The Role of Astroglia in the Antidepressant Action of Deep Brain Stimulation

With more than 350 million depressed individuals worldwide, major depressive disorder is one of the most common psychiatric illnesses. Although, the pathophysiology of depression is far from being fully understood, five decades of development of different classes of antidepressants targeting central monoaminergic systems (serotonin, noradrenaline and dopamine) has led to the emergence of the monoaminergic hypothesis. However, despite a growing number of available pharmacotherapies, treatment of major depression nevertheless remains unsatisfactory. ROLE OF GLIA IN THE PHYSIOPATHOLOGY OF DEPRESSION AND THE MECHANISMS OF ACTION OF ANTIDEPRESSANTS Ten years ago it was postulated that abnormal functioning of glial cells, particularly of astrocytes, contribute to the physiopathology of depression (for review, Rajkowska andMiguel-Hidalgo, 2007). Structural and functional abnormalities of glial cells were found in brains of post-mortem depressed patients and in animal models of depression (Czéh et al., 2006, 2007; Banasr et al., 2007; Sun et al., 2012). Moreover, it has been shown that a loss or a functional alteration of astrocytes in th