Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY10461,United States.
Neurotoxicology. 2019 Sep;74:221-229. doi: 10.1016/j.neuro.2019.07.008. Epub 2019 Aug 2.
Triclosan (TCS) has been widely used as a disinfectant and antiseptic in multiple consumer and healthcare products due to its clinical effectiveness against various bacteria, fungi and protozoa. Recently, several studies have reported the adverse effects of TCS on various nerve cells, arousing concerns about its potential neurotoxicity. The present study aimed to investigate the neurotoxicity of TCS in rat pheochromocytoma PC12 cells. After differentiation, the stabilized PC12 cells were treated with 1, 10, 50 μM TCS for 12 h. At the end of the treatment, the generation of reactive oxygen species (ROS), protein expression of apoptotic-related genes, AMPK-AKT/mTOR, as well as p38 in PC12 cells were determined. The concentrations were chosen based on the results of cell viability and lactic dehydrogenase (LDH) assays in response to TCS treatment (ranging from 0.001 to 100 μM) for varied time periods. The results showed that TCS is cytotoxic to PC12 cells, causing decreased cell viability accompanied by increased LDH release. TCS treatment at 10 and 50 μM for 12 h increased the mRNA and protein expression of the pro-apoptotic gene Bax, while Bcl-2 levels remained unchanged. Moreover, an increase in the generation of reactive oxygen species (ROS) was found in TCS-treated PC12 cells at the concentrations of 1 and 10 μM. Pretreatment with 100 μM N-acetyl cysteine (NAC- ROS scavenger) for 1 h normalized the ROS generations in TCS-treated PC12 cells. Additionally, the suppression of the phosphorylation of Akt and mTOR was observed in TCS-treated PC12 cells at 10 and 50 μM for 12 h, concomitant with the activation of p38 MAPK pathway at 50 μM TCS. However, there were no effects of TCS on the phosphorylation of AMPK in these cells. Taken together, these results suggest that TCS may cause adverse effects and oxidative stress in PC12 cells accompanied by inhibition of Akt/mTOR and activation of p38.
三氯生（TCS）由于其对各种细菌、真菌和原生动物的临床有效性，已被广泛用作多种消费和医疗保健产品的消毒剂和防腐剂。最近，几项研究报告了 TCS 对各种神经细胞的不良影响，引起了人们对其潜在神经毒性的关注。本研究旨在探讨 TCS 对大鼠嗜铬细胞瘤 PC12 细胞的神经毒性。分化后，用 1、10、50μM TCS 处理稳定的 PC12 细胞 12 小时。在治疗结束时，测定 PC12 细胞中活性氧（ROS）的产生、凋亡相关基因的蛋白表达、AMPK-AKT/mTOR 以及 p38 的表达。这些浓度是根据细胞活力和乳酸脱氢酶（LDH）测定的结果选择的，这些结果是在不同时间段内（0.001 至 100μM）对 TCS 处理的反应得出的。结果表明，TCS 对 PC12 细胞具有细胞毒性，导致细胞活力下降，同时 LDH 释放增加。TCS 处理 10 和 50μM 12 小时后，促凋亡基因 Bax 的 mRNA 和蛋白表达增加，而 Bcl-2 水平保持不变。此外，在浓度为 1 和 10μM 的 TCS 处理的 PC12 细胞中发现活性氧（ROS）的产生增加。用 100μM N-乙酰半胱氨酸（NAC-ROS 清除剂）预处理 1 小时可使 TCS 处理的 PC12 细胞中的 ROS 产生正常化。此外，在浓度为 10 和 50μM 的 TCS 处理的 PC12 细胞中观察到 Akt 和 mTOR 的磷酸化受到抑制 12 小时，同时在 50μM TCS 下激活 p38 MAPK 途径。然而，TCS 对这些细胞中 AMPK 的磷酸化没有影响。综上所述，这些结果表明，TCS 可能导致 PC12 细胞产生不良影响和氧化应激，同时抑制 Akt/mTOR 并激活 p38。
