Maurizio De Vanna

Low serum truncated-BDNF isoform correlates with higher cognitive impairment in schizophrenia

Brain-derived neurotrophic factor (BDNF) is a key factor in learning and memory. Altered BDNF-signalling is thought to contribute to the pathogenesis of schizophrenia (SZ) especially in relation to cognitive deficits. However, analysis of serum BDNF as a potential biomarker in schizophrenia has provided controversial data. We hypothesized that these confounding results might be due to a differential regulation of BDNF precursor pro-BDNF (32 KDa) and proteolytic products mature (mat-BDNF; 14 KDa), and truncated-BDNF (28 KDa). Accordingly, we investigated the serum abundance of these BDNF isoforms and its relationship with cognitive impairment in schizophrenia. Schizophrenia was diagnosed with PANSS test. Abbreviated cognitive assessment included tests for attention, perceptual-motor skills, processing speed and memory. Using an ELISA assay, we found a slight reduction in serum BDNF levels in SZ patients (n = 40) with respect to healthy controls (HC, n = 40; p = 0.018). Western-blot analysis revealed increased serum pro-BDNF and mat-BDNF and reduced truncated-BDNF (p < 0.001) in SZ with respect to HC. Patients with an increase in pro-BDNF (n = 15/40) or mat-BDNF (n = 9/40) higher than the HC mean + 2 Standard Deviations (SD) also had >2SD reduction of truncated-BDNF (n = 27/40). Reduced truncated-BDNF correlated significantly with higher positive and lower negative PANNS scores and a worst performance in all cognitive assays but not with antipsychotic type. Measurement of serum truncated-BDNF abundance predicted for high cognitive deficits with sensitivity = 67.5%, specificity = 97.5%, Negative Predictive Value = 75% and Positive Predictive Value = 96.4%. These results suggest deficiency in pro-BDNF processing as a possible biological mechanism underlying schizophrenia with cognitive impairment.

Is Altered BDNF Biosynthesis a General Feature in Patients with Cognitive Dysfunctions

Severe cognitive deficits are a frequent outcome of both neurodegenerative and neurodevelopmental disorders. In the attempt to define new clinical biomarkers, current research trends aim at the identification of common molecular features in these pathologies rather than searching for differences. Brain-derived neurotrophic factor (BDNF) has attracted great interest as possible biomarker because of its key role in synaptic remodeling during cognitive processes. BDNF undergoes proteolytic processing and studies in animal models have highlighted that different forms of learning and memory require either the proBDNF precursor or the mature BDNF form. Significantly, an altered expression of BDNF forms was found in postmortem brains and serum from patients with schizophrenia, Alzheimer’s disease and mood disorders. Based on these studies, this review puts forward the hypothesis that abnormalities in proBDNF or mBDNF biosynthesis may correspond to different cognitive dysfunctions in these brain diseases, while the role of truncated BDNF remains unknown.

Insight in persons with schizophrenia: effects of switching from conventional neuroleptics to atypical antipsychotics.

The primary aim of our study is to evaluate the level of insight during the switch from a classical antipsychotic drug to a atypical neuroleptic. Twenty-two schizophrenic patients were admitted to the study, 9 were male and 13 were female. Standardized questionnaire were: Scale for Assessment of Negative Symptoms (SANS), Scale for Assessment of Positive Symptoms (SAPS), Brief Psychiatric Rating Scale (BPRS) and Schedule for Assessing the three components of Insight (SAI). All patients were receiving haloperidol at time of recruitment. Eight patients were switched to clozapine, 3 to risperidone and 11 to olanzapine. The global function, measured with BPRS, increased after administration of atypical antipsychotics. The positive and negative symptoms were reduced. The level of insight was increased after the administration of the atypical antipsychotics. The cognitive effect of the atypical antipsychotics changed the level of insight and augmented the compliance.

Recent life events and attempted suicide

The contextual method was used to identify the incidence of recent life events and difficulties among 50 suicide attempters compared with a control group selected at random from the general population. Suicide attempters experienced a significantly greater incidence of major life events, although for all life events irrespective of stressfulness, and for independent events the differences were not significant. The overall incidence of difficulties was also higher among suicide attempters. Finally, the results suggest a vulnerability effect as far as three factors are concerned: early loss of/separation from one or both parents, absence of paid employment and living in a nuclear family.

Role of Lormetazepam in the Treatment of Insomnia in the Elderly

AbstractBackground and objective: Sleep architecture changes with age, both in terms of efficiency and total duration of sleep. Hypnotic benzodiazepines promote rapid onset of sleep, uninterrupted sleep and longer duration of sleep in the absence of carryover sedation the following morning; therefore, these may be appropriate for use in older patients. This study was performed to evaluate the efficacy and safety of lormetazepam in elderly patients with primary insomnia when used in association with sleep hygiene training (SHT). The impact of restored sleep on daily sleepiness was also investigated. Patients and methods: In this open-label study, 30 elderly outpatients with insomnia were randomised to receive 2 weeks of treatment with lormetazepam 0.5mg + SHT or SHT alone, followed by a 1-week observation period. Details on sleep latency, number of awakenings and freshness on awakening were recorded by patients in a daily sleep diary. The Epworth Sleepiness Scale (ESS) and Stanford Sleepiness Scale (SSS) were used to measure daily sleepiness. Results: Addition of lormetazepam to SHT improved all sleep parameters measured compared with SHT alone. Mean duration of sleep improved significantly from baseline (mean rank = 1.00) in the lormetazepam + SHT group after 2 weeks of treatment (mean rank 2.87; Friedmann test = 27.448; p < 0.001), but declined significantly in the group receiving SHT alone (from mean rank 2.33 to 1.57; Friedmann test = 6.465; p < 0.05). Mean duration of sleep increased by approximately 150 minutes each night in the lormetazepam + SHT group but decreased by more than 30 minutes in the SHT-only group. Improvement in sleep quality from baseline was statistically significant only in the lormetazepam + SHT group: for both deepness of sleep and the perception of awakening refreshed, mean scores increased from approximately 3 at baseline to approximately 8 (on a scale of 1–10) after 2 weeks in this group. Sleep latency also decreased significantly in the lormetazepam + SHT group: after 2 weeks, on average patients were awakening less than once per night. SSS and ESS scores also improved significantly in the lormetazepam + SHT group; in contrast, in the SHT-only group, the mean ESS score worsened significantly from baseline and the mean SSS score remained relatively constant. No rebound insomnia was reported during follow-up in patients in the lormetazepam group. Vital signs did not change from baseline and no adverse events were reported for either group. Conclusion: Management of insomnia in the elderly appears to have a better outcome when pharmacotherapy is combined with SHT rather than SHT alone. The earlier improvement in sleep quality with lormetazepam when used in combination with a sleep training programme may help to maintain adherence to treatment.

Repeated suicidal behaviour: Stressful life events and 5-HTTLPR genetic polymorphism

Stressful life events and dysregulated mono-aminergic neurotransmission have been associated with suicidal behaviour. The aim of this investigation was to analyze suicidal behaviour in multiple attempters in relation to the stressful life events, and to the polymorphism of the serotonin transporter (SERT) gene. Multiple suicide attempters, admitted to the University Psychiatric Clinic, were interviewed for the number of previous suicide attempts and for the occurrence of stressful life events, recorded in a Life History Calendar. The patients were further genotyped for 5-HTTLPR polymorphism of SERT. The number of suicide attempts was found to be significantly correlated with the number of negative life events experienced during the 6 months preceding each suicide attempt. The L/L genotype was associated with a reduced number of multiple suicide attempts. These results should prompt future study with a larger number of subjects to further investigate the interaction of genetic and environmental factors in repeated suicidal behaviour.