SEX DIFFERENCES IN MICROGLIA MORPHOLOGY IN RESPONSE TO ISCHEMIC STROKE

Abstract

In this study we assessed microglia morphology in male, pre-menopausal female, and post menopausal female mice (Male n = 5-6; Pre M n = 6; PM n = 8) following 8 hours of reperfusion, as a measurable response to injury. We hypothesized that because the size of infarct is decreased in pre-menopause female versus post-menopause female and male mice, that changes in microglia morphology post stroke will vary according to sex group. Using skeletal and fractal analysis, we found that ramified morphology is decreased in proximity to injury (endpoints/cell region main effect: F (3,68) = 20.71, p < 0.0001; process length/cell region main effect: F (3,68) = 11.63, p < 0.0001); however there are no differences among sex groups for the endpoints/cell variable (F (2,68) = 0.6, p < 0.55). In addition, fractal dimension decreased in proximity to the ischemic region with significant differences according to sex group (two-way ANOVA: region: F (3,57) = 36.80, p < 0.0001; sex group: F (2,19) = 7.5, p < 0.01). The focus of this study is on the basic discovery of microglia morphological response that can be used to develop treatments that have minimal variability among sex groups.