Nuclear receptor raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-02-21 and is reviewed periodically as new material appears.
Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.
Regulatory treatment varies, but cardarine is not approved as a medicine. Sports authorities list GW501516 as a prohibited substance, and it is banned at all times under the World Anti-Doping Agency code. Many countries restrict sales for human consumption, while online vendors market it as a research chemical. Such products may lack purity data, and their actual contents can differ from the label. Purchasing or possessing cardarine may carry legal consequences depending on jurisdiction. The compound is not a dietary supplement ingredient in regulated markets.
Clinical development stopped after rodent studies showed tumors at multiple sites. Whether those findings predict human cancer risk remains an open question, but they led sponsors to discontinue programs. Human safety data are limited to small, short-term studies that were not designed to assess cancer risk. Reported effects in those studies included changes in blood lipids, but the evidence is insufficient for medical use. Long-term consequences of nonmedical use are not well characterized. Questions about dose, duration, and individual susceptibility remain unresolved.
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.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | GW501516; GW-1516; endurobol | GW501516 is the research code |
| Drug class | PPARδ agonist | Not a selective androgen receptor modulator |
| Molecular formula | C21H18F3NO3S2 | Established chemical formula |
| Molar mass | 453.5 g/mol | Calculated from the formula |
| Regulatory status | Prohibited in sport; not approved as medicine | Status varies by country |
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.
The compound is typically described as a laboratory compound rather than a therapeutic product. Published reports have explored its role in lipid disorders, insulin sensitivity, and exercise metabolism, yet no major drug regulator has approved it for medical use. Commercial samples sold under the cardarine name may vary in purity and identity. Analytical confirmation is therefore necessary when the material is discussed in scientific or regulatory contexts. Its classification as a prohibited substance in sport further shapes how it is studied and reported.
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.
=== CNBC documentary and lawsuit === In December 2010 lawyers from Cold Stone Creamery threatened a lawsuit over some of the contents of a then-upcoming documentary by CNBC. Behind the Counter: The Untold Story of Franchising reported on the failures and successes of franchising. After several edits the program was broadcast on CNBC on March 21, 2011. Brands such as Dunkin' Donuts and Five Guys were highlighted as successful franchise brands. Cold Stone Creamery's executives and corporate lawyers were interviewed. The lawsuit was discussed with former franchisees and the litigation threats with CNBC. An apparently successful Cold Stone franchise was also featured. Another expose was not aired due to threats of litigation and stores that were closed for years appeared on search engines for some unknown reason.
== Reception == George R.R. Martin praised Considine's performance as Viserys on his personal blog, as the actor "gives the character a tragic majesty that my book Viserys never quite achieved". In an interview with GQ, Considine recalled that Martin had sent him a text which read: "Your Viserys is better than my Viserys". Critics have responded positively to Viserys' characterization, considering him to be one of the series’ most emotionally resonant characters. Ben Lindberg of The Ringer describes Viserys as the "most relatable" character in the show's ensemble, as his simple desires such as hosting tournaments and building a model of Valyria made him "much closer to the common man". Lindberg also emphasizes that Viserys was committed to his duty as king despite facing challenges, with his motivations being "love and responsibility" rather than "self-interest and thirst for personal power". Academic commentary has examined audience reactions to Viserys through the lens of disability studies. Marty Heath, an assistant professor at Nazareth University, notes that the audience's reaction to Viserys' declining health evolves "from disgust and derision to laughter and eventually wonder and appreciation", reflecting "broader cultural attitudes toward disability".
The NIH Office of the Director is the central office responsible for setting policy for the NIH, and for planning, managing, and coordinating the programs and activities of all NIH components. The NIH Director plays an active role in shaping the agency's activities and outlook. The Director is responsible for providing leadership to the Institutes and Centers by identifying needs and opportunities, especially in efforts involving multiple Institutes. Within the Director's Office is the Division of Program Coordination, Planning and Strategic Initiatives with 12 divisions including:
=== Purpose === The purpose of studying the proteome is to better understand the activity of proteins at the single-cell level. Since proteins are responsible for determining how the cell acts, understanding the proteome of single cells gives the best understanding of how a cell operates, and how gene expression changes in a cell due to different environmental stimuli. Although transcriptomics has the same purpose as proteomics it is not as accurate at determining gene expression in cells as it does not take into account post-transcriptional regulation (not all messenger RNA transcripts are actually translated into proteins). Transcriptomics is still important, of course, as studying the difference between RNA levels and protein levels can give insight regarding which genes are post-transcriptionally regulated.
Sources: en.wikipedia.org
As a small open economy, Denmark is very dependent on its foreign trade. In 2017, the value of total exports of goods and services made up 55% of GDP, whereas the value of total imports amounted to 47% of GDP. Trade in goods made up slightly more than 60% of both exports and imports, and trade in services the remaining close to 40%. Machinery, chemicals and related products like medicine and agricultural products were the largest groups of export goods in 2017. Service exports were dominated by freight sea transport services from the Danish merchant navy. Most of Denmark's most important trading partners are neighbouring countries. The five main importers of Danish goods and services in 2017 were Germany, Sweden, United Kingdom, United States and Norway. The five countries from which Denmark imported most goods and services in 2017 were Germany, Sweden, the Netherlands, China and United Kingdom. After having almost consistently an external balance of payments current account deficit since the beginning of the 1960s, Denmark has maintained a surplus on its BOP current account for every year since 1990, with the single exception of 1998. In 2017, the current account surplus amounted to approximately 8% of GDP. Consequently, Denmark has changed from a net debtor to a net creditor country. By 1 July 2018, the net foreign wealth or net international investment position of Denmark was equal to 64.6% of GDP, Denmark thus having the largest net foreign wealth relative to GDP of any EU country.
The particle size of the stationary phase is generally finer in flash column chromatography than in gravity column chromatography. For example, one of the most widely used silica gel grades in the former technique is mesh 230 – 400 (40 – 63 μm), while the latter technique typically requires mesh 70 – 230 (63 – 200 μm) silica gel.
== Stages and timeline == Formulation studies include developing a preparation of the drug which is both stable and acceptable to the patients. For orally administered drugs, this usually implies incorporating the drug in a tablet or a capsule. It is important to make the distinction that a tablet contains a variety of other potentially inert substances apart from the drug itself, and studies have to be carried out to ensure that the encapsulated drug is compatible with these other substances in a way that does not cause harm, whether direct or indirect. Preformulation involves the characterization of a drug's physical, chemical, and mechanical properties in order to choose what other ingredients (excipients) should be used in the preparation. In dealing with protein pre-formulation, the important aspect is to understand the solution behavior of a given protein under a variety of stress conditions such as freeze/thaw, temperature, shear stress among others to identify mechanisms of degradation and therefore its mitigation. Formulation studies then consider such factors as particle size, polymorphism, pH, and solubility, as all of these can influence bioavailability and hence the activity of a drug. The drug must be combined with inactive ingredients by a method that ensures that the quantity of drug present is consistent in each dosage unit e.g. each tablet. The dosage should have a uniform appearance, with an acceptable taste, tablet hardness, and capsule disintegration. It is unlikely that formulation studies will be complete by the time clinical trials start.
Sources: en.wikipedia.org
No. Cardarine is GW501516, a PPARδ agonist, while SARMs act on androgen receptors. The two classes are often grouped in informal discussions despite different mechanisms.
No. It has no approved medical indication in any country. Regulatory agencies have not cleared it for treatment or prevention of any condition.
Early clinical work stopped after rodent carcinogenicity findings. Those animal results raised concerns about long-term human risk, although direct human evidence is lacking. The human relevance of the tumors remains an open scientific question.
It binds to and activates PPAR delta, a nuclear receptor that controls expression of genes related to fatty acid oxidation. This mechanism can alter energy metabolism in animal models. It is not a direct stimulant or fat-burning enzyme.