Quantitative assessment of progressive increases in spheroid density in striatum (A), cerebellum (B), and cortex (C) of iPLA2β-KO mice. Brain sections from iPLA2β-KO mice at 4, 8, and 13 months were stained with a rabbit polyclonal ubiquitin antibody, and average spheroid density in each region was determined by image analysis of multiple random fields in each region. Graphs show mean spheroid density at each age. Error bars indicate SD.