Antidepressant-like effects of Deep Brain Stimulation in rats and the hypothalamic, pituitary, adrenal axis

Summary: 

Deep brain stimulation involves the implantation of electrodes into the brain through which current is delivered to specific targets. In patients with depression, promising results have been reported with DBS at different sites, including the subgenual cingulate gyrus (SCG). To investigate mechanisms of this therapy, we have recently studied the effects of DBS in the rodent homologue of the SCG, the ventromedial prefrontal cortex (vmPFC).

In a recent collaborative study between the University of Toronto/Centre for Addiction and Mental Health and the Universidade Federal de São Paulo, we have recently shown an important antianhedonic/antidepressant-like effect of vmPFC DBS in rats undergoing chronic unpredictable mild stress (CUS).

In this proposal we will test the hypotheses that 1) DBS will improve a series of tests to measure depressive- and anxiety-like behavioral in animals undergoing CUS and 2) DBS will reverse stress-induced changes in the hypothalamic-pituitary adrenal (HPA) axis. Patients with depression have high levels of corticosterone. Chronic stress and hypercortisolemia are often deleterious from a health perspective. Results from the experiments in this proposal may pave the way for future investigation to assess whether DBS may improve the consequences of hypercortisolemia and stress.

Summary personal information:

Dr. Luciene Covolan got her Ph.D. in Experimental Neurology and Neurophysiology at the Federal University of São Paulo, Brazil, in 1999. In 2000-2001 she did her post-Doctoral training at University of Oslo, Norway. She is Professor at University Federal of São Paulo, since 2006 and currently is chief of the Neurophysiology chair. Her main field of research is on basic mechanisms underlying temporal lobe epilepsy.

Dr. Hamani did his medical training and earned his Ph.D. in Experimental Neurology and Neurophysiology at the Federal University of São Paulo, Brazil. He completed his Neurosurgical Residency in 2002 at the University of São Paulo, followed by a fellowship in Functional Neurosurgery at the Toronto Western Hospital. Dr. Hamani is currently an Assistant Professor of Neurosurgery at the University of Toronto. His main research interests are in the field of the neurosurgical treatment of movement disorders, epilepsy, pain and psychiatric disorders.