PDF(Pubmed)
Abstract：
Toxoplasma gondii, an important opportunistic pathogen, underscores the necessity of developing novel therapeutic drugs and identifying new drug targets. Our findings indicate that the half-maximal inhibitory concentrations (IC50) of KU60019 and CP466722 (abbreviated as KU and CP) against T. gondii are 0.522 μM and 0.702 μM, respectively, with selection indices (SI) of 68 and 10. Treatment with KU and CP affects the in vitro growth of T. gondii, inducing aberrant division in the daughter parasites. Transmission electron microscopy reveals that KU and CP prompt the anomalous division of T. gondii, accompanied by cellular enlargement, nuclear shrinkage, and an increased dense granule density, suggesting potential damage to parasite vesicle transport. Subsequent investigations unveil their ability to modulate the expression of certain secreted proteins and FAS II (type II fatty acid synthesis) in T. gondii, as well as including the dot-like aggregation of the autophagy-related protein ATG8 (autophagy-related protein 8), thereby expediting programmed death. Leveraging DARTS (drug affinity responsive target stability) in conjunction with 4D-Label-free quantitative proteomics technology, we identified seven target proteins binding to KU, implicated in pivotal biological processes such as the fatty acid metabolism, mitochondrial ATP transmission, microtubule formation, and Golgi proteins transport in T. gondii. Molecular docking predicts their good binding affinity. Furthermore, KU has a slight protective effect on mice infected with T. gondii. Elucidating the function of those target proteins and their mechanism of action with ATM kinase inhibitors may potentially enhance the treatment paradigm for toxoplasmosis.
摘要：
弓形虫,一种重要的机会病原体，强调开发新的治疗药物和确定新的药物靶点的必要性。我们的发现表明，KU60019和CP466722（缩写为KU和CP）对弓形虫的半最大抑制浓度（IC50）为0.522μM和0.702μM，分别,选择指数(SI)为68和10。用KU和CP处理影响弓形虫的体外生长，在子寄生虫中诱导异常分裂。透射电子显微镜显示KU和CP提示弓形虫异常分裂，伴随着细胞增大，核收缩，和增加的致密颗粒密度，提示寄生虫囊泡运输的潜在损害。随后的研究揭示了它们调节弓形虫中某些分泌蛋白和FASII（II型脂肪酸合成）表达的能力，以及包括自噬相关蛋白ATG8（自噬相关蛋白8）的点状聚集，从而加速程序性死亡。利用DARTS（药物亲和力反应靶标稳定性）与4D-Label-free定量蛋白质组学技术，我们确定了七种与KU结合的靶蛋白，涉及关键的生物过程，如脂肪酸代谢，线粒体ATP传递，微管形成,弓形虫中的高尔基蛋白转运。分子对接预测它们良好的结合亲和力。此外，KU对感染弓形虫的小鼠有轻微的保护作用。阐明这些靶蛋白的功能及其与ATM激酶抑制剂的作用机制可能潜在地增强弓形虫病的治疗范例。
