Simvastatin alters M1/M2 polarization of murine BV2 microglia via Notch signaling

Area of Science:

• Neuroimmunology
• Cellular immunology
• Molecular signaling

Background:

• Microglia are key regulators of CNS immune function, with M1/M2 polarization influencing immune responses.
• Statins are known to possess immunomodulatory properties, but their specific effects on microglial polarization require further elucidation.
• Notch signaling is implicated in various cellular processes, including immune cell differentiation and function.

Purpose of the Study:

• To investigate the role of Notch signaling in simvastatin-induced alterations of M1/M2 polarization in murine BV2 microglia.
• To determine whether simvastatin affects M1 and M2 marker expression in microglia.
• To elucidate the involvement of Notch signaling in mediating simvastatin's effects on microglial polarization.

Main Methods:

• BV2 cells were treated with lipopolysaccharide (LPS) and Jagged-1 to induce M1 polarization.
• Simvastatin was administered to assess its effect on M1/M2 marker expression.
• Notch signaling molecules' expression was analyzed, and Notch1 knockdown was performed to evaluate its role.

Main Results:

• LPS and Jagged-1 treatment significantly increased M1 markers, an effect attenuated by simvastatin.
• Simvastatin treatment enhanced M2 markers.
• Simvastatin upregulated Notch signaling molecules, and these effects were abrogated in Notch1-knockdown cells.

Conclusions:

• Simvastatin alters the M1/M2 polarization balance in murine BV2 microglia.
• The observed alterations in microglial polarization by simvastatin are mediated through the Notch signaling pathway.
• These findings highlight a novel mechanism by which statins modulate neuroinflammation.