The short version of PPARδ fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-01-14 and is reviewed periodically as new material appears.
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.
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.
PPARδ is a nuclear receptor that influences transcription of genes involved in fatty acid oxidation, lipid transport, and energy homeostasis. GW501516 binds and activates this receptor with high selectivity relative to PPARα and PPARγ in laboratory assays. Activation alters expression of target genes in skeletal muscle, liver, and adipose tissue in animal models. The exact clinical consequences of these changes in humans remain incompletely characterized, and observed effects in animals do not establish therapeutic benefit or safety.
Published studies have examined GW501516 in animal models of obesity, insulin resistance, and exercise endurance. Early human trials reportedly ended, and development was discontinued after preclinical findings raised concerns about cancer in some rodent studies. Regulatory agencies have not approved cardarine for any medical use. Its availability through non-pharmaceutical channels raises questions about identity, purity, and legal status that are separate from its laboratory pharmacology. Those questions are often addressed through analytical testing rather than assumptions about product labels.
Cardarine is a common name for GW501516, also GW-1516, a synthetic compound developed as a peroxisome proliferator-activated receptor delta (PPARδ) agonist. It belongs to a class of agents that modulate gene transcription related to lipid and energy metabolism. The compound was studied in preclinical and early clinical research for metabolic and cardiovascular conditions, but it did not progress to approved therapeutic use. Its name appears in fitness and sports contexts despite not being approved as a drug.
| Property | Value | Notes |
|---|---|---|
| Primary target | PPARδ (NR1C2) | Nuclear receptor involved in lipid metabolism |
| Preclinical effect | Increased fatty acid oxidation | Observed in rodent studies |
| Key safety signal | Tumors in rodents after long-term exposure | Contributed to halted clinical development |
| Human trial status | No approved product; development stopped | Limited short-term metabolic data |
| Sport regulatory status | Prohibited at all times | WADA hormone and metabolic modulators class |
Cardarine is a common name for GW501516, a synthetic compound studied for its effects on lipid and glucose metabolism. It functions as an agonist at peroxisome proliferator-activated receptor delta, or PPARδ, a nuclear receptor that influences gene expression. The molecule is not a steroid, nor is it a selective androgen receptor modulator. It is also known in research and sports literature as GW-501516 and endurobol. Early laboratory work examined its metabolic activity in cell cultures and animal models.
Activation of PPARδ changes transcription of genes involved in fatty acid transport, mitochondrial function, and skeletal muscle fuel preference. In rodent studies, pharmacological PPARδ activation was associated with increased endurance and altered body composition. These findings generated interest in performance enhancement, but species differences and study designs limit direct extrapolation to humans. Small human trials were conducted in the 2000s and later discontinued. The extent to which cardarine produces similar metabolic or performance effects in people remains an open question.
The compound is typically described as a laboratory compound rather than a therapeutic product. Published reports have explored its role in lipid disorders, insulin sensitivity, and exercise metabolism, yet no major drug regulator has approved it for medical use. Commercial samples sold under the cardarine name may vary in purity and identity. Analytical confirmation is therefore necessary when the material is discussed in scientific or regulatory contexts. Its classification as a prohibited substance in sport further shapes how it is studied and reported.
Published human data are sparse and mostly come from early-phase trials. Those studies examined short-term changes in lipids, glucose, and exercise capacity, but they were not large enough to establish efficacy or long-term safety. Some animal experiments reported increased running endurance, yet such findings do not prove a performance benefit in people. Anti-doping laboratories detect GW501516 and its metabolites in urine or blood using liquid chromatography-tandem mass spectrometry. Detection windows depend on dose, sample type, and individual metabolism. The method is sensitive enough to identify trace residues in tested samples.
Laboratory handling focuses on identity, purity, and stability. Reference standards are typically stored cold and dry, protected from light, because solutions can degrade over time. Analytical checks may use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Impurities and related substances can be separated chromatographically and compared with a known standard. Because cardarine is not an approved drug, compendial monographs are absent, and laboratories often rely on in-house methods. Reported purity varies among unregulated products and should not be assumed from a label.
GW501516 binds and activates PPARδ, a nuclear receptor that influences transcription of genes involved in fatty acid oxidation and energy use. Activation shifts some metabolic pathways in preclinical models, which is why the compound has been studied for lipid disorders and exercise-related endpoints. The exact downstream effects in humans are incompletely mapped. PPARδ is expressed in many tissues, including skeletal muscle, liver, and adipose tissue, so broad activation may have varied consequences. Researchers continue to examine how selective or partial activation might alter the balance between benefits and risks.
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.
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.
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.
The business was founded by Tim Horton, who played in the National Hockey League from 1949 until his death in an auto crash in 1974. The first Tim Horton restaurant was in North Bay, Ontario, and sold hamburgers. The chain's first donut store opened on May 17, 1964, in Hamilton, Ontario, under the name Tim Horton Donuts. The name was later abbreviated to "Tim Horton's" and then changed to "Tim Hortons" without the possessive apostrophe. Soon after Horton opened the store, he met Ron Joyce, a former police constable in Hamilton. In 1965, Joyce took over the fledgling Tim Horton Donut Shop at 65 Ottawa Street North. By 1967, after opening two additional stores, the two became full partners. Upon Horton's death in 1974, Joyce bought out the Horton family's shares for $1 million and took over as sole owner of the existing chain of 40 stores, quickly and aggressively expanding the chain in both geography and product selection. The 500th store opened in 1991. Joyce's aggressive expansion of the business resulted in major changes to the Canadian coffee and donut restaurant market. Many independent donut shops and small chains were driven out of business, while Canada's per-capita ratio of donut shops surpassed that of all other countries. The Horton and Joyce partnership carried on, with the marriage of Joyce's son, Ron Joyce Jr., and Horton's eldest daughter, Jeri-Lynn Horton-Joyce, who were joint owners of Tim Hortons franchises in Cobourg, Ontario, until 2023 when the couple retired after 37 years.
Louisiana governor Jeff Landry requested the deployment of the National Guard for large upcoming events: the Bayou Classic college football event November 27–29, New Year Eve and Day celebrations, and Mardi Gras celebrations in February. The New Orleans police superintendent said, "We are working together and planning their deployment." New Orleans had been the site of the January 1, 2025, terrorism attack in which 14 persons lost their lives and at least 57 persons were injured.
=== Dorsal genital slits in some African tribes === A variety of "dorsal slit" circumcision was once predominant amongst the Maasai tribe of Kenya and Tanzania, and is still practised and found in many of the more remote regions of the very large area known as "Maasailand" generally. However, the Maasai operation is different in this: rather than a dorsal slit from the opening of the prepuce to the corona, a heart shaped "oval" is excised from the dorsum of the prepuce and the glans is pushed through this hole. Later the edges of the cut prepuce will heal. The prepuce is first cut off, leaving only a small part where the main veins are located, which is pulled down and the small hole through which the glans in pushed through is created. The remaining part is left hanging down, but the glans exposed. Formerly tribes that copied the Maasai like the numerous Kikuyu, Embu and Meru of Kenya also practised the same form of circumcision. Photos of the operation and result are numerously found in specialized African books, such as Carol Beckwith and Tepelit Ole Saitoti's Maasai. There are words for the resultant "preputial flap" in the Maa and Gikuyu languages, and possibly in other African tongues. In Gikuyu the word, now archaic, is likely to be ngwati.
=== Solo & local === Since the diffusion of Ca2+ in the cell is spatially restricted, Ca2+ released by a channel does not travel far from its source (the channel mouth) — model estimates are in the 50 nm range. Therefore, the small total amount of Ca2+ released from lysosomal channels will form locally high [Ca2+] domains around the cytosolic face of lysosomal Ca2+ channels. By strategic placement of Ca2+-sensitive decoding proteins within these domains (e.g. in a complex with the channel), local Ca2+ signals can stimulate Ca2+-dependent events — crucially, even in the absence of a global cytosolic Ca2+ signal. This is the modality when lysosomes are acting on their own. The NAADP/TPC axis has been reported to exhibit such signal compartmentation, such local Ca2+ signalling, in different physiological settings. In other words, this local modality can explain why some processes are driven uniquely by NAADP/TPCs rather than other Ca2+ signalling pathways. For example, NAADP/TPCs are unique drivers of cell killing by Cytotoxic T cells. Similarly, phagocytosis via the Fc receptor in the macrophage is driven only by highly local Ca2+ domains generated by NAADP/TPCs (whereas the global ER Ca2+ signals play no role). This unique dependence is not restricted to immune cells, but is also observed in neurons during long-term potentiation, and neuronal differentiation. Angiogenesis is another NAADP/TPC-dependent pathway.
Sources: en.wikipedia.org
2010: Marcia McNutt became the first female director of the United States Geological Survey. 2011: Kazakhstani neuroscience student and computer hacker Alexandra Elbakyan launched Sci-Hub, a website that provides users with pirated copies of scholarly scientific papers. Within five years, Sci-Hub grew to contain 60 million papers and recorded over 42 million annual downloads by users. Elbakyan was finally sued by major academic publishing company Elsevier, and Sci-Hub was subsequently taken down, but it reappeared under different domain names. 2011: Taiwanese-American astrophysicist Chung-Pei Ma led a team of scientists in discovering two of the largest black holes ever observed. 2012: Israeli-American computer scientist and cryptographer Shafi Goldwasser won the Turing award for her contributions to cryptography and complexity theory. 2013: Canadian-British genetic specialist Turi King identified the 500-year-old skeletal remains of King Richard III. 2013: Kenyan ichthyologist Dorothy Wanja Nyingi published the first guide to freshwater fish species of Kenya. 2013: Canadian teenagers Miranda Wang and Jeanny Yao jointly identify a bacteria in British Columbia's Fraser River that breaks down phthalates. 2014: Norwegian psychologist and neuroscientist May-Britt Moser received the Nobel Prize in Physiology or Medicine, shared with Edvard Moser and John O'Keefe, "for their discoveries of cells that constitute a positioning system in the brain".
28 April – 2024 Scottish government crisis: BBC News reports that Yousaf has ruled out an electoral pact between the SNP and Alba Party after Alex Salmond suggested the party would support him in a vote of no confidence in the Scottish Parliament. 29 April – 2024 Scottish government crisis: Yousaf announces his resignation as both leader of the SNP and first minister of Scotland when his successor is chosen. 30 April – Officials at Holyrood confirm that Labour's motion of no confidence in the Scottish Government will be voted on by MSPs the next day.
A bursa is a small fluid-filled sac made of white fibrous tissue and lined with synovial membrane. Bursa may also be formed by a synovial membrane that extends outside of the joint capsule. It provides a cushion between bones and tendons or muscles around a joint; bursa are filled with synovial fluid and are found around almost every major joint of the body.
Sources: en.wikipedia.org
Rodent studies reported increased endurance and fat oxidation after GW501516 exposure. Long-term studies also found higher rates of some tumors, which led to halted development.
Small short-term human trials examined metabolic markers such as lipids and glucose. The trials did not continue after rodent cancer findings, so long-term human safety is unknown.
Controlled human trials have not established a performance benefit. Anecdotal reports exist, but they are not reliable evidence.
Cardarine is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.