ABSTRACT

Sida planicaulis is a weed thought to have originated in Brazil, where it is present in abundant quantities, but also this plant is also found in south-central Florida, Indian Ocean Islands, and the Pacific Islands. Sida planicaulis produces neurotoxicity that adversely affects livestock breeding with heavy animal losses and consequent negative impact on Brazil’s economy. The aim of this study was to determine the chemical profile, cytotoxic and genotoxic effects of ethanolic extracts of S. planicaulis collected in winter (leaf extract) and summer (leaf extract and leaf + flower extract) using an in vitro model of human neuroblastoma cell line SH-SY5Y. Phytochemical screening demonstrated the presence of alkaloids, flavonoids, and apolar compounds. Rutin, quercetin, and swainsonine were detected by HPLC and GC/MS, respectively. Phosphorus, potassium, iron, and zinc were the inorganic elements found. Extracts produced cytotoxicity at all concentrations tested (7–4,000 μg/ml) as evidenced by the colorimetric assay [3-(4,5-dimethyl-thiazol-2-yl) −2,5-diphenyl-tetrazolium bromide (MTT)]. Based upon the alkaline comet assay extracts were found to induce genotoxicity at concentrations ranging from 0.437 to 7 μg/ml. DNA damage produced by extracts was affirmed using a modified comet assay with the enzymes Endo III and FPG in a concentration dependent manner. Further, enzyme-modified comet assay showed both oxidized purines and pyrimidines, and consequently oxidative stress was related to genomic instability and cell death. Data suggest that low concentrations of ethanolic extracts of S. planicaulis (different seasons) induced increased DNA damage related to oxidative stress and chemical composition.

摘要

Sida planicaulis是一种被认为起源于巴西的杂草，在那里大量存在，但在佛罗里达州中南部、印度洋群岛和太平洋群岛也发现了这种植物。Sida planicaulis产生神经毒性，对牲畜繁殖产生不利影响，造成大量动物损失，从而对巴西经济产生负面影响。本研究的目的是确定的化学特性，的乙醇提取物的细胞毒性和基因毒性作用S. planicaulis使用收集在冬季（叶提取物）和夏季（叶提取物和叶+花提取物）的体外人神经母细胞瘤细胞系 SH-SY5Y 模型。植物化学筛选证明存在生物碱、黄酮类化合物和非极性化合物。芦丁、槲皮素和苦豆素分别通过 HPLC 和 GC/MS 检测。磷、钾、铁和锌是发现的无机元素。比色测定证明提取物在所有测试浓度 (7–4,000 μg/ml) 下均产生细胞毒性 [3-(4,5-二甲基-噻唑-2-基) -2,5-二苯基-四唑溴化物 (MTT)] . 根据碱性彗星试验，发现提取物在 0.437 至 7 μg/ml 的浓度范围内诱导基因毒性。提取物产生的 DNA 损伤使用改良的彗星试验以浓度依赖的方式使用 Endo III 和 FPG 酶进行确认。此外，酶修饰彗星试验显示氧化嘌呤和嘧啶，因此氧化应激与基因组不稳定性和细胞死亡有关。数据表明，低浓度的乙醇提取物S. planicaulis（不同季节）诱导与氧化应激和化学成分相关的 DNA 损伤增加。