Microglia are brain-resident immune cells that are essential regulators of neuroinflammation and neurodegeneration. When the brain undergoes stress or injury, microglia are activated, a state that is often referred to as disease-associated microglia (DAM). However, microglial activation is not a binary switch; it represents a dynamic process that is shaped by numerous factors, for instance, the type of stimulus, the duration of the stimulus, the environment within the brain, as well as the pathology of the specific disease. Recent research links microglial activation with features of ferroptosis, an iron-dependent type of regulated cell death. To model inflammatory and reactive conditions, human-induced pluripotent stem cell-derived microglia cells (hiMGL) were exposed to different concentrations of cholesterol and ferric citrate, with the focus on two proteomic targets: the fatty acid binding protein-3 (FABP3) and the ferritin protein complex consisting of ferritin light and heavy chain (FTL and FTH1, respectively). Our findings reveal stimulus-specific alterations in the extracellular levels of FABP3, ferritin, MDH1, LDHB, APOE, and FUCA1, suggesting a link between iron metabolism, lipid processing, and microglial function. Additionally, to explore the temporal dynamics of activation, hiMGL were treated with interferon-gamma (IFNG) and lipopolysaccharides (LPS), with samples collected at multiple time points. Time-dependent proteomic shifts were observed, including significant changes in FABP3, MDH1, LDHB, APOE, FUCA1, SPP1, CD44, and LGALS3, reflecting metabolic and functional adaptations during activation. These findings highlight the complex and dynamic nature of microglial activation, supporting a link between ferroptosis and microglial activity.
2025. , p. 18, 5, 1