Everything below concerns Anti-doping. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-01-28. Numbers and descriptions here follow the published literature rather than marketing material.
Human trials of GW501516 were small and short in duration. They examined lipid levels, glucose handling, and other metabolic markers, but the programs were halted after the animal cancer findings. No approved therapeutic product exists, and published human data are insufficient for establishing long-term safety. Reports of use for athletic performance come mainly from non-clinical settings and cannot be verified through controlled trials. Independent testing of products sold as cardarine has found inconsistent purity and labeling.
Laboratory studies indicate that GW501516 activates PPARδ, a nuclear receptor involved in fatty acid oxidation and energy metabolism. In rodent experiments, treated animals often showed increased endurance and reduced fat mass. These effects were observed under controlled conditions and do not establish safe or effective use in humans. The exact dose-response relationship in humans remains poorly characterized. Species differences in metabolism can affect how results translate across animals and people.
Safety concerns emerged from long-term animal studies. In rodents given the compound for extended periods, researchers found an increased incidence of certain cancers, including liver and bladder tumors. These findings contributed to the discontinuation of clinical development. Whether similar risks apply to short-term or low-level exposure in humans is not established, and controlled human safety data are limited. The relevance of high-dose rodent carcinogenicity findings to human use remains a subject of debate.
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.
| Property | Value | Notes |
|---|---|---|
| Primary target | PPARδ (NR1C2) | Nuclear receptor involved in lipid metabolism |
| Preclinical effect | Increased fatty acid oxidation | Observed in rodent studies |
| Key safety signal | Tumors in rodents after long-term exposure | Contributed to halted clinical development |
| Human trial status | No approved product; development stopped | Limited short-term metabolic data |
| Sport regulatory status | Prohibited at all times | WADA hormone and metabolic modulators class |
A common misconception is that cardarine has been proven safe for human use. In reality, human clinical data are limited, and long-term animal studies have raised concerns about cancer. Another misconception is that it is a supplement or vitamin-like compound. It is a synthetic research chemical with no approved medical indication. Scientific discussion often focuses on its mechanism and detection rather than therapeutic use. Regulatory and anti-doping literature treats it primarily as a prohibited substance.
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.
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.
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.
Guanosine monophosphate synthetase, (EC 6.3.5.2) also known as GMPS is an enzyme that converts xanthosine monophosphate to guanosine monophosphate. In the de novo synthesis of purine nucleotides, IMP is the branch point metabolite at which point the pathway diverges to the synthesis of either guanine or adenine nucleotides. In the guanine nucleotide pathway, there are 2 enzymes involved in converting IMP to GMP, namely IMP dehydrogenase (IMPD1), which catalyzes the oxidation of IMP to XMP, and GMP synthetase, which catalyzes the amination of XMP to GMP.
The smallpox vaccine has also proven useful in preventing emergent infectious diseases caused by closely-related orthopoxviruses such as Mpox. Three specific smallpox vaccines have been approved in at least one country for Mpox prevention: MVA-BN, LC16m8, and ACAM2000. The Mpox vaccine is on the World Health Organization's List of Essential Medicines.
Although the general abstraction can be this simple one must remember that the detalis of this type of processes are highly complex and only recently better understood. Another general pattern observed is that, although remodeling is an inherently microscopical phenomena, there are emergent function and order that arises from the interaction single remodeling agents. The most common way in which this happen is due to single cells trying to reach a local homeostasis, and by doing so actually give rise to a macroscopic function (optimization, healing etc.) and more generally functional structural changes. One very good example of this is the case of fibroblasts in collagen matrix. The remodeling in this case, as explained in the reference, is due to the alignment of the collagen fibers with the principal directions of stress actuated by the fibroblasts. The interesting part is that they do so in such a way as to reach a "stress homeostasis": although the tissue is forced in tension they perceive none, but only after they have remodeled the neighboring as to create an effective stress shield by reinforcing the material where needed. When the tissue is relaxed again, they find themselves in an unnaturally stressed position and change their surroundings trying to reach again a zero stress state (the original one). In reaching such dynamic equilibrium fibroblasts further cooperate by disposing themselves in lines. In this way it's easier to "shield" themselves (as it is more efficient to build houses one right next to the other).
== Career == Bhatia began her academic career in 1998, joining the bioengineering faculty at the University of California, San Diego (UCSD). As an assistant professor, she was awarded a five-year Packard Fellowship for Science and Engineering from the David and Lucile Packard Foundation in 1999. She was recognized with a "Teacher of the Year" award at the Jacobs School of Engineering in 2001, and was named an "Innovator under 35" by MIT Technology Review in 2003. Bhatia co-authored the first undergraduate textbook on tissue engineering, Tissue engineering (2004), written for senior-level and first-year graduate courses with Bernhard Palsson. She was a co-editor of Microdevices in Biology and Medicine (2009) and Biosensing: International Research and Development (2005). In 2005, she joined the MIT faculty in the Division of Health Sciences & Technology and the Department of Electrical Engineering and Computer Science. The Scientist named her a "Scientist to Watch" in 2006, and she became a Howard Hughes Medical Institute Investigator in 2008. Since 2013, Bhatia has expanded her affiliations within MIT and Harvard, including the Ludwig Center for Molecular Oncology (2013), the Broad Institute of MIT and Harvard (2014), the MIT Center for Neurobiological Engineering (2016), the Wyss Institute for Biologically Inspired Engineering (2018), and the Martin Trust Center for MIT Entrepreneurship (2022). Bhatia currently directs the Laboratory for Multiscale Regenerative Technologies and the Marble Center for Cancer Nanomedicine at MIT.
=== Cardiovascular disease === PCT serves a marker to help differentiate acute respiratory illness such as infection from an acute cardiovascular concern. It also has value as a prognostic lab value in patients with atherosclerosis or coronary heart disease as its levels correlate with the severity of the illness. The European Society of Cardiology recently released a PCT-guided algorithm for administering antibiotics in patients with dyspnea and suspected acute heart failure. The guidelines use a cut off point of .2 ng/mL and above as the point at which to give antibiotics. This coincides with a 2017 review of literature which concluded that PCT can help reduce antibiotic overuse in patients presenting with acute heart failure. In regards to mortality, a meta analysis of over 5000 patients with heart failure concluded that elevated PCT was reliable in predicting short term mortality.
Sources: en.wikipedia.org
The successes of Josip Broz Tito's Yugoslav partisans in Dalmatia led the Allies to despatch small patrols into Yugoslavia and Albania to contact partisan leaders and arrange co-operation with the Allied air forces. Several Rhodesian patrols from the LRDG were selected to undertake such missions during August and September 1944. Yugoslav partisans subsequently indicated targets for Allied bombing missions, with some success. From September, members of the LRDG's Rhodesian squadron under Captain Olivey undertook advanced reconnaissance in the Peloponnese peninsula of southern Greece. Landing at Katakolo, they made their way inland to Corinth and, along with the British 4th Parachute Battalion, entered Athens as the Germans departed in November. The Rhodesians of the LRDG spent November and December helping Greek forces to garrison an Athens orphanage against supporters of the communist Greek People's Liberation Army. Four Rhodesians were killed. The LRDG returned to Yugoslavia in February 1945, operating around Istria and Dalmatia, where Germany still held portions of the mainland and certain strategic islands. The Germans had heavily mined the southern Adriatic and were attempting to cover their shipping by moving only by night, close to shore, and heaving to during the day under camouflage nets. The LRDG was tasked to patrol the coast, find the ships and report their locations to the air force for bombing. This it did with success. It remained in Yugoslavia for the rest of the war.
Body fat cells have regional responses to the overfeeding that was studied in adult subjects. In the upper body, an increase of adipocyte size correlated with upper-body fat gain; however, the number of fat cells was not significantly changed. In contrast to the upper body fat cell response, the number of lower-body adipocytes did significantly increase during the course of experiment. Notably, there was no change in the size of the lower-body adipocytes. Approximately 10% of fat cells are renewed annually at all adult ages and levels of body mass index without a significant increase in the overall number of adipocytes in adulthood.
== External links == Clinical trial number NCT02229851 for "Trial to Compare the Efficacy and Safety of NNC0195-0092 (Somapacitan) With Placebo and Norditropin FlexPro (Somatropin) in Adults With Growth Hormone Deficiency. (REAL 1)" at ClinicalTrials.gov
The colonization of Tahiti occurred in a time of rivalry for resources of the Pacific by colonizing European nations including the French and the British. It was also a time of rivalry and fighting between the people of Tahiti and neighbouring islands. It is unclear which is the first European ship to arrive at the island of Tahiti but it is often recognised as being HMS Dolphin captained by British Captain Samuel Wallis on 18 June 1767. He met a welcoming party of Tahitians who traded with him. Cultural differences leading to grave communication errors that resulted in a battle in Matavai Bay between three hundred war canoes and HMS Dolphin which fired on the war canoes with muskets, quarterdeck guns and then cannons. The Tahitian chief Obera (Purea) ordered peace offerings from her people after this battle and Wallis and the Tahitians departed on amicable terms when he left on 27 July 1767. A few months later the French arrived on 2 April 1768 with the ships Boudeuse and Etoile captained by Louis-Antoine de Bougainville.
=== Selenophosphate synthetase === The production of selenoprotein cannot occur without selenophosphate, which is produced by selenophosphate synthetase. Vertebrates including humans carry two versions of this enzyme, with one (SEPHS2) being a selenoprotein and the other (SEPHS1) replacing it with a threonine, though still with a vestigial SECIS element. Analysis of animal versions of this enzyme show that the original animal version is a selenoprotein, with SEPHS1 arising later through gene duplication. Among prokaryotes, most bacteria have a version with cystine instad of selenocystine, suggesting that this may be the ancestral state (which would avoid the chicken-and-egg problem). Some have two versions, one with Sec and the other with Cys. Archaea mostly have the Sec version.
Sources: en.wikipedia.org
Rodent studies reported increased endurance and fat oxidation after GW501516 exposure. Long-term studies also found higher rates of some tumors, which led to halted development.
Small short-term human trials examined metabolic markers such as lipids and glucose. The trials did not continue after rodent cancer findings, so long-term human safety is unknown.
Controlled human trials have not established a performance benefit. Anecdotal reports exist, but they are not reliable evidence.
It binds to and activates PPAR delta, a nuclear receptor that controls expression of genes related to fatty acid oxidation. This mechanism can alter energy metabolism in animal models. It is not a direct stimulant or fat-burning enzyme.