If you have been reading about Anti-doping and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-09-22. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Common name | Cardarine | Common internet and media name. |
| Research code | GW501516 | Also written GW-1516. |
| Drug class | PPARδ agonist | Not a selective androgen receptor modulator. |
| Development status | Discontinued | Clinical development halted after rodent cancer findings. |
| Regulatory status | Prohibited in sport | Listed by WADA; not approved as medicine. |
GW501516 acts as a ligand for PPAR delta, a nuclear receptor that regulates transcription of genes involved in fatty acid oxidation and energy use. Activation of this receptor in skeletal muscle shifts metabolism toward fat burning in animal models. The compound does not burn fat directly; it changes gene expression over hours to days. Researchers study it to understand metabolic flexibility and exercise adaptation. Effects observed in rodents are not automatically expected in humans.
Preclinical research reported that GW501516 increased running endurance in mice and improved lipid profiles in some animal species. Early human trials explored effects on high-density lipoprotein cholesterol, triglycerides, and glucose handling, but the program was discontinued. Published human data are sparse and do not establish efficacy for any condition. Studies also examined PPAR delta in cancer biology, with conflicting findings across models. The relationship between receptor activation, tissue context, and disease risk remains an active area of investigation.
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.
Cardarine is a common name for GW501516, also GW-1516, a synthetic compound developed as a peroxisome proliferator-activated receptor delta (PPARδ) agonist. It belongs to a class of agents that modulate gene transcription related to lipid and energy metabolism. The compound was studied in preclinical and early clinical research for metabolic and cardiovascular conditions, but it did not progress to approved therapeutic use. Its name appears in fitness and sports contexts despite not being approved as a drug.
PPARδ is a nuclear receptor that influences transcription of genes involved in fatty acid oxidation, lipid transport, and energy homeostasis. GW501516 binds and activates this receptor with high selectivity relative to PPARα and PPARγ in laboratory assays. Activation alters expression of target genes in skeletal muscle, liver, and adipose tissue in animal models. The exact clinical consequences of these changes in humans remain incompletely characterized, and observed effects in animals do not establish therapeutic benefit or safety.
Published studies have examined GW501516 in animal models of obesity, insulin resistance, and exercise endurance. Early human trials reportedly ended, and development was discontinued after preclinical findings raised concerns about cancer in some rodent studies. Regulatory agencies have not approved cardarine for any medical use. Its availability through non-pharmaceutical channels raises questions about identity, purity, and legal status that are separate from its laboratory pharmacology. Those questions are often addressed through analytical testing rather than assumptions about product labels.
Cardarine is not approved for human therapeutic use in any major jurisdiction. It appears on the World Anti-Doping Agency Prohibited List as a PPARδ agonist within the hormone and metabolic modulators category. Sports organizations test for it because it has been detected in athlete samples and seized products. Regulatory actions against marketed research chemical versions have occurred in several countries, though enforcement varies. Availability through unregulated channels complicates oversight.
Analytical laboratories typically identify cardarine and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is a common matrix in anti-doping testing, while blood and tissue may be used in research settings. Detection windows depend on the assay, the sample matrix, and the compound's metabolism. Because cardarine is extensively metabolized, laboratories often target specific metabolites to improve sensitivity and confirmation. Reference standards are required for reliable quantification. Method validation includes checks for selectivity, linearity, and carryover.
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
==== US cinema ==== The Americans took advantage of their pre-existing cinematic advantage over the Soviet Union, using movies as another way to create the Communist enemy. In the early years of the Cold War (between 1948 and 1953), seventy explicitly anti-communist films were released. American films incorporated a wide scale of Cold War themes and issues into all genres of film, which gave American motion pictures a particular lead over Soviet film. Despite the audiences' lack of zeal for Anti-Communist/Cold War related cinema, the films produced evidently did serve as successful propaganda in both the United States and the Soviet Union. The films released during this time received a response from the Soviet Union, which subsequently released its own array of films to combat the depiction of the Communist threat. Several organizations played a key role in ensuring that Hollywood acted in the national best interest of the US, like the Catholic Legion of Decency and the Production Code Administration, which acted as two conservative groups that controlled a great deal of the national repertoire during the early stages of the Cold War. These groups filtered out politically subversive or morally questionable movies. More blatantly illustrating the shift from cinema as an art form to cinema as a form of strategic weapon, the Motion Picture Alliance for the Preservation of American Ideals ensured that filmmakers adequately expressed their patriotism.
== Technology == A Zydis tablet is produced by lyophilizing or freeze-drying the drug in a matrix usually consisting of gelatin. The resulting product is very lightweight and fragile, and must be dispensed in a special blister pack. Amipara et al., in their article "Oral disintirating tablet of antihypertensive drug" explain the technology's limitations:
Stable isotope labeling involves the use of non-radioactive isotopes that can act as tracers used to model several chemical and biochemical systems. The chosen isotope can act as a label on that compound that can be identified through nuclear magnetic resonance (NMR) and mass spectrometry (MS). Some of the most common stable isotopes are 2H, 13C, 15N, and 18O, which can further be produced into NMR solvents, amino acids, nucleic acids, lipids, common metabolites and cell growth media. The compounds produced using stable isotopes are either specified by the percentage of labeled isotopes (that is, 30% uniformly labeled 13C glucose contains a mixture that is 30% labeled with 13C isotope and 70% naturally labeled carbon) or by the specifically labeled carbon positions on the compound (that is, 1-13C glucose which is labeled at the first carbon position of glucose). A network of reactions adopted from the glycolysis pathway and the pentose phosphate pathway is shown in which the labeled carbon isotope rearranges to different carbon positions throughout the network of reactions. The network starts with fructose 6-phosphate (F6P), which has six carbon atoms with a label 13C at carbon positions 1 and 2. 1,2-13C F6P becomes two glyceraldehyde 3-phosphate (G3P), one 2,3-13C T3P and one unlabeled T3P. The 2,3-13C T3P can now be reacted with sedoheptulose 7-phosphate (S7P) to form an unlabeled erythrose 4-phosphate(E4P) and a 5,6-13C F6P. The unlabeled T3P will react with the S7P to synthesize unlabeled products.
Sources: en.wikipedia.org
285: 483-488, 2001) Molecular Pathomechanisms and New Trends in Drug Research (editor and co-author CRC Press Taylor and Frances Group, 2003) Drug discovery in the kinase inhibitory field using the Nested Chemical Library (TM) technology (co-author, ASSAY AND DRUG DEVELOPMENT TECHNOLOGIES 3: 543-551, 2005) Nuclear translocation of the tumor marker pyruvate kinase M2 induces programmed cell death (co-author, CANCER RESEARCH 67:1602-1608, 2007) AXL is a potential target for therapeutic intervention in breast cancer progression (co-author, CANCER RESEARCH 68:1905-1915, 2008) Kinase-selective enrichment enables quantitative phosphoproteomics of the kinome across the cell cycle (co-author, MOLECULAR CELL 31:438-448, 2008) Proteomics strategy for quantitative protein interaction profiling in cell extracts (co-author, NATURE METHODS 6: 741-744, 2009) Integrating molecular diagnostics into anticancer drug discovery (co-author NATURE REVIEWS DRUG DISCOVERY 9:(523-535, 2010) Development of a Cell Selective and Intrinsically Active Multikinase Inhibitor Bioconjugate (co-author, BIOCONJUGATE CHEMISTRY 22:540-545,2011) Interaction of the EGFR inhibitors gefitinib, vandetanib, pelitinib and neratinib with the ABCG2 multidrug transporter: Implications for the emergence and reversal of cancer drug resistance BIOCHEMICAL PHARMACOLOGY 84: 260-267, 2012 Developing FGFR4 inhibitors as potential anticancer agents via in silico design, supported by in vitro and cellbased (co-author CURRENT MEDICINAL CHEMISTRY 20:1203-1217, 2013
The endocrine system consists of the principal endocrine glands: the pituitary, thyroid, adrenals, pancreas, parathyroids, and gonads, but nearly all organs and tissues produce specific endocrine hormones as well. The endocrine hormones serve as signals from one body system to another regarding an enormous array of conditions, resulting in variety of changes of function.
== Clinical significance == Variants of PCSK9 can reduce or increase circulating cholesterol. LDL-particles are removed from the blood when they bind to LDLR on the surface of cells, including liver cells, and are taken inside the cells. When PCSK9 binds to an LDLR, the receptor is destroyed along with the LDL particle. PCSK9 degrades LDLR by preventing the hairpin conformational change of LDLR. If PCSK9 does not bind, the receptor will return to the surface of the cell and can continue to remove LDL-particles from the bloodstream. Other variants are associated with a rare autosomal dominant familial hypercholesterolemia (HCHOLA3). The mutations increase its protease activity, reducing LDLR levels and preventing the uptake of cholesterol into the cells. In humans, PCSK9 was initially discovered as a protein expressed in the brain. However, it has also been described in the kidney, the pancreas, liver and small intestine. Recent evidence indicate that PCSK9 is highly expressed in arterial walls such as endothelium, smooth muscle cells, and macrophages, with a local effect that can regulate vascular homeostasis and atherosclerosis. Accordingly, it is now very clear that PCSK9 has pro-atherosclerotic effects and regulates lipoprotein synthesis. As PCSK9 binds to LDLR, which prevents the removal of LDL-particles from the blood plasma, several studies have determined the potential use of PCSK9 inhibitors in the treatment of hyperlipoproteinemia (commonly called hypercholesterolemia).
Sources: en.wikipedia.org
a reactive negative-feedback system, a reactive feed-forward system, and a predictive or circadian system, The reactive negative-feedback system refers to the system that induces renal secretion of potassium in response to a rise in the plasma potassium (potassium ingestion, shift out of cells, or intravenous infusion). The reactive feed-forward system refers to an incompletely understood system that induces renal potassium secretion in response to potassium ingestion prior to any rise in the plasma potassium. This is probably initiated by gut cell potassium receptors that detect ingested potassium and trigger vagal afferent signals to the pituitary gland. The predictive or circadian system increases renal secretion of potassium during mealtime hours (e.g. daytime for humans, nighttime for rodents) independent of the presence, amount, or absence of potassium ingestion. It is mediated by a circadian oscillator in the suprachiasmatic nucleus of the brain (central clock), which causes the kidney (peripheral clock) to secrete potassium in this rhythmic circadian fashion.
=== High-pressure reserve gas === An alternative to a low-pressure compressor for gas supply is high-pressure gas storage cylinders feeding through a pressure regulator which will be set to the required supply pressure for the depth and equipment in use. In practice HP storage may be used for either reserve gas supply or both main and reserve gas supplies to a gas panel. High-pressure bulk cylinders are quiet in operation and provide gas of known quality (if it has been tested). This allows the relatively simple and reliable use of nitrox mixtures in surface-supplied diving. Bulk cylinders are also quiet in operation compared to a low-pressure compressor, but have the obvious limitation of amount of gas available. The usual configurations for surface-supplied bulk gas storage are large single cylinders of around 50 litres water capacity, often referred to as "J"s or "bombs", "quads", which are a group (sometimes, but not necessarily four in number) of similar cylinders mounted on a frame and connected together to a common supply fitting, and "kellys" which are a group of "gas storage tubes" (long large volume seamless transportable gas storage pressure vessels, with water capacity between 150 litres (5.3 cu ft) and 3,000 litres (110 cu ft)) usually mounted in a container frame or trailer, and usually connected together to a manifold with a common connection fitting.
Plants communicate with each other through both airborne and below-ground chemical cues. For example, when damaged by an herbivore, many plants emit an altered bouquet of volatile organic compounds (VOCs). Various C6 fatty acids and alcohols (sometimes known as green leaf volatiles) are often emitted from damaged leaves, since they are break-down products of plant cell membranes. These compounds (familiar to many as the smell of freshly mown grass) can be perceived by neighboring plants where they may trigger the induction of plant defenses. It is debated to what extent this communication reflects a history of active selection due to mutual benefit as opposed to "eavesdropping" on cues unintentionally emitted by neighboring plants.
A distinctive abnormality in skeletal muscle fibres on the cellular level; observable via light microscope Symptoms of muscle weakness and hypotonia Is a congenital disorder, meaning it occurs during development and symptoms present themselves at birth or in early life. Is a genetic disorder.
Sources: en.wikipedia.org
No. Cardarine is a PPARδ agonist, while selective androgen receptor modulators act on androgen receptors. The two classes differ in receptor target and downstream effects.
Preclinical rodent studies reported cancers, including liver and bladder tumors, at tested doses. The human relevance of those findings is uncertain, but development was discontinued. No approved human product resulted.
No. It remains an investigational compound without approved therapeutic labeling. Sports regulators prohibit its use, and health agencies have warned against consuming it.
Anti-doping laboratories typically use LC-MS/MS to detect GW501516 and its metabolites in urine. The method is sensitive and can identify the compound at low concentrations. Detection depends on sample timing, metabolism, and the specific assay.