Neuropeptide Y protects cerebral cortical neurons by regulating microglial immune function

Area of Science:

• Neuroscience
• Immunology
• Cell Biology

Background:

• Reactive microglia contribute to neuroinflammation and excitotoxicity.
• Neuropeptide Y (NPY) exhibits neuroprotective properties.
• Microglial activation elevates pro-inflammatory cytokines and N-methyl-D-aspartate (NMDA) currents.

Purpose of the Study:

• To investigate the role of Neuropeptide Y in modulating microglial activation and its downstream effects on cortical neurons.
• To elucidate the involvement of the Neuropeptide Y Y1 receptor in these neuroprotective mechanisms.

Main Methods:

• Primary rat cortical microglia were treated with lipopolysaccharide (LPS).
• Cytokine levels (interleukin-1β, tumor necrosis factor-α) and mRNA expression were measured.
• Primary rat cortical neurons were exposed to conditioned medium from LPS-treated microglia.
• N-methyl-D-aspartate current (I NMDA) in neurons was recorded.
• The effects of Neuropeptide Y and its Y1 receptor antagonist (BIBP3226) were assessed.

Main Results:

• LPS treatment increased interleukin-1β and tumor necrosis factor-α in microglia.
• LPS-induced microglial conditioned medium enhanced neuronal I NMDA.
• Neuropeptide Y suppressed LPS-induced cytokine production and normalized neuronal I NMDA.
• The Neuropeptide Y Y1 receptor antagonist BIBP3226 abolished the effects of Neuropeptide Y.

Conclusions:

• Neuropeptide Y inhibits microglial reactivity, reducing pro-inflammatory cytokine release.
• Neuropeptide Y protects cortical neurons from excitotoxicity by decreasing I NMDA.
• The Neuropeptide Y Y1 receptor mediates these neuroprotective effects against inflammation-induced neuronal damage.