益心康含药血清对氧应激致大鼠心肌线粒体呼吸链酶损伤的保护作用

目的研究氧应激对大鼠心肌线粒体呼吸链酶活性的影响及中药复方益心康胶囊(H303)含药血清对损伤的保护作用。方法 利用氧应激损伤体系(Fe2+/VitC)与大鼠心肌线粒体共同孵育30min,观察对线粒体呼吸链酶-琥珀酸脱氢酶(SDH)和细胞色素氧化酶(CCO)的影响。结果 大鼠心肌线粒体氧应激后,可致SDH及CCO活性明显降低。H303含药血清可使损伤明显减轻,表现为明显增强上述两种酶的活性。结论 H303含药血清对氧应激造成的线粒体呼吸链关键酶活性的降低具有保护作用。     

五味子乙素对心肌缺血再灌注心肌细胞及线粒体损伤的影响

目的观察五味子乙素对心肌缺血再灌注心肌细胞及线粒体损伤的影响。方法采用H9c2大鼠心肌细胞株建立缺氧/复氧心肌细胞损伤模型及毒胡萝卜素内脂诱导的心肌细胞内质网应激模型,检测细胞活力,检测细胞超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)含量评价五味子乙素对不同模型心肌细胞氧化应激反应影响;检测ATP及线粒体复合物活性水平,评价五味子乙素对细胞线粒体能量供应水平影响;检测谷氨酸脱氢酶和细胞色素C及Caspase 3、Caspase 9表达,观察五味子乙素对线粒体完整性的影响。结果五味子乙素可有效抑制不同心肌细胞模型的氧化应激反应,并减少心肌细胞谷氨酸脱氢酶和细胞色素C及Caspase 3、Caspase 9水平,增加细胞ATP水平及呼吸链复合酶。结论五味子乙素对心脏缺血再灌注损伤及内质网应激反应导致的心肌细胞损伤具有明显保护作用,对不同模型导致的线粒体损伤具有保护作用。     

茜草对半乳糖致衰小鼠心肌线粒体能量代谢的影响

目的研究茜草对D-半乳糖致衰小鼠心肌线粒体能量代谢的影响。方法以D-半乳糖致衰小鼠为模型，观察茜草对心肌线粒体呼吸链酶复合体Ⅰ、Ⅰ Ⅲ、Ⅱ Ⅲ的活性以及丙二醛(MDA)含量的影响。结果茜草可提高衰老小鼠心肌线粒体呼吸链酶复合体Ⅰ、Ⅰ Ⅲ、Ⅱ Ⅲ的活性，并能降低老年组MDA的含量。结论茜草能减轻线粒体过氧化损伤，通过抑制线粒体的脂质过氧化和改善呼嘤链酶的活性达到延缓衰老的目的。     

茜草多糖对半乳糖致衰老小鼠心肌线粒体能量代谢影响的研究

目的　研究茜草多糖对半乳糖致衰老小鼠心肌线粒体能量代谢的影响。方法　以D 半乳糖致衰老模型小鼠 ,观察茜草多糖对心肌线粒体呼吸链酶复合体Ⅰ、Ⅰ Ⅲ、Ⅱ Ⅲ的活性 ,H ATP酶的活性 ,Mn2 超氧化物歧化酶 (Mn2 SOD)活性以及丙二醛 (MDA)含量的影响。结果　茜草多糖可提高衰老小鼠心肌线粒体呼吸链酶复合体Ⅰ、Ⅰ Ⅲ、Ⅱ Ⅲ、H ATP酶及Mn2 SOD的活性 ,并能降低老年组MDA含量。结论　茜草多糖能减轻线粒体过氧化损伤 ,通过抑制线粒体的脂质过氧化和改善呼吸链酶的活性达到延缓衰老的作用。     

维生素E对大剂量维生素D3所致心肌损伤的保护作用

本实验以大剂量维生素Ｄ３作为条件因素建立动物心肌损伤模型，观察维生素Ｅ对心肌损伤的保护作用。结果，大剂量维生素Ｄ３能降低大鼠心肌呼吸酶（细胞色素氧化酶和琥珀酸脱氢酶）活性。明显降低血清维生素Ｅ含量，使大鼠血清、心肌、肝脏组织谷胱甘肽过氧化物酶（ＧＳＨ—Ｐｘ）活性降低，脂质过氧化物（ＭＤＡ）含量升高。而预先给维生素Ｅ，能明显提高大鼠血清维生素Ｅ含量，提高呼吸酶活性．增强大鼠血清。心肌、肝脏组织ＧＳＨ—Ｐｘ活性，降低脂质过氧化物值。使大鼠心肌坏死面积明显减少。     

再灌注致大鼠心肌线粒体损伤及益心康胶囊的保护作用

目的　观察再灌注对心肌线粒体的损伤 ,评价中药复方———益心康胶囊 (H30 3)的保护作用。方法　利用离体大鼠全心停灌 /再灌 (I/R)模型 ,测定心肌线粒体结构和功能的变化。结果　I/R可致线粒体结构和功能损伤 ,H30 3预先灌注给药可明显减轻心肌脂质过氧化程度 ,抑制磷脂酶A2 活性 ,抑制线粒体磷脂降解和游离脂肪酸生成 ,改善线粒体膜脂流动性。此外对呼吸功能及Ca2 + ATPase活性也具有明显的保护作用。结论　H30 3对再灌注所致的线粒体的损伤具有明显的保护作用     

硒对大鼠心肌,肾脏和骨骼肌线粒体膜保护作用机制的研究

硒是人和哺乳动物必需的微量元素,是谷胱甘肽过氧化物酶(GPx)的重要成分,参与清除体内的H_2O_2和有机过氧化物,在抗脂质过氧化、保护生物膜正常结构与功能方面有重要作用。大量研究表明,缺硒动物心肌、肝脏和肾脏等组织线粒体膜结构和功能异常,一般认为上述异常改变是缺硒导致体内重要含硒的抗氧化酶—GPx活性下降,机体抗氧化能力减弱和脂质过氧化增强的结果。但是细胞过氧化损害发生与否及损害程度除了与细胞抗氧化能力有关外,还与自由基生成有关,取决于二者间的平衡。目前,有关低硒时线粒体内膜呼吸链O_2生成有何变化尚不清楚。本文观察缺硒大鼠心肌、     

过量锰对病区粮饲养大鼠心肌损伤作用的实验研究

大白鼠喂饲克山病区粮和非病区粮,并分别加 1000ppm 锰。实验分4组,A 组非病区粮,B 组病区粮,C 组非病区粮 锰,D 组病区粮 锰,喂8周后处死。结果表明,B 和 D 组大鼠全血、心肌和肝脏的 GSH—Px 活性均明显下降,心肌、肝脏和血清脂质过氧化物含量升高,该两组间比较无明显差异。而 C 组大鼠的 GSH—Px 活性和脂质过氧化物含量与 A 组比较也无明显差异,提示过量锰(1000ppm)对动物体的 GSH—Px 活性和脂质过氧化物水平无明显影响。加锰组(C 和 D)大鼠心肌的线粒体肿胀和空泡变明显,电镜细胞化学显示心肌线粒体的细胞色素氧化酶和琥珀酸脱氢酶活性降低,D 组降低更明显、提示过量锰引起心肌损伤的主要环节可能是损害线粒体的功能与结构。并使喂饲病区粮大鼠心肌损害加重。     

菟丝子水提物对衰老模型大鼠心肌线粒体呼吸链酶复合体活性的影响

目的 探讨菟丝子水提物对大鼠心肌线粒体呼吸链酶复合体活性的影响.方法 将Wistar大鼠30只,随机分为青年对照组,衰老模型组,模型给药组,制作D-半乳糖衰老模型,模型给药组同时灌服菟丝子水提物.观察各组大鼠心肌线粒体丙二醛(MDA)的含量、超氧化物歧化酶(SOD)的活性以及呼吸链酶复合体Ⅰ、Ⅳ活性的变化.结果 菟丝子水提物可提高心肌线粒体SOD的活性、降低MDA的含量;并且使呼吸链酶复合体Ⅰ、Ⅳ活性明显升高.结论 菟丝子水提物能提高心肌线粒体抗氧化能力,改善线粒体能量代谢障碍,维护线粒体功能.     

阿托伐他汀对高胆固醇兔心肌线粒体能量代谢的影响

目的 探讨阿托伐他汀对高胆固醇血症兔心肌能量代谢的干预作用.方法 24只健康雄性新西兰兔随机分成正常对照组、高胆固醇组和阿托伐他汀组(予高胆固醇饮食并给与阿托伐他汀处理).喂养6周后,经兔耳缘静脉取空腹血标本测血清总胆固醇的浓度;取心肌组织,电镜观察心肌及线粒体超微结构改变;用高效液相色谱法测心肌线粒体ATP和辅酶Q10含量;用紫外分光光度法测线粒体呼吸链复合物Ⅱ、Ⅳ的活性.结果 高胆固醇组心肌纤维排列紊乱,部分断裂、溶解,线粒体肿胀,嵴紊乱、模糊,与正常对照组比较,线粒体呼吸链复合物Ⅱ、Ⅳ活性下降,线粒体ATP、辅酶Q10含量减少(P＜0.01);阿托伐他汀组与高胆固醇组比较,呼吸链复合物Ⅱ、Ⅳ活性升高(P＜0.01),线粒体ATP、辅酶Q10含量差异无统计学意义(P＞0.05).结论 阿托伐他汀可减轻高胆固醇血症导致的心肌及线粒体结构损伤,升高线粒体内膜呼吸链复合物Ⅱ、Ⅳ活性,进而改善线粒体氧化磷酸化能力.     

Melatonin administration prevents cardiac and diaphragmatic mitochondrial oxidative damage in senescence-accelerated mice

Cardiac and diaphragmatic mitochondria from male SAMP8 (senescent) and SAMR1 (resistant) mice of 5 or 10 months of age were studied. Levels of lipid peroxidation (LPO), glutathione (GSH), GSH disulfide (GSSG), and GSH peroxidase and GSH reductase (GRd) activities were measured. In addition, the effect of chronic treatment with the antioxidant melatonin from 1 to 10 months of age was evaluated. Cardiac and diaphragmatic mitochondria show an age-dependent increase in LPO levels and a reduction in GSH:GSSG ratios. Chronic treatment with melatonin counteracted the age-dependent LPO increase and GSH:GSSG ratio reduction in these mitochondria. Melatonin also increased GRd activity, an effect that may account for the maintenance of the mitochondrial GSH pool. Total mitochondrial content of GSH increased after melatonin treatment. In general, the effects of age and melatonin treatment were similar in senescence-resistant mice (SAMR1) and SAMP8 cardiac and diaphragmatic mitochondria, suggesting that these mice strains display similar mitochondrial oxidative damage at the age of 10 months. The results also support the efficacy of long-term melatonin treatment in preventing the age-dependent mitochondrial oxidative stress.     

车前子多糖对大鼠肝线粒体自由基防御功能的影响

目的探讨车前子多糖(PSP)对大鼠肝线粒体自由基防御功能的影响。方法差速离心法提取雄性SD大鼠肝线粒体,采用硫酸亚铁-维生素C(Fe2+-Vit C)激发剂,建立大鼠肝线粒体脂质过氧化(LPO)模型,比色法测定丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)和抗氧化物酶(T-AOC)活性,观察PSP对各生化指标的影响。结果 PSP浓度在25、50和100 mg/L范围时,MDA含量分别为3.94±0.15,3.65±0.18和2.88±0.20,均显著低于模型组6.47±0.48(P<0.01),表明PSP对肝线粒体脂质过氧化有抑制作用,而对抗氧化物酶类活性均有激活作用,与模型组比较,均明显升高(P<0.01)。结论 PSP对大鼠肝线粒体自由基的防御功能可产生一定的影响,对治未病起到一定的防治作用。     

Incorporation of marine lipids into mitochondrial membranes increases susceptibility to damage by calcium and reactive oxygen species: evidence for enhanced activation of phospholipase A2 in mitochondria enriched with n-3 fatty acids.

Experiments were designed to evaluate the susceptibility of mitochondrial membranes enriched with n-3 fatty acids to damage by Ca2+ and reactive oxygen species. Fatty acid content and respiratory function were assessed in renal cortical mitochondria isolated from fish-oil- and beef-tallow-fed rats. Dietary fish oils were readily incorporated into mitochondrial membranes. After exposure to Ca2+ and reactive oxygen species, mitochondria enriched in n-3 fatty acids, and using pyruvate and malate as substrates, had significantly greater changes in state 3 and uncoupled respirations, when compared with mitochondria from rats fed beef tallow. Mitochondrial site 1 (NADH coenzyme Q reductase) activity was reduced to 45 and 85% of control values in fish-oil- and beef-tallow-fed groups, respectively. Exposure to Ca2+ and reactive oxygen species enhance the release of polyunsaturated fatty acids enriched at the sn-2 position of phospholipids from mitochondria of fish-oil-fed rats when compared with similarly treated mitochondria of beef-tallow-fed rats. This release of fatty acids was partially inhibited by dibucaine, the phospholipase A2 inhibitor, which we have previously shown to protect mitochondria against damage associated with Ca2+ and reactive oxygen species. The results indicate that phospholipase A2 is activated in mitochondria exposed to Ca2+ and reactive oxygen species and is responsible, at least in part, for the impairment of respiratory function. Phospholipase A2 activity and mitochondrial damage are enhanced when mitochondrial membranes are enriched with n-3 fatty acids.     

Decrease in mitochondrial complex I activity in ischemic/reperfused rat heart: involvement of reactive oxygen species and cardiolipin

Reactive oxygen species (ROS) are considered an important factor in ischemia/reperfusion injury to cardiac myocytes. Mitochondrial respiration is an important source of ROS production and hence a potential contributor to cardiac reperfusion injury. In this study, we have examined the effect of ischemia and ischemia followed by reperfusion of rat hearts on various parameters related to mitochondrial function, such as complex I activity, oxygen consumption, ROS production, and cardiolipin content. The activity of complex I was reduced by 25% and 48% in mitochondria isolated from ischemic and reperfused rat heart, respectively, compared with the controls. These changes in complex I activity were associated with parallel changes in state 3 respiration. The capacity of mitochondria to produce H2O2 increased on reperfusion. The mitochondrial content of cardiolipin, which is required for optimal activity of complex I, decreased by 28% and 50% as function of ischemia and reperfusion, respectively. The lower complex I activity in mitochondria from reperfused rat heart could be completely restored to the level of normal heart by exogenous added cardiolipin. This effect of cardiolipin could not be replaced by other phospholipids nor by peroxidized cardiolipin. It is proposed that the defect in complex I activity in ischemic/reperfused rat heart could be ascribed to a ROS-induced cardiolipin damage. These findings may provide an explanation for some of the factors responsible for myocardial reperfusion injury.     

Lipid peroxidation levels in rat cardiac muscle are affected by age and thyroid status

Free radicals, hydroxyperoxides and H(2)O(2) are all known to damage cell components. This study was designed to compare the concentrations of hydroxyperoxide and free radical scavengers in the cardiac muscles of old rats in the hyper- or hypothyroid condition, to determine whether rates of peroxidation would differ with age, thyroid status, or both. Rats were rendered hyper- or hypothyroid by administration of l-thyroxine or methimazole for 4 weeks. Among the old rats, the lipid peroxide (LPO) concentrations, measured as thiobarbituric acid (TBA) reactants, were significantly greater in the hyperthyroid than in the euthyroid state and the LPO concentrations measured as TBA+Fe(3+) reactants, which may be precursors of LPO, were significantly greater in the hyperthyroid state, whereas in young rats, the LPO concentrations measured by TBA or TBA+Fe(3+) methods did not differ significantly in the hyperthyroid state. In the euthyroid state, the concentration of LPO measured as TBA+Fe(3+) reactants was significantly reduced with age. Xanthine oxidase (XOD) activity also was markedly increased with age, being more pronounced in the hyperthyroid than in the euthyroid state. The Mn and Cu/Zn superoxide dismutase activities were greater in the hyperthyroid than in the euthyroid state. Glutathione peroxidase activity decreased with age in the euthyroid and, particularly, in the hyperthyroid state. Catalase activity was not affected in the old rats. Concentrations of alpha-tocopherol in the old rats were high in the hyperthyroid state and low in the hypothyroid state, whereas the levels of beta- and gamma-tocopherols in these rats were unchanged in both conditions as compared with the euthyroid state findings. Data suggest that the site of free radical generation differs in older rats, with additional shifts in the location of intracellular lipid peroxidation being noted during hyperthyroidism. Thus, as rats age, the reduction of the free radical scavenger system and the increase in LPO and XOD activities might induce myocardial dysfunction.     

Effects of rosiglitazone on the liver histology and mitochondrial function in ob/ob mice

Insulin resistance is present in almost all patients with nonalcoholic steatohepatitis (NAFLD), and mitochondrial dysfunction likely plays a critical role in the progression of fatty liver into nonalcoholic steatohepatitis. Rosiglitazone, a selective ligand of peroxisome proliferator-activated receptor gamma (PPARgamma), is an insulin sensitizer drug that has been used in a number of insulin-resistant conditions, including NAFLD. The aim of this study was to analyze the effects of rosiglitazone on the liver histology and mitochondrial function in a model of NAFLD. All studies were carried out in wild-type and leptin-deficient (ob/ob) C57BL/6J mice. Ob/ob mice were treated with 1 mg/kg/day, and activity of mitochondrial respiratory chain (MRC), beta-oxidation, lipid peroxidation, glutathione content in mitochondria, and 3-tyrosine-nitrated proteins in mitochondria were measured. In addition, histological and ultrastructural changes induced by rosiglitazone were also noted. Rosiglitazone treatment increased liver steatosis, particularly microvesicular steatosis. In these animals, mitochondria were markedly swollen with cristae peripherally placed. In ob/ob mice, this drug increased PPARgamma protein expression and lipid peroxide content in liver tissue and decreased glutathione concentration in mitochondria. Rosiglitazone suppressed the activity of complex I of the MRC in ob/ob mice, but did not affect beta-oxidation. 3-Tyrosine nitrated mitochondrial proteins, significantly increased in ob/ob mice, were not modified by rosiglitazone treatment. CONCLUSION: Treatment of ob/ob mice with rosiglitazone did not reverse histological lesions of NAFLD or improve MRC activity. On the contrary, rosiglitazone reduced activity of complex I and increased oxidative stress and liver steatosis.     

复方血栓通胶囊对心肌缺血犬血流动力学的影响

目的:探讨复方血栓通胶囊对心肌缺血犬血流动力学的影响。方法:２５ 只健康杂种犬随机分为５ 组:对照组、缺血组、地奥心血康组、高剂量和中剂量血栓通组,采用结扎冠状动脉前降支的方法建立犬急性心肌缺血的动物模型,用四道生理记录仪记录犬心脏舒缩期左室内压变化速率（＋ ｄｐ／ｄｔｍ ａｘ ,－ ｄｐ／ｄｔｍ ａｘ ）和血压的动态变化,并测定心肌缺血后不同时间血中超氧化物歧化酶（ Ｓ Ｏ Ｄ）的活性和丙二醛（ Ｍ Ｄ Ａ）的含量。结果:用药组犬在心肌缺血后,其＋ ｄｐ／ｄｔｍ ａｘ 和－ ｄｐ／ｄｔｍ ａｘ 下降幅度小于缺血组（ Ｐ＜ ０．０５）,而且收缩压与舒张压的下降幅度也小于缺血组（ Ｐ＜０．０５）,血栓通与地奥心血康组及对照组无显著性差异（ Ｐ＞ ０．０５）。用药组血浆 Ｓ Ｏ Ｄ活性高于缺血组, Ｍ Ｄ Ａ 含量低于缺血组,而用药组之间则无显著性差异。结论:血栓通胶囊具有改善心脏功能,升高血压的功效;这可能与提高心肌缺血犬的 Ｓ Ｏ Ｄ 活性,抑制脂质过氧化,清除自由基的作用有关。     

重症急性胰腺炎NF-κB活化及维生素C干预治疗的实验研究

目的观察重症急性胰腺炎胰腺组织中NF-kB活化情况及VitC干预治疗对NF-kB活性的影响。方法54只雌性大鼠随机分为假手术组、重症急性胰腺炎组(SAP)、VitC预处理组(VitC SAP)。SAP模型经胆胰管内加压注射3.5%牛黄胆酸钠0.1ml／100g。VitC预处理组在建立模型前1h按VitC注射液1g／kg肌注给药。分别于建模后3h、6h、12h将大鼠分批处死,检测血淀粉酶,免疫组化法检测各组胰腺组织NF-kB的表达。常规病理并按Jan'S标准进行评分。结果VitC预处理组血清淀粉酶水平较SAP组在各个时间点均明显下降(3h,P<0.01,6h、12h,P<0.05)。VitC预处理组胰腺炎症范围、腺泡坏死程度及血管变化均较SAP组明显减轻,胰腺组织病理评分在各时间点明显低于SAP组(P<0.01或P<0.05)。假手术组可见胰腺组织NF-kB少量表达,VitC预处理组胰腺细胞NF-kB阳性率在各时间点均较SAP组明显减少(P<0.01或P<0.05)。结论抗氧化剂VitC能抑制胰腺细胞NF-kB活化,减轻SAP胰腺组织损害和降低血清淀粉酶水平,对SAP具有一定治疗作用。