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101.
Oxidative damage in rat erythrocyte membranes following ethanol intake: effect of ethyl pyruvate 总被引:1,自引:0,他引:1
Gabbianelli R Cifani C Massi M Polidori C Falcioni G 《Chemico-biological interactions》2007,169(2):122-131
Alcoholic patients and experimental animals exposed to ethanol display biochemical signs of oxidative damage, suggesting a possible role of free radicals in causing some of the toxic effects of alcohol. The ester derivative, ethyl pyruvate (EP) is stable in solution and should function as an antioxidant and energy precursor. In the present study, the effect of ethanol intake on plasma membrane fluidity, lipid oxidation and antioxidant enzyme activities (GPx, CAT and SOD) were first evaluated. Secondly, the consequences of ethyl pyruvate treatment on the physico-chemical properties of erythrocyte plasma membranes were investigated. The results obtained demonstrate that ethanol induces an increase in lipid peroxidation, a reduction of GPx activity and fluidity in the hydrophilic-hydrophobic region of the bilayer, moreover an increase of fluidity in hydrophobic part of the plasma membrane was measured. When rats were treated with ethyl pyruvate a partially protective effect can be observed for the hydrophilic-hydrophobic region tested by Laurdan, while EP cannot restore the DPH anisotropy values to the control values. In summary, our data indicate that treatment with EP can only partially reduce ethanol plasma membrane perturbation. Since this study shows an ethyl pyruvate dose-dependent effect, it is important to consider the amount of EP required to maintain the right level of membrane fluidity and polarity. These results could be interesting in order to investigate if EP, due to its radical scavenging effect, can prevent oxidative damage induced by ethanol intake and can protect against injure related with ethanol intake. 相似文献
102.
103.
Andrea Matta Maurizio Tomasella Anna Valente 《Flexible Services and Manufacturing Journal》2007,19(3):173-194
This paper presents an optimal solution, based on Markov decision theory, for the problem of optimal capacity-related reconfiguration of manufacturing systems, under stochastic market demand. Both capacity expansion and reduction are considered. The solution quantitatively takes into account the effect of the ramp-up phenomenon, following each reconfiguration, on the optimal policy. A closed-form solution is presented for when product demand is independently and generally distributed over time. A real case concerning a flexible manufacturing line in the automotive sector is shown, to prove that ignoring the ramp-up effect in the decision process can lead to significant increases in overall costs. 相似文献
104.
Malolactic fermentation is a process that is influenced by various factors that can inhibit the growth of the malolactic bacteria. Inhibitory metabolites produced by yeast may have an important role in the correct development of malolactic fermentation. For these reasons, we have investigated the effects of such metabolites on the growth of malolactic bacteria under different environmental conditions, to aid in our understanding of the significance of these interactions in the wine-making environment. Our screening methods to detect interactions between yeast and malolactic bacteria showed a variable and wide diffusion of yeast inhibitory activity on the growth of the malolactic bacteria. However, this first approach to determine this inhibitory activity of yeast gave an overestimation when compared to the results obtained under actual wine-making conditions. The evaluation of malic acid consumption indicated that under inhibitory conditions a partial L-malic acid degradation was seen, indicating that the malolactic activity continued without bacterial growth. However, these yeast-inhibiting effects in addition to other environmental factors could cause a complete failure of malolactic fermentation. 相似文献
105.
106.
Francesca Giampieri Md Soriful Islam Stefania Greco Massimiliano Gasparrini Tamara Y. Forbes Hernandez Giovanni Delli Carpini Stefano Raffaele Giannubilo Andrea Ciavattini Bruno Mezzetti Luca Mazzoni Franco Capocasa Mario Castellucci Maurizio Battino Pasquapina Ciarmela 《Journal of cellular physiology》2019,234(5):7622-7633
Uterine leiom yomas are benign tumors highly prevalent in reproductive women. In thecurrent study, initially, we aimed to screen five different strawberry cultivars (Alba, Clery, Portola, Tecla, and Romina) to identify efficient cultivars in terms of phytochemical characterization and biological properties by measuring phenolic and anthocyanin content as well as antioxidant capacity, and by measuring apoptotic rate and reactive oxygen species (ROS) production in uterine leiomyoma cells. Next, we focused on the most efficient ones, cultivar Alba (A) and Romina (R) as well as Romina anthocyanin (RA) fraction for their ability to regulate oxidative phosphorylation (oxygen consumption rate [OCR]) glycolysis (extracellular acidification rate [ECAR]), and also fibrosis. Leiomyoma and myometrial cells were treated with a methanolic extract of A and R (250 μg/ml) or with RA (50 μg/ml) for 48 hr to measure OCR and ECAR, as well as gene expression associated with fibrosis. In the leiomyoma cells, RA was more effective in inducing apoptosis and increasing intracellular ROS levels, followed by R and A. In myometrial cells, all strawberry treatments increased the cellular viability and decreased ROS concentrations. Leiomyoma cells showed also a significant decrease in ECAR, especially after RA treatment, while OCR was slightly increased in both myometrial and leiomyoma cells. R and RA treatment significantly decreased collagen 1A1, fibronectin, versican, and activin A messenger RNA expression in leiomyoma cells. In conclusion, this study suggests that Romina, or its anthocyanin fraction, can be developed as a therapeutic and/or preventive agent for uterine leiomyomas, confirming the healthy effects exerted by these fruits and their bioactive compounds. 相似文献
107.
Ivano Rondelli Roberto Corsaletti Enrico Redenti Daniela Acerbi Maurizio Delcanale Gabriele Amari Paolo Ventura 《Chirality》1996,8(5):381-389
A new chiral derivatization procedure for the HPLC resolution of chiral catecholamines and structurally related compounds is described. The homochiral reagent, (+)-(R)-1-phenylethyl isocyanate (RPEIC), was added to separate and quantitate the enantiomers of rac-5,6-dihydroxy-2-methyl-aminotetralin, the main metabolite of rac-5,6-diisobutyryl-2-methyl-aminotetralin, a potent dopamine agonist, by reversed-phase HLPC analysis. To avoid catecholamine degradation in the basic reaction medium and to obtain the selective and quantitative derivatization of the amino group of the compound, the reversible complex formation between diphenylborinic acid (DPBA) and the catechol group, in alkaline medium, was performed before homochiral isocyanate addition. The RPEIC derivatization was completed in 30 min and then the DPBA complex was dissociated by adding dilute acid. The structure of intermediates and urea derivatives was confirmed by mass spectrometry. The use of an electrochemical detector, operating in redox mode, allowed HPLC quantitation of enantiomers at the nanogram level in plasma and urine. The derivatization procedure is also suitable for other catecholamine-related compounds. © 1996 Wiley-Liss, Inc. 相似文献
108.
M. Zoli L. F. Agnat K. Fuxe A. Cintra R. Grimaldi J. J. Vanderhaeghen P. Eneroth M. Goldstein 《Neurochemistry international》1988,13(4):499-508
Uridine was administered in the drinking water (0.5 mg/ml) in adult 6 month-old rats for 6 months. The mean daily dose of uridine was 12.5 mg/rat. The effects of this treatment on tyrosine hydroxylase, galanin, somatostatin, neuropeptide Y and cholecystokinin-like immunoreactivities were studied by means of semiquantitative immunocytochemistry using the peroxidase-antiperoxidase procedure in combination with image analysis. A decrease of somatostatin, cholecystokinin and galanin-like immunoreactivities in nerve terminals was observed in various brain areas of 12 month-old animals compared with 3 month-old animals, while the levels of tyrosine hydroxylase-like immunoreactivity were unchanged. Uridine-treated animals showed a decrease of galanin, neuropeptide Y and cholecystokinin-like immunoreactivities in nerve terminals of some diencephalic areas and an increase of cholecystokinin-like immunoreactivity in nerve terminals of most of the telencephalic brain areas in comparison with vehicle treated animals of the same age. It is suggested that the pyrimidine nucleoside uridine can affect the synthesis and/or degradation of mRNAs involved in the synthesis of neuropeptides via direct nuclear actions and/or indirect actions involving effects on receptor activated phosphoinositide metabolism. Uridine offers a new way to modulate central peptide synapses. 相似文献
109.
110.
AL Fracanzani L Valenti M Russello L Miele C Bertelli A Bellia C Masetti C Cefalo A Grieco G Marchesini S Fargion 《PloS one》2012,7(7):e41183