Psychiatric disorders affect a large portion of the population and can be a huge burden for individuals and their families. Nearly all people suffering from psychiatric disorders have significant disruptions in circadian rhythms and the sleep/wake cycle. In fact, disrupted sleep patterns are one of the major diagnostic criteria for these disorders listed in the DSM V. There are several human genetic studies that have identified specific polymorphisms in circadian genes that associate with a range of psychiatric conditions. Furthermore, environmental disruptions to circadian rhythms including shift work, travel across time zones, and irregular social schedules can precipitate or exacerbate mood-related episodes, or put individuals at risk for substance abuse. Recent studies have found that molecular clocks are located throughout the brain and body where they participate in the regulation of most physiological processes, including those thought to be involved in mood and reward regulation. My lecture will summarize recent clinical and basic research findings from our group and others which implicate the circadian system as an important regulator of monoaminergic systems which are thought to play a role in the development of psychiatric disorders. I will also discuss the role of the suprachiasmatic nucleus (SCN) and the development of novel treatments that target the circadian system.
Dr. McClung’s work focuses on the molecular biology of mood disorders and drug addiction. This is a field that she have been involved in for many years. For her Ph.D. thesis at the University of Virginia with Dr. Jay Hirsh, she pioneered the use of the fruit fly, Drosophila as a model system to study the genes involved in cocaine sensitization. She went on to do her postdoctoral work with Dr. Eric Nestler at the University of Texas Southwestern Medical Center, who has been a leader in molecular psychiatry. There she studied the importance of changes in gene expression in the regulation of drug reward and mood-related behavior in pre-clinical models. Through work as both a graduate student and a postdoc, Dr. McClung became interested in the role of the genes that control circadian rhythms and central rhythm disruptions in the development of addiction and mood disorders. In 2005 she became an assistant Professor in Psychiatry at UT Southwestern, and in 2011 became an Associate Professor at the University of Pittsburgh School of Medicine in the Department of Psychiatry. Her work has been very fruitful: She has been awarded grants from NINDS, NIMH and NIDA for this work to continue, and has published several high profile papers. She has also received a Brain Disorders Award from the McKnight Foundation, the President’s Research Council Distinguished Young Investigator Award at UT Southwestern, and two NARSAD Young Investigator Awards. Dr. McClung and her team are committed to understanding the molecular mechanisms that underlie diseases like bipolar disorder, drug addiction and major depression with the hopes of developing better treatments in the future.