Cardarine comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-10-28. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Common for reference-grade material. |
| Solubility | Low in water | Dissolves in DMSO and some organic solvents. |
| Typical storage | -20 °C, desiccated | Protect from light and moisture. |
| Analytical method | LC-MS/MS | Used for trace detection in biological matrices. |
| Purity assessment | HPLC with UV detection | Often combined with NMR and mass spectrometry. |
A common misconception is that cardarine has been proven safe for human use. In reality, human clinical data are limited, and long-term animal studies have raised concerns about cancer. Another misconception is that it is a supplement or vitamin-like compound. It is a synthetic research chemical with no approved medical indication. Scientific discussion often focuses on its mechanism and detection rather than therapeutic use. Regulatory and anti-doping literature treats it primarily as a prohibited substance.
Cardarine is explicitly prohibited by the World Anti-Doping Agency under the class of PPARδ agonists. Its presence in urine or blood samples can be detected using mass spectrometry-based methods, often liquid chromatography-tandem mass spectrometry. Athletes who test positive may face sanctions, including bans from competition. The compound is also regulated as a prescription-only or unapproved drug in many countries. Enforcement varies by jurisdiction, and some regions treat it as a controlled substance. Online sales may occur despite these restrictions, creating quality and legal risks.
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.
Analytical laboratories typically identify cardarine and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is a common matrix in anti-doping testing, while blood and tissue may be used in research settings. Detection windows depend on the assay, the sample matrix, and the compound's metabolism. Because cardarine is extensively metabolized, laboratories often target specific metabolites to improve sensitivity and confirmation. Reference standards are required for reliable quantification. Method validation includes checks for selectivity, linearity, and carryover.
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
Cardarine is not approved for human therapeutic use in any major jurisdiction. It appears on the World Anti-Doping Agency Prohibited List as a PPARδ agonist within the hormone and metabolic modulators category. Sports organizations test for it because it has been detected in athlete samples and seized products. Regulatory actions against marketed research chemical versions have occurred in several countries, though enforcement varies. Availability through unregulated channels complicates oversight.
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.
== History == Hemoglobin was discovered as some sort of crystal formed from earthworm body fluid and animal blood by German biochemist Friedrich Ludwig Hünefeld at Leipzig University in 1840. When the protein nature was established another German Felix Hoppe-Seyler gave the name hemoglobin (literally "blood protein") in 1864. Its role as an oxygen transporter was later established. While studying sickle cell disease, Linus Pauling and Harvey Itano at the California Institute of Technology discovered in 1949 that the disease was due to abnormal hemoglobin, later called hemoglobin S (HbS). In 1950, Itano and James V. Neel discovered a slightly different case in which individuals had sickled red blood cells but not anemia. The hemoglobin was named hemoglobin III, but later known as hemoglobin C (HbC).
chiasma (pl.) chiasmata A cross-shaped junction that forms the physical point of contact between two non-sister chromatids belonging to homologous chromosomes during synapsis. As well as ensuring proper segregation of the chromosomes, these junctions are also the breakpoints at which chromosomal crossover may occur during mitosis or meiosis, which results in the reciprocal exchange of DNA between the synapsed chromatids.
This particular adaptation of the mixed economy, better known as the Nordic model, is characterised by more generous welfare states (relative to other developed countries) which are aimed specifically at enhancing individual autonomy, ensuring the universal provision of basic human rights and stabilising the economy. It is distinguished from other welfare states with similar goals by its emphasis on maximising labour force participation, promoting gender equality, egalitarian and extensive benefit levels, large magnitude of redistribution and expansionary fiscal policy. In the 1950s, popular socialism emerged as a vital current of the left in Nordic countries could be characterised as a democratic socialism in the same vein as it placed itself between communism and social democracy. In the 1960s, Gerhardsen established a planning agency and tried to establish a planned economy. Prominent Swedish Prime Minister Olof Palme identified himself as a democratic socialist. The Rehn–Meidner model was adopted by the Swedish Social Democratic Party in the late 1940s. This economic model allowed capitalists who owned very productive and efficient firms to retain excess profits at the expense of the firm's workers, exacerbating income inequality and causing workers in these firms to agitate for a better share of the profits in the 1970s. Women working in the state sector also began to assert pressure for better and equal wages.
=== Wound healing and fibrosis === In skin wound healing, CCN1 is highly expressed in the granulation tissue by myofibroblasts, which proliferate and rapidly synthesize ECM to maintain tissue integrity and to promote regeneration of parenchymal cells. However, excessive matrix deposition can lead to fibrosis, scarring, and loss of tissue function. In skin wounds, CCN1 accumulates in the granulation tissue as myofibroblasts proliferate, and eventually reaches a sufficiently high level to drive the myofibroblasts themselves into senescence, whereupon these cells cease to proliferate and express matrix-degrading enzymes. Thus, CCN1 limits synthesis and deposition of ECM by myofibroblasts, reducing the risk of fibrosis during wound healing. In addition to skin wound healing, CCN1 expression is elevated in remodeling cardiomyocytes after myocardial infarction, in vascular injury, and in the long bones during fracture repair. Blockade of CCN1 by antibodies inhibits bone fracture healing in mice. In the kidney, CCN1 is expressed in podocytes in normal adult and embryonic glomeruli, but expression is decreased in IgA nephropathy, diabetic nephropathy, and membranous nephropathy, particularly in diseased kidneys with severe mesangial expansion. CYR61 induction of cellular senescence in the kidney is a potential therapy to limit fibrosis.
== History == Alimentiv operated as Robarts Clinical Trials, part of Western University starting in 1986. In 2020 the company was purchased from Western University and began operations as Alimentiv Inc., the rebranding supposedly reflected the company’s continued growth as a specialized contract research organization. Today, Alimentiv provides services in more than 64 countries worldwide, collaborates with leading scientists and organizations around the globe such as Summit Clinical Research, LLC, and works with pharmaceutical and biotechnology organizations to bring new and improved GI treatment options to patients. In 2021, Alimentiv acquired McDougall Scientific Ltd., a niche CRO specializing in statistical analysis, data management, reporting, and clinical trial design. This was followed by Alimentiv launching AcelaBio in 2021, a commercial research laboratory, located in San Diego, CA delivering histopathology and precision medicine services for global clinical trials.
Sources: en.wikipedia.org
=== Electrochemical skin conductance === Electrochemical skin conductance (ESC) is an objective, quantitative, non-invasive method for the assessment of sudomotor function that utilizes chronoamperometry (the application of rectangular direct current (DC) pulses of varying voltage amplitudes) to electrically stimulate eccrine sweat glands, and reverse iontophoresis (the migration of electrolytes from the human sweat to the electrodes) for quantitative measurement of the resulting flow of Cl- ions. ESC can be measured with the use of a medical device called Sudoscan. A novel electrochemical model of the skin was devised, reproducing the behavior of chloride ions and the properties of their ion channel to develop a computational tool for measuring chloride ion flow through a sweat gland in response to an imposed voltage. In vitro electrochemical studies were then carried out in conventional three-electrode cells to identify the origin of currents measured upon the application of low voltage potentials with variable amplitudes to stainless steel electrodes applied to the skin during clinical tests. These studies also evaluated the influence of different parameters in sweat (e.g., urea, lactate) on the obtained currents. These studies formed the basis for the ESC methodology of measuring sudomotor function. The flow of Cl− ions in the sweat secreted from the activated sweat glands are captured by the anode. This process is repeated twice for the feet and twice for the hands with the right and left electrodes alternating as the anode and cathode.
In the United States, an all-out effort for making atomic weapons was begun in late 1942. This work was taken over by the U.S. Army Corps of Engineers in 1943, and known as the Manhattan Engineer District. The top-secret Manhattan Project, as it was colloquially known, was led by General Leslie R. Groves. Among the project's dozens of sites were: Hanford Site in Washington, which had the first industrial-scale nuclear reactors and produced plutonium; Oak Ridge, Tennessee, which was primarily concerned with uranium enrichment; and Los Alamos, in New Mexico, which was the scientific hub for research on bomb development and design. Other sites, notably the Berkeley Radiation Laboratory and the Metallurgical Laboratory at the University of Chicago, played important contributing roles. Overall scientific direction of the project was managed by the physicist J. Robert Oppenheimer. In July 1945, the first atomic explosive device, dubbed "The Gadget", was detonated in the New Mexico desert in the Trinity test. It was fueled by plutonium created at Hanford. In August 1945, two more atomic devices – "Little Boy", a uranium-235 bomb, and "Fat Man", a plutonium bomb – were used against the Japanese cities of Hiroshima and Nagasaki.
K—Lysine D—Aspartic acid E—Glutamic acid L—Leucine Therefore, the KDEL sequence in three letter code is: Lys-Asp-Glu-Leu. The soluble resident protein will remain in the ER as long as it contains a KDEL signal sequence on the C-terminal end of the protein. However, since vesicle budding is such a dynamic process, and there is a high concentration of soluble proteins in the ER, soluble proteins are inadvertently transported to the cis-golgi via COPII coated vesicles. The transportation mechanism of proteins containing the KDEL signal sequence is facilitated by KDEL receptors attached to COPII and COPI vesicles.
=== Growth plate === PTHrP is found in the proliferative zone of the growth plate. It is one of the main proteins that regulates mesenchymal stem cell activity. Current research suggests that PTHrP promotes the proliferation of early-phase chondrocytes and inhibits their differentiation into hypertrophic chondrocytes. It is involved in a negative feedback loop with Indian Hedgehog (Ihh).
Committee on Natural Resources Subcommittee on Federal Lands Subcommittee on Water, Wildlife and Fisheries Committee on Oversight and Government Reform Subcommittee on Delivering on Government Efficiency (Ranking Member)
Sources: en.wikipedia.org
LC-MS/MS is common, often after sample cleanup. The assay targets GW501516 or its metabolites.
Reference material is usually kept cold, dry, and protected from light. Frozen aliquots reduce repeated freeze-thaw cycles.
No approved pharmaceutical product exists, so manufacturing and quality controls are not standardized. Products may contain different compounds or impurities.
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.