Exploring metabolic resistance to small molecule inhibitors in Trypanosoma cruzi

项目摘要 慢性感染原虫寄生虫和人类恰加斯病的病原体锥虫 克鲁兹是出了名的具有挑战性的治疗。现有的药物往往不能达到灭菌治愈的目的 目前的治疗方案。麦角甾醇生物合成抑制剂(EBIs)也无法清除慢性寄生虫 最近的临床试验中的患者。这些发现，加上动物模型的结果显示，选择性 克氏毛滴虫在EBI治疗后在某些组织中的存活，增加了局部特点的可能性 组织环境影响细胞内寄生虫对杀锥虫药物的敏感性。在癌症领域，它是 众所周知，由于细胞群体的异质性，肿瘤细胞代谢状态的差异 以及它们所处的环境，可能会导致“代谢抵抗”和治疗失败。因为克氏锥虫侵占了 哺乳动物宿主中的不同组织，每个组织都有自己独特的代谢特征，我们假设 类似的代谢耐药机制可能导致抗锥虫药物治疗失败 实现克氏毛滴虫慢性感染的寄生虫治疗。初步研究表明，这与这一想法一致 细胞培养液成分的单一改变就能保护细胞内的克氏锥虫无鞭毛虫 不受EB病毒的致命影响。这项拟议研究的目标是确定谷氨酰胺的作用。 用分子遗传学和分子生物学相结合的方法研究克氏锥虫无鞭毛体对EBIS的敏化代谢 生化方法(Aim1)，并确定代谢环境对疗效的更广泛影响 通过重新筛选克氏锥虫ChagagBox集合来筛选下一代候选抗锥虫药物 不同条件下的生长抑制剂(目标2)。作为代谢抵抗的案例研究，建议的 这项研究解决了我们对不同的细胞和代谢环境如何理解的一个关键差距，如 由于克氏锥虫在体内遇到的那些，影响了有效地从感染中消除这种病原体的能力 宿主，这是目前治疗恰加斯病的一个关键挑战。

Project Summary Chronic infections with the protozoan parasite and causative agent of human Chagas disease, Trypanosoma cruzi, are notoriously challenging to treat. The available drugs often fail to achieve sterilizing cure under the current treatment regimens. Ergosterol biosynthesis inhibitors (EBIs) also failed to clear parasites from chronic patients in recent clinical trials. These findings, coupled with results from animal models showing selective survival of T. cruzi in certain tissues after EBI treatment, raise the possibility that characteristics of the local tissue environment impact susceptibility of intracellular parasites to trypanocidal drugs. In the cancer field, it is well-established that differences in the metabolic state of tumor cells, due to heterogeneity of cell populations and their environments, can lead to `metabolic resistance' and treatment failure. Because T. cruzi colonizes diverse tissues in the mammalian host, each with its own unique metabolic signature, we hypothesize that comparable mechanisms of metabolic resistance to anti-trypanosomal drugs may contribute to failure to achieve parasitological cure in chronic T. cruzi infection. Consistent with this idea, preliminary studies show that a single change in the composition of the cell culture medium protects intracellular T. cruzi amastigotes from the lethal effects of EBIs. The goals of this proposed study are to determine the role of glutamine metabolism in sensitizing T. cruzi amastigotes to EBIs using a combination of molecular genetic and biochemical approaches (Aim1) and to determine the broader impact of metabolic environment on the efficacy of the next generation of candidate anti-trypanosomals by re-screening the ChagasBox collection of T. cruzi growth inhibitors under diverse conditions (Aim 2). As a case study for metabolic resistance, the proposed study addresses a critical gap in our understanding of how diverse cellular and metabolic environments, such as those encountered by T. cruzi in vivo, impact the ability to effectively eliminate this pathogen from infected hosts, a key current challenge in the treatment of Chagas disease.