A Breakdown in Metabolic Reprogramming Causes Microglia Dysfunction in Alzheimer's Disease.

Area of Science:

• Neuroimmunology
• Metabolic pathways in neurodegeneration
• Alzheimer's disease pathogenesis

Background:

• Reactive microglia are a hallmark of Alzheimer's disease (AD), but their precise role remains elusive.
• Understanding microglial function is critical for developing effective AD therapies.

Purpose of the Study:

• To investigate the metabolic changes in microglia during Alzheimer's disease progression.
• To explore the impact of metabolic reprogramming on microglial immune responses in AD.
• To evaluate the therapeutic potential of metabolic modulation for AD treatment.

Main Methods:

• Metabolic profiling and genome-wide RNA sequencing were employed.
• Multiphoton microscopy was used to visualize microglial activity in AD mouse models (5XFAD).
• Intervention with recombinant interferon-gamma was tested to assess metabolic and functional recovery.

Main Results:

• Amyloid-beta exposure induced acute microglial inflammation via mTOR-HIF-1α-dependent metabolic reprogramming (oxidative phosphorylation to glycolysis).
• Chronic activation led to metabolic defects and impaired microglial immune functions (cytokine secretion, phagocytosis) in 5XFAD mice.
• Metabolic boosting with interferon-gamma reversed glycolytic defects and enhanced microglial inflammatory functions, mitigating AD pathology.

Conclusions:

• Microglial metabolic reprogramming is a key factor in Alzheimer's disease pathogenesis.
• Defective microglial metabolism contributes to diminished immune responses in chronic AD.
• Targeting microglial metabolism represents a promising therapeutic strategy for Alzheimer's disease.