Vichi S, Sandström von Tobel J, Gemma S, Stanzel S, Kopp-Schneider A, Monnet-Tschudi F, Testai E, Zurich M G
Istituto Superiore di Sanità, Environment and Primary Prevention Department, Mechanisms of Toxicity Unit, Rome, Italy.
Department of Physiology, University of Lausanne, Lausanne, Switzerland; Swiss Center for Applied Human Toxicology (SCAHT), Switzerland.
Toxicol In Vitro. 2015 Dec 25;30(1 Pt A):176-84. doi: 10.1016/j.tiv.2015.03.005. Epub 2015 Mar 17.
Within the Predict-IV FP7 project a strategy for measurement of in vitro biokinetics was developed, requiring the characterization of the cellular model used, especially regarding biotransformation, which frequently depends on cytochrome P450 (CYP) activity. The extrahepatic in situ CYP-mediated metabolism is especially relevant in target organ toxicity. In this study, the constitutive mRNA levels and protein localization of different CYP isoforms were investigated in 3D aggregating brain cell cultures. CYP1A1, CYP2B1/B2, CYP2D2/4, CYP2E1 and CYP3A were expressed; CYP1A1 and 2B1 represented almost 80% of the total mRNA content. Double-immunolabeling revealed their presence in astrocytes, in neurons, and to a minor extent in oligodendrocytes, confirming the cell-specific localization of CYPs in the brain. These results together with the recently reported formation of an amiodarone metabolite following repeated exposure suggest that this cell culture system possesses some metabolic potential, most likely contributing to its high performance in neurotoxicological studies and support the use of this model in studying brain neurotoxicity involving mechanisms of toxication/detoxication.
在“Predict-IV FP7项目”中，开发了一种体外生物动力学测量策略，这需要对所使用的细胞模型进行表征，特别是在生物转化方面，而生物转化通常依赖于细胞色素P450（CYP）活性。肝外原位CYP介导的代谢在靶器官毒性中尤为重要。在本研究中，研究了3D聚集脑细胞培养物中不同CYP亚型的组成型mRNA水平和蛋白质定位。CYP1A1、CYP2B1/B2、CYP2D2/4、CYP2E1和CYP3A均有表达；CYP1A1和2B1占总mRNA含量的近80%。双重免疫标记显示它们存在于星形胶质细胞、神经元中，在少突胶质细胞中含量较少，证实了CYPs在脑中的细胞特异性定位。这些结果与最近报道的重复暴露后形成胺碘酮代谢物的结果一起表明，这种细胞培养系统具有一定的代谢潜力，很可能有助于其在神经毒理学研究中的高性能，并支持使用该模型研究涉及中毒/解毒机制的脑神经毒性。
