This is a working overview of PPARδ, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-07-13. Anything still debated is marked as such rather than presented as settled.
GW501516 acts as an agonist at the peroxisome proliferator-activated receptor delta, a nuclear receptor that regulates gene expression. Activation shifts transcription toward genes involved in fatty acid uptake, oxidation, and energy expenditure. The compound does not bind the androgen receptor and therefore differs from anabolic steroids and SARMs. In rodent models, this metabolic shift has been linked to increased running endurance and reduced fat accumulation. The exact downstream pathways in humans remain incompletely characterized.
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.
At the molecular level, GW501516 binds and activates PPARδ, a nuclear receptor that regulates transcription. Activation shifts expression of genes involved in fatty acid oxidation, energy expenditure, and lipid transport in skeletal muscle and liver. Animal studies report increased endurance and altered lipid profiles after exposure. Human data are limited to small trials and do not establish long-term safety or efficacy. PPARδ also has roles in cell proliferation, so the relationship between activation and cancer risk remains an open question.
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.
| Property | Value | Notes |
|---|---|---|
| Primary target | PPARδ | Nuclear receptor; not androgen receptor |
| Studied indications | Dyslipidemia; obesity; diabetes | Early clinical research; development discontinued |
| Rodent toxicity | Tumor formation in multiple tissues | Dose-dependent findings in some studies |
| Human approval | None | No approved therapeutic use |
| Typical analytical method | LC-MS/MS | Used for identity and quantification |
Cardarine is a common name for GW501516, a synthetic compound studied for its effects on lipid and glucose metabolism. It functions as an agonist at peroxisome proliferator-activated receptor delta, or PPARδ, a nuclear receptor that influences gene expression. The molecule is not a steroid, nor is it a selective androgen receptor modulator. It is also known in research and sports literature as GW-501516 and endurobol. Early laboratory work examined its metabolic activity in cell cultures and animal models.
Activation of PPARδ changes transcription of genes involved in fatty acid transport, mitochondrial function, and skeletal muscle fuel preference. In rodent studies, pharmacological PPARδ activation was associated with increased endurance and altered body composition. These findings generated interest in performance enhancement, but species differences and study designs limit direct extrapolation to humans. Small human trials were conducted in the 2000s and later discontinued. The extent to which cardarine produces similar metabolic or performance effects in people remains an open question.
The compound is typically described as a laboratory compound rather than a therapeutic product. Published reports have explored its role in lipid disorders, insulin sensitivity, and exercise metabolism, yet no major drug regulator has approved it for medical use. Commercial samples sold under the cardarine name may vary in purity and identity. Analytical confirmation is therefore necessary when the material is discussed in scientific or regulatory contexts. Its classification as a prohibited substance in sport further shapes how it is studied and reported.
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.
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.
ASH New Zealand stated that earlier increases in youth vaping occurred during a period before vaping products were comprehensively regulated in late 2020. In Canada reported that past-30-day vaping among youth aged 12–17 declined from 13.2% in 2019 to 7.2% in 2023. Health Canada also set a target of reducing vaping prevalence among those aged 12 to 17 to below 10% by 2025.
=== Chalcogen === Serine, homoserine, O-methylhomoserine and O-ethylhomoserine possess a hydroxymethyl, hydroxyethyl, O-methylhydroxymethyl and O-methylhydroxyethyl side chain; whereas cysteine, homocysteine, methionine and ethionine possess the thiol equivalents. The selenol equivalents are selenocysteine, selenohomocysteine, selenomethionine and selenoethionine. Amino acids with the next chalcogen down are also found in nature: several species such as Aspergillus fumigatus, Aspergillus terreus, and Penicillium chrysogenum in the absence of sulfur are able to produce and incorporate into protein tellurocysteine and telluromethionine.
The use of gas turbines to blast a large volume of high velocity water proved popular with firefighters for stubborn fires. A Hungarian team used a converted T-34 tank with two MiG-21 engines mounted to the turret to extinguish 9 fires in 43 days. The machine was known as Big Wind. In fighting a fire at a directly vertical spewing wellhead, high explosives, such as dynamite were used to create a blast wave that pushes the burning fuel and local atmospheric oxygen away from the well. (This is a similar principle to blowing out a candle.) The flame is removed and the fuel can continue to spill out without igniting. Generally, explosives were placed within 55 gallon drums, the explosives surrounded by fire retardant chemicals, and then the drums are wrapped with insulating material with a horizontal crane being used to bring the drum as close to the burning area as possible. The firefighting teams titled their occupation as "Operation Desert Hell" after Operation Desert Storm.
On July 29, 1977, H.F., a 51-year-old teacher, was attempting to remove a casserole dish from her new 600-watt microwave oven. The oven signaled the end of the heating cycle, but the light and the cooking blower were on. During retrieval of the dish, she inserted two thirds of her bare forearms into the oven, for a total time of about five seconds. The oven was still operating. She felt "hot pulsating sensation" and burning in fingers and fingernails and a sensation of "needles" over the exposed areas. Jabbing pain, swelling, and red-orange discoloration of dorsal sides of both hands and forearms appeared shortly afterwards. The next day she sought medical help. Since then, she has undergone treatment with oral and topical cortisone, Grenz rays, ultrasound, and later acupuncture, without relief. Symptoms persisted, including high sensitivity to radiant heat (sun, desk lamp, etc.) and growing intolerance to pressure of clothes and to touch in hands and forearms. Neurological examinations in 1980 and 1981 did not yield a definite diagnosis. Neuronal latencies were within norm. Electromyography discovered denervation in the median nerve, ulnar nerve, and radial nerve on both arms. Severe reduction of number of sweat glands in the finger pulps, in comparison with a random control, was also found.
Sources: en.wikipedia.org
== Diagnosis == Schwartz–Jampel syndrome is diagnosed on the basis of characteristic facial features, skeletal features and myotonia. Blood tests may show elevated serum creatine kinase or aldolase. X-rays, muscle biopsy or electromyography (EMG) may be useful. Genetic testing for the HSPG2 gene may confirm diagnosis.
The Copyright Term Directive 2006 article 1 states the principle that copyrights last for 70 years after the death of the author. The Copyright and Information Society Directive 2001 was passed to regulate copyright over the internet, and the effect of article 5 is that internet service providers are not liable for data they transmit even if it infringes copyright. However under article 6, member states must give "adequate legal protection" for copyrights. The Resale Rights Directive creates a right to royalties for authors where works are resold. The Enforcement Directive requires member states have effective remedies and legal processes. Under the European Patent Convention, which is separate from the EU, the general patent term is 20 years from the date that a patent (of an invention) is filed with an official register, and the development of an EU patent attempts to harmonise standards around these norms. The Trade Marks Directive enables a common system of trade mark registration so that, with exceptions, a registered trade mark applies across all EU member states.
where : x, y, and z are the stoichiometric coefficients of each species. M stands for metal / metal ion, the L for Lewis bases, and finally Z for complex ions. Formation constants vary widely. Large values indicate that the metal has high affinity for the ligand, provided the system is at equilibrium. Sometimes the stability constant will be in a different form known as the constant of destability. This constant is expressed as the inverse of the constant of formation and is denoted as Kd = 1/Kf . This constant represents the reverse reaction for the decomposition of a complex ion into its individual metal and ligand components. When comparing the values for Kd, the larger the value, the more unstable the complex ion is. As a result of these complex ions forming in solutions they also can play a key role in solubility of other compounds. When a complex ion is formed it can alter the concentrations of its components in the solution. For example:
Sources: en.wikipedia.org
=== Thermal === Thermal FFF, as the name suggests, establishes a separation force by applying a temperature gradient to the channel. The top channel wall is heated and the bottom wall is cooled driving polymers and particles towards the cold wall by thermal diffusion. Thermal FFF was developed as a technique for separating synthetic polymers in organic solvents. Thermal FFF is unique amongst FFF techniques in that it can separate macromolecules by both molar mass and chemical composition, allowing for the separation of polymer fractions with the same molecular weight. Today this technique is ideally suited for the characterization of polymers, gels and nanoparticles. One of the major advantage of thermal FFF is the simple and very well defined dimensions of the separation channel, which makes the inter-lab or inter-instrument universal calibration possible because the thermal FFF calibration constants closely describe the ratio of ordinary (molecular) diffusion coefficient D to thermal diffusion coefficient (or, thermophoretic mobility) DT which are only polymer dependent. The ThFFF universal calibration is, therefore, instrument and lab transferable, while the well-known size exclusion chromatography universal calibration is polymer-transferable on the same instrument only.
Male mammals typically have rudimentary mammary glands and nipples, with a few exceptions: male mice do not have nipples, male marsupials do not have mammary glands, and male horses lack nipples. The male dayak fruit bat has lactating mammary glands. Male lactation occurs infrequently in some species. Mammary glands are true protein factories, and several labs have constructed transgenic animals, mainly goats and cows, to produce proteins for pharmaceutical use. Complex glycoproteins such as monoclonal antibodies or antithrombin cannot be produced by genetically engineered bacteria, and the production in live mammals is much cheaper than the use of mammalian cell cultures.
== Further reading == De Los Angeles Beytía, Maria; Vry, Julia; Kirschner, Janbernd (2012). "Drug treatment of Duchenne musculardystrophy: available evidence and perspectives". Acta Myologica. 31 (1): 4–8. PMC 3440798. PMID 22655510. Bertini, Enrico; D'Amico, Adele; Gualandi, Francesca; Petrini, Stefania (December 2011). "Congenital Muscular Dystrophies: A Brief Review". Seminars in Pediatric Neurology. 18 (4): 277–288. doi:10.1016/j.spen.2011.10.010. PMC 3332154. PMID 22172424.
Sources: en.wikipedia.org
It targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not act primarily on androgen receptors. This distinction separates it from SARMs.
Rodent studies found dose-dependent tumors in several organs. The sponsor discontinued the program over cancer concerns. Human risk from long-term use remains unknown.
Controlled human endurance trials are lacking. Animal studies show increased exercise capacity under some conditions. Anecdotal reports are not equivalent to clinical evidence.
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.