The short version of PPAR delta fits in a sentence. The long version — which is the one that helps — is below.
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In the fitness and bodybuilding literature, cardarine is frequently discussed as an endurance agent or fat-loss compound, although such claims are not supported by robust clinical evidence. Online descriptions often mix animal data, user anecdotes, and marketing language. Researchers who study PPARδ agonists distinguish between receptor activation in controlled experiments and unsupervised use of unverified products. The latter introduces unknown purity, dose, and interactions, making reported experiences difficult to interpret scientifically.
GW501516 acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in transcription of genes related to lipid handling and energy use. Activation of PPARδ can shift skeletal muscle toward greater fatty acid oxidation in animal models, which is one reason it drew interest for metabolic disease and exercise research. The exact downstream effects depend on tissue, species, dose, and duration. Human data are sparse, so many proposed benefits remain hypotheses rather than established clinical outcomes.
Laboratory studies have examined GW501516 in cell cultures and rodents for conditions such as dyslipidemia, insulin resistance, and obesity. Some trials in humans were initiated, but development was discontinued after preclinical findings raised concerns about cancer in certain models. Those findings do not prove that the compound causes cancer in people, but they contributed to regulatory caution. Later reviews often describe the evidence as preliminary and insufficient for assessing long-term safety.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Solubility | Soluble in dimethyl sulfoxide and some organic solvents; practically insoluble in water | Solvent choice affects laboratory handling |
| Typical storage | -20 °C, desiccated, protected from light | Common condition for research samples |
| Analytical method | Liquid chromatography–tandem mass spectrometry (LC-MS/MS) | Used for identification and quantification in biological or product samples |
| Common synonyms | GW501516, GW-501516, GSK-516, Endurobol | Names found in research and anti-doping literature |
| Regulatory status | Unapproved therapeutic; prohibited in competitive sport | Status can vary by country and context |
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.
The pharmacological interest in cardarine centers on PPARδ activation and its downstream effects on lipid handling and mitochondrial function. In animal studies, PPARδ agonists have been associated with changes in exercise endurance and fatty acid utilization, though results vary by model and protocol. Human data remain sparse, and the absence of large controlled trials limits conclusions about efficacy. Researchers often describe the compound as a tool for probing PPARδ biology rather than a proven therapeutic agent.
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.
Cardarine is a common name for GW501516, a synthetic compound studied for its effects on lipid and glucose metabolism. It functions as an agonist at peroxisome proliferator-activated receptor delta, or PPARδ, a nuclear receptor that influences gene expression. The molecule is not a steroid, nor is it a selective androgen receptor modulator. It is also known in research and sports literature as GW-501516 and endurobol. Early laboratory work examined its metabolic activity in cell cultures and animal models.
Activation of PPARδ changes transcription of genes involved in fatty acid transport, mitochondrial function, and skeletal muscle fuel preference. In rodent studies, pharmacological PPARδ activation was associated with increased endurance and altered body composition. These findings generated interest in performance enhancement, but species differences and study designs limit direct extrapolation to humans. Small human trials were conducted in the 2000s and later discontinued. The extent to which cardarine produces similar metabolic or performance effects in people remains an open question.
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.
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.
In late 2025, Hollister Co. partnered with Taco Bell for a limited-edition, Y2K-inspired capsule collection. The drop, the first Hollister × Taco Bell collaboration, includes 11 pieces: vintage-style graphic tees, baggy denim, soft “Feel Good Fleece” hoodies and sweatpants, cozy socks, and a hot-sauce packet keychain accessory. The collection officially launched in Hollister stores and online on December 1, 2025, with prices ranging from US $14.95 to US $79.95, and sizes offered from XS to XL.
== Structural studies == As of late 2007, 12 structures have been solved for this class of enzymes, with PDB accession codes PDB: 1DQ8, PDB: 1DQ9, PDB: 1DQA, PDB: 1HW8, PDB: 1HW9, PDB: 1HWI, PDB: 1HWJ, PDB: 1HWK, PDB: 1HWL, PDB: 2Q1L, PDB: 2Q6B, and PDB: 2Q6C.
Radium was formerly used in self-luminous paints for watches, aircraft switches, clocks, and instrument dials and panels. A typical self-luminous watch that uses radium paint contains around 1 microgram of radium. In the mid-1920s, a lawsuit was filed against the United States Radium Corporation by five dying "Radium Girls" – dial painters who had painted radium-based luminous paint on the components of watches and clocks. The dial painters were instructed to lick their brushes to give them a fine point, thereby ingesting radium. Their exposure to radium caused serious health effects which included sores, anemia, and bone cancer. During the litigation, it was determined that the company's scientists and management had taken considerable precautions to protect themselves from the effects of radiation, but it did not seem to protect their employees. Additionally, for several years the companies had attempted to cover up the effects and avoid liability by insisting that the Radium Girls were instead suffering from syphilis. As a result of the lawsuit, and an extensive study by the U.S. Public Health Service, the adverse effects of radioactivity became widely known, and radium-dial painters were instructed in proper safety precautions and provided with protective gear. Radium continued to be used in dials, especially in manufacturing during World War II, but from 1925 onward there were no further injuries to dial painters.
==== Post-treatment isolation ==== Ablation doses are usually administered on an inpatient basis, and IAEA International Basic Safety Standards recommend that patients are not discharged until the activity falls below 1100 MBq. ICRP advice states that "comforters and carers" of patients undergoing radionuclide therapy should be treated as members of the public for dose constraint purposes and any restrictions on the patient should be designed based on this principle. Patients receiving I-131 radioiodine treatment may be warned not to have sexual intercourse for one month (or shorter, depending on dose given), and women told not to become pregnant for six months afterwards. "This is because a theoretical risk to a developing fetus exists, even though the amount of radioactivity retained may be small and there is no medical proof of an actual risk from radioiodine treatment. Such a precaution would essentially eliminate direct fetal exposure to radioactivity and markedly reduce the possibility of conception with sperm that might theoretically have been damaged by exposure to radioiodine." These guidelines vary from hospital to hospital and will depend on national legislation and guidance, as well as the dose of radiation given. Some also advise not to hug or hold children when the radiation is still high, and a one- or two- metre distance to others may be recommended. I-131 will be eliminated from the body over the next several weeks after it is given.
== Semi-finals == The draw for the semi-finals took place on 19 March 2023 on BBC One, after Brighton & Hove Albion's victory over Grimsby Town. This round, decided in one match, which was played at Wembley Stadium, included one team from the second-tier EFL Championship: Sheffield United.
Sources: en.wikipedia.org
Their feature documentary Kumu Hina, about transgender native Hawaiian teacher and cultural icon Hinaleimoana Wong-Kalu, was supported by ITVS, Pacific Islanders in Communications and the Ford Foundation and won the GLAAD Media Award for Outstanding Documentary and the Independent Lens Audience Award on PBS In 2017, Hamer and Wilson, with Hinaleimoana Wong-Kalu as producer, released Leitis in Waiting and Lady Eva, which documented the lives of transgender women in the conservative South Pacific Kingdom of Tonga. This was followed in 2019 by The Rogers, about transgender men in Samoa. These films became part of a campaign to decriminalize same-sex relationships across the Pacific. Hamer, Wilson and Wong-Kalu continued their collaboration in 2020 with the animated short film Kapaemahu, based on the hidden history of four stones on Waikiki Beach placed there as a tribute to four legendary mahu who first brought the healing arts from Tahiti to Hawaii. It premiered and won the Special Jury Prize at the Tribeca Film Festival and was shortlisted for an Oscar as Best Animated Short Film at the 93rd Academy Awards. The animated film was followed by a children's book published by Kokila, a PBS feature documentary, a multimedia exhibition at the Bishop Museum, permanent display at the Hawaiʻi Convention center, and inclusion in new interpretative signage at the Kapaemahu monument in Waikiki. The team's most recent film is Aikane, an animated short based on the Hawaiian term for intimate friends of the same sex.
The other main memorial is the SAS and Airborne Forces memorial in the cloisters at Westminster Abbey. The SAS Brigade Memorial at Sennecey-le-Grand in France commemorates the wartime dead of the Belgian, British and French SAS and recently a memorial plaque was added to the David Stirling Memorial in Scotland. There are other smaller memorials "scattered throughout Europe and in the Far East". The local church of St Martin's, Hereford has part of its graveyard set aside as an SAS memorial; over twenty SAS soldiers are buried there. There is also a wall of remembrance displaying memorial plaques to some who could not be buried, including the 18 SAS men who lost their lives in the Sea King helicopter crash during the Falklands Campaign on 19 May 1982 and a sculpture and stained glass window dedicated to the SAS. On 17 October 2017 Ascension, a new sculpture and window honouring the Special Air Service Regiment in Hereford Cathedral, was dedicated by the Bishop of Hereford at a service attended by Prince William.
Bacterial glutathione transferases (GSTs; EC 2.5.1.18) are part of a superfamily of enzymes that play a crucial role in cellular detoxification, including drugs. The primary role of GSTs is to catalyze the conjugation of glutathione (GSH) with the electrophilic centers of a wide variety of molecules. The most commonly known substrates of GSTs are xenobiotic synthetic chemicals. There are also classes of GSTs that utilize glutathione as a cofactor rather than a substrate. Often these GSTs are involved in reduction of reactive oxidative species toxic to the bacterium. Conjugation with glutathione receptors renders toxic substances more soluble, and therefore more readily exocytosed from the cell.
== Polymer-hybrid delivery systems == Coiled-coils are used as non-covalent polymer-drug conjugates to link drugs to polymer backbones. The goal of these types of systems is to attach multiple drugs to a non-toxic backbone such that drugs can be stably transported throughout the body and released at a controlled rate once at the target location. Doxorubicin, paclitaxel, and campothecin are examples of drugs typically used with polymer-drug conjugate systems. Hetero-dimeric coiled-coils motifs can be utilized in such systems, whereby one strand would be conjugated to the polymer backbone network, while the other strand would be conjugated to the drug of choice. The coiled-coils would then oligomerize, followed by the administration of the drug system into the body, whereby the stability of the coiled-coil in physiological conditions would ensure the intact delivery of the drug to the target. Upon cellular uptake at the target site, coiled-coil system would be exposed to a decrease in pH associated with the acidic environments of endosomes and lysosomes, triggering the dissociation of the coiled-coils, resulting in drug release. Dr. Harm-Anton Klok and colleagues were the first to investigate the usage of coiled coils as linkers in polymer-drug conjugate systems, whereby they utilized the parallel heterodimeric E3/K3 coiled-coil system (known for its stability at physiological pH and dissociation at pH 5, resulting in E3 homotrimers along with K3 unimers) to link cargo to a poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA)-based polymer backbone. Klok et al.
Solvents can have a powerful effect on solubility, stability, and reaction rate. A change in solvent can also allow a chemist to influence the thermodynamic or kinetic control of the reaction. Reactions proceed at different rates in different solvents due to the change in charge distribution during a chemical transformation. Solvent effects may operate on the ground state and/or transition state structures. An example of the effect of solvent on organic reactions is seen in the comparison of SN1 and SN2 reactions. Solvent can also have a significant effect on the thermodynamic equilibrium of a system, for instance as in the case of keto-enol tautomerizations. In non-polar aprotic solvents, the enol form is strongly favored due to the formation of an intramolecular hydrogen-bond, while in polar aprotic solvents, such as methylene chloride, the enol form is less favored due to the interaction between the polar solvent and the polar diketone. In protic solvents, the equilibrium lies towards the keto form as the intramolecular hydrogen bond competes with hydrogen bonds originating from the solvent.
Sources: en.wikipedia.org
It binds and activates PPARδ, a nuclear receptor that influences gene expression related to fatty acid metabolism and energy balance. This mechanism has been studied mainly in animals and cell models, not established as a safe human therapy.
No. It is not an anabolic-androgenic steroid; it is a synthetic PPARδ agonist. Because it is banned in sport, it is sometimes grouped with doping agents even though its chemical class differs from steroids.
Human data are limited and development was discontinued, so major effects and long-term risks are not well characterized. Some early studies examined metabolic markers, but they do not provide a basis for unsupervised use.
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.