Effects of vitamin E on renal dysfunction in chronic cadmium-poisoned rats

Cadmium is a highly toxic metal that can be ingested or inhaled from a variety of industrial and dietary sources. The purpose of this study was to investigate the effects of vitamin E on renal dysfunction and blood pressure changes in chronic cadmium-poisoned rats. Sprague-Dawley rats weighing 100 +/- 10 g were randomly assigned to one control group and three cadmium-poisoned groups. Cadmium groups were assigned to dietary groups according to levels of vitamin E supplementation: vitamin E-free diet (Cd-0E group), 40 mg of vitamin E/kg of diet (Cd-40E group), and 400 mg of vitamin E/kg of diet (Cd-400E group). The animals were raised for 20 weeks, and cadmium was supplied in the drinking water at 50 ppm Cd(2+). The morphological changes observed by both light and electron microscopy revealed mitochondria and tubule epithelial cell edema in the Cd-0E group, yet this was alleviated with the highest level of vitamin E supplementation (Cd-400E group). The urinary beta(2)-microglobulin levels indicated that glomerular injury was higher in the Cd-poisoned groups than in the control group, but were lowered by vitamin E supplementation. Although the glomerular filtration rate (GFR) of the Cd-0E group was significantly lower than that of the control group, the vitamin E-supplemented groups exhibited a similar GFR to the control group, suggesting that vitamin E protected the kidney from functional damage. Angiotensin converting enzyme activity, and blood pressure, and heart rate were all significantly higher in the Cd-poisoned group, but each remained nearly normal with vitamin E supplementation. Accordingly, these results indicate that vitamin E supplementation in chronic cadmium-poisoned rats normalized renal dysfunction and blood pressure regulation.     

维生素E对双酚A暴露的发育期雄性小鼠生殖系统及抗氧化能力的影响

目的研究双酚A(BPA)暴露对雄性小鼠生殖系统及抗氧化能力的影响,以及大剂量补充维生素E对BPA作用的影响。方法 32只4～5周龄雄性昆明小鼠随机分为3组,分别为空白对照组(玉米油灌胃0.2ml/d,n=10),BPA组(每天给予BPA 0.5mg/kg BW灌胃,n=11)和维生素E干预组(每天给予BPA 0.5mg/kg BW和维生素E 150mg/kg BW灌胃,n=11)。干预3周后处死动物,测量血和各组织抗氧化活性,并检测生殖功能指标。结果 BPA组的睾丸湿重,BPA组和维生素E干预组的精囊湿重、精囊脏器系数和精子计数显著低于空白对照组(P<0.05或P<0.01);而维生素E干预组精囊脏器系数显著高于BPA组(P<0.05);BPA组和维生素E干预组的精子畸形率显著高于空白对照组(P<0.01);BPA组精子活动度显著低于空白对照组与维生素E干预组(P<0.05)。BPA组和维生素E干预组肝脏SOD活力显著高于空白对照组(P<0.05)。BPA组血清睾酮水平低于维生素E干预组和空白对照组,但差异无显著性。结论双酚A的短期暴露对雄性小鼠的生殖系统可能产生一定抑制作用,并显示出对实验动物抗氧化能力增强;短期补充维生素E对双酚A暴露所引起的生殖系统抑制可产生一定保护作用。     

Effects of omega 3 fatty acids and vitamin E on hormones involved in carbohydrate and lipid metabolism in men.

Forty healthy men were fed diets providing 40% of energy from fat and a minimum of 25 mg vitamin E for 28 wk. During the first 10 wk diets were supplemented with placebo, 15 g mixed fat/d. During the second 10 wk placebo was replaced by 15 g fish-oil concentrate/d. During the last 8 wk 200 mg vitamin E/d was added to fish oil. Compared with placebo, fish-oil feeding significantly increased plasma glucose and decreased triacylglycerol, insulin, glucagon, growth hormone, and somatomedin C. The changes in plasma cholesterol, cortisol, and dehydroepiandrosterone sulphate (DHEA-S) were not significant. Fish oil plus vitamin E further decreased insulin, growth hormone, and DHEA-S and reversed the effect of fish-oil on somatomedin C. The changes in glucose, glucagon, growth hormone, and cortisol were not significant. Thus, changes in plasma glucose and lipids caused by dietary fish oil alone and with fish oil plus vitamin E appear to be due to alterations in hormones involved in carbohydrate and lipid metabolism.     

维生素E和N-乙酰半胱氨酸对甲醛所致小鼠学习记忆能力改变的影响

目的探讨维生素E(VitE)和N-乙酰半胱氨酸(NAC)两种抗氧化剂对甲醛(FA)所致小鼠学习记忆能力损伤的保护作用。方法将34只清洁级ICR小鼠随机分为对照组(生理氯化钠,n=8)、FA组(15 mg/kg,n=9)、FA(15mg/kg) NAC(100 mg/kg)组(n=9)、FA(15 mg/kg) VitE(100 mg/kg)组(n=8)。每日给药1次,连续7 d。第8天开始用六臂放射状水迷宫检测小鼠的学习记忆能力,连续检测7 d。并检测谷胱甘肽(GSH)、丙二醛(MDA)。结果FA组小鼠早期兴奋后期则静卧少动,其余各组小鼠无此现象。体重增长在各组小鼠间比较,差异无统计学意义(P>0.05)。经重复测量资料方差分析,发现FA组小鼠学习期和记忆期潜伏时间延长,差异有统计学意义(F=5.479和2.953,P<0.01);但学习期和记忆期的小鼠错误次数差异无统计学意义(P>0.05);FA组的GSH含量高于对照组,差异有统计学意义(P<0.05)。两个干预组的MDA低于FA组,但差异无统计学意义(P>0.05)。结论抗氧化剂对FA致小鼠学习记忆能力损伤有保护作用。     

维生素E对移植器官慢性排斥反应的影响

目前 ,移植领域的一个重要方向就是诱导多机制起作用的免疫耐受 ,防治人体对同种异体器官的慢性排斥反应。作者列举了该方向在免疫因素和非免疫因素方面一些新的发现 ,总结了大剂量维生素E(VE)对免疫系统的调节作用 ,是通过Th/Ts比值的改变和不提高特异性抗体水平来实现的。同时 ,VE强大的抗氧化作用有助于减轻移植组织的氧化压力和血管损伤 ,展望了VE用于防治移植器官慢性排斥反应的意义以及存在问题。     

维生素E对二硫化碳致雄性大鼠睾丸组织脂质过氧化的拮抗作用

目的探讨二硫化碳(CS2)对雄性大鼠睾丸组织氧自由基及抗氧化水平的影响,同时观察维生素E(VE)对其的拮抗作用。方法取健康Wistar雄性大鼠36只随机分为6组,以不同浓度CS2(0、50、250、1250mgm3)静式吸入染毒,共10周,另设1250mgm3(CS2)加VE(250mgkg)组和单纯VE(250mgkg)组,VE拌入饲料中,染毒结束后,处死动物取出睾丸制备组织匀浆,分别测定各组SOD、MDA、GST、GSH、GSHpx、NO、总NOS和iNOS水平,同时检测VE对其的拮抗水平。结果睾丸组织中SOD活力下降,MDA含量上升,与对照组比较有显著差异(P<0.05);GSH含量、GST、GSHpx活力总体趋势下降,与对照组比较有显著差异(P<0.05或P<0.01);NO含量及总NOS、iNOS活力均下降,有随染毒浓度增加而降低的趋势,与对照组比较有显著差异(P<0.05或P<0.01)。但用VE干预后,SOD、GST、GSHpx、总NOS、iNOS活力均有不同程度上升,GSH、NO含量亦是如此,而MDA含量则下降。结论VE对CS2致睾丸组织脂质过氧化有拮抗作用。     

氧化应激在硫酸镍致小鼠睾丸损伤中的作用

目的从氧化应激角度,探讨镍对小鼠睾丸组织细胞损伤的机制.方法建立亚慢性毒性实验动物模型：硫酸镍0.8、2.0和5.0 mg/kg腹腔注射染毒,每日1次,连续30 d.制备睾丸组织匀浆,采用原子吸收分光光度法测定睾丸组织中Ni含量;酶法测定睾丸组织中超氧化物歧化酶（SOD）、乳酸脱氢酶（LDH）和一氧化氮合酶（NOS）活力;用分光光度法测乳酸（LD）总抗氧化能力（T-AOC）、还原型谷胱甘肽（GSH）、丙二醛（MDA）和一氧化氮（NO）的含量.结果硫酸镍可导致睾丸组织中Ni含量升高,抑制SOD和NOS活力,升高LDH活力,差异有统计学意义（P＜0.05）;引起T-AOC、GSH和NO含量降低,MDA和LD含量升高,差异有统计学意义（P＜0.05）.结论硫酸镍对小鼠睾丸损伤可能与Ni致睾丸细胞氧化应激效应增强以及抑制NOS活力,从而使一氧化氮的含量减少有关.     

亚慢性钐暴露对小鼠睾丸组织抗氧化能力的影响

目的 探讨亚慢性钐暴露对小鼠睾丸组织抗氧化能力的影响.方法 将50只初断乳的清洁级ICR雄性小鼠随机分成5组,分别为对照(蒸馏水)组和5、50、500、2000 mg/L硝酸钐染毒组,每组10只.采用自由饮水方式进行染毒,连续染毒90d.检测睾丸匀浆中氧化损伤指标超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、总抗氧化能力(T-AOC)活力和丙二醛(MDA)含量.结果 与对照组比较,2000 mg/L硝酸钐染毒组小鼠睾丸匀浆中SOD、GSH-Px活力以及500、2000 mg/L硝酸钐染毒组小鼠睾丸匀浆中T-AOC活力均明显下降,500、2000 mg/L硝酸钐染毒组小鼠睾丸匀浆中MDA含量明显上升,差异有统计学意义(P＜0.05).结论 亚慢性钐暴露对小鼠睾丸抗氧化能力具有一定的抑制作用.     

Effect of selenium-induced oxidative stress on the cell kinetics in testis and reproductive ability of male mice

OBJECTIVE: The present study evaluated the role of experimental oxidative stress (induced by feeding diets with different concentrations of selenium [Se], a trace nutrient and potent antioxidant) on male reproductive activity in mice. METHODS: To create different levels of oxidative stress in male mice, three diets with different levels of Se were fed to different groups for 8 wk. Mice in group 1 were fed a yeast-based diet, which is considered a Se-deficient diet (0.02 ppm). Mice in groups 2 and 3 were fed with an Se-deficient diet supplemented with 0.2 and 1 ppm Se as sodium selenite, respectively. RESULTS: After completion of the feeding schedule, a significant decrease in Se levels were observed in Se-deficient mice (group 1), whereas Se levels greatly increased in the Se-excess mice (group 3). Glutathione peroxidase activity was greatly decreased in the liver and testis in group 1, whereas glutathione-S-transferase activity was significantly increased in the testis. No significant change was found in activities of glutathione peroxidase and glutathione-S-transferase in group 3 compared with group 2. Cell kinetics showed a significant decrease in the number of pachytene spermatocytes and young and mature spermatids in group 1 compared with group 2. No appreciable change was observed in the germinal cell population in group 3. A significant decrease in sperm number was observed in group 1 compared with group 2. No change in these parameters was observed in group 3. The fertility status of mice in terms of percent fertility and litter size also exhibited a significant decrease in the reproductive ability of group 1. No change in these parameters was observed in group 3 compared with group 2. CONCLUSION: The present results clearly demonstrate the effect of oxidative stress generated by feeding different concentrations of Se on cell kinetics in the testis and, hence, its effect on the reproductive ability of male mice.     

Effects of vitamin E on reproductive protection in pregnant mice infected with pseudorabies virus (PRV) via regulating expression of Toll-like receptors (TLRs) and cytokine balance

Vitamin E supplement and pseudorabies virus (PRV) infection have a reciprocal role in influencing the maternal immune response, a key determinant of the success or failure of pregnancy. However, it remains unknown whether vitamin E supplement provides protection against PRV-induced failure of pregnancy. This study was therefore conducted to investigate the effect of dietary vitamin E level (0, 75, 375, 750 and 1,500 mg/kg) on the reproduction performance, immunity and expression of Toll-like receptors (TLRs) of PRV-challenged mice. The mortality and abortion rate of PRV-challenged mice decreased with the increase in vitamin E consumption. Overall, PBS-injected mice had a higher live embryo number and live litter size than PRV-challenged mice. Both live embryo number and live litter size of PRV-challenged mice increased with increasing vitamin E levels. Vitamin E supplement resulted in decreased concentration of serum IL-2 and IFN-γ, but increased concentration of serum IL-10. The concentration of serum IgG, IgA and IgM increased with increasing vitamin E levels. In the uterine and embryo mRNA abundance of TLR3, TLR7 and TLR9 was higher in PRV-challenged mice than that in PBS-injected mice fed on the same dosage of vitamin E. The mRNA abundance of embryonic TLR3, TLR7 and TLR9 in PRV-challenged mice decreased with increasing vitamin E levels. Collectively, vitamin E supplement may improve reproductive performance of PRV-challenged mice by attenuating PRV-induced negative effects on the cytokine profile, immunoglobulin synthesis and TLR expression.     

维生素C和维生素E对糖尿病大鼠非酶糖化和过氧化反应的影响

以链脲佐菌素腹腔注射ＳＤ大鼠建立糖尿病动物模型，在纯营养素饲料配方中补充维生素Ｃ和／或维生素Ｅ，喂饲周，观察单独或联合补充维生素Ｃ、维生素Ｅ对糖尿病非酶糖化及过氧化的干预作用。结果显示维生素Ｃ和Ｅ联合补充可显著减少糖尿病大鼠血红蛋白、低「密度脂蛋白及肾脏皮质的糖化终产物（ＡＧＥｓ）含量，同时显著降低脂质过氧化产物丙二醛（ＭＤＡ）水平，单独补充维生素Ｃ或维生素Ｅ能显著降低糖尿病鼠血清及肾脏ＭＤＡ含量     

Effects of vitamin E and selenium deficiencies on rat capillaries

Capillaries in the retina and rectus muscles of vitamin E and selenium deficient rats were examined by electron microscopy. In vitamin E deficient rats, retinal capillaries showed thickening of the basement membranes of the endothelial cells. On the other hand, capillaries in the muscles had thin basement membranes, and hemorrhages occurred due to the breakdown of endothelial cells. In selenium-deficient rats no significant abnormalities were seen in retinal or muscle capillaries. Although selenium has been considered to be similar to vitamin E as an antioxidant, the present study suggests that they are different. The effect of vitamin E on capillary basement membranes varies from tissue to tissue.     

Effects of chronic polychlorinated biphenyls exposure on reproductive success of white-footed mice (peromyscus leucopus)

Reproductive success was impaired in white-footed mice (Peromyscus leucopus) chronically exposed to food treated at a rate of 10 ppm (g/g) polychlorinated biphenyls (PCBs) (Aroclor® 1254). Mice in which PCBs exposure was initiated at adulthood (wild-caught and subsequently paired) and laboratory-raised mice paired and first exposed to PCBs-treated food at 16 weeks of age weaned significantly smaller numbers of young. Other parameters of reproductive success (interval between births, litter size at birth) were unaffected.Laboratory-raised white-footed mice paired and first exposed to PCBs-treated food at 12 weeks of age exhibited longer intervals between births, smaller litter sizes at birth, and smaller litter sizes at weaning.These results suggest that exposure to PCBs-contaminated natural foods can contribute to declines in natural populations of white-footed mice by reducing the number of young mice entering the breeding population.     

蒺藜皂苷对衰老小鼠睾丸生精功能影响

目的 探讨蒺藜皂苷对D-半乳糖所致衰老小鼠睾丸生精功能影响,为临床延缓衰老研究奠定实验基础.方法 健康昆明种小鼠40只,随机分为对照组、衰老模型组、蒺藜皂苷组和维生素E组,每组10只.经颈背部皮下注射5%D-半乳糖,连续6周,建立小鼠亚急性衰老模型.蒺藜皂苷和维生素E组分别灌胃给予蒺藜皂苷和维生素E,对照组和衰老模型组给予等体积纯净水.检测全血中过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)活力;附睾精子密度、精子活率和活精子百分率.结果 蒺藜皂苷组小鼠全血CAT及GSH-Px活力分别为(24.28±1.53)U/mgHb和(205.65±10.94)酶活力单位,明显高于衰老模型组小鼠(P<0.01),蒺藜皂苷组小鼠附睾精子密度、精子活率和活精子百分率分别为(6.34±0.24)×10⁵个/mL、(73.28±1.60)%和(76.61±2.19)%,与衰老模型组比较,明显提高,差异有统计学意义(P<0.01).结论 蒺藜皂苷可通过抗氧化作用改善衰老小鼠生精功能.     

己烯雌酚对小鼠睾丸引带细胞雌激素受体的影响

目的研究雌激素受体ERα和ERβ在培养的小鼠睾丸引带细胞的表达情况,并探讨己烯雌酚(diethylstilbestrol,DES)对其表达水平的影响。方法将培养的传代小鼠睾丸引带细胞随机分为空白对照组、溶剂对照组[1μl/ml二甲基亚砜(DMSO组)]和4个实验组(终浓度分别为0.01、0.1、1、10μg/ml DES)。分别采用免疫细胞化学及Western blot方法检测雌激素受体ERα和ERβ的表达。结果免疫细胞化学显示ERα仅表达于睾丸引带细胞的细胞核,ERβ表达于细胞核及细胞质。免疫印迹显示ERα及ERβ均存在于小鼠睾丸引带细胞,且不同程度地受到DES作用剂量及作用时间的影响,以ERα表达较为明显。随着作用时间的延长,在相对低剂量组(0.01、0.1μg/ml DES组)中,ERα呈倒"U"形表达,ERβ呈"U"形表达;在相对高剂量组(10μg/ml DES组)中,除ERα高表达于12 h外,其他时间段ERα和ERβ的表达均受到明显抑制。结论 ER存在于睾丸引带细胞,不同剂量DES对睾丸引带的影响较为复杂。DES可能通过类似内源性雌激素的形式与ER结合,由ER介导引起睾丸引带组织结构和功能改变,从而影响雄性生殖系统发育。