Figure 7.

Polyphenols from olive leaf extract induce the upregulation of PLP in different brain regions (hippocampus, cortex, and white matter). (a) Representative immunohistochemical pictures show staining with anti-PLP antibody in paraffin-embedded sections of the brain tissue obtained from DA rats: (A–C) untreated, (D–F) with induced EAE and the second attack (on the 20^th day postinduction), (G–I) with induced EAE and treated with polyphenols till the 20^th day postinduction, (J–L) with induced EAE and the second remission (on the 30^th day postinduction), and (M–O) with induced EAE and treated with polyphenols on the 30^th day postinduction. (b) PLP immunoreactivity in different brain regions. The immunohistochemical staining quantification was performed using Cell F v3.1 software analysis (12 ROI/4 μm slice × 3 slices/rat × 5 rats/group) of representative cortex photomicrographs (C, G, K, O, T). Values are expressed as mean gray value ± SE. One-way ANOVA followed by the post hoc Scheffé test: ^∗∗∗p < 0.001. Scale bars in horizontal order indicate 500 μm (for the hippocampus), 200 μm (for the cortex), 50 μm (for the cortex), and 50 μm (for the white matter).