PPARδ is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-01-14. Where a claim depends on a specific study, the study is described rather than over-claimed.
Cardarine is a synthetic compound also known as GW501516, GW-501516, and sometimes endurobol. It was developed as a selective agonist of peroxisome proliferator-activated receptor delta, a nuclear receptor involved in fatty acid oxidation and energy metabolism. The compound was studied in preclinical models for metabolic and cardiovascular conditions, but it did not become a marketed human medicine. In regulatory and anti-doping contexts, it is treated as a prohibited substance rather than a licensed medicine.
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.
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.
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 |
|---|---|---|
| Common synonyms | GW501516, GW-501516, GW 501516, endurobol | Names vary in research and anti-doping documents. |
| Chemical class | Synthetic PPARδ agonist | Small-molecule nuclear receptor ligand. |
| CAS Registry Number | 317318-70-0 | Identifier commonly associated with GW501516. |
| Appearance | White to off-white powder | Typical for purified research material. |
| Solubility | Low in water; soluble in DMSO and ethanol | Organic solvents are common for laboratory stock solutions. |
As can be inferred, there is a limited range of molecular weights that can be separated by each column, therefore the size of the pores for the packing should be chosen according to the range of molecular weight of analytes to be separated. For polymer separations the pore sizes should be on the order of the polymers being analyzed. If a sample has a broad molecular weight range it may be necessary to use several GPC columns with varying pores volumes in tandem to resolve the sample fully.
=== Gelator === Gelators serve as stabilizers and thickeners, thickening the gel solution while simultaneously maintaining the gel's flexible nature. When dispersed through the solvent as a colloid, gelators offer a stable internal structure to the gel. Gelators are usually chosen based on their affinity for the solvent and the purpose of the gel. The nature of the gelators used determines the rigidity of the gel. There are many types of gelators, of which carbomers are more frequently used due to their ability to thicken gels across a wide range of pH. Gelators can be classified by polymer types, namely natural, semi-synthetic and synthetic polymers. Natural gelators include tragacanth, gelatin, collagen, and guar gum; semi-synthetic gelators include methylcellulose and other cellulose derivatives; while synthetic gelators include carbomers, polyvinyl alcohol, polyethylene and its copolymers.
The cell membrane, or plasma membrane, is a selectively permeable membrane as an outer boundary of the cell that encloses the cytoplasm. Underlying, and attached to the cell membrane is the cell cortex, the outermost part of the actin cytoskeleton. The membrane serves to separate and protect a cell from its surrounding environment and is made mostly from a lipid bilayer of phospholipids, which are amphiphilic (partly hydrophobic and partly hydrophilic). It has been best described in the fluid mosaic model. Embedded within the cell membrane are secretory macromolecular lipoprotein structures called porosomes; and a number of different channels and pumps involved in actively transporting molecules into and out of the cell. The membrane is semi-permeable, and selectively permeable, in that it can either let a substance (molecule or ion) pass through freely, to a limited extent or not at all. Cell surface receptors in the membrane allow cells to detect external signaling molecules such as hormones.
Sources: en.wikipedia.org
== Further reading == Abbott, Andrew (2001). Chaos of Disciplines. University of Chicago Press. ISBN 978-0-226-00101-2. Oleson, Alexandra; Voss, John (1979). The Organization of knowledge in modern America, 1860–1920. Johns Hopkins University Press. ISBN 0-8018-2108-8. US Department of Education Institute of Education Sciences. Classification of Instructional Programs (CIP). National Center for Education Statistics.
=== Coupling CE with MALDI-MS === Off-line coupling of CE to MALDI, the CE effluent could be sprayed or added drop wise on MALDI target plate then dried and analyzed by MS. For online coupling, a moving target with continuous contact to CE capillary end is required. The moving target takes analytes into MS where it is desorbed and ionized. Musyimi et al. developed a new technique where rotating ball was used to transfer CE to MS. The sample from CE is mixed with matrix coming though another capillary. As the ball rotates the sample is dried before it reaches ionization region. This technique has high sensitivity since no makeup fluid is used.
) is a pharmacokinetic parameter representing the efficiency of drug elimination. This is the rate of elimination of a substance divided by its concentration. The parameter also indicates the theoretical volume of plasma from which a substance would be completely removed per unit time. Usually, clearance is measured in L/h or mL/min. Excretion, on the other hand, is a measurement of the amount of a substance removed from the body per unit time (e.g., mg/min, μg/min, etc.). While clearance and excretion of a substance are related, they are not the same thing. The concept of clearance was described by Thomas Addis, a graduate of the University of Edinburgh Medical School. Substances in the body can be cleared by various organs, including the kidneys, liver, lungs, etc. Thus, total body clearance is equal to the sum clearance of the substance by each organ (e.g., renal clearance + hepatic clearance + pulmonary clearance = total body clearance). For many drugs, however, clearance is solely a function of renal excretion. In these cases, clearance is almost synonymous with renal clearance or renal plasma clearance. Each substance has a specific clearance that depends on how the substance is handled by the nephron. Clearance is a function of 1) glomerular filtration, 2) secretion from the peritubular capillaries to the nephron, and 3) reabsorption from the nephron back to the peritubular capillaries.
Sources: en.wikipedia.org
In 1897, German physicist and chemist Walther Nernst developed the Nernst lamp, a form of incandescent lamp that used a ceramic globar and did not require enclosure in a vacuum or inert gas. Twice as efficient as carbon filament lamps, Nernst lamps were briefly popular until overtaken by lamps using metal filaments.
The material of choice of a given era is often a defining point. Phases such as Stone Age, Bronze Age, Iron Age, and Steel Age are historic, if arbitrary examples. Originally deriving from the manufacture of ceramics and its putative derivative metallurgy, materials science is one of the oldest forms of engineering and applied science. Modern materials science evolved directly from metallurgy, which itself evolved from the use of fire. A major breakthrough in the understanding of materials occurred in the late 19th century, when the American scientist Josiah Willard Gibbs demonstrated that the thermodynamic properties related to atomic structure in various phases are related to the physical properties of a material. Important elements of modern materials science were products of the Space Race; the understanding and engineering of the metallic alloys, and silica and carbon materials, used in building space vehicles enabling the exploration of space. Materials science has driven, and been driven by, the development of revolutionary technologies such as rubbers, plastics, semiconductors, and biomaterials. Before the 1960s (and in some cases decades after), many eventual materials science departments were metallurgy or ceramics engineering departments, reflecting the 19th and early 20th-century emphasis on metals and ceramics.
== History == Originally, the name "Medicare" in the United States referred to a program providing medical care for families of people serving in the military as part of the Dependents' Medical Care Act, which was passed in 1956. President Dwight D. Eisenhower held the first White House Conference on Aging in January 1961, in which creating a health care program for social security beneficiaries was proposed. President Lyndon B. Johnson signed the Social Security Amendments on July 30, 1965, establishing both Medicare and Medicaid. Arthur E. Hess, a deputy commissioner of the Social Security Administration, was named as first director of the Bureau of Health Insurance in 1965, placing him as the first executive in charge of the Medicare program. At the time, the program provided health insurance to 19 million Americans. The Social Security Administration (SSA) became responsible for the administration of Medicare and the Social and Rehabilitation Service (SRS) became responsible for the administration of Medicaid. Both agencies were organized under what was then known as the Department of Health, Education, and Welfare (HEW), in 1965. Since then, HEW, has been reorganized as the Department of Health and Human Services (HHS) in 1980. This consequently brought Medicare and Medicaid under the jurisdiction of the HHS. In March 1977, the Health Care Financing Administration (HCFA) was established under HEW. HCFA became responsible for the coordination of Medicare and Medicaid.
The relatively recent emergence of Salvia divinorum in modern Western culture, in comparison to its long continuing traditions of Indigenous use, contrasts widely differing attitudes on the subject. Opinions range from veneration of the plant as a spiritual sacrament or "a gift from the gods" to a "threat to society," to be banned as quickly as possible in order to "spare countless families the horror of losing a loved one to the relentless tentacles of drug abuse".
Sources: en.wikipedia.org
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.
No. Cardarine is not a steroid hormone; it targets the nuclear receptor PPARδ. Its classification in anti-doping rules differs from anabolic steroids, though it remains prohibited in sport.
Early rodent studies reported tumor formation at multiple sites, which raised safety concerns. Sponsors stopped clinical development, and no approved human product exists.
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.