René Hen, Ph.D.Columbia University
René Hen was born in Strasbourg, France, and received his Ph.D. from University Louis Pasteur under the mentorship of Pierre Chambon. After a postdoctoral stay in Richard Axel’s laboratory at Columbia University, Hen became an assistant professor in Strasbourg. He then returned to Columbia University, where he is presently a professor of pharmacology and neuroscience and the director of the division of integrative neuroscience in the department of psychiatry. His laboratory is using animal models to elucidate the neural substrates that underlie mood and anxiety disorders.
René Hen has studied the contribution of serotonin (5-HT) receptors to pathological states such as depression and anxiety. Pharmacological studies and molecular cloning have identified several subtypes of receptors with distinct properties, signaling systems, and tissue distributions. However, the study of the function of individual serotonin receptor subtypes has been hampered by the lack of specific drugs. In addition, a number of the serotonergic drugs that are active in the treatment of neuropsychiatric disorders influence the whole serotonergic system. For example, antidepressants such as fluoxetine are 5-HT uptake blockers and potentiate the action of 5-HT at multiple post-synaptic sites. To dissect the contributions of individual serotonin receptors to physiology and behavior, mouse mutants lacking individual receptor subtypes were created in his laboratory, providing genetic models for a number of human behavioral traits such as impulsiveness, depression, and anxiety.
Tissue specific and conditional knockouts have been used to identify the neural circuits underlying these traits. Recently Hen’s lab has been investigating the function of the ventral hippocampus and the contribution of hippocampal neurogenesis to mood and cognition. Specifically, they have shown that antidepressants stimulate the division of neuronal progenitor cells in the dentate gyrus, which in turn results in an increase in the number of young neurons in the adult hippocampus. Furthermore, they have shown that hippocampal neurogenesis is required for some of the behavioral effects of antidepressants and for pattern separation. Novel therapies aimed at targeting directly hippocampal stem cells are currently under investigation for the treatment of mood disorders and age-related memory impairments.