원문정보
초록
영어
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
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