Abnormalities in oligodendrocyte clusters inthe inferior parietal cortex in schizophreniaare associated with insight

ABSTRACT

Background and Objectives: Deficits in oligodendrocytes have been consistentlyreported in the brains of patients with schizophrenia and include alterations in theclustering pattern of oligodendrocytes. Recently it has been shown that oligodendrocyteprogenitors proliferate in the adult mammalian brain to form oligodendrocyte clusters(OlC). We previously found a deficit of oligodendrocytes in layer 3 of the inferior parietallobule (IPL) in subjects with schizophrenia with poor insight into disorder. We hypothesizedthat the number of OlC might be reduced in schizophrenia subjects with poor insight.Methods: Nissl-stained sections from the Stanley “Parietal Collection” from maleschizophrenia subjects (n = 24) that have poor, fair, or good insight into their disorder andnormal matched controls (n = 24) were studied. The numerical density (Nv) of OlC wasestimated in layer 3 of BA 39 and BA 40 by optical disector method.Results: The Nv of OlC was 23% lower in BA 39 and 30% lower in BA40 in the schizophreniagroup compared to the control group (p<0.01). Normal hemispheric differences inthe Nv of OlC in BA 39 were absent in the schizophrenia group. The Nv of OlC was significantlydecreased in BA39 in the subgroup with poor insight and in BA40 in the subgroupswith fair and good insight as compared to controls. In BA40 lower Nv of OlC (-40%,p<0.01) was found in the subgroup with adolescent onset of disease as compared to controls.Conclusions: The deficit of OlC may be associated with altered proliferation and/ormaturation of oligodendrocyte progenitors in schizophrenia (AU)