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1.
Nature ; 615(7952): 490-498, 2023 03.
Article in English | MEDLINE | ID: mdl-36890227

ABSTRACT

Metabolic rewiring underlies the effector functions of macrophages1-3, but the mechanisms involved remain incompletely defined. Here, using unbiased metabolomics and stable isotope-assisted tracing, we show that an inflammatory aspartate-argininosuccinate shunt is induced following lipopolysaccharide stimulation. The shunt, supported by increased argininosuccinate synthase (ASS1) expression, also leads to increased cytosolic fumarate levels and fumarate-mediated protein succination. Pharmacological inhibition and genetic ablation of the tricarboxylic acid cycle enzyme fumarate hydratase (FH) further increases intracellular fumarate levels. Mitochondrial respiration is also suppressed and mitochondrial membrane potential increased. RNA sequencing and proteomics analyses demonstrate that there are strong inflammatory effects resulting from FH inhibition. Notably, acute FH inhibition suppresses interleukin-10 expression, which leads to increased tumour necrosis factor secretion, an effect recapitulated by fumarate esters. Moreover, FH inhibition, but not fumarate esters, increases interferon-ß production through mechanisms that are driven by mitochondrial RNA (mtRNA) release and activation of the RNA sensors TLR7, RIG-I and MDA5. This effect is recapitulated endogenously when FH is suppressed following prolonged lipopolysaccharide stimulation. Furthermore, cells from patients with systemic lupus erythematosus also exhibit FH suppression, which indicates a potential pathogenic role for this process in human disease. We therefore identify a protective role for FH in maintaining appropriate macrophage cytokine and interferon responses.


Subject(s)
Fumarate Hydratase , Interferon-beta , Macrophages , Mitochondria , RNA, Mitochondrial , Humans , Argininosuccinate Synthase/metabolism , Argininosuccinic Acid/metabolism , Aspartic Acid/metabolism , Cell Respiration , Cytosol/metabolism , Fumarate Hydratase/antagonists & inhibitors , Fumarate Hydratase/genetics , Fumarate Hydratase/metabolism , Fumarates/metabolism , Interferon-beta/biosynthesis , Interferon-beta/immunology , Lipopolysaccharides/pharmacology , Lipopolysaccharides/metabolism , Lupus Erythematosus, Systemic/enzymology , Macrophages/enzymology , Macrophages/immunology , Macrophages/metabolism , Membrane Potential, Mitochondrial , Metabolomics , Mitochondria/genetics , Mitochondria/metabolism , RNA, Mitochondrial/metabolism
2.
Eur J Immunol ; 52(7): 1024-1034, 2022 07.
Article in English | MEDLINE | ID: mdl-35569038

ABSTRACT

Activation of the coagulation cascade is a critical, evolutionarily conserved mechanism that maintains hemostasis by rapidly forming blood clots in response to blood-borne infections and damaged blood vessels. Coagulation is a key component of innate immunity since it prevents bacterial dissemination and can provoke inflammation. The term immunothrombosis describes the process by which the innate immune response drives aberrant coagulation, which can result in a lethal condition termed disseminated intravascular coagulation, often seen in sepsis. In this review, we describe the recently uncovered molecular mechanisms underlying inflammasome- and STING-driven immunothrombosis induced by bacterial and viral infections, culminating in tissue factor (TF) activation and release. Current anticoagulant therapeutics, while effective, are associated with a life-threatening bleeding risk, requiring the urgent development of new treatments. Targeting immunothrombosis may provide a safer option. Thus, we highlight preclinical tools which target TF and/or block canonical (NLRP3) or noncanonical (caspase-11) inflammasome activation as well as STING-driven TF release and discuss clinically approved drugs which block key immunothrombotic processes and, therefore, may be redeployed as safer anticoagulants.


Subject(s)
Inflammasomes , Thromboinflammation , Blood Coagulation , Hemostasis , Humans , Immunity, Innate
3.
Biochem J ; 479(6): 731-750, 2022 03 31.
Article in English | MEDLINE | ID: mdl-35344028

ABSTRACT

The interplay between innate immunity and coagulation after infection or injury, termed immunothrombosis, is the primary cause of disseminated intravascular coagulation (DIC), a condition that occurs in sepsis. Thrombosis associated with DIC is the leading cause of death worldwide. Interest in immunothrombosis has grown because of COVID-19, the respiratory disease caused by SARS-CoV-2, which has been termed a syndrome of dysregulated immunothrombosis. As the relatively new field of immunothrombosis expands at a rapid pace, the focus of academic and pharmacological research has shifted from generating treatments targeted at the traditional 'waterfall' model of coagulation to therapies better directed towards immune components that drive coagulopathies. Immunothrombosis can be initiated in macrophages by cleavage of the non-canonical inflammasome which contains caspase-11. This leads to release of tissue factor (TF), a membrane glycoprotein receptor that forms a high-affinity complex with coagulation factor VII/VIIa to proteolytically activate factors IX to IXa and X to Xa, generating thrombin and leading to fibrin formation and platelet activation. The mechanism involves the post-translational activation of TF, termed decryption, and release of decrypted TF via caspase-11-mediated pyroptosis. During aberrant immunothrombosis, decryption of TF leads to thromboinflammation, sepsis, and DIC. Therefore, developing therapies to target pyroptosis have emerged as an attractive concept to counteract dysregulated immunothrombosis. In this review, we detail the three mechanisms of TF control: concurrent induction of TF, caspase-11, and NLRP3 (signal 1); TF decryption, which increases its procoagulant activity (signal 2); and accelerated release of TF into the intravascular space via pyroptosis (signal 3). In this way, decryption of TF is analogous to the two signals of NLRP3 inflammasome activation, whereby induction of pro-IL-1ß and NLRP3 (signal 1) is followed by activation of NLRP3 (signal 2). We describe in detail TF decryption, which involves pathogen-induced alterations in the composition of the plasma membrane and modification of key cysteines on TF, particularly at the location of the critical, allosterically regulated disulfide bond of TF in its 219-residue extracellular domain. In addition, we speculate towards the importance of identifying new therapeutics to block immunothrombotic triggering of TF, which can involve inhibition of pyroptosis to limit TF release, or the direct targeting of TF decryption using cysteine-modifying therapeutics.


Subject(s)
COVID-19 Drug Treatment , Thrombosis , Anticoagulants/pharmacology , Anticoagulants/therapeutic use , Humans , Inflammation/complications , Pyroptosis , SARS-CoV-2 , Thromboinflammation , Thromboplastin/metabolism
4.
Hum Brain Mapp ; 43(1): 56-82, 2022 01.
Article in English | MEDLINE | ID: mdl-32725849

ABSTRACT

MRI-derived brain measures offer a link between genes, the environment and behavior and have been widely studied in bipolar disorder (BD). However, many neuroimaging studies of BD have been underpowered, leading to varied results and uncertainty regarding effects. The Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Bipolar Disorder Working Group was formed in 2012 to empower discoveries, generate consensus findings and inform future hypothesis-driven studies of BD. Through this effort, over 150 researchers from 20 countries and 55 institutions pool data and resources to produce the largest neuroimaging studies of BD ever conducted. The ENIGMA Bipolar Disorder Working Group applies standardized processing and analysis techniques to empower large-scale meta- and mega-analyses of multimodal brain MRI and improve the replicability of studies relating brain variation to clinical and genetic data. Initial BD Working Group studies reveal widespread patterns of lower cortical thickness, subcortical volume and disrupted white matter integrity associated with BD. Findings also include mapping brain alterations of common medications like lithium, symptom patterns and clinical risk profiles and have provided further insights into the pathophysiological mechanisms of BD. Here we discuss key findings from the BD working group, its ongoing projects and future directions for large-scale, collaborative studies of mental illness.


Subject(s)
Bipolar Disorder , Cerebral Cortex , Magnetic Resonance Imaging , Neuroimaging , Bipolar Disorder/diagnostic imaging , Bipolar Disorder/pathology , Cerebral Cortex/diagnostic imaging , Cerebral Cortex/pathology , Humans , Meta-Analysis as Topic , Multicenter Studies as Topic
5.
Alcohol Clin Exp Res ; 46(5): 749-758, 2022 05.
Article in English | MEDLINE | ID: mdl-35307836

ABSTRACT

BACKGROUND: Impaired decision making, a key characteristic of alcohol dependence (AD), manifests in continuous alcohol consumption despite severe negative consequences. The neural basis of this impairment in individuals with AD and differences with known neural decision mechanisms among healthy subjects are not fully understood. In particular, it is unclear whether the choice behavior among individuals with AD is based on a general impairment of decision mechanisms or is mainly explained by altered value attribution, with an overly high subjective value attributed to alcohol-related stimuli. METHODS: Here, we use a functional magnetic resonance imaging (fMRI) monetary reward task to compare the neural processes of model-based decision making and value computation between AD individuals (n = 32) and healthy controls (n = 32). During fMRI, participants evaluated monetary offers with respect to dynamically changing constraints and different levels of uncertainty. RESULTS: Individuals with AD showed lower activation associated with model-based decision processes in the caudate nucleus than controls, but there were no group differences in value-related neural activity or task performance. CONCLUSIONS: Our findings highlight the role of the caudate nucleus in impaired model-based decisions of alcohol-dependent individuals.


Subject(s)
Alcoholism , Caudate Nucleus , Alcoholism/diagnostic imaging , Caudate Nucleus/diagnostic imaging , Decision Making/physiology , Humans , Magnetic Resonance Imaging/methods , Reward
6.
Hum Brain Mapp ; 42(10): 3269-3281, 2021 07.
Article in English | MEDLINE | ID: mdl-33818852

ABSTRACT

Extensive research has demonstrated that rs1360780, a common single nucleotide polymorphism within the FKBP5 gene, interacts with early-life stress in predicting psychopathology. Previous results suggest that carriers of the TT genotype of rs1360780 who were exposed to child abuse show differences in structure and functional activation of emotion-processing brain areas belonging to the salience network. Extending these findings on intermediate phenotypes of psychopathology, we examined if the interaction between rs1360780 and child abuse predicts resting-state functional connectivity (rsFC) between the amygdala and other areas of the salience network. We analyzed data of young European adults from the general population (N = 774; mean age = 18.76 years) who took part in the IMAGEN study. In the absence of main effects of genotype and abuse, a significant interaction effect was observed for rsFC between the right centromedial amygdala and right posterior insula (p < .025, FWE-corrected), which was driven by stronger rsFC in TT allele carriers with a history of abuse. Our results suggest that the TT genotype of rs1360780 may render individuals with a history of abuse more vulnerable to functional changes in communication between brain areas processing emotions and bodily sensations, which could underlie or increase the risk for psychopathology.


Subject(s)
Adult Survivors of Child Abuse , Adverse Childhood Experiences , Amygdala/physiology , Connectome , Tacrolimus Binding Proteins/genetics , Adolescent , Adult , Amygdala/diagnostic imaging , Female , Gene-Environment Interaction , Humans , Magnetic Resonance Imaging , Male , Polymorphism, Single Nucleotide , Young Adult
7.
Mol Psychiatry ; 25(7): 1511-1525, 2020 07.
Article in English | MEDLINE | ID: mdl-31471575

ABSTRACT

Alterations in white matter (WM) microstructure have been implicated in the pathophysiology of major depressive disorder (MDD). However, previous findings have been inconsistent, partially due to low statistical power and the heterogeneity of depression. In the largest multi-site study to date, we examined WM anisotropy and diffusivity in 1305 MDD patients and 1602 healthy controls (age range 12-88 years) from 20 samples worldwide, which included both adults and adolescents, within the MDD Working Group of the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) consortium. Processing of diffusion tensor imaging (DTI) data and statistical analyses were harmonized across sites and effects were meta-analyzed across studies. We observed subtle, but widespread, lower fractional anisotropy (FA) in adult MDD patients compared with controls in 16 out of 25 WM tracts of interest (Cohen's d between 0.12 and 0.26). The largest differences were observed in the corpus callosum and corona radiata. Widespread higher radial diffusivity (RD) was also observed (all Cohen's d between 0.12 and 0.18). Findings appeared to be driven by patients with recurrent MDD and an adult age of onset of depression. White matter microstructural differences in a smaller sample of adolescent MDD patients and controls did not survive correction for multiple testing. In this coordinated and harmonized multisite DTI study, we showed subtle, but widespread differences in WM microstructure in adult MDD, which may suggest structural disconnectivity in MDD.


Subject(s)
Depressive Disorder, Major/pathology , White Matter/pathology , Adult , Aged , Aged, 80 and over , Anisotropy , Cohort Studies , Corpus Callosum/diagnostic imaging , Corpus Callosum/pathology , Depressive Disorder, Major/diagnostic imaging , Diffusion Tensor Imaging , Female , Humans , Male , Middle Aged , White Matter/diagnostic imaging , Young Adult
8.
Cereb Cortex ; 30(4): 2707-2718, 2020 04 14.
Article in English | MEDLINE | ID: mdl-31828294

ABSTRACT

Recent large-scale, genome-wide association studies (GWAS) have identified hundreds of genetic loci associated with general intelligence. The cumulative influence of these loci on brain structure is unknown. We examined if cortical morphology mediates the relationship between GWAS-derived polygenic scores for intelligence (PSi) and g-factor. Using the effect sizes from one of the largest GWAS meta-analysis on general intelligence to date, PSi were calculated among 10 P value thresholds. PSi were assessed for the association with g-factor performance, cortical thickness (CT), and surface area (SA) in two large imaging-genetics samples (IMAGEN N = 1651; IntegraMooDS N = 742). PSi explained up to 5.1% of the variance of g-factor in IMAGEN (F1,1640 = 12.2-94.3; P < 0.005), and up to 3.0% in IntegraMooDS (F1,725 = 10.0-21.0; P < 0.005). The association between polygenic scores and g-factor was partially mediated by SA and CT in prefrontal, anterior cingulate, insula, and medial temporal cortices in both samples (PFWER-corrected < 0.005). The variance explained by mediation was up to 0.75% in IMAGEN and 0.77% in IntegraMooDS. Our results provide evidence that cumulative genetic load influences g-factor via cortical structure. The consistency of our results across samples suggests that cortex morphology could be a novel potential biomarker for neurocognitive dysfunction that is among the most intractable psychiatric symptoms.


Subject(s)
Cerebral Cortex/diagnostic imaging , Cerebral Cortex/physiology , Genome-Wide Association Study/methods , Intelligence/physiology , Multifactorial Inheritance/physiology , Adolescent , Female , Humans , Longitudinal Studies , Male
9.
Psychol Med ; 50(16): 2740-2750, 2020 12.
Article in English | MEDLINE | ID: mdl-31637983

ABSTRACT

BACKGROUND: Limbic-cortical imbalance is an established model for the neurobiology of major depressive disorder (MDD), but imaging genetics studies have been contradicting regarding potential risk and resilience mechanisms. Here, we re-assessed previously reported limbic-cortical alterations between MDD relatives and controls in combination with a newly acquired sample of MDD patients and controls, to disentangle pathology, risk, and resilience. METHODS: We analyzed functional magnetic resonance imaging data and negative affectivity (NA) of MDD patients (n = 48), unaffected first-degree relatives of MDD patients (n = 49) and controls (n = 109) who performed a faces matching task. Brain response and task-dependent amygdala functional connectivity (FC) were compared between groups and assessed for associations with NA. RESULTS: Groups did not differ in task-related brain activation but activation in the superior frontal gyrus (SFG) was inversely correlated with NA in patients and controls. Pathology was associated with task-independent decreases of amygdala FC with regions of the default mode network (DMN) and decreased amygdala FC with the medial frontal gyrus during faces matching, potentially reflecting a task-independent DMN predominance and a limbic-cortical disintegration during faces processing in MDD. Risk was associated with task-independent decreases of amygdala-FC with fronto-parietal regions and reduced faces-associated amygdala-fusiform gyrus FC. Resilience corresponded to task-independent increases in amygdala FC with the perigenual anterior cingulate cortex (pgACC) and increased FC between amygdala, pgACC, and SFG during faces matching. CONCLUSION: Our results encourage a refinement of the limbic-cortical imbalance model of depression. The validity of proposed risk and resilience markers needs to be tested in prospective studies. Further limitations are discussed.


Subject(s)
Amygdala/physiopathology , Depressive Disorder, Major/physiopathology , Depressive Disorder, Major/psychology , Emotions/physiology , Resilience, Psychological , Adult , Biomarkers , Brain Mapping , Female , Humans , Magnetic Resonance Imaging , Male , Risk Factors , Young Adult
10.
BJOG ; 125(9): 1171-1177, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29336101

ABSTRACT

OBJECTIVE: To compare the recurrence rates after complete response to topical treatment with either cidofovir or imiquimod for vulval intraepithelial neoplasia (VIN) 3. DESIGN: A prospective, open, randomised multicentre trial. SETTING: 32 general hospitals located in Wales and England. POPULATION OR SAMPLE: 180 patients were randomised consecutively between 21 October 2009 and 11 January 2013, 89 to cidofoovir (of whom 41 completely responded to treatment) and 91 to imiquimod (of whom 42 completely responded to treatment). METHODS: After 24 weeks of treatment, complete responders were followed up at 6-monthly intervals for 24 months. At each visit, the Common Terminology Criteria for Adverse Events (CTCAE) v3.0 was assessed and any new lesions were biopsied for histology. MAIN OUTCOME MEASURES: Time to histologically confirmed disease recurrence (any grade of VIN). RESULTS: The median length of follow up was 18.4 months. At 18 months, more participants were VIN-free in the cidofovir arm: 94% (95% CI 78.2-98.5) versus 71.6% (95% CI 52.0-84.3) [univariable hazard ratio (HR) 3.46, 95% CI 0.95-12.60, P = 0.059; multivariable HR 3.53, 95% CI 0.96-12.98, P = 0.057). The number of grade 2+ events was similar between treatment arms (imiquimod: 24/42 (57%) versus cidofovir: 27/41 (66%), χ2 = 0.665, P = 0.415), with no grade 4+. CONCLUSIONS: Long-term data indicates a trend towards response being maintained for longer following treatment with cidofovir than with imiquimod, with similar low rates of adverse events for each drug. Adverse event rates indicated acceptable safety of both drugs TWEETABLE ABSTRACT: Long-term follow up in the RT3VIN trial suggests cidofovir may maintain response for longer than imiquimod.


Subject(s)
Antineoplastic Agents/administration & dosage , Carcinoma in Situ/drug therapy , Cidofovir/administration & dosage , Imiquimod/administration & dosage , Neoplasm Recurrence, Local/epidemiology , Vulvar Neoplasms/drug therapy , Administration, Topical , Antineoplastic Agents/adverse effects , Carcinoma in Situ/epidemiology , Carcinoma in Situ/pathology , Cidofovir/adverse effects , Female , Humans , Imiquimod/adverse effects , Middle Aged , Neoplasm Recurrence, Local/etiology , Neoplasm Recurrence, Local/pathology , Prospective Studies , Treatment Outcome , Vulvar Neoplasms/epidemiology , Vulvar Neoplasms/pathology
11.
Int J Biometeorol ; 62(5): 843-850, 2018 May.
Article in English | MEDLINE | ID: mdl-29204686

ABSTRACT

The specific impact of weather factors on psychiatric disorders has been investigated only in few studies with inconsistent results. We hypothesized that meteorological conditions influence the number of cases presenting in a psychiatric emergency room as a measure of mental health conditions. We analyzed the number of patients consulting the emergency room (ER) of a psychiatric hospital in Berlin, Germany, between January 1, 2008, and December 31, 2014. A total of N = 22,672 cases were treated in the ER over the study period. Meteorological data were obtained from a publicly available data base. Due to collinearity among the meteorological variables, we performed a principal component (PC) analysis. Association of PCs with the daily number of patients was analyzed with autoregressive integrated moving average model. Delayed effects were investigated using Granger causal modeling. Daily number of patients in the ER was significantly higher in spring and summer compared to fall and winter (p < 0.001). Three PCs explained 76.8% percent of the variance with PC1 loading mostly on temperature, PC2 on cloudiness and low pressure, and PC3 on windiness. PC1 and PC2 showed strong association with number of patients in the emergency room (p < 0.010) indicating higher patient numbers on warmer and on cloudy days. Further, PC1, PC2, and PC3 predicted the number of patients presenting in the emergency room for up to 7 days (p < 0.050). A secondary analysis revealed that the effect of temperature on number of patients was mostly due to lower patient numbers on cold days. Although replication of our findings is required, our results suggest that weather influences the number of psychiatric patients consulting the emergency room. In particular, our data indicate lower patient numbers during very cold temperatures.


Subject(s)
Emergency Service, Hospital/statistics & numerical data , Hospitals, Psychiatric/statistics & numerical data , Mental Disorders/epidemiology , Weather , Berlin/epidemiology , Humans
12.
Hum Brain Mapp ; 38(6): 2795-2807, 2017 06.
Article in English | MEDLINE | ID: mdl-28317230

ABSTRACT

Threshold-free cluster enhancement (TFCE) is a sensitive means to incorporate spatial neighborhood information in neuroimaging studies without using arbitrary thresholds. The majority of methods have applied TFCE to voxelwise data. The need to understand the relationship among multiple variables and imaging modalities has become critical. We propose a new method of applying TFCE to vertexwise statistical images as well as cortexwise (either voxel- or vertexwise) mediation analysis. Here we present TFCE_mediation, a toolbox that can be used for cortexwise multiple regression analysis with TFCE, and additionally cortexwise mediation using TFCE. The toolbox is open source and publicly available (https://github.com/trislett/TFCE_mediation). We validated TFCE_mediation in healthy controls from two independent multimodal neuroimaging samples (N = 199 and N = 183). We found a consistent structure-function relationship between surface area and the first independent component (IC1) of the N-back task, that white matter fractional anisotropy is strongly associated with IC1 N-back, and that our voxel-based results are essentially identical to FSL randomise using TFCE (all PFWE <0.05). Using cortexwise mediation, we showed that the relationship between white matter FA and IC1 N-back is mediated by surface area in the right superior frontal cortex (PFWE  < 0.05). We also demonstrated that the same mediation model is present using vertexwise mediation (PFWE  < 0.05). In conclusion, cortexwise analysis with TFCE provides an effective analysis of multimodal neuroimaging data. Furthermore, cortexwise mediation analysis may identify or explain a mechanism that underlies an observed relationship among a predictor, intermediary, and dependent variables in which one of these variables is assessed at a whole-brain scale. Hum Brain Mapp 38:2795-2807, 2017. © 2017 Wiley Periodicals, Inc.


Subject(s)
Brain Mapping/methods , Cerebral Cortex/diagnostic imaging , Image Interpretation, Computer-Assisted , Adult , Computer Simulation , Female , Humans , Male , Middle Aged , Multimodal Imaging , Regression Analysis , Reproducibility of Results , White Matter/diagnostic imaging
13.
Hum Psychopharmacol ; 32(1)2017 01.
Article in English | MEDLINE | ID: mdl-28120489

ABSTRACT

OBJECTIVE: Tardive dyskinesia (TD) is a motor side effect that may develop after long-term antipsychotic treatment. Schizophrenia has recently been associated with the Neurexin-1 (NRXN1) gene that codes for a cell adhesion molecule in synaptic communication. METHODS: This study examined five NRXN1 single-nucleotide polymorphisms (SNPs) for possible association with the occurrence and severity of TD in 178 schizophrenia patients of European ancestry. RESULTS: We did not find these SNPs to be significantly associated with TD. CONCLUSIONS: More research is needed with additional SNPs and in bigger samples before we can completely rule out the role of NRXN1 in TD.


Subject(s)
Antipsychotic Agents/adverse effects , Cell Adhesion Molecules, Neuronal/genetics , Genetic Association Studies/methods , Nerve Tissue Proteins/genetics , Polymorphism, Single Nucleotide/genetics , Schizophrenia/genetics , Tardive Dyskinesia/genetics , Adult , Calcium-Binding Proteins , Female , Humans , Male , Neural Cell Adhesion Molecules , Schizophrenia/drug therapy , Tardive Dyskinesia/chemically induced , White People/genetics
15.
J Neurosci ; 34(18): 6367-76, 2014 Apr 30.
Article in English | MEDLINE | ID: mdl-24790207

ABSTRACT

The genetic and molecular pathways driving human brain white matter (WM) development are only beginning to be discovered. Long chain polyunsaturated fatty acids (LC-PUFAs) have been implicated in myelination in animal models and humans. The biosynthesis of LC-PUFAs is regulated by the fatty acid desaturase (FADS) genes, of which a human-specific haplotype is strongly associated with ω-3 and ω-6 LC-PUFA concentrations in blood. To investigate the relationship between LC-PUFA synthesis and human brain WM development, we examined whether this FADS haplotype is associated with age-related WM differences across the life span in healthy individuals 9-86 years of age (n = 207). Diffusion tensor imaging was performed to measure fractional anisotropy (FA), a putative measure of myelination, of the cerebral WM tracts. FADS haplotype status was determined with a single nucleotide polymorphism (rs174583) that tags this haplotype. Overall, normal age-related WM differences were observed, including higher FA values in early adulthood compared with childhood, followed by lower FA values across older age ranges. However, individuals homozygous for the minor allele (associated with lower LC-PUFA concentrations) did not display these normal age-related WM differences (significant age × genotype interactions, p(corrected) < 0.05). These findings suggest that LC-PUFAs are involved in human brain WM development from childhood into adulthood. This haplotype and LC-PUFAs may play a role in myelin-related disorders of neurodevelopmental origin.


Subject(s)
Brain/anatomy & histology , Fatty Acid Desaturases/genetics , Fatty Acids/metabolism , Nerve Fibers, Myelinated/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Anisotropy , Brain/blood supply , Brain/growth & development , Child , Female , Genotype , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Oxygen/blood , Polymorphism, Single Nucleotide/genetics , Young Adult
16.
J Neural Transm (Vienna) ; 122(1): 29-34, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25150845

ABSTRACT

Genetic variation in cytochrome enzymes is known to affect drug metabolism and influence treatment response. Recently, the rs472660 variant in CYP3A43 has been associated with olanzapine response and clearance. In this study, we investigated the impact of rs472660 and the putatively functional marker rs680055 on antipsychotic response. We genotyped the rs472660 and rs680055 single nucleotide polymorphisms (SNPs) in N = 152 schizophrenia patients of European descent collected at two sample sites who were predominately treated with second generation antipsychotics for up to 6 months. Treatment response was assessed prospectively using Brief Psychiatric Rating Scale (BPRS) scores. Statistical analysis was performed using Chi square and analysis of covariance. The rs680055 SNP was significantly associated with treatment response. Carriers of the minor allele had significantly lower BPRS scores at study end (p = 5.9 × 10(-4)) with 8 % of the variance being explained by rs680055 genotype. Post hoc analyses revealed that this effect was present in both samples and in both genders. The rs472660 SNP was also associated with response (p = 0.027); however, this finding was not significant after multiple test correction. This is the first evidence that the rs680055 missense mutation influences antipsychotic response. Although our finding for rs472660 was only a non-significant trend after correction, our results still support the notion that this SNP may play a role in antipsychotic response. Despite the fact that the functional role of CYP3A43 in antipsychotic metabolism is not fully understood yet, our study provides an important contribution to understanding genetic factors of antipsychotic response.


Subject(s)
Antipsychotic Agents/therapeutic use , Aryl Hydrocarbon Hydroxylases/genetics , Mental Disorders/drug therapy , Mental Disorders/genetics , Pharmacogenetics , Polymorphism, Single Nucleotide/genetics , Genotype , Humans , Psychiatric Status Rating Scales
17.
Neuroimage ; 101: 494-512, 2014 Nov 01.
Article in English | MEDLINE | ID: mdl-24784800

ABSTRACT

INTRODUCTION: Advances in image segmentation of magnetic resonance images (MRI) have demonstrated that multi-atlas approaches improve segmentation over regular atlas-based approaches. These approaches often rely on a large number of manually segmented atlases (e.g. 30-80) that take significant time and expertise to produce. We present an algorithm, MAGeT-Brain (Multiple Automatically Generated Templates), for the automatic segmentation of the hippocampus that minimises the number of atlases needed whilst still achieving similar agreement to multi-atlas approaches. Thus, our method acts as a reliable multi-atlas approach when using special or hard-to-define atlases that are laborious to construct. METHOD: MAGeT-Brain works by propagating atlas segmentations to a template library, formed from a subset of target images, via transformations estimated by nonlinear image registration. The resulting segmentations are then propagated to each target image and fused using a label fusion method. We conduct two separate Monte Carlo cross-validation experiments comparing MAGeT-Brain and basic multi-atlas whole hippocampal segmentation using differing atlas and template library sizes, and registration and label fusion methods. The first experiment is a 10-fold validation (per parameter setting) over 60 subjects taken from the Alzheimer's Disease Neuroimaging Database (ADNI), and the second is a five-fold validation over 81 subjects having had a first episode of psychosis. In both cases, automated segmentations are compared with manual segmentations following the Pruessner-protocol. Using the best settings found from these experiments, we segment 246 images of the ADNI1:Complete 1Yr 1.5 T dataset and compare these with segmentations from existing automated and semi-automated methods: FSL FIRST, FreeSurfer, MAPER, and SNT. Finally, we conduct a leave-one-out cross-validation of hippocampal subfield segmentation in standard 3T T1-weighted images, using five high-resolution manually segmented atlases (Winterburn et al., 2013). RESULTS: In the ADNI cross-validation, using 9 atlases MAGeT-Brain achieves a mean Dice's Similarity Coefficient (DSC) score of 0.869 with respect to manual whole hippocampus segmentations, and also exhibits significantly lower variability in DSC scores than multi-atlas segmentation. In the younger, psychosis dataset, MAGeT-Brain achieves a mean DSC score of 0.892 and produces volumes which agree with manual segmentation volumes better than those produced by the FreeSurfer and FSL FIRST methods (mean difference in volume: 80 mm(3), 1600 mm(3), and 800 mm(3), respectively). Similarly, in the ADNI1:Complete 1Yr 1.5 T dataset, MAGeT-Brain produces hippocampal segmentations well correlated (r>0.85) with SNT semi-automated reference volumes within disease categories, and shows a conservative bias and a mean difference in volume of 250 mm(3) across the entire dataset, compared with FreeSurfer and FSL FIRST which both overestimate volume differences by 2600 mm(3) and 2800 mm(3) on average, respectively. Finally, MAGeT-Brain segments the CA1, CA4/DG and subiculum subfields on standard 3T T1-weighted resolution images with DSC overlap scores of 0.56, 0.65, and 0.58, respectively, relative to manual segmentations. CONCLUSION: We demonstrate that MAGeT-Brain produces consistent whole hippocampal segmentations using only 9 atlases, or fewer, with various hippocampal definitions, disease populations, and image acquisition types. Additionally, we show that MAGeT-Brain identifies hippocampal subfields in standard 3T T1-weighted images with overlap scores comparable to competing methods.


Subject(s)
Hippocampus/anatomy & histology , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Adolescent , Adult , Aged , Aged, 80 and over , Aging/pathology , Alzheimer Disease/pathology , Atlases as Topic , Female , Hippocampus/pathology , Humans , Image Processing, Computer-Assisted/standards , Magnetic Resonance Imaging/standards , Male , Middle Aged , Monte Carlo Method , Psychotic Disorders/pathology , Young Adult
18.
medRxiv ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38766134

ABSTRACT

Current psychiatric diagnoses are not defined by neurobiological measures which hinders the development of therapies targeting mechanisms underlying mental illness 1,2 . Research confined to diagnostic boundaries yields heterogeneous biological results, whereas transdiagnostic studies often investigate individual symptoms in isolation. There is currently no paradigm available to comprehensively investigate the relationship between different clinical symptoms, individual disorders, and the underlying neurobiological mechanisms. Here, we propose a framework that groups clinical symptoms derived from ICD-10/DSM-V according to shared brain mechanisms defined by brain structure, function, and connectivity. The reassembly of existing ICD-10/DSM-5 symptoms reveal six cross-diagnostic psychopathology scores related to mania symptoms, depressive symptoms, anxiety symptoms, stress symptoms, eating pathology, and fear symptoms. They were consistently associated with multimodal neuroimaging components in the training sample of young adults aged 23, the independent test sample aged 23, participants aged 14 and 19 years, and in psychiatric patients. The identification of symptom groups of mental illness robustly defined by precisely characterized brain mechanisms enables the development of a psychiatric nosology based upon quantifiable neurobiological measures. As the identified symptom groups align well with existing diagnostic categories, our framework is directly applicable to clinical research and patient care.

19.
Hum Psychopharmacol ; 28(2): 183-7, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23364847

ABSTRACT

BACKGROUND: Previous studies have shown that antipsychotics with high propensity for antipsychotic-induced weight gain (AIWG) influence glucose transporter type 4 (GLUT4) mediated glucose intake. Variation in the gene encoding TBC1 domain family member 1 (TBC1D1), a Rab-GTPase activating protein regulating GLUT4 trafficking, has been associated with obesity. Therefore, we investigated the impact of TBC1D1 polymorphisms on AIWG. METHODS: We analyzed rs9852 and rs35859249 in TBC1D1 in 195 schizophrenia subjects treated mostly with clozapine or olanzapine for up to 14 weeks. Association was tested using analysis of variance and analysis of covariance with change (%) from baseline weight as the dependent variable. RESULTS: Analysis of covariance showed a non-significant trend for lower weight gain in carriers of the T-allele of rs9852 than in C-allele homozygotes (p = 0.063). This effect was more pronounced in the subgroup of patients treated with clozapine or olanzapine (p = 0.024). For rs35859249, no significant association with AIWG could be detected. CONCLUSIONS: This is the first study examining the association between TBC1D1 and AIWG. The moderate association of rs9852, located in the 3'UTR near a miRNA binding site, indicates an influence of TBC1D1 on AIWG. Further investigations remain necessary to elucidate the role of this gene in AIWG.


Subject(s)
Antipsychotic Agents/adverse effects , GTPase-Activating Proteins/genetics , Genetic Variation/genetics , Schizophrenia/genetics , Weight Gain/drug effects , Weight Gain/genetics , Adult , Female , Genetic Association Studies/methods , Humans , Male , Middle Aged , Schizophrenia/drug therapy
20.
Cells ; 12(5)2023 02 28.
Article in English | MEDLINE | ID: mdl-36899914

ABSTRACT

Type I interferons (IFNs) are central mediators of anti-viral and anti-bacterial host defence. Detection of microbes by innate immune cells via pattern recognition receptors (PRRs), including Toll-like receptors (TLRs) and cGAS-STING, induces the expression of type I IFN-stimulated genes. Primarily comprising the cytokines IFN-α and IFN-ß, type I IFNs act via the type I IFN receptor in an autocrine or exocrine manner to orchestrate rapid and diverse innate immune responses. Growing evidence pinpoints type I IFN signalling as a fulcrum that not only induces blood coagulation as a core feature of the inflammatory response but is also activated by components of the coagulation cascade. In this review, we describe in detail recent studies identifying the type I IFN pathway as a modulator of vascular function and thrombosis. In addition, we profile discoveries showing that thrombin signalling via protease-activated receptors (PARs), which can synergize with TLRs, regulates the host response to infection via induction of type I IFN signalling. Thus, type I IFNs can have both protective (via maintenance of haemostasis) and pathological (facilitating thrombosis) effects on inflammation and coagulation signalling. These can manifest as an increased risk of thrombotic complications in infection and in type I interferonopathies such as systemic lupus erythematosus (SLE) and STING-associated vasculopathy with onset in infancy (SAVI). We also consider the effects on coagulation of recombinant type I IFN therapies in the clinic and discuss pharmacological regulation of type I IFN signalling as a potential mechanism by which aberrant coagulation and thrombosis may be treated therapeutically.


Subject(s)
Interferon Type I , Antiviral Agents , Blood Coagulation , Cytokines/metabolism , Immunity, Innate , Interferon Type I/metabolism , Humans
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