Role of immunological factors in the pathophysiology and diagnosis of bipolar disorder: Comparison with schizophrenia

Abstract

Several lines of evidence point to the key role of neurobiological mechanisms and shared genetic background in schizophrenia and bipolar disorder. For both disorders, neurodevelopmental and neurodegenerative processes have been postulated to be relevant for the pathogenesis as well as dysregulation of immuno-inflammatory pathways. Inflammation is a complex biological response to harmful stimuli and it is mediated by cytokines cascades, cellular immune responses, oxidative factors and hormone regulation. Cytokines, in particular, are supposed to play a critical role in infectious and inflammatory processes, mediating the cross-talk between the brain and the immune system; they also possibly contribute to the development of the central nervous system. From this perspective, even though mixed results have been reported, it seems that both schizophrenia and bipolar disorder are associated with an imbalance in inflammatory cytokines; in fact, some of these could represent biological markers of illness and could be possible targets for pharmacological treatments. In light of these considerations, the purpose of the present paper was to provide a comprehensive and critical review of the existing literature about immunological abnormalities in bipolar disorder with particular attention to the similarities and differences with schizophrenia.

Multianalyte markers of schizophrenia and bipolar disorder: A preliminary study

“…Our finding is consistent with previous studies indicating similarities and differences in the immune system in individuals with schizophrenia and bipolar disorder based on genetic, neuropathological, and gene expression studies (Altamura et al, 2014;Mamdani et al, 2013). The further elucidation of the similarities and differences in the immune system activity of individuals with schizophrenia and bipolar disorder would represent a major step in terms of elucidating the role of immune alteration in the pathogenesis of these disorders.…”

Autistic and schizotypal traits and global functioning in bipolar I disorder

“…This complex condition is often exacerbated by the presence of one or more comorbid conditions, in addition to a number of clinical factors such long duration of illness (Altamura et al, 2015;Altamura et al, 2010). While BD, schizophrenia spectrum disorders (SSD) and autism spectrum disorders (ASD) are considered distinct conditions, there is evidence for an overlap between BD and SSD (Altamura, Buoli, & Pozzoli, 2014;Carroll & Owen, 2009;Moller, 2003), as well as between ASD and BD (Carroll & Owen, 2009;Stahlberg, Soderstrom, Rastam, & Gillberg, 2004). Indeed, BD has a number of genetic, symptomatological and epidemiological overlaps with SSD (Laursen, Agerbo, & Pedersen, 2009;Lichtenstein et al, 2009;Murray et al, 2004), and psychosis has been recognised as an important dimension in the psychopathology of BD (van Os & Kapur, 2009).…”

May Non-antipsychotic Drugs Improve Cognition of Schizophrenia Patients?

“…Some data indicate pro-inflammatory cytokines to be responsible for cognitive disturbances in schizophrenia [77]. In a doubleblind placebo-controlled study, 50 schizophrenia patients on risperidone (2-6 mg/day) treatment showed cognitive improvement by celecoxib add-on therapy, but without reaching statistical significance [78].…”