Olive Leaf Polyphenols Attenuate the Clinical Course of Experimental Autoimmune Encephalomyelitis and Provide Neuroprotection by Reducing Oxidative Stress, Regulating Microglia and SIRT1, and Preserving Myelin Integrity

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 () of representative cortex photomicrographs (C, G, K, O, T). Values are expressed as . One-way ANOVA followed by the post hoc Scheffé test: . 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).

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