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1.
Hayek MG 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(3):301-302
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 相似文献
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动物中活性氧的产生及清除机制 总被引：10，自引：0，他引：10
各种氧化应激使动物细胞中积累大量的活性氧，从而导致畜禽生产性能的下降。动物体内有效清除活性氧的保护机制分为酶促和非酶促两类。酶促系统包括超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH—Px)和过氧化物酶(POD)。非酶促系统包括抗坏血酸(Vc)、谷胱甘肽、维生素E、类胡萝卜紊等。在动物日粮中添加抗氧化剂来维持抗氧化平衡，是集约化管理条件下维持畜禽良好生产性能和繁殖性能的一个重要方法。 相似文献
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VanSteenhouse JL 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1987,16(1):29-35
Free radicals are any molecules having an odd number of electrons. These molecules are highly reactive and can be generated as byproducts of normal metabolism as well as by exposure to a number of environmental factors including drugs, radiation and air pollutants. Due to the ubiquity of molecular oxygen, the oxygen metabolites superoxide anion, hydrogen peroxide, and the hydroxyl radical are frequently involved in both beneficial and detrimental free radical reactions. Intracellular enzymes and radical scavengers help to protect against tissue damage by these reactive metabolites. The extent of free radical damage to tissue depends on the nature of the radical produced and its site of generation. 相似文献
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Fuhrmann H Dobeleit G Bellair S Gück T 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2002,49(6):310-311
Rhodococcus equi is a well-characterized bacterial pathogen which lyses cell membranes with the help of cholesterol oxidase (CO). Survival in macrophages is warranted by its ability to resist reactive radicals via catalase and superoxide dismutase (SOD). Therefore, CO production in the absence or presence of 0.1 % cholesterol and sensitivity to exogenous hydrogen peroxide (H2O2) and superoxide anion (SOA) were tested in seven strains of R. equi in vitro. When R. equi strains were grown on agar plates with cholesterol, the bacterial growth [colony-forming units (cfu)/plate] did not increase significantly in comparison with the growth on plates without cholesterol. The activity of CO increased, significantly for extracellular CO. In subsequent experiments, R. equi strains grown on cholesterol were stressed with H2O2 or SOA so that approximately 10 % of cfu/plate survived. During stress induced by SOA, membrane CO and SOD activity increased significantly. Catalase activity increased 2-fold with H2O2 and 3-fold with SOA exposure. These data suggest that the presence of cholesterol induces CO in bacteria grown on agar plates. Catalase, SOD and even membrane-bound CO respond to reactive oxygen species. 相似文献
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The corpus luteum (CL) is a transient reproductive gland that produces progesterone (P), required for the establishment and maintenance of pregnancy. Although the regulation of bovine luteal function has been studied for several decades, many of the regulatory mechanisms involved are incompletely understood. We are far from understanding how these complex mechanisms function in unison. The purpose of this overview is to stress important steps of regulation during the lifetime of CL. In the first part, the importance and regulation of angiogenesis and blood flow during CL formation is described. The results underline the importance of growth factors especially of vascular endothelial growth factor A (VEGF A) and basic fibroblast growth factor (FGF-2) for development and completion of a dense network of capillaries. In the second part, the regulation of function by endocrine/paracrine- and autocrine-acting regulators is discussed. There is now more evidence that besides the main endocrine hormones LH and GH local regulators as growth factors, peptides, steroids and prostaglandins are important modulators of luteal function. During early CL development until mid-luteal stage oxytocin, prostaglandins and P itself stimulate luteal cell proliferation and function supported by the luteotropic action of a number of growth factors. The still high mRNA expression, protein concentration and localization of growth factors [VEGF, FGF-1, FGF-2, insulin-like growth factors (IGFs)] in the cytoplasm of luteal cells during mid-luteal stage suggest maintenance (survival) functions for growth factors. In the absence of pregnancy regression (luteolysis) of CL occurs. Progesterone itself regulates the length of the oestrous cycle by influencing the timing of the luteolytic signal prostaglandin F2alpha (PGF2alpha) from the endometrium. The cascade of mediators afterwards is very complex and still not well-elucidated. Evidence is given for participation of blood flow, inflammatory cytokines, vasoactive peptides (angiotensin II and endothelin-1), reactive oxygen species, angiogenic growth factors (VEGFs, FGFs, IGFs) and decrease of the classical luteotropic components as LH-R, GH-R, P450(scc) and 3beta-HSD. Despite of differences in methodology and interpretations, progress has been made and will continue to be made. 相似文献
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Takahashi M 《The Journal of reproduction and development》2012,58(1):1-9
Many factors affect development of mammalian preimplantation embryos in vitro. It is well known that in vitro development of bovine embryos is highly affected by culture condition including energy source, growth factors, pH or gas environment. Many efforts have been made towards the suitable environments which can successfully support embryo development in vitro. For a rapid growth and differentiation, embryo requires energy by utilizing ATP, NADPH with oxygen molecules. These energy substrates are produced from the electron transport chain in the mitochondria. In addition to energy production, reactive oxygen species (ROS) are also generated as by-product of such energy production system. ROS production is sensitively controlled by the balance of oxidizing and reducing status and affected by several antioxidant enzymes such as superoxide dismutase (SOD), Catalase, glutathione peroxidase (GPx) or low molecular weight thiols such as glutathione (GSH). Imbalance of oxidation and reduction causes production of excess ROS, which causes the developmental arrest, physical DNA damage, apoptosis induction or lipid peroxidation. Environmental oxygen condition during embryo culture also highly affects embryo development as well as intracellular redox balance. Several studies have revealed that regulation of intra- and extra- cellular reducing environment by reducing excess ROS by using antioxidants, reducing oxygen concentration are effective for improving embryo development. Also, recent studies have demonstrated the difference in gene expression affected by oxidative stress. This review briefly summarizes the effects of ROS and the role of redox balance on preimplantation embryos for improving the efficiency of in vitro production of mammalian embryos. 相似文献
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After surgical reposition of displaced organs (abomasum, uterus, intestines) restoration of blood flow and oxygen supply generates oxygen radicals and other reactive oxygen species. SOD indicates radical stress of the organism. Subject of the study was the question if SOD can be detected in blood serum samples of cows and if there are differences in SOD activity between healthy cows and cows with Dislocatio abomasi (DA). We also wanted to investigate the influence of breed "Schwarzbunte" with DA (16 left/5 rights). The samples were drawn before and 1, 3 and 24 post op. Ten healthy cows of the same breed were also examined (2 weeks and 4-6 weeks after calving). There are no significant differences between the SOD activity of healthy cows and cows with DA, but the SOD activity of cows with left DA is significant lower than the activity of cows with right DA. Post op. SOD activity decreases; 24 h after surgery cows with left but not with right DA show an increase of SOD activity similar to values before surgery. There is a close positive correlation between SOD activity and protein concentration as well as negative correlation to concentration of free fatty acids after surgery. The behaviour of SOD activity shows that the surgical replacement of the displaced abomasum can generate a depression of the antioxidative capacity of the organism. 相似文献
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为了揭示土壤重金属镉(Cd)对植物的毒害机理,采用温室盆栽试验方法,研究了不同浓度(0, 0.3, 1, 3, 10, 30和50 mg/kg)Cd污染土壤对石竹幼苗生长以及对抗坏血酸-谷胱甘肽(AsA-GSH)循环的影响。结果表明,石竹幼苗的分蘖数、株高和生物量表现出显著的“低促高抑”的现象,这缘于土壤Cd低浓度(≤1 mg/kg)胁迫和胁迫的初期,石竹叶片的超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、单脱氢抗坏血酸还原酶(MDAR)、脱氢抗坏血酸还原酶(DHAR)和谷胱甘肽还原酶(GR)等抗氧化酶活性提高,以抵抗体内逐渐增多的活性氧(ROS);随着Cd浓度的增加和镉胁迫时间的延长,石竹叶片中的超氧阴离子(O2-·)和过氧化氢(H2O2) 等ROS爆发,SOD、APX、MDAR、DHAR和GR等抗氧化酶活性迅速降低,抗坏血酸(AsA)和谷胱甘肽(GSH)含量减少,过多的ROS不能被石竹自身的抗氧化系统有效地清除,最终导致膜脂过氧化受到逆境伤害。另外,试验结果验证了APX是清除H2O2的重要酶,GR是生成GSH的重要酶,MDAR还原MDHAR是AsA-GSH循环中再生AsA的主要途径。 相似文献
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Auer DE 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1989,18(1):21-26
The role of oxygen-derived free radicals is considered critical to the etio-pathogenesis of equine inflammatory joint disease. In vivo, the superoxide radical in the joint may be derived either from activated polymorphonuclear leukocytes or from an ischemia/reperfusion cycle. In the presence of ferrous iron, it may generate the highly reactive hydroxyl radical (OH *). Predisposing factors may include synovitis, exercise-induced ischemia and minor traumatic injury to the joints. Unlike other inflammatory mediators, oxygen-derived free radicals may damage tissue directly and these reactive species could account for the tissue injury and insidious onset of equine exercise-induced degenerative joint disease. 相似文献
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Syota KAWAGUCHI Ryosuke SAKUMOTO Kiyoshi OKUDA 《The Journal of reproduction and development》2013,59(3):219-224
Luteoprotective mechanisms of luteinizing hormone (LH) involved in the maintenance of
bovine corpus luteum (CL) function have not been completely clarified. Since antioxidant
enzymes are well documented as antiapoptotic factors in the CL of many mammals, we
hypothesized that the luteoprotective action of LH is mediated by stimulating the local
production and action of antioxidant enzymes. To test the above hypothesis, in the present
study, we examined the mechanisms involved in the luteoprotective actions of LH. Cultured
bovine luteal cells obtained from the CL at the mid-luteal stage (days 8–12 of the estrous
cycle) were treated with LH (10 ng/ml), onapristone (OP; a specific progesterone receptor
antagonist, 100 μM) and diethyldithiocarbamate [DETC; an inhibitor of superoxide dismutase
(SOD), 100 μM] for 24 h. LH in combination with or without OP significantly increased the
mRNA and protein expressions of manganese SOD (Mn-SOD) and catalase (CATA) and SOD
activity. While LH alone significantly increased the mRNA and protein
expressions of SOD containing copper and zinc (Cu,Zn-SOD), OP in combination with or
without LH significantly decreased the mRNA and protein expressions of Cu,Zn-SOD. In
addition, Cu,Zn-SOD, Mn-SOD and CATA mRNA expressions were higher at the mid luteal phase
than the other luteal phases. LH in combination with DETC significantly decreased
LH-increased cell viability. The overall results suggest that LH increases cell viability
by LH-increased antioxidant enzymes, resulting in maintenance of CL function during the
luteal phase in cattle. 相似文献
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活性氧自由基在动物机体内的生物学作用 总被引：23，自引：3，他引：23
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。 相似文献
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Kleczkowski M Kluciński W Sikora J Zdanowicz M 《Polish journal of veterinary sciences》2004,7(3):233-240
The most important enzymatic mechanisms which protect an organism against oxidative stress are superoxide dismutase (SOD), peroxidase (Px), e.g. glutathione peroxidase (GSH-Px) and ascorbate peroxidase, catalase and glutathione reductase. Their activity depends on many trace elements. Enzymatic mechanisms, functioning under physiological conditions, prevent the spread of free radical reactions. New and reoccurring metabolic and infectious diseases of cattle emerge when there is a disproportion in the balance between reactive oxygen species and antioxidative enzymatic barrier. 相似文献
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Masanori KOBAYASHI Chie TSUZUKI Marika KOBAYASHI Hinano TSUCHIYA Yume YAMASHITA Kanako UENO Moe ONOZAWA Masato KOBAYASHI Eiichi KAWAKAMI Tatsuya HORI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1044
Oxidative stress owing to an imbalance between reactive oxygen species and antioxidants, such as coenzyme Q10 (CoQ10), is a major contributor to male infertility. We investigated the effects of the reduced form of CoQ10 (ubiquinol) supplementation on semen quality in dogs with poor semen quality. Three dogs received 100 mg of ubiquinol orally once daily for 12 weeks. Semen quality, serum testosterone, and seminal plasma superoxide dismutase (SOD) activity were examined at 2-week intervals from 2 weeks before ubiquinol supplementation to 4 weeks after the treatment. Ubiquinol improved sperm motility, reduced morphologically abnormal sperm, and increased seminal plasma SOD activity; however, it had no effect on testosterone level, semen volume, and sperm number. Ubiquinol supplementation could be used as a non-endocrine therapy for infertile dogs. 相似文献
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Oleuropein induces mitochondrial biogenesis and decreases reactive oxygen species generation in cultured avian muscle cells,possibly via an up‐regulation of peroxisome proliferator‐activated receptor γ coactivator‐1α 
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下载免费PDF全文 Motoi Kikusato Hikaru Muroi Yuichiro Uwabe Kyohei Furukawa Masaaki Toyomizu 《Animal Science Journal》2016,87(11):1371-1378