College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China.
Acta Biochim Biophys Sin (Shanghai). 2017 Dec 1;49(12):1083-1091. doi: 10.1093/abbs/gmx111.
β-Cypermethrin (β-CYP), one of most important pyrethroids, is widely used to control insects, and has been detected in organisms, including human. Pyrethroids have been shown to pose neurotoxicity, hepatotoxicity, endocrine disruption and reproductive risks in mammals. However, research in immunotoxicity of pyrethroids, especially their metabolites, is limited. A common metabolite of pyrethroids is 3-phenoxybenzoic acid (3-PBA) in mammals. Thus, in this study, we evaluated the immunotoxicity of β-CYP and 3-PBA in mouse macrophages, RAW 264.7 cells. MTT assays showed that both β-CYP and 3-PBA reduced cell viability in a concentration- and time-dependent manner. Flow cytometry with Annexin-V/PI staining demonstrated that both β-CYP and 3-PBA induced RAW 264.7 cell apoptosis. Furthermore, our results also showed that N-acetylcysteine partially blocked β-CYP- and 3-PBA-induced cytotoxicity and apoptosis. Intrinsic apoptotic pathway was stimulated by both β-CYP and 3-PBA exposure. In addition, we found that β-CYP and 3-PBA inhibited mRNA levels of pro-inflammatory cytokines with or without LPS stimulation. Phagocytosis assay showed that both β-CYP and 3-PBA inhibited phagocytic ability of macrophages. Moreover, it was also found that both β-CYP and 3-PBA increased reactive oxygen species (ROS) levels in RAW 264.7 cells. Accordingly, both β-CYP and 3-PBA were found to regulate the mRNA levels of oxidative stress-related genes in RAW 264.7 cells. Taken together, the results obtained in this study demonstrated that β-CYP and 3-PBA may have immunotoxic effect on macrophages and that elevated ROS may underlie the mechanism. The present study will help to understand the health risks caused by β-CYP and other pyrethroids.
β-氯氰菊酯（β-CYP）是最重要的拟除虫菊酯之一，被广泛用于控制昆虫，已在包括人类在内的生物体中被检测到。拟除虫菊酯已被证明对哺乳动物具有神经毒性、肝毒性、内分泌干扰和生殖风险。然而，拟除虫菊酯的免疫毒性，特别是其代谢物的免疫毒性研究还很有限。哺乳动物中拟除虫菊酯的一种常见代谢物是 3-苯氧基苯甲酸（3-PBA）。因此，在本研究中，我们评估了β-CYP 和 3-PBA 在小鼠巨噬细胞 RAW 264.7 细胞中的免疫毒性。MTT 检测结果表明，β-CYP 和 3-PBA 均呈浓度和时间依赖性降低细胞活力。用 Annexin-V/PI 染色的流式细胞术显示，β-CYP 和 3-PBA 均诱导 RAW 264.7 细胞凋亡。此外，我们的结果还表明，N-乙酰半胱氨酸部分阻断了β-CYP 和 3-PBA 诱导的细胞毒性和凋亡。β-CYP 和 3-PBA 暴露均刺激内在凋亡途径。此外，我们发现，β-CYP 和 3-PBA 抑制了 LPS 刺激或不刺激时促炎细胞因子的 mRNA 水平。吞噬作用检测表明，β-CYP 和 3-PBA 均抑制了巨噬细胞的吞噬能力。此外，还发现β-CYP 和 3-PBA 增加了 RAW 264.7 细胞中的活性氧（ROS）水平。相应地，β-CYP 和 3-PBA 均被发现调节 RAW 264.7 细胞中氧化应激相关基因的 mRNA 水平。综上所述，本研究结果表明，β-CYP 和 3-PBA 可能对巨噬细胞具有免疫毒性，而升高的 ROS 可能是其作用机制。本研究将有助于了解β-CYP 和其他拟除虫菊酯引起的健康风险。
