Fu Chih-Wei, Horng Jiun-Lin, Tong Sok-Keng, Cherng Bor-Wei, Liao Bo-Kai, Lin Li-Yih, Chou Ming-Yi
Department of Life Science, National Taiwan University, Taipei, Taiwan.
Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.
J Hazard Mater. 2021 Feb 5;403:124031. doi: 10.1016/j.jhazmat.2020.124031. Epub 2020 Sep 18.
Silver and silver nanoparticles are used in several consumer products, particularly sterilizing agents. Ag released from the particles causes physiological damages of aquatic organisms. However, the effects of silver on neural and behavioral functions of fish remain unclear. Here, we used zebrafish as a model to investigate the impacts of silver on social, learning and memory behaviors in teleost. Adult zebrafish showed mortality rates of 12.875% and 100% on 72 h exposure to 30 and ≥ 50 ppb of silver nitrate, respectively. Silver accumulation in the brain increased on exposure to 10 and 30 ppb of AgNO. The physical fitness of the zebrafish, measured by novel tank diving test and swimming performance, decreased after 72 h incubation in 30 ppb of AgNO. Exposure to 10 ppb of AgNO impaired social preference, social recognition, learning, and memory, but did not affect anxiety level, aggressiveness, and shoaling behavior. In situ hybridization of c-fos mRNA showed that AgNO treatment decreased neural activity in the brain areas crucial for learning, memory, and social behaviors, including the medial and dorsal zones of the dorsal telencephalic area. In conclusion, 72 h exposure to AgNO in a sublethal level impaired learning and social behaviors, indicating neurotoxicity in adult zebrafish.
银和银纳米颗粒被用于多种消费产品中，尤其是消毒剂。从颗粒中释放出的银会对水生生物造成生理损害。然而，银对鱼类神经和行为功能的影响仍不清楚。在此，我们以斑马鱼为模型，研究银对硬骨鱼社会、学习和记忆行为的影响。成年斑马鱼在暴露于30和≥50 ppb硝酸银72小时后，死亡率分别为12.875%和100%。暴露于10和30 ppb硝酸银时，大脑中的银积累量增加。通过新水箱潜水试验和游泳表现衡量的斑马鱼身体素质，在30 ppb硝酸银中孵育72小时后下降。暴露于10 ppb硝酸银会损害社会偏好、社会识别、学习和记忆，但不影响焦虑水平、攻击性和群居行为。c-fos mRNA的原位杂交显示，硝酸银处理降低了对学习、记忆和社会行为至关重要的脑区的神经活动，包括背侧端脑区域的内侧和背侧区域。总之，72小时暴露于亚致死水平的硝酸银会损害学习和社会行为，表明成年斑马鱼存在神经毒性。
