If you have been reading about GW501516 and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-03-28. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular target | PPAR delta (NR1C2) | Ligand-activated nuclear receptor. |
| Primary tissues studied | Skeletal muscle, liver, adipose | Effects on fatty acid oxidation and energy use. |
| Typical detection matrix | Urine | Used in anti-doping analysis. |
| Common analytical method | LC-MS/MS | Detects parent compound and metabolites. |
| Sport regulatory class | Prohibited at all times | Listed as a metabolic modulator by WADA. |
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.
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.
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.
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.
Laboratory studies have examined GW501516 in cell cultures and rodents for conditions such as dyslipidemia, insulin resistance, and obesity. Some trials in humans were initiated, but development was discontinued after preclinical findings raised concerns about cancer in certain models. Those findings do not prove that the compound causes cancer in people, but they contributed to regulatory caution. Later reviews often describe the evidence as preliminary and insufficient for assessing long-term safety.
== Predicted properties == Very few properties of flerovium or its compounds have been measured; due to its extremely limited and expensive production and the fact that it decays very quickly. A few singular properties have been measured, but for the most part, properties of flerovium remain unknown and only predictions are available.
Amino Acid + ATP + tRNA → Aminoacyl-tRNA + AMP + PPi The net reaction is energetically favorable only because the pyrophosphate (PPi) is later hydrolyzed. The hydrolysis of pyrophosphate to two molecules of inorganic phosphate (Pi) reaction is highly energetically favorable and drives the other two reactions. Together, these highly exergonic reactions take place inside the aminoacyl-tRNA synthetase specific for that amino acid.
(2026) report evidence from the study of carbon and oxygen stable isotope compositions of mammal fossils from the Pinturas Formation (Argentina) indicative of presence of a diverse range of habitats in Patagonia during the Miocene, and interpret the diversity of the primate assemblage from the studied formation as likely linked to habitat diversity. Cooke et al. (2026) report the first discovery of mandibular remains of Stirtonia victoriae from the La Victoria Formation (Colombia), and interpret their anatomy as indicative of leaf-eating adaptations of the studied monkey. Urciuoli et al. (2026) determine the phylogenetic relationships of early members of Catarrhini on the basis of the study of the semicircular canal and vestibule shape in Saadanius, Pliobates, Ekembo and Victoriapithecus, interpret Saadanius as most likely to be a stem catarrhine that evolved ossified tubular ectotympanic independently from crown catarrhines, and interpret pliopithecoids as most likely to be stem catarrhines closer to the crown group than Saadanius. Arias-Martorell et al. (2026) report evidence of similarities of shape of the radial head of Pliobates cataloniae and extant apes, and interpret Pliobates as better adapted to climbing than to behaviors involving forelimb-dominated suspension. Arias-Martorell et al. (2026) compare the shape of the distal part of the humerus of Pliobates cataloniae and other extinct and extant simians, and interpret Pliobates as unlikely to perform acrobatic suspensory behaviors seen in extant gibbons.
Sources: en.wikipedia.org
== Nomenclature == This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is N5-(L-1-carboxyethyl)-L-ornithine:NADP+ oxidoreductase (L-ornithine-forming). Other names in common use include 5-N-(L-1-carboxyethyl)-L-ornithine:NADP+ oxidoreductase, and (L-ornithine-forming).
Higher temperatures accelerate germination, with 23 °C (73 °F) promoting faster colony formation than 19 °C (66 °F). Light exposure is unnecessary for early fungal growth—cultures in darkness develop healthier, more extensive mycelial networks. Developing mycobiont morphology provides insights into early symbiosis. In vitro, X. parietina forms septate, branched hyphae, which later develop into lobed structures, resembling early lichen thalli. Scanning electron microscopy reveals a dense, interwoven hyphal network, potentially facilitating photobiont interactions during natural lichenization. These adaptations support X. parietina's regenerative ability and symbiotic establishment across varied environments. Although X. parietina lacks specialized vegetative propagules, it has a regenerative capacity that enhances its ecological success. Older, apothecia-covered thalli detach along drought-induced cracks, while younger margins remain attached. When fragments land on suitable substrates, they regenerate new lobes along wound margins, acting as natural propagules. Field studies show a 150% laminal size increase in just 13 months in regenerating thalli. In a five-year experiment, X. parietina maintained 50% substrate coverage, despite losing 90% of its initial thallus area, as regrowth compensated for these losses. Total turnover (growth + loss) exceeded 170%, highlighting its dynamic life cycle.
== Mechanism of action == Icotrokinra is a targeted oral peptide that selectively binds to and blocks the interleukin 23 receptor (IL-23R), thereby inhibiting IL-23-mediated signaling. The drug demonstrates high affinity for the human IL-23 receptor with a dissociation constant (KD) of 7.1 pM and inhibits IL-23-induced STAT3 phosphorylation in peripheral blood mononuclear cells with an IC50 of 5.6 pM. The IL-23 pathway plays a central role in the inflammatory cascade underlying various autoimmune conditions, particularly those involving Th17 cells. Unlike injectable biologics that target IL-23 or its receptor, icotrokinra offers the convenience of oral administration while maintaining selective receptor binding.
Sources: en.wikipedia.org
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.
Early-stage trials examined lipid and glucose markers, but the development program was discontinued. Published human results are limited and do not support approved use for any indication. Claims of performance or health benefits remain unproven.
Yes. Laboratories use LC-MS/MS to detect GW501516 and its metabolites in urine. Detection depends on timing and sensitivity, but the substance is banned at all times.
Yes, WADA prohibits cardarine as a PPARδ agonist. It appears on the prohibited list and can be detected in urine or blood. Athletes using it risk sanctions.