Copper toxicity in gills of the teleost fish, Oreochromis niloticus: Effects in apoptosis induction and cell proliferation
Copper toxicity in gills of the teleost fish, Oreochromis niloticus: Effects in apoptosis induction and cell proliferation
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DOI：
10.1016/j.aquatox.2009.07.008
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发表时间：
2009-09-14
影响因子：
4.5
通讯作者：
Sousa, Mario
中科院分区：
文献类型：
--
作者：
Monteiro, Sandra Mariza;dos Santos, Nuno M. S.;Sousa, Mario
最近的体外研究表明，铜可以诱导细胞凋亡，触发caspase-3的激活，caspase-3是凋亡细胞死亡的中心效应因子。然而，铜诱导细胞凋亡的确切机制仍然不清楚，在尼罗罗非鱼中更是如此，到目前为止还没有caspase基因的报道。本研究旨在评价铜在体内诱导尼罗罗非鱼鳃细胞凋亡中的作用，同时有助于阐明铜诱导细胞凋亡的机制。对Caspase-3基因进行了部分测序，并用荧光定量聚合酶链式反应检测了L-1铜暴露后Caspase-3基因在体内的表达。用TUNEL法检测细胞凋亡率，用增殖细胞核抗原抗体鉴定细胞增殖。铜浓度不能诱导尼罗罗非鱼caspase-3基因表达上调。此外，在暴露于铜的鱼的鳃中，估计的凋亡细胞的相对体积并没有增加，这表明既没有诱导依赖于caspase-3的凋亡途径，也没有诱导非依赖于caspase的凋亡途径。另一方面，上皮增殖细胞体积密度的增加表明了一种浓度依赖的修复反应。(C)2009爱思唯尔B.V.保留所有权利。
Recent in vitro studies have demonstrated that copper may induce apoptosis triggering the activation of caspase-3, a central effector of apoptotic cell death. However, the precise mechanism of copper-induced apoptosis is still unclear, even less so in Oreochromis niloticus where no caspase genes have been reported so far. This study aimed to assess the in vivo role of copper in apoptosis induction on O. niloticus gill, simultaneously contributing to elucidate the mechanism of copper-induced apoptosis. Caspase-3 gene was partially sequenced and, after in vivo exposures to 40 and 400 mu g L-1 of copper, its mRNA expression was evaluated by real-time PCR. Apoptosis was also evaluated by TUNEL assay and cell proliferation identified using an antibody against proliferating cell nuclear antigen (PCNA). The copper concentrations used did not induce the upregulation of caspase-3 gene in O. niloticus gill. In addition, in the gills of fish exposed to copper there was no increase in the estimated relative volume of apoptotic cells, indicating that neither the caspase-3-dependent or caspase-independent apoptotic pathways were induced. On the other hand, the increase in the volumetric density of epithelial proliferating cells suggests a concentration-dependent repair response. (C) 2009 Elsevier B.V. All rights reserved.