The short version of PPARδ agonist fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-10-18. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | GW501516, GW-501516, GW 501516, endurobol | Names vary in research and anti-doping documents. |
| Chemical class | Synthetic PPARδ agonist | Small-molecule nuclear receptor ligand. |
| CAS Registry Number | 317318-70-0 | Identifier commonly associated with GW501516. |
| Appearance | White to off-white powder | Typical for purified research material. |
| Solubility | Low in water; soluble in DMSO and ethanol | Organic solvents are common for laboratory stock solutions. |
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.
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.
Safety concerns emerged from long-term animal studies. In rodents given the compound for extended periods, researchers found an increased incidence of certain cancers, including liver and bladder tumors. These findings contributed to the discontinuation of clinical development. Whether similar risks apply to short-term or low-level exposure in humans is not established, and controlled human safety data are limited. The relevance of high-dose rodent carcinogenicity findings to human use remains a subject of debate.
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.
Refrigerator cars required effective insulation to protect their contents from temperature extremes. "Hairfelt" derived from compressed cattle hair, sandwiched into the floor and walls of the car, was inexpensive, yet flawed over its three- to four-year service life, it would decay, rotting out the car's wooden partitions and tainting the cargo with a foul odor. The higher cost of other materials, such as "Linofelt" (woven from flax fibers) or cork, prevented their widespread adoption. Synthetic materials such as fiberglass and polystyrene foam, both introduced after World War II, offered the most cost-effective and practical solution. The United States Office of Defense Transportation implemented mandatory pooling of class RS produce refrigerator cars from 1941 through 1948. World War II experience found the cars spending 60 percent of their time traveling loaded, 30 percent traveling empty, and 10 percent idle; and indicated the average 14 loads each car carried per year included 5 requiring bunker icing, 1 requiring heating, and 8 using ventilation or top icing.
=== Strong magnetic fields === In magnetic fields above 10 tesla, additional plateaus of the Hall conductivity at σxy = νe2/h with ν = 0, ±1, ±4 are observed. A plateau at ν = 3 and the fractional quantum Hall effect at ν = 1/3 were also reported. These observations with ν = 0, ±1, ±3, ±4 indicate that the four-fold degeneracy (two valley and two spin degrees of freedom) of the Landau energy levels is partially or completely lifted.
Mean platelet volume (MPV) is a machine-calculated measurement of the average size of platelets found in blood and is typically included in blood tests as part of the CBC. Since the average platelet size is larger when the body is producing increased numbers of platelets, the MPV test results can be used to make inferences about platelet production in bone marrow or platelet destruction problems. An increased mean platelet volume (MPV) increases the risk to suffer a heart disease MPV may be higher when there is destruction of platelets. This may be seen in immune thrombocytopenic purpura (ITP), myeloproliferative diseases and Bernard–Soulier syndrome. It may also be related to pre-eclampsia and recovery from transient hypoplasia. Abnormally low MPV values may correlate with thrombocytopenia when it is due to impaired production of megakaryocytes in the bone marrow, such as in aplastic anemia. A low MPV may indicate inflammatory bowel disease (IBD), such as Crohn's disease and ulcerative colitis. A high MPV is also a bad prognostic marker in patients with sepsis or septic shock. In addition, low MPV may correlate with abnormally small platelet size, sometimes a symptom of a spectrum referred to as Wiskott–Aldrich syndrome (WAS), caused by a genetic mutation of the WAS gene. Sample for MPV testing is obtained in a Lavender-Top EDTA tube. A typical range of platelet volumes is 7.2 - 11.7 fL (femtolitre), equivalent to spheres 2.65 to 2.9 μm in diameter.
Sources: en.wikipedia.org
Immunohematology is a branch of hematology and transfusion medicine which studies antigen-antibody reactions and analogous phenomena as they relate to the pathogenesis and clinical manifestations of blood disorders. A person employed in this field is referred to as an immunohematologist or colloquially as a blood banker. Their day-to-day duties include blood typing, cross-matching and antibody identification.
Both trials enrolled participants 18 to 75 years old with moderate to severe glabellar lines. Participants received a single intramuscular injection of daxibotulinumtoxinA or placebo at five sites within the muscles between the eyebrows. The most common side effects of daxibotulinumtoxinA are headache, drooping eyelids, and weakness of facial muscles. LetibotulinumtoxinA (Letybo) was approved for medical use in the United States in February 2024. It is indicated to temporarily improve the appearance of moderate-to-severe glabellar lines. The FDA approved letibotulinumtoxinA based on evidence from three clinical trials (BLESS I [NCT02677298], BLESS II [NCT02677805], and BLESS III [NCT03985982]) of 1,271 participants with moderate to severe wrinkles between the eyebrows for efficacy and safety assessment. These trials were conducted at 31 sites in the United States and the European Union. All three trials enrolled participants 18 to 75 years old with moderate to severe glabellar lines (wrinkles between the eyebrows). Participants received a single intramuscular injection of letibotulinumtoxinA or placebo at five sites within the muscles between the eyebrows. The most common side effects of letibotulinumtoxinA are headache, drooping of eyelid and brow, and twitching of eyelid.
Honjōzō (本醸造; 'genuine fermented'): Contains 100% genuine fermented product Kongō-jōzō (混合醸造; 'mixed fermented'): Contains genuine fermented shōyu mash mixed with 30–50% of chemical or enzymatic hydrolysate of plant protein Kongō (混合; 'mixed'): Contains honjōzō or Kongō-jōzō shōyu mixed with 30–50% of chemical or enzymatic hydrolysate of plant protein All the varieties and grades may be sold according to three official levels of quality:
Sources: en.wikipedia.org
Conus geographus, part of the Encyclopædia Romana by James Grout. "Gastridium geographus". Gastropods.com. Retrieved 16 January 2019. Cone Shells - Knights of the Sea Photos of Conus geographus in the Sealife Collection
== Voting == OECD decisions are made through voting, which requires unanimity among all of those voting. Each member country has one vote. However, dissenting members which do not wish to block a decision but merely to signal their disapproval can abstain from voting. 22 of the OECD member countries are also EU member states.
=== Differential diagnoses === The differential diagnoses are extensive and include: Alagille syndrome, alpha-1-antitrypsin deficiency, Byler disease (progressive familial intrahepatic cholestasis), Caroli disease, choledochal cyst, cholestasis, congenital cytomegalovirus disease, congenital herpes simplex virus infection, congenital rubella, congenital syphilis, congenital toxoplasmosis, cystic fibrosis, galactosemia, idiopathic neonatal hepatitis, lipid storage disorders, neonatal hemochromatosis, and total parenteral nutrition-associated cholestasis.
== History == Amino acid activation was first characterized by Mahlon Hoagland, who found that amino acids could be activated by certain enzymes to form an aminoacyl adenylate intermediate compound. The enzymes were discovered to be aminoacyl t-RNA synthetases, responsible for catalyzing the linkage of an amino acid to a small RNA molecule. Hoagland and his collaborator, Paul Zamecnik, later discovered that the small RNA molecule was a tRNA, and they identified it as a key facilitator of translation. Amino acid activation is a key reaction in many biochemical and metabolic processes. In particular, leucine natural killer treatment of interleukin-18 activated cells triggers the mTORC1 metabolic sensor, which indicates that mTORC1 causes amino acid-driven activation due to a high expression in amino acid transporters. The Inhibition of CD98/LAT1 amino acid transporters abroad mTORC1 activation driven by leucine, decreased the activity of the NK cell-effector.
Sources: en.wikipedia.org
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.
No. Cardarine is not a steroid hormone; it targets the nuclear receptor PPARδ. Its classification in anti-doping rules differs from anabolic steroids, though it remains prohibited in sport.
Early rodent studies reported tumor formation at multiple sites, which raised safety concerns. Sponsors stopped clinical development, and no approved human product exists.
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.