Sex, stroke and the aging brain: A neuroendocrine perspective

Ischemic stroke, due to prolonged loss of blood supply to the brain, can result in loss of critical brain function. Worldwide, stroke is the 3rd leading cause of death and among the principal causes of disability. Stroke risk increases with age, and increasingly, more women are at risk for stroke than men. This risk increases at the menopause, when ovarian function is reduced, and stroke risk, paradoxically increases in older women who use estrogen therapy at menopause. My lab is interested in understanding whether hormone therapy at menopause is beneficial or deleterious for the brain. Using an animal model to mimic the menopause and an experimental stroke model, our studies show that older “acyclic” female rats sustain more brain tissue damage than younger females. Additionally, estrogen treatment to older females exacerbates tissue damage resulting from ischemia; while estrogen treatment to younger females is neuroprotective. In order to solve this paradoxical effect of estrogen on the young and aging brain, this talk will focus on two active lines of research in my lab: the first approach focuses on the age-related decline of other peptide hormones which interact with estrogen and the second focuses on a class of small molecules called microRNA that have disproportionally large effects on the transcriptome