Everything below concerns GW501516. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-10-20. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
Cardarine is a common name for GW501516, a synthetic compound first described in the 1990s as a selective agonist of the peroxisome proliferator-activated receptor delta. It was studied in preclinical models for metabolic and cardiovascular conditions, but it has not been approved as a medicine in the United States, Europe, or other major jurisdictions. Retail products labeled as cardarine are generally research chemicals or supplements, not pharmaceutical formulations. Because human safety and efficacy data remain limited, regulatory agencies treat it as an unapproved substance rather than a therapeutic product.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport | Listed by WADA as a metabolic modulator. |
| Approved medical use | None in major jurisdictions | Not a registered drug. |
| Common test matrix | Urine | Most anti-doping samples use urine. |
| Typical detection method | LC-MS/MS | Detects parent compound and metabolites. |
| Reference standard storage | -20 °C, desiccated | Typical for analytical standards. |
Safety discussions about cardarine frequently cite rodent carcinogenicity findings reported in the 2000s. In those studies, treated animals developed tumors at multiple sites, leading sponsors to discontinue clinical development. The relevance of these findings to humans has not been resolved, but they are a major reason the compound is not approved. Current literature emphasizes uncertainty about long-term effects and the risks of unregulated use. Regulators and health agencies have not established a safe human exposure level.
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.
Laboratory handling focuses on identity, purity, and stability. Reference standards are typically stored cold and dry, protected from light, because solutions can degrade over time. Analytical checks may use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Impurities and related substances can be separated chromatographically and compared with a known standard. Because cardarine is not an approved drug, compendial monographs are absent, and laboratories often rely on in-house methods. Reported purity varies among unregulated products and should not be assumed from a label.
GW501516 binds and activates PPARδ, a nuclear receptor that influences transcription of genes involved in fatty acid oxidation and energy use. Activation shifts some metabolic pathways in preclinical models, which is why the compound has been studied for lipid disorders and exercise-related endpoints. The exact downstream effects in humans are incompletely mapped. PPARδ is expressed in many tissues, including skeletal muscle, liver, and adipose tissue, so broad activation may have varied consequences. Researchers continue to examine how selective or partial activation might alter the balance between benefits and risks.
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 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.
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.
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.
As of 2012, the United States National Helium Reserve accounted for 30 percent of the world's helium. The reserve was expected to run out of helium in 2018. Despite that, a proposed bill in the United States Senate would allow the reserve to continue to sell the gas. Other large reserves were in the Hugoton in Kansas, United States, and nearby gas fields of Kansas and the panhandles of Texas and Oklahoma. New helium plants were scheduled to open in 2012 in Qatar, Russia, and the US state of Wyoming, but they were not expected to ease the shortage. In 2013, Qatar started up the world's largest helium unit, although the 2017 Qatar diplomatic crisis severely affected helium production there. 2014 was widely acknowledged to be a year of over-supply in the helium business, following years of renowned shortages. Nasdaq reported (2015) that for Air Products, an international corporation that sells gases for industrial use, helium volumes remain under economic pressure due to feedstock supply constraints.
=== Nanoparticles === Nanoparticles 40 nm in diameter and smaller have been successful in penetrating the skin. Research confirms that nanoparticles larger than 40 nm do not penetrate the skin past the stratum corneum. Most particles that do penetrate will diffuse through skin cells, but some will travel down hair follicles and reach the dermis layer. The permeability of skin relative to different shapes of nanoparticles has also been studied. Research has shown that spherical particles have a better ability to penetrate the skin compared to oblong (ellipsoidal) particles because spheres are symmetric in all three spatial dimensions. One study compared the two shapes and recorded data that showed spherical particles located deep in the epidermis and dermis whereas ellipsoidal particles were mainly found in the stratum corneum and epidermal layers. Nanorods are used in experiments because of their unique fluorescent properties but have shown mediocre penetration. Nanoparticles of different materials have shown skin's permeability limitations. In many experiments, gold nanoparticles 40 nm in diameter or smaller are used and have shown to penetrate to the epidermis. Titanium oxide (TiO2), zinc oxide (ZnO), and silver nanoparticles are ineffective in penetrating the skin past the stratum corneum. Cadmium selenide (CdSe) quantum dots have proven to penetrate very effectively when they have certain properties. Because CdSe is toxic to living organisms, the particle must be covered in a surface group.
In biochemistry, isozymes (also known as isoenzymes or more generally as multiple forms of enzymes or isoforms) are enzymes that differ in amino acid sequence but catalyze the same chemical reaction. Isozymes usually have different kinetic parameters (e.g. different KM values), or are regulated differently. They permit the fine-tuning of metabolism to meet the particular needs of a given tissue or developmental stage. In many cases, isozymes are encoded by homologous genes that have diverged over time. Strictly speaking, enzymes with different amino acid sequences that catalyse the same reaction are isozymes if encoded by different genes, or allozymes if encoded by different alleles of the same gene; the two terms are often used interchangeably.
Upon completion, the ship left on October 28, 1613, for Acapulco in New Spain, with around 180 people on board, consisting of 10 samurai of the shōgun (led by the Minister of the Navy Mukai Shōgen Tadakatsu), 12 samurai from Sendai, 120 Japanese merchants, sailors, and servants, and around 40 Spaniards and Portuguese. The ship arrived in Acapulco on January 25, 1614, after three months at sea. After a year in Acapulco, the ship returned to Japan on April 28, 1615, as Hasekura continued to Europe. It seems that around 50 specialists in mining and silver-refining were invited to Japan on this occasion, so that they could help develop the mining industry in the Sendai area. A group of Franciscans led by Father Diego de Santa Catalina, sent as a religious embassy to Tokugawa Ieyasu also sailed on the ship. The San Juan Bautista arrived in Uraga, Japan on August 15, 1615. In September 1616 the San Juan Bautista headed again to Acapulco, at the request of Luis Sotelo. She was sailed by Captain Yokozawa Shōgen, but the trip went wrong and around 100 sailors died en route. San Juan Bautista finally arrived in Acapulco in May 1617. Sotelo and Hasekura met in Mexico for the return trip back to Japan. In April 1618 the ship arrived in the Philippines, where she was sold to the Spanish government there with the objective of building up defenses against the Dutch. Hasekura returned to Japan in 1620. During his absence Japan had changed quite drastically: Christianity was being eradicated, and Japan was moving towards a period of seclusion.
Sources: en.wikipedia.org
=== International reactions === The attacks were denounced by mass media and governments worldwide. Nations offered pro-American support and solidarity. Leaders in most Middle Eastern countries, as well as Libya and Afghanistan, condemned the attacks. Iraq was a notable exception, with an immediate official statement that "the American cowboys are reaping the fruit of their crimes against humanity." The government of Saudi Arabia officially condemned the attacks, but privately many Saudis favored bin Laden's cause. Although Palestinian Authority (PA) president Yasser Arafat also condemned the attacks, there were reports of celebrations of disputed size in the West Bank, Gaza Strip, and East Jerusalem. Arafat ordered his security services to break up the celebrations and tried to obstruct news organizations from showing them. The PA claimed that such celebrations do not represent Palestinian sentiment overall. Footage by CNN and other news outlets were suggested by a report originating at a Brazilian university to be from 1991; this was later proven to be a false accusation. As in the United States, the aftermath of the attacks saw tensions increase in other countries between Muslims and non-Muslims. United Nations Security Council Resolution 1368 condemned the attacks and expressed readiness to take all necessary steps to respond and combat terrorism in accordance with their Charter. Numerous countries introduced anti-terrorism legislation and froze bank accounts they suspected of al-Qaeda ties.
In 1993, Jeffrey Ulmer and co-workers at Merck Research Laboratories demonstrated that direct injection of mice with plasmid DNA encoding a flu antigen protected the animals against subsequent experimental infection with influenza virus. In 2016 a DNA vaccine for the Zika virus began testing in humans at the National Institutes of Health. The study was planned to involve up to 120 subjects aged between 18 and 35. Separately, Inovio Pharmaceuticals and GeneOne Life Science began tests of a different DNA vaccine against Zika in Miami. The NIH vaccine is injected into the upper arm under high pressure. Manufacturing the vaccines in volume remained unsolved as of August 2016. Clinical trials for DNA vaccines to prevent HIV are underway. In August 2021, Indian authorities gave emergency approval to ZyCoV-D. Developed by Cadila Healthcare, it is the first DNA vaccine against COVID-19.
== Description == Typical Catostylus with chunky appendages and tentacle to go with each. This jellyfish has a sting that causes light pain and a skin rash, but generally poses no serious threat. It is up to 65 cm (26 in) in bell diameter, but a more typical size is 25 cm (10 in) in diameter and 2.5 kg (5.5 lb) in weight. Its colour is variable and can be blue-white, cream, brown, or off-white. The exumbrellar grooves are reddish or purplish brown. C. tagi has gonads along the edge of its stomach in an X shape. It has the octant formation typical of Catostylus jellies, the height of the octants are also variable.
==== CYP2D6 inhibition ==== Doxepin has been identified as an inhibitor of CYP2D6 in vivo in a study of human patients being treated with 75 to 250 mg/day for depression. While it significantly altered metabolic ratios for sparteine and its metabolites, doxepin did not convert any of the patients to a different metabolizer phenotype (e.g., extensive to intermediate or poor). Nonetheless, inhibition of CYP2D6 by doxepin could be of clinical importance.
In 1998 Andrew Wakefield et al. published a fraudulent paper about twelve children, reportedly with bowel symptoms and autism or other disorders acquired soon after administration of MMR vaccine, while supporting a competing vaccine. In 2010, Wakefield's research was found by the General Medical Council to have been "dishonest", and The Lancet fully retracted the paper. Three months following The Lancet's retraction, Wakefield was struck off the UK medical register, with a statement identifying deliberate falsification in the research published in The Lancet, and was barred from practising medicine in the UK. The research was declared fraudulent in 2011 by the British Medical Journal. Since Wakefield's publication, multiple peer-reviewed studies have failed to show any association between the vaccine and autism. The US Centers for Disease Control and Prevention, the Institute of Medicine of the US National Academy of Sciences, the UK National Health Service and the Cochrane Library review have all concluded that there is no evidence of a link. Administering the vaccines in three separate doses does not reduce the chance of adverse effects, and it increases the opportunity for infection by the two diseases not immunized against first. However, on August 10, 2026, US president Donald Trump signed an executive order requiring the MMR vaccine to be split into three separate shots, and recommending that "to the maximum extent feasible, all childhood immunizations should be administered at separate medical visits".
Sources: en.wikipedia.org
Legal status varies by country, but cardarine is not approved as a medicine in major jurisdictions. It is often sold as a research chemical, a category that may not be lawful for human use. Buyers should check local laws and product labels carefully.
Anti-doping laboratories use LC-MS/MS to detect GW501516 and its metabolites, usually in urine. The method can identify the parent compound at low concentrations. Detection windows vary with dose and individual factors.
No, cardarine has no approved medical uses in major jurisdictions. Early research explored metabolic conditions, but those programs were discontinued. It is not a registered treatment for any disease.
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.