|
Animal Models Of Parkinson's Disease
Animal models of Parkinson's disease are essential in the research field and widely used to study Parkinson's disease. Parkinson's disease is a neurodegenerative disorder, characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). The loss of the dopamine neurons in the brain, results in motor dysfunction, ultimately causing the four cardinal symptoms of PD: tremor, rigidity, postural instability, and bradykinesia. It is the second most prevalent neurodegenerative disease, following Alzheimer's disease. It is estimated that nearly one million people could be living with PD in the United States. There are a variety of models that can be utilized to be able to address important aspects of Parkinson's disease. Researchers can consider disease progression, cell death, behavioral characteristics, and more PD phenotypes. Parkinson's disease animal models are divided into two categories: neurotoxin models and genetic models. Neurotoxin models include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PD Animal Models
PD, P.D., or Pd may refer to: Arts and media * ''People's Democracy'' (newspaper), weekly organ of the Communist Party of India (Marxist) * ''The Plain Dealer'', a Cleveland, Ohio, US newspaper * Post Diaspora, a time frame in the ''Honorverse'' series of science fiction novels * ''Principia Discordia'', a 1965 holy text in Discordianism * Production designer, a profession in film or television * Production diary, a promotional video podcast * Public domain, a copyright status Economics and business * Personnel department, of an organization * Price discrimination, a microeconomic pricing strategy * Probability of default, used in finance (Basel II) * Professional degree, or first professional degree * Professional development, learning to earn or maintain professional credentials * Program director, in service industries * Public Debt, of a government Organizations Companies * Phelps Dodge, a former American mining company, now part of Freeport-McMoRan * Polyphony Digital, dev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nigrostriatal Pathway
The nigrostriatal pathway is a bilateral dopaminergic pathway in the brain that connects the substantia nigra pars compacta (SNc) in the midbrain with the dorsal striatum (i.e., the caudate nucleus and putamen) in the forebrain. It is one of the four major dopamine pathways in the brain, and is critical in the production of movement as part of a system called the basal ganglia motor loop. Dopaminergic neurons of this pathway release dopamine from axon terminals that synapse onto GABAergic medium spiny neurons (MSNs), also known as spiny projection neurons (SPNs), located in the striatum. Degeneration of dopaminergic neurons in the SNc is one of the main pathological features of Parkinson's disease, leading to a marked reduction in dopamine function and the symptomatic motor deficits of Parkinson's disease including hypokinesia, tremors, rigidity, and postural imbalance. Anatomy The connection between the substantia nigra pars compacta and the dorsal striatum is mediated via dopa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotenone
Rotenone is an odorless, colorless, crystalline isoflavone used as a broad-spectrum insecticide, piscicide, and pesticide. It occurs naturally in the seeds and stems of several plants, such as the jicama vine plant, and the roots of several members of Fabaceae. It was the first described member of the family of chemical compounds known as rotenoids. Discovery The earliest record of the now-known rotenone-containing plants used for killing leaf-eating caterpillars was in 1848, and for centuries, the same plants were used to poison fish. The active chemical component was first isolated in 1895 by a French botanist, Emmanuel Geoffroy, who called it ''nicouline'', from a specimen of ''Robinia nicou'', now called ''Lonchocarpus nicou'', while traveling in French Guiana. He wrote about this research in his thesis, published in 1895 after his death from a parasitic disease. In 1902 Kazuo Nagai, Japanese chemical engineer of the Government-General of Taiwan, isolated a pure crystalline ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoamine Oxidase B
Monoamine oxidase B, also known as MAOB, is an enzyme that in humans is encoded by the ''MAOB'' gene. The protein encoded by this gene belongs to the flavin monoamine oxidase family. It is an enzyme located in the outer mitochondrial membrane. It catalyzes the oxidative deamination of biogenic and xenobiotic amines and plays an important role in the catabolism of neuroactive and vasoactive amines in the central nervous system and peripheral tissues (such as dopamine). This protein preferentially degrades benzylamine and phenethylamine. Similarly to monoamine oxidase A (MAOA), it also degrades dopamine hough some new research contradicts this, suggesting that MAOB does ''not'' directly degrade dopamine, but is responsible for GABA synthesis Structure Monoamine oxidase B has a hydrophobic bipartite elongated cavity that (for the "open" conformation) occupies a combined volume close to 700 Å3. hMAO-A has a single cavity that exhibits a rounder shape and is larger in volume t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPP+
MPP+ (1-methyl-4-phenylpyridinium) is a positively charged organic molecule with the chemical formula C12H12N+. It is a neurotoxin that acts by interfering with oxidative phosphorylation in mitochondria by inhibiting complex I, leading to the depletion of ATP and eventual cell death. MPP+ arises in the body as the toxic metabolite of the closely related compound MPTP. MPTP is converted in the brain into MPP+ by the enzyme MAO-B, ultimately causing parkinsonism in primates by killing certain dopamine-producing neurons in the substantia nigra. The ability for MPP+ to induce Parkinson's disease has made it an important compound in Parkinson's research since this property was discovered in 1983. The chloride salt of MPP+ found use in the 1970s as an herbicide under the trade name cyperquat. Though no longer in use as an herbicide, cyperquat's closely related structural analog paraquat still finds widespread usage, raising some safety concerns. History MPP+ has been known since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPTP
MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) is a prodrug to the neurotoxin MPP+, which causes permanent symptoms of Parkinson's disease by destroying dopaminergic neurons in the substantia nigra of the brain. It has been used to study disease models in various animal studies. While MPTP itself has no psychoactive effects, the compound may be accidentally produced during the manufacture of MPPP, a synthetic opioid drug with effects similar to those of morphine and pethidine (meperidine). The Parkinson-inducing effects of MPTP were first discovered following accidental injection as a result of contaminated MPPP. Toxicity Injection of MPTP causes rapid onset of Parkinsonism, hence users of MPPP contaminated with MPTP will develop these symptoms. MPTP itself is not toxic, and as a lipophilic compound can cross the blood–brain barrier. Once inside the brain, MPTP is metabolized into the toxic cation 1-methyl-4-phenylpyridinium (MPP+) by the enzyme monoamine oxidase B (M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPTP Structure
MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) is a prodrug to the neurotoxin MPP+, which causes permanent symptoms of Parkinson's disease by destroying dopaminergic neurons in the substantia nigra of the brain. It has been used to study disease models in various animal studies. While MPTP itself has no psychoactive effects, the compound may be accidentally produced during the manufacture of MPPP, a synthetic opioid drug with effects similar to those of morphine and pethidine (meperidine). The Parkinson-inducing effects of MPTP were first discovered following accidental injection as a result of contaminated MPPP. Toxicity Injection of MPTP causes rapid onset of Parkinsonism, hence users of MPPP contaminated with MPTP will develop these symptoms. MPTP itself is not toxic, and as a lipophilic compound can cross the blood–brain barrier. Once inside the brain, MPTP is metabolized into the toxic cation 1-methyl-4-phenylpyridinium (MPP+) by the enzyme monoamine oxidase B (M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPTP Mechanism
MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) is a prodrug to the neurotoxin MPP+, which causes permanent symptoms of Parkinson's disease by destroying dopaminergic neurons in the substantia nigra of the brain. It has been used to study disease models in various animal studies. While MPTP itself has no psychoactive effects, the compound may be accidentally produced during the manufacture of MPPP, a synthetic opioid drug with effects similar to those of morphine and pethidine (meperidine). The Parkinson-inducing effects of MPTP were first discovered following accidental injection as a result of contaminated MPPP. Toxicity Injection of MPTP causes rapid onset of Parkinsonism, hence users of MPPP contaminated with MPTP will develop these symptoms. MPTP itself is not toxic, and as a lipophilic compound can cross the blood–brain barrier. Once inside the brain, MPTP is metabolized into the toxic cation 1-methyl-4-phenylpyridinium (MPP+) by the enzyme monoamine oxidase B (M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuroinflammation
Neuroinflammation is inflammation of the nervous tissue. It may be initiated in response to a variety of cues, including infection, traumatic brain injury,Ebert SE, Jensen P, Ozenne B, Armand S, Svarer C, Stenbaek DS ''et al.'' Molecular imaging of neuroinflammation in patients after mild traumatic brain injury: a longitudinal 123 I-CLINDE SPECT study. ''Eur J Neurol'' 2019. doi:10.1111/ene.13971. toxic metabolites, or autoimmunity. In the central nervous system (CNS), including the brain and spinal cord, microglia are the resident innate immune cells that are activated in response to these cues. The CNS is typically an immunologically privileged site because peripheral immune cells are generally blocked by the blood–brain barrier (BBB), a specialized structure composed of astrocytes and endothelial cells. However, circulating peripheral immune cells may surpass a compromised BBB and encounter neurons and glial cells expressing major histocompatibility complex molecules, perpetuat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidative Stress
Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily Detoxification, detoxify the reactive intermediates or to repair the resulting damage. Disturbances in the normal redox state of cells can cause toxic effects through the production of peroxides and free radicals that damage all components of the cell, including proteins, lipids, and DNA. Oxidative stress from Cellular respiration, oxidative metabolism causes base damage, as well as DNA damage (naturally occurring), strand breaks in DNA. Base damage is mostly indirect and caused by the reactive oxygen species generated, e.g., O2− (superoxide radical), OH (hydroxyl radical) and H2O2 (hydrogen peroxide). Further, some reactive oxidative species act as cellular messengers in redox signaling. Thus, oxidative stress can cause disruptions in normal mechanisms of cellular signaling. In humans, oxidative stress is thought to be involved in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radical (chemistry)
In chemistry, a radical, also known as a free radical, is an atom, molecule, or ion that has at least one unpaired valence electron. With some exceptions, these unpaired electrons make radicals highly chemically reactive. Many radicals spontaneously dimerize. Most organic radicals have short lifetimes. A notable example of a radical is the hydroxyl radical (HO·), a molecule that has one unpaired electron on the oxygen atom. Two other examples are triplet oxygen and triplet carbene (꞉) which have two unpaired electrons. Radicals may be generated in a number of ways, but typical methods involve redox reactions. Ionizing radiation, heat, electrical discharges, and electrolysis are known to produce radicals. Radicals are intermediates in many chemical reactions, more so than is apparent from the balanced equations. Radicals are important in combustion, atmospheric chemistry, polymerization, plasma chemistry, biochemistry, and many other chemical processes. A majority of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxicity
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell ( cytotoxicity) or an organ such as the liver (hepatotoxicity). By extension, the word may be metaphorically used to describe toxic effects on larger and more complex groups, such as the family unit or society at large. Sometimes the word is more or less synonymous with poisoning in everyday usage. A central concept of toxicology is that the effects of a toxicant are dose-dependent; even water can lead to water intoxication when taken in too high a dose, whereas for even a very toxic substance such as snake venom there is a dose below which there is no detectable toxic effect. Toxicity is species-specific, making cross-species analysis problematic. Newer paradigms and metrics are evolving to bypas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
