Dai Anqi, Liu Xudong, Chen Yinuo, Wang Yougang, Qi Haomin, Zeng Yan, Li Jinquan
Hubei Provincial Clinical Research Center for Alzheimer's Disease, Brain Science and Advanced Technology Institute, School of Medicine, Wuhan University of Science and Technology, Wuhan, China.
Department of Food Science and Engineering, Moutai Institute, Renhuai 564507, China.
Environ Int. 2025 May;199:109501. doi: 10.1016/j.envint.2025.109501. Epub 2025 Apr 25.
Ozone (O) and nanoplastics (NPs) are pervasive environmental pollutants that frequently co-occur in our heavily industrialized era. While it has been documented that exposure to O or NPs individually has neurotoxic effects, studies investigating their combined impact and the hazardous mechanisms resulting from co-exposure are limited. In this study, we established a mouse model co-exposure to polystyrene nanoparticles (PS-NPs) and O, focusing on the prefrontal cortex (PFC), a brain region crucial for cognition and emotion. We examined the effects of O and PS-NPs on behavioral changes related to learning, memory, and anxiety, employing transcriptome sequencing alongside molecular and histopathological methods. Our findings indicate that combined exposure to O and PS-NPs disrupts the integrity of the blood-brain barrier, reducing Claudin 5 expression and leading to increased accumulation of PS-NPs in the PFC. Transcriptome sequencing demonstrated the involvement of the p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway and oxidative stress in the pathological changes observed in the PFC. Through immunohistochemical and immunofluorescence analysis, we observed enhanced microglial activation, which correlates with increased production of inflammatory factors. Additionally, western blot and immunofluorescence co-labeling analyses revealed elevated expression levels of GSDMD-N, caspase-1, IL-1β, and IL-18 proteins, which are associated with neuronal pyroptosis. Finally, immunofluorescence co-labeling confirmed that the activation of the p38 MAPK pathway in neurons is involved in co-exposure-induced pyroptosis. Meanwhile, N-Acetylcysteine (NAC), a common antioxidant, can alleviate neuroinflammation and neuronal pyroptosis in the PFC, and it rescued the cognitive deficits and anxiety-like behaviors observed in the co-exposed mice. Our study illustrates that co-exposure to O and NPs can aggravate damage to the blood-brain barrier and elevate oxidative stress levels in the PFC, thereby increasing the occurrence of neuroinflammation and may mediate neuronal pyroptosis through activation of the p38 MAPK pathway, ultimately contributing to neurobehavioral toxicity.
臭氧（O₃）和纳米塑料（NPs）是普遍存在的环境污染物，在我们这个高度工业化的时代经常同时出现。虽然已有文献记载，单独接触臭氧或纳米塑料会产生神经毒性作用，但研究它们的联合影响以及共同暴露所导致的有害机制的研究却很有限。在本研究中，我们建立了一个同时暴露于聚苯乙烯纳米颗粒（PS-NPs）和臭氧的小鼠模型，重点关注前额叶皮质（PFC），这是一个对认知和情绪至关重要的脑区。我们采用转录组测序以及分子和组织病理学方法，研究了臭氧和PS-NPs对与学习、记忆和焦虑相关的行为变化的影响。我们的研究结果表明，同时暴露于臭氧和PS-NPs会破坏血脑屏障的完整性，降低Claudin 5的表达，并导致PS-NPs在前额叶皮质中的积累增加。转录组测序表明，p38丝裂原活化蛋白激酶（pʹ38 MAPK）信号通路和氧化应激参与了前额叶皮质中观察到的病理变化。通过免疫组织化学和免疫荧光分析，我们观察到小胶质细胞活化增强，这与炎症因子产生增加相关。此外，蛋白质免疫印迹和免疫荧光共标记分析显示，与神经元焦亡相关蛋白GSDMD-N、半胱天冬酶-1、白细胞介素-1β和白细胞介素-18的表达水平升高。最后，免疫荧光共标记证实，神经元中p38 MAPK通路的激活参与了共同暴露诱导的焦亡。同时，常见的抗氧化剂N-乙酰半胱氨酸（NAC）可以减轻前额叶皮质中的神经炎症和神经元焦亡，并挽救共同暴露小鼠中观察到的认知缺陷和焦虑样行为。我们的研究表明，同时暴露于臭氧和纳米塑料会加重血脑屏障的损伤，提高前额叶皮质中的氧化应激水平，从而增加神经炎症的发生，并可能通过激活p38 MAPK通路介导神经元焦亡，最终导致神经行为毒性。
