Abstract
Glycogen synthase kinase-3 (GSK-3) (EC 2.7.1.37) is a protein kinase highly abundant in brain and involved in signal transduction cascades of multiple cellular processes, particularly neurodevelopment. Two forms of the enzyme, GSK-3α and -3β have been previously identified. We have previously reported reduced GSK-3β protein levels in postmortem frontal cortex of schizophrenic patients. In an attempt to explore whether reduction of GSK-3β levels is brain region specific we examined it in occipital cortex. In order to find out if the reduction in frontal cortex is reflected in altered activity we measured GSK-3 enzymatic activity in this brain region. Western-blot analysis of GSK-3β was carried out in postmortem occipital cortex of 15 schizophrenic, 15 bipolar, and 15 unipolar patients, and 15 normal controls. GSK-3 activity was measured by quantitating the phosphorylation of the specific substrate phospho-CREB in the frontal cortex specimens. GSK-3β levels in occipital cortex did not differ between the four diagnostic groups. GSK-3 activity in the frontal cortex of schizophrenic patients was 45% lower than that of normal controls (0.196±0.082 and 0.357±0.084 pmol/mg protein x min, respectively; Kruskal-Wallis analysis: chi-square=8.27, df=3, p=0.04). The other two diagnostic groups showed no difference from the control group. Our results are consistent with the notion that schizophrenia involves neurodevelopmental pathology.
Original language | English |
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Pages (from-to) | 101-105 |
Number of pages | 5 |
Journal | Schizophrenia Research |
Volume | 52 |
Issue number | 1-2 |
DOIs | |
State | Published - 1 Oct 2001 |
Keywords
- Enzyme activity
- Frontal cortex
- Glycogen synthase kinase-3
- Occipital cortex
- Postmortem brain
- Protein levels
ASJC Scopus subject areas
- Psychiatry and Mental health
- Biological Psychiatry