This is a working overview of PPARδ, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-03-03 and is reviewed periodically as new material appears.
GW501516 acts as a selective agonist at PPARδ, a nuclear receptor that regulates transcription of genes involved in lipid handling and energy metabolism. Activation of PPARδ in preclinical models increases fatty acid oxidation, mitochondrial biogenesis, and exercise endurance in rodents. These effects have made the compound a subject of metabolic research and also a target for sport anti-doping rules. In humans, however, controlled studies are limited, and whether similar endurance or metabolic changes occur at tolerated exposures remains an open question. The receptor’s broad tissue distribution also means downstream effects may vary by organ and condition.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Visual description for typical solid reference material. |
| Solubility | Poorly soluble in water; soluble in DMSO | Solubility depends on solvent, purity, and form. |
| Storage | Cool, dry, protected from light | Long-term storage often uses low temperature and desiccant. |
| Common analytical method | LC-MS/MS | Used for detection and quantification in biological matrices. |
| Common synonyms | GW-501516; GW501516; endurobol | Naming varies among literature, vendors, and databases. |
Legal status varies by country. In some places, cardarine is controlled under medicines or psychoactive substances laws; in others, it may be sold with minimal oversight as a research chemical. Customs agencies have intercepted shipments, and several national health agencies have issued warnings about products marketed for bodybuilding or performance enhancement. The lack of a standardized pharmaceutical supply means identity, purity, and contamination levels can differ widely between samples. These factors make cardarine a regulatory and public health concern rather than a conventional prescription drug.
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.
Published human data are sparse and mostly come from early-phase trials. Those studies examined short-term changes in lipids, glucose, and exercise capacity, but they were not large enough to establish efficacy or long-term safety. Some animal experiments reported increased running endurance, yet such findings do not prove a performance benefit in people. Anti-doping laboratories detect GW501516 and its metabolites in urine or blood using liquid chromatography-tandem mass spectrometry. Detection windows depend on dose, sample type, and individual metabolism. The method is sensitive enough to identify trace residues in tested samples.
Laboratory handling focuses on identity, purity, and stability. Reference standards are typically stored cold and dry, protected from light, because solutions can degrade over time. Analytical checks may use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Impurities and related substances can be separated chromatographically and compared with a known standard. Because cardarine is not an approved drug, compendial monographs are absent, and laboratories often rely on in-house methods. Reported purity varies among unregulated products and should not be assumed from a label.
Anti-doping laboratories identify GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the usual matrix, and detection can occur after the parent compound has cleared from blood. The exact detection window depends on dose, formulation, individual metabolism, and assay sensitivity. Because the compound is prohibited at all times, athletes are subject to testing in and out of competition. Analytical methods continue to improve as new metabolites and designer analogs are characterized.
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.
== Causes == Mutations in the COL11A1, COL11A2, and COL2A1 genes cause collagenopathy, types II and XI. These genes carry instructions for the protein strands that make up type II and type XI collagen. All collagen molecules are made of three protein strands (called alpha chains). The alpha chains may be identical or different, depending on the type of collagen. Type II collagen is made by combining three copies of the alpha chain made by the COL2A1 gene. Type XI collagen, on the other hand, is composed of three different alpha chains: the products of the COL2A1, COL11A1, and COL11A2 genes. Mutations in these genes interfere with the proper assembly of type II and XI collagens or reduce the amount of these collagens. Defective or reduced numbers of collagen molecules affect the development of bones and other connective tissues, causing the signs and symptoms of the type II and XI collagenopathies.
There are 10 faculties that provide 44 areas of study, in which the language medium is mostly in Polish, with only some in English. The University of Wrocław provides Bachelor, Master, and Doctoral level programmes. The degree certificates awarded by UWr are recognised globally.
=== Breastfeeding === Paracetamol is excreted in breast milk at measurable concentrations (milk/plasma ratio approximately 1), but the amount ingested by the infant is much lower than paediatric therapeutic doses and rarely associated with clinical effects. Use during breastfeeding is considered compatible at recommended doses, with extra caution for preterm infants or infants with liver disease.
Law enforcement and intelligence agencies in a number of countries arrested alleged terrorists. British Prime Minister Tony Blair said Britain stood "shoulder to shoulder" with the United States. In a speech to Congress nine days after the attacks, which Blair attended as a guest, President Bush declared "America has no truer friend than Great Britain." Subsequently, Prime Minister Blair embarked on two months of diplomacy to rally international support for military action; he held 54 meetings with world leaders. The U.S. set up the Guantanamo Bay detention camp to hold inmates they defined as "illegal enemy combatants." The legitimacy of these detentions has been questioned by the European Union and human rights organizations. On September 25, 2001, Iran's president Mohammad Khatami, meeting British Foreign Secretary Jack Straw, said: "Iran fully understands the feelings of the Americans about the terrorist attacks in New York and Washington on September 11." He said although the American administrations had been at best indifferent about terrorist operations in Iran, the Iranians felt differently and had expressed their sympathetic feelings with bereaved Americans in the tragic incidents in the two cities.
Sources: en.wikipedia.org
The democratic groups—ON, PÚ, and PVVZ—united in early 1940 and formed the Central Committee of the Home Resistance (Ústřední výbor odboje domácího, ÚVOD). Involved primarily in intelligence gathering, the ÚVOD cooperated with a Soviet intelligence organization in Prague. Following the German invasion of the Soviet Union in June 1941, the democratic groups attempted to create a united front that would include the KSČ. Heydrich's appointment in the fall thwarted these efforts. By mid-1942, the Germans had succeeded in exterminating the most experienced elements of the Czechoslovak resistance forces. Czechoslovak forces regrouped in 1942–1943. The Council of the Three (R3)—in which the communist underground was also represented—emerged as the focal point of the resistance. The R3 prepared to assist the liberating armies of the U.S. and the Soviet Union. In cooperation with Red Army partisan units, the R3 developed a guerrilla structure. Guerrilla activity intensified with a rising number of parachuted units in 1944, leading to the establishment of partisan groups such as 1st Czechoslovak Partisan Brigade of Jan Žižka, Jan Kozina Brigade or Master Jan Hus Brigade, and especially after the formation of a provisional Czechoslovak government in Košice on 4 April 1945. "National committees" took over the administration of towns as the Germans were expelled. More than 4,850 such committees were formed between 1944 and the end of the war under the supervision of the Red Army.
For the rational design of new complexes the concept of the isolobal analogy has been found useful. Roald Hoffmann was awarded the Nobel Prize in chemistry for the development of the concept. This describes metal carbonyl fragments of M(CO)n as parts of octahedral building blocks in analogy to the tetrahedral CH3–, CH2– or CH– fragments in organic chemistry. In example dimanganese decacarbonyl is formed in terms of the isolobal analogy of two d7 Mn(CO)5 fragments, that are isolobal to the methyl radical CH•3. In analogy to how methyl radicals combine to form ethane, these can combine to dimanganese decacarbonyl. The presence of isolobal analog fragments does not mean that the desired structures can be synthesized. In his Nobel Prize lecture Hoffmann emphasized that the isolobal analogy is a useful but simple model, and in some cases does not lead to success. The economic benefits of metal-catalysed carbonylations, such as Reppe chemistry and hydroformylation, led to growth of the area. Metal carbonyl compounds were discovered in the active sites of three naturally occurring enzymes.
=== Chemical synthesis === An amine functional group −NH2 can be protected from unwanted reactions by being formed as carbamate ester residue –NHC(=O)–OR. Hydrolysis of the ester bond then produces a carbamic acid –NHC(=O)OH, which then loses carbon dioxide yielding the desired amine.
In plants, light-dependent reactions occur in the thylakoid membranes of the chloroplasts where they drive the synthesis of ATP and NADPH. The light-dependent reactions are of two forms: cyclic and non-cyclic. In the non-cyclic reaction, the photons are captured in the light-harvesting antenna complexes of photosystem II by chlorophyll and other accessory pigments (see diagram "Z-scheme"). The absorption of a photon by the antenna complex loosens an electron by a process called photoinduced charge separation. The antenna system is at the core of the chlorophyll molecule of the photosystem II reaction center. That loosened electron is taken up by the primary electron-acceptor molecule, pheophytin. As the electrons are shuttled through an electron transport chain (the so-called Z-scheme shown in the diagram), a chemiosmotic potential is generated by pumping proton cations (H+) across the membrane and into the thylakoid space. An ATP synthase enzyme uses that chemiosmotic potential to make ATP during photophosphorylation, whereas NADPH is a product of the terminal redox reaction in the Z-scheme. The electron enters a chlorophyll molecule in Photosystem I. There it is further excited by the light absorbed by that photosystem. The electron is then passed along a chain of electron acceptors to which it transfers some of its energy. The energy delivered to the electron acceptors is used to move hydrogen ions across the thylakoid membrane into the lumen.
At the end of the 1896 season, Essendon, along with seven other clubs, formed the Victorian Football League. Essendon's first VFL game was in 1897 against Geelong at Corio Oval in Geelong. Essendon won its first VFL premiership by winning the 1897 VFL finals series in a round-robin event. Essendon again won the premiership in 1901, defeating Collingwood in the Grand Final. The club won successive premierships in 1911 and 1912 over Collingwood and South Melbourne, respectively.
Sources: en.wikipedia.org
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.
Most methods use liquid chromatography with tandem mass spectrometry. Urine is common in anti-doping testing, and blood or plasma may be used in research.
Typical guidance is cool, dry, dark storage, often at low temperature and with desiccant. Stability data are limited, so storage conditions should be verified for each batch or supplier.
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.