If you have been reading about regulatory status and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-06-10. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Stability of GW501516 depends on form, temperature, light exposure, and moisture. Solid reference material is typically stored frozen or refrigerated in a desiccator and protected from light. Solutions in organic solvents such as dimethyl sulfoxide are often kept frozen in aliquots to reduce freeze-thaw cycling. Aqueous solubility is low, so aqueous stock solutions can be difficult to prepare without cosolvents. Degradation may appear as changes in chromatographic purity or mass spectral signal. Stability studies are needed to establish shelf life for any specific preparation.
Quality assessment for cardarine samples usually combines identity, purity, and impurity testing. Nuclear magnetic resonance spectroscopy and mass spectrometry can confirm molecular structure, while high-performance liquid chromatography estimates purity. Certificates of analysis from testing laboratories may list these results, but they do not establish safety or legality. In the absence of approved manufacturing, products sold online may contain the wrong compound, variable amounts, or unlisted contaminants. Independent verification is therefore central to analytical work and to interpreting any reported biological activity.
| 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. |
Legal status varies by country. In some places, cardarine is controlled under medicines or psychoactive substances laws; in others, it may be sold with minimal oversight as a research chemical. Customs agencies have intercepted shipments, and several national health agencies have issued warnings about products marketed for bodybuilding or performance enhancement. The lack of a standardized pharmaceutical supply means identity, purity, and contamination levels can differ widely between samples. These factors make cardarine a regulatory and public health concern rather than a conventional prescription drug.
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.
Literature on cardarine often separates receptor pharmacology from toxicology. Mechanistic papers describe PPARδ activation and gene expression changes, while safety assessments focus on carcinogenicity and species differences. Questions remain about whether rodent tumors arise through PPARδ-dependent or off-target mechanisms. Another open area is how human metabolism and exposure compare with those in animal studies. Analytical methods such as liquid chromatography–mass spectrometry are used to confirm identity in biological and product samples.
GW501516 acts as an agonist at the peroxisome proliferator-activated receptor delta, a nuclear receptor that regulates gene expression. Activation shifts transcription toward genes involved in fatty acid uptake, oxidation, and energy expenditure. The compound does not bind the androgen receptor and therefore differs from anabolic steroids and SARMs. In rodent models, this metabolic shift has been linked to increased running endurance and reduced fat accumulation. The exact downstream pathways in humans remain incompletely characterized.
=== Kidney involvement === Renal involvement is a key complication of MCTD. Some studies show that it affects around 25% of people and is generally asymptomatic. The most prevalent finding is membranous nephropathy; however, nephrotic range proteinuria may also occur. Tubulointerstitial nephritis, mesangioproliferative glomerulonephritis, and hypertensive episodes resembling scleroderma renal crisis have also been observed.
== Organisms and discovery == Creatinase was first identified by Roche, Lacombe, & Girard in 1950 in Pseudomonas eisenbergii and P. ovalis. It is produced by other bacterial genera including Bacillus, Flavobacterium, Micrococcus, Alcaligenes, Clostridium, Arthrobacter, and Paracoccus, and is produced by other species of Pseudomonas as well. In P. putida, creatinase is coded for by the creA gene and enables growth on creatine as the sole nitrogen source. Expression of creA is regulated by CahR, an AraC/GAT-R regulator that activates gene expression in the presence of creatine. This gene has also been cloned into Escherichia coli.
The conclusion of the report, which was not published, mentioned the Balfour Declaration three times, stating that "the causes of the alienation and exasperation of the feelings of the population of Palestine" included:
=== αvβ6-integrin target === The abundance of αvβ6-integrin on most adult human cell types and respective tissues is low. It is however overexpressed in the context of several medical conditions, such as cancer or fibrosis, particularly idiopathic pulmonary fibrosis. In line with the finding that αvβ6-integrin is expressed by epithelial cells, an elevated density of the protein is observed on the cell surfaces of many carcinomas (synonymous to cancers of epithelial origin). Hence, 68Ga-Trivehexin can be used for PET imaging of αvβ6-integrin positive cancers (i.e., those whose cells possess a sufficiently high density of αvβ6 on their surface), including but not limited to pancreatic ductal adenocarcinoma, non-small cell lung cancer, squamous cell carcinomas (SCC) of different origin (most notably, oral and esophageal SCC), as well as breast, ovarian, and bladder cancer. In colorectal cancer, expression of αvβ6-integrin is higher in the more aggressive forms and correlated with reduced overall survival. 68Ga-Trivehexin has a high binding affinity to αvβ6-integrin (IC50 = 0.047 nM). Its affinity to other RGD-binding integrins is much lower (IC50 for αvβ3, αvβ8, and α5β1 are 2.7, 6.2, and 22 nM, respectively; note that for IC50, higher values mean lower affinity), resulting in a high selectivity for αvβ6-integrin.
Sources: en.wikipedia.org
The lungs have a dual blood supply provided by a bronchial and a pulmonary circulation. The bronchial circulation supplies oxygenated blood to the airways of the lungs, through the bronchial arteries that leave the aorta. There are usually three arteries, two to the left lung and one to the right, and they branch alongside the bronchi and bronchioles. The pulmonary circulation carries deoxygenated blood from the heart to the lungs and returns the oxygenated blood to the heart to supply the rest of the body. The blood volume of the lungs is about 450 millilitres on average, about 9% of the total blood volume of the entire circulatory system. This quantity can easily fluctuate from between one-half and twice the normal volume. Also, in the event of blood loss through hemorrhage, blood from the lungs can partially compensate by automatically transferring to the systemic circulation.
== Multicellularity == Very few multicellular life forms are anaerobic, since only aerobic respiration can provide enough energy for a complex metabolism. Exceptions include three species of Loricifera (< 1 mm in size) and the 10-cell Henneguya zschokkei. In 2010, three species of anaerobic Loricifera were discovered in the hypersaline anoxic L'Atalante basin at the bottom of the Mediterranean Sea. They lack mitochondria, which contain the oxidative phosphorylation pathway, which in all other animals combines oxygen with glucose to produce metabolic energy; thus, they consume no oxygen. Instead, these loricifera derive their energy from hydrogen, using hydrogenosomes. Henneguya zschokkei also lack mitochondria, mitochondrial DNA, and oxidative pathways. The microscopic, parasitic cnidarian is observed to contain mitochondria-related organelles. These organelles harbour genes encoding metabolic functions, such as those involved in the amino acid metabolism. However, these specialized organelles lack the key features of typical mitochondria found in the closely related aerobic Myxobolus squamalus. Due to the difficulty of culturing H. zschokkei, there is little understanding of its anaerobic pathway.
==== Martyrs ==== The decision as to whether martyrs had died for their faith in Christ and the consequent permission of veneration lay originally with the bishop of the place in which they had borne their testimony. The bishop inquired into the motive of the person's death and, on finding they had died a martyr, sent their name with an account of their martyrdom to other churches, especially neighboring ones, so that, in the event of approval by their respective bishops, the cultus of the martyr might extend to their churches also and that the faithful, as is said of Ignatius of Antioch in the "Acts" of his martyrdom "might hold communion with the generous martyr of Christ" (generoso Christi martyri communicarent). Martyrs whose cause, so to speak, had been discussed, and the fame of whose martyrdom had been confirmed, were known as proved (vindicati) martyrs. That word probably did not antedate the fourth century, when it was introduced into the Church at Carthage; but the fact is certainly older. In the earlier ages, therefore, this veneration was entirely local and passed from one church to another with the permission of their bishops. This is clear from the fact that in ancient Christian cemeteries there are found paintings of only those martyrs who had suffered in that neighborhood. It explains, also, the almost universal veneration very quickly paid to, e.g., Lawrence, Cyprian, and Sixtus II, who were killed by the Roman Emperor Valerian.
== Geochronological dating == Common methods to find out the ages of hydrothermal vents are to date the sulfide (e.g., pyrite) and sulphate minerals (e.g., baryte). Common dating methods include radiometric dating and electron spin resonance dating. Different dating methods have their own limitations, assumptions and challenges. General challenges include the high purity of extracted minerals required for dating, the age range of each dating method, heating above closure temperatures erasing ages of older minerals, and multiple episodes of mineral formation resulting in a mixture of ages. In environments with multiple phases of mineral formation, generally, electron spin resonance dating gives the average age of the bulk mineral while radiometric dates are biased to the ages of younger phases because of the decay of parent nuclei. These explain why different methods can give different ages to the same sample and why the same hydrothermal chimney can have samples with different ages.
== Construction methodology == The Russell indexes are objectively constructed based on transparent rules. The broadest U.S. Russell Index is the Russell 3000E Index which contains the 4,000 largest (by market capitalization) companies incorporated in the U.S., plus (beginning with the 2007 reconstitution) companies incorporated in an offshore financial center that have their headquarters in the U.S.; a so-called "benefits-driven incorporation". If 4,000 eligible securities do not exist in the U.S. market, the entire eligible set is included. Each Russell Index is a subset of the Russell 3000E Index and broken down by market capitalization and style. The members of the Russell 3000E Index and its subsets are determined each year during annual reconstitution and enhanced quarterly with the addition of initial public offerings (IPOs). The Russell 3000E Index represents approximately 99 percent of the U.S. equity market. Russell excludes stocks trading below $1, stocks that trade on the pink sheets and OTC Bulletin Board, closed-end mutual funds, limited partnerships, royalty trusts, non-U.S. incorporated stocks (other than the benefits driven incorporations described above), foreign stocks, and American Depositary Receipts (ADRs).
Sources: en.wikipedia.org
==== MeSH D06.472.334 – gonadal hormones ==== MeSH D06.472.334.500 – activins MeSH D06.472.334.500.500 – inhibin-beta subunits MeSH D06.472.334.734 – corpus luteum hormones MeSH D06.472.334.734.623 – progesterone MeSH D06.472.334.734.769 – relaxin MeSH D06.472.334.851 – gonadal steroid hormones MeSH D06.472.334.851.437 – estradiol congeners MeSH D06.472.334.851.437.249 – equilenin MeSH D06.472.334.851.437.374 – equilin MeSH D06.472.334.851.437.500 – estradiol MeSH D06.472.334.851.437.750 – estriol MeSH D06.472.334.851.437.750.320 – estetrol MeSH D06.472.334.851.437.968 – estrogenic steroids, alkylated MeSH D06.472.334.851.437.968.500 – ethinyl estradiol MeSH D06.472.334.851.437.968.500.250 – ethinyl estradiol-norgestrel combination MeSH D06.472.334.851.437.968.500.500 – mestranol MeSH D06.472.334.851.437.968.500.750 – quinestrol MeSH D06.472.334.851.437.984 – estrogens, catechol MeSH D06.472.334.851.437.984.350 – hydroxyestrones MeSH D06.472.334.851.437.988 – estrogens, conjugated (usp) MeSH D06.472.334.851.437.994 – estrogens, esterified (usp) MeSH D06.472.334.851.437.996 – estrone MeSH D06.472.334.851.687 – progesterone congeners MeSH D06.472.334.851.687.500 – pregnenolone MeSH D06.472.334.851.687.500.500 – 17-alpha-hydroxypregnenolone MeSH D06.472.334.851.687.750 – progesterone MeSH D06.472.334.851.687.750.074 – 20-alpha-dihydroprogesterone MeSH D06.472.334.851.687.750.099 – 5-alpha-dihydroprogesterone MeSH D06.472.334.851.687.750.478 – hydroxyprogesterones MeSH D06.472.334.851.687.750.478.400 – 17-alpha-hydroxyprogesterone MeSH D06.472.334.851.687.750.478.400.500 – pregnanetriol MeSH D06.472.334.851.687.750.739 – pregnanediol MeSH D06.472.334.851.968 – testosterone congeners MeSH D06.472.334.851.968.500 – androstane-3,17-diol MeSH D06.472.334.851.968.750 – androstenediol MeSH D06.472.334.851.968.875 – androstenedione MeSH D06.472.334.851.968.937 – androsterone MeSH D06.472.334.851.968.952 – dehydroepiandrosterone MeSH D06.472.334.851.968.952.300 – dehydroepiandrosterone sulfate MeSH D06.472.334.851.968.964 – dihydrotestosterone MeSH D06.472.334.851.968.968 – etiocholanolone MeSH D06.472.334.851.968.976 – nandrolone MeSH D06.472.334.851.968.984 – testosterone MeSH D06.472.334.851.968.984.500 – epitestosterone MeSH D06.472.334.851.968.984.750 – testosterone propionate MeSH D06.472.334.968 – inhibins MeSH D06.472.334.968.500 – inhibin-beta subunits MeSH D06.472.334.984 – testicular hormones
== Activism, research centers == The Center for Orphan Drug Research at the University of Minnesota College of Pharmacy helps small companies with insufficient in-house expertise and resources in drug synthesis, formulation, pharmacometrics, and bio-analysis. The Keck Graduate Institute Center for Rare Disease Therapies (CRDT) in Claremont, California, supports projects to revive potential orphan drugs whose development has stalled by identifying barriers to commercialization, such as problems with formulation and bio-processing. Numerous advocacy groups such as the National Organization for Rare Disorders, Global Genes Project, Children's Rare Disease Network, Abetalipoproteinemia Collaboration Foundation, Zellweger Baby Support Network, and the Friedreich's Ataxia Research Alliance have been founded in order to advocate on behalf of patients with rare diseases with a particular emphasis on diseases that affect children.
Vancomycin biosynthesis occurs primarily via three nonribosomal protein syntheses (NRPSs) VpsA, VpsB, and VpsC. The enzymes determine the amino acid sequence during its assembly through its 7 modules. Before vancomycin is assembled through NRPS, the non-proteinogenic amino acids are first synthesized. L-tyrosine is modified to become the β-hydroxytyrosine (β-HT) and 4-hydroxyphenylglycine (4-Hpg) residues. 3,5-dihydroxyphenylglycine ring (3,5-DPG) is derived from acetate.
=== Congestive heart failure === Although beta blockers were once contraindicated in congestive heart failure, as they have the potential to worsen the condition due to their effect of decreasing cardiac contractility, studies in the late 1990s showed their efficacy at reducing morbidity and mortality. Bisoprolol, carvedilol, and sustained-release metoprolol are specifically indicated as adjuncts to standard ACE inhibitor and diuretic therapy in congestive heart failure, although at doses typically much lower than those indicated for other conditions. Beta blockers are only indicated in cases of compensated, stable congestive heart failure; in cases of acute decompensated heart failure, beta blockers will cause a further decrease in ejection fraction, worsening the patient's current symptoms. Beta blockers are known primarily for their reductive effect on heart rate, although this is not the only mechanism of action of importance in congestive heart failure. Beta blockers, in addition to their sympatholytic β1 activity in the heart, influence the renin–angiotensin system at the kidneys. Beta blockers cause a decrease in renin secretion, which in turn reduces the heart oxygen demand by lowering the extracellular volume and increasing the oxygen-carrying capacity of the blood.
=== Lung toxicity === Pulmonary toxicity, or toxicity to lungs, is a serious complication associated with sirolimus therapy, especially in the case of lung transplants. The mechanism of the interstitial pneumonitis caused by sirolimus and other macrolide mTOR inhibitors is unclear, and may have nothing to do with the mTOR pathway. The interstitial pneumonitis is not dose-dependent, but is more common in patients with underlying lung disease.
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.
LC-MS/MS is common, often after sample cleanup. The assay targets GW501516 or its metabolites.