Everything below concerns fatty acid oxidation. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-12-28. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
Safety discussions about cardarine frequently cite rodent carcinogenicity findings reported in the 2000s. In those studies, treated animals developed tumors at multiple sites, leading sponsors to discontinue clinical development. The relevance of these findings to humans has not been resolved, but they are a major reason the compound is not approved. Current literature emphasizes uncertainty about long-term effects and the risks of unregulated use. Regulators and health agencies have not established a safe human exposure level.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white solid | Typical form of reference material |
| Solubility | Low in water; soluble in DMSO | Used to prepare stock solutions |
| Typical storage | -20 °C, desiccated, protected from light | Common laboratory practice |
| Analytical method | LC-MS/MS | Detects parent compound and metabolites |
| Common test matrix | Urine or blood | Used in anti-doping analysis |
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.
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.
Cardarine is prohibited in competitive sport under the World Anti-Doping Agency code, where it is classified as a metabolic modulator. It is not approved as a prescription medicine in the United States, European Union, or other major markets. Regulatory action has focused on its presence in sports and in products marketed as research chemicals. Because it has no accepted medical indication, supply is often unregulated. This status creates legal and safety uncertainties for anyone who encounters the substance.
=== Diffusive === Some materials may merge at the joint by diffusion. This may occur when the molecules of both materials are mobile and soluble in each other. This would be particularly effective with polymer chains where one end of the molecule diffuses into the other material. It is also the mechanism involved in sintering. When metal or ceramic powders are pressed together and heated, atoms diffuse from one particle to the next. This joins the particles into one.
== Research == A wave of enthusiasm for secretin as a possible treatment for autism arose in the 1990s based on a hypothetical gut-brain connection; as a result the NIH ran a series of clinical trials that showed that secretin was not effective, which brought an end to popular interest. A high-affinity and optimized secretin receptor antagonist (Y10,c[E16,K20],I17,Cha22,R25)sec(6-27) has been designed and developed which has allowed the structural characterization of secreting inactive conformation.
Flashbacks are psychological episodes where individuals re-experience some of LSD's subjective effects after the drug has worn off, persisting for days or months post-hallucinogen use. These experiences are associated with hallucinogen persisting perception disorder (HPPD), where flashbacks occur intermittently or chronically, causing distress or functional impairment. The etiology of flashbacks is varied. Some cases are attributed to somatic symptom disorder, where individuals fixate on normal somatic experiences previously unnoticed before drug consumption. Other instances are linked to associative reactions to contextual cues, similar to responses observed in individuals with past trauma or emotional experiences. The risk factors for flashbacks remain unclear, but pre-existing psychopathologies may be significant contributors. Estimating the prevalence of HPPD is challenging. It is considered rare, with occurrences ranging from 1 in 20 users experiencing the transient and less severe type 1 HPPD, to 1 in 50,000 for the more concerning type 2 HPPD. Contrary to internet rumors, LSD is not stored long-term in the spinal cord or other parts of the body. Pharmacological evidence indicates LSD has a half-life of 175 minutes and is metabolized into water-soluble compounds like 2-oxo-3-hydroxy-LSD, eliminated through urine without evidence of long-term storage. Clinical evidence also suggests that chronic use of SSRIs can potentiate LSD-induced flashbacks, even months after stopping LSD use.
Mn(CO)5Cl + AlCl3 + CO → [Mn(CO)+6][AlCl−4] The use of strong acids succeeded in preparing gold carbonyl cations such as [Au(CO)2]+, which is used as a catalyst for the carbonylation of alkenes. The cationic platinum carbonyl complex [Pt(CO)4]2+ can be prepared by working in so-called superacids such as antimony pentafluoride. Although CO is considered generally as a ligand for low-valent metal ions, the tetravalent iron complex [Cp*2Fe]2+ (16-valence electron complex) quantitatively binds CO to give the diamagnetic Fe(IV)-carbonyl [Cp*2FeCO]2+ (18-valence electron complex).
== Technology == MA/MH technology is achieved by combining proprietary blends of polymers to obtain the desired MVTR and then manipulating the oxygen (O2) and carbon dioxide (CO2) transmission rates of the polymer by laser and/or mechanical microperforations. The result is a film which is tailored to provide the optimum modified atmosphere and modified humidity for the produce to be packaged. "Film composition and extent of microperforation are tailored in accordance with the respiratory activity and weight of the produce packaged, anticipated temperature fluctuations during storage and shipment, and expected physiological and pathological responses of the produce to CO2/O2 concentrations and humidity levels inside the package. ... [MA/MH] packaging allow[s] the formation of a desirable modified atmosphere, retarding ripening and senescence of the produce. Additional beneficial effects ... include reduction of decay, chilling injury, leaf elongation, leaf sprouting, tissue discoloration, peel blemishes, and formation of off-odors, and inhibition of bacterial growth on the produce surface."
Sources: en.wikipedia.org
== Discovery == Aerographene was discovered in 2013 at Zhejiang University by a team of scientists led by Gao Chao. He and his team had already successfully created macroscopic materials made out of graphene. These materials were one-dimensional and two-dimensional. However, when synthesizing aerographene, the scientists instead created a three-dimensional structure. The synthesis was accomplished by the freeze-drying of carbon nanotube solutions and large amounts of graphene oxide. Residual oxygen was then removed chemically.
An immigration stamp is an inked impression in a passport or other travel document, typically made by a rubber stamp upon entering or exiting a territory. Depending on the jurisdiction, a stamp can serve different purposes. For example, in the United Kingdom, an immigration stamp in a passport includes the formal leave to enter granted to a person subject to entry control. In other countries, a stamp activates or acknowledges the continuing leave conferred in the passport bearer's entry clearance. Under the Schengen system, a foreign passport is stamped with a date stamp which does not indicate any duration of stay. This means the person is deemed to have permission to remain for either 3 months or the period shown on their visa, if specified otherwise. Member states of the European Union are not permitted to place a stamp in the passport of a person who is not subject to immigration control. Stamping is prohibited because it imposes a control to which the person is not subject. Passport stamps may occasionally take the form of sticker stamps, such as entry stamps from Japan. Depending on nationality, a visitor may not receive a stamp at all (unless specifically requested), such as an EU or EFTA citizen travelling to an EU or EFTA country, Albania, or North Macedonia. Most countries issue exit stamps in addition to entry stamps. A few countries issue only entry stamps, including Canada, El Salvador, Ireland, Mexico, New Zealand, Singapore, United Kingdom and the United States of America.
At least 18 microbial VOCs (MVOCs) have been characterized including 1-octen-3-ol (mushroom alcohol), 3-Methylfuran, 2-pentanol, 2-hexanone, 2-heptanone, 3-octanone, 3-octanol, 2-octen-1-ol, 1-octene, 2-pentanone, 2-nonanone, borneol, geosmin, 1-butanol, 3-methyl-1-butanol, 3-methyl-2-butanol, and thujopsene. The last four are products of Stachybotrys chartarum, which has been linked with sick building syndrome.
The digital ion trap (DIT) is an quadrupole ion trap driven by digital signals, typically in a rectangular waveform, generated by switching rapidly between discrete DC voltage levels. The digital ion trap has been mainly developed as a mass analyzer.
Sources: en.wikipedia.org
==== Steroids ==== The hypothalamus contains neurons that react strongly to steroids and glucocorticoids (the steroid hormones of the adrenal gland, released in response to ACTH). It also contains specialized glucose-sensitive neurons (in the arcuate nucleus and ventromedial hypothalamus), which are important for appetite. The preoptic area contains thermosensitive neurons; these are important for TRH secretion.
Chart of the Nuclides 2014 (Japan Atomic Energy Agency) Interactive Chart of Nuclides (Brookhaven National Laboratory) Karlsruhe Nuclide Chart – New 10th edition 2018 Nucleonica web driven nuclear science IAEA Live Chart of Nuclides app for mobiles: Android or Apple – for PC use The Live Chart of Nuclides - IAEA The Colourful Nuclide Chart, by Edward Simpson of Australian National University Nuclide chart (EnergyEducation.ca) Another example of a Chart of Nuclides from Korea Data up to Jan 1999 only
The affinity of metal ions for ligands is described by a stability constant, also called the formation constant, and is represented by the symbol Kf. It is the equilibrium constant for its assembly from the constituent metal and ligands, and can be calculated accordingly, as in the following example for a simple case:
=== Legal status === On 24 February 2022, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Kapruvia, intended for treatment of moderate-to-severe pruritus associated with chronic kidney disease. The applicant for this medicinal product is Vifor Fresenius Medical Care Renal Pharma France. Difelikefalin was approved for medical use in the European Union in April 2022.
=== Early observational studies === From the 1890s onwards, associations of tobacco use with cancers and vascular disease were regularly reported. In 1930, Fritz Lickint of Dresden, Germany, published a meta-analysis citing 167 other works to link tobacco use to lung cancer. Lickint showed that people with lung cancer were likely to be smokers. He also argued that smoking tobacco was the best way to explain the fact that lung cancer struck men four or five times more often than women (since women smoked much less), and discussed the causal effect of smoking on cancers of the liver and bladder.
Sources: en.wikipedia.org
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.
PPARδ is a nuclear receptor that regulates genes linked to fatty acid oxidation and energy metabolism. Activation can alter lipid handling and energy use in experimental models. The full range of effects in humans is still under study.
The solid compound is generally stable when kept cold, dry, and protected from light. Solutions may degrade faster, so laboratory protocols often specify fresh preparation or cold storage. Stability can depend on solvent, concentration, and container.
Cardarine is an investigational synthetic compound that acts as a PPARδ agonist. It is also known as GW501516 and has been studied mainly in preclinical research. It is not an approved medicine.