Medical Microbiology Laboratory, Universidade Federal de São João del-Rei (UFSJ), Divinópolis, Minas Gerais, Brazil; Molecular Biology Laboratory, Universidade Federal de São João Del Rei (UFSJ), Divinópolis, Minas Gerais, Brazil.
Faculty of Pharmacy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
J Ethnopharmacol. 2022 Dec 5;299:115685. doi: 10.1016/j.jep.2022.115685. Epub 2022 Sep 5.
Mayaro fever is a neglected tropical disease. The region of the most significant circulation of the Mayaro virus (MAYV) is the Amazon rainforest, situated in remote areas that are difficult to access and where medicine is scarce. Thus, the regional population uses plants as an alternative for the treatment of various diseases. Fridericia chica is an endemic plant of tropical regions used in traditional medicine to treat fever, malaise, inflammation, and infectious diseases such as hepatitis B. However, its antiviral activity is poorly understood.
This study aimed to investigate the anti-MAYV activity of the hydroethanolic extract of the leaves of Fridericia chica (HEFc) in mammalian cells and its possible mechanism of action.
The antiviral activity of HEFc was studied using Vero cell lines against MAYV. The cytotoxicity and antiviral activity of the extract were evaluated by the 3-(4, 5- dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. The overall antiviral activity was confirmed by the plaque forming units (PFU) method. Then, the effects of HEFc on MAYV multiplication kinetics, virus adsorption, penetration, and post-penetration, and its virucidal activity were determined in Vero cells using standard experimental procedures.
HEFc exerted a effect against viral infection in Vero cells at a non-cytotoxic concentration, and no virion was detected in the supernatant in a dose-dependent and selective manner. HEFc inhibited MAYV in the early and late stages of the viral multiplication cycle. The extract showed significant virucidal activity at low concentrations and did not affect adsorption or viral internalization stages. In addition, HEFc reduced virions at all post-infection times investigated.
HEFc has good antiviral activity against MAYV, acting directly on the viral particles. This plant extract possesses an excellent and promising potential for developing effective herbal antiviral drugs.
马亚罗热是一种被忽视的热带病。马亚罗病毒（MAYV）的主要传播区域是亚马逊雨林，位于难以到达的偏远地区，药品稀缺。因此，该地区的人们使用植物作为治疗各种疾病的替代方法。Fridericia chica 是热带地区的特有植物，在传统医学中用于治疗发热、不适、炎症和乙型肝炎等传染病。然而，其抗病毒活性知之甚少。
本研究旨在研究 Fridericia chica 叶的水醇提取物（HEFc）在哺乳动物细胞中抗 MAYV 的活性及其可能的作用机制。
使用 Vero 细胞系研究 HEFc 对 MAYV 的抗病毒活性。通过 3-(4,5-二甲基-2-噻唑基)-2,5-二苯基-2H-四唑溴盐（MTT）测定法评估提取物的细胞毒性和抗病毒活性。通过空斑形成单位（PFU）法确认整体抗病毒活性。然后，使用标准实验程序在 Vero 细胞中确定 HEFc 对 MAYV 增殖动力学、病毒吸附、渗透和渗透后以及其杀病毒活性的影响。
HEFc 在非细胞毒性浓度下对 Vero 细胞中的病毒感染具有作用，并且在剂量依赖性和选择性方式下，在上清液中未检测到病毒粒子。HEFc 抑制 MAYV 在病毒复制周期的早期和晚期。该提取物在低浓度下表现出显著的杀病毒活性，并且不影响吸附或病毒内化阶段。此外，HEFc 在所有研究的感染后时间点都减少了病毒粒子。
HEFc 对 MAYV 具有良好的抗病毒活性，直接作用于病毒粒子。这种植物提取物具有开发有效草药抗病毒药物的巨大潜力。
