A practical reference on NR1D2: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-07-31. Anything still debated is marked as such rather than presented as settled.
SR9009 is a synthetic small molecule developed as an agonist of the nuclear receptors REV-ERBα (NR1D1) and REV-ERBβ (NR1D2). These receptors help regulate circadian rhythms and metabolic gene expression. In cell and animal studies, SR9009 alters transcription of genes involved in lipid metabolism, inflammation, and mitochondrial function. It is not an approved medicine, and its pharmacological profile in humans remains largely uncharacterized. The compound is frequently discussed in the context of circadian biology and metabolic research rather than clinical use.
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.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ, also called NR1D1 and NR1D2. These receptors help regulate circadian rhythms and metabolic gene programs. The compound was developed for laboratory research, not as an approved therapeutic. Its identity is distinct from steroid hormones and selective androgen receptor modulators. Scientific interest centers on how REV-ERB activation changes gene expression in cells and animal models.
At the molecular level, SR9009 binds the ligand-binding domain of REV-ERB and strengthens recruitment of corepressor proteins such as NCoR and HDAC3. This increases repression of target genes, including Bmal1 and other clock-controlled and metabolic genes. In rodent studies, such changes have been linked to altered lipid handling, glucose metabolism, and energy expenditure. The precise chain of events between receptor binding and whole-body effects remains an active area of research. Findings in animals do not automatically translate to humans.
Laboratory studies often administer SR9009 by injection because oral absorption appears poor in rodents. Reported pharmacokinetic properties include rapid metabolism and low systemic exposure after oral dosing. Human pharmacokinetic data are sparse, so absorption, distribution, metabolism, and excretion in people are not well defined. Some research explores related REV-ERB compounds with improved drug-like properties. Regulatory approval for any REV-ERB agonist as a human medicine has not been granted to date.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic REV-ERB agonist | Small molecule; not a steroid or peptide. |
| Primary targets | NR1D1 and NR1D2 | Also known as REV-ERBα and REV-ERBβ. |
| Studied routes | Intraperitoneal in rodents | Oral bioavailability in humans is not established. |
| Human approval | No approved therapeutic indication | No recognized clinical use. |
| Key uncertainty | Human physiological effects | Preclinical findings may not translate. |
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is not an approved medicine and has no established human therapeutic use. The compound appears in scientific literature as a tool for probing circadian and metabolic regulation. Online sellers often label it as a research chemical, sometimes using the nickname Stenabolic. Its chemical identity is distinct from selective androgen receptor modulators, stimulants, and peroxisome proliferator-activated receptor delta agonists. Researchers use it mainly in cell and animal experiments.
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.
Laboratory samples of SR9009 are typically handled as research chemicals rather than pharmaceuticals. Suppliers usually state that the material is for research use only and not for human or veterinary administration. Storage recommendations generally call for a freezer at approximately −20 °C, protection from light, and a desiccated environment. The solid is often described as a white to off-white powder. Solubility is commonly reported in organic solvents such as dimethyl sulfoxide and ethanol, with low solubility in water.
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.
For some non-coding RNA, the mature RNA is the final gene product. In the case of messenger RNA (mRNA) the RNA is an information carrier coding for the synthesis of one or more proteins. mRNA carrying a single protein sequence (common in eukaryotes) is monocistronic whilst mRNA carrying multiple protein sequences (common in prokaryotes) is known as polycistronic.
==== Analytical chemistry ==== Often there are chemical species present or necessary at one stage of sample processing that will interfere with the analysis. For example, some air monitoring is performed by drawing air through a small glass tube filled with sorbent particles that have been coated with a chemical to stabilize or derivatize the analyte of interest. The coating may be of such a concentration or characteristics that it would damage the instrumentation or interfere with the analysis. If the sample can be extracted from the sorbent using a nonpolar solvent (such as toluene or carbon disulfide), and the coating is polar (such as HBr or phosphoric acid) the dissolved coating will partition into the aqueous phase. Clearly the reverse is true as well, using polar extraction solvent and a nonpolar solvent to partition a nonpolar interferent. A small aliquot of the organic phase (or in the latter case, polar phase) can then be injected into the instrument for analysis.
Prolyl endopeptidase is a large cytosolic enzyme that belongs to a distinct class of serine peptidases. It was first described in the cytosol of rabbit brain as an oligopeptidase, which degrades the nonapeptide bradykinin at the Pro-Phe bond. The enzyme is involved in the maturation and degradation of peptide hormones and neuropeptides such as alpha-melanocyte-stimulating hormone, luteinizing hormone-releasing hormone (LH-RH), thyrotropin-releasing hormone, angiotensin, neurotensin, oxytocin, substance P and vasopressin. PREP cleaves peptide bonds at the C-terminal side of proline residues. Its activity is confined to action on oligopeptides of less than 10 kD and it has an absolute requirement for the trans-configuration of the peptide bond preceding proline. Prolyl endopeptidases are involved in the maturation and degradation of peptide hormones and neuropeptides.
Sources: en.wikipedia.org
depression or lethargy confusion or dizziness trembling weakness ataxia (loss of coordination or balance) loss of excretory or bladder control (sudden house accident) vomiting, and then loss of consciousness and possible seizures Successful home treatment of a hypoglycemia event depends on being able to recognize the symptoms early and responding quickly with treatment. Trying to make a seizing or unconscious animal swallow can cause choking on the food or liquid. There is also a chance that the materials could be aspirated (enter the lungs instead of being swallowed). Seizures or loss of consciousness because of low blood glucose levels are medical emergencies.
CIVIL RECORDS Held in the 20 arrondissement town halls: Births from 1925 to the present. Marriages from 1948 to the present. Deaths from 1987 to the present. Available at the Paris Archives: Before 1860: Births, marriages, and deaths from the 16th century to 1859—alphabetical-chronological indexes and records of the so-called “reconstructed” civil status from former parishes of Paris, the 12 former arrondissements, and fully or partially annexed communes in 1860. From 1860 onwards: Decennial tables: Births, marriages, and deaths up to 1932. Marriages from 1955 to 1974. Deaths from 1955 to 1984. Annual tables: Marriages from 1933 to 1954 (only record numbers are listed). Deaths from 1933 to 1954 (only record numbers are listed) and from 1985–1986. Records: Births up to 1922. Marriages up to 1947. Deaths up to 1986. Available on-site at the Paris Archives: Records from the second reconstruction (V.5.E). 29 registers of parish or civil status records from the 18th and 19th centuries not destroyed in 1871 (V.6.E 1–29). Births from 1923 and 1924. CATHOLIC RECORDS Baptisms, marriages, and burials from the 16th century to 1792—about 50 parish registers, mostly containing excerpts, preserved at the National Archives and the National Library. Baptisms, marriages, and burials from all Parisian churches from 1793 to 1909 (with gaps): First copies preserved in parishes (a single register for burials). Second copies (baptisms and marriages only) deposited at the Paris Archives by the Archdiocese.
aeruginosa has also been reported to possess multidrug efflux pumps systems that confer resistance against a number of antibiotic classes, and the MexAB-OprM (Resistance-nodulation-division (RND) family) is considered as the most important. An important factor found to be associated with antibiotic resistance is the decrease in the virulence capabilities of the resistant strain. Such findings have been reported in the case of rifampicin-resistant and colistin-resistant strains, in which decrease in infective ability, quorum sensing, and motility have been documented. Mutations in DNA gyrase are commonly associated with antibiotic resistance in P. aeruginosa. These mutations, when combined with others, confer high resistance without hindering survival. Additionally, genes involved in cyclic-di-GMP signaling may contribute to resistance. When P. aeruginosa is grown under in vitro conditions designed to mimic a cystic fibrosis patient's lungs, these genes mutate repeatedly. Two small RNAs, Sr0161 and ErsA, were shown to interact with mRNA encoding the major porin OprD responsible for the uptake of carbapenem antibiotics into the periplasm. The sRNAs bind to the 5'UTR of oprD, causing increase in bacterial resistance to meropenem. Another sRNA, Sr006, may positively regulate (post-transcriptionally) the expression of PagL, an enzyme responsible for deacylation of lipid A. This reduces the pro-inflammatory property of lipid A. Furthermore, similar to a process found in Salmonella, Sr006 regulation of PagL expression may aid in polymyxin B resistance.
Sources: en.wikipedia.org
It is a synthetic compound that acts as an agonist at REV-ERBα and REV-ERBβ. It is used mainly as a research chemical to study circadian and metabolic pathways. It is not approved for human therapeutic use.
REV-ERB receptors generally repress transcription when bound by natural heme. SR9009 is described as an agonist that enhances this repressive activity. The result is altered expression of clock and metabolic genes.
Published controlled human trials are lacking. Some sources cite limited or unofficial reports, but these do not establish safety or efficacy. Claims about human performance effects remain unverified.
SR9009 is a synthetic research compound that activates the REV-ERBα and REV-ERBβ nuclear receptors. It is not an approved drug and has no established human therapeutic use. Most published biological data come from cell and rodent studies.