Design of LVFFARK and LVFFARK-Functionalized Nanoparticles for Inhibiting Amyloid beta-Protein Fibrillation and Cytotoxicity
Design of LVFFARK and LVFFARK-Functionalized Nanoparticles for Inhibiting Amyloid beta-Protein Fibrillation and Cytotoxicity
复制标题
用于抑制淀粉样蛋白纤维化和细胞毒性的 LVFFARK 和 LVFFARK 功能化纳米颗粒的设计
DOI：
10.1021/acsami.5b00915
复制
发表时间：
2015
影响因子：
9.5
通讯作者：
Sun Yan
中科院分区：
文献类型：
--
作者：
Xiong Neng;Dong Xiao-Yan;Zheng Jie;Liu Fu-Feng;Sun Yan
淀粉样β蛋白（Aβ）聚集成淀粉样寡聚体和原纤维在病理上与阿尔茨海默病（AD）有关。因此，抑制Aβ聚集对于预防和治疗AD至关重要，但开发能够抑制Aβ原纤维形成的强效药物已经提出了重大挑战。在此，我们通过将两个带正电荷的残基R和K引入Aβ17-21的中心疏水片段（LVFFA），设计了Ac-LVFFARK-NH 2（LK 7），并通过广泛的物理、生物物理和生物学分析来检测其对Aβ42聚集和细胞毒性的抑制作用。观察到LK 7以剂量依赖性方式抑制Aβ42纤维形成，但其强自组装特性也导致高细胞毒性。为了防止由LK 7的自组装引起的细胞毒性，然后将肽缀合到聚（乳酸-共-乙醇酸）（PLGA）纳米颗粒（NPs）的表面以制造纳米尺寸的抑制剂，LK 7 @PLGA-NPs。发现LK 7 @ PLGA-NP具有很小的细胞毒性，因为缀合在NP上的LK 7的自组装被完全抑制。LK 7 @PLGA-NPs在20 μg/mL的低浓度下对Aβ42聚集有明显的抑制作用，并显著降低了其细胞毒性。在相同的肽浓度下，游离的LK 7显示出很小的抑制作用。认为几种协同效应促成了LK7@PLGA-NPs的强抑制能力，包括通过抑制LK 7自组装引起的Aβ42和LK7@PLGA-NPs之间的相互作用增强，限制Aβ 42的构象变化，从而将Aβ42聚集重新定向为非结构化的、非途径聚集体。基于实验观察，提出了LK 7和LK 7 @PLGA-NPs抑制Aβ42聚集的作用机制。这项工作为设计和开发针对Aβ聚集和细胞毒性的有效NP抑制剂提供了新的见解。
Aggregation of amyloid β-protein (Aβ) into amyloid oligomers and fibrils is pathologically linked to Alzheimer’s disease (AD). Hence, the inhibition of Aβ aggregation is essential for the prevention and treatment of AD, but the development of potent agents capable of inhibiting Aβ fibrillogenesis has posed significant challenges. Herein, we designed Ac-LVFFARK-NH2(LK7) by incorporating two positively charged residues, R and K, into the central hydrophobic fragment of Aβ17–21 (LVFFA) and examined its inhibitory effect on Aβ42 aggregation and cytotoxicity by extensive physical, biophysical, and biological analyses. LK7 was observed to inhibit Aβ42 fibrillogenesis in a dose-dependent manner, but its strong self-assembly characteristic also resulted in high cytotoxicity. In order to prevent the cytotoxicity that resulted from the self-assembly of LK7, the peptide was then conjugated to the surface of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) to fabricate a nanosized inhibitor, LK7@PLGA-NPs. It was found that LK7@PLGA-NPs had little cytotoxicity because the self-assembly of the LK7 conjugated on the NPs was completely inhibited. Moreover, the NPs-based inhibitor showed remarkable inhibitory capability against Aβ42 aggregation and significantly alleviated its cytotoxicity at a low LK7@PLGA-NPs concentration of 20 μg/mL. At the same peptide concentration, free LK7 showed little inhibitory effect. It is considered that several synergetic effects contributed to the strong inhibitory ability of LK7@PLGA-NPs, including the enhanced interactions between Aβ42 and LK7@PLGA-NPs brought on by inhibiting LK7 self-assembly, restricting conformational changes of Aβ42, and thus redirecting Aβ42 aggregation into unstructured, off-pathway aggregates. The working mechanisms of the inhibitory effects of LK7 and LK7@PLGA-NPs on Aβ42 aggregation were proposed based on experimental observations. This work provides new insights into the design and development of potent NPs-based inhibitors against Aβ aggregation and cytotoxicity.