Sevoflurane exposure induces neurotoxicity by regulating mitochondrial function of microglia due to NAD insufficiency

Area of Science:

• Neuroscience
• Immunology
• Anesthesiology

Background:

• Sevoflurane, a common anesthetic, can cause neurotoxicity in developing neurons.
• Microglia, the CNS immune cells, are activated by sevoflurane, releasing inflammatory cytokines.
• This activation impairs microglial phagocytosis, hindering the clearance of damaged neurons.

Purpose of the Study:

• To investigate the mechanism of sevoflurane-induced neurotoxicity.
• To understand the role of microglia and mitochondrial function in this process.

Main Methods:

• In vitro exposure of developmental neurons and microglia to sevoflurane.
• Analysis of microglial activation, cytokine release, and phagocytic activity.
• Assessment of mitochondrial metabolism, ATP, and NAD levels in microglia.

Main Results:

• Sevoflurane exposure activated microglia and increased proinflammatory cytokine secretion.
• Microglial phagocytic function was significantly inhibited following sevoflurane treatment.
• Sevoflurane impaired microglial mitochondrial metabolism, leading to NAD deficiency and reduced energy production.
• Impaired mitochondrial function prevented microglia from clearing damaged neurons.

Conclusions:

• Sevoflurane-induced neurotoxicity in developing neurons is mediated by impaired microglial function.
• Mitochondrial dysfunction and subsequent NAD deficiency in microglia are key mechanisms underlying this neurotoxicity.
• These findings reveal a novel pathway for sevoflurane neurotoxicity, highlighting the importance of microglial bioenergetics.