Everything below concerns PPARδ agonist. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-03-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Cardarine is a common name for GW501516, a synthetic compound developed in the 1990s through research collaborations involving GlaxoSmithKline. It belongs to a class of molecules known as peroxisome proliferator-activated receptor delta agonists. Early studies explored its effects on lipid metabolism and energy expenditure in animal models. The compound was never approved as a human medicine, and clinical development was discontinued. In the years since, it has appeared in fitness and bodybuilding communities as a performance-enhancing substance. Regulatory agencies classify it as an unapproved drug.
PPARδ is a nuclear receptor that regulates gene expression related to fatty acid oxidation, glucose homeostasis, and mitochondrial function. GW501516 binds to this receptor with high affinity and activates downstream signaling in skeletal muscle and other tissues. Animal studies reported increased endurance and altered fuel preference, but human data remain limited and inconsistent. The precise relationship between receptor activation and observed physiological changes is still an area of active investigation. Researchers have also examined whether the compound affects inflammation or cell proliferation. No approved therapeutic indication exists for cardarine.
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.
Regulatory treatment of cardarine differs by context and jurisdiction. In competitive sport, the World Anti-Doping Agency lists PPARδ agonists, including GW501516, as prohibited at all times. Outside sport, it lacks approval as a prescription medicine in major drug markets, and products sold for human consumption may be treated as unapproved drugs. Some countries also restrict importation or sale through general consumer protection and medicines laws. These classifications affect availability, testing, and legal risk without establishing therapeutic value.
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.
| Property | Value | Notes |
|---|---|---|
| CAS Registry Number | 317318-70-0 | Unique identifier for the compound. |
| Chemical class | PPARδ agonist | Synthetic ligand for peroxisome proliferator-activated receptor delta. |
| Appearance | White to off-white solid | Typical form of research-grade material. |
| Solubility | Soluble in DMSO and ethanol | Poorly soluble in water. |
| Typical storage | -20°C | Recommended for long-term storage of stock solutions. |
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.
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.
GW501516 acts as a ligand for PPAR delta, a nuclear receptor that regulates transcription of genes involved in fatty acid oxidation and energy use. Activation of this receptor in skeletal muscle shifts metabolism toward fat burning in animal models. The compound does not burn fat directly; it changes gene expression over hours to days. Researchers study it to understand metabolic flexibility and exercise adaptation. Effects observed in rodents are not automatically expected in humans.
Preclinical research reported that GW501516 increased running endurance in mice and improved lipid profiles in some animal species. Early human trials explored effects on high-density lipoprotein cholesterol, triglycerides, and glucose handling, but the program was discontinued. Published human data are sparse and do not establish efficacy for any condition. Studies also examined PPAR delta in cancer biology, with conflicting findings across models. The relationship between receptor activation, tissue context, and disease risk remains an active area of investigation.
Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.
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.
=== Mass spectrometry === MALDI-TOF (Matrix-assisted laser desorption/ionization - time of flight) is a specific type of mass spectrometry that is able to identify microorganisms. A pure culture is isolated and spread directly on a stainless steel or disposable target. The cells are lysed and overlaid with a matrix, which forms protein complexes with the bacterial proteins. The MALDI fires a laser and ionizes the protein complexes, which break off and travel up the vacuum where they are detected based on mass and charge. The resulting protein spectra is compared to a known database of previously catalogued organisms, resulting in rapid diagnosis of microorganisms. Recent studies have suggested that these tests can become specific enough to diagnose down to the sub-species level by observing novel biomarkers. The MALDI-TOF identification method requires pure cultures that are less than 72 hours old. This places the organism in log phase with an abundance of ribosomal proteins, which are the most common proteins detected in the spectra. Identifications with this technology can also be impacted if the culture is exposed to cold temperatures, as this would change the typical protein distribution.
The socialists proposed the full integration of Spain into Europe, but when they took office the negotiations for the accession to the European Economic Community (EEC) were still blocked because of the "pause" in the enlargement imposed by the French president Giscard d'Estaing. However, the triumph in the presidential elections of the socialist François Mitterrand allowed rapid progress in the negotiations and so on June 12, 1985, the EEC accession treaty was signed and on January 1, 1986, Spain joined the EEC together with Portugal.
=== Photodynamic (PDT) mechanism === PDT can induce many cellular pathways, and its main purpose is to induce cell death, either by apoptosis or necrosis. The fundamental process of photodynamic reactions involves three elements: photosensitizers (PS), light of a specific wavelength, and oxygen present in the cell. The interaction of these three components produced a desirable effect inside targeted tissues. Apart from light and oxygen, photosensitizers are compounds designed to absorb light at particular wavelengths during therapy, which enables them to initiate therapeutic processes. Two pathway branches interact and contribute to different ratios during PDT therapy, affecting its efficiency. Both mechanisms have the same first stage. When cells absorb photosensitizers and are exposed to light that aligns with their absorption spectrum, these substances photo-excite from their stable ground state (S°) to an energised excited singlet state (S1). Some energy is emitted as fluorescence, remaining energy directs the photosensitizer molecule into triplet state T1. Type I pathway of photodynamic reaction: T1 state PS can then interact with nearby molecules. Energy transfers between the photosensitizer and other molecules in the form of hydrogen and electrons, resulting in the creation of free radicals and anion radicals. These radicals remain in ground state and react with oxygen, leading to the formation of reactive oxygen species (ROS) and superoxide anion radicals (O2•−), which further react with oxygen to generate ROS.
Sources: en.wikipedia.org
A 1992 World Health Organization report described normal human semen as having a volume of 2 mL or greater, pH of 7.2 to 8.0, sperm concentration of 20×106 spermatozoa/mL or more, sperm count of 40×106 spermatozoa per ejaculate or more, and motility of 50% or more with forward progression (categories a and b) of 25% or more with rapid progression (category a) within 60 minutes of ejaculation. A 2005 review of the literature found that the average reported physical and chemical properties of human semen were as follows:
==== In human fetuses ==== In human embryos and fetuses, ethanol is not metabolized via ADH as ADH enzymes are not yet expressed to any significant quantity in human fetal liver (the induction of ADH only starts after birth, and requires years to reach adult levels). Accordingly, the fetal liver cannot metabolize ethanol or other low molecular weight xenobiotics. In fetuses, ethanol is instead metabolized at much slower rates by different enzymes from the cytochrome P-450 superfamily (CYP), in particular by CYP2E1. The low fetal rate of ethanol clearance is responsible for the important observation that the fetal compartment retains high levels of ethanol long after ethanol has been cleared from the maternal circulation by the adult ADH activity in the maternal liver. CYP2E1 expression and activity have been detected in various human fetal tissues after the onset of organogenesis (ca 50 days of gestation). Exposure to ethanol is known to promote further induction of this enzyme in fetal and adult tissues. CYP2E1 is a major contributor to the so-called Microsomal Ethanol Oxidizing System (MEOS) and its activity in fetal tissues is thought to contribute significantly to the toxicity of maternal ethanol consumption. In presence of ethanol and oxygen, CYP2E1 is known to release superoxide radicals and induce the oxidation of polyunsaturated fatty acids to toxic aldehyde products like 4-hydroxynonenal (HNE). The concentration of alcohol in breast milk produced during lactation is closely correlated to the individual's blood alcohol content.
=== Age-related differences === While the amino acid scores for PDCAAS and DIAAS are based on toddler requirements (1–3 year olds), the essential amino acid requirements differ for adults and infants. The most demanding essential amino acid requirements are for infants; when children become adults, they need lower proportions of essential amino acids. This also means that many of the vegan protein sources that are limited in one or more essential amino acids, are actually less deficient in essential amino acids for adults, perhaps not deficient at all. Old age and pregnancy also change amino acid requirements, because of the necessity of supporting a fetus or slowing the loss of muscle due to age. The essential amino acid requirements for infants are based on the essential amino acid proportions in human breast milk.
Sources: en.wikipedia.org
=== Alzheimer's disease === Considerable interest in IDE has been stimulated due to the discovery that IDE can degrade amyloid beta (Aβ), a peptide implicated in the pathogenesis of Alzheimer's disease. The underlying cause or causes of the disease are unclear, though the primary neuropathology observed is the formation of amyloid plaques and neurofibrillary tangles. One hypothesized mechanism of disease, called the amyloid hypothesis, suggests that the causative agent is the hydrophobic peptide Aβ, which forms quaternary structures that, by an unclear mechanism, cause neuronal death. Aβ is a byproduct generated as the result of proteolytic processing of the amyloid precursor protein (APP) by proteases referred to as the β and γ secretases. The physiological role of this processing is unclear, though it may play a role in nervous system development. Numerous in vitro and in vivo studies have shown correlations between IDE, Aβ degradation, and Alzheimer's disease. Mice engineered to lack both alleles of the IDE gene exhibit a 50% decrease in Aβ degradation, resulting in cerebral accumulation of Aβ. Studies of genetically inherited forms of Alzheimer's show reduction in both IDE expression and catalytic activity among affected individuals. Despite the evident role of IDE in disease, relatively little is known about its physiological functions. These may be diverse, as IDE has been localized to several locations, including the cytosol, peroxisomes, endosomes, proteasome complexes, and the surface of cerebrovascular endothelial cells.
==== Zinc intoxication ==== Zinc intoxication may cause anemia by blocking the absorption of copper from the stomach and duodenum. Zinc also upregulates the expression of chelator metallothionein in enterocytes, which are the majority of cells in the intestinal epithelium. Since copper has a higher affinity for metallothionein than zinc, the copper will remain bound inside the enterocyte, which will be later eliminated through the lumen. This mechanism is exploited therapeutically to achieve negative balance in Wilson's disease, which involves an excess of copper. But in copper-deficient individuals, zinc excess may cause this mechanism to further deplete copper levels.
Additional design elements are common among contemporary In-N-Out locations. Matching In-N-Out's California-inspired palm tree theme, palm trees are sometimes planted to form an "X" in front of the restaurants. This is an allusion to founder Harry Snyder's favorite movie, Stanley Kramer's It's a Mad, Mad, Mad, Mad World, in which the characters look for a hidden treasure and find it under "the big W" made by four palm trees, with the middle two forming an "X".
Sources: en.wikipedia.org
Cardarine is a common name for GW501516, a synthetic PPARδ agonist developed for research. It has not been approved as a medication in any country. It is classified as an unapproved drug and a prohibited substance in sport.
No. Cardarine is not an anabolic steroid; it belongs to a different chemical class that targets PPARδ. Steroids act primarily through androgen receptors, while cardarine acts through a nuclear receptor involved in metabolism.
Some rodent studies reported increased endurance and changes in fat metabolism after cardarine exposure. Long-term studies in animals also raised concerns about cancer in certain tissues. Human trial data are limited, so these findings cannot be directly translated to people.
Anti-doping laboratories typically use LC-MS/MS to detect GW501516 and its metabolites in urine. The method is sensitive and can identify the compound at low concentrations. Detection depends on sample timing, metabolism, and the specific assay.