amino acids === Presence of a ribosome quality control protein Rqc2 is associated with mRNA-independent protein elongation. This elongation is a result of ribosomal addition (via tRNAs brought by Rqc2) of CAT tails: ribosomes extend the C-terminus of a stalled protein with random, translation-independent sequences of alanines and threonines.
=== Conflict with the US and its allies: 1981–1986 === The early 80s saw economic trouble in Libya; from 1982 to 1986, annual oil revenues dropped from $21 to $5.4 billion. Focusing on irrigation projects, 1983 saw construction start on Libya's largest and most expensive infrastructure project, the Great Man-Made River; although designed to be finished by the end of the decade, it remained incomplete at the start of the 21st century. Military spending increased, while other administrative budgets were cut. Foreign debt rose, and austerity measures were introduced to promote self-reliance; in 1985 there was a mass deportation of foreign workers, mostly Egyptian and Tunisian. Domestic threats continued to plague Gaddafi; in May 1984, his Bab al-Azizia home was unsuccessfully attacked by a militia—linked to the NFSL or Muslim Brotherhood—and in the aftermath 5,000 dissidents were arrested. In spring 1985, members of the military tried to assassinate Gaddafi twice. The first was a plot by conservative officers to assassinate him at a villa on the outskirts of Tripoli; the second was an assault on his convoy. In November 1985, Colonel Hassan Ishkal, the third most powerful man in Libya, head of the military region of Sirte, died in a suspicious car accident. Ishkal's death was attributed to Jalloud, Khalifa Hunaysh or Gaddafi.
== Political career == On March 17, 2017, Ayyadurai filed as a Republican candidate in the 2018 United States Senate election in Massachusetts, running against incumbent Elizabeth Warren. He ran as an independent and placed third with 3.4% of the votes. Ayyadurai said that Senator Warren was at the top of a U.S. "neo–caste system" composed of "academics, career politicians and lawyer/lobbyists", a "spineless clan" who never expect to be challenged. He said he would take a science and engineering perspective on problem solving, focusing on immigration, education and innovation. He called for secure borders and an end to sanctuary cities, support for more choices in public education, and for more scrutiny of "pay-to-play" science research. Ayyadurai has accused Warren of voting in favor of the Farmer Assurance Provision and against a GM labeling bill sponsored by Senator Bernie Sanders of Vermont. However, the Act was reportedly passed to avoid a government shutdown, and Warren petitioned the Food and Drug Administration for "regulations to ensure that the labeling of GMO products is fair, standardized and transparent". In August 2017, Ayyadurai spoke at the Boston Free Speech rally, a gathering whose speaker line-up included right-wing extremists, and which drew large counter-protests. Ayyadurai later disputed how the event was characterized, tweeting that the "establishment" wanted to block attendance and media coverage and sought a "Race War to divide us".
∗Fifteen puffs were chosen to estimate the nicotine delivery of one traditional cigarette. Each e-cigarette cartridge, which varies across manufacturers, and each cartridge produces 10 to 250 puffs of vapor. This correlates to 5 to 30 traditional cigarettes. A puff usually lasts for 3 to 4 seconds. A 2014 study found there is wide differences in daily puffs in experienced vapers, which typically varies from 120 to 225 puffs per day. From puff-to-puff e-cigarettes do not provide as much nicotine as traditional cigarettes. A 2016 review found "The nicotine contained in the aerosol from 13 puffs of an e-cigarette in which the nicotine concentration of the liquid is 18 mg per milliliter has been estimated to be similar to the amount in the smoke of a typical tobacco cigarette, which contains approximately 0.5 mg of nicotine."
Sources: en.wikipedia.org
== Biological function == G-CSF is produced by endothelium, macrophages, and a number of other immune cells. The natural human glycoprotein exists in two forms, a 174- and 177-amino-acid-long protein of molecular weight 19,600 grams per mole. The more-abundant and more-active 174-amino acid form has been used in the development of pharmaceutical products by recombinant DNA (rDNA) technology.
=== Suppression of the pro-Alid groups === Mu'awiya died in 680 and was succeeded by his son Yazid I. Mu'awiya's designation of his son was an unprecedented act and shocked many in the Muslim community, particularly the Arab nobility of Kufa. They long sympathized with Caliph Ali, Mu'awiya's former rival, and Ali's family. One of Ali's sons, Husayn dispatched his cousin Muslim ibn Aqil to Kufa to set the stage for Husayn's accession to the caliphate. Ibn Aqil garnered significant support and was hosted by a prominent pro-Alid nobleman. Ubayd Allah became aware of Ibn Aqil's activities, prompting the latter to launch a premature assault against the governor. Ubayd Allah was holed up in his palace, but thirty men from his shurta (security forces) fended off Ibn Aqil's partisans, while he persuaded many Kufan noblemen to back him against Ibn Aqil, who was abandoned by his supporters and slain on 10 September 680. Husayn had already been en route to Kufa from Medina when he received news of Ibn Aqil's execution. Ubayd Allah was prepared for Husayn's arrival and sent troops to intercept him. They prevented Husayn and his small retinue from reaching the watered areas of the province. The two sides negotiated for weeks, but Ubayd Allah refused Husayn entry into Kufa or return to Arabia while Husayn refused to recognize Yazid's caliphate. In the end, a short battle was fought at Karbala on 10 October 680, in which Husayn and nearly all of his partisans were slain.
Some of the functions of tears include lubricating the eyes (basal tears), removing irritants (reflex tears), and also aiding the immune system. Tears also occur as a part of the body's natural pain response. Emotional secretion of tears may serve a biological function by excreting stress-inducing hormones built up through times of emotional distress. Tears have symbolic significance among humans.
== Chemistry == While the molecular weight of nicotinamide riboside is 255.25 g/mol, that of its chloride salt is 290.70 g/mol. As such, 100 mg of nicotinamide riboside chloride provides 88 mg of nicotinamide riboside.
Philip E. Dawson is a scientist and academic leader, known for his contributions to the field of chemistry, particularly in synthetic protein chemistry and peptide science. He currently serves as the Dean of Graduate and Postdoctoral Studies at Scripps Research, where he is also a professor in the Department of Chemistry.
Sources: en.wikipedia.org
It is a synthetic REV-ERB agonist used mainly in preclinical research. It is not an approved medicine for human use.
It binds to REV-ERBα and REV-ERBβ, nuclear receptors involved in circadian and metabolic gene regulation. This can alter transcription of genes related to lipid and glucose metabolism in experimental models.
No controlled human trials have established that effect. Endurance findings come primarily from rodent studies, and human responses remain unknown.
SR9009 is a synthetic research compound that binds and modulates the nuclear receptors REV-ERBα and REV-ERBβ. It is used in laboratory studies of circadian biology and metabolism, not as an approved medicine. It is also known by the informal name Stenabolic.