RESUMEN
INTRODUCTION: Omics studies have revealed that various brain cell types undergo profound molecular changes in Alzheimer's disease (AD) but the spatial relationships with plaques and tangles and APOE-linked differences remain unclear. METHODS: We performed laser capture microdissection of amyloid beta (Aß) plaques, the 50 µm halo around them, tangles with the 50 µm halo around them, and areas distant (> 50 µm) from plaques and tangles in the temporal cortex of AD and control donors, followed by RNA-sequencing. RESULTS: Aß plaques exhibited upregulated microglial (neuroinflammation/phagocytosis) and downregulated neuronal (neurotransmission/energy metabolism) genes, whereas tangles had mostly downregulated neuronal genes. Aß plaques had more differentially expressed genes than tangles. We identified a gradient Aß plaque > peri-plaque > tangle > distant for these changes. AD APOE ε4 homozygotes had greater changes than APOE ε3 across locations, especially within Aß plaques. DISCUSSION: Transcriptomic changes in AD consist primarily of neuroinflammation and neuronal dysfunction, are spatially associated mainly with Aß plaques, and are exacerbated by the APOE ε4 allele.
Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Ovillos Neurofibrilares , Apolipoproteína E4/genética , Enfermedades Neuroinflamatorias , Encéfalo/metabolismo , Transcriptoma , Placa Amiloide/metabolismo , Perfilación de la Expresión GénicaRESUMEN
INTRODUCTION: Omics studies have revealed that various brain cell types undergo profound molecular changes in Alzheimer's disease (AD) but the spatial relationships with plaques and tangles and APOE -linked differences remain unclear. METHODS: We performed laser capture microdissection of Aß plaques, the 50µm halo around them, tangles with the 50µm halo around them, and areas distant (>50µm) from plaques and tangles in the temporal cortex of AD and control donors, followed by RNA-sequencing. RESULTS: Aß plaques exhibited upregulated microglial (neuroinflammation/phagocytosis) and downregulated neuronal (neurotransmission/energy metabolism) genes, whereas tangles had mostly downregulated neuronal genes. Aß plaques had more differentially expressed genes than tangles. We identified a gradient Aß plaque>peri-plaque>tangle>distant for these changes. AD APOE ε4 homozygotes had greater changes than APOE ε3 across locations, especially within Aß plaques. DISCUSSION: Transcriptomic changes in AD consist primarily of neuroinflammation and neuronal dysfunction, are spatially associated mainly with Aß plaques, and are exacerbated by the APOE ε4 allele.
RESUMEN
Alzheimer's disease (AD) is a common neurodegenerative disease with poor prognosis. New options for drug discovery targets are needed. We developed an imaging based arrayed CRISPR method to interrogate the human genome for modulation of in vitro correlates of AD features, and used this to assess 1525 human genes related to tau aggregation, autophagy and mitochondria. This work revealed (I) a network of tau aggregation modulators including the NF-κB pathway and inflammatory signaling, (II) a correlation between mitochondrial morphology, respiratory function and transcriptomics, (III) machine learning predicted novel roles of genes and pathways in autophagic processes and (IV) individual gene function inferences and interactions among biological processes via multi-feature clustering. These studies provide a platform to interrogate underexplored aspects of AD biology and offer several specific hypotheses for future drug discovery efforts.
Asunto(s)
Enfermedad de Alzheimer/genética , Autofagia/genética , Modelos Genéticos , Agregación Patológica de Proteínas/genética , Proteínas tau/metabolismo , Enfermedad de Alzheimer/patología , Encéfalo/patología , Sistemas CRISPR-Cas/genética , Línea Celular Tumoral , Regulación de la Expresión Génica , Ingeniería Genética , Humanos , Aprendizaje Automático , Mitocondrias/genética , Mitocondrias/patología , Neuronas , Agregación Patológica de Proteínas/patología , Transducción de Señal/genéticaRESUMEN
BACKGROUND: The identification of biomarkers that predict susceptibility to major depressive disorder and treatment response to antidepressants is a major challenge. Vortioxetine is a novel multimodal antidepressant that possesses pro-cognitive properties and differentiates from other conventional antidepressants on various cognitive and plasticity measures. The aim of the present study was to identify biological systems rather than single biomarkers that may underlie vortioxetine's treatment effects. RESULTS: We show that the biological systems regulated by vortioxetine are overlapping between mouse and rat in response to distinct treatment regimens and in different brain regions. Furthermore, analysis of complexes of physically-interacting proteins reveal that biomarkers involved in transcriptional regulation, neurodevelopment, neuroplasticity, and endocytosis are modulated by vortioxetine. A subsequent qPCR study examining the expression of targets in the protein-protein interactome space in response to chronic vortioxetine treatment over a range of doses provides further biological validation that vortioxetine engages neuroplasticity networks. Thus, the same biology is regulated in different species and sexes, different brain regions, and in response to distinct routes of administration and regimens. CONCLUSIONS: A recurring theme, based on the present study as well as previous findings, is that networks related to synaptic plasticity, synaptic transmission, signal transduction, and neurodevelopment are modulated in response to vortioxetine treatment. Regulation of these signaling pathways by vortioxetine may underlie vortioxetine's cognitive-enhancing properties.
Asunto(s)
Antidepresivos/farmacología , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Piperazinas/farmacología , Sulfuros/farmacología , Animales , Corteza Cerebral/crecimiento & desarrollo , Femenino , Expresión Génica/efectos de los fármacos , Hipocampo/crecimiento & desarrollo , Masculino , Ratones Endogámicos C57BL , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/fisiología , Mapeo de Interacción de Proteínas , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , Estudios Retrospectivos , Especificidad de la Especie , VortioxetinaRESUMEN
Alzheimer's disease (AD) is strongly associated with microglia-induced neuroinflammation. Particularly, Aß plaque-associated microglia take on an "activated" morphology. However, the function and phenotype of these Aß plaque-associated microglia are not well understood. We show hyperreactivity of Aß plaque-associated microglia upon systemic inflammation in transgenic AD mouse models (i.e., 5XFAD and APP23). Gene expression profiling of Aß plaque-associated microglia (major histocompatibility complex II+ microglia) isolated from 5XFAD mice revealed a proinflammatory phenotype. The upregulated genes involved in the biological processes (gene ontology terms) included: "immune response to external stimulus" such as Axl, Cd63, Egr2, and Lgals3, "cell motility", such as Ccl3, Ccl4, Cxcr4, and Sdc3, "cell differentiation", and "system development", such as St14, Trpm1, and Spp1. In human AD tissue with similar Braak stages, expression of phagocytic markers and AD-associated genes, including HLA-DRA, APOE, AXL, TREM2, and TYROBP, was higher in laser-captured early-onset AD (EOAD) plaques than in late-onset AD plaques. Interestingly, the nonplaque parenchyma of both EOAD and late-onset AD brains, the expression of above-mentioned markers were similarly low. Here, we provide evidence that Aß plaque-associated microglia are hyperreactive in their immune response and phagocytosis in the transgenic AD mice as well as in EOAD brain tissue. We suggest that Aß plaque-associated microglia are the primary source of neuroinflammation related to AD pathology.
Asunto(s)
Enfermedad de Alzheimer/inmunología , Péptidos beta-Amiloides/inmunología , Microglía/inmunología , Placa Amiloide/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/genética , Animales , Apolipoproteínas E , Encéfalo/inmunología , Diferenciación Celular/genética , Movimiento Celular/genética , Movimiento Celular/inmunología , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Humanos , Inflamación/genética , Inflamación/inmunología , Masculino , Glicoproteínas de Membrana , Ratones Transgénicos , Persona de Mediana Edad , Fagocitosis/genética , Fagocitosis/inmunología , Proteínas Proto-Oncogénicas , Proteínas Tirosina Quinasas Receptoras , Receptores Inmunológicos , Tirosina Quinasa del Receptor AxlRESUMEN
The multimodal antidepressant vortioxetine displays an antidepressant profile distinct from those of conventional selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) and possesses cognitive-enhancing properties in preclinical and clinical studies. Recent studies have begun to investigate molecular mechanisms that may differentiate vortioxetine from other antidepressants. Acute studies in adult rats and chronic studies in a middle-aged mouse model reveal upregulation of several markers that play a central role in synaptic plasticity. However, the effect of chronic vortioxetine treatment on expression of neuroplasticity and neurodevelopmental biomarkers in naïve rats has not been evaluated. In the present study, we demonstrate that vortioxetine at a range of doses regulates expression of genes associated with plasticity in the frontal cortex, hippocampus, region encompassing the amygdala, as well as in blood, and displays similar effects relative to the SSRI fluoxetine in adult naïve rats. These genes encode immediate early genes (IEGs), translational regulators, and the neurodevelopmental marker Sema4g. Similar findings detected in brain regions and in blood provide a potential translational impact, and vortioxetine appears to consistently regulate signaling in these networks of neuroplasticity and developmental markers.
Asunto(s)
Piperazinas/farmacología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Sulfuros/farmacología , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/metabolismo , Animales , Antidepresivos/farmacología , Biomarcadores/sangre , Fluoxetina , Lóbulo Frontal/efectos de los fármacos , Lóbulo Frontal/metabolismo , Expresión Génica/efectos de los fármacos , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , VortioxetinaRESUMEN
Neuroplasticity is fundamental for brain functions, abnormal changes of which are associated with mood disorders and cognitive impairment. Neuroplasticity can be affected by neuroactive medications and by aging. Vortioxetine, a multimodal antidepressant, has shown positive effects on cognitive functions in both pre-clinical and clinical studies. In rodent studies, vortioxetine increases glutamate neurotransmission, promotes dendritic branching and spine maturation, and elevates hippocampal expression of the activity-regulated cytoskeleton-associated protein (Arc/Arg3.1) at the transcript level. The present study aims to assess the effects of vortioxetine on several neuroplasticity-related molecules in different experimental systems. Chronic (1 month) vortioxetine increased Arc/Arg3.1 protein levels in the cortical synaptosomes of young and middle-aged mice. In young mice, this was accompanied by an increase in actin-depolymerizing factor (ADF)/cofilin serine 3 phosphorylation without altering the total ADF/cofilin protein level, and an increase in the GluA1 subunit of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor phosphorylation at serine 845 (S845) without altering serine 831 (S831) GluA1 phosphorylation nor the total GluA1 protein level. Similar effects were detected in cultured rat hippocampal neurons: Acute vortioxetine increased S845 GluA1 phosphorylation without changing S831 GluA1 phosphorylation or the total GluA1 protein level. These changes were accompanied by an increase in α subunit of Ca2+/calmodulin-dependent kinase (CaMKIIα) phosphorylation (at threonine 286) without changing the total CaMKIIα protein level in cultured neurons. In addition, chronic (1 month) vortioxetine, but not fluoxetine, restored the age-associated reduction in Arc/Arg3.1 and c-Fos transcripts in the frontal cortex of middle-aged mice. Taken together, these results demonstrated that vortioxetine modulates molecular targets that are related to neuroplasticity.
Asunto(s)
Plasticidad Neuronal/efectos de los fármacos , Piperazinas/farmacología , Sulfuros/farmacología , Animales , Antidepresivos/farmacología , Proteínas del Citoesqueleto/metabolismo , Femenino , Lóbulo Frontal/efectos de los fármacos , Lóbulo Frontal/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Ratones , Ratones Endogámicos C57BL , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Fosforilación/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptores AMPA/metabolismo , Serina/metabolismo , VortioxetinaRESUMEN
Cognitive decline occurs during healthy aging, even in middle-aged subjects, via mechanisms that could include reduced stem cell proliferation, changed growth factor expression and/or reduced expression of synaptic plasticity genes. Although antidepressants alter these mechanisms in young rodents, their effects in older animals are unclear. In middle-aged mice, we examined the effects of a selective serotonin reuptake inhibitor (fluoxetine) and a multimodal antidepressant (vortioxetine) on cognitive and affective behaviors, brain stem cell proliferation, growth factor and gene expression. Twelve-month-old female C57BL/6 mice exhibited impaired visuospatial memory in the novel object placement (location) task associated with reduced expression of several plasticity-related genes. Chronic treatment with vortioxetine, but not fluoxetine, improved visuospatial memory and reduced depression-like behavior in the forced swim test in middle-aged mice. Vortioxetine, but not fluoxetine, increased hippocampal expression of several neuroplasticity-related genes in middle-aged mice (e.g., Nfkb1, Fos, Fmr1, Camk2a, Arc, Shank1, Nlgn2, and Rab3a). Neither drug reversed the age-associated decrease in stem cell proliferation. Hippocampal growth factor levels were not consistent with behavioral outcomes. Thus, a change in the expression of multiple genes involved in neuronal plasticity by antidepressant treatment was associated with improved cognitive function and a reduction in depression-like behavior in middle-aged mice.
Asunto(s)
Envejecimiento/psicología , Antidepresivos/farmacología , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/psicología , Expresión Génica/efectos de los fármacos , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/genética , Animales , Antidepresivos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Femenino , Fluoxetina/farmacología , Fluoxetina/uso terapéutico , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/genética , Ratones , Ratones Endogámicos C57BL , Actividad Motora/efectos de los fármacos , Células-Madre Neurales/efectos de los fármacos , Piperazinas/farmacología , Piperazinas/uso terapéutico , Reconocimiento en Psicología/efectos de los fármacos , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Sulfuros/farmacología , Sulfuros/uso terapéutico , Natación/psicología , VortioxetinaRESUMEN
The biological underpinnings of borderline personality disorder (BPD) and its psychopathology including states of aversive tension and dissociation is poorly understood. Our goal was to examine transcriptional changes associated with states of tension or dissociation within individual patients in a pilot study. Dissociation is not only a critical symptom of BPD but has also been associated with higher risk for self-mutilation and depression. We conducted a whole blood gene expression profile analysis using quantitative PCR in 31 female inpatients with BPD. For each individual, two samples were drawn during a state of high tension and dissociation, while two samples were drawn at non-tension states. There was no association between gene expression and tension states. However, we could show that Interleukin-6 was positively correlated to dissociation scores, whereas Guanine nucleotide-binding protein G(s) subunit alpha isoforms, Mitogen-activated protein kinase 3 and 8, Guanine nucleotide-binding protein G(i) subunit alpha-2, Beta-arrestin-1 and 2, and Cyclic AMP-responsive element-binding protein were negatively correlated to dissociation. Our data point to a potential association of dissociation levels with the expression of genes involved in immune system regulation as well as cellular signalling/second-messenger systems. Major limitations of the study are the the possibly heterogeneous cell proportions in whole blood and the heterogeneous medication.