川芎嗪对缺血再灌注损伤心肌重要呼吸酶的影响

目的:观察川芎嗪对大鼠缺血再灌注损伤心肌线粒体中琥珀酸脱氢酶(SDH)和细胞色素氧化酶(CCO)的影响及可能机制。方法:结扎冠状动脉30 min后再灌20 min,复制缺血再灌注模型。测定心肌线粒体中SDH、CCO、SOD和GSH·PX活力及MDA和细胞色素含量。结果:缺血再灌组(IR)SDH和CCO活力显著低于假手术对照组;缺血再灌加川芎嗪组(IR+L)的SDH和CCO活力显著高于缺血再灌组(P＜0.01),MDA含量明显降低,SOD及GSH·PX活力也明显升高。结论:川芎嗪对缺血再灌注损伤心肌中SDH和CCO活力降低有显著的拮抗作用,其机理可能是通过提高对氧自由基的清除及抑制脂质过氧化     

大鼠非梗塞区心肌线粒体呼吸酶活性的动态变化及睾酮的影响

观察了心肌梗塞(MI)雄鼠非梗塞区心肌线粒体呼吸酶:细胞色素C氧化酶(CCO)和琥珀酸脱氢酶(SDH)的动态变化及肌注睾酮的影响。结果:随梗塞时间的延长,线粒体CCO、SDH活性逐渐降低。到MI后9天,CCO及SDH活性分别明显低于自身1天组,而睾酮MI组(MIT)的SDH活性:3天组明显高于MI及正常对照组(NC),到MI后9天,又显著降低;CCO活性:1天组明显高于NC组,3天、9天组均明显低于NC及自身1天组。结果提示:心肌梗塞后,非梗塞区心肌线粒体CCO和SDH活性早期代偿性升高,之后均降低。短期应用睾酮可显著增加其活性,较长时间应用则明显抑制之。     

氧反常心肌线粒体呼吸功能变化及丹参酮Ⅱ_A磺酸钠的影响

健康雄性新西兰家兔28只,随机分为四组:正常对照组,缺氧组、氧反常组、DS-201氧反常组。离体心脏灌流造成心肌缺氧、氧反常模型。分离心肌线粒体,分光光度法测定线粒体内膜呼吸酶——琥珀酸脱氢酶(SDH)和细胞色素氧化酶(CCO)活力;氧电极法测定线粒体呼吸耗氧量,呼吸底物分别采用谷氨酸加苹果酸或琥珀酸。     

高脂血症小鼠脑缺血再灌注后脑组织线粒体功能降低

脑缺血再灌注(ischemia reperfusion,IR)损伤与细胞能量代谢障碍密切相关,细胞内线粒体酶是保证细胞产生ATP的重要因素。线粒体酶活性下降可直接干扰细胞呼吸链的电子传递,阻碍三羧酸循环的进程,影响细胞能量代谢。本实验观察了高脂血症小鼠脑IR后30 d内不同时期脑海马组织琥珀酸脱氢酶(SDH)和细胞色素氧化酶(CCO)活力以及线粒体ATP合成速率的变化,旨在探讨能量代谢障碍在脑IR损伤中所起的作用。1材料与方法1·1仪器和试剂:日本产UV-120-C2型分光光度计,美国产Waters-840型高效液相色谱仪。SDH、CCO活力测定试剂盒、ATP生成速…     

人参果皂甙对失血性休克犬心肌的保护作用

用杂种犬16只分为失血性休克组(HS)和失血性休克人参果皂甙组(HSG)。HS组动物由一侧颈总动脉放血至血压40mmHg(5.33kPa),放血后4h内采用放血和输血的方法维持血压。HSG组动物于放血前30min静脉注射人参果皂甙,HS组动物静脉注射等量的生理盐水,其它实验过程同HS组。两组动物存活时间,处死前血压和终失血量均存在显著性差异(P<0.005,P<0.05,P<0.001)。动物死亡后观察心肌细胞内某些酶的含量变化,HSG组动物心肌磷酸肌酸激酶(CK)、乳酸脱氢酶(LDH)、琥珀酸脱氢酶(SDH)和细胞色素氧化酶(CCO)的含量明显高于HS组。电镜观察:HS组动物心肌细胞的肌膜、核膜和线粒体均有不同程度的损伤,而HSG组动物心肌细胞的肌膜、核膜和线粒体基本正常。以上结果表明:人参果皂甙具有抗休克和保护心肌的作用。     

硫酸腺嘌呤预处理对大鼠缺血心脏的保护效应

本研究应用对大鼠注入腺苷前质一硫酸腺嘌呤预处理与经典的预处理方法对比发现，两种形式的预处理均可取得类似的心肌保护的预处理效应，表现为心肌超微结构的良好保存以及提高心肌SDH、CCO、Ca2 －Mg2 ATPase活性和降低心肌CK的漏出．     

硫化氢供体对阿霉素心肌病大鼠心肌结构及心功能的影响

目的探讨给予外源性硫化氢(H2S)供体硫氢化钠(NaHS)对阿霉素(ADR)心肌病大鼠心功能及心肌结构的影响及其作用机制。方法雄性Wistar大鼠54只,随机分5组(1)ADR组;(2)ADR 小剂量NaHS组;(3)ADR 大剂量NaHS组;(4)对照组;(5)NaHS组。药物均腹腔注射,连续用药10周,检测心功能和血流动力学指标,于光镜及电镜下观察显微及超微结构,并测定其血浆及心肌组织中H2S含量。结果阿霉素组大鼠心功能较对照组明显降低(P<0.01),心肌组织呈心肌病样改变,且血浆及心肌组织中H2S含量均明显低于对照组(P<0.001)。经补充外源性H2S供体NaHS后,大鼠心功能较前明显改善,心肌组织病理损害程度明显减轻。结论H2S参与了大鼠阿霉素心肌病的发病过程,补充外源性H2S可以改善阿霉素心肌病大鼠心功能,减轻心肌损伤。     

线粒体动力学在脓毒症心肌病中的研究进展

脓毒症心肌病为脓毒症的严重并发症之一,其确切病理机制尚不完全清楚.线粒体分裂-融合的动态过程称之为线粒体动力学,由一系列线粒体动力学相关蛋白调控.近年来,大量研究表明线粒体分裂-融合失衡可诱发各种心脏疾病,包括脓毒症心肌损害.目前对脓毒症心肌病尚无特异性治疗,心肌线粒体功能障碍与脓毒症心肌损害关系密切,调节线粒体动力学有望成为其干预的新靶点.     

骨髓间充质干细胞自体移植治疗阿霉素心肌病

目的:探讨骨髓间充质干细胞(MSCs)自体移植入兔阿霉素(ADR)心肌病心肌后的微环境依赖性分化及对心功能的影响。方法:日本大耳白兔随机分为:心肌病自体细胞移植组(n=10),心肌病对照组(n=8)及假手术组(n=6)。将自体MSCs和同体积的培养基分别移植入前两组动物心肌内,假手术组仅作开胸术而无移植。术后4周行心功能及组织学检测。结果:与假手术组相比,心肌病组的心功能明显降低;与心肌病对照组相比,自体移植组的心功能有显著改善,并在移植部位发现移植细胞有心肌肌钙蛋白T的表达。结论:MSCs移植入ADR心肌病的心肌组织中后,可在其微环境中存活并分化为心肌样细胞,并显著改善左室功能。     

脂肪因子chemerin对肥大的心肌细胞线粒体功能障碍的影响

目的:研究脂肪因子chemerin对肥大的大鼠心肌H9C2细胞线粒体的调节作用,探讨其对肥大的H9C2心肌细胞线粒体功能障碍的影响。方法:体外细胞实验分为正常组、chemerin组、血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)模型组和AngⅡ+chemerin组。采用免疫荧光染色方法和qPCR实验鉴定模型构建是否成功,电镜观察心肌细胞线粒体的形态变化,流式细胞术检测心肌H9C2细胞中线粒体膜电位和膜通透性,酶活性试剂盒检测细胞色素C氧化酶(cytochrome C oxidase,COX)和琥珀酸脱氢酶(succinate dehydrogenase,SDH)的活性。结果:与正常组比较,AngⅡ组和chemerin组H9C2细胞的线粒体结构损坏严重,线粒体膜通透性显著增加(P0. 01),线粒体膜电位及COX和SDH酶活性明显降低(P0. 01),且AngⅡ+chemerin组线粒体损伤更明显(P0. 05)。结论:脂肪因子chemerin刺激不仅可诱导心肌H9C2细胞肥大,还可促进肥大的心肌H9C2细胞线粒体功能障碍。     

Cytochrome c oxidase as the target of the heat shock protective effect in septic liver

Liver function failure is one of the characteristics of critically ill, septic patients and is associated with worse outcome. Our previous studies have demonstrated that heat-shock response protects cells and tissue from subsequent insults and improves survival during sepsis. In this study, we have shown that mitochondrial cytochrome c oxidase (CCO) is one of the major sources of that protective effect. Experimental sepsis was induced by the cecal ligation and puncture (CLP) method. Heat-shock treatment was induced in rats by hyperthermia 24 h before CLP operation. The results showed that ATP content of the liver declined significantly, and the enzymatic activity of mitochondrial CCO was apparently suppressed during the late stages of sepsis. The mitochondrial ultrastructure of septic liver showed the deformity, mild swelling and inner membrane budding. Heat-shock treatment led to heat-shock protein 72 overexpression and prevented the downregulation of Grp75 during sepsis. On the contrary, the expression of the enzyme complex and its activity were preserved, associated with the minimization of ultrastructural deformities. In conclusion, the maintenance of mitochondrial function, especially the CCO, may be an important strategy in therapeutic interventions of a septic liver.     

Ultrastructural and metabolic profiles on single muscle fibers of different types after hindlimb suspension in rats

The relationships between ultrastructural and metabolic profiles in different types of single muscle fiber after hindlimb suspension in rats were examined. Glycolytic (lactate dehydrogenase, LDH; phosphofructokinase, PFK) and oxidative (succinate dehydrogenase, SDH; malate dehydrogenase, MDH) enzyme activities in extensor digitorum longus (EDL) and soleus (SOL) muscles were measured. Relative mitochondrial and lipid droplet volumes were also measured in single muscle fiber of different types. Glycolytic enzyme activity in EDL muscle and oxidative enzyme activity in soleus muscle decreased following suspension for 2 weeks. LDH and PFK activities in fast-twitch (FG, fast-twitch glycolytic; FOG, fast-twitch oxidative glycolytic) fibers and oxidative enzymes in FOG and FG fibers decreased following suspension. Relative mitochondrial volume decreased significantly in all types (SO, slow-twitch oxidative; FOG, and FG) of fibers following suspension. The mitochondrial volume in SO fiber of the control group was significantly (p less than 0.01) higher than that of suspended group; however, SDH and MDH activities were not different between the control and suspended groups. The structural and metabolic changes following hindlimb suspension were influenced by different factors, respectively. Changes in ultrastructural and metabolic profiles in response to the hindlimb suspension differed according to the type of fibers.     

非创伤性预处理对大鼠缺血心脏的保护效应

目的 :探讨三种非创伤性预处理对大鼠缺血心脏的保护效应。方法 :采用 2 5 0g～ 3 0 0 gSD雄性大鼠 48只 ,分成 6组 ,即假手术组(Ⅰ组 )、缺血 /再灌组 (Ⅱ组 )、经典缺血预处理组 (Ⅲ组 ) ,缺氧预处理组 (Ⅳa组 )、后肢缺血预处理组 (Ⅳb组 )、去甲肾上腺素预处理组 (Ⅳc组 ) ,观察各组左室梗塞范围、心肌琥珀酸脱氢酶 (SDH )、Ca2 + Mg2 + ATPase、细胞色素氧化酶 (CCO)活性的变化。结果 :Ⅳa、Ⅳb、Ⅳc三组非创伤性预处理均可明显缩小左室梗塞范围、提高心肌SDH、Ca2 + Mg2 + ATPase、CCO酶活性。结论 :三种非创伤性预处理均能使大鼠显示和经典预处理相类似的心脏保护效应。     

Mitochondrial dysfunction and ultrastructural damage in the hippocampus of pilocarpine-induced epileptic rat

Mitochondrial dysfunction has been implicated as a contributing factor in epileptic seizures. Present studies were carried out to decipher seizure-dependent changes in mitochondrial function and ultrastructure in the chronic condition of temporal lobe epilepsy (TLE) induced by pilocarpine in rat hippocampus. Enzyme assay revealed significant depression of the activity of mitochondrial- and nuclear-encoded cytochrome oxidase (COX). Conversely, the activity of nuclear-encoded succinate dehydrogenase (SDH) remained unchanged. Discernible mitochondrial ultrastructural damage, varying from swelling to disruption of membrane, was observed in the hippocampus. Quantitative real-time PCR and Western blotting showed the expression of mitochondrial-encoded COX subunit III (COXIII) dropped significantly during the chronic seizure activity; the corresponding expression of COX subunit IV (COXIV) displayed no significant change. Most likely, our results suggest that dysfunction of mitochondrial COX respiratory enzyme and mitochondrial ultrastructural damage in the hippocampus are associated with prolonged seizure during experimental TLE and mitochondria are more vulnerable to epilepsy.     

糖尿病大鼠膈肌酶组织化学研究

目的:观察糖尿病早期膈肌酶组织化学变化,以了解糖尿病膈肌的损害。方法:应用酶组织化学方法观察糖尿病4周大鼠膈肌组织脱氢酶、水解酶和氧化酶活性变化。结果:糖尿病4周大鼠膈肌组织琥珀酸脱氢酶、苹果酸脱氢酶、异柠檬酸脱氢酶、谷氨酸脱氢酶、辅酶Ⅰ黄递酶、葡萄糖-6-磷酸脱氢酶、酸性磷酸酶和酸性-α-萘酸性酯酶活性强于对照组,乳酸脱氢酶和细胞色素氧化酶活性弱于对照组,辅酶Ⅱ黄递酶无明显改变,5'-核苷酸酶不着色。图像分析显示糖尿病大鼠膈肌组织琥珀酸脱氢酶、苹果酸脱氢酶、异柠檬酸脱氢酶、谷氨酸脱氢酶、辅酶Ⅰ黄递酶、葡萄糖-6-磷酸脱氢酶、酸性磷酸酶和酸性-α-萘酸性酯酶着色深度(A)明显高于对照组,而乳酸脱氢酶和细胞色素氧化酶明显低于对照组,辅酶Ⅱ黄递酶无明显差异。结论:糖尿病4周大鼠膈肌组织有氧氧化能力增强、糖酵解能力减弱、脂肪及能量代谢紊乱。     

Oxidative damage precedes nitrative damage in adriamycin-induced cardiac mitochondrial injury

The purpose of the present study was to determine if elevated reactive oxygen (ROS)/nitrogen species (RNS) reported to be present in adriamycin (ADR)-induced cardiotoxicity actually resulted in cardiomyocyte oxidative/nitrative damage, and to quantitatively determine the time course and subcellular localization of these postulated damage products using an in vivo approach. B6C3 mice were treated with a single dose of 20 mg/kg ADR. Ultrastructural damage and levels of 4-hydroxy-2-nonenal (4HNE)-protein adducts and 3-nitrotyrosine (3NT) were analyzed. Quantitative ultrastructural damage using computerized image techniques showed cardiomyocyte injury as early as 3 hours, with mitochondria being the most extensively and progressively injured subcellular organelle. Analysis of 4HNE protein adducts by immunogold electron microscopy showed appearance of 4HNE protein adducts in mitochondria as early as 3 hours, with a peak at 6 hours and subsequent decline at 24 hours. 3NT levels were significantly increased in all subcellular compartments at 6 hours and subsequently declined at 24 hours. Our data showed ADR induced 4HNE-protein adducts in mitochondria at the same time point as when mitochondrial injury initially appeared. These results document for the first time in vivo that mitochondrial oxidative damage precedes nitrative damage. The progressive nature of mitochondrial injury suggests that mitochondria, not other subcellular organelles, are the major site of intracellular injury.     

Effects of niclosamide on Oncomelania hupensis, the intermediate snail host of Schistosoma japonicum: an enzyme-histochemical study

An enzyme-histochemical study of five enzymes, namely succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), cytochrome oxidase (CCO), cholinesterase (CHE) and nitric oxide synthase (NOS), was elucidated in the soft tissues of Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum, before and after the treatment with a suspension concentrate of niclosamide (SCN). Following the treatment of SCN, a marked loss occurred in the activity of the five enzymes mentioned above. LDH and SDH showed their strongest activity in the buccal mass and muscular fibers, CCO in buccal mass and liver, CHE in pellicle and ganglia, and NOS in muscular fibers and pharyngeal canal. The results indicate that SCN impairs the activities of the enzymes influencing the transfer of neurotransmitter and energy supply in O. hupensis, ultimately leading to the loss of various physiological functions, which is considered to be a cause of death in O. hupensis.     

Age and exercise-related changes in myocardial mitochondria in mice

A quantitative histochemical and an ultrastructural study was performed on the left ventricular myocardium of C57BL/6J female mice to evaluate the effects of aging and running exercise on mitochondrial structure and SDH activity. A comparison was made between 6-month-old ("young") and 27-month-old ("old") sedentary mice with age-matched mice subjected to running schedules (10 or 30 min/d) for 6 weeks. In longer-term studies, 27-month-old mice were given similar daily running schedules over a 10 month period ("long term runners"). No significant differences were found in SDH activity during the normal course of aging in mice (6 to 27 months of age), however, the response to running differed markedly in young versus old mice. "Young" trained mice showed significant increase in SDH activity compared with age-matched sedentary mice, whereas "old" trained mice showed significantly reduced SDH activity. Electron microscopy showed ultrastructural changes in mitochondria associated with aging including the development of large aggregations of mitochondria in subsarcolemmal and paranuclear sites. Running schedules, especially in aged runners, caused an increase in interfibrillar mitochondria hypertrophy, loss of matrix and cristae, incorporation of lipid inclusions and the formation of giant mitochondria. These abnormal mitochondrial changes are interpreted as being degenerative and possibly contributing to the reduced SDH levels found in cardiac myocytes of aged runners. Our results indicate that whereas regular exercise in young animals enhanced SDH activity, in aged mice it may be detrimental rather than beneficial.