Artemisinin activation in artemisinin resistant malarial parasites

目前，青蒿素（ART）联合疗法（ACT）是唯一普遍有效的 治疗与全球所有疟疾相比。然而，令人不安的是，ART耐药性（ArtR）的先兆 出现在东南亚，被称为“延迟清除表型”（DCP）。阐明 DCP/ArtR的分子机制是当今感染性疾病研究中最紧迫的问题之一。 多种遗传决定因素已被描述为DCP，最常见的是突变在 PfK 13基因，但目前没有一个统一的分子机制DCP是已知的。本集团一直 第一个将靶向代谢组学应用于ART药物药理学和ArtR分析。本质上 我们的疟疾寄生虫培养、分离和提取方法，结合液相色谱法， 质谱（LCMS）技术，使我们能够量化，第一次，ART药物- FPIX 血红素共价加合物在活的疟疾寄生虫内形成。我们的假设是ART药物- FPIX 血红素加合物形成与ArtR相关，且加合物丰度预测ArtR的严重性（“折叠” ArtR）。我们将使用这些新完善的方法来测试有吸引力的假设，加合物丰度是 与ArtR进展的严重程度相关。我们的工作将是全面和跨度分析 形成的加合物与多种天然和合成ART药物和ACT组合，以及多种 携带所有常见PfK 13突变或似乎不携带PfK 13的ArtR寄生虫类型 突变的一切。

Currently artemisinin (ART) combination therapies (ACTs) are the only universally effective treatments vs all malaria worldwide. Troublingly however, a harbinger of ART drug resistance (ArtR) has emerged in South East Asia, referred to as the "delayed clearance phenotype" (DCP). Elucidation of the molecular mechanism of DCP/ArtR is one of the most pressing issues in infectious disease research today. Multiple genetic determinants have been described for DCP, with the most common being mutations in the PfK13 gene, but currently no single unifying molecular mechanism for DCP is known. Our group has been the first to apply targeted metabolomics to the analysis of ART drug pharmacology and ArtR. In essence our malarial parasite culture, fractionation, and extraction methods, combined with liquid chromatography - mass spectrometry (LCMS) techniques, have allowed us to quantify, for the first time, ART drug - FPIX heme covalent adducts formed within live malarial parasites. Our hypothesis is that ART drug - FPIX heme adduct formation correlates with ArtR, and that adduct abundance predicts the severity of ArtR ("fold" ArtR). We will use these newly perfected methods to test the attractive hypothesis that adduct abundance is correlated with the degree of severity of evolving ArtR. Our work will be comprehensive and span analysis of adducts formed vs multiple natural and synthetic ART drugs and ACT combinations, as well as multiple types of ArtR parasites that harbor all common PfK13 mutations or that do not appear to harbor PfK13 mutations at all.