Investigational drug raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-10-16 and is reviewed periodically as new material appears.
Cardarine is a common name for GW501516, also GW-1516, a synthetic compound developed as a peroxisome proliferator-activated receptor delta (PPARδ) agonist. It belongs to a class of agents that modulate gene transcription related to lipid and energy metabolism. The compound was studied in preclinical and early clinical research for metabolic and cardiovascular conditions, but it did not progress to approved therapeutic use. Its name appears in fitness and sports contexts despite not being approved as a drug.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | PPARδ agonist | Not an anabolic steroid. |
| Common synonyms | GW501516, GW-1516 | Cardarine is an informal name. |
| Appearance | White to off-white powder | Typical for research-grade solid. |
| Solubility class | Poorly soluble in water; soluble in some organic solvents | Such as DMSO or ethanol in laboratory settings. |
| Typical storage temperature | Cool, dry, protected from light | Specific conditions vary by supplier and form. |
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.
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.
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.
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.
=== Extraction === After cooking, the alkaline liquid (known as nejayote from Nahuatl nexayotl - nextli 'ash' y ayotl 'liquid'), containing dissolved hull, starch, and other corn matter, is decanted and discarded (or sometimes used for making amate bark paper). The kernels are washed thoroughly of remaining nejayote, which has an unpleasant flavor. The pericarp is then removed, leaving the endosperm of the grain with or without the germ, depending on the process. This hulling is performed by hand, in traditional or very small-scale preparation, or mechanically, in larger scale or industrial production. The prepared grain is called hominy, mote, or nixtamal. Nixtamal has many uses, contemporary and historic. Whole nixtamal may be used fresh or dried for later use. Whole nixtamal is used in the preparation of pozole, menudo, and other foods. Ground fresh nixtamal is made into masa (nixtamal dough) and used to make tortillas, tamales, and pupusas. Dried and ground, it is called masa harina or instant masa flour, and is reconstituted and used like masa. The term hominy may refer to whole, coarsely ground, or finely ground nixtamal, or to a cooked porridge (also called grits) prepared from any of these. Samp is similar to grits, but a product of a different process.
== Restricting methionine intake == More and more studies show that restricting methionine intake can increase the lifespan of some animals. In 2005, a study showed that restricting methionine intake without energy restriction in rodents increases their lifespan.
=== Ubiquitination of non-protein substrates === Although ubiquitination was historically considered a protein-specific post-translational modification, recent studies have shown that ubiquitin can also be conjugated to certain non-protein molecules. These include lipopolysaccharides (LPS), phospholipids and other metabolites. A notable example is the E3 ligase RNF213 which can attach ubiquitin to the lipid A moiety of bacterial LPS, promoting xenophagic clearance of invading bacteria. These findings expand the known scope of ubiquitin signaling beyond classical post-translational protein modification.
Sources: en.wikipedia.org
==== Training and qualification ==== In Europe, the training of physicians in Clinical/Medical Genetics is overseen by the Union Européenne des Médecins Spécialistes (UEMS). This organization aims to harmonize and raise the standards of medical specialist training across Europe. The UEMS has established European Training Requirements (ETR) for Medical Genetics to guide the education and training of medical geneticists. Individuals seeking acceptance into clinical genetics training programs must hold an MD, or in some countries, an MB ChB or MB BS degree. These qualifications ensure that trainees have the foundational medical knowledge required to specialize in Medical Genetics. The optimal training program involves a total of five years: one year of general medical training (the "common trunk", often covering fields such as general practice, pediatrics, obstetrics and gynecology, neurology, psychiatry, and internal medicine) followed by four years of specialized training in Medical Genetics. This specialized training should include at least two years of clinical patient care and at least six months in genetic laboratory diagnostics. Trainees' progress is evaluated through a structured program that begins with observation and progresses to independent practice under supervision, culminating in the ability to manage complex cases independently. Final certification involves a comprehensive assessment, which may include national examinations or the European Certificate in Medical Genetics and Genomics (ECMGG).
. Due to the high purity of the reagent ions a mass filter between the ion source and the reaction drift tube is not necessary and H3O+ can be injected directly. The absence of this mass filter in turn greatly reduces losses of reagent ions and leads eventually to an outstandingly low detection limit of the whole instrument. In the reaction drift tube a vacuum pump is continuously drawing through air containing the VOCs one wants to analyze. At the end of the drift tube the protonated molecules are mass analyzed (quadrupole mass analyzer or time-of-flight mass spectrometer) and detected. As an alternative to H3O+ already in early PTR-MS related publications the use of NH4+ reagent ions has been suggested. Ammonia has a proton affinity of 853.6 kJ/mol. For compounds that have a higher proton affinity than ammonia proton transfer can take place similar to the process described above for hydronium:
Isoergine, also known as isolysergic acid amide (iso-LSA or iso-LA-819), isolysergamide, or erginine, is a serotonergic psychedelic of the ergoline and lysergamide families related to ergine (lysergic acid amide; LSA) and lysergic acid diethylamide (LSD). It is the epimer of ergine inverted at the 8 position. Along with ergine and other ergolines, isoergine occurs naturally in morning glories. It is thought to be primarily responsible for the hallucinogenic effects of morning glory seeds.
Sources: en.wikipedia.org
Andy Street, the Mayor of the West Midlands, announces that he and his Manchester counterpart, Andy Burnham, are to meet Mark Harper, the Secretary of State for Transport, to discuss proposals for a privately funded alternative to the abandoned Manchester leg of HS2. The UK is to lend several pieces of the Ghana crown jewels back to Ghana 150 years after looting them from the court of the Asante king. 25 January The UK government announces fresh plans to ban the sale of zombie knives, with legislation taking effect from the autumn. Lloyds Banking Group announces plans to cut around 1,600 positions from its branch staff in a reorganisation that it says is because more customers are banking online. 26 January Buckingham Palace confirms that King Charles III has been admitted to hospital for treatment for an enlarged prostate. Jürgen Klopp, currently the longest-serving manager in the Premier League, announces he is departing as manager of Liverpool F.C. after the conclusion of the 2023–24 season, and taking a break from football management. 27 January The UK government suspends funding for the UN agency for Palestinian refugees, UNRWA, after the organisation sacked several officials reported to have been involved in the 7 October attacks on Israel. Kemi Badenoch, the business secretary, asks Henry Staunton to step down as chair of Post Office Limited after 13 months in the role, as the government moves to strengthen governance at the Post Office in the wake of the long-running Horizon IT scandal.
=== Birds and reptiles === The epidermis of birds and reptiles is closer to that of mammals, with a layer of dead keratin-filled cells at the surface, to help reduce water loss. A similar pattern is also seen in some of the more terrestrial amphibians such as toads. In these animals, there is no clear differentiation of the epidermis into distinct layers initially, as occurs in humans, with the change in cell type being relatively gradual. The mammalian epidermis always possesses at least a stratum germinativum and stratum corneum, but the other intermediate layers found in humans are not always distinguishable. Hair is a distinctive feature of mammalian skin, while feathers are (at least among living species) similarly unique to birds. Birds and reptiles have relatively few skin glands, although there may be a few structures for specific purposes, such as pheromone-secreting cells in some reptiles, or the uropygial gland of most birds.
== Applications == Microfluidic structures include micropneumatic systems, i.e. microsystems for the handling of off-chip fluids (liquid pumps, gas valves, etc.), and microfluidic structures for the on-chip handling of nanoliter (nl) and picoliter (pl) volumes. To date, the most successful commercial application of microfluidics is the inkjet printhead. Additionally, microfluidic manufacturing advances mean that makers can produce the devices in low-cost plastics such as polymethymethacrylate (PMMA), polystyrene, cyclic olefin polymer (COP) and polyvinyl chloride (PVC) and automatically verify part quality. Microfluidic devices are often first produced using fabrication methods such as soft lithography, micro milling or laser machining to validate microchannel designs before transitioning to scalable thermoplastic manufacturing processes such as injection molding. Advances in microfluidics technology promise to improve molecular biology procedures for enzymatic analysis (e.g., glucose and lactate assays), DNA analysis (e.g., polymerase chain reaction and high-throughput sequencing), proteomics, and in chemical synthesis. Microfluidic biochips integrate assay operations such as detection, with sample pre-treatment and sample preparation. A promising application area for biochips is clinical pathology, especially the point-of-care diagnosis of diseases.
=== COVID-19 pandemic === On 20 January 2020, Xi commented for the first time on the emerging COVID-19 pandemic in Wuhan, and ordered "efforts to curb the spread" of the virus. He gave premier Li Keqiang some responsibility over the COVID-19 response, in what has been suggested by The Wall Street Journal was an attempt to potentially insulate himself from criticism if the response failed. The government initially responded to the pandemic with a lockdown and censorship, with the initial response causing widespread backlash within China. Xi met with Tedros Adhanom Ghebreyesus, the director-general of the World Health Organization (WHO), on 28 January. Der Spiegel reported that in January 2020 Xi pressured Tedros Adhanom to hold off on issuing a global warning about the outbreak of COVID-19 and hold back information on human-to-human transmission of the virus, allegations denied by the WHO. On 5 February, Xi met with Cambodian prime minister Hun Sen in Beijing, the first foreign leader allowed into China since the outbreak. After the COVID-19 outbreak got under control in Wuhan, Xi visited the city on 10 March. After getting the outbreak in Wuhan under control, Xi has favoured what has officially been termed "dynamic zero-COVID policy" that aims to control and suppress the virus as much as possible within the country's borders. This has involved local lockdowns and mass-testing.
Sources: en.wikipedia.org
Cardarine is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.
No, cardarine is not a steroid. It is classified as a PPARδ agonist. Its structure and receptor target differ from anabolic steroids.
No regulatory agency has approved cardarine as a medicine. It was investigated in early research but development was discontinued. It is not available as a prescription drug.
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.