PPARδ agonist comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2026-03-10. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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 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.
| 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. |
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.
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.
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.
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.
Anti-doping laboratories detect GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be used in some programs. Detection depends on factors such as dose, timing, metabolism, and the sensitivity of the assay. Published methods describe limits of detection in the low nanogram per milliliter range for related compounds. Exact detection windows are not fixed for all situations and remain an area of ongoing study.
== Production and properties == Butyl acrylate can be produced by the acid-catalyzed esterification of acrylic acid with butanol. It polymerizes easily, therefore commercial preparations contain polymerization inhibitors such as hydroquinone, phenothiazine, or hydroquinone ethyl ether.
=== Genetics === Genetics plays a major role in fibromyalgia and may explain up to 50% of disease susceptibility. Fibromyalgia is potentially associated with polymorphisms of genes in the serotonergic, dopaminergic and catecholaminergic systems. Several genes have been suggested as candidates for susceptibility to fibromyalgia. These include a coding variation in Huntingtin, SLC6A4, TRPV2, MYT1L, NRXN3, and the 5-HT2A receptor 102T/C polymorphism. The heritability of fibromyalgia is estimated to be higher in patients younger than 50. Nearly all the genes suggested as potential risk factors for fibromyalgia are associated with neurotransmitters and their receptors.
This will continue, until both flows reach a similar dilution, with a concentration somewhere close to midway between the two original dilutions. Once that happens, there will be no more flow between the two tubes, since both are at a similar dilution and there is no more osmotic pressure.
Sources: en.wikipedia.org
=== Lithium-ion batteries === Li2TiO3 is used in the cathode of some lithium-ion batteries, along with an aqueous binder and a conducting agent. Li2TiO3 is used because it is capable of stabilizing the high capacity cathode conducting agents; LiMO2 (M=Fe, Mn, Cr, Ni). Li2TiO3 and the conduction agents (LiMO2) are layered in order to create the cathode material. These layers allow for the occurrence of lithium diffusion.
=== Pharmacodynamics === Benorterone is an antiandrogen, or an antagonist of the androgen receptor (AR), the biological target of the androgen sex hormones testosterone and dihydrotestosterone. In one study, the affinity of benorterone for the AR was found to be about 5-fold greater than that of cyproterone acetate in rat prostate cytosol; the Ki values were 0.7 nM for benorterone and 3.7 nM for cyproterone acetate, which were 243% and 46% of those of testosterone (Ki = 1.7 nM), respectively. However, another study found that benorterone had only 11% of the affinity of dihydrotestosterone for the androgen receptor. Although an antiandrogen, benorterone actually is a very weak partial agonist of the AR and has been reported to possess weak androgenic activity. The same is true for cyproterone acetate and other steroidal antiandrogens. Unlike certain other steroidal antiandrogens such as cyproterone acetate, benorterone is not also a progestogen, instead being described as a selective and pure AR antagonist similarly to nonsteroidal antiandrogens such as flutamide and bicalutamide. However, although it is described as not being a progestogen, benorterone was found to produce "a highly variable decrease in plasma testosterone levels," indicating that it has weak antigonadotropic effects. The reasons for this are unclear, as other pure antiandrogens such as cyproterone (not cyproterone acetate) and flutamide do not do this and instead produce consistent increases in testosterone levels.
M. oleifera is a fast-growing, deciduous tree that can reach a height of 10–12 m (33–39 ft) and trunk diameter of 46 cm (18 in). The bark has a whitish-gray color and is surrounded by thick cork. Young shoots have purplish or greenish-white, hairy bark. The tree has an open crown of drooping, fragile branches, and the leaves build up a feathery foliage of tripinnate leaves. The flowers are fragrant and hermaphroditic, surrounded by five unequal, thinly veined, yellowish-white petals. The flowers are about 1–1.5 cm (3⁄8–5⁄8 in) long and 2 cm (3⁄4 in) broad. They grow on slender, hairy stalks in spreading or drooping flower clusters, which have a length of 10–25 cm (4–10 in). Flowering begins within the first six months of planting. In seasonally cool regions, flowering only occurs once a year in late spring and early summer (Northern Hemisphere between April and June, Southern Hemisphere between October and December). In more constant seasonal temperatures and with constant rainfall, flowering can happen twice or even all year-round. The fruit is a hanging, three-sided, brown, 20–45 cm (8–17+1⁄2 in) capsule, which holds dark brown, globular seeds with a diameter around 1 cm. The seeds have three whitish, papery wings and are dispersed by wind and water.
Sources: en.wikipedia.org
== COVID-19 pandemic == ADLM members who are frontline laboratory specialists also encounter significant challenges in carrying out such studies. Lack of product selection and research materials as well as personal protective equipment, known as PPE, are the most important of these barriers. In recognition of these obstacles to optimizing research ability, ADLM sent a letter to the Coronavirus Task Force advising the Task Force and White House to minimize supply chain issues, and to identify and organize tools such that doctors, nurses, laboratory personnel and other healthcare staff may do their jobs. ADLM has produced instructional videos demonstrating serology, treatment of polymerase chain reaction (PCR), and more through research in the spotlight during the COVID-19 pandemic.
=== Mixed with polyketides === Due to the similarity with polyketide synthases (PKS), many secondary metabolites are, in fact, fusions of NRPs and polyketides. In essence, this occurs when PK modules follow NRP modules, and vice versa. This is possible because the carrier domains (PCP/ACP) are quite similar between each other and they use a similar "chain-flipping" action to access the growing substrate. Although there is high degree of similarity between the Carrier (PCP/ACP) domains of both types of synthetases, the mechanism of condensation is different from a chemical standpoint:
When T. rex was first discovered, the humerus was the only element of the forelimb known. For the initial mounted skeleton as seen by the public in 1915, Osborn substituted longer, three-fingered forelimbs like those of Allosaurus. A year earlier, Lawrence Lambe described the short, two-fingered forelimbs of the closely related Gorgosaurus. This strongly suggested that T. rex had similar forelimbs, but this hypothesis was not confirmed until the first complete T. rex forelimbs were identified in 1989, belonging to MOR 555 (the "Wankel rex"). The remains of Sue also include complete forelimbs. T. rex arms are very small relative to overall body size, measuring only 1 meter (3.3 ft) long, and some scholars have labelled them as vestigial. However, the bones show large areas for muscle attachment, indicating considerable strength. This was recognized as early as 1906 by Osborn, who speculated that the forelimbs may have been used to grasp a mate during copulation. Newman (1970) suggested that the forelimbs were used to assist Tyrannosaurus in rising from a prone position. Since then, other functions have been proposed, although some scholars find them implausible. Padian (2022) argued that the reduction of the arms in tyrannosaurids did not serve a particular function but was a secondary adaptation, stating that as tyrannosaurids developed larger and more powerful skulls and jaws, the arms got smaller to avoid being bitten or torn by other individuals, particularly during group feedings.
== Classification == The enzyme subclasses designate the types of components that are being transferred, and the sub-subclasses indicate the reaction processes that provide the driving force for the translocation.
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 targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.