title: [Role of the cytokine network in the CNS and psychiatric disorders].
abstract: There is a strong interrelationship between the immune system, the central nervous system and psychological processes that are suggested to play a pivotal role in the pathogenesis of psychiatric disorders. In schizophrenia and depression, activation of the immune system has been observed repeatedly. Cytokines play a key role in immune activation. They are actively transported into the CNS, but also released from activated glia cells. Cytokines activate glia cells in the CNS to produce other cytokines, and a cascade of cytokine effects may be initiated by this mechanisms. During the past few years, the influence of the cytokines on dopaminergic, noradrenergic and serotonergic neurotransmission and also on the hormones of the hypothalamus-pituitary-adrenal axis has been elucidated. It suggests a pivotal role in psychological processes and psychiatric disorders. For example, in schizophrenia the IL-2 cerebrospinal fluid concentration shows a stronger relationship to the relapse probability than catecholamine metabolites. Although the hypersecretion of IL-2 in schizophrenia and of IL-6 in depression are suggested to play key roles for these disorders, a specificity of certain cytokines for certain psychiatric disorders seems unlikely. Psychomotor, sleep and sickness behavior are influenced by IL-1, disturbances of memory and attention by IL-2, but also by TNF-alpha. From the distribution of cytokine receptors in the CNS conclusions can be drawn regarding the influence of cytokines on psychological processes. The finding that norepinephrine stimulates activated astrocytes to produce IL-6 implies that the cytokine cascade may be activated by neuronal processes under certain conditions. This can lead to a molecular biological explanation of the influences of stress on the immune system. Lastly, influences of the cytokines on blood-brain barrier disturbances and further consequences resulting from the role of the cytokine network in the CNS are discussed.
authors.affiliation: Psychiatrische Klinik, Ludwig-Maximilians-Universität, München.
authors.forename: N
authors.initials: N
authors.lastname: Müller
mesh_terms: D001812:Blood-Brain Barrier / Q000276:immunology; D001927:Brain Diseases / Q000175:diagnosis / Q000276:immunology* / Q000523:psychology; D016207:Cytokines / Q000502:physiology*; D003937:Diagnosis, Differential; D006801:Humans; D001523:Mental Disorders / Q000175:diagnosis / Q000276:immunology* / Q000523:psychology; D019965:Neurocognitive Disorders / Q000175:diagnosis / Q000276:immunology* / Q000523:psychology; D018377:Neurotransmitter Agents / Q000502:physiology; D011598:Psychoneuroimmunology
chemical_list: D016207:Cytokines; D018377:Neurotransmitter Agents