If you have been reading about LC-MS/MS and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-09-25. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Sporting authorities added GW501516 to prohibited lists after it appeared in athlete samples and online markets. The World Anti-Doping Agency classifies it as a hormone and metabolic modulator, and its use can lead to an anti-doping rule violation. Some early laboratory work suggested effects on fatty acid oxidation and endurance-related metabolism in animals, but those findings do not establish safe or effective use in people. Reports of adverse events in humans are scarce and often anecdotal, which complicates risk assessment.
Legal status varies by country. In some places, cardarine is controlled under medicines or psychoactive substances laws; in others, it may be sold with minimal oversight as a research chemical. Customs agencies have intercepted shipments, and several national health agencies have issued warnings about products marketed for bodybuilding or performance enhancement. The lack of a standardized pharmaceutical supply means identity, purity, and contamination levels can differ widely between samples. These factors make cardarine a regulatory and public health concern rather than a conventional prescription drug.
| Property | Value | Notes |
|---|---|---|
| Common name | Cardarine | Also called GW501516 and endurobol. |
| Chemical formula | C21H18F3NO3S2 | Molecular weight about 453.5 g/mol. |
| Appearance | White to off-white solid | Form depends on synthesis and purity. |
| Solubility | Soluble in DMSO and ethanol | Low solubility in water. |
| Typical storage | -20 °C, desiccated, protected from light | Common for research chemicals. |
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.
Regulatory treatment of cardarine differs by context and jurisdiction. In competitive sport, the World Anti-Doping Agency lists PPARδ agonists, including GW501516, as prohibited at all times. Outside sport, it lacks approval as a prescription medicine in major drug markets, and products sold for human consumption may be treated as unapproved drugs. Some countries also restrict importation or sale through general consumer protection and medicines laws. These classifications affect availability, testing, and legal risk without establishing therapeutic value.
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.
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.
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.
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.
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.
===== Type 2B ===== This is a "gain of function" defect. The ability of the qualitatively defective VWF to bind to glycoprotein Ib (GPIb) receptor on the platelet membrane is abnormally enhanced, leading to its spontaneous binding to platelets and subsequent rapid clearance of the bound platelets and of the large VWF multimers. Thrombocytopenia may occur. Large VWF multimers are reduced or absent from the circulation. The ristocetin cofactor activity is low when the patient's platelet-poor plasma is assayed against formalin-fixed, normal donor platelets. However, when the assay is performed with the patient's own platelets (platelet-rich plasma), a lower-than-normal amount of ristocetin causes aggregation to occur. This is due to the large VWF multimers remaining bound to the patient's platelets. Patients with this subtype are unable to use desmopressin as a treatment for bleeding, because it can lead to unwanted platelet aggregation and aggravation of thrombocytopenia.
Around the elements in the middle of the periodic table, isotopes that are lighter than stable isotopes of the same element tend to decay through electron capture, while isotopes heavier than the stable ones decay by electron emission. Electron capture happens most often in the heavier neutron-deficient elements where the mass change is smallest and positron emission is not always possible. When the loss of mass in a nuclear reaction is greater than zero but less than 2mec2 the process cannot occur by positron emission, but occurs spontaneously for electron capture.
Although the error rate for both whites and blacks was calibrated equal at exactly 61%, the errors for each race were different—the system consistently overestimated the chance that a black person would re-offend and would underestimate the chance that a white person would not re-offend. In 2017, several researchers showed that it was mathematically impossible for COMPAS to accommodate all possible measures of fairness when the base rates of re-offence were different for whites and blacks in the data. A program can make biased decisions even if the data does not explicitly mention a problematic feature (such as "race" or "gender"). The feature will correlate with other features (like "address", "shopping history" or "first name"), and the program will make the same decisions based on these features as it would on "race" or "gender". Moritz Hardt said "the most robust fact in this research area is that fairness through blindness doesn't work." Criticism of COMPAS highlighted that machine learning models are designed to make "predictions" that are only valid if we assume that the future will resemble the past. If they are trained on data that includes the results of racist decisions in the past, machine learning models must predict that racist decisions will be made in the future. If an application then uses these predictions as recommendations, some of these "recommendations" will likely be racist. Thus, machine learning is not well suited to help make decisions in areas where there is hope that the future will be better than the past.
(2026) identify diagnostic Tasmanian devil specimens from the Juukan 2 Rock Shelter (Pilbara, Western Australia), providing direct evidence of presence of the species in the northwestern Australian mainland during the Late Pleistocene and Holocene, and study chewed and digested bones from the same site accumulated through human activity, interpreted as likely evidence of subsistence of the Tasmanian devils off human activity at the studied site. Watts et al. (2026) study the hindlimb morphology of Hadronomas puckridgi, and interpret its foot with a robust fifth digit as representing an intermediate stage in sthenurine evolution, preceding the appearance of astragalar specializations and loss of the fifth digit in later sthenurines. Evidence from the study of extant and extinct kangaroos, indicating that giant extinct kangaroos were mechanically capable of hopping but it may not have been their primary locomotor mode, is presented by Jones, Jones & Nudds (2026). Couzens, King & Prideaux (2026) report evidence from the study of the fossil record of kangaroos indicative of a progressive increase in tooth enamel thickness in grass-feeding taxa that coincided with expansion of arid habitats in Australia since the late Miocene. Koungoulos, Kerr & O'Connor (2026) describe a manual phalanx bone of a member of the genus Protemnodon from the Taora rockshelter (Papua New Guinea), providing evidence of local survival of members of this genus into the middle Holocene.
Sources: en.wikipedia.org
=== Disclosure of the identity of BasedBeffJezos === Forbes disclosed in December 2023 that the @BasedBeffJezos persona is maintained by Guillaume Verdon, a Canadian former Google quantum computing engineer and theoretical physicist. The revelation was supported by a voice analysis conducted by the National Center for Media Forensics of the University of Colorado Denver, which further confirmed the match between Jezos and Verdon. The magazine justified its decision to disclose Verdon's identity on the grounds of it being "in the public interest". On 29 December 2023 Guillaume Verdon was interviewed by Lex Fridman on the Lex Fridman Podcast and introduced as the "creator of the effective accelerationism movement".
== Founding of Novo Terapeutisk Laboratorium == In 1924 a dispute occurred at Nordisk: Thorvald was fired by Hans Christian Hagedorn, co-founder of Nordisk, and Harald resigned in solidarity. In February 1925 the brothers formally founded Novo Terapeutisk Laboratorium. The company developed a dedicated insulin production facility and a specialty injection device (the "Novo Syringe").
== Pollution tolerance == Xanthoria parietina is highly resistant to air pollution, including heavy metals, nitrogen compounds, and ozone. Laboratory experiments have shown that it tolerates exposure to air contaminants and bisulfite ions with little or no damage. It is also resistant to heavy metal contamination and nitrogen pollution. The mechanisms underlying this tolerance involve multiple protective systems. The parietin layer in the upper cortex acts as a hydrophobic barrier, reducing the penetration of toxic metal ions into the photobiont cells. Experimental studies have shown that parietin-deficient thalli experience greater physiological stress when exposed to heavy metals. Parietin also contributes to ozone tolerance; fumigation experiments revealed that samples containing parietin recovered photosynthetic efficiency and chlorophyll integrity more quickly than those without it, suggesting an antioxidant function in addition to its role as a light-screening pigment. Furthermore, reactive oxygen species (ROS) levels induced by ozone exposure were significantly higher in parietin-deficient samples, reinforcing its role in oxidative stress mitigation. The hydration state of X. parietina influences its ozone sensitivity. Dry thalli suffer less damage and recover more quickly than hydrated ones, likely because reduced gas exchange limits ozone penetration. This factor helps explain the lichen's resilience in Mediterranean climates, where it often remains desiccated during periods of high ozone pollution.
Sources: en.wikipedia.org
Cardarine is a common name for the investigational compound GW501516. It acts as a PPARδ agonist and is not approved for human use. It is prohibited in sport.
It activates PPARδ, a nuclear receptor that influences gene expression related to lipid and energy metabolism. Animal studies show changes in endurance and lipid levels. Human effects and risks are not well established.
No, cardarine is not a steroid. It belongs to a different chemical class, the PPARδ agonists. It is also not a selective androgen receptor modulator.
No. Major drug regulators have not approved GW501516 for treating any medical condition. Products sold as cardarine are typically unapproved research chemicals or supplements, so their contents and safety are not assured.