猴头菇子实体对运动后细胞氧化损伤的保护作用

对猴头菇多糖样品进行了O₂^-、DPPH·、·OH的清除试验,试验结果显示,猴头菇子实体具有良好的清除多种自由基的能力,体外抗氧化性试验证明了猴头菇子实体具有良好的抗氧化活性,能够增强细胞的抗疲劳和抗衰老能力,对运动细胞氧化损伤具有一定的保护作用。     

Protective effect of melatonin on mitochondria of ischemic-reperfusion injuried myocardium

AIM and METHODS: To study the protective effect of melatonin on mitochondria of rat myocardium on the ischemia-reperfusion model in vivo, and discuss its mechanism in terms of oxygen free radical, calcium overload and energy metabolism. RESULTS and CONCLUSION: 10 mg/kg melatonin administered 5 min before reperfusion, which obviously reduced the content of malondialdehyde of myocardial mitochondria, increased the content of glutathione, inhibited calcium overload, protected the integrality in mitochondrial structure, promoted the recovery of ability in ATP synthesis after reperfusion, maintained the energy metabolism of the myocardium.     

二硫苏糖醇对海水胁迫下菠菜活性氧代谢及叶绿素荧光特性的影响

 以耐海水菠菜品种‘荷兰3号’为材料,采用水培方法,研究了二硫苏糖醇（DTT）对海水胁迫及甲基紫精（MV）诱导下菠菜活性氧代谢及叶绿素荧光特性的影响。结果表明,海水胁迫与MV处理一样,诱导菠菜叶片产生氧化胁迫,使超氧阴离子（）产生速率、过氧化氢（H₂O₂）含量和丙二醛（MDA）含量显著上升,叶绿素a（Chl.a）、叶绿素b（Chl.b）、总叶绿素[Chl.(a + b)]和类胡萝卜素（Car.）含量显著下降,最大光量子产量（F_v/F_m）、实际光量子产量（Yield）、电子传递速率（ETR）和光化学猝灭系数（q_P）显著降低,而非光化学猝灭系数（NPQ/4）显著上升;海水胁迫与MV处理下,由叶柄导入叶黄素循环活性抑制剂DTT,菠菜叶片活性氧（ROS）大量积累,导致光合色素降解加剧,F_v/F_m、Yield、ETR、NPQ、q_P进一步下降。上述结果表明,海水胁迫抑制了菠菜叶片叶黄素循环活性,降低了叶片非辐射能量耗散能力,加重了叶片ROS积累,从而导致光合色素含量降低,PSⅡ活性下降,电子传递速率降低,用于光化学反应的能量部分减少,光合作用受到严重影响,说明海水胁迫下叶黄素循环在保持菠菜叶片光合色素稳定和光合作用正常运转中发挥重要作用。     

Signaling pathways involved in mediating mitochondrial damage in diabetic kidney disease

Diabetic kidney disease （DKD） is one of the most common and serious chronic complications of diabetes and has gradually become the main cause of end-stage renal disease （ESRD）. As the center of energy and metabolism in cells, mitochondria have become the focus of the research on the pathogenesis of DKD in recent years. Current studies find that damage to mitochondria, such as DNA mutations, structural damage, oxidative stress imbalance, etc, leads to apoptosis of kidney cells, thus causing the loss of kidney function. In the process of mitochondrial damage, a series of important signaling pathways are involved, and exploring these signaling pathways would help us better understand the pathogenesis of DKD and find new therapeutic targets. In this article, the important signaling pathways associated with mitochondrial damage are reviewed.     

水杨酸对根际低氧胁迫八棱海棠幼苗活性氧代谢的影响

 采用营养液水培系统,以苹果砧木八棱海棠(Malus robusta Rehd.)为试材,用叶面喷施的方法,研究了外源水杨酸(salicylic acid ,SA)对根际低氧胁迫下八棱海棠叶片活性氧(ROS)代谢的影响。结果表明：低氧胁迫下八棱海棠叶片丙二醛(MDA)、超氧阴离子 (O₂)、过氧化氢(H₂O₂)、谷胱甘肽(GSH)含量和抗氧化酶活性均高于对照,而抗坏血酸(AsA)含量低于对照;外源SA明显抑制MDA和O₂的积累,显著增强超氧化物歧化酶(SOD)、过氧化物酶(POD)、抗坏血酸过氧化物酶(APX)和谷胱甘肽还原酶(GR)的活性。说明SA作为化学诱抗剂,可抑制低氧胁迫下苹果幼苗体内活ROS的产生,提高抗氧化酶的活性,降低膜脂过氧化水平,从而减轻低氧胁迫对植株的伤害。     

Characteristics of energy metabolism in brain mitochondria of rats exposed to hypoxia

AIM:To explore the characteristics of energy metabolism in brain mitochondria of rats exposed to acute and chronic hypoxia. METHODS: Animal grouping: Wistar rats were randomized into acute hypoxic group (AH), chronic hypoxic group (CH) and the control. Respiratory function, F₀F₁-ATPase activity, mitochondrial ATP, ADP and AMP contents and ATP production rate were measured respectively. RESULTS: In AH, brain mitochondrial respiratory state IV (ST₄) was increased, while respiratory control rate (RCR), mitochondrial ATP content, ATP production rate and F₀F₁-ATPase activity were decreased respectively. In CH, ST₄, RCR, mitochondrial ATP content and F₀F₁-ATPase activity were reversed partially.CONCLUSION: Acute hypoxia may impair brain mitochondria energy metabolism by way of depressing mitochondrial oxidative phosphorylation and ATP production and these parameters gain partial reablement during chronic hypoxia.     

Progress of silicon dioxiode induces liver cancer periphery fibrosis in experimental research

Therapeutic efficiency of advanced stage liver cancer is insufficiency, which has become the hot spot of research. Clinical observation found that prognosis of liver cancer with integrity amicula was better. It is generally accepted that silicon dioxiode (SiO2) can induce pulmonary fibrosis, resulting in the formation of pneumosilicosis. Use of SiO2 as embolism material induces hepatic fibrosis and forms the fibrosis amicula around the liver carcinoma, and then restrains the recurrence and metabasis of liver cancer, which has been turned into one of the aspect of liver carcinoma therapy. The possible mechanisms of inducing hepatic fibrosis by SiO2 are peroxidative damage by free radical, releasing of active cytokines, or inducing cell apoptosis and the activation of HSC etc.     

Taurine reduced oxygen free radical production induced by homocysteine in electron transport chain and homocysteine inhibites taurine transporter in mitochondria membrane

AIM: To observe effects of homocysteine and antagonized effects of taurine on electronic leakage and free radical production in myocardial mitochondria. METHODS: Myocardial mitochondria of rat heart was isolated, and was broken by supersonic wave to prepare submitochondria. Recombinant of succinic acid cytochrome c reductase was prepared with mitochondria of porcine heart. They were co-incubated with homocysteine and/or taurine with various concentration. The H₂O₂ and O₂^- were determined by chemiluminescence methods. The taurine transporter of heart mitochondria and its propert, and effects of homocysteine on its function were studied with glass filter. RESULTS: Homocysteine stimulated oxygen free radical production in heart mitochondria, submitochondria, and succinic acid cytochrome c in a concentration-dependent manner. Although taurine itself did not affect oxygen free radical production, taurine did inhibit oxygen free radical production in mitochondria, submitochondria and succinic acid cytochrome c in a concentration-dependent manner. Taurine transporters of Na⁺-dependent were existed in mitochondria membrane. Homocysteine inhibited taurine transtport in mitochondria in a concentration-dependent manner. CONCLUSIONS: Taurine inhibited electronic leakage and oxygen free radical production induced by homocysteine in electron transport chain. There were taurine transporters in mitochondria membrane, and transport functions of taurine transporter were inhibited by homocysteine.     

杧果果实响应1-MCP处理的数字基因表达谱分析

以‘台农1号’杧果为试材,用1–甲基环丙烯（1-MCP,1 μL · L-1）常温下处理12 h和未处理的果实为对照,通过数字基因表达谱（DGE）技术,寻找1-MCP处理对杧果贮藏影响的潜在关键基因。DGE数据分析结果表明,1-MCP处理与对照样品文库相比,共检测到7 350个差异表达基因。其功能主要涉及细胞壁代谢,激素调节,逆境胁迫应答,氧化损伤保护,能量代谢,蛋白质折叠,泛素化和蛋白酶体途径介导的细胞程序性死亡,成熟与衰老调控等。利用实时定量PCR（qRT-PCR）技术对DGE部分数据进行验证,检测了其中6个较有代表性的应答基因的差异表达。通过基因本体（Gene Ontology,GO）通路功能富集分析表明,1-MCP处理增加果实对逆境胁迫的抵抗能力,抑制物质和能量代谢,减少细胞内钙的流失并保护果实细胞。qRT-PCR技术数据支持RNA-Seq的检测结果。     

The antioxidative activity of a new compound from ginger

AIM:To assess the antioxidative activity of a new cyclic diaryheptanoid (compound 1) from ginger on free radical damage. METHODS: Hemolysis, MDA levels of mice liver tissue homogenates, the conformation changes of irradiated PUC₁₈ were used as indices. RESULTS:Compound 1 significantly reduced the hemolysis of human red blood cells induced by H₂O₂ (P＜0.01) and MDA level in the liver of mice (P＜0.01), raised the percentage of the supercoil conformation of plasmid PUC₁₈ induced by[⁶⁰Co]γ-rays (P＜0.05 or P＜0.01).CONCLUSION:Compound 1 had a good activity on suppressing oxygen free radical damage.     

Changes in oxidative damage, antioxidant enzyme activities and polyamine contents in leaves of grafted and non-grafted eggplant seedlings under stress by excess of calcium nitrate

The effect of 80 mmol L⁻¹ stress by excess of calcium nitrate [Ca(NO₃)₂] on biomass production, oxidative damage, antioxidant enzymes activities and polyamine contents in leaves of grafted and non-grafted eggplant (Solanum melongena L.) seedlings were studied, in which grafted plants were grafted on a salinity tolerant rootstock (Solanum torvum Swartz). The results showed that on the 15th day of treatment, the biomass production reduction of non-grafted seedlings was significantly higher than that of grafted seedlings. Under stress by excess of Ca(NO₃)₂, superoxide anion radical (O₂⁻) producing rate, electrolyte leakage percentage, contents of hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) of non-grafted seedlings were significantly higher than those of grafted seedlings, but activities of superoxide dismutase (SOD, EC 1.15.1.1), peroxidase (POD, EC 1.11.1.7), ascorbate peroxidase (APX, EC 1.11.1.11) and glutathione reductase (GR, EC 1.6.4.2) of grafted seedlings were significantly higher than those of non-grafted seedlings, moreover, contents of free, soluble conjugated and insoluble bound polyamines of grafted seedlings were significantly higher than those of non-grafted seedlings, and activities of diamine oxidase (DAO, EC 1.4.3.6) and polyamine oxidase (PAO, EC 1.5.3.3) of grafted seedlings were significantly lower than those of non-grafted seedlings. The possible roles of antioxidant enzymes and polyamines in protective mechanism of grafted eggplant seedlings to stress by excess of Ca(NO₃)₂ were discussed.     

壳寡糖诱导草莓细胞活性氧代谢的变化

 以草莓悬浮培养的细胞为对象, 研究了壳寡糖处理对活性氧代谢的效应。结果表明, 壳寡糖可诱导草莓悬浮培养细胞的活性氧迸发, 其峰值出现于20～30 min , 同时也可诱导活性氧清除酶活性上升,SOD 和CAT活性的最大值在处理后60～90 min。     

Effect of mild hypothermia on energy metabolism and hydroxyl radical production after cerebral ischemia/reperfusion in gerbils

AIM: To study the effect of mild hypothermia on energy metabolism and hydroxyl radical production as well as delayed neuronal death (DND) in hippocampus during cerebral ischemia/reperfusion in gerbils.METHODS: Forebrain ischemia was induced by occluding bilateral common carotid arteries with aneurysm clamps for 10 min in gerbils. The DND in hippocampal CA1 sector was assessed by histological examination, and hydroxyl radical, ATP (adenosine triphosphate), ADP (adenosine diphosphate),AMP (adenosine monophosphate) levels were determined by high performance liquid chromatography with electrochemical or ultraviolet detection. RESULTS: The number of survival neuronal in hippocampal CA1 sector in mild hypothermia + I/R group was more than that in I/R group after ischemia/reperfusion 96 h. The content of 2,3-DHBA (2,3- dihydroxybenzoic acid) in hippocampus in I/R group was much higher than those in sham operation and mild hypothermia + I/R group after reperfusion 6 h (P＜0.01), but there were no significant differences in 2,3-DHBA outputs among 3 groups 48 h and 96 h after reperfusion. There were no obvious differences in ATP, ADP, AMP level in hippocampus among 3 groups 6 h after reperfusion. However, the content of ATP,ADP,AMP in mild hypothermia + I/R group was much higher than those in I/R group 48 and 96 h after reperfusion (P＜0.01).CONCLUSION: Mild hypothermia can reduced DND by improving the cerebral energy metabolism during forebrain ischemia/reperfusion in gerbils.     

Changes and significance of ATPase and free radical in aged rats with brain ischemia-reperfusion

AIM: To study the mechanism of brain ischemia-reperfusion injury from ATPase activity and free radical metabolism in aged rats. METHODS: The young rats (5 months) and the aged rats (more than 20 months) were divided into young control group(YCG), young model group(YMG), aged control group(ACG) and aged model group(AMG). The ATPase and SOD activities and the contents of MDA, Ca^2＋, Na^＋ and K^＋ were measured in the rats with 30 min brain ischemia followed by 60 min reperfusion. RESULTS: The Ca^2＋content in the AMG was higher than that in the YMG and the ACG. The Na^＋-K^＋-ATPase activity in the ACG was lower than that in the YCG,was lower in the AMG than that in the YMG. The Ca^2＋-ATPase activities in the YCG was higher than that in the ACG, was lower in the AMG than that in the YMG and was higher than the ACG's. The serum and brain tissue SOD activities in the ACG was lower than that in the YCG, was lower in the AMG than YMG 's. The serum and brain tissue MDA/SOD ratio in the AMG was higher than that in the ACG.CONCLUSION:The brain tissue ischemia-reperfusion injury was related with calcium overload and free radical injury.The pathological changes were obvious and had some characteristics in the aged rats compared with the young rats because of the brain t issue aging changes in ATPase,calcium content and free radical metabolism in the aged rats.     

Role of glycine receptor in protection of glycine against anoxia/reoxygenation injury in cardiomyocytes

AIM:To investigate whether glycine receptor is involved in the protection of glycine against anoxia/reoxygenation injury in cardiomyocytes by detecting oxygen free radical metabolism, apoptosis and intracellular calcium overload. METHODS:The neonatal rat cardiomyocytes were cultured and exposed to anoxia and reoxygenation (A/R) in the presence of glycine receptor antagonist, glycine or in free chloride buffer. The superoxide dismutase (SOD) activity, the contents of malondialdehyde (MDA) and nitric oxide (NO), the intracellular free calcium concentration and the apoptotic rate in the cardiomyocytes were determined. RESULTS:SOD activity and NO content in cardiomyocytes were lower, but MDA content, intracellular free calcium concentration and apoptotic rate in cardiomyocytes were higher in A/R group than those in control. Pretreatment with glycine inhibited the above changes caused by A/R, which was reversed by strychnine treatment and in the free chloride medium. CONCLUSIONS:Glycine inhibits free radical production, attenuates calcium overload, decreases apoptotic rate and increases SOD activity and NO release in cardiomyocytes exposed to A/R. These findings suggest that glycine exerts a protective effect against A/R injury via glycine receptor and glycine protects the neonatal rat cardiomycytes from A/R-induced injury in a chloride-dependent manner.     

Effects of cyclosporin on oxidative stress and mitochondrial energy metabolism in rat hippocampus after status epilepticus

AIM：To investigate the effects of cyclosporin on oxidative stress and mitochondrial energy metabolism in the rat hippocampus after status epilepticus. METHODS：Status epilepticus was induced by pilocarpine. The changes of malondialdehyde and superoxide dismutase in the rat hippocampus with or without cyclosporin injection were evaluated. Additionally, the mitochondrial permeability transition, the activity of mitochondrial respiratory chain complex I/III and ATP content in the rat hippocampus were detected. RESULTS：Cyclosporin significantly inhibited mitochondrial permeability transition in the rat hippocampus after status epilepticus. Decreased malondialdehyde and increased superoxide dismutase levels were detected in cyclosporin treatment group compared with status epilepticus group (P<0.05). More-over, the activity of mitochondria respiratory chain complex I, not III, in the mitochondrial fraction increased after cyclo-sporin treatment (P<0.05). In addition, cyclosporin significantly prevented the decrease of ATP content in rat hippocampus after status epilepticus (P<0.05). CONCLUSION：Cyclosporin suppresses oxidative stress in the rat hippocampus after status epilepticus. Cyclosporin alleviates the impairment of mitochondrial energy metabolism in rat hippocampus after status epilepticus.     

茶多酚和咖啡因对缓解葡萄铝毒的生理机制

以葡萄苗为试材,采用无土栽培的方法,研究了在10mmol·L~(-1)硫酸铝钾胁迫下,0.25、0.50、0.75、1.00mg·L~(-1)的茶多酚和咖啡因处理对缓解葡萄铝毒的生理效应,以期为葡萄的耐铝栽培提供参考依据。结果表明:铝胁迫下葡萄生物量、叶绿素含量、根系活力下降,根冠比上升;叶片蛋白质、脯氨酸和过氧化氢的含量及过氧化物酶(POD)、超氧化物歧化酶(SOD)的活性上升;叶片和根系的丙二醛含量和氧自由基产生速率也上升。但在加入茶多酚和咖啡因后,葡萄生物量、叶绿素含量、根系活力、叶片POD和SOD活性,以及叶片、根系蛋白质和脯氨酸的含量均高于铝胁迫处理;而根冠比、叶片和根系的氧自由基产生速率、过氧化氢和丙二醛的含量则低于铝胁迫处理。茶多酚和咖啡因处理能够降低铝胁迫对葡萄植株生长的抑制作用,缓解铝毒对葡萄的伤害,效果最显著的是0.75mg·L~(-1)茶多酚和0.50mg·L~(-1)咖啡因处理。     

Exogenous putrescine reduces flooding-induced oxidative damage by increasing the antioxidant properties of Welsh onion

Soil flooding is an environmental factor of seasonal occurrence that negatively affects plant performance. Polyamines play an important role in the plant response to adverse environmental conditions including flooding stress. The objective of the present study was to assess the comparative oxidative damage to Welsh onion plants caused by flooding stress and to examine the role of putrescine (Put) in this response. Welsh onion plants were treated with Put prior to 10 d flooding. A positive effect was observed when treating with 2 mM Put. Exogenous application of Put resulted in alleviation of flooding-induced reduced relative water content, plant growth and chlorophyll fluorescence. Superoxide radical (O₂⁻) and hydrogen peroxide (H₂O₂) contents were also reduced in stressed plants after Put pre-treatment and thereby the oxidative stress in plant cells was lowered. The antioxidant system, as an important component of the waterlogging-stress-protective mechanism including α,α-diphenyl-β-picrylhydrazyl (DPPH)-radical scavenging activity, superoxide anion radical scavenging, metal chelating activities and reducing power, can be upgraded by Put, which is therefore able to moderate the radical scavenging system and to lessen oxidative stress. Under non-flooding conditions, the anti-oxidative activity of Welsh onion was regulated and elevated by Put pre-treatment. These results suggest that Put confers flooding tolerance to Welsh onion, probably through inducing the activities of various anti-oxidative systems. Thus, exogenous 2 mM per plant of Put 24 h prior to flooding could alleviate flooding stress.     

COX-2 inhibitor protects rat heart against oxidative stress through a pathway independent of cyclooxygenase

AIM: To investigate whether nimesulide ［a selective cyclooxygenase 2 (COX-2) inhibitor］ and piroxicam (an inhibitor of COX-1) protect the rat hearts against oxidative stress induced by hydrogen peroxide,superoxide anion or hydroxyl free radical.METHODS: Cardiac contractility,lactate dehydrogenase (LDH) and malondialdehyde (MDA) were analyzed by the Langendorff method in isolated rat hearts.Production of 6-Keto-PGF1α,a marker of COX activity,was measured in isolated rat hearts.RESULTS: Rat hearts were exposed to hydrogen peroxide (H₂O₂),pyrogallol (which produced superoxide anion) or Vit C+Fe2+ (which produced hydroxyl free radical) for 10 min followed by reperfusion for 30 min.H₂O₂ decreased cardiac contractility and increased LDH release,which was inhibited by nimesulide (3 mg/kg) ［LVDP 72%±10% vs 61%±11%,LDH （5.5±2.5）U/L vs （8.0±2.1）U/L,P<0.05］.Piroxicam (3 mg/kg) increased systolic function (LVDP 73%±10% vs 61%±11%,P<0.05),but exacerbated diastolic function ［LVEDP （29.00±5.61）mmHg vs （23.16±3.57） mmHg,P<0.01］ in H₂O₂ treated rat hearts.Nimesulide also protected rat hearts against superoxide anion and hydroxyl free radical injury.Nimesulide and piroxicam had no effect on the content of 6-Keto-PGF_1α in rat hearts.Mitochondrial ATP sensitive potassium channel (mitoK_ATP) inhibitor 5-HD blocked the improvement of contractility (LVDP and ±dp/dt_max) induced by nimesulide in H₂O₂ treated rat hearts (53%±12% vs 69%±3%,58%±11% vs 72%±7% and 37%±8% vs 51%±4% respectively,P<0.01).CONCLUSION: The results suggests that COX-2 inhibitor nimesulide can protect rat hearts against oxidative injury.The protection is independent of COX activity.Activation of mitoK_ATP may be involved in nimsulide-induced cardioprotection in rat hearts.     

Dependence of adrenoceptor regulation on oxidative stress in cardiac injury induced by high sympathetic activity in rats

AIM：To investigate the dependence of the adrenoceptor regulation on oxidative stress in the rats with cardiac injury induced by high sympathetic activity. METHODS：Healthy SD rats were randomly divided into 7 groups: control, model, propranolol (Pro), prazosin (Praz), Pro+Praz, vitamin E (VE) and Pro+Praz+VE. The rats were intraperitoneally injected with norepinephrine (NE) for continuous 16 d to reproduce cardiac injury, and treated with the respective drugs. During the experimental process, the body weight was recorded. At the end of the experiments, the following parameters were measured: the ventricular remodeling indexes (cardiac index and hydroxyproline of the left ventricle), histopathologic examination, oxidative/antioxidative indexes ［MDA, SOD, catalase (CAT), GSH-Px and total antioxidant capacity (T-AOC)］, and energy metabolism (Na+-K+ ATPase and Ca2+-Mg2+ATPase). RESULTS：The increase of body weight in model group was significantly slower than that in control group after 9 d of treatment (P<0.05). The cardiac index and left ventricular hypertrophy were significantly increased. Oxidation/antioxidation and energy metabolism were disturbed. In Pro, Praz, Pro+Praz and VE groups, the body weight, cardiac index, left ventricular fibrosis and oxidative/antioxidative dysfunction were ameliorated. Pro, Praz and Pro+Praz increased the activity of Na+-K+ ATPase and Ca2+-Mg2+ATPase. Treatment with Pro+Praz showed the best result in all of the indexes (P<0.05). CONCLUSION：The dependence of adrenoceptor regulation plays an important role in the formation of oxidative stress in the process of rat cardiac injury induced by high sympathetic activity.