Nuclear receptor is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-08-01. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
Published studies have examined GW501516 in animal models of obesity, insulin resistance, and exercise endurance. Early human trials reportedly ended, and development was discontinued after preclinical findings raised concerns about cancer in some rodent studies. Regulatory agencies have not approved cardarine for any medical use. Its availability through non-pharmaceutical channels raises questions about identity, purity, and legal status that are separate from its laboratory pharmacology. Those questions are often addressed through analytical testing rather than assumptions about product labels.
Cardarine is a common name for GW501516, also GW-1516, a synthetic compound developed as a peroxisome proliferator-activated receptor delta (PPARδ) agonist. It belongs to a class of agents that modulate gene transcription related to lipid and energy metabolism. The compound was studied in preclinical and early clinical research for metabolic and cardiovascular conditions, but it did not progress to approved therapeutic use. Its name appears in fitness and sports contexts despite not being approved as a drug.
| 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 |
Published literature on cardarine includes in vitro assays, rodent experiments, and a small number of human studies. Reports describe effects on exercise capacity and lipid metabolism in animals, while human evidence is sparse. Many online descriptions present the compound as a proven endurance aid, a claim not supported by regulatory approval or large clinical trials. Analytical studies focus on identifying the parent compound and its metabolites in biological samples. Important uncertainties include species differences, dose-response relationships, and the relevance of rodent tumor findings to humans.
Cardarine is the common name for GW501516, a synthetic compound studied as a peroxisome proliferator-activated receptor delta agonist. Researchers developed it to explore treatments for lipid disorders and metabolic conditions. It is not an approved medicine in any country. Early clinical work examined changes in HDL cholesterol and triglycerides, but development was discontinued after animal studies raised concerns about cancer. The compound remains available as a research chemical and appears in discussions of performance enhancement.
At the molecular level, GW501516 binds and activates PPARδ, a nuclear receptor that regulates transcription. Activation shifts expression of genes involved in fatty acid oxidation, energy expenditure, and lipid transport in skeletal muscle and liver. Animal studies report increased endurance and altered lipid profiles after exposure. Human data are limited to small trials and do not establish long-term safety or efficacy. PPARδ also has roles in cell proliferation, so the relationship between activation and cancer risk remains an open question.
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.
Thiafentanil (A-3080, Thianil) is a highly potent opioid analgesic that is an analog of fentanyl, and was invented in 1986. Its analgesic potency is slightly less than that of carfentanil (itself approximately 10,000 times the potency of morphine, or 4,000 times that of heroin), though with a faster onset of effects, shorter duration of action and a slightly lesser tendency to produce respiratory depression. It is used in veterinary medicine to anesthetise animals such as impala, usually in combination with other anesthetics such as ketamine, xylazine or medetomidine to reduce the prevalence of side effects such as muscle rigidity.
== Clinical significance == There are two congenital disorders of the long bones. In a disorder known as rachitis fetalis anularis the ends of the long bones (epiphyses) are enlarged. Another disorder, rachitis fetalis micromelica, is a deficiency in the growth (as a shortness) of the bones. There is a surgical procedure called distraction osteogenesis which is used to lengthen long bones.
== History == While the use of PEDs has expanded in recent times, the practice of using substances to improve performance has been around since the Ancient Olympic Games. In the Olympic Games of 668 BC, Charmis had consumed a diet consisting of dried figs which was thought, at the time, to be a significant factor in winning the 200-yard stade race. Ancient Greek athletes at the time also incorporated substances such as wine and brandy into their training routines. Stimulants derived from plants (e.g., Cola nitida, Bufotenin, etc.) were used by the Roman gladiators to overcome injuries and fatigue. In the late 19th century as modern medicine and pharmacology were developing, PEDs saw an increase in use. Supplements were now exclusively being used to enhance muscular work capacity. The main substances being used included alcoholic drinks, caffeine, and mixtures created by the athletic trainers (e.g., strychnine tablets made of cocaine and brandy). In the 20th century, testosterone was isolated and characterized by scientists. In 1941, the first record of synthesized testosterone use occurred when a horse was given testosterone which successfully improved its race performance. Sports trainers soon after began advocating for testosterone use. Images of bodybuilders with massive muscles began circulating which further perpetuated a desire among athletes to use testosterone. In 1967, the first prohibited substance list and anti-doping measures were implemented at the 1968 Olympics. In the 1980s, the main PEDs were cortisone and anabolic steroids.
33,000, 25 October 2017 - The SENSEX closed at 33,042.50, for its first close above the 33,000 level. 34,000, 26 December 2017 - The SENSEX closed at 34,010.62, for its first close above the 34,000 level. 35,000, 17 January 2018 - The SENSEX closed at 35,081.82, for its first close above the 35,000 level. 36,000, 23 January 2018 - The SENSEX closed at 36,139.98, for its first close above the 36,000 level. 37,000, 27 July 2018 - The SENSEX on 26 July 2018 crossed the 37,000 mark for the first time during intra-day trading. On 27 July 2018 the index closed above the milestone. 38,000, 9 August 2018 - For the first time SENSEX passed the score of 38,000 during intra-day trading, and then closed at 38,024.37. 39,000, 1 April 2019 – The SENSEX on 1 April 2019 crossed the 39,000 mark for the first time during intra-day trading. 2 April 2019 – The SENSEX closed at 39,056.65, for its first close above the 39,000 level. 40,000, 23 May 2019 – The SENSEX crossed "40,000.100" at 10:45 AM for the first time. (2019 Loksabha (House of the People) Election results were getting published) 41,000, 26 November 2019 – The SENSEX crossed "41,120.28" first time during intraday trading. 42,000, 16 January 2020 - The SENSEX crossed 42,000 mark with an all-time high of 42,059.45 at around 09:47 AM. 45,000, 4 December 2020 - The SENSEX crossed 45,000 mark with an all-time high of 45,033 at around 10:30 AM. 46,000, 9 December 2020 - The SENSEX crossed 46,000 mark with an all-time high of 46,017 at around 1:30 PM.
== Expression and regulation == Metallothionein gene expression is induced by a high variety of stimuli, as metal exposure, oxidative stress, glucocorticoids, vitamin D, hydric stress, fasting, exercise, etc. Beta-hydroxylbutyration of histone proteins upregulates MT2. The level of the response to these inducers depends on the MT gene. MT genes present in their promoters specific sequences for the regulation of the expression, elements as metal response elements (MRE), glucocorticoid response elements (GRE), GC-rich boxes, basal level elements (BLE), and thyroid response elements (TRE).
Sources: en.wikipedia.org
== Preparation == Several preparation methods exist. Basic versions may be prepared using chopped meat, tomato, spices, and elbow macaroni. Another basic preparation method incorporates boxed, prepared macaroni and cheese and canned chili. Some recipes incorporate all of the ingredients together, while others are prepared with the ingredients separately layered. Those that use cheese may use grated cheese atop the dish, while others mix the cheese throughout the dish. Sometimes, onions or beans are added. Some diners in St. Louis, Missouri, serve a version called "chili mac a la mode", in which the dish is served topped with fried eggs. The dish may be prepared on a range top in a skillet, in a slow cooker, or baked as a casserole. Vegetarian and vegan versions of the dish are sometimes prepared.
The IDF traces its roots to Jewish paramilitary organizations in the New Yishuv, starting with the Second Aliyah (1904 to 1914). The first such organization was Bar-Giora, founded in September 1907. Bar-Giora was transformed into Hashomer in April 1909, which operated until the British Mandate of Palestine came into being in 1920. Hashomer was an elitist organization with narrow scope, and was mainly created to protect against criminal gangs seeking to steal property. The Zion Mule Corps and the Jewish Legion, both part of the British Army of World War I, further bolstered the Yishuv with military experience and manpower, forming the basis for later paramilitary forces. After the 1920 Palestine riots against Jews in April 1920, the Yishuv leadership realised the need for a nationwide underground defense organization, and the Haganah was founded in June of the same year. The Haganah became a full-scale defense force after the 1936–1939 Arab revolt in Palestine with an organized structure, consisting of three main units—the Field Corps, Guard Corps, and the Palmach. During World War II, many Jews from the Yishuv enlisted in the British Armed Forces. Many of them served in the British Army, culminating in the formation of the Jewish Brigade. These would eventually form the backbone of the Israel Defense Forces, and provide it with its initial manpower and doctrine. Following Israel's Declaration of Independence, prime minister and defense minister David Ben-Gurion issued an order for the formation of the Israel Defense Forces on 26 May 1948.
Alpha-thalassemia is almost always inherited. It is a recessive trait - a single defective gene is insufficient to cause illness. Due to the involvement of four alpha globin genes, the inheritance pattern is complex, with varying severity depending on the number of gene mutations inherited from each parent. Normal individuals carry 4 alpha-globin genes, comprising autosomal pairs of the HBA1 and HBA2 genes. There are approximately 130 known mutations which can cause alpha thalassemia, mainly comprising deletion of part or all of a gene which then fails to produce alpha globin. If either one gene or two out of the four is faulty, the remaining genes produce sufficient alpha globin for normal life. If three genes are faulty, the sole functioning gene produces relatively small quantities of alpha globin, causing anemia and HbH disease. Four faulty genes (and therefore zero alpha globin) is incompatible with life. In rare cases alpha thalassemia can be acquired as a consequence of myelodysplastic cancer.
=== Diet === Adapting nutritional intake can help to prevent and treat overtraining. Athletes in different fields will emphasize different proportional nutrition factors on the diet mainly including proteins, carbohydrates and fats. The diet includes a calorie intake that at least matches expenditure, ideally forming a suitable macronutrient ratio. During the recovery process, extra calories from diets may help the body speed the recovery. Keeping the body nourished with a balanced diet and hydrated with an adequate supply of water are both important for a successful recovery. Finally, addressing vitamin deficiencies with improved diet and/or nutritional supplements has been proposed as a way to speed up recovery.
1993/2589) Mental Health Services of Salford National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2590) Hartlepool Community Care National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2591) Blackburn, Hyndburn and Ribble Valley Health Care National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2592) Northumberland Community Health National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2593) North Manchester Healthcare National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2594) Community Healthcare Bolton National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2595) CommuniCare National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2596) Blackpool, Wyre and Fylde Community Health Services National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2597) Blackpool Victoria Hospital National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2598) Bury Health Care National Health Service Trust (Establishment) Order 1993 (S.I. 1993/2599)
Sources: en.wikipedia.org
Clinicians use drug detoxification to reduce or relieve withdrawal symptoms while helping an addicted person adjust to living without drug use. Drug detoxification does not aim to treat addiction but rather represents an early step within long-term treatment. Detoxification may be achieved drug-free or may use medications as an aspect of treatment. Often drug detoxification and treatment will occur in a community program that lasts several months and takes place in a residential setting rather than in a medical center. Drug detoxification varies depending on the location of treatment, but most detox centers provide treatment to avoid the symptoms of physical withdrawal from alcohol and from other drugs. Most also incorporate counseling and therapy during detox to help with the consequences of withdrawal.
The DNA nucleotides adenosine and guanosine consist of a purine base attached to a ribose sugar with a glycosidic bond. In the case of RNA nucleotides deoxyadenosine and deoxyguanosine, the purine bases are attached to a deoxyribose sugar with a glycosidic bond. The purine bases on DNA and RNA nucleotides are synthesized in a twelve-step reaction mechanism present in most single-celled organisms. Higher eukaryotes employ a similar reaction mechanism in ten reaction steps. Purine bases are synthesized by converting phosphoribosyl pyrophosphate (PRPP) to inosine monophosphate (IMP), which is the first key intermediate in purine base biosynthesis. Further enzymatic modification of IMP produces the adenosine and guanosine bases of nucleotides.
=== Dihydrolipoyl dehydrogenase Binding protein (E3BP) === An auxiliary protein unique to most eukaryotes is the E3 binding protein (E3BP), which serves to bind the E3 subunit to the PDC complex. In the case of human E3BP, hydrophobic proline and leucine residues in the BP interact with the surface recognition site formed by the binding of two identical E3 monomers.
=== Chronology of boxed warnings === In 2008, the U.S. FDA added black box warnings on all fluoroquinolones, advising of the increased risk of tendon damage. In 2016, the FDA found that systemic use (by mouth or injection) of fluoroquinolones was associated with "disabling and potentially permanent serious side effects" involving the tendons, muscles, joints, nerves, and central nervous system, concluding that these side effects generally outweigh the benefits for people with acute sinusitis, acute bronchitis, and uncomplicated urinary tract infections when other treatment options are available. Concerns regarding low blood sugar and mental health problems were added in 2018. In December 2018, the FDA issued a warning regarding an increased risk of aortic aneurysms and aortic dissections associated with fluoroquinolone use. This warning specifically targeted older adults and patients with conditions such as hypertension, Marfan syndrome, Ehlers–Danlos syndrome, atherosclerosis, peripheral vascular disease, and a history of aneurysms.
Bagwell disclosed that he was only in good enough condition to play every several days, rather than every day. He was eventually paid the full amount of his contract. The Astros and the insurance company settled the claim in a confidential arrangement the same day he announced his retirement. The Astros declined to pick up Bagwell's $18 million club option for 2007, instead buying it out for $7 million. He filed for free agency in November 2006 but announced his retirement one month later. Owner Drayton McLane and general manager Tim Purpura stated that he would remain in player development department of the Astros organization, as one of the assistants to the general manager.
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.
Cardarine is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.