Progranulin Gene Variability and Plasma Levels in Bipolar Disorder and Schizophrenia

Basing on the assumption that frontotemporal lobar degeneration (FTLD), schizophrenia and bipolar disorder (BPD) might share common aetiological mechanisms, we analyzed genetic variation in the FTLD risk gene progranulin (GRN) in a German population of patients with schizophrenia (n = 271) or BPD (n = 237) as compared with 574 age-, gender- and ethnicity-matched controls. Furthermore, we measured plasma progranulin levels in 26 German BPD patients as well as in 61 Italian BPD patients and 29 matched controls

AI is a viable alternative to high throughput screening: a 318-target study

: High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

Reduced Treatment-Emergent Sexual Dysfunction as a Potential Target in the Development of New Antidepressants

Pleasurable sexual activity is an essential component of many human relationships, providing a sense of physical, psychological, and social well-being. Epidemiological and clinical studies show that depressive symptoms and depressive illness are associated with impairments in sexual function and satisfaction, both in untreated and treated patients. The findings of randomized placebo-controlled trials demonstrate that most of the currently available antidepressant drugs are associated with the development or worsening of sexual dysfunction, in a substantial proportion of patients. Sexual difficulties during antidepressant treatment often resolve as depression lifts but can endure over long periods and may reduce self-esteem and affect mood and relationships adversely. Sexual dysfunction during antidepressant treatment is typically associated with many possible causes, but the risk and type of dysfunction vary with differing compounds and should be considered when making decisions about the relative merits and drawbacks of differing antidepressants. A range of interventions can be considered when managing patients with sexual dysfunction associated with antidepressants, including the prescription of phosphodiesterase-5 inhibitors, but none of these approaches can be considered “ideal.” As treatment-emergent sexual dysfunction is less frequent with certain drugs, presumably related to differences in their pharmacological properties, and because current management approaches are less than ideal, a reduced burden of treatment-emergent sexual dysfunction represents a tolerability target in the development of novel antidepressants

Epigenetic modulation of BDNF gene: Differences in DNA methylation between unipolar and bipolar patients

Background The brain derived neurotrophic factor (BDNF) gene and its epigenetic regulation have been repeatedly implicated in the pathophysiology of mood disorders. Following previous investigation in the field, we further investigated differences in BDNF promoter gene methylation in patients with mood disorders, comparing unipolar and bipolar subjects, on the basis of illness phase, gender, age and psychotropic prescription. Methods 154 patients (43 MDD; 61 BD I; 50 BD II), on stable pharmacological treatment, and 44 age-matched, healthy controls were recruited. BDNF methylation levels from peripheral blood mononuclear cells (PBMCs) were compared by analysis of variance followed by Bonferroni's post-hoc test. Results Similar, higher levels of BDNF gene promoter methylation were found in BD II and MDD patients, compared to BD I subjects (P<0.01). When stratified on the basis of mood status, methylation levels of depressed patients were significantly higher, compared to the levels of manic/mixed patients (P<0.01). While gender and age did not seem to influence methylation levels of BDNF gene promoter, patients on lithium and valproate showed overall lower levels. Limitations: Cross-sectional analysis using PBMCs with further investigation with larger samples, including drug-na\uefve patients, needed to replicate findings in neuronal cells. Conclusions Present data confirm our previous results of higher methylation levels in BD II (compared to BD I) and MDD patients (compared to controls). A closer relationship between BD II and MDD, compared to BD I patients as well an association of lower methylation levels with the presence of mania/mixed state, compared to the depressive phase, was observed

Altered prefrontal cortex activity during working memory task in Bipolar Disorder: A functional Magnetic Resonance Imaging study in euthymic bipolar I and II patients

Working memory (WM) deficits are among the most frequently impaired cognitive domains in patients with Bipolar Disorder (BD), being considered promising cognitive endophenotype of the disorder. However, the related neurobiological correlates still deserve further investigation. The present study was aimed to explore whether dorsolateral prefrontal cortex (DLPFC) activity during WM processing was abnormal in euthymic bipolar patients and may represent a potential trait-related phenotype associated with the disorder. METHODS: Using 3 Tesla functional Magnetic Resonance Imaging (3T fMRI), we studied 28 euthymic bipolar patients (15 BDI and 13 BDII), and 27 healthy controls (HCs), matched for a series of socio-demographic variables, while performing the N-back task for WM assessment. RESULTS: We found that euthymic bipolar patients showed increased right middle frontal gyrus engagement compared with HCs (FWE-corrected p = 1 × 10(-3)), regardless of WM load, and in spite of similar WM behavioral performance between groups. In particular, BDI patients had greater BOLD signal change compared to HCs (post-hoc Tukey HSD, p = 1 × 10(-3)), while BDII patients expressed an intermediate pattern of activation between BDI patients and HCs. No other significant effects were detected in the corrected whole-brain analysis. LIMITATIONS: Sample size, cross-sectional assessment and potential influence of some clinical variables. CONCLUSIONS: Results provide direct evidence of a primary physiological abnormality in DLPFC function in BDI and II, even in the absence of behavioral differences with HCs. Such exaggerated fMRI response suggests inefficient WM processing in prefrontal circuitry, and further studies are warranted to investigate whether the dysfunction is related to the genetic risk for the disorder. Copyright © 2015 Elsevier B.V. All rights reserved

Regulation of gene transcription in bipolar disorders: Role of DNA methylation in the relationship between prodynorphin and brain derived neurotrophic factor

Bipolar Disorder (BD) is a prevalent and disabling condition, determined by gene-environment interactions, possibly mediated by epigenetic mechanisms. The present study aimed at investigating the transcriptional regulation of BD selected target genes by DNA methylation in peripheral blood mononuclear cells of patients with a DSM-5 diagnosis of type I (BD-I) and type II (BD-II) Bipolar Disorders (n = 99), as well as of healthy controls (CT, n = 42). The analysis of gene expression revealed prodynorphin (PDYN) mRNA levels significantly reduced in subjects with BD-II but not in those with BD-I, when compared to CT. Other target genes (i.e. catechol-O-methyltransferase (COMT), glutamate decarboxylase (GAD67), serotonin transporter (SERT) mRNA levels remained unaltered. Consistently, an increase in DNA methylation at PDYN gene promoter was observed in BD-II patients vs CT. After stratifying data on the basis of pharmacotherapy, patients on mood-stabilizers (i.e., lithium and anticonvulsants) were found to have lower DNA methylation at PDYN gene promoter. A significantly positive correlation in promoter DNA methylation was observed in all subjects between PDYN and brain derived neurotrophic factor (BDNF), whose methylation status had been previously found altered in BD. Moreover, among key genes relevant for DNA methylation establishment here analysed, an up-regulation of DNA Methyl Transferases 3b (DNMT3b) and of the methyl binding protein MeCP2 (methyl CpG binding protein 2) mRNA levels was also observed again just in BD-II subjects. A clear selective role of DNA methylation involvement in BD-II is shown here, further supporting a role for BDNF and its possible interaction with PDYN. These data might be relevant in the pathophysiology of BD, both in relation to BDNF and for the improvement of available treatments and development of novel ones that modulate epigenetic signatures

Italian patients with more recent onset of Major Depressive Disorder have a shorter duration of untreated illness

Background: Previous investigation on the duration of untreated illness (DUI) in patients with Major Depressive Disorder (MDD) revealed a different latency to first antidepressant treatment, with adverse consequences in terms of outcome for individuals with a longer DUI. Recent reports, moreover, documented a reduced DUI, as observed with the passage of time, in patients with different psychiatric disorders. Hence, the present study was aimed to assess DUI and related variables in a sample of Italian patients with MDD as well as to investigate potential differences in subjects with onset before and after 2000. Methods: An overall sample of 188 patients with MDD was assessed through a specific questionnaire investigating DUI and other variables related to the psychopathological onset and latency to first antidepressant treatment, after dividing them in two different subgroups on the basis of their epoch of onset. Results: The whole sample showed a mean DUI of approximately 4.5 years, with patients with more recent onset showing a significantly shorter latency to treatment compared with the other group (27.1\ub142.6 vs 75.8\ub1105.2 months, P<.05). Other significant differences emerged between the two subgroups, in terms of rates of onset-related stressful events and benzodiazepine prescription, respectively, higher and lower in patients with more recent onset. Conclusions: Our findings indicate a significant DUI reduction in MDD patients whose onset occurred after vs before 2000, along with other relevant differences in terms of onset-related correlates and first pharmacotherapy. Further studies with larger samples are warranted to confirm the present findings in Italy and other countries