Everything below concerns PPAR delta. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-09-27. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Visual description for typical solid reference material. |
| Solubility | Poorly soluble in water; soluble in DMSO | Solubility depends on solvent, purity, and form. |
| Storage | Cool, dry, protected from light | Long-term storage often uses low temperature and desiccant. |
| Common analytical method | LC-MS/MS | Used for detection and quantification in biological matrices. |
| Common synonyms | GW-501516; GW501516; endurobol | Naming varies among literature, vendors, and databases. |
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
Analytical laboratories typically identify cardarine and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is a common matrix in anti-doping testing, while blood and tissue may be used in research settings. Detection windows depend on the assay, the sample matrix, and the compound's metabolism. Because cardarine is extensively metabolized, laboratories often target specific metabolites to improve sensitivity and confirmation. Reference standards are required for reliable quantification. Method validation includes checks for selectivity, linearity, and carryover.
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
Neuroendocrine tumors (NETs) are localised clinically using a range of DOTA based radiopharmaceuticals. For PET imaging these are typically Gallium-68 based. A commercial 64Cu-DOTA-TATE product has been FDA approved for localization of somatostatin receptor positive NETs since 2020.
=== Research environment === In the United States, research in digital agriculture is primarily funded by the National Institute of Food and Agriculture (NIFA) which comes under the US Department of Agriculture and to a lesser extent, by the National Science Foundation. Two large institutes applying IoT or artificial intelligence in digital agriculture have been unveiled by these funding organizations working together.
It may lead to brain tumors such as astrocytomas. In some of the late-onset neurodegenerative diseases that share aggregation of misfolded proteins as a common feature, such as Parkinson's disease and Alzheimer's disease, large insoluble aggregates of misfolded proteins can form and then result in neurotoxicity, through mechanisms that are not yet well understood. Decreased proteasome activity has been suggested as a cause of aggregation and Lewy body formation in Parkinson's. This hypothesis is supported by the observation that yeast models of Parkinson's are more susceptible to toxicity from α-synuclein, the major protein component of Lewy bodies, under conditions of low proteasome activity. Impaired proteasomal activity may underlie cognitive disorders such as the autism spectrum disorders, and muscle and nerve diseases such as inclusion body myopathy.
== Works == Macleod was a prolific writer. His first academic article was a paper on phosphorus content in muscles published in 1899. During his career he authored or co-authored over 200 papers and eleven books. Among them are:
Sources: en.wikipedia.org
As of May 2026, it is in preregistration for Freidreich's ataxia, phase 3 clinical trials for mitochondrial disorders, phase 2/3 trials for epilepsy, and phase 2 trials for Leigh disease, methylmalonic acidemia, noise-induced hearing loss, Parkinson's disease, and Rett syndrome, whereas no recent development has been reported for Tourette's syndrome.
== Overdose == The median lethal dose of THC in humans is not fully known as there is conflicting evidence. A 1972 study gave up to 90 mg/kg of THC to dogs and monkeys without any lethal effects. Some rats died within 72 hours after a dose of up to 36 mg/kg. A 2014 case study based on the toxicology reports and relative testimony in two separate cases gave the median lethal dose in humans at 30 mg/kg (2.1 grams THC for a person who weighs 70 kg; 154 lb; 11 stone), observing cardiovascular death in the one otherwise healthy subject of the two cases studied. A different 1972 study gave the median lethal dose for intravenous THC in mice and rats at 30–40 mg/kg. A 2020 fact sheet published by the US Drug Enforcement Administration stated that "no deaths from overdose of marijuana have been reported."
The 8.5 kg Mini- 11 and 25 kg Mini-12 can produce resolution mass spectra up to m/z 600, a range that makes it useful for studying metabolites, lipids, and other small molecules. The group also developed and incorporated a digital microfluidic platform to the MMS with the application to extract and quantify drugs in urine. Mini 12 can perform MS5 and analyze directly such complex samples as whole blood, untreated food, and environmental samples, without sample preparation or chromatographic separation.
== Pharmacokinetics == Lamivudine is well absorbed in the body and distributes widely into the extravascular space. Oral bioavailability is >80% and overall metabolism is insignificant where approximately 95% of the drug is found unchanged in the urine. The only known metabolite found in humans is trans-sulfoxide. The half-life of lamivudine is 10 to 15 hours and binds poorly to plasma proteins. Zidovudine is also well absorbed in the body and penetrates into the cerebrospinal fluid. Oral bioavailability is 75% and primarily metabolized by the liver by glucuronidation. The primary metabolite is GZDV, an inactive metabolite produced after first pass metabolism. The half-life of zidovudine is 0.5 to 3 hours and binds poorly to plasma proteins. Lamivudine and zidovudine are not extensively metabolized by CYP450 liver enzymes.
26 October In two studies, scientists report findings about the role of epigenetics – which is shaped during lifetime – in colorectal cancer, including that it is a major component of how an individual tumor varies and findings about its influences on the accumulation of DNA mutations and cancer phenotypes. At the 30th anniversary of the World Scientists' Warning to Humanity, scientists conclude that "We are now at 'code red' on planet Earth", facing a climate emergency, warning citizens and world leaders to take necessary actions with information about tracked "recent climate-related disasters, assess[ed] planetary vital signs, and [...] policy recommendations". A study concludes that cosmic radiation events in the tree-ring radiocarbon record called "Miyake events", don't appear to be caused by the solar cycle (i.e. solar flares) as thought previously and have extended durations. They occurred every ~1,000 years on average and may threaten global technologies this century. A magnetical guidance system with engineered bacterial microbots (see also 22 September above) for 'precision targeting' is demonstrated to be effective for fighting cancer in mice. 31 October Multiple traces of monkeypox are detected in non-sewered wastewater with sparse sampling from a densely populated metropolitan area in Asia. A new record for the longest-frozen embryos to ever result in a live birth is reported in the United States, with twins born after storage for 30 years.
Sources: en.wikipedia.org
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.
Most methods use liquid chromatography with tandem mass spectrometry. Urine is common in anti-doping testing, and blood or plasma may be used in research.
Typical guidance is cool, dry, dark storage, often at low temperature and with desiccant. Stability data are limited, so storage conditions should be verified for each batch or supplier.
It binds and activates PPARδ, a nuclear receptor that influences gene expression related to fatty acid metabolism and energy balance. This mechanism has been studied mainly in animals and cell models, not established as a safe human therapy.