This proposal is for a K23 Mentored Patient-Oriented Research Career Development Award to complete training and research experience needed to prepare the candidate for a successful career as an independent investigator. The candidate's long-term goal is a career in academic child and adolescent psychiatry focused on research that improves the care of patients with depression. This will be accomplished through increased understanding of its pathophysiology. Depression is a significant and common illness during childhood, a major public health problem, and a leading causes of disability worldwide. Recent basic science and clinical research in adults with depression suggests that glutamate, the brain's primary excitatory neurotransmitter plays a role in the neurochemical basis of depression. There is little information about the functioning of glutamate in adolescents with depression. Proton magnetic resonance spectroscopy (1H-MRS) is a noninvasive brain imaging technique that measures the concentrations of brain chemicals such as glutamate. Intracortical facilitation (ICF) is a transcranial magnetic stimulation (TMS) neurophysiological test which measures the functioning of glutamate. The candidate proposes to use 1H-MRS and ICF in a cross-sectional study of glutamate concentrations and functioning in adolescent depression [with three groups] of subjects (depressed subjects who have not yet taken an antidepressant medication, subjects who had depression that responded to an antidepressant, and healthy controls). [Depressed subjects will have these two measures repeated after eight weeks of standard clinical treatment with fluoxetine. This will test the hypotheses that cortical glutamate concentrations are decreased while glutamate functioning is increased in adolescents with depression and that successful treatment with fluoxetine normalizes these differences.] This innovative approach will advance understanding of glutamate neurotransmission in adolescent depression, inform the development of new biomarkers, and assist with the identification of treatment targets. This project is tailored to inform subsequent longitudinal studies of depressed adolescents for federal R01 grant applications. The candidate has prior experience with ICF measures but would benefit from additional training in 1H-MRS methodology and TMS neurophysiology paradigms. The candidate and mentoring team propose a career development plan focused on 1H-MRS neuroimaging, TMS neurophysiology studies, clinical and translational research methodologies, [neurodevelopment,] and the neurobiology of disease research. This rigorous plan includes intensive mentoring, courses through the Mayo Clinic Graduate School, and international seminars. Well defined benchmarks regarding publications and grant submissions will ensure substantial productivity during the award period and a successful transition to an independent academic researcher in child and adolescent psychiatry.

Public Health Relevance

Adolescent depression has poorly understood biology and is a major public health problem. This project focuses on the use of two noninvasive measures of glutamate in the brain to study the biology of depression in adolescents with the goal of informing biomarker development and the identification of treatment targets. A comprehensive training plan will ensure substantial productivity during the award period and transition the candidate to a career as an independent clinician scientist.

National Institute of Health (NIH)
National Institute of Mental Health (NIMH)
Mentored Patient-Oriented Research Career Development Award (K23)
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Study Section
Child Psychopathology and Developmental Disabilities Study Section (CPDD)
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Sarampote, Christopher S
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Mayo Clinic, Rochester
United States
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Lee, Jonathan C; Lewis, Charles P; Daskalakis, Zafiris J et al. (2017) Transcranial Direct Current Stimulation: Considerations for Research in Adolescent Depression. Front Psychiatry 8:91
Croarkin, Paul E; Nakonezny, Paul A; Wall, Christopher A et al. (2016) Transcranial magnetic stimulation potentiates glutamatergic neurotransmission in depressed adolescents. Psychiatry Res 247:25-33
Mason, Brittany L; Brown, E Sherwood; Croarkin, Paul E (2016) Historical Underpinnings of Bipolar Disorder Diagnostic Criteria. Behav Sci (Basel) 6:
Lewis, Charles P; Port, John D; Frye, Mark A et al. (2016) An Exploratory Study of Spectroscopic Glutamatergic Correlates of Cortical Excitability in Depressed Adolescents. Front Neural Circuits 10:98
Croarkin, Paul E; Ameis, Stephanie H (2016) Editorial: Frontiers in Brain-Based Therapeutic Interventions and Biomarker Research in Child and Adolescent Psychiatry. Front Psychiatry 7:123
Cullen, Kathryn R; Jasberg, Suzanne; Nelson, Brent et al. (2016) Seizure Induced by Deep Transcranial Magnetic Stimulation in an Adolescent with Depression. J Child Adolesc Psychopharmacol 26:637-41
Croarkin, Paul E; Rotenberg, Alexander (2016) Pediatric Neuromodulation Comes of Age. J Child Adolesc Psychopharmacol 26:578-81
Wall, Christopher A; Croarkin, Paul E; Maroney-Smith, Mandie J et al. (2016) Magnetic Resonance Imaging-Guided, Open-Label, High-Frequency Repetitive Transcranial Magnetic Stimulation for Adolescents with Major Depressive Disorder. J Child Adolesc Psychopharmacol 26:582-9
Scola, Gustavo; McNamara, Robert K; Croarkin, Paul E et al. (2016) Lipid peroxidation biomarkers in adolescents with or at high-risk for bipolar disorder. J Affect Disord 192:176-83
Lewis, Charles P; Nakonezny, Paul A; Ameis, Stephanie H et al. (2016) Cortical inhibitory and excitatory correlates of depression severity in children and adolescents. J Affect Disord 190:566-575

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