Everything below concerns fatty acid oxidation. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-11-05. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| 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 |
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.
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.
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.
United Kingdom In the United Kingdom, transfusion medicine is a sub-speciality of hematology. Serious Hazards of Transfusion (SHOT) collects and analyses reports of adverse events related to transfusion, aiming to improve patient safety. Its reports have led to wider training for medical staff in the UK and a central reporting scheme to allow errors to be reported. There is the Better Blood Continuing Education Programme, which is organised by the EUB which is part of the SNBTS. The EUB consists of many specialist healthcare professionals. The programme's aim is to improve transfusion medicine practise. The programme is reviewed each annually in January. In the UK, there are restrictions in place to decrease the risk of the transmission of Creutzfeldt–Jakob disease.
The enzyme naringenin 8-dimethylallyltransferase uses dimethylallyl diphosphate and (2S)-naringenin to produce diphosphate and 8-prenylnaringenin. Cunninghamella elegans, a fungal model organism of the mammalian metabolism, can be used to study the naringenin sulfation. In plants, the biosynthetic pathway to anthocyanins continues when the enzyme flavanone 3-dioxygenase inserts a hydroxyl group into the dihydropyran ring:
==== Selective androgen receptor modulator-like activity ==== Although bicalutamide has been characterized as a silent antagonist of the AR in prostate tissue and other contexts, and despite its overall antiandrogenic profile, there is evidence that the drug may activate the AR to some degree in certain other tissues, such as muscle and bone among others. This would make bicalutamide a selective androgen receptor modulator (SARM), or a tissue-selective mixed agonist/antagonist or partial agonist of the AR, with antiandrogenic effects in some tissues and androgenic effects in other tissues, rather than a pure antiandrogen. This would be similar to certain other SARMs structurally related to bicalutamide, like enobosarm, which in animals have potent anabolic effects in muscle and bone but show partially agonistic or antagonistic effects in the prostate or seminal vesicles. Bicalutamide has been found to not oppose testosterone-induced increases in levator ani muscle weight in immature castrated male rats at doses of the drug (e.g., 0.08–2 mg/kg) that reduce or even completely block testosterone-induced prostate gland and seminal vesicle growth. In other studies, higher doses of bicalutamide (e.g., 10–30 mg/kg) reduced levator ani muscle weight (by ~40% or more) in gonadally intact male rats but had no effect on lean body mass (a surrogate of muscle mass), whereas castration reduced levator ani weight by around 70% and lean body mass by around 25%.
Sources: en.wikipedia.org
The sharp-nosed pit viper or hundred pacer (Deinagkistrodon acutus) is another Asian species of pitviper that is medically important. This species is considered dangerous, and fatalities are not unusual. According to the U.S. Armed Forces Pest Management Board, the venom is a potent hemotoxin that is strongly hemorrhagic. Bite symptoms include severe local pain and bleeding that may begin almost immediately. This is followed by considerable swelling, blistering, necrosis, and ulceration. Brown (1973) mentions a venom yield of up to 214 mg (dried) and LD50 values of 0.04 mg/kg IV, 4.0 mg/kg IP and 9.2–10.0 mg/kg SC. The envenomation rate is up to 80% and the untreated mortality rate is very low (1–10%). Antivenom is produced in China and Taiwan.
The report of the Royal Commission, published in 1937, recommended the establishment of a Regional Council for Northumberland and Tyneside (to be called the "Northumberland Regional Council") to administer services that needed to be exercised over a wide area, with a second tier of smaller units for other local-government purposes. The second-tier units would form by amalgamating the various existing boroughs and districts. The county boroughs in the area would lose their status. Within this area, a single municipality would be formed covering the four county boroughs of Newcastle, Gateshead, Tynemouth, South Shields and other urban districts and boroughs. A minority report proposed amalgamation of Newcastle, Gateshead, Wallsend, Jarrow, Felling, Gosforth, Hebburn and Newburn into a single "county borough of Newcastle-on-Tyneside". The 1937 proposals never came into operation: local authorities could not agree on a scheme and the legislation of the time did not allow central government to compel one. Tyneside (excluding Sunderland) was a special review area under the Local Government Act 1958. The Local Government Commission for England came back with a recommendation to create a new county of Tyneside based on the review area, divided into four separate boroughs. This was not implemented. The Redcliffe-Maud Report proposed a Tyneside unitary authority, again excluding Sunderland, which would have set up a separate East Durham unitary authority.
Wood fibre, produced from steam friction of wood, is an efficient organic substrate for hydroponics. It has the advantage that it keeps its structure for a very long time. Wood wool (i.e. wood slivers) have been used since the earliest days of the hydroponics research. However, more recent research suggests that wood fibre may have detrimental effects on "plant growth regulators".
ERp57 is an enzyme of the thiol oxidoreductase family located in the ER. It is attached to substrates in an indirect fashion through association with the molecular chaperone calreticulin of the peptide-loading complex, In early stages of generation of MHC-I molecules, ERp57 is associated with free MHC-I heavy chains. As a result, its function is determined by the formation of disulfide bonds in heavy chains, by oxidative folding of the heavy chain, and finally by the fact that ERp57 is loading the peptides onto MHC-I molecules.
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 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.