Institut de Radioprotection et de Sûreté Nucléaire, Pôle Santé Environnement, Service de recherche sur les effets biologiques et sanitaires des rayonnements ionisants, Avenue de la Division Leclerc, Fontenay aux Roses, France.
Institut de Radioprotection et de Sûreté Nucléaire, Pôle Sûreté Nucléaire, Service du Confinement et de l'Aérodispersion des Polluants, Gif-sur-YvetteCedex, France.
Inhal Toxicol. 2024 Apr;36(4):261-274. doi: 10.1080/08958378.2024.2349895. Epub 2024 Jun 5.
Our work is focused on tungsten, considered as an emerging contaminant. Its environmental dispersion is partly due to mining and military activities. Exposure scenario can also be occupational, in areas such as the hard metal industry and specific nuclear facilities. Our study investigated the cerebral effects induced by the inhalation of tungsten particles.
Inhalation exposure campaigns were carried out at two different concentrations (5 and 80 mg/m) in single and repeated modes (4 consecutive days) in adult rats within a nose-only inhalation chamber. Processes involved in brain toxicity were investigated 24 h after exposure.
Site-specific effects in terms of neuroanatomy and concentration-dependent changes in specific cellular actors were observed. Results obtained in the olfactory bulb suggest a potential early effect on the survival of microglial cells. Depending on the mode of exposure, these cells showed a decrease in density accompanied by an increase in an apoptotic marker. An abnormal phenotype of the nuclei of mature neurons, suggesting neuronal suffering, was also observed in the frontal cortex, and can be linked to the involvement of oxidative stress. The differential effects observed according to exposure patterns could involve two components: local (brain-specific) and/or systemic. Indeed, tungsten, in addition to being found in the lungs and kidneys, was present in the brain of animals exposed to the high concentration.
Our data question the perceived innocuity of tungsten relative to other metals and raise hypotheses regarding possible adaptive or neurotoxic mechanisms that could ultimately alter neuronal integrity.
我们的工作重点是钨，这是一种新兴污染物。它在环境中的分散部分是由于采矿和军事活动造成的。暴露情况也可能是职业性的，例如在硬金属工业和特定核设施中。我们的研究调查了吸入钨颗粒引起的大脑效应。
在单剂量和重复剂量（连续 4 天）下，在单一鼻腔吸入室中，用成年大鼠在两种不同浓度（5 和 80mg/m）下进行吸入暴露实验。在暴露后 24 小时，研究了与脑毒性相关的过程。
观察到特定部位的神经解剖学效应和特定细胞因子的浓度依赖性变化。在嗅球中获得的结果表明，微胶质细胞的存活可能受到潜在的早期影响。根据暴露方式的不同，这些细胞的密度降低，同时凋亡标志物增加。在额叶皮质中还观察到成熟神经元核的异常表型，提示神经元受损，这可能与氧化应激的参与有关。根据暴露模式观察到的差异效应可能涉及两个成分：局部（大脑特异性）和/或全身。事实上，除了在肺部和肾脏中发现钨外，在暴露于高浓度的动物的大脑中也发现了钨。
我们的数据质疑了相对于其他金属，钨被认为是无害的观点，并提出了关于可能的适应性或神经毒性机制的假设，这些机制最终可能改变神经元的完整性。
