1,721,172 research outputs found
Deplezione di glutatione e perossidazione lipidica nell'encefalo di topo in seguito ad intossicazione con bromobenzene
No full textThe use of 3-hydroxy-2-naphthoic acid hydrazide and Fast Blue B for the histochemical detection of lipid peroxidation in animal tissues - A microphotometric study
No full textImaging of oxidative stress at subcellular level by confocal laser scanning microscopy after fluorescent derivativization of cellular carbonyls
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Indirect immunofluorescence detection of protein-bound 4-hydroxynonenal in tissue sections and isolated cells
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Absence of association between a polymorphic GGC repeat in the 5’ untranslated region of the reelin gene and autism
No full textImmunohistochemical detection of protein oxidation
No full textThe oxidative modification of proteins by reactive oxygen species (ROS) and other reactive compounds is associated with a number of disease and pathophysiological processes as well as aging (1). Under physiological conditions, almost all oxidative modifications of proteins are resulting in an increase of carbonylated proteins. The three major pathways leading to carbonyl group formation (protein oxidation) are shown in Fig. 1. Carbonyl groups are introduced into proteins as a result of: 1) metal catalyzed oxidation of amino acid residues; 2) lipid peroxidation (the Michael addition of protein amino, sulfhydryl, and imidazole groups to the double bond of α,β unsaturated aldehydes, which are produced during the oxidation of polyunsaturated fatty acids); and 3) protein glycation and glycoxidation reactions. The carbonyl content of proteins is therefore an index of the amount of oxidative protein damage attributable to either direct attack of free radicals or the modification of proteins by oxidation products of carbohydrates or polyunsaturated fatty acids (PUFAs)
LA MODULAZIONE DEI LIVELLI DI GLUTATIONE COME STRATEGIA DI ATTACCO NELLE INTERAZIONI OSPITE-PARASSITA
Full text linkInsect studies, dealing with parasitism of aphids, have shown that the disruption of host glutathione (GSH) pool and
metabolisms significantly contributes to its physiological regulation and castration. The parasitic wasp Aphidius ervi injects into
host aphids a venom containing large amounts of a gamma-glutamyltransferase (Ae-GGT) enzyme, which causes a depletion of
GSH primarily involving ovarian tissue. Injected Ae-GGT in fact consumes substrate GSH, which ultimately triggers apoptosis.
Studies on virulence factors of microrganisms have documented that the invasion strategies of selected pathogenic bacteria also
target host GSH metabolism. Indeed, it has been shown that GGT activity of Helicobacter pylori and H. suis, the agents responsible
of peptic ulcer, can exert antiproliferative and pro-apoptotic effects in gastric epithelial cells. By confocal microscopy, H. suis outer
membrane vesicles (OMV) − submicroscopic structures 20-50 nm in diameter, budding from the cell surface − were identified as
carriers of H. suis GGT, capable of delivering the enzyme to the deeper mucosal layers. In association with such membranous
structures, active GGT from H. suis in fact translocates across the epithelial layers and can access lymphocytes residing in the
gastric mucosa, resulting in the inhibition of lymphocyte proliferation, i.e., a perturbation of host immunity and a facilitation of
bacterial infection. Cellular GSH appears, thus, to represent a conserved target for parasitic (micro)organisms which aim at altering
host redox homeostasis to weaken its immune defenses, using GGT as a key-element of a virulence strategy. Taking into account
the “parasitic” behavior exhibited by malignant cells spreading across tissues and organs of the patient (the “host”). GGT activity
is in fact expressed in a number of malignant tumors, and expression levels often increase along with progression to more invasive
phenotypes. Now, active GGT can be released from cells, including cancer cells, in association with submicroscopic vesicles resembling
exosomes. The similarity of such structures with GGT-rich OMV particles of H. pylori and H. suis is indeed obvious. GGT
activity of cancer cells can affect intracellular redox equilibrium, and produces in addition significant extracellular effects, e.g. on
the redox status and ligand binding affinity of cell surface receptors related with cell survival/apoptosis balance. Thus, GGT-rich
exosomes shed by cancer cells can produce in host’s surrounding tissues effects comparable to those reported for Ae-GGT or Helicobacter
GGT, possibly resulting in facilitation of malignant cells survival and diffusion
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