Peroxidation

过氧化
  • 文章类型: Journal Article
    本研究旨在研究足球训练对血小板膜脂肪酸水平和抗氧化维生素的长期影响。44名受试者分为足球运动员(SP;n=22;20.86±0.36岁)和对照组(CG;n=22;21.23±0.49岁)。血小板膜的脂肪酸,去饱和率,评估脂质过氧化指数和血小板内维生素C和E水平.SP在多不饱和脂肪酸18:3:3(α-亚麻酸)中获得较低的值,20:5:3(二十碳五烯酸)和22:6:3(二十二碳六烯酸)(p<0.05)。SP的去饱和指数Δ5较高(p<0.05),它们具有较高的脂质过氧化指数20:4:6(花生四烯酸)/16:0(棕榈酸)(p<0.05)。SP中维生素E和C的血小板值也较高(p<0.01)。ω6/ω3指数呈正相关(p<0.05),去饱和指数Δ5(p<0.05),脂质过氧化指数20:4:6/16:0和血小板内维生素E和C(p<0.01)与身体活动水平。此外,脂肪酸24:0(二十四酸)呈负相关,16:1(棕榈油酸),根据身体活动的程度,20:3:6(二十碳二烯酸)和18:3:3(α-亚麻酸)(p<0.05)。定期的长期足球训练可以改变脂肪酸的浓度,例如24:0、16:1、18:6、20:3:6、18:3:3、20:5:3、26:6:3血小板膜中的3和ω3PUFA。
    This research aimed to study the long-term effects of soccer training on platelet membrane fatty acid levels and antioxidant vitamins. Forty-four subjects divided into soccer players (SP; n = 22; 20.86 ± 0.36 years) and a control group (CG; n = 22; 21.23 ± 0.49 years) participated in the study. The fatty acids of the platelet membrane, the rates of desaturation, lipid peroxidation indexes and intra-platelet levels of vitamins C and E were assessed. SP obtained lower values in polyunsaturated fatty acids 18:3:3 (alpha-linolenic acid), 20:5:3 (eicosapentaenoic acid) and 22:6:3 (docosahexaenoic acid) (p < 0.05). The desaturation index ∆5 was higher in SP (p < 0.05), and they had a higher lipid peroxidation index 20:4:6 (arachidonic acid)/16:0 (palmitic acid) (p < 0.05). Vitamin E and C platelet values were also higher in SP (p < 0.01). There were positive correlations in the ω6/ω3 index (p < 0.05), desaturation index ∆5 (p < 0.05), lipid peroxidation index 20:4:6/16:0 and intra-platelet vitamins E and C (p < 0.01) with the level of physical activity. In addition, there were inverse correlations in fatty acids 24:0 (lignoceric acid), 16:1 (palmitoleic acid), 20:3:6 (eicosadienoic acid) and 18:3:3 (alpha-linolenic acid) (p < 0.05) depending on the degree of physical activity. Regular long-term soccer training could modify the concentration of fatty acids such as 24:0, 16:1, 18:6, 20:3:6, 18:3:3:3, 20:5:3, 26:6:3 and ω3 PUFAs in the platelet membrane.
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  • 文章类型: Journal Article
    必须在整个生命周期中优化健康和健康。活性氧(ROS)的积累与衰老的标志有关,抑制ROS的产生可能会延缓衰老,同时增加健康寿命。脂质和脂质介质(脂质的衍生物)越来越被认为是组织和细胞功能中的中心分子,并且易于过氧化;因此与衰老有关。与衰老过程有关的脂质类别包括固醇,甘油磷脂,鞘脂和多不饱和脂肪酸的氧化产物,但这些尚未转化为临床。需要进一步的机理研究来理解衰老过程中的脂质类别。脂质组学,脂质物种在代谢和功能方面的系统水平表征,通过纵向研究,可能会提供一个重要而有用的生物年龄剖面工具。健康个体中不同年龄的脂谱可以用作健康衰老的脂质生物标志物,并可能整合以开发基于脂质的衰老时钟(脂质时钟)。脂质时钟的潜力包括预测未来的发病率或死亡率,这将促进精准健康的长寿医学。
    It is imperative to optimise health and healthspan across the lifespan. The accumulation of reactive oxygen species (ROS) has been implicated in the hallmarks of ageing and inhibiting ROS production can potentially delay ageing whilst increasing healthy longevity. Lipids and lipid mediators (derivatives of lipids) are becoming increasingly recognized as central molecule in tissue and cellular function and are susceptible to peroxidation; hence linked with ageing. Lipid classes implicated in the ageing process include sterols, glycerophospholipids, sphingolipids and the oxidation products of polyunsaturated fatty acids but these are not yet translated into the clinic. Further mechanistic studies are required for the understanding of lipid classes in the ageing process. Lipidomics, the system level characterisation of lipid species with respect to metabolism and function, might provide a significant and useful biological age profiling tool through longitudinal studies. Lipid profiles in different ages among healthy individuals could be harnessed as lipid biomarkers of healthy ageing with potential integration for the development of lipid-based ageing clock (lipid clock). The potential of a lipid clock includes the prediction of future morbidity or mortality, which will promote precision and healthy longevity medicine.
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  • 文章类型: Journal Article
    亚硝基铁络合物是非常多因素的药理学试剂。这些化合物已被证明在治疗心血管和肿瘤疾病方面特别有效。我们评估并比较了含血红蛋白系统中四硝基铁配合物(TNIC)与硫代硫酸盐配体的抗氧化活性以及二硝基铁配合物(DNIC)与谷胱甘肽(DNIC-GS)或磷酸盐(DNIC-PO4-)配体的抗氧化活性。研究的影响包括叔丁基过氧化氢在血红蛋白(Hb)氧化过程中产生自由基中间体,Hb的氧化改性,亚硝基铁配合物的抗氧化性能。测量鲁米诺化学发光表明,与DNIC-PO4-相比,TNIC的抗氧化作用更高。DNIC-GS在某些浓度下没有表现出抗氧化活性或发挥促氧化作用,这可能是由硫基自由基形成引起的。TNIC和DNIC-PO4-有效地保护Hb血红素基团免受有机氢过氧化物的分解。DNIC-GS对血红素组没有任何保护作用;然而,它废除了氧铁蛋白生成。TNIC比DNIC更有效地抑制Hb多聚体形式的形成。因此,在含Hb的系统中,TNICs比DNICs具有更明显的抗氧化活性。
    Nitrosyl iron complexes are remarkably multifactorial pharmacological agents. These compounds have been proven to be particularly effective in treating cardiovascular and oncological diseases. We evaluated and compared the antioxidant activity of tetranitrosyl iron complexes (TNICs) with thiosulfate ligands and dinitrosyl iron complexes (DNICs) with glutathione (DNIC-GS) or phosphate (DNIC-PO4-) ligands in hemoglobin-containing systems. The studied effects included the production of free radical intermediates during hemoglobin (Hb) oxidation by tert-butyl hydroperoxide, oxidative modification of Hb, and antioxidant properties of nitrosyl iron complexes. Measuring luminol chemiluminescence revealed that the antioxidant effect of TNICs was higher compared to DNIC-PO4-. DNIC-GS either did not exhibit antioxidant activity or exerted prooxidant effects at certain concentrations, which might have resulted from thiyl radical formation. TNICs and DNIC-PO4- efficiently protected the Hb heme group from decomposition by organic hydroperoxides. DNIC-GS did not exert any protective effects on the heme group; however, it abolished oxoferrylHb generation. TNICs inhibited the formation of Hb multimeric forms more efficiently than DNICs. Thus, TNICs had more pronounced antioxidant activity than DNICs in Hb-containing systems.
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  • 文章类型: Journal Article
    由于鸡的脂肪代谢受损而导致的过度脂肪沉积是家禽业中的主要问题。营养干预是有效的解决方案,但目前的选择是有限的。一种安全的植物化学物质,芦丁,对动物有积极的影响,但其对家禽脂质代谢的影响尚不清楚。因此,本研究旨在探讨芦丁对鸡蛋品质的影响,血清生物化学,脂肪沉积,峰后蛋鸡的脂质过氧化和肝脏脂质代谢。将360只太行蛋鸡(49周龄)随机分为5组,饲喂基础日粮(对照组,0%)和补充300(0.03%)的基础饮食,600(0.06%),900(0.09%),和1200(0.12%)毫克芦丁/公斤饲料,分别。结果表明,饲粮芦丁组蛋壳强度显著(p<0.05)提高,而蛋黄百分比(p<0.05),总胆固醇(TC)(p<0.01)和蛋黄脂肪比(p<0.01)线性降低(p<0.05)。重要的是,饲粮芦丁降低血清甘油三酯(TG)和TC水平,降低腹部脂质沉积和肝脏指数(p<0.05),并同时降低肝脂质(TG,TC,和游离脂肪酸)积累(p<0.05)。还发现总抗氧化能力和超氧化物歧化酶活性增加(p<0.05),丙二醛水平降低(p<0.05)。同时,肝脂肪酶的活性,肝脏中乙酰辅酶A羧化酶和苹果酸酶均降低(p<0.05)。日粮芦丁也增加(p<0.05)脂肪酸氧化相关基因的表达(肉碱棕榈酰转移酶1,过氧化物酶体增殖物激活受体α,法尼醇X受体)。此外,它降低了脂肪酸合成基因(甾醇调节元件结合蛋白-1c,乙酰辅酶A羧化酶α,硬脂酰辅酶A去饱和酶1)(p<0.05)。总之,日粮中添加芦丁(0.06-0.12%)改善了高峰后蛋鸡的脂肪代谢和肝脏抗氧化能力,这些积极的变化在一定程度上改善了鸡蛋的品质。
    Excessive fat deposition due to impaired fat metabolism in chickens is a major problem in the poultry industry. Nutritional interventions are effective solutions, but current options are limited. A safe phytochemical, rutin, has shown positive effects in animals, but its effect on lipid metabolism in poultry remains unknown. Hence, this study is to investigate the effects of rutin on egg quality, serum biochemistry, fat deposition, lipid peroxidation and hepatic lipid metabolism in post-peak laying hens. A total of 360 Taihang laying hens (49-week-old) were randomly divided into five groups and fed a basal diet (control group, 0%) and a basal diet supplemented with 300 (0.03%), 600 (0.06%), 900 (0.09%), and 1,200 (0.12%) mg rutin/kg feed, respectively. The results showed that eggshell strength was significantly (p < 0.05) higher in the dietary rutin groups, whereas yolk percentage (p < 0.05), total cholesterol (TC) (p < 0.01) and yolk fat ratio (p < 0.01) decreased linearly (p < 0.05) in the dietary rutin groups. Importantly, dietary rutin reduced serum triglyceride (TG) and TC levels, decreased abdominal lipid deposition and liver index (p < 0.05), and which concomitantly decreased hepatic lipid (TG, TC, and free fatty acid) accumulation (p < 0.05). An increase (p < 0.05) in total antioxidant capacity and superoxide dismutase activity and a decrease (p < 0.05) in malondialdehyde levels were also found. At the same time, the activities of hepatic lipase, acetyl-CoA carboxylase and malic enzyme in the liver were decreased (p < 0.05). Dietary rutin also increased (p < 0.05) the expression of fatty acid oxidation-related genes (carnitine palmitoyl transferase 1, peroxisome proliferator-activated receptor α, farnesoid X receptor). Additionally, it decreased fatty acid synthesis genes (sterol regulatory element binding protein-1c, acetyl-CoA carboxylase α, stearoyl-CoA desaturase 1) (p < 0.05). In conclusion, the addition of rutin (0.06-0.12%) to the diet improved the fat metabolism and increased liver antioxidant capacity in post-peak laying hens, and these positive changes improved egg quality to some extent.
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  • 文章类型: Journal Article
    甲状腺激素(TH)系统的破坏与野生动物和人类的各种不良健康结果有关。开发和验证能够测量甲状腺激素(TH)系统破坏的合适的体外测定法至关重要。这些测定对于遵守3R原则也是必不可少的,旨在取代化学评估中经常使用的离体测试。我们比较了适用于高通量筛选[Luminol和AmplexUltraRed(AUR)]的两种常用测定法,以评估甲状腺过氧化物酶的抑制作用(TPO,TH合成中的关键酶)使用几种细胞系和来自不同用途类别的21种化合物。由于所研究的来自人和大鼠甲状腺的细胞系显示出低或不可检测的TPO表达,我们开发了一系列过表达人类TPO蛋白的新型细胞系。基于高且稳定的TPO基因和蛋白质表达,HEK-TPOA7模型被优先用于进一步研究。值得注意的是,即使在没有TPO表达的Nthy-ori3-1和HEK293T细胞系中,Luminol测定法也检测到显着的过氧化物酶活性和信号抑制,揭示了它缺乏特异性。相反,AUR测定对TPO活性具有特异性。然而,尽管有不同的特异性,两种检测方法都鉴定出类似的过氧化抑制剂.超过一半的测试化学品具有不同的结构和不同的使用组引起TPO抑制,包括一些广泛的环境污染物,表明环境化学物质对TH合成的潜在影响。此外,在计算机上SeqAPASS分析证实了人类TPO在哺乳动物和其他脊椎动物类别中的高度相似性,提示HEK-TPOA7模型发现对其他脊椎动物的适用性。
    Disruption of the thyroid hormone (TH) system is connected with diverse adverse health outcomes in wildlife and humans. It is crucial to develop and validate suitable in vitro assays capable of measuring the disruption of the thyroid hormone (TH) system. These assays are also essential to comply with the 3R principles, aiming to replace the ex vivo tests often utilised in the chemical assessment. We compared the two commonly used assays applicable for high throughput screening [Luminol and Amplex UltraRed (AUR)] for the assessment of inhibition of thyroid peroxidase (TPO, a crucial enzyme in TH synthesis) using several cell lines and 21 compounds from different use categories. As the investigated cell lines derived from human and rat thyroid showed low or undetectable TPO expression, we developed a series of novel cell lines overexpressing human TPO protein. The HEK-TPOA7 model was prioritised for further research based on the high and stable TPO gene and protein expression. Notably, the Luminol assay detected significant peroxidase activity and signal inhibition even in Nthy-ori 3-1 and HEK293T cell lines without TPO expression, revealing its lack of specificity. Conversely, the AUR assay was specific to TPO activity. Nevertheless, despite the different specificity, both assays identified similar peroxidation inhibitors. Over half of the tested chemicals with diverse structures and from different use groups caused TPO inhibition, including some widespread environmental contaminants suggesting a potential impact of environmental chemicals on TH synthesis. Furthermore, in silico SeqAPASS analysis confirmed the high similarity of human TPO across mammals and other vertebrate classes, suggesting the applicability of HEK-TPOA7 model findings to other vertebrates.
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  • 文章类型: Journal Article
    聚氨酯(PU)产量的突然增加需要可行的废物回收方法。PU是最重要的塑料材料之一,具有广泛的应用;然而,氨基甲酸酯键的稳定性是化学回收中的一个主要问题。在这项工作中,模型氨基甲酸酯分子的终止反应,即N-苯基氨基甲酸甲酯(MPCate),用G3MP2B3复合量子化学方法进行了研究。我们的主要目标是深入了解氨基甲酸酯键终止的活力,并找到一种适用的化学回收方法。加氢,水解,甲醇分解,过氧化,糖酵解,氨解,在气相和冷凝相中都探索了用甲胺还原和用亚磷酸二甲酯终止的方法。在这些化学物质中,H2,H2O2和CH3NH2的降解显示出有希望的结果,具有较低的活化屏障和exragonic途径,特别是在水溶性中。实施这些有效的PU再循环方法还可以具有显著的经济效益,因为从反应获得的产物是工业上相关的物质。例如,苯胺和碳酸二甲酯可以在聚合物技术中重复使用,作为循环经济的潜在方法。随着进一步的潜在转变,还检查了MPCate的几种电离,包括电子捕获和分离,质子化/去质子化和与OH-反应。由于活化能相对较低,因此发现对氨基甲酸乙酯MPCate模型的碱性消化是有希望的。在理想情况下,氨基甲酸酯键的转化可能是一个酶促过程;因此,潜在的酶,如脂加氧酶,也被认为是过氧化的催化作用,和用于甲醇分解的脂肪酶。
    A sudden increase in polyurethane (PU) production necessitates viable recycling methods for the waste generated. PU is one of the most important plastic materials with a wide range of applications; however, the stability of the urethane linkage is a major issue in chemical recycling. In this work, termination reactions of a model urethane molecule, namely methyl N-phenyl carbamate (MPCate), are investigated using G3MP2B3 composite quantum chemical method. Our main goal was to gain insights into the energetic profile of urethane bond termination and find an applicable chemical recycling method. Hydrogenation, hydrolysis, methanolysis, peroxidation, glycolysis, ammonolysis, reduction with methylamine and termination by dimethyl phosphite were explored in both gas and condensed phases. Out of these chemicals, degradation by H2, H2O2 and CH3NH2 revealed promising results with lower activation barriers and exergonic pathways, especially in water solvation. Implementing these effective PU recycling methods can also have significant economic benefits since the obtained products from the reactions are industrially relevant substances. For example, aniline and dimethyl carbonate could be reusable in polymer technologies serving as potential methods for circular economy. As further potential transformations, several ionizations of MPCate were also examined including electron capture and detachment, protonation/deprotonation and reaction with OH-. Alkaline digestion against the model urethane MPCate was found to be promising due to the relatively low activation energy. In an ideal case, the transformation of the urethane bond could be an enzymatic process; therefore, potential enzymes, such as lipoxygenase, were also considered for the catalysis of peroxidation, and lipases for methanolysis.
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  • 文章类型: Journal Article
    胆红素(BR),血红素分解代谢的产物,在生物系统中起着至关重要的作用。尽管BR水平升高会导致高胆红素血症或黄疸,有越来越多的证据表明,较低的浓度显著降低了由BR的抗氧化功能引起的氧化应激介导的疾病的风险。我们在两个模型系统中研究了BR的自由基捕获能力,胶束和脂质体,在较宽的pH范围内。在pH<6.0时,BR表现为阻滞剂;然而,在pH≥6.0时,BR成为强自由基捕获抗氧化剂,与脂质过氧自由基(kinh)反应的速率常数在1.2×104M-1s-1至3.5×104M-1s-1的范围内,并且在脂质体系统中,BR的活性与α-生育酚相当。羧基的电离可能会促进这种转变,导致BR中的构象移位和改善水/脂质界面处的溶解度/定位。这是pH值对胆红素抗氧化活性作用的第一个实验证据,观察到的BR的pH依赖性自由基捕获能力具有实际意义,特别是在黄疸治疗中,光疗的目标是皮肤的弱酸性表面。对中性或碱性pH的微小调整可以增强BR的自由基捕获作用,从而减轻蓝光或紫光暴露引起的氧化应激。
    Bilirubin (BR), a product of heme catabolism, plays a critical role in biological systems. Although increased levels of BR result in hyperbilirubinemia or jaundice, there is increasing evidence that lower concentrations substantially decrease the risk of oxidative stress-mediated diseases due to antioxidant functions of BR. We studied the radical-trapping ability of BR in two model systems, micellar and liposomal, at a broad pH range. At pH < 6.0, BR behaves as a retardant; however, at pH ≥ 6.0, BR becomes strong radical trapping antioxidant, with rate constants for reaction with lipidperoxyl radicals (kinh) within the range from 1.2 × 104 M-1 s-1 to 3.5 × 104 M-1 s-1, and in liposomal system, the activity of BR is comparable to α-tocopherol. This transition is likely facilitated by the ionization of carboxyl groups, leading to a conformational shift in BR and improved solubility/localization at the water/lipid interface. This is the first experimental evidence of the role of pH on the antioxidant activity of bilirubin, and the observed pH-dependent radical-trapping ability of BR holds practical significance, particularly in jaundice treatment where light therapy targets the skin\'s weakly acidic surface. Minor adjustments toward neutral or alkaline pH can enhance radical-trapping action of BR, thereby mitigating oxidative stress induced with blue or violet light exposure.
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  • 文章类型: Journal Article
    长期暴露于镉(Cd)等潜在毒性元素(PTE)会通过产生氧化应激导致男性生殖毒性。螺旋藻最大节旋藻(AM)是一种蓝细菌,自古以来就因其高营养价值而被食用,近年来,由于它的抗病毒作用,保肝,低血糖,抗癌,和抗氧化作用,在其他人中。本研究旨在评价AM对Cd致生殖健康损害的影响。共有48只10周龄有性经历的雄性Wistar大鼠分为五组(n=8):对照组;媒介物(吐温水);氯化镉(CdCl2)5mg/kg;和三种剂量的AM(100、200和400mg/kg)CdCl25mg/kg。所有治疗均口服给药,每天一次,连续36天。最后,对性行为进行了评估,还有精液,睾丸,获得血液样本来分析精子质量,酶活性,和睾丸激素水平,分别。暴露于Cd的大鼠表现出性行为的减少,以及生殖健康的质量,和氧化应激的增加;而同时暴露于AMCd的大鼠显示出所有这些参数的改善。根据我们的结果,我们认为,AM发挥其作用的机制可能归因于藻胆蛋白的存在。这些化合物负责对元素如Cd发挥抗氧化作用和螯合作用。
    Chronic exposure to potentially toxic elements (PTEs) such as cadmium (Cd) leads to male reproductive toxicity through the generation of oxidative stress. Spirulina Arthrospira maxima (AM) is a cyanobacterium that has been consumed since ancient times for its high nutritional value, and in recent years for its antiviral, hepatoprotective, hypoglycemic, anticancer, and antioxidant effects, among others. This study aimed to evaluate the effects of AM against the damage to reproductive health induced by Cd. A total of 48 10-week-old sexually experienced male Wistar rats were distributed in five groups (n = 8): control; vehicle (tween-water); cadmium chloride (CdCl2) 5 mg/kg; and three doses of AM (100, 200 and 400 mg/kg) + CdCl2 5 mg/kg. All treatments were orally administered once a day for 36 consecutive days. At the end, sexual behavior was evaluated, and semen, testicle, and blood samples were obtained to analyze sperm quality, enzymatic activity, and testosterone levels, respectively. Rats exposed to Cd showed a decrease in sexual behavior, as well as in the quality of reproductive health, and an increase in oxidative stress; while rats exposed simultaneously to AM + Cd showed an improvement in all this parameters. Based on our results, we believe that the mechanism by which AM exerts its effect could be attributed to the presence of phycobiliproteins. These compounds are responsible for exerting an antioxidant effect and chelating effect on elements such as Cd.
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  • 文章类型: Journal Article
    蛋白质氨基酸侧链的氧化修饰是氧化应激的标志,它们通常被视为结构损坏。然而,氨基酸氧化也可能具有保护作用,并且可以用于调节或结构目的。这里,我们试图通过分析20个蛋白质氨基酸在动物中的整体氧化还原作用,在5种氧化负担增加的合理进化范式中分析它们的使用频率:(i)过氧化物酶体蛋白与所有蛋白,(ii)线粒体蛋白质与所有蛋白质,(iii)线粒体编码的呼吸链蛋白与所有线粒体蛋白,(iv)来自长寿动物的蛋白质与来自短命动物的蛋白质,和(v)来自有氧的蛋白质,自由生活的动物与来自兼性厌氧动物的动物。我们已经发现,在大多数比较中,在氧化条件下避免半胱氨酸是最显著和显著的变化。除了这种卓越的模式,只观察到本地信号,主要是蛋氨酸和谷氨酰胺的增加以及丝氨酸和脯氨酸的减少。因此,尽管某些类型的半胱氨酸氧化在二硫键形成和金属连接中起着重要作用,但似乎可以增强其蛋白质组范围的进化回避。所有其他氨基酸的氧化敏感性似乎通常没有问题,有时是有利的。
    Oxidative modifications of amino acid side chains in proteins are a hallmark of oxidative stress, and they are usually regarded as structural damage. However, amino acid oxidation may also have a protective effect and may serve regulatory or structural purposes. Here, we have attempted to characterize the global redox role of the 20 proteinogenic amino acids in animals by analyzing their usage frequency in 5 plausible evolutionary paradigms of increased oxidative burden: (i) peroxisomal proteins versus all proteins, (ii) mitochondrial proteins versus all proteins, (iii) mitochondrially encoded respiratory chain proteins versus all mitochondrial proteins, (iv) proteins from long-lived animals versus those from short-lived animals, and (v) proteins from aerobic, free-living animals versus those from facultatively anaerobic animals. We have found that avoidance of cysteine in the oxidative condition was the most pronounced and significant variation in the majority of comparisons. Beyond this preeminent pattern, only local signals were observed, primarily increases in methionine and glutamine as well as decreases in serine and proline. Hence, certain types of cysteine oxidation appear to enforce its proteome-wide evolutionary avoidance despite its essential role in disulfide bond formation and metal ligation. The susceptibility to oxidation of all other amino acids appears to be generally unproblematic, and sometimes advantageous.
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  • 文章类型: Journal Article
    人类精子的冷冻保存对于患有不育症的男性来说是必需的,他们不能产生用于授精的新鲜精液。然而,目前的ART冷冻保存方案与精子活力的丧失有关,活力和DNA完整性,被认为与氧化损伤的诱导和商业冷冻保护剂(CPAs)的毒性有关。预防或减轻这些损失将对ART期间的精子存活非常有益。因此,在这项体外研究中,脂质过氧化,活性氧的产生,运动特性,抗氧化能力,活力,在补充CPA的冷冻保存前和冷冻后检查精液样品中的DNA完整性。研究结果表明,添加CPA后,抗氧化能力降低了50%,伴随着活性氧的产生和脂质醛的形成显着增加。这些变化是,反过来,与精子活力降低相关,运动性和DNA完整性。抗氧化剂补充产生钟形的剂量反应曲线与白藜芦醇和维生素C,强调这些细胞对氧化和还原性应激的脆弱性。在最佳剂量下,维生素C能够显着增强活力并减少冷冻保存的人类精子中记录的DNA损伤。精子活力的改善没有达到统计学意义,可能是因为其他病理生理机制限制了抗氧化剂在挽救精子功能方面的潜在有效性。人类精子对还原性应激的脆弱性和精子冷冻损伤的复杂性将在创造下一代冷冻保护介质方面提出重大挑战。
    Cryopreservation of human spermatozoa is a necessity for males suffering from infertility who cannot produce fresh semen for insemination. However, current ART cryopreservation protocols are associated with losses of sperm motility, vitality and DNA integrity, which are thought to be linked to the induction of oxidative damage and the toxic properties of commercial cryoprotectants (CPAs). Preventing or mitigating these losses would be hugely beneficial to sperm survival during ART. Therefore, in this in vitro investigation, lipid peroxidation, production of reactive oxygen species, movement characteristics, antioxidant capacity, vitality, and DNA integrity were examined in semen samples both pre- and post-cryopreservation with CPA supplementation. The findings revealed a 50% reduction in antioxidant capacity with CPA addition, which was accompanied by significant increases in generation of reactive oxygen species and formation of lipid aldehydes. These changes were, in turn, correlated with reductions in sperm viability, motility and DNA integrity. Antioxidant supplementation generated bell-shaped dose-response curves with both resveratrol and vitamin C, emphasising the vulnerability of these cells to both oxidative and reductive stress. At the optimal dose, vitamin C was able to significantly enhance vitality and reduce DNA damage recorded in cryopreserved human spermatozoa. An improvement in sperm motility did not reach statistical significance, possibly because additional pathophysiological mechanisms limit the potential effectiveness of antioxidants in rescuing this aspect of sperm function. The vulnerability of human spermatozoa to reductive stress and the complex nature of sperm cryoinjury will present major challenges in creating the next generation of cryoprotective media.
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