The short version of Anti-doping testing fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
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.
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.
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
Cardarine is not approved for human therapeutic use in any major jurisdiction. It appears on the World Anti-Doping Agency Prohibited List as a PPARδ agonist within the hormone and metabolic modulators category. Sports organizations test for it because it has been detected in athlete samples and seized products. Regulatory actions against marketed research chemical versions have occurred in several countries, though enforcement varies. Availability through unregulated channels complicates oversight.
Analytical laboratories typically identify cardarine and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is a common matrix in anti-doping testing, while blood and tissue may be used in research settings. Detection windows depend on the assay, the sample matrix, and the compound's metabolism. Because cardarine is extensively metabolized, laboratories often target specific metabolites to improve sensitivity and confirmation. Reference standards are required for reliable quantification. Method validation includes checks for selectivity, linearity, and carryover.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic PPARδ agonist | Not a steroid or a selective androgen receptor modulator. |
| Common synonyms | Cardarine, GW501516, GW-501516, endurobol | Names vary by supplier and literature source. |
| Appearance | White to off-white powder | Consistent with many small-molecule research chemicals. |
| Solubility | Low in water; soluble in DMSO and ethanol | Often prepared in organic solvent for laboratory work. |
| Primary target | PPARδ (NR1C2) | Nuclear receptor involved in lipid and energy metabolism. |
==== Core ==== There is some dispute about the origin of the fluorescent chromophore core. Originally, it was widely thought to be synthesized by the pvcABCD operon, as deletion of portions of the pvcC and pvcD genes disrupts pyoverdine production. Like other aspects of pyoverdine biosynthesis, the regulation of the pvcABCD is iron-dependent, and the loss of these genes' activity resulted in pyoverdine disruption. A separate report suggests that pvcABCD may be responsible for the synthesis of paerucumarin (a pseudoverdine-related molecule) instead, and claims that loss of activity in the locus has no effect on pyoverdine production. In addition, some fluorescent Pseudomonads lack apparent homologs of these genes, further calling into question whether this is the function of these genes. This is consistent with reports that pvdL combines coenzyme A to a myristic acid moiety, then adds a glutamate, D-tyrosine, and L-2,4-diaminobutyric acid (DAB). An alternate biosynthetic pathway suggests that pvdL incorporates glutamate, 2,4,5-trihydroxyphenylalanine and L-2,4-diaminobutyric acid instead. This latter is supported by the identification of incorporation of a radiolabeled tyrosine into either pyoverdine or pseudoverdine. This discrepancy remains unresolved.
== Medical uses == Phenibut is used in Russia, Ukraine, Belarus and Latvia as a pharmaceutical drug to treat anxiety and to improve sleep (e.g., in the treatment of insomnia). It is also used for various other indications, including the treatment of asthenia, depression, alcoholism, alcohol withdrawal syndrome, post-traumatic stress disorder, stuttering, tics, vestibular disorders, Ménière's disease, dizziness, for the prevention of motion sickness, and for the prevention of anxiety before or after surgical procedures or painful diagnostic tests.
== Medical uses == Velmanase alfa is indicated for the treatment of the non-central nervous system manifestations of alpha-mannosidosis. Alpha-mannosidosis is a rare genetic lysosomal storage disorder. The symptoms of the disorder vary, but often include mild to moderate intellectual disability, hearing loss, weakened immune system, distinctive facial features (e.g., a large head, prominent forehead, and protruding jaw), skeletal abnormalities, and muscle weakness. Alpha-mannosidosis is caused by genetic changes in the MAN2B1 gene, which codes for the lysosomal alpha-mannosidase enzyme. Mutations of the MAN2B1 gene result in the lack of production of the alpha-D-mannosidase enzyme or the production of a defective, inactive form of the enzyme. Alpha-mannosidosis affects about 1 in every 500,000 people worldwide.
== Advantages and disadvantages == BV provides a good measure of the usability of proteins in a diet and also plays a valuable role in detection of some metabolic diseases. BV is, however, a scientific variable determined under very strict and unnatural conditions. It is not a test designed to evaluate the usability of proteins whilst an organism is in everyday life — indeed the BV of a diet will vary greatly depending on age, weight, health, sex, recent diet, current metabolism, etc. of the organism. In addition BV of the same food varies significantly species to species. Given these limitations BV is still relevant to everyday diet to some extent. No matter the individual or their conditions a protein source with high BV, such as egg, will always be more easily used than a protein source with low BV.
Gallium nitrate is used to treat the side effects of cancer; gallium citrate, a radiopharmaceutical, facilitates imaging of inflamed body areas. Selenium sulfide is used in medicinal shampoos and to treat skin infections such as tinea versicolor. Iodine is used as a disinfectant in various forms. Bismuth is an ingredient in some antibacterials.
Sources: en.wikipedia.org
=== Mid-cycle === The absence of GnSAF lowers the threshold for GnRH pulse frequency and amplitude required to stimulate the anterior pituitary to secrete LH. Concurrently, GnRH pulse frequency and amplitude increases, which allows LH secretion significantly higher than basal levels. The LH secretion most noticeable as a LH surge lasting 48 to 72 hours in the middle of the ovarian cycle. Meiosis in the dominant follicle resumes and follicle ruptures shortly after the LH surge. Ovulation can only occur if GnSAF is absent and the mid-cycle LH surge occurs.
== Ligand selection == Ligands are molecules responsible for binding to receptors in the cellular targeting process. Surface-coupled ligands offer a greater degree of freedom to move on the liposome membrane for optimal interactions. Ligands are typically monoclonal antibodies (mAbs) or antibody fragments, but can also include other molecules such as ARPG, proteins, peptides, vitamins, carbohydrates, and glycoproteins. The choice of ligand can significantly influence the behavioral and functional properties of a ligand-targeted liposome. Antibody fragments have lower immunogenicity and improved pharmacokinetics. mAbs are unique and can be used for inhibition of DNA repair, terminating the cell cycle, and triggering apoptosis, all of which factor into applications for anticancer drugs. Peptides are relatively easy and affordable to prepare with low antigenicity and lower opsonization, which are thus more resistant to enzymatic degradation. Proteins can target the transferrin receptor membrane glycoprotein. Sugars and vitamins are recognized by cellular transport receptors. Ligand choice is based on receptor expression, ligand internalization, binding affinity, and type of ligand. Ligands alone are not able to carry an efficient payload for therapeutic levels but can carry more of the agent when combined with liposomes.
In the 1980s, RNA structures capable of self-processing were discovered, with the RNA moiety of ribonuclease P acting as its catalytic subunit. These catalytic RNAs – referred to as RNA enzymes, or ribozymes – are found in today's DNA-based life and could be examples of living fossils. Ribozymes play vital roles, such as that of the ribosome. The large subunit of the ribosome includes an rRNA responsible for the peptide bond-forming peptidyl transferase activity of protein synthesis. Many other ribozyme activities exist; for example, the hammerhead ribozyme performs self-cleavage and an RNA polymerase ribozyme can synthesize a short RNA strand from a primed RNA template. Among the enzymatic properties important for the beginning of life are:
Aside from the 22 proteinogenic amino acids, many non-proteinogenic amino acids are known. These either are not found in proteins (for example carnitine, GABA, ornithine) or are not produced directly and in isolation by standard cellular machinery. For example, hydroxyproline is synthesized from proline, and selenomethionine is produced by metabolic modification of methionine. Non-proteinogenic amino acids that are found in proteins are formed by post-translational modification. Such modifications can also determine the localization of the protein, e.g., the addition of long hydrophobic groups can cause a protein to bind to a phospholipid membrane. Examples:
=== Weissenbacher-Zweymüller syndrome === At least one identified mutation in the COL11A2 gene is responsible for Weissenbacher-Zweymüller syndrome. This mutation causes the amino acid glycine to be replaced with the amino acid glutamic acid at position 955 in the alpha 2 chain of type XI collagen (written as Gly955Glu). This mutation prevents collagen molecules from being assembled properly, which disrupts the structure of type XI collagen. These changes result in the characteristic signs and symptoms of Weissenbacher-Zweymüller syndrome.
Sources: en.wikipedia.org
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.
It binds to and activates PPARδ, a nuclear receptor that regulates genes related to fatty acid oxidation and energy use. This activation alters transcription in tissues such as skeletal muscle and liver. The full range of downstream effects in humans is not fully established.
No, cardarine is not known to occur naturally in plants, animals, or humans. It is a synthetic molecule produced for laboratory research. Products labeled as cardarine should therefore be treated as manufactured chemicals with variable purity.
No. Cardarine has not received approval for human therapeutic use in major jurisdictions. It remains an investigational compound.