Cerebellar thiol status and motor deficit after lactational exposure to methylmercury
Cerebellar thiol status and motor deficit after lactational exposure to methylmercury
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DOI：
10.1016/j.envres.2006.02.003
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发表时间：
2006-09-01
影响因子：
8.3
通讯作者：
Farina, Marcelo
中科院分区：
文献类型：
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作者：
Franco, Jeferson L.;Teixeira, Adriana;Farina, Marcelo
本研究探讨了甲基汞（甲基汞）暴露通过母乳对生化参数的巯基状态（谷胱甘肽（GSH）水平，谷胱甘肽过氧化物酶（GPx）和谷胱甘肽还原酶（GR）的活动）在乳鼠小脑的独家贡献。同样的生化参数也在母亲的小脑中进行了评估，这些母亲被提交给直接口服接触甲基汞（饮用水中10毫克/升）。关于小脑功能和运动活动之间的关系，还评估了哺乳期接触甲基汞的后代是否存在运动障碍的迹象。治疗后（断奶期），哺乳期暴露于甲基汞的幼鼠小脑中的汞含量比对照组的幼鼠高，并且在转棒装置中的运动性能显著受损。此外，与对照组的幼仔相比，这些幼仔小脑中的GSH水平降低。在母鼠，甲基汞显着增加小脑GSH的水平和小脑GR的活动。然而，这是没有观察到的幼崽。本研究表明：（1）哺乳期小鼠暴露于甲基汞会导致其后代的运动能力明显受损，这可能与小脑巯基状态下降有关;（2）仅在暴露于甲基汞的母鼠小脑中观察到的GSH水平和GR活性升高可能代表甲基汞对内源性GSH的氧化作用的代偿性病理生理反应。(c)2006年爱思唯尔公司All rights reserved.
This study examined the exclusive contribution of methylmercury (MeHg) exposure through maternal milk on biochemical parameters related to the thiol status (glutathione (GSH) levels, glutathione peroxidase (GPx) and glutathione reductase (GR) activities) in the cerebellums of suckling mice. The same biochemical parameters were also evaluated in the cerebellums of mothers, which were submitted to a direct oral exposure to MeHg (10 mg/L in drinking water). With regard to the relationship between cerebellar function and motor activity, the presence of signs of motor impairment was also evaluated in the offspring exposed to MeHg during lactation. After the treatment (at weaning period), the pups lactationally exposed to MeHg showed increased levels of mercury in the cerebellum compared to pups in the control group and a significant impairment in the motor performance in the rotarod apparatus. In addition, these pups showed decreased levels of GSH in the cerebellum compared to pups in the control group. In dams, MeHg significantly increased the levels of cerebellar GSH and the activities of cerebellar GR. However, this was not observed in pups. This study indicates that (1) the exposure of lactating mice to MeHg causes significant impairments in motor performance in the offspring which may be related to a decrease in the cerebellar thiol status and (2) the increased GSH levels and GR activity, observed only in the cerebellums of MeHgexposed dams, could represent compensatory pathophysiologic responses to the oxidative effects of MeHg toward endogenous GSH. (c) 2006 Elsevier Inc. All rights reserved.