LC-MS/MS is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2025-09-01. Numbers and descriptions here follow the published literature rather than marketing material.
GW501516 acts on PPARδ, a nuclear receptor that helps regulate fatty acid oxidation and energy homeostasis. In animal studies, activation of this receptor was associated with increased endurance and changes in lipid metabolism. Human trials examined effects on blood lipids and other metabolic markers, but the compound did not advance to approval. Rodent studies later reported tumors in multiple tissues at doses used in those experiments. Whether those findings translate to human risk remains uncertain, and the clinical relevance of the animal data is still debated.
Regulatory bodies treat GW501516 as a prohibited substance in competitive sport. The World Anti-Doping Agency added it to the prohibited list, and it falls under classes covering metabolic modulators and hormone-related agents. It is not approved by drug regulators for human use, and it is not a lawful dietary supplement. Products sold under the cardarine name may contain unlisted ingredients or different compounds. Because no approved product exists, quality and identity are not guaranteed by pharmaceutical manufacturing standards.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Common name | Cardarine | Common internet and media name. |
| Research code | GW501516 | Also written GW-1516. |
| Drug class | PPARδ agonist | Not a selective androgen receptor modulator. |
| Development status | Discontinued | Clinical development halted after rodent cancer findings. |
| Regulatory status | Prohibited in sport | Listed by WADA; not approved as medicine. |
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.
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.
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.
Gender incongruence is marked and sustained Patient meets diagnostic criteria for gender incongruence prior to gender-affirming hormone treatment in regions where a diagnosis is necessary to access health care Patient has capacity to consent to hormone therapy treatment Other possible causes of apparent gender incongruence have been identified and excluded Mental health and physical conditions that could negatively impact the outcome of treatment have been assessed Understands the effect of gender-affirming hormone treatment on reproduction and they have explored reproductive options The WPATH standards of care distinguish between gender-affirming hormone therapy, and hormone replacement therapy, with the latter referring to the replacement of endogenous hormones after a gonadectomy to prevent cardiovascular and musculoskeletal issues.
== Release == The film premiered at the 62nd Cannes Film Festival on 18 May 2009, and went on to screen at festivals such as the Toronto International Film Festival and the Maryland Film Festival. It was released in Greece on 11 November 2009 by Feelgood Entertainment. Verve Pictures acquired distribution rights for the United Kingdom and released it on 23 April 2010. Kino International released it in the United States on 25 June 2010.
=== Ultraviolet lens === A hyperlens is a real-time super-resolution lens that can transform evanescent waves into propagating waves and thus break the diffraction limit. In 2016 a hyperlens based on dielectric layered graphene and h-boron nitride (h-BN) can surpass metal designs. Based on its anisotropic properties, flat and cylindrical hyperlenses were numerically verified with layered graphene at 1200 THz and layered h-BN at 1400 THz, respectively. In 2016 a 1-nm thick graphene microlens that can image objects the size of a single bacterium. The lens was created by spraying a sheet of graphene oxide solution, then molding the lens using a laser beam. It can resolve objects as small as 200 nanometers, and see into the near infrared. It breaks the diffraction limit and achieve a focal length less than half the wavelength of light. Possible applications include thermal imaging for mobile phones, endoscopes, nanosatellites and photonic chips in supercomputers and superfast broadband distribution.
Sources: en.wikipedia.org
=== Organic carbon === The removal of organic carbon from water is one of the differentiators between deionized water and ultrapure water. Sources include bacteria, leaching from plastic piping, and dissolved atmospheric sources. Organic carbon can be removed using filtration by activated carbon and oxidation of organic carbon to carbon dioxide/bicarbonate.
=== Distinguishing anatomical features === While recent discoveries have made it more difficult to present a universally agreed-upon list of their distinguishing features, nearly all dinosaurs discovered so far share certain modifications to the ancestral archosaurian skeleton, or are clearly descendants of older dinosaurs showing these modifications. Although some later groups of dinosaurs featured further modified versions of these traits, they are considered typical for Dinosauria; the earliest dinosaurs had them and passed them on to their descendants. Such modifications, originating in the most recent common ancestor of a certain taxonomic group, are called the synapomorphies of such a group.
He was suspicious of the Soviet Union's motives in supporting African liberation movements, relating that "Russia is as imperialistic as America", although he acknowledged that "in the eyes of the Third World they have a cleaner slate". He also acknowledged that the material assistance provided by the Soviets was "more valuable" to the anti-apartheid cause than the "speeches and wrist-slapping" provided by Western governments. He was cautious of the possibility of a post-apartheid South Africa getting caught up in the imperialist Cold War rivalries of the United States and the Soviet Union.
Sources: en.wikipedia.org
== Theory == There are just 230 different ways of arranging objects in regular three-dimensional arrays. In molecular crystallography, these arrangements are called 'space groups'. However, only 65 of these arrangements are accessible to chiral objects or chiral molecules. The remaining 165 space groups contain either a center of symmetry or a mirror plane and are thus not accessible to natural globular proteins, which are chiral molecules. Wukowitz and Yeates developed a mathematical theory to explain the preference of globular proteins to crystallize in certain space groups. They suggested the preferred space group was determined by the number of degrees of freedom (D) or dimensionality as a measure of the ease with which a given symmetry can be formed. They analyzed the number of degrees of freedom for both chiral and achiral space groups where it was found that the space group P1(bar) with D=8 is theoretically the most dominant space group. Since the achiral space group had a higher degree of freedom compared to the chiral space groups, they predicted that racemic mixtures of protein enantiomers would crystallize more readily compared to the natural L-proteins alone by forming achiral {L-protein plus D-protein} pairs. While space group P1(bar) is most preferred, P21/c and C2/c are also highly preferred, whereas the other achiral space groups are expected to appear less frequently. Hence, P1(bar), P21/c, and C2/c are considered common centrosymmetric space groups in racemic mixtures.
An adult's trachea has an inner diameter of about 1.5 to 2 centimetres (1⁄2 to 3⁄4 in) and a length of about 10 to 11 cm (4 to 4+1⁄4 in), wider in males than females. The trachea begins at the lower edge of the cricoid cartilage of the larynx at the level of sixth cervical vertebra (C6) and ends at the carina, the point where the trachea branches into left and right main bronchi., at the level of the fourth thoracic vertebra (T4), although its position may change with breathing. The trachea is surrounded by 16–20 rings of hyaline cartilage; these 'rings' are 4 millimetres high in the adult, incomplete and C-shaped. Ligaments connect the rings. The trachealis muscle connects the ends of the incomplete rings and runs along the back wall of the trachea. Also adventitia, which is the outermost layer of connective tissue that surrounds the hyaline cartilage, contributes to the trachea's ability to bend and stretch with movement. Although trachea is a midline structure, it can be displaced normally to the right by the aortic arch.
== Chemistry == Tertiapin peptide is composed of 21 amino acids with the sequence: Ala-Leu-Cys-Asn-Cys-Asn-Arg-Ile-Ile-Ile-Pro-His-Met-Cys-Trp-Lys-Lys-Cys-Gly-Lys-Lys. The methionine residue is sensitive to oxidation, reducing the ability to block the ionic channels. Methionine can be substituted by glutamine in order to prevent the oxidation. The new synthesized peptide is named Tertiapin-Q and does not show any functional change as compared to the original peptide, which makes it a more suitable research tool.
== Distribution and habitat == Psilocybe cubensis is a pan-tropical species, occurring in the Gulf Coast states and southeastern United States, Mexico, in the Central American countries of Belize, Costa Rica, Panamá, El Salvador and Guatemala, the Caribbean countries Cuba, the Dominican Republic, Puerto Rico, Guadalupe, Martinique, and Trinidad, in the South American countries of Argentina, Bolivia, Brazil, Colombia, French Guiana, Paraguay, Uruguay and Peru, Southeast Asia, including Thailand, Vietnam, Cambodia and Malaysia, India, Australia, Fiji, and possibly Nepal and Hawaii. Psilocybe cubensis is found on cow (and occasionally horse) dung, sugar cane mulch or rich pasture soil, with mushrooms appearing from February to December in the northern hemisphere, and November to April in the southern hemisphere. In Asia, the species grows on water buffalo dung. Along with other fungi that grow on cow dung, P. cubensis is thought to have colonized Australia with the introduction of cattle there, 1800 of which were on the Australian mainland by 1803—having been transported there from the Cape of Good Hope, Kolkata and the American west coast. In Australia, the species grows between northern Queensland to southern New South Wales. In March 2018, several Psilocybe cubensis specimens were collected in Zimbabwe in the Wedza District of Mashonaland East province, approx. 120 km southeast of Harare. This was the first reported occurrence of a psilocybin mushroom in Zimbabwe.
Sources: en.wikipedia.org
No. Cardarine is a PPARδ agonist, while selective androgen receptor modulators act on androgen receptors. The two classes differ in receptor target and downstream effects.
Preclinical rodent studies reported cancers, including liver and bladder tumors, at tested doses. The human relevance of those findings is uncertain, but development was discontinued. No approved human product resulted.
No. It remains an investigational compound without approved therapeutic labeling. Sports regulators prohibit its use, and health agencies have warned against consuming it.
It binds to and activates PPAR delta, a nuclear receptor that controls expression of genes related to fatty acid oxidation. This mechanism can alter energy metabolism in animal models. It is not a direct stimulant or fat-burning enzyme.