دانلود رایگان مقاله لاتین آرژنین دهیدروژناز از سایت الزویر
عنوان فارسی مقاله:
فعالیت آرژنین دهیدروژناز: یک هدف بیولوژیکی جدید ترکیبات جیوه مشخص شده در سلولهای PC12
عنوان انگلیسی مقاله:
Arginine decarboxylase: A novel biological target of mercury compounds identified in PC12 cells
سال انتشار : 2016
برای دانلود رایگان مقاله آرژنین دهیدروژناز اینجا کلیک نمایید.
مقدمه انگلیسی مقاله:
1. Introduction
Mercury and its compounds are a kind of persistent toxic and bioaccumulative pollutant of global concern since their anthropogenic and natural emissions pose high risk to human and environmental health [1,2]. They are classified into three groups: elemental mercury, inorganic mercury such as mercuric chloride (HgCl2), and organic mercury such as methylmercury (MeHg), ethylmercury (EtHg) and phenylmercury (PhHg). The main contribution to human exposure is the ingestion of fish and seafood (MeHg); also, it can occur from vaccines (EtHg), germicide and herbicide (PhHg) and contaminated water and air (HgCl2) [3]. They can accumulate in human organs, including brain, intestine, kidney, liver, and placenta [4]. Mercury compounds have shown a wide range of toxicological effects on human beings, involving especially the central nervous system (CNS) [5], causing damage to the brain, but also to the kidney [6], the cardiovascular [7], and immune systems [8]. The toxic properties of Hg compounds are directly related to the chemical forms of the element. Organic mercury is more efficiently absorbed into the body and subsequently more toxic than inorganic mercury. Elimination in the blood is slow with a half-life (in days) of 45–70 for MeHg, 5.6– 8.8 for EtHg, 19.7–65.6 for inorganic Hg, therefore allowing significant accumulation to occur [9–11]. Many studies show that high level of exposure to mercury induces changes in the CNS, potentially resulting in irritability, fatigue, behavioral changes, tremors, headaches, hearing and cognitive loss, dysarthria, incoordination, hallucinations, and death [12–14]. Among the mercury compounds, MeHg is primarily responsible for the neurological alterations present in humans and experimental animals. MeHg can be transported from the blood to the CNS across the blood–brain barrier as a cysteine complex by the L-type neutral amino acid carrier transport (LAT) system [15–17]. MeHg hampers the physiological increase in glutathione reductase (GR) and glutathione peroxidase (GPx) activities in the rodent CNS during the early postnatal period, but also decreases GPx activity in adult animals [18,19]. Glutamate dyshomeostasis in the CNS represents a critical mechanism in MeHg-induced neurotoxicity [20]. Glutamate is the major excitatory neurotransmitter in the mammalian CNS, where it plays key roles in development, learning, memory and response to injury. However, glutamate at high concentrations at the synaptic cleft acts as a toxin, inducing neuronal injury and death [21]. Increased glutamate concentration seems to depend, at least in part, on increased release and reduced astrocytic glutamate uptake, probably due to the inhibition of Na+ /K+ -ATPase activity by MeHg [22]. On the other hand, glutamate-mediated neurotoxicity has also been dubbed as ‘‘excitotoxicity”, referring to the consequence of the over-activation of the N-methyl-D-aspartate (NMDA)-type glutamate receptor, partially contributes to increased Ca2+ influx into neurons [23]. Increased intracellular Ca2+ levels are associated with the generation of oxidative stress and neurotoxicity [24]. In addition, MeHg-induced disruption of intracellular calcium homeostasis is also independent of NMDA receptor activity in the presence of the NMDA receptor antagonist D-2-amino-5-phosphonovaleric acid (APV) [25]. Although Hg compounds, especially MeHg, have been extensively studied, the molecular mechanisms of Hg species mediated neurotoxicities remain not completely understood. Molecular targets of Hg species involved in neurotoxicities need to be explored.
برای دانلود رایگان مقاله آرژنین دهیدروژناز اینجا کلیک نمایید.
کلمات کلیدی:
Ornithine/lysine/arginine decarboxylase (IPR011193) < InterPro ... www.ebi.ac.uk/interpro/entry/IPR011193 This family is composed of ornithine decarboxylases (ODC), arginine decarboxylases (ADC) and lysine decarboxylases (LDC), and belongs to the pyridoxal ... KEGG ENZYME: 4.1.1.19 www.genome.jp/dbget-bin/www_bget?ec:4.1.1.19 arginine decarboxylase; SpeA; L-arginine carboxy-lyase. Class. Lyases; Carbon-carbon lyases; Carboxy-lyases. BRITE hierarchy. Sysname. L-arginine ... BRENDA - Information on EC 4.1.1.19 - Arginine decarboxylase www.brenda-enzymes.org/enzyme.php?ecno=4.1.1.19 Information on EC 4.1.1.19 - Arginine decarboxylase. speA - Biosynthetic arginine decarboxylase - Escherichia coli (strain ... www.uniprot.org/uniprot/P21170 Catalyzes the biosynthesis of agmatine from arginine. SPE2 - Arginine decarboxylase 2 - Arabidopsis thaliana (Mouse-ear ... www.uniprot.org/uniprot/O23141 arginine decarboxylase activity, polyamine biosynthetic process, putrescine biosynthetic process, response to abscisic acid, response to cold, response to ... Characterization of an Acid-Dependent Arginine Decarboxylase ... jb.asm.org/content/189/20/7376.full by TN Giles - 2007 - Cited by 16 - Related articles The arginine decarboxylase enzyme (ArgDC; EC 4.1.1.19) catalyzes the production of agmatine and CO2 from l-arginine. The two known types of arginine ... Searches related to Arginine decarboxylase arginine decarboxylase test results arginine dihydrolase ornithine decarboxylase test lysine decarboxylase agmatine phosphoglucomutase cadaverine putrescine
