Center for Neuroscience, Faculty of Science, Mahidol University, Bangkok, Thailand.
Interdisciplinary Graduate Program in Genetic Engineering, Kasetsart University, Bangkok, Thailand.
PeerJ. 2022 Jul 6;10:e13693. doi: 10.7717/peerj.13693. eCollection 2022.
(L.) Juss. ex Kunth is a well-known medicinal plant found in tropical and subtropical regions. It contains a broad range of bioactive compounds that exhibit many biological effects, including antidiabetic, antibacterial, and antioxidative activities. However, the effect of natural peptides from against cancer progression and free radical production is unknown. This study aims to evaluate the cytotoxic, anti-metastatic, and antioxidative activities of natural peptides from on A549 cells.
The natural peptides were extracted from the flower of using the pressurized hot water extraction (PHWE) method, followed by size exclusion chromatography and solid-phase extraction-C18. The cytotoxic and anti-metastatic effects of natural peptides were evaluated using MTT and transwell chamber assays, respectively. The free radical scavenging activity of natural peptides was determined using ABTS, DPPH, and FRAP assays. The cells were pretreated with the IC dosage of natural peptides and stimulated with LPS before analyzing intracellular reactive oxygen species (ROS) and proteomics.
Natural peptides induced cell toxicity at a concentration of less than 1 ng/ml and markedly reduced cell motility of A549 cells. The cells had a migration rate of less than 10% and lost their invasion ability in the treatment condition. In addition, natural peptides showed free radical scavenging activity similar to standard antioxidants and significantly decreased intracellular ROS in the LPS-induced cells. Proteomic analysis revealed 1,604 differentially expressed proteins. The self-organizing tree algorithm (SOTA) clustered the protein abundances into eleven groups. The volcano plot revealed that the cancer-promoting proteins (NCBP2, AMD, MER34, ENC1, and COA4) were down-regulated, while the secretory glycoprotein (A1BG) and ROS-reducing protein (ASB6) were up-regulated in the treatment group.
The anti-proliferative and anti-metastatic activities of natural peptides may be attributed to the suppression of several cancer-promoting proteins. In contrast, their antioxidative activity may result from the up-regulation of ROS-reducing protein. This finding suggests that natural peptides from are viable for being the new potential anti-cancer and antioxidative agents.
（L.）Juss. ex Kunth 是一种在热带和亚热带地区广泛存在的著名药用植物。它含有多种生物活性化合物，具有多种生物学效应，包括抗糖尿病、抗菌和抗氧化作用。然而，天然肽对癌症进展和自由基产生的影响尚不清楚。本研究旨在评估天然肽对 A549 细胞的细胞毒性、抗转移和抗氧化活性。
使用加压热水提取（PHWE）法从 的花中提取天然肽，然后进行尺寸排阻色谱和固相萃取-C18。使用 MTT 和 Transwell 室测定天然肽的细胞毒性和抗转移作用。使用 ABTS、DPPH 和 FRAP 测定天然肽的自由基清除活性。用 IC 剂量的天然肽预处理细胞，然后用 LPS 刺激，再分析细胞内活性氧（ROS）和蛋白质组学。
天然肽在浓度低于 1ng/ml 时诱导细胞毒性，并显著降低 A549 细胞的迁移率。在治疗条件下，细胞迁移率小于 10%，丧失侵袭能力。此外，天然肽表现出与标准抗氧化剂相似的自由基清除活性，并显著降低 LPS 诱导细胞内的 ROS。蛋白质组学分析显示 1604 种差异表达蛋白。自组织树算法（SOTA）将蛋白丰度聚类成 11 组。火山图显示，促癌蛋白（NCBP2、AMD、MER34、ENC1 和 COA4）下调，而分泌糖蛋白（A1BG）和 ROS 还原蛋白（ASB6）上调。
天然肽的抗增殖和抗转移活性可能归因于几种促癌蛋白的抑制。相反，其抗氧化活性可能是由于 ROS 还原蛋白的上调。这一发现表明， 天然肽具有作为新型潜在抗癌和抗氧化剂的潜力。
