The short version of PPARδ fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
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.
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.
GW501516 acts as a selective agonist at PPARδ, a nuclear receptor that regulates transcription of genes involved in lipid handling and energy metabolism. Activation of PPARδ in preclinical models increases fatty acid oxidation, mitochondrial biogenesis, and exercise endurance in rodents. These effects have made the compound a subject of metabolic research and also a target for sport anti-doping rules. In humans, however, controlled studies are limited, and whether similar endurance or metabolic changes occur at tolerated exposures remains an open question. The receptor’s broad tissue distribution also means downstream effects may vary by organ and condition.
| Property | Value | Notes |
|---|---|---|
| IUPAC name | {4-[({4-methyl-2-[4-(trifluoromethyl)phenyl]-1,3-thiazol-5-yl}methyl)sulfanyl]phenoxy}acetic acid | Systematic name for GW501516 |
| CAS Registry Number | 317318-70-0 | Unique identifier for the parent compound |
| Molecular formula | C21H18F3NO3S2 | Includes carbon, hydrogen, fluorine, nitrogen, oxygen, and sulfur |
| Molecular weight | 453.5 g/mol | Approximate value for the neutral form |
| Appearance | White to off-white powder | Typical description for purified laboratory material |
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.
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.
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.
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.
==== Absorption ==== The total absorption of ramelteon is 84% while its oral bioavailability is 1.8%. The low bioavailability of ramelteon is due to extensive first-pass metabolism. Ramelteon has a higher lipophilicity than melatonin and thus permeates more easily into tissue. The absorption of ramelteon is rapid, with peak levels being reached after approximately 0.75 hours (range 0.5–1.5 hours). Food increases peak concentrations of ramelteon by 22% and overall exposure by 31% and delays the time to peak levels by approximately 0.75 hours. The pharmacokinetics of ramelteon are linear across a dose range of 4 to 64 mg. There is substantial interindividual variability in the peak concentrations and area-under-the-curve levels of ramelteon which is consistent with high first-pass metabolism.
In one small study, a significant increase in alpha-defensin levels was detected in T cell lysates of schizophrenia patients; in discordant twin pairs, unaffected twins also had an increase, although not as high as that of their ill siblings. The Virtual Colony Count antibacterial assay was originally developed to measure the activity of all six human alpha defensins on the same microplate.
John Ternus is chosen as Apple's next CEO, effective September 1, 2026. FBI Director Kash Patel sues The Atlantic in a $250 million defamation lawsuit over an article claiming that Patel is an alcoholic. April 21 Trump says that he extended the Iran truce to allow time for an Iranian proposal to be submitted at Pakistan's request. 2026 Virginia redistricting amendment: Voters in Virginia approve a redistricting referendum aimed at boosting Democrats' chance of winning seats in the upcoming midterms. The DOJ charges the Southern Poverty Law Center with defrauding donors with payments to white nationalist informants. April 22 – A chemical accident in Institute, West Virginia leaves two dead and 30 others injured. April 23 Trump orders the US Navy to destroy any Iranian boats laying mines in the Strait of Hormuz. Acting Attorney General Blanche reclassifies marijuana to a Schedule III drug. Warner Bros. Discovery shareholders approve Paramount Skydance's proposed acquisition of the company in a deal valued at $111 billion including debt, moving the merger a step closer to completion pending regulatory approval. A shooting at the Mall of Louisiana in Baton Rouge leaves five injured and one dead. April 24 – Trump fires all 24 members of the National Science Board, the body that oversees the National Science Foundation.
Biopharmaceuticals may be produced from microbial cells (e.g., recombinant E. coli or yeast cultures), mammalian cell lines (see Cell culture) and plant cell cultures (see Plant tissue culture) and moss plants in bioreactors of various configurations, including photo-bioreactors. Important issues of concern are cost of production (low-volume, high-purity products are desirable) and microbial contamination (by bacteria, viruses, mycoplasma). Alternative platforms of production which are being tested include whole plants (plant-made pharmaceuticals).
Sources: en.wikipedia.org
==== Experimental analogues ==== Insulin tregopil is an experimental ultra-fast-acting insulin that is being developed by Biocon. Unlike other insulin analogues, it is designed to be taken orally. It has been modified with the covalent attachment of a methoxy-triethylene-glycol-propionyl moiety at Lys-β29-amino group of the B-chain. This modification, along with the use of sodium caprate as a permeation enhancer, allows insulin tregopil to be absorbed through the gastrointestinal tract. Another oral analogue called ORMD-0801 is, as of 2025, in development by Oramed Pharmaceuticals. Insulin efsitora alfa is an experimental insulin analogue developed by Eli Lilly for the treatment of diabetes. Its glycemic control and safety were found to be similar to insulin degludec in a phase II clinical trial. NNC2215 is a bioengineered glucose-sensitive insulin analogue developed by Novo Nordisk researchers. The drug is designed to adjust its activity based on blood glucose levels, reducing insulin sensitivity when glucose concentrations are low, thereby lowering the risk of hypoglycemia. It also provides more stable blood sugar control by responding dynamically to fluctuations in glucose levels. A study on NNC2215 was published in the journal Nature on 16 October 2024, describing its potential as a major advancement in diabetes treatment and the role of protein engineering in future medicine. The development of glucose-sensitive insulin has been an area of interest in diabetes research since 1979, aiming to address blood sugar fluctuations.
Medvedev said that if he had not ordered the Russian forces to stop, "Georgia would most likely have a different president by now." On 21 November 2011, Dmitry Medvedev told reporters in Rostov-on-Don, "We have simply calmed some of our neighbors down by showing them that they should behave correctly in respect of Russia and in respect of neighboring small states." He also said that the war was a message to the NATO that "before taking a decision about expansion of the Alliance, one should at first think about the geopolitical stability." On 8 August 2012, Russian Prime Minister Dmitry Medvedev said: "I made my decision two-and-a-half hours after the Georgian army began the active fighting. Not earlier, because this would have been wrong, since this was the decision to use the Armed Forces of the Russian Federation on foreign soil, I underline, the foreign territory. But not later too." He also said that he contacted Putin on 8 August. On 8 August 2012, Russian president Vladimir Putin told journalists that Russia had a plan for the war with Georgia in advance before the hostilities and it was prepared by the Russian General Staff in late 2006-early 2007. According to Putin, he oversaw the plan, which included training of South Ossetian militia. Putin commented on his personal role, "While in Beijing, I called Dmitry Medvedev and the defense minister twice, on August 7 and 8." Putin later said, "The information what was happening at the time of the 5th, 6th, 7th and 8th of the (August 2008), I received directly from Tskhinvali. Oddly enough, from journalists.
== In platelets == The alpha granules in blood platelets contain growth factors PDGF, IGF-1, EGF, and TGF-β which begin healing of wounds by attracting and activating macrophages, fibroblasts, and endothelial cells.
=== Soviet disintegration === Political scientist Alex Pravda frames the Soviet collapse as unfolding in two acts: an initial phase, from 1989 to 1990, driven by smaller republics in the Baltic and Caucasus seeking sovereignty, followed by a second, from late 1990 through 1991, in which the defection of larger republics—Ukraine and, decisively, Russia under Boris Yeltsin—eroded the center's capacity to hold the union together. For Pravda, the USSR's demise was overwhelmingly domestic in origin, driven by ethnic nationalist movements that flourished under perestroika's liberalized conditions and were seized upon by republican elites contesting a Kremlin weakened by economic crisis; the international dimension of the Cold War's end played, in his assessment, only a secondary role. The collapse of the Eastern European governments with Gorbachev's tacit consent inadvertently encouraged several Soviet republics to seek greater independence from Moscow's rule. Agitation for independence in the Baltic states led to first Lithuania, and then Estonia and Latvia, declaring their independence. Disaffection in the other republics was met by promises of greater decentralization. More open ballots led to the election of candidates opposed to the Communist Party of the Soviet Union, but it also contributed to party fragmentation and presidentialism, which complicated democratic transition. Washington's confidence in the Soviet Union's survival outlasted Moscow's own. Visiting Kiev on 1 August 1991, George Bush Sr.
== Benefits == One of the main advantages of this method of preparing frozen food is that the freezing process takes only a few minutes. The exact time depends on the type of IQF freezer and the product. The short freezing prevents formation of large ice crystals in the product's cells, which destroys the membrane structures at the molecular level. This makes the product keep its shape, colour, smell and taste after defrost, to a far greater extent. Another advantage of IQF technology is its ability to separate units of the products during freezing, which produces a higher quality product compared to block freezing. This is important for food sustainability, as the consumer can defrost and use the exact quantity needed. A growing demand in IQF products is registered at global level due to the higher quality of these products and to the benefit of having separately frozen pieces. IQF is also a common pre-treatment for freeze-drying food because both processes preserve the size, taste and cell structure of the food better than methods such as traditional block freezing or air drying.
Sources: en.wikipedia.org
=== Proton pumps === A proton pump is any process that creates a proton gradient across a membrane. Protons can be physically moved across a membrane, as seen in mitochondrial Complexes I and IV. The same effect can be produced by moving electrons in the opposite direction. The result is the disappearance of a proton from the cytoplasm and the appearance of a proton in the periplasm. Mitochondrial Complex III is this second type of proton pump, which is mediated by a quinone (the Q cycle). Some dehydrogenases are proton pumps, while others are not. Most oxidases and reductases are proton pumps, but some are not. Cytochrome bc1 is a proton pump found in many, but not all, bacteria (not in E. coli). As the name implies, bacterial bc1 is similar to mitochondrial bc1 (Complex III).
=== Homonuclear nuclear magnetic resonance === With unlabelled protein the usual procedure is to record a set of two-dimensional homonuclear nuclear magnetic resonance experiments through correlation spectroscopy (COSY), of which several types include conventional correlation spectroscopy, total correlation spectroscopy (TOCSY) and nuclear Overhauser effect spectroscopy (NOESY). A two-dimensional nuclear magnetic resonance experiment produces a two-dimensional spectrum. The units of both axes are chemical shifts. The COSY and TOCSY transfer magnetization through the chemical bonds between adjacent protons. The conventional correlation spectroscopy experiment is only able to transfer magnetization between protons on adjacent atoms, whereas in the total correlation spectroscopy experiment the protons are able to relay the magnetization, so it is transferred among all the protons that are connected by adjacent atoms. Thus in a conventional correlation spectroscopy, an alpha proton transfers magnetization to the beta protons, the beta protons transfers to the alpha and gamma protons, if any are present, then the gamma proton transfers to the beta and the delta protons, and the process continues. In total correlation spectroscopy, the alpha and all the other protons are able to transfer magnetization to the beta, gamma, delta, epsilon if they are connected by a continuous chain of protons. The continuous chain of protons are the sidechain of the individual amino acids.
== Use as a biomarker == Dinosterol is used as a biomarker for organic matter derived from dinoflagellates in sediments and seawater. Biomarkers are organic compounds that are indicative of former life in sediments, seawater and oil. The presence of the saturated hydrocarbon counterpart, dinosterane, is used as evidence that some of the organic matter present in ancient sediments may have been derived from dinoflagellates.
Cyanophycinase (EC 3.4.15.6, cyanophycin degrading enzyme, beta-Asp-Arg hydrolysing enzyme, CGPase, CphB, CphE, cyanophycin granule polypeptidase, extracellular CGPase) is an enzyme. It catalyses the following chemical reaction
Sources: en.wikipedia.org
No. Major drug regulators have not approved GW501516 for treating any medical condition. Products sold as cardarine are typically unapproved research chemicals or supplements, so their contents and safety are not assured.
It is prohibited by the World Anti-Doping Agency as a hormone and metabolic modulator. Athletes who test positive for GW501516 can face sanctions, including suspensions and loss of results.
Cardarine is a common or trade-style name, while GW501516 is the research code for the same chemical entity. Some sources also use Endurobol or GSK-516. The names refer to the same compound, not distinct drugs.
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.