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Updated: Jun 18, 2025

Assessment of Sexual Behavior of Male Mice
Published on: March 5, 2020
A second X chromosome improves cognition in aging male and female mice
Francesca Marino1,2, Dan Wang1, Gennifer E Merrihew3
1Department of Neurology and Weill Institute for Neurosciences, University of California, San Francisco, CA, USA.
Abstract:
Women show resilience to cognitive aging, in the absence of dementia, in many populations. To dissect sex differences, we utilized the FCG and XY* mouse models. Female gonads and sex chromosomes improved cognition in aging mice of both sexes. Further, presence of a second X in male and female mice conferred cognitive resilience while its absence in females blocked it. In the hippocampal proteome of aging female mice, the second X increased proteins involved in synaptogenesis signaling - a potential pathway to improved cognition.
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