Anti-doping raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-09-21. Anything still debated is marked as such rather than presented as settled.
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.
Early clinical research explored GW501516 for lipid disorders, obesity, and diabetes. Some short-term human studies reported changes in HDL cholesterol, LDL cholesterol, and triglycerides. The development program was discontinued after rodent studies showed dose-dependent tumor formation in multiple tissues, including liver, bladder, stomach, and skin. These findings raised concerns about long-term cancer risk in humans. Because human exposure data are limited, the clinical significance of the rodent tumors remains uncertain.
Literature on cardarine often separates receptor pharmacology from toxicology. Mechanistic papers describe PPARδ activation and gene expression changes, while safety assessments focus on carcinogenicity and species differences. Questions remain about whether rodent tumors arise through PPARδ-dependent or off-target mechanisms. Another open area is how human metabolism and exposure compare with those in animal studies. Analytical methods such as liquid chromatography–mass spectrometry are used to confirm identity in biological and product samples.
| Property | Value | Notes |
|---|---|---|
| Chemical class | PPARδ agonist | Not an anabolic steroid. |
| Common synonyms | GW501516, GW-1516 | Cardarine is an informal name. |
| Appearance | White to off-white powder | Typical for research-grade solid. |
| Solubility class | Poorly soluble in water; soluble in some organic solvents | Such as DMSO or ethanol in laboratory settings. |
| Typical storage temperature | Cool, dry, protected from light | Specific conditions vary by supplier and form. |
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.
Because cardarine is not an approved medicine, no pharmacopeial monograph defines its identity, purity, or storage requirements. Laboratories typically rely on in-house methods and reference standards when testing materials labeled as GW501516. Certificates of analysis may report purity and identity for a specific batch, but their scope varies and they do not guarantee safety or legal status. Independent verification can include high-performance liquid chromatography, mass spectrometry, nuclear magnetic resonance, and elemental analysis. The distinction between research chemical labeling and human use is significant because quality standards and oversight differ.
Cardarine can be detected in biological samples and product materials using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method separates compounds by chromatography and identifies them by mass-to-charge transitions, allowing low-level detection in urine or blood. Sample preparation often involves enzymatic hydrolysis, solid-phase extraction, or protein precipitation. Certified reference materials and isotope-labeled internal standards improve quantification. Detection windows depend on metabolism, matrix, and assay sensitivity, so no single universal window applies.
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.
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.
The recommended daily allowance (RDA) of methionine (combined with cysteine) for adults is set at 13–14 mg kg-1 day-1 (13–14 mg per kg of body weight per day), but some researchers have argued that this figure is too low, and should more appropriately be 25 mg kg-1 day-1. Despite the importance of sulfur, restrictions of dietary sulfur are sometimes recommended for certain diseases and for other reasons.
The United States of America stayed neutral, but some Americans were eager to participate. Early in the war Lord Roberts cabled Major Frederick Russell Burnham, a veteran of both Matabele wars but then prospecting in the Klondike, to serve on his personal staff as Chief of Scouts. Burnham went on to receive the highest awards of any American who served in the war. American mercenaries participated on both sides. Portugal had considerable dealings with the South African Republic through Portuguese Mozambique. The war broke out while Portugal was engaged in its own pacification campaigns in Africa and after the 1890 British Ultimatum Portuguese public opinion was highly favourable to the Boers, but the Portuguese government chose not to hostilize the United Kingdom. Instead it took the opportunity to mend bilateral relations and reaffirm the Anglo-Portuguese alliance through the signing of the Second Treaty of Windsor, by which Britain recognized Portuguese claims in Africa and reaffirmed its pledge to help defend Portugal as well as its overseas empire against all enemies "future and present", in exchange for Portugal not declaring neutrality and providing aid against the Boers, namely by blocking the passage of weapons and ammunitions through its territory and allowing Britain the use of its port facilities. In 1900, 700 Boers crossed into Mozambique to seek refuge, but this group soon grew to 1400-2500. 700-900 were transported to Caldas da Rainha in Portugal, where they were kept until the end of the war.
== External links == Intrinsically disordered protein at Proteopedia MobiDB: a comprehensive database of intrinsic protein disorder annotations IDEAL - Intrinsically Disordered proteins with Extensive Annotations and Literature Archived 2020-05-02 at the Wayback Machine D2P2 Database of Disordered Protein Predictions Gallery of images of intrinsically disordered proteins First IDP journal covering all topics of IDP research IDP Journal Database of experimentally validated IDPs IDP ensemble database Archived 2018-03-10 at the Wayback Machine
== Calcium-deficient hydroxyapatite == Calcium-deficient (non-stoichiometric) hydroxyapatite, Ca10−x(PO4)6−x(HPO4)x(OH)2−x (where x is between 0 and 1) has a Ca/P ratio between 1.67 and 1.5. The Ca/P ratio is often used in the discussion of calcium phosphate phases. Stoichiometric apatite Ca10(PO4)6(OH)2 has a Ca/P ratio of 10:6 normally expressed as 1.67. The non-stoichiometric phases have the hydroxyapatite structure with cation vacancies (Ca2+) and anion (OH−) vacancies. The sites occupied solely by phosphate anions in stoichiometric hydroxyapatite, are occupied by phosphate or hydrogen phosphate, HPO2−4, anions. These calcium-deficient phases can be prepared by precipitation from a mixture of calcium nitrate and diammonium phosphate with the desired Ca/P ratio, for example, to make a sample with a Ca/P ratio of 1.6:
Sources: en.wikipedia.org
== Biological activity == L-Proline has been found to act as a weak agonist of the glycine receptor and of both NMDA and non-NMDA (AMPA/kainate) ionotropic glutamate receptors. It has been proposed to be a potential endogenous excitotoxin. In plants, proline accumulation is a common physiological response to various stresses but is also part of the developmental program in generative tissues (e.g. pollen). EPRS1 charges with proline to transfer it to tRNA, which can incorporate it into newly synthesized peptide chain during protein translation.
Antagonism of the α1-adrenergic receptor is thought to cause orthostatic hypotension and dizziness. Inhibition of muscarinic acetylcholine receptors is responsible for the anticholinergic side effects of clomipramine like dry mouth, constipation, urinary retention, blurred vision, and cognitive/memory impairment. In overdose, sodium channel blockade in the brain is believed to cause the coma and seizures associated with TCAs while blockade of sodium channels in the heart is considered to cause cardiac arrhythmias, cardiac arrest, and death. On the other hand, sodium channel blockade is also thought to contribute to the analgesic effects of TCAs, for instance in the treatment of neuropathic pain. The exceptionally strong serotonin reuptake inhibition of clomipramine likely precludes the possibility of its antagonism of serotonin receptors (which it binds to with more than 100-fold lower affinity than the SERT) resulting in a net decrease in signaling by these receptors. In accordance, while serotonin receptor antagonists like cyproheptadine and chlorpromazine are effective as antidotes against serotonin syndrome, clomipramine is nonetheless capable of inducing this syndrome. In fact, while all TCAs are SRIs and serotonin receptor antagonists to varying extents, the only TCAs that are associated with serotonin syndrome are clomipramine and to a lesser extent its dechlorinated analogue imipramine, which are the two most potent SRIs of the TCAs (and in relation to this have the highest ratios of serotonin reuptake inhibition to serotonin receptor antagonism).
== Pharmacokinetics == Tigecycline is metabolized through glucuronidation into glucuronide conjugates and a N-acetyl-9-aminominocycline metabolite. Therefore, dose adjustments are needed for patients with severe hepatic impairment. More so, it is primarily eliminated unchanged in the feces and secondarily eliminated by the kidneys. No renal adjustments are necessary.
Sulfuric acid is a key substance in the chemical industry. It is most commonly used in fertilizer manufacture, but is also important in mineral processing, oil refining, wastewater treating, and chemical synthesis. It has a wide range of applications, including in domestic acidic drain cleaners, as an electrolyte in lead-acid batteries, as a dehydrating compound, and in various cleaning agents.
The International Rice Research Institute and the International Maize and Wheat Improvement Center are part of a consortium of agricultural research organizations known as CGIAR. Costing around $600 million, over 50 years, the revolution brought new farming technology, increased productivity, expanded crop yields and mass fertilization to many countries throughout the world. Later it funded over $100 million of plant biotechnology research and trained over four hundred scientists from Asia, Africa and Latin America. It also invested in the production of transgenic crops, including rice and maize. In 1999, the then president Gordon Conway addressed the Monsanto Company board of directors, warning of the possible social and environmental dangers of this biotechnology, and requesting them to disavow the use of so-called terminator genes; the company later complied. In the 1990s, the foundation shifted its agriculture work and emphasis to Africa; in 2006, it joined with the Bill & Melinda Gates Foundation in a $150 million effort to fight hunger in the continent through improved agricultural productivity. In an interview marking the 100 year anniversary of the Rockefeller Foundation, Judith Rodin explained to This Is Africa that Rockefeller has been involved in Africa since their beginning in three main areas – health, agriculture and education, though agriculture has been and continues to be their largest investment in Africa.
Sources: en.wikipedia.org
=== 1960s === 1960: Rosalyn Yalow received the Nobel Prize in Physiology or Medicine "for the development of radioimmunoassays of peptide hormones" along with Roger Guillemin and Andrew V. Schally who received it "for their discoveries concerning the peptide hormone production of the brain". 1962: Katherine Johnson performed the calculations for the NASA orbital mission, launching John Glenn as the first person into orbit and returning them safely. 1963: Maria Goeppert Mayer became the first American woman to receive a Nobel Prize in Physics; she shared the prize with J. Hans D. Jensen "for their discoveries concerning nuclear shell structure” and Eugene Paul Wigner "for his contributions to the theory of the atomic nucleus and the elementary particles, particularly through the discovery and application of fundamental symmetry principles". She was born in Poland, but became a U.S. citizen in 1933. 1965: Sister Mary Kenneth Keller became the first American woman to earn a Ph.D. in Computer Science. Her thesis was titled "Inductive Inference on Computer Generated Patterns."
Periplaneta lateralis (also Shelfordella lateralis, Blatta lateralis), commonly known as the Turkestan cockroach, red runner cockroach, or rusty red cockroach, is a primarily outdoor-dwelling cockroach native to an area stretching from northern Africa to Central Asia.
== Further reading == Fischer, H.; Esbjornsson, M.; Sabina, R. L.; Stromberg, A.; Peyrard-Janvid, M.; Norman, B. (2007). "AMP deaminase deficiency is associated with lower sprint cycling performance in healthy subjects". Journal of Applied Physiology. 103 (1): 315–22. doi:10.1152/japplphysiol.00185.2007. PMID 17463303. Skalova, K; Luptak, I; Turcani, M; Hulin, I (2002). "Adenosine and cardioprotection: what can we learn from nature's genetic polymorphism?" (PDF). Bratislavske Lekarske Listy. 103 (6): 187–93. PMID 12448564. Archived from the original (PDF) on 2012-03-23. Retrieved 2011-08-12.
In implementing the regulatory changes, Federal Reserve Vice Chair Randal Quarles also changed the Federal Reserve's bank supervisory culture, allegedly making routine supervision less intense and more predictable.
=== Size and length === There is no identified correlation between the size of the glans or clitoris as a whole, and a woman's age, height, weight, use of hormonal contraception, or being postmenopausal, although women who have given birth may have significantly larger clitoral measurements. Centimetre and millimetre measurements of the clitoris show variations in size. The clitoral glans has been cited as typically varying from 2 mm to 1 cm (less than an inch) and usually being estimated at 4 to 5 mm in both the transverse and longitudinal planes. A 1992 study concluded that the total clitoral length, including glans and body, is 16.0 ± 4.3 mm (0.63 ± 0.17 in), where 16 mm (0.63 in) is the mean and 4.3 mm (0.17 in) is the standard deviation. Concerning other studies, researchers from the Elizabeth Garrett Anderson and Obstetric Hospital in London measured the labia and other genital structures of 50 women from the age of 18 to 50, with a mean age of 35.6., from 2003 to 2004, and the results given for the clitoral glans were 3–10 mm for the range and 5.5 [1.7] mm for the mean. Other research indicates that the clitoral body can measure 5–7 centimetres (2.0–2.8 in) in length, while the clitoral body and crura together can be 10 centimetres (3.9 in) or more in length.
Sources: en.wikipedia.org
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.
No, cardarine is not a steroid. It is classified as a PPARδ agonist. Its structure and receptor target differ from anabolic steroids.
No regulatory agency has approved cardarine as a medicine. It was investigated in early research but development was discontinued. It is not available as a prescription drug.
It targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not act primarily on androgen receptors. This distinction separates it from SARMs.