Metabolism and detection of designer benzodiazepines: a systematic review

Synthesis and illicit use of designer benzodiazepines are growing concerns, with these new psychoactive substances (NPS) posing serious health consequences and new hurdles for toxicologists. Consumption marker identification and characterization is paramount in confirming their use. The benzodiazepine core structure is a fusion of benzene and a seven-membered heterocycle with two nitrogen atoms forming the diazepine ring. Minor variations on the core structure produce different classes of benzodiazepines with marked differences in physiological effects. The present review provides a comprehensive designer benzodiazepines metabolism overview and suggests suitable human consumption biomarkers for toxicology casework. A systematic literature search of PubMed^®, Scopus^TM, Web of Science^TM, and Cochrane databases was conducted independently by two coauthors adhering to PRISMA guidelines. Data from 30 <i>in vitro</i> and <i>in vivo</i> models of designer benzodiazepines metabolism from January 2007 to February 2023 were included. 1,4-benzodiazepines (<i>n</i> = 10), 2,3-benzodiazepines (<i>n</i> = 1), triazolo-benzodiazepines (<i>n</i> = 9), and thieno-triazolo-benzodiazepines (<i>n</i> = 3) study design, sample pretreatment, analytical techniques, and major metabolites detected in various matrices are addressed. Metabolites following hydroxylation and phase II glucuronide conjugation were the most prevalent analytes. <i>N</i>-Glucuronidation of parent azole-fused benzodiazepines, and nitro-reduced and <i>N</i>-acetylated metabolites of nitro-containing designer benzodiazepines were also common. From these data, we propose a generic metabolic pathway for designer benzodiazepines. The sporadic illicit market presents challenges in toxicological casework and necessitates comprehensive biomarker investigations, especially in cases with legal implications. There are few metabolism data for many designer benzodiazepines, emphasizing the need for research focusing on closing these gaps.

设计类苯二氮䓬类药物（designer benzodiazepines）的合成与非法使用问题日益突出，这类新精神活性物质（new psychoactive substances, NPS）会造成严重健康危害，同时也给毒理学家带来了新的挑战。确认此类物质的使用情况，首要任务是识别并表征其消费标志物。苯二氮䓬类的核心结构为苯环与含两个氮原子的七元杂环稠合形成的二氮䓬环。核心结构的细微差异可生成不同类别苯二氮䓬类药物，其生理效应存在显著差异。本综述全面概述了设计类苯二氮䓬类药物的代谢情况，并为毒理案例检验工作推荐了适用的人体消费生物标志物。两位作者按照系统综述与元分析首选报告条目（PRISMA）指南，独立对PubMed®、Scopus™、Web of Science™及Cochrane数据库进行了系统性文献检索。本研究纳入了2007年1月至2023年2月期间，关于设计类苯二氮䓬类药物代谢的30项体外（in vitro）及体内（in vivo）模型研究数据。本综述涵盖了1,4-苯二氮䓬类（n=10）、2,3-苯二氮䓬类（n=1）、三唑并苯二氮䓬类（n=9）以及噻吩并三唑并苯二氮䓬类（n=3）的研究设计、样本前处理方法、分析技术及各类生物基质中检出的主要代谢产物。经羟基化修饰及II相葡萄糖醛酸化结合反应生成的代谢产物为最主要的检出物。母核含唑环稠合的苯二氮䓬类药物的N-葡萄糖醛酸化反应，以及含硝基的设计类苯二氮䓬类药物的硝基还原代谢物和N-乙酰化代谢产物也较为常见。基于上述数据，本研究提出了设计类苯二氮䓬类药物的通用代谢通路。零星出现的非法市场给毒理检验工作带来了挑战，因此需要开展全面的生物标志物研究，尤其是涉及法律纠纷的案件中。目前多数设计类苯二氮䓬类药物的代谢数据仍较为匮乏，这凸显了填补相关研究空白的必要性。