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Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils
Published on: September 28, 2019
Fibril fragmentation enhances amyloid cytotoxicity
Wei-Feng Xue1, Andrew L Hellewell, Walraj S Gosal
1Astbury Centre for Structural Molecular Biology, Institute of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom.
The Journal of Biological Chemistry
|October 8, 2009
Summary
Shorter amyloid fibrils are more toxic to cells than longer ones. Fragmentation increases amyloid fibril load and enhances their cytotoxic potential, impacting amyloid disease progression.
Area of Science:
- Biochemistry
- Cell Biology
- Biophysics
Background:
- Amyloid diseases involve protein fibril formation.
- Cellular responses to amyloid fibrils are not fully understood.
- Physical properties of fibrils, like length, may influence cellular effects.
Purpose of the Study:
- To investigate how fragmenting amyloid fibrils affects their structure and biological activity.
- To determine the role of fibril length in amyloid cytotoxicity.
- To understand the impact of fragmentation on amyloid seeding and membrane disruption.
Main Methods:
- Systematic fragmentation of amyloid fibrils.
- Analysis of structural and physical properties of fragmented fibrils.
- Assessment of membrane disruption and cell viability assays.
Main Results:
- Fibril fragmentation correlates with increased seeding ability.
- Shorter amyloid fibrils exhibit enhanced membrane disruption and reduced cell viability compared to longer fibrils.
- Fragmentation increases fibril load and generates species with altered biological properties.
Conclusions:
- Fibril length is a critical factor in amyloid cytotoxicity.
- Fragmentation can increase amyloid load and create more potent cytotoxic species.
- Understanding fibril dimensions is crucial for comprehending amyloid disease mechanisms.
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