Research chemical 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 2026-02-18 and is reviewed periodically as new material appears.
Regulatory treatment varies, but cardarine is not approved as a medicine. Sports authorities list GW501516 as a prohibited substance, and it is banned at all times under the World Anti-Doping Agency code. Many countries restrict sales for human consumption, while online vendors market it as a research chemical. Such products may lack purity data, and their actual contents can differ from the label. Purchasing or possessing cardarine may carry legal consequences depending on jurisdiction. The compound is not a dietary supplement ingredient in regulated markets.
Clinical development stopped after rodent studies showed tumors at multiple sites. Whether those findings predict human cancer risk remains an open question, but they led sponsors to discontinue programs. Human safety data are limited to small, short-term studies that were not designed to assess cancer risk. Reported effects in those studies included changes in blood lipids, but the evidence is insufficient for medical use. Long-term consequences of nonmedical use are not well characterized. Questions about dose, duration, and individual susceptibility remain unresolved.
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.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | GW501516; GW-1516; endurobol | GW501516 is the research code |
| Drug class | PPARδ agonist | Not a selective androgen receptor modulator |
| Molecular formula | C21H18F3NO3S2 | Established chemical formula |
| Molar mass | 453.5 g/mol | Calculated from the formula |
| Regulatory status | Prohibited in sport; not approved as medicine | Status varies by country |
Because cardarine is not an approved medicine, no pharmacopeial monograph defines its identity, purity, or storage requirements. Laboratories typically rely on in-house methods and reference standards when testing materials labeled as GW501516. Certificates of analysis may report purity and identity for a specific batch, but their scope varies and they do not guarantee safety or legal status. Independent verification can include high-performance liquid chromatography, mass spectrometry, nuclear magnetic resonance, and elemental analysis. The distinction between research chemical labeling and human use is significant because quality standards and oversight differ.
Cardarine can be detected in biological samples and product materials using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method separates compounds by chromatography and identifies them by mass-to-charge transitions, allowing low-level detection in urine or blood. Sample preparation often involves enzymatic hydrolysis, solid-phase extraction, or protein precipitation. Certified reference materials and isotope-labeled internal standards improve quantification. Detection windows depend on metabolism, matrix, and assay sensitivity, so no single universal window applies.
In the fitness and bodybuilding literature, cardarine is frequently discussed as an endurance agent or fat-loss compound, although such claims are not supported by robust clinical evidence. Online descriptions often mix animal data, user anecdotes, and marketing language. Researchers who study PPARδ agonists distinguish between receptor activation in controlled experiments and unsupervised use of unverified products. The latter introduces unknown purity, dose, and interactions, making reported experiences difficult to interpret scientifically.
GW501516 acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in transcription of genes related to lipid handling and energy use. Activation of PPARδ can shift skeletal muscle toward greater fatty acid oxidation in animal models, which is one reason it drew interest for metabolic disease and exercise research. The exact downstream effects depend on tissue, species, dose, and duration. Human data are sparse, so many proposed benefits remain hypotheses rather than established clinical outcomes.
Laboratory studies have examined GW501516 in cell cultures and rodents for conditions such as dyslipidemia, insulin resistance, and obesity. Some trials in humans were initiated, but development was discontinued after preclinical findings raised concerns about cancer in certain models. Those findings do not prove that the compound causes cancer in people, but they contributed to regulatory caution. Later reviews often describe the evidence as preliminary and insufficient for assessing long-term safety.
== Pathophysiology == Organizing pneumonia is usually preceded by some type of lung injury that causes a localized denudation or disruption in continuity of the epithelial basal laminae of the type 1 alveolar pneumocytes that line the alveoli. This injury to the epithelial basal lamina results in inflammatory cells and plasma proteins leaking into the alveolar space and forming fibrin, resulting in an initial fibroblast driven intra-alveolar fibroproliferation. The fibroblasts differentiate into myofibroblasts and continue to form fibrosis resulting in intra-alveolar fibroinflammatory buds (Masson's Bodies) that are characteristic of organizing pneumonia. These Masson's bodies consist of inflammatory cells contained in an extracellular matrix consisting of type I collagen, fibronectin, procollagen type III, tenascin C and proteoglycans. Angiogenesis , or the formation of blood vessels, occurs in the Masson's bodies and this is driven by vascular endothelial growth factor. Remodeling occurs, resulting in the intra-alveolar fibroinflammatory buds (Masson's Bodies) moving into the interstitial space and forming collagen globules that are then covered by type 1 alveolar epithelial cells with well developed basement membranes. These type 1 alveolar epithelial cells (pneumocytes) then proliferate, restoring the continuity and function of the alveolar unit.
=== Asthenia vs. myasthenia === Asthenia or asthaenia (Greek: ἀσθένεια, literally lack of strength but also disease) is a medical term referring to a condition in which the body lacks or has lost strength either as a whole or in any of its parts. It is a poorly defined condition that can include true or primary muscle weakness or perceived muscle weakness. For perceived muscle weakness, asthenia has been described as the feeling of weak or tired muscles in the absence of muscle weakness, that is the muscle can generate a normal amount of force but it is perceived as requiring more effort. General asthenia occurs in many chronic wasting diseases (such as tuberculosis and cancer), sleep disorders or chronic disorders of the heart, lungs or kidneys, and is probably most marked in diseases of the adrenal gland. Moreover, asthenia can be a symptom of mast cell activation syndrome (MCAS). Asthenia may be limited to certain organs or systems of organs, as in asthenopia, characterized by ready fatiguability. Asthenia is also a side effect of some medications and treatments, such as Ritonavir (a protease inhibitor used in HIV treatment). Differentiating psychogenic (perceived) asthenia and true asthenia from myasthenia is often difficult, and in time apparent psychogenic asthenia accompanying many chronic disorders is seen to progress into a primary weakness. Myasthenia or myasthaenia (my- from Greek: μυο meaning "muscle" + -asthenia [ἀσθένεια] meaning "weakness"), or simply muscle weakness, is a lack of muscle strength.
== Manufacturing == Industrial production of cottage cheese relies on two primary methodologies: the traditional cultured method and the direct acid-set method. The global adoption of these processes varies by region due to local clean-label food regulations, factory scales, and consumer flavour preferences. Both processes begin with pasteurised skimmed milk, concentrated non-fat milk, or reconstituted non-fat dry milk to control baseline protein ratios.
The Cytochrome C assembles an apoptosome which activates the Caspase-9 and initiates an executioner Caspase cascade, effectively breaking down DNA into histones and promoting apoptosis. [6]-Gingerol also inhibits the anti-apoptotic Bcl-2 proteins on the surface of mitochondria, which in turn increases the capabilities for the pro-apoptotic Bcl-2 proteins to initiate cell death. Cancer cells exhibit high amounts of growth hormone activator proteins that are expressed through enzyme-coupled signaling pathways. By halting the phosphorylation of PI-3-Kinase the Akt protein cannot bind with its PH domain, effectively deactivating the downstream signal. Successively keeping Bad proteins bound to anti-apoptotic proteins which keeps them from promoting cell growth, consequently, a double negative cellular signaling pathway to promote apoptosis. Cultured human breast cancer cells were subjected to various concentrations of [6]-gingerol to determine the impacts on live cells. These concentration dependent results concluded that there was no impact at 5 μM but a reduction of 16% occurred at 10 μM. [6]-gingerol targeted three specific proteins in breast cancer cells that promote metastasis and while adhesion remained relatively unchanged, [6]-gingerol inhibited the cancer cells from invading and increasing in size. This study suggests the mechanism by which cancer cell growth was impacted was due to a reduction in specific mRNA that transcribes for extracellular degrading enzymes called matrix metalloproteinases (MMP's).
The FBI quickly identified the hijackers, including leader Atta, when his luggage was discovered at Boston's Logan Airport. Atta had been forced to check two of his three bags due to space limitations on the 19-seat commuter flight he took to Boston. Due to a new policy instituted to prevent flight delays, the luggage failed to make it aboard American Airlines Flight 11 as planned. The luggage contained the hijackers' names, assignments, and al-Qaeda connections. "It had all these Arab-language [sic] papers that amounted to the Rosetta stone of the investigation," said one FBI agent. Within hours of the attacks, the FBI released the names and in many cases the personal details of the suspected pilots and hijackers. Abu Jandal, who served as bin Laden's chief bodyguard for years, confirmed the identity of seven hijackers as al-Qaeda members during interrogations with the FBI on September 17. He had been jailed in a Yemeni prison since 2000. On September 27, photos of all 19 hijackers were released, along with information about possible nationalities and aliases. Fifteen of the men were from Saudi Arabia, two were from the United Arab Emirates, one was from Egypt, and one was from Lebanon.
Sources: en.wikipedia.org
== The leading research groups, producers and applications == One of the leading groups in academy for creating ion-trap MMS is Prof. Graham Cooks with his associate Professor Zheng Ouyang at Purdue University. They have built a series of mini mass spectrometer based on quadrupole ion trap called Mini 10, Mini 11, Mini 12. The group used Mini 10 mass spectrometer weighing 10 kg to analyze proteins, peptides and alkaloids in complex plant materials with electrospray ionization ESI and paperspray ionization. The group used low radio frequency of resonant ion ejection to increase mass range up to 17,000 Da proteins. For interfacing ESI source with MMS, a 10 cm stainless steel capillary was fabricated to transfer the ions directly into the vacuum manifold. The resulting high pressure of 20 mTorr, which is several orders of magnitude higher than that used in lab-scale mass spectrometers is compensated by using the pressure-tolerant rectilinear ion trap. One of the key component of this MMS is the commercial turbo-bump and the MS can be operated at 10−3 torr. To overcome the problem of continuous sample introduction because of the small size of the pump, the group developed a technique called discontinuous atmospheric pressure introduction (DAPI). This technique performs direct chemical analysis without sample pretreatment and enables the coupling of miniature mass spectrometers to atmospheric pressure ionization sources, including ESI, atmospheric pressure chemical ionization (APCI), and various ambient ionization sources.
== Chemical structure == The chemical structure of sodium stibogluconate is somewhat ambiguous, and the structure shown above is idealized. Its solutions may contain multiple antimony compounds, although this heterogeneity may be unimportant. It has been speculated that the active species contains only a single antimony centre.
Suvorexant is approved for the treatment of insomnia by the United States Food and Drug Administration (FDA) at doses of 5 to 20 mg and by the Australian Therapeutic Goods Administration (TGA) and Japanese Pharmaceuticals and Medical Devices Agency (PMDA) at doses of 15 mg (in the elderly) and 20 mg (in younger adults). In the United States, the recommended starting dose is 10 mg and the maximum recommended dose is 20 mg. Higher doses of 30 and 40 mg were also submitted to regulatory agencies for approval but were not authorized due to lack of clearly superior efficacy to doses of 15 to 20 mg and concerns about next-day effects and associated impairment (e.g., driving). In addition to the preceding doses, suvorexant has been assessed at higher doses of up to 100 mg in clinical trials. These higher doses appeared to be more effective at promoting sleep than lower doses but produced greater next-day effects. Lower approved doses of suvorexant in the United States in the range of 5 to 10 mg were not extensively evaluated in clinical trials. The American Academy of Sleep Medicine's 2017 clinical practice guidelines recommend the use of suvorexant in the treatment of sleep-onset and sleep-maintenance insomnia along with various other sleep medications. Orexin receptor antagonists are not used as first-line treatments for insomnia due to their costs and concerns about possible misuse liability. Generic formulations of orexin receptor antagonists including suvorexant are not yet available.
Cellulose is an organic compound with the formula (C6H10O5)n, a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the cell walls of green plants, many forms of algae, the oomycetes, and test of sea squirts. Some species of bacteria secrete it to form biofilms. Cellulose is the most abundant organic polymer on Earth. The cellulose content of cotton fibre is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%. Cellulose is used mainly to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon. Conversion of cellulose from energy crops into biofuels such as cellulosic ethanol is under development as a renewable fuel source. Cellulose for industrial use is mainly obtained from wood pulp and cotton. In addition, cellulose exhibits pronounced susceptibility to direct interactions with certain organic liquids, notably formamide and DMSO, and short-chain amines (methylamine, ethylamine) are among the compounds recognized as highly effective swelling agents. Some animals, particularly ruminants and termites, can digest cellulose with the help of symbiotic micro-organisms that live in their guts, such as Trichonympha. In human nutrition, cellulose is a non-digestible constituent of insoluble dietary fiber, acting as a hydrophilic bulking agent for feces and potentially aiding in defecation.
=== Toxins interacting with proteins === Another non-food protein reaction, urushiol-induced contact dermatitis, originates after contact with poison ivy, eastern poison oak, western poison oak, or poison sumac. Urushiol, which is not itself a protein, acts as a hapten and chemically reacts with, binds to, and changes the shape of integral membrane proteins on exposed skin cells. The immune system does not recognize the affected cells as normal parts of the body, causing a T-cell-mediated immune response. Of these poisonous plants, sumac is the most virulent. The resulting dermatological response to the reaction between urushiol and membrane proteins includes redness, swelling, papules, vesicles, blisters, and streaking. Estimates vary on the fraction of the population that will have an immune system response. Approximately 25% of the population will have a strong allergic response to urushiol. In general, approximately 80–90% of adults will develop a rash if they are exposed to 0.0050 mg (7.7×10−5 gr) of purified urushiol. Some people are so sensitive that a molecular trace on the skin can initiate an allergic reaction.
Sources: en.wikipedia.org
In addition, cysteine, tyrosine, and arginine are considered semiessential amino acids, and taurine a semi-essential aminosulfonic acid in children. Some amino acids are conditionally essential for certain ages or medical conditions. Essential amino acids may also vary from species to species. The metabolic pathways that synthesize these monomers are not fully developed. Amino acids are sometimes added to animal feed because some of the components of these feeds, such as soybeans, have low levels of some of the essential amino acids, especially of lysine, methionine, threonine, and tryptophan. Likewise amino acids are used to chelate metal cations in order to improve the absorption of minerals from feed supplements.
The only stable isotopes of thallium (81Tl) are 203Tl and 205Tl, which make up all natural thallium. The five short-lived isotopes 206Tl through 210Tl also occur in nature, but only as part of the natural decay chains of heavier elements. Synthetic radioisotopes are known from 176Tl to 217Tl; the most stable is 204Tl with a half-life of 3.78 years, followed by 202Tl (half-life 12.31 days) and 201Tl (half-life 3.0421 days). The naturally-occurring radioisotopes live minutes only, with the longest being 207Tl, with a half-life of 4.77 minutes. All isotopes of thallium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed. The isotope 204Tl is made by the neutron activation of stable thallium in a nuclear reactor. while 202Tl can be made in a cyclotron as can 201Tl (see section below). In the fully ionized state, the isotope 205Tl81+ becomes unstable, undergoing bound-state β− decay to 205Pb81+ with a half-life of 291+33−27 days, but 203Tl remains stable. 205Tl is the decay product of bismuth-209, an isotope that was once thought to be stable but is now known to undergo alpha decay with an extremely long half-life of 2.01×1019 y. Thus 205Tl is now placed at the end of the neptunium decay chain.
Performance of manufactured batteries has improved over time. For example, from 1991 to 2005 the energy capacity per price of lithium-ion batteries improved more than ten-fold, from 0.3 W·h per dollar to over 3 W·h per dollar. In the period from 2011 to 2017, progress has averaged 7.5% annually. Overall, between 1991 and 2024, prices for all types of lithium-ion cells (in dollars per kWh) fell approximately 99%. From 1991 to 2018, energy density more than tripled. Efforts to increase energy density contributed significantly to cost reduction. Energy density can also be increased by improvements in the chemistry of the cell, for instance, by full or partial replacement of graphite with silicon. Silicon anodes enhanced with graphene nanotubes to eliminate the premature degradation of silicon allow for record-breaking battery energy density of up to 350 Wh/kg and lowering EV prices to be competitive with ICEs. Differently sized cells of the same format (shape) with the same chemistry may have different energy densities. Jelly roll cells usually have a higher energy density than coin or prismatic cells of the same Ah, because of a tighter/compresses packing of the cell layers. Among cylindrical cells, those with a larger size have a larger energy density, albeit the exact value strongly depends on the thickness of the electrode layers. The disadvantage of large cells is decrease of the heat transfer from the cell to its surroundings.
In the United States domestic market, the chain fell to third place in terms of same-store sales behind Ohio-based Wendy's. The decline was the result of 11 consecutive quarters of same store sales decline. In August 2014, 3G announced that it planned to acquire the Canadian restaurant and coffee shop chain Tim Hortons and merge it with Burger King with backing from Warren Buffett's Berkshire Hathaway. The two chains retained separate operations post-merger, with Burger King remaining in its Miami headquarters. A Tim Hortons representative stated that the proposed merger would allow Tim Hortons to leverage Burger King's resources for international growth. The combined company became the third-largest international chain of fast food restaurants. The deal led to a controversy over the practice of tax inversions, in which a company decreases the amount of taxes it pays by moving its headquarters to a tax haven, a country with lower rates, but maintains the majority of their operations in their previous location. As a high-profile instance of tax inversion, news of the merger was criticized by U.S. politicians, who felt that the move would result in a loss of tax revenue to foreign interests, and could result in further government pressure against inversions. In 2019, Burger King reported that it planned to close up to 250 low-volume locations per year, with closures coming into effect in 2020. In February 2021, Burger King began testing a customer loyalty rewards program called "Royal Perks" in Los Angeles, Miami, New York City, New Jersey, and Long Island, New York.
==== Anti-seizure medication ==== The anti-convulsant medications gabapentin and pregabalin may be used to reduce pain. There is tentative evidence that gabapentin may be of benefit for pain in about 18% of people with fibromyalgia. It is not possible to predict who will benefit, and a short trial may be recommended to test the effectiveness of this type of medication. Approximately 6/10 people who take gabapentin to treat pain related to fibromyalgia experience unpleasant side effects such as dizziness, abnormal walking, or swelling from fluid accumulation. Pregabalin demonstrates a benefit in about 9% of people, it may also enhance sleep quality. Pregabalin reduced time off work by 0.2 days per week. A 2025 review found that, for enhancing sleep quality in FM, pregabalin might be beneficial but had potential risks.
Sources: en.wikipedia.org
No. Cardarine is GW501516, a PPARδ agonist, while SARMs act on androgen receptors. The two classes are often grouped in informal discussions despite different mechanisms.
No. It has no approved medical indication in any country. Regulatory agencies have not cleared it for treatment or prevention of any condition.
Early clinical work stopped after rodent carcinogenicity findings. Those animal results raised concerns about long-term human risk, although direct human evidence is lacking. The human relevance of the tumors remains an open scientific question.
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.