Reversing Corticosteroid Induced Memory Impairment

Stress and corticosteroid exposure are associated with changes in both the human and animal hippocampus. An extensive literature suggests that corticosteroid-induced changes in the hippocampus are, in part, mediated through increases in extracellular glutamate. In animals, agents that decrease glutamate release prevent dendritic changes in the hippocampus secondary to stress or corticosterone. We have developed a research program using patients receiving prescription corticosteroids (e.g., prednisone) to explore the effects of corticosteroids on the human hippocampus. Our research program is translational in focus, with a goal of exploring whether the reported effects of corticosteroids on the animal hippocampus are also found in humans. A current focus of our research is examining glutamate release inhibitors in patients taking corticosteroids. We have both open-label and placebo-controlled pilot data suggesting that the glutamate release inhibitor lamotrigine is associated with significant improvement in declarative memory (a measure of hippocampal performance) in this population. A definitive study examining declarative memory in corticosteroid-dependent patients receiving lamotrigine vs. placebo is proposed. Neuroimaging and mood will also be assessed.