WSU researcher receives grant to study the neurobiology of depressed adolescent daughters of depressed mothers
January 30, 2009
DETROIT - Major depressive disorder affects 1 in 20 teenagers at any point in time, yet its neurobiology remains poorly understood. Frank MacMaster, Ph.D., a postdoctoral research assistant, was awarded nearly $60,000 for a Young Investigator Award from NARSAD, the world's largest donor-supported organization for mental health research, to investigate the neurobiology of familial depression - depression that has some degree of heredity - in adolescents. Working in the laboratory of David Rosenberg, M.D., in the Department of Psychiatry and Behavioral Neurosciences in the WSU's School of Medicine, MacMaster is focusing on depression in adolescent daughters of depressed mothers, a group at particularly high risk for the disorder, with the goal of finding biological markers indicative of the disease.
"There's no biological test currently for diagnosing psychiatric disorders. It's all up to the skill of the clinician to diagnose a patient based on the behaviors he or she displays," MacMaster said. "One of our big goals is to find enough biological markers to identify major depressive disorder and bi-polar disorder, eventually developing biological profiles for these diseases."
The study also has the potential to advance the development of more effective medications for adolescents, for whom current serotonin-based medications, such as Prozac, yield mixed results.
MacMaster is beginning his research by focusing on the activity of the frontal-limbic-hypothalamic-pituitary-adrenal (FL-HPA) axis, or what he refers to as the "stress axis." In stressful situations, the FL-HPA axis undergoes a sequence of reactions that result in the stress hormone cortisol being released into the body- in what is known as the "fight or flight" reaction - ending its trip by binding with receptors in the hippocampus. In people with depression, the cortisol releasers do not shut off when they should, and the feeling of stress persists.
One possible explanation for the defect could be there are fewer cortisol receptors in the hippocampus, a hypothesis based on a previous study that found smaller hippocampal volumes in children with familial depression. "What this study proposes to do is to look at things like hippocampal volume and cortisol concentrations, and try to link them together to get an understanding of what's going on with patients suffering from familial depression," MacMaster said.
MacMaster is beginning his research by focusing on depressed adolescent girls whose mothers also suffer from depression, due to the group's statistically high risk for the disorder - more women suffer from depression than men, at a rate of 2 to 1. Additionally, children's whose parents suffer from depression are two to three times more likely to become depressed themselves. Evidence from previous studies suggest a strong genetic component for depression in adolescent girls with depressed mothers. "One of the biggest obstacles for studying depression is that there are many things that can make you depressed," he said. "So for this project, we're using the most uniform group that's out there; depressed daughters of depressed mothers."
Though his current study is focused on the biological aspect of adolescent familial depression, MacMaster intends to incorporate environmental factors in future studies on the same group. "Environment and genetics are so intertwined in psychiatric disorders that you can't have one without the other," he said. "While environment can play a large role in and of itself, developing a biological profile for the disease is the vital first step from which we can advance our understanding of all the contributors of depression."
Wayne State University is one of the nation's pre-eminent public research universities in an urban setting, ranking in the top 50 in R & D expenditures of all public universities by the National Science Foundation. Through its multidisciplinary approach to research and education, and its ongoing collaboration with government, industry and other institutions, the university seeks to enhance economic growth and improve the quality of life in the city of Detroit, state of Michigan and throughout the world.