Dietary magnesium deficiency impairs hippocampus-dependent memories without changes in the spine density and morphology of hippocampal neurons in mice.
Brain Res Bull. 2019 Jan ;144:149-157. Epub 2018 Nov 27. PMID: 30500564
Magnesium (Mg) is an essential mineral for maintaining biological functions. One major action of Mgin the brain is modulating the voltage-dependent blockade of N-methyl-d-aspartate type glutamate receptors, thereby controlling their opening, which is crucial for synaptic plasticity. Therefore, Mghas been shown to play critical roles in learning and memory, and synaptic plasticity. However, the effects of dietary Mgdeficiency (MgD) on learning and memory and the morphology of neurons contributing to memory performance have not been examined in depth. Here, we show that MgD impairs hippocampus-dependent memories in mice. Mice fed an MgD diet showed deficits in hippocampus-dependent contextual fear, spatial and social recognition memories, although they showed normal amygdala- and insular cortex-dependent conditioned taste aversion memory, locomotor activity, and emotional behaviors such as anxiety-related and social behaviors. However, MgD mice showed normal spine density and morphology of hippocampal neurons. These findings suggest that MgD impairs hippocampus-dependent memory without affecting the morphology of hippocampal neurons.