A practical reference on GW501516: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
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 human data are sparse and mostly come from early-phase trials. Those studies examined short-term changes in lipids, glucose, and exercise capacity, but they were not large enough to establish efficacy or long-term safety. Some animal experiments reported increased running endurance, yet such findings do not prove a performance benefit in people. Anti-doping laboratories detect GW501516 and its metabolites in urine or blood using liquid chromatography-tandem mass spectrometry. Detection windows depend on dose, sample type, and individual metabolism. The method is sensitive enough to identify trace residues in tested samples.
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.
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 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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white solid | Typical form of reference material |
| Solubility | Low in water; soluble in DMSO | Used to prepare stock solutions |
| Typical storage | -20 °C, desiccated, protected from light | Common laboratory practice |
| Analytical method | LC-MS/MS | Detects parent compound and metabolites |
| Common test matrix | Urine or blood | Used in anti-doping analysis |
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.
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.
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.
== Properties == Pure avobenzone is a whitish to yellowish crystalline powder with a weak odor, dissolving in isopropanol, dimethyl sulfoxide, decyl oleate, capric acid/caprylic, triglycerides and other oils. It is not soluble in water. Avobenzone is a dibenzoylmethane derivative. Avobenzone exists in the ground state as a mixture of the enol and keto forms, favoring the chelated enol. This enol form is stabilized by intramolecular hydrogen-bonding within the β-diketone. Its ability to absorb ultraviolet light over a wider range of wavelengths than many other sunscreen agents has led to its use in many commercial preparations marketed as "broad spectrum" sunscreens. Avobenzone has an absorption maximum of 357 nm.
== Classification == Routes of administration are usually classified by application location (or exposition). The route or course the active substance takes from application location to the location where it has its target effect is usually rather a matter of pharmacokinetics (concerning the processes of uptake, distribution, and elimination of drugs). Exceptions include the transdermal or transmucosal routes, which are still commonly referred to as routes of administration. The location of the target effect of active substances is usually rather a matter of pharmacodynamics (concerning, for example, the physiological effects of drugs). An exception is topical administration, which generally means that both the application location and the effect thereof is local. Topical administration is sometimes defined as both a local application location and local pharmacodynamic effect, and sometimes merely as a local application location regardless of location of the effects.
== Synthesis == SRTXs are abundant in venoms, whereas ETs are present in a low concentration in mammals. Both ETs and SRTXs are generated in vivo by proteolytic cleavage from larger precursors. They also can be produced by solid phase peptide synthesis and fold spontaneously in vitro in high yield into native tertiary structures, with the correct disulfide bond pairing of cysteines. SRTXs complete cDNA sequence comprises 1948 base pairs (bp) coding for a pre-pro-polypeptide of 543 amino acids, which starts with a methionine that initiates translation followed by a hydrophobic peptide characteristic of a signal sequence. The amino acid sequence comprises one sequence of 39 amino acidic residues followed by 11 sequences of 40 residues, each of it contains one SRTX sequence preceded by 19 spacer amino acids. The SRTX-c isoform is the most abundant in the venom and is also the isoform with the greatest number of copies (five in all) in the precursor.
== Contraindications == Benzodiazepines require special precaution if used in the elderly, during pregnancy, in children, alcohol- or drug-dependent individuals, and individuals with comorbid psychiatric disorders. As with many other drugs, changes in liver function associated with aging or diseases such as cirrhosis, may lead to impaired clearance of nordazepam.
Sources: en.wikipedia.org
Critical response to Ellipse was generally positive. At Metacritic, which assigns a normalized rating out of 100 to reviews from mainstream critics, the album received an average score of 68, based on 12 reviews. It also earned her a further two Grammy Nominations on 2 December for Best Pop Instrumental Performance for "The Fire" and Best Engineered Non-Classical Album. On 31 January 2010, it was announced that Heap had won the latter award.
==== Mastocytosis ==== Mastocytosis involves both excessive accumulation and activation of mast cells and is considered a primary type of mast cell activation disorder (MCAD). Mastocytosis is a rare clonal mast cell disorder involving rapid, uncontrolled cell growth and the presence of too many mast cells (mastocytes). The most commonly affected organs in mastocytosis are bone marrow, skin, liver, spleen, and lymph nodes. Symptoms of mastocytosis depend upon the organs involved. In 2016, the World Health Organization (WHO) classified mastocytosis as cutaneous (CM, skin only), systemic (SM, involving at least one additional organ) or mast cell sarcoma (MCS, involving rapidly spreading solid tumors). In 2022, WHO divided SM into subcategories which include the less advanced forms of bone marrow mastocytosis (BMM), indolent systemic mastocytosis (ISM), smoldering systemic mastocytosis (SSM), and the more advanced forms of aggressive systemic mastocytosis (ASM), systemic mastocytosis with an associated hematologic neoplasm (SM-AHN), and mast cell leukemia (MCL). Although not always present, mutations in KIT appear to result in uncontrolled growth of MCs. The KITD816V mutation is present in over 90% of mastocytosis patients. It is located in exon 17 in the intracellular tyrosine kinase 2 (TK2) domain. This mutation, as well as expression of either CD2 or CD25 (confirmed by immunostaining or flow cytometry), are characteristic of primary clonal/monoclonal mast cell activation syndrome (CMCAS/MMAS).
Further complicating the diagnosis is the fact that many patients with Parkinson's disease will have major depressive disorder, which may be the underlying cause of catatonia. Parkinson's disease can be distinguished from catatonia by a positive response to levodopa. Catatonia, on the other hand, will show a positive response to benzodiazepines. Extrapyramidal side effects of antipsychotic medication, especially dystonia and akathisia, can be difficult to distinguish from catatonic symptoms, or may confound them in the psychiatric setting. Extrapyramidal motor disorders usually do not involve social symptoms like negativism, while individuals with catatonic excitement typically do not have the physically painful compulsion to move that is seen in akathisia. Certain stimming behaviors and stress responses in individuals with autism spectrum disorders can present similarly to catatonia. In autism spectrum disorders, chronic catatonia is distinguished by a lasting deterioration of adaptive skills from the background of pre-existing autistic symptomatology that cannot be easily explained. Acute catatonia is usually clearly distinguishable from autistic symptoms. The diagnostic entities of obsessional slowness and psychogenic parkinsonism show overlapping features with catatonia, such as motor slowness, gegenhalten (oppositional paratonia), mannerisms, and reduced or absent speech. However, psychogenic parkinsonism involves tremor which is unusual in catatonia.
Fourth, and more debated, article 24 requires that the longer an EU citizen stays in a host state, the more rights they have to access public and welfare services, on the basis of equal treatment. This reflects general principles of equal treatment and citizenship in TFEU articles 18 and 20. In a simple case, in Sala v Freistaat Bayern the Court of Justice held that a Spanish lady who had lived in Germany for 25 years and had a baby was entitled to child support, without the need for a residence permit, because Germans did not need one. In Trojani v Centre public d'aide sociale de Bruxelles, a French man who lived in Belgium for two years was entitled to the "minimex" allowance from the state for a minimum living wage. In Grzelczyk v Centre Public d'Aide Sociale d'Ottignes-Louvain-la-Neuve a French student, who had lived in Belgium for three years, was entitled to receive the "minimex" income support for his fourth year of study. Similarly, in R (Bidar) v London Borough of Ealing the Court of Justice held that it was lawful to require a French UCL economics student lived in the UK for three years before receiving a student loan, but not that he had to have additional "settled status". Similarly, in Commission v Austria, Austria was not entitled to restrict its university places to Austrian students to avoid "structural, staffing and financial problems" if (mainly German) foreign students applied, unless it proved there was an actual problem.
== External links == Histology image: 14805loa – Histology Learning System at Boston University Anatomy photo: Reproductive/mammal/ovary2/ovary5 - Comparative Organology at University of California, Davis - "Mammal, canine ovary (LM, High)" Anatomy photo: Reproductive/mammal/ovary5/ovary6 - Comparative Organology at University of California, Davis - "Mammal, bovine ovary (LM, Medium)" Anatomy Atlases – Microscopic Anatomy, plate 13.249 Slide at trinity.edu
Sources: en.wikipedia.org
Anti-doping and clinical laboratories commonly use liquid chromatography-tandem mass spectrometry. The method can identify GW501516 and its metabolites in urine or blood. Detection depends on sample timing and the amount present.
PPARδ is a nuclear receptor that regulates genes linked to fatty acid oxidation and energy metabolism. Activation can alter lipid handling and energy use in experimental models. The full range of effects in humans is still under study.
The solid compound is generally stable when kept cold, dry, and protected from light. Solutions may degrade faster, so laboratory protocols often specify fresh preparation or cold storage. Stability can depend on solvent, concentration, and container.
Cardarine is a common name for GW501516, a synthetic PPARδ agonist. It is not a steroid or a selective androgen receptor modulator. It was developed and studied as a research compound for metabolic pathways.