Wnt/²-catenin Signaling is Necessary for E2-Mediated Memory Enhancement
Mentor 1
Dr. Frick
Location
Union Wisconsin Room
Start Date
28-4-2017 1:30 PM
End Date
28-4-2017 4:00 PM
Description
Estrogens mediate the function and morphology of the hippocampus, a brain region important for learning and memory. In the dorsal hippocampus, the potent estrogen estradiol facilitates memory through the activation of cell-signaling cascades. The Wnt/β-catenin cell-signaling pathway regulates hippocampal development and synaptic plasticity. Our lab previously showed that blockade of Wnt/β-catenin signaling with Dickkopf-1 (Dkk-1) impairs object recognition memory in male mice (Fortress et al, 2013). However, the potential involvement of Wnt/β-catenin signaling in the memory-enhancing effects of E2 are unknown. To address this issue, 10 week-old ovariectomized female C57BL/6 mice were trained on object recognition (OR) and object placement (OP) tasks designed to test object recognition and spatial memory. Immediately after training, mice received bilateral infusions of vehicle or Dkk-1 into the dorsal hippocampus and unilateral infusion of vehicle or E2 in the dorsal third ventricle. Memory was tested 24 or 48 h later. In contrast to mice receiving infusions of E2+vehicle, those receiving infusions of E2+Dkk-1 did not exhibit intact memory consolidation in either task. These results indicate that Wnt/β-catenin signaling is necessary for the memory-enhancing effects of E2 in female mice. Future studies will characterize the effects of E2 on Wnt/β-catenin signaling in the dorsal hippocampus.
Wnt/²-catenin Signaling is Necessary for E2-Mediated Memory Enhancement
Union Wisconsin Room
Estrogens mediate the function and morphology of the hippocampus, a brain region important for learning and memory. In the dorsal hippocampus, the potent estrogen estradiol facilitates memory through the activation of cell-signaling cascades. The Wnt/β-catenin cell-signaling pathway regulates hippocampal development and synaptic plasticity. Our lab previously showed that blockade of Wnt/β-catenin signaling with Dickkopf-1 (Dkk-1) impairs object recognition memory in male mice (Fortress et al, 2013). However, the potential involvement of Wnt/β-catenin signaling in the memory-enhancing effects of E2 are unknown. To address this issue, 10 week-old ovariectomized female C57BL/6 mice were trained on object recognition (OR) and object placement (OP) tasks designed to test object recognition and spatial memory. Immediately after training, mice received bilateral infusions of vehicle or Dkk-1 into the dorsal hippocampus and unilateral infusion of vehicle or E2 in the dorsal third ventricle. Memory was tested 24 or 48 h later. In contrast to mice receiving infusions of E2+vehicle, those receiving infusions of E2+Dkk-1 did not exhibit intact memory consolidation in either task. These results indicate that Wnt/β-catenin signaling is necessary for the memory-enhancing effects of E2 in female mice. Future studies will characterize the effects of E2 on Wnt/β-catenin signaling in the dorsal hippocampus.
