Neural mechanisms of social attachment disruption in frontotemporal dementia

PROJECT SUMMARY/ABSTRACT Social cognition, and social attachment in particular, is often significantly disrupted in age-related neuropsychiatric disease. Frontotemporal dementia (FTD) is characterized by disruptions in social attachment behavior and loss of empathy early in the course of the disease. We currently lack a mechanistic understanding of the neurobiology of attachment behavior or its disruption in disease and have no interventions for these profoundly impairing symptoms, despite their potential as early diagnostic and therapeutic targets. The candidate for this K08 Mentored Career Development Award is a physician scientist and psychiatrist at the University of California, San Francisco. Her long-term career goal is to understand the impact of aging and neurodegenerative disease on the neurobiology of social behavior. The overall objective of the proposed research plan is to elucidate the molecular and neural circuit pathways mediating social attachment changes in FTD. The candidate proposes to use the prairie vole, a unique model organism that forms long-term adult pair bonds, to understand the neurobiology of social attachment. In her preliminary work, she has used molecular genetic tools to knock out progranulin (Grn), one of the most common genetic causes of FTD, in the vole. This work represents an innovative and novel approach to studying attachment deficits in dementia. She proposes to first examine the effects of loss of genes relevant to social behavior and to FTD, the oxytocin receptor (OxtR) and Grn, using both behavioral and transcriptomic profiling with age. She will then test the hypothesis that loss of OxtR and Grn converge on specific neural circuits responsible for the presentation of social deficits, using in vivo calcium imaging and viral tracing methods to map patterns of neural activity and connectivity. The proposed research is significant because it seeks to mechanistically link the risk genes associated with neurodegenerative disease to the neural circuit changes and social attachment disruptions characteristic of these diseases. This proposal presents a five-year research career development program designed to provide a foundation for an independent research program. The specific career development goals outlined in this application include training in systems neuroscience, advanced sequencing and bioinformatics methods, and in translational neurodegenerative disease research. These skills build on the candidate's prior experience in neuroendocrine signaling and its role in aging biology and neurodegenerative disease. The primary mentorship team (Drs. Manoli, Miller, and Ingraham) has expertise in molecular genetics, systems neurophysiology, and translational FTD research. Other key contributors and collaborators provide expertise in vole behavior (Dr. Bales), transcriptomics and bioinformatics (Dr. Willsey), and comparative genomics (Dr. Yokoyama). The direct training in research methodology and career support will allow the candidate to transition to a career as an independent investigator in aging and brain health.