CYP3A4/5 mediates the metabolic detoxification of humantenmine, a highly toxic alkaloid from Gelsemium elegans Benth.
CYP3A4/5 mediates the metabolic detoxification of humantenmine, a highly toxic alkaloid from Gelsemium elegans Benth.
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DOI：
10.1002/jat.3813
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发表时间：
2019-09-01
影响因子：
3.3
通讯作者：
Ye, Ling
中科院分区：
文献类型：
--
作者：
Sun, Rongjin;Chen, Minghao;Ye, Ling
钩吻是一种著名的有毒草本植物，广泛用于治疗风湿性关节炎、炎症等疾病。钩吻中含有人藤胺，是一种重要的生物活性和毒性生物碱。细胞色素P450酶在外源物质的清除和解毒中起着重要的作用。本研究旨在探讨细胞色素P450在HMT代谢和解毒中的作用。首先，利用人肝微粒体、选择性化学抑制剂和重组人细胞色素P450进行了体外代谢研究。结果表明，在人肝微粒体中发现了四种代谢物，包括羟化代谢物和氧化代谢物，并根据其高分辨质谱图进行了鉴定。参与HMT代谢的亚型主要为CYP3A4/5。其次，在NADPH存在的情况下，HMT对L02细胞的毒性明显低于不存在NADPH的细胞。采用小鼠腹腔注射酮康唑的方法建立细胞色素P3A4/5活性抑制模型，观察其在HMT解毒中的作用。在该模型中，灌胃HMT后，小鼠14d存活率降至17%，并伴有肝损伤和丙氨酸氨基转移酶(ALT)/天冬氨酸氨基转移酶(AST)水平的升高。总体而言，CYP3A4/5介导了HMT的代谢和解毒。
Gelsemium elegans Benth., a well-known toxic herbal plant, is widely used to treat rheumatic arthritis, inflammation and other diseases. Gelsemium contains humantenmine (HMT), which is an important bioactive and toxic alkaloid. Cytochrome P450 enzymes (CYPs) play important roles in the elimination and detoxification of exogenous substances. This study aimed to investigate the roles of CYPs in the metabolism and detoxification of HMT. First, metabolic studies were performed in vitro by using human liver microsomes, selective chemical inhibitors and recombinant human CYPs. Results indicated that four metabolites, including hydroxylation and oxidation metabolites, were found in human liver microsomes and identified based on their high-resolution mass spectrum. The isoform responsible for HMT metabolism was mainly CYP3A4/5. Second, the toxicity of HMT on L02 cells in the presence of the nicotinamide adenine dinucleotide phosphate system (NADPH) was significantly less than that without NADPH system. A CYP3A4/5 activity inhibition model was established by intraperitoneally injecting ketoconazole in mice and used to evaluate the role of CYP3A4/5 in HMT detoxification. In this model, the 14-day survival rate of the mice decreased to 17% after they were intragastrically treated with HMT, along with hepatic injury and increasing alanine aminotransferase (ALT) /aspartate aminotransferase (AST) levels. Overall, CYP3A4/5 mediated the metabolism and detoxification of HMT.