The impact of antipsychotic drugs on food intake and body weight and on leptin levels in blood and hypothalamic ob-r leptin receptor expression in wistar rats

OBJECTIVES: The aim of our study was to investigate the impact of typical and atypical antipsychotic drugs on leptin concentration in blood and changes in the receptor expression in the hypothalamus of male Wistar rats. METHODS: From the age of 13 to 18 weeks, three groups of 20 animals were fed an average dose of 3.5 + 0.03 mg/ kg body weight (BW) haloperidol; 30.6 + 0.22 mg/kg BW clozapine; or 14.9 + 0.13 mg/kg BW ziprasidone in ground food pellets containing 15% fat. Twenty control animals received no drugs. Blood samples were taken at week 14, 16, and 19. Locomotor activity and exploratory behavior were measured using the alcove test at weeks 15 and 17. The expression of the hypothalamic leptin receptor in rat brains was determined by using a Western blot. RESULTS: Rats medicated with haloperidol and ziprasidone showed a significantly decreased percentage weight gain and food consumption. We observed no differences in the alcove test, but locomotor activity was significantly reduced in the haloperidol group. Except for rats in the clozapine and ziprasidone groups, after 2 weeks of drug application, we found no changes in the leptin blood concentrations among the four groups or animals within each group. Moreover, we did not find specific differences in hypothalamic leptin receptor expression among the groups. CONCLUSION: We concluded that in male Wistar rats during this treatment period, the tested drugs did not act directly on the leptin regulatory system. We recommend further studies using long-term treatment of different rat strains

Sex-dependent behavioral effects and morphological changes in the hippocampus after prenatal invasive interventions in rats: implications for animal models of schizophrenia

OBJECTIVES: Although schizophrenia affects both human genders, there are gender-dependent differences with respect to age of onset, clinical characteristics, course and prognosis of the disease. METHODS: To investigate sex-dependent differences in motor coordination and activity as well as in cognitive and social behavior, we repeatedly tested female (n = 14) and male (n = 12) Fisher rats (postnatal days, PD 56-174) that had received intracerebroventricular injections of kainic acid as well as female (n = 15) and male (n = 16) control animals. The hippocampus was examined histologically. RESULTS: Compared to male controls, in the alcove test both female controls and female animals with prenatal intervention spent less time in a dark box before entering an unknown illuminated area. Again, animals that received prenatal injection (particularly females) made more perseveration errors in the T-maze alternation task compared to controls. Female rats exhibited a higher degree of activity than males, suggesting these effects to be sex-dependent. Finally, animals that received prenatal intervention maintained longer lasting social contacts. Histological analyses showed pyramidal cells in the hippocampal area CA3 (in both hemispheres) of control animals to be longer than those found in treated animals. Sex-dependent differences were found in the left hippocampi of control animals and animals after prenatal intervention. CONCLUSION: These results demonstrate important differences between males and females in terms of weight gain, response to fear, working memory and social behavior. We also found sex-dependent differences in the lengths of hippocampal neurons. Further studies on larger sample sets with more detailed analyses of morphological changes are required to confirm our data

Decreased reelin expression in the left prefrontal cortex (BA9) in chronic schizophrenia patients

Background: Reelin is under epigenetic control and has been reported to be decreased in cortical regions in schizophrenia. Methods: To establish if expression of reelin is altered in specific cortical, hippocampal or thalamic regions of schizophrenia patients, we measured gene expression of reelin in a postmortem study of elderly patients with schizophrenia and non-affected controls in both hemispheres differentiating between gray and white matter. We compared cerebral postmortem samples (dorsolateral prefrontal cortex BA9 and BA46, superior temporal cortex BA22, entorhinal cortex BA28, sensoric cortex BA1-3, hippocampus, CA4, mediodorsal nucleus of the thalamus) from 12 schizophrenia patients with 13 normal subjects investigating gene expression of reelin in the gray and white matter of both hemispheres by in situ-hybridization. Results: The left prefrontal area (BA9) of schizophrenia patients revealed a decreased expression of reelin-mRNA of 29.1% in the white (p = 0.022) and 13.6% in the gray matter (p = 0.007) compared to the control group. None of the other regions examined showed any statistically significant differences. Conclusion: Since reelin is responsible for migration and synapse formation, the decreased gene expression of reelin in the left prefrontal area of schizophrenia patients points to neurodevelopmental deficits in neuronal migration and synaptic plasticity. However, our study group was small, and results should be verified using larger samples. Copyright © 2012 S. Karger AG, Base

Drug attitude as predictor for effectiveness in first-episode schizophrenia: Results of an open randomized trial (EUFEST)

Effectiveness has become more and more important as a comprehensive outcome measure for (long-term) treatment in schizophrenia. Early predictors to identify patients at a high risk for not succeeding the initiated treatment would be very useful. Discontinuation of the initiated treatment was used as criterion for effectiveness and patients' drug attitude was shown to be predictive for non-adherence or discontinuation of long-term treatment in schizophrenia. Accordingly, the predictive validity of the Drug Attitude Inventory (DAI) for effectiveness should be evaluated. Based on a sub-sample of patients from the EUFEST study for whom DAI assessments were available significant predictors for effectiveness as measured by discontinuation of initiated treatment were identified based on a logistic and a Cox-regression analysis. A Receiver-Operating Characteristic- (ROC-) analysis was conducted for the DAI, prognostic / diagnostic parameters (sensitivity, specificity) were calculated and a cut-off value suggested. In a sample of 228 first-episode patients, the DAI score was the most powerful predictor for effectiveness (p<0.001) besides two other significant predictors (PANSS-positive score and sexual side effects). The ROC-analysis revealed an area under the curve of 0.64 (p<0.001). The suggested cut-off point of about 20 yielded a sensitivity of 70-75% and a specificity of 40-45%. Study results indicate that the Drug Attitude Inventory, filled in by patients early in treatment seems to be a valid predictor for effectiveness as measured by discontinuation of the initiated treatment. DAI scores could also serve as an (differential) indicator for the need of enhanced treatment monitoring. These findings have to be validated in other (first-episode) samples

Increased d-amino acid oxidase expression in the bilateral hippocampal CA4 of schizophrenic patients: a post-mortem study

An important risk gene in schizophrenia is d-amino acid oxidase (DAAO). To establish if expression of DAAO is altered in cortical, hippocampal or thalamic regions of schizophrenia patients, we measured gene expression of DAAO in a post-mortem study of elderly patients with schizophrenia and non-affected controls in both hemispheres differentiating between gray and white matter. We compared cerebral post-mortem samples (granular frontal cortex BA9, middle frontal cortex BA46, superior temporal cortex BA22, entorhinal cortex BA28, sensoric cortex BA1–3, hippocampus (CA4), mediodorsal nucleus of the thalamus) from 10 schizophrenia patients to 13 normal subjects investigating gene expression of DAAO in the gray and white matter of both hemispheres of the above-mentioned brain regions by in situ-hybridization. We found increased expression of DAAO-mRNA in the hippocampal CA4 of schizophrenic patients. Compared to the control group, both hemispheres of the hippocampus of schizophrenic patients showed an increased expression of 46% (right, P = 0.013) and 54% (left, P = 0.019), respectively. None of the other regions examined showed statistically significant differences in DAAO expression. This post-mortem study demonstrated increased gene expression of DAAO in the left and right hippocampus of schizophrenia patients. This increased expression could be responsible for a decrease in local d-serine levels leading to a NMDA-receptor hypofunction that is hypothesized to play a major role in the pathophysiology of schizophrenia. However, our study group was small and results should be verified using larger samples

Effects of haloperidol and clozapine on synapse-related gene expression in specific brain regions of male rats

We investigated the effects of clozapine and haloperidol, drugs that are widely used in the treatment of schizophrenia, on gene expression in six cortical and subcortical brain regions of adult rats. Drug treatments started at postnatal day 85 and continued over a 12-week period. Ten animals received haloperidol (1 mg/kg bodyweight) and ten received clozapine (20 mg/kg bodyweight) orally each day. Ten control rats received no drugs. The ten genes selected for this study did not belong to the dopaminergic or serotoninergic systems, which are typically targeted by the two substances, but coded for proteins of the cytoskeleton and proteins belonging to the synaptic transmitter release machinery. Quantitative real-time PCR was performed in the prelimbic cortex, cingulate gyrus (CG1) and caudate putamen and in the hippocampal cornu ammonis 1 (CA1), cornu ammonis 3 (CA3) and dentate gyrus. Results show distinct patterns of gene expression under the influence of the two drugs, but also distinct gene regulations dependent on the brain regions. Haloperidol-medicated animals showed statistically significant downregulation of SNAP-25 in CA3 (p = 0.0134) and upregulation of STX1A in CA1 (p = 0.0133) compared to controls. Clozapine-treated animals showed significant downregulation of SNAP-25 in CG1 (p = 0.0013). Our results clearly reveal that the drugs' effects are different between brain regions. These effects are possibly indirectly mediated through feedback mechanisms by proteins targeted by the drugs, but direct effects of haloperidol or clozapine on mechanisms of gene expression cannot be excluded

Effects of Aerobic Exercise on Metabolic Syndrome, Cardiorespiratory Fitness, and Symptoms in Schizophrenia Include Decreased Mortality

Schizophrenia is a severe psychiatric disorder with a lifetime prevalence of about 1%. People with schizophrenia have a 4-fold higher prevalence of metabolic syndrome than the general population, mainly because of antipsychotic treatment but perhaps also because of decreased physical activity. Metabolic syndrome is a risk factor for cardiovascular diseases, and the risk of these diseases is 2- to 3-fold higher in schizophrenia patients than in the general population. The suicide risk is also higher in schizophrenia, partly as a result of depression, positive, and cognitive symptoms of the disease. The higher suicide rate and higher rate of cardiac mortality, a consequence of the increased prevalance of cardiovascular diseases, contribute to the reduced life expectancy, which is up to 20 years lower than in the general population. Regular physical activity, especially in combination with psychosocial and dietary interventions, can improve parameters of the metabolic syndrome and cardiorespiratory fitness. Furthermore, aerobic exercise has been shown to improve cognitive deficits; total symptom severity, including positive and negative symptoms; depression; quality of life; and global functioning. High-intensity interval endurance training is a feasible and effective way to improve cardiorespiratory fitness and metabolic parameters and has been established as such in somatic disorders. It may have more beneficial effects on the metabolic state than more moderate and continuous endurance training methods, but to date it has not been investigated in schizophrenia patients in controlled, randomized trials. This review discusses physical training methods to improve cardiorespiratory fitness and reduce metabolic syndrome risk factors and symptoms in schizophrenia patients. The results of studies and future high-quality clinical trials are expected to lead to the development of an evidence-based physical training program for patients that includes practical recommendations, such as the optimal length and type of aerobic exercise programs and the ideal combination of exercise, psychoeducation, and individual weight management sessions

Predictors for symptom re-exacerbation after targeted stepwise drug discontinuation in first-episode schizophrenia Results of the first-episode study within the German research network on schizophrenia

Background: After a first episode in schizophrenia guidelines recommend antipsychotic maintenance treatment (MT) for at least 1 year. Recent RCTs on subsequent targeted intermittent treatment (IT) after stepwise drug discontinuation yielded noticeably higher relapse rates than during MT also in first-episode patients. Nevertheless, about 50% of patients remain stable under IT. Given the potential adverse effects of antipsychotics and the preference of many patients to discontinue drugs, valid predictors for the feasibility of IT are urgently needed to support decision making. Methods: Based on a one-year RCT phase comparing MT with IT in first-episode patients after 1 year of MT, conducted within the German Research Network on Schizophrenia (GRNS), predictors for deterioration under IT in 19 feasible patients were identified by logistic regression analysis. Results: Deterioration occurred in 10 patients (52.6%). Univariate analyses indicated a lower PANSS positive score after acute treatment as well as after one year of MT as significant predictors; in multivariate logistic regression, in addition to the lower PANSS positive score after acute treatment, reaching enduring remission and having had a deterioration both during MT evolved as significant predictors and indicate a higher risk for deterioration. Conclusions: Although limited by the small sample size, our findings suggest that patients who show a favorable response and full and enduring symptom remission during antipsychotic treatment, as well as those with marked deterioration despite MT should rather be recommended to remain on treatment because they are at higher risk for symptom re-exacerbation after (stepwise) drug discontinuation. (C) 2015 Elsevier B.V. All rights reserved

Rates and predictors of remission in first-episode schizophrenia within 1 year of antipsychotic maintenance treatment. Results of a randomized controlled trial within the German Research Network on Schizophrenia

Objective: Full and sustained symptom remission is a major treatment objective after a first-episode in schizophrenia. Findings regarding differences in remission between first-and second-generation antipsychotics are inconclusive. This study aimed to provide rates and predictors of remission in first-episode schizophrenia and to identify symptoms that prevent remission. Methods: Prevalence rates of symptomatic remission (symptom criteria only) and enduring remission (symptom and 6-month time criteria), defined according to Andreasen et al. (2005), were determined in first-episode patients participating in a RCT by the German Research Network on Schizophrenia (GRNS) that compared post-acute, 1-year maintenance treatment with risperidone or haloperidol. Respective predictors at baseline were identified by logistic and Cox regression analysis. Results: Prevalence rates were 91.5% for symptomatic remission (n = 152/166 eligible patients) and 58.6% for enduring remission (n = 65 of 111 patients who continued for at least 6 months; 39.2% of all 166 patients included), with no significant differences between risperidone and haloperidol in either type of remission. Enduring remission often was not reached because of negative symptoms: After 6 months, 40.5% of the patients had at least 1 negative symptom, whereas only 10.8% of the patients had persisting positive symptoms. Of the different predictors identified in univariate analyses, (lower) negative symptoms and participating in standardized psychological treatment remained significant in multivariate (stepwise forward) analyses for enduring remission. Conclusions: By far most of the first-episode patients reached a temporary state of full symptomatic remission within 1 year of antipsychotic treatment. However, only about 50% achieved sustained, enduring remission. Negative symptoms are still a major treatment obstacle to enduring remission in schizophrenia. (C) 2013 Elsevier B.V. All rights reserved