Cong Yue, Guo Jinggong, Tang Zhi, Lin Shuhai, Zhang Qingchun, Li Jing, Cai Zongwei
Institute of Pharmacy, Pharmaceutical College, Henan University, Kaifeng, China Department of Chemistry, Hong Kong Baptist University, Kowloon, Hong Kong.
The Key Laboratory of Plant Stress Biology, Henan University, Kaifeng, China.
J Chromatogr Sci. 2015 Aug;53(7):1092-9. doi: 10.1093/chromsci/bmu171. Epub 2014 Dec 29.
Veratramine (VAM) is the major lipid-soluble alkaloid existing in Veratrum nigrum L. that has been demonstrated to exert neurotoxic effects. To better understand the potential mechanism of neurotoxicity of VAM, VAM-induced DNA damage was measured in the cerebellum and cerebral cortex of mice after a 7-day repetitive oral dose by using single-cell gel electrophoresis (comet assay). A method based on high-performance liquid chromatography-electrospray ionization tandem mass spectrometry was developed for the determination of VAM and its in vivo and in vitro metabolites, to establish the potential correlation between metabolites and neurotoxicity. In vitro experiment was carried out using rat liver microsomes, whereas the in vivo study was conducted on rats at a single dose of 3 mg/kg. The results showed that VAM caused DNA damage in the cerebellum and cerebral cortex of mice in a dose-dependent manner. Phenyl mono-oxidation, sulfate conjugation and phenyl di-oxidation were proposed to be the main in vivo metabolic pathways of VAM, whereas the major in vitro metabolic pathways were phenyl mono-oxidation, hydroxylation and methylation. Phenyl-oxidation reaction was likely to be associated with reactive oxygen species production, leading to the DNA damage in the mouse brain.
藜芦胺（VAM）是存在于黑藜芦中的主要脂溶性生物碱，已被证明具有神经毒性作用。为了更好地理解VAM神经毒性的潜在机制，通过单细胞凝胶电泳（彗星试验）测定了连续7天重复口服给药后小鼠小脑和大脑皮质中VAM诱导的DNA损伤。建立了一种基于高效液相色谱 - 电喷雾电离串联质谱法测定VAM及其体内外代谢产物的方法，以确定代谢产物与神经毒性之间的潜在相关性。体外实验使用大鼠肝微粒体进行，而体内研究则以3mg/kg的单剂量对大鼠进行。结果表明，VAM以剂量依赖性方式导致小鼠小脑和大脑皮质中的DNA损伤。推测苯单氧化作用、硫酸盐结合作用和苯双氧化作用是VAM主要的体内代谢途径，而体外主要代谢途径为苯单氧化作用、羟基化作用和甲基化作用。苯氧化反应可能与活性氧的产生有关，从而导致小鼠脑内的DNA损伤。
