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951.
Aldebert D Hypolite M Bal G Dumestre-Pérard C Bertini RL Rolland C Boutonnat J Grillot R Pelloux H Brion JP 《Cellular immunology》2011,270(2):230-236
Phagocytes play a central role in immune defense. Their dysfunction predisposes to infections. This study determined the expression level of nine receptors involved in Aspergillus immune response as well as the values of phagocytosis and production of radical oxygen species after Aspergillus stimulation, in a healthy adult population.The expression values of the CD11b, CD11c, CD14, CD18, CD35, CD181, CD182, CD282 and CD284 receptors on peripheral human monocytes and granulocytes was established. A heterogenous expression of the CD282 on granulocytes was observed as CD181, CD182 and CD284 on monocytes. Similarly, we observed considerable variation in the expression of these receptors over time. Only CD282 on granulocytes varied with sex. No variation with age was observed. Adherence of Aspergillus conidia to phagocytes was dependent of individual, sex, age and time. A better characterization of these innate immunity parameters is necessary to develop in the future an immunologic surveillance strategy for transplant recipients. 相似文献
952.
953.
The present study investigated the role of the glutathione system in seizures induced by diphenyl diselenide (PhSe)2 (50 mg/kg) in rat pups (post natal day, 12–14). Reduced glutathione (GSH) (300 nmol/site; i.c.v.), administered 20 min before (PhSe)2, abolished the appearance of seizures, protected against the inhibition of catalase and δ-aminolevulinic dehydratase (δ-ALA-D) activities and increased glutathione peroxidase (GPx) activity induced by (PhSe)2. Administration of l-buthionine sulfoximine (BSO, a GSH-depleting compound) (3.2 μmol/site; i.c.v.) 24 h before (PhSe)2 increased the percentage (42–100%) of rat pups which had seizure episodes, reduced the onset for the first convulsive episode. In addition, BSO increased thiobarbituric acid reactive species (TBARS) levels and decreased GSH content, catalase, δ-ALA-D and Na+, K+-ATPase activities. Treatment with sub effective doses of GSH (10 nmol/site) and d-2-amino-7-phosphonoheptanoic acid (AP-7, an antagonist of the glutamate site at the NMDA receptor; 5 mg/kg, i.p.) abolished the appearance of seizures induced by (PhSe)2 in rat pups. Sub effective doses of GSH and kynurenic acid (an antagonist of strychnine-insensitive glycine site at the NMDA receptor; 40 mg/kg, i.p.) were also able in abolishing the appearance of seizures induced by (PhSe)2. In conclusion, administration of GSH protected against seizure episodes induced by (PhSe)2 in rat pups by reducing oxidative stress and, at least in part, by acting as an antagonist of glutamate and glycine modulatory sites in the NMDA receptor. 相似文献
954.
In this study, total glutathione content was determined in human spermatozoa before and after cryopreservation. Total GSH in fresh semen was 4.47 ± 0.46 nmol/108 cells. Following semen cryopreservation, GSH decreased to 1.62 ± 0.13 nmol/108 cells, a 64% reduction (p < 0.01). This decrease in GSH content was associated with a decrease in sperm progressive motility (68% of reduction, p < 0.01). Addition of 1 mM GSH to the freezing extender increased the percentage of total motility and sperm viability. It also modified the motility pattern measured by CASA with changes in the straight-line and average path velocities and wobble of the curvilinear trajectory. Addition of GSH to the freezing media reduced spermatozoa ROS levels and increased the level of sulfhydryl groups on membrane proteins. Nevertheless, no effect of GSH addition on lipid membrane disorder or chromatin condensation was detected. Addition of 1 or 5 mM GSH to the thawing media increased the percentage of motile and progressively motile spermatozoa, but no effect on viability was detected. In conclusion, the antioxidant defensive capacity of the GSH is severely altered by the freeze–thawing process. The addition of GSH to the freezing and thawing extender could be of partial and limited benefit in improving the function of frozen human spermatozoa. 相似文献
955.
956.
Shimozu Y Hirano K Shibata T Shibata N Uchida K 《The Journal of biological chemistry》2011,286(33):29313-29324
α,β-Unsaturated aldehydes generated during lipid peroxidation, such as 4-oxoalkenals and 4-hydroxyalkenals, can give rise to protein degeneration in a variety of pathological states. Although the covalent modification of proteins by these end products has been well studied, the reactivity of unstable intermediates possessing a hydroperoxy group, such as 4-hydroperoxy-2-nonenal (HPNE), with protein has received little attention. We have now established a unique protein modification in which the 4-hydroperoxy group of HPNE is involved in the formation of structurally unusual lysine adducts. In addition, we showed that one of the HPNE-specific lysine adducts constitutes the epitope of a monoclonal antibody raised against the HPNE-modified protein. Upon incubation with bovine serum albumin, HPNE preferentially reacted with the lysine residues. By employing N(α)-benzoylglycyl-lysine, we detected two major products containing one HPNE molecule per peptide. Based on the chemical and spectroscopic evidence, the products were identified to be the N(α)-benzoylglycyl derivatives of N(ε)-4-hydroxynonanoic acid-lysine and N(ε)-4-hydroxy-(2Z)-nonenoyllysine, both of which are suggested to be formed through mechanisms in which the initial HPNE-lysine adducts undergo Baeyer-Villiger-like reactions proceeding through an intramolecular oxidation catalyzed by the hydroperoxy group. On the other hand, using an HPNE-modified protein as the immunogen, we raised a monoclonal antibody against the HPNE-modified protein and identified one of the HPNE-specific lysine adducts, N(ε)-4-hydroxynonanoic acid-lysine, as an intrinsic epitope of the monoclonal antibody. Furthermore, we demonstrated that the HPNE-specific epitopes were produced not only in the oxidized low density lipoprotein in vitro but also in the atherosclerotic lesions. These results indicated that HPNE is not just an intermediate but also a reactive molecule that could covalently modify proteins in biological systems. 相似文献
957.
Peroxidases are key player in the detoxification of reactive oxygen species during cellular metabolism and oxidative stress. Membrane-bound isoenzymes have been described for peroxidase superfamilies in plants and animals. Recent studies demonstrated a location of peroxidases of the secretory pathway (class III peroxidases) at the tonoplast and the plasma membrane. Proteomic approaches using highly enriched plasma membrane preparations suggest organisation of these peroxidases in microdomains, a developmentally regulation and an induction of isoenzymes by oxidative stress. Phylogenetic relations, topology, putative structures, and physiological function of membrane-bound class III peroxidases will be discussed. 相似文献
958.
Tannins in plant-herbivore interactions 总被引:2,自引:0,他引:2
Tannins are the most abundant secondary metabolites made by plants, commonly ranging from 5% to 10% dry weight of tree leaves. Tannins can defend leaves against insect herbivores by deterrence and/or toxicity. Contrary to early theories, tannins have no effect on protein digestion in insect herbivores. By contrast, in vertebrate herbivores tannins can decrease protein digestion. Tannins are especially prone to oxidize in insects with high pH guts, forming semiquinone radicals and quinones, as well as other reactive oxygen species. Tannin toxicity in insects is thought to result from the production of high levels of reactive oxygen species. Tannin structure has an important effect on biochemical activity. Ellagitannins oxidize much more readily than do gallotannins, which are more oxidatively active than most condensed tannins. The ability of insects to tolerate ingested tannins comes from a variety of biochemical and physical defenses in their guts, including surfactants, high pH, antioxidants, and a protective peritrophic envelope that lines the midgut. Most work on the ecological roles of tannins has been correlative, e.g., searching for negative associations between tannins and insect performance. A greater emphasis on manipulative experiments that control tannin levels is required to make further progress on the defensive functions of tannins. Recent advances in the use of molecular methods has permitted the production of tannin-overproducing transgenic plants and a better understanding of tannin biosynthetic pathways. Many research areas remain in need of further work, including the effects of different tannin types on different types of insects (e.g., caterpillars, grasshoppers, sap-sucking insects). 相似文献
959.
Dietrich-Muszalska A Olas B Kontek B Rabe-Jabłońska J 《International journal of biological macromolecules》2011,49(1):113-116
Since oxidative stress observed in schizophrenia may be caused partially by the treatment of patients with various antipsychotics, the aim of the study was to establish the effects of beta-d-glucan, polysaccharide derived from the yeast cell walls of species such as Saccharomyces cerevisiae, and the antipsychotics (the first generation antipsychotic (FGA) - haloperidol and the second generation antipsychotic (SGA) - amisulpride) action on plasma lipid peroxidation in vitro. Lipid peroxidation in human plasma was measured by the level of thiobarbituric acid reactive species (TBARS). The samples of plasma from healthy subjects were incubated with haloperidol or amisulpride in the presence of beta-glucan (4 μg/ml). The action of beta-d-glucan was also compared with the properties of a well characterized commercial monomeric polyphenol - resveratrol (3,4′,5-trihydroxystilbene, the final concentration - 4 μg/ml). The two-way analysis variance showed that the differences in TBARS levels were depended on the type of tested drugs (p = 7.9 × 10−6). We observed a statistically increase of the level of biomarker of lipid peroxidation such as TBARS after 1 and 24 h incubation of plasma with haloperidol compared to the control samples (p < 0.01, p < 0.02, respectively). Amisulpride, contrary to haloperidol (after 1 and 24 h) did not cause plasma lipid peroxidation (p > 0.05). We showed that in the presence of beta-glucan, lipid peroxidation in plasma samples treated with haloperidol was significantly decreased. Moreover, we did not observe the synergistic action of beta-glucan and amisulpride on the inhibition of plasma lipid peroxidation. However, the beta-d-glucan was found to be more effective antioxidant, than the solution of pure resveratrol. The presented results indicate that beta-glucan seems to have distinctly protective effects against the impairment of plasma lipid molecules induced by haloperidol. 相似文献
960.
Hannah Gautrey Fergus Nicol Alan A. Sneddon Judith Hall John Hesketh 《Biochimica et Biophysica Acta (BBA)/General Subjects》2011