If you have been reading about PPARδ and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-08-20. Numbers and descriptions here follow the published literature rather than marketing material.
Early clinical research explored GW501516 for lipid disorders, obesity, and diabetes. Some short-term human studies reported changes in HDL cholesterol, LDL cholesterol, and triglycerides. The development program was discontinued after rodent studies showed dose-dependent tumor formation in multiple tissues, including liver, bladder, stomach, and skin. These findings raised concerns about long-term cancer risk in humans. Because human exposure data are limited, the clinical significance of the rodent tumors remains uncertain.
Literature on cardarine often separates receptor pharmacology from toxicology. Mechanistic papers describe PPARδ activation and gene expression changes, while safety assessments focus on carcinogenicity and species differences. Questions remain about whether rodent tumors arise through PPARδ-dependent or off-target mechanisms. Another open area is how human metabolism and exposure compare with those in animal studies. Analytical methods such as liquid chromatography–mass spectrometry are used to confirm identity in biological and product samples.
GW501516 acts as an agonist at the peroxisome proliferator-activated receptor delta, a nuclear receptor that regulates gene expression. Activation shifts transcription toward genes involved in fatty acid uptake, oxidation, and energy expenditure. The compound does not bind the androgen receptor and therefore differs from anabolic steroids and SARMs. In rodent models, this metabolic shift has been linked to increased running endurance and reduced fat accumulation. The exact downstream pathways in humans remain incompletely characterized.
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.
| Property | Value | Notes |
|---|---|---|
| Primary target | PPARδ | Nuclear receptor; not androgen receptor |
| Studied indications | Dyslipidemia; obesity; diabetes | Early clinical research; development discontinued |
| Rodent toxicity | Tumor formation in multiple tissues | Dose-dependent findings in some studies |
| Human approval | None | No approved therapeutic use |
| Typical analytical method | LC-MS/MS | Used for identity and quantification |
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.
Detection of GW501516 in biological samples generally relies on liquid chromatography coupled with tandem mass spectrometry. Urine is a common matrix in anti-doping analysis, while blood or plasma may be used in research settings. Sample preparation can involve enzymatic hydrolysis, protein precipitation, or solid-phase extraction before instrumental analysis. Because the compound undergoes metabolism, assays may target the parent molecule, one or more metabolites, or both. Detection windows are not fixed; they depend on factors such as dose, route, individual metabolism, and assay sensitivity. Reference standards are required for accurate identification and quantification.
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.
== Treatment == There is no antidote for strychnine poisoning. Strychnine poisoning demands aggressive management with early control of muscle spasms, intubation for loss of airway control, toxin removal (decontamination), intravenous hydration and potentially active cooling efforts in the context of hyperthermia as well as hemodialysis in kidney failure (strychnine has not been shown to be removed by hemodialysis). Treatment involves oral administration of activated charcoal, which adsorbs strychnine within the digestive tract; unabsorbed strychnine is removed from the stomach by gastric lavage, along with tannic acid or potassium permanganate solutions to oxidize strychnine.
==== Desenrola Brasil ==== In July 2023, the Ministry of Finance launched the first phase of the "Emergency Debt Renegotiation Programme for Indebted Individuals" (popularly known as the Desenrola Brasil programme), a debt renegotiation programme which was divided into two phases. In October of the same year, the second phase, in which non-bank debts were renegotiated, was launched. Desenrola Brasil is made up of four "participants" (the federal government, debtors, creditors (such as financial institutions, public utility services, retail companies, service providers in general, including individual microentrepreneurs and small businesses), and financial agents, such as banks) and has the stated objective of reducing debt among the population (especially the low income and middle classes), as well as facilitating access to credit by the general population.
Post-translational modifications (PTMs) are the covalent processes of changing proteins following their synthesis, and release from ribosomes. PTMs are reversible editing events used and carried out in the overall process of post-translational regulation – the control of the levels of active protein; an irreversible event is proteolysis (protein degradation). PTMs enable the protein's function to be diversified and extended beyond the dictates of transcription. As of 2023 there are more than 650 known types of PTM. PTMs are also prokaryotic processes. PTMs may involve enzymes or occur spontaneously. Proteins are created by ribosomes, which translate mRNA into polypeptide chains, which may then change to form the mature protein product, which is then released from the ribosome. PTMs are important components in cell signalling, as for example when prohormones are converted to hormones. Post-translational modifications can occur on the amino acid side chains or at the protein's C- or N- termini. They can expand the chemical set of the 22 amino acids by changing an existing functional group or adding a new one such as phosphate. Phosphorylation is highly effective for controlling the enzyme activity and is the most common change after translation. Many eukaryotic and prokaryotic proteins also have carbohydrate molecules attached to them in a process called glycosylation, which can promote protein folding and improve stability as well as serving regulatory functions.
In the first half of the 16th century Paracelsus proposed a theory of mineral formation as an analogy to fruit-bearing plants. In 1550 Gerolamo Cardano made an early attempt to explain the shape of crystals as the result of a close packing of spheres. In 1591 Thomas Harriot studied the close packing of cannonballs (spheres). In 1597 Andreas Libavius recognized the geometrical characteristics of crystals and identified salts from their crystal shape.
Gastric acid production is regulated by both the autonomic nervous system and several hormones. The parasympathetic nervous system, via the vagus nerve, and the hormone gastrin stimulate the parietal cell to produce gastric acid, both directly acting on parietal cells and indirectly, through the stimulation of the secretion of the hormone histamine from enterochromaffin-like cells (ECLs). Vasoactive intestinal peptide, cholecystokinin, and secretin all inhibit production. The production of gastric acid in the stomach is tightly regulated by positive regulators and negative feedback mechanisms. Four types of cells are involved in this process: parietal cells, G cells, D cells and enterochromaffin-like cells. Beside this, the endings of the vagus nerve (CN X) and the intramural nervous plexus in the digestive tract influence the secretion significantly. Nerve endings in the stomach secrete two stimulatory neurotransmitters: acetylcholine and gastrin-releasing peptide. Their action is both direct on parietal cells and mediated through the secretion of gastrin from G cells and histamine from enterochromaffin-like cells. Gastrin acts on parietal cells directly and indirectly too, by stimulating the release of histamine. The release of histamine is the most important positive regulation mechanism of the secretion of gastric acid in the stomach. Its release is stimulated by gastrin and acetylcholine and inhibited by somatostatin.
Sources: en.wikipedia.org
=== 1990s === 1994: divests its Waters Chromatography Division to focus on its membrane business 1996: acquires Amicon separation sciences business from W. R. Grace and Company 1997: acquires Tylan General, expanding its gas purification offerings for the microelectronics industry 1999: acquires Bioprocessing Limited, a developer and manufacturer of chromatography
C-type natriuretic peptide (CNP) primarily interacts with NPR-B, which triggers an increase in the concentration of cGMP in the cell. This process can lead to several physiological effects, such as tissue remodeling, reduction of pulmonary hypertension and fibrosis, and stimulation of long bone growth. CNP is highly concentrated in vascular endothelial cells and plays a crucial role in regulating vascular tone through its vasodilatory action. Furthermore, CNP has been shown to have anti proliferative effects on vascular smooth muscle and an inhibitory effect on the migration of human coronary artery smooth muscle cells.
=== Money laundering === Although Mexican drug cartels and their Colombian suppliers generate and launder between $18 billion to $39 billion from sales to the United States each year, the U.S. and Mexican governments have been criticized for their unwillingness or slow response to confront the various cartels' financial operations, including money laundering. The U.S. DEA has identified the need to increase financial investigations relating to the movement of illegal drug funds to Mexico. The DEA has noted that the U.S. and Mexican financial services industry continues to be a facilitator for money laundering. In August 2010, President Felipe Calderón proposed new measures to combat cash smuggling and money laundering. Calderón proposed a ban on cash purchases of real estate and of certain luxury goods that cost more than 100,000 pesos (about US$8,104). His package would also require more businesses to report large transactions, such as real estate, jewelry and purchases of armor plating. In June 2010, Calderón announced strict limits on the amount in U.S. dollars that can be deposited or exchanged in banks, but the restrictions were relaxed in 2014. In 2011, Wachovia, at one time a major U.S. bank, was implicated in laundering money for Mexican drug traffickers. In a settlement, Wachovia paid federal authorities $110 million in forfeiture. A U.S. Senate report from the permanent subcommittee for investigations revealed in July 2012 that HSBC moved $7 billion in bulk cash from Mexico to the U.S., most of it suspected to assist Mexican cartels and U.S.
=== Buffer === As the salt of a weak base (ammonium) and a weak acid (acetic acid), is often used to create a buffer solution. Ammonium acetate is volatile at low pressures. Because of this, it has been used to replace cell buffers that contain non-volatile salts in preparing samples for mass spectrometry. It is also popular as a buffer for mobile phases for HPLC with ELSD and CAD-based detection for this reason. Other volatile salts that have been used for this include ammonium formate. When dissolving ammonium acetate in pure water, the resulting solution typically has a pH of 7, because the equal amounts of acetate and ammonium neutralize each other. However, ammonium acetate is a dual component buffer system, which buffers around pH 4.75 ± 1 (acetate) and pH 9.25 ± 1 (ammonium), but it has no significant buffer capacity at pH 7, contrary to common misconception.
The most common side effect is eye irritation felt as stinging or burning, which occurs in up to a third of patients. Blepharoconjunctivitis occurs in up to 5% of patients. Rarer adverse effects include keratitis, edema and increased lacrimation. Allergies are rare, but seem to be more common than under the related drug timolol. If the substance reaches the nasal mucosa via the tear duct, it can be absorbed into the bloodstream and cause systemic side effects. These include orthostatic hypotension (low blood pressure) and other effects on the heart and circulatory system, breathing problems in people with asthma, and skin symptoms such as itching and aggravation of psoriasis.
Sources: en.wikipedia.org
It targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not act primarily on androgen receptors. This distinction separates it from SARMs.
Rodent studies found dose-dependent tumors in several organs. The sponsor discontinued the program over cancer concerns. Human risk from long-term use remains unknown.
Controlled human endurance trials are lacking. Animal studies show increased exercise capacity under some conditions. Anecdotal reports are not equivalent to clinical evidence.
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.