Department of Biology, York University, Toronto, ON M3J 1P3, Canada.
Department of Biology, York University, Toronto, ON M3J 1P3, Canada.
Sci Total Environ. 2021 May 1;767:144329. doi: 10.1016/j.scitotenv.2020.144329. Epub 2020 Dec 25.
As an essential micronutrient, selenium (Se) exerts its biological function as a catalytic entity in a variety of enzymes. From a toxicological perspective, however, Se can become extremely toxic at concentrations slightly above its nutritional levels. Over the last few decades, there has been a growing level of concern worldwide regarding the adverse effects of both inorganic and organic Se compounds on a broad spectrum of neurological functions. A wealth of evidence has shown that exposure to excess Se may compromise the normal functioning of various key proteins, neurotransmitter systems (the glutamatergic, dopaminergic, serotonergic, and cholinergic systems), and signaling molecules involved in the control and regulation of cognitive, behavioral, and neuroendocrine functions. Elevated Se exposure has also been suspected to be a risk factor for the development of several neurodegenerative and neuropsychiatric diseases. Nonetheless, despite the various deleterious effects of excess Se on the central nervous system (CNS), Se neurotoxicity and negative behavioral outcomes are still disregarded at the expense of its beneficial health effects. This review focuses on the current state of knowledge regarding the neurobehavioral effects of Se and discusses its potential mode of action on different aspects of the central and peripheral nervous systems. This review also provides a brief history of Se discovery and uses, its physicochemical properties, biological roles in the CNS, environmental occurrence, and toxicity. We also review potential links between exposure to different forms of Se compounds and aberrant neurobehavioral functions in humans and animals, and identify key knowledge gaps and hypotheses for future research.
作为一种必需的微量元素，硒（Se）以多种酶的催化实体形式发挥其生物学功能。然而，从毒理学的角度来看，硒在其营养水平略高的浓度下可能变得极具毒性。在过去的几十年中，全世界对无机和有机硒化合物对广泛的神经功能的不良影响的关注程度不断增加。大量证据表明，暴露于过量的硒可能会损害各种关键蛋白质、神经递质系统（谷氨酸能、多巴胺能、血清素能和胆碱能系统）以及参与认知、行为和神经内分泌功能的控制和调节的信号分子的正常功能。过量的硒暴露也被怀疑是几种神经退行性和神经精神疾病发展的一个危险因素。尽管过量的硒对中枢神经系统（CNS）有各种有害影响，但仍忽视了硒的神经毒性和负面行为后果，而忽视了其有益的健康影响。本综述重点介绍了关于硒的神经行为影响的最新知识，并讨论了其对中枢和外周神经系统不同方面的潜在作用模式。本综述还提供了硒的发现和用途的简史、其在中枢神经系统中的物理化学性质、生物学作用、环境发生和毒性。我们还回顾了接触不同形式的硒化合物与人类和动物异常神经行为功能之间的潜在联系，并确定了未来研究的关键知识空白和假设。
