Everything below concerns PPARδ. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-04-05. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Laboratory handling focuses on identity, purity, and stability. Reference standards are typically stored cold and dry, protected from light, because solutions can degrade over time. Analytical checks may use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Impurities and related substances can be separated chromatographically and compared with a known standard. Because cardarine is not an approved drug, compendial monographs are absent, and laboratories often rely on in-house methods. Reported purity varies among unregulated products and should not be assumed from a label.
GW501516 binds and activates PPARδ, a nuclear receptor that influences transcription of genes involved in fatty acid oxidation and energy use. Activation shifts some metabolic pathways in preclinical models, which is why the compound has been studied for lipid disorders and exercise-related endpoints. The exact downstream effects in humans are incompletely mapped. PPARδ is expressed in many tissues, including skeletal muscle, liver, and adipose tissue, so broad activation may have varied consequences. Researchers continue to examine how selective or partial activation might alter the balance between benefits and risks.
Published human data are sparse and mostly come from early-phase trials. Those studies examined short-term changes in lipids, glucose, and exercise capacity, but they were not large enough to establish efficacy or long-term safety. Some animal experiments reported increased running endurance, yet such findings do not prove a performance benefit in people. Anti-doping laboratories detect GW501516 and its metabolites in urine or blood using liquid chromatography-tandem mass spectrometry. Detection windows depend on dose, sample type, and individual metabolism. The method is sensitive enough to identify trace residues in tested samples.
| 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. |
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.
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.
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.
=== CO-releasing molecules (CO-RMs) === Carbon monoxide-releasing molecules are metal carbonyl complexes that are being developed as potential drugs to release CO. At low concentrations, CO functions as a vasodilatory and an anti-inflammatory agent. CO-RMs have been conceived as a pharmacological strategic approach to carry and deliver controlled amounts of CO to tissues and organs.
Less than truckload (LTL) cargo is the first category of freight shipment, representing the majority of freight shipments and the majority of business-to-business (B2B) shipments. LTL shipments are also often referred to as motor freight and the carriers involved are referred to as motor carriers. LTL shipments range from 50 to 7,000 kg (110 to 15,430 lb), being less than 2.5 to 8.5 m (8 ft 2.4 in to 27 ft 10.6 in) the majority of times. The average single piece of LTL freight is 600 kg (1,323 lb) and the size of a standard pallet. Long freight and/or large freight are subject to extreme length and cubic capacity surcharges. Trailers used in LTL can range from 28 to 53 ft (8.53 to 16.15 m). The standard for city deliveries is usually 48 ft (14.63 m). In tight and residential environments the 28 ft (8.53 m) trailer is used the most. The shipments are usually palletized, stretch [shrink]-wrapped and packaged for a mixed-freight environment. Unlike express or parcel, LTL shippers must provide their own packaging, as carriers do not provide any packaging supplies or assistance. However, circumstances may require crating or another substantial packaging.
March 4, 2009: Malaysia Malaysia has a 50% chance of slipping into the recession as growth is expected to reach just 0.5% for the year, said the executive director Datuk Mohamed Ariff Abdul Kareem of the Malaysian Institute of Economic Research.
MS may stem from immune responses to activation of receptors for T-cells and B-cells involved in an inflammatory response. These T-cells produce substances called cytokines that induce an inflammatory response in the CNS, possibly leading to development of MS, according to a theory remaining under study, as of 2024.
In these early studies, the mechanisms of these metabolic processes had not been identified and a vital force was thought to animate living tissue. In the 19th century, when studying the fermentation of sugar to alcohol by yeast, Louis Pasteur concluded that fermentation was catalyzed by substances within the yeast cells he called "ferments". He wrote that "alcoholic fermentation is an act correlated with the life and organization of the yeast cells, not with the death or putrefaction of the cells." This discovery, along with the publication by Friedrich Wöhler in 1828 of a paper on the chemical synthesis of urea, and is notable for being the first organic compound prepared from wholly inorganic precursors. Wöhler's urea synthesis showed that organic compounds could be created from inorganic precursors, disputing the vital force theory that dominated early 19th-century science. Modern analyses consider this achievement as foundational for unifying organic and inorganic chemistry. It was the discovery of enzymes at the beginning of the 20th century by Eduard Buchner that separated the study of the chemical reactions of metabolism from the biological study of cells, and marked the beginnings of biochemistry. The mass of biochemical knowledge grew rapidly throughout the early 20th century. One of the most prolific of these modern biochemists was Hans Krebs who made huge contributions to the study of metabolism. He discovered the urea cycle and later, working with Hans Kornberg, the citric acid cycle and the glyoxylate cycle.
Sources: en.wikipedia.org
Level 1: COMP (exons 10–15) and MATN3 (exon 2) Level 2: COMP (exons 8 & 9 and 16–19) Level 3: COL9A1 (exon 8), COL9A2 and COL9A3 (exon 3) All those genes are involved in the production of the extracellular matrix (ECM). The role of COMP gene remains unclear. It is a noncollagenous protein of the ECM. Mutations in this gene can cause the pseudoachondroplasia (PSACH). It should play a role in the structural integrity of cartilage by its interaction with other extracellular matrix proteins and can be part of the interaction of the chondrocytes with the matrix and it is also a potent suppressor of apoptosis in chondrocytes. Another role is maintaining a vascular smooth muscle cells contractile under physiological or pathological stimuli. Since 2003, the European Skeletal Dysplasia Network has used an online system to diagnose cases referred to the network before mutation analysis to study the mutations causing PSACH or MED. COL9A1, COL9A2, COL9A3 are genes coding for collagen type IX, that is a component of hyaline cartilage. MATN3 protein may play a role in the formation of the extracellular filamentous networks and in the development and homeostasis of cartilage and bone. In the recessive form, the DTDST gene, also known as SLC26A2, is mutated in almost 90% of the patients, causing diastrophic dysplasia. It is a sulfate transporter, transmembrane glycoprotein implicated in several chondrodysplasias. It is important for sulfation of proteoglycans and matrix organization.
==== Absorption ==== Propranolol is rapidly and completely absorbed, with peak plasma levels achieved about 2 hours (range 1–3 hours) after ingestion. Its oral bioavailability is approximately 25%. Despite complete absorption, propranolol has a variable bioavailability due to extensive first-pass metabolism. Hepatic impairment therefore increases its bioavailability. Therapeutic plasma concentrations are typically between 0.02 and 0.3 mg/L. Toxicity has been reported at concentrations of 1 mg/L and above, with coma or death associated with concentrations of 4 to 10 mg/L and above. Coadministration with food appears to enhance bioavailability but does not hasten its time to peak levels. Propranolol can be absorbed along the whole intestine with the main absorption site being the colon, which means people who have lost their colon due to surgery may absorb less propranolol. Propranolol shows marked interindividual variability in pharmacokinetics, with propranolol levels varying 20-fold in different individuals.
==== Paid leave while on Family and Medical Leave Act leave ==== The temporary tax credit for employers who give paid leave to an employee while they are on Family and Medical Leave Act leave has been made permanent. In order to qualify for the tax credit, the employer must pay the employee at least 50% of the employee's usual wages. The amount of the tax credit used to be equal to 12.5% of eligible wages paid to an eligible employee, but it now increases by 0.25% for each percentage point paid above the 50% threshold, up to a maximum credit of 25%. In order to be eligible for the tax credit, the employee must have worked at least six months for the employer, which is up from 12 months previously. Paid family and medical leave that is required under state or local law is now eligible for the tax credit, as are employer-paid amounts for qualifying paid leave insurance policies.
==== Information laundering ==== Generative AI has been noted for its use by state-sponsored propaganda campaigns in information laundering. According to a 2025 report by Graphika, generative AI is used to launder articles from Chinese state media such as China Global Television Network through various social media sites in an attempt to disguise the articles' origin.
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.
Anti-doping and clinical laboratories commonly use liquid chromatography-tandem mass spectrometry. The method can identify GW501516 and its metabolites in urine or blood. Detection depends on sample timing and the amount present.