Stem cell therapy: a new approach to the treatment of refractory depression.

To better understand the relationship of repeated exposure to adversity during early development as a risk factor for refractory depression, we exposed pregnant female rats to ethanol and the resulting pups to corticosterone during adolescence. A stressful forced swim test was then used to induce depression-like behavior. The adolescent rat brains were examined for the possible therapeutic benefit of a combination of sertraline, an antidepressant, and neural stem cells (NSCs) complexed with atelocollagen in relation to the level of GABAergic interneuron and synaptic protein density in different brain regions. The combined exposures of prenatal and adolescent stress resulted in a reduction in parvalbumin (PV)-positive phenotype of GABAergic interneurons and reduced postsynaptic density protein 95 (PSD-95) levels in the anterior cingulate cortex, amygdala, and hippocampus. Treatments with sertraline and NSCs reversed the reductions in PV-positive cells and PSD-95 levels. Furthermore, the combined treatment of sertraline and NSCs resulted in reduced depressive-like behaviors. These experiments underscore a potentially important role for synaptic remodeling and GABAergic interneuron genesis in the treatment of refractory depression and highlight the therapeutic potential of stem cell and pharmacological combination treatments for refractory depression.