Figure 3. Quantification of Oil Red O⁺ LLC in the pia mater and distinct regions of the brain during aging.

(A–D)(upper). Dark grey areas in the schema indicate brain regions analyzed in young (~3 month-old), middle age (~12 month-old) or old (>18 month-old) mice. (A–D) (middle). Representative photomicrographs of the dorsal and ventral subregions of the lateral ventricles; pia-mater; brain cortex; and striatum of young, middle-aged and old mice, as indicated in the figure. Black arrowheads point Oil Red O⁺ lipid droplets. Excepting 50 μm scale bar in the image of the lateral ventricle wall dorsal subregion of old mice, scale bars in all other images correspond to 20 μm. (A–D) (lower). Graphs show (A) Oil Red O intensity in lipid droplets per mm in dorsal or ventral subregions or in the total area of lateral ventricles;and the number of Oil Red O⁺ LLC per mm in (B) pia mater or per mm² in (C) cortex and (D) striatum. Y, young; M, middle-aged; O, old mice. Data are presented as mean ± SEM (n = 3 mice per group). *p < 0.05, **p < 0.01, ***p < 0.001.