Thyroid Hormone as a Sex-Specific Mediator of Drug Reward
Speaker: Dr. Deena Walker, Assistant Professor of Behavioral Neuroscience, School of Medicine, Oregon Health & Science University
Deena Walker is an assistant professor in the Department of Behavioral Neuroscience at Oregon Health & Science University. She is passionate about understanding how hormones influence the brain and behavior and is dedicated to using her diverse training background to identify precision-based treatments for neuropsychiatric disorders, particularly in women. Currently, her lab is focused on how hormones influence sex-specific vulnerability in substance/alcohol use disorder. She moved to Portland, Oregon in 2020 after doing her postdoctoral fellowship at Icahn School of Medicine at Mt. Sinai where she studied the molecular mechanisms of sex differences in addiction. As a PhD student at The University of Texas at Austin, she studied how the brain controls ovulation and menopause with a specific focus on hormonal regulation of gene expression. In recognition of her innovative and impactful science, she has been awarded several early career awards, including the Frank A. Beach Early Career Investigator Award from the Society for Behavioral Neuroendocrinology in 2023. In addition to her laboratory work, Dr. Walker is active in science outreach and storytelling. Her stories about the impact of her own life experiences on her scientific questions have been featured on the podcast StoryCollider.
Talk summary: The molecular mechanisms underlying sex differences in motivation and reward are likely hijacked by drugs of abuse and serve as candidates underlying well-established sex differences in substance use disorder (SUD). Why males and females become addicted to drugs of abuse at different rates is an elusive and unanswered question that involves several variables including genetics, social pressures, life experience, and hormone signaling. Most studies investigating sex differences in drug-associated behaviors and transcription have focused on sexually dimorphic neuroendocrine systems like the reproductive axis. However, our lab investigates the thyroid hormone system, a regulator of energy and metabolism, as a candidate for regulating sex-specific motivated behaviors. Canonically, thyroid hormones, when bound to their receptors, are transcription factors that mediate the transcriptional response to drugs of abuse. We will discuss our recent findings indicating that thyroid hormones are disrupted by drugs of abuse which are associated with transcriptional changes in the brain’s reward circuitry. We then build off of these data to show that central activation of thyroid hormone receptors, via treatment with a CNS-specific thyromimetic developed by our collaborators at OHSU, reduces reward-related behaviors, suggesting thyroid hormone signaling as a potential novel treatment for substance and alcohol use disorder. Together our data not only suggest that thyroid hormone is a critical regulator of the rewarding properties of drugs of abuse, but highlight ways in which sex-specific transcriptional responses to drugs of abuse can be leveraged to identify potential therapeutic targets for substance- and alcohol-use disorder.
Agenda:
12-12:45 pm EDT: Speaker presentation
12:45-1:00 pm EDT: Question and answer period
