A practical reference on GW501516: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-11-11. Anything still debated is marked as such rather than presented as settled.
Cardarine is a common name for GW501516, a synthetic compound developed in the 1990s through research collaborations involving GlaxoSmithKline. It belongs to a class of molecules known as peroxisome proliferator-activated receptor delta agonists. Early studies explored its effects on lipid metabolism and energy expenditure in animal models. The compound was never approved as a human medicine, and clinical development was discontinued. In the years since, it has appeared in fitness and bodybuilding communities as a performance-enhancing substance. Regulatory agencies classify it as an unapproved drug.
PPARδ is a nuclear receptor that regulates gene expression related to fatty acid oxidation, glucose homeostasis, and mitochondrial function. GW501516 binds to this receptor with high affinity and activates downstream signaling in skeletal muscle and other tissues. Animal studies reported increased endurance and altered fuel preference, but human data remain limited and inconsistent. The precise relationship between receptor activation and observed physiological changes is still an area of active investigation. Researchers have also examined whether the compound affects inflammation or cell proliferation. No approved therapeutic indication exists for cardarine.
In laboratory settings, cardarine is studied as a tool compound for probing PPARδ biology. Published experiments often use cell cultures, rodent models, or isolated tissues. Some investigations focus on metabolic effects, while others assess potential risks such as carcinogenicity observed in long-term animal studies. Because human trials are sparse, most knowledge comes from preclinical work and adverse event reports. Scientific literature frequently notes the gap between animal findings and human outcomes. The compound is not a dietary supplement and is not intended for human consumption.
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.
| Property | Value | Notes |
|---|---|---|
| CAS Registry Number | 317318-70-0 | Unique identifier for the compound. |
| Chemical class | PPARδ agonist | Synthetic ligand for peroxisome proliferator-activated receptor delta. |
| Appearance | White to off-white solid | Typical form of research-grade material. |
| Solubility | Soluble in DMSO and ethanol | Poorly soluble in water. |
| Typical storage | -20°C | Recommended for long-term storage of stock solutions. |
Anti-doping laboratories identify GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the usual matrix, and detection can occur after the parent compound has cleared from blood. The exact detection window depends on dose, formulation, individual metabolism, and assay sensitivity. Because the compound is prohibited at all times, athletes are subject to testing in and out of competition. Analytical methods continue to improve as new metabolites and designer analogs are characterized.
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.
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.
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 is a common name for GW501516, a synthetic compound first described in the 1990s as a selective agonist of the peroxisome proliferator-activated receptor delta. It was studied in preclinical models for metabolic and cardiovascular conditions, but it has not been approved as a medicine in the United States, Europe, or other major jurisdictions. Retail products labeled as cardarine are generally research chemicals or supplements, not pharmaceutical formulations. Because human safety and efficacy data remain limited, regulatory agencies treat it as an unapproved substance rather than a therapeutic product.
Sporting authorities added GW501516 to prohibited lists after it appeared in athlete samples and online markets. The World Anti-Doping Agency classifies it as a hormone and metabolic modulator, and its use can lead to an anti-doping rule violation. Some early laboratory work suggested effects on fatty acid oxidation and endurance-related metabolism in animals, but those findings do not establish safe or effective use in people. Reports of adverse events in humans are scarce and often anecdotal, which complicates risk assessment.
Finally, the Safety and Health at Work Directive 1989 requires basic requirements to prevent and insure against workplace risks, with employee consultation and participation, and this is complemented by specialised Directives, ranging from work equipment to dangerous industries. In almost all cases, all member states go significantly beyond this minimum. The objective of transnational regulation is therefore to progressively raise the minimum floor in line with economic development. Second, equality was affirmed by the Court of Justice in Kücükdeveci v Swedex GmbH & Co KG to be a general principle of EU law. Further to this, the Part-time Work Directive 1997, Fixed-term Work Directive 1999 and Temporary Agency Work Directive 2008 generally require that people who do not have ordinary full-time, permanent contracts are treated no less favourably than their colleagues. However, the scope of the protected worker is left to member state law, and the TAWD 2008 only applies to "basic working conditions" (mostly pay, working hours and participation rights) and enabled member states to have a qualifying period. The Race Equality Directive 2000, Equality Framework Directive 2000 and Equal Treatment Directive 2006 prohibit discrimination based on sexual orientation, disability, religion or belief, age, race and gender. As well as "direct discrimination", there is a prohibition on "indirect discrimination" where employers apply a neutral rule to everybody, but this has a disproportionate impact on the protected group.
Lula stated during the 2022 election campaign and after taking office that his government will consistently focus on to "bring back Brazil to the world stage", meaning the country will seek to rebuild ties cut or damaged during Bolsonaro's presidency, and expand its foreign relations worldwide. On 9 December 2022 Lula announced that to head the Ministry of Foreign Affairs (Itamaraty) he had chosen Brazilian ambassador, career diplomat and former foreign minister Mauro Vieira. As an effort to empower women diplomats, he picked ambassador and career diplomat Maria Laura da Rocha as Itamaraty's deputy foreign minister and Maria Luiza Ribeiro Viotti as Brazil's ambassador to the US, both the first women to ever hold those positions. More women are also expected to be appointed to top positions.
== External links == Controlled vocabulary of post-translational modifications in Uniprot List of posttranslational modifications in ExPASy Browse SCOP domains by PTM — from the dcGO database Overview and description of commonly used post-translational modification detection techniques
== Causes == The Jarisch–Herxheimer reaction is traditionally associated with antimicrobial treatment of syphilis. The reaction is also seen in the other diseases caused by spirochetes: Lyme disease, relapsing fever, and leptospirosis. There have been case reports of the Jarisch–Herxheimer reaction accompanying treatment of other infections, including Q fever, bartonellosis, brucellosis, trichinellosis, and African trypanosomiasis.
Sources: en.wikipedia.org
By 2011, CRE was reported in at least 22 countries. Between 2009 and 2012, 10 cases of CRE infections were documented in ICU patients in a Melbourne, Australia, hospital. Some cases of CRE are associated with receipt of medical care in the US. Strains found in Israel had genetic similarity to strains from the US. Hospital handwashing stations were found to be environmental reservoirs for CRE after screening all wet-area locations, including sinks, water fountains, and ice machines. The main reservoirs for CRE were the ICU sinks, and inappropriate cleaning methods accounted for transmission from sink to sink. The CRE strains in the sinks and the strains infecting the ICU patients were identical per genetic analysis. At-risk patients were being infected in the hospital setting. A study, conducted in 2016–2017 at a pediatric hospital in Kathmandu, Nepal, detected the presence of the blaNDM-1 gene among carbapenem-resistant Escherichia coli and Klebsiella pneumoniae isolates confirmed by the Modified Hodge Test, analyzing 1503 clinical samples collected over six months. Genetic analysis revealed that half of the E. coli and two-thirds of the K. pneumoniae carbapenemase-producing isolates carried the blaNDM-1 gene, highlighting the prevalence of this resistance mechanism in Nepal
=== Other species === FPR receptors are widely distributed throughout mammalian species with the FPR1, FPR2, and FPR3 paralogs, based on phylogenetic analysis, originating from a common ancestor, early duplication of FPR1, and FPR2/FPR3 splitting with FPR3 originating from the latest duplication event near the origin of primates. Rabbits express an ortholog of FPR1 (78% amino acid sequence identity) with high binding affinity for FMLP; rats express an ortholog of FPR2 (74% amino acid sequence identity) with high affinity for lipoxin A4.
== Paralogy == Paralogous genes are genes that are related via duplication events in the last common ancestor (LCA) of the species being compared. They result from the mutation of duplicated genes during separate speciation events. When descendants from the LCA share mutated homologs of the original duplicated genes then those genes are considered paralogs. As an example, in the LCA, one gene (gene A) may get duplicated to make a separate similar gene (gene B), those two genes will continue to get passed to subsequent generations. During speciation, one environment will favor a mutation in gene A (gene A1), producing a new species with genes A1 and B. Then in a separate speciation event, one environment will favor a mutation in gene B (gene B1) giving rise to a new species with genes A and B1. The descendants' genes A1 and B1 are paralogous to each other because they are homologs that are related via a duplication event in the last common ancestor of the two species. Additional classifications of paralogs include alloparalogs (out-paralogs) and symparalogs (in-paralogs). Alloparalogs are paralogs that evolved from gene duplications that preceded the given speciation event. In other words, alloparalogs are paralogs that evolved from duplication events that happened in the LCA of the organisms being compared. The example above is an example alloparalogy. Symparalogs are paralogs that evolved from gene duplication of paralogous genes in subsequent speciation events.
First the image is drawn out. Second asterisks are placed by potential stereocenters as indicators (*). Third the pairs of each stereocenters R and S orientations are combined through all possible permutations of stereocenters. Fourth the permutations are checked for super-imposability, indicating that they are varying around what is not a true stereocenter and therefore the permutations are truly the self-same stereoisomer. This procedure will be used when making an assessment of the number of valid stereoisomers that an analogue of fentanyl will be predicted to have. Because the analogues of fentanyl are so large, and the moieities (sub-regions) of the molecule that are relevant to its chirality are so small, that we often reproduce the fentanyl analogue as a smaller, simpler molecule with the same number of, and dynamics between its, stereocenters. This saves significant space allowing us not to reproduce redundant material that consumes a lot of space on the image. The first case studied here is fentanyl itself, or propionyl-4-anilino-N-phenethylpiperidine, the most well known of the fentanyl analogues and the eponymous molecule (namesake) for the whole chemical category. The only identified stereocenter is found at the 4-carbon, opposite the piperidine nitrogen but adjacent to the aniline nitrogen. This seems to be a stereocenter because of the apparent 4 unique substituents. We transfer this stereocenter to the equivalent molecule cyclohexanol, with an analogous apparent stereocenter.
germ cell Any cell that gives rise to the gametes of a sexually reproducing organism. Germ cells are the vessels for the genetic material which will ultimately be passed on to the organism's descendants and are usually distinguished from somatic cells, which are entirely separate from the germ line.
Sources: en.wikipedia.org
Originally this research on alternative forms of DNA was driven by the question of how life evolved on earth and why RNA and DNA were selected by (chemical) evolution over other possible nucleic acid structures. Two hypotheses for the selection of RNA and DNA as life's backbone are either they are favored under life on Earth's conditions, or they were coincidentally present in pre-life chemistry and continue to be used now. Systematic experimental studies aiming at the diversification of the chemical structure of nucleic acids have resulted in completely novel informational biopolymers. So far a number of XNAs with new chemical backbones or leaving group of the DNA have been synthesized, e.g.: hexose nucleic acid (HNA); threose nucleic acid (TNA), glycol nucleic acid (GNA) cyclohexenyl nucleic acid (CeNA). The incorporation of XNA in a plasmid, involving 3 HNA codons, has been accomplished already in 2003. This XNA is used in vivo (E coli) as template for DNA synthesis. This study, using a binary (G/T) genetic cassette and two non-DNA bases (Hx/U), was extended to CeNA, while GNA seems to be too alien at this moment for the natural biological system to be used as template for DNA synthesis. Extended bases using a natural DNA backbone could, likewise, be transliterated into natural DNA, although to a more limited extent. Aside being used as extensions to template DNA strands, XNA activity has been tested for use as genetic catalysts.
In North America, the 323 saloon became the Protegé, while the 323 hatchback kept its name. There, and in the Philippines, base (SE/DX), 4WD and top-line LX models were available. The 1990 base model has the SE name and uses the B8 1.8 L SOHC engine that has 16 valves and hydraulic lifters. In 1991, the base model name was changed to "DX". 4WD models existed for the 1990 and 1991 model years, with the SOHC engine and rear disc brakes. The LX version of the Protegé included a 1.8 L DOHC 16-valve BP engine producing 125 hp (93 kW; 127 PS). LX models also have power windows and door locks and 14-inch wheels. Vented front and solid rear disc brakes, larger front brakes, larger clutch, equal-length driveshafts, dual outlet muffler, body-color door handles and mirrors, fold-down rear center armrest, driver's vanity mirror, and larger stabilizer bars. A sunroof and 14-inch aluminum alloy wheels were options on LX models. The Protegé nameplate was also applied for 323 saloon in Brazil, which was really similar to the Canadian market specification. However, only a fuel injected 1.8 L SOHC engine was offered there. BG models that were assembled in New Zealand came with glass headlights instead of plastic, and a 240 km/h speedometer. In Thailand, the 323 saloon was initially offered in a single unnamed trim with a carbureted 1.6 L SOHC engine as the sole option. The facelifted model was divided into two levels: the 1.3i and 1.6i LX, and the better-equipped 1.6i GLX. All engines featured fuel injection, and the latter came with a 4-speed automatic transmission as an option.
==== Electroporation ==== Electroporation is a method that uses high voltage to create pores in the membranes of mammalian cells. By pulsing with electricity, local areas of the cell membrane transiently destabilize and DNA can then enter the cell. At appropriate field strengths, damage to the host cell in minimal. This technique can be used for both short-term and long-term transfectants. It is also effective with almost any tissue type and has displayed high levels of gene delivery with an increase in the distribution of cells expressing the DNA.
Having considered the data provided, and other relevant information available in scientific literature, the SCCS cannot conclude on the safety of the hydroxyapatite composed of rod–shaped nanoparticles for use in oral-care cosmetic products at the maximum concentrations and specifications given in this Opinion. This is because the available data/information is not sufficient to exclude concerns over the genotoxic potential of HAP-nano. The European Commission's Scientific Committee on Consumer Safety (SCCS) reissued an updated opinion in 2023, where it cleared rod-shaped nano hydroxyapatite of concerns regarding genotoxicity, allowing consumer products to contain concentrations of nano hydroxyapatite as high as 10% for toothpastes and 0.465% for mouthwashes. However, it warns of needle-shaped nano hydroxyapatite and of inhalation in spray products. It stated:
Sources: en.wikipedia.org
Cardarine is a common name for GW501516, a synthetic PPARδ agonist developed for research. It has not been approved as a medication in any country. It is classified as an unapproved drug and a prohibited substance in sport.
No. Cardarine is not an anabolic steroid; it belongs to a different chemical class that targets PPARδ. Steroids act primarily through androgen receptors, while cardarine acts through a nuclear receptor involved in metabolism.
Some rodent studies reported increased endurance and changes in fat metabolism after cardarine exposure. Long-term studies in animals also raised concerns about cancer in certain tissues. Human trial data are limited, so these findings cannot be directly translated to people.
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.