This is a working overview of PPARδ agonist, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-07-13 and is reviewed periodically as new material appears.
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.
GW501516 binds and activates PPARδ, a nuclear receptor that influences transcription of genes involved in fatty acid oxidation and energy use. Activation shifts some metabolic pathways in preclinical models, which is why the compound has been studied for lipid disorders and exercise-related endpoints. The exact downstream effects in humans are incompletely mapped. PPARδ is expressed in many tissues, including skeletal muscle, liver, and adipose tissue, so broad activation may have varied consequences. Researchers continue to examine how selective or partial activation might alter the balance between benefits and risks.
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.
| Property | Value | Notes |
|---|---|---|
| CAS Registry Number | 317318-70-0 | Unique identifier for the compound. |
| Chemical class | PPARδ agonist | Synthetic ligand for peroxisome proliferator-activated receptor delta. |
| Appearance | White to off-white solid | Typical form of research-grade material. |
| Solubility | Soluble in DMSO and ethanol | Poorly soluble in water. |
| Typical storage | -20°C | Recommended for long-term storage of stock solutions. |
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.
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.
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.
=== Special precautions === The elderly metabolize benzodiazepines more slowly than younger people and are also more sensitive to the effects of benzodiazepines, even at similar blood plasma levels. Doses for the elderly are recommended to be about half of that given to younger adults and are to be administered for no longer than two weeks. Long-acting benzodiazepines such as clonazepam are not generally recommended for the elderly due to the risk of drug accumulation. The elderly are especially susceptible to increased risk of harm from motor impairments and drug accumulation side effects. Benzodiazepines also require special precaution if used by individuals that may be pregnant, alcohol- or drug-dependent, or may have comorbid psychiatric disorders. Clonazepam is generally not recommended for use in elderly people for insomnia due to its high potency relative to other benzodiazepines. Clonazepam is not recommended for use in those under 18. Use in very young children may be especially hazardous. Of anticonvulsant drugs, behavioural disturbances occur most frequently with clonazepam and phenobarbital. Doses higher than 0.5–1 mg per day are associated with significant sedation. Clonazepam may aggravate hepatic porphyria. Clonazepam is not recommended for patients with chronic schizophrenia. A 1982 double-blinded, placebo-controlled study found clonazepam increases violent behavior in individuals with chronic schizophrenia. Clonazepam has similar effectiveness to other benzodiazepines at often a lower dose.
== January 5, 1982 (Tuesday) == The U.N. General Assembly voted, 86 to 21 with 34 abstentions, to approve a non-binding resolution calling all members of the United Nations to end aid, trade, and diplomatic ties with Israel to punish it for annexing the Golan Heights. The U.S. used its power, as a permanent member of the UN Security Council, and vetoed the resolution on January 20. South Korea ended a nationwide curfew that had been in place since 1945, and permitted citizens the freedom to be outside from midnight to 4:00 in the morning, a period previously off limits. The curfew remained in effect, however, for areas bordering North Korea. President Chun Doo-hwan said in a statement that South Koreans were "more mature" and that the curfew was no longer necessary. The sinking of the Japanese fishing trawler Akebono Maru No.28 killed 32 members of its crew. The ship was at least 130 miles (210 km) away from Adak Island, one the Aleutian Islands off of the coast of the U.S. state of Alaska when it capsized. Serial killer Charles Jackson Jr. raped and murdered his final victim, Joan Stewart, a biology professor at San Francisco City College near Montclair, California. Jackson, suspected of murdering seven other people in the Bay Area from 1975 to 1981, would be convicted of the murder of Stewart and sentenced to life imprisonment and would die in 2002, before the extent of his killings would be revealed by DNA profiling not available in 1982. Born: Faiza Hasan, Pakistani television actress; in Karachi.
The beta carotene in carrots does not enhance night vision beyond normal levels for people receiving an adequate amount, only in those with a deficiency of vitamin A. Spinach is not a particularly good source of dietary iron. While it does contain more iron than many vegetables such as asparagus, Swiss chard, kale, or arugula, it contains only about one-third to one-fifth of the iron in lima beans, chickpeas, apricots, or wheat germ. Additionally, the non-heme iron found in spinach and other vegetables is not as readily absorbed as the heme iron found in meats and fish. Most cases of obesity are not related to slower resting metabolism. Resting metabolic rate does not vary much between people. Overweight people tend to underestimate the amount of food they eat, and underweight people tend to overestimate. In fact, overweight people tend to have faster metabolic rates due to the increased energy required by the larger body. Eating normal amounts of soy does not cause hormonal imbalance. There is no good evidence that low-carbohydrate diets have any health benefits besides weight loss, for which they are about as effective as other diets. Weight loss is primarily a result of caloric restriction, and is not significantly influenced by the balance between fat and carbohydrate in one's diet. Monosodium glutamate has not been proven to cause any negative health effects.
Sources: en.wikipedia.org
AlphaFold has been used to predict structures of proteins of SARS-CoV-2, the causative agent of COVID-19. The structures of these proteins were pending experimental detection in early 2020. Results were reviewed by scientists at the Francis Crick Institute in the United Kingdom before being released to the broader research community. The team also confirmed accurate prediction against the experimentally determined SARS-CoV-2 spike protein that was shared in the Protein Data Bank, an international open-access database, before releasing the computationally determined structures of the under-studied protein molecules. The team acknowledged that although these protein structures might not be the subject of ongoing therapeutical research efforts, they will add to the community's understanding of the SARS-CoV-2 virus. Specifically, AlphaFold 2's prediction of the structure of the ORF3a protein was very similar to the structure determined by researchers at University of California, Berkeley using cryo-electron microscopy. This specific protein is believed to assist the virus in breaking out of the host cell once it replicates. This protein is also believed to play a role in triggering the inflammatory response to the infection.
The isotopes neptunium-235, -236, and -237 are predicted to be fissile; although only neptunium-237's fissionability has been experimentally shown. Its critical mass is about 60 kg, only about 10 kg more than that of the commonly used uranium-235. Calculated values of the critical masses of neptunium-235, -236, and -237 respectively are 66.2 kg, 6.79 kg, and 63.6 kg: the neptunium-236 value is even lower than that of plutonium-239 and 236Np also has a low neutron cross section. However, a neptunium atomic bomb has never been built because uranium and plutonium have lower critical masses than 235Np and 237Np, and 236Np is difficult to purify as it is not found in quantity in spent nuclear fuel and is nearly impossible to separate in any significant quantities from 237Np.
== Controversies == In December 2016, Zydus Discovery DMCC, a research subsidiary Zydus Lifesciences, was cited by the US FDA for deliberately misbranding saroglitazar. In a December 21, 2016, letter to the company, the US FDA asked it to stop using broad statements, such as the "world's first" and to stop suggesting that the drug is approved throughout the world, including in the United States, when that is not true.
Sources: en.wikipedia.org
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.
No. Cardarine is not an anabolic steroid; it belongs to a different chemical class that targets PPARδ. Steroids act primarily through androgen receptors, while cardarine acts through a nuclear receptor involved in metabolism.
Some rodent studies reported increased endurance and changes in fat metabolism after cardarine exposure. Long-term studies in animals also raised concerns about cancer in certain tissues. Human trial data are limited, so these findings cannot be directly translated to people.
Anti-doping and clinical laboratories commonly use liquid chromatography-tandem mass spectrometry. The method can identify GW501516 and its metabolites in urine or blood. Detection depends on sample timing and the amount present.