Everything below concerns Mass spectrometry. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-04-02. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Primary target | PPARδ (NR1C2) | Nuclear receptor involved in lipid metabolism |
| Preclinical effect | Increased fatty acid oxidation | Observed in rodent studies |
| Key safety signal | Tumors in rodents after long-term exposure | Contributed to halted clinical development |
| Human trial status | No approved product; development stopped | Limited short-term metabolic data |
| Sport regulatory status | Prohibited at all times | WADA hormone and metabolic modulators class |
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.
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.
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.
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.
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.
Food and Drug Administration (FDA), the United States Department of Agriculture (USDA), United Nations University (UNU) and the United States National Academy of Sciences when judging the quality of protein in the human is not PER or BV but the Protein Digestibility Corrected Amino Acid Score (PDCAAS), as it is viewed as accurately measuring the correct relative nutritional value of animal and vegetable sources of protein in the diet.
The shortage of manufacturing facilities for the Il-86 was a problem from the outset: "The rapid modernisation of the Soviet Air Force ... has left limited scope for the expansion of commercial production ... the lack of production capacity is being remedied partly by ... international cooperation." This meant involving the Polish aircraft industry in the project.
=== 1980s === 1982: Nephrologist Leah Lowenstein became the first woman dean of a co-educational medical school in the United States. 1983: Barbara McClintock received the Nobel Prize in Physiology or Medicine for her discovery of genetic transposition; she was the first woman to receive that prize without sharing it, and the first American woman to receive any unshared Nobel Prize. 1984: Kathryn D. Sullivan becomes the first American woman to walk in space. 1988: Patricia Bath was the first African American woman to receive a medical patent, which was her invention of laser cataract treatment. 1988: Gertrude B. Elion received the Nobel Prize in Physiology or Medicine along with James W. Black and George H. Hitchings "for their discoveries of important principles for drug treatment".
At low enough temperatures, a distinction can be made between the axial and equatorial hydrogens in cyclohexane. An example of nuclear magnetic resonance being used in the determination of a structure is that of buckminsterfullerene (often called "buckyballs", composition C60). This now famous form of carbon has 60 carbon atoms forming a sphere. The carbon atoms are all in identical environments and so should see the same internal H field. Unfortunately, buckminsterfullerene contains no hydrogen and so 13C nuclear magnetic resonance has to be used. 13C spectra require longer acquisition times since carbon-13 is not the common isotope of carbon (unlike hydrogen, where 1H is the common isotope). However, in 1990 the spectrum was obtained by R. Taylor and co-workers at the University of Sussex and was found to contain a single peak, confirming the unusual structure of buckminsterfullerene.
=== Binding === DCBQ is an electrophilic compound, so it can bind in the human body to multiple nucleophilic compounds. DCBQ can, for instance, react with GSH, substituting the Cl groups for the GS group. DCBQ is thus being dechlorinated and can undergo Michael addition with GSH, resulting in more glutathionylated products. The second Cl group can also be removed from the compound when reacting with another GSH molecule. DCBQ can also undergo redox reactions when reacting with an electron, forming radicals. These radicals can also react with GSH, forming more conjugation products. DCBQ can also react with amino acids. When DCBQ was brought in contact with amino acids, the DCBQ was quickly removed, suggesting that the DCBQ reacted with the amino acids. DCBQ binds to the DNA via H-bonds, a non-covalent interaction. Because of its hydrophobicity, DCBQ might be intercalated between nucleotides in a double-stranded DNA molecule [source]. This intercalation might lead to increased access to the nucleotides, possibly leading to even more oxidative damage in the DNA. Amino acids can also covalently bind to DCBQ. The amino acids undergo nucleophilic substitution with both DCBQ and DCBQ-OH, the product of DCBQ hydrolysis. Proteins can be bound by DCBQ covalently via cysteine or lysine residues. Catechins, which are naturally present in for instance green tea, can competitively bind to DCBQ, reducing the amount of proteins bound to DCBQ [16]. The proteins are covalently modified when bound to DCBQ, which might change the stability and alter the function of the protein.
Sources: en.wikipedia.org
==== PROSITE pattern notation ==== The PROSITE notation uses the IUPAC one-letter codes and conforms to the above description with the exception that a concatenation symbol, '-', is used between pattern elements, but it is often dropped between letters of the pattern alphabet. PROSITE allows the following pattern elements in addition to those described previously:
=== Other === Some people with aphantasia have been reported to have acquired visual mental imagery after using psychedelics. While enhanced mental imagery may seem appealing, it may also pose risks such as increased risk of psychiatric disorders.
Typically two to four units of O negative blood are used in these situations, since they are unlikely to cause a reaction. A potentially fatal reaction is possible if the recipient has pre-existing antibodies, and uncross matched blood is only used in dire circumstances. Since O negative blood is not common, other blood types may be used if the situation is desperate.
Drostanolone propionate produces considerably less virilization in women compared to equal doses of testosterone propionate. However, since the given dosage for breast cancer was relatively high (200 mg/twice a week), mild virilization including oily skin, acne, voice deepening, hirsutism, and clitoral enlargement could still occur, and marked virilization could manifest with long-term therapy. The drug has no estrogenic activity and hence has no propensity for causing gynecomastia (in males) or fluid retention. Drostanolone propionate is not known to pose a risk of hepatotoxicity.
The DNA encoding a fusion of coat protein and protein of interest is often encoded on a phagemid - a plasmid containing both a bacterial origin of replication and phage attachment sequence. This allows it to be maintained and amplified in bacteria without producing phage virons. When bacterial colony reaches a desired size, a helper plasmid is transformed into the bacteria to supply them with the rest of the phage genome, enabling viron production. Alternatively, these phage genes can maintained within bacteria under inducible promoters, obviating the need for separate helper plasmid introduction.
Sources: en.wikipedia.org
Rodent studies reported increased endurance and fat oxidation after GW501516 exposure. Long-term studies also found higher rates of some tumors, which led to halted development.
Small short-term human trials examined metabolic markers such as lipids and glucose. The trials did not continue after rodent cancer findings, so long-term human safety is unknown.
Controlled human trials have not established a performance benefit. Anecdotal reports exist, but they are not reliable evidence.
Cardarine is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.