Microglial lipid accumulation is a target for lipid peroxidation injury and mitochondrial oxidative stress in white matter lesions. (A) Example of lesion associated Iba1+ microglia (blue) with varying degrees of lipid peroxidation injury, visualized with 4-hydroxynonenol (4-HNE; red), and mitochondrial oxidative stress, visualized with Tom20 (green). Insets of cells 1 and 2 are shown at higher magnification below together with orthogonal views. Scale bars, 30 μm. (B) The density and percentage of DM were similar in CMI and nCMI cases. (C) The density and percentage of DM in CMI cases was significantly higher than nondegenerative microglia (−DM). (D to F) The density and percentage of DM in CMI cases that labeled for 4-HNE (D), TOM20 (E) and both 4-HNE and TOM20 (F) was significantly higher compared to nondegenerative microglia (−DM). Student’s t-test, ****p<0.0001 in C to F.