nuclear receptor comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-04-04. Where a claim depends on a specific study, the study is described rather than over-claimed.
Cardarine is the common name for GW501516, a synthetic compound studied as a peroxisome proliferator-activated receptor delta agonist. Researchers developed it to explore treatments for lipid disorders and metabolic conditions. It is not an approved medicine in any country. Early clinical work examined changes in HDL cholesterol and triglycerides, but development was discontinued after animal studies raised concerns about cancer. The compound remains available as a research chemical and appears in discussions of performance enhancement.
At the molecular level, GW501516 binds and activates PPARδ, a nuclear receptor that regulates transcription. Activation shifts expression of genes involved in fatty acid oxidation, energy expenditure, and lipid transport in skeletal muscle and liver. Animal studies report increased endurance and altered lipid profiles after exposure. Human data are limited to small trials and do not establish long-term safety or efficacy. PPARδ also has roles in cell proliferation, so the relationship between activation and cancer risk remains an open question.
Published literature on cardarine includes in vitro assays, rodent experiments, and a small number of human studies. Reports describe effects on exercise capacity and lipid metabolism in animals, while human evidence is sparse. Many online descriptions present the compound as a proven endurance aid, a claim not supported by regulatory approval or large clinical trials. Analytical studies focus on identifying the parent compound and its metabolites in biological samples. Important uncertainties include species differences, dose-response relationships, and the relevance of rodent tumor findings to humans.
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.
The compound is typically described as a laboratory compound rather than a therapeutic product. Published reports have explored its role in lipid disorders, insulin sensitivity, and exercise metabolism, yet no major drug regulator has approved it for medical use. Commercial samples sold under the cardarine name may vary in purity and identity. Analytical confirmation is therefore necessary when the material is discussed in scientific or regulatory contexts. Its classification as a prohibited substance in sport further shapes how it is studied and reported.
| Property | Value | Notes |
|---|---|---|
| Common name | Cardarine | Also called GW501516 and endurobol. |
| Chemical formula | C21H18F3NO3S2 | Molecular weight about 453.5 g/mol. |
| Appearance | White to off-white solid | Form depends on synthesis and purity. |
| Solubility | Soluble in DMSO and ethanol | Low solubility in water. |
| Typical storage | -20 °C, desiccated, protected from light | Common for research chemicals. |
Laboratory detection of cardarine typically involves sample preparation followed by chromatographic separation and mass spectrometric identification. Urine is the most common matrix for anti-doping tests, though blood and hair have also been explored. Methods can target the parent compound or its metabolites, depending on the expected window of detection. Reference standards are required for accurate quantification. Matrix effects and dilution can influence results, so laboratories use internal standards and validation protocols. The exact detection window varies with dose, route, and individual metabolism.
A common misconception is that cardarine has been proven safe for human use. In reality, human clinical data are limited, and long-term animal studies have raised concerns about cancer. Another misconception is that it is a supplement or vitamin-like compound. It is a synthetic research chemical with no approved medical indication. Scientific discussion often focuses on its mechanism and detection rather than therapeutic use. Regulatory and anti-doping literature treats it primarily as a prohibited substance.
In the fitness and bodybuilding literature, cardarine is frequently discussed as an endurance agent or fat-loss compound, although such claims are not supported by robust clinical evidence. Online descriptions often mix animal data, user anecdotes, and marketing language. Researchers who study PPARδ agonists distinguish between receptor activation in controlled experiments and unsupervised use of unverified products. The latter introduces unknown purity, dose, and interactions, making reported experiences difficult to interpret scientifically.
GW501516 acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in transcription of genes related to lipid handling and energy use. Activation of PPARδ can shift skeletal muscle toward greater fatty acid oxidation in animal models, which is one reason it drew interest for metabolic disease and exercise research. The exact downstream effects depend on tissue, species, dose, and duration. Human data are sparse, so many proposed benefits remain hypotheses rather than established clinical outcomes.
Laboratory studies have examined GW501516 in cell cultures and rodents for conditions such as dyslipidemia, insulin resistance, and obesity. Some trials in humans were initiated, but development was discontinued after preclinical findings raised concerns about cancer in certain models. Those findings do not prove that the compound causes cancer in people, but they contributed to regulatory caution. Later reviews often describe the evidence as preliminary and insufficient for assessing long-term safety.
== Education == Suga graduated from Okayama University (BSc, MSc) in engineering, and studied at University of Lausanne, where he worked with Manfred Schlosser. Suga completed his Ph.D. in chemistry at Massachusetts Institute of Technology in 1994 with Satoru Masamune, working on catalytic antibodies
hydrophobic Sometimes used interchangeably with lipophilic. Having a low solubility in or affinity for water or other polar solvents; describing a non-polar molecule, or a moiety or functional group within a molecule, which cannot form energetically favorable interactions with polar compounds and which therefore tends to "avoid" or be repulsed by such compounds, instead clustering together with other hydrophobic molecules or arranging itself in a way that minimizes its exposure to its polar surroundings. This phenomenon is not so much due to the affinity of the hydrophobic molecules for each other as it is a consequence of the strong intermolecular forces that allow polar compounds such as water molecules to bond with each other; hydrophobic species are unable to form alternative bonds of equivalent strength with the polar compounds, hence they tend to be excluded from aqueous solutions by the tendency of the polar solvent to maximize interactions with itself. Hydrophobicity is a major determinant of countless chemical interactions in biological systems, including the spatial conformations assumed by macromolecules such as proteins and lipids, the binding of ligands and substrates to proteins, and the structure and properties of lipid membranes. Contrast hydrophilic.
== Academic amateur diplomat == As an instructor at Harvard, Kissinger published his 1957 book Nuclear Weapons and Foreign Policy, whose popularity established his reputation as one of America's leading thinkers on foreign policy. Kissinger's involvement in Indochina started prior to his appointment as National Security Advisor to Nixon. While still at Harvard, he had worked as a consultant on foreign policy to both the White House and State Department. Kissinger says that "In August 1965 ... [Henry Cabot Lodge Jr.], an old friend serving as Ambassador to Saigon, had asked me to visit Vietnam as his consultant. I toured Vietnam first for two weeks in October and November 1965, again for about ten days in July 1966, and a third time for a few days in October 1966 ... Lodge gave me a free hand to look into any subject of my choice". He became convinced of the meaninglessness of military victories in Vietnam, "... unless they brought about a political reality that could survive our ultimate withdrawal". Lodge allowed Kissinger to go anywhere he wanted, and to meet the ruling duumvirate of Air Marshal Nguyễn Cao Kỳ and General Nguyễn Văn Thiệu. In a gaffe, Kissinger spoke frankly to an American reporter, Jack Foisie, who had arrived late to the press conference and was not aware that the press conference was "off-the-record". Kissinger called both Air Marshal Kỳ and General Thiệu immature men of low intelligence, remarks that Foise published and which drew the ire of President Lyndon B. Johnson.
Sources: en.wikipedia.org
=== Electrical and optical properties === Because honey contains electrolytes, in the form of acids and minerals, it exhibits varying degrees of electrical conductivity. Measurements of the electrical conductivity are used to determine the quality of honey in terms of ash content. The effect honey has on light is useful for determining the type and quality. Variations in its water content alter its refractive index. Water content can easily be measured with a refractometer. Typically, the refractive index for honey ranges from 1.504 at 13% water content to 1.474 at 25%. Honey also has an effect on polarized light, in that it rotates the polarization plane. The fructose gives a negative rotation, while the glucose gives a positive one. The overall rotation can be used to measure the ratio of the mixture. Honey is generally pale yellow and dark brown in color, but other colors can occur, depending on the sugar source. Bee colonies that forage on Kudzu (Pueraria montana var. lobata) flowers, for example, produce honey that varies in color from red to purple.
== Diet == The house cricket is an omnivore that eats a range of plant and animal matter. Crickets in the wild consume flowers, leaves, fruits, grasses and other insects (including dead members of their own species). Crickets in captivity will accept fruits (e.g. apples, oranges, bananas), vegetables (e.g. potatoes, carrots, squash, leafy vegetables), grains (e.g. oatmeal, cornmeal, cooked corncobs, alfalfa, wheat germ, rice cereal), various pet foods and commercial cricket food.
=== Elimination === Alcohol is removed from the bloodstream by a combination of metabolism, excretion, and evaporation. 90-98% of ingested ethanol is metabolized into carbon dioxide and water. Around 5 to 10% of ethanol that is ingested is excreted unchanged in urine, breath, and sweat. Transdermal alcohol that diffuses through the skin as insensible perspiration or is exuded as sweat (sensible perspiration) can be detected using wearable sensor technology such as SCRAM ankle bracelet or the more discreet ION Wearable. Ethanol or its metabolites may be detectable in urine for up to 96 hours (3–5 days) after ingestion. Unlike most physiologically active materials, in typical recreational use, ethanol is removed from the bloodstream at an approximately constant rate (linear decay or zero-order kinetics), rather than at a rate proportional to the current concentration (exponential decay with a characteristic elimination half-life). This is because typical doses of alcohol saturate the enzymes' capacity. In Widmark's model, the elimination rate from the blood, β, contributes 60% of the uncertainty. Similarly to ρ, its value depends on the units used for blood. β varies 58% by occasion and 42% between subjects; it is thus difficult to determine β precisely, and more practical to use a mean and a range of values. Typical elimination rates range from 10 to 34 mg/dL per hour, with Jones recommending the range 0.10 - 0.25 g/L/h for forensic purposes, for all subjects.
=== 16 January === Senior US officials reported that the SAF had recently used chemical weapons against the RSF in rural areas at least twice. The US also sanctioned SAF chief General Abdel Fattah al-Burhan for the army's conduct in the war. The RSF said that it attacked fighters and vehicles in Kabkabiya belonging to the JDF between the SLM-Al Nur and the GSLF. The RSF called for a joint committee to investigate the incident.
Sources: en.wikipedia.org
=== Lanthipeptides === Lanthipeptides are one of the most well-studied families of RiPPs. The family is characterized by the presence of lanthionine (Lan) and 3-methyllanthionine (MeLan) residues in the final natural product. There are four major classes of lanthipeptides, delineated by the enzymes responsible for installation of Lan and MeLan. The dehydratase and cyclase can be two separate proteins or one multifunctional enzyme. Previously, lanthipeptides were known as "lantipeptides" before a consensus was reached in the field. Lantibiotics are lanthipeptides that have known antimicrobial activity. The founding member of the lanthipeptide family, nisin, is a lantibiotic that has been used to prevent the growth of food-born pathogens for over 40 years.
2 H3N+CH2COO− → H3N+CH2CONHCH2COO− + H2O Pyrolysis of glycine or glycylglycine gives 2,5-diketopiperazine, the cyclic diamide. Glycine forms esters with alcohols. They are often isolated as their hydrochloride, such as glycine methyl ester hydrochloride. Otherwise, the free ester tends to convert to diketopiperazine.
Spongin, a modified type of collagen protein, forms the fibrous skeleton of most organisms among the phylum Porifera, the sponges. It is secreted by sponge cells known as spongocytes. Spongin gives a sponge its flexibility. True spongin is found only in members of the class Demospongiae. Its molecular structure remains incompletely characterized, however it shares similarities with both collagen and keratin.
Ehlers–Danlos syndromes (EDS) are a group of 13 genetic connective tissue disorders. Symptoms often include loose joints; joint pain; stretchy, velvety skin; and abnormal scar formation. These may be noticed at birth or in early childhood. Complications may include aortic dissection, joint dislocations, scoliosis, chronic pain, or early osteoarthritis. The existing classification was last updated in 2017, when a number of rarer forms of EDS were added. EDS occurs due to mutations in one or more of the 19 particular genes which can contribute to the condition. The specific gene affected determines the type of EDS, though the genetic causes of hypermobile Ehlers–Danlos syndrome (hEDS) are still unknown. Some cases result from a new variation occurring during early development. In contrast, others are inherited in an autosomal dominant or recessive manner. Typically, these variations result in defects in the structure or processing of the protein collagen or tenascin. Diagnosis is often based on symptoms, particularly hEDS, but people may initially be misdiagnosed with somatic symptom disorder, depression, or myalgic encephalomyelitis/chronic fatigue syndrome. Genetic testing can be used to confirm all types of EDS except hEDS, for which a genetic marker has yet to be discovered. A cure is not yet known, and treatment is supportive in nature. Physical therapy and bracing may help strengthen muscles and support joints.
Fluorine-18 (18F, also called radiofluorine) is a fluorine radioisotope which is an important source of positrons. Its half-life is 109.734 minutes, less than two hours, and one of the shortest of radioisotopes with use outside research. It decays by positron emission 96.7% of the time and electron capture 3.3% of the time. Both modes of decay yield stable oxygen-18.
Sources: en.wikipedia.org
Cardarine is a common name for the investigational compound GW501516. It acts as a PPARδ agonist and is not approved for human use. It is prohibited in sport.
It activates PPARδ, a nuclear receptor that influences gene expression related to lipid and energy metabolism. Animal studies show changes in endurance and lipid levels. Human effects and risks are not well established.
No, cardarine is not a steroid. It belongs to a different chemical class, the PPARδ agonists. It is also not a selective androgen receptor modulator.
Cardarine is a common name for GW501516, a synthetic PPARδ agonist. It is not a steroid or a selective androgen receptor modulator. It was developed and studied as a research compound for metabolic pathways.