Antioxidation and Machnism of Lamiaceae species Extract in Monogastric Animals

动物在患病、应激或特殊生理条件下,机体内会大量产生自由基,自由基与机体内的脂质、DNA等产生反应,可对动物造成氧化损伤.唇形科植物提取物中的抗氧化物主要活性成分是酚类化合物,它和抗坏血酸及类胡萝卜素能够阻止自由基引发的氧化伤害.本文阐述了唇形科植物提取物对猪、鸡体外和体内抗氧化作用的实例与抗氧化功能,分析了其抗氧化作用机制.     

天然提取物在影响动物氧化应激中的研究进展

氧化应激是指机体内抗氧化系统失衡。在氧化应激条件下,动物体内产生大量自由基,当自由基含量超过机体抗氧化系统清除能力时,就会引起自由基堆积,造成氧化损伤,使动物生产性能下降,器官功能受损。近年来,天然提取物在影响动物氧化应激方面的研究受到广泛关注。天然提取物作为一种潜在的动物抗氧化应激剂,具有抗氧化、抗炎和免疫调节等作用,可通过减少自由基生成和提高抗氧化酶活性保护细胞免受氧化应激的损伤,在维持动物正常生理活动和繁殖性能等方面具有积极作用。文章通过对天然植物提取物中抗氧化活性成分及其作用途径进行综述,以期为新型抗氧化剂的开发和应用提供参考。     

连翘提取物抗氧化活性的研究进展

诸多因素可引起动物氧化应激,破坏体内自由基的动态平衡,从而产生一系列的氧化危害。添加天然抗氧化剂能保持动物机体内自由基的动态平衡。传统中药连翘具有抗菌、抗病毒、抗炎症、抗内毒素等药理活性。近年来的研究表明,连翘提取物具有良好的抗氧化活性。本文对连翘提取物抗氧化活性的研究做一综述。     

植物精油抗氧化作用机制研究进展

氧化应激是对动物生产造成巨大经济损失的常见问题之一,它是机体自由基产生增多或(和)清除能力下降,引起机体氧化系统和抗氧化系统紊乱,导致自由基在体内蓄积而引起的氧化损伤过程。氧化应激产生之后会对畜禽的生产性能和健康程度产生负面影响。因此,找到有效的外源性抗氧化剂对畜禽的健康生产有重要意义。植物精油作为天然抗氧化剂,具有安全、高效的特点,其在动物生产中的应用已成为研究热点。文章在简述自由基与氧化应激的基础上,对植物精油的抗氧化作用机制进行了分析和总结。     

活性氧自由基在动物机体内的生物学作用

自由基是近年来在基础医学和生命科学领域的研究热点,研究较多的以氧(O)、碳(C)和氮(N)为中心的活性基团。其中活性氧是机体内最常见自由基,也是近年来对其体内外生物学作用阐述最多的自由基种类之一。正常情况下,该类自由基在抗菌、消炎和抑制肿瘤等方面具有重要意义。但是,在疾病或某些外源性药物和毒物入侵后,机体抗氧化体系可能会发生紊乱,自由基代谢平衡因此失调,从而导致生物膜和大分子物质发生脂质过氧化损伤。文章对活性氧自由基在动物机体内的产生、性质和生物学作用,以及天然清除剂在机体内对自由基的抗氧化作用、自由基与疾病间的关系做了较全面综述。     

自拟药方"祛衣灵"对小鼠抗氧化腹胀的研究

在正常情况下,动物体内有一套完整的清除体内自由基的体系,包括谷胱甘肽过氧化物酶(GSH-Px)和超氧化物歧化酶(SOD).GSH-Px是生物机体抗氧化系统中重要的抗氧化分子,在抵抗氧自由基损伤、维持细胞蛋白质结构与功能和机体氧化还原平衡等方面发挥着重要的作用.SOD是动物机体内重要的抗氧化酶类,其作用是清除自由基和过...     

蚯蚓抗氧化提取液抗氧化作用研究

通过构建超氧阴离子自由基和羟基自由基体系以及脂蛋白多不饱和脂肪酸(PUFA)过氧化体系,测定蚯蚓抗氧化提取物在邻苯三酚自氧化体系中对超氧阴离子自由基、Fenton反应体系中对羟基自由基的清除作用及脂蛋白PUFA过氧化体系中对脂质体的抗氧化作用.通过对成年小鼠按时定量地灌喂蚯蚓抗氧化提取物,测定其血液和肝脏抗氧化酶活性及丙二醛(MDA)含量,检测蚯蚓抗氧化提取物在成年小鼠体内的抗氧化能力.结果显示,蚯蚓抗氧化提取物在体外自由基体系中具有较强的清除自由基的作用,且对脂质体氧化也有较强的抑制作用;在动物试验中,不同浓度的蚯蚓抗氧化提取物对成年小鼠血液及肝脏的SOD、CAT、GSH-PX活性的升高和MDA含量的减少均有不同程度的影响,并且以10倍稀释的蚯蚓抗氧化提取物影响最显著(P＜0.05),能有效降低小鼠体内的脂质过氧化水平并且防止体内抗氧化酶受自由基诱导的氧化损伤,提高抗氧化酶的活性.     

植物提取物的抗氧化功能

植物提取物是指经过一定工艺由植物中提取而来的天然活性成分的总称,主要分为植物多酚、天然色素、生物碱、植物多糖等4类。除生物碱外,其余三类植物提取物表现出对自由基的源头抑制与直接清除两种作用,并可提高机体抗氧化酶系的活性,因而在机体抗氧化方面具有突出作用。文章介绍了常见植物提取物及其抗氧化机理方面的研究,旨在为植物提取物在畜禽生产中的研究与应用提供参考。     

植物提取物在家禽抗氧化上的应用

植物提取物作为安全、有效、无残留的饲料添加剂已经得到越来越多的使用与重视,原因是其具有抗氧化、抗菌、促生长等多种对养殖业有益的作用。在养禽行业,鸡肉、鸡蛋等禽产品在贮藏过程中极易受到氧化而发生变质,而植物提取物可以有效地延长禽产品的贮藏时间。本文主要综述了植物提取物在肉鸡和蛋鸡上的抗氧化作用以及其体内和体外的作用机制,为以后植物提取物在家禽抗氧化上的应用研究提供依据。     

植物缩合单宁抗氧化作用机制的研究进展

体外和体内试验研究表明,植物缩合单宁具有显著的抗氧化生物活性。以往研究多关注缩合单宁对机体抗氧化酶活性的影响,近年来发现,缩合单宁通过启动Keap1-Nrf2/ARE抗氧化信号通路,上调抗氧化酶及相关因子基因表达而发挥抗氧化作用。缩合单宁亦能够与动物肠道菌群发生互作,通过促进抗氧化细菌增殖,抑制有毒有害微生物生长的方式,增强机体抗氧化状态。文章综述了缩合单宁的抗氧化作用机理研究进展,以期为植物提取物缩合单宁作为新型饲料添加剂的开发与应用提供参考。     

Potential for control of oxidative injury by administration of antioxidants in veterinary medicine

Cellular metabolism results in the production of reactive oxygen species otherwise known as free radicals. When not kept under control these molecules cause damage to various compartments in cells. These molecules are kept in check with antioxidant compounds that can be endogenous to cells or are present in the diet. When this balance is in the favor of reactive oxygen species then the physiological condition is considered to be in oxidative stress, which can lead to oxidative injury in various tissues. There has been a lot of interest in the effects of free radicals and the various degenerative diseases. This interest has lead to theories such as the free radical theory of aging, which states that aging is the accumulation of damage over time that leads to degenerative diseases. This has lead to a host of interest in the interaction of oxidative damage and certain disease states and how antioxidants may be beneficial in helping to modulate various disease states. In order to understand the potential for controlling oxidative injury in veterinary medicine, one needs to understand the cellular processes that reactive oxygen species and antioxidant compounds play in the body. It is usually thought that oxidative injury results in oxidative damage to the lipid, protein, and DNA components of cells. This damage results in alterations in cellular function. Various antioxidant compounds function to scavenge free radicals before they are able to damage the various cellular components     

围产期奶牛氧化应激、抗氧化防御系统及其与机体炎症反应的关系

氧化应激诱导机体自由基的产生是有氧代谢的一个组成部分。活性氧(reactiveoxygenspecies,ROS)是机体正常代谢过程和某些白细胞群体在疾病防御过程中产生的。越来越多的研究表明,机体组织和细胞产生的氧化损伤会直接或间接诱导许多疾病的发生,进而影响动物健康和福利。高产奶牛的生产性能在一定程度上可通过补充抗氧化剂来优化。概述了氧化应激的研究进展,综述了围产期奶牛氧化应激、抗氧化防御系统及其与炎症反应的关系,以期为进一步揭示抗氧化剂预防免疫功能障碍和宿主组织氧化损伤的分子机理,避免围产期奶牛发生由氧化应激诱导的代谢病和临床型疾病提供新思路。     

Introduction to oxidative stress and mitochondrial dysfunction

Oxidative stress and mitochondrial dysfunction are discussed in this article. Mitochondria are the major producers of free radicals and the major target of oxidative damage. Oxidative stress is simply the elevation of free radicals (reactive oxygen species/reactive nitrogen species) found in cells that accumulate to higher than normal levels. Excessive or inappropriate oxidative stress damages cells and tissues, specifically mitochondria, cell membranes, DNA, proteins, and lipids.     

Nutraceuticals, aging, and cognitive dysfunction.

Decline in cognitive function that accompanies aging in dogs might have a biological basis, and many of the disorders associated with aging in canines might be preventable through dietary modifications that incorporate specific nutraceuticals. Based on previous research and the results of laboratory and clinical studies, antioxidants might be one class of nutraceutical that benefits aged dogs. Brains of aged dogs accumulate oxidative damage to proteins and lipids, which can lead to dysfunction of neuronal cells. The production of free radicals and lack of increase in compensatory antioxidant enzymes might lead to detrimental modifications to important macromolecules within neurons. Reducing oxidative damage through food ingredients rich in a broad spectrum of antioxidants significantly improves, or slows the decline of, learning and memory in aged dogs; however, determining which compounds, combinations, dosage ranges, when to initiate intervention, and long-term effects constitute critical gaps in knowledge about this subject.     

Keap1-Nrf2/ARE信号通路及其在畜禽抗氧化中的研究进展

正常生理状态下，动物体内自由基的产生和清除处于稳定的动态平衡，但发生氧化应激时，体内自由基产生的量超过自身清除能力，引起氧化系统和抗氧化系统的失衡，造成氧化损伤。而Keap1-Nrf2/ARE信号通路的激活在预防氧化应激引起的细胞和组织损伤、维持氧化还原平衡和蛋白质稳态以及调节炎症方面具有关键作用。Keap1是Nrf2的胞浆抑制蛋白，在正常生理状态下，Nrf2与Keap1结合而发生泛素化和蛋白酶体降解，使细胞核内Nrf2的含量维持在一个相对较低的水平。在氧化应激条件下，Keap1对Nrf2的泛素化和降解的能力减弱，细胞核中Nrf2积聚，Nrf2与抗氧化反应元件（ARE）结合后启动下游一系列保护性基因的表达，使机体从氧化应激状态恢复到正常的生理状态。氧化应激参与多种病理生理变化，对畜禽的生产性能、生长发育、繁殖性能、肉品质等有负面影响，Keap1-Nrf2/ARE信号通路是细胞内最重要的抗氧化应激通路之一，对动物的健康保护极其重要。作者总结了Keap1-Nrf2/ARE信号通路的基本结构和活化机制及其在畜禽抗氧化中的研究进展，阐述了其在提高畜禽的抗氧化、抗炎能力和在肉品质中的重要作用，以期为缓解当前畜禽业中严重的氧化应激和炎症提供理论依据。     

Erythrocyte osmotic fragility test as the measure of defence against free radicals in rabbits of different age

Peroxidation of the unsaturated bonds of membrane lipids increases fragility and cellular lysis of red blood cells. Erythrocyte susceptibility to the free radicals (peroxyl radicals) generated in vitro by 2,2'-azo-bis(2-amidinopropane) hydrochloride (AAPH) was evaluated and expressed as 50% maximal haemolysis time (HT50) in 3 groups of rabbits of different age. Erythrocytes of 1.5-month-old rabbits were more sensitive to free radicals than those of 3.5- and 6-month-old ones. In the three groups, significant negative correlation (r = -0.8 to -0.98) between the lipid peroxidation rate (thiobarbituric acid reactive substances; TBARS concentration) in blood plasma and the erythrocyte resistance to free radicals was found. This result suggests that the plasma antioxidant defence system is interrelated with that of the red blood cells and that the erythrocytes can be a good model for studies of oxidative stress. The simple haemolysis test reflecting the free radical defence can be useful for evaluating the antioxidant properties of various compounds.     

Influence of hypothyroidism on lipid peroxidation, erythrocyte resistance and antioxidant plasma properties in rabbits

The effect of hypothyroidism on some oxidative stress parameters is reported. Moderate hypothyroid state was induced in two groups of female rabbits (3 and 12 months old) by giving 50 mg/kg body weight (BW) of propylthiouracil (PTU) per os for 6 days and 20 mg/kg BW of methimazole (MMI) for further 14 days. Serum T4 and T3 concentrations decreased by about 38-40 and 32-36%, respectively. The induced hypothyroidism resulted in a significant decrease in the serum concentration of the lipid peroxidation end-product malondialdehyde, as measured by the thiobarbituric-acid assay. Erythrocytes of hypothyroid animals exhibited higher resistance to oxidative stress, while submitted to free radicals generator 2,2'-azo-bis(2-amidinopropane) hydrochloride (AAPH) in vitro. Using two detector systems (phospholipid liposomes and deoxyribose), sensitive to either organic or inorganic oxygen radical damage, the ability of euthyroid and hypothyroid rabbit plasma to protect against oxygen radicals was evaluated. The plasma of hypothyroid animals showed about 20% higher ability to protect against iron-binding organic radicals, but about 50% lower chain-breaking antioxidant activity. The antioxidant capacity of plasma against inorganic radicals was not affected by hypothyroidism. In conclusion, the results show that thyroid hormones modulate the free-radical-induced oxidative damage of lipids and that hypothyroidism offers some protection against lipid peroxidation.     

微生物源性抗氧化剂对大鼠繁殖损伤的修复作用研究

本研究以脂多糖(LPS)作为自由基的诱发剂,微生物源性抗氧化剂作为自由基的清除剂,探讨自由基对大鼠繁殖性能的损伤及抗氧化剂的修复作用。将64只70日龄SD大鼠随机分成4组,每组16只,雌雄对半。对照组和损伤模型组饲喂基础日粮,抗氧化剂组和损伤修复组饲喂基础日粮并添加0.8 mL/d.只微生物源性抗氧化剂。损伤模型组和损伤修复组腹腔注射1 mg/kg LPS,对照组和抗氧化剂组注射等量的生理盐水,研究微生物源性抗氧化剂对雌鼠和雄鼠繁殖性能的影响。结果表明,注射LPS的雌鼠雌二醇浓度下降,受孕率降低,雄鼠精子数目、精子活动率和a级精子数显著降低。日粮中添加微生物源性抗氧化剂使雌鼠生育综合指数明显提高,血清中雌二醇含量升高,雄鼠精子数目增加,精子运动能力增强,断奶时仔鼠的数量和存活率提高。与损伤模型组相比,损伤修复组可一定程度提高大鼠的生育状况。结果提示,注射LPS导致大鼠产生氧化应激,对机体生殖机能造成损伤,微生物源性抗氧化剂具有提高大鼠繁殖性能并一定程度修复繁殖损伤的作用。     

Oxidative stress, aging, and central nervous system disease in the canine model of human brain aging.

Decline in cognitive functions that accompany aging in dogs may have a biologic basis, and many of the disorders associated with aging in dogs may be mitigated through dietary modifications that incorporate specific nutraceuticals. Based on previous research and the results of laboratory and clinical studies, antioxidants may be one class of nutraceutical that provides benefits to aged dogs. Brains of aged dogs accumulate oxidative damage to proteins and lipids, which may lead to dysfunction of neuronal cells. The production of free radicals and lack of increase in compensatory antioxidant enzymes may lead to detrimental modifications to important macromolecules within neurons. Reducing oxidative damage through food ingredients rich in a broad spectrum of antioxidants significantly improves, or slows the decline of, learning and memory in aged dogs.