A practical reference on Nuclear receptor: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-12-04 and is reviewed periodically as new material appears.
PPARδ is a nuclear receptor that regulates gene expression related to fatty acid oxidation, glucose homeostasis, and mitochondrial function. GW501516 binds to this receptor with high affinity and activates downstream signaling in skeletal muscle and other tissues. Animal studies reported increased endurance and altered fuel preference, but human data remain limited and inconsistent. The precise relationship between receptor activation and observed physiological changes is still an area of active investigation. Researchers have also examined whether the compound affects inflammation or cell proliferation. No approved therapeutic indication exists for cardarine.
In laboratory settings, cardarine is studied as a tool compound for probing PPARδ biology. Published experiments often use cell cultures, rodent models, or isolated tissues. Some investigations focus on metabolic effects, while others assess potential risks such as carcinogenicity observed in long-term animal studies. Because human trials are sparse, most knowledge comes from preclinical work and adverse event reports. Scientific literature frequently notes the gap between animal findings and human outcomes. The compound is not a dietary supplement and is not intended for human consumption.
Cardarine is a common name for GW501516, a synthetic compound developed in the 1990s through research collaborations involving GlaxoSmithKline. It belongs to a class of molecules known as peroxisome proliferator-activated receptor delta agonists. Early studies explored its effects on lipid metabolism and energy expenditure in animal models. The compound was never approved as a human medicine, and clinical development was discontinued. In the years since, it has appeared in fitness and bodybuilding communities as a performance-enhancing substance. Regulatory agencies classify it as an unapproved drug.
GW501516 acts as an agonist at the peroxisome proliferator-activated receptor delta, a nuclear receptor that regulates gene expression. Activation shifts transcription toward genes involved in fatty acid uptake, oxidation, and energy expenditure. The compound does not bind the androgen receptor and therefore differs from anabolic steroids and SARMs. In rodent models, this metabolic shift has been linked to increased running endurance and reduced fat accumulation. The exact downstream pathways in humans remain incompletely characterized.
Early clinical research explored GW501516 for lipid disorders, obesity, and diabetes. Some short-term human studies reported changes in HDL cholesterol, LDL cholesterol, and triglycerides. The development program was discontinued after rodent studies showed dose-dependent tumor formation in multiple tissues, including liver, bladder, stomach, and skin. These findings raised concerns about long-term cancer risk in humans. Because human exposure data are limited, the clinical significance of the rodent tumors remains uncertain.
Literature on cardarine often separates receptor pharmacology from toxicology. Mechanistic papers describe PPARδ activation and gene expression changes, while safety assessments focus on carcinogenicity and species differences. Questions remain about whether rodent tumors arise through PPARδ-dependent or off-target mechanisms. Another open area is how human metabolism and exposure compare with those in animal studies. Analytical methods such as liquid chromatography–mass spectrometry are used to confirm identity in biological and product samples.
| Property | Value | Notes |
|---|---|---|
| CAS Registry Number | 317318-70-0 | Unique identifier for the compound. |
| Chemical class | PPARδ agonist | Synthetic ligand for peroxisome proliferator-activated receptor delta. |
| Appearance | White to off-white solid | Typical form of research-grade material. |
| Solubility | Soluble in DMSO and ethanol | Poorly soluble in water. |
| Typical storage | -20°C | Recommended for long-term storage of stock solutions. |
Cardarine is prohibited in competitive sport under the World Anti-Doping Agency code, where it is classified as a metabolic modulator. It is not approved as a prescription medicine in the United States, European Union, or other major markets. Regulatory action has focused on its presence in sports and in products marketed as research chemicals. Because it has no accepted medical indication, supply is often unregulated. This status creates legal and safety uncertainties for anyone who encounters the substance.
Anti-doping laboratories detect GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be used in some programs. Detection depends on factors such as dose, timing, metabolism, and the sensitivity of the assay. Published methods describe limits of detection in the low nanogram per milliliter range for related compounds. Exact detection windows are not fixed for all situations and remain an area of ongoing study.
Products sold as cardarine have been found to contain incorrect compounds, variable amounts, or no active ingredient at all. Independent testing is required to verify identity and purity. Common analytical approaches include high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance for structural confirmation. These methods can distinguish GW501516 from related PPAR agonists and from unrelated steroids. For regulators and researchers, such verification is central to interpreting both biological results and adverse event reports.
Cardarine can be detected in biological samples and product materials using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method separates compounds by chromatography and identifies them by mass-to-charge transitions, allowing low-level detection in urine or blood. Sample preparation often involves enzymatic hydrolysis, solid-phase extraction, or protein precipitation. Certified reference materials and isotope-labeled internal standards improve quantification. Detection windows depend on metabolism, matrix, and assay sensitivity, so no single universal window applies.
Regulatory treatment of cardarine differs by context and jurisdiction. In competitive sport, the World Anti-Doping Agency lists PPARδ agonists, including GW501516, as prohibited at all times. Outside sport, it lacks approval as a prescription medicine in major drug markets, and products sold for human consumption may be treated as unapproved drugs. Some countries also restrict importation or sale through general consumer protection and medicines laws. These classifications affect availability, testing, and legal risk without establishing therapeutic value.
Cardarine is a common name for GW501516, a synthetic compound first described in the 1990s as a selective agonist of the peroxisome proliferator-activated receptor delta. It was studied in preclinical models for metabolic and cardiovascular conditions, but it has not been approved as a medicine in the United States, Europe, or other major jurisdictions. Retail products labeled as cardarine are generally research chemicals or supplements, not pharmaceutical formulations. Because human safety and efficacy data remain limited, regulatory agencies treat it as an unapproved substance rather than a therapeutic product.
Sporting authorities added GW501516 to prohibited lists after it appeared in athlete samples and online markets. The World Anti-Doping Agency classifies it as a hormone and metabolic modulator, and its use can lead to an anti-doping rule violation. Some early laboratory work suggested effects on fatty acid oxidation and endurance-related metabolism in animals, but those findings do not establish safe or effective use in people. Reports of adverse events in humans are scarce and often anecdotal, which complicates risk assessment.
=== Amateur career === Casey made her amateur debut in 2012, losing a split decision to future UFC Strawweight Emily Kagan. Casey then went on a four fight win streak, earning three wins by armbar and capturing the Tuff-N-Uff Flyweight title in the process and defending it once.
=== Analogues === 4-AcO-DMT is closely related to psilocin (4-HO-DMT) and psilocybin (4-PO-DMT). It is a lower homologue of 4-AcO-MET, 4-AcO-DET, 4-AcO-MiPT, and 4-AcO-DiPT. Other analogues of 4-AcO-DMT include 4-AcO-DPT, 4-MeO-DMT, and 4-PrO-DMT (O-propionylpsilocin). Other related prodrugs of psilocin besides 4-AcO-DMT, 4-PrO-DMT, and psilocybin include CT-4201, EB-002, RE-109 (4-GO-DMT), and MSP-1014.
The caloric content of breastmilk is reflective of the caloric requirements of the infant, increasing steadily after 12 months. The caloric content of breastmilk in the first 12 months of breastfeeding is approximated to be 58-72 Calories/100mL. Comparatively, the caloric content after 48 months is approximately 83-129 Calories/100mL. When a mother has her full milk supply and is feeding her infant, the first milk to be expressed is called the foremilk. Foremilk is typically thinner and less rich in calories. The hindmilk that follows is rich in calories and fat. If the mother is not deficient in vitamins, breast milk normally supplies the baby's needs, except for Vitamin D. The CDC, National Health Service (UK), Canadian Paediatric Society, the American Academy of Pediatrics, and the American Academy of Family Physicians all agree that breast milk alone does not provide infants with an adequate amount of Vitamin D, thus they advise parents to supplement their infants with 400 IU Vitamin D daily. Providing this quantity of Vitamin D to breastfeeding infants has been shown to reduce rates of Vitamin D insufficiency (defined as 25-OH vitamin D < 50 nmol/L). However, there was insufficient evidence in the most recent Cochrane Review to determine if this quantity reduced rates of Vitamin D deficiency (defined as 25-OH vitamin D < 30 nmol/L) or rickets. Term infants typically do not need iron supplementation. Delaying cord clamping at birth for at least one minute improves the infants' iron status for the first year.
Sources: en.wikipedia.org
Formica polyctena, among other ant species, constructs nests that maintain a relatively constant interior temperature that aids in the development of larvae. The ants maintain the nest temperature by choosing the location, nest materials, controlling ventilation and maintaining the heat from solar radiation, worker activity and metabolism, and in some moist nests, microbial activity in the nest materials. Some ant species, such as those that use natural cavities, can be opportunistic and make use of the controlled micro-climate provided inside human dwellings and other artificial structures to house their colonies and nest structures.
== Structural studies == As of late 2007, 34 structures have been solved for this class of enzymes, with PDB accession codes PDB: 1IX1, PDB: 1LM4, PDB: 1LM6, PDB: 1LME, PDB: 1LQW, PDB: 1LQY, PDB: 1LRU, PDB: 1LRY, PDB: 1N5N, PDB: 1Q1Y, PDB: 1S17, PDB: 1SV2, PDB: 1SZZ, PDB: 1V3Y, PDB: 1VEV, PDB: 1VEY, PDB: 1VEZ, PDB: 1WS0, PDB: 1WS1, PDB: 1XEM, PDB: 1XEN, PDB: 1XEO, PDB: 1Y6H, PDB: 1ZXZ, PDB: 1ZY0, PDB: 1ZY1, PDB: 2AI7, PDB: 2AI8, PDB: 2AI9, PDB: 2AIA, PDB: 2AIE, PDB: 2EW5, PDB: 2EW6, and PDB: 2EW7.
== Food spoilage == Yeasts are able to grow in foods with a low pH (5.0 or lower) and in the presence of sugars, organic acids, and other easily metabolized carbon sources. During their growth, yeasts metabolize some food components and produce metabolic end products. This causes the physical, chemical, and sensible properties of a food to change, and the food is spoiled. The growth of yeast within food products is often seen on their surfaces, as in cheeses or meats, or by the fermentation of sugars in beverages, such as juices, and semiliquid products, such as syrups and jams. The yeast of the genus Zygosaccharomyces have had a long history as spoilage yeasts within the food industry. This is mainly because these species can grow in the presence of high sucrose, ethanol, acetic acid, sorbic acid, benzoic acid, and sulfur dioxide concentrations, representing some of the commonly used food preservation methods. Methylene blue is used to test for the presence of live yeast cells. In oenology, the major spoilage yeast is Brettanomyces bruxellensis. Candida blankii has been detected in Iberian ham and meat.
Sources: en.wikipedia.org
The group takes its name from Mighei (Ukraine), but the most famous member is the extensively studied Murchison meteorite. Many falls of this type have been observed and CM chondrites are known to contain a rich mix of complex organic compounds such as amino-acids and purine/pyrimidine nucleobases. CM chondrite famous falls:
== Early life == Born William Beckett on 10 September 1826, he was the third and second surviving son of Sir Edmund Beckett, 4th Baronet, of Grimthorpe, Yorkshire, and his wife Maria Beverley, daughter of William Beverley of Beverley. He was educated at Rugby School and Trinity College, Cambridge.
Embryonic Hb are expressed as early as four to six weeks of embryogenesis and disappear around the eighth week of gestation as they are replaced by fetal Hb. Embryonic Hbs include: Hb Gower-1, composed of two ζ (zeta) globins and two ε (epsilon) globins, i.e., ζ2ε2 Hb Gower-2, composed of two α globins and two ε globins (α2ε2) Hb Portland, composed of two ζ globins and two γ (gamma) globins (ζ2γ2) Fetal Hb (HbF) is produced from approximately eight weeks of gestation through birth and constitutes approximately 80 percent of Hb in the full-term neonate. It declines during the first few months of life and, in the normal state, constitutes <1 percent of total Hb by early childhood. HbF is composed of two α globins and two γ globins (α2γ2). Adult Hb (HbA) is the predominant Hb in children by six months of age and onward; it constitutes 96-97% of total Hb in individuals without a hemoglobinopathy. It is composed of two α globins and two β globins (α2β2). HbA2 is a minor adult Hb that normally accounts for approximately 2.5–3.5% of total Hb from six months of age onward. It is composed of two α globins and two δ (delta) globins (α2δ2).
Sources: en.wikipedia.org
Cardarine is a common name for GW501516, a synthetic PPARδ agonist developed for research. It has not been approved as a medication in any country. It is classified as an unapproved drug and a prohibited substance in sport.
No. Cardarine is not an anabolic steroid; it belongs to a different chemical class that targets PPARδ. Steroids act primarily through androgen receptors, while cardarine acts through a nuclear receptor involved in metabolism.
Some rodent studies reported increased endurance and changes in fat metabolism after cardarine exposure. Long-term studies in animals also raised concerns about cancer in certain tissues. Human trial data are limited, so these findings cannot be directly translated to people.
It targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not act primarily on androgen receptors. This distinction separates it from SARMs.