Investigational drug raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-11-09 and is reviewed periodically as new material appears.
Anti-doping laboratories identify GW501516 and related metabolites using liquid chromatography coupled with tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be analyzed. The method targets the parent compound and phase I and phase II metabolites, which extend the detection window. Because the substance is prohibited at all times, athletes can be tested outside competition. Detection limits and windows depend on the assay, sample type, and individual metabolism.
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
Quality assessment for cardarine samples usually combines identity, purity, and impurity testing. Nuclear magnetic resonance spectroscopy and mass spectrometry can confirm molecular structure, while high-performance liquid chromatography estimates purity. Certificates of analysis from testing laboratories may list these results, but they do not establish safety or legality. In the absence of approved manufacturing, products sold online may contain the wrong compound, variable amounts, or unlisted contaminants. Independent verification is therefore central to analytical work and to interpreting any reported biological activity.
Laboratory detection of GW501516 commonly uses liquid chromatography coupled with tandem mass spectrometry. The method can identify the parent compound or its metabolites in urine and blood after sample cleanup. Protein precipitation, solid-phase extraction, or enzymatic hydrolysis may precede analysis, depending on the matrix. Reference standards are required for accurate quantification and confirmation. Because the compound is not approved, testing often occurs in anti-doping, forensic, or research settings rather than routine clinical care. Results are reported with limits of detection and quantification.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport; not approved as medicine | Listed by WADA at all times. |
| Common synonyms | GW501516, GW-501516, endurobol | Cardarine is a colloquial name. |
| Typical analytical method | LC-MS/MS | Detects parent compound and metabolites. |
| Common test matrix | Urine | Blood and dried blood spots also possible. |
| Legal classification | Varies by country | Often treated as unapproved drug or research chemical. |
Detection of GW501516 in biological samples generally relies on liquid chromatography coupled with tandem mass spectrometry. Urine is a common matrix in anti-doping analysis, while blood or plasma may be used in research settings. Sample preparation can involve enzymatic hydrolysis, protein precipitation, or solid-phase extraction before instrumental analysis. Because the compound undergoes metabolism, assays may target the parent molecule, one or more metabolites, or both. Detection windows are not fixed; they depend on factors such as dose, route, individual metabolism, and assay sensitivity. Reference standards are required for accurate identification and quantification.
Handling and quality assessment of cardarine reference material follow general laboratory practices for poorly characterized compounds. It typically appears as a white to off-white powder and is sparingly soluble in water but soluble in organic solvents such as dimethyl sulfoxide and ethanol. Storage recommendations usually specify a cool, dry, dark place, with long-term storage at low temperature and desiccation. Purity may be checked by high-performance liquid chromatography with ultraviolet detection, while identity is confirmed by mass spectrometry and nuclear magnetic resonance. No pharmacopeial monograph exists, so reported purity and stability depend on the supplier’s methods.
Cardarine is the common name for GW501516, a synthetic compound studied as a peroxisome proliferator-activated receptor delta agonist. Researchers developed it to explore treatments for lipid disorders and metabolic conditions. It is not an approved medicine in any country. Early clinical work examined changes in HDL cholesterol and triglycerides, but development was discontinued after animal studies raised concerns about cancer. The compound remains available as a research chemical and appears in discussions of performance enhancement.
At the molecular level, GW501516 binds and activates PPARδ, a nuclear receptor that regulates transcription. Activation shifts expression of genes involved in fatty acid oxidation, energy expenditure, and lipid transport in skeletal muscle and liver. Animal studies report increased endurance and altered lipid profiles after exposure. Human data are limited to small trials and do not establish long-term safety or efficacy. PPARδ also has roles in cell proliferation, so the relationship between activation and cancer risk remains an open question.
GW501516 acts on PPARδ, a nuclear receptor that helps regulate fatty acid oxidation and energy homeostasis. In animal studies, activation of this receptor was associated with increased endurance and changes in lipid metabolism. Human trials examined effects on blood lipids and other metabolic markers, but the compound did not advance to approval. Rodent studies later reported tumors in multiple tissues at doses used in those experiments. Whether those findings translate to human risk remains uncertain, and the clinical relevance of the animal data is still debated.
Regulatory bodies treat GW501516 as a prohibited substance in competitive sport. The World Anti-Doping Agency added it to the prohibited list, and it falls under classes covering metabolic modulators and hormone-related agents. It is not approved by drug regulators for human use, and it is not a lawful dietary supplement. Products sold under the cardarine name may contain unlisted ingredients or different compounds. Because no approved product exists, quality and identity are not guaranteed by pharmaceutical manufacturing standards.
Cardarine is a common name for the investigational chemical GW501516, also written GW-1516. It was developed as a peroxisome proliferator-activated receptor delta agonist for metabolic conditions such as dyslipidemia. Early research focused on lipid handling and energy use in skeletal muscle and other tissues. The compound was never approved as a medicine. In public discussion, it is often grouped with performance-enhancing substances, although its receptor target differs from that of anabolic steroids or selective androgen receptor modulators. Regulatory and health authorities have issued warnings about its use.
Because cardarine is not an approved medicine, no pharmacopeial monograph defines its identity, purity, or storage requirements. Laboratories typically rely on in-house methods and reference standards when testing materials labeled as GW501516. Certificates of analysis may report purity and identity for a specific batch, but their scope varies and they do not guarantee safety or legal status. Independent verification can include high-performance liquid chromatography, mass spectrometry, nuclear magnetic resonance, and elemental analysis. The distinction between research chemical labeling and human use is significant because quality standards and oversight differ.
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.
In December 2000, Dutch journalist Marjon van Royen found that "because the chemical is sprayed in Colombia from planes on inhabited areas, there have been consistent health complaints [in humans]. Burning eyes, dizziness and respiratory problems being most frequently reported." In some areas, 80 percent of the children of the indigenous community fell sick with skin rashes, fever, diarrhoea and eye infections. Because the glyphosate is sprayed from the air, there is a much higher chance of human error when spraying suspected illegal coca plantations. In many cases the wrong fields are sprayed, resulting in not only a total loss of the farmer's crop- but the loss of that field altogether as nothing will grow where the herbicide has been sprayed. Though official documentation of the health effects of glyphosate spraying in Colombia are virtually non-existent, neighbouring Ecuador has conducted studies to determine the cause of mysterious illnesses amongst people living along the border of Colombia and has since demanded that no aerial sprayings occur within 10 km of the border because of the damages caused to the people, animals and environment in that area. In 2015, Colombia announced a ban on using glyphosate in these programs due to concerns about human toxicity of the chemical.
=== Metabolic pathways === Genomic analysis indicates that "Ca. M. multicellularis" has the potential to use both autotrophic and heterotrophic pathways. For autotrophic growth, it utilises the Wood–Ljungdahl pathway (also known as the reductive acetyl-coenzyme A pathway) for carbon fixation. For heterotrophy, it is able to use small organic molecules including acetate, propionate, and succinate as carbon donors and/or electron sources. "Ca. M. multicellularis" has also been found to contain a complete glycolysis pathway, a full TCA cycle and group-1 nickel-iron hydrogenases coupled to oxidative phosphorylation. As found in SCM sequencing, the consortium exhibits both genetic and metabolic differentiation. The use of nano-scale secondary ion mass spectrometry (NanoSIMS) and bioorthogonal noncanonical amino acid tagging (BONCAT) demonstrated that anabolic activity and protein synthesis is not uniform across the organism. The most active regions of protein synthesis were found to be concentrated around the acellular centre. A 2024 study suggests the potential for an internal division of labour, with certain cells metabolising specific substrates and transferring them to surrounding cells by membrane vesicles.
==== Pharmacokinetics ==== Due to high lipid solubility, cannabidiol is poorly absorbed in the intestine. The absorbed cannabidiol accumulates in adipose tissue or albumin (proteins in blood), which prolongs its elimination from the body. Most absorbed cannabidiol is converted into other metabolites by various enzymes in the liver and intestine, including CYP2C19 and CYP3A4. Cannabidiol is mainly excreted from the body with faeces.
== Etymology == The first written use of the term "vegetarian" originated in the early 19th century, when authors referred to a vegetable regimen diet. Historically, 'vegetable' could be used to refer to any type of edible vegetation. Modern dictionaries explain its origin as a compound of vegetable (adjective) and the suffix -arian (in the sense of agrarian). The term was popularized with the foundation of the Vegetarian Society in Manchester in 1847, although it has been in use since around 1839 to refer to what was previously called a vegetable regimen or diet. It was used in writing first attributed to actress, writer and abolitionist Fanny Kemble, in her Journal of a Residence on a Georgian plantation in 1838–1839. The earliest occurrences of the term seem to be related to Alcott House—a school on the north side of Ham Common, London—which was opened in July 1838 by James Pierrepont Greaves. From 1841, it was known as A Concordium, or Industry Harmony College, and the institution then began to publish its own pamphlet, The Healthian. It provides some of the earliest appearances of the term "vegetarian".
=== Bacteria and archaea === Vitamin B12 is produced in nature by certain bacteria and archaea. It is synthesized by some bacteria in the gut microbiota in humans and other animals, but it has long been thought that humans cannot absorb this as it is made in the colon, downstream from the small intestine, where the absorption of most nutrients occurs. Ruminants, such as cows and sheep, are foregut fermenters, meaning that plant food undergoes microbial fermentation in the rumen before entering the true stomach (abomasum), thus allowing them to absorb the vitamin B12 produced by the bacteria. Other mammalian species (examples: rabbits, pikas, beaver, guinea pigs) consume high-fiber plants which pass through the gastrointestinal tract and undergo bacterial fermentation in the cecum and large intestine. In this hindgut fermentation, the material from the cecum is expelled as "cecotropes" and are re-ingested, a practice referred to as cecotrophy. Re-ingestion allows for absorption of nutrients made available by bacterial fermentation, and also of vitamins and other nutrients synthesized by the gut bacteria, including vitamin B12. Non-ruminant, non-hindgut herbivores may have an enlarged forestomach and/or small intestine to provide a place for bacterial fermentation and B-vitamin production, including B12. For gut bacteria to produce vitamin B12, the animal must consume sufficient amounts of cobalt. Soil that is deficient in cobalt may result in B12 deficiency, and B12 injections or cobalt supplementation may be required for livestock.
Sources: en.wikipedia.org
=== Increase in worldwide players === Wenger was one of the first managers in English football to scout abroad for talent. His double-winning team of 1998 was described by editor Jason Cowley as "a model of racial and multicultural integration. They were the first truly globalised team". Richard Jolly writing for The National added that Wenger aided the Premier League's globalisation and "showed the merit of hiring foreign managers on the basis of their record abroad". Wenger himself felt he had changed attitudes towards foreign managers in England:
Present-day Ningxia is one of the nation's smallest provincial-level units and borders the provinces of Shaanxi and Gansu and the Inner Mongolia Autonomous Region. At 3556 meters above sea level, Aobaogeda (敖包疙瘩) in the Helan Mountains is the highest point in Ningxia. Ningxia is a relatively dry, desert-like region and features a diverse geography of forested mountains and hills, table lands, deserts, flood plains and basins cut through by the Yellow River. The Ningxia ecosystem is one of the least studied regions in the world. Significant irrigation supports the growing of wolfberries, a commonly consumed fruit throughout the region. Ningxia's deserts include the Tengger Desert in Shapotou. The northern section, through which the Yellow River flows, supports the best agricultural land. A railroad, linking Lanzhou with Baotou, crosses the region. A highway has been built across the Yellow River at Yinchuan. On 16 December 1920, the Haiyuan earthquake, 8.6 magnitude, at 36.6°N 105.32°E / 36.6; 105.32, initiated a series of landslides that killed an estimated 200,000 people. Over 600 large loess landslides created more than 40 new lakes.
=== Cancer === Meta-analyses of intervention and observational trials for various types of cancer report mixed results. Supplementation with β-carotene did not appear to decrease the risk of cancer overall, nor specific cancers including: pancreatic, colorectal, prostate, breast, melanoma, or skin cancer generally. High-dose β-carotene supplementation unexpectedly resulted in a higher incidence of lung cancer and of total mortality in people who were cigarette smokers. For dietary retinol, no effects were observed for high dietary intake and breast cancer survival, risk of liver cancer, risk of bladder cancer or risk of colorectal cancer, although the last review did report lower risk for higher β-carotene consumption. In contrast, an inverse association was reported between retinol intake and relative risk of esophageal cancer, gastric cancer, ovarian cancer, pancreatic cancer, lung cancer, melanoma, and cervical cancer. For lung cancer, an inverse association was also seen for β-carotene intake, separate from the retinol results. When high dietary intake was compared to low dietary intake, the decreases in relative risk were in the range of 15 to 20%. For gastric cancer, a meta-analysis of prevention trials reported a 29% decrease in relative risk from retinol supplementation at 1500 μg/day
The diagnosis of CSA syndrome is made when the presence of at least 5 central apnea events occur per hour. There are multiple mechanisms that drive the apnea events. In individuals with heart failure with Cheyne-Stokes respiration, the brain's respiratory control centers are imbalanced during sleep. This results in ventilatory instability, caused by chemoreceptors that are hyperresponsive to CO2 fluctuations in the blood, resulting in high respiratory drive that leads to apnea. Another common mechanism that causes CSA is the loss of the brain's wakefulness drive to breathe.
Sources: en.wikipedia.org
Legal status varies by country. It is not approved as a medicine, and it is prohibited in sport. Some jurisdictions restrict import, sale, or possession.
Laboratories use liquid chromatography-tandem mass spectrometry to detect GW501516 and its metabolites. Urine is commonly tested, and testing can occur in and out of competition.
No, cardarine is not a SARM. It is a PPARδ agonist, which acts on a different receptor. The two classes are often confused in online discussions.
LC-MS/MS is common, often after sample cleanup. The assay targets GW501516 or its metabolites.