A. de Bartolomeis

A role for D-aspartate oxidase in schizophrenia and in schizophrenia-related symptoms induced by phencyclidine in mice

Increasing evidence points to a role for dysfunctional glutamate N-methyl-D-aspartate receptor (NMDAR) neurotransmission in schizophrenia. D-aspartate is an atypical amino acid that activates NMDARs through binding to the glutamate site on GluN2 subunits. D-aspartate is present in high amounts in the embryonic brain of mammals and rapidly decreases after birth, due to the activity of the enzyme D-aspartate oxidase (DDO). The agonistic activity exerted by D-aspartate on NMDARs and its neurodevelopmental occurrence make this D-amino acid a potential mediator for some of the NMDAR-related alterations observed in schizophrenia. Consistently, substantial reductions of D-aspartate and NMDA were recently observed in the postmortem prefrontal cortex of schizophrenic patients. Here we show that DDO mRNA expression is increased in prefrontal samples of schizophrenic patients, thus suggesting a plausible molecular event responsible for the D-aspartate imbalance previously described. To investigate whether altered D-aspartate levels can modulate schizophrenia-relevant circuits and behaviors, we also measured the psychotomimetic effects produced by the NMDAR antagonist, phencyclidine, in Ddo knockout mice (Ddo−/−), an animal model characterized by tonically increased D-aspartate levels since perinatal life. We show that Ddo−/− mice display a significant reduction in motor hyperactivity and prepulse inhibition deficit induced by phencyclidine, compared with controls. Furthermore, we reveal that increased levels of D-aspartate in Ddo−/− animals can significantly inhibit functional circuits activated by phencyclidine, and affect the development of cortico–hippocampal connectivity networks potentially involved in schizophrenia. Collectively, the present results suggest that altered D-aspartate levels can influence neurodevelopmental brain processes relevant to schizophrenia.

P.1.009 Effects of caffeine, nicotine and their combination with haloperidol on PSD molecules: relevance to psychiatric diseases

cultures from hippocampus and cortex of E18 mouse (C57BL/6J) embryos. Dendritic branching was analyzed (at weeks 1 and 2 post-infection) using Simple Neurite Tracer and Sholl analysis plugins for ImageJ/Fiji. We counted spines per 15mm dendritic segment and classified according to their morphologies [4]. Sholl analysis revealed reduced dendritic branching (Table 1) by overexpression of NOS1AP-L and NOS1APLDC20, supporting the findings that the NOS1AP aminoterminal domain also influences neurite development [5]. On the other hand, overexpression of each NOS1AP isoform/domain resulted in highly altered spine plasticity (Table 1) including significant reduction in mature spines (particularly thin and mushroom spines) and increased filopodia growth. We believe that the alteration in spine plasticity is primarily dependent on NOS1AP/NOS-I interaction, considering NOS1APLC20 overexpression was sufficient to disrupt spine development. NOS-IN133 overexpression had mild effects on spine development.

A Role for D-aspartate Oxidase in Schizophrenia and in Schizophrenia-related Symptoms Induced by Phencyclidine in Mice.

Introduction D-aspartate (D-Asp) is an atypical amino acid that binds to and activates NMDARs. D-Asp occurs abundantly in the embryonic brain of mammals and rapidly decreases after birth, due to the activity of the enzyme D-Aspartate Oxidase (DDO). The agonistic activity of D-Asp on NMDARs and its neurodevelopmental occurrence make this D-amino acid a potential mediator for NMDAR-related alterations observed in schizophrenia. Consistently, substantial reduction of D-Asp was observed in post-mortem schizophrenia brains. Aims We evaluated the potential contribution of D-Asp as neurodevelopmental modulator of brain circuits and behaviors relevant to schizophrenia. Objectives We analyzed DDO mRNA expression in the post-mortem prefrontal cortex of schizophrenic patients. Moreover, we treated knockout mice for Ddo gene ( Ddo -/- ) with the NMDAR antagonist phencyclidine to evaluate their schizophrenia-relevant behaviors and circuits. Finally, we assessed cortico-hippocampal connectivity of these mice. Methods DDO mRNA detection was performed by quantitative PCR. Phencyclidine-induced schizophrenia-like behaviours were assessed through motor activity and prepulse inhibition paradigms. Resting-state and pharmacological fMRI were used to evaluate functional circuits and connectivity. Results DDO mRNA expression is increased in frontal samples of schizophrenic patients. In mice, the absence of Ddo gene produces a significant reduction in phencyclidine-induced motor hyper-activity and prepulse inhibition deficit. Furthermore, increased levels of D-Asp in Ddo -/- animals significantly inhibit functional circuits activated by phencyclidine, and affect the development of cortico-hippocampal connectivity networks potentially involved in schizophrenia. Conclusions Our data suggest that D-Asp, through the regulation exerted by DDO, may have a role in the pathophysiology of schizophrenia.

EPA-1118 - Knowledge of the illness and its relations with quality of life, social functioning, cognitive performances, and adherence in psychotic patients: Toward effectiveness-focused interventions

Introduction Psychosocial factors are often underestimated in psychotic patients, although they may profoundly influence (and be influenced by) clinical presentation and effectiveness of therapeutic interventions in these people. Objectives To investigate relevance, relationship with clinical presentation and overall quality of life of multiple psychosocial factors in psychotic patients. Aims To evaluate whether knowledge about the illness and utilization of health services are defective in psychotic vs. non-psychotic patients and whether these correlates with the type of psychotic symptoms, cognitive performances, global social functioning, quality of life, and acceptance of pharmacotherapy. Methods Approximately 110 patients were enrolled after written informed consent. Patients were administered the Positive and Negative Syndrome Scale (PANSS), the Personal and Social Performance scale (PSP), the Drug Attitude Inventory (DAI), the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q). All patients were also screened for cognitive performances. Patients and relatives completed a questionnaire on knowledge about the illness and on the level of utilization of mental health services. Patients were subdivided in psychotic (cases) and non-psychotic (controls) based on their score on the PANSS. Results Psychotic patients and their relatives showed lower levels of knowledge about the illness. These features were associated with the other variables assessed in a very complex and multidimensional model of reciprocal influences. Conclusions Lack of response to pharmacological treatments and to overall therapeutic interventions in psychotic patients may also depend on multiple psychosocial factors, which may be carefully investigated and become the target of adjunctive, effectiveness-focused interventions.

EPA-1116 - Obesity affects cognitive performances even in the absence of obvious psychopathological alterations. a comparison with schizophrenia subjects and non-affected controls

Introduction Obesity has been associated with cognitive impairment. However, it is not clear whether cognitive impairment may depend on concomitant psychopathology, since several psychiatric conditions, e.g. schizophrenia, include cognitive deficits among their manifestations. Objectives To assess cognitive performances and psychopathology in obese patients, and to compare cognitive alterations in obese patients with those in schizophrenics and controls. Aims To compare cognitive performances in obese patients to normal percentiles. To provide an analysis of correlation with specific psychopathological domains. To evaluate whether cognitive performances in very obese patients were different from those in schizophrenia patients and non-affected controls. Methods 88 obese patients were included. Exclusion criteria were: axis I and II diagnosis; severe medical, neurological, or endocrinology conditions. Patients underwent an extensive battery of cognitive tests and completed the Toronto Alexithymia Scale (TAS-20), the Barratt Impulsiveness Scale (BIS-11), the Beck Depression Inventory (BDI), the State-Trait Anxiety Inventory (STAI). In the second part of the study, very obese patients (BMI>40; n=16) were compared for cognitive performances to schizophrenia patients (n=16) and non-affected controls (n=17). Results Obese patients performed at low percentiles ( Discussion Obese patients show cognitive alterations even in the absence of abnormal psychopathology. Very obese patients share cognitive alterations with schizophrenia patients, which may imply common neurobiological basis.

P.1.031 Expression of glucose metabolism genes in a psychosis model: a molecular link between NMDA receptor hypofunction and metabolism disorders?

of bisulfite-treated DNA (EpigenDx, Worcester MA). Altogether, we examined the methylation level across 39 CpG sites in the GR exon 1F promoter region for each subject. Two genes were genotyped; the 5HTTLPR and the ESR1. All statistical tests were carried out using SPSS version 15. A linear regression model was used to ascertain the effects of sex, GR methylation level and genes on stress response. Statistical normality of the data was checked using the Kolmogorov-Smirnov test. Results: Marked individual differences were observed in methylation levels of GR exon 1F at individual CpG sites for females and males. Overall, women showed significantly greater methylation levels than did men (t = 2.538, p = 0.013). There was a correlation between total cortisol output (area under the curve, AUC) and average methylation level at GR exon 1F in female subjects (R2D= 0.214, F(1,44) = 11.997, p = 0.001) accounting for 21.4% of the variance. Additionally, variations in the ESR1 and the 5-HTTLPR genes were significant predictors of AUC. A significant main effect of 5-HTTLPR (R2D= 0.172, F1,42 = 12.032, p = 0.001) and ESR1 (R2D= 0.132, F2,40 = 5.634, p = 0.007) was observed on AUC but there was no interaction between methylation and either gene. The full model accounted for nearly half of the variance (48%) in total cortisol output. Conclusions: We provide the first evidence that accumulated epigenetic changes at the peripheral GR exon 1F correlate with HPAA reactivity. Importantly, women show significantly greater methylation across the GR promoter exon 1F compared to men. The averaged methylation levels and each of the two polymorphisms are highly significant independent predictors of total cortisol response (AUC) in the TSST. These findings have important implications for understanding the molecular mechanisms underlying gender differences in stressrelated mental health disorders, and underscore the unique value of modeling both epigenetic and genetic information in conferring vulnerability to stress.

Postsynaptic density protein gene expression after typical or atypical antipsychotics administration

The affinities of antipsychotics at receptor and re-uptake sites were compared to deduce differences that might underlie the low incidence of weight gain observed with ziprasidone compared with other novel antipsychotics. Ziprasidone, olanzapine, risperidone, clozapine, quetiapine and haloperidol were evaluated in human or bovine radioligand binding and rat synaptosomal re-uptake studies. Relative to D2 receptor affinities, clozapine has higher affinity for 5HT2A&C, ml, HI, ~-1 and 7-2; olanzapine for 5HT2A&C, ml, and H1; risperidone for 5HT2A and ct-1; and quetiapine for H1, ml, and ~-1 receptors. In contrast, ziprasidone has higher affinity for the combination of serotonin 5HT2A&C, 5HT1A, and 5HT1D and reduced affinity for ~-1 receptors. Like risperidone, ziprasidone has reduced relative affinity for H1 receptors. Only ziprasidone moderately inhibits 5HT and NE re-uptake and has high affinity for 5HT1D receptors. In studies of patients with psychotic disorders ziprasidone is associated with significantly less weight gain than clozapine, olanzapine and risperidone and also less than quetiapine. The differences observed with ziprasidone suggest that the reduced H1 and ~-1 receptor binding affinities as well as its unique profile of potent 5HT receptor interactions (including 5HT1A agonism) and its moderate inhibition of 5HT and NE neuronal re-uptake all might contribute to its low potential for weight gain.