Identification of CYP5122A1 inhibitors as chemical probes for Leishmania biology

总结 人类利什曼病是一种毁灭性的传染病， 利什曼原虫属。这种疾病在90多个国家被发现，估计有1-2 全球每年有100万新感染者。利什曼病在返回的美国军事人员中也很常见 自2001年以来，报告的病例超过2000例。利什曼原虫 导致毁容皮肤溃疡（皮肤利什曼病或CL）和危及生命的重要内部感染 内脏利什曼病（内脏利什曼病或VL）VL（约占所有利什曼病病例的20%）是最危险和致命的 这种疾病的形式，如果不治疗，死亡率接近100%。它是第二致命的寄生虫 世界上最大的疾病（仅次于疟疾）。尽管在许多流行地区这是一个严重的公共卫生问题， 没有疫苗或预防性化疗可用于控制利什曼病。电流 抗利什曼病药物疗效有限，副作用严重，价格昂贵。因此，有一个重大的未解决问题， 医疗上需要安全有效的抗利什曼病药物。利什曼原虫CYP 5122 A1是一种新的 细胞色素P450（CYP 450）酶是L. Donovani是一种主要的致病因子， VL.独立和我们自己的研究使我们假设，选择性CYP 5122 A1的鉴定 作为化学探针的抑制剂将允许阐明其在麦角固醇生物合成中的重要作用， 利什曼原虫为了验证我们的假设，提出了三个具体的目标来回答三个主要问题：1）如何 CYP 5122 A1和CYP 51在麦角固醇生物合成途径中的生物化学作用是否比较 利什曼原虫？2)选择性CYP 5122 A1抑制剂是否可以鉴定和验证？和3）是芳基酰亚胺酰胺 （AIA）和/或AIA-唑杂合体的潜在化学探针，以帮助描述CYP 5122 A1的生化作用 在利什曼原虫生物学上拟议项目将采用创新的实验方法，例如，一 新的基于HPLC-MS/MS的甾醇测定、基于荧光的CYP 5122 A1和CYP 51抑制测定，以及 尖端的高内涵成像为基础的细胞内抗利什曼原虫检测。如果成功，我们的建议 一个鉴定新型CYP 5122 A1抑制剂的项目将阐明这种蛋白质在利什曼原虫生物学中的作用， 确认CYP 5122 A1作为药物靶点。这样的结果可能会对长期产生重大的积极影响。 利什曼病控制在地球仪上。

Summary Human leishmaniasis is a devastating infectious disease caused by protozoan parasites belonging to the genus of Leishmania. The disease is found in more than 90 countries and responsible for an estimated 1-2 million new infections each year worldwide. Leishmaniasis is also common in returning U.S. military personnel from Iraq and Afghanistan, with more than two thousand cases reported since 2001. Leishmania parasites cause disfiguring skin sores (cutaneous leishmaniasis or CL) and life-threatening infection of vital internal organs (visceral leishmaniasis or VL). VL (~20% of all leishmaniasis cases) is the most dangerous and fatal form of the disease, with a mortality rate close to 100% if left untreated. It is the second most deadly parasitic disease in the world (after malaria). Despite being a serious public health problem in many endemic regions, there are no vaccines or preventative chemotherapies available for leishmaniasis control. Current antileishmanial drugs have limited efficacy, serious side effects and high cost. Hence, there is a major unmet medical need for safe and effective drugs against leishmaniasis. Leishmanial CYP5122A1 is a novel cytochrome P450 (CYP) enzyme that is essential for the survival of L. donovani, a major causative agent for VL. Independent and our own studies have led us to hypothesize that identification of selective CYP5122A1 inhibitors as chemical probes will allow elucidation of its important role in the ergosterol biosynthesis by Leishmania. To test our hypothesis, three specific aims are proposed to answer three main questions: 1) How do the biochemical roles of CYP5122A1 and CYP51 compare in the ergosterol biosynthesis pathway of Leishmania? 2) Can selective CYP5122A1 inhibitors be identified and validated? and 3) Are arylimidamides (AIAs) and/or AIA-azole hybrids potential chemical probes to help delineate biochemical roles of CYP5122A1 in Leishmania biology? Innovative experimental approaches will be employed in the proposed project, e.g., a new HPLC-MS/MS-based sterol assay, fluorescence-based CYP5122A1 and CYP51 inhibition assays, and cutting-edge high content imaging-based intracellular antileishmanial assays. If successful, our proposed project to identify novel CYP5122A1 inhibitors will elucidate this protein’s role in Leishmania biology and validate CYP5122A1 as a drug target. Such an outcome could have a major positive impact on long-term leishmaniasis control around the globe.