High Extracellular Glucose Concentration Drives Palmitate-Induced Toxicity and Metabolic Dysfunction in BV2 Microglia...

Area of Science:

• Neuroimmunology
• Cellular Metabolism
• Neuroinflammation

Background:

• Microglia, the brain's immune cells, respond to lipids like palmitate.
• These responses are influenced by environmental factors, including glucose availability.
• Understanding these interactions is key to brain homeostasis.

Purpose of the Study:

• To investigate how extracellular glucose concentrations affect microglial responses to palmitate.
• To examine the impact of palmitate on inflammatory, metabolic, and phagocytic functions of microglia under varying glucose conditions.

Main Methods:

• BV2 microglial cells were cultured in low glucose (LG) or high glucose (HG) media.
• Cells were exposed to palmitate (100 or 200 µmol/L) or vehicle for 24 hours.
• Assessed cell viability, inflammatory markers, gene expression (lipid/glucose metabolism), oxygen consumption rate (OCR), and glycolytic flux.

Main Results:

• Under HG, palmitate decreased cell viability and increased inflammatory markers, indicating activation.
• Palmitate upregulated lipid metabolism genes but not glucose metabolism genes in both LG and HG.
• Palmitate reduced OCR and glycolytic flux; butyrate did not prevent mitochondrial dysfunction.

Conclusions:

• High glucose exacerbates palmitate-induced stress on BV2 cell viability and inflammatory responses.
• Palmitate impacts microglial metabolism and mitochondrial function, with glucose levels modulating these effects.
• BV2 cells show increased susceptibility to palmitate-induced stress in high glucose environments.