Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, 40126 Bologna, Italy.
LTTA Center and University Center of Gender Medicine, Department of Translational Medicine, Section of Legal Medicine, University of Ferrara, 44121 Ferrara, Italy.
Int J Mol Sci. 2022 May 23;23(10):5849. doi: 10.3390/ijms23105849.
The novel psychoactive substance (NPS) 4-Methyl-5-(4-methylphenyl)-4,5-dihydroxazol-2-amine (4,4'-DMAR) shows psychostimulant activity. Data on the acute toxicity of 4,4'-DMAR are becoming increasingly available, yet the long-term effects are still almost unknown. In particular, no data on genotoxicity are available. Therefore, the aim of the present study was to evaluate its genotoxic potential using the "In Vitro Mammalian Cell Micronucleus Test" (MNvit) on (±)cis-4,4'-DMAR and (±)trans-4,4'-DMAR and their associations. The analyses were conducted in vitro on human TK6 cells. To select suitable concentrations for MNvit, we preliminarily evaluated cytotoxicity and apoptosis. All endpoints were analysed by flow cytometry. The results reveal the two racemates' opposite behaviours: (±)cis-4,4'-DMAR shows a statistically significant increase in micronuclei (MNi) frequency that (±)trans-4,4'-DMAR is completely incapable of. This contrast confirms the well-known possibility of observing opposite biological effects of the cis- and trans- isomers of a compound, and it highlights the importance of testing single NPSs that show even small differences in structure or conformation. The genotoxic capacity demonstrated stresses an additional alarming toxicological concern related to this NPS. Moreover, the co-treatments indicate that consuming both racemates will magnify the genotoxic effect, an aspect to consider given the unpredictability of illicit drug composition.
新型精神活性物质（NPS）4-甲基-5-(4-甲基苯基)-4,5-二氢恶唑-2-胺（4,4'-DMAR）具有精神兴奋活性。关于 4,4'-DMAR 的急性毒性数据越来越多，但长期影响仍几乎未知。特别是，没有关于遗传毒性的数据。因此，本研究旨在使用“体外哺乳动物细胞微核试验（MNvit）”评估其遗传毒性潜力(±)顺式-4,4'-DMAR 和 (±)反式-4,4'-DMAR 及其混合物。分析在人 TK6 细胞上进行。为了选择适合 MNvit 的浓度，我们初步评估了细胞毒性和细胞凋亡。所有终点均通过流式细胞术进行分析。结果揭示了两种外消旋体的相反行为：(±)顺式-4,4'-DMAR 显示微核（MNi）频率呈统计学显著增加，而 (±)反式-4,4'-DMAR 则完全不能。这种对比证实了化合物的顺式和反式异构体可能观察到相反的生物学效应的已知可能性，并强调了测试显示结构或构象稍有差异的单一 NPS 的重要性。所证明的遗传毒性能力强调了与这种 NPS 相关的另一个令人担忧的毒理学问题。此外，共同处理表明，同时摄入两种外消旋体将放大遗传毒性效应，鉴于非法药物成分的不可预测性，这是一个需要考虑的方面。
