The short version of anti-doping fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-07-15. Anything still debated is marked as such rather than presented as settled.
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.
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.
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 |
|---|---|---|
| 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 |
Clinical development stopped after rodent studies showed tumors at multiple sites. Whether those findings predict human cancer risk remains an open question, but they led sponsors to discontinue programs. Human safety data are limited to small, short-term studies that were not designed to assess cancer risk. Reported effects in those studies included changes in blood lipids, but the evidence is insufficient for medical use. Long-term consequences of nonmedical use are not well characterized. Questions about dose, duration, and individual susceptibility remain unresolved.
Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.
Regulatory treatment varies, but cardarine is not approved as a medicine. Sports authorities list GW501516 as a prohibited substance, and it is banned at all times under the World Anti-Doping Agency code. Many countries restrict sales for human consumption, while online vendors market it as a research chemical. Such products may lack purity data, and their actual contents can differ from the label. Purchasing or possessing cardarine may carry legal consequences depending on jurisdiction. The compound is not a dietary supplement ingredient in regulated markets.
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.
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.
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.
Laboratory detection of cardarine typically involves sample preparation followed by chromatographic separation and mass spectrometric identification. Urine is the most common matrix for anti-doping tests, though blood and hair have also been explored. Methods can target the parent compound or its metabolites, depending on the expected window of detection. Reference standards are required for accurate quantification. Matrix effects and dilution can influence results, so laboratories use internal standards and validation protocols. The exact detection window varies with dose, route, and individual metabolism.
Anti-doping laboratories detect GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be used in some programs. Detection depends on factors such as dose, timing, metabolism, and the sensitivity of the assay. Published methods describe limits of detection in the low nanogram per milliliter range for related compounds. Exact detection windows are not fixed for all situations and remain an area of ongoing study.
Products sold as cardarine have been found to contain incorrect compounds, variable amounts, or no active ingredient at all. Independent testing is required to verify identity and purity. Common analytical approaches include high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance for structural confirmation. These methods can distinguish GW501516 from related PPAR agonists and from unrelated steroids. For regulators and researchers, such verification is central to interpreting both biological results and adverse event reports.
Cardarine is prohibited in competitive sport under the World Anti-Doping Agency code, where it is classified as a metabolic modulator. It is not approved as a prescription medicine in the United States, European Union, or other major markets. Regulatory action has focused on its presence in sports and in products marketed as research chemicals. Because it has no accepted medical indication, supply is often unregulated. This status creates legal and safety uncertainties for anyone who encounters the substance.
The fictional timeline of the MCU includes the feature films, television series, television specials, short films, and the I Am Groot shorts from Marvel Studios and Marvel Television's Netflix series. While the early films of Phase One and Phase Two of the franchise followed each other in the timeline similar to their release order, Phase Three saw many of the films overlapping with each other in the timeline, while also introducing the first prequel property, Captain Marvel. The Phase Three film Avengers: Endgame featured characters traveling into the past and introduced a five-year time jump, with many subsequent releases in Phase Four and Phase Five set after Endgame's events in the timeline. The television series Loki and What If...? were the first properties to occur outside of the main timeline and explore alternative timelines and universes. There have been numerous attempts by Marvel Studios and others to codify the events of the MCU, which have been subject to perceived continuity errors, resulting in Marvel Studios releasing an official timeline book in 2023 for their first four phases that were designated as part of their "Sacred Timeline". This book did not feature projects produced by other companies, such as Marvel Television's series, which were all loosely connected to the films; however, it was noted that all of these outside projects were part of the larger Marvel canon. In early 2024, Marvel Studios formally integrated Marvel Television's group of Netflix series into its Disney+ timeline.
Aluminon, the triammonium salt of aurintricarboxylic acid, is a dye often used to detect the presence of the aluminium ion in an aqueous solution. Aluminon forms a red complex salt in combination with Al3+. In addition to its use in qualitative inorganic analysis, aluminon has applications in pigment production. It forms brilliantly colored lake pigments with many metals. The pigments are red in combination with Be2+ and Ga3+. The pigment is deep purple or reddish-brown in combination with Fe3+. Color of a particular pigment in acidic solutions may change: aluminon and Sc3+ form red pigments if the solution is acidic, but otherwise the solutions are colorless. Aluminon is prepared by reacting sodium nitrite with salicylic acid, adding formaldehyde, then treating with ammonia. Analytical chemistry Colorimetry
The H-type pseudoknot core of mini-NAD⁺-II aptamers is structurally analogous to that of the preQ1-I riboswitch class, one of the smallest known natural riboswitch aptamers. Both classes represent the shortest known natural RNA aptamers, yet achieve high ligand-binding specificity. This structural similarity suggests that simple H-type pseudoknots may function as versatile scaffolds for constructing ligand-binding aptamers, either naturally or synthetically. Biochemical analysis using in-line probing confirmed that mini-NAD⁺-II RNAs bind both NAD⁺ and NMN, with strong preference for NMN. Biochemical analysis using in-line probing confirmed that mini-NAD⁺-II RNAs bind both NAD⁺ and NMN, with strong preference for NMN. Mini-NAD⁺-II aptamers discriminate more strongly between NMN and NAD⁺ than the larger P1a containing aptamers, likely because they lack the conserved adenosines flanking P1a that make non-specific contacts with the adenosine moiety of NAD⁺. Gene Regulation NAD⁺-II and mini-NAD⁺-II riboswitches are predicted to function as translational "OFF" switches: when NAD⁺ or NMN concentrations are sufficiently high, the riboswitch ligand-bound conformation sequesters the Shine-Dalgarno sequence within a pseudoknot, preventing ribosome binding and repressing translation of the downstream gene. The downstream genes regulated by NAD⁺-II and mini-NAD⁺-II riboswitches include:
The image above shows the interpretation of an antibody panel used in serology to detect antibodies towards the most relevant blood group antigens. Each row represents "reference" or "control" red blood cells of donors which have known antigen compositions and are ABO group O. The + symbol means that the antigen is present on the reference red blood cells, and 0 means it is absent; nt means "not tested". The "result" column to the right displays reactivity when mixing reference red blood cells with plasma from the patient in 3 different phases: room temperature, 37 °C and AHG (with anti-human globulin, by the indirect antiglobulin test).
An article in the Hindustan Times stated: "A male star who started the trend of taking his shirt off in films and a younger star who flaunted his rippling muscles in a double role in a recent hit film also rely heavily on steroids. Model-actor and former Mr India Aryan Vaid says, "I know of 'trainers' of mega stars who don't know a thing about fitness. Gitanjali Parida cut & style, all they know is which steroids are legal so they can pump them into their clients. Most of the knowledge they have is off the Internet. But, they do good business because they have big names as their clients, some of whom pay these trainers as much as Rs 1 lakh a month for getting them perfect bodies. I've seen actors and models take injections to bulk up even before photo shoots... they don't realise what it's doing to their body.". In the same article, Satya Chaurasia, the fitness trainer whose clients include Aamir Khan and Hrithik Roshan, and he clarified that none of his clients have ever used steroids. "It's a common practice in Bollywood to take anabolic steroids to bulk up fast for photo sessions or shoots. I don't recommend them because I know the consequences."
Sources: en.wikipedia.org
34. Adv Gerontol. 2006;19:72-8. [Effect of age, different light conditions, melatonin, and epitalon on lysosomal proteinase activity in the liver and kidneys of rats]. [Article in Russian] Rendakov NL, Tiutiunnik NN, Vinogradova IA. Ageing, melatonin, epithalon (tetrapeptide Ala-Glu-Asp-Gly) and different light conditions effects on protein content and cathepsins B and D activities in rat liver and kidneys lysosomal fractions were studied. Ageing leads to decrease of cathepsins activity in rat liver lysosomal fractions. Constant light and darkness conditions result in earlier age decline of cathepsins activity. Absence of day and night succession in comparison with alternating light conditions causes decline of both general and specific cathepsin D activity. Melatonin and epithalon administration resulted in decrease of cathepsin D activity in liver only under control interchangeable light conditions. Cathepsin B activity in liver and kidneys lysosomal fractions declined in all experimental light conditions. Cathepsins activity decrease under the influence of epiphysial factors is evidently connected with their inhibitory effect on protein and general metabolism.
Transcription of mRNA: Synthesis begins with turning on genes associated with the formation of a particular alpha peptide (typically alpha 1, 2 or 3). About 45 genes are associated with collagen formation, each coding for a specific mRNA sequence, and are typically named with the "COL" prefix. These 45 genes encode the 28 collagen types described in vertebrates. Pre-pro-peptide formation: The created mRNA exits the cell nucleus into the cytoplasm. There, it links with the ribosomal subunits and is translated into a peptide. The peptide goes into the endoplasmic reticulum for post-translational processing. It is directed there by a signal recognition particle on the endoplasmic reticulum, which recognizes the peptide's N-terminal signal sequence (the early part of the sequence). The processed product is a pre-pro-peptide called preprocollagen. Pro-collagen formation: Three modifications of the pre-pro-peptide form the alpha peptide: The signal peptide on the N-terminal is removed. This molecule is called 'propeptide.' Lysines and prolines are hydroxylated by the enzymes 'prolyl hydroxylase' and 'lysyl hydroxylase', producing hydroxyproline and hydroxylysine. This helps in cross-linking the alpha peptides. This enzymatic step requires vitamin C as a cofactor. In scurvy, the lack of hydroxylation of prolines and lysines causes a looser triple helix (which is formed by three alpha peptides). Glycosylation occurs by adding either glucose or galactose monomers onto the hydroxyl groups that were placed onto lysines, but not on prolines.
In 2006, the European Food Safety Authority stated that the SSC opinion was confirmed, that the BSE risk of bone-derived gelatin was small, and that it recommended removal of the 2003 request to exclude the skull, brain, and vertebrae of bovine origin older than 12 months from the material used in gelatin manufacturing.
60–85% collagen 60–80% collagen I 0–10% collagen III 2% collagen IV small amounts of collagens V, VI, and others 15–40% non-collagenous extracellular matrix components, including: 3% cartilage oligomeric matrix protein, 1–2% elastin, 1–5% proteoglycans, 0.2% inorganic components such as copper, manganese, and calcium. Although most of a tendon's collagen is type I collagen, many minor collagens are present that play vital roles in tendon development and function. These include type II collagen in the cartilaginous zones, type III collagen in the reticulin fibres of the vascular walls, type IX collagen, type IV collagen in the basement membranes of the capillaries, type V collagen in the vascular walls, and type X collagen in the mineralized fibrocartilage near the interface with the bone.
== Society and culture == Sinew was widely used throughout pre-industrial eras as a tough, durable fiber. Some specific uses include using sinew as thread for sewing, attaching feathers to arrows (see fletch), lashing tool blades to shafts, etc. It is also recommended in survival guides as a material from which strong cordage can be made for items like traps or living structures. Tendon must be treated in specific ways to function usefully for these purposes. Inuit and other circumpolar people utilized sinew as the only cordage for all domestic purposes due to the lack of other suitable fiber sources in their ecological habitats. The elastic properties of particular sinews were also used in composite recurved bows favoured by the steppe nomads of Eurasia, and Native Americans. The first stone throwing artillery also used the elastic properties of sinew. Sinew makes for an excellent cordage material for three reasons: It is extremely strong, it contains natural glues, and it shrinks as it dries, doing away with the need for knots.
Sources: pubmed.ncbi.nlm.nih.gov
FlF2 and FlCl2 are predicted to be more stable than FlH2. Due to relativistic stabilization of flerovium's 7s27p21/2 valence electron configuration, the 0 oxidation state should also be more stable for flerovium than for lead, as the 7p1/2 electrons begin to also have a mild inert pair effect: this stabilization of the neutral state may bring about some similarities between the behavior of flerovium and the noble gas radon. Due to flerovium's expected relative inertness, diatomic compounds FlH and FlF should have lower energies of dissociation than the corresponding lead compounds PbH and PbF. Flerovium(IV) should be even more electronegative than lead(IV); lead(IV) has electronegativity 2.33 on the Pauling scale, though the lead(II) value is only 1.87. Flerovium could be a noble metal. Flerovium(II) should be more stable than lead(II), and halides FlX+, FlX2, FlX−3, and FlX2−4 (X = Cl, Br, I) are expected to form readily. The fluorides would undergo strong hydrolysis in aqueous solution. All flerovium dihalides are expected to be stable; the difluoride being water-soluble. Spin–orbit effects would destabilize the dihydride (FlH2) by almost 2.6 eV (250 kJ/mol). In aqueous solution, the oxyanion flerovite (FlO2−2) would also form, analogous to plumbite. Flerovium(II) sulfate (FlSO4) and sulfide (FlS) should be very insoluble in water, and flerovium(II) acetate (Fl(C2H3O2)2) and nitrate (Fl(NO3)2) should be quite water-soluble.
== History == In 1991, Merck & Co's simvastatin was approved as an HMG-COA inhibitor to lower the levels of LDL cholesterol. In 2006, Merck & Co's sitagliptin was approved by the FDA for treatment of diabetes mellitus type 2.
The first two bases in the codon create the coding specificity, for they form strong Watson–Crick base pairs and bond strongly to the anticodon of the tRNA. When reading 5' to 3' the first nucleotide in the anticodon (which is on the tRNA and pairs with the last nucleotide of the codon on the mRNA) determines how many nucleotides the tRNA actually distinguishes. If the first nucleotide in the anticodon is a C or an A, pairing is specific and acknowledges original Watson–Crick pairing, that is: only one specific codon can be paired to that tRNA. If the first nucleotide is U or G, the pairing is less specific and in fact two bases can be interchangeably recognized by the tRNA. Inosine displays the true qualities of wobble, in that if that is the first nucleotide in the anticodon, any of three bases in the original codon can be matched with the tRNA. Due to the specificity inherent in the first two nucleotides of the codon, if one amino acid is coded for by multiple anticodons and those anticodons differ in either the second or third position (first or second position in the codon) then a different tRNA is required for that anticodon. The minimum requirement to satisfy all possible codons (61 excluding three stop codons) is 32 tRNAs. That is 31 tRNAs for the amino acids and one initiation codon.
the flow must be steady, that is, the flow parameters (velocity, density, etc.) at any point cannot change with time, the flow must be incompressible—even though pressure varies, the density must remain constant along a streamline; friction by viscous forces must be negligible. For conservative force fields (not limited to the gravitational field), Bernoulli's equation can be generalized as:
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.
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.