anti-doping raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-07-27 and is reviewed periodically as new material appears.
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.
Regulatory bodies treat GW501516 as a prohibited substance in competitive sport. The World Anti-Doping Agency added it to the prohibited list, and it falls under classes covering metabolic modulators and hormone-related agents. It is not approved by drug regulators for human use, and it is not a lawful dietary supplement. Products sold under the cardarine name may contain unlisted ingredients or different compounds. Because no approved product exists, quality and identity are not guaranteed by pharmaceutical manufacturing standards.
The pharmacological interest in cardarine centers on PPARδ activation and its downstream effects on lipid handling and mitochondrial function. In animal studies, PPARδ agonists have been associated with changes in exercise endurance and fatty acid utilization, though results vary by model and protocol. Human data remain sparse, and the absence of large controlled trials limits conclusions about efficacy. Researchers often describe the compound as a tool for probing PPARδ biology rather than a proven therapeutic agent.
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.
| Property | Value | Notes |
|---|---|---|
| Common name | Cardarine | Common internet and media name. |
| Research code | GW501516 | Also written GW-1516. |
| Drug class | PPARδ agonist | Not a selective androgen receptor modulator. |
| Development status | Discontinued | Clinical development halted after rodent cancer findings. |
| Regulatory status | Prohibited in sport | Listed by WADA; not approved as medicine. |
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
Anti-doping laboratories identify GW501516 and related metabolites using liquid chromatography coupled with tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be analyzed. The method targets the parent compound and phase I and phase II metabolites, which extend the detection window. Because the substance is prohibited at all times, athletes can be tested outside competition. Detection limits and windows depend on the assay, sample type, and individual metabolism.
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.
The idea of hexapods being 'terrestrial crustaceans' is relatively recent, coming from a 2005 molecular analysis study. A 2013 study restructured the relationships within Pancrustacea, and first proposed the name Allotriocarida. The most recent study of Allotriocarida in 2019 provides additional evidence suggesting that Hexapoda and Remipedia are likely more closely related to each other than to Cephalocarida or Branchiopoda. As of 2024, the existence of Allotriocarida as a monophyletic group within Pancrustacea is now much more widely accepted than the Atelocerata classification which dates back to the 19th century. This formerly-held belief was that hexapods and myriapods (centipedes, millipedes, etc.) are more closely related to each other than they are to the Multicrustacea, based on morphological similarities in their tracheae, but this proposition has been contradicted by the aforementioned modern molecular phylogenetic studies. The most recent understanding of Allotriocarida, as described in the 2019 study, can be seen in the cladogram below.
Biochemical differences between different organisms and humans are useful for drug development. For instance, penicillin kills bacteria by inhibiting the bacterial enzyme DD-transpeptidase, destroying the development of the bacterial cell wall and inducing cell death. Thus, the study of binding sites is relevant to many fields of research, including cancer mechanisms, drug formulation, and physiological regulation. The formulation of an inhibitor to mute a protein's function is a common form of pharmaceutical therapy.
The MEROPS protease database includes the following ten families of asparagine peptide lyases, which are included in 6 different clans of proteases. Proteolytic enzymes are classified into families based on sequence similarity. Each family includes proteolytic enzymes with homologous sequences and common catalytic type. Clans are groups of proteolytic enzymes families with related structures, where catalytic type is not conserved. *Not yet included in IUBMB recommendations. The ten different families of asparagine peptide lyases are distributed in three different types: Viral coat proteins Autotransporter proteins Intein-containing proteins There are five families of viral coat proteins (N1, N2, N8, N7 and N5), two families of autotransporter proteins (N6 and N4) and three families of intein-containing proteins (N9, N10 and N11).
The cell membranes of bacteria are rich in acidic phospholipids, such as phosphatidylglycerol and cardiolipin. In contrast, the outer part of the membranes of plants and mammals is mainly composed of lipids without any net charges since most of the lipids with negatively charged headgroups are principally sequestered into the inner leaflet of the plasma membranes. Thus in the case of mammalian cells, the outer surfaces of the membranes are usually made of zwitterionic phosphatidylcholine and sphingomyelin, even though a small portion of the membrane's outer surfaces contain some negatively charged gangliosides. Therefore, the hydrophobic interaction between the hydrophobic face of amphipathic antimicrobial peptides and the zwitterionic phospholipids on the cell surface of mammalian cell membranes plays a major role in the formation of peptide-cell binding. Dual polarisation interferometry has been used in vitro to study and quantify the association to headgroup, insertion into the bilayer, pore formation and eventual disruption of the membrane.
Sources: en.wikipedia.org
Skeletal anomalies aren't present at birth but develop in the individual and include delayed bone maturation, slender long tubular bones, and tall vertebral bodies. Joint hyper-mobility and increased risk of hip dislocation has been presented in individuals. Abnormal spinal curvature, either kyhoscholiosis or hyperlordosis, causing back pain can also be experienced from this disorder. Additional physical abnormalities include an abnormally short broad neck and thorax, square shoulders, flared shoulder blades, unusual curving of the 5th finger, and prominent heels can be seen in some children. In some cases, males have been reported to have impaired fertility due to the reduced production of sex hormones and hypospadias which is when the opening of the urethra is on the underside of the penis instead of the tip. In contrast, females are reported to have normal ovarian function with this disorder.
The carbon atom next to the carboxyl group is called the α–carbon. In proteinogenic amino acids, it bears the amine and the R group or side chain specific to each amino acid, as well as a hydrogen atom. With the exception of glycine, for which the side chain is also a hydrogen atom, the α–carbon is stereogenic. All chiral proteinogenic amino acids have the L configuration, and can therefore be referred to as L-amino acids. They are "left-handed" enantiomers, which refers to the stereoisomers of the alpha carbon. A few D-amino acids ("right-handed") have been found in nature, e.g., in bacterial envelopes, as a neuromodulator (D-serine), and in some antibiotics. Rarely, D-amino acid residues are found in proteins, and are converted from the L-amino acid as a post-translational modification.
The intense research for development of efficient chiral selectors has resulted in the synthesis of over 1400 CSPs and over 200 CSPs have been commercialized and available in the market. The most commonly employed chiral selectors are categorized and presented in the table. It is surprising to note that In 1980, there was no single chiral stationary phase available in the market for performing chiral chromatography. However, In late 1980s the subject of enantioselective chromatography attracted growing interest, particularly under the drive of the institution of Okamoto in Japan, the teams of Pirkle, and Armstrong in the US, Schurig and König in Germany, Lindner in Austria, and Francotte in Switzerland . The Polysaccharides, amylose and cellulose, form the most abundant chiral polymers on earth. These naturally occurring polysaccharides form basis for an important class of chiral selectors.
In addition to killing bacteria directly they have been demonstrated to have a number of immunomodulatory functions that may be involved in the clearance of infection, including the ability to alter host gene expression, act as chemokines and/or induce chemokine production, inhibiting lipopolysaccharide induced pro-inflammatory cytokine production, promoting wound healing, and modulating the responses of dendritic cells and cells of the adaptive immune response. Animal models indicate that host defense peptides are crucial for both prevention and clearance of infection. It appears as though many peptides initially isolated as and termed "antimicrobial peptides" have been shown to have more significant alternative functions in vivo (e.g. hepcidin). Dusquetide for example is an immunomodulator that acts through p62, a protein involved in toll like receptor based signalling of infection. The peptide is being examined in a Phase III clinical trial by Soligenix (SGNX) to ascertain if it can assist in repair of radiation-induced damage to oral mucosa arising during cancer radiotherapy of the head and neck.
Imaging technologies are often essential to medical diagnosis, and are typically the most complex equipment found in a hospital including: fluoroscopy, magnetic resonance imaging (MRI), nuclear medicine, positron emission tomography (PET), PET-CT scans, projection radiography such as X-rays and CT scans, tomography, ultrasound, optical microscopy, and electron microscopy. An implant is a kind of medical device made to replace and act as a missing biological structure (as compared with a transplant, which indicates transplanted biomedical tissue). The surface of implants that contact the body might be made of a biomedical material such as titanium, silicone or apatite depending on what is the most functional. In some cases, implants contain electronics, e.g. artificial pacemakers and cochlear implants. Some implants are bioactive, such as subcutaneous drug delivery devices in the form of implantable pills or drug-eluting stents.
Sources: en.wikipedia.org
Anne Ephrussi (born 15 September 1955 in Paris, France) is a French developmental and molecular biologist. Her research is focused on the study of post-transcriptional regulations such as mRNA localization and translation control in molecular biology as well as the establishment of polarity axes in cell and developmental biology. She is director of the EMBL International Centre for Advanced Training (EICAT) program at the European Molecular Biology Laboratory (EMBL) since 2005 and served as head of the Developmental Biology Unit from 2007 to 2021.
Similar structures include the 310 helix (i + 3 → i hydrogen bonding) and the π-helix (i + 5 → i hydrogen bonding). The α-helix can be described as a 3.613 helix, since the i + 4 spacing adds three more atoms to the H-bonded loop compared to the tighter 310 helix, and on average, 3.6 amino acids are involved in one ring of α-helix. The subscripts refer to the number of atoms (including the hydrogen) in the closed loop formed by the hydrogen bond.
AlphaFold's predicted structures are widely used in biological research, though the precise scale of that use is difficult to measure. More than 40% of protein-structure papers published in 2023 in Cell, Nature, and Science cited AlphaFold 2. A 2024 bibliometric analysis of the Web of Science database identified 1,680 peer-reviewed papers referencing AlphaFold published between January 2019 and May 2024. Measures of this kind rely on authors citing the AlphaFold papers when they use the tool, a convention encouraged but not enforced by the maintainers of the AlphaFold Protein Structure Database. Attempts to validate these counts against the full text of papers suggest that citations to foundational AlphaFold papers can both overstate and understate how widely the tool is used. In an analysis of about 8,900 papers in the PubMed Central Open Access corpus that mentioned AlphaFold, roughly 30% cited none of three foundational AlphaFold papers, while only about half of the papers citing at least one of those three mentioned AlphaFold anywhere in their text. A smaller manual check of 100 papers from a curated protein-literature database found a similar shortfall, with fewer than half of those mentioning AlphaFold including a formal citation.
An antibody–drug conjugate consists of three components: Antibody - targets the cancer cell surface and may also elicit a therapeutic response. Payload - elicits the desired therapeutic response. Linker - attaches the payload to the antibody and should be stable in circulation only releasing the payload at the desired target. Multiple approaches to conjugation have been developed for attachment to the antibody and reviewed. DAR is the drug to antibody ratio and indicates the level of loading of the payload on the ADC.
The BtuCD and HI1470/1 are classified as large (Type II) ABC importers. The transmembrane subunit of the vitamin B12 importer, BtuCD, contains 10 TM helices and the functional unit consists of two copies each of the nucleotide binding domain (NBD) and transmembrane domain (TMD). The TMD and NBD interact with one another via the cytoplasmic loop between two TM helices and the Q loop in the ABC. In the absence of nucleotide, the two ABC domains are folded and the dimer interface is open. A comparison of the structures with (BtuCDF) and without (BtuCD) binding protein reveals that BtuCD has an opening that faces the periplasm whereas in BtuCDF, the outward-facing conformation is closed to both sides of the membrane. The structures of BtuCD and the BtuCD homolog, HI1470/1, represent two different conformational states of an ABC transporter. The predicted translocation pathway in BtuCD is open to the periplasm and closed at the cytoplasmic side of the membrane while that of HI1470/1 faces the opposite direction and open only to the cytoplasm. The difference in the structures is a 9° twist of one TM subunit relative to the other.
Sources: en.wikipedia.org
No. Cardarine is a PPARδ agonist, while selective androgen receptor modulators act on androgen receptors. The two classes differ in receptor target and downstream effects.
Preclinical rodent studies reported cancers, including liver and bladder tumors, at tested doses. The human relevance of those findings is uncertain, but development was discontinued. No approved human product resulted.
No. It remains an investigational compound without approved therapeutic labeling. Sports regulators prohibit its use, and health agencies have warned against consuming it.
Cardarine is an investigational synthetic compound that acts as a PPARδ agonist. It is also known as GW501516 and has been studied mainly in preclinical research. It is not an approved medicine.