Effects of erdosteine on acetaminophen-induced hepatotoxicity in rats

We investigated the effects of erdosteine on acetaminophen (APAP)-induced hepatotoxicity in rats. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), AST (aspartate aminotransferase), and ALT (alanine transaminase) activities, and malonyldialdehyde (MDA) and nitric oxide levels as oxidant/antioxidant biochemical parameters were investigated with light microscopic evaluation in adult female Wistar Albino rats. APAP administration produced a decrease in hepatic SOD, CAT, and GSH-Px activities, and coadministration of erdosteine (150 and 300 mg/kg) resulted in increases in the activities. MDA and NO levels increased in the APAP group, and erdosteine treatments prevented these increases. Significant elevations in serum AST and ALT levels were observed in the APAP group, and when erdosteine and APAP were coadministered, their serum levels were close to those in the control group. Light microscopic evaluation of livers showed that there were remarkable centrilobular (zone III) hepatic necrosis and mild to moderate sinusoidal congestion in the APAP group, whereas in the erdosteine group, cellular necrosis was minimal and the hepatocytes maintained a better morphology when compared to the APAP group. Erdosteine prevented APAP-induced liver injury and toxic side effects probably through the antioxidant and radical scavenging effects of erdosteine.     

富硒酵母对铁过量导致小鼠肝损伤保护作用的实验研究

目的研究不同剂量的富硒酵母对铁过量导致小鼠肝脏脂质过氧化水平和细胞凋亡的影响。方法通过腹腔注射右旋糖酐铁6周诱发小鼠肝损伤后,分别给予不同剂量的富硒酵母,观察补硒对小鼠肝脏丙二醛（MDA）含量,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）的活性及肝组织细胞凋亡的影响。结果与模型组相比,补充富硒酵母40 mg/（kg·d）能显著降低肝组织中MDA含量,增强SOD、CAT、GSH-Px的活性,并能减少细胞的凋亡;而补充富硒酵母20,60 mg/（kg.d）能显著增加MDA含量,降低SOD、CAT、GSH-Px的活性,并能增加肝细胞的凋亡。结论富硒酵母具有抗氧化和促氧化的双向作用,其两面性取决于硒的浓度。     

Alterations in the erythrocyte antioxidant system of blood stored in blood bags

In the present study, we measured the concentrations of reduced glutathione (GSH) and malonyldialdehyde (MDA) and the activities of glutathione peroxidase (GSH-Px), glutathione S-transferase (GSH-S-T), superoxide dismutase (SOD), catalase (CAT) and glucose-6-phosphate dehydrogenase (G-6-PD) in erythrocytes obtained freshly from adult male donors which was preserved with CPDA-1 anticoagulant (citrate,phosphate, dextrose, adenine) on different days of storage. At the end of the study, storage-associated alterations in antioxidant activities were noted and discussed. GSH, GSH-Px, GSH-S-T, SOD, CAT and G-6-PD activities decreased, but erythrocyte MDA levels, as anindex of lipid peroxidation, increased during the storage period. According to our results, glutathione-dependent antioxidant systems in erythrocytes might be depleted during long storage in blood bags.     

Status of lipid peroxidation and antioxidant enzymes in goats naturally infected with Babesia ovis

This study aimed to assess lipid peroxidation and antioxidant enzymes in goats naturally infected with Babesia ovis. Red blood cell count (RBC), hemoglobin (Hb) concentration, packed cell volume (PCV), malondialdehyde (MDA) concentration, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) activities and total antioxidant capacity (TAC) were determined in 15 goats naturally infected with B. ovis as well as same number of healthy goats. The parasitological diagnosis was confirmed using polymerase chain reaction (PCR) analysis by amplifying a partial 18S rRNA gene sequence of B. ovis. Percentage of parasitemia varied from 0.01 to 1%. The activities of erythrocyte GSH-Px, SOD, CAT and TAC were significantly lower (p<0.05) in the infected goats than in healthy ones. MDA concentration in erythrocytes of infected goats was significantly higher in infected goats than in healthy ones (p?0.05). Severity of parasitemia showed a positive correlation with the MDA and negative correlation with PCV, SOD, CAT, GSH-Px and TAC. Also, MDA was negatively correlated with PCV, SOD, CAT, GSH-Px and TAC. The results of this study suggested that oxidative damage to RBCs may contribute to the pathogenesis of anemia in caprine babesiosis.     

Protective role of aminoguanidine on gentamicin-induced acute renal failure in rats

The toxicity of aminoglycosides including gentamicin (GEN), the most widely used drug in this category, is believed to be related to the generation of reactive oxygen species (ROS) in the kidney. Aminoguanidine (AG) is known as an effective antioxidant and its free radical scavenger effects may protect GEN-induced acute renal failure (ARF). Therefore, this study was focused on investigating the possible protective effect of AG against GEN-induced nephrotoxicity in an in vivo rat model. We investigated the effects of AG on GEN-induced changes in renal tissue malondialdehyde (MDA) levels; nitric oxide (NO) generation; glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities; glutathione (GSH) content; serum creatinine (Cr) and blood urea nitrogen (BUN) levels. Morphological changes in the kidney were also examined using light microscopy. GEN administration to control group rats increased renal MDA and NO levels but decreased GSH-Px, SOD, CAT activities and GSH content. AG administration with GEN injection resulted in significantly decreased MDA, NO generation and increased GSH-Px, SOD, CAT activities and GSH content when compared with GEN alone. Serum levels of Cr and BUN significantly increased as a result of nephrotoxicity. Also, AG significantly decreased Cr and BUN levels. Morphological changes in the kidney, including tubular necrosis, intracellular edema, glomerular and basement membrane alterations were evaluated qualitatively. Both biochemical findings and histopathological evidence showed that administration of AG reduced the GEN-induced kidney damage. We propose that AG acts in the kidney as a potent scavenger of free radicals to prevent the toxic effects of GEN both at the biochemical and histological level.     

Influence of polychemotherapy on the antioxidant levels and lipid peroxidation in patients with lymphoproliferative diseases

The purpose of the present study was to compare the oxidative stress parameters such as the extent of lipid peroxidation and the status of antioxidants in patients with lymphoproliferative diseases. The effect of polychemotherapy on the level of lipid peroxidation products and on the activities of antioxidant defense enzymes was also investigated. Lipid peroxidation (malondialdehyde or MDA), superoxide dismutase (SOD), catalase (CAT), and ceruloplasmin (CER) activities, were measured in 58 patients with non-Hodgkins lymphoma, Hodgkins disease, chronic lymphocytic leukemia, and acute lymphoblastic leukemia before treatment, during and after polychemotherapy. Plasma levels of MDA and CER in plasma were increased in comparison with the control group before any treatment. Erythrocyte SOD activity was significantly lower but CAT activity was significantly higher in patients than those in controls. Moreover, the levels of MDA and CER increased by the effect of the different regimens of polychemotherapy, which appeared to be compromised by augmented activity of antioxidant enzymes SOD and CAT. The levels of plasma MDA were found to be significantly higher in comparison to the control group for patients treated with cyclophosphamide, vincristine, prednisolon (CVP) and adriamicine, bleomicine, vinblastine, dacarbasine (ABVD), (p<0.01). Erythrocyte SOD statistically decreased (p<0.001) and CAT activities statistically increased in patients treated with CVP and ABVD (p<0.001). In conclusion, our results suggest that after polychemotherapy, the oxidative stress and the imbalance of antioxidant enzyme systems significantly progresses in patients with lymphoproliferative hematological diseases. Patients treated with CVP and ABVD are at the biggest risk of oxidative injury. Thus, the antioxidant status of cancer patients may play an important role in their response to chemotherapy.     

Evaluation of oxidative stress in erythrocytes of guinea pigs with experimental otitis media and effusion

Oxygen free radicals (OFRs) have been implicated in the pathogenesis of an increasing number of diseases and inflammatory states. They may cause cell and tissue damage by their chemical modification of proteins, carbohydrates, nucleotides, and lipids. Under physiological conditions OFRs are part of normal regulatory circuits and are neutralized by antioxidants. Infections are one cause of increased OFR production. The aims of our study were to assess whether the increased oxidative stress in experimental otitis media with effusion (OME) is reflected in erythrocytes by lipid peroxidation and to survey the alterations in oxidant and antioxidant enzyme activities in experimental OME in guinea pigs. Erythrocyte total (enzymatic plus non-enzymatic) superoxide scavenger activity (TSSA), non-enzymatic superoxide scavenger activity (NSSA), superoxide dismutase (SOD), catalase (CAT), and xanthine oxidase (XO) activities, and malondialdehyde (MDA) level were measured in 6 guinea pigs with OME and in 6 controls. The TSSA, SOD, XO activities, and MDA level in experimental OME were significantly higher than in controls. No significant differences were found in erythrocyte NSSA and CAT activities. In experimental OME induced by histamine injection, increased OFR production was observed, suggesting that OFRs may play an important role in cell and tissue damage due to OME.     

Catechin protects against oxidative stress and inflammatory-mediated cardiotoxicity in adriamycin-treated rats

Catechin has anti-inflammatory and antioxidative effects. Cardiotoxicity, which results from intense cardiac oxidative stress and inflammation, is the main limiting factor of the adriamycin use in the treatment of malignant tumors. Thus, the present study aimed to assess the antioxidant and anti-inflammatory effects of catechin on adriamycin-induced cardiotoxicity in rats. Forty-five rats were allocated to three groups: control group, adriamycin group and adriamycin?+?catechin group. We performed the following measurements: lipid peroxidation (MDA), catalase (CAT), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities as well as, the expression of inflammatory cytokines genes namely nuclear factor kappa-B, tumor necrosis factor and inducible nitric oxide synthase. Catechin administration significantly decreased MDA level and significantly increased CAT, GSH-Px and SOD activities. Also, catechin significantly decreased the expression levels of inflammatory cytokines. Catechin provided cardioprotection on adriamycin-induced cardiotoxicity through their antioxidant and anti-inflammatory properties.     

糖尿病大鼠肾脏组织氧化应激及其在糖尿病肾病发病中的意义

目的：观察糖尿病大鼠肾脏组织中氧化应激水平，探讨氧化应激在糖尿病肾病中的作用。 方法： 糖尿病模型鼠采用STZ诱导。36只大鼠随机分为正常对照组、糖尿病维持组、糖尿病治疗组。喂养至12周，测定各组血糖、血中胆固醇、甘油三酯、尿素氮、肌酐、糖化血红蛋白水平、尿肌酐水平和24 h尿蛋白含量。运用比色法测定肾脏皮质中抗氧化酶的活性,包括总超氧化物歧化酶（TSOD）、铜锌超氧化物歧化酶(Cu-Zn SOD)、锰超氧化物歧化酶（Mn SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶(GSH-Px)以及丙二醛（MDA）的含量。逆转录聚合酶链式反应（RT-PCR）半定量测定肾脏组织中各抗氧化酶mRNA的表达水平。 结果： 糖尿病治疗组与正常对照组间各指标无显著差异。糖尿病维持组中血糖、胆固醇、甘油三酯、糖化血红蛋白明显高于糖尿病治疗组和正常对照组；抗氧化酶中，TSOD 、Cu-Zn SOD、CAT活性明显低于糖尿病治疗组和正常对照组，GSH-Px活性则高于糖尿病治疗组和正常对照组，Mn SOD活性在各组中无显著差异；而MDA水平则明显高于糖尿病治疗组和正常对照组。糖尿病维持组中GSH-Px、Cu-Zn SOD的mRNA表达水平高于其它组，而CAT mRNA的表达则低于其它组，Mn SOD的mRNA表达水平在各组无明显差异。糖尿病维持组尿蛋白含量明显高于其它组，而肌酐清除率则明显低于其它组。 结论： 高血糖可以影响大鼠肾脏组织中抗氧化酶的表达，升高糖尿病大鼠肾脏组织的氧化应激水平,在糖尿病肾病发病机制中起重要作用。     

配比油对家兔体内抗氧化酶类活性的影响

观察不同配比n-3,n-6系脂肪酸的配比油对家兔体内几种抗氧化酶活性的影响，实验用家兔，共50只随机分为5组。对照组喂饲基础饲料，高脂组喂饲富含猪油和胆固醇（Ch)的饲料，配比油组（配比1组。配比2组，配比3组）喂饲的饲料中除了猪油和胆固醇外，还有不同配比n-3,n-6系脂肪酸的配比油，实验三个月中每间隔一个月耳缘静脉取血一次，检测各组家兔红细胞中超氧化物歧化酶（SOD）。过氧化氢酶（CAT），谷胱甘肽过氧化物酶9GSH-Px)。活性的变化，结果表明配比油使SOD，CAT活性均明显增强，但不同油脂对GSH-Px活性的影响较复杂，说明不同配比n-3,n-6系脂肪酸的混合油均可增强抗氧化系统酶活性，其增强作用与不同配比剂量密切相关。     

脂多糖对化学诱癌大鼠抗氧化系统的选择性损害作用

目的：观察脂多糖对化学诱癌大鼠抗氧化系统的影响。方法：用０３ｇ／Ｌ硫代乙酰胺给大鼠饮用６个月,诱发肝硬化癌变模型。大鼠在实验前作脾切除造成肠源性内毒素血症或／和在肝硬化形成时给予外源性脂多糖。结果：无论是外源性或／和肠源性内毒素均可提高肝硬化大鼠内毒素血症水平和肝癌发生率增加趋势。肝内丙二醛（ＭＤＡ）含量、超氧化物歧化酶（ＳＯＤ）活性不同程度地增高、而谷胱甘肽过氧化物酶（ＧＳＨ－Ｐｘ）和过氧化氢酶（ＣＡＴ）活性呈降低趋势,并与ＭＤＡ浓度呈明显负相关（Ｐ＜００５）。结论：抗氧化酶类代谢紊乱、特别是ＣＡＴ活性降低可能与肝硬化癌变的发生发展有关     

苦参素降低大鼠肾脏缺血-再灌注损伤

目的观察苦参素的抗大鼠肾缺血再灌注损伤的作用并从抗氧化方面探讨其机制。方法用双肾肾蒂夹闭45 min建立IRI模型,将SD大鼠随机分为假手术组(sham);缺血再灌注组(I/R);苦参素治疗组(oxymatrine+I/R)。苦参素治疗组又分为高、中和低3个剂量组,在缺血再灌注前,连续7 d经腹腔注射。用自动生化仪测定血清肌酐(Scr)和尿素氮(BUN)水平,观察苦参素对肾缺血再灌注的保护作用及确定最优剂量;以最优剂量干预用分光分析法测定肾组织丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)水平。结果不同剂量组均能明显减轻肾脏IRI的病理形态学改变,改善肾功能。与I/R组相比,再灌注72 h后,MDA水平,血清肌酐(Scr)和尿素氮(BUN)水平明显降低(P<0.05);苦参素治疗组的CAT、T-SOD、GSH-Px活性改善明显(P<0.05)。苦参素无体外抗氧化作用。结论苦参素对大鼠肾缺血再灌注损伤具有保护作用,作用机制可能与调控机体的抗氧化系统有关。     

Vitamin combinations reduce oxidative stress and improve antioxidant status in patients with iron deficiency anemia

The purpose of the present study was to investigate whether oxidative stress occurs at the clinical onset of iron deficiency anemia and to find the influence of iron therapy and antioxidant vitamins on the oxidative stress parameters. A comparison was made with two other categories of anaemia, pernicious anaemia and haemolytic anaemia that are not characterized with iron deficiency. Oxidative stress was measured through the level of plasma lipid peroxidation (MDA) and the activities of ceruloplasmin (CP), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px); important extracellular and intracellular antioxidants. Significantly increased lipid peroxidation was demonstrated in the plasma of patients with iron deficiency anemia (P=0.005). While the activity of erythrocyte antioxidant enzyme GSH-Px remained unaltered, SOD was significantly decreased (P <0.05), CAT and plasma CP were significantly increased (P <0.001). Repletion of iron deficient patients with iron promotes oxidative stress: MDA was found to remain high, the activities of SOD and GSH-Px remained lower and CAT remained very high as before iron treatment. When iron deficient patients were treated with iron along with the antioxidant vitamins A, E and C, the oxidative stress was reduced and the activity of SOD was normalized. The combination of Vitamins A+E and Vitamin C is more effective than Vitamin C in reversing antioxidant status. In conclusion, our results demonstrated that increased oxidative stress is present in patients with iron deficiency anemia which appears to be compromised by imbalance in antioxidant defense systems. The repletion of iron deficient patients with iron promotes the oxidative stress. Patients with iron deficiency anemia after iron treatment actually are at risk of oxidative injury. Iron in the presence of the antioxidant vitamins A+E and ascorbic acid reduced the oxidative stress.     

Dehydroepiandrosterone improves hepatic antioxidant systems after renal ischemia-reperfusion injury in rabbits

This study evaluated the effects of dehydroepiandrosterone (DHEA) on the oxidant [malondialdehyde (MDA)] and antioxidant [superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and glutathione (GSH)] systems in liver after renal ischemia-reperfusion (IR) injury in rabbits. Thirty rabbits were randomly assigned to 3 groups of 10: group I (sham operation), group II (renal IR group), and group III (DHEA, 25 mg/kg, s.c., 15 min pre-ischemia). Renal IR injury in group II caused a decrease of SOD (25%), GPx (36%), and CAT (26%) activities and GSH levels (32%), and increases of MDA (30%) in liver and of ALT and AST activities in serum, compared to group I. DHEA administration decreased the hepatic MDA level (19%) and serum ALT activity (30%) (p <0.01 and p <0.05, respectively), and considerably increased hepatic GSH levels and GPx activities (p <0.01 for both) in group III, compared to group II. These results suggest that DHEA treatment has beneficial effects on antioxidant defenses against hepatic injury after renal IR in rabbits, possibly by augmenting GSH levels and lowering MDA production.     

Functions of antioxidant enzyme activities on the membrane bound total sialic acid and lipid peroxidation level in F. equiseti and F. acuminatum

The variations of membrane bound total sialic acid (TSA) and lipid peroxidation level dependent on the antioxidant enzyme activities such as Superoxide Dismutase (SOD), Catalase (CAT), Glutathione peroxidase (GSH-Px) have been studied in yeast extract supplemented medium. The maximum SOD and CAT activities of F. equiseti tended to increase with raises of yeast extract concentration up to 25 g/L where they were determined to be 78.6 +/- 0.96 and 312.7 +/- 5.6 IU/mg. On the other hand, SOD and CAT activities in F. acuminatum significantly increased with the rise of yeast extract concentration up to 10 g/L (p < 0.01) and maximum activities were observed at this concentration as 36.3 +/- 0.54 and 115.3 +/- 2.19 IU/mg on the 12th day incubation. Other H2O2 scavenger enzyme, GSH-Px activities of F. equiseti and F. acuminatum were reached the maximum at 5 and 25g/L yeast extract and determined as 5.06 +/- 0.04 and 4.74 +/- 0.09 IU/mg, respectively. TSA level showed positive correlation with SOD and CAT activities while LPO levels variations negatively correlated. The results may indicate that these antioxidant enzymes also appeared to be involved in protecting membrane bound sialic acids as well as membrane lipid of the fungus from exogenous reactive oxygen species.     

高压氧与环孢素A对皮肤移植小鼠脾活性氧及一氧化氮含量的影响

目的:探讨高压氧与环孢素A对皮肤移植小鼠脾中活性氧、一氧化氮含量的影响。方法:供鼠BALB/C,受鼠C⁵⁷BL/6,皮肤移植,环孢素A组每日腹腔注射CsA5mg/kg,高压氧(HBO)组每日用99.2%氧气0.25MPa作用1.5h,14d后,取脾称重,测脾中丙二醛(MDA)的含量,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)的活性和一氧化氮(NO)的含量,一氧化氮合酶(NOS)的活性。结果:(1)移植组、高压氧组和环孢素A组的MDA含量,GSH-PX、CAT的活性均高于对照组;环孢素A组GSH-PX、CAT活性低于、SOD的活性高于移植组;高压氧组GSH-PX活性低于、CAT和SOD活性高于移植组(P<0.01)。(2)移植组的NOS活性及NO含量高于对照组;高压氧组的NO含量低于、NOS活性高于移植组(P<0.01);环孢素A组的NO含量、NOS活性变化无显著意义。结论:皮肤移植小鼠脾细胞过氧化增强,NO含量及NOS活性增高;高压氧与环孢素A对上述二个系统具有一定作用,这可能与其抑制排斥反应有关。     

Ethanol induced adaptive changes in blood for the pathological and toxicological effects of chronic ethanol consumption in humans

Alcohol consumption is associated with a number of toxicological changes in blood and the oxidant–antioxidant system. The present study was performed to investigate the alcohol induced toxicological, pathological changes in blood and an adaptive role of erythrocyte antioxidant system in chronic alcoholics. Human male volunteers aged 44 ± 6 years with similar dietary habits were divided into two groups, namely non-alcoholic controls and chronic alcoholics. We measured hematological parameters, erythrocyte lipid peroxidation, NO production, erythrocyte antioxidant and liver function test enzyme activities. Alcoholics had increased erythrocyte nitric oxide levels and also elevated erythrocyte lipid malondialdehyde (MDA) concentrations. Strikingly, increments in reduced glutathione and markedly increased activities of certain antioxidant enzymes such as glutathione reductase (GR), superoxide dismutase (SOD), and another related enzyme G-6 phosphate dehydrogenase (G6-PDH) with no alterations in the activities of glutathione S-transferase (GST), glutathione peroxidase (GPx), and catalase (CAT) in chronic alcoholics were observed compared to controls. Furthermore, erythrocyte NO levels were positively correlated with lipid peroxidation, SOD, GSH, GR and G6PDH in chronic alcoholics. In addition, increased AST/ALT ratio and a significant increase in WBC and platelets were also noticed. Together, these results indicate that, antioxidants and defense enzymes appear to be rendering protection as a consequence of chronic adaptation in alcoholics.     

NG-硝基-L-精氨酸对大鼠内毒素性肺线粒体损伤的影响

目的： 观察非选择性一氧化氮合酶(NOS)抑制剂NG-硝基-L-精氨酸(L-NA)对急性肺损伤大鼠肺线粒体功能的影响，并探讨其改善急性肺损伤的作用机制。方法: 将SD大鼠随机分为空白对照组、急性肺损伤组、L-NA治疗组，采用舌静脉注射脂多糖(LPS)复制大鼠急性肺损伤模型，于大鼠急性肺损伤3h后给L-NA治疗3h，断头放血处死大鼠，迅速取出肺脏，匀浆器混匀后，低温差速离心法提取肺线粒体，测定线粒体总ATP酶、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）、总一氧化氮合酶（T-NOS）、诱生型一氧化氮合酶（iNOS）、结构型一氧化氮合酶（cNOS）的活性，以及线粒体肿胀度、膜流动性和线粒体一氧化氮（NO）、丙二醛（MDA）含量；电镜观察大鼠肺线粒体超微结构的改变及治疗药对此改变的影响。结果: 在大鼠内毒素性急性肺损伤后，肺脏组织中线粒体表现为肿胀、膜流动性降低，线粒体中的T-NOS和iNOS活性显著升高，线粒体NO生成明显增加，而cNOS活性无明显变化；线粒体总ATP酶、SOD、GSH-Px活性均明显下降，线粒体MDA含量明显升高。急性肺损伤3h给予L-NA治疗3h,与急性肺损伤组相比，一氧化氮合酶活性有所改变，NO生成显著下降，总ATP酶、SOD、GSH-Px活性均显著升高，MDA含量下降。电镜结果显示内毒素性急性肺损伤后肺脏组织细胞水肿，线粒体肿胀、嵴断裂、溶解、消失；L-NA能改善内毒素性急性肺损伤引起的细胞水肿、线粒体肿胀和空泡化。结论: L-NA能明显抑制急性肺损伤后线粒体一氧化氮合酶活性，减少NO生成，改善线粒体能量供应，增加线粒体抗氧化作用，从而减轻急性肺损伤。     

Protective effect of melatonin on experimental otitis media with effusion in guinea pigs

The aims of this study were: (a) to assess whether the increased oxidative stress in otitis media with effusion (OME) induced in guinea pigs by histamine injection into the middle ear cavity is reflected by lipid peroxidation in erythrocytes, plasma, and middle ear effusion fluid; (b) to survey the alterations of oxidant and antioxidant enzyme activities in experimental OME; and (c) to determine the effects of melatonin and methylprednisolone on this oxidative stress. Malondialdehyde (MDA) level, erythrocyte total (enzymatic plus non-enzymatic) superoxide scavenger activity (TSSA), non-enzymatic superoxide scavenger activity (NSSA), superoxide dismutase (SOD), catalase (CAT), and xanthine oxidase (XO) activities were measured in 4 groups of 7 guinea pigs at 3 hr after injection of 0.1 ml of histamine (or saline) into the middle ear. Group I was the control group, Group II was an experimental group with OME induced by histamine, Group III was a melatonin-pretreated OME group, and Group IV was a methylprednisolone-pretreated OME group. In erythrocyte, plasma, and middle ear effusion samples, MDA levels were significantly increased in guinea pigs with OME (Group II), compared to controls (Group I); erythrocyte TSSA and SOD activities were lower and erythrocyte XO activity was increased in guinea pigs with OME (Group II) compared to controls (Group I). No significant differences were found in erythrocyte NSSA and CAT activities. In Group III, pretreatment of guinea pigs with i.p. melatonin at 1 hr prior to histamine induction of OME decreased the erythrocyte, plasma, and effusion MDA levels, compared to Group II; erythrocyte XO activity was diminished and erythrocyte TSSA, SOD, and CAT activities were increased in Group III compared to Group II. In Group IV, pretreatment of guinea pigs with i.p. methylprednisolone at 1 hr prior to histamine induction of OME decreased the plasma and effusion MDA levels and increased the erythrocyte TSSA and SOD activities, compared to Group II. These results suggest that reactive oxygen species (ROS) play a role in histamine-induced OME. Pretreatment with i.p. melatonin or methylprednisolone both decrease the ROS generated by experimental OME, but melatonin appears to be more effective than methylprednisolone.     

中华眼镜蛇毒C组分对荷人胶质细胞瘤株U-251裸鼠血清抗氧化酶活性的影响

目的探讨中华眼镜蛇毒C组分对荷人胶质细胞瘤株U-251裸鼠血清抗氧化酶活性的影响。方法取荷人胶质细胞瘤株U-251的Balb/c裸鼠,经腹腔注射低、中、高浓度的FCNNAV1mg/L、5mg/L、10mg/L,采用比色法检测裸鼠血中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、丙二醛(MDA)和谷胱甘肽过氧化物酶(GSH-PX)活性。结果荷人胶质细胞瘤株U-251裸鼠血清SOD、GSH-PX、CAT活性显著高于正常裸鼠组(P<0.05),MDA含量显著低于正常裸鼠组(P<0.05)。结论中华眼镜蛇毒C组分的抑瘤作用可能与其提高荷瘤鼠血血清抗氧化酶活性的影响有关。