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1.
Summary We examined the effect in rats of 2 months of streptozotocin-induced diabetes mellitus on relaxation and contraction of aortas in vitro. A further diabetic group was treated from time of diabetes induction with a 1% dietary supplement of vitamin E. Diabetes caused a 26.5% deficit (p<0.001) in maximum endothelium-dependent relaxation to acetylcholine in phenylephrine-precontracted aortas. This was 64.3% attenuated (p<0.01) by vitamin E treatment; maximum relaxation was not significantly altered compared to non-diabetic rats. Vitamin E treatment of non-diabetic rats did not significantly affect acetylcholine-induced relaxation. Diabetes or treatment did not significantly alter acetylcholine sensitivity. Endothelium-independent relaxation response to glyceryl trinitrate was not affected by diabetes or vitamin E treatment, indicating that vascular smooth muscle responses to nitric oxide remained unaltered. There was a 35.4% reduction in the maximum contractile response to phenylephrine with diabetes (p<0.05) which was unaffected by vitamin E treatment. The data suggest that the chronic deficit in nitric oxide-mediated endothelium-dependent relaxation in diabetes depends largely upon excess activity of reactive oxygen species. Treatment with vitamin E to increase free radical scavenging specifically protected vascular endothelium although it had no effect on deficits in vascular smooth muscle contractile responses.Abbreviations NO Nitric oxide - ARI aldose reductase inhibitor - ACH acetylcholine - GTN glyceryl trinitrate - GSH reduced form of glutathione - EC50 effective concentration for 50% of the maximal response  相似文献   
2.
A 72-year-old fisherman who was positive for the HCV antibody developed an annular, erythematous, infiltrated lesions on sun-exposed areas. The lesions were diagnosed as annular elastolytic giant cell granuloma both clinically and histologically. Topical corticosteroid and cryotherapy with liquid nitrogen for several months failed to improve the lesions. We then started dapsone, a known anti-oxidant, at 50 mg/day. A month later, the margins of the erythematous lesions faded, and the infiltration gradually decreased. No recurrence has been observed for one year after the start of the therapy. Anti-oxidative therapy appears to be effective for annular elastolytic giant cell granuloma and could be an alternate therapy for refractory granulomatous disease.  相似文献   
3.
我们用哈白兔以3%凝固气油致25%Ⅲ°烧伤休克持续了3h复苏的动物模型研究了丹参、维生素E、抗氧化剂协同治疗烧伤休克的作用,效果显著。第5天SOD活性和MDA值均达到伤前水平,提高了动物存活时间。各项生化指标和病理证实,该组实验动物脏器无明显病变,说明联合用药,不仅可以有效的清除氧自由基,还能拮抗脂质过氧化作用,对脏器有较好的保护作用。  相似文献   
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5.
目的探讨维生素E在体内外的应激损伤。方法体外实验:人肝RBL细胞系根据H_2O_2损伤及损伤前后给予维生素E分为4组,对照组(C)、H_2O_2损伤组(Ec)、H_2O_2损伤前(Eb)及后(Ea)给维生素E组;体内实验:将20只清洁级雄性Wistar大鼠分为对照组和大及小剂量维生素E组,每天进行一次35和15 mg/kg溶液2 m L灌胃,连续3 d。体外实验应用MTT和TUNEL法检测细胞存活率和凋亡率,免疫印迹和免疫组化方法检测细胞中NF-κB、Hsp-70、Bcl-2、Bax及caspase-3的表达水平;体内实验应用生化法检测3和6 d后血浆内T-AOC、SOD、GSH和MDA的水平。结果 H_2O_2损伤组(Ec)细胞凋亡率增加(P0.01),细胞内Bax、Hsp-70、NF-κB及caspase-3显著升高(P0.01),而Bcl-2显著下降(P0.01),维生素E干预后能显著缓解上述变化(P0.01),H_2O_2损伤前干预效果优于后干预。灌胃后3 d血浆中T-AOC、SOD、GSH的水平增高,MDA降低(P0.01),6 d后其相关指标变化更加显著(P0.05)。结论维生素E可通过调节人肝RBL细胞相关蛋白表达水平和Wistar大鼠血浆中抗氧化酶体系而发挥抗氧化作用。  相似文献   
6.
硫代葡萄糖苷及异硫氰酸酯的抗癌和抗氧化作用进展   总被引:1,自引:1,他引:0  
目的为硫代葡萄糖苷及异硫氰酸酯的合理利用、功能性保健产品开发和抗癌辅助药物的研制提供依据。方法归纳总结近10年硫代葡萄糖苷和异硫氰酸酯的文献,对其在植物体的分布、理化性质、抗癌和抗氧化机制等方面进行详细阐述。结果硫代葡萄糖苷及其水解产物异硫氰酸酯具有良好的抗癌和抗氧化活性,可以预防和治疗多种癌症,对于由空气污染引发的呼吸系统及肺部疾病也具有良好的疗效;硫代葡萄糖苷及异硫氰酸酯可以清除血管和机体的自由基,保护心脑血管,延缓衰老。结论硫代葡萄糖苷及异硫氰酸酯开发成功能性保健产品和抗癌辅助药具有广阔的市场前景。  相似文献   
7.
Introduction: The current review aimed to outline the functions of the renin angiotensin system (RAS) in the context of the oxidative stress-associated liver disease.

Areas covered: Angiotensin II (Ang II) as the major effector peptide of the RAS is a pro-oxidant and fibrogenic cytokine. Mechanistically, NADPH oxidase (NOX) is a multicomponent enzyme complex that is able to generate reactive oxygen species (ROS) as a downstream signaling pathway of Ang II which is expressed in liver. Ang II has a detrimental role in the pathogenesis of chronic liver disease through possessing pro-oxidant, fibrogenic, and pro-inflammatory impact in the liver. The alternative axis (ACE2/Ang(1-7)/mas) of the RAS serves as an anti-inflammatory, antioxidant and anti-fibrotic component of the RAS.

Expert commentary: In summary, the use of alternative axis inhibitors accompanying with ACE2/ Ang(1-7)/mas axis activation is a promising new strategy serving as a novel therapeutic option to prevent and treat chronic liver diseases.  相似文献   

8.
目的 建立以抗氧化和抗炎效应为指标的生脉注射液质量评价方法。方法 以水溶性维生素E(Trolox)和N-硝基-L-精氨酸甲酯(L-NAME)作为对照药,采用三硝基苯肼(DPPH)法和一氧化氮(NO)检测试剂盒对其抗氧化效应和对脂多糖(LPS)诱导单核巨噬细胞RAW264.7释放NO的抑制能力进行测定,将样品换算为相应浓度的对照药,对其方法学和生物效应进行控制和评价。结果 各批次样品均具有较好的抗炎和抗氧化效应,精密度高,重复性好;各批次样品在抗氧化能力方面不存在较大差异,在抗炎能力方面样品2和样品8与其他样品存在较大差异。结论 建立的方法可以准确评价生脉注射液的抗氧化和抗炎效应。  相似文献   
9.
Aster spathulifolius, Coreopsis drummondii, Chrysanthemum morifolium, Chrysanthemum boreale, Chrysanthemum indicum and Rudbeckia laciniata var. hortensis had 30–70 mg gallic acid equivalents (GAE)/g dw of the total phenolic contents. Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and reducing powers of tested Compositae plant extract appeared to be linear and consistent with total phenolic/flavonoids compound contents in the same manner with DPPH radical scavenging activity. R. laciniata (200 µg/mL) inhibited nitric oxide (NO) production to approximately 92.8% from lipopolysaccharide (LPS)-stimulated macrophage cells. Although the total phenolic/flavonoids contents and antioxidant activity of R. laciniata is low compared with other Compositae plants, R. laciniata shows the superior inhibitory activity against NO biosynthesis from LPS-induced macrophage cells. For antiobesity activity, C. boreale, C. morifolium and C. drummondii might act to accelerate lipid degradation and to decrease lipid synthesis in 3T3-L1 adipocyte cells, and C. indicum, A. spathulifolius and R. laciniata extract had antiobesity activity to inhibit lipid synthesis in 3T3-L1 adipocyte cells.  相似文献   
10.
目的对3个不同产地山银花和金银花中绿原酸、总黄酮含量及抗氧化活性进行分析,并比较之间的差异。方法对绿原酸提取条件进行优化,最佳提取条件为65℃下60%乙醇溶液按料液比1∶20超声提取30 min;总黄酮最佳提取条件为65℃下用60%甲醇溶液按料液比1∶10超声提取30 min。分别采用高效液相色谱法和紫外分光光度法对样品的绿原酸和总黄酮进行含量测定,并用DPPH自由基清除率来检测山银花、金银花的抗氧化活性。结果建立了良好的绿原酸和总黄酮含量分析方法,绿原酸在0.119~1.190 mg/m L内线性关系良好,r2为0.999 2(n=6);总黄酮在8.48~50.88μg/m L内线性关系良好,r2为0.999 5(n=6)。湖南产地山银花绿原酸量、总黄酮量及自由基清除率分别为3.99%、13.43%、62.41%。重庆产地山银花绿原酸量、总黄酮量及自由基清除率分别为3.29%、10.08%、51.48%。广西产地金银花绿原酸量、总黄酮量、自由基清除率分别为2.55%、7.10%、39.51%。结论提出了结合化学成分分析和抗氧化性活性来比较不同产地山银花和金银花之间区别的分析方法,从"谱-效"结合思路,为山银花和金银花质量控制及鉴别提供一种新的模式。  相似文献   
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