freeze-thaw raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-11-05. Anything still debated is marked as such rather than presented as settled.
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.
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.
Analytical identification and purity assessment often use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Liquid chromatography–tandem mass spectrometry is used to detect and quantify SR9009 in biological matrices, including urine and blood, for anti-doping or pharmacokinetic studies. Nuclear magnetic resonance spectroscopy can confirm molecular structure. Stability depends on form and storage: the solid is generally more stable than solutions, and repeated freeze–thaw cycles may degrade samples. Purity is typically reported as a percentage from a certificate of analysis.
Regulatory treatment of SR9009 varies by country and context. It is not approved as a therapeutic drug by agencies such as the United States Food and Drug Administration or the European Medicines Agency. Sports authorities list it as a prohibited substance; the World Anti-Doping Agency classifies it among hormone and metabolic modulators. Legal status for personal possession or sale differs across jurisdictions, and some countries may restrict it under analog or research chemical laws. Buyers who seek verified material often rely on independent laboratory testing because online product labels may not match contents.
| Property | Value | Notes |
|---|---|---|
| Common name | SR9009 | Also marketed informally as Stenabolic |
| Chemical class | Synthetic REV-ERB agonist | Binds REV-ERBα and REV-ERBβ |
| Molecular formula | C24H30ClN3O4S | Approximate molecular weight 492 g/mol |
| CAS Registry Number | 1379686-30-2 | Identifier for the parent compound |
| Regulatory status | Not approved for human use | Prohibited in sport by WADA |
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.
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 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.
Because REV-ERB receptors are core clock components, SR9009 has been examined for effects on daily rhythms as well as metabolism. Research has explored whether the compound can shift or reinforce circadian gene expression in tissues such as liver and muscle. Some studies report improved metabolic markers in obese or diabetic mice, while others show context-dependent responses. Questions remain about which effects are direct, which are secondary to timing, and how they might differ across species.
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.
Flip–flop kinetics, or flip–flop pharmacokinetics, describes an atypical situation in pharmacokinetics where a drug's rate of absorption or the rate at which it enters the bloodstream is slower than its elimination rate. That is, when the ka (absorption constant) is slower than ke (elimination constant). These circumstances can occur with sustained-release formulations, depot injections, and some subcutaneous or intradermal injections. In the resulting slope of log plasma concentration (log Cp) versus time, the apparent ke is determined by the ka, and the apparent ke is smaller than when the drug is administered intravenously or by immediate-release formulation. Depot injections such as depot antipsychotics and long-acting injectable steroid hormone medications like estradiol valerate, testosterone enanthate, and medroxyprogesterone acetate are examples of drugs with flip–flop kinetics. The term "flip–flop" indicates that the downward slope more closely represents ka rather than ke. Flip–flop kinetics can create difficulties in the determination and interpretation of pharmacokinetic parameters if not recognized.
== Sustainability == Hetero reports its ESG performance annually with reference to the Global Reporting Initiative (GRI), the Sustainability Accounting Standards Board( SASB), and the UN Global Compact. Environment Hetero leads its environment strategy with the stated goal of reaching net zero emissions by 2045. Interim environmental targets include 25% reduction in Scope 1 and Scope 2 emissions by 2030 (with 2022 as a baseline), a 30% increase in the use of renewable energy by 2030, and becoming a Zero Waste to Landfill company in the same year. According to the company’s FY2024-2025 Sustainability report, the company’s Scope 1 emissions were 3,12,435 tCO₂e and Scope 2 emissions were 2,95,020 tCO₂e, resulting in total Scope 1 and Scope 2 emissions of 6,07,455 tCO₂e. Emissions intensity for the year stood at 3.09 tCO₂e per million INR revenue, while biogenic emissions amounted to 72425 tCO₂e. The company also completed its first Scope 3 inventory, covering 13 categories and totalling 1,253,550 tCO₂e. 20% of Hetero’s total energy consumption came from renewable sources. The company recycled 343849 kilolitres of wastewater through Zero Liquid Discharge systems, and recycled 100% of non-hazardous waste, resulting in two sites (Annora and Jeedimetla) receiving Zero Waste to Landfill certification. Social Hetero’s social approach revolves around workforce wellbeing, diversity, inclusion, and occupational safety. As of FY2024-25, Hetero employed 18292 people directly and 10355 people through contract. Women made up 13.63% of direct workforce and 19.28% of contract workers.
== Inhibitors == There are several well-known drugs and toxins that inhibit oxidative phosphorylation. Although any one of these toxins inhibits only one enzyme in the electron transport chain, inhibition of any step in this process will halt the rest of the process. For example, if oligomycin inhibits ATP synthase, protons cannot pass back into the mitochondrion. As a result, the proton pumps are unable to operate, as the gradient becomes too strong for them to overcome. NADH is then no longer oxidized and the citric acid cycle ceases to operate because the concentration of NAD+ falls below the concentration that these enzymes can use. Many site-specific inhibitors of the electron transport chain have contributed to the present knowledge of mitochondrial respiration. Synthesis of ATP is also dependent on the electron transport chain, so all site-specific inhibitors also inhibit ATP formation. The fish poison rotenone, the barbiturate drug amytal, and the antibiotic piericidin A inhibit NADH and coenzyme Q. Carbon monoxide, cyanide, hydrogen sulfide and azide effectively inhibit cytochrome oxidase. Carbon monoxide reacts with the reduced form of the cytochrome while cyanide and azide react with the oxidised form. An antibiotic, antimycin A, and British anti-Lewisite, an antidote used against chemical weapons, are the two important inhibitors of the site between cytochrome B and C1.
==== Neurocognitive consequences ==== Similarly to children, OSA affects cognitive functions in adults. Meta-analysis have shown that the most common cognitive impairments happen in the domains of attention, verbal and visual delayed long-term memory, visuospatial/constructional abilities and executive functions, such as mental flexibility. The executive functioning – mainly dominated by the prefrontal cortex – being significantly impaired in patients with OSA, it is believed that the prefrontal region and its connectivity are affected by sleep disorders. Regarding memory deficits, verbal memory is significantly impaired as patients struggle with immediate and delayed verbal information recall. While meta-analyses have shown no deficits in information retention for patients with OSA, those impairments in verbal memory may be linked to problems in encoding information. This deficit in encoding of information is also noticed in visuo-spatial memory; however, the visual memory seems to be intact in OSA patients. The cognitive impairments have been suggested to result from sleep fragmentation and sleep deprivation, as well as the excessive daytime sleepiness associated with them. More precisely, attention and memory deficits seem to result from sleep fragmentation, while deficits in global cognitive function (executive function, psychomotor function, language abilities) are more related to hypoxia or hypercarbia, which accompanies the obstructive events during sleep.
Sources: en.wikipedia.org
The Geneva College of Longevity Science (GCLS) is a higher-education institution based in Geneva, Switzerland, focused on postgraduate education, professional training and academic work in longevity science and longevity medicine. Established in 2024, the institution provides programmes concerning ageing biology, preventive medicine, healthy ageing and the translation of geroscience into clinical and professional practice. GCLS offers postgraduate and continuing-education programmes in longevity science and related fields. Its activities also include research and framework development concerning physician education and clinical standards in longevity medicine, as well as academic partnerships and scientific meetings.
hypotonic Describing a solution containing a low concentration of dissolved solutes relative to another solution, i.e. having negative osmotic pressure, such that solvent will tend to move by osmosis across a semipermeable membrane from the solution of lower solute concentration to the solution of higher concentration until both solutions have equal concentrations. In a cell where the intracellular cytosol is hypotonic relative to the surrounding extracellular fluid (which by definition is hypertonic relative to the cytosol), the solvent (water) will flow across the plasma membrane out of the cytosol, causing the cell to lose water until both sides of the membrane are isotonic. Cells placed in severely hypertonic environments may be at risk of shriveling and desiccating due to the sudden outflow.
== Background == Degeneracy of the genetic code was identified by Lagerkvist. For instance, codons GAA and GAG both specify glutamic acid and exhibit redundancy; but, neither specifies any other amino acid and thus are not ambiguous or demonstrate no ambiguity. The codons encoding one amino acid may differ in any of their three positions; however, more often than not, this difference is in the second or third position. For instance, the amino acid glutamic acid is specified by GAA and GAG codons (difference in the third position); the amino acid leucine is specified by UUA, UUG, CUU, CUC, CUA, CUG codons (difference in the first or third position); and the amino acid serine is specified by UCA, UCG, UCC, UCU, AGU, AGC (difference in the first, second, or third position). Degeneracy results because there are more codons than encodable amino acids. For example, if there were two bases per codon, then only 16 amino acids could be coded for (4²=16). Because at least 21 codes are required (20 amino acids plus stop) and the next largest number of bases is three, then 4³ gives 64 possible codons, meaning that some degeneracy must exist.
Sources: en.wikipedia.org
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.
No. SR9009 has not been approved as a therapeutic drug in the United States, European Union, or other major markets. Human safety and efficacy data are very limited. Its presence in consumer products does not imply regulatory approval.
The World Anti-Doping Agency lists SR9009 as a prohibited substance because it can alter gene expression and metabolic pathways relevant to performance. The ban applies at all times, not only during competition. Detection relies on laboratory methods such as mass spectrometry.
Legality depends on the country and the intended use. In many places it is sold as a research chemical, but sports and medicine regulations restrict it.