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51.
Pereira RP Fachinetto R de Souza Prestes A Puntel RL Santos da Silva GN Heinzmann BM Boschetti TK Athayde ML Bürger ME Morel AF Morsch VM Rocha JB 《Neurochemical research》2009,34(5):973-983
Considering the important role of oxidative stress in the pathogenesis of several neurological diseases, and the growing evidence
of the presence of compounds with antioxidant properties in the plant extracts, the aim of the present study was to investigate
the antioxidant capacity of three plants used in Brazil to treat neurological disorders: Melissa officinalis, Matricaria recutita and Cymbopogon citratus. The antioxidant effect of phenolic compounds commonly found in plant extracts, namely, quercetin, gallic acid, quercitrin
and rutin was also examined for comparative purposes. Cerebral lipid peroxidation (assessed by TBARS) was induced by iron
sulfate (10 μM), sodium nitroprusside (5 μM) or 3-nitropropionic acid (2 mM). Free radical scavenger properties and the chemical
composition of plant extracts were assessed by 1′-1′ Diphenyl-2′ picrylhydrazyl (DPPH) method and by Thin Layer Chromatography
(TLC), respectively. M. officinalis aqueous extract caused the highest decrease in TBARS production induced by all tested pro-oxidants. In the DPPH assay, M. officinalis presented also the best antioxidant effect, but, in this case, the antioxidant potencies were similar for the aqueous, methanolic
and ethanolic extracts. Among the purified compounds, quercetin had the highest antioxidant activity followed by gallic acid,
quercitrin and rutin. In this work, we have demonstrated that the plant extracts could protect against oxidative damage induced
by various pro-oxidant agents that induce lipid peroxidation by different process. Thus, plant extracts could inhibit the
generation of early chemical reactive species that subsequently initiate lipid peroxidation or, alternatively, they could
block a common final pathway in the process of polyunsaturated fatty acids peroxidation. Our study indicates that M. officinalis could be considered an effective agent in the prevention of various neurological diseases associated with oxidative stress. 相似文献
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Cortés-Sarabia Karen Bautista-Santos Isabel Cisneros-Sarabia Alondra Parra-Rojas Isela Estrada-Moreno Ana Karen Flores-Alfaro Eugenia Fernández-Tilapa Gloria Ramírez-Peralta Arturo Vences-Velázquez Amalia 《International journal of peptide research and therapeutics》2021,27(1):413-420
International Journal of Peptide Research and Therapeutics - Gardnerella vaginalis produces vaginolysin (VLY), a cholesterol-dependent cytolysin, responsible of the cellular lysis and epithelial... 相似文献
56.
Juan Del Coso Javier Portillo Gloria Muñoz Javier Abián-Vicén Cristina Gonzalez-Millán Jesús Muñoz-Guerra 《Amino acids》2013,44(6):1511-1519
The aim of this study was to determine the effects of a caffeine-containing energy drink on physical performance during a rugby sevens competition. A second purpose was to investigate the post-competition urinary caffeine concentration derived from the energy drink intake. On two non-consecutive days of a friendly tournament, 16 women from the Spanish National rugby sevens Team (mean age and body mass = 23 ± 2 years and 66 ± 7 kg) ingested 3 mg of caffeine per kg of body mass in the form of an energy drink (Fure®, ProEnergetics) or the same drink without caffeine (placebo). After 60 min for caffeine absorption, participants performed a 15-s maximal jump test, a 6 × 30 m sprint test, and then played three rugby sevens games against another national team. Individual running pace and instantaneous speed during the games were assessed using global positioning satellite (GPS) devices. Urine samples were obtained pre and post-competition. In comparison to the placebo, the ingestion of the energy drink increased muscle power output during the jump series (23.5 ± 10.1 vs. 25.6 ± 11.8 kW, P = 0.05), running pace during the games (87.5 ± 8.3 vs. 95.4 ± 12.7 m/min, P < 0.05), and pace at sprint velocity (4.6 ± 3.3 vs. 6.1 ± 3.4 m/min, P < 0.05). However, the energy drink did not affect maximal running speed during the repeated sprint test (25.0 ± 1.5 vs. 25.0 ± 1.7 km/h). The ingestion of the energy drink resulted in a higher post-competition urine caffeine concentration than the placebo (3.3 ± 0.7 vs. 0.2 ± 0.1 μg/mL; P < 0.05). In summary, 3 mg/kg of caffeine in the form of a commercially available energy drink considerably enhanced physical performance during a women’s rugby sevens competition. 相似文献
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Pseudomonas aeruginosa W51D used citronellol (3,7-dimethyl-6-octen-1-ol) as sole source of carbon and oxidized it to citronellal, citronellic acid and finally to geranic acid. A mutant derived from this strain was isolated as unable to degrade citronellol and had diminished (93%) citronellal dehydrogenase activity. 相似文献
59.
Borroto-Escuela DO Romero-Fernandez W García-Negredo G Correia PA Garriga P Fuxe K Ciruela F 《Cellular physiology and biochemistry》2011,28(5):1009-1022
Acetylcholine challenge produces M(3) muscarinic acetylcholine receptor activation and accessory/scaffold proteins recruitment into a signalsome complex. The dynamics of such a complex is not well understood but a conserved NPxxY motif located within transmembrane 7 and juxtamembrane helix 8 of the receptor was found to modulate G protein activation. Here by means of receptor mutagenesis we unravel the role of the conserved M(3) muscarinic acetylcholine receptor NPxxY motif on ligand binding, signaling and multiprotein complex formation. Interestingly, while a N7.49D receptor mutant showed normal ligand binding properties a N7.49A mutant had reduced antagonist binding and increased affinity for carbachol. Also, besides this last mutant was able to physically couple to Gα(q/11) after carbachol challenge it was neither capable to activate phospholipase C nor phospholipase D. On the other hand, we demonstrated that the Asn-7.49 is important for the interaction between M(3)R and ARF1 and also for the formation of the ARF/Rho/β γ signaling complex, a complex that might determine the rapid activation and desensitization of PLD. Overall, these results indicate that the NPxxY motif of the M(3) muscarinic acetylcholine receptor acts as key conformational switch for receptor signaling and multiprotein complex formation. 相似文献
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Elliot Meyerowitz the Biology Department, Caltech, and a member of the Board of Directors of the ISPMB, has been named Fellow of the American
Academy of Arts and Science. 相似文献