Laboratory of Immunopathology, Institute of Biomedical Sciences, Federal University of Uberlândia, Av. Pará 1720, Uberlândia, CEP 38400902, MG, Brazil.
Laboratory of Biochemistry and Molecular Biology, Institute of Biotechnology - Federal University of Uberlândia, Av. Pará, 1720, 38400-902, Uberlândia, MG Brazil.
J Ethnopharmacol. 2021 Jun 12;273:114019. doi: 10.1016/j.jep.2021.114019. Epub 2021 Mar 12.
Sulfadiazine and pyrimethamine are the two drugs used as part of the standard therapy for toxoplasmosis, however; they may cause adverse side effects and fail to prevent relapse in many patients, rendering infected individuals at risk of reactivation upon becoming immunocompromised. Extracts from various parts of Annona muricata have been widely used medicinally for the management, control and/or treatment of several human diseases, acting against parasites that cause diseases in humans.
This study was performed to investigate the action of the ethanolic extract of A. muricata (EtOHAm) and its fractions in the control of the apicomplexan parasite Toxoplasma gondii in vitro and in vivo, and the effect of EtOHAm on the inflammatory response and lipid profile alteration induced by in vivo T. gondii infection.
The cytotoxicity of EtOHAm and its fractions ethyl acetate (EtOAcAm), n-butanol (BuOHAm), aqueous (HOAm), hexane (HexAm) and dichloromethane (CHClAm) was evaluated in NIH/3T3 fibroblasts using the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The cells were infected with T. gondii, treated with the extracts, and parasite proliferation was analyzed. For the in vivo experiments, C57BL/6 mice were orally infected with T. gondii and, treated with different concentrations of extract fractions that were effective in vitro (EtOHAm, EtOAcAm, HexAm and CHClAm). Tissue parasitism, histological alterations, systemic cytokine and lipid profile were investigated.
EtOHAm, EtOAcAm, BuOHAm, HOAm presented low cytotoxicity until doses of 200 μg/mL, while HexAm and CHClAm presented toxicity from doses of 100μg/mL. EtOHAm, HexAm and CHClAm decreased the parasitism in vitro, presenting a therapeutic index of 2.62, 2.44, and 2.96, respectively. In vivo, EtOHAm, HexAm and CHClAm improved the survival rate of infected animals, however, only EtOHAm was able to decrease the parasitism in the small intestine and lung. Additionally, EtOHAm decreased the systemic interferon (IFN)-γ and tumor necrosis factor (TNF) systemically in infected mice, and was able to maintain the triglycerides and very-low-density lipoprotein (VLDL) lipid fractions at similar levels to uninfected animals. Although treatment with EtOHAm could not control the inflammation induced by oral infection in the tissues analyzed, it was able to preserve the number of goblet cells in the small intestine.
Ethanolic A. muricata leaf extract could be considered as a good candidate for the development of a complementary/alternative therapy against toxoplasmosis, and also as an anti-inflammatory alternative for decreasing TNF and IFN-γ concentrations and lipid fractions in specific diseases.
磺胺嘧啶和乙胺嘧啶是用于弓形虫病标准治疗的两种药物，然而，它们可能会引起不良反应，并且无法预防许多患者的复发，使感染个体在免疫功能低下时面临复发的风险。安农纳木瓜的各个部分的提取物已被广泛用于医学上，用于管理、控制和/或治疗多种人类疾病，对抗引起人类疾病的寄生虫。
本研究旨在研究安农纳木瓜（EtOHAm）及其各部分的乙醇提取物在体外和体内控制刚地弓形虫的作用，以及 EtOHAm 对体内感染弓形虫引起的炎症反应和脂质谱改变的影响。
使用（3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四唑溴化物（MTT）测定法在 NIH/3T3 成纤维细胞中评估 EtOHAm 及其乙酯（EtOAcAm）、正丁醇（BuOHAm）、水（HOAm）、己烷（HexAm）和二氯甲烷（CHClAm）的细胞毒性。用提取物处理感染弓形虫的细胞，分析寄生虫增殖情况。对于体内实验，用 T. gondii 口服感染 C57BL/6 小鼠，并以体外有效浓度的不同提取物（EtOHAm、EtOAcAm、HexAm 和 CHClAm）处理。研究组织寄生虫病、组织学改变、全身细胞因子和脂质谱。
EtOHAm、EtOAcAm、BuOHAm、HOAm 直至 200μg/mL 剂量时表现出低细胞毒性，而 HexAm 和 CHClAm 从 100μg/mL 剂量开始具有毒性。EtOHAm、HexAm 和 CHClAm 在体外减少寄生虫感染，分别具有 2.62、2.44 和 2.96 的治疗指数。在体内，EtOHAm、HexAm 和 CHClAm 提高了感染动物的存活率，但只有 EtOHAm 能够降低小肠和肺部的寄生虫感染。此外，EtOHAm 降低了感染小鼠的全身干扰素（IFN）-γ和肿瘤坏死因子（TNF）系统，并且能够将甘油三酯和极低密度脂蛋白（VLDL）脂质保持在与未感染动物相似的水平。尽管 EtOHAm 治疗不能控制组织中弓形虫感染引起的炎症，但它能够维持小肠中杯状细胞的数量。
安农纳木瓜叶乙醇提取物可被视为开发弓形虫病辅助/替代疗法的良好候选物，也可作为降低 TNF 和 IFN-γ 浓度和特定疾病脂质谱的抗炎替代物。
