A practical reference on LC-MS/MS: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-06-10 and is reviewed periodically as new material appears.
Anti-doping laboratories identify GW501516 and related metabolites using liquid chromatography coupled with tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be analyzed. The method targets the parent compound and phase I and phase II metabolites, which extend the detection window. Because the substance is prohibited at all times, athletes can be tested outside competition. Detection limits and windows depend on the assay, sample type, and individual metabolism.
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
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.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport; not approved as medicine | Listed by WADA at all times. |
| Common synonyms | GW501516, GW-501516, endurobol | Cardarine is a colloquial name. |
| Typical analytical method | LC-MS/MS | Detects parent compound and metabolites. |
| Common test matrix | Urine | Blood and dried blood spots also possible. |
| Legal classification | Varies by country | Often treated as unapproved drug or research chemical. |
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.
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.
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.
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.
Cardarine is prohibited in competitive sport under the World Anti-Doping Agency code, where it is classified as a metabolic modulator. It is not approved as a prescription medicine in the United States, European Union, or other major markets. Regulatory action has focused on its presence in sports and in products marketed as research chemicals. Because it has no accepted medical indication, supply is often unregulated. This status creates legal and safety uncertainties for anyone who encounters the substance.
== Signs and symptoms == The various types of VWD present with varying degrees of bleeding tendency, usually in the form of easy bruising, nosebleeds, and bleeding gums. Women may experience heavy menstrual periods and blood loss during childbirth. Symptoms of VWD vary depending on age, sex, and VWD type. In children, bruising and nosebleeds are common symptoms. In adults, easy bruising, heavy menstrual bleeding, and bleeding from minor wounds are more common. Sixty to eighty percent of people with VWD have excessive bleeding after surgery or dental extractions. Gastrointestinal bleeding from dilated blood vessels lining the gut (angiodysplasia) can result in severe, lifethreatening gastrointestinal bleeding. This most commonly occurs in seniors with type 2 or 3 VWD. Von Willebrand factor levels normally increase with age, so disease severity often decreases with older age. In women with VWD, 80% have heavy menstrual bleeding with 20% requiring removal of the uterus (hysterectomy). Due to its association with heavy menstrual bleeding, VWD is more commonly diagnosed in women. Women with VWD may also experience heavy bleeding after delivery (postpartum bleeding). Severe internal bleeding and bleeding into joints are rare in those with VWD, but they are more common in those with the more severe type 3 disease. Bleeding in the brain or spinal cord is exceedingly rare in all 3 types of VWD.
Resistance to lidocaine and bupivacaine is not uncommon, and mepivacaine tends to work better in people with EDS. Special recommendations for anesthesia are given for people with EDS. Detailed recommendations for anesthesia and perioperative care of people with EDS should be used to improve safety. Surgery in people with EDS requires careful tissue handling and a longer immobilization afterward.
== Associated disorders == Defects in Collagen VI are associated with Ullrich congenital muscular dystrophy and Bethlem myopathy. Phenotypes associated with Ullrich congenital muscular dystrophy are typically more severe than phenotypes associated with Bethlem myopathy. Rare cases of collagen VI related myopathies with phenotypes of intermediate severity have been reported. Whole genome sequencing reveals that these intermediate phenotypes most likely result from a premature translation termination codon caused by a variation in the COL6A3 gene, as well as an amino acid substitution in the N2-terminal domain caused by nonsense-mediated decay. Biopsied muscle tissue samples in individuals with Ullrich congenital muscular dystrophy and Bethlem myopathy showed a significant decrease in protein levels of Beclin1 and VNIP3, demonstrating that mutated ColVI causes defect in the regulation of autophagic pathways. In the absence of any proven therapeutic agents for treatment, a global registry is intended to facilitate matching people living with the conditions with potential clinical trials. At present the primary methods of treating these disorders are surgery and physical therapy.
==== Myofibroblast ==== Mammalian wounds that involve the dermis of the skin heal by repair, not regeneration (except in 1st trimester inter-uterine wounds and in the regeneration of deer antlers). Full-thickness wounds heal by a combination of wound contracture and edge re-epitheliasation. Partial thickness wounds heal by edge re-epithelialisation and epidermal migration from adnexal structures (hair follicles, sweat glands and sebaceous glands). The site of keratinocyte stem cells remains unknown but stem cells are likely to reside in the basal layer of the epidermis and below the bulge area of hair follicles. The fibroblast involved in scarring and contraction is the myofibroblast, which is a specialized contractile fibroblast. These cells express α-smooth muscle actin (α-SMA). The myofibroblasts are absent in the first trimester in the embryonic stage where damage heals scar-free; in small incisional or excision wounds less than 2 mm that also heal without scarring; and in adult unwounded tissues where the fibroblast in itself is arrested; however, the myofibroblast is found in massive numbers in adult wound healing which heals with a scar. The myofibroblasts make up a high proportion of the fibroblasts proliferating in the postembryonic wound at the onset of healing. In the rat model, for instance, myofibroblasts can constitute up to 70% of the fibroblasts, and is responsible for fibrosis on tissue. Generally, the myofibroblasts disappear from the wound within 30 days, but can remain in pathological cases in hypertrophy, such as keloids.
== Properties == All elements with atomic number greater than 94 decay quickly enough into lighter elements such that any atoms of these that may have existed when the Earth formed (about 4.6 billion years ago) have long since decayed. Synthetic elements now present on Earth are the product of atomic bombs or experiments that involve nuclear reactors or particle accelerators, via nuclear fusion or neutron absorption. Atomic mass for natural elements is based on weighted average abundance of natural isotopes in Earth's crust and atmosphere. For synthetic elements, there is no "natural isotope abundance". Therefore, for synthetic elements the total nucleon count (protons plus neutrons) of the most stable isotope, i.e., the isotope with the longest half-life—is listed in brackets as the atomic mass.
Sources: en.wikipedia.org
=== Social control and conformity === The concept of "mental illness" is often used to label and control those with beliefs and behaviours that the majority of people disagree with. The basic premise of the anti-psychiatry movement is that psychiatrists attempt to classify "normal" people as "deviant", psychiatric treatments are ultimately more damaging than helpful to patients; psychiatry's history involves discredited treatments, such as psychosurgery, an example of this being the frontal lobectomy (commonly called a lobotomy). The use of lobotomies largely disappeared by the late 1970s. On Michel Foucault's Madness and Civilization, Sapouna (2001) writes, "[his book provides] a framework to conceptualize confinement as a process of exclusion and 'silencing of the mad'."
== Legacy == The name continues in use as a geographical and cultural term, and it survives in Cumberland sausages; HMS Cumberland; the Cumberland Fell Runners Club; the Cumberland Athletics Club; and various organisations and companies, such as the local newspapers The Cumberland News, and The West Cumberland Times and Star, and the Cumberland Building Society. It is also mentioned in Macbeth as the kingdom given to Prince Malcolm, and is also the initial setting for the Geoffrey Trease historical novel Cue for Treason. In June 1994, during the 1990s UK local government reform, the Local Government Commission published draft recommendations, suggesting as one option a North Cumbria unitary authority (also including Appleby, the historic county town of Westmorland). It also suggested that Cumberland could be reinstated as an independent ceremonial county. The final recommendations, published in October 1994, did not include such recommendations, apparently due to lack of expression of support for the proposal to the commission. The Grass-of-Parnassus was the county flower. It had been associated with the county since 1951, when it was included in the coat of arms granted to the Cumberland County Council. It subsequently featured in the arms granted to Cumbria County Council and Copeland Borough Council, in both cases to represent Cumberland. The flower was also attributed to Cumbria in 2002 as part of a national County flowers of the United Kingdom campaign by the charity Plantlife.
=== Nutrition === In nature, mice are usually herbivores, consuming a wide range of fruit or grain. However, in laboratory studies it is usually necessary to avoid biological variation and to achieve this, laboratory mice are almost always fed only commercial pelleted mouse feed. Food intake is approximately 15 g (0.53 oz) per 100 g (3.5 oz) of body weight per day; water intake is approximately 15 ml (0.53 imp fl oz; 0.51 US fl oz) per 100 g of body weight per day.
Other major football, ice hockey, and basketball teams are based in Moscow. Because sports organizations in the Soviet Union were once centralized, two of the best Union-level teams represented defense and law-enforcement agencies: the Armed Forces (CSKA) and the Ministry of Internal Affairs (Dinamo). Most major cities had army and police sports teams. As a result, Spartak, CSKA, and Dinamo were among the best-funded teams in the USSR. The Irina Viner-Usmanova Gymnastics Palace is located in the Luzhniki Olympic Complex. Construction of the Palace started in 2017, and the opening ceremony took place on 18 June 2019. The Palace was financed by billionaire Alisher Usmanov, husband of the former gymnast and gymnastics coach Irina Viner-Usmanova. The total area of the building is 23,500 square meters (253,000 sq ft), which includes three fitness rooms, locker rooms, rooms for referees and coaches, saunas, a canteen, a cafeteria, two ball halls, a medical center, a hall for journalists, and a hotel for athletes. Because of Moscow's cold climate, winter sports are popular. Many of Moscow's parks offer marked trails for skiing and frozen ponds for skating.
Sources: en.wikipedia.org
=== South Asia === In South Asia, the color of one's skin determined social status as it implied the circumstances of one's positionality. While pale skin suggested being away from the sun, darker skin signified the result of working in external conditions. With colonial influence from Britain's occupation, there was a distinction in superiority and inferiority. With those in power attributing pale complexions, there was an association tied among class and position. The South Asian film industry was a contributing factor from colonialism in the reinforcement of these narratives. Turmeric was a used ingredient in lightening skin tone complexion to be seen as desirable.
=== Aortic regurgitation === Aortic regurgitation is treated with aortic valve replacement, which is recommended in patients with symptomatic severe aortic regurgitation. Aortic valve replacement is also recommended in patients that are asymptomatic but have chronic severe aortic regurgitation and left ventricular ejection fraction of less than 50%. Hypertension is treated in patients with chronic aortic regurgitation, with the anti-hypersensives of choice being calcium channel blockers, ACE inhibitors, or ARBs. Also, endocarditis prophylaxis is indicated before dental, gastrointestinal or genitourinary procedures. Mild to moderate aortic regurgitation should be followed with echocardiography and a cardiac stress test once every 1–2 years. In severe moderate/severe cases, patients should be followed with echocardiography and cardiac stress test and/or isotope perfusion imaging every 3–6 months.
Conversion of a cysteine residue into alanine in the presence of TCEP and heat (90˚C). Slow (but significant, 40% cleavage reported for two week storage at 4˚C) protein backbone cleavage at cysteine residues under mild conditions.
Sources: en.wikipedia.org
Legal status varies by country. It is not approved as a medicine, and it is prohibited in sport. Some jurisdictions restrict import, sale, or possession.
Laboratories use liquid chromatography-tandem mass spectrometry to detect GW501516 and its metabolites. Urine is commonly tested, and testing can occur in and out of competition.
No, cardarine is not a SARM. It is a PPARδ agonist, which acts on a different receptor. The two classes are often confused in online discussions.
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.