Department of Pharmacology, Hanyang University, Sungdong-Gu, Heandang-Dong 17, Seoul, Republic of Korea.
Neurochem Int. 2012 Jun;60(8):773-81. doi: 10.1016/j.neuint.2012.03.007. Epub 2012 Mar 21.
Although the underlying cause of Parkinson's disease (PD) is not well characterized, epidemiological studies suggest that exposure to agricultural chemicals is a risk factor for PD. Fluazinam (FZN) is a new active ingredient for the control of grey mould, belonging to the novel broad spectrum phenylpyridinamine fungicides. We used human neuroblastoma SH-SY5Y cells to investigate mechanisms of dopaminergic cell death in response to FZN. FZN treatment produced dose-dependent cytotoxicity, and decreased the tyrosine hydroxylase (TH) expression in SH-SY5Y cells. We provided evidence for the occurrence of oxidative stress and oxidative damage during FZN exposure on dopaminergic cells through the measurement of reactive oxygen species (ROS) in cells with DCFH-DA. The cytotoxic effects of FZN appear to involve an increase in ROS generation since pretreatment with N-acetyl cysteine (NAC), an anti-oxidant, reduced cell death. After FZN treatment, dopamine (DA) levels decreased in both cell and culture media, and oxidative effects of FZN were blocked by NAC pretreatment. We show that cell death in response to FZN was due to apoptosis since FZN exposure results in an increased in cytochrome c release into the cytosol and activated caspase-3 through p38 and JNK signaling. Furthermore, the blocking of p38 or JNK signaling inhibits FZN-induced cell death. Phosphorylation of mitogen-activated protein kinases precedes cytochrome c release and caspase-3 activation. This cellular response is characteristic of mitochondrial dysfunction. Therefore, we also investigated the effect of FZN on mitochondrial complex I activity in FZN-treated cell. Interestingly, we show that FZN inhibited the complex I activity. Thus in this study, we report a new mode of action by which the fungicide FZN could triggers apoptosis.
虽然帕金森病（PD）的根本原因尚未得到很好的描述，但流行病学研究表明，接触农业化学品是 PD 的一个风险因素。氟唑菌酰胺（FZN）是一种新型广谱苯并吡嗪类杀菌剂，用于防治灰霉病。我们使用人神经母细胞瘤 SH-SY5Y 细胞来研究 FZN 诱导多巴胺能细胞死亡的机制。FZN 处理产生剂量依赖性细胞毒性，并降低 SH-SY5Y 细胞中的酪氨酸羟化酶（TH）表达。我们通过用 DCFH-DA 测量细胞内的活性氧物种（ROS），为 FZN 暴露期间多巴胺能细胞发生氧化应激和氧化损伤提供了证据。FZN 的细胞毒性作用似乎涉及 ROS 生成的增加，因为抗氧化剂 N-乙酰半胱氨酸（NAC）预处理可降低细胞死亡。FZN 处理后，细胞和培养基中的多巴胺（DA）水平均降低，NAC 预处理可阻断 FZN 的氧化作用。我们表明，FZN 诱导的细胞死亡是由于细胞凋亡所致，因为 FZN 暴露导致细胞色素 c 释放到细胞质中，并通过 p38 和 JNK 信号激活 caspase-3。此外，阻断 p38 或 JNK 信号可抑制 FZN 诱导的细胞死亡。丝裂原激活的蛋白激酶的磷酸化先于细胞色素 c 释放和 caspase-3 激活。这种细胞反应是线粒体功能障碍的特征。因此，我们还研究了 FZN 对 FZN 处理细胞中线粒体复合物 I 活性的影响。有趣的是，我们表明 FZN 抑制了复合物 I 的活性。因此，在这项研究中，我们报告了一种新的作用模式，即杀菌剂 FZN 可能引发细胞凋亡。
