Everything below concerns research chemical. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-09-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
GW501516 acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in transcription of genes related to lipid handling and energy use. Activation of PPARδ can shift skeletal muscle toward greater fatty acid oxidation in animal models, which is one reason it drew interest for metabolic disease and exercise research. The exact downstream effects depend on tissue, species, dose, and duration. Human data are sparse, so many proposed benefits remain hypotheses rather than established clinical outcomes.
Laboratory studies have examined GW501516 in cell cultures and rodents for conditions such as dyslipidemia, insulin resistance, and obesity. Some trials in humans were initiated, but development was discontinued after preclinical findings raised concerns about cancer in certain models. Those findings do not prove that the compound causes cancer in people, but they contributed to regulatory caution. Later reviews often describe the evidence as preliminary and insufficient for assessing long-term safety.
In the fitness and bodybuilding literature, cardarine is frequently discussed as an endurance agent or fat-loss compound, although such claims are not supported by robust clinical evidence. Online descriptions often mix animal data, user anecdotes, and marketing language. Researchers who study PPARδ agonists distinguish between receptor activation in controlled experiments and unsupervised use of unverified products. The latter introduces unknown purity, dose, and interactions, making reported experiences difficult to interpret scientifically.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Solubility | Soluble in dimethyl sulfoxide and some organic solvents; practically insoluble in water | Solvent choice affects laboratory handling |
| Typical storage | -20 °C, desiccated, protected from light | Common condition for research samples |
| Analytical method | Liquid chromatography–tandem mass spectrometry (LC-MS/MS) | Used for identification and quantification in biological or product samples |
| Common synonyms | GW501516, GW-501516, GSK-516, Endurobol | Names found in research and anti-doping literature |
| Regulatory status | Unapproved therapeutic; prohibited in competitive sport | Status can vary by country and context |
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.
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.
Anti-doping laboratories identify GW501516 and related metabolites using liquid chromatography coupled with tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be analyzed. The method targets the parent compound and phase I and phase II metabolites, which extend the detection window. Because the substance is prohibited at all times, athletes can be tested outside competition. Detection limits and windows depend on the assay, sample type, and individual metabolism.
At the molecular level, GW501516 binds and activates PPARδ, a nuclear receptor that regulates transcription. Activation shifts expression of genes involved in fatty acid oxidation, energy expenditure, and lipid transport in skeletal muscle and liver. Animal studies report increased endurance and altered lipid profiles after exposure. Human data are limited to small trials and do not establish long-term safety or efficacy. PPARδ also has roles in cell proliferation, so the relationship between activation and cancer risk remains an open question.
Published literature on cardarine includes in vitro assays, rodent experiments, and a small number of human studies. Reports describe effects on exercise capacity and lipid metabolism in animals, while human evidence is sparse. Many online descriptions present the compound as a proven endurance aid, a claim not supported by regulatory approval or large clinical trials. Analytical studies focus on identifying the parent compound and its metabolites in biological samples. Important uncertainties include species differences, dose-response relationships, and the relevance of rodent tumor findings to humans.
In situations where the partial pressure of oxygen in the water is low, diffusion of oxygen into the blood is reduced, Henry's law can explain this phenomenon. The law states that at equilibrium, the partial pressure of oxygen in water will be equal to that in air; but the concentrations will differ due to the differing solubility. This law explains why O. vulgaris has to alter the amount of water cycled through its mantle cavity as the oxygen concentration in water changes. The gills are in direct contact with water – carrying more oxygen than the blood – that has been brought into the mantle cavity of the octopus. Gill capillaries are quite small and abundant, which creates an increased surface area that water can come into contact with, thus resulting in enhanced diffusion of oxygen into the blood. Some evidence indicates that lamellae and vessels within the lamellae on the gills contract to aid in propelling blood through the capillaries.
==== Gene expression ==== According to several published articles, H-DNA has the ability to regulate gene expression depending on factors such as location and sequences in proximity. Although intergenic regions of the prokaryotic genome have shown low traces of naturally occurring H-DNA or triplex motifs, H-DNA structures have shown to be more prevalent in the eukaryotic genome. H-DNA has been shown to be especially abundant in mammalian cells including humans (1 in every 50,000 bp). Genetic sequences involved in gene regulation are typically found in the promoter regions of the eukaryotic genome. Consequently, the promoter region has displayed the ability to form H-DNA with a higher frequency. A bioinformatic analysis of the S. cerevisiae genome observed the occurrence of H-DNA and other triplate DNA motifs in four organizational regions: introns, exons, promoter regions and miscellaneous regions. The bioinformatic displayed a total of 148 H-DNA or triplet DNA possible structures. The promoter region accounted for the higher frequency with 71 triplate structures, while the exons accounted for 57 triplate structures and the introns and miscellaneous accounted for 2 and 18 structures. In vitro and in vivo studies of eukaryotic genome expression resulted in one of three results: up regulation, down regulation, or no change in the presence of H-DNA motifs. Kato et al. reported upregulation expression of lacZ, when H-DNA was introduced to the B-lactamase promoter.
=== Caffeine === Caffeine is the most widely consumed stimulant in North America. Caffeine causes the release of epinephrine from the adrenal medulla. In small doses, caffeine can improve endurance. It has also been shown to delay the onset of fatigue in exercise. The most probable mechanism for the delay of fatigue is through the obstruction of adenosine receptors in the central nervous system. Adenosine is a neurotransmitter that decreases arousal and increases sleepiness. By preventing adenosine from acting, caffeine removes a factor that promotes rest, and delays fatigue.
Sources: en.wikipedia.org
Gender inequalities in France affect several areas, including family life, education, employment, health, and political participation. The United Nations Development Programme (UNDP) monitors gender disparities through the Gender Inequality Index (GII), which evaluates reproductive health, empowerment, and labor market participation.
The percentage for terrible governance fell from 35% to 32%, and those who rated governance as regular rose from 22% to 25%. Between 10 and 14 August, the Genial/Quaest institute carried out its fourth survey on Lula's and his government's performance, interviewing 2,029 voters, and the results were that 42% rated the Lula government positively, while 29% classified it as regular and 24% as negative. Those who did not know or did not respond accounted for 5%. Another Ipec survey was conducted between 1 and 5 September with 2,000 voters responding in 127 municipalities, all aged over 16. Respondents who said the government was excellent or good accounted for 40% (3% higher compared with June of that year). For those who still considered it a regular government, the figure remained 32%, and those who said the government was terrible or bad accounted for 25% (3% lower). The same percentage of 3% applied to those who did not know how to rate it. The survey also showed that 56% of Brazilians approve of Lula's way of governing the country, while 39% reject it and 6% did not respond. In a Febraban/Ipespe survey released in September 2023, the popularity of the Lula government increased by 4 percentage points, reaching 55%. Disapproval, meanwhile, fell by two percentage points, to 38%. Also, 59% of Brazilians said the country would improve by the end of the year, as opposed to 18% who were pessimistic.
== Antisense oligonucleotide development == Developments in ASO modification are separated into three generations. Generation one is called backbone-modified and focuses on the phosphodiester group of the nucleotide. This impacts inter-nucleotide binding. These modifications led to better distribution, reduced urinary excretion, and prolonged residence time of the ASOs in the cell. Some examples of first generation modifications include the addition of a phosphorothioate group (PS), methyl group, or nitrogen. The most common is the phosphorothioate group (PS) in which the oxygen atoms of a phosphodiester group are replaced with sulfur atoms, greatly improving efficacy and reducing degradation. Generation two is sugar-modified, focused on the ribose sugar of the nucleotide. This generation saw improved binding affinity while reducing degradation. Some examples of generation two modifications are the substitution of R group with morpholine group (MO) and the usage of phosphorodiamidate morpholino oligomer (PMO) and thiomorpholine oligomer (TMO) as linkages between the ribose sugar and phosphodiester group in the backbone. Generation three is nucleobase-modified, the least common type of modification. These modifications enhanced binding affinity and cell penetration while reducing degradation and off-target effects. Examples include the introduction of G-clamps, pseudoisocytosine, and the substitution of bases with amine, thione, halogen, alkyl, alkenyl, or alkynyl groups.
=== Guest stars === Adam J. Yeend as Danny Mendoza Dearbhla Molloy as Queen Isabel Adam Fergus as Prince Richard Hilty Bowen as Princess Emily Josh Brener as Gavin Price Julie Claire as Francesca Hunter William Russ as Frank Holland Denise Crosby as Janet Holland Brian White as Franklin Russell Jon Tenney as Andrew Nichols
Sources: en.wikipedia.org
=== Cis–trans isomerism and facial–meridional isomerism === Cis–trans isomerism occurs in octahedral and square planar complexes (but not tetrahedral). When two ligands are adjacent they are said to be cis, when opposite each other, trans. When three identical ligands occupy one face of an octahedron, the isomer is said to be facial, or fac. In a fac isomer, any two identical ligands are adjacent or cis to each other. If these three ligands and the metal ion are in one plane, the isomer is said to be meridional, or mer. A mer isomer can be considered as a combination of a trans and a cis, since it contains both trans and cis pairs of identical ligands.
In a complementary technique, peptide mass fingerprinting involves digestion of the native and modified protein with a protease such as trypsin. This will produce a set of peptides that can be analysed using a mass spectrometer. The peptide that changes in mass after reaction with the inhibitor will be the one that contains the site of modification.
== Drug interactions == Smoking is known to increase levels of liver enzymes that break down drugs and toxins. That means that drugs cleared by these enzymes are cleared more quickly in smokers, which may result in the drugs not working. Specifically, levels of CYP1A2 and CYP2A6 are induced: substrates for 1A2 include caffeine and tricyclic antidepressants such as amitriptyline; substrates for 2A6 include the anticonvulsant valproic acid.
Machine learning algorithms train their models to distinguish known disease-associated from neutral mutations whereas other methods do not explicitly train their models but almost all methods exploit the evolutionary conservation assuming that changes at conserved positions tend to be more deleterious. While majority of methods provide a binary classification of effects of mutations into damaging and benign, a new level of annotation is needed to offer an explanation of why and how these mutations damage proteins. Moreover, if the mutation occurs in the region of the gene where transcriptional machinery binds to the protein, the mutation can affect the binding of the transcription factors because the short nucleotide sequences recognized by the transcription factors will be altered. Mutations in this region can affect rate of efficiency of gene transcription, which in turn can alter levels of mRNA and, thus, protein levels in general. Point mutations can have several effects on the behavior and reproduction of a protein depending on where the mutation occurs in the amino acid sequence of the protein. If the mutation occurs in the region of the gene that is responsible for coding for the protein, the amino acid may be altered. This slight change in the sequence of amino acids can cause a change in the function, activation of the protein meaning how it binds with a given enzyme, where the protein will be located within the cell, or the amount of free energy stored within the protein.
The British government took these defeats badly and with the sieges continuing was compelled to send two more divisions plus large numbers of colonial volunteers. By January 1900 this would become the largest force Britain had ever sent overseas, amounting to 180,000 men with further reinforcements being sought. While watching for these reinforcements, Buller made another bid to relieve Ladysmith by crossing the Tugela west of Colenso. Buller's subordinate, Major General Charles Warren, successfully crossed the river, but was faced with a fresh defensive position centred on a prominent hill known as Spion Kop. In the resulting Battle of Spion Kop, British troops captured the summit by surprise during the early hours of 24 January 1900, but as the fog lifted, they realised too late that they were overlooked by Boer gun emplacements on the surrounding hills. The rest of the day resulted in a disaster caused by poor communication between Buller and his commanders. Between them they issued contradictory orders, on the one hand ordering men off the hill, while other officers ordered fresh reinforcements to defend it. The result was 350 men killed and nearly 1,000 wounded and a retreat across the Tugela River into British territory. There were nearly 300 Boer casualties. Buller attacked Louis Botha again on 5 February at Vaal Krantz and was again defeated. Buller withdrew early when it appeared that the British would be isolated in an exposed bridgehead across the Tugela, for which he was nicknamed "Sir Reverse" by some of his officers.
Sources: en.wikipedia.org
It binds and activates PPARδ, a nuclear receptor that influences gene expression related to fatty acid metabolism and energy balance. This mechanism has been studied mainly in animals and cell models, not established as a safe human therapy.
No. It is not an anabolic-androgenic steroid; it is a synthetic PPARδ agonist. Because it is banned in sport, it is sometimes grouped with doping agents even though its chemical class differs from steroids.
Human data are limited and development was discontinued, so major effects and long-term risks are not well characterized. Some early studies examined metabolic markers, but they do not provide a basis for unsupervised use.
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.