Psychiatric Times.
No. 7
New Research
Inflammation, Psychosis, and the Brain
By Tatiana Falcone, MD, Erin Carlton, MS, Kathleen Franco, MD, and Damir Janigro, PhD |
July 10, 2009
Dr Falcone is associate professor of psychiatry in the department of psychiatry and neurology at the Cleveland Clinic Neurological Institute. Erin Carlton is a medical student at the University of Toledo. Dr Franco is a consultation liaison psychiatrist at the Cleveland Clinic and associate dean of admissions and student affairs, and professor of medicine and psychiatry at the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University.
Dr Janigro is the director of cerebrovascular research at Cleveland Clinic and professor of molecular medicine at the Cleve-land Clinic Lerner College of Medicine.
Drs Falcone and Franco and Ms Carlton report no conflicts of interest concerning the subject matter of this article. Dr Janigro reports that he has a US patent on S100ß.
When comparing hematological results of these patients with those of controls, monocytosis was the most common and statistically significant finding (P < .01) (Figure 2).
In the psychotic group, most patients had monocyte counts that were well above what is considered normal for children. The percentage of monocytes was particularly high. These findings did not correlate with drug use before admission or with therapeutic and pharmacological interventions.
Prospective study of inflammatory markers in children with psychosis
To further assess the role of inflammation in the pathogenesis of psychosis, we studied the relationship between S100b serum concentrations and acute psychosis in children and adolescents. Participants had been admitted to the child and adolescent inpatient psychiatry unit with a diagnosis of acute psychosis. (Psychosis NOS, schizophreniform disorder, or schizophrenia had been diagnosed in the past 6 months.) Parent(s) or guardian(s) gave consent for us to obtain blood samples.
Our hypothesis was that proinflammatory changes were responsible for observed differences in the monocyte counts of the psychotic patients and that a downstream effect of monocytosis was damaging to the endothelial cells constituting the BBB. Serum samples of 10 psychotic children were compared with those of 9 healthy children. In the healthy control group, a preliminary interview had ruled out psychosis, any neurodegenerative disorder, fever, current infection, or current use of antibiotics.
S100b levels were significantly higher in children with psychosis than in controls (P < .05) (Figure 3). Most psychotic children had S100b levels above normal. Nonetheless, S100b is a nonspecific measure of BBB permeability. Elevated S100b does not give insight into the mechanism of BBB disruption, and it does not prove a causal link to psychotic symptoms. Psychosis may precede elevations of S100b and BBB dysfunction. From this standpoint, S100b can still serve as a biomarker of BBB disruption.
Future research may determine whether serum factors are causally related or only associated with transendothelial leakage of S100b.
Conclusion
First-episode psychosis in children is associated with evidence of increased inflammation (eg, monocytosis) and elevated serum concentrations of S100b. Several cytokines—TNF-a, IL-1b, and IL-6, among others—have been reported to be elevated in patients with schizophrenia. These inflammatory mediators are often associated with BBB leakage, which is consis-tent with animal models of schizophrenia.21-24 Curiously, some antipsychotic medications have immunomodulatory effects.25
Our results support the inflammatory theory of schizophrenia that was formulated over a 100 years ago and perhaps offer hope that prevention of chronicity can occur if the first episode of psychosis is rapidly and effectively controlled.26 Although there are mixed results in 6 studies using anti-inflammatory medications in schizophrenic patients, Müller and colleagues27,28 believe that these agents are more likely to be effective in first-episode patients than in those with chronic schizophrenia.
Drug Mentioned in This Article
Lithium (Eskalith, Lithane, Lithobid)
1. Hanson DR, Gottesman II. Theories of schizophrenia: a genetic-inflammatory-vascular synthesis. BMC Med Genet. 2005;6:7.
2. Rothermundt M, Arolt V. Schizophrenia and immunity. In: Adler R, ed. Psychoneuroimmunology. Burlington, MA: Elsevier Academic Press; 2007:563-577.
3. Rothermundt M, Ponath G, Glaser T, et al. S100b serum levels and long-term improvement of negative symptoms in patients with schizophrenia. Neuropsychopharmacology. 2004;29:1004-1011.
4. Bayer TA, Wiestler OD, Wolf HK. Hippocampal loss of N-methyl-d-aspartate receptor subunit 1 mRNA in chronic temporal lobe epilepsy. Acta Neuropathol. 1995;89:446-450.
5. Radewicz K, Garey LJ, Gentleman SM, Reynolds R. Increase in HLA-DR immunoreactive microglia in frontal and temporal cortex of chronic schizophrenics. J Neuropathol Exp Neurol. 2000;59:137-150.
6. Hirsch S. Glial cell changes measured by PK11195 PET in patients with psychosis. Schizophr Res. 2004;
67(suppl 1):103.
7. Oby E, Janigro D. The blood-brain barrier and epilepsy. Epilepsia. 2006;47:1761-1774.
8. Silverman AJ, Sutherland AK, Wilhelm M, Silver R. Mast cells migrate from blood to brain. J Neurosci. 2000;20:401-408.
9. Fellerhoff B, Laumbacher B, Mueller N, et al. Associations between Chlamydophila infections, schizophrenia and risk of HLA-A10. Mol Psychiatry. 2007; 12:264-272.
10. de Boer AG, Breimer DD. Cytokines and blood-brain barrier permeability. Prog Brain Res. 1998;115: 425-451.
11. Schilling L, Wahl M. Mediators of cerebral edema. Adv Exp Med Biol. 1999;474:123-141.
12. Rivest S. What is the cellular source of prostaglandins in the brain in response to systemic inflammation? Facts and controversies. Mol Psychiatry. 1999;4:500-507.
13. Laflamme N, Lacroix S, Rivest S. An essential role of interleukin-1beta in mediating NF-kappaB activity and COX-2 transcription in cells of the blood-brain barrier in response to a systemic and localized inflammation but not during endotoxemia. J Neurosci. 1999;19:10923-10930.
14. Freyer D, Manz R, Ziegenhorn A, et al. Cerebral endothelial cells release TNF-alpha after stimulation with cell walls of Streptococcus pneumoniae and regulate inducible nitric oxide synthase and ICAM-1 expression via autocrine loops. J Immunol. 1999;163: 4308-4314.
15. Bruce LC, Peebles AM. Clinical and experimental observations on catatonia. J Mental Sci. 1903;49:
614-628.
16. Zorrilla EP, Cannon TD, Gur RE, Kessler J. Leukocytes and organ-nonspecifi autoantibodies in schizo-phrenics and their siblings: markers of vulnerability or disease? Biol Psychiatry. 1996;40:825-833.
17. Nikkila HV, Muller K, Ahokas A, et al. Accumulation of macrophages in the CSF of schizophrenic patients during acute psychotic episodes. Am J Psychiatry 1999;156:1725-1729.
18. Wilke I, Arolt V, Rothermundt M, et al. Investigations of cytokine production in whole blood cultures of paranoid and residual schizophrenic patients. Eur Arch Psychiatry Clin Neurosci. 1996;246:279-284.
19. Kowalski J, Blada P, Kucia K, et al. Neuroleptics normalize increased release of interleukin-1 beta and tumor necrosis factor-alpha from monocytes in schizophrenia. Schizophr Res. 2001;50:169-175.
20. Fan X, Pristach C, Liu EY, et al. Elevated serum levels of C-reactive protein are associated with more severe psychopathology in a subgroup of patients with schizophrenia. Psychiatry Res. 2007;149:267-271.
21. Van Eldik LJ, Wainwright MS. The Janus face of glial-derived S100b: beneficial and detrimental functions in the brain. Restor Neurol Neurosci. 2003;21: 97-108.
22. Jönsson H, Johnsson P, Höglund P, et al. Elimination of S100b and renal function after cardiac surgery. J Cardiothorac Vasc Anesth. 2000;14:698-701.
23. Nygaard O, Langbakk B, Romner B. Age- and sex-related changes of S-100 protein concentrations in cerebrospinal fluid and serum in patients with no
previous history of neurological disorder. Clin Chem. 1997;43:541-543.
24. Missler U, Wiesmann M, Ehlermann P, et al. Validation and comparison of two solid-phase immunoassays for the quantification of S-100b in human blood. Clin Chem. 2000;46:993-996.
25. Rothermundt M, Arolt V, Wiesmann M, et al.
S-100b is increased in melancholic but not in non-melancholic major depression. J Affect Disord. 2001; 66:89-93.
26. Janigro D. Blood-brain barrier, ion homeostasis and epilepsy: possible implications towards the understanding of ketogenic diet mechanisms. Epilepsy Res. 1999;37:223-232.
27. Müller N, Riedel M, Schwarz MJ, Engel RR. Clinical effects of COX-2 inhibitors on cognition in schizophrenia. Eur Arch Psychiatry Clin Neurosci. 2005;255:
149-151.
28. Müller N, Riedel M, Scheppach C, et al. Beneficial antipsychotic effects of celecoxib add-on therapy compared to risperidone alone in schizophrenia. Am J Psychiatry. 2002;159:6.
29. Rothermundt M, Ponath G, Arolt V. S100b in schizophrenic psychosis. Int Rev Neurobiol. 2004;59: 445-470.
30. Lara DR, Gama CS, Belmonte-de-Abreu P, et al. Increased serum S100b protein in schizophrenia: a study in medication-free patients. J Psychiatr Res. 2001;35:11-14.
31. Rothermundt M, Missler U, Arolt V, et al. Increased S100b blood levels in unmedicated and treated schizophrenic patients are correlated with negative symptomatology. Mol Psychiatry. 2001;6:445-449.
32. Rothermundt M, Ohrmann P, Abel S, et al. Glial cell activation in a subgroup of patients with schizophrenia indicated by increased S100b serum concentrations and elevated myo-inositol. Prog Neuropsychopharmacol Biol Psychiatry. 2007;31:361-364.
33. Jankovic BD, Djordjijevic D. Differential appearance of autoantibodies to human brain S100 protein, neuron specific enolase and myelin basic protein in psychiatric patients. Int J