Abstract:
Standardization and validation of in vitro drug metabolism is essential for pre-clinical drug development as well as for in vitro toxicity assays including the lymphocyte toxicity assay (LTA) and the in vitro platelet toxicity assay (iPTA). Use of isolated liver microsomes (MIC) in in vitro testing has been utilized for a long time; however, the effect of species of origin and induction agents on the metabolic capacities of MIC is not adequately evaluated. In this study we investigated the impact of species of origin and induction agent on the capacity of MICs to bioactivate carbamazepine (CBZ) using cytotoxicity as a gross endpoint to measure the levels of cytotoxic metabolites generated by each type of MICs. Jurkat E6.1 cell line was used and MICs from human, rat, mouse, minipig and rabbit origin as well as rat MICs that is either non-induced or induced by phenobarbitone (PHB), dexamethasone (DEXA), 3-methylcholanthrene (3MC), clofibrate (CLOF) and isoniazid (INH) were investigated. MICs from minipig and rat MICs induced with 3MC exhibited the highest capacity to produce cytotoxic metabolites of CBZ. These findings will help optimize and standardize in vitro toxicity assays and provide guidance to pre-clinical investigation of drugs.
摘要:
体外药物代谢的标准化和验证对于临床前药物开发以及包括淋巴细胞毒性测定(LTA)和体外血小板毒性测定(iPTA)的体外毒性测定至关重要。在体外测试中使用分离的肝微粒体(MIC)已经使用了很长时间;但是,来源物种和诱导剂对MIC代谢能力的影响没有得到充分评估。在这项研究中,我们研究了来源和诱导剂对MIC生物激活卡马西平(CBZ)的能力的影响,使用细胞毒性作为总终点来测量每种类型的MIC产生的细胞毒性代谢物的水平。使用JurkatE6.1细胞系,来自人的MIC,rat,鼠标,小型猪和兔子的来源以及非苯巴比妥(PHB)诱导或诱导的大鼠MIC,地塞米松(DEXA),3-甲基胆蒽(3MC),研究了氯贝特(CLOF)和异烟肼(INH)。用3MC诱导的小型猪和大鼠MIC的MIC表现出最高的产生CBZ细胞毒性代谢产物的能力。这些发现将有助于优化和标准化体外毒性测定,并为药物的临床前研究提供指导。