硒对氟致大鼠肝脏损伤的保护作用

目的探讨硒对氟致大鼠肝脏损伤的保护作用,探寻硒的最佳作用剂量及可能的作用靶点。方法将240只健康初断乳清洁级SD雄性大鼠随机分成8组,分别为溶剂对照(自来水,含氟量0.2 mg/L,含硒量1μg/L)组,氟(50 mg/L)单独染毒组,低(0.375 mg/L)、中(0.75 mg/L)、高(1.5 mg/L)浓度硒单独染毒组和低(0.375 mg/L)、中(0.75 mg/L)、高(1.5 mg/L)浓度硒+氟(50 mg/L)联合染毒组,每组30只。采用自由饮水方式进行染毒,连续染毒6个月。实验期间,大鼠进食标准饲料(氟含量0.2 mg/kg,硒含量为0.1～0.2 mg/kg)。染毒结束后,测定肝脏中谷胱甘肽过氧化物酶(GSH-Px)、总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)活力及丙二醛(MDA)含量及核转录因子κB(nuclear factor kappa B,NF-κB)表达水平。并观察氟中毒的一般症状和肝脏的病理学损伤。结果氟单独染毒组大鼠氟斑牙症状明显。与溶剂对照组相比,氟单独染毒组大鼠肝脏中GSH-Px、SOD活力降低,MDA含量升高,差异均有统计学意义(P0.05);高浓度硒单独染毒组SOD活力降低,差异均有统计学意义(P0.05)。与氟单独染毒组相比,高浓度硒+氟联合染毒组大鼠肝脏中GSH-Px活力上升,差异均有统计学意义(P0.05);高浓度硒+氟联合染毒组MDA含量下降,差异均有统计学意义(P0.05)。各染毒组大鼠肝脏中T-AOC活力间比较,差异无统计学意义。与溶剂对照组相比,氟单独染毒组和低浓度硒+氟联合染毒组大鼠肝组织中NF-κB表达水平升高,差异均有统计学意义(P0.05)。与氟单独染毒组相比,中浓度硒+氟联合染毒组和高浓度硒+氟联合染毒组大鼠肝组织中NF-κB表达水平有所降低,但差异无统计学意义。病理学结果显示,氟+硒联合染毒组大鼠肝细胞变性坏死程度明显减轻,且肝细胞变性坏死程度随着硒染毒浓度的升高而呈下降趋势。结论 1.5 mg/L是在本实验条件下硒对氟致肝脏损伤的最佳保护作用剂量,NF-κB可能是硒拮抗氟中毒的药物靶点。     

内毒素致大鼠肝组织氧化应激作用

[目的]探讨内毒素腹腔注射染毒对大鼠肝组织抗氧化酶的影响。[方法]采用腹腔注射技术,以脂多糖（LPS）对Wister大鼠进行染毒,染毒浓度分别为0.01、0.05、0.10、1.00mg/kg,对肝组织匀浆上清液中的超氧化物歧化酶（SOD）、Cu,Zn-SOD酶、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GSH-PX）活性以及谷胱甘肽（GSH）和丙二醛（MDA）含量进行测定。[结果]与对照组相比,染毒浓度分别为0.01、0.05和0.10mg/kg时,SOD酶活性变化无统计学差异（P〉0.05）;染毒浓度为1.00mg/kg时,有明显降低（P〈0.01）。与对照组相比,Cu,Zn-SOD酶活性随着染毒浓度的增大,呈现先升后降的趋势,浓度达0.05mg/kg时,升高具有统计学意义（P〈0.01）。与对照组相比,CAT酶活性和MDA含量的变化呈现先降后升的趋势,二者下降的最低点分别为0.05mg/kg和0.01mg/kg;GSH含量和GSH-PX活性均呈现先增后减的趋势,染毒浓度为0.05mg/kg时,二者的增高具有统计学意义（P〈0.01）。[结论]低浓度的LPS可致大鼠肝组织产生适应性反应;高浓度的LPS可引起大鼠肝组织抗氧化能力降低,提示高浓度LPS对大鼠肝的毒作用可能与诱发体内产生过量自由基有关。     

煤烟颗粒提取物对大鼠肺细胞的氧化 性损伤作用

目的：通过加入抗氧化剂N－乙酰半胱氨酸,作为实验干预手段。方法：观察煤烟对大鼠肺Ⅱ型细胞生长和DNA交联形成作用的影响。结果：与对照组相比,分别加入10、30mmol/L N－N乙酰半胱氨酸后的实验组细胞毒性有所下降, 从而间接地证实了氧化性损伤的存在;同时,N－乙酰半胱氨酸还可以降低煤烟经细胞染毒所致的DNA交联作用 。结论：煤烟可能是经过细胞代谢活化后产生的某些代谢产物而导致细胞的氧化性损伤。     

煤烟对大鼠肺细胞氧化性损伤作用途径的探讨

目的：探讨煤烟导致肺Ⅱ型细胞氧化性损伤的途径，方法：通过对加入抗氧化剂N－乙酰半胱氨酸、维生素E、维生素C和甘露醇作为实验干预手段，采用MTT法观察其对煤烟所致大鼠肺Ⅱ型细胞毒性的影响，结果：与对照组相比，加入10mmol/L N-乙酰半胱氨酸，维生素E，维生素C后的实验组细胞毒性有所下降，而甘露醇没有观察到类似的作用。结论：煤烟可以通过产生氧自由基或脂质过氧化物等多种途径对机体造成氧化性损伤。     

槲皮素对氧化应激大鼠肝细胞的保护作用

目的研究大鼠肝细胞对槲皮素的吸收以及吸收后对氧化应激损伤的作用。方法用高效液相色谱法（HPLC）测定原代培养的大鼠肝细胞对槲皮素的吸收。于培养液中加入过氧化氢诱导肝细胞氧化应激，观察槲皮素预处理后，氧化应激肝细胞乳酸脱氢酶（LDH）释放量、培养液总抗氧化能力（T-AOC）、细胞匀浆脂质过氧化终产物丙二醛（MDA）含量以及细胞凋亡率的变化。结果大鼠肝细胞对槲皮素有一定量的吸收，24小时达到高峰。过氧化氢可导致大鼠肝细胞损伤，培养液中LDH活性增加、T-AOC增强，细胞匀浆的MDA含量增加，细胞凋亡率增高。槲皮素预处理能减少氧化应激肝细胞LDH的释放，进一步增强T-AOC，降低MDA含量，并降低细胞凋亡率。结论大鼠肝细胞对槲皮素有一定量的吸收，槲皮素预处理对氧化应激肝细胞有一定的保护作用。     

煤烟致大鼠肺细胞氧化应激损伤的机制探讨

目的：探讨煤烟导致细胞体系氧化应激损伤的机制。方法：以Ｎ－乙酰半胱氨酸（ＮＡＣ）和甘露醇等不同作用位点的抗氧化剂作为实验干预手段，采用ＭＴＴ比色法和溴乙锭荧光法观察煤烟所致细胞毒性和肺细胞ＤＮＡ交联形成作用。结果Ｎ－乙酰半胱氨酸（ＮＡ）可以有效地降低煤烟气致的细胞毒性和细胞ＤＮＡ交联形成作用；而甘露醇却没有观察到上述作用。结论煤烟在细胞内经代谢活化后产生的某些代谢产物可以降低氏内谷胱甘肽含量，引起     

Sub-acute Deltamethrin and Fluoride Toxicity Induced Hepatic Oxidative Stress and Biochemical Alterations in Rats

The current study investigated the effects of deltamethrin, fluoride (F^?) and their combination on the hepatic oxidative stress and consequent alterations in blood biochemical markers of hepatic damage in rats. Significant hepatic oxidative stress and hepatic damage were observed in the toxicant exposed groups. These changes were higher in the deltamethrin-F^? co-exposure treatment group, depicting a positive interaction between the two chemicals.     

亚硒酸钠和N-乙酰半胱氨酸对锰致大鼠氧化损伤的影响

目的探讨亚硒酸钠(Na2SeO3)和N-乙酰半胱氨酸(NAC)对锰致大鼠氧化损伤的影响,为阐明锰中毒的发病机制和防治提供依据。方法Wistar大鼠32只,随机分为4组,分别为对照组、单纯染锰组、Na2SeO3干预组和NAC干预组。对照组大鼠腹腔注射生理盐水,其余各组腹腔注射150μmol/kgMnCl2溶液。腹腔注射后2h,对照组和单纯染锰组大鼠隔日皮下注射生理盐水,Na2SeO3干预组隔日皮下注射10μmol/kg Na2SeO3,NAC干预组隔日皮下注射1 mmol/kg NAC。每周染锰5次,1次/d,染毒4周。共计染锰20次,Na2SeO3和NAC干预各10次。测定肝、脑和肾组织还原型谷胱甘肽(GSH)、丙二醛(MDA)的含量和谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)的活力。结果与对照组比较,染锰大鼠肝、脑和肾组织MDA含量显著升高,肝肾组织GSH含量降低。Na2SeO3和NAC干预均使脑和肾组织MDA含量显著降低。Na2SeO3干预组大鼠肾GSH含量显著增加,肝GSH-Px和SOD活力降低。NAC干预组大鼠脑SOD活力显著降低。结论锰可使大鼠产生氧化损伤,Na2SeO3和NAC对锰致大鼠氧化损伤有一定的拮抗作用。     

褪黑素对饮水氟染毒大鼠脑组织氧化应激的影响

目的研究不同浓度饮水氟染毒对大鼠脑氧化应激状态的影响及褪黑素(MEL)的干预作用。方法将清洁级初断乳Wistar大鼠34只随机分为5组,分别为对照组(蒸馏水,8只),60、120mg/L氟单独染毒组(各7只),60mg/L氟+5mg/kg褪黑素联合染毒组和120mg/L氟+5mg/kg褪黑素联合染毒组(各6只)。各组大鼠饮用相应浓度的氟化钠溶液;从第7周开始腹腔注射褪黑素溶液,连续染毒10周。染毒结束后,取脑组织测定氟含量和谷胱甘肽(GSH)、超氧化物歧化酶(SOD)、丙二醛(MDA)水平以及单纯氟染毒组大鼠血清褪黑素水平。结果与对照组比较,120mg/L氟单独染毒组以及60mg/L氟+5mg/kg褪黑素联合染毒组和120mg/L氟+5mg/kg褪黑素联合染毒组大鼠脑组织中氟含量均较高,差异有统计学意义(P0.01)。氟单独染毒各组之间比较,GSH、SOD、MDA含量差异无统计学意义。与相同浓度氟单纯染毒组比较,60mg/L氟+5mg/kgMEL联合染毒组大鼠脑组织中GSH含量和SOD活力均较高,但差异无统计学意义;120mg/L氟+5mg/kgMEL联合染毒组大鼠脑组织中GSH含量较高,SOD活力较低,差异均无统计学意义。各组大鼠脑组织中MDA含量间比较,差异无统计学意义。与对照组比较,60mg/L氟单独染毒组大鼠脑组织中褪黑素浓度略有升高,120mg/L氟单独染毒组大鼠脑组织中褪黑素浓度有下降趋势,但差异均无统计学意义(P0.05)。结论氟能透过血脑屏障在脑中蓄积,产生一定程度的氧化损伤,小剂量的褪黑素干预未能见到明显的抗氧化作用。     

Perfluorooctanoic Acid Affects Mouse Brain and Liver Tissue Through Oxidative Stress

The aim of this study was to investigate oxidative stress induced by perfluorooctanoic acid (PFOA) in the brain and liver tissues of Balb/c mice as well as protective effects of taurine and coenzyme Q₁₀ (CoQ₁₀) in both organs. For this purpose, animals were treated with PFOA (15 and 30 mg/kg) orally and their lipid peroxidation, total glutathione levels (GSH), and antioxidant enzyme activities measured and both tissues analysed for histopathological changes. Our results showed a dose-dependent decrease in body weight and increase in relative brain and liver weights, PFOA-induced lipid peroxidation and reduced glutathione peroxidase (GPx) activity in the brain tissue, and changes in GSH levels, GPx, superoxide dismutase (Cu-Zn SOD), and catalase (CAT) activities in the liver tissue. Pre-treatment with taurine or CoQ₁₀ provided protection against PFOA-induced Cu-Zn SOD reduction in the liver tissue. Our findings evidence the depleting effect of PFOA on antioxidative systems and confirm that PFOA exerts its (neuro)toxicity through oxidative stress, but further research is needed to identify the exact toxicity mechanisms, especially in the brain.Key words: body weight, CAT, CoQ₁₀, GPx, GSH, hepatotoxicity, in vivo, neurotoxicity, oxidative damage, PFOA, relative organ weight, SOD, taurine     

葡萄籽原花青素对NaF致雄性小鼠肝脏氧化损伤的拮抗作用

[目的]观察葡萄籽原花青素(GSPE)对氟化钠(NaF)致雄性小鼠肝脏组织氧化损伤的拮抗作用. [方法]将40只健康性成熟昆明种雄性小鼠随机分为4组:对照组(0mg/kg)、NaF组(20 mg/kg)、GSPE组(200 mg/kg)及NaF+GSPE组[NaF(20 mg/kg)+GSPE(200 mg/kg)],每组10只动物.灌胃染毒,每天1次,连续染毒5周.颈椎脱臼处死,采集肝脏组织样本,计算肝脏脏器系数,检测肝脏组织中谷丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)和超氧化物歧化酶(SOD)活性,谷胱甘肽(GSH)和丙二醛(MDA)含量以及总抗氧化能力(T-AOC)水平. [结果]各组肝脏脏器系数组间比较,差异有统计学意义(P＜0.05); NaF组高于对照组(P＜0.05),(NaF+GSPE)组低于NaF组(P＜0.05).各组AST、ALT含量组间比较,差异有统计学意义(均P＜0.05);NaF组和(NaF+GSPE)组高于对照组(P＜0.05),GSPE组和(NaF+GSPE)组低于NaF组(P＜0.05).各组GSH、SOD、MDA和T-AOC含量组间比较,差异有统计学意义(均P＜0.05);与对照组相比,NaF组和(NaF+GSPE)组小鼠肝脏中GSH、SOD和T-AOC含量较低(P＜0.05),MDA含量较高(P＜0.05);与NaF组相比,GSPE组和(NaF+GSPE)组GSH、SOD和T-AOC含量较高(P＜0.05),MDA含量较低(P＜0.05).析因分析显示:NaF与GSPE对AST、ALT、SOD活力、MDA含量,T-AOC水平存在拮抗作用. [结论]GSPE对NaF致雄性小鼠肝脏氧化损伤具有拮抗作用.     

牛磺酸拮抗氯化镉致肝细胞氧化损伤的保护作用

目的观察牛磺酸拮抗氯化镉致大鼠肝细胞氧化损伤的保护作用。方法实验分5组:①阴性对照组;②氯化镉组:分别加入终浓度为10、20、40、100μmol/L的氯化镉;③同时处理组:终浓度为100 mmol/L的牛磺酸与氯化镉10、20、40、100μmol/L同时加入;④后处理组:先加入终浓度为10、20、40、100μmol/L的氯化镉,45min后加入100 mmol/L的牛磺酸;⑤预处理组:先加入终浓度为100 mmol/L的牛磺酸,45 min后加入10、20、40、100μmol/L的氯化镉。所有的处理组均培养2 h。结果①肝细胞中10、20、40、100μmol/L的氯化镉组GSH-Px酶活性明显低于阴性对照组;随着镉浓度增加,GSH-Px酶活性下降呈一定的剂量-效应关系。②预先处理组(65.26±14μmol/L)及同时处理组(49.65±1.54μmol/L)细胞GSH-Px酶活性明显升高,与相应的氯化镉组(27.11±1.09μmol/L)比较有显著性差异(P<0.05)。③当后处理组镉浓度达到40～100μmol/L时,细胞内SOD活性显著降低(23.08±1.49 U/ml),与相应的氯化镉组...     

Docosahexaenoic Acid Abundance in the Brain: A biodevice to Combat Oxidative Stress

Abstract

Docosahexaenoic acid (DHA) (22:6) is a polyunsaturated fatty acid of the n?3 series which is believed to be a molecular target for lipid peroxides (LPO) formation. Its ubiquitous nature in the nervous tissue renders it particularly vulnerable to oxidative stress, which is high in brain during normal activity because of high oxygen consumption and generation of reactive oxygen species (ROS). Under steady state conditions potentially harmful ROS and LPO are maintained at low levels due to a strong antioxidant defense mechanism, which involves several enzymes and low molecular weight reducing compounds. The present review emphasizes a paradox: a discrepancy between the expected high oxidability of the DHA molecule due to its high degree of unsaturation and certain experimental results which would indicate no change or even decreased lipid peroxidation when brain tissue is supplied or enriched with DHA. The following is a critical review of the experimental data relating DHA levels in the brain to lipid peroxidation and oxidative damage there. A neuroprotective role for DHA, possibly in association with the vinyl ether (VE) linkage of plasmalogens (pPLs) in combating free radicals is proposed.     

Protective Effect of Pistacia lentiscus Oil Against Bleomycin-Induced Lung Fibrosis and Oxidative Stress in Rat

We aimed in the present study to investigate the protective effect of Pistacia lentiscus oil against bleomycin-induced lung fibrosis as well as the involvement of oxidative stress in such protection. In this respect, adult male Wistar rats were used and divided into three groups of twenty each: control (NaCl, 0.9%), bleomycin, and bleomycin (4 mg/kg b.w.) + P. lentiscus oil (3 g/kg, b.w.). Animals were pretreated for 30 days before the induction of fibrosis by bleomycin and 1 wk after the induction of fibrosis. The oil principal compounds detected by gas chromatography analysis are: Linoleic and palmitic acids (70.6 and 24.7%, respectively). Our data demonstrated that P. lentiscus oil protected against bleomycin-induced fibrosis as evidenced by TGFβ immunostaining increase in lungs fibrocytes as well as inflammatory infiltrate. We also showed that acute bleomycin-induced fibrosis was accompanied by an oxidative stress in lung tissue as assessed by an increase of lipid peroxidation as well as antioxidant enzyme activities depletion such as superoxide dismutase (SOD) and catalase (CAT). More importantly, P. lentiscus oil treatment reversed all bleomycin-induced oxidative stress parameters disturbances. In conclusion, we suggest that P. lentiscus oil had potent protective effects against bleomycin-induced fibrosis due in part to its antioxidant properties.     

Protective Effect of Resveratrol on Biomarkers of Oxidative Stress Induced by Iron/Ascorbate in Mouse Spermatozoa

Resveratrol (RVT) is a polyphenolic compound found mainly in the grape and attributed with various pharmacological properties, among them their antioxidant activity. In the present study, we assess the antioxidant activity of resveratrol on oxidative damage induced by ferrous iron/ascorbate (100 µM/150 µM) in sperm of CD1⁺ mice. We evaluated several parameters in spermatozoa treated with or without resveratrol: (i) sperm quality analysis; (ii) mitochondrial transmembrane potential (Δψ_m); (iii) ROS generation; (iv) superoxide dismutase (SOD) activity; (v) glutathione peroxidase (GPX) activity; (vi) lipid peroxidation; (vii) and in vitro fertilization (IVF) capability. Spermatozoa treated with RVT (15 µg/mL) before ferrous iron/ascorbate treatment exhibited: a significant increase in motility (8-fold), a significant increase in viability (2-fold), a significant increase in Δψ_m (1.15-fold), accompanied with a significant decrease in the generation of ROS (4.96-fold), a significant decrease in GPX activity (1.32-fold), and a significant decrease in lipid peroxidation concentration (10.29-fold) relative to spermatozoa treated with ferrous iron/ascorbate; however, no changes in SOD activity were observed. Finally, spermatozoa treated with RVT before ferrous iron/ascorbate treatment showed a significant increase in oocyte fertilization (1.2-fold), relative to spermatozoa treated with ferrous iron/ascorbate. These results suggest that RVT possesses antioxidant properties that may prevent the deleterious effects produced by oxidative damage on spermatozoa, resulting in the maintenance of fertility.     

Neuroprotective Effect of Maltol Against Oxidative Stress in Brain of Mice Challenged with Kainic Acid

Abstract

The neuroprotective effect of maltol on oxidative damage in the brain of mice challenged with kainic acid was examined. Male ICR mice, 6-8 weeks of age, were administered orally with maltol (50 or 100 mg/kg) for 5 consecutive days. Thirty minutes after the final administration, the animals were challenged s.c. with kainic acid (50 mg/kg), and neurobehavioral activities were monitored. In addition, biomarkers of oxidative stress and neuronal loss in hippocampus for the biochemical and morphological evaluations were analyzed 2 days after the kainic acid challenge. During 5-day treatment with maltol, the body weight gain was not significantly different from that of vehicle-treated control animals. Administration of kainic acid alone induced severe epileptiform seizures, causing a lethality of approximately 50%, and injuries of pyramidals cells in hippocampus of mice survived the challenge. Kainic acid exposure also resulted in marked decreases in total glutathione level and glutathione peroxidase activity, and an increase in thiobarbituric acid-reactive substances (TBARS) value in brain tissues. In comparison, coadministration with maltol (100 mg/kg) remarkably attenuated the neurobehavioral signs and neuronal loss in hippocampus, leading to a decrease in mortality of animals to 12.5% (p<0.05), although maltol at a dose of 50 mg/kg failed to show any remarkable protection. In addition, the changes in glutathione and TBARS values and glutathione peroxidase activity induced by kainic acid were restored to control levels by pretreatment with maltol (100 mg/kg). On the basis of these results, maltol is suggested to be a functional agent to prevent the oxidative damage in the brain of mice.     

葡萄籽原花青素对香烟致晶状体氧化性损伤的保护作用

<正>许多流行病学研究揭示,吸烟对于晶状体核混浊白内障形成有密切关系[1]。香烟烟雾中含有大量自由基和金属离子,可与组织细胞内的多种生物分子作用,造成结构和功能的损伤[2]。葡萄籽原花青素(grapeseeds proanthocyanidins GSP)具有极强的抗氧化作用,本实验采取活体模拟吸烟环境,造成损伤模型,同时给予葡萄籽原花青素干预,探讨其对晶状体氧化性损伤的保护作用,为白内障防治提供依据。