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81.
During the early stages of Kawasaki disease, a marked increase in oxygen-free-radicals (OFRs), which are produced by activated
polymorphonuclear cells, may induce coronary arteritis. Early use of high-dose intravenous gamma-globulin (IVIG) and aspirin
effectively blocked this deteriorating course of coronary arteritis; however, late use of IVIG, even using a high-dose schedule,
did not achieve the same efficacy. The causes and reactions to the scenario of IVIG refractoriness have rarely been mentioned
in the literature. We present an 11-month-old male infant with Kawasaki disease and deteriorating coronary arteritis owing
to late use of IVIG who showed dramatic responsiveness to the addition of α-tocopherol and ascorbic acid. We also discuss
the possible mechanism. 相似文献
82.
Stefek M Sotnikova R Okruhlicova L Volkovova K Kucharska J Gajdosik A Gajdosikova A Mihalova D Hozova R Tribulova N Gvozdjakova A 《Acta diabetologica》2000,37(3):111-117
Consistent with the postulated role of oxidative stress in the etiology of late diabetic complications, pharmacological interventions
based on biological antioxidants have been suggested. The aim of the present study was to investigate the effect of dietary
supplementation with the pyridoindole antioxidant stobadine on the myocardial antioxidant status and ultrastructure of streptozotocin-diabetic
rats. Diabetic male Wistar rats were fed for 32 weeks a standard diet or a diet supplemented with stobadine (0.05% w/w). Control
rats received a standard diet or stobadine-supplemented diet (0.16% w/w). Plasma levels of glucose, cholesterol and triglycerides
were increased significantly by diabetes. Activities of superoxide dismutase and catalase were markedly elevated in the diabetic
myocardium. Myocardial levels of conjugated dienes increased after eight months of diabetes, in spite of significantly increased
myocardial α-tocopherol and coenzyme Q9 content. The long-term treatment of diabetic animals with stobadine (i) reduced plasma cholesterol and triglyceride levels
yet left the severe hyperglycemia unaffected, (ii) reduced oxidative damage of myocardial tissue as measured by conjugated
dienes, (iii) reversed myocardial levels of α-tocopherol and coenzyme Q9 to near control values, (iv) reduced elevated activity of superoxide dismutase in the diabetic myocardium, and (v) attenuated
angiopathic and atherogenic processes in the myocardium as assessed by electron microscopy examination. These results are
in accordance with the postulated prooxidant role of chronic hyperglycemia and provide further evidence that development of
pathological changes in diabetic myocardium is amenable to pharmacological intervention by biological antioxidants.
Received: 7 June 2000 / Accepted in revised form: 27 November 2000 相似文献
83.
《International journal of food sciences and nutrition》2013,64(4):371-377
AbstractThe aim of this investigation was to produce an olive oil (OO) naturally enriched with antioxidants, recovering carotenoids, in particular lycopene, using an industrial by-product of tomato seeds and skin. For this purpose, a technological process in a low-scale industrial plant to co-mill olives and tomato by-product in de-frosted or freeze-dried forms was applied and studied with respect to control samples. Preliminary results obtained from two different experiments were carried out by 40?kg of cultivar Correggiolo olives and 60?kg of olive blends from different cultivars. In both the experiments, the co-milling showed significant enrichment in carotenoids, especially in lycopene (mean values of 5.4 and 7.2?mg/kg oil from defrosted and freeze-dried by-products, respectively). The experimental results demonstrated the possibility to obtain a new functional food naturally enriched in antioxidant compounds, which might be marketed as “OO dressing enriched in lycopene” or “condiment produced using olives and tomato by-product”. 相似文献
84.
《Nutrition (Burbank, Los Angeles County, Calif.)》2014,30(5):602-611
ObjectiveThe aim of the present study was to determine the effects of oral supplementation with l-glutamine plus l-alanine (GLN+ALA), both in the free form and l-alanyl-l-glutamine dipeptide (DIP) in endotoxemic mice.MethodsB6.129 F2/J mice were subjected to endotoxemia (Escherichia coli lipopolysaccharide [LPS], 5 mg/kg, LPS group) and orally supplemented for 48 h with either l-glutamine (1 g/kg) plus l-alanine (0.61 g/kg) (GLN+ALA-LPS group) or 1.49 g/kg DIP (DIP-LPS group). Plasma glutamine, cytokines, and lymphocyte proliferation were measured. Liver and skeletal muscle glutamine, glutathione (GSH), oxidized GSH (GSSG), tissue lipoperoxidation (TBARS), and nuclear factor (NF)-κB–interleukin-1 receptor-associated kinase 1 (IRAK1)–Myeloid differentiation primary response gene 88 pathway also were determined.ResultsEndotoxemia depleted plasma (by 71%), muscle (by 44%), and liver (by 49%) glutamine concentrations (relative to the control group), which were restored in both GLN+ALA-LPS and DIP-LPS groups (P < 0.05). Supplemented groups reestablished GSH content, intracellular redox status (GSSG/GSH ratio), and TBARS concentration in muscle and liver (P < 0.05). T- and B-lymphocyte proliferation increased in supplemented groups compared with controls and LPS group (P < 0.05). Tumor necrosis factor-α, interleukin (IL)-6, IL-1 β, and IL-10 increased in LPS group but were attenuated by the supplements (P < 0.05). Endotoxemic mice exhibited higher muscle gene expression of components of the NF-κB pathway, with the phosphorylation of IκB kinase-α/β. These returned to basal levels (relative to the control group) in both GLN+ALA-LPS and DIP-LPS groups (P < 0.05). Higher mRNA of IRAK1 and MyD88 were observed in muscle of LPS group compared with the control and supplemented groups (P < 0.05).ConclusionOral supplementations with GLN+ALA or DIP are effective in attenuating oxidative stress and the proinflammatory responses induced by endotoxemia in mice. 相似文献
85.
The oxidative modification hypothesis postulates that oxidative stress is one of the major factors in aging and the development of age-related disorders, including cardiovascular diseases. In this scenario, the oxidative modification of lipids, proteins and nucleic acids in vascular walls contributes to the etiology of cardiovascular disease, implying that consumption or therapeutic use of antioxidants could prevent the onset of such pathological disorders. Because of this, a number of studies have been conducted to address the question of whether cardiovascular diseases can be modulated by antioxidant treatment or consumption. Although some of the earliest data, collected in animal studies and epidemiologic studies have shown a measure of success, numerous clinical trials indicate that this approach is of minimal or no benefit. These conclusions represent a challenge to design more sensitive antioxidant trials in order to confirm or alter these conclusions. The focus of this review is on the benefits and disadvantages associated with the use of antioxidants, such as vitamins C and E, polyphenols, or antioxidant therapies, including hormone replacement therapy and iron reduction therapy, on overall vascular health. 相似文献
86.
Rosa-Maria Valls Aranzazu Soler Josefa Girona Mercedes Heras Maria-Paz Romero Maria-Isabel Covas Rosa Solà Lluis Masana Maria-Jose Motilva 《Journal of pharmaceutical and biomedical analysis》2010
The effect of repeated consumption of virgin olive oil on endogenous phenolic metabolites of fasting plasma is unknown. For this reason, we hypothesized that regular long-term virgin olive oil intake could have an indirect protection effect on the endogenous phenols. Thus, the aim of the study was to determine the phenolic profile of human plasma in a fasting state of long-term regular virgin olive oil consumers, using the fasting plasma of non-consumers as a natural control. Forty participants living in the area of Reus (Catalonia, Spain) were selected, 20 life-long regular consumers of virgin olive oil and a natural control of 20 non-consumers, the latter being Rumanians who dislike the taste of olive oil. The diet was obtained from 3-day food records. The results showed similar phenolic composition of fasting plasmas of the two volunteer groups. Of special interest is that more of the compounds quantified showed higher concentration in fasting plasma from habitual virgin olive oil consumers. The compounds were semi-quantified using caffeic acid as the calibration standard. The quantification of fasting consumer's plasma showed higher concentration of a hydroxyflavanone type compound (2.90 ± 0.04 μM vs 1.5 ± 0.04 μM) and a catecholamine derivative (0.70 ± 0.03 μM vs 0.56 ± 0.03 μM) than the plasma of non-consumers (P < 0.05). The results suggest an indirect protective mechanism of long-term regular virgin olive oil consumption related to the protection of the endogenous antioxidant system. 相似文献
87.
《Journal of microencapsulation》2013,30(3):247-254
AbstractBlackberry (Rubus fruticosus) juice possesses compounds with antioxidant activity, which can be protected by different biopolymers used in the microencapsulation. Therefore, the effects of cell wall material including maltodextrin (MD), Arabic gum (GA) and whey protein concentrate (WPC) were evaluated on the physicochemical and antioxidant properties of encapsulated blackberries using a spray-drying technique. Anthocyanin concentration, polymeric colour, total polyphenols, radical scavenging activity of the 1,1-diphenyl-2-picrilhydrazil radical, reducing power and the stability at different storage conditions were evaluated. GA and MD conferred a similar protection to the antioxidant compounds when the microcapsules were stored at low water activities (aw?<?0.515) in contrast to at a high moisture content (aw?>?0.902), whereas WPC presented a high protection. Therefore, the selection of the best wall material for blackberry juice encapsulation depends of the conditions of storage of the powder. 相似文献
88.
E. Bargagli C. Olivieri D. Bennett A. Prasse J. Muller-Quernheim P. Rottoli 《Respiratory medicine》2009,103(9):1245-1256
Oxidative stress is an imbalance between oxidants (reactive oxygen and nitrogen species) and antioxidants that may affect lipids, DNA, carbohydrates and proteins. The lung is continuously exposed to endogenous and exogenous oxidants (cigarette smoke, mineral dust, ozone, radiation). Reactive oxygen and nitrogen species are mainly produced by phagocytes as well as by polymorphonuclear, alveolar, bronchial and endothelial cells. A potential role of oxidative stress in the pathogenesis of diffuse lung diseases (particularly idiopathic pulmonary fibrosis) has been demonstrated. Increased oxidant levels and decreased antioxidant defences can contribute to the progression of idiopathic pulmonary fibrosis and other diffuse lung diseases.The growing number of papers on the different aspects of oxidant/antioxidant imbalance in diffuse lung diseases in the last decade reflects increasing interest in this topic and suggests that specific DLDs may be characterized by specific patterns of oxidation and antioxidant responses. The study of oxidative stress can provide insights into etiopathogenesis and favour the discovery of new treatments. In this review of the literature on oxidants and antioxidants in diffuse lung diseases, the focus is on idiopathic pulmonary fibrosis, sarcoidosis, pneumoconiosis and pulmonary fibrosis associated with systemic sclerosis. 相似文献
89.
Lead is a persistent and common environmental contaminant, which chiefly plays a significant role in modern industry. Coenzyme Q acts as electron and proton carrier in mitochondria and functions as an antioxidant in its reduced form (ubiquinol). To investigate the hazardous effects of lead on the coenzyme Q level, rats were injected i.p. with lead acetate (5 mg/kg b.wt. daily for 6 weeks). Our results showed that the levels of both oxidized (ubiquinone) and reduced (ubiquinol) forms of coenzyme Q9 and Q10 in serum, brain, liver and kidney of lead-treated rats are quite different depending on the organ tissue type. 相似文献
90.
目的 本文探讨中波紫外线(UVB)照射下海洋生物面膜对小鼠皮肤氧化损伤的保护作用和抗氧化酶的关系及其Bcl-2、NOS的表达。方法 建立UVB(辐照强度为5.15×10-2J·cm-2×30d)对昆明种无毛小鼠氧化损伤模型。昆明种无毛小鼠,随机分为双蒸水未照射组和UVB模型组(双蒸水对照组、10%MFP组、10%维生素C组)。电镜观察皮肤组织超微结构。并应用免疫组织化学的方法测定小鼠表皮细胞的Bcl-2蛋白表达、NOS的活性。酶法测定皮肤匀浆上清液中抗氧化酶(GSH-Px、SOD)活性和MDA的含量及总抗氧化能力(T-AOC)。结果 电镜下UVB损伤的对照组小鼠皮肤的表皮细胞胞质内可见空泡形成,真皮的成纤维细胞内可见囊泡状扩张的滑面内质网,粗面内质网等细胞器减少。①MFP组表皮细胞结构正常,成纤维细胞的粗面内质网增多,②MFP可以增强小鼠表皮细胞内Bcl-2蛋白的表达,并抑制NOS的免疫活性;③MFP可提高小鼠皮肤组织的总抗氧化能力、SOD活性,降低MDA含量,与维生素C的抗氧化作用一致。结论 海洋生物面膜与维生素C一样具有抗UVB氧化损伤的作用。其作用机制可能与海洋生物面膜增强Bcl-2的蛋白表达,降低NOS的活性,提高抗氧化酶含量、清除自由基有关。 相似文献