Activin A is a novel chemoattractant for migration of microglial BV2 cells

Area of Science:

• Neuroscience
• Cell Biology
• Immunology

Background:

• Microglia play critical roles in neurodegenerative diseases and CNS injury repair.
• Activin A is a known neurotrophic and neuroprotective factor influencing macrophage/microglia activity.
• The specific impact of Activin A on microglial migration remains largely undetermined.

Purpose of the Study:

• To investigate the role of Activin A in regulating microglial migration.
• To elucidate the signaling pathways involved in Activin A-mediated microglial responses.
• To assess the potential of Activin A as a therapeutic target for CNS conditions.

Main Methods:

• Utilized murine microglial BV2 cells for experiments.
• Assessed cytokine levels using ELISA and protein expression via Western blotting.
• Evaluated cell adhesion with RTCA and migration using transwell chambers and microfluidics.
• Manipulated Smad3 expression through overexpression and knockdown techniques.

Main Results:

• Activin A suppressed nitric oxide and inflammatory cytokine (TNF-α, IL-6) release and mRNA expression.
• Activin A enhanced TGF-β1 production, inhibited adhesion, and promoted wound healing and migration.
• Changes in cell migration and inflammatory markers correlated with N-cadherin and E-cadherin expression.
• Smad3 overexpression mimicked Activin A's pro-migration and anti-inflammatory effects, while knockdown reversed them.

Conclusions:

• Activin A modulates microglial biological behavior, including migration and inflammatory response, through Smad3 signaling.
• These findings highlight Activin A's potential as a therapeutic target for neuroinflammation and glial scar formation.
• The study provides insights into the molecular mechanisms underlying microglial function in the CNS.