GW501516 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 2025-10-02 and is reviewed periodically as new material appears.
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.
PPARδ is a nuclear receptor that influences transcription of genes involved in fatty acid oxidation, lipid transport, and energy homeostasis. GW501516 binds and activates this receptor with high selectivity relative to PPARα and PPARγ in laboratory assays. Activation alters expression of target genes in skeletal muscle, liver, and adipose tissue in animal models. The exact clinical consequences of these changes in humans remain incompletely characterized, and observed effects in animals do not establish therapeutic benefit or safety.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | PPARδ agonist | Not an anabolic steroid. |
| Common synonyms | GW501516, GW-1516 | Cardarine is an informal name. |
| Appearance | White to off-white powder | Typical for research-grade solid. |
| Solubility class | Poorly soluble in water; soluble in some organic solvents | Such as DMSO or ethanol in laboratory settings. |
| Typical storage temperature | Cool, dry, protected from light | Specific conditions vary by supplier and form. |
Products sold as cardarine have been found to contain incorrect compounds, variable amounts, or no active ingredient at all. Independent testing is required to verify identity and purity. Common analytical approaches include high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance for structural confirmation. These methods can distinguish GW501516 from related PPAR agonists and from unrelated steroids. For regulators and researchers, such verification is central to interpreting both biological results and adverse event reports.
Cardarine is prohibited in competitive sport under the World Anti-Doping Agency code, where it is classified as a metabolic modulator. It is not approved as a prescription medicine in the United States, European Union, or other major markets. Regulatory action has focused on its presence in sports and in products marketed as research chemicals. Because it has no accepted medical indication, supply is often unregulated. This status creates legal and safety uncertainties for anyone who encounters the substance.
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.
== Early life == Shaffer was born on June 19, 1998, in Santa Clarita, California to Ron and Debbie (née Solgot) Shaffer and was named after the fictional character Atticus Finch from the book To Kill a Mockingbird.
However, there is no real demand in chemistry, physics, or engineering for isolating 234U, and the small amounts that may be wanted for research can be separated chemically from plutonium-238 that have been aged enough to accumulate its alpha decay product, which is 234U. Enriched uranium contains more 234U than natural uranium as a byproduct of the uranium enrichment process aimed at obtaining uranium-235, which concentrates lighter isotopes even more strongly than it does 235U. IAEA research paper TECDOC-1529 concludes the 234U content of enriched fuel is directly proportional to the degree of 235U—enrichment with 2% 235U resulting in 150 g 234U/ton HM (heavy metals, special meaning, relating to nuclear fuels), and the most common 4.5% 235U enrichment resulting in 400 g 234U/ton HM. The increased percentage of 234U in enriched natural uranium is not harmful to the operation of current nuclear reactors. Uranium-234 has a neutron-capture cross section of about 100 barns for thermal neutrons, and about 700 barns for its resonance integral—the average of neutrons having a range of intermediate energies. In a nuclear reactor non-fissile isotopes 234U and 238U both capture a neutron, thereby breeding fissile isotopes 235U and 239Pu, respectively. 234U is converted to 235U more easily and therefore at a greater rate than 238U is to 239Pu (via neptunium-239) because 238U has a much smaller neutron-capture cross section of just 2.7 barns.
== Drug interaction == Pioglitazone/metformin may interact with furosemide, nifedipine, cationic drugs (e.g., amiloride, digoxin, morphine, procainamide, quinidine, quinine, ranitidine, triamterene, trimethoprim, and vancomycin) and certain drugs tend to produce hyperglycemia and may lead to loss of glycemic control (e.g., thiazides and other diuretics, corticosteroids, phenothiazines, thyroid products, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, calcium channel blocking drugs, and isoniazid).
== Natural occurrence == Phenethylamine is produced by a wide range of species throughout the plant and animal kingdoms, including humans; it is also produced by certain fungi and bacteria (genera: Lactobacillus, Clostridium, Pseudomonas and the family Enterobacteriaceae) and acts as a potent antimicrobial against certain pathogenic strains of Escherichia coli (e.g., the O157:H7 strain) at sufficient concentrations.
Sources: en.wikipedia.org
Peptide hormones GHRH (somatocrinin) through binding to the growth hormone-releasing hormone receptor (GHRHR) Ghrelin through binding to growth hormone secretagogue receptors (GHSR) Sex hormones Increased androgen secretion during puberty (in males from testes and in females from adrenal cortex) Testosterone and DHEA Estrogen Clonidine, moxonidine and L-DOPA by stimulating GHRH release α4β2 nicotinic agonists, including nicotine, which also act synergistically with clonidine or moxonidine. Hypoglycemia, arginine, pramipexole, lysine, tryptophan, γ-Aminobutyric acid and propranolol by inhibiting somatostatin release Deep sleep Glucagon Sodium oxybate or γ-Hydroxybutyric acid Niacin as nicotinic acid (vitamin B3) Fasting Insulin Vigorous exercise Inhibitors of GH secretion include:
In 2018, the US Special Inspector General for Afghanistan Reconstruction called the counternarcotics operation to date "a total failure". As the US military presence neared an end in 2020, Afghanistan was producing an estimated 85% of the world's opium. Having spent some $9 billion in the 20-year anti-drug campaign, US forces left Afghanistan in 2021, and the Taliban returned to power.
=== Patents and regulatory exclusions === GLP-1 drugs are protected by patents and regulatory exclusivities, which delay generic competitors and keep prices high. The drugs have a median of 20 patents. These patents have protection periods averaging 18 years. The patents apply not only to the drugs but also to injection devices, delivery systems, and other components. Overlapping patents make it hard for generic manufacturers to enter the market. This creates a tradeoff between short-term affordability and long-term pharmaceutical innovation. Semaglutide's main patent expired in 2026 in several countries, but lasts until the early 2030s in many others.
==== Hydrophobic ==== Nonpolar amino acid interactions are the primary driving force behind the processes that fold proteins into their functional three dimensional structures. None of these amino acids' side chains ionize easily, and therefore do not have pKas.
Vortioxetine is well-absorbed when taken orally and has an oral bioavailability of 75%. It is systemically detectable after a single oral dose by 0.781 hours. Peak levels of vortioxetine are reached within 7 to 11 hours post-dose with single or multiple doses. Steady-state levels of vortioxetine are generally reached within 2 weeks of administration, with 90% of individuals reaching 90% of steady state after 12 days of administration. Steady-state peak levels of vortioxetine with doses of 5, 10, and 20 mg/day were 9, 18, and 33 ng/mL, respectively. The accumulation index of vortioxetine (area-under-the-curve levels after a single dose versus at steady state) is 5 to 6. A loading dose given intravenously has been found to achieve steady-state levels more rapidly with oral vortioxetine therapy. The pharmacokinetics of vortioxetine are known to be linear and dose proportional over a range of 2.5 to 75 mg for single doses and 2.5 to 60 mg for multiple doses. Food has no influence on the pharmacokinetics of vortioxetine. The apparent volume of distribution of vortioxetine is large and ranges from 2,500 to 3,400 L after single or multiple doses of 5 to 20 mg vortioxetine, with extensive extravascular distribution. The plasma protein binding of vortioxetine is approximately 98 or 99%, with about 1.25 ± 0.48% free or unbound. Vortioxetine is extensively metabolized by oxidation via cytochrome P450 enzymes and subsequent glucuronidation via UDP-glucuronosyltransferase.
Sources: en.wikipedia.org
== Medical uses == Up to a certain point, the gut can adapt to partial resections that result in short bowel syndrome. Still, parenteral substitution of water, minerals and vitamins (depending on which part of the gut has been removed) is often necessary. Teduglutide may reduce or shorten the necessity of such infusions by improving the intestinal mucosa and possibly by other mechanisms.
During the War of the Triple Alliance, Peru was a country that protested against the alleged attempts to conquer Paraguay by the member countries of the Triple Alliance (of which Argentina was a part together with Uruguay and Brazil). For the rest of the continent, this war was perceived as an attempt to conquer and divide Paraguay among the allies. The attempt against the independence of one of the countries of the continent was feared as a terrible precedent for potential geopolitical disorders and possible expansionist projects in the governments of the area, Argentina being very frowned upon in the eyes of Peru. The controversial Secret Treaty of the Triple Alliance was seen in Peruvian diplomacy as a violation of Paraguay's sovereignty and integrity as a country. Thus, the perception of that war was understood, in the public eye, as the arrogance of 3 allied countries that wanted to seize Paraguay's territory and even destroy its sovereignty, generating analogies with the Second French intervention in Mexico or the Spanish-South American War, that happened simultaneously during the 1860s, comparing them as a form of imperialism not different from that of the Europeans. Seen in this way, no distinction was made regarding a conquest, especially of a Latin American country, by an American government or a European government, in the eyes of society, both acts were reprehensible.
== Pathophysiology == The exact cause of venous ulcers is not certain. A common denominator is generally venous stasis, which may be caused by chronic venous insufficiency, and/or congestive heart failure. Venous stasis causes the pressure in veins to increase. The body needs the pressure gradient between arteries and veins for the heart to pump blood forward through arteries and into veins. When venous hypertension exists, arteries no longer have significantly higher pressure than veins, and blood is not pumped as effectively into or out of the area. Venous hypertension may also stretch veins and allow blood proteins to leak into the extravascular space, isolating extracellular matrix (ECM) molecules and growth factors, preventing them from helping to heal the wound. Leakage of fibrinogen from veins as well as deficiencies in fibrinolysis may also cause fibrin to build up around the vessels, preventing oxygen and nutrients from reaching cells. Venous insufficiency may also cause white blood cells (leukocytes) to accumulate in small blood vessels, releasing inflammatory factors and reactive oxygen species (ROS, free radicals) and further contributing to chronic wound formation. Buildup of white blood cells in small blood vessels may also plug the vessels, further contributing to ischemia. This blockage of blood vessels by leukocytes may be responsible for the "no reflow phenomenon", in which ischemic tissue is never fully reperfused. Allowing blood to flow back into the limb, for example by elevating it, is necessary but also contributes to reperfusion injury.
==== Extrusion-based printing ingredients ==== Common ingredients used in extrusion-based printing are inherently soft enough to extrude from a syringe/printhead and possess a high enough viscosity to retain a shape. In certain cases, powdered ingredients (protein, sugar, etc.) are added to increase viscosity, e.g. adding flour to water creates a paste that can be printed. Inherently soft materials include:
=== Life cycle === Female Osedax worms have been observed spawning both in the wild and in laboratory aquaria. Osedax rubiplumus can spawn hundreds of oocytes at a time. They are already fertilized when they are released from the female worm. The worms' endosymbionts, species of bacteria in the order Oceanospirillales, were not observed in the spawned oocytes, which suggests that they are acquired after the worms settle on the bones. Osedax appears to be highly fecund and reproduces continuously.
Sources: en.wikipedia.org
Cardarine is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.
No, cardarine is not a steroid. It is classified as a PPARδ agonist. Its structure and receptor target differ from anabolic steroids.
No regulatory agency has approved cardarine as a medicine. It was investigated in early research but development was discontinued. It is not available as a prescription drug.
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.