Nerve Growth Factor modulates LPS - induced microglial glycolysis and inflammatory responses

Area of Science:

• Neuroscience
• Immunology
• Cell Biology

Background:

• Microglia are key immune cells in the central nervous system, regulating neuroinflammation and tissue repair.
• Aberrant microglial activation contributes significantly to neurodegenerative disease progression.
• Understanding endogenous regulators of microglial neuroinflammation is crucial.

Purpose of the Study:

• To investigate the role of Nerve Growth Factor (NGF) in modulating microglial inflammatory responses.
• To elucidate the molecular mechanisms underlying NGF's effects on microglia.

Main Methods:

• Primary mouse microglia were treated with lipopolysaccharide (LPS) and NGF.
• Investigated pro-inflammatory cytokine and nitric oxide (NO) production.
• Analyzed activation of NF-κB and JNK signaling pathways via Toll-like receptor 4 (TLR4).
• Assessed microglial glycolytic activity, including glucose uptake and key enzyme expression (Pfkβ3, Ldhα).
• Utilized 2-deoxy-D-glucose (2DG) to inhibit glycolysis.

Main Results:

• NGF, via its receptor TrkA, suppressed LPS-induced pro-inflammatory cytokine and NO production.
• NGF inhibited TLR4-mediated activation of NF-κB and JNK pathways.
• NGF attenuated LPS-enhanced microglial glycolysis, evidenced by reduced glucose uptake and altered enzyme expression.
• Glycolysis inhibition using 2DG mimicked NGF's effect by reducing LPS-induced cytokine production.

Conclusions:

• NGF effectively attenuates pro-inflammatory responses in microglia.
• NGF's mechanism involves downregulating inflammatory signaling and glycolytic metabolism.
• NGF represents a potential endogenous factor for regulating microglia-mediated neuroinflammation.