Cytokines and psychopathology:: Lessons from interferon-α

Inteiferon-alpha is a potent inducer of the cytokine network and is notorious jbr causing behavioral alterations. Studies on inteiferon-alpha-treated patients reveal at least two distinct syndromes: 1) a mood/cognitive syndrome that appears late during interferon-alpha therapy is responsive to antidepressants and is associated with activation of neuroendocrine pathways and altered serotonin metabolism,: and 2) a neurovegetative syndrome characterized by pychomotor slowing, and fatigue that appears early during inteiferon-alpha treatment is antidepressant nonresponsive and may be mediated by alterations in basal ganglia dopamine metabolism. Findings from inteferon-alpha may provide important clues regarding, the pathophysiology and treatment of cytokine-induced behavioral changes in medically ill patients, while also potentially modeling the development of neuropsychiatric symptoms in patients without medical disordcrs.