Genome-wide analyses reveal a potential role for the MAPT, MOBP, and APOE loci in sporadic frontotemporal dementia.

Frontotemporal dementia (FTD) is the second most common cause of early-onset dementia after Alzheimer disease (AD). Efforts in the field mainly focus on familial forms of disease (fFTDs), while studies of the genetic etiology of sporadic FTD (sFTD) have been less common. In the current work, we analyzed 4,685 sFTD cases and 15,308 controls looking for common genetic determinants for sFTD. We found a cluster of variants at the MAPT (rs199443; p = 2.5 × 10-12, OR = 1.27) and APOE (rs6857; p = 1.31 × 10-12, OR = 1.27) loci and a candidate locus on chromosome 3 (rs1009966; p = 2.41 × 10-8, OR = 1.16) in the intergenic region between RPSA and MOBP, contributing to increased risk for sFTD through effects on expression and/or splicing in brain cortex of functionally relevant in-cis genes at the MAPT and RPSA-MOBP loci. The association with the MAPT (H1c clade) and RPSA-MOBP loci may suggest common genetic pleiotropy across FTD and progressive supranuclear palsy (PSP) (MAPT and RPSA-MOBP loci) and across FTD, AD, Parkinson disease (PD), and cortico-basal degeneration (CBD) (MAPT locus). Our data also suggest population specificity of the risk signals, with MAPT and APOE loci associations mainly driven by Central/Nordic and Mediterranean Europeans, respectively. This study lays the foundations for future work aimed at further characterizing population-specific features of potential FTD-discriminant APOE haplotype(s) and the functional involvement and contribution of the MAPT H1c haplotype and RPSA-MOBP loci to pathogenesis of sporadic forms of FTD in brain cortex.

Using integrated meta-omics to appreciate the role of the gut microbiota in epilepsy.

The way the human microbiota may modulate neurological pathologies is a fascinating matter of research. Epilepsy is a common neurological disorder, which has been largely investigated in correlation with microbiota health and function. However, the mechanisms that regulate this apparent connection are scarcely defined, and extensive effort has been conducted to understand the role of microbiota in preventing and reducing epileptic seizures. Intestinal bacteria seem to modulate the seizure frequency mainly by releasing neurotransmitters and inflammatory mediators. In order to elucidate the complex microbial contribution to epilepsy pathophysiology, integrated meta-omics could be pivotal. In fact, the combination of two or more meta-omics approaches allows a multifactorial study of microbial activity within the frame of disease or drug treatments. In this review, we provide information depicting and supporting the use of multi-omics to study the microbiota-epilepsy connection. We described different meta-omics analyses (metagenomics, metatranscriptomics, metaproteomics and metabolomics), focusing on current technical challenges in stool collection procedures, sample extraction methods and data processing. We further discussed the current advantages and limitations of using the integrative approach of multi-omics in epilepsy investigations.

Genome-wide association identifies the first risk loci for psychosis in Alzheimer disease.

Psychotic symptoms, defined as the occurrence of delusions or hallucinations, are frequent in Alzheimer disease (AD with psychosis, AD + P). AD + P affects ~50% of individuals with AD, identifies a subgroup with poor outcomes, and is associated with a greater degree of cognitive impairment and depressive symptoms, compared to subjects without psychosis (AD - P). Although the estimated heritability of AD + P is 61%, genetic sources of risk are unknown. We report a genome-wide meta-analysis of 12,317 AD subjects, 5445 AD + P. Results showed common genetic variation accounted for a significant portion of heritability. Two loci, one in ENPP6 (rs9994623, O.R. (95%CI) 1.16 (1.10, 1.22), p = 1.26 × 10-8) and one spanning the 3'-UTR of an alternatively spliced transcript of SUMF1 (rs201109606, O.R. 0.65 (0.56-0.76), p = 3.24 × 10-8), had genome-wide significant associations with AD + P. Gene-based analysis identified a significant association with APOE, due to the APOE risk haplotype ε4. AD + P demonstrated negative genetic correlations with cognitive and educational attainment and positive genetic correlation with depressive symptoms. We previously observed a negative genetic correlation with schizophrenia; instead, we now found a stronger negative correlation with the related phenotype of bipolar disorder. Analysis of polygenic risk scores supported this genetic correlation and documented a positive genetic correlation with risk variation for AD, beyond the effect of ε4. We also document a small set of SNPs likely to affect risk for AD + P and AD or schizophrenia. These findings provide the first unbiased identification of the association of psychosis in AD with common genetic variation and provide insights into its genetic architecture.

Polygenic risk scores for neuropsychiatric, inflammatory, and cardio-metabolic traits highlight possible genetic overlap with suicide attempt and treatment-emergent suicidal ideation.

Suicide is the second cause of death among youths. Genetics may contribute to suicidal phenotypes and their co-occurrence in other neuropsychiatric and medical conditions. Our study aimed to investigate the association of polygenic risk scores (PRSs) for 24 neuropsychiatric, inflammatory, and cardio-metabolic traits/diseases with suicide attempt (SA) or treatment-worsening/emergent suicidal ideation (TWESI). PRSs were computed based on summary statistics of genome-wide association studies. Regression analyses were performed between PRSs and SA or TWESI in four clinical cohorts. Results were then meta-analyzed across samples, including a total of 688 patients with SA (Neff  = 2,258) and 214 with TWESI (Neff  = 785). Stratified genetic covariance analyses were performed to investigate functionally cross-phenotype PRS associations. After Bonferroni correction, PRS for major depressive disorder (MDD) was associated with SA (OR = 1.24; 95% CI = 1.11-1.38; p = 1.73 × 10-4 ). Nominal associations were shown between PRSs for coronary artery disease (CAD) (p = 4.6 × 10-3 ), loneliness (p = .009), or chronic pain (p = .016) and SA, PRSs for MDD or CAD and TWESI (p = .043 and p = .032, respectively). Genetic covariance between MDD and SA was shown in 86 gene sets related to drugs having antisuicidal effects. A higher genetic liability for MDD may underlie a higher SA risk. Further, but milder, possible modulatory factors are genetic risk for loneliness and CAD.

Technological tools and strategies for culturing human gut microbiota in engineered in vitro models.

The gut microbiota directly impacts the pathophysiology of different human body districts. Consequently, microbiota investigation is an hot topic of research and its in vitro culture has gained extreme interest in different fields. However, the high sensitivity of microbiota to external stimuli, such as sampling procedure, and the physicochemical complexity of the gut environment make its in vitro culture a challenging task. New engineered microfluidic gut-on-a-chip devices have the potential to model some important features of the intestinal structure, but they are usually unable to sustain culture of microbiota over an extended period of time. The integration of gut-on-a-chip devices with bioreactors for continuous bacterial culture would lead to fast advances in the study of microbiota-host crosstalk. In this review, we summarize the main technologies for the continuous culture of microbiota as upstream systems to be coupled with microfluidic devices to study bacteria-host cells communication. The engineering of integrated microfluidic platforms, capable of sustaining both anaerobic and aerobic cultures, would be the starting point to unveil complex biological phenomena proper of the microbiota-host crosstalks, paving to way to multiple research and technological applications.

Genomic dissection of pod shattering in common bean: mutations at non-orthologous loci at the basis of convergent phenotypic evolution under domestication of leguminous species.

The complete or partial loss of shattering ability occurred independently during the domestication of several crops. Therefore, the study of this trait can provide an understanding of the link between phenotypic and molecular convergent evolution. The genetic dissection of 'pod shattering' in Phaseolus vulgaris is achieved here using a population of introgression lines and next-generation sequencing techniques. The 'occurrence' of the indehiscent phenotype (indehiscent versus dehiscent) depends on a major locus on chromosome 5. Furthermore, at least two additional genes are associated with the 'level' of shattering (number of shattering pods per plant: low versus high) and the 'mode' of shattering (non-twisting versus twisting pods), with all of these loci contributing to the phenotype by epistatic interactions. Comparative mapping indicates that the major gene identified on common bean chromosome 5 corresponds to one of the four quantitative trait loci for pod shattering in Vigna unguiculata. None of the loci identified comprised genes that are homologs of the known shattering genes in Glycine max. Therefore, although convergent domestication can be determined by mutations at orthologous loci, this was only partially true for P. vulgaris and V. unguiculata, which are two phylogenetically closely related crop species, and this was not the case for the more distant P. vulgaris and G. max. Conversely, comparative mapping suggests that the convergent evolution of the indehiscent phenotype arose through mutations in different genes from the same underlying gene networks that are involved in secondary cell-wall biosynthesis and lignin deposition patterning at the pod level.

Increased transcription of transglutaminase 1 mediates neuronal death in in vitro models of neuronal stress and Aß1-42-mediated toxicity.

Alzheimer's disease (AD) is the most common cause of dementia. At the pre-symptomatic phase of the disease, the processing of the amyloid precursor protein (APP) produces toxic peptides, called amyloid-ß 1-42 (Aß 1-42). The downstream effects of Aß 1-42 production are not completely uncovered. Here, we report the involvement of transglutaminase 1 (TG1) in in vitro AD models of neuronal toxicity. TG1 was increased at late stages of the disease in the hippocampus of a mouse model of AD and in primary cortical neurons undergoing stress. Silencing of TGM1 gene was sufficient to prevent Aß-mediated neuronal death. Conversely, its overexpression enhanced cell death. TGM1 upregulation was mediated at the transcriptional level by an activator protein 1 (AP1) binding site that when mutated halted TGM1 promoter activation. These results indicate that TG1 acts downstream of Aß-toxicity, and that its stress-dependent increase makes it suitable for pharmacological intervention.

Psychiatric disorders and SLC6A4 gene variants: possible effects on alcohol dependence and alzheimer's disease.

Serotoninergic system is one of the most important neurotransmission systems investigated in the field of psychiatry. Extensive evidence reveals how alterations of this system, and especially of the SLC6A4 gene, may be associated with psychiatric disorders. In this study we aimed to evaluate the pleiotropic nature of SLC6A4 alterations and their association with the overall risk of brain diseases rather than disorder-specific. SLC6A4 variants, namely 5HTTLPR, STin2, rs2066713, rs25531, rs4251417, rs6354 and rs7224199 were investigated in 4 independent cohorts of subjects with specific psychiatric disorders, including Alcohol dependence disorder (ALC), Alzheimer disease (ALZ), Schizophrenia (SCZ) and Bipolar disorder (BPD). Other variables (biochemical parameters and Psychiatric scales scores) were also tested for association. SLC6A4 polymorphisms are not associated with the risk of developing major psychiatric disorders (SCZ and BPD); however some signals were detected in ALC (HTTLPR pd = 9.25 × 10-03, pr = 7.24 × 10-03; rs2066713 pd = 6.35 × 10-08; rs25531 pd = 2.95 × 10-02; rs4251417 pd = 2.46 × 10-03), and ALZ (rs6354 pr = 1.22 × 10-02; rs7224199 pd = 1.00 × 10-08, pr = 2.65 × 10-02) cohorts. Some associations were also observed on exploratory analyses. Our findings did not reveal any major influence on SCZ and BPD development; On the other hand, some alteration of the SLC6A4 sequence were associated with an increased risk of ALC and ALZ disorders, suggesting common pathways. The results of this study should be carefully interpreted since it suffers of some inherent limitations (e.g. cohort size, slight ethnic heterogeneity). Further analyses may provide better detail on the molecular processes behind SLC6A4 alterations.

Correction to: Psychiatric disorders and SLC6A4 gene variants: possible effects on alcohol dependence and alzheimer's disease.

The following authors have double affiliations: Stefania Boccia, Marco Di Nicola and they should read.

Genome-wide association study of treatment-resistance in depression and meta-analysis of three independent samples.

BACKGROUND: Treatment-resistant depression (TRD) is the most problematic outcome of depression in terms of functional impairment, suicidal thoughts and decline in physical health.AimsTo investigate the genetic predictors of TRD using a genome-wide approach to contribute to the development of precision medicine. METHOD: A sample recruited by the European Group for the Study of Resistant Depression (GSRD) including 1148 patients with major depressive disorder (MDD) was characterised for the occurrence of TRD (lack of response to at least two adequate antidepressant treatments) and genotyped using the Infinium PsychArray. Three clinically relevant patient groups were considered: TRD, responders and non-responders to the first antidepressant trial, thus outcomes were based on comparisons of these groups. Genetic analyses were performed at the variant, gene and gene-set (i.e. functionally related genes) level. Additive regression models of the outcomes and relevant covariates were used in the GSRD participants and in a fixed-effect meta-analysis performed between GSRD, STAR*D (n = 1316) and GENDEP (n = 761) participants. RESULTS: No individual polymorphism or gene was associated with TRD, although some suggestive signals showed enrichment in cytoskeleton regulation, transcription modulation and calcium signalling. Two gene sets (GO:0043949 and GO:0000183) were associated with TRD versus response and TRD versus response and non-response to the first treatment in the GSRD participants and in the meta-analysis, respectively (corrected P = 0.030 and P = 0.027). CONCLUSIONS: The identified gene sets are involved in cyclic adenosine monophosphate mediated signal and chromatin silencing, two processes previously implicated in antidepressant action. They represent possible biomarkers to implement personalised antidepressant treatments and targets for new antidepressants.Declaration of interestD.S. has received grant/research support from GlaxoSmithKline and Lundbeck; has served as a consultant or on advisory boards for AstraZeneca, Bristol-Myers Squibb, Eli Lilly, Janssen and Lundbeck. S.M. has been a consultant or served on advisory boards for: AstraZeneca, Bristol-Myers Squibb, Forest, Johnson & Johnson, Leo, Lundbeck, Medelink, Neurim, Pierre Fabre, Richter. S.K. has received grant/research support from Eli Lilly, Lundbeck, Bristol-Myers Squibb, GlaxoSmithKline, Organon, Sepracor and Servier; has served as a consultant or on advisory boards for AstraZeneca, Bristol-Myers Squibb, GlaxoSmithKline, Eli Lilly, Lundbeck, Pfizer, Organon, Schwabe, Sepracor, Servier, Janssen and Novartis; and has served on speakers' bureaus for AstraZeneca, Eli Lily, Lundbeck, Schwabe, Sepracor, Servier, Pierre Fabre, Janssen and Neuraxpharm. J.Z. has received grant/research support from Lundbeck, Servier, Brainsway and Pfizer, has served as a consultant or on advisory boards for Servier, Pfizer, Abbott, Lilly, Actelion, AstraZeneca and Roche and has served on speakers' bureaus for Lundbeck, Roch, Lilly, Servier, Pfizer and Abbott. J.M. is a member of the Board of the Lundbeck International Neuroscience Foundation and of Advisory Board of Servier. A.S. is or has been consultant/speaker for: Abbott, AbbVie, Angelini, Astra Zeneca, Clinical Data, Boehringer, Bristol Myers Squibb, Eli Lilly, GlaxoSmithKline, Innovapharma, Italfarmaco, Janssen, Lundbeck, Naurex, Pfizer, Polifarma, Sanofi and Servier. C.M.L. receives research support from RGA UK Services Limited.

Corrected QT Interval Prolongation in Psychopharmacological Treatment and Its Modulation by Genetic Variation.

Several antipsychotics and antidepressants have been associated with electrocardiogram alterations, the most clinically relevant of which is the heart rate-corrected QT interval (QTc) prolongation, a risk factor for sudden cardiac death. Genetic variants influence drug-induced QTc prolongation and can provide valuable information for precision medicine. The effect of genetic variants on QTc prolongation as well as the possible interaction between polymorphisms and risk medications in determining QTc prolongation were investigated. Medications were classified according to their known risk of inducing QTc prolongation (high-to-moderate, low, and no risk). QTc duration and risk of QTc > median value were investigated in a sample of 77 patients with mood or psychotic disorders being treated with antidepressants and antipsychotics, and who had at least 1 ECG recording. A secondary analysis considered QTc percentage change in patients (n = 25) with 2 ECG recordings. Single-nucleotide polymorphisms previously associated with QTc prolongation during treatment with psychotropic medications were investigated. No association survived after multiple-testing correction. The best results for modulation of QTc duration were identified for rs10808071 (the ABCB1 gene, nominal p = 0.007) when at least 1 medication with a moderate-to-high risk was prescribed, and for rs12029454 (the NOS1AP gene) in patients taking at least 1 medication with a cardiovascular risk (nominal p = 0.008). In the secondary analysis, rs2072413 (the KCNH2 gene) was the top finding for the modulation of QTc percentage change (nominal p = 0.001) when 1 drug with a moderate-to-high risk was added compared to baseline. Despite the limited power of this study, our results suggest that ABCB1, NOS1AP, and KCNH2 may play a role in QTc duration/prolongation during treatment with psychotropic drugs.

Alzheimer's Disease and Neurotransmission Gene Variants: Focus on Their Effects on Psychiatric Comorbidities and Inflammatory Parameters.

BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disorder accounting for 60-70% of dementia cases. Genetic origin accounts for 49-79% of disease risk. This paper aims to investigate the association of 17 polymorphisms within 7 genes involved in neurotransmission (COMT, HTR2A, PPP3CC, RORA, SIGMAR1, SIRT1, and SORBS3) and AD. METHODS: A Greek and an Italian sample were investigated, for a total of 156 AD subjects and 301 healthy controls. Exploratory analyses on psychosis and depression comorbidities were performed, as well as on other available clinical and serological parameters. RESULTS: AD was associated with rs4680 within the COMT gene in the total sample. Trends of association were found in the 2 subsamples. Some nominal associations were found for the depressive phenotype. rs10997871 and rs10997875 within SIRT1 were nominally associated with depression in the total sample and in the Greek subsample. rs174696 within COMT was associated with depression comorbidity in the Italian subsample. DISCUSSION: Our data support the role of COMT, and particularly of rs4680, in the pathogenesis of AD. Furthermore, the SIRT1 gene seems to modulate depressive symptomatology in the AD population.

Alpha-synuclein oligomers impair memory through glial cell activation and via Toll-like receptor 2.

Alpha-synuclein oligomers (α-synOs) are emerging as crucial factors in the pathogenesis of synucleinopathies. Although the connection between neuroinflammation and α-syn still remains elusive, increasing evidence suggests that extracellular moieties activate glial cells leading to neuronal damage. Using an acute mouse model, we explored whether α-synOs induce memory impairment in association to neuroinflammation, addressing Toll-like receptors 2 and 4 (TLR2 and TLR4) involvement. We found that α-synOs abolished mouse memory establishment in association to hippocampal glial activation. On brain slices α-synOs inhibited long-term potentiation. Indomethacin and Ibuprofen prevented the α-synOs-mediated detrimental actions. Furthermore, while the TLR2 functional inhibitor antibody prevented the memory deficit, oligomers induced memory deficits in the TLR4 knockout mice. In conclusion, solely α-synOs induce memory impairment likely inhibiting synaptic plasticity. α-synOs lead to hippocampal gliosis that is involved in memory impairment. Moreover, while the oligomer-mediated detrimental actions are TLR2 dependent, the involvement of TLR4 was ruled out.

Recombinant human Tat-Hsp70-2: A tool for neuroprotection.

Human Hsp70-2 is a chaperone expressed mainly in the nervous system. Up to now, no study has reported on the recombinant expression of this important human chaperone. Herein, we describe the successful purification and characterization of recombinant human Hsp70-2 in Escherichia coli in both the full-length and the chimeric protein containing the protein transduction domain corresponding to the trans-activator of transcription (Tat) from HIV. Under optimized conditions, the Tat-Hsp70-2 was expressed in a soluble form and purified by two chromatographic steps (in a 3.6 mg/L fermentation broth yield): recombinant Tat-Hsp70-2 was folded and showed ATPase activity. In contrast, the full-length recombinant protein was only expressed in the form of inclusion bodies and thus was purified following a refolding procedure. The refolded Hsp70-2 protein was inactive and the protein conformation slightly altered as compared to the corresponding Tat-fused variant. The Tat-Hsp70-2 protein (100 nM), when added to human neuroblastoma SH-SY5Y cells subjected to hydrogen peroxide or 6-hydroxydopamine stress, partially protected from the deleterious effect of these treatments. This work describes an approach for the functional expression of human Tat-Hsp70-2 that provides sufficient material for detailed structure-function studies and for testing its ability to protect neuroblastoma cells from oxidative stress.

Neuroplasticity and second messenger pathways in antidepressant efficacy: pharmacogenetic results from a prospective trial investigating treatment resistance.

Genes belonging to neuroplasticity, monoamine, circadian rhythm, and transcription factor pathways were investigated as modulators of antidepressant efficacy. The present study aimed (1) to replicate previous findings in an independent sample with treatment-resistant depression (TRD), and (2) to perform a pathway analysis to investigate the possible molecular mechanisms involved. 220 patients with major depressive disorder who were non-responders to a previous antidepressant were treated with venlafaxine for 4-6 weeks and in case of non-response with escitalopram for 4-6 weeks. Symptoms were assessed using the Montgomery Asberg Depression Rating Scale. The phenotypes were response and remission to venlafaxine, non-response (TRDA) and non-remission (TRDB) to neither venlafaxine nor escitalopram. 50 tag SNPs in 14 genes belonging to the pathways of interest were tested for association with phenotypes. Molecular pathways (KEGG database) that included one or more of the genes associated with the phenotypes were investigated also in the STAR*D sample. The associations between ZNF804A rs7603001 and response, CREB1 rs2254137 and remission were replicated, as well as CHL1 rs2133402 and lower risk of TRD. Other CHL1 SNPs were potential predictors of TRD (rs1516340, rs2272522, rs1516338, rs2133402). The MAPK1 rs6928 SNP was consistently associated with all the phenotypes. The protein processing in endoplasmic reticulum pathway (hsa04141) was the best pathway that may explain the mechanisms of MAPK1 involvement in antidepressant response. Signals in genes previously associated with antidepressant efficacy were confirmed for CREB1, ZNF804A and CHL1. These genes play pivotal roles in synaptic plasticity, neural activity and connectivity.

Association between Sirtuin 1 Gene rs10997870 Polymorphism and Suicide Behaviors in Bipolar Disorder.

BACKGROUND/AIMS: Suicidal behavior (SB) in bipolar disorder (BD) is a complex multifactorial event resulting from an interaction of genetic, neurobiological and psychosocial factors. Recent studies identified new possible mechanisms, suggesting a role for sirtuins (SIRTs 1-7), a family of nicotinamide adenine dinucleotide-dependent enzymes with a multifaceted role in the central nervous system. The aims of the present study were: (1) to investigate the effects of the rs10997870 SIRT1 gene variant on SB in BD; (2) to explore the effects of the same gene variant on specific depressive symptoms at the severest episode. METHODS: One hundred and eighty DSM-IV bipolar outpatients were enrolled in a naturalistic cohort study. The rs10997870 polymorphism within the SIRT1 gene was analyzed. RESULTS: An association between the GG genotype and SB was detected (lifetime: p = 0.015). Compared to other genotypes, GG carriers presented more frequently psychomotor agitation (p = 0.009) and a higher Hamilton Depression Rating Scale total score (p = 0.014) at the severest depressive episode. SB and psychomotor agitation were found to be associated with GG carriers and G allele in a multivariate analysis as well. CONCLUSION: Our findings suggest a role of the rs10997870 SIRT1 gene variant in SB amongst BD patients and its association with specific depressive symptoms. Despite a number of limitations of this exploratory study, our results may provide new insight into the mechanisms underlying SB in BD.

Clinical and genetic factors associated with suicide in mood disorder patients.

Suicidality is a continuum ranging from ideation to attempted and completed suicide, with a complex etiology involving both genetic heritability and environmental factors. The majority of suicide events occur in the context of psychiatric conditions, preeminently major depression and bipolar disorder. The present study investigates clinical factors associated with suicide in a sample of 553 mood disorder patients, recruited within the 'Psy Pluriel' center, Centre Européen de Psychologie Médicale, and the Department of Psychiatry of Erasme Hospital (Brussels). Furthermore, genetic association analyses examining polymorphisms within COMT, BDNF, MAPK1 and CREB1 genes were performed in a subsample of 259 bipolar patients. The presence or absence of a previous suicide attempt and of current suicide risk were assessed. A positive association with suicide attempt was reported for younger patients, females, lower educated, smokers, those with higher scores on depressive symptoms and higher functional disability and those with anxiety comorbidity and familial history of suicidality in first- and second-degree relatives. Anxiety disorder comorbidity was the stronger predictor of current suicide risk. No associations were found with polymorphisms within COMT and BDNF genes, whereas significant associations were found with variations in rs13515 (MAPK1) and rs6740584 (CREB1) polymorphisms. From a clinical perspective, our study proposes several clinical characteristics, such as increased depressive symptomatology, anxiety comorbidity, functional disability and family history of suicidality, as correlates associated with suicide. Genetic risk variants in MAPK1 and CREB1 genes might be involved in a dysregulation of inflammatory and neuroplasticity pathways and are worthy of future investigation.

Genetics of psychotropic medication induced side effects in two independent samples of bipolar patients.

The treatment of bipolar disorder (BD) usually requires combination therapies, with the critical issue of the emergence of adverse drug reactions (ADRs) and the possibility of low treatment adherence. Genetic polymorphisms are hypothesized to modulate the pharmacodynamics of psychotropic drugs, representing potential biological markers of ADRs. This study investigated genes involved in the regulation of neuroplasticity (BDNF, ST8SIA2), second messenger cascades (GSK3B, MAPK1, and CREB1), circadian rhythms (RORA), transcription (SP4, ZNF804A), and monoaminergic system (HTR2A and COMT) in the risk of neurological, psychic, autonomic, and other ADRs. Two independent samples of BD patients naturalistically treated were included (COPE-BD n = 147; STEP-BD n = 659). In the COPE-BD 34 SNPs were genotyped, while in the STEP-BD polymorphisms in the selected genes were extracted from the genome-wide dataset. Each ADRs group was categorized as absent-mild or moderate-severe and logistic regression with appropriate covariates was applied to identify possible risk genotypes/alleles. 58.5 and 93.5 % of patients were treated with mood stabilizers, 44.2 and 50.7 % were treated with antipsychotics, and 69.4 and 46.1 % were treated with antidepressants in the COPE-BD and STEP-BD, respectively. Our findings suggested that ST8SIA2 may be associated with psychic ADRs, as shown in the COPE-BD (rs4777989 p = 0.0017) and STEP-BD (rs56027313, rs13379489 and rs10852173). A cluster of RORA SNPs around rs2083074 showed an effect on psychic ADRs in the STEP-BD. Trends supporting the association between HTR2A and autonomic ADRs were found in both samples. Confirmations are needed particularly for ST8SIA2 and RORA since the few available data regarding their role in relation to psychotropic ADRs.

Cross-linked poly(acrylic acids) microgels and agarose as semi-interpenetrating networks for resveratrol release.

Carbomers, cross-linked poly(acrylic acid) microgels, have been widely used in pharmaceutical formulations as swollen hydrogels. Agarose, whose thermoreversibility may be exploited for drug loading, forms a gel with a mechanism involving coil-helix transition at about 36 °C. In this work carbomer microgels were combined with agarose networks in a semi-interpenetrating polymer network structure, aiming at obtaining suitable delivery systems for the loading and release of molecules with poor bioavailability but high therapeutic interest, like resveratrol. The rheological properties of the formulations and their in vitro cytocompatibility were studied and optimized acting on the neutralizing agent (triethylamine (N,N-diethylethanamine), triethanolamine (tris(2-hydroxyethyl)amine) and sodium hydroxide) and amount of OH donors (1,2-propanediol and glycerol). As a preparation method, autoclaving was introduced to simultaneously obtain heating and sterilising. Among the different neutralizing agents, NaOH was chosen to avoid the use of amines, considering the final application. Without the addition of alcohols as typical OH donors to induce Carbomer gelification, gels with appropriate rheological properties and stability were produced. For this formulation, the release of resveratrol after 7 days was about 80 % of the loaded mass, suggesting it is an interesting approach to be exploited for the development of innovative resveratrol delivery systems.

The Parkinson's disease-related protein DJ-1 protects dopaminergic neurons in vivo and cultured cells from alpha-synuclein and 6-hydroxydopamine toxicity.

BACKGROUND: Dopaminergic degeneration is a major finding in brains of patients with Parkinson's disease (PD), together with Lewy bodies, intraneuronal inclusions mainly composed of the fibrillogenic protein α-synuclein (α-syn). The familial-PD-related protein DJ-1 was reported to reduce dopaminergic degeneration triggered by α-syn or by the dopaminergic-selective neurotoxin 6-hydroxydopamine (6-OHDA). OBJECTIVE: The aim was to further investigate the role of DJ-1 in dopaminergic degeneration and to see whether a cell-permeable recombinant form of DJ-1 (TAT-DJ-1) could restore dopamine depletion in vivo, thus representing an innovative therapeutic approach. METHODS: We developed in vitro (PC12/TetOn cells and mouse primary mesencephalic neurons) and in vivo models [including DJ-1 knockout (-/-) mice] to investigate DJ-1 in dopaminergic degeneration. RESULTS: We found that in PC12/TetOn cells overexpressing α-syn with the familial-PD linked mutation A30P, DJ-1 silencing increased α-syn (A30P) toxicity. Primary mesencephalic neurons from DJ-1 (-/-) mice were more vulnerable to a cell-permeable form of α-syn (TAT-α-syn) and to 6-OHDA. Intrastriatally administered TAT-DJ-1 reduced 6-OHDA toxicity in vivo in C57BL/6 mice. Finally, when we injected TAT-α-syn (A30P) in the striatum of DJ-1 (-/-) animals, dopamine was depleted more than in the control strain. CONCLUSION: DJ-1 appears to have a protective role against dopaminergic degeneration triggered by α-syn or 6-OHDA, reinforcing the possible therapeutic importance of this protein in PD.