Astrocyte activation is associated with neuropathology and the production of tissue inhibitor of metalloproteinase-1 (TIMP1). TIMP1 is a pleiotropic extracellular protein that functions both as a protease inhibitor and as a growth factor. Astrocytes that lack expression of do not support rat oligodendrocyte progenitor cell (rOPC) differentiation, and adult global knockout () mice do not efficiently remyelinate following a demyelinating injury.
View Article and Find Full Text PDFEncephalopathies are brain dysfunctions that lead to cognitive, sensory, and motor development impairments. Recently, the identification of several mutations within the -methyl-D-aspartate receptor (NMDAR) have been identified as significant in the etiology of this group of conditions. However, a complete understanding of the underlying molecular mechanism and changes to the receptor due to these mutations has been elusive.
View Article and Find Full Text PDFUnlabelled: Astrocyte activation is associated with neuropathology and the production of tissue inhibitor of metalloproteinase-1 (TIMP1). TIMP1 is a pleiotropic extracellular protein that functions both as a protease inhibitor and as a growth factor. We have previously demonstrated that murine astrocytes that lack expression of do not support rat oligodendrocyte progenitor cell (rOPC) differentiation, and adult global knockout ( ) mice do not efficiently remyelinate following a demyelinating injury.
View Article and Find Full Text PDFAcute bacterial endocarditis is a rapid, difficult to manage, and frequently lethal disease. Potent antibiotics often cannot efficiently kill that colonizes the heart's valves. relies on virulence factors to evade therapeutics and the host's immune response, usurping the host's clotting system by activating circulating prothrombin with staphylocoagulase and von Willebrand factor-binding protein.
View Article and Find Full Text PDFThe mammalian kynurenine aminotransferase (KAT) enzymes are a family of related isoforms that are pyridoxal 5'-phosphate-dependent, responsible for the irreversible transamination of kynurenine to kynurenic acid. Kynurenic acid is implicated in human diseases such as schizophrenia where it is found in elevated levels and consequently KAT-II, as the isoform predominantly responsible for kynurenic acid production in the brain, has been targeted for the development of specific inhibitors. One class of compounds that have also shown inhibitory activity towards the KAT enzymes are estrogens and their sulfate esters.
View Article and Find Full Text PDFIn this study, we report two high-resolution structures of the pyridoxal 5' phosphate (PLP)-dependent enzyme kynurenine aminotransferase-I (KAT-I). One is the native structure with the cofactor in the PLP form bound to Lys247 with the highest resolution yet available for KAT-I at 1.28 Å resolution, and the other with the general PLP-dependent aminotransferase inhibitor, aminooxyacetate (AOAA) covalently bound to the cofactor at 1.
View Article and Find Full Text PDFArterioscler Thromb Vasc Biol
September 2016
Objective: The platelet storage lesion accelerates platelet clearance after transfusion, but the underlying molecular mechanism remains elusive. Although inhibiting sheddase activity hampers clearance of platelets with storage lesion, the target platelet protein responsible for ectodomain shedding-induced clearance is not definitively identified. Monoclonal antibody 5G6 was developed recently to bind specifically human platelet receptor glycoprotein (GP)Ibα and inhibit its shedding but not shedding of other receptors.
View Article and Find Full Text PDFThe HAMLET family of compounds (Human Alpha-lactalbumin Made Lethal to Tumours) was discovered during studies on the properties of human milk, and is a class of protein-lipid complexes having broad spectrum anti-cancer, and some specific anti-bacterial properties. The structure of HAMLET-like compounds consists of an aggregation of partially unfolded protein making up the majority of the compound's mass, with fatty acid molecules bound in the hydrophobic core. This is a novel protein-lipid structure and has only recently been derived by small-angle X-ray scattering analysis.
View Article and Find Full Text PDFThe present study was conducted to determine if the ketogenic diet altered basal levels of monoamine neurotransmitters in mice. The catecholamines dopamine (DA) and norephinephrine (NE) and the indolamine serotonin (5HT) were quantified postmortem in six different brain regions of adult mice fed a ketogenic diet for 3 weeks. The dopamine metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) and the serotonin metabolite 5-hydroxyindole acetic acid (5HIAA) were also measured.
View Article and Find Full Text PDFKynurenine aminotransferase (KAT) isozymes are responsible for catalyzing the conversion of kynurenine (KYN) to kynurenic acid (KYNA), which is considered to play a key role in central nervous system (CNS) disorders, including schizophrenia. The levels of KYNA in the postmortem prefrontal cortex and in the Cerebrospinal fluid (CSF) of schizophrenics are greater than normal brain. A basic strategy to decrease kynurenic acid levels is to promote the inhibition of the biosynthetic KAT isozymes.
View Article and Find Full Text PDFDue to the wide range of chemical structures and variety of mechanisms of action of antischizophrenic agents, it is difficult to identify and confirm a common pharmacophore. The present review summarizes various pharmacophore models for antischizophrenic activity including those based on the new targets, the kynurenine aminotransferase (KATs), which may facilitate the development of novel drugs. Some models illustrate the structural differences of compounds with mechanisms of action considered similar, and yet others demonstrate pharmacophore models for similar chemical classes of compounds for which the mechanism of antischizophrenic action is still not clear.
View Article and Find Full Text PDFInhibitory antibodies to factor VIII (FVIII inhibitors) are the most significant complication in the management of haemophilia A. The immunogenicity of FVIII may be driven in part by structural determinants within the FVIII molecule itself. Regions of nonidentity between human and porcine FVIII possibly could drive differential immune responses.
View Article and Find Full Text PDFJ Undergrad Neurosci Educ
March 2013
Neurochemical analysis of discrete brain structures in experimental animals provides important information on synthesis, release, and metabolism changes following behavioral or pharmacological experimental manipulations. Quantitation of neurotransmitters and their metabolites following unilateral drug injections can be carried out using standard chromatographic equipment typically found in most undergraduate analytical laboratories. This article describes an experiment done in a six session (four hours each) component of a neuroscience research methods course.
View Article and Find Full Text PDFIt has been suggested that excitotoxicity could be contributing to dopamine cell loss after methylphenylpyridinium ion (MPP+) exposure, although the literature regarding this is contradictory. Given that in cell culture excitotoxicity has been reported to be dependent on culture age, we postulated that these discrepant results might be explained by a difference in developmental expression of N-methyl-D-aspartate (NMDA) receptors. To test this, mesencephalic cells were cultured and the number of dopaminergic neurons (tyrosine hydroxylase-immunoreactive cells [TH-IR] cells) expressing the NMDA R1 subunit (NR1) was determined using double-label immunofluorescence microscopy.
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