Department of Pharmacognosy, Faculty of Pharmacy, Medical University of Lodz, 1 Muszynskiego St., 90-151 Lodz, Poland.
Microbiota Lab, Centre for Preclinical Studies, Department of Pharmacognosy and Molecular Basis of Phytotherapy, Medical University of Warsaw, 1 Banacha St., 02-097 Warsaw, Poland.
Molecules. 2022 May 23;27(10):3357. doi: 10.3390/molecules27103357.
The leaves of are polyphenol-rich traditional medicines used to treat inflammation-related diseases. The present study aimed to optimise the solvent for the effective recovery of active leaf components through simple direct extraction and verify the biological effects of the selected extract in a model of human neutrophils ex vivo. The extracts were comprehensively standardised, and forty-one individual polyphenols, representing salicylates, catechins, procyanidins, phenolic acids, and flavonoids, were identified by UHPLC-PDA-ESI-MS. The chosen methanol-water (75:25, /) extract (ME) was obtained with the highest extraction yield and total phenolic levels (397.9 mg/g extract's dw), including 98.9 mg/g salicylates and 299.0 mg/g non-salicylate polyphenols. In biological tests, ME revealed a significant and dose-dependent ability to modulate pro-oxidant and pro-inflammatory functions of human neutrophils: it strongly reduced the ROS level and downregulated the release of pro-inflammatory cytokines and tissue remodelling enzymes, especially IL-1β and elastase 2, in cells stimulated by MLP, LPS, or MLP + cytochalasin B. The extracts were also potent direct scavengers of in vivo relevant oxidants (O, OH, and HO) and inhibitors of pro-inflammatory enzymes (cyclooxygenase-2, hyaluronidase, and lipoxygenase). The statistically significant correlations between the tested variables revealed the synergic contribution of individual polyphenols to the observed effects and indicated them as useful active markers for the standardisation of the extract/plant material. Moreover, the safety of ME was confirmed in cytotoxicity tests. The obtained results might partially explain the ethnomedicinal application of leaves and support the usage of the standardised leaf extract in the adjuvant treatment of oxidative stress and inflammation-related chronic diseases.
是一种富含多酚的传统药用植物叶子，用于治疗与炎症相关的疾病。本研究旨在通过简单的直接提取优化有效回收活性叶成分的溶剂，并在人中性粒细胞体外模型中验证所选提取物的生物学效应。提取物进行了全面标准化，通过 UHPLC-PDA-ESI-MS 鉴定了 41 种单体多酚，包括水杨酸酯、儿茶素、原花青素、酚酸和类黄酮。选择的甲醇-水（75:25，/）提取物（ME）具有最高的提取产率和总酚含量（397.9 mg/g 提取物的干重），其中包括 98.9 mg/g 的水杨酸酯和 299.0 mg/g 的非水杨酸酯多酚。在生物学测试中，ME 显示出显著的、剂量依赖性的调节人中性粒细胞促氧化剂和促炎功能的能力：它强烈降低 ROS 水平，下调由 MLP、LPS 或 MLP +细胞松弛素 B 刺激的细胞中促炎细胞因子和组织重塑酶（特别是 IL-1β 和弹性蛋白酶 2）的释放。提取物也是体内相关氧化剂（O、OH 和 HO）的有效直接清除剂和促炎酶（环加氧酶-2、透明质酸酶和脂氧合酶）的抑制剂。测试变量之间的统计显著相关性表明了单体多酚对观察到的效应的协同贡献，并将其作为提取物/植物材料标准化的有用活性标志物。此外，ME 的细胞毒性测试证实了其安全性。获得的结果可能部分解释了 叶子的民间医学应用，并支持将标准化的叶提取物用于辅助治疗氧化应激和炎症相关的慢性疾病。
