Poststroke dendritic arbor regrowth requires the actin nucleator Cobl.

Area of Science:

• Neuroscience
• Molecular Biology
• Stroke Research

Background:

• Ischemic stroke is a leading cause of death and disability.
• Stroke induces damage to neuronal structures, specifically dendritic arborization in penumbral neurons.
• Excitotoxicity, a consequence of stroke, involves calpain-mediated proteolysis and impacts protein levels.

Purpose of the Study:

• To investigate the role of the actin nucleator Cobl in post-stroke dendritic repair.
• To understand the molecular mechanisms underlying Cobl's involvement in neuronal recovery after ischemic stroke.
• To examine the consequences of Cobl deficiency on dendritic repair in a mouse model.

Main Methods:

• Middle cerebral artery occlusion (MCAO) model in mice to induce ischemic stroke.
• Analysis of dendritic arborization in penumbral neurons.
• Assessment of Cobl levels and mRNA expression post-stroke.
• Comparison of Cobl knockout (KO) mice with wild-type (WT) mice.

Main Results:

• MCAO caused a significant decline in dendritic arborization of penumbral neurons.
• Cobl levels were reduced by stroke and excitotoxicity but rapidly restored via increased mRNA expression.
• Cobl played a critical role in the repair of dendritic arbors in peri-infarct areas between days 2 and 4 post-stroke.
• Cobl KO mice showed no dendritic regrowth during this window, with persistent impairments in penumbral neurons.

Conclusions:

• A potent post-stroke recovery process exists, involving the actin nucleator Cobl.
• Restoration of Cobl levels is crucial for dendritic arbor repair after ischemic stroke.
• Cobl is a key molecular mechanism essential for post-stroke neuronal recovery and functional repair.