Mind the Gap: Estrogen receptor beta (ERβ) in astrocytes is a therapeutic target to prevent cognitive problems at menopause.

Abstract Aging is a risk factor for cognitive decline and susceptibility to neurodegenerative diseases. Some aspects of aging, like the loss of sex hormones, may be preventable. Menopause is associated with cognitive deficits and brain atrophy. Since standard hormone replacement therapy (HRT) does not mitigate these brain aging outcomes, a gap in knowledge involves understanding brain region-specific, cell-specific, and receptor-specific mechanisms underlying this neurodegeneration. Here, cognitive testing and in vivo magnetic resonance imaging demonstrated that ovarian hormones in female mice at midlife protect against hippocampal-dependent cognitive impairment and dorsal hippocampal atrophy. Further, this neuroprotection in females at midlife is lost in mice with selective deletion of estrogen receptor beta (ERβ) in astrocytes, but not neurons. This preclinical evidence identifies ERβ in astrocytes as a novel therapeutic target to prevent hippocampal-dependent cognitive deficits and reduce posterior hippocampus atrophy in menopausal women, a major unmet need in half the population.