Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was carried out to examine some components of in vivo immune function in major depression and schizophrenia. Toward this end, plasma concentrations of interleukin-1 beta (IL-1 beta) and IL-6, soluble IL-2 receptor (sIL-2R), and transferrin receptor (TfR) were measured in 28 normal controls, 11 schizophrenics and 13 major-depressed patients. Schizophrenic and major-depressed patients showed significantly higher plasma sIL-2R and TfR than normal controls. There was a trend toward higher plasma IL-6 in the psychiatric patients, and particularly in schizophrenic patients, than in normal volunteers. In normal controls and in the total study group, there were highly significant and positive correlations between plasma TfR and sIL-2R concentrations. It is suggested that schizophrenia and major depression are characterized by immune disorders that may indicate activation of cell-mediated immunity such as T-cell activation.
 ...
PMID:Plasma-soluble interleukin-2 and transferrin receptor in schizophrenia and major depression. 777 17

The pathophysiology of psychotic and other symptoms in schizophrenia remains a mystery despite decades of research. Even though it has been suspected for many years that autoimmune mechanisms may play a role in the pathophysiology of schizophrenia, firm evidence for this hypothesis has been lacking. Our studies, over the last 10 years, have revealed that a subgroup of schizophrenics have several significant immunological abnormalities, including increased prevalence of autoimmune diseases and of antinuclear antibodies (ANA) and anticytoplasmic antibodies (ACA), decreased lymphocyte interleukin-2 (IL-2) production, increased serum IL-2 receptor concentration, increased serum IL-6 concentration, and an association with HLA antigens. These findings are characteristic of autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis and insulin-dependent diabetes mellitus. We also found that some schizophrenics have antibodies to hippocampal antigens (AHA) in their serum, together with lowered IL-2 production. None of the above findings can be interpreted as definitely confirming the role of autoimmunity in schizophrenia. Nevertheless, taken together, the recent evidence points towards the existence of a subgroup of schizophrenics who have immunological findings consistent with that hypothesis. Further studies directed at finding the brain antigens targeted by the immune system in these patients, and longitudinal studies correlating clinical and immune changes over time, are needed.
 ...
PMID:Autoimmunity in schizophrenia: a review of recent findings. 825 Nov 50

Some evidence points towards a possible autoimmune role in the aetiology of schizophrenia. Experimental findings provide contradictory results regarding abnormalities in cytokine production in this disorder. In the present study we tested the production of cytokines in CSF and serum in 16 schizophrenic patients and 10 healthy controls (tumor necrosis factor alpha - TNF alpha; interleukins IL-1 beta, IL-2, IL-6, soluble IL-2 receptor). Cytokine levels were evaluated by radioactively-labeled antibodies (IL-1 beta, IL-2, IL-6), by enzyme-linked immunoassay (TNF) and by a sandwich enzyme immunoassay (soluble IL-2 receptor). No significant differences were found in either CSF fluid or serum levels of TNF and IL-2 or IL-6. Interleukin-1 beta was significantly decreased in patients' CSF and serum as compared to controls. Soluble interleukin-2 receptor levels were decreased in CSF of patients, but highly increased in their serum in comparison with controls. Changes in various cytokine levels in CSF fluid and serum of schizophrenic patients probably reflect interrelated process of growth, degeneration or neuroimmunological abnormalities, which may all play a role in the pathophysiology of schizophrenia. The present study supports evidence for change in immune activation, probably of peripheral origin, in schizophrenic patients.
 ...
PMID:Changes in interleukin-1 beta and soluble interleukin-2 receptor levels in CSF and serum of schizophrenic patients. 856 79

Schizophrenia may result from immune or inflammatory disorders, which are mediated by cytokines. Data in this field are heterogeneous and often contradictory. We investigated circulating levels of IL-6 and TNF-alpha, two distinct proinflammatory cytokines. Using immunoassay, we assessed IL-6 and TNF-alpha in serum from chronic schizophrenic patients (n = 30) and normal controls (n = 15). Circulating levels of IL-6 were higher in patients than in controls; those of TNF-alpha were not significantly higher than in controls. In addition, IL-6 levels were higher in patients with acute exacerbation of schizophrenia than in patients with remissions. Our results suggest that immunologic abnormalities in schizophrenia may be related to a specific inflammatory process mediated by IL-6. An interesting line of research would be the evaluation of IL-6 cerebral production in CSF.
 ...
PMID:Elevated circulating levels of IL-6 in schizophrenia. 882 53

The paper is a review of the literature on cellular and humoral immunity in schizophrenic patients. The reports have revealed that there are manifestations of autoimmunological process in a subgroup of schizophrenics (among others: increased serum level of specific and non-specific autoantibodies, decreased lymphocyte interleukin-2 production, increased soluble IL-2 receptor concentration, increased serum IL-6 level, presence of lymphocyte abnormalities and association with HLA antigens. It is suggested that virus infection may provoke the appearance of autoimmunological reaction, while genetic factors might increase some predisposition to this reaction. The reports have also revealed that autoimmunity may play a role in pathogenesis of schizophrenia in a subgroup of schizophrenic patients who have immunological abnormalities.
 ...
PMID:[Changes of humoral and cellular immunity in schizophrenia]. 898 18

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.
 ...
PMID:[Role of the cytokine network in the CNS and psychiatric disorders]. 913 17

Pro-inflammatory cytokines are dysregulated in schizophrenia. To determine the nature of the so-called inflammatory syndrome in schizophrenia, we investigated the circulating levels of various cytokines (interleukin (IL)-1 beta, IL-6, tumor necrosis factor (TNF)alpha), their natural antagonist (IL1-ra, TNF-RI, TNF-RII) and leukocyte activation markers (the soluble receptor of interleukin-2, soluble CD14 and soluble CD23) in subjects with chronic schizophrenia (n = 18) and in normal controls (n = 21). The levels of IL-1 beta and its antagonist and the levels of leukocyte activation markers were not significantly differents between patients and controls. Circulating levels of TNF alpha were significantly (p < 0.05) higher in patients than in controls and did not result from variations of its antagonist levels. The significant (p < 0.05) increase in patient IL-6 was related specifically to clinical status, i.e. illness duration. These data suggest a specific cytokine-mediated syndrome in schizophrenia. We hypothesize that TNF alpha and IL-6 reflect the genetic background of disease suceptibility.
 ...
PMID:A differential role for interleukin-6 and tumor necrosis factor-alpha in schizophrenia? 932 55

1. Parallel to the current rapid development of new immunological methods, immune mechanisms are gaining more importance for our understanding of psychiatric disorders. The purpose of this article is to review basic and clinical investigations that elucidate the relationship between the CNS and the immune system. 2. The topical literature dealing with the interactions of immune system, neurotransmitters, psychological processes, and psychiatric disorders, especially in relation to cytokines, is reviewed. 3. An activation of the immune system in schizophrenia and depressive disorders has repeatedly been described. Cytokines, actively transported into the CNS, play a key role in this immune activation. It was recently observed that cytokines activate astrocytes and microglia cells, which in turn produce cytokines by a feedback mechanism. Moreover, they strongly influence the dopaminergic, noradrenergic, and serotonergic neurotransmission. 4. There are indications that the cascade of cytokines can be activated by neuronal processes. These findings close a theoretical gap between stress and its influence on immunity. Psychomotor, sickness behavior and sleep are related to IL-1; disturbances of memory and cognitive impairment are to IL-2, in part also to TNF-alpha. The hypersecretion of IL-2 is assumed to have a prominent influence on schizophrenia, and IL-6, on depressive disorders. 5. Although single cytokines most likely do not have a specificity for certain psychiatric disorders, a characteristic pattern of cytokine actions in the CNS, including influences of the cytokines on the blood-brain barrier, seems to play a role in psychiatric disorders. This may have therapeutic implications for the future.
 ...
PMID:Psychoneuroimmunology and the cytokine action in the CNS: implications for psychiatric disorders. 953 65

Interleukin (IL)-1, IL-2 and IL-6 influence central monoamine activity in a cytokine-specific manner. We demonstrated that whereas IL-2 increased hypothalamic and hippocampal norepinephrine (NE) utilization, and DA turnover in the prefrontal cortex, IL-6 induced profound elevations of serotonin (5-HT) and mesocortical dopamine (DA) activity in the hippocampus and prefrontal cortex [S. Zalcman, J.M. Green-Johnson, L. Murray, D.M. Nance, D.G. Dyck, H. Anisman, A. H. Greenberg, Cytokine-specific central monoamine alterations following IL-1, -2 and -6 administration, Brain Res. 643 (1994) 40-49]. IL-1, in contrast, induced a wide range of central monoamine alterations. We presently report that these cytokines also differentially influence behavior. Profound reductions in non-ambulatory and ambulatory exploration were induced in BALB/c mice following IL-1 administration. In contrast, IL-2-treated mice displayed significant increases in the time spent engaged in non-ambulatory exploration, digging, rearing (particularly the number of free rears), and in the investigation of a novel stimulus (i.e., increased number and duration of stimulus contacts). IL-6-treated mice, moreover, exhibited significant increases in the time spent engaged in ambulatory exploration, digging and rearing (particularly the number of free rears, which tended to be of short duration). Modest increases in locomotion and grooming were also observed in IL-6-treated animals. Plasma corticosterone levels did not vary significantly as a function of IL-6 treatment. Hence, cytokine-specific behavioral-activating effects were induced following administration of IL-2 and IL-6. We suggest that these effects have adaptive significance and relevance to sickness behavior; however, pathological outcomes (e.g., schizophrenia, anxious-like states, anxious depression, motor abnormalities) could develop should these cytokines be overproduced or dysregulated.
 ...
PMID:Interleukin-2 and -6 induce behavioral-activating effects in mice. 980 16

It has been hypothesized that the immune system plays a pathogenetic role in psychiatric disorders, in particular in major depression and schizophrenia. This hypothesis is supported by a number of reports on altered circulating levels and in vitro production of cytokines in these disorders. However, the respective evidence is not consistent. This may be in part due to an incomplete control for numerous confounding influences in earlier studies. We investigated the plasma levels of cytokines and soluble cytokine receptors in psychiatric patients (N = 361) upon hospital admission and compared the results to those obtained in healthy controls (N = 64). By multiple regression analysis we found that circulating levels of interleukin-1 receptor antagonist (IL-1Ra), soluble IL-2 receptor (sIL-2R), tumor necrosis factor-alpha (TNF-alpha), soluble TNF receptors (sTNF-R p55, sTNF-R p75) and IL-6 were significantly affected by age, the body mass index (BMI), gender, smoking habits, ongoing or recent infectious diseases, or prior medication. Cytokine or cytokine receptor levels were significantly increased in patients treated with clozapine (sIL-2R, sTNF-R p75), lithium (TNF-alpha, sTNF-R p75, IL-6) or benzodiazepines (TNF-alpha, sTNF-R p75). Taking all these confounding factors into account, we found no evidence for disease-related alterations in the levels of IL-1Ra, sIL-2R, sTNF-R p75 and IL-6, whereas levels of TNF-alpha and sTNF-R p55 in major depression and sTNF-R p55 in schizophrenia were slightly decreased compared to healthy controls. We conclude that, if confounding factors are carefully taken into account, plasma levels of the above mentioned cytokines and cytokine receptors yield little, if any, evidence for immunopathology in schizophrenia or major depression.
 ...
PMID:Plasma levels of cytokines and soluble cytokine receptors in psychiatric patients upon hospital admission: effects of confounding factors and diagnosis. 1050 9


1 2 3 4 5 6 7 8 9 10 Next >>