Competitive Superiority by Bi-flavonoids to Mono-flavonoids in Inhibiting Amyloid-β Toxicity and Fibrillogenesis through Accumulating Nontoxic Oligomer-like Structures
Polymerization of monomeric amyloid-β peptides (Aβ) into soluble oligomers and insoluble fibrils is one of the major pathways triggering the pathogenesis of Alzheimer’s disease (AD). Using small molecules to prevent the polymerization of Aβ peptides can, therefore, be an effective therapeutic strategy for AD. In this study, we investigated the effects of mono- and bi-flavonoids on Aβ42 toxicity and fibrillogenesis and found that the bi-flavonoid, taiwaniaflavone (TF) effectively and specifically inhibits Aβ toxicity and fibrillogenesis. Compared to TF, the mono-flavonoid apigenin (AP) is less effective and less specific. Our data showed that differential effects of the mono- and bi- flavonoids on Aβ fibrillogenesis correlate with their varying cytoprotective efficacies. We also found that other bi- flavonoids, namely 2',8''- biapigenin, amentoflavone, and sumaflavone, can also effectively inhibit Aβ toxicity and fibrillogenesis, implying that the participation of two mono-flavonoids in a single bi-flavonoid molecule enhanced their activity. Bi- flavonoids, while strongly inhibited Aβ fibrillogenesis, accumulated nontoxic Aβ oligomeric structures, suggesting that these are offpathway- oligomers. Moreover, TF abrogated the toxicity of preformed Aβ oligomers and fibrils, indicating that TF and other bi-flavonoids may also reduce the toxicity of toxic Aβ species. Altogether, our data clearly show that bi-flavonoids, possibly due to the possession of two Aβ binders separated by an appropriate size linker, are likely to be promising therapeutics to suppress Aβ toxicity.
목차
Abstract 1. Introduction 2. Materials and Methods 2.1 Materials 2.2. Preparation of Aβ42 Monomer, Oligomers, and Fibrils 2.3. Cell Culture and Toxicity Assay 2.4. Caspase Activity Assay 2.5. Circular Dichroism (CD) Spectroscopy 2.6. Transmission Electron Microscopy (TEM) 2.7. Detection of Aβ42 Oligomers by Immunoblotting Assay 3. Results 3.1. TF Specifically and Potently Inhibited Aβ Toxicity 3.2. Kinetic Studies on Aβ Fibrillogenesis/Fibril Destablization in the Presence of TF or AP 3.3. TF Inhibits Aβ42 Structural Transformation 3.4. TF Accumulated Oligomeric Aβ Structures 3.5. TF is Cytoprotective Against Preformed Aβ42 Oligomers and Fibrils 3.6. Effects of Other Related Bi-flavonoids in Aβ Toxicity and Fibrillogenesis 4. Discussion References
Merlin Jayalal .L .P [ Department of Biochemistry, Bharathidasan college of Arts and Science, Ellispettai, Erode-638116, Tamilnadu, India ]
Corresponding author
조선대학교 기초과학연구원 [The Natural Science Research Institute of Chosun]
설립연도
2008
분야
자연과학>자연과학일반
소개
본 연구원은 기초과학을 진흥하기 위한 연구·교육 및 그 보급을 목적으로 한다. 이 목적을 달성하기 위하여 다음 각 호의 사업을 수행한다.
1. 기초과학 제 분야에 관한 조사와 연구
2. 기초과학에 관한 학술행사(학술대회, 학술세미나, 심포지엄, 초청강연회 등) 개최
3. 학문후속세대 및 일반인을 위한 기초과학 교육
4. 기관지『조선자연과학논문지』 발간
5. 『자연과학연구총서』, 『자연과학번역총서』 등 단행본 발간
6. 기타 본 연구원의 목적과 관련된 사업
간행물
간행물명
통합자연과학논문집(구 조선자연과학논문집) [Journal of Integrative Natural Science]