Katiyar Parul, Banerjee Somesh, Nathani Sandip, Roy Partha
Molecular Endocrinology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
Curr Res Toxicol. 2022 May 6;3:100072. doi: 10.1016/j.crtox.2022.100072. eCollection 2022.
Triclosan (TCS) is widely used in cosmetics and healthcare industry as a broad-spectrum antibacterial agent. The lipophilic property and persistent nature of TCS has led to severe health issues. In the present study, we have evaluated the neuroinflammatory effect of TCS on mouse Neuro-2a cells. Initial investigation confirmed a dose-dependent loss in viability and morphology of cells in presence of TCS. The transcription and translation studies confirmed a downregulation in the expression of autophagy markers in Neuro-2a cells. The confocal microscopy study revealed that the abrogated autophagy in TCS-treated cells occurred due to loss in the autophagy flux and prevention in the lipidation of autophagosome bilayer. The fluorescence microscopy also confirmed a loss in the formation of autophagolysosomes in neuronal cells with increasing TCS concentrations. TCS treatment resulted in loss of mitochondrial integrity in cells as evidenced by a decrease in mitochondrial membrane potential in JC-1 staining. Further, the transcriptional and translational studies confirmed the activation of TNF-α signaling pathway in TCS-treated cells thus enhancing the expression of RIPK1, RIPK3 and MLKL proteins and their phosphorylated forms. TCS was also found to increase the tau protein pathogenesis in Neuro-2a cells, which alludes to the development of tau-associated neurodegeneration. Altogether, this study confirms the neuroinflammatory actions of TCS in Neuro-2a cells involving a TNF-α-induced MLKL-mediated signaling.
三氯生（TCS）作为一种广谱抗菌剂，在化妆品和医疗保健行业中被广泛使用。TCS的亲脂性和持久性导致了严重的健康问题。在本研究中，我们评估了TCS对小鼠Neuro-2a细胞的神经炎症作用。初步研究证实，在TCS存在的情况下，细胞活力和形态呈剂量依赖性损失。转录和翻译研究证实，Neuro-2a细胞中自噬标志物的表达下调。共聚焦显微镜研究表明，TCS处理的细胞中自噬被废除是由于自噬通量的丧失和自噬体双层脂质化的阻止。荧光显微镜也证实，随着TCS浓度的增加，神经元细胞中自噬溶酶体的形成减少。TCS处理导致细胞中线粒体完整性丧失，这在JC-1染色中线粒体膜电位降低得到证实。此外，转录和翻译研究证实了TCS处理的细胞中TNF-α信号通路的激活，从而增强了RIPK1、RIPK3和MLKL蛋白及其磷酸化形式的表达。还发现TCS会增加Neuro-2a细胞中tau蛋白的发病机制，这暗示了tau相关神经退行性变的发展。总之，本研究证实了TCS在Neuro-2a细胞中的神经炎症作用，涉及TNF-α诱导的MLKL介导的信号传导。
