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 2026-05-29. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Cardarine is a common name for GW501516, a synthetic compound developed in the 1990s through research collaborations involving GlaxoSmithKline. It belongs to a class of molecules known as peroxisome proliferator-activated receptor delta agonists. Early studies explored its effects on lipid metabolism and energy expenditure in animal models. The compound was never approved as a human medicine, and clinical development was discontinued. In the years since, it has appeared in fitness and bodybuilding communities as a performance-enhancing substance. Regulatory agencies classify it as an unapproved drug.
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.
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 |
|---|---|---|
| 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. |
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.
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.
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
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.
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.
Damage-associated molecular patterns (DAMPs) are molecules within cells that are a component of the innate immune response released from damaged or dying cells due to trauma or an infection by a pathogen. They are also known as danger signals, and alarmins because they serve as warning signs to alert the organism to any damage or infection to its cells. DAMPs are endogenous danger signals that are discharged to the extracellular space in response to damage to the cell from mechanical trauma or a pathogen. Once a DAMP is released from the cell, it promotes a noninfectious inflammatory response by binding to a pattern recognition receptor (PRR). Inflammation is a key aspect of the innate immune response; it is used to help mitigate future damage to the organism by removing harmful invaders from the affected area and start the healing process. As an example, the cytokine IL-1α is a DAMP that originates within the nucleus of the cell which, once released to the extracellular space, binds to the PRR IL-1R, which in turn initiates an inflammatory response to the trauma or pathogen that initiated the release of IL-1α. In contrast to the noninfectious inflammatory response produced by DAMPs, pathogen-associated molecular patterns (PAMPs) initiate and perpetuate the infectious pathogen-induced inflammatory response. Many DAMPs are nuclear or cytosolic proteins with defined intracellular function that are released outside the cell following tissue injury.
Prenatal cocaine exposure (PCE) may occur when a pregnant woman uses cocaine. Under the former FDA pregnancy category system, cocaine was classified as a Category C drug. Its potential to cause harm to the fetus is not fully known, so it should only be administered to pregnant women if clearly necessary. Cocaine can act as a teratogen, having various effects on the developing fetus. Some common teratogenic defects caused by cocaine include hydronephrosis, cleft palate, polydactyly, and down syndrome. Cocaine as a drug has a low molecular weight and high water and lipid solubility which enables it to cross the placenta and fetal blood-brain barrier. Because cocaine is able to pass through the placenta and enter the fetus, the fetus' circulation can be negatively affected. With restriction of fetal circulation, the development of organs in the fetus can be impacted, even resulting in intestines developing outside of the fetus' body. Cocaine use during pregnancy can also result in obstetric labor complications such as, placental abruption, preterm birth or delivery, uterine rupture, miscarriage, and stillbirth. Prenatal cocaine exposure may cause subtle cognitive deficits and lower the chance of above-average IQ by age 4, but supportive caregiving can significantly improve outcomes.
=== Diseases === Interferon beta-1a and interferon beta-1b are used to treat and control multiple sclerosis, an autoimmune disorder. This treatment may help in reducing attacks in relapsing-remitting multiple sclerosis and slowing disease progression and activity in secondary progressive multiple sclerosis. Interferon therapy is used (in combination with chemotherapy and radiation) as a treatment for some cancers. This treatment can be used in hematological malignancy, such as in leukemia and lymphomas including hairy cell leukemia, chronic myeloid leukemia, nodular lymphoma, and cutaneous T-cell lymphoma. Patients with recurrent melanomas receive recombinant IFN-α2b. Both hepatitis B and hepatitis C can be treated with IFN-α, often in combination with other antiviral drugs. Some of those treated with interferon have a sustained virological response and can eliminate hepatitis virus in the case of hepatitis C. The most common strain of hepatitis C virus (HCV) worldwide—genotype I— can be treated with interferon-α, ribavirin and protease inhibitors such as telaprevir, boceprevir or the nucleotide analog polymerase inhibitor sofosbuvir. Biopsies of patients given the treatment show reductions in liver damage and cirrhosis. Control of chronic hepatitis C by IFN is associated with reduced hepatocellular carcinoma. A single nucleotide polymorphism (SNP) in the gene encoding the type III interferon IFN-λ3 was found to be protective against chronic infection following proven HCV infection and predicted treatment response to interferon-based regimens.
Tegileridine, sold under the brand name Aisute, is a drug which acts as a μ-opioid receptor agonist. It is closely related to compounds such as oliceridine, TRV734, and SHR9352, and shares a similar profile as a biased agonist selective for activation of the G protein signalling pathway over β-arrestin2 recruitment. In January 2024, tegileridine was approved in China under the brand name Aisute for the treatment of moderate to severe pain after abdominal surgery.
=== Human β-casomorphin 7 === Structure: YPFVQPI Despite human beta-casein having a A2-like "P" after "I", human colostrum and early lactation-stage milk contains significant amounts of hBCM7. It is a much weaker opioid and the FVQ sequence renders it susceptible to further degradation.
Sources: en.wikipedia.org
==== The suffixes "-holic" and "-holism" ==== In contemporary English, "-holic" is a suffix that can be added to a subject to denote an addiction to it. It was extracted from the word alcoholism (one of the first addictions to be widely identified both medically and socially) (correctly the root "alcohol" plus the suffix "-ism") by misdividing or rebracketing it into "alco" and "-holism". Terms formed this way, such as chocoholic and workaholic, are colloquial rather than diagnostic; the only behavioral addictions recognized in current diagnostic manuals are gambling disorder and gaming disorder.
== Alanine world hypothesis == Alanine is one of the twenty canonical α-amino acids used as building blocks (monomers) for the ribosome-mediated biosynthesis of proteins. Alanine is believed to be one of the earliest amino acids to be included in the genetic code standard repertoire. On the basis of this fact the "alanine world" hypothesis was proposed. This hypothesis explains the evolutionary choice of amino acids in the repertoire of the genetic code from a chemical point of view. In this model the selection of monomers (i.e. amino acids) for ribosomal protein synthesis is rather limited to those alanine derivatives that are suitable for building α-helix or β-sheet secondary structural elements. Dominant secondary structures in life as we know it are α-helices and β-sheets and most canonical amino acids can be regarded as chemical derivatives of alanine. Therefore, most canonical amino acids in proteins can be exchanged with alanine by point mutations while the secondary structure remains intact. The fact that alanine mimics the secondary structure preferences of the majority of the encoded amino acids is practically exploited in alanine scanning mutagenesis. In addition, classical X-ray crystallography often employs the polyalanine-backbone model to determine three-dimensional structures of proteins using molecular replacement—a model-based phasing method.
On 22 October, Trump said that he planned to also order strikes on land targets. The Wall Street Journal reported on 30 October 2025 that the US had identified land "targets that sit at the nexus of the drug gangs and the Maduro regime", including facilities such as ports and airstrips that the Venezuelan military allegedly uses for drug trafficking, without providing evidence to the press. Trump denied a Miami Herald report that the "Trump Administration [had] made the decision to attack military installations inside Venezuela". On 31 October 2025, Newsweek reported that US ships were positioned near the Venezuelan military base at La Orchila Island, "within immediate operational range for amphibious or precision strike missions". The US Southern Command posted videos of live-fire drills by US Marines; satellite imagery confirmed the location to be the USS Iwo Jima, situated less than 200 kilometres (120 mi) off the coast of Venezuela and accompanied by two other USS destroyers. The US State Department designated Cartel of the Suns a Foreign Terrorist Organization effective 24 November 2025. The Miami Herald wrote: "The designation would effectively label Maduro and senior officials, including Interior Minister Diosdado Cabello and Defense Minister Vladimir Padrino López, as terrorists." The Trump administration said the designation "allows the US military the ability to target Maduro's assets and infrastructure inside Venezuela". A phone call between Trump and Maduro, including Rubio, occurred later in November, according to The New York Times.
== Protein breakdown == Protein catabolism is the process by which proteins are broken down to their amino acids. This is also called proteolysis and can be followed by further amino acid degradation.
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.
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.