Abnormal misfolding and aggregation of amyloid peptides into amyloid fibrils are common and critical pathological events in many neurodegenerative diseases. Most inhibitors or drugs have been developed to prevent amyloid aggregation of a specific peptide, showing sequence-dependent inhibition mechanisms. It is more challenging to develop or discover inhibitors capable of preventing the aggregation of two or more different amyloid peptides. Genistein, a major phytoestrogen in soybean, has been widely used as an anti-inflammation and cerebrovascular drug due to its antioxidation and antiacetylcholinesterase effects. Herein, we examine the inhibitory effects of genistein on the aggregation of amyloid-β (Aβ, associated with Alzheimer’s disease) and human islet amylin (hIAPP, associated with type 2 diabetes) and Aβ- and hIAPP-induced neurotoxicity using a combination of experimental and computational approaches. Collective experimental results from thioflavin T (ThT), atomic force microscopy (AFM), and circular dichroism (CD) demonstrate that genistein shows strong inhibition ability to prevent the conformational transition of both Aβ and hIAPP monomers to β-sheet structures, thus reducing final amyloid fibrillization from Aβ and hIAPP monomer aggregation by 40–63%. Further 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), and large unilamellar vesicle (LUV) assays show that genistein helps to increase cell viability, decrease cell apoptosis, and reduce cell membrane leakage, where the cell protection effect of genistein is likely correlated with its reduced membrane leakage. Comparative molecular dynamics (MD) simulations reveal that genistein prefers to bind the β-sheet groove, a common structural motif of amyloid fibrils, of both Aβ and hIAPP oligomers to interfere with their self-aggregation. This work for the first time demonstrates genistein as a dual inhibitor of Aβ and hIAPP aggregation. Further structural optimization and refinement of genistein may generate a series of effective sequence-independent inhibitors against the aggregation and toxicity of different amyloid peptides.

中文翻译：

---

Genistein：淀粉样蛋白β和人类胰岛胰岛淀粉样多肽肽的双重抑制剂。

在许多神经退行性疾病中，淀粉样蛋白肽的异常折叠错误和聚集成淀粉样蛋白原纤维是常见且关键的病理事件。已经开发出大多数抑制剂或药物来防止特定肽的淀粉样蛋白聚集，表现出依赖序列的抑制机制。开发或发现能够防止两种或更多种不同淀粉样蛋白肽聚集的抑制剂更具挑战性。金雀异黄素是大豆中的主要植物雌激素，由于其抗氧化和抗乙酰胆碱酯酶的作用，已被广泛用作抗发炎和脑血管药物。在本文中，我们研究了染料木黄酮对淀粉样蛋白β（Aβ，与阿尔茨海默氏病有关）和人胰岛胰岛淀粉样多肽（hIAPP，（与2型糖尿病相关）以及Aβ和hIAPP诱导的神经毒性结合使用实验和计算方法。硫代黄素T（ThT），原子力显微镜（AFM）和圆二色性（CD）的集体实验结果表明，染料木黄酮具有强大的抑制能力，可以阻止Aβ和hIAPP单体的构象转变为β-折叠结构，从而减少最终Aβ和hIAPP单体聚集引起的淀粉样蛋白原纤维化40-63％。进一步的3- [4,5-二甲基噻唑-2-基] -2,5-二苯基四唑溴化物（MTT），乳酸脱氢酶（LDH）和大单层囊泡（LUV）分析表明，染料木黄酮有助于增加细胞活力，减少细胞凋亡，并减少细胞膜泄漏，金雀异黄素的细胞保护作用可能与其减少的膜渗漏有关。比较分子动力学（MD）模拟显示，染料木黄酮更喜欢结合Aβ和hIAPP低聚物的β-片状凹槽（淀粉样蛋白原纤维的常见结构基序）来干扰它们的自聚集。这项工作首次证明了染料木黄酮是Aβ和hIAPP聚集的双重抑制剂。金雀异黄素的进一步结构优化和完善可以产生一系列有效的序列独立抑制剂，以抵抗不同淀粉样肽的聚集和毒性。这项工作首次证明了染料木黄酮是Aβ和hIAPP聚集的双重抑制剂。金雀异黄素的进一步结构优化和完善可以产生一系列有效的序列独立抑制剂，以抵抗不同淀粉样肽的聚集和毒性。这项工作首次证明了染料木黄酮是Aβ和hIAPP聚集的双重抑制剂。金雀异黄素的进一步结构优化和改进可以产生一系列有效的序列独立抑制剂，以抵抗不同淀粉样肽的聚集和毒性。