Everything below concerns Metabolite. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-01-31. Where a claim depends on a specific study, the study is described rather than over-claimed.
In the fitness and bodybuilding literature, cardarine is frequently discussed as an endurance agent or fat-loss compound, although such claims are not supported by robust clinical evidence. Online descriptions often mix animal data, user anecdotes, and marketing language. Researchers who study PPARδ agonists distinguish between receptor activation in controlled experiments and unsupervised use of unverified products. The latter introduces unknown purity, dose, and interactions, making reported experiences difficult to interpret scientifically.
GW501516 acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in transcription of genes related to lipid handling and energy use. Activation of PPARδ can shift skeletal muscle toward greater fatty acid oxidation in animal models, which is one reason it drew interest for metabolic disease and exercise research. The exact downstream effects depend on tissue, species, dose, and duration. Human data are sparse, so many proposed benefits remain hypotheses rather than established clinical outcomes.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Solubility | Soluble in dimethyl sulfoxide and some organic solvents; practically insoluble in water | Solvent choice affects laboratory handling |
| Typical storage | -20 °C, desiccated, protected from light | Common condition for research samples |
| Analytical method | Liquid chromatography–tandem mass spectrometry (LC-MS/MS) | Used for identification and quantification in biological or product samples |
| Common synonyms | GW501516, GW-501516, GSK-516, Endurobol | Names found in research and anti-doping literature |
| Regulatory status | Unapproved therapeutic; prohibited in competitive sport | Status can vary by country and context |
Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.
Regulatory treatment varies, but cardarine is not approved as a medicine. Sports authorities list GW501516 as a prohibited substance, and it is banned at all times under the World Anti-Doping Agency code. Many countries restrict sales for human consumption, while online vendors market it as a research chemical. Such products may lack purity data, and their actual contents can differ from the label. Purchasing or possessing cardarine may carry legal consequences depending on jurisdiction. The compound is not a dietary supplement ingredient in regulated markets.
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.
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 explicitly prohibited by the World Anti-Doping Agency under the class of PPARδ agonists. Its presence in urine or blood samples can be detected using mass spectrometry-based methods, often liquid chromatography-tandem mass spectrometry. Athletes who test positive may face sanctions, including bans from competition. The compound is also regulated as a prescription-only or unapproved drug in many countries. Enforcement varies by jurisdiction, and some regions treat it as a controlled substance. Online sales may occur despite these restrictions, creating quality and legal risks.
Laboratory detection of cardarine typically involves sample preparation followed by chromatographic separation and mass spectrometric identification. Urine is the most common matrix for anti-doping tests, though blood and hair have also been explored. Methods can target the parent compound or its metabolites, depending on the expected window of detection. Reference standards are required for accurate quantification. Matrix effects and dilution can influence results, so laboratories use internal standards and validation protocols. The exact detection window varies with dose, route, and individual metabolism.
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.
Preclinical research reported that GW501516 increased running endurance in mice and improved lipid profiles in some animal species. Early human trials explored effects on high-density lipoprotein cholesterol, triglycerides, and glucose handling, but the program was discontinued. Published human data are sparse and do not establish efficacy for any condition. Studies also examined PPAR delta in cancer biology, with conflicting findings across models. The relationship between receptor activation, tissue context, and disease risk remains an active area of investigation.
=== HIV transmission and treatment === In 1981, while working at UCSF in a lab that could perform the immunologic tests needed to detect immunodeficiency in AIDS patients, Ammann observed immunodeficiency disorders in children that mirrored those of gay men who had contracted the Human Immunodeficiency Virus. Ammann's investigations into the cause of the symptoms led him to identify two new means of transmission, in utero mother to infant and blood transfusions. With the medical community wanting not to believe that AIDS could affect infants, Ammann's initial publication blood transfusion infection was rejected by prominent medical journals. This discovery changed the perception of HIV/AIDS as an epidemic solely within the gay community. In 1985, Ammann left his position at UCSF in order to work with the biotechnology firm, Genentech. There he developed clinical products focused on HIV/AIDS, and although while with Genentech a successful vaccine was not developed, the discoveries made by Ammann's research team were used by other researchers in a partially successful study performed in Thailand in 2009. In 1994, Ammann was selected to become a member of the Presidential National AIDS Task Force on Drug and Vaccine Development. Three years later, in 1996, he was recognized by POZ magazine as one of the fifty most influential AIDS researchers.
=== Economics === In the United States, the 800 mcg tablet was 6.75 times more expensive as of 2020 than the lozenge. As of 2023, the average cost for an injectable fentanyl solution (50 mcg/mL) is around US$17 for a supply of 20 milliliters, depending on the pharmacy. In a 2020 report by the Australian Institute of Criminology, a 100-microgram transdermal patch was valued from between AU$75 and AU$450 on illicit markets. Furthermore, in another 2020 study, the average price per gram of non-pharmaceutical fentanyl on various cryptomarkets was US$1,470.40 for offerings of less than five grams; the average for offers over five grams was US$139.50. In addition, on DreamMarket furanfentanyl (Fu-F), the most common analog on said market, the average price per gram was US$243.10 for retail listings and US$26.50 per gram for wholesale listings.
After the passage of the Morrill Land-Grant Act of 1862, the push for a university in Arizona grew. The Arizona Territory's "Thieving Thirteenth" Legislature approved the University of Arizona in 1885 and selected the city of Tucson to receive the appropriation to build the university. Tucson hoped to receive the appropriation for the territory's mental hospital, which carried a $100,000 allocation instead of the $25,000 allotted to the territory's only university (Arizona State University was also chartered in 1885, but it was created as Arizona's normal school, and not a university). Flooding on the Salt River delayed Tucson's legislators, and by they time they reached Prescott, back-room deals allocating the most desirable territorial institutions had been made. Tucson was largely disappointed with receiving what was viewed as an inferior prize. With no parties willing to provide land for the new institution, the citizens of Tucson prepared to return the money to the Territorial Legislature until two gamblers and a saloon keeper decided to donate 40 acres to the Board of Regents. Construction of Old Main, the first building on it, began on October 27, 1887, and classes met for the first time in 1891 with 32 students in Old Main, which is still in use today. Because there were no high schools in Arizona Territory, the university maintained separate preparatory classes for the first 23 years of operation. In 1924, during Cloyd Marvin's tenure as president, the university was recognized by the Association of American Universities.
Larger supermarkets in North America and in Europe typically sell many items among many brands, sizes and varieties. U.S. publisher Supermarket News lists the following categories, for example: Hypermarkets have a larger range of non-food categories such as clothing, electronics, household decoration and appliances.
Sources: en.wikipedia.org
===== Heart ===== In 2024, researchers were able to 3D print a human heart with a biphasic bioink containing pluripotent stem cells (PSC). The technique they proposed and tested would first print the external features of the organ before then printing the internal features such as internal vasculature inside the previously printed structure. Both sets of printing were performed by extruding the bioink filament into layered structures set in a microgel medium. This technique was called the "SPIRIT" technique and allowed for the printing of a full-sized heart at significantly faster speeds than previous methods.
Foods that contain nicotinamide include yeast, meat, milk, and green vegetables. Nicotinamide was discovered between 1935 and 1937. It is on the World Health Organization's List of Essential Medicines. Nicotinamide is available as a generic medication and over the counter. Commercially, nicotinamide is made from either nicotinic acid (niacin) or nicotinonitrile. In some countries, grains have nicotinamide added to them. Extraterrestrial nicotinamide has been found in carbonaceous chondrite meteorites.
"Impact of elevated CO2 on shellfish calcification". Geophysical Research Letters. 34 (7): L07603. Bibcode:2007GeoRL..34.7603G. doi:10.1029/2006GL028554. hdl:20.500.11755/a8941c6a-6d0b-43d5-ba0d-157a7aa05668. Gattuso, J.-P.; Hansson, L.; "Ocean acidification" (Oxford University Press) Kroeker, K.; Kordas, R.; Crim, R.; Hendriks, I.; Ramajo, L.; Singh, G.; Duarte, C.; Gattuso, J.-P. (2013). "Impacts of ocean acidification on marine organisms: quantifying sensitivities and interaction with warming". Global Change Biology. 19 (6): 1884–1896. Bibcode:2013GCBio..19.1884K. doi:10.1111/gcb.12179. PMC 3664023. PMID 23505245. Gattuso, J.-P.; Magnan, A.; Billé, R.; Cheung, W.W.L.; Howes, E.L.; Joos, F.; Allemand, D.; Bopp, L.; Cooley, S.; Eakin, C.M.; Hoegh-Guldberg, O.; Kelly, R.P.; Pörtner, H.; Rogers, A.D.; Baxte, J.M.; Laffoley, D.; Osborn, D.; Rankovic, A.; Rochette, J.; Sumaila, U. R.; Treyer, S.; Turley, C. (2015). "Contrasting futures for ocean and society from different anthropogenic CO2 emissions scenarios" (PDF). Science. 349 (6243) aac4722. doi:10.1126/science.aac4722. PMID 26138982. S2CID 206639157. Magnan, A.K.; Colombier, M.; Billé, R.; Hoegh-Guldberg, O.; Joos, F.; Pörtner, H.-O; Waisman, H.; Spencer, T.; Gattuso, J.-P. (2016). "Implications of the Paris Agreement for the ocean". Nature Climate Change. 6 (8): 732–735. Bibcode:2016NatCC...6..732M. doi:10.1038/nclimate3038. Gattuso, J.-P.; Williamson, P.; Duarte, C.; Magnan, A.K. (2021). "The potential for ocean-based climate action: negative emissions technologies and beyond". Frontiers in Climate. 2 575716.
Sources: en.wikipedia.org
== Environmental samples == A naturally occurring volatile that is sometimes found in aqueous solution is methane; water itself is semivolatile. Man-made or anthropogenic chemicals also occur in these classes. Examples of volatile anthropogenic chemicals include the refrigerants chlorofluorocarbons (CFCs) and hydrofluorocarbons (HCFCs). Semivolatile anthropogenics can exist as mixtures, such as petroleum distillates or as pure chemicals like trichloroethylene (TCE). Headspace gas chromatography offers a method for determining if there is natural biodegradation processes occurring in contaminated aquifers. For example, fuel hydrocarbons will break down into methane. Chlorinated solvents such as trichloroethylene, break down into ethene and chloride. Detecting these compounds can determine if biodegradation processes are occurring and possibly at what rate. Natural gas extracted from the earth also contains many low molecular weight hydrocarbon compounds such as methane, ethane, propane, and butane. For example, methane has been found in many water wells in West Virginia.
==== Ethanol drench ==== The alcohol used to clean the area to be branded as well as the alcohol in the coolant bath must have purities of 99%. This is because additives like water or iodine tend to create an alcohol slush at very cold temperatures. This slush is both an ineffective antiseptic and a very poor conductor of heat.
Proinsulin is the prohormone precursor to insulin made in the beta cells of the Pancreatic Islets, specialized regions of the pancreas. In humans, proinsulin is encoded by the INS gene. The pancreatic islets only secrete between 1% and 3% of proinsulin intact. However, because proinsulin has a longer half life than insulin, it can account for anywhere from 5–30% of the insulin-like structures circulating in the blood. There are higher concentrations of proinsulin after meals and lower levels when a person is fasting. Additionally, while proinsulin and insulin have structural differences, proinsulin does demonstrate some affinity for the insulin receptor. Due to the relative similarities in structure, proinsulin can produce between 5% and 10% of the metabolic activity similarly induced by insulin. Proinsulin is the final single chain protein structure secreted by cells before cleavage into mature insulin. Proinsulin was discovered by Professor Donald F. Steiner of the University of Chicago in 1967.
Sources: en.wikipedia.org
It binds and activates PPARδ, a nuclear receptor that influences gene expression related to fatty acid metabolism and energy balance. This mechanism has been studied mainly in animals and cell models, not established as a safe human therapy.
No. It is not an anabolic-androgenic steroid; it is a synthetic PPARδ agonist. Because it is banned in sport, it is sometimes grouped with doping agents even though its chemical class differs from steroids.
Human data are limited and development was discontinued, so major effects and long-term risks are not well characterized. Some early studies examined metabolic markers, but they do not provide a basis for unsupervised use.
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.