Laboratory of Animal Physiology, Faculty of Science, University of Yaoundé I, Cameroon.
Laboratory of Natural Substances, Faculty of Science, University of Yaoundé I, Cameroon.
J Ethnopharmacol. 2021 Feb 10;266:113424. doi: 10.1016/j.jep.2020.113424. Epub 2020 Oct 1.
Malaria is a life-threatening health problem worldwide and treatment remains a major challenge. Natural products from medicinal plants are credible sources for better anti-malarial drugs.
This study aimed at assessing the in vitro and in vivo antiplasmodial activities of the hydroethanolic extract of Bridelia atroviridis bark.
The phytochemical characterization of Bridelia atroviridis extract was carried out by High-Performance Liquid Chromatography-Mass spectrometry (HPLC-MS). The cytotoxicity test on Vero cells was carried out using the resazurin-based assay while the in vitro antiplasmodial activity was determined on Plasmodium falciparum (Dd2 strain, chloroquine resistant) using the SYBR green I-based fluorescence assay. The in vivo assay was performed on Plasmodium berghei-infected rats daily treated for 5 days with distilled water (10 mL/kg) for malaria control, 25 mg/kg of chloroquine sulfate for positive control and 50, 100 and 200 mg/kg of B. atroviridis extract for the three test groups. Parasitaemia was daily monitored using 10% giemsa-staining thin blood smears. At the end of the treatment, animals were sacrificed, blood was collected for hematological and biochemical analysis while organs were removed for biochemical and histopathological analyses.
The HPLC-MS analysis data of B. atroviridis revealed the presence of bridelionoside D, isomyricitrin, corilagin, myricetin and 5 others compounds not yet identified. Bridelia atroviridis exhibited good in vitro antiplasmodial activity with the IC evaluated at 8.08 μg/mL and low cytotoxicity with the median cytotoxic concentration (CC) higher than 100 μg/mL. B. atroviridis extract significantly reduced the parasitemia (p < 0.05) with an effective dose-50 (ED-50) of 89 mg/kg. B. atroviridis also prevented anemia, leukocytosis and liver and kidneys impairment by decrease of transaminases, ALP, creatinine, uric acid, and triglycerides concentrations. As well, B. atroviridis extract decreased some pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) levels and significantly improved the anti-inflammatory status (P < 0.01) of infected animals marked by a decrease of IL-10 concentration. These results were further confirmed by the improved of antioxidant status and the quasi-normal microarchitecture of the liver, kidneys and spleen in test groups. Overall, the hydroethanolic bark extract of Bridelia atroviridis demonstrated antimalarial property and justified its use in traditional medicine to manage malaria disease.
疟疾是全球范围内威胁生命的健康问题，治疗仍然是一个主要挑战。药用植物的天然产物是更好的抗疟药物的可信来源。
本研究旨在评估 Bridelia atroviridis 树皮水醇提取物的体外和体内抗疟原虫活性。
通过高效液相色谱-质谱联用（HPLC-MS）对 Bridelia atroviridis 提取物进行植物化学特征描述。使用基于 Resazurin 的测定法进行对 Vero 细胞的细胞毒性试验，而使用基于 SYBR Green I 的荧光测定法在 Plasmodium falciparum（Dd2 株，氯喹抗性）上测定体外抗疟原虫活性。在感染 Plasmodium berghei 的大鼠中进行体内试验，每天用蒸馏水（10 mL/kg）处理 5 天以控制疟疾，用 25 mg/kg 的硫酸氯喹作为阳性对照，用 50、100 和 200 mg/kg 的 B. atroviridis 提取物作为三个试验组。每天使用 10%吉姆萨染色薄血涂片监测寄生虫血症。在治疗结束时，处死动物，采集血液进行血液学和生化分析，同时取出器官进行生化和组织病理学分析。
B. atroviridis 的 HPLC-MS 分析数据显示存在 bridelionoside D、异鼠李糖苷、柯里拉京、杨梅素和其他 5 种尚未鉴定的化合物。Bridelia atroviridis 表现出良好的体外抗疟原虫活性，IC 值评估为 8.08 μg/mL，细胞毒性低，中值细胞毒性浓度（CC）高于 100 μg/mL。B. atroviridis 提取物显著降低了寄生虫血症（p < 0.05），有效剂量 50（ED-50）为 89 mg/kg。B. atroviridis 还通过降低转氨酶、碱性磷酸酶、肌酐、尿酸和甘油三酯浓度来预防贫血、白细胞增多和肝肾功能损害。此外，B. atroviridis 提取物降低了一些促炎细胞因子（TNF-α、IL-1β、IL-6）水平，并显著改善了感染动物的抗炎状态（P < 0.01），IL-10 浓度降低。这些结果通过在试验组中改善抗氧化状态和肝脏、肾脏和脾脏的准正常微观结构得到进一步证实。总体而言，Bridelia atroviridis 的水醇树皮提取物表现出抗疟原虫特性，证明其可用于传统医学来治疗疟疾。
