Soares Felix Antunes, Fagundez Daiandra Almeida, Avila Daiana Silva
Departamento de Bioquimica e Biologia Molecular, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, 97105-900, Brazil.
Universidade Federal do Pampa, Uruguaiana, Rio Grande do Sul, 97508-000, Brazil.
Adv Neurobiol. 2017;18:355-383. doi: 10.1007/978-3-319-60189-2_18.
Metals are a component of a variety of ecosystems and organisms. They can generally be divided into essential and nonessential metals. The essential metals are involved in physiological processes once the deficiency of these metals has been associated with diseases. Although iron, manganese, copper, and zinc are important for life, it has been evidenced that they are also involved in neuronal damage in many neurodegenerative disorders. Nonessential metals, which are metals without physiological functions, are present in trace or higher levels in living organisms. Occupational, environmental, or deliberate exposures to lead, mercury, aluminum, and cadmium are clearly correlated with the increase of toxicity and varied kinds of pathological situations. Actually, the field of neurotoxicology needs to satisfy two opposing demands: the testing of a growing list of chemicals and resource limitations and ethical concerns associated with testing using traditional mammalian species. Toxicological assays using alternative animal models may relieve some of this pressure by allowing testing of more compounds while reducing expenses and using fewer mammals. The nervous system is by far the more complex system in C. elegans. Almost a third of their cells are neurons (302 neurons versus 959 cells in adult hermaphrodite). It initially underwent extensive development as a model organism in order to study the nervous system, and its neuronal lineage and the complete wiring diagram of its nervous system are stereotyped and fully described. The neurotransmission systems are phylogenetically conserved from nematodes to vertebrates, which allows for findings from C. elegans to be extrapolated and further confirmed in vertebrate systems. Different strains of C. elegans offer a new perspective on neurodegenerative processes. Some genes have been found to be related to neurodegeneration induced by metals. Studying these interactions may be an effective tool to slow neuronal loss and deterioration.
金属是各种生态系统和生物体的组成部分。它们通常可分为必需金属和非必需金属。一旦这些金属的缺乏与疾病相关联，必需金属就会参与生理过程。尽管铁、锰、铜和锌对生命很重要，但有证据表明它们也参与了许多神经退行性疾病中的神经元损伤。非必需金属是没有生理功能的金属，在生物体中以痕量或更高水平存在。职业性、环境性或故意接触铅、汞、铝和镉显然与毒性增加和各种病理情况相关。实际上，神经毒理学领域需要满足两个相互矛盾的需求：对越来越多的化学物质进行测试以及资源限制和与使用传统哺乳动物物种进行测试相关的伦理问题。使用替代动物模型的毒理学测定可以通过允许测试更多化合物、降低成本和减少哺乳动物使用量来减轻一些这种压力。神经系统是秀丽隐杆线虫中迄今为止更为复杂的系统。它们几乎三分之一的细胞是神经元（成年雌雄同体线虫中有302个神经元，而细胞总数为959个）。它最初作为一种模式生物经历了广泛的发展，以便研究神经系统，其神经元谱系和神经系统的完整接线图是定型的且已被充分描述。从线虫到脊椎动物，神经传递系统在系统发育上是保守的，这使得秀丽隐杆线虫的研究结果能够被外推并在脊椎动物系统中得到进一步证实。不同品系的秀丽隐杆线虫为神经退行性过程提供了新的视角。已经发现一些基因与金属诱导的神经退行性变有关。研究这些相互作用可能是减缓神经元损失和退化的有效工具。
