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Hongjun Song

On using stem cells in the brain to study mental disorders:

Video transcription: "My lab works on stem cells in the nervous system. In particular, we look at how stem cells are regulated in the adult brain in the region called the hippocampus. This is a region involved in learning and memory and mood regulation. So we try to understand how actually these stem cells are activated and how they are regulated, or how they are dysregulated in mental disorders. We’re very interested in adult neural stem cells for a couple of reasons. One of them is it is generally believed that the adult brain is a very inhibitory environment for mature neurons. That is why during an injury, old neurons cannot regrow. However, these young neurons actually have an amazing capacity to regrow, reconnect and contribute to the circuitry. We want to know how actually they do that, how the young cells can connect to the circuitry and contribute to the brain functions. We also want to know how the local environment, in this particular case, actually can support that growth. How they can take upon those new neurons and make them useful. We hope is that by learning how they do it, we can use this strategy to promote regeneration of the mature brain in the other part where we do not have stem cells and to promote regeneration of mature neurons after injury.

"It turns out that these stem cells are very good tools to study why genes involved in mental disorder lead to defects in neurodevelopment. We’re also using this as a model system in rodents to study how a gene implicated in mental disorders, such as depression and schizophrenia, how do they affect the development of new neurons in the adult brain. At the same time, once we identify a specific defect caused by some genes involved in neurodevelopment, we actually can go back to human genetics to try to understand whether these are new genes involved in schizophrenia or depression or bipolar disorders."