LC-MS/MS raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-02-26. Anything still debated is marked as such rather than presented as settled.
PPARδ is a nuclear receptor that regulates gene expression related to fatty acid oxidation, glucose homeostasis, and mitochondrial function. GW501516 binds to this receptor with high affinity and activates downstream signaling in skeletal muscle and other tissues. Animal studies reported increased endurance and altered fuel preference, but human data remain limited and inconsistent. The precise relationship between receptor activation and observed physiological changes is still an area of active investigation. Researchers have also examined whether the compound affects inflammation or cell proliferation. No approved therapeutic indication exists for cardarine.
In laboratory settings, cardarine is studied as a tool compound for probing PPARδ biology. Published experiments often use cell cultures, rodent models, or isolated tissues. Some investigations focus on metabolic effects, while others assess potential risks such as carcinogenicity observed in long-term animal studies. Because human trials are sparse, most knowledge comes from preclinical work and adverse event reports. Scientific literature frequently notes the gap between animal findings and human outcomes. The compound is not a dietary supplement and is not intended for human consumption.
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.
Cardarine is a common name for GW501516, a synthetic compound first described in the 1990s as a selective agonist of the peroxisome proliferator-activated receptor delta. It was studied in preclinical models for metabolic and cardiovascular conditions, but it has not been approved as a medicine in the United States, Europe, or other major jurisdictions. Retail products labeled as cardarine are generally research chemicals or supplements, not pharmaceutical formulations. Because human safety and efficacy data remain limited, regulatory agencies treat it as an unapproved substance rather than a therapeutic product.
| Property | Value | Notes |
|---|---|---|
| CAS Registry Number | 317318-70-0 | Unique identifier for the compound. |
| Chemical class | PPARδ agonist | Synthetic ligand for peroxisome proliferator-activated receptor delta. |
| Appearance | White to off-white solid | Typical form of research-grade material. |
| Solubility | Soluble in DMSO and ethanol | Poorly soluble in water. |
| Typical storage | -20°C | Recommended for long-term storage of stock solutions. |
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.
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.
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.
== Early life == Princess Zita of Bourbon-Parma was born at the Villa Pianore in the Italian Province of Lucca, 9 May 1892. The unusual name Zita was given to her after Zita, a popular Italian saint who had lived in Tuscany in the 13th century. She was the third daughter and fifth child of the deposed Robert I, Duke of Parma, and his second wife, Infanta Maria Antonia of Portugal, a daughter of King Miguel of Portugal and his wife Adelaide of Löwenstein-Wertheim-Rosenberg. Zita's father had lost his throne as a result of the movement for Italian unification in 1859 when he was still a child. He fathered twelve children during his first marriage to Princess Maria Pia of the Two Sicilies (six of whom were mentally disabled, and three of whom died young). Duke Robert became a widower in 1882, and two years later he married Infanta Maria Antonia of Portugal. The second marriage produced a further twelve children. Zita was the 17th among Duke Robert's 24 children. Robert moved his large family between Villa Pianore (a large property located between Pietrasanta and Viareggio) and his Schwarzau Castle in Lower Austria. It was mainly in these two residences that Zita spent her formative years. The family spent most of the year in Austria, moving to Pianore in the winter and returning in the summer. To move between them, they took a special train with sixteen coaches to accommodate the family and their belongings.
4 Li + 2 SOCl2 → 4 LiCl + 1⁄8 S8 + SO2 These non-rechargeable batteries have advantages over other forms of lithium batteries such as a high energy density, a wide operational temperature range, and long storage and operational lifespans. They are popular power sources for IoT devices such as asset trackers and utility meters as well as military and aircraft emergency beacons. However, their high cost, non-rechargeability, and safety concerns have limited their use in consumer devices. The contents of the batteries are very corrosive, the SO2 is toxic by inhalation, and the batteries therefore require special disposal procedures; additionally, they may explode if shorted. The technology was used on the 1997 Sojourner Mars rover.
Cocaine use during pregnancy can affect a pregnant woman and her unborn baby in many ways. During the early months of pregnancy, it may increase the risk of miscarriage. Later in pregnancy, it can trigger preterm labor (labor that occurs before 37 weeks of pregnancy) or cause the baby to grow poorly. As a result, cocaine-exposed babies are more likely than unexposed babies to be born with low birth weight (less than 5.5 lb or 2.5 kg). Low-birthweight babies are 20 times more likely to die in their first month of life than normal-weight babies, and face an increased risk of lifelong disabilities such as mental retardation and cerebral palsy. Cocaine-exposed babies also tend to have smaller heads, which generally reflect smaller brains. Some studies suggest that cocaine-exposed babies are at increased risk of birth defects, including urinary tract defects and, possibly, heart defects. Cocaine also may cause an unborn baby to have a stroke, irreversible brain injury, or a myocardial infarction.
Both lancelets and lampreys have a primitive but functional interferon system that responds to their versions of interferons by upregulating gene similar to the well-known interferon-stimulated genes (LSGs) of land animals. The lamprey interferon receptor has also been identified as a heterodimer of the cytokine receptor family B (CRFB) family, much like in jawed vertebrates. By comparing the genome organizations of jawed fish, jawless fish, and lancelet, it was found that interferons arose by a duplication of interleukin 10 in a chordate ancestor to the vertebrates and the lancelets. By the time the bony fish (e.g. teleosts, tetrapods including humans) diverged from the cartilaginous fish (e.g. sharks), the duplication and specialization of interferon into types I, II (gamma), III (lambda), and IV had been complete. (This is known because types I, II, IV have been found in tetrapods, teleosts, and sharks, and that type III has been found in tetrapods and sharks.) Mammals, actually amniotes in general, are unlike the rest of the animal kingdom in that most of their type I IFNs are intronless, and are placed in a position not colinear with the other vertebrates. This is because the original type I IFN gene was copied in an intronless form (possibly by a retrotransposon acting on mRNA) to a new location between HACD4 and MTAP in a common ancestor of the amniotes, followed by a loss of the ancestral version.
costmary, 1–66 grams sweet flag, 20 grams hypericum, 8 grams Natural gum, 8 grams sagapenum, 8 grams acacia juice, 8 grams Illyrian iris (probably I. germanica), 8 grams cardamom, 8 grams anise, 12 grams Gallic nard (Valeriana italica), 16 grams gentian root, 16 grams dried rose leaves, 16 grams poppy-tears (Papaver rhoeas, a wild poppy with low opiate content), 17 grams parsley, 17 grams cassia, 20–66 grams saxifrage, 20–66 grams darnel, 20–66 grams long pepper, 20–66 grams storax, 21 grams castoreum, 24 grams frankincense, 24 grams hypocistis juice, 24 grams myrrh, 24 grams opopanax, 24 grams malabathrum leaves, 24 grams flower of round rush, 24–66 grams turpentine-resin, 24–66 grams galbanum, 24–66 grams Cretan carrot seeds, 24–66 grams nard, 25 grams opobalsam, 25 grams shepherd's purse, 25 grams rhubarb root, 28 grams saffron, 29 grams ginger, 29 grams cinnamon, 29 grams The ingredients are then "pounded and taken up in honey. Against poisoning, a piece the size of an almond is given in wine. In other affections an amount corresponding in size to an Egyptian bean is sufficient." Of these ingredients, Illyrian iris, darnel, and rhubarb were not commonly found in other versions of the antidote. However, Celsus' formulation, written 100 years after the death of Mithridates, was one of the first published. Galen called the antidote "theriac" and presented versions by Aelius (used by Julius Caesar), Andromachus (physician to Nero), Antipater, Nicostratus, and Damocratis. The Andromachus formulation closely resembles that of Celsus.
Sources: en.wikipedia.org
In October 2003, the People's Republic of China commenced its first crewed spaceflight, Shenzhou 5. The astronaut, Yang Liwei, brought along with him and ate specially processed yuxiang pork (Chinese: 鱼香肉丝), Kung Pao chicken (Chinese: 宫保鸡丁), and Eight Treasures rice (Chinese: 八宝饭), along with Chinese herbal tea. Food made for this flight and the subsequent crewed flight in 2007 has been commercialized for sale to the mass market. At Tiangong space station, meals consisting of 120 different types of food, selected based on astronauts' preferences, are stored aboard. Staples including shredded pork in garlic sauce, kung pao chicken, black pepper beef, yuxiang shredded pork, pickled cabbage, and beverages, including a variety of teas and juices, are resupplied by trips of the Tianzhou-class robotic cargo spacecraft. Fresh fruits and vegetables are stored in coolers. Huang Weifen, the chief astronaut trainer of CMSA, explains that most of the food is prepared to be solid, boneless, and in small pieces. Condiments such as pork sauce and Sichuan pepper sauce are used to compensate for the changes in the sense of taste in microgravity. Food items are often adjusted according to astronauts' feedback, such as when larger supplies of vegetables were included in Tianzhou 4. Additionally, China's Tiangong-2 station has conducted experiments growing food on board in a micro-gravity environment, such as thale cress, a form of edible weed, as well as rice.
On 4 June, Hezbollah rejected the truce deal announced the previous day and instead demanded a comprehensive truce and full withdrawal of Israel from Lebanon. On 19 June, an American official said that Israel and Hezbollah agreed to a truce mediated by the US, Qatar and Iran. On 26 June, US Secretary of State Marco Rubio announced a framework deal between Israel and Lebanon for "lasting peace and security" via US mediation. The agreement includes a cease-fire, requiring Hezbollah to end hostilities and withdraw from southern Lebanon, but it was subsequently rejected by Hezbollah.
The Asian Federation for Psychotherapy published a code of ethics in 2008 with the following principles: Beneficence, Responsibility, Integrity, Justices, and Respect. Similar to the APA code, it provides detailed instructions for the conduct of psychologists, specifically psychotherapists. Russia, India, Iran, Kazakhstan, China, Malaysia, and Japan are member countries. The National Latina/o Psychological Association adopted their current ethical guidelines in 2018, stating that "the traditional Eurocentric foundations in mainstream psychology have provided culturally bound knowledge about worldviews, ways of living, and cultural practices." Their principles are: Respect and Responsibility, Ethical Dilemmas, Ethical Decision-Making and Legal Responsibility, Consultation, Justice and Advocacy, Self-Awareness and Social-Consciousness, Action and Accountability, Training and Creating Infrastructure, and Mentorship.
Self-assembling peptides are a category of peptides which undergo spontaneous assembly into ordered nanostructures. Originally described in 1993, these designer peptides have attracted interest in the field of nanotechnology for their potential for application in areas such as biomedical nanotechnology, tissue cell culturing, molecular electronics, and more. Effectively self-assembling peptides act as building blocks for various material and device applications. The essence of this technology is to replicate what nature does: to use molecular recognition processes to form ordered assemblies of building blocks capable of conducting biochemical activities.
Sources: en.wikipedia.org
Sponges lack a digestive, circulatory, respiratory, or excretory system. Instead, they rely on the flow of water through their bodies to perform these functions. Many have adapted a hollow structure to facilitate the flow of water through their bodies. They typically feed by drawing in water through pores, filtering out small particles of food. They absorb oxygen dissolved in water, and they release carbon dioxide and nitrogenous waste into water that flows through them. Sponges can reproduce sexually and asexually. Asexual reproduction happens through a variety of mechanisms including by fragmentation, where a piece of the sponge splits off and reestablishes somewhere else. For sexual reproduction, most sponges are hermaphrodites, they produce both egg and sperm cells.
== Society and culture == EDS may have contributed to the virtuoso violinist Niccolò Paganini's skill, as he was able to play wider fingerings than a typical violinist. Many sideshow performers have EDS. Several of them were billed as the Elastic Skin Man, the India Rubber Man, and Frog Boy. They included such well-known individuals (in their time) as Felix Wehrle, James Morris, and Avery Childs. Two performers with EDS currently hold world records. Contortionist Daniel Browning Smith has hypermobile EDS and holds the current Guinness World Record for the most flexible man as of 2018, while Gary "Stretch" Turner, sideshow performer in the Circus Of Horrors, has held the current Guinness World Record for the most elastic skin since 1999, for his ability to stretch the skin on his stomach 6.25 inches.
=== Wound repair versus regeneration === An injury is an interruption of morphology and/or functionality of a given tissue. After injury, structural tissue heals with incomplete or complete regeneration. Tissue without an interruption to the morphology almost always completely regenerates. An example of complete regeneration without an interruption of the morphology is non-injured tissue, such as skin. Non-injured skin has a continued replacement and regeneration of cells which always results in complete regeneration. There is a subtle distinction between 'repair' and 'regeneration'. Repair means incomplete regeneration. Repair or incomplete regeneration, refers to the physiologic adaptation of an organ after injury in an effort to re-establish continuity without regards to exact replacement of lost/damaged tissue. True tissue regeneration or complete regeneration, refers to the replacement of lost/damaged tissue with an 'exact' copy, such that both morphology and functionality are completely restored. Though after injury mammals can completely regenerate spontaneously, they usually do not completely regenerate. An example of a tissue regenerating completely after an interruption of morphology is the endometrium; the endometrium after the process of breakdown via the menstruation cycle heals with complete regeneration. In some instances, after a tissue breakdown, such as in skin, a regeneration closer to complete regeneration may be induced by the use of biodegradable (collagen-glycoaminoglycan) scaffolds.
The basis of the chemical periodicity in the periodic table is the electron shell closure at each noble gas (atomic numbers 2, 10, 18, 36, 54, 86, and 118): as any further electrons must enter a new shell with higher energy, closed-shell electron configurations are markedly more stable, hence the inertness of noble gases. Protons and neutrons are also known to form closed nuclear shells, so the same happens at nucleon shell closures, which happen at specific nucleon numbers often dubbed "magic numbers". The known magic numbers are 2, 8, 20, 28, 50, and 82 for protons and neutrons, as well as 126 for neutrons. Nuclei with magic proton and neutron numbers, such as helium-4, oxygen-16, calcium-48, and lead-208, are "doubly magic" and relatively stable for their number of nucleons. This stability is very important for superheavy elements: with no stabilization, half-lives would be expected by exponential extrapolation to be nanoseconds at darmstadtium (element 110), because the ever-increasing electrostatic repulsion between protons overcomes the limited-range strong nuclear force that holds nuclei together. The next closed nucleon shells (magic numbers) are thought to denote the centre of the long-sought island of stability, where half-lives to alpha decay and spontaneous fission lengthen again.
== Medical uses == In the United States pioglitazone/glimepiride is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus who are already treated with a thiazolidinedione and sulfonylurea or who have inadequate glycemic control on a thiazolidinedione alone or a sulfonylurea alone. In the European Union pioglitazone/glimepiride is indicated for the treatment of people with type 2 diabetes mellitus who show intolerance to metformin or for whom metformin is contraindicated and who are already treated with a combination of pioglitazone and glimepiride.
Sources: en.wikipedia.org
Cardarine is a common name for GW501516, a synthetic PPARδ agonist developed for research. It has not been approved as a medication in any country. It is classified as an unapproved drug and a prohibited substance in sport.
No. Cardarine is not an anabolic steroid; it belongs to a different chemical class that targets PPARδ. Steroids act primarily through androgen receptors, while cardarine acts through a nuclear receptor involved in metabolism.
Some rodent studies reported increased endurance and changes in fat metabolism after cardarine exposure. Long-term studies in animals also raised concerns about cancer in certain tissues. Human trial data are limited, so these findings cannot be directly translated to people.
No. Major drug regulators have not approved GW501516 for treating any medical condition. Products sold as cardarine are typically unapproved research chemicals or supplements, so their contents and safety are not assured.