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Surface-Directed Structural Transition of Amyloidogenic Aggregates and the Resulting Neurotoxicity.

ABSTRACT: The transition of amyloidogenic species into ordered structures (i.e., prefibrillar oligomers, protofibrils, mature fibrils, and amyloidogenic aggregates) is closely associated with many neurodegenerative disease pathologies. It is increasingly appreciated that the liquid-solid interface contributes to peptide aggregation under physiological conditions. However, much remains to be explored on the molecular mechanism of surface-directed amyloid formation. We herein demonstrate that physical environmental conditions (i.e., negatively charged surface) affect amyloid formation. Nontoxic amyloid aggregates quickly develop into intertwisting fibrils on a negatively charged mica surface. These fibrillar structures show significant cytotoxicity on both neuroblastoma cell-lines (SH-SY5Y) and primary neural stem cells. Our results suggest an alternative amyloid development pathway, following which A? peptides form large amyloidogenic aggregates upon stimulation, and later transit into neurotoxic fibrillar structures while being trapped and aligned by a negatively charged surface. Conceivably, the interplay between chemical and physical environmental conditions plays important roles in the development of neurodegenerative diseases.

SUBMITTER: Chen H

PROVIDER: S-EPMC7034003 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Surface-Directed Structural Transition of Amyloidogenic Aggregates and the Resulting Neurotoxicity.

Chen Hao H Sun Dan D Tian Yin Y Fan Haiming H Liu Yonggang Y Morozova-Roche Ludmilla A LA Zhang Ce C

ACS omega 20200206 6

The transition of amyloidogenic species into ordered structures (i.e., prefibrillar oligomers, protofibrils, mature fibrils, and amyloidogenic aggregates) is closely associated with many neurodegenerative disease pathologies. It is increasingly appreciated that the liquid-solid interface contributes to peptide aggregation under physiological conditions. However, much remains to be explored on the molecular mechanism of surface-directed amyloid formation. We herein demonstrate that physical envir ...[more]

PMID: 32095707

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Dataset Information

Surface-Directed Structural Transition of Amyloidogenic Aggregates and the Resulting Neurotoxicity.

Publications

Surface-Directed Structural Transition of Amyloidogenic Aggregates and the Resulting Neurotoxicity.

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