Department of Biochemistry, Faculty of Biological Sciences, North Tehran Branch, Islamic Azad University, Tehran, Iran.
Department of Biology, Faculty of Food Industry & Agriculture, Standard Research Institute, Karaj, Iran.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Oct 5;278:121372. doi: 10.1016/j.saa.2022.121372. Epub 2022 May 11.
In this study, the acceleratory effect of magnesium oxide nanoparticles (MgO NPs) on the amyloid fibrillization of human tau protein, a major protein involved in the onset of Alzheimer's disease (AD) was investigated. The MgO NPs were fabricated through laser ablation synthesis in solution (LASiS), well-characterized, and explored further for tau aggregation and relevant neurotoxicity by different assays. The results showed that the MgO NPs have a size of around 30 nm, a hydrodynamic radius of 57.09 nm, and a zeta potential of -18.06 mV. The data from ThT and ANS fluorescence-based assays along with circular dichroism (CD) spectroscopy clearly indicated that MgO NPs could significantly promote tau fibrillization, concentration-dependently. Considering the acceleratory effect of MgO NPs against tau fibrillization, cellular assays including cell viability, reactive oxygen species (ROS), and caspase-3 assays indicated that the neurotoxicity of tau amyloid fibrils formed with MgO NPs was higher than that of tau samples aged alone against N2a neuron-like cells. Therefore, it was concluded that the interaction of MgO NPs with tau can lead to acceleration of tau aggregation and underlying neurotoxicity. This study, then can provide useful information about the direct effect of MgO NPs against memory proteins and subsequent adverse effects.
在这项研究中，研究了氧化镁纳米粒子（MgO NPs）对人tau 蛋白淀粉样纤维形成的加速作用，tau 蛋白是阿尔茨海默病（AD）发病的主要蛋白之一。MgO NPs 通过溶液中的激光烧蚀合成（LASiS）制备，经过充分表征，并通过不同的测定方法进一步探索了 tau 聚集和相关神经毒性。结果表明，MgO NPs 的粒径约为 30nm，水动力半径为 57.09nm，zeta 电位为-18.06mV。ThT 和 ANS 荧光测定以及圆二色性（CD）光谱的结果清楚地表明，MgO NPs 可以显著促进 tau 的纤维形成，且具有浓度依赖性。考虑到 MgO NPs 对 tau 纤维形成的加速作用，细胞实验包括细胞活力、活性氧（ROS）和 caspase-3 测定表明，与单独老化的 tau 样品相比，形成的 tau 淀粉样纤维与 MgO NPs 的相互作用对 N2a 神经元样细胞的神经毒性更高。因此，可以得出结论，MgO NPs 与 tau 的相互作用可导致 tau 聚集加速和潜在的神经毒性。这项研究为 MgO NPs 对记忆蛋白的直接作用及其随后的不良影响提供了有用的信息。
