Extracellular Aβ42 Oligomers Induce ROCK2 Hyperactivation Through Dual Mediation by RhoA and GzmB: Significance of
Changxin Zheng1, Kai Wen1, He Li1
1Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China.
Cells
|August 13, 2026
Summary
Alzheimer's disease involves amyloid-β oligomers damaging brain cells by activating ROCK2. This disrupts the actin cytoskeleton, impairing neurite growth and neuronal survival, offering new therapeutic targets.
Area of Science:
- Neuroscience
- Cell Biology
- Biochemistry
Background:
- Alzheimer's disease (AD) is marked by neurite degeneration and neuronal death.
- Extracellular amyloid-β 1-42 (Aβ42) oligomers disrupt extracellular matrix homeostasis and damage neural cells.
- Aβ42 oligomers binding to integrins reduces neuronal motility, adhesion, and neuritogenesis.
Purpose of the Study:
- To identify molecular switches causing actin cytoskeleton dysfunction in Alzheimer's disease.
- To investigate the cascade of extracellular amyloid-β oligomer-induced actin cytoskeleton dysfunction.
- To understand the role of ROCK2 in Alzheimer's disease pathogenesis.
Main Methods:
- Utilized neuronal and glial cell lines.
- Employed Alzheimer's disease model mice.
- Investigated the RhoA and granzyme B (GzmB) mediated activation of ROCK2.
Main Results:
- Extracellular amyloid-β oligomers induce dual activation of ROCK2 via RhoA and GzmB.
- GzmB-mediated ROCK2 activation is a significant factor in this process.
- ROCK2 hyperactivation leads to actin cytoskeleton dysregulation, defective neuritogenesis, reduced cell survival, and brain cell population disturbances.
Conclusions:
- ROCK2 hyperactivation contributes to Alzheimer's disease pathogenesis by disrupting actin cytoskeleton dynamics.
- Imbalances in ROCK2 activity may impair neuritogenesis and affect brain cell populations.
- Findings offer insights into AD pathogenesis and potential therapeutic targets for ROCK2 modulation.
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