Antagonistic Effect In Vivo of Zinc on Inhibition of δ -Aminolevulinic Acid Dehydratase by Lead

δ-aminolevulinic acid dehydratase (ALAD) is an enzyme involved in the biosynthesis of heme, in which it catalyzes the condensation of two molecules of δ-aminolevulinic acid to one molecule of porphobilinogen. It is a sulfhydryl enzyme, which means, among other tilings, that its activity is inhibited by many heavy metals. In the present investigation rabbits were given either zinc or lead or both. Zinc had a strong activating effect on ALAD in vivo, and the inhibitory effect of lead was almost completely eliminated. A close positive correlation was found between ALAD in the red blood cells and zinc in the plasma, but there was no correlation between ALAD and zinc in the red blood cells. These observations are of particular interest in the light of recent findings, suggesting that zinc is an essential metal for ALAD.     

Dual effects of molybdenum on mouse oocyte quality and ovarian oxidative stress

A sub-acute toxicity test was performed to investigate the effects of molybdenum (Mo) on ovarian function. ICR adult female mice were exposed to Mo by free access to distilled water containing the Mo at 5, 10, 20, and 40?mg/L for 14 days. Compared to the control group, M?II oocyte morphology, ovary index, and ovulation improved within the 5?mg/L Mo group, but were negatively affected by Mo at 40?mg/L. Morphologically abnormal ovarian mitochondria were observed at?≥?20?mg/L. These alterations accompanied the changes in superoxide dismutase (SOD), glutathione peroxidise (GPx), and malondialdehyde (MDA) levels in ovaries. In conclusion, Mo affects oocyte quality possibly through regulating ovarian oxidative stress in a dose-dependent manner. It appears that Mo may improve ovarian function at a suitable concentration, which might be a candidate for the treatment of female infertility.     

Protective Effect of Plumbago zeylanica Against Cyclophosphamide-Induced Genotoxicity and Oxidative Stress in Swiss Albino Mice

Plumbago zeylanica, commonly known as white leadwort, found abundantly in the plains of Bengal and southern India, was tested for its possible in vivo protective effect against cyclophosphamide-induced genotoxicity and oxidative stress in Swiss albino mice. Pretreatment with the alcoholic root extract of Plumbago zeylanica (250 and 500 mg/kg body weight orally for 5 days) significantly reduced the frequency of micronucleated polychromatic erythrocytes (MnPCEs), increased the PCE/NCE (normochromatic erythrocyte) ratio in the bone marrow, and decreased the levels of lipid peroxidation products with concomitant changes in the status of antioxidants. Both doses of Plumbago zeylanica were effective in exerting a protective effect against cyclophosphamide-induced genotoxicity and oxidative stress.     

Reversal of Hyperoxaluria-Induced Alteration in Rat Liver by Administration of N-Acetylcysteine

The current work was designed to study the potential of N-acetylcysteine (NAC) in modulating hyperoxaluric manifestations induced by acute oxalate dose in rat liver. Hyperoxaluric conditions were induced by giving a single dose of sodium oxalate (70 mg/kg body weight) in one group, and in the other group, hyperoxaluric rats were administered NAC (200 mg/kg body weight) after 30 min of the oxalate dose. After 12 h of the above treatment, blood was taken from the orbital sinus for testing serum oxalate, and animals were sacrificed. To exploit the potential of NAC, various oxidative stress parameters [lipid peroxidation (LP) and activity of antioxidant enzymes], lipid content, and histologic analysis of rat liver were performed. The increased level of LP and activities of superoxide dismutase and catalase in hyperoxaluric rats were restored after NAC treatment. Not only the decreased amount of total lipids and phospholipids but also the increased ratio of cholesterol/phospholipid (showing decreased membrane fluidity) in hyperoxaluric rats were balanced by NAC treatment. Further restored histologic changes of liver tissue confirmed the protective antioxidant effects of the given drug. Thus, N-acetylcysteine being an extraneous antioxidant showed curative properties toward hyperoxaluric manifestations in liver.     

Toxicity of ricin toxin A chain in rats

Ricin toxin A chain (RTA) is the cytotoxic component of the dimeric protein, ricin, one of the most potent and deadly plant toxins extracted from the seeds of Ricinus communis. RTA has been investigated as a potential candidate for cancer chemotherapy, in the form of immunotoxins, and as a method for depleting macrophages in vivo. The toxicity of RTA immunotoxins is mostly characterized by inflammation and necrosis and has been attributed to the RTA moiety of the conjugate. The present study was carried out to investigate the toxicity of intravenously (i.v.) administered RTA alone and to assess whether the observed tissue injuries are associated with increases in oxidative stress (OS) and inflammation. RTA (10 or 90 µg/kg body weight) was administered to animals i.v., and 5 or 24 hours later, liver, lungs, kidneys, and hearts were examined. RTA, at a dose of 90 µg/kg (i.v.), resulted in significant increases (P < 0.05) in an inflammatory response (i.e., increases in hepatic and lung myeloperoxidase activity) and increases in oxidant response (increases in lipid peroxidation and decreases in glutathione levels in hepatic and lung homogenates). These data suggest that i.v. administration of RTA resulted in organ injuries that were associated with inflammation and OS.     

Dimethylbenz[α]anthracene induces oxidative stress and reduces the binding capacity of the mitochondrial 18-kDa translocator protein in rat aorta

In this study, rats surviving 18 weeks after 7,12-dimethylbenz[a]anthracene (DMBA) exposure showed robust pathological changes in the aorta. This correlated well with decreases in 18-kDa translocator protein (TSPO) binding capacity in this tissue. As expected, markers for oxidative stress, including thiobarbituric-acid–reactive substances, and advanced oxidation protein products, showed that the applied DMBA exposure increased oxidative stress in the aorta. Our study suggests that TSPO may be involved in toxic DMBA effects in the aorta, including inflammatory responses and reactive oxygen species generation.     

Protective effect of extract of Crataegus pinnatifida pollen on DNA damage response to oxidative stress

The protective effect of extract of Crataegus pinnatifida (Rosaceae) pollen (ECPP) on the DNA damage response to oxidative stress was investigated and assessed with an alkaline single-cell gel electrophoresis (SCGE) assay and pBR322 plasmid DNA breaks in site-specific and non-site-specific systems. Total phenolic content, total flavonoid content, individual phenolic compounds, antioxidant activities (1,1-diphenyl-2-picrylhydrazyl (DPPH), radical scavenging activity, FRAP, and chelating activity) were also determined. The results showed that ECPP possessed a strong ability to protect DNA from being damaged by hydroxyl radicals in both the site-specific system and the non-site-specific system. It also exhibited a cytoprotection effect in mouse lymphocytes against H₂O₂-induced DNA damage. These protective effects may be related to its high total phenolic content (17.65 ± 0.97 mg GAE/g), total flavonoid content (8.04 ± 0.97 mg rutin/g), strong free radical scavenging activity and considerable ferrous ion chelating ability (14.48 ± 0.21 mg Na₂EDTA/g).     

瑞舒伐他汀对自发性高血压大鼠心肌组织SOD、MDA、NO、ET的影响

目的：观察氧自由基损害和血管内皮功能失调与高血压发生的关系及瑞舒伐他汀干预的影响。方法将8只Wistar －Kyoto 大鼠（WKY）作为正常对照组;32只自发性高血压（SHR）大鼠,随机分为瑞舒伐他汀低剂量组3．125 mg／（kg· d）、瑞舒伐他汀中剂量组6．25 mg／（kg· d）、瑞舒伐他汀高剂量组12．5 mg／（kg· d）和SHR 对照组,每组8只。给药大鼠分别每日给予不同剂量瑞舒伐他汀＋1 mL蒸馏水灌胃;SHR 对照组给予相同容积的蒸馏水灌胃,测量血压。4周停药,3天后麻醉状态下提取心肌组织,用比色法检测SOD、MDA、NO 的水平,免疫组化法测定ET 的表达,PCR 法测定SODmRNA 的水平。结果自发性高血压大鼠SOD 活力、SODmRNA 表达、NO 含量下降,MDA 含量、ET －1的表达增强,与正常对照组比较,P ＜0．05。瑞舒伐他汀干预后上述指标均有改善（P ＜0．05）,且呈剂量相关性。瑞舒伐他汀干预后SHR 大鼠血压下降,但无剂量相关性。结论 SHR 大鼠存在氧化应激反应的增强,瑞舒伐他汀可通过降低氧化应激反应,改善血管内皮功能、降低血压。     

钩藤饮子合小青龙汤辨证治疗咳嗽变异性哮喘（风邪犯肺证）的效果及对外周血白三烯D4、C4及尿白三烯E4水平的影响

[目的] 探究钩藤饮子合小青龙汤辨证治疗咳嗽变异性哮喘（风邪犯肺证）的效果及对外周血白三烯D4（LTD4）、C4（LTC4）及尿白三烯E4（LTE4）水平的影响。[方法] 选取海口市人民医院100例咳嗽变异性哮喘患者为研究对象,按照简单随机法分为对照组和观察组,对照组（50例）给予孟鲁司特钠片和沙美特罗替卡松粉吸入剂治疗,观察组（50例）在对照组基础上加用钩藤饮子合小青龙汤治疗,比较治疗2个月后两组患者的临床疗效、中医症状积分改善情况、肺功能[第1秒用力呼气容积（FEV1）、呼气高峰流速（PEF）、用力肺活量（FVC）]、外周血炎症因子水平[LTD4、LTC4、LTE4、血清嗜酸性粒细胞（EOS）、免疫球蛋白（IgE）]、药物不良反应及治疗结束6个月内预后。[结果] 治疗2个月后,观察组疗效优于对照组（P<0.05）;两组中医症状积分降低（P<0.05）,且治疗后观察组中医症状积分低于对照组（P<0.05）;两组FEV1、PEF、FVC水平升高（P<0.05）,外周血LTD4、LTC4、LTE4、血清EOS、IgE水平降低（P<0.05）,且治疗后上述指标组间比较差异有统计学意义（P<0.05）;治疗期间,两组不良反应发生率比较差异无统计学意义（P>0.05）;治疗结束后6个月内随访,对照组有13例复发,复发率26.00%,观察组出现4例复发,复发率8.00%,组间比较差异有统计学意义（P<0.05）。[结论] 钩藤饮子合小青龙汤治疗咳嗽变异性哮喘（风邪犯肺证）临床有效、安全,可改善症状,提高肺功能,抑制炎症因子水平,且复发率较低。