A practical reference on Nuclear receptor: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-05-08 and is reviewed periodically as new material appears.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic PPARδ agonist | Not a steroid or a selective androgen receptor modulator. |
| Common synonyms | Cardarine, GW501516, GW-501516, endurobol | Names vary by supplier and literature source. |
| Appearance | White to off-white powder | Consistent with many small-molecule research chemicals. |
| Solubility | Low in water; soluble in DMSO and ethanol | Often prepared in organic solvent for laboratory work. |
| Primary target | PPARδ (NR1C2) | Nuclear receptor involved in lipid and energy metabolism. |
Cardarine can be detected in biological samples and product materials using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method separates compounds by chromatography and identifies them by mass-to-charge transitions, allowing low-level detection in urine or blood. Sample preparation often involves enzymatic hydrolysis, solid-phase extraction, or protein precipitation. Certified reference materials and isotope-labeled internal standards improve quantification. Detection windows depend on metabolism, matrix, and assay sensitivity, so no single universal window applies.
Regulatory treatment of cardarine differs by context and jurisdiction. In competitive sport, the World Anti-Doping Agency lists PPARδ agonists, including GW501516, as prohibited at all times. Outside sport, it lacks approval as a prescription medicine in major drug markets, and products sold for human consumption may be treated as unapproved drugs. Some countries also restrict importation or sale through general consumer protection and medicines laws. These classifications affect availability, testing, and legal risk without establishing therapeutic value.
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.
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.
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.
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.
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.
=== Cerebral edema === Cerebral edema, if associated with coma, often necessitates admission to intensive care, artificial ventilation, and close observation. The administration of fluids is slowed. The ideal treatment of cerebral edema in DKA is not established, but intravenous mannitol and hypertonic saline (3%) are used—as in some other forms of cerebral edema—in an attempt to reduce the swelling. Cerebral edema is unusual in adults.
Hormonal IUDs (referred to as intrauterine systems in the UK) work by releasing a small amount of levonorgestrel, a progestin. The progestin released by hormonal IUDs primarily acts locally within the uterus, resulting in much lower systemic progestin levels than other progestogen only contraceptives. Each type of hormonal IUD varies in size, amount of levonorgestrel released, and duration of effectiveness. The predominant mechanism of action of progestin in the uterus is thickening the cervical mucus to prevent sperm from reaching the fallopian tubes and ultimately the egg. Hormonal IUDs can also thin the endometrial (uterine) lining and potentially impair implantation, but this is not their usual function. Because they thin the endometrial lining, hormonal IUDs often reduce or entirely stop menstrual bleeding. As a result, they are often used to treat menorrhagia (heavy menses), once pathologic causes of menorrhagia (such as uterine polyps) have been ruled out.
=== Natural language processing === In natural language processing, a one-hot vector is a 1 × N matrix (vector) used to distinguish each word in a vocabulary from every other word in the vocabulary. The vector consists of 0s in all cells with the exception of a single 1 in a cell used uniquely to identify the word. One-hot encoding ensures that machine learning does not assume that higher numbers are more important. For example, the value '8' is bigger than the value '1', but that does not make '8' more important than '1'. The same is true for words: the value 'laughter' is not more important than 'laugh'.
=== East Asia === Some historians believe that saffron came to China with Mongol invaders from Persia. In the field of traditional Chinese medicine, it was first mentioned in the Yinshan zhengyao as an ingredient to treat "internal blazing of heart fire". Shennong Bencaojing, a pharmacopoeia written around 300–200 BC and traditionally credited to the legendary Yan Emperor and the deity Shennong, also mentions saffron among 252 plant-based medical treatments for various disorders. Nevertheless, around the 3rd century AD, the Chinese were referring to it as having a Kashmiri provenance through the Silk Road. According to the herbalist Wan Zhen, "the habitat of saffron is in Kashmir, where people grow it principally to offer it to the Buddha". Wan also reflected on how it was used in his time: "The flower withers after a few days, and then the saffron is obtained. It is valued for its uniform yellow colour. It can be used to aromatise wine." Saffron is a less common food colouring ingredient in local Chinese cuisines than safflower. Since the 1970s, Chinese saffron farming has begun in Maqiao, Shanghai's Minhang district, as well as in Changji, Xinjiang.
Sources: en.wikipedia.org
Despite his advanced age and having stepped down as prime minister, Mahathir remains active on the international stage, frequently travelling, delivering speeches, and continuing to voice his views and influence both domestically and globally. Shortly after Malaysia entered its first movement control order in March 2020, Mahathir underwent self-quarantine at home after having close contact with Bandar Kuching MP Kelvin Yii Lee Wuen, who later tested positive for COVID-19. He formed the Homeland Fighter's Party (PEJUANG) in August 2020. Four other MPs joined the new party, including Mahathir's son Mukhriz. The party was registered in July 2021. In August 2021, Mahathir and other MPs protested in Merdeka Square, calling for Muhyiddin's resignation over the government's response to the COVID-19 pandemic, after being blocked from entering parliament by police. In April 2022, UMNO president Ahmad Zahid Hamidi filed a defamation lawsuit against Mahathir. In June 2022, Mahathir made irrendentist comments by stating that Singapore and the Riau Islands of Indonesia was once owned by Johor, and argued the state should claim them as part of Malaysia. In September 2022, Mahathir said he was open to becoming the prime minister for a third time if there were no other suitable candidates. Having previously said he would not defend his Langkawi parliamentary seat, he announced he would contest the 2022 general election. In the election on 19 November, Mahathir lost his seat and election deposit, marking his first defeat in 53 years.
If it's a legitimate rape, the female body has ways to try to shut the whole thing down." In 2017, Shaw had a supporting role as Gail Hurley in the feature film Stronger, which was directed by David Gordon Green, and starred Jake Gyllenhaal as 2013 Boston Marathon bombing survivor Jeff Bauman. In 2019, it was reported that Shaw is attached to direct an adaption of the Katherine Faw Morris novel Ultraluminous, produced by Steven Soderbergh. In 2020, numerous announcements were made regarding projects Shaw is attached to: she is reported to be writer and executive producer of an HBO series adapting the 1978 Judy Blume novel Wifey, and will direct the first episode; she is reportedly to star in Kill Switch, a film to be directed by Soderbergh; and she is attached to direct an adaption of T Kira Madden's memoir Long Live the Tribe of Fatherless Girls. She is also set to direct a film adaptation of the comic 4 Kids Walk Into a Bank.
Twenty-two radioisotopes of plutonium have been characterized, from 226Pu to 247Pu. The longest-lived are 244Pu, with a half-life of 80.8 million years; 242Pu, with a half-life of 373,300 years; and 239Pu, with a half-life of 24,110 years. All other isotopes have half-lives of less than 7,000 years. This element also has eight metastable states, though all have half-lives less than a second. 244Pu has been found in interstellar space and it has the longest half-life of any non-primordial radioisotope. The main decay modes of isotopes with mass numbers lower than the most stable isotope, 244Pu, are spontaneous fission and alpha emission, mostly forming uranium (92 protons) and neptunium (93 protons) isotopes as decay products (neglecting the wide range of daughter nuclei created by fission processes). The main decay mode for isotopes heavier than 244Pu, along with 241Pu and 243Pu, is beta emission, forming americium isotopes (95 protons). Plutonium-241 is the parent isotope of the neptunium series, decaying to americium-241 via beta emission. Plutonium-238 and 239 are the most widely synthesized isotopes. 239Pu is synthesized via the following reaction using uranium (U) and neutrons (n) via beta decay (β−) with neptunium (Np) as an intermediate:
Sources: en.wikipedia.org
Cardarine is a common name for GW501516, a synthetic PPARδ agonist. It is not a steroid or a selective androgen receptor modulator. It was developed and studied as a research compound for metabolic pathways.
It binds to and activates PPARδ, a nuclear receptor that regulates genes related to fatty acid oxidation and energy use. This activation alters transcription in tissues such as skeletal muscle and liver. The full range of downstream effects in humans is not fully established.
No, cardarine is not known to occur naturally in plants, animals, or humans. It is a synthetic molecule produced for laboratory research. Products labeled as cardarine should therefore be treated as manufactured chemicals with variable purity.
Cardarine targets PPARδ, a nuclear receptor involved in lipid and energy metabolism. It does not bind the androgen receptor in the way SARMs do.