Laboratory of Immunomodulation and Protozoology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, RJ, Brazil.
Laboratory of Medicinal and Computational Chemistry, Institute of Physics of São Carlos, University of São Paulo, São Carlos, SP, Brazil.
Front Cell Infect Microbiol. 2022 Aug 25;12:974910. doi: 10.3389/fcimb.2022.974910. eCollection 2022.
Leishmaniasis represents a serious world health problem, with 1 billion people being exposed to infection and a broad spectrum of clinical manifestations with a potentially fatal outcome. Based on the limitations observed in the treatment of leishmaniasis, such as high cost, significant adverse effects, and the potential for drug resistance, the aim of the present study was to evaluate the leishmanicidal activity of the compounds pseurotin A and monomethylsulochrin isolated from the biomass extract of sp. The chromatographic profiles of the extract were determined by high-performance liquid chromatography coupled with a diode-array UV-Vis detector (HPLC-DAD-UV), and the molecular identification of the pseurotin A and monomethylsulochrin were carried out by electrospray ionization mass spectrometry in tandem (LC-ESI-MS-MS) and nuclear magnetic resonance (NMR). Antileishmanial activity was assayed against promastigote and intracellular amastigote of . As a control, cytotoxicity assays were performed in non-infected BALB/c peritoneal macrophages. Ultrastructural alterations in parasites were evaluated by transmission electron microscopy. Changes in mitochondrial membrane potential were determined by flow cytometry. Only monomethylsulochrin inhibited the promastigote growth (IC 18.04 ± 1.11 µM), with cytotoxicity to peritoneal macrophages (CC 5.09 91.63 ± 1.28 µM). Activity against intracellular amastigote forms (IC 5.09 ± 1.06 µM) revealed an increase in antileishmanial activity when compared with promastigotes. In addition to a statistically significant reduction in the evaluated infection parameters, monomethylsulochrin altered the ultrastructure of the promastigote forms with atypical vacuoles, electron-dense corpuscles in the cytoplasm, changes at the mitochondria outer membrane and abnormal disposition around the kinetoplast. It was showed that monomethylsulochrin leads to a decrease in the mitochondrial membrane potential (25.9%, = 0.0286). Molecular modeling studies revealed that monomethylsulochrin can act as inhibitor of sterol 14-alpha-demethylase (CYP51), a therapeutic target for human trypanosomiasis and leishmaniasis. Assessed for its drug likeness, monomethylsulochrin follows the Lipinski Rule of five and Ghose, Veber, Egan, and Muegge criteria. Furthermore, monomethylsulochrin can be used as a reference in the development of novel and therapeutically useful antileishmanial agents.
利什曼病是一个严重的世界性健康问题，全球有 10 亿人面临感染风险，且临床表现广泛，具有潜在致命性。鉴于利什曼病治疗存在诸多局限性，如费用高、不良反应大以及存在耐药性等，本研究旨在评估从 sp. 生物质提取物中分离得到的 pseurotin A 和 monomethylsulochrin 的杀利什曼原虫活性。采用高效液相色谱-二极管阵列紫外可见检测器（HPLC-DAD-UV）测定提取物的色谱图，并通过电喷雾串联质谱（LC-ESI-MS-MS）和核磁共振（NMR）对 pseurotin A 和 monomethylsulochrin 进行分子鉴定。采用体外试验测定化合物对前鞭毛体和细胞内无鞭毛体的抗利什曼原虫活性。以非感染的 BALB/c 腹腔巨噬细胞为对照进行细胞毒性测定。采用透射电子显微镜观察寄生虫的超微结构变化。采用流式细胞术测定线粒体膜电位变化。结果显示，只有 monomethylsulochrin 抑制前鞭毛体生长（IC 18.04 ± 1.11 μM），对腹腔巨噬细胞具有细胞毒性（CC 5.09 91.63 ± 1.28 μM）。与前鞭毛体相比，monomethylsulochrin 对细胞内无鞭毛体形式的活性（IC 5.09 ± 1.06 μM）增加，显示出更强的抗利什曼原虫活性。除了评估感染参数有统计学意义的降低外，monomethylsulochrin 还改变了前鞭毛体的超微结构，形成非典型空泡，细胞质中电子致密颗粒，线粒体外膜改变以及动基体周围的异常排列。结果表明，monomethylsulochrin 导致线粒体膜电位降低（25.9%， = 0.0286）。分子模拟研究表明，monomethylsulochrin 可以作为固醇 14-α-去甲基酶（CYP51）的抑制剂，CYP51 是人类锥虫病和利什曼病的治疗靶点。根据类药性评估，monomethylsulochrin 符合 Lipinski 五规则和 Ghose、Veber、Egan 和 Muegge 标准。此外，monomethylsulochrin 可以作为开发新型和治疗性有用抗利什曼原虫药物的参考。
