DPA-714
DPA-714 or ''N'',''N''-diethyl-2-[4-(2-fluoroethoxy)phenyl]-5,7-dimethylpyrazolo[1,5-''a'']pyrimidine-3-acetamide is a selective ligand for the translocator protein (TSPO) currently under evaluation for several clinical applications. For this reason, a practical, multigram synthetic route for its preparation has been described. The binding affinity of DPA-714 for TSPO is reported as ''K''i = 7.0 ± 0.4 nM. [18F]DPA-714 is currently under investigation as a potential radiopharmaceutical for imaging TSPO in living systems using positron emission tomography (PET). DPA-714, along with other members of the DPA class of TSPO ligands, has been shown to decrease microglial activation and increase neuronal survival in a quinolinic acid rat model of excitotoxic neurodegeneration, suggesting potential neuroprotective effects. See also * DPA-713 References {{Translocator protein modulators Pyrazolopyrimidines TSPO ligands Fluoroethyl ethers ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
DPA-713
DPA-713 or ''N'',''N''-diethyl-2-(4-methoxyphenyl)-5,7-dimethylpyrazolo[1,5-''a'']pyrimidine-3-acetamide is a selective ligand for the translocator protein (TSPO). The binding affinity of DPA-713 for TSPO is reported as ''K''i = 4.7 ± 0.2 nM. DPA-713 has been radiolabelled with carbon-11 as a potential radiotracer for imaging the TSPO using positron emission tomography (PET). Radiation dosimetry and biodistribution of [11C]DPA-713 have been assessed in healthy volunteers, indicating that [11C]DPA-713 is a suitable radiotracer for imaging the TSPO in humans. See also * DPA-714 References {{Translocator protein modulators Pyrazolopyrimidines TSPO ligands ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Translocator Protein
Translocator protein (TSPO) is an 18 kDa protein mainly found on the outer mitochondrial membrane. It was first described as peripheral benzodiazepine receptor (PBR), a secondary binding site for diazepam, but subsequent research has found the receptor to be expressed throughout the body and brain. In humans, the translocator protein is encoded by the ''TSPO'' gene. It belongs to a family of tryptophan-rich sensory proteins. Regarding intramitochondrial cholesterol transport, TSPO has been proposed to interact with StAR ( steroidogenic acute regulatory protein) to transport cholesterol into mitochondria, though evidence is mixed. Function In animals, TSPO (PBR) is a mitochondrial protein usually located in the outer mitochondrial membrane and characterised by its ability to bind a variety of benzodiazepine-like drugs, as well as to dicarboxylic tetrapyrrole intermediates of the haem biosynthetic pathway. TSPO has many proposed functions depending on the tissue. The most s ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Binding Affinity
In biochemistry and pharmacology, a ligand is a substance that forms a complex with a biomolecule to serve a biological purpose. The etymology stems from ''ligare'', which means 'to bind'. In protein-ligand binding, the ligand is usually a molecule which produces a signal by binding to a site on a target protein. The binding typically results in a change of conformational isomerism (conformation) of the target protein. In DNA-ligand binding studies, the ligand can be a small molecule, ion, or protein which binds to the DNA double helix. The relationship between ligand and binding partner is a function of charge, hydrophobicity, and molecular structure. Binding occurs by intermolecular forces, such as ionic bonds, hydrogen bonds and Van der Waals forces. The association or docking is actually reversible through dissociation. Measurably irreversible covalent bonding between a ligand and target molecule is atypical in biological systems. In contrast to the definition of lig ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Radiopharmaceutical
Radiopharmaceuticals, or medicinal radiocompounds, are a group of pharmaceutical drugs containing radioactive isotopes. Radiopharmaceuticals can be used as diagnostic and therapeutic agents. Radiopharmaceuticals emit radiation themselves, which is different from contrast media which absorb or alter external electromagnetism or ultrasound. Radiopharmacology is the branch of pharmacology that specializes in these agents. The main group of these compounds are the radiotracers used to diagnose dysfunction in body tissues. While not all medical isotopes are radioactive, radiopharmaceuticals are the oldest and still most common such drugs. Drug nomenclature As with other pharmaceutical drugs, there is standardization of the drug nomenclature for radiopharmaceuticals, although various standards coexist. The International Nonproprietary Names (INNs), United States Pharmacopeia (USP) names, and IUPAC names for these agents are usually similar other than trivial style differences. Th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Positron Emission Tomography
Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. Different tracers are used for various imaging purposes, depending on the target process within the body. For example: * Fluorodeoxyglucose ( 18F">sup>18FDG or FDG) is commonly used to detect cancer; * 18Fodium fluoride">sup>18Fodium fluoride (Na18F) is widely used for detecting bone formation; * Oxygen-15 (15O) is sometimes used to measure blood flow. PET is a common imaging technique, a medical scintillography technique used in nuclear medicine. A radiopharmaceutical – a radioisotope attached to a drug – is injected into the body as a radioactive tracer, tracer. When the radiopharmaceutical undergoes beta plus decay, a positron is emitted, and when the positron interacts with an or ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Microglial Activation
Microglia are a type of neuroglia (glial cell) located throughout the brain and spinal cord. Microglia account for about 7% of cells found within the brain. As the resident macrophage cells, they act as the first and main form of active immune defense in the central nervous system (CNS). Microglia (and other neuroglia including astrocytes) are distributed in large non-overlapping regions throughout the CNS. Microglia are key cells in overall brain maintenance—they are constantly scavenging the CNS for plaques, damaged or unnecessary neurons and synapses, and infectious agents. Since these processes must be efficient to prevent potentially fatal damage, microglia are extremely sensitive to even small pathological changes in the CNS. This sensitivity is achieved in part by the presence of unique potassium channels that respond to even small changes in extracellular potassium. Recent evidence shows that microglia are also key players in the sustainment of normal brain functions und ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Quinolinic Acid
Quinolinic acid (abbreviated QUIN or QA), also known as pyridine-2,3-dicarboxylic acid, is a dicarboxylic acid with a pyridine backbone. It is a colorless solid. It is the biosynthetic precursor to niacin. Quinolinic acid is a downstream product of the kynurenine pathway, which metabolizes the amino acid tryptophan. It acts as an NMDA receptor agonist. Quinolinic acid has a potent neurotoxic effect. Studies have demonstrated that quinolinic acid may be involved in many psychiatric disorders, neurodegenerative processes in the brain, as well as other disorders. Within the brain, quinolinic acid is only produced by activated microglia and macrophages. History In 1949 L. Henderson was one of the earliest to describe quinolinic acid. Lapin followed up this research by demonstrating that quinolinic acid could induce convulsions when injected into mice brain ventricles. However, it was not until 1981 that Stone and Perkins showed that quinolinic acid activates the ''N''-methyl- ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Excitotoxic
In excitotoxicity, nerve cells suffer damage or death when the levels of otherwise necessary and safe neurotransmitters such as glutamate become pathologically high, resulting in excessive stimulation of receptors. For example, when glutamate receptors such as the NMDA receptor or AMPA receptor encounter excessive levels of the excitatory neurotransmitter, glutamate, significant neuronal damage might ensue. Excess glutamate allows high levels of calcium ions (Ca2+) to enter the cell. Ca2+ influx into cells activates a number of enzymes, including phospholipases, endonucleases, and proteases such as calpain. These enzymes go on to damage cell structures such as components of the cytoskeleton, membrane, and DNA. In evolved, complex adaptive systems such as biological life it must be understood that mechanisms are rarely, if ever, simplistically direct. For example, NMDA in subtoxic amounts induces neuronal survival of otherwise toxic levels of glutamate. Excitotoxicity may be invol ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Neurodegeneration
A neurodegenerative disease is caused by the progressive loss of structure or function of neurons, in the process known as neurodegeneration. Such neuronal damage may ultimately involve cell death. Neurodegenerative diseases include amyotrophic lateral sclerosis, multiple sclerosis, Parkinson's disease, Alzheimer's disease, Huntington's disease, multiple system atrophy, and prion diseases. Neurodegeneration can be found in the brain at many different levels of neuronal circuitry, ranging from molecular to systemic. Because there is no known way to reverse the progressive degeneration of neurons, these diseases are considered to be incurable; however research has shown that the two major contributing factors to neurodegeneration are oxidative stress and inflammation. Biomedical research has revealed many similarities between these diseases at the subcellular level, including atypical protein assemblies (like proteinopathy) and induced cell death. These similarities suggest t ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Pyrazolopyrimidines
Pyrazolopyrimidines are a series of isomeric heterocyclic chemical compounds with the molecular formula C6H5N3. They form the central core of a variety of more complex chemical compounds including some pharmaceuticals and pesticides. Pharmaceuticals One isomer of pyrazolopyrimidines, known as pyrazolo[1,5-''a'']pyrimidine, is the basis for a class of sedative and anxiolytic medication, drugs related (in terms of their effect) to benzodiazepines. Most of the drugs from this class marketed to date are intended to induce sleep, and are prescribed for people suffering insomnia, however some newer compounds produce anxiolytic effects with relatively little sedation, and are being developed for use as non-sedating anti-anxiety drugs. They include: * Zaleplon - hypnotic (trade name Sonata) * Indiplon - hypnotic * Ocinaplon - anxiolytic * Lorediplon - hypnotic As they are not chemically related to the benzodiazepines despite their similar effect, such drugs—as well as the imidazopy ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
TSPO Ligands
TSPO can refer to: * Tokyo Ska Paradise Orchestra * Translocator protein Translocator protein (TSPO) is an 18 kDa protein mainly found on the outer mitochondrial membrane. It was first described as peripheral benzodiazepine receptor (PBR), a secondary binding site for diazepam, but subsequent research has found the re ... {{disambig ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |