circadian rhythm raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-12-01. Anything still debated is marked as such rather than presented as settled.
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.
At the molecular level, SR9009 binds REV-ERBα and REV-ERBβ and alters their repressive activity on target genes. These nuclear receptors help regulate the circadian clock, lipid synthesis, glucose metabolism, and inflammatory pathways. By changing transcription, the compound can shift the timing or magnitude of downstream metabolic processes in model systems. It does not act through androgen receptors or adenosine receptors, which distinguishes it from several substances sold for athletic performance. Whether the same transcriptional changes occur in humans at tolerable exposures remains an open question because controlled human studies are lacking.
Preclinical reports describe effects on exercise endurance, mitochondrial content, and lipid profiles in rodents, but these findings come from specific experimental conditions. Many studies use high doses or delivery methods that may not translate directly to human use. SR9009 has been reported to have low oral bioavailability and a short half-life, which complicates interpretation of oral dosing studies. It is not established as safe or effective for any indication. Literature discussions often separate its pharmacological mechanism from unverified claims made in fitness and supplement markets.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic REV-ERB agonist | Small-molecule nuclear receptor ligand |
| Appearance | Off-white to pale yellow solid | Typical for research-grade powder |
| Solubility class | Soluble in DMSO; low water solubility | Common stock solutions use organic solvent |
| Typical stock solvent | Dimethyl sulfoxide | Used for laboratory assays |
| Common analytical method | HPLC with UV or mass detection | Used for identity and purity checks |
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.
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 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.
SR9009 is frequently discussed in fitness and research-chemical contexts, yet it has no approved medical indication. Regulatory agencies have not authorized it for human use, and it is not a standard prescription drug. Some sports organizations list it as a prohibited substance because of its potential performance-enhancing properties. Published human data are sparse, so claims about its effects in people often rely on animal models or anecdotal reports. Quality and identity of online materials can vary widely.
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.
The mechanism of action involves binding to REV-ERB receptors and recruiting corepressor complexes, which represses target gene transcription. This contrasts with many nuclear receptor agonists that activate transcription. Downstream effects may include changes in autophagy, mitochondrial biogenesis, and lipid handling, but the precise pathways remain an active area of study. Whether these molecular events translate into meaningful physiological effects in humans is unresolved. Most evidence comes from cultured cells and rodent models rather than human participants.
Claire fixes up his wound and a bond develops between the two; she allows McCormick to stay, and he and Nat later build a simulated bomber-plane cockpit in Nat's treehouse so that McCormick can teach Nat how to fly. McCormick passes out and is hospitalized, where he discovers his body is failing as his age begins to catch up to him. McCormick tracks down Finley's daughter Susan, who informs him her father died in a lab fire before she was born. The FBI discovers there was a warehouse lab fire in the early 40s, and all the scientists including Finley died trying to save the frozen McCormick from the chaos. In the aftermath of the fire, people mistook the cryonics chamber for a water heater, not knowing that McCormick was inside, resulting in him being accidentally frozen for 53 years. She gives McCormick her father's journals, detailing the cryogenic process, and Finley's notes disclose that the rapid aging is irreversible. Susan also reveals that Helen is still alive, but they escape before the FBI, who is now after McCormick, catch up to them. Claire drives McCormick to an air show where he commandeers a B-25 bomber to fly to Helen's seaside-lighthouse home, with Nat stowing away on board. Claire gives Harry's journals to the FBI, for their plans to replicate and modernize the experiment. McCormick suffers another aging attack, forcing Nat (who is now slightly familiar with the plane's controls after his simulated-training session with McCormick) to land the plane in the field near Helen's house.
According to the manufacturer's website, the insulin's action profile in cats was similar to that of NPH insulin, and it lowered blood sugar quickly, but for only about 6–8 hours. Vetsulin was recalled in the US in November 2009 due to inconsistent strength; it was available again as of April 2013. Two ultra-slow time-release synthetic human insulins became available in 2004 and 2005, generically known as insulin detemir (Levemir) and insulin glargine (Lantus). Studies have had good results with insulin glargine in cats. Follow-up research shows that Levemir can be used with a similar protocol and that either insulin on this protocol can lead uncomplicated feline cases to remission, with the most success being in cats who start on these protocols as soon as possible after diagnosis.
Prokineticin is a secreted protein that potently contracts gastrointestinal smooth muscle. Recently, prokineticins have been recognized in humans and other vertebrates. They are thought to be involved in several important physiological processes like neurogenesis, tissue development, angiogenesis, and nociception. Other important physiological roles the Bv8/Prokineticins (PKs) are involved in may include cancer, reproduction, and regulating physiological functions that influence circadian rhythms like hormone secretion, ingestive behaviors, and the sleep/wake cycle. Mutations in the PROK2 (also known as KAL4) gene have been implicated in hypogonadotropic hypogonadism and gynecomastia. An analysis of DNA from Adolf Hitler found he had a deletion in the PROK2 gene, suggesting he may have had Kallman syndrome.
===== Efficacy ===== After its launch in 2015 and marketed as Addyi, the drug experienced controversies and rejection from being acknowledged after three reviews on the clinical trials. Regarding the eligible prescription criteria concluded from the trials, the patient should have a diagnosed psychological pathology, medical comorbidities, and the presence of personal relationship issues. Despite being the first drug, its efficacy was not significant for treatment less than at least four weeks. Treatment withdrawal is also practiced if recipients do not experience improvements in symptoms after eight weeks. Nevertheless, around 18% of the gain was observed after 24 weeks of treatment.
Sources: en.wikipedia.org
In materials science and molecular biology, thermostability is the ability of a substance to resist irreversible change in its chemical or physical structure, often by resisting decomposition or polymerization, at a high relative temperature. Thermostable materials may be used industrially as fire retardants. A thermostable plastic, an uncommon and unconventional term, is likely to refer to a thermosetting plastic that cannot be reshaped when heated, than to a thermoplastic that can be remelted and recast. Thermostability is also a property of some proteins. To be a thermostable protein means to be resistant to changes in protein structure due to applied heat.
Tolerance to psilocybin appears after a single dose and dissipates dissipates after a few days. A cross-tolerance can develop between psilocybin and other classical psychedelics such as LSD, mescaline and DOM. Repeated use of psilocybin does not lead to physical dependence or drug withdrawal. Despite the rapid onset of tolerance, rates of self-administration in Rhesus macaques are low, which usually indicates a low abuse potential. A 2008 study concluded that, based on U.S. data from 2000 to 2002, adolescent-onset usage of hallucinogenic drugsdid not increase the risk of drug dependence in adulthood; this was in contrast to adolescent usage of cannabis, cocaine, inhalants, anxiolytic medicines, and stimulants, all of which were associated with "an excess risk of developing clinical features associated with drug dependence". Multiple studies in 2010 ranked the relative harm of psilocybin mushrooms below all other drugs in a selection of 19 recreational drugs, including alcohol, cannabis, cocaine, ecstasy, heroin, and tobacco.
=== Emulsification === Due to the hydrophilic property of sucrose and the lipophilic property of fatty acids, the overall hydrophilicity of sucrose esters can be tuned by the number of hydroxyl groups that are reacted with fatty acids and the identity of the fatty acids. The fewer free hydroxyl groups and the more lipophilic fatty acids, the less hydrophilic the resulting sucrose ester becomes. Sucrose esters' HLB values can range from 1-16. Low HLB (3.5-6.0) sucrose esters act as a water-in-oil emulsifier while high HLB (8-18) sucrose esters act as an oil-in-water emulsifier.
Sources: en.wikipedia.org
The main effect of glaucoma is damage to the optic nerve. Eventually, this damage leads to vision loss, which can deteriorate with time. The underlying cause of open-angle glaucoma remains unclear. Several theories exist on its exact etiology. Intraocular pressure is a function of the production of liquid aqueous humor by the ciliary processes of the eye, and its drainage through the trabecular meshwork. Aqueous humor flows from the ciliary processes into the posterior chamber, bounded posteriorly by the lens and the zonules of Zinn, and anteriorly by the iris. It then flows through the pupil of the iris into the anterior chamber, bounded posteriorly by the iris and anteriorly by the cornea. From here, the trabecular meshwork drains aqueous humor via the scleral venous sinus (Schlemm's canal) into scleral plexuses and general blood circulation. In open/wide-angle glaucoma, flow is reduced through the trabecular meshwork due to the degeneration and obstruction of the trabecular meshwork, whose original function is to absorb the aqueous humor. Loss of aqueous humor absorption leads to increased resistance and thus a chronic, painless buildup of pressure in the eye. In primary angle-closure glaucoma, the iridocorneal angle is narrowed or completely closed, obstructing the flow of aqueous humor to the trabecular meshwork for drainage. This is usually due to the forward displacement of the iris against the cornea, resulting in angle closure. This accumulation of aqueous humor causes an acute increase in pressure and damage to the optic nerve.
==== Comparison of pharmacokinetics between dosage forms ==== The free acid (HMB-FA) and monohydrated calcium salt (HMB-Ca) forms of HMB have different pharmacokinetics. HMB-FA is more readily absorbed into the bloodstream and has a longer elimination half-life (3 hours) relative to HMB-Ca (2.5 hours). Tissue uptake and utilization of HMB-FA is 25–40% higher than for HMB-Ca. The fraction of an ingested dose that is excreted in urine does not differ between the two forms.
== Side effects == Neumega has caused allergic reaction which at times have been very serious. Symptoms have been edema of the face and tongue, or larynx; shortness of breath; wheezing; chest pain; hypotension (including shock); dysarthria; loss of consciousness, rash, urticaria, flushing, and fever. These reaction can occur after the first dose or after any later application. Neumega should be permanently discontinued in patients with any sign of allergy. Treatment is largely symptomatic. Oprelvekin also has caused quite often fluid retention, ranging from peripheral edema (approximately 40% of patients) to dyspnea and full developed lung edema with or without cardiac decompensation (see contraindications and precautions). These symptoms have led to some deaths. Fluid retention may also lead to dilutional anemia (in 10 to 15% of patients). Hypokalemia may also result. Symptoms of fluid retention have been observed more often in patients following myeloablative chemotherapy (see contraindications). Severe arrhythmias (atrial flutter and atrial fibrillation) as well as fatal cardiac arrest have also been seen which may or may be not attributed to fluid retention/increased volume. Isolated cases of stroke have been noted, those patients with previous transient ischemic attacks or partial/minor strokes may be at particular risk. Papilledema of the eyes has been observed (2%) and may lead to disturbed visual acuity and even temporary or permanent blindness. Patients with preexisting papilledema or with involvement of the central nervous system may be at higher risk.
Sources: en.wikipedia.org
SR9009 is a synthetic research compound that acts on REV-ERB nuclear receptors. It is not approved for human use and is sold only as a research chemical. Its effects have been studied mainly in cells and rodents.
It binds REV-ERB alpha and REV-ERB beta and changes the expression of genes tied to metabolism and circadian rhythm. These changes can affect mitochondria and energy use in animal models. The exact chain from receptor binding to physiological outcome is still being mapped.
No reliable human trials show that SR9009 improves athletic performance. Some rodent studies report endurance changes, but these results are not proof of human benefit. Its use in sport is prohibited, and quality and safety data are lacking.
SR9009 is a synthetic REV-ERB agonist used in laboratory research. It is not an approved drug, and its effects in humans are not well characterized. It is often sold as a research chemical under the name Stenabolic.