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During the first hours after stroke onset, neurological deficits can be highly unstable: some patients rapidly improve, while others deteriorate. This early neurological instability has a major impact on long-term outcome. Here, we aimed to determine the genetic architecture of early neurological instability measured by the difference between the National Institutes of Health Stroke Scale (NIHSS) within 6â h of stroke onset and NIHSS at 24â h. A total of 5876 individuals from seven countries (Spain, Finland, Poland, USA, Costa Rica, Mexico and Korea) were studied using a multi-ancestry meta-analyses. We found that 8.7% of NIHSS at 24â h of variance was explained by common genetic variations, and also that early neurological instability has a different genetic architecture from that of stroke risk. Eight loci (1p21.1, 1q42.2, 2p25.1, 2q31.2, 2q33.3, 5q33.2, 7p21.2 and 13q31.1) were genome-wide significant and explained 1.8% of the variability suggesting that additional variants influence early change in neurological deficits. We used functional genomics and bioinformatic annotation to identify the genes driving the association from each locus. Expression quantitative trait loci mapping and summary data-based Mendelian randomization indicate that ADAM23 (log Bayes factor = 5.41) was driving the association for 2q33.3. Gene-based analyses suggested that GRIA1 (log Bayes factor = 5.19), which is predominantly expressed in the brain, is the gene driving the association for the 5q33.2 locus. These analyses also nominated GNPAT (log Bayes factor = 7.64) ABCB5 (log Bayes factor = 5.97) for the 1p21.1 and 7p21.1 loci. Human brain single-nuclei RNA-sequencing indicates that the gene expression of ADAM23 and GRIA1 is enriched in neurons. ADAM23, a presynaptic protein and GRIA1, a protein subunit of the AMPA receptor, are part of a synaptic protein complex that modulates neuronal excitability. These data provide the first genetic evidence in humans that excitotoxicity may contribute to early neurological instability after acute ischaemic stroke.
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Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Teorema de Bayes , Isquemia Encefálica/complicaciones , Isquemia Encefálica/genética , Estudio de Asociación del Genoma Completo , Humanos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/genética , Estados UnidosRESUMEN
Haemorrhagic transformation is a complication of recombinant tissue-plasminogen activator treatment. The most severe form, parenchymal haematoma, can result in neurological deterioration, disability, and death. Our objective was to identify single nucleotide variations associated with a risk of parenchymal haematoma following thrombolytic therapy in patients with acute ischaemic stroke. A fixed-effect genome-wide meta-analysis was performed combining two-stage genome-wide association studies (n = 1904). The discovery stage (three cohorts) comprised 1324 ischaemic stroke individuals, 5.4% of whom had a parenchymal haematoma. Genetic variants yielding a P-value < 0.05 1 × 10-5 were analysed in the validation stage (six cohorts), formed by 580 ischaemic stroke patients with 12.1% haemorrhagic events. All participants received recombinant tissue-plasminogen activator; cases were parenchymal haematoma type 1 or 2 as defined by the European Cooperative Acute Stroke Study (ECASS) criteria. Genome-wide significant findings (P < 5 × 10-8) were characterized by in silico functional annotation, gene expression, and DNA regulatory elements. We analysed 7â989â272 single nucleotide polymorphisms and identified a genome-wide association locus on chromosome 20 in the discovery cohort; functional annotation indicated that the ZBTB46 gene was driving the association for chromosome 20. The top single nucleotide polymorphism was rs76484331 in the ZBTB46 gene [P = 2.49 × 10-8; odds ratio (OR): 11.21; 95% confidence interval (CI): 4.82-26.55]. In the replication cohort (n = 580), the rs76484331 polymorphism was associated with parenchymal haematoma (P = 0.01), and the overall association after meta-analysis increased (P = 1.61 × 10-8; OR: 5.84; 95% CI: 3.16-10.76). ZBTB46 codes the zinc finger and BTB domain-containing protein 46 that acts as a transcription factor. In silico studies indicated that ZBTB46 is expressed in brain tissue by neurons and endothelial cells. Moreover, rs76484331 interacts with the promoter sites located at 20q13. In conclusion, we identified single nucleotide variants in the ZBTB46 gene associated with a higher risk of parenchymal haematoma following recombinant tissue-plasminogen activator treatment.
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Hemorragia Cerebral/inducido químicamente , Hemorragia Cerebral/genética , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Polimorfismo de Nucleótido Simple , Terapia Trombolítica/efectos adversos , Activador de Tejido Plasminógeno/efectos adversos , Factores de Transcripción/genética , Anciano , Anciano de 80 o más Años , Femenino , Fibrinolíticos/efectos adversos , Estudio de Asociación del Genoma Completo , Humanos , Accidente Cerebrovascular Isquémico/genética , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: Large-scale observational studies of acute ischemic stroke (AIS) promise to reveal mechanisms underlying cerebral ischemia. However, meaningful quantitative phenotypes attainable in large patient populations are needed. We characterize a dynamic metric of AIS instability, defined by change in National Institutes of Health Stroke Scale score (NIHSS) from baseline to 24 hours baseline to 24 hours (NIHSSbaseline - NIHSS24hours = ΔNIHSS6-24h), to examine its relevance to AIS mechanisms and long-term outcomes. METHODS: Patients with NIHSS prospectively recorded within 6 hours after onset and then 24 hours later were enrolled in the GENISIS study (Genetics of Early Neurological Instability After Ischemic Stroke). Stepwise linear regression determined variables that independently influenced ΔNIHSS6-24h. In a subcohort of tPA (alteplase)-treated patients with large vessel occlusion, the influence of early sustained recanalization and hemorrhagic transformation on ΔNIHSS6-24h was examined. Finally, the association of ΔNIHSS6-24h with 90-day favorable outcomes (modified Rankin Scale score 0-2) was assessed. Independent analysis was performed using data from the 2 NINDS-tPA stroke trials (National Institute of Neurological Disorders and Stroke rt-PA). RESULTS: For 2555 patients with AIS, median baseline NIHSS was 9 (interquartile range, 4-16), and median ΔNIHSS6-24h was 2 (interquartile range, 0-5). In a multivariable model, baseline NIHSS, tPA-treatment, age, glucose, site, and systolic blood pressure independently predicted ΔNIHSS6-24h (R2=0.15). In the large vessel occlusion subcohort, early sustained recanalization and hemorrhagic transformation increased the explained variance (R2=0.27), but much of the variance remained unexplained. ΔNIHSS6-24h had a significant and independent association with 90-day favorable outcome. For the subjects in the 2 NINDS-tPA trials, ΔNIHSS3-24h was similarly associated with 90-day outcomes. CONCLUSIONS: The dynamic phenotype, ΔNIHSS6-24h, captures both explained and unexplained mechanisms involved in AIS and is significantly and independently associated with long-term outcomes. Thus, ΔNIHSS6-24h promises to be an easily obtainable and meaningful quantitative phenotype for large-scale genomic studies of AIS.
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Accidente Cerebrovascular Isquémico , Recuperación de la Función , Índice de Severidad de la Enfermedad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Background and Purpose- Immune cells play a key role in the first 24h poststroke (acute phase), being associated with stroke outcome. We aimed to find genetic risk factors associated with leukocyte counts during the acute phase of stroke. Methods- Ischemic stroke patients with leukocyte counts data during the first 24h were included. Genome-wide association study and gene expression studies were performed. Results- Our genome-wide association study, which included 2064 (Discovery) and 407 (Replication) patients, revealed a new locus (14q24.3) associated with leukocyte counts. After Joint analysis (n=2471) 5 more polymorphisms reached genome-wide significance (P<5×10-8). The 14q24.3 locus was associated with acute stroke outcome (rs112809786, P=0.036) and with ACOT1 and PTGR2 gene expression. Previous polymorphisms associated with leukocyte counts in general-population did not show any significance in our study. Conclusions- We have found the first locus associated with leukocyte counts in ischemic stroke, also associated with acute outcome. Genetic analysis of acute endophenotypes could be useful to find the genetic factors associated with stroke outcome. Our findings suggested a different modulation of immune cells in stroke compared with healthy conditions.
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Isquemia Encefálica/inmunología , Recuento de Leucocitos , Leucocitos/inmunología , Accidente Cerebrovascular/inmunología , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/genética , Cromosomas Humanos Par 14/genética , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Pronóstico , Accidente Cerebrovascular/genéticaRESUMEN
Following the involvement of CHCHD10 in FrontoTemporal-Dementia-Amyotrophic Lateral Sclerosis (FTD-ALS) clinical spectrum, a founder mutation (p.Gly66Val) in the same gene was identified in Finnish families with late-onset spinal motor neuronopathy (SMAJ). SMAJ is a slowly progressive form of spinal muscular atrophy with a life expectancy within normal range. In order to understand why the p.Ser59Leu mutation, responsible for severe FTD-ALS, and the p.Gly66Val mutation could lead to different levels of severity, we compared their effects in patient cells. Unlike affected individuals bearing the p.Ser59Leu mutation, patients presenting with SMAJ phenotype have neither mitochondrial myopathy nor mtDNA instability. The expression of CHCHD10S59L mutant allele leads to disassembly of mitochondrial contact site and cristae organizing system (MICOS) with mitochondrial dysfunction and loss of cristae in patient fibroblasts. We also show that G66V fibroblasts do not display the loss of MICOS complex integrity and mitochondrial damage found in S59L cells. However, S59L and G66V fibroblasts show comparable accumulation of phosphorylated mitochondrial TDP-43 suggesting that the severity of phenotype and mitochondrial damage do not depend on mitochondrial TDP-43 localization. The expression of the CHCHD10G66V allele is responsible for mitochondrial network fragmentation and decreased sensitivity towards apoptotic stimuli, but with a less severe effect than that found in cells expressing the CHCHD10S59L allele. Taken together, our data show that cellular phenotypes associated with p.Ser59Leu and p.Gly66Val mutations in CHCHD10 are different; loss of MICOS complex integrity and mitochondrial dysfunction, but not TDP-43 mitochondrial localization, being likely essential to develop a severe motor neuron disease.
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Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/patología , Proteínas de Unión al ADN/genética , Demencia Frontotemporal/genética , Demencia Frontotemporal/patología , Mitocondrias/genética , Mitocondrias/patología , Proteínas Mitocondriales/genética , Adulto , Proteínas de Unión al ADN/análisis , Femenino , Células HEK293 , Células HeLa , Humanos , Masculino , Proteínas de la Membrana/análisis , Proteínas de la Membrana/genética , Persona de Mediana Edad , Mitocondrias/ultraestructura , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/patología , Proteínas Mitocondriales/análisis , Mutación/genética , Proteínas de Saccharomyces cerevisiae/análisis , Proteínas de Saccharomyces cerevisiae/genética , Índice de Severidad de la EnfermedadRESUMEN
Disrupted in Schizophrenia-1 (DISC1) has been associated with a broad spectrum of mental disorders. DISC1 is a multi-compartmentalized protein found in the cytoplasm, centrosome, nuclei and mostly enriched in mitochondria. In order to shed light on DISC1 mitochondrial function, we have studied its topology within the organelle. We show in here that in mammals DISC1 resides in the 'Mitochondrial contact site and Cristae Organizing system' (MICOS) complex, involved in cristae organization. DISC1 knockdown in SH-SY5Y cells causes MICOS disassembly and fragmentation of the mitochondrial morphology network. Moreover, DISC1 depleted cells have decreased mitochondrial DNA (mtDNA) content and steady state levels of oxidative phosphorylation (OXPHOS) subunits. As a consequence, OXPHOS complexes and supercomplexes are partially disassembled in DISC1 knockdown cells, which suffer severe bioenergetic defects, evidenced by impaired oxygen consumption, adenosine triphosphate synthesis and mitochondrial membrane potential. Transfection of recombinant full-length human DISC1 restores MICOS complex assembly and rescues OXPHOS function, meanwhile overexpression of the DISC1 truncated form Δ597-854, known to be pathogenic, fails to rescue the bioenergetic impairment caused by DISC1 knockdown. These results should contribute to reveal DISC1 physiological function and potential pathogenic role in severe mental illnesses.
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Metabolismo Energético/genética , Proteínas del Tejido Nervioso/genética , Fosforilación Oxidativa , Esquizofrenia/genética , Línea Celular , Centrosoma/metabolismo , ADN Mitocondrial/genética , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Potencial de la Membrana Mitocondrial/genética , Mitocondrias/genética , Mitocondrias/metabolismo , Complejos Multiproteicos/genética , Proteínas del Tejido Nervioso/biosíntesis , Esquizofrenia/metabolismo , Esquizofrenia/patología , TransfecciónRESUMEN
The role of neuronal surface autoantibodies (NSAs) in non-encephalitic psychosis is of recent and controversial interest. Most of the studies relating NSAs with psychosis are retrospective and only focused on the N-methyl-d-aspartate glutamate receptor (NMDAR). Our goal was to evaluate the prevalence of IgG antibodies against the NMDAR NR1 subunit (NMDAR-Abs) along with five additional NSAs in 61 first psychotic episode patients and 47 matched controls. We found two patients positive for NMDAR-Abs (3.3%). One of them was eventually considered to have been misdiagnosed and reclassified as encephalitis. The other met the criteria for bipolar I disorder, presented no neurological symptoms and had a comorbid HIV infection of vertical transmission. This is the first reported case of an HIV-infected patient with psychosis associated with NSAs. This study shows that patients presenting with clinically incomplete forms of anti-NMDAR encephalitis, with predominant or isolated psychiatric symptoms, can remain undetected if no ancillary tests are performed. To improve patient diagnosis and treatment of individuals with a first psychotic episode, more detailed neurological examinations might be needed. Further studies are required to better clarify the role of NSAs in the neuropsychiatric effects of HIV infection.
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Antígenos de Superficie/inmunología , Autoanticuerpos/sangre , Trastorno Bipolar/inmunología , Seropositividad para VIH/inmunología , Trastornos Psicóticos/inmunología , Receptores de N-Metil-D-Aspartato/inmunología , Adulto , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
Through GWAS studies we identified PATJ associated with functional outcome after ischemic stroke (IS). The aim of this study was to determine PATJ role in brain endothelial cells (ECs) in the context of stroke outcome. PATJ expression analyses in patient's blood revealed that: (i) the risk allele of rs76221407 induces higher expression of PATJ, (ii) PATJ is downregulated 24 h after IS, and (iii) its expression is significantly lower in those patients with functional independence, measured at 3 months with the modified Rankin scale ((mRS) ≤2), compared to those patients with marked disability (mRS = 4-5). In mice brains, PATJ was also downregulated in the injured hemisphere at 48 h after ischemia. Oxygen-glucose deprivation and hypoxia-dependent of Hypoxia Inducible Factor-1α also caused PATJ depletion in ECs. To study the effects of PATJ downregulation, we generated PATJ-knockdown human microvascular ECs. Their transcriptomic profile evidenced a complex cell reprogramming involving Notch, TGF-ß, PI3K/Akt, and Hippo signaling that translates in morphological and functional changes compatible with endothelial to mesenchymal transition (EndMT). PATJ depletion caused loss of cell-cell adhesion, upregulation of metalloproteases, actin cytoskeleton remodeling, cytoplasmic accumulation of the signal transducer C-terminal transmembrane Mucin 1 (MUC1-C) and downregulation of Notch and Hippo signaling. The EndMT phenotype of PATJ-depleted cells was associated with the nuclear recruitment of MUC1-C, YAP/TAZ, ß-catenin, and ZEB1. Our results suggest that PATJ downregulation 24 h after IS promotes EndMT, an initial step prior to secondary activation of a pro-angiogenic program. This effect is associated with functional independence suggesting that activation of EndMT shortly after stroke onset is beneficial for stroke recovery.
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Phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1) and PARK2/Parkin mutations cause autosomal recessive forms of Parkinson's disease. Upon a loss of mitochondrial membrane potential (DeltaPsi(m)) in human cells, cytosolic Parkin has been reported to be recruited to mitochondria, which is followed by a stimulation of mitochondrial autophagy. Here, we show that the relocation of Parkin to mitochondria induced by a collapse of DeltaPsi(m) relies on PINK1 expression and that overexpression of WT but not of mutated PINK1 causes Parkin translocation to mitochondria, even in cells with normal DeltaPsi(m). We also show that once at the mitochondria, Parkin is in close proximity to PINK1, but we find no evidence that Parkin catalyzes PINK1 ubiquitination or that PINK1 phosphorylates Parkin. However, co-overexpression of Parkin and PINK1 collapses the normal tubular mitochondrial network into mitochondrial aggregates and/or large perinuclear clusters, many of which are surrounded by autophagic vacuoles. Our results suggest that Parkin, together with PINK1, modulates mitochondrial trafficking, especially to the perinuclear region, a subcellular area associated with autophagy. Thus by impairing this process, mutations in either Parkin or PINK1 may alter mitochondrial turnover which, in turn, may cause the accumulation of defective mitochondria and, ultimately, neurodegeneration in Parkinson's disease.
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Autofagia/fisiología , Potencial de la Membrana Mitocondrial/fisiología , Mitocondrias/metabolismo , Proteínas Quinasas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Carbonil Cianuro m-Clorofenil Hidrazona/metabolismo , Línea Celular , Humanos , Ionóforos/metabolismo , Microtúbulos/metabolismo , Microtúbulos/ultraestructura , Mitocondrias/ultraestructura , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , Unión Proteica , Proteínas Quinasas/genética , Transporte de Proteínas/fisiología , Ubiquitina-Proteína Ligasas/genéticaRESUMEN
Background: Occult atrial fibrillation (AF) is one of the major causes of embolic stroke of undetermined source (ESUS). Knowing the underlying etiology of an ESUS will reduce stroke recurrence and/or unnecessary use of anticoagulants. Understanding cardioembolic strokes (CES), whose main cause is AF, will provide tools to select patients who would benefit from anticoagulants among those with ESUS or AF. We aimed to discover novel loci associated with CES and create a polygenetic risk score (PRS) for a more efficient CES risk stratification. Methods: Multitrait analysis of GWAS (MTAG) was performed with MEGASTROKE-CES cohort (n = 362,661) and AF cohort (n = 1,030,836). We considered significant variants and replicated those variants with MTAG p-value < 5 × 10-8 influencing both traits (GWAS-pairwise) with a p-value < 0.05 in the original GWAS and in an independent cohort (n = 9,105). The PRS was created with PRSice-2 and evaluated in the independent cohort. Results: We found and replicated eleven loci associated with CES. Eight were novel loci. Seven of them had been previously associated with AF, namely, CAV1, ESR2, GORAB, IGF1R, NEURL1, WIPF1, and ZEB2. KIAA1755 locus had never been associated with CES/AF, leading its index variant to a missense change (R1045W). The PRS generated has been significantly associated with CES improving discrimination and patient reclassification of a model with age, sex, and hypertension. Conclusion: The loci found significantly associated with CES in the MTAG, together with the creation of a PRS that improves the predictive clinical models of CES, might help guide future clinical trials of anticoagulant therapy in patients with ESUS or AF.
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We investigated the genetic causes of major mental disorders (MMDs) including schizophrenia, bipolar disorder I, major depressive disorder and attention deficit hyperactive disorder, in a large family pedigree from Alpujarras, South of Spain, a region with high prevalence of psychotic disorders. We applied a systematic genomic approach based on karyotyping (n = 4), genotyping by genome-wide SNP array (n = 34) and whole-genome sequencing (n = 12). We performed genome-wide linkage analysis, family-based association analysis and polygenic risk score estimates. Significant linkage was obtained at chromosome 9 (9q33.1-33.2, LOD score = 4.11), a suggestive region that contains five candidate genes ASTN2, BRINP1, C5, TLR4 and TRIM32, previously associated with MMDs. Comprehensive analysis associated the MMD phenotype with genes of the immune system with dual brain functions. Moreover, the psychotic phenotype was enriched for genes involved in synapsis. These results should be considered once studying the genetics of psychiatric disorders in other families, especially the ones from the same region, since founder effects may be related to the high prevalence.
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Proteínas de Ciclo Celular/genética , Glicoproteínas/genética , Proteínas del Tejido Nervioso/genética , Trastornos Psicóticos/genética , Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno Bipolar/genética , Cromosomas Humanos Par 9 , Trastorno Depresivo Mayor/genética , Femenino , Ligamiento Genético , Humanos , Masculino , Linaje , Polimorfismo de Nucleótido Simple , EspañaRESUMEN
Psychosis is a highly heritable and heterogeneous psychiatric condition. Its genetic architecture is thought to be the result of the joint effect of common and rare variants. Families with high prevalence are an interesting approach to shed light on the rare variant's contribution without the need of collecting large cohorts. To unravel the genomic architecture of a family enriched for psychosis, with four affected individuals, we applied a system genomic approach based on karyotyping, genotyping by whole-exome sequencing to search for rare single nucleotide variants (SNVs) and SNP array to search for copy-number variants (CNVs). We identified a rare non-synonymous variant, g.39914279 C > G, in the MACF1 gene, segregating with psychosis. Rare variants in the MACF1 gene have been previously detected in SCZ patients. Besides, two rare CNVs, DUP3p26.3 and DUP16q23.3, were also identified in the family affecting relevant genes (CNTN6 and CDH13, respectively). We hypothesize that the co-segregation of these duplications with the rare variant g.39914279 C > G of MACF1 gene precipitated with schizophrenia and schizoaffective disorder.
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Stroke is one of the most common causes of death and disability. Reperfusion therapies are the only treatment available during the acute phase of stroke. Due to recent clinical trials, these therapies may increase their frequency of use by extending the time-window administration, which may lead to an increase in complications such as hemorrhagic transformation, with parenchymal hematoma (PH) being the more severe subtype, associated with higher mortality and disability rates. Our aim was to find genetic risk factors associated with PH, as that could provide molecular targets/pathways for their prevention/treatment and study its genetic correlations to find traits sharing genetic background. We performed a GWAS and meta-analysis, following standard quality controls and association analysis (fastGWAS), adjusting age, NIHSS, and principal components. FUMA was used to annotate, prioritize, visualize, and interpret the meta-analysis results. The total number of patients in the meta-analysis was 2034 (216 cases and 1818 controls). We found rs79770152 having a genome-wide significant association (beta 0.09, p-value 3.90 × 10-8) located in the RP11-362K2.2:RP11-767I20.1 gene and a suggestive variant (rs13297983: beta 0.07, p-value 6.10 × 10-8) located in PCSK5 associated with PH occurrence. The genetic correlation showed a shared genetic background of PH with Alzheimer's disease and white matter hyperintensities. In addition, genes containing the ten most significant associations have been related to aggregated amyloid-ß, tau protein, white matter microstructure, inflammation, and matrix metalloproteinases.
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During the first hours after stroke onset neurological deficits can be highly unstable: some patients rapidly improve, while others deteriorate. This early neurological instability has a major impact on long-term outcome. Here, we aimed to determine the genetic architecture of early neurological instability measured by the difference between NIH stroke scale (NIHSS) within six hours of stroke onset and NIHSS at 24h (ΔNIHSS). A total of 5,876 individuals from seven countries (Spain, Finland, Poland, United States, Costa Rica, Mexico and Korea) were studied using a multi-ancestry meta-analyses. We found that 8.7% of ΔNIHSS variance was explained by common genetic variations, and also that early neurological instability has a different genetic architecture than that of stroke risk. Seven loci (2p25.1, 2q31.2, 2q33.3, 4q34.3, 5q33.2, 6q26 and 7p21.1) were genome-wide significant and explained 2.1% of the variability suggesting that additional variants influence early change in neurological deficits. We used functional genomics and bioinformatic annotation to identify the genes driving the association from each loci. eQTL mapping and SMR indicate that ADAM23 (log Bayes Factor (LBF)=6.34) was driving the association for 2q33.3. Gene based analyses suggested that GRIA1 (LBF=5.26), which is predominantly expressed in brain, is the gene driving the association for the 5q33.2 locus. These analyses also nominated PARK2 (LBF=5.30) and ABCB5 (LBF=5.70) for the 6q26 and 7p21.1 loci. Human brain single nuclei RNA-seq indicates that the gene expression of ADAM23 and GRIA1 is enriched in neurons. ADAM23 , a pre-synaptic protein, and GRIA1 , a protein subunit of the AMPA receptor, are part of a synaptic protein complex that modulates neuronal excitability. These data provides the first evidence in humans that excitotoxicity may contribute to early neurological instability after acute ischemic stroke. RESEARCH INTO CONTEXT: Evidence before this study: No previous genome-wide association studies have investigated the genetic architecture of early outcomes after ischemic stroke.Added Value of this study: This is the first study that investigated genetic influences on early outcomes after ischemic stroke using a genome-wide approach, revealing seven genome-wide significant loci. A unique aspect of this genetic study is the inclusion of all of the major ethnicities by recruiting from participants throughout the world. Most genetic studies to date have been limited to populations of European ancestry.Implications of all available evidence: The findings provide the first evidence that genes implicating excitotoxicity contribute to human acute ischemic stroke, and demonstrates proof of principle that GWAS of acute ischemic stroke patients can reveal mechanisms involved in ischemic brain injury.
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Acenocoumarol is an oral anticoagulant with significant interindividual dose variations. Variants in CYP2C9 and VKORC1 have been associated with acenocoumarol maintenance dose. We analysed whether any of the 49 polymorphisms in CYP2C9 and VKORC1 previously associated with acenocoumarol maintenance dose in a Genome-Wide Association study (GWAs) in Dutch population are associated with stroke recurrence, intracranial haemorrhage (ICH) and acenocoumarol maintenance dose in a Spanish population. We performed a GWAs using Human Core Exome-chip (Illumina) in 78 patients stroke patients treated with acenocoumarol for secondary prevention enrolled as part of the prospective investigator-initiated study (IIS) SEDMAN Study. Patients were followed-up a median of 12.8 months. Three and eight patients had recurrent stroke and ICH events, respectively. We found 14 of the 49 published variants associated with acenocoumarol maintenance dose (p < 0.05). Six polymorphisms were associated with stroke recurrence and four variants with ICH (p < 0.05). In conclusion, variants in VKORC1 and CYP2C9 are associated with acenocoumarol maintenance dose, stroke recurrence and ICH in a Spanish cohort. These results highlight the relevance of studying pharmacogenetics associated with efficacy and safety of anticoagulant drugs and justify studies with larger sample size and different ethnic populations.
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Acenocumarol , Anticoagulantes , Citocromo P-450 CYP2C9/genética , Accidente Cerebrovascular/tratamiento farmacológico , Vitamina K Epóxido Reductasas/genética , Acenocumarol/administración & dosificación , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Farmacogenética , Polimorfismo de Nucleótido Simple , Estudios Prospectivos , EspañaRESUMEN
OBJECTIVE: To validate the Genot-PA score, a clinical-genetic logistic regression score that stratifies the thrombolytic therapy safety, in a new cohort of patients with stroke. METHODS: We enrolled 1,482 recombinant tissue plasminogen activator (rtPA)-treated patients with stroke in Spain and Finland from 2003 to 2016. Cohorts were analyzed on the basis of ethnicity and therapy: Spanish patients treated with IV rtPA within 4.5 hours of onset (cohort A and B) or rtPA in combination with mechanical thrombectomy within 6 hours of onset (cohort C) and Finnish participants treated with IV rtPA within 4.5 hours of onset (cohort D). The Genot-PA score was calculated, and hemorrhagic transformation (HT) and parenchymal hematoma (PH) risks were determined for each score stratum. RESULTS: Genot-PA score was tested in 1,324 (cohort A, n = 726; B, n = 334; C, n = 54; and D, n = 210) patients who had enough information to complete the score. Of these, 213 (16.1%) participants developed HT and 85 (6.4%) developed PH. In cohorts A, B, and D, HT occurrence was predicted by the score (p = 2.02 × 10-6, p = 0.023, p = 0.033); PH prediction was associated in cohorts A through C (p = 0.012, p = 0.034, p = 5.32 × 10-4). Increased frequency of PH events from the lowest to the highest risk group was found (cohort A 4%-15.7%, cohort B 1.5%-18.2%, cohort C 0%-100%). The best odds ratio for PH prediction in the highest-risk group was obtained in cohort A (odds ratio 5.16, 95% confidence interval 1.46-18.08, p = 0.009). CONCLUSION: The Genot-PA score predicts HT in patients with stroke treated with IV rtPA. Moreover, in an exploratory study, the score was associated with PH risk in mechanical thrombectomy-treated patients.
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Hemorragia Cerebral/epidemiología , Valor Predictivo de las Pruebas , Activador de Tejido Plasminógeno/efectos adversos , Anciano , Anciano de 80 o más Años , Hemorragia Cerebral/inducido químicamente , Factor XII/genética , Femenino , Finlandia/epidemiología , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , España/epidemiología , Accidente Cerebrovascular/tratamiento farmacológico , Trombectomía/efectos adversos , Trombectomía/estadística & datos numéricos , Terapia Trombolítica/efectos adversos , Factores de Tiempo , Activador de Tejido Plasminógeno/uso terapéutico , alfa-Macroglobulinas/genéticaRESUMEN
Multiple sclerosis (MS) is considered a T cell-mediated autoimmune disease, although several evidences also demonstrate a B cell involvement in its etiology. Follicular T helper (Tfh) cells, a CXCR5-expressing CD4+ T cell subpopulation, are essential in the regulation of B cell differentiation and maintenance of humoral immunity. Alterations in circulating (c)Tfh distribution and/or function have been associated with autoimmune diseases including MS. Dimethyl fumarate (DMF) is a recently approved first-line treatment for relapsing-remitting MS (RRMS) patients whose mechanism of action is not completely understood. The aim of our study was to compare cTfh subpopulations between RRMS patients and healthy subjects and evaluate the impact of DMF treatment on these subpopulations, relating them to changes in B cells and humoral response. We analyzed, by flow cytometry, the distribution of cTfh1 (CXCR3+CCR6-), cTfh2 (CXCR3-CCR6-), cTfh17 (CXCR3-CCR6+), and the recently described cTfh17.1 (CXCR3+CCR6+) subpopulations of CD4+ Tfh (CD45RA-CXCR5+) cells in a cohort of 29 untreated RRMS compared to healthy subjects. CD4+ non-follicular T helper (Th) cells (CD45RA-CXCR5-) were also studied. We also evaluated the effect of DMF treatment on these subpopulations after 6 and 12 months treatment. Untreated RRMS patients presented higher percentages of cTfh17.1 cells and lower percentages of cTfh2 cells consistent with a pro-inflammatory bias compared to healthy subjects. DMF treatment induced a progressive increase in cTfh2 cells, accompanied by a decrease in cTfh1 and the pathogenic cTfh17.1 cells. A similar decrease of non-follicular Th1 and Th17.1 cells in addition to an increase in the anti-inflammatory Th2 subpopulation were also detected upon DMF treatment, accompanied by an increase in naïve B cells and a decrease in switched memory B cells and serum levels of IgA, IgG2, and IgG3. Interestingly, this effect was not observed in three patients in whom DMF had to be discontinued due to an absence of clinical response. Our results demonstrate a possibly pathogenic cTfh pro-inflammatory profile in RRMS patients, defined by high cTfh17.1 and low cTfh2 subpopulations that is reverted by DMF treatment. Monitoring cTfh subsets during treatment may become a biological marker of DMF effectiveness.
Asunto(s)
Dimetilfumarato/uso terapéutico , Inmunosupresores/uso terapéutico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/inmunología , Linfocitos T/inmunología , Adulto , Anciano , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Linfocitos B/metabolismo , Biomarcadores , Dimetilfumarato/farmacología , Femenino , Humanos , Inmunoglobulinas/sangre , Inmunoglobulinas/inmunología , Inmunofenotipificación , Inmunosupresores/farmacología , Estudios Longitudinales , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/metabolismo , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Resultado del TratamientoRESUMEN
It has been suggested that mutations in mitochondrial DNA (mtDNA) can produce an increase in reactive oxygen species (ROS) and that this can play a major role in the pathogenic mechanisms of mitochondrial encephalomyopathies. Many studies exist using electron transport chain (ETC) inhibitors, however there are only a few studies that examine ROS production associated with mutations in the mtDNA. To investigate this issue, we have studied ROS production, antioxidant defences and oxidative damage to lipids and proteins in transmitochondrial cybrids carrying different mtDNA mutations. Here, we report that two different mutant cell lines carrying mutations in their mitochondrial tRNA genes (A3243G in tRNA LeuUUR and A8344G in tRNA Lys) showed an increased ROS production with a parallel increase in the antioxidant enzyme activities, which may protect cells from oxidative damage in our experimental conditions (no overt oxidative damage to lipids and proteins has been observed). In contrast, cytochrome c oxidase (COX) mutant cybrids (carrying the stop-codon mutation G6930A in the COXI gene) showed neither an increase in ROS production nor elevation of antioxidant enzyme activities or oxidative damage. These results suggest that the specific location of mutations in mtDNA has a strong influence on the phenotype of the antioxidant response. Therefore, this issue should be carefully considered when antioxidant therapies are investigated in patients with mitochondrial disorders.
Asunto(s)
Antioxidantes/metabolismo , ADN Mitocondrial/genética , Metabolismo de los Lípidos , Osteosarcoma/genética , Osteosarcoma/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Adaptación Fisiológica/genética , Línea Celular Tumoral , Humanos , Células Híbridas , Mutación , Proteínas de Neoplasias/metabolismoRESUMEN
CHCHD10-related diseases include mitochondrial DNA instability disorder, frontotemporal dementia-amyotrophic lateral sclerosis (FTD-ALS) clinical spectrum, late-onset spinal motor neuropathy (SMAJ), and Charcot-Marie-Tooth disease type 2 (CMT2). Here, we show that CHCHD10 resides with mitofilin, CHCHD3 and CHCHD6 within the "mitochondrial contact site and cristae organizing system" (MICOS) complex. CHCHD10 mutations lead to MICOS complex disassembly and loss of mitochondrial cristae with a decrease in nucleoid number and nucleoid disorganization. Repair of the mitochondrial genome after oxidative stress is impaired in CHCHD10 mutant fibroblasts and this likely explains the accumulation of deleted mtDNA molecules in patient muscle. CHCHD10 mutant fibroblasts are not defective in the delivery of mitochondria to lysosomes suggesting that impaired mitophagy does not contribute to mtDNA instability. Interestingly, the expression of CHCHD10 mutant alleles inhibits apoptosis by preventing cytochrome c release.
Asunto(s)
Apoptosis/genética , Genoma Mitocondrial , Mitocondrias/genética , Proteínas Mitocondriales/genética , Alelos , Línea Celular , Citocromos c/metabolismo , Reparación del ADN/efectos de los fármacos , ADN Mitocondrial/análisis , ADN Mitocondrial/metabolismo , Células HeLa , Humanos , Peróxido de Hidrógeno/toxicidad , Lisosomas/metabolismo , Potencial de la Membrana Mitocondrial , Mitocondrias/metabolismo , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/patología , Proteínas Mitocondriales/metabolismo , Mutación , Estrés Oxidativo/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Genetic studies suggest that hundreds of genes associated with stroke remain unidentified. Exome sequencing proves useful for finding new genes associated with stroke. We aimed to find new genetic risk factors for cardioembolic stroke by analysing exome sequence data using new strategies. For discovery, we analysed 42 cardioembolic stroke cases and controls with extreme phenotypes (cohort 1), and for replication, 32 cardioembolic stroke cases and controls (cohort 2) using the SeqCapExome capture kit. We then analysed the replicated genes in two new cohorts that comprised 834 cardioembolic strokes and controls (cohort 3) and 64,373 cardioembolic strokes and controls (cohort 4). Transcriptomic in-silico functional analyses were also performed. We found 26 coding regions with a higher frequency of mutations in cardioembolic strokes after correcting for the number of mutations found in the whole exome of every patient. The TRPV3 gene was associated with cardioembolic stroke after replication of exome sequencing analysis (p-value-discovery: 0.018, p-value-replication: 0.014). The analysis of the TRPV3 gene using polymorphisms in cohort 3 and 4 revealed two polymorphisms associated with cardioembolic stroke in both cohorts, the most significant polymorphism being rs151091899 (p-value: 3.1 × 10-05; odds ratio: 5.4) in cohort 3. The genotype of one polymorphism of TRPV3 was associated with a differential expression of genes linked to cardiac malformations. In conclusion, new strategies using exome sequence data have revealed TRPV3 as a new gene associated with cardioembolic stroke. This strategy among others might be useful in finding new genes associated with complex genetic diseases.