Programa de Pós-Graduação em Ciências Farmacêuticas, Department of Pharmacy, Universidade Estadual de Maringá, Maringá, Paraná, Brazil.
Programa de Pós-Graduação em Genética e Biologia Molecular, Department of General Biology, Universidade Estadual de Londrina, Londrina, Paraná, Brazil.
PLoS One. 2019 Feb 14;14(2):e0212089. doi: 10.1371/journal.pone.0212089. eCollection 2019.
Alzheimer's disease (AD) is the most common form of dementia and has no cure. Therapeutic strategies focusing on the reduction of oxidative stress, modulation of amyloid-beta (Aβ) toxicity and inhibition of tau protein hyperphosphorylation are warranted to avoid the development and progression of AD. The aim of this study was to screen the crude extracts (CEs) and ethyl-acetate fractions (EAFs) of Guazuma ulmifolia, Limonium brasiliense, Paullinia cupana, Poincianella pluviosa, Stryphnodendron adstringens and Trichilia catigua using preliminary in vitro bioassays (acetylcholinesterase inhibition, antioxidant activity and total polyphenol content) to select extracts/fractions and assess their protective effects against Aβ25-35 toxicity in SH-SY5Y cells. The effect of the EAF of S. adstringens on mitochondrial membrane potential, lipid peroxidation, superoxide production and mRNA expression of 10 genes related to AD was also evaluated and the electropherogram fingerprints of EAFs were established by capillary electrophoresis. Chemometric tools were used to correlate the in vitro activities of the samples with their potential to be evaluated against AD and to divide extracts/fractions into four clusters. Pretreatment with the EAFs grouped in cluster 1 (S. adstringens, P. pluviosa and L. brasiliense) protected SH-SY5Y cells from Aβ25-35-induced toxicity. The EAF of S. adstringens at 15.62 μg/mL was able completely to inhibit the mitochondrial depolarization (69%), superoxide production (49%) and Aβ25-35-induced lipid peroxidation (35%). With respect to mRNA expression, the EAF of S. adstringens also prevented the MAPT mRNA overexpression (expression ratio of 2.387x) induced by Aβ25-35, which may be related to tau protein hyperphosphorylation. This is the first time that the neuroprotective effects of these fractions have been demonstrated and that the electropherogram fingerprints for the EAFs of G. ulmifolia, L. brasiliense, P. cupana, P. pluviosa and S. adstringens have been established. The study expands knowledge of the in vitro protective effects and quality control of the evaluated fractions.
阿尔茨海默病（AD）是最常见的痴呆症形式，目前尚无治愈方法。针对氧化应激减少、淀粉样蛋白-β（Aβ）毒性调节和tau 蛋白过度磷酸化抑制的治疗策略是必要的，以避免 AD 的发展和进展。本研究旨在使用初步的体外生物测定（乙酰胆碱酯酶抑制、抗氧化活性和总多酚含量）筛选 Guazuma ulmifolia、Limonium brasiliense、Paullinia cupana、Poincianella pluviosa、Stryphnodendron adstringens 和 Trichilia catigua 的粗提取物（CEs）和乙酸乙酯级分（EAFs），以选择提取物/级分，并评估它们对 SH-SY5Y 细胞中 Aβ25-35 毒性的保护作用。还评估了 S. adstringens 的 EAF 对线粒体膜电位、脂质过氧化、超氧化物产生和与 AD 相关的 10 个基因的 mRNA 表达的影响，并通过毛细管电泳建立了 EAFs 的电泳图谱指纹。化学计量学工具用于将样品的体外活性与它们对抗 AD 的潜在评估相关联，并将提取物/级分分为四个聚类。在 cluster 1（S. adstringens、P. pluviosa 和 L. brasiliense）分组的 EAFs 预处理可保护 SH-SY5Y 细胞免受 Aβ25-35 诱导的毒性。S. adstringens 的 EAF 在 15.62 μg/mL 时能够完全抑制线粒体去极化（69%）、超氧化物产生（49%）和 Aβ25-35 诱导的脂质过氧化（35%）。就 mRNA 表达而言，S. adstringens 的 EAF 还阻止了 Aβ25-35 诱导的 MAPT mRNA 过表达（表达比为 2.387x），这可能与 tau 蛋白过度磷酸化有关。这是首次证明这些级分的神经保护作用，并且建立了 G. ulmifolia、L. brasiliense、P. cupana、P. pluviosa 和 S. adstringens 的 EAF 电泳图谱指纹。该研究扩展了评估级分的体外保护作用和质量控制的知识。
