饮水铅暴露对大鼠脑组织 APE1 表达的影响及与氧化应激的关系研究

目的 探讨饮水铅暴露对大鼠大脑皮质、 小脑、 海马组织中脱嘌呤脱嘧啶核酸内切酶 1（APE1）表达的影响及其与氧化应激的关系。方法 40 只刚断乳雄性 SD 大鼠按体质量随机区组法均分为 5 组, 对照组自由饮用去离子水, 4 个铅暴露组分别饮用 100、 200、 400 和 800 mg/L 醋酸铅溶液, 连续染毒 60 d 后, 取大脑皮质、 小脑和海马组织, 测定各组的超氧化物歧化酶 （SOD） 活力、 过氧化氢 （H2O2） 水平和丙二醛 （MDA） 含量, 蛋白印迹法检测 APE1 蛋白在各组织中的表达。结果 铅暴露后, 大脑皮质、 小脑、 海马中 APE1 蛋白表达水平均低于对照组, 且随染铅剂量的升高呈逐渐下降趋势（P＜0.05）; 随着染铅剂量的升高, 大脑皮质、 小脑和海马中的 SOD 活力基本呈下降趋势; 而 H2O2及 MDA 含量随染铅剂量的升高基本呈逐渐升高趋势, 大脑皮质、 小脑和海马组织的 APE1 蛋白表达水平与其 SOD 活力呈正相关（r 分别为 0.619、 0.380、 0.375, P < 0.05） ,而与 H2O2水平和 MDA 含量呈负相关（r 分别为-0.472、 -0.535、 -0.436, -0.514、 -0.486、 -0.316, P < 0.05）。结论 饮水铅暴露可导致大鼠脑组织 APE1 蛋白表达水平改变,且此种改变与铅所致的氧化应激有关。     

DNA修复基因XRCC1在胃癌中的表达及意义

目的探讨DNA修复基因XRCC1在胃癌中的表达及意义。方法用免疫组化方法检测胃癌组织、远癌组织及肠上皮化生组织中XRCC1的蛋白表达。结果 3组XRCC1在胃癌组织中的表达水平间,差异均有统计学意义(P<0.05)。结论 XRCC1在胃癌组织中表达异常,提示其在胃癌发生过程中可能起重要作用。     

XRCC1基因多态性与宫颈鳞癌放疗敏感性的关系

【摘要】目的 探讨XRCC1基因Arg194Trp、Arg399Gln单核苷酸多态性（SNP）与外生型宫颈鳞状细胞癌放疗敏感性的关系。方法 采用错配扩增聚合酶链式反应（MAMA-PCR）方法检测73例外生型宫颈鳞状细胞癌患者血液标本的XRCC1 Arg194Trp、Arg399Gln两个SNP的基因型频率分布,进一步分析其与宫颈癌放疗敏感性的关系。结果 XRCC1基因Arg194Trp、Arg399Gln基因型完全缓解组和部分缓解组分布情况均无统计学差异（P>0.05）。结论XRCC1基因Arg194Trp、Arg399Gln SNP与外生型宫颈鳞状细胞癌放疗敏感性无相关性。     

XRCC1与晚期非小细胞肺癌含铂类药物化疗疗效的关系

目的 探讨X线修复交叉互补基因1 (XRCC1)与接受含铂方案化疗的晚期非小细胞肺癌(NSCLC)患者的近期疗效的关系.方法 经病理确诊的晚期NSCLC患者62例,接受含铂方案化疗至少2个周期后评价疗效.采用TaqMan探针FQ-PCR法和直接测序法对患者外周血XRCC1第399位密码子进行多态性分析,分析各基因型与晚期NSCLC患者近期疗效及不良反应的的相关性.结果 XRCC1 399至少携带一个Gln等位基因携带者的疗效不如Arg等位基因携带者(14.81％vs.42.86％)(P＜0.05).XRCC1不同基因型与化疗不良反应无明显相关性.结论 XRCC1 399多态性与NSCLC患者对铂类药物化疗的敏感性相关.     

XRCC1基因多态性与晚期非小细胞肺癌铂类化疗敏感性关系的Meta分析

目的：探讨 X 射线交错互补修复基因1（XRCC1）多态性与晚期非小细胞肺癌（NSCLC）患者对铂类药物化疗敏感性的关系。方法检索PubMed、中国知网、维普等数据库,收集有关晚期NSCLC患者的XRCC1基因399及194位点基因多态性与铂类化疗敏感性关系的文献。以化疗后客观疗效作为评估指标,采用Revman 5．1软件对纳入文献进行异质性检验,计算合并后的优势比（OR）及其95％可信区间（CI）,并进行敏感性分析及发表偏倚评估。结果共计13篇文献入选,包括1490例晚期NSCLC患者。与野生基因型相比,XRCC1基因399及194位点至少携带1个突变基因的NSCLC患者对铂类化疗敏感性增加。此外,中国地区XRCC1基因399位点至少携带1个突变基因的NSCLC患者对铂类化疗敏感性亦高于野生基因型。结论 XRCC1基因399及194位点基因多态性影响NSCLC患者对铂类化疗的敏感性;进行基因型检测有利于NSCLC患者的个体化治疗。     

XRCC1基因rs25487位点多态性与男性不育相关性的meta分析

目的 评价X射线交叉互补修复1(XRCC1)基因rs25487位点多态性与男性不育的相关性.方法 计算机检索PubMed、万方和中国知网等数据库,检索时限为建库至2021年3月31日.检索XRCC1基因rs25487位点多态性与男性不育的相关文献,提取相关数据,使用Stata11.0软件进行meta分析.结果 共纳入8...     

X线修复交叉互补基因1缺陷细胞株的建立及其蛋白的表达

目的 运用载体介导的RNA干扰技术靶向抑制人X线修复交叉互补基因1(XRCC1)在支气管上皮细胞中的表达,为研究人XRCC1蛋白在环境化学污染物所致DNA损伤修复中的功能和机制作准备.方法 利用分子克隆技术构建含pU6启动子的XRCC1 RNA干扰特异性绿色荧光蛋白C1载体重组子"pEGFP-C1-U6-dsRNA";以脂质体法将载体重组子转染人支气管上皮细胞,同时以空白细胞和空载体转染细胞作对照;在经G418筛选后,以荧光显微成像技术观察细胞的转染效果,以蛋白印迹法分析转染后细胞中的XRCC1蛋白表达情况.结果 在转染重组子的细胞中,XRCC1蛋白的表达明显下调,仅相当于正常细胞的38.2%.结论 人支气管上皮细胞人X线修复交叉互补基因1的靶向抑制成功.     

XRCC1 rs25487基因多态性对非小细胞肺癌患者铂类联合方案预后的影响

目的探讨X线修复交错互补基因1 (XRCC1) rs25487基因多态性对接受铂类药物联合方案化疗的非小细胞肺癌(NSCLC)患者预后的影响。方法回顾性分析2014年1月至2018年9月在徐州医科大学附属医院行含铂类联合化疗方案治疗的NSCLC患者248例,收集患者的临床基本信息。采用PCRRFLP法进行基因分型,分析XRCC1 rs25487的基因型和等位基因分布差异,观察各基因型对铂类药物的疗效差异。采用Log-Rank检验、 Kaplan-Meier生存曲线和Cox风险回归模型评估各基因型患者间的预后差异。结果与GG型患者相比,AG和AA型患者近期疗效改善明显(P=0.041),但远期疗效无显著差异(P>0.05)。与携带等位基因G患者相比,携带等位基因A患者中位无进展生存期和中位总生存期显著缩短(均P=0.019);携带等位基因A患者疾病进展风险增加(HR=1.567, 95%CI:1.070～2.294, P=0.021),死亡风险增加(HR=1.572, 95%CI:1.067～2.317, P=0.022)。结论 XRCC1 rs25487位点多态性是江苏苏北地区汉族NSCLC患者预后不佳的重要因素,等位基因A是引起预后不佳的风险因子。     

大肠癌BRCA-1、ERCC1mRNA表达水平对铂类化疗预后的影响分析

目的 探讨大肠癌乳腺癌易感蛋白1(BRCA-1)、核苷酸切除修复交叉互补基因1信使核糖核酸(ERCC1mRNA)的表达水平对铂类化疗预后的影响.方法 58例大肠癌患者,均采用FOLFOX化疗方案治疗.对患者手术标本进行BRCA-1、ERCC1mRNA表达水平检测.分析大肠癌组织中BRCA-1、ERCC1mRNA表达情况...     

白藜芦醇对慢性帕金森病6-OHDA模型大鼠iNOS mRNA及HO-1 mRNA表达的影响

目的观察白藜芦醇能否通过抑制诱导型一氧化氮合成酶(iNOS)mRNA及血红素加氧酶-1(HO-1)mRNA的表达对慢性帕金森病(PD)6-羟基多巴胺(6-OHDA)模型大鼠产生保护效应。方法经筛选无旋转行为的SD大鼠60只,随机选20只分为假手术组及正常给药组(白藜芦醇20 mg.kg-1.d-1);应用6-OHDA纹状体内注射制作PD模型大鼠40只,随机分为模型组和白藜芦醇10、20和40 mg.kg-1.d-1组,每日灌胃给药1次,连续10 wk。电镜下观察黑质神经元超微结构的改变,real-time PCR法检测大鼠黑质部iNOS mRNA及HO-1 mRNA的表达。结果电镜结果显示白藜芦醇治疗组能改善6-OHDA导致的大鼠黑质多巴胺能神经元超微结构的损伤。与模型组比较,白藜芦醇治疗组iNOS mRNA、HO-1 mRNA的表达均明显降低(P<0.01)。结论白藜芦醇对慢性帕金森病6-OHDA模型大鼠具有保护作用,其机制与抑制iNOS mRNA和HO-1 mRNA的表达有关。     

Effects of lead exposure on the expression of phospholipid hydroperoxidase glutathione peroxidase mRNA in the rat brain.

Oxidative damage associated with lead in the brain has been proposed as a possible mechanism of lead toxicity. Of the many antioxidant enzymes, phospholipid hydroperoxidase glutathione peroxidase (PHGPx) is known to protect cells from lipid peroxide-mediated damage by catalyzing lipid peroxide reduction. In this study, the effects of lead on the activity and expression of PHGPx mRNA were investigated in the brains of rats exposed to lead for 8 weeks. Male Sprague-Dawley rats (3 week old, n = 40) were randomly divided into four groups of 10 and treated with four different concentrations of lead in drinking water: a low dose (0.1% lead acetate), a medium dose (0.3% lead acetate), and a high dose (1.0% lead acetate), and a control group (0% lead acetate). We compared the four groups in terms of body and brain weight, lead concentrations in the brain and blood, and the activities of superoxide dismutase (SOD), gluthatione peroxidase (GPx), and PHGPx mRNA in the brain. Phospholipid hydroperoxidase glutathione peroxidase was found to have a dominant role in lead exposure. We also performed in situ hybridization of PHGPx mRNA in the brain to identity PHGPx mRNA active sites. We found that the level of PHGPx mRNA in brain increased in the medium- and low-dose groups, but decreased in the high-dose group versus the non-lead-treated control group. These results suggest that lead exposure increases the expression of PHGPx mRNA in the low- and medium-dose groups without inducing structural changes, and that the reduced expression of PHGPx mRNA in the high-dose group was associated with structural damage. An In situ hybridization study showed that PHGPx mRNA in the brain is expressed mainly in the white matter of the cerebral hemisphere and in the Purkinje cells of the cerebellar hemispheres; these sites are known to be the vulnerable to lead toxicity.     

硫化氢对局灶性脑缺血大鼠脑组织氧化应激的影响

目的：观察硫化氢（H2 S）对局灶性脑缺血大鼠脑组织氧化应激的影响。方法40只健康雄性 SD 大鼠,随机分为假手术（Sham）组、缺血模型（Ischemia）组、H2 S 低剂量（L-NaHS）组、H2 S 中剂量（M-NaHS）组和 H2 S 高剂量（H-NaHS）组。线栓法复制大鼠大脑中动脉闭塞模型。H2 S 低、中、高剂量组大鼠于缺血3 h 时分别腹腔注射0.7 mg/ kg、1.4 mg/ kg 和2.8 mg/ kg 的 NaHS,Sham 组和 Ischemia 组注射等容量的0.9%氯化钠溶液。5组大鼠均于缺血24 h 时断头取脑,测定脑组织中丙二醛（ MDA）的含量、超氧化物歧化酶（ SOD）的活性和谷胱甘肽过氧化物酶（GSH-PX）的活性;透射电镜观察脑组织的病理变化。结果与 Sham 组比较,Ischemia 组大鼠脑组织 SOD、GSH-PX 活性明显降低（ P ﹤0.01）,MDA 含量明显升高（ P ﹤0.01）;电镜观察显示神经元水肿,线粒体膜肿胀、线粒体嵴断裂甚至消失,线粒体大量空泡化,细胞器的数量减少;与 Ischemia 组比较,M-NaHS、H-NaHS 组大鼠脑组织中 SOD、GSH-PX活性明显升高（ P ﹤0.05）,MDA 含量明显降低（ P ﹤0.05）;电镜观察可见神经元轻度水肿,线粒体部分肿胀、内外膜结构清晰、部分嵴断裂消失,细胞器数量增多,脑缺血损伤程度明显减轻。结论 H2 S 可减轻大鼠局灶性脑缺血损伤,其机制与提高大鼠的抗氧化应激能力有关。     

葛根素在减轻创伤性脑损伤氧化应激反应中的作用

目的：探究葛根素是否能有效减轻创伤性脑损伤（TBI）中的氧化应激反应。方法选择成年雄性 SD大鼠60只构建 TBI 模型并随机平分为模型组,假手术组及葛根素给药组（给药组）,每组20只。检测3组大鼠在不同时间点氧化应激相关指标[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）、丙二醛（MDA）]活性及含量变化。结果氧化应激相关指标检测中,给药组与模型组比较,其中第3、7天 SOD、CAT 活性以及 MDA、NO 含量与同时间点模型组比较差异有统计学意义（ P ＜0．05）。用药组与模型组比较,均能不同程度升高GSH 含量及 GSH－Px 活性（ P ＜0．05）,其中给药组第3天及第7天 GSH 含量及 GSH－Px 活性较同时间点模型组比较差异有统计学意义（ P ＜0．05）。结论根据对不同氧化应激指标检测所得结果可以看出葛根素可有效减轻创伤性脑损伤所带来的氧化应激损伤。     

Analysis of neuroglobin mRNA expression in rat brain due to arsenite-induced oxidative stress

Arsenic (As) in drinking water is a toxicant causing several health problems including nervous system disturbance. Neuroglobin (Ngb) is a tissue globin in nervous system playing protective role against oxidative stress in many injuries. This study was to investigate how long arsenite exposure (sodium arsenite 7.5 mg/kg/day) could induce oxidative stress in blood and brain of rats and to determine whether Ngb expression in rat brain changed due to oxidative stress. Results showed that superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in serum and brain homogenates and reactive oxygen species (ROS) generation in red blood cells (RBCs) did not change in the rats exposed to arsenite for 8 weeks. In the rats exposed to arsenite for 16 weeks, SOD activity decreased (serum: P < 0.05; brain homogenates: P < 0.01) and MDA level increased (P < 0.01) in serum and brain homogenates; ROS production increased (P < 0.01) in RBC. When oxidative stress occurred, Ngb mRNA expression did not change in whole brain, cerebral cortex, midbrain, and hippocampus; however, Ngb mRNA expression increased significantly (P < 0.05) in cerebellum compared to the control group. This study suggests that arsenite exposure for 16 weeks can lead to oxidative stress of blood and brain of rats. Ngb may play a protective role incerebellum when oxidative stress occurs due to arsenite exposure. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012.     

Influence of lead acetate on glutathione and its related enzymes in different regions of rat brain

This study is intended to determine the effect of lead acetate on glutathione and its associated enzymes of rat brain. Wistar male rats were treated with lead acetate (500 ppm) through drinking water for a period of 8 weeks and parallel controls were maintained. They were sacrificed at the first, fourth and eighth week to isolate whole brains, which were separated into cerebellum, hippocampus, frontal cortex and brain stem. The data indicate enhanced (P < 0.05) glutathione peroxidase (G‐Px) activity at most of the intervals for cerebellum, frontal cortex and brain stem, suggesting conversion of GSH to GSSG, while the hippocampus showed decreased levels. In contrast, glutathione reductase (GR) decreased significantly (P < 0.05) in cerebellum, frontal cortex and brain stem at all intervals except the fourth week in frontal cortex and brain stem. Hippocampus exhibited a gradual and significant (P < 0.05) increase in GR activity. Glutathione‐S‐transferase (GSTase) activity increased with exposure time in all four brain tissues, showing protection against lead acetate toxicity. The GSH and GSSG levels correlated well with the activities of GPx, GR and GSTase in all four regions of the brain. Overall the results indicate that lead acetate affects glutathione‐related enzymes differentially and these changes can be attributed to differences in tissue susceptibility. Copyright © 2009 John Wiley & Sons, Ltd.     

依达拉奉对大鼠XRCC1和细胞凋亡的影响

目的研究大鼠全脑缺血/再灌注不同时点海马CA1区神经元细胞凋亡与DNA修复蛋白XRCC1的变化及相互关系,探讨依达拉奉对神经元细胞凋亡与DNA修复蛋白表达的影响。方法 SD大鼠108只,随机平均分为假手术组(SH组)、缺血再灌注组(IR组)和依达拉奉干预组(ED组)。采用四血管阻塞法建立大鼠全脑缺血再灌注模型,干预组经腹腔注射依达拉奉。分别于再灌注后2、6、12、24、48、72 h处死大鼠,提取脑海马部组织。原位末端标记法(TUNEL)检测细胞凋亡;免疫组织化学方法检测DNA修复蛋白XRCC1的表达。结果 TUNEL法:SH组凋亡率较低,IR组凋亡率于缺血再灌注6 h开始明显增多,48 h凋亡率达到最高。IR组与SH组凋亡率比较,差异有统计学意义(P<0.01)。ED组在6 h后各时点凋亡率较IR组降低(P<0.01)。免疫组化方法:SH组XRCC1在各时点表达较为明显;IR组XRCC1表达在缺血再灌注2 h开始下降,6 h后下降明显,持续到72 h,与SH组比较差异有统计学意义(P<0.01);ED组XRCC1表达量降低不明显,各时点与IR组比较差异有统计学意义(P<0.01)。结论依达拉奉通过减缓XRCC1表达的下降,促进DNA损伤修复,从而阻止锥体细胞凋亡,进而起到脑保护作用。     

Lack of reversal of oxidative damage in renal tissues of lead acetate‐treated rats

Removal of lead from the environment of man or otherwise, the movement of man from lead‐contaminated areas has been employed as a means of abatement of the toxic effects of lead. Whether toxic effects in already‐exposed individuals subside after lead withdrawal remains unanswered. To understand the reversibility of nephrotoxicity induced by lead acetate, male Wistar rats were orally exposed to 0.25, 0.5, and 1.0 mg/mL of lead acetate for 6 weeks. Activities of glutathione‐s‐transferase, catalase (CAT), superoxide dismutase (SOD) and the concentrations of hydrogen peroxide (H₂O₂), and malondialdehyde increased significantly (p < 0.05) in a dose‐dependent manner, whereas reduced glutathione (GSH) level and glutathione peroxidase activity were significantly reduced. The pattern of alterations in most of the oxidative stress and antioxidant parameters remained similar in rats from the withdrawal period, although CAT and SOD activities reduced, in contrast to their elevation during the exposure period. Serum creatinine levels were significantly elevated in both exposure and withdrawal experiments whereas serum blood urea nitrogen levels were not significantly different from the control in both exposure and withdrawal periods. The histological damage observed include multifocal areas of inflammation, disseminated tubular necrosis, and fatty infiltration of the kidney tubules both at exposure and withdrawal periods. The results suggest that lead acetate‐induced nephrotoxicity by induction of oxidative stress and disruption of antioxidant. The aforementioned alterations were not reversed in the rats left to recover within the time course of study. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1235–1243, 2015.     

Ameliorative effects of Bacopa monniera on lead-induced oxidative stress in different regions of rat brain

Abstract

Bacopa monniera is a rejuvenating herb for brain cells enhancing learning and cognitive ability. In the present investigation, the ameliorative effects of Bacopa monniera were examined against lead-induced oxidative stress in different regions of rat brain. Male rats were divided into five groups: control (1000?ppm sodium acetate) and exposed (1000?ppm lead acetate) for 4 weeks; DMSA (Meso-2,3-Dimercaptosuccinic acid)-treated (90?mg/kg body weight/day); Bacopa monniera-treated (BM) (10?mg/kg body weight/day) and a combination of BM?+?DMSA for seven consecutive days after 4 weeks of lead exposure. After treatment, the whole brain was isolated by sacrificing rats and four regions were separated namely cerebellum, hippocampus, frontal cortex and brain stem. Results indicated a significant (p?<?0.05) increase in reactive oxygen species (ROS), lipid peroxidation products (LPP) and total protein carbonyl content (TPCC) in association with tissue metal content in all the four regions of brain for exposed group compared with their respective controls. However, the lead-induced ROS, LPP, TPCC and tissue metal content were lowered on treatment with Bacopa monniera, almost reaching the control group values in all the above brain regions compared to DMSA and a combination therapy. Results suggest that Bacopa monniera can mitigate the lead induced-oxidative stress tissue specifically by pharmacologic interventions which encompass both chelation as well as antioxidant functions.     

Nephrotoxic effects of lead nitrate exposure in diabetic and nondiabetic rats: Involvement of oxidative stress and the protective role of sodium selenite

Heavy metals are known to be toxic to organisms. The present study was undertaken to evaluate the protective effect of sodium selenite against lead nitrate (LN)‐induced nephrotoxicity in diabetic and nondiabetic rats. Animals were divided into eight groups where the first was served as a control, whereas the remaining groups were treated with sodium selenite (1 mg/kg b.w.), LN (22.5 mg/kg b.w.) and a combination of LN and sodium selenite and diabetic forms of these groups. Changes in antioxidant enzyme activities, malondialdehide levels, serum urea, uric acid, creatinine levels, body, and kidney weights and histopathological changes were determined after 28 days. LN caused severe histopathological changes, increment in urea, uric acid, creatinine, and MDA levels, also decreasing in antioxidant enzyme activities, body, and kidney weights. In sodium selenite + LN group, we observed the protective effect of sodium selenite on examining parameters. Also diabetes caused alterations on these parameters compared with nondiabetic animals. We found that sodium selenite did not show protective effect on diabetes caused damages. As a result, LN caused nephrotoxicity and sodium selenite alleviated this toxicity but sodium selenite did not protect kidneys against diabetes mediated toxicity. Also, LN caused more harmfull effects in diabetic groups compared with nondiabetic groups. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1229–1240, 2016.