Glucose transporter 1 critically controls microglial activation through facilitating glycolysis

Area of Science:

• Neuroscience
• Immunology
• Metabolism

Background:

• Microglial activation is implicated in neurodegenerative diseases.
• Proinflammatory microglia rely on glycolysis, which requires high glucose uptake.
• Understanding glucose uptake mechanisms in microglia is crucial for therapeutic intervention.

Purpose of the Study:

• To investigate how glucose uptake is facilitated in activated microglia.
• To determine if inhibiting glucose uptake can control microglial activation and neuroinflammation.

Main Methods:

• Microglial cell lines (BV2, B6M7) and primary microglia were treated with LPS+IFNγ or IL-4.
• Glucose transporter (GLUT) expression was analyzed via PCR and Western blot.
• Glucose uptake was inhibited using a GLUT1-specific inhibitor (STF31), and metabolic profiles were assessed.
• Inflammatory gene and protein expression were measured, and in vivo efficacy was tested in a mouse model of retinal degeneration.

Main Results:

• GLUT1 was the most highly expressed glucose transporter in microglia, with increased expression under inflammatory conditions.
• STF31 treatment dose-dependently reduced microglial glucose uptake and suppressed extracellular acidification rate.
• STF31 inhibited the upregulation of key inflammatory cytokines (TNFα, IL-1β, IL-6, CCL2) in LPS+IFNγ-activated microglia.
• In vivo administration of STF31 reduced microglial activation and retinal degeneration in a mouse model.

Conclusions:

• Microglial glucose uptake is primarily mediated by GLUT1, especially during inflammation.
• Targeting GLUT1 represents a promising therapeutic strategy for controlling neuroinflammation and mitigating neurodegeneration.