Cardarine 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.
Last reviewed on 2026-03-29. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Visual description for typical solid reference material. |
| Solubility | Poorly soluble in water; soluble in DMSO | Solubility depends on solvent, purity, and form. |
| Storage | Cool, dry, protected from light | Long-term storage often uses low temperature and desiccant. |
| Common analytical method | LC-MS/MS | Used for detection and quantification in biological matrices. |
| Common synonyms | GW-501516; GW501516; endurobol | Naming varies among literature, vendors, and databases. |
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.
PPARδ is a nuclear receptor that influences transcription of genes involved in fatty acid oxidation, lipid transport, and energy homeostasis. GW501516 binds and activates this receptor with high selectivity relative to PPARα and PPARγ in laboratory assays. Activation alters expression of target genes in skeletal muscle, liver, and adipose tissue in animal models. The exact clinical consequences of these changes in humans remain incompletely characterized, and observed effects in animals do not establish therapeutic benefit or safety.
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.
=== Rotigotine === Rotigotine (sold under the brand name Neupro, among others) is a dopamine agonist indicated for the treatment of Parkinson's disease (PD) and restless legs syndrome (RLS). In 2007, the Neupro patch was approved by the Food and Drug Administration (FDA) as the first transdermal patch treatment of Parkinson's disease in the United States. The drug had been established in 1980, and no prior polymorphism had been observed. In 2008, a more stable polymorph unexpectedly emerged, which was described as resembling "snow-like crystals". The new polymorph did not display any observable reduction in efficacy, but nonetheless, Schwarz Pharma recalled all Neupro patches in the United States and some in Europe. Those with remaining patches in Europe were told to refrigerate their stock, since refrigeration seemed to reduce crystallization rates. The patch was reformulated in 2012, as per FDA recommendations, and was reintroduced in the United States without requiring refrigeration.
=== Preclinical safety data === Conventional long-term toxicity, reproduction, mutagenicity, and carcinogenicity studies have been performed in laboratory animals. Salmon calcitonin is devoid of embryotoxic, teratogenic, and mutagenic potential. An increased incidence of pituitary adenomas has been reported in rats given synthetic salmon calcitonin for 1 year. This is considered a species-specific effect and of no clinical relevance. Salmon calcitonin does not cross the placental barrier. In lactating animals given calcitonin, suppression of milk production has been observed. Calcitonin is secreted into the milk.
== Pharmacology in pain == Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. It is an essential defensive function where pain works as an alarm to avoid or limit tissue damage. Its neurobiology is complex, and involves stimulation of several different types of nerves. Opioids act upon opioid receptors that are coupled to inhibitor G protein coupled receptors (GPCR). These receptors fall into 3 classes: μ (mu), δ (delta), and κ (kappa) receptors. More than 70% of opioid receptors are μ receptors, predominantly located on the central terminals of nociceptors in the dorsal horn of the spinal cord. The remaining 30% of opioid receptors are located post-synaptically on dendrites of second-order spinothalamic neurons & interneurons. When an opiate binds as an agonist to the GPCR, there will be a signaling cascade resulting in the inhibition of adenylate cyclase and calcium ion channels with the stimulation of potassium ion channels. The net effect of these changes is a reduced intracellular cAMP and hyperpolarization of the neuronal cell reducing neurotransmitter release. Through this pathway, when opiates bind to and activate the mu receptor, there is a decrease transmission of pain signalling. This pathway targeted for the analgesia properties that opiates are known and used for. Other clinically important roles of mu are its involvement in respiratory and cardiovascular functions, gastrointestinal peristalsis, feeding, and mood.
Biden's approval rating in January 2025 was 40%, which was low but still higher than several other presidents' final approval ratings. Gallup's averaged polls of Biden's presidency found that he was the second-least popular president in its polling history, after Trump. CNN and CBS News found Biden's final approval rating to be 37% and 36%, respectively. Polling aggregator FiveThirtyEight found that Biden had a final average approval rating of 37%.
Sources: en.wikipedia.org
== Further reading == Baena-Cagnani CE (2001). "Desloratadine activity in concurrent seasonal allergic rhinitis and asthma". Allergy. 56 Suppl 65: 21–7. doi:10.1111/j.1398-9995.2001.00001.x-i1. PMID 11243501. Devillier P, Roche N, Faisy C (2008). "Clinical pharmacokinetics and pharmacodynamics of desloratadine, fexofenadine and levocetirizine : a comparative review". Clinical Pharmacokinetics. 47 (4): 217–30. doi:10.2165/00003088-200847040-00001. PMID 18336052. Geha RS, Meltzer EO (April 2001). "Desloratadine: A new, nonsedating, oral antihistamine". The Journal of Allergy and Clinical Immunology. 107 (4): 751–62. doi:10.1067/mai.2001.114239. PMID 11295678. Henz BM (2001). "The pharmacologic profile of desloratadine: a review". Allergy. 56 Suppl 65: 7–13. doi:10.1034/j.1398-9995.2001.00101.x. PMID 11243504.
=== Patient information === Blood Transfusion Leaflets (NHS Blood and Transplant) Blood Transfusion Leaflets (Welsh Blood Service) Blood Transfusion Information (Scotland) Blood Transfusion Information (Australia) Blood Transfusion Information (American Cancer Society)
Regarding the first part of the film, Barry White of Citizen Game commented, "Considering the comparatively paltry resources [...] at [the Purchase Brothers] disposal this short still manages to be better than every video game movie currently in existence." Wagner Au of NewTeeVee contended that the first part "is one of those rare viral videos that seems destined to launch a breakout success", and added "non-gamers are likely to be impressed by its rollicking action and bravura special effects." Au believed its popularity was due, in part, to the fact that the video is adapted from Half-Life 2. Patrick Goss, writing for TechRadar, said the in-game footage from the Half-Life 2 series "blended almost seamlessly into [the] live action footage" in the film. Valve, developers of the Half-Life series, approved of the film and publicized it in an announcement on Steam, saying "we were blown away – the production quality certainly exceeds that of the usual community-made movies we see."
==== Apolipoprotein B ==== Apolipoprotein B can exist in two forms: B-100 and B-48. Apolipoprotein B-100 is present on several lipoproteins, including very low-density lipoproteins (VLDL), intermediate density lipoproteins (IDL) and low density lipoproteins (LDL), and can assemble VLDL particles in the liver. Apolipoprotein B-100 has been linked to the development of atherosclerosis. ApoB is ancestrally universal to all animals, as homologs are found in choanoflagellates. The insect homolog is called apolipophorin I/II.
== Subsets == The Russell 1000 Index can be subdivided into the mega-cap Russell Top 200 Index (with about 200 constituents) and the Russell Midcap Index (with about 800 constituents). As of April 30, 2025, the Russell Top 200 and Russell Midcap comprised about 78% and 22%, respectively, of the Russell 1000's total market cap. Other subsets of the Russell 1000 (all classified within the mega-cap segment) include:
Sources: en.wikipedia.org
Bosentan inhibits endothelin-1 by blocking its action at the ETA and ETB receptors. Ambrisentan and sitaxsentan block endothelin-1 activity by selectively blocking the ETA receptor. Prostacyclins and prostacyclin agonists also cause vasodilation and also inhibit platelet aggregation. Epoprostenol, treprostinil and iloprost act as prostacyclin I2 (PGI2) analogues by binding to and activating the prostacyclin receptor to cause vasodilation. PGI2 activates adenylate cyclase to convert adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP), cAMP inhibits proliferation of smooth muscle cells in the pulmonary artery walls, and causes relaxation of smooth muscle cells thus acting as a vasodilator. Selexipag acts as a PGI2 receptor agonist to also activate adenylate cyclase. Epoprostenol and treprostinil are given as continuous intravenous infusions. Treprostinil is also available as an inhaled form, as is iloprost. In those who have a sustained vasodilator response as determined during the right heart catheterization (approximately 10% of those with PAH are responders), long acting calcium channel blockers nifedipine, diltiazem or amlodipine are indicated. In disease that is refractory to medical therapy, an atrial septostomy may be used palliatively or as a bridge to lung transplantation.
=== Onset of symptoms and diagnostic delay === In the classic phenotype, the onset of this disease is usually noticed in childhood, but often not diagnosed until the third or fourth decade of life, frequently due to misdiagnosis and dismissal of symptoms. The median age of symptom onset is 3 years, with the median diagnostic delay being 29 years. Misdiagnosis is overwhelmingly common, with approximately 90% of patients being misdiagnosed, and approximately 62% receiving multiple misdiagnoses before a correct diagnosis. The prolonged diagnostic delay, misdiagnosis or multiple misdiagnoses, or being given inappropriate exercise advice (such as ignore pain or avoid exercise) severely impacts the quality of life (QoL), physically and mentally.
On 29 September 1923, the British government became responsible for the administration of Mandatory Palestine. Along with its longstanding control of the Persian Gulf Residency and the Aden Protectorate, and its recently acquired control of the Emirate of Transjordan and of Mandatory Iraq, the British now controlled all of the territories in the Middle East except the French Mandate for Syria and the Lebanon. In 1942, the Biltmore Program was adopted as the platform of the Zionist Organization, with an explicit call "that Palestine be established as a Jewish Commonwealth." In 1946, the Anglo-American Committee of Inquiry, also known as the Grady-Morrison Committee, noted that the demand for a Jewish State went beyond the obligations of either the Balfour Declaration or the Mandate and had been expressly disowned by the Chairman of the Jewish Agency as recently as 1932. The period of the British Mandate was characterized by a great deal of political and social unrest among the Jews, the Palestinian Arabs, and the British (for example, the 1936–1939 Arab revolt, the 1944–1948 Jewish insurgency, and the 1947–1948 civil war in Mandatory Palestine). The United Nations Partition Plan for Palestine was passed on 29 November 1947. The plan was accepted by the Jewish Agency for Palestine but was rejected by the Arab Higher Committee and by most of the Arab population. The Arab League then adopted a series of resolutions endorsing a military solution to the conflict.
The colour of a salt is often different from the colour of an aqueous solution containing the constituent ions, or the hydrated form of the same compound. The anions in compounds with bonds with the most ionic character tend to be colorless (with an absorption band in the ultraviolet part of the spectrum). In compounds with less ionic character, their color deepens through yellow, orange, red, and black (as the absorption band shifts to longer wavelengths into the visible spectrum). The absorption band of simple cations shifts toward a shorter wavelength when they are involved in more covalent interactions. This occurs during hydration of metal ions, so colorless anhydrous salts with an anion absorbing in the infrared can become colorful in solution. Salts exist in many different colors, which arise either from their constituent anions, cations or solvates. For example:
Sources: en.wikipedia.org
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.
Most methods use liquid chromatography with tandem mass spectrometry. Urine is common in anti-doping testing, and blood or plasma may be used in research.
Typical guidance is cool, dry, dark storage, often at low temperature and with desiccant. Stability data are limited, so storage conditions should be verified for each batch or supplier.
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.