PPARδ 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 2025-08-12 and is reviewed periodically as new material appears.
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.
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.
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.
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.
| 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 |
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.
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.
Anti-doping laboratories detect GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be used in some programs. Detection depends on factors such as dose, timing, metabolism, and the sensitivity of the assay. Published methods describe limits of detection in the low nanogram per milliliter range for related compounds. Exact detection windows are not fixed for all situations and remain an area of ongoing study.
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.
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.
==== Carbohydrates ==== Mashua is considered a good source of carbohydrates. The carbohydrate content of the dry weight of mashua is between 69.7–79.5%, depending on factors like growing conditions and variety of mashua species. It primarily comprises starch, which manifests in the form of grains. These starch grains comprise 27% amylose and 73% amylopectin, contributing to the overall carbohydrate profile. Approximately 85% of the starch content is readily digestible, while 15% remains indigestible within the gastrointestinal tract.
In most, but not all cases, nuclear-encoded chloroplast proteins are translated with a cleavable transit peptide that's added to the N-terminus of the protein precursor. Sometimes the transit sequence is found on the C-terminus of the protein, or within the functional part of the protein.
=== Hemorrhagic === Hemorrhagic smallpox is a severe form accompanied by extensive bleeding into the skin, mucous membranes, gastrointestinal tract, and viscera. This form develops in approximately 2% of infections and occurs mostly in adults. Pustules do not typically form in hemorrhagic smallpox. Instead, bleeding occurs under the skin, making it look charred and black, hence this form of the disease is also referred to as variola nigra or "black pox". Hemorrhagic smallpox has very rarely been caused by variola minor virus. While bleeding may occur in mild cases and not affect outcomes, hemorrhagic smallpox is typically fatal. Vaccination does not appear to provide any immunity to either form of hemorrhagic smallpox and some cases even occurred among people that were revaccinated shortly before. It has two forms.
=== Hybrids and sub-cultivars === There are a wide variety of breeds for consumer and commercial use of jalapeño plants. The majority fall under one of four categories: F1 hybrids, where the parent plants have been hand-emasculated and cross-bred to produce uniform offspring with hybrid vigor; cultivars which are F-11 or F-12 hybrids or later generations where a stable unique population has been developed; landraces; and F2 hybrids. F1 hybrids produce the highest and most uniform yields but cost 25 times the cost of open-pollinated seed, leading to only 2% of the farmland dedicated to jalapeño cultivation in the United States being planted with F1 hybrids. F2 hybrids often produce similarly to F1 hybrids; however, some F1 hybrids are produced via recessive male sterility to eliminate the need to hand-pollinate, reducing the cost to produce the hybrid, but producing a 25% reduction in yield in the F2 generation. Some notable F1 hybrids are 'Mitla', 'Perfecto', 'Tula', 'Grande' (a hot jalapeño), 'Sayula', 'Senorita', and 'Torreon', most of them being developed and marketed by Petoseed, a brand of Seminis. Cultivars are researched and created to promote desirable traits. Common traits selected for are resistance to viruses and other pepper-related diseases, milder peppers, early ripening, more attractive fruit in terms of size, wall thickness, and corking, and higher yields.
Sources: en.wikipedia.org
Stuart Joseph Patton (November 2, 1920 – October 9, 2017) was an American dairy scientist known for his research in the fields of milk chemistry and the biological processes that regulate milk synthesis in the mammary gland. He was professor of dairy science/food science at Pennsylvania State University from 1949 to 1980 and adjunct professor in the Department of Neurosciences, School of Medicine, University of California, San Diego, and in the School of Family Studies and Consumer Sciences at San Diego State University until his retirement in 2001.
=== Gestational breast hypertrophy === This same effect can also occur at the onset of pregnancy or between the 16th to 20th week of gestation. When the swelling in the connective tissue occurs after birth, it can negatively impact long term milk supply. The swelling increases with each subsequent pregnancy. The extremely rapid growth of the breasts can result in intense heat. The woman's breasts can generate extraordinary discomfort, turning feverish, red, itchy, and even causing the skin to peel. The swelling can suppress the milk supply, pinching off the milk ducts, and leading to mastitis. Gestational gigantomastia is estimated to occur in 1 out of every 28,000 to 100,000 pregnancies. Breast size in women with gestational breast hypertrophy typically reverts to approximately pre-pregnancy size or near it after pregnancy and cessation of breastfeeding. This is not always the case however and in some only partial reduction in breast size may occur, necessitating surgical breast reduction.
Despite the acquisitions by big tobacco companies, some independent e-cigarette companies had more success, most notably Juul Labs, as of 2018. As of 2018, 95% of e-cigarettes were made in China. Despite international growth of e-cigarettes during the 2010s, not all regions around the world have yet embraced it as much. In 2018, Indonesia became only one of the first in Asia or the Global South to recognise e-cigarettes as a genuine alternative to smoking tobacco.
Yu-Shan Lin is a computational chemist. She is a professor and chair of the Department of Chemistry at Tufts University in the United States. Her research lab uses computational chemistry to understand and design biomolecules, with topics focusing on cyclic peptides, protein folding, and collagen.
Robert E Synovec (born 1959) is an American analytical chemist and professor of chemistry at the University of Washington where he specializes in multidimensional separations and chemometrics. Synovec has received several awards for his contributions to analytical chemistry and separation science, including the GC×GC Scientific Achievement Award and the Marcel E Golay Award, which is given for recognition of a lifetime of achievement in capillary chromatography.
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 is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.