Choroid Plexus Enlargement and Allostatic Load in Schizophrenia.

Although schizophrenia is a brain disorder, increasing evidence suggests that there may be body-wide involvement in this illness. However, direct evidence of brain structures involved in the presumed peripheral-central interaction in schizophrenia is still unclear. Seventy-nine previously treatment-naïve first-episode schizophrenia patients who were within 2-week antipsychotics initial stabilization, and 41 age- and sex-matched healthy controls were enrolled in the study. Group differences in subcortical brain regional structures measured by MRI and the subclinical cardiovascular, metabolic, immune, and neuroendocrine biomarkers as indexed by allostatic load, and their associations were explored. Compared with controls, patients with schizophrenia had significantly higher allostatic load (P = .001). Lateral ventricle (P < .001), choroid plexus (P < .001), and thalamus volumes (P < .001) were significantly larger, whereas amygdala volume (P = .001) was significantly smaller in patients. The choroid plexus alone was significantly correlated with higher allostatic load after age, sex, education level, and the total intracranial volume were taken into account (t = 3.60, P < .001). Allostatic load was also significantly correlated with PANSS positive (r = 0.28, P = .016) and negative (r = -0.31, P = .008) symptoms, but in opposite directions. The peripheral multisystemic and central nervous system abnormalities in schizophrenia may interact through the choroid plexus during the early stage of the illness. The choroid plexus might provide a sensitive structural biomarker to study the treatment and prevention of brain-periphery interaction abnormalities in schizophrenia.

Ginkgo biloba and vitamin E ameliorate haloperidol-induced vacuous chewingmovement and brain-derived neurotrophic factor expression in a rat tardive dyskinesia model.

Neurodegeneration may be involved in the development of tardive dyskinesia (TD), and low levels of brain-derived neurotrophic factor (BDNF) may play a role. Ginkgo biloba (EGb761), a potent antioxidant, may have neuroprotective effects. We hypothesized that there would be decreased BDNF expression in TD, but that treatment with EGb761 would increase BDNF expression and reduce TD manifestations in a rat model. Forty rats were treated with haloperidol (2mg/kg/day via intraperitoneal injections) for 5weeks. EGb761 (50mg/kg/day) and vitamin E (20mg/kg/day) were then administered by oral gavage for another 5weeks, and we compared the effects of treatment with EGb761 or vitamin E on haloperidol-induced vacuous chewing movements (VCMs) and BDNF expression in four brain regions: prefrontal cortex (PFC), striatum (ST), substantia nigra (SNR), and globus pallidus (GP). Our results showed that haloperidol administration led to a progressive increase in VCMs, but both EGb761 and vitamin E significantly decreased VCMs. Haloperidol also decreased BDNF expression in all four brain regions, but both EGb761 and vitamin E administration significantly increased BDNF expression. Our results showed that both EGb761 and VE treatments exerted similar positive effects in a rat model of TD and increased BDNF expression levels in the four tested brain regions, suggesting that both EGb761 and vitamin E improve TD symptoms, possibly by enhancing BDNF in the brain and/or via their free radical-scavenging actions.

Beneficial effects of EGb761 and vitamin E on haloperidol-induced vacuous chewing movements in rats: Possible involvement of S100B mechanisms.

Tardive dyskinesia (TD) is a serious side effect induced by the long-term administration of typical antipsychotics. The pathophysiology of TD remains unclear, but experimental evidence suggests that neurodegeneration caused by free radicals may play an important role in TD development. S100B is considered a potential biomarker of structural neural and glial damage. This study investigated S100B expression in TD-related brain regions and assessed the effect of antioxidants Gingko biloba leaf extract (EGb761) and vitamin E (VE) on S100B in TD rats. A total of 32 rats were randomly divided into 4 study groups: saline control (saline), haloperidol alone group (Hal), EGb761-haloperidol (EGb-Hal), and vitamin E-haloperidol (VE-Hal). Rats were treated with haloperidol intraperitoneal injections (2mg/kg/day) each day for 5 weeks. EGb761 (50mg/kg/day) and VE (20mg/kg/day) were then administered during a 5-week withdrawal period. We performed behavioral assessments and immunohistochemically analyzed S100B expression in four TD-related brain regions. Our findings demonstrated that haloperidol administration led to a progressive increase in VCMs and in S100B expression in all four brain regions. Both EGb761 and VE reversed these changes, and there were no group differences between the EGb761 and VE groups. Our results indicated that long-term administration of haloperidol may induce VCMs and increase S100B expression in TD-related brain regions, and S100B may be a significant biomarker related to TD pathophysiology. Moreover, the antioxidant capacity of EGb761 and VE coupled with the possible neuroprotective effects of S100B may account for their success in improving the symptoms of haloperidol-induced TD.

Extract of Ginkgo biloba is equivalent to vitamin E in attenuating and preventing vacuous chewing movements in a rat model of tardive dyskinesia.

Free radical-mediated abnormalities may contribute toward the pathogenesis of tardive dyskinesia (TD). Many studies have reported the protective antioxidant and free radical-scavenging activities of extract of Ginkgo biloba (EGb761) against free radical-induced cell damage and dysfunction. This study aimed to compare the efficacy of EGb761 with that of vitamin E for the prevention and treatment of TD in a rat model. We carried out two studies. First, rats were injected with haloperidol (2 mg/kg intraperitoneally) daily for 5 weeks. EGb761 (50 mg/kg/day) or vitamin E (20 mg/kg/day) were then administered for another 5 weeks, and their effects on vacuous chewing movements (VCMs) were compared. Second, we compared 10 weeks of haloperidol alone with 10 weeks of haloperidol plus EGb761 or vitamin E. The administration of haloperidol led to a progressive increase in VCMs, which peaked at week 5. In study one, EGb761 and vitamin E, administered by an oral gavage for 5 weeks during withdrawal from chronic haloperidol treatment, decreased VCMs significantly, showing 83.8 and 91.0% reduction, respectively, compared with the haloperidol-alone group. In study two, the concomitant administration of EGb761 and vitamin E led to significantly fewer VCMs, by 64.4 and 73.9%, respectively, compared with the haloperidol-alone group. There was no significant difference in either study between EGb761 and vitamin E treatment. EGb761 shows promise for the prevention and treatment of TD in a rat model with a magnitude that was similar to that of vitamin E.