Silva Amélia M, Silva Sandra C, Soares Jorge P, Martins-Gomes Carlos, Teixeira João Paulo, Leal Fernanda, Gaivão Isabel
Department of Biology and Environment, University of Trás-os-Montes e Alto Douro (ECVA, UTAD), Quinta de Prados, 5001-801 Vila Real, Portugal.
Centre for the Research and Technology of Agro-Environmental and Biological Sciences, (CITAB-UTAD), Quinta de Prados, 5001-801 Vila-Real, Portugal.
Plants (Basel). 2019 Nov 29;8(12):556. doi: 10.3390/plants8120556.
L. leaf extracts and herbal infusions are used worldwide due to the health benefits that are attributed to its use, including anti-neoplastic, anti-aging, neuro-protection, antioxidant and others. The aim of this study was to evaluate the effect of an aqueous extract on HepG2 cell viability, genotoxicity and DNA protection against paraquat-induced oxidative damage. Exposure to paraquat (PQ), over 24 h incubation at 1.0 and 1.5 µM, did not significantly reduce cell viability but induced concentration and time-dependent oxidative DNA damage. leaf extract produced dose-dependent cytotoxicity (IC = 540.8 ± 40.5 µg/mL at 24 h exposure), and short incubations (1 h) produced basal and oxidative DNA damage (>750 and 1500 µg/mL, respectively). However, lower concentrations (e.g., 75 µg/mL) of leaf extract were not cytotoxic and reduced basal DNA damage, indicating a protective effect at incubations up to 4 h. On the other hand, longer incubations (24 h) induced oxidative DNA damage. Co-incubation of HepG2 cells for 4 h, with leaf extract (75 µg/mL) and PQ (1.0 or 1.5 µM) significantly reduced PQ-induced oxidative DNA damage. In conclusion, the consumption of leaf extract for long periods at high doses/concentrations is potentially toxic; however, low doses protect the cells against basal oxidative damage and against environmentally derived toxicants that induce oxidative DNA damage.
由于其使用所带来的健康益处，包括抗肿瘤、抗衰老、神经保护、抗氧化等，[植物名称]叶提取物和草药浸剂在全球范围内被广泛使用。本研究的目的是评估水提取物对HepG2细胞活力、遗传毒性以及对百草枯诱导的氧化损伤的DNA保护作用。在1.0和1.5 μM浓度下孵育24小时，百草枯（PQ）暴露并未显著降低细胞活力，但诱导了浓度和时间依赖性的氧化性DNA损伤。[植物名称]叶提取物产生剂量依赖性细胞毒性（24小时暴露时IC = 540.8 ± 40.5 μg/mL），短时间孵育（1小时）产生基础和氧化性DNA损伤（分别>750和1500 μg/mL）。然而，较低浓度（例如75 μg/mL）的[植物名称]叶提取物无细胞毒性，并减少了基础DNA损伤，表明在长达4小时的孵育中具有保护作用。另一方面，较长时间孵育（24小时）诱导了氧化性DNA损伤。将HepG2细胞与[植物名称]叶提取物（75 μg/mL）和PQ（1.0或1.5 μM）共同孵育4小时，显著降低了PQ诱导的氧化性DNA损伤。总之，高剂量/高浓度长期食用[植物名称]叶提取物可能具有毒性；然而，低剂量可保护细胞免受基础氧化损伤以及免受诱导氧化性DNA损伤的环境毒物的影响。
