If you have been reading about GW501516 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.
Updated 2025-07-23. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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 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.
| 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. |
Safety discussions about cardarine frequently cite rodent carcinogenicity findings reported in the 2000s. In those studies, treated animals developed tumors at multiple sites, leading sponsors to discontinue clinical development. The relevance of these findings to humans has not been resolved, but they are a major reason the compound is not approved. Current literature emphasizes uncertainty about long-term effects and the risks of unregulated use. Regulators and health agencies have not established a safe human exposure level.
Cardarine is a synthetic compound also known as GW501516, GW-501516, and sometimes endurobol. It was developed as a selective agonist of peroxisome proliferator-activated receptor delta, a nuclear receptor involved in fatty acid oxidation and energy metabolism. The compound was studied in preclinical models for metabolic and cardiovascular conditions, but it did not become a marketed human medicine. In regulatory and anti-doping contexts, it is treated as a prohibited substance rather than a licensed medicine.
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 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.
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.
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.
Although HVEC ceased accelerator production in 1981, many of its machines remain active in nuclear physics research. Several have operated continuously for more than 50 years. Beyond AMS, active accelerators are used for nuclear astrophysics (studying neutron-induced reactions relevant to stellar nucleosynthesis), ion beam analysis, radiation effects testing, and ion-atom collision physics. Four remain at U.S. national laboratories: Argonne, Brookhaven, Lawrence Livermore, and Sandia. High Voltage Engineering Europa, the former Dutch subsidiary, continues manufacturing electrostatic accelerators for research and industrial applications.
==== Chirality ==== The two different chiralities of omeprazole are both metabolized into inactive products by cytochrome P450 enzymes, but each chirality is differently inactivated by specific isozymes. Compared to the (R)-enantiomer, the (S)-enantiomer is relatively more resistant to metabolism, especially metabolism by CYP2C19 (if it's processed by CYP2C19 at all). As a result, among people with a more active version of CYP2C19 ("extensive metabolizers"), the (R) half of a dose of omeprazole is likely to perform more poorly. Conversely, among those with a less active version of CYP2C19 ("poor metabolizers"), more the (R) half is expected to survive metabolism and end up useful. The proportion of the poor metabolizer phenotype varies widely between populations, from 2.0 to 2.5% in African Americans and white Americans to >20% in Asians. Several pharmacogenomics studies have suggested that PPI treatment should be tailored according to CYP2C19 metabolism status. AstraZeneca also developed esomeprazole (Nexium) which is a eutomer, purely the (S)-enantiomer, rather than a racemate like omeprazole.
14 August – Police are investigating the deaths of two 18-year-olds who attended an event at Glasgow's SWG3 venue. 16 August – Junior doctors in Scotland have voted to accept a pay offer from the Scottish Government worth 4.5% for 2022–23 and 12.4% for 2023–24. 17 August – GMB Scotland announces that non-teaching staff in ten Scottish council areas will stage two days of strike action on 13 and 14 September. The Scottish Parliament plays host to Comedy Unleashed, starring Father Ted creator Graham Linehan, after the show is cancelled by two venues in Edinburgh. Carnbooth House, a listed building and former hotel in Glasgow, is destroyed by fire. 22 August – Broadcaster Nicky Campbell gives evidence to the Scottish Child Abuse Inquiry, where he alleges that a teacher who worked at two Edinburgh schools abused children on a "Savile scale". 23 August – Murray Foote is appointed as the SNP's new chief executive, replacing Peter Murrell. 25 August – Alexander McKellar, who killed a cyclist on a remote road in the Scottish Highlands while drink driving in September 2017 and then hid the body, is sentenced to 12 years in prison. Members of Unison in 24 of Scotland's 32 council areas vote to take industrial action after rejecting a 5.5% pay offer. 26 August – A search for the Loch Ness Monster, described as the largest in 50 years, gets underway both in the vicinity of Loch Ness itself, and through an online stream of the loch. A group of people looking for the creature subsequently claim to have heard sounds, but fail to record anything.
=== Branched polymers === A monomer with functionality of 3 or more will introduce branching in a polymer and will ultimately form a cross-linked macrostructure or network even at low fractional conversion. The point at which a tree-like topology transits to a network is known as the gel point because it is signalled by an abrupt change in viscosity. One of the earliest so-called thermosets is known as Bakelite. It is not always water that is released in step-growth polymerization: in acyclic diene metathesis or ADMET, dienes polymerize with loss of ethene.
Sources: en.wikipedia.org
HPG is synthesized from prephenate, an intermediate in the shikimic acid pathway and also a precursor to tyrosine. Prephenate is aromatized by prephenate dehydrogenase (Pdh) using NAD+ as a cofactor to produce 4-hydroxyphenylpyruvate. 4-Hydroxyphenylpyruvate is then oxidized by 4-hydroxymandelate synthase (4HmaS) using oxygen to form 4-hydroxymandelate and hydrogen peroxide. 4HmaS is a non-heme iron-dependent dioxygenase. The reaction mechanism of this unique oxidation was proposed by Choroba et al in 2000
Nearer Secret of Life." The news reached readers of The New York Times the next day; Victor K. McElheny, in researching his biography, "Watson and DNA: Making a Scientific Revolution", found a clipping of a six-paragraph New York Times article written from London and dated 16 May 1953 with the headline "Form of 'Life Unit' in Cell Is Scanned". The article ran in an early edition and was then pulled to make space for news deemed more important. (The New York Times subsequently ran a longer article on 12 June 1953). The university's undergraduate newspaper Varsity also ran its own short article on the discovery on Saturday 30 May 1953. Bragg's original announcement of the discovery at a Solvay conference on proteins in Belgium on 8 April 1953 went unreported by the British press. In a seven-page, handwritten letter to his son at a British boarding school on 19 March 1953 Crick explained his discovery, beginning the letter "My Dear Michael, Jim Watson and I have probably made a most important discovery". The letter was put up for auction at Christie's New York on 10 April 2013 with an estimate of $1 to $2 million, eventually selling for $6,059,750, the largest amount ever paid for a letter at auction. Sydney Brenner, Jack Dunitz, Dorothy Hodgkin, Leslie Orgel, and Beryl M Oughton, were some of the first people in April 1953 to see the model of the structure of DNA, constructed by Crick and Watson; at the time they were working at Oxford University's Chemistry Department.
== Pharmacokinetics == Acebutolol is well absorbed from the GI tract, but undergoes substantial first-pass-metabolization, leading to a bioavailability of only 35% to 50%. Peak plasma levels of acebutolol are reached within 2 to 2.5 hours after oral dosing. Peak levels of the main active metabolite, diacetolol, are reached after 4 hours. Acebutolol has a half-life of 3 to 4 hours, and diacetolol a half-life of 8 to 13 hours. Acebutolol undergoes extensive hepatic metabolization resulting in the desbutyl amine acetolol which is readily converted into diacetolol. Diacetolol is as active as acebutolol (equipotency) and appears to have the same pharmacologic profile. Geriatric patients tend to have higher peak plasma levels of both acebutolol and diacetolol and a slightly prolonged excretion. Excretion is substantially prolonged in patients with renal impairment, and so a dose reduction may be needed. Liver cirrhosis does not seem to alter the pharmacokinetic profile of the parent drug and metabolite.
Biohazardous safety issues are identified with specified labels, signs and paragraphs established by the American National Standards Institute (ANSI). Today, ANSI Z535 standards for biohazards are used worldwide and should always be used appropriately within ANSI Z535 Hazardous Communications (HazCom) signage, labeling and paragraphs. The goal is to help workers rapidly identify the severity of a biohazard from a distance and through colour and design standardization. Biological hazard symbol design:
DNA polymerase III holoenzyme is the primary enzyme complex involved in prokaryotic DNA replication. It was discovered by Thomas Kornberg (son of Arthur Kornberg) and Malcolm Gefter in 1970. The complex has high processivity (i.e. the number of nucleotides added per binding event) and, specifically referring to the replication of the E. coli genome, works in conjunction with four other DNA polymerases (Pol I, Pol II, Pol IV, and Pol V). Being the primary holoenzyme involved in replication activity, the DNA Pol III holoenzyme also has proofreading capabilities that corrects replication mistakes by means of exonuclease activity reading 3'→5' and synthesizing 5'→3'. DNA Pol III is a component of the replisome, which is located at the replication fork. The replisome is composed of the following:
Sources: en.wikipedia.org
== Successors == A trailer for a sequel, Frontline Force II: Defiance, was released in January 2003. In December 2004, Frontline Force 2.0 was cancelled and development was moved to Source engine. The unfinished version of 2.0 was still released on the official website. In April 2005, the new mod was revealed as Front Line Force: Classic. A more tactical version of Frontline Force, titled Frontline: Tactics, was in development as a Half-Life mod in 2001. By 2007 its development was moved to Source engine under the title Frontline Force: Tactics.
21 May – IBM announces that it will begin development of a 100,000-qubit quantum computer, the world's largest and most powerful, to be completed by 2033. 22 May – A study quantifies "the human cost of global warming", showing current policies "leading to around 2.7 °C global warming could by 2080–2100 leave one-third (22–39%)" of people outside their climate niche (see also 4 May 2020) – humans' long-time range of mean annual temperatures to which their physiology may have largely adapted to. It indicates meeting the 1.5 °C goal would decrease the population exposed to unprecedented heat ~5-fold and ties itself to earlier research by initially noting that quantifying the social cost of carbon in monetary terms, as related or economics studies tend to do, may be inadequate. 23 May Using the Hubble Space Telescope and Gaia spacecraft, an analysis of proper motions of the closest known globular cluster, Messier 4, reveals an excess mass of roughly 800 solar masses in the center. This appears to not be extended, and could thus be the best kinematic evidence for an intermediate-mass black hole (even if an unusually compact cluster of compact objects, white dwarfs, neutron stars or stellar-mass black holes cannot be completely discounted). A study identifies plastic chopping boards as a substantial source of ingested microplastics. Researchers show plastic recycling facilities are a major source of microplastic water pollution (1 May).
=== Characterization of interfaces and surfactant layers === Interfacial and surface tension can be characterized by classical methods such as the -pendant or spinning drop method. Dynamic surface tensions, i.e. surface tension as a function of time, can be obtained by the maximum bubble pressure apparatus The structure of surfactant layers can be studied by ellipsometry or X-ray reflectivity. Surface rheology can be characterized by the oscillating drop method or shear surface rheometers such as double-cone, double-ring or magnetic rod shear surface rheometer.
For instance, the bulk modulus of a material is dependent on the form of its lattice, its behavior under expansion, as well as the vibrations of the molecules, all of which are dependent on temperature.
=== Ridge preservation === Ridge preservation (Colloquially Socket preservation), a procedure to reduce bone loss after tooth extraction to preserve the dental alveolus (containing the tooth socket) in the alveolar bone. A platelet-rich fibrin (PRF) membrane containing bone growth enhancing elements can be stitched over the wound or a graft material or scaffold is placed in the socket of an extracted tooth at the time of extraction. The socket is then directly closed with stitches or covered with a non-resorbable or resorbable membrane and sutured.
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.
Cardarine is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.