Inter-relationship of plasma markers of oxidative stress and thyroid hormones in schizophrenics

<p>Abstract</p> <p>Background</p> <p>The relationship of oxidative stress to thyroid hormones has not been studied in the schizophrenics. The present study determined the status and interrelationship of plasma markers of oxidative stress, nitric oxide and thyroid hormones in thirty (17 males and 13 females) newly diagnosed patients with acute schizophrenia before initiation of chemotherapy. Twenty five (13 males and 12 females) mentally healthy individuals served as controls. Patients and controls with history of hard drugs (including alcohol and cigarette), pre-diagnosis medications (e.g. antiparkinsonian/antipsychotic drugs), chronic infections, liver disease and diabetes mellitus were excluded from the study. Plasma levels of total antioxidant potential (TAP), total plasma peroxides (TPP), nitric oxide (NO), malondialdehyde (MDA), thyroxine (T4), tri-iodothyronine (T3) and thyroid stimulating hormone (TSH) were determined in all participants using spectrophotometric and enzyme linked immunosorbent assay (ELISA) methods respectively. Oxidative stress index (OSI) was calculated as the percent ratio of total plasma peroxides and total antioxidant potential.</p> <p>Findings</p> <p>Significantly higher plasma levels of MDA (p < 0.01), TPP (p < 0.01), OSI (p < 0.01), T3 (p < 0.01) and T4 (p < 0.05) were observed in schizophrenics when compared with the controls. The mean levels of TAP, NO and TSH were significantly lower in schizophrenics (p < 0.01) when compared with the controls. The result shows that T3 values correlate significantly with MDA (p < 0.05) and TPP (p < 0.01) in schizophrenics.</p> <p>Conclusions</p> <p>Higher level of TPP may enhance thyroid hormogenesis in schizophrenics. Adjuvant antioxidant therapy may be a novel approach in the treatment of schizophrenic patients.</p

Neuropathological Similarities and Differences between Schizophrenia and Bipolar Disorder: A Flow Cytometric Postmortem Brain Study

Recent studies suggest that schizophrenia (SCH) and bipolar disorder (BPD) may share a similar etiopathology. However, their precise neuropathological natures have rarely been characterized in a comprehensive and quantitative fashion. We have recently developed a rapid, quantitative cell-counting method for frozen unfixed postmortem brains using a flow cytometer. In the present study, we not only counted stained nuclei, but also measured their sizes in the gray matter of frontopolar cortices (FPCs) and inferior temporal cortices (ITCs) from patients with SCH or BPD, as well as in that from normal controls. In terms of NeuN(+) neuronal nuclei size, particularly in the reduced densities of small NeuN(+) nuclei, we found abnormal distributions present in the ITC gray matter of both patient groups. These same abnormalities were also found in the FPCs of SCH patients, whereas in the FPCs of BPD patients, a reduction in oligodendrocyte lineage (olig2(+)) cells was much more common. Surprisingly, in the SCH FPC, normal left-greater-than-right asymmetry in neural nuclei densities was almost completely reversed. In the BPD FPC, this asymmetry, though not obvious, differed significantly from that in the SCH FPC. These findings indicate that while similar neuropathological abnormalities are shared by patients with SCH or BPD, differences also exist, mainly in the FPC, which may at least partially explain the differences observed in many aspects in these disorders

Towards a solution for performance related confounds: frontal, striatal and parietal activation during a continuous spatiotemporal working memory manipulation task

Item does not contain fulltextWorking memory plays a role in various forms of psychopathology. However, working memory consists of multiple theoretical components that may be differently taxed by various specific types of task, and brain activation differences between patients and healthy controls may result from differences in task performance. This makes it difficult to interpret such results in terms of disease-related dysfunctions in affected regions or networks. The aim of the current study was to determine the brain activation related to the updating of spatiotemporal content of working memory, in such a way that performance-related confounds in future clinical studies would be minimized. Nineteen healthy volunteers performed a task involving a continuous updating process during fMRI measurement. A frontostriatal network including medial and lateral prefrontal cortex, inferior frontal cortex, premotor cortex, supplementary motor cortex, thalamus and putamen was found to be related to the updating process. The results constrain the set of brain regions plausibly related to the specific updating component of working memory. Further, the task design may be of use in future studies of pathological conditions such as schizophrenia due to the minimization of potential confounds