Overview
- The study, published May 26, 2026 in Aging Cell, reports that removing brain‑made estrogen in older female mice coincided with changes in hippocampal extracellular matrix (ECM) gene expression and measurable memory and behavior deficits.
- Researchers used genetically engineered mice lacking aromatase, the enzyme that makes estrogen, with whole‑body and brain‑specific deletions to compare young and old animals of both sexes and isolate female‑specific effects.
- The extracellular matrix is the network of molecules that fills space between brain cells and helps neurons communicate, and the study is the first to link estrogen loss directly to ECM disruption in the hippocampus.
- Authors propose the ECM as a new therapeutic target distinct from amyloid‑focused approaches and say the findings reopen questions about hormone replacement strategies, although clinical relevance is unproven and HRT trials have shown mixed results.
- Because nearly two‑thirds of Americans with Alzheimer's are women, the team calls for human studies to test whether preserving brain estrogen or restoring ECM structure can protect cognition in postmenopausal women.