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11.
Epigallocatechin-3-gallate from green tea negatively affects swine granulosa cell function 总被引：2，自引：0，他引：2
The use of herbs as additives in livestock nutrition as an alternative to antibiotics is becoming a new goal in animal production. It is known that green tea exerts antimicrobial activity owing to specific flavonoid compounds named catechins, primarily represented by epigallocatechin-3-gallate (EGCG). Remarkably, despite many potential benefits of green tea and EGCG consumption, it is also important to get an insight on the possible reproductive-related consequences of feeding supplementation. To this purpose, granulosa cells were harvested from follicles > 5mm and treated with 5 and 50 microg/ml of EGCG in order to evaluate the effects on the main parameters of granulosa cell function: steroidogenesis, by measuring progesterone and estradiol-17beta production, and proliferation, one of the major feature of ovarian follicular growth. Moreover, as the genesis of new vessels has been demonstrated to be fundamental for follicle development, we evaluated the effect of EGCG on the production of the main angiogenetic factor, VEGF, by swine granulosa cells. Finally, since reactive oxygen species (ROS) might be involved in the control of female reproductive activity, we studied the effect of EGCG on superoxide anion (O2-) and hydrogen peroxide (H2O2) production by swine granulosa cells and on the activity of the scavenging enzyme superoxide dismutase (SOD). EGCG significantly (p < 0.05) inhibited proliferation, steroidogenesis, VEGF and O2- production by swine granulosa cells; on the contrary, H2O2 levels and SOD activity were stimulated (p < 0.05) by the catechin. Therefore, since our data demonstrate that EGCG has a negative effect on reproductive performances in swine, feeding supplementation should be carefully considered. 相似文献
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Gioacchino Calapai Fabio Firenzuoli Antonio Saitta Francesco Squadrito Maria R. Arlotta Giuseppina Costantino Giuseppina Inferrera 《Fitoterapia》1999,70(6):1474
The effects of repeated oral administration of 2.5–20 mg/kg of two Citrus aurantium fruit extracts standardized to different concentrations of synephrine (4 and 6%, respectively) on food intake, body weight gain, arterial blood pressure, electrocardiogram (ECG) and mortality have been investigated in the rat. C. aurantium administration significantly reduced food intake and body weight gain. However, mortality (not observed in controls) was present in all C. aurantium treated groups. Arterial blood pressure was not modified, but ECG alterations (ventricular arhythmias with enlargement of QRS complex) were evident in animals treated with both extracts. Our data indicate that, in the rat, antiobesity effects of C. aurantium are accompanied by toxic effects probably due to cardiovascular toxicity. 相似文献
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Alessandra F.M. Viu Marco A.O. Viu Armando R. Tavares Fabio Vianello Giuseppina P.P. Lima 《Scientia Horticulturae》2009
The present work evaluated the development of different Curcuma longa L. explants (leaves basis, root tips and ancillary buds from rhizome) stimulated by exogenous polyamines, combined with naphtalen-acetic acid (NAA) or with 6-benzyl-aminopurine (BAP), to produce callus and its subsequent differentiation. The explants, isolated from field plants, were previously subjected to a basic cleaning method and were inoculated onto Murashige and Skoog culture medium (MS) [Murashige, T.S., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiologia Plantarum 15, 473–497] supplemented with NAA (2.0 mg L−1). Buds were subjected to different treatments, with or without 5.0 and 10.0 mmol L−1 exogenous polyamines (mixture of putrescine:spermine:spermidine, 1:1:1) combined with NAA. The calluses obtained were transferred into the same medium, supplemented with the mixture of polyamines combined with BAP, in order to induce plant differentiation. For C. longa, buds were the most efficient explants for callus induction (p < 0.05). The application of exogenous polyamines (5.0 and 10.0 mmol L−1) produced the most developed callus, with numerous roots. The medium supplemented with 10 mmol L−1 polyamine mixture, combined with BAP, induced good regeneration, producing vigorous plants and excellent shoot formation.Polyamines addition promoted the formation of callus, roots and leaves, representing an important factor in the determination of indirect organogenesis in C. longa L., and putrescine content may be considered a valuable marker of the differentiation process in this specie, as well as the enzyme peroxidase. 相似文献
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Increased nitrogen-use efficiency of a short-rotation poplar plantation in elevated CO(2) concentration 总被引：1，自引：0，他引：1
Calfapietra C Angelis Pd Gielen B Lukac M Moscatelli MC Avino G Lagomarsino A Polle A Ceulemans R Mugnozza GS Hoosbeek MR Cotrufo MF 《Tree physiology》2007,27(8):1153-1163
We estimated nitrogen (N) use by trees of three poplar species exposed for 3 years to free air CO(2) enrichment (FACE) and determined whether the CO(2) treatment affected the future N availability of the plantation. Trees were harvested at the end of the first 3-year rotation and N concentration and content of woody tissues determined. Nitrogen uptake of fine roots and litter was measured throughout the first crop rotation. The results were related to previously published variations in soil N content during the same period. We estimated retranslocation from green leaves and processes determining N mobilization and immobilization, such as mineralization and nitrification, and N immobilization in litter and microbial biomass. In all species, elevated CO(2) concentration ([CO(2)]) significantly increased nitrogen-use efficiency (NUE; net primary productivity per unit of annual N uptake), decreased N concentration in most plant tissues, but did not significantly change cumulative N uptake by trees over the rotation. Total soil N was depleted more in elevated [CO(2)] than in ambient [CO(2)], although not significantly for all soil layers. The effect of elevated [CO(2)] was usually similar for all species, although differences among species were sometimes significant. During the first 3-year rotation, productivity of the plantation remained high in the elevated [CO(2)] treatment. However, we observed a potential reduction in N availability in response to elevated [CO(2)]. 相似文献
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The possible role played by hypoxia and vascular endothelial growth factor (VEGF) in the regulation of follicular angiogenesis was studied in a three-dimensional fibrin gel model. Granulosa cells from follicles >5mm were subjected to normoxia (19% O2), partial (5% O2) or total (1% O2) hypoxia and their culture media were collected and used to stimulate porcine Aortic Endothelial Cells (AOC) included in the fibrin matrix. A suspension of AOC on microcarrier beads was pipetted in a fibrinogen solution (1 mg/ml PBS) before the addition of 1250 IU thrombine (250 microl) to catalize the gel formation. Granulosa cell conditioned media were tested in the presence or absence of VEGF Trap R1R2 (150 ng/ml), a potent VEGF inhibitor, that had its efficacy tested by adding VEGF (100 ng/ml) to AOC culture. Endothelial cell proliferation was measured at 48, 96, 144, 192 h by means of Scion Image Beta. A significant (p < 0.01) increase of AOC proliferation at each time of measurement was induced by culture media from granulosa cells subjected to partial (except at the end of the first 48 h) and total hypoxia compared to control and normoxia conditions, and by VEGF. VEGF Trap significantly (p < 0.01) inhibited the stimulatory effect of media conditioned by granulosa cells cultured in hypoxic conditions. These data suggest that hypoxia stimulates angiogenic activity of granulosa cells possibly by means of VEGF which could represent the main effector in promoting endothelial cell proliferation. 相似文献
17.
Chiaretto G Zavagnin P Bettini F Mancin M Minorello C Saccardin C Ricci A 《Veterinary microbiology》2008,128(3-4):406-413
Salmonella strains isolated from poultry and poultry products over the period 2005-2006 have been investigated in order to ascertain the presence of extended spectrum cephalosporins (ESC) resistance. Twelve (ESC)-resistant isolates (n=1 S. Enteritidis, n=1 S. Braenderup and n=10 S. Livingstone) were characterized as SHV-12-positive. The multi-drug resistant S. Livingstone SHV-12-producing isolates, untypeable by pulsed-field gel electrophoresis (PFGE), showed a clonal relationship by random amplified polymorphic DNA (RAPD) analysis. The SHV-12 beta-lactamase is reported for the first time in Salmonella enterica strains isolated from poultry in Italy. The results suggest poultry as a source of Salmonella carrying extended spectrum beta-lactamases (ESBLs) genes and highlights the need of monitoring animal productions to prevent spreading of (ESC)-resistant strains. 相似文献
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Greco G Colarieti ML Toscano G Iamarino G Rao MA Gianfreda L 《Journal of agricultural and food chemistry》2006,54(18):6776-6782
The toxicity of olive mill wastewaters (OMW) is commonly attributed to monomeric phenols. OMW were treated in an aerated, stirred reactor containing agricultural soil, where the oxidative polymerization of phenols took place. In 24 h, OMW monomeric phenols decreased by >90%. This resulted in a corresponding reduction in phytotoxicity, as measured by germination tests with tomato and English cress seeds, and in microbial toxicity, as measured by lag phase duration in Bacillus cereus batch growth. Soil germination capability after irrigation with OMW was assessed in long-term pot experiments. The relative germination percentage of tomato was higher when the soil was irrigated with treated OMW rather than with untreated ones, although it was lower than the control (e.g., soil irrigated with distilled water). At longer incubation times, a complete recovery of the soil germination capability was achieved with treated, but not with untreated, OMW. 相似文献
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Iriti M Rabotti G De Ascensao A Faoro F 《Journal of agricultural and food chemistry》2003,51(15):4308-4314
The effects of ozone on bean plants pretreated with the SAR activator benzothiadiazole (BTH) have been investigated after fumigations with an acute dose of the pollutant (200 nL x L(-1) for 4 h), carried out at different times from BTH application. BTH pretreatment induced opposite effects on bean susceptibility to O(3), depending on the time elapsed before fumigation. When this time was only 1-2 days, bean plants were more susceptible to O(3) than untreated controls, showing rapid and extensive cell death in both palisade and spongy mesophyll. These damages appeared to be closely correlated with the amount and localization of H(2)O(2) in the leaf tissues. In BTH-pretreated, but not fumigated, plants, H(2)O(2) accumulation occurred in the cell walls and no dead cells were detected, whereas O(3) fumigation of untreated plants produced H(2)O(2) accumulation also inside some palisade mesophyll cells, causing their death. When BTH pretreatments were carried out 5-7 days before fumigation, plants appeared to be more tolerant to O(3) compared to untreated controls. Under these conditions, no visible symptoms of phytotoxicity were observed for at least 2 weeks after fumigation and no H(2)O(2) accumulation was detected. Biochemical assays showed a significant increase in the ascorbate (AA) level, taking place from the fifth to the seventh day after BTH treatment and unaffected by O(3) when given at these times. Ascorbate peroxidase (APX) activity appeared to decrease during the first 2 days after BTH treatment, and the decrease was somewhat enhanced by fumigation. On the contrary, guaiacol peroxidase (GuPX) activity was found to steadily increase up to the fifth day after BTH treatment but showed a bimodal trend upon fumigation. These results suggest that, during the first 1-2 days after BTH application, the H(2)O(2) level is enhanced by O(3) over a critical threshold for cell viability. However, in the absence of the pollutant, H(2)O(2) decreases in the following days under the effect of AA accumulation and increased GuPX activity. As GuPX is known to promote cell wall lignification and protein cross-linking, these effects would protect plasmalemma from O(3) irreversible damage, provided the priming by BTH has been fully developed. 相似文献