五味子酚对氧自由基引起大鼠脑突触体和线粒体损伤的保护作用

以Fe²⁺-半胱氨酸(Cys)为氧自由基生成系统,在体外模仿脑出血或脑外伤引起的氧自由基损伤的模型,观察五味子酚是否对Fe²⁺-Cys引起的大鼠脑突触体和线粒体损伤有保护作用,以探讨Sal用于延缓衰老、防治某些神经系统疾病的可能性。结果显示,与Fe²⁺-Cys共温孵可使脑突触体和线粒体MDA生成量显著增加,线粒体ATPase活性下降。而预先加入Sal(10^{-6mol·L-1)可抑制MDA生成,防止线粒体ATPase活性降低。Sal对Fe2+-Cys引起的线粒体肿胀和膜流动性降低也有明显的保护作用,并能防止Fe2+-Cys所致线粒体和突触体形态的病理性损伤。结果提示,Sal对氧自由基引起的大鼠脑突触体和线粒体损伤有明显保护作用。}     

硫酸酯化虎奶多糖的制备及其抗氧化作用研究

目的对虎奶多糖进行硫酸酯化修饰 ,并研究其抗氧化活性。方法用氯磺酸 吡啶法对虎奶多糖进行硫酸酯化修饰得到硫酸酯化虎奶多糖 (S HNP) ;以Fe2 + Vc为氧自由基生成系统 ,体外观察S HNP对·OH引起的大鼠肝线粒体脂质过氧化损伤的保护作用 ;用化学发光法研究化学模拟体系CuSO4 Phen Vc H2 O2 DNA中S HNP对DNA损伤的保护作用 ;连苯三酚自氧化法观察S HNP对O·- 2 的清除作用。结果S HNP能显著抑制·OH引起的线粒体脂质过氧化产物TBARS的生成、线粒体的肿胀及膜流动性的降低 ;对·OH导致的DNA损伤有一定保护作用 ;对O·-2 有直接清除作用。结论S HNP具有较强的抗氧化活性。     

丹酚酸A对大鼠脑突触体和线粒体氧应激损伤的体外保护作用

利用蔗糖梯度法分离大鼠脑突触体和线粒体，以Fe^2＋-半胱氨酸（Cys）为氧自由基生成系统造成大鼠脑突触体和线粒体氧应激损伤模型. 在体外Fe^2＋-Cys与脑突触体和线粒体共同温孵可使丙二醛(MDA)生成量显著增加，线粒体ATP酶活性下降. 预先加入丹酚酸 A(Sal A)可显著抑制MDA生成，恢复线粒体 ATP酶活性，防止线粒体肿胀和膜流动性的降低. 通过电镜照片可看到Fe^2＋-Cys引起的线粒体和突触体结构病理性改变，预先加入Sal A可减轻Fe^2＋-Cys造成的这一损伤. 此外，Sal A可阻抑H₂O₂引起的脑突触体GSH含量的降低. 由此可见，Sal A体外对氧应激引起的大鼠脑突触体和线粒体脂质过氧化损伤有明显的保护作用.     

Adriamycin-induced lipid peroxidation in mitochondria and microsomes

The effect of the anti-neoplastic agent adriamycin on the peroxidation of lipids from rat liver and heart mitochondria and rat liver microsomes was investigated. The extent of total lipid peroxidation was determined by assaying for malondialdehyde (MDA), while the degradation of unsaturated fatty acids was monitored using gas chromatography. For liver mitochondria and microsomes, the formation of MDA was dependent on the concentrations of adriamycin, Fe3+, and protein, as well as time. In the presence of 50 microM adriamycin and saturating amounts of NADH, 1.5 +/- 0.2 nmol MDA/mg protein/60 min was produced with liver mitochondria. Upon addition of 25 microM Fe3+, the amount of MDA generated was increased to 6.5 +/- 0.1 nmol/mg protein/60 min. Liver microsomes produced amounts which were approximately 2-fold higher under all conditions. No MDA formation could be detected in rat heart mitochondria. The addition of 50 microM chlorpromazine completely inhibited peroxidation, whereas 0.5 to 1.0 mM p-bromophenacyl bromide blocked MDA formation by 50%. Analysis of fatty acids by gas chromatography showed that there was about a 50% decrease in arachidonic and docosahexaenoic acids in liver mitochondria and microsomes, but no change in the fatty acid content of heart mitochondria when incubated with both 50 microM adriamycin and 25 microM Fe3+ for 1 hr. These results suggest that (1) therapeutic concentrations of adriamycin enhance the peroxidation of lipids in liver mitochondria and microsomes through an enzymatic mechanism, especially in the presence of Fe3+; and (2) toxicity of this drug may be related to the degradation of membrane lipids.     

五味子酚对氧自由基损伤小鼠脾淋巴细胞的保护作用

研究了五味子酚(Sal)对氧自由基损伤小鼠脾淋巴细胞的影响。体外实验结果表明,Sal在5×10^-6mol·L^-1时对Fe²⁺-VitC引起的脾淋巴细胞GSH含量降低有明显的抑制作用,且能阻抑Fe²⁺-Cys引起的MDA生成增加,改善细胞膜的流动性。用扫描电镜观察到Sal在5×10^-4mol·L^-1时可逆转Fe²⁺-VitC引起的脾淋巴细胞表面微绒毛皱折减少、细胞变形等病理改变。体内高氧分压应激损伤小鼠实验表明,igSal20mg·kg^-1×8d可逆转脾淋巴细胞SOD活性代偿性增高,并提高脾淋巴细胞内GSH含量。以上结果提示Sal对氧自由基损伤脾淋巴细胞有保护作用。     

Antioxidant action of propofol on liver microsomes, mitochondria and brain synaptosomes in the rat

2,6-Diisopropylphenol (propofol), a new intravenous anaesthetic, has a structure similar to that of butylated hydroxytoluene (BHT). Both compounds inhibit the production of malondialdehyde (MDA) in rat liver mitochondria and microsomes as well as in rat brain synaptosomes treated with lipid peroxidation inducers.     

Antioxidant Action of Propofol on Liver Microsomes,Mitochondria and Brain Synaptosomes in the Rat*

Abstract: 2,6-Diisopropylphenol (propofol), a new intravenous anaesthetic, has a structure similar to that of butylated hydroxytoluene (BHT). Both compounds inhibit the production of malondialdehyde (MDA) in rat liver mitochondria and microsomes as well as in rat brain synaptosomes treated with lipid peroxidation inducers.     

羟苯氨酮对离体鼠心停灌-复灌损伤的保护作用

目的研究羟苯氨酮对全心停灌-复灌损伤的影响。方法采用离体大鼠心脏停灌40 min-复灌30 min模型，从心脏功能、心肌能量代谢、抗氧化、线粒体钙超载及超微结构等方面观察药物作用。结果停灌前和复灌时给予羟苯氨酮(1~10 μmol·L^-1)明显增加复灌时心肌收缩力与冠脉流量，降低冠脉流出液的肌酸磷酸激酶(CPK)活性，对抗损伤所致的心肌三磷酸腺苷(ATP)与磷酸肌酸(PCr)含量降低，增强心肌抗氧化能力，对抗线粒体钙超载，使线粒体超微结构保持得比较完整。结论羟苯氨酮明显对抗停灌-复灌致心肌损伤，为该药保护再灌注损伤提出有力依据。     

Vitamin E and glutathione are required for preservation of microsomal glutathione S-transferase from oxidative stress in microsomes

Glutathione (GSH) inhibited lipid peroxidation induced by NADPH-BrCCl3 in vitamin E sufficient microsomes, but did not in phenobarbital (PB)-treated microsomes (containing about 60% of normal vitamin E) or in vitamin E-deficient microsomes (containing about 30% of normal vitamin E). There was a good correlation between the increased formation of CHCl3 from BrCCl3 in the presence of GSH under anaerobic conditions and the vitamin E level in the microsomes. A normal level of vitamin E in microsomes was thus very important for GSH-dependent inhibition of lipid peroxidation and for the efficient formation of CHCl3 from BrCCl3. Bromosulfophthalein (BSP) eliminated the effects of GSH on lipid peroxidation and CHCl3 formation. The apparent Km and Vmax of substrates for GSH S-transferase were changed by in vivo depletion of vitamin E in microsomes, and the Vmax/Km values were significantly reduced. The enzyme activity in microsomes was inactivated following the loss of vitamin E during in vitro lipid peroxidation, and GSH prevented the loss of vitamin E and protected the enzyme from attack by free radicals. GSH inhibited lipid peroxidation induced by NADPH-Fe2+ and the loss of GSH S-transferase activity during the peroxidation in PB-treated microsomes, but did not in the case of induction by NADPH-BrCCl3. A possible relation between the microsomal GSH S-transferase activity and defense by GSH against lipid peroxidation in microsomes is discussed.     

茜草对半乳糖致衰小鼠心肌线粒体细胞色素含量的影响

目的:研究茜草对D-半乳糖致衰小鼠心肌线粒体细胞色素含量的影响。方法:以D-半乳糖致裘小鼠为模型,观察茜草对心肌线粒体呼吸链细胞色素b、c、aa3和丙二醛(MDA)含量、Mn-超氧化物歧化酶(Mn-SOD)活性的影响。结果:茜草可提高衰老小鼠心肌线粒体呼吸链细胞色素b、c、aa3的含量和Mn-SOD的活性,并降低MDA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提高呼吸链细胞色素的含量达到延缓衰老的目的。     

Influences of Ginkgo biloba on cyclosporin A induced lipid peroxidation in human liver microsomes in comparison to vitamin E, glutathione and N-acetylcysteine

The in vitro effect of cyclosporin A (CsA) on lipid peroxidation in human liver microsomes was investigated, and efforts were made to prevent the resulting toxic effect of CsA. Microsomes were prepared from human liver resection material and incubated with CsA (0, 10, 30, 100, 300, 1000 micrograms/mL) for one hour (pH 7.4, 37 degrees, 95% O2, 5% CO2). Subsequently the resulting concentrations of malondialdehyde equivalents (MDA) were determined, a breakdown product of lipid peroxidation. Furthermore the duration of incubation was varied (0, 15, 30, 60, 90 min) using a CsA concentration of 300 micrograms/mL. CsA was shown to stimulate MDA-formation to up to 10-fold of the control value in both a time and concentration dependent manner. The dosage dependent experiment stated above was repeated, adding alpha-tocopherol (vitamin E, 1 mM), reduced glutathione (GSH, 1 mM), N-acetylcysteine (0.1, 0.3, 1, 3 mM), and Ginkgo biloba extract (Gbe, 15, 50, 150 micrograms/mL), respectively, to the medium of incubation. Vitamin E, a potent radical scavenger, proved to inhibit lipid peroxidation almost totally. Both GSH and N-acetylcysteine were also able to prevent lipid peroxidation, suggesting that the antioxidant effect of GSH might be caused by its thiol group and does not depend on the integrity of the whole molecule. Gbe inhibited CsA induced lipid peroxidation in a concentration dependent manner. This effect of Gbe was diminished yet not totally abolished when FeCl3 was added to the medium of incubation, whereas N-acetylcysteine even slightly enhanced CsA stimulated lipid peroxidation in the presence of iron. These results suggest that Gbe might be able to prevent radical mediated damage to human membranes caused by CsA.     

扇贝裙边糖胺聚糖对血管内皮细胞的抗氧化活性

目的：探讨扇贝裙边糖胺聚糖（SS-GAG）的抗氧化活性。方法：用体外培养的人脐静脉内皮细胞株，建立过氧化氢（H2O2）诱导的血管内皮细胞损伤模型，用硫代巴比妥酸反应物法测定血管内皮细胞内氧化损伤产物丙二醛（MDA）的含量，用黄嘌呤氧化酶法测定细胞内的超氧化物歧化酶（SOD）的活性。结果：SS-GAG可明显减少MDA的生成，对细胞内的SOD活性有明显增强的作用。结论：SSGAG通过拮抗H2O2对血管内皮细胞的过氧化损伤，发挥其抗氧化活性。     

Bromosulfophthalein abolishes glutathione-dependent protection against lipid peroxidation in rat liver mitochondria

The effect of bromosulfophthalein (BSP) on GSH-dependent protection against lipid peroxidation in rat liver mitochondria was examined. Mitochondrial lipid peroxidation induced by ascorbate-Fe2+ was prevented by GSH, and addition of BSP abolished the protective effect of GSH. The effect of BSP was apparently not due to causing disappearance of GSH from the reaction mixture by interacting directly with GSH. BSP strongly inhibited the mitochondrial GSH S-transferase activity rather than the GSH peroxidase activity. Ascorbate-Fe2+-induced lipid peroxidation in mitochondria without addition of GSH was also stimulated to some extent by BSP, and the stimulation seems likely to be due to abolition of the inhibitory effect of endogenous GSH. GSH could not be replaced as an inhibitor of lipid peroxidation by cysteine, beta-mercaptoethanol, or dithiothreitol. The inhibitory effect of GSH on lipid peroxidation was not observed in vitamin E-deficient mitochondria. No inhibitory effect of exogenous vitamin E was demonstrated either in vitamin E-deficient mitochondria or in vitamin E-sufficient mitochondria in the presence of BSP, whether GSH was added or not. These results indicate that a mitochondrial GSH-dependent factor which inhibits lipid peroxidation requires vitamin E to exert its function. It is suggested that mitochondrial GSH S-transferase(s) may be responsible for GSH-dependent inhibition of lipid peroxidation in mitochondria, probably by scavenging lipid radicals.     

双环醇对大鼠肾脏缺血-再灌注损伤的保护作用

目的观察双环醇对缺血-再灌注诱发肾损伤的保护作用.方法在大鼠肾动脉缺血-再灌注模型上观察双环醇对肾缺血-再灌注引起的血清丙二醛(MDA)、尿素氮(BUN),肾脏还原型谷胱甘肽(GSH)、谷胱甘肽巯基转移酶(GST)及肾线粒体膜流动性改变的影响.结果双环醇ig 50及200 mg*kg-1可剂量依赖性保护缺血-再灌注引起的血清MDA及BUN升高、肾GSH含量降低,同时可诱导GST活性,缓解由于缺血-再灌注损伤引起的线粒体膜流动性降低.结论双环醇对肾缺血-再灌注损伤有保护作用.     

Protective action of seven natural phenolic compounds against peroxidative damage to biomembranes.

The effects of seven phenolic compounds isolated from Salvia miltiorrhiza on peroxidative damage to liver microsomes, hepatocytes and erythrocytes of rats were studied. The results show that the seven compounds inhibited lipid peroxidation of rat liver microsomes induced by iron/cysteine and Vitamin C/NADPH. The hemolysis of rat erythrocytes induced by hydrogen peroxide was also inhibited. The degree of inhibition varied with different compounds. Among the seven compounds, the action of salvianolic acid A (Sai A) was the most potent. Therefore, the protective action of Sai A against peroxidative damage to isolated rat hepatocytes and their plasma membranes was evaluated further. Malondialdehyde (MDA) production and bleb of the surfaces of rat hepatocytes induced by iron/cysteine were prevented by Sai A. The production of MDA and the consumption of NADPH of the plasma membrane during lipid peroxidation initiated by iron/cysteine and Vitamin C/NADPH were also inhibited. The results strongly suggest that several phenolic compounds like Sai A have a protective action against peroxidative damage to biomembranes.     

灯盏花乙素对超氧阴离子引起的大鼠脑突触体氧化应激的保护作用

目的：研究灯盏花乙素对超氧阴离子引起的大鼠脑突触体氧化应激的保护作用．方法：采用与黄嘌呤(0．3mmol／L)和黄嘌呤氧化酶(0．02U)体系在37℃下孵育30min,建立大鼠脑突触体超氧阴离子氧化损伤模型．通过测定脂质过氧化产物丙二醛评价脂质过氧化程度．通过脂溶性荧光探针DPH的各向异性判断突触体膜的流动性．胞内钙离子的测定采用荧光光度法,以Fura2-AM为荧光探针．测定ATP酶解释放的无机磷确定Na~ ／K~ -ATP酶的活性．结果：超氧阴离子使大鼠脑突触体的脂质过氧化产物丙二醛及胞内钙离子浓度显著上升,突触体的膜流动性和Na~ ／K~ -ATP酶的活性则显著下降,预先加入灯盏花乙素(25-100μmol／L)则能显著缓解超氧阴离子引起的氧化性损伤,表现为丙二醛的水平和胞内钙离子浓度下降,膜流动性增加及Na~ ／K~ -ATP酶活性的恢复．结论：灯盏花乙素对超氧阴离子引起的大鼠脑突触体氧化应激具有良好的保护作用．     

Scavenging of reactive oxygen species by Eriobotrya japonica seed extract

We have clarified that Eriobotrya japonica seed extract has strong antioxidative activity, and is effective for the prevention and treatment of various diseases, such as hepatopathy and nephropathy. In this study, to investigate the influences of components of Eriobotrya japonica seed extract on its antioxidative activity, extracts were prepared using various solvents (n-hexane (Hex), ethyl acetate (EtOAc), n-butanol (n-BuOH), methanol (MeOH) and H2O) and the antioxidative activity of the solvent fractions and components was evaluated based on the scavenging of various radicals (DPPH and O2(-)) measured by the ESR method and the inhibition of Fe3+-ADP induced NADPH dependent lipid peroxidation in rat liver microsomes. The radical scavenging activities and inhibitory activities on lipid peroxidation differed among the solvent fractions and components. In the n-BuOH, MeOH and H2O fractions, radical scavenging activity and inhibitory activity on lipid peroxidation were high. In addition, these fractions contained abundant polyphenols, and the radical scavenging activity increased with the polyphenol content. In the low-polar Hex and EtOAc fractions, the radical scavenging activity was low, but the lipid peroxidation inhibition activity was high. These fractions contained beta-sitosterol, and the inhibitory activity on lipid peroxidation was high. Based on these findings, the antioxidative activity of Eriobotrya japonica seed extract may be derived from many components involved in a complex mechanism, resulting in high activity.     

Time-dependent changes of lipid peroxidation and antioxidative status in nerve tissues of hens treated with tri-ortho-cresyl phosphate (TOCP)

Tri-ortho-cresyl phosphate (TOCP) could induce a delayed neurodegenerative condition known as organophosphorus easter-induced delayed neurotoxicity (OPIDN) in human beings and sensitive animals. However, the mechanisms of OPIDN remain unknown. This study investigated the time-dependent changes of the lipid peroxidation (malondialdehyde, MDA) and antioxidative status (glutathione, GSH; glutathione peroxidase, GSH-Px; glutathione reductase, GR; superoxide dismutase, SOD and anti-reactive oxygen species, anti-ROS) in nerve tissues for elucidating the mechanism of OPIDN induced by TOCP. Adult hens were treated with TOCP by gavage at a single dosage of 750 mg/kg. TOCP was dissolved in corn oil and administered at 0.65 ml/kg. The control hens received an equivalent volume of corn oil by gavage. Hens were sacrificed after 0, 5, 10, 15 and 21 days of treatment and the cerebrum, spinal cord, sciatic nerve were dissected, homogenized and used for the determination of lipid peroxidation and antioxidative status. The results showed that treatment with TOCP increased lipid peroxidation and reduced the antioxidative status in cerebrum, spinal cord and sciatic nerve. The levels of MDA increased by 33% (P<0.01) in cerebrum on 5th day after TOCP treatment and at clinical sign score of 1-2, and increased respectively by 32% and 15% (P<0.01) in spinal cord and sciatic nerve on 10th day after TOCP treatment and at clinical sign score of 3-4. Further changes of MDA were also observed after 15 and 21 days post-dosing and at clinical sign score of 5-6 and 7-8. There is a decrease in the activities of SOD, GSH-Px, GR, anti-ROS, and GSH content in cerebrum, spinal cord and sciatic nerve of hens after 5, 10, 15 and 21 days post-dosing and at clinical sign score of 1-2, 3-4, 5-6 and 7-8. Thus, OPIDN induced by TOCP was associated with elevation of lipid peroxidation and reduction of antioxidative status, and the time-dependent changes of these indexes in hens nerve tissues occurred. Sciatic nerve was the main target tissue and MDA was most sensitive among all indexes. The time-dependent and tissue specific changes of lipid peroxidation and antioxidative status in cerebrum, spinal cord and sciatic nerve suggest that ROS and concomitant lipid peroxidation, at least in part, are involved in the toxic effects of TOCP on nerve tissues and that oxidative stress may play a role in the occurrence and development of OPIDN induced by TOCP.     

Lipid peroxidation induced by indomethacin with horseradish peroxidase and hydrogen peroxide: involvement of indomethacin radicals

Some of the side-effects of using indomethacin (IM) involve damage to the gastric mucosa and liver mitochondria. On the other hand, neutrophils infiltrate inflammatory sites to damage the tissues through the generation of reactive oxygen species by myeloperoxidase. The stomach and intestine have large amounts of peroxidase. These findings suggest that peroxidases are involved in tissue damage induced by IM. To clarify the basis for the tissue damage induced by IM in the presence of horseradish peroxidase (HRP) and H2O2 (HRP-H2O2), lipid peroxidation was investigated. When IM was incubated with liver microsomes in the presence of HRP-H2O2 and ADP-Fe3+, lipid peroxidation was time-dependent. Catalase and desferrioxamine almost completely inhibited lipid peroxidation, indicating that H2O2 and iron are necessary for lipid peroxidation. Of interest, superoxide dismutase strongly inhibited lipid peroxidation, and it also inhibited the formation of bathophenanthroline-Fe2+, indicating that reduction of the ferric ion was due to superoxide (O2-). ESR signals of IM radicals were detected during the interaction of IM with HRP-H2O2. However, the IM radical by itself did not reduce the ferric ion. These results suggest that O2- may be generated during the interaction of IM radicals with H2O2. Ferryl species, which are formed during the reduction of iron by O2-, probably are involved in lipid peroxidation.     

Ebselen对自由基诱发的皮层神经元和皮层线粒体脂质过氧化损伤的保护作用

观察了ebselen对超氧阴离子O^·-₂和羟自由基·OH诱发的体外培养大鼠皮层神经元乳酸脱氢酶(lactic dehydrogenase,LDH)释放,和TBARS(thiobarbituric acid reactive substance)含量升高及制备的皮层线粒体TBARS含量升高的影响。结果表明:超氧阴离子和羟自由基引起了培养神经元和线粒体明显的损伤。浓度在5～50μmol·L^-1之间,ebselen能剂量依赖性地抑制LDH释放和TBARS含量的增加,对线粒体的TBARS含量升高也有显著的抑制作用。但浓度为0.2～50μmol·L^-1时,药物无直接清除超氧阴离子和羟自由基的活性。因此,ebselen对氧自由基诱发的神经元脂质过氧化损伤有拮抗作用,这种作用与直接清除自由基无关。