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51.
《Animal : an international journal of animal bioscience》2019,13(1):25-32
Recent studies suggest that the use of vegetable oils at expense of fish oil in aquaculture feeds might have potential negative effects on fish redox homeostasis and adiposity. Resveratrol (RESV) is a lipid-soluble phytoalexin present in fruits and vegetables with proven in vivo antioxidant function in animals. The present study aims to assess the potential use of RESV in Atlantic salmon feeds. To this end, post-smolt salmons with an initial BW of 148±3 g were fed four experimental diets for 15 weeks. A diet low in fish oil served as a control and was supplemented with 0, 0.5, 1.5 and 2.5 g/kg of RESV, respectively. The effect of the experimental diets on animal performance, tissue fatty acid composition, and the expression of genes encoding proteins involved in antioxidant signalling, lipid peroxidation, and metabolism were studied. Resveratrol significantly reduced feed intake and final BW of the salmon. Feeding RESV did not affect the sum of saturated and monounsaturated fatty acids or total lipids in the fillet. While the content of total polyunsaturated fatty acids was not affected, the percentages of some fatty acids in the liver and fillet were changed by RESV. Furthermore, in liver, the relative expression of glutathione peroxidase 4b, nuclear factor-like 2, and arachidonate 5-lipoxygenase remained unchanged across treatment groups. In conclusion, the negative impact of dietary RESV on FI and hence reduction of the BW discourages its inclusion in low fish oil diets for Atlantic salmon. 相似文献
52.
M. Shahid M.T. Javed S. Masood M.S. Akram M. Azeem Q. Ali R. Gilani F. Basit A. Abid S. Lindberg 《Journal of applied microbiology》2019,126(6):1708-1721
53.
54.
Antoni Sureda Pedro Tauler Antoni Aguiló Nuria Cases Isabel Llompart Josep A. Tur Antoni Pons 《Central European Journal of Biology》2007,2(1):56-70
Intense exercise induces inflammatory-like changes and oxidative stress in immune cells. Our aim was to study the effects
of antioxidant diet supplementation on the neutrophil inflammatory response and on the tocopherol associated protein (TAP)
expression after exhaustive exercise. Fourteen male-trained amateur runners were randomly divided in two placebo and supplemented
groups. Vitamins C (152 mg/d) and E (50 mg/d) supplementation were administrated to the athletes for a month, using an almond
based isotonic and energetic beverage. Non-enriched beverage was given to the placebo group. After one month, the subjects
participated in a half-marathon race (21 km-run). Neutrophil TAP mRNA expression and markers of the inflammatory response
were determined before, immediately after, and 3 h after finishing the half-marathon race. TAP expression increased after
exercise mainly in the neutrophils of the placebo group. Exercise induced an inflammatory response in both placebo and supplemented
groups, manifested with neutrophilia, increased creatine kinase and lactate dehydrogenase serum activities, neutrophil luminol
chemiluminescence and myeloperoxidase release. Plasma malondialdehyde only increased in the placebo group after exercise.
Diet supplementation with moderate levels of antioxidant vitamins avoids plasma damage in response to exhaustive exercise
without the effects on the inflammatory process. Neutrophil degranulation and increased tocopherol associated protein could
contribute to the neutrophil protection from the oxidative stress. 相似文献
55.
Roest PA van Iperen L Vis S Wisse LJ Poelmann RE Steegers-Theunissen RP Molin DG Eriksson UJ Gittenberger-De Groot AC 《Birth defects research. Part A, Clinical and molecular teratology》2007,79(3):231-235
BACKGROUND: Diabetes mellitus during pregnancy increases the risk for congenital heart disease in the offspring. The majority of the cardiovascular malformations occur in the outflow tract and pharyngeal arch arteries, where neural crest cells are essential for normal development. We studied the effects of specific exposure of neural crest cells to elevated glucose on heart development. Antioxidants reduce the damaging effect of glucose on neural crest cells in vitro; therefore, we investigated the effect of supplementing N-acetylcysteine in vivo. METHODS: Cardiac neural crest of HH 8-12 chicken embryos was directly exposed by a single injection in the neural tube with 30 mM D-glucose (or 30 mM L-glucose as a control). To examine the effect of a reduction in oxidative stress, we added 2 mM N-acetylcysteine to the injected D-glucose. RESULTS: Exposure of neural crest cells to elevated D-glucose-induced congenital heart malformations in 82% of the embryos. In the embryos injected with L-glucose, only 9% developed a heart malformation. As expected, all malformations were located in the outflow tract and pharyngeal arch arteries. The frequency of heart malformations decreased from 82% to 27% when 2 mM N-acetylcysteine was added to the injected D-glucose. CONCLUSIONS: These data are the first to confirm that the vulnerability of neural crest cells to elevated glucose induces congenital heart malformations. The fact that N-acetylcysteine limits the teratogenicity of glucose implies that its damaging effect is mediated by an increase of oxidative stress in the neural crest cells. 相似文献
56.
M. A. M. Abou-Seif 《Journal of biochemical and molecular toxicology》1996,11(3):133-138
Erythrocyte and plasma antioxidant enzyme activities and antioxidants as well as concentrations of total sulfate and thiocyanate were estimated in a group of healthy subjects and three groups of smokers (cigarette smokers, mixed tobacco smokers, and miscellaneous tobacco smokers). Plasma vitamin E, uric acid, ascorbic acid, ceruloplasmin, and urinary total sulfate concentrations were decreased, whereas dehydroascorbate and urinary thiocyanate concentrations were elevated in the three groups of smokers in comparison to the corresponding levels of the control subjects. On the other hand, erythrocyte superoxide dismutase and catalase as well as plasma superoxide dismutase activities were elevated in subjects of the three groups of smokers compared with the corresponding activity in subjects of the control group. Plasma catalase activity is statistically unaffected by smoking, but blood glutathione peroxidase activities were decreased in the three groups of smokers in comparison with the corresponding levels of the control group. There were also statistically meaningful differences between mean values of the antioxidant concentrations and the activities of the antioxidant enzymes in most of the smokers groups. © 1997 John Wiley & Sons, Inc. 相似文献
57.
【目的】明确沃尔巴克氏菌Wolbachia对茶尺蠖两近缘种杂交卵孵化的影响及相关机制。【方法】使用2.5 mg/mL四环素浸液处理1 min后的新鲜茶树叶片连续饲喂灰茶尺蠖Ectropis grisescens幼虫3代,建立不携带Wolbachia的灰茶尺蠖种群。通过携带和不携带Wolbachia的灰茶尺蠖成虫分别与小茶尺蠖E.obliqua成虫进行杂交,探究Wolbachia对二者杂交卵孵化的影响。同时利用iTRAQ技术检测并分析携带和不携带Wolbachia的灰茶尺蠖精子蛋白的差异。【结果】与自然携带Wolbachia的灰茶尺蠖相比,去除Wolbachia后的灰茶尺蠖与小茶尺蠖杂交卵孵化率从3.92%显著提高到56.20%,表明Wolbachia诱导胞质不亲合。精子蛋白差异分析显示,携带和不携带Wolbachia的灰茶尺蠖的精子蛋白中,共有128个蛋白显著差异表达,其中KEGG数据库注释到45个差异蛋白富集到鞘脂类代谢、唾液分泌、溶酶体、鞘脂信号通路和鞘糖脂生物合成等106个通路中,其中鞘脂类代谢通路中与神经酰胺合成相关的神经酰胺酶和磷酸酯酶显著上调表达。【结论】共生菌Wolbac... 相似文献
58.
Jada L-B Davis Mara OConnor Hannah Erlbacher Sarah L. Schlichte Hanna E. Stevens 《The Yale journal of biology and medicine》2022,95(1):87
Prenatal stress is a neuropsychiatric risk factor, and effects may be mediated by prenatal oxidative stress. Cell types in the brain sensitive to oxidative stress—cortical microglia and cortical and hippocampal interneurons—may be altered by oxidative stress generated during prenatal stress and may be neurobiological substrates for altered behavior. Our objective was to determine the critical nature of oxidative stress in prenatal stress effects by manipulating prenatal antioxidants. CD1 mouse dams underwent restraint embryonic day 12 to 18 three times daily or no stress and received intraperitoneal injections before each stress period of vehicle, N-acetylcysteine (200 mg/kg daily), or astaxanthin (30 mg/kg before first daily stress, 10 mg/kg before second/third stresses). Adult male and female offspring behavior, microglia, and interneurons were assessed. Results supported the hypothesis that prenatal stress-induced oxidative stress affects microglia; microglia ramification increased after prenatal stress, and both antioxidants prevented these effects. In addition, N-acetylcysteine or astaxanthin was effective in preventing distinct male and female interneuron changes; decreased female medial frontal cortical parvalbumin interneurons was prevented by either antioxidant; increased male medial frontal cortical parvalbumin interneurons was prevented by N-acetylcysteine and decreased male hippocampal GAD67GFP+ cells prevented by astaxanthin. Prenatal stress-induced increased anxiety-like behavior and decreased sociability were not prevented by prenatal antioxidants. Sensorimotor gating deficits in males was partially prevented by prenatal astaxanthin. This study demonstrates the importance of oxidative stress for persistent impacts on offspring cortical microglia and interneurons, but did not link these changes with anxiety-like, social, and sensorimotor gating behaviors. 相似文献
59.
Using the model of glutathione (GSH) depletion, possible role of GSH in the maintenance of blood-brain barrier (BBB) integrity was evaluated in rats. Administration (ip) of GSH depletors, diethyl maleate (DEM, 1–4 mmol/kg), phorone (2–3 mmol/kg) and 2-cyclohexene-1-one (CHX, 1 mmol/kg), to male adults was found to deplete brain and liver GSH and increase the BBB permeability to micromolecular tracers (sodium fluorescein and [14C]sucrose) in a dose-dependent manner at 2h. However, BBB permeability to macromolecular tracers such as horseradish peroxidase and Evan's blue remained unaltered. It was also shown that observed BBB permeability dysfunction was associated with brain GSH depletion. A lower magnitude of BBB increase in rat neonates, as compared to adults, indicated a possible bigger role of GSH in the BBB function of mature brain. The treatment with N-acetylcysteine, methionine and GSH provided a partial to full protection against DEM-induced brain (microvessel) GSH depletion and BBB dysfunction; however, the treatment with -tocopherol, ascorbic acid and turmeric were not effective. Our studies showed that cerebral GSH plays an important role in maintaining the functional BBB integrity. 相似文献
60.
Enhanced lipid peroxidation and decreased antioxidant defences have been defined in several diseases. In the present study, we aimed to evaluate the oxidative-antioxidative status of patients with cutaneous leishmaniasis (CL). Concentrations of erythrocyte lipid peroxidation (LPO), as an indicator for the oxidative status, reduced glutathione (GSH), glutathione peroxidase (GSH-Px) and serum vitamin C levels, as indicators for the antioxidative status, were measured. Seventy patients aged between 15 and 50 years (38 patients had active CL and 32 patients had healed CL) and 40 healthy controls aged between 19 and 50 years were included in the study. LPO and GSH of the patients with active CL were significantly higher (p < 0.001), whereas erythrocyte GSH-Px and serum vitamin C levels were lower (p < 0.001, p < 0.01 respectively) than those of healthy controls. There was a significant inverse correlation between LPO and serum vitamin C level (r=-0.32, p < 0.05) in active CL. No significant correlation of LPO, GSH, GSH-Px and serum vitamin C levels in control groups or in the group with healed CL was detected. In the light of our findings it is possible to conclude that patients having CL are affected by oxidative stress, which most likely induces the endogenous antioxidant system. An imbalance between the oxidant and antioxidant systems occurs and the suppressed antioxidants and increased lipid peroxidation may contribute to the progression of the disease. 相似文献