Prins John M, Chao Chih-Kai, Jacobson Saskia M, Thompson Charles M, George Kathleen M
Department of Biomedical and Pharmaceutical Sciences, College of Health Professions and Biomedical Sciences, The University of Montana, Missoula, MT 59812, United States.
Department of Biomedical and Pharmaceutical Sciences, College of Health Professions and Biomedical Sciences, The University of Montana, Missoula, MT 59812, United States.
Toxicol In Vitro. 2014 Aug;28(5):715-21. doi: 10.1016/j.tiv.2014.01.009. Epub 2014 Jan 29.
Organophosphate (OP) compounds are used as insecticides, acaricides, and chemical agents and share a common neurotoxic mechanism of action. The biochemical alterations leading to many of the deleterious effects have been studied in neuronal cell lines, however, non-neuronal toxic effects of OPs are far less well characterized in vitro, and specifically in cell lines representing oral routes of exposure. To address this void, the human salivary gland (HSG) cell line, representing likely interactions in the oral cavity, was exposed to the representative OP paraoxon (PX; O,O-diethyl-p-nitrophenoxy phosphate) over a range of concentrations (0.01-100 μM) and analyzed for cytotoxicity. PX induced cytotoxicity in HSG cells at most of the exposure concentrations as revealed by MTT assay, however, the release of LDH only occurred at the highest concentration of PX tested (100 μM) at 48 h. Slight increases in cellular ATP levels were measured in PX-exposed (10 μM) HSG cells at 24 h. Exposing HSG cells to 10 μM PX also led to an increase in DNA fragmentation prior to loss of cellular membrane integrity implicating reactive oxygen species (ROS) as a trigger of toxicity. The ROS genes gss, gstm2, gstt2 and sod2 were upregulated, and the presence of superoxide following 10 μM PX exposure was determined via dihydroethidium fluorescence studies further implicating PX-induced oxidative stress in HSG cells.
有机磷酸酯（OP）化合物用作杀虫剂、杀螨剂和化学制剂，具有共同的神经毒性作用机制。导致许多有害影响的生化改变已在神经元细胞系中进行了研究，然而，OP的非神经毒性作用在体外，特别是在代表经口暴露途径的细胞系中，其特征远未明确。为填补这一空白，将代表口腔中可能相互作用的人唾液腺（HSG）细胞系暴露于一系列浓度（0.01 - 100 μM）的代表性OP对氧磷（PX；O，O - 二乙基 - 对硝基苯氧基磷酸酯）中，并分析其细胞毒性。MTT试验显示，在大多数暴露浓度下，PX均可诱导HSG细胞产生细胞毒性，然而，仅在48小时时，在所测试最高浓度的PX（100 μM）下观察到乳酸脱氢酶（LDH）释放。在24小时时，检测到暴露于10 μM PX的HSG细胞中细胞ATP水平略有增加。将HSG细胞暴露于10 μM PX还导致在细胞膜完整性丧失之前DNA片段化增加，这表明活性氧（ROS）是毒性的触发因素。ROS相关基因gss、gstm2、gstt2和sod2上调，通过二氢乙锭荧光研究确定了10 μM PX暴露后超氧化物的存在，进一步表明PX在HSG细胞中诱导了氧化应激。
