Huntington's disease (HD) is caused by an aberrant expansion of CAG repeats in the HTT gene that mainly affects basal ganglia. Although striatal dysfunction has been widely studied in HD mouse models, other brain areas can also be relevant to the pathology. In this sense, we have special interest on the retina as this is the most exposed part of the central nervous system that enable health monitoring of patients using noninvasive techniques.
View Article and Find Full Text PDFHuntington's disease (HD) is a devastating neurodegenerative disorder caused by an aberrant expansion of CAG triplets in the (Huntingtin) gene [...
View Article and Find Full Text PDFThe retina is among the highest organized tissues of the central nervous system. To achieve such organization, a finely tuned regulation of developmental processes is required to form the retinal layers that contain the specialized neurons and supporting glial cells to allow precise phototransduction. MicroRNAs are a class of small RNAs with undoubtful roles in fundamental biological processes, including neurodevelopment of the brain and the retina.
View Article and Find Full Text PDFGlioblastoma (GB) is the most prevalent primary brain cancer and the most aggressive form of glioma because of its poor prognosis and high recurrence. To confirm the importance of epigenetics in glioma, we explored The Cancer Gene Atlas (TCGA) database and we found that several histone/DNA modifications and chromatin remodeling factors were affected at transcriptional and genetic levels in GB compared to lower-grade gliomas. We associated these alterations in our own cohort of study with a significant reduction in the bulk levels of acetylated lysines 9 and 14 of histone H3 in high-grade compared to low-grade tumors.
View Article and Find Full Text PDFEnvironmental factors and life experiences impinge on brain circuits triggering adaptive changes. Epigenetic regulators contribute to this neuroadaptation by enhancing or suppressing specific gene programs. The paralogous transcriptional coactivators and lysine acetyltransferases CREB binding protein (CBP) and p300 are involved in brain plasticity and stimulus-dependent transcription, but their specific roles in neuroadaptation are not fully understood.
View Article and Find Full Text PDFHuntington's disease (HD) is a devastating neurodegenerative disorder that is caused by an abnormal expansion of CAG repeats in the Huntingtin () gene. Although the main symptomatology is explained by alterations at the level of the central nervous system, predominantly affecting the basal ganglia, a peripheral component of the disease is being increasingly acknowledged. Therefore, the manifestation of the disease is complex and variable among CAG expansion carriers, introducing uncertainty in the appearance of specific signs, age of onset and severity of disease.
View Article and Find Full Text PDFGlioblastoma (GB) is the most aggressive form of glioma and is characterized by poor prognosis and high recurrence despite intensive clinical interventions. To retrieve the key factors underlying the high malignancy of GB with potential diagnosis utility, we combined the analysis of The Cancer Gene Atlas and the REMBRANDT datasets plus a molecular examination of our own collection of surgical tumor resections. We determined a net reduction in the levels of the non-canonical histone H3 variant H3.
View Article and Find Full Text PDFAbnormal trinucleotide expansions cause rare disorders that compromise quality of life and, in some cases, lifespan. In particular, the expansions of the CGG-repeats stretch at the 5'-UTR of the Fragile X Mental Retardation 1 () gene have pleiotropic effects that lead to a variety of Fragile X-associated syndromes: the neurodevelopmental Fragile X syndrome (FXS) in children, the late-onset neurodegenerative disorder Fragile X-associated tremor-ataxia syndrome (FXTAS) that mainly affects adult men, the Fragile X-associated primary ovarian insufficiency (FXPOI) in adult women, and a variety of psychiatric and affective disorders that are under the term of Fragile X-associated neuropsychiatric disorders (FXAND). In this review, we will describe the pathological mechanisms of the adult "gain-of-function" syndromes that are mainly caused by the toxic actions of CGG RNA and FMRpolyG peptide.
View Article and Find Full Text PDFDuring surgical procedures for gliomas, tissue material obtained from cavitational ultrasonic surgical aspirators (CUSAs) is generally discarded but can actually exceed the amount and quality of certain tumour core resections (TCRs). Despite reports indicating the suitability of CUSA-derived material for diagnosis and research, its use is still marginal. We extended these conclusions to formalin-fixed, paraffin-embedded (FFPE) samples, the most common format for archival tumour tissue in anatomical pathology departments, by conducting for the first time RNA-seq analysis in CUSA aspirates.
View Article and Find Full Text PDFGlioblastoma (GBM) is the most frequent and aggressive primary brain tumor and is associated with a poor prognosis. Despite the use of combined treatment approaches, recurrence is almost inevitable and survival longer than 14 or 15 months after diagnosis is low. It is therefore necessary to identify new therapeutic targets to fight GBM progression and recurrence.
View Article and Find Full Text PDFGlioma stem cells (GSCs) are crucial in the formation, perpetuation and recurrence of glioblastomas (GBs) due to their self-renewal and proliferation properties. Although GSCs share cellular and molecular characteristics with neural stem cells (NSCs), GSCs show unique transcriptional and epigenetic features that may explain their relevant role in GB and may constitute druggable targets for novel therapeutic approaches. In this review, we will summarize the most important findings in GSCs concerning epigenetic-dependent mechanisms.
View Article and Find Full Text PDFMultiple myeloma (MM) is a B-cell neoplasm that is characterized by the accumulation of malignant plasma cells in the bone marrow. The transcription factor PRDM1 is a master regulator of plasma cell development and is considered to be an oncosuppressor in several lymphoid neoplasms. The PRDM1β isoform is an alternative promoter of the PRDM1 gene that may interfere with the normal role of the PRDM1α isoform.
View Article and Find Full Text PDFMalformations of cortical development (MCDs) are neurodevelopmental disorders that result from abnormal development of the cerebral cortex in utero. MCDs place a substantial burden on affected individuals, their families and societies worldwide, as these individuals can experience lifelong drug-resistant epilepsy, cerebral palsy, feeding difficulties, intellectual disability and other neurological and behavioural anomalies. The diagnostic pathway for MCDs is complex owing to wide variations in presentation and aetiology, thereby hampering timely and adequate management.
View Article and Find Full Text PDFHuntington disease (HD) is a fatal neurodegenerative disorder without a cure that is caused by an aberrant expansion of CAG repeats in exon 1 of the huntingtin (HTT) gene. Although a negative correlation between the number of CAG repeats and the age of disease onset is established, additional factors may contribute to the high heterogeneity of the complex manifestation of symptoms among patients. This variability is also observed in mouse models, even under controlled genetic and environmental conditions.
View Article and Find Full Text PDFThe CREB-binding protein (CBP) exerts tight control of developmental processes. Here, we investigated the consequences of its selective ablation in newborn neurons. Mice in which CBP was eliminated during neuronal differentiation showed perinatal death and defective diaphragm innervation.
View Article and Find Full Text PDFTranscriptional dysregulation in Huntington's disease (HD) affects the expression of genes involved in survival and neuronal functions throughout the progression of the pathology. In recent years, extensive research has focused on epigenetic and chromatin-modifying factors as a causative explanation for such dysregulation, offering attractive targets for pharmacological therapies. In this work, we extensively examined the gene expression profiles in the cortex, striatum, hippocampus and cerebellum of juvenile R6/1 and N171-82Q mice, models of rapidly progressive HD, to retrieve the early transcriptional signatures associated with this pathology.
View Article and Find Full Text PDFThe genetic alphabet consists of the four letters: C, A, G, and T in DNA and C,A,G, and U in RNA. Triplets of these four letters jointly encode 20 different amino acids out of which proteins of all organisms are built. This system is universal and is found in all kingdoms of life.
View Article and Find Full Text PDFPlasma cells (PC) represent the heterogeneous final stage of the B cells (BC) differentiation process. To characterize the transition of BC into PC, transcriptomes from human naïve BC were compared to those of three functionally-different subsets of human in vivo-generated PC: i) tonsil PC, mainly consisting of early PC; ii) PC released to the blood after a potent booster-immunization (mostly cycling plasmablasts); and, iii) bone marrow CD138+ PC that represent highly mature PC and include the long-lived PC compartment. This transcriptional transition involves subsets of genes related to key processes for PC maturation: the already known protein processing, apoptosis and homeostasis, and of new discovery including histones, macromolecule assembly, zinc-finger transcription factors and neuromodulation.
View Article and Find Full Text PDFThe cyclic AMP response element binding protein (CREB) is a primary hub of activity-driven genetic programs in neurons controlling plasticity, neurogenesis and survival. By contrast, the gene networks coordinated by CREB in astrocytes are unknown despite the fact that the astrocytic CREB is also activity-driven and neuroprotective. Herein we identified the transcriptional programs regulated by CREB in astrocytes as compared to neurons using, as study materials, transcriptome databases of astrocyte exposed to well-known activators of CREB-dependent transcription as well as publicly available transcriptomes of neuronal cultures.
View Article and Find Full Text PDFThe clinical challenge in acute injury as in traumatic brain injury (TBI) is to halt the delayed neuronal loss that occurs hours and days after the insult. Here we report that the activation of CREB-dependent transcription in reactive astrocytes prevents secondary injury in cerebral cortex after experimental TBI. The study was performed in a novel bitransgenic mouse in which a constitutively active CREB, VP16-CREB, was targeted to astrocytes with the Tet-Off system.
View Article and Find Full Text PDFDefective epigenetic regulation has been postulated as a possible cause for the extensive and premature transcriptional dysregulation observed in experimental models of Huntington's disease (HD). In this study, we extended our observations in the N171-82Q mouse strain relating to the limited impact of polyQ pathology on the global histone acetylation to other animal and cellular models of HD, namely the R6/1 and YAC128 strains, striatal-electroporated mice, primary neuronal cultures and stably transfected PC12 cells. In the absence of bulk chromatin changes, we nonetheless documented histone deacetylation events at the transcription start sites (TSS) of genes relevant to neuronal functions (e.
View Article and Find Full Text PDFInt J Biochem Cell Biol
October 2015
The study of epigenetics is providing novel insights about the functional and developmental complexity of the nervous system. In neuropathology, therapies aimed at correcting epigenetic dysregulation have been extensively documented in a large variety of models for neurodegenerative, neurodevelopmental and psychiatric disorders. Taking the treatment of Huntington's disease as a paradigm for the study of these ameliorative strategies, this review updates the main conclusions derived from the use of epigenetic drugs at the preclinical and clinical stages, including actions beyond epigenetics.
View Article and Find Full Text PDFOrexins (OX) have been recently implicated in ethanol seeking and self-administration. A few recent studies have provided additional evidence that OX receptor antagonists effectively reduce voluntary ethanol consumption in subjects spontaneously showing high levels of ethanol intake. The present study further evaluates the contribution of OXR1 to excessive binge-like drinking of ethanol in ad libitum-fed C57BL/6J mice from a pharmacological and molecular approach.
View Article and Find Full Text PDFThe number of genetic syndromes associated with intellectual disability that are caused by mutations in genes encoding chromatin-modifying enzymes has sharply risen in the last decade. We discuss here a neurodevelopmental disorder, the Rubinstein-Taybi syndrome (RSTS), originated by mutations in the genes encoding the lysine acetyltransferases CBP and p300. We first describe clinical and genetic aspects of the syndrome to later focus on the insight provided by the research in animal models of this disease.
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