If you have been reading about carcinogenicity and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-07-18. Where a claim depends on a specific study, the study is described rather than over-claimed.
Quality assessment for cardarine samples usually combines identity, purity, and impurity testing. Nuclear magnetic resonance spectroscopy and mass spectrometry can confirm molecular structure, while high-performance liquid chromatography estimates purity. Certificates of analysis from testing laboratories may list these results, but they do not establish safety or legality. In the absence of approved manufacturing, products sold online may contain the wrong compound, variable amounts, or unlisted contaminants. Independent verification is therefore central to analytical work and to interpreting any reported biological activity.
Laboratory detection of GW501516 commonly uses liquid chromatography coupled with tandem mass spectrometry. The method can identify the parent compound or its metabolites in urine and blood after sample cleanup. Protein precipitation, solid-phase extraction, or enzymatic hydrolysis may precede analysis, depending on the matrix. Reference standards are required for accurate quantification and confirmation. Because the compound is not approved, testing often occurs in anti-doping, forensic, or research settings rather than routine clinical care. Results are reported with limits of detection and quantification.
Stability of GW501516 depends on form, temperature, light exposure, and moisture. Solid reference material is typically stored frozen or refrigerated in a desiccator and protected from light. Solutions in organic solvents such as dimethyl sulfoxide are often kept frozen in aliquots to reduce freeze-thaw cycling. Aqueous solubility is low, so aqueous stock solutions can be difficult to prepare without cosolvents. Degradation may appear as changes in chromatographic purity or mass spectral signal. Stability studies are needed to establish shelf life for any specific preparation.
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.
Published human data are sparse and mostly come from early-phase trials. Those studies examined short-term changes in lipids, glucose, and exercise capacity, but they were not large enough to establish efficacy or long-term safety. Some animal experiments reported increased running endurance, yet such findings do not prove a performance benefit in people. Anti-doping laboratories detect GW501516 and its metabolites in urine or blood using liquid chromatography-tandem mass spectrometry. Detection windows depend on dose, sample type, and individual metabolism. The method is sensitive enough to identify trace residues in tested samples.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Common for reference-grade material. |
| Solubility | Low in water | Dissolves in DMSO and some organic solvents. |
| Typical storage | -20 °C, desiccated | Protect from light and moisture. |
| Analytical method | LC-MS/MS | Used for trace detection in biological matrices. |
| Purity assessment | HPLC with UV detection | Often combined with NMR and mass spectrometry. |
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.
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.
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.
Cardarine is a common name for GW501516, also GW-1516, a synthetic compound developed as a peroxisome proliferator-activated receptor delta (PPARδ) agonist. It belongs to a class of agents that modulate gene transcription related to lipid and energy metabolism. The compound was studied in preclinical and early clinical research for metabolic and cardiovascular conditions, but it did not progress to approved therapeutic use. Its name appears in fitness and sports contexts despite not being approved as a 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.
Human trials of GW501516 were small and short in duration. They examined lipid levels, glucose handling, and other metabolic markers, but the programs were halted after the animal cancer findings. No approved therapeutic product exists, and published human data are insufficient for establishing long-term safety. Reports of use for athletic performance come mainly from non-clinical settings and cannot be verified through controlled trials. Independent testing of products sold as cardarine has found inconsistent purity and labeling.
Laboratory studies indicate that GW501516 activates PPARδ, a nuclear receptor involved in fatty acid oxidation and energy metabolism. In rodent experiments, treated animals often showed increased endurance and reduced fat mass. These effects were observed under controlled conditions and do not establish safe or effective use in humans. The exact dose-response relationship in humans remains poorly characterized. Species differences in metabolism can affect how results translate across animals and people.
Safety concerns emerged from long-term animal studies. In rodents given the compound for extended periods, researchers found an increased incidence of certain cancers, including liver and bladder tumors. These findings contributed to the discontinuation of clinical development. Whether similar risks apply to short-term or low-level exposure in humans is not established, and controlled human safety data are limited. The relevance of high-dose rodent carcinogenicity findings to human use remains a subject of debate.
Anti-doping laboratories identify GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the usual matrix, and detection can occur after the parent compound has cleared from blood. The exact detection window depends on dose, formulation, individual metabolism, and assay sensitivity. Because the compound is prohibited at all times, athletes are subject to testing in and out of competition. Analytical methods continue to improve as new metabolites and designer analogs are characterized.
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.
=== Other nervous system side effects === Nervous-system effects include insomnia, restlessness, and rarely, seizure, convulsions, and psychosis. Other rare and serious adverse events have been observed with varying degrees of evidence for causation.
Darkling Beetle/Mealworm Information. Center for Insect Science Education Outreach. University of Arizona. Mealworms and Darkling Beetles (Tenebrio beetle). Archived 2021-04-26 at the Wayback Machine FOSSweb.
== Signs and symptoms == Muscle dysfunction and weakness – This occurs in major muscles, but also may manifest as: diplopia, low cardiac output, dysphagia, and respiratory depression due to respiratory muscle weakness. Mental status changes – This may range from irritability to gross confusion, delirium, and coma. White blood cell dysfunction, causing worsening of infections. Instability of cell membranes due to low adenosine triphosphate (ATP) levels – This may cause rhabdomyolysis with increased serum levels of creatine phosphokinase, and also hemolytic anemia. Increased affinity for oxygen in the blood caused by decreased production of 2,3-bisphosphoglyceric acid. If hypophosphatemia is chronic; rickets in children or osteomalacia in adults may develop.
The legion was probably founded by Diocletian to help defend the Danube. I Pontica: the legion was founded by Dioceltian to help defend Pontus Polemoniacus. The legion was stationed in Trapezus. Legio II II Armeniaca II Britannica: comitatensis under Magister Peditum II Flavia Constantia: comitatensis under the command of the Magister Peditum II Flavia Virtutis: comitatensis under the command of the Magister Peditum II Herculia (devoted to Hercules): levied by Diocletian, stationed in Scythia Minor II Isaura II Iulia Alpina: pseudocomitatensis under the command of the Magister Peditum, in Comes Illyricum command. It was probably founded by Crispus or Constans. Its objective was to defend Alpes Cottiae II Felix Valentis Thebaeorum: comitatensis Legio III III Diocletiana III Flavia Salutis: comitatensis unit of the Late Roman Empire under the command of the Magister Militum in the west. The Legio III Flavia Salutis was raised by either Constantius II or Diocletian and was used to guard North Africa. III Herculea: comitatensis under the command of the Comes Illyricum III Isaura III Iulia Alpina: comitatensis under the command of the Magister Peditum command in Italy Legio IV IV Italica IV Martia IV Parthica Legio V V Iovia (maybe the Jovians) V Parthica Legio VI VI Gemella VI Gallicana VI Herculia (maybe the Herculians) VI Hispana VI Parthica Legio XII XII Victrix
=== Cancer === In 2007 reports emerged in the press and via the Internet that Evangelos Michelakis and coworkers at the University of Alberta had reported that sodium dichloroacetate reduced tumors in rats and killed cancer cells in vitro. Because the drug cannot be patented, financing the broad and expensive testing required to obtain FDA approval is problematic. The US Food and Drug Administration enforces the law that prohibits the sale of substances with the suggestion that they are cancer treatments unless they have been approved by the FDA. The American Cancer Society in 2012 stated that "available evidence does not support the use of DCA for cancer treatment at this time." Physicians warned of potential problems if people attempt to try DCA outside a controlled clinical trial. One problem with attempting this is obtaining the chemical. One fraudster was sentenced to 33 months in prison for selling a white powder containing starch, but no DCA, to people with cancer. The only monitored in vivo dosage of five human patients with glioblastoma with DCA was not designed to test its efficacy against their cancer. This study was rather to see whether it could be given at a specific dosage safely without causing side effects (e.g. neuropathy). All five patients were receiving other treatments during the study.
Sources: en.wikipedia.org
==== Serotonin ==== Amphetamine exerts analogous, yet less pronounced, effects on serotonin as on dopamine and norepinephrine. Amphetamine affects serotonin via VMAT2 inhibition and SERT phosphorylation. Like dopamine, amphetamine has low, micromolar affinity at the human 5-HT1A receptor.
, as in "Notation"), which are non-linear polynomial functions of δD and δ13C values. Such non-linearity can be a diagnostic signature for mixing if multiple samples of various mixing ratios can be measured. When end-members have similar δ13C or δD compositions, the non-linearity is negligible.
sGC expression has been shown to be highest in the striatum compared to other brain regions and has been explored as a possible candidate for restoring striatal dysfunction in Parkinson's disease. sGC acts as an intracellular intermediary for regulating dopamine and glutamate. Upregulation, which creates neuronal sensitivity, of the cGMP in a dopamine-depleted striatum has been associated with the symptoms of Parkinson's. Increased intracellular cGMP has been shown to contribute to excessive neuron excitability and locomotor activity. Activation of this pathway can also stimulate presynaptic glutamate release and cause an upregulation of AMPA receptors postsynaptically.
At least 90% of smallpox cases among unvaccinated persons were of the ordinary type. In this form of the disease, by the second day of the rash the macules had become raised papules. By the third or fourth day, the papules had filled with an opalescent fluid to become vesicles. This fluid became opaque and turbid within 24–48 hours, resulting in pustules. By the sixth or seventh day, all the skin lesions had become pustules. Between seven and ten days the pustules had matured and reached their maximum size. The pustules were sharply raised, typically round, tense, and firm to the touch. The pustules were deeply embedded in the dermis, giving them the feel of a small bead in the skin. Fluid slowly leaked from the pustules, and by the end of the second week, the pustules had deflated and began to dry up, forming crusts or scabs. By day 16–20 scabs had formed over all of the lesions, which had started to flake off, leaving depigmented scars. Ordinary smallpox generally produced a discrete rash, in which the pustules stood out on the skin separately. The distribution of the rash was most dense on the face, denser on the extremities than on the trunk, and denser on the distal parts of the extremities than on the proximal. The palms of the hands and soles of the feet were involved in most cases.
=== Open-chain form === An open-chain form of glucose makes up less than 0.02% of the glucose molecules in an aqueous solution at equilibrium. The rest is one of two cyclic hemiacetal forms. In its open-chain form, the glucose molecule has an open (as opposed to cyclic) unbranched backbone of six carbon atoms, where C-1 is part of an aldehyde group H(C=O)−. Therefore, glucose is also classified as an aldose, or an aldohexose. The aldehyde group makes glucose a reducing sugar giving a positive reaction with the Fehling test.
Sources: en.wikipedia.org
LC-MS/MS is common, often after sample cleanup. The assay targets GW501516 or its metabolites.
Reference material is usually kept cold, dry, and protected from light. Frozen aliquots reduce repeated freeze-thaw cycles.
No approved pharmaceutical product exists, so manufacturing and quality controls are not standardized. Products may contain different compounds or impurities.
Anti-doping and clinical laboratories commonly use liquid chromatography-tandem mass spectrometry. The method can identify GW501516 and its metabolites in urine or blood. Detection depends on sample timing and the amount present.