35 research outputs found
Loss of the thyroid hormone-binding protein Crym renders striatal neurons more vulnerable to mutant huntingtin in Huntington's disease.
The mechanisms underlying preferential atrophy of the striatum in Huntington's disease (HD) are unknown. One hypothesis is that a set of gene products preferentially expressed in the striatum could determine the particular vulnerability of this brain region to mutant huntingtin (mHtt). Here, we studied the striatal protein µ-crystallin (Crym). Crym is the NADPH-dependent p38 cytosolic T3-binding protein (p38CTBP), a key regulator of thyroid hormone (TH) T3 (3,5,3'-triiodo-l-thyronine) transportation. It has been also recently identified as the enzyme that reduces the sulfur-containing cyclic ketimines, which are potential neurotransmitters. Here, we confirm the preferential expression of the Crym protein in the rodent and macaque striatum. Crym expression was found to be higher in the macaque caudate than in the putamen. Expression of Crym was reduced in the BACHD and Knock-in 140CAG mouse models of HD before onset of striatal atrophy. We show that overexpression of Crym in striatal medium-size spiny neurons using a lentiviral-based strategy in mice is neuroprotective against the neurotoxicity of an N-terminal fragment of mHtt in vivo. Thus, reduction of Crym expression in HD could render striatal neurons more susceptible to mHtt suggesting that Crym may be a key determinant of the vulnerability of the striatum. In addition our work points to Crym as a potential molecular link between striatal degeneration and the THs deregulation reported in HD patients
PREPARO QUÍMICO MECÂNICO DOS CONDUTOS RADICULARES: ANÁLISE COMPARATIVA DA FORMAÇÃO DO DESVIO APICAL “ZIP” EM CANAIS CUR- VOS PRODUZIDO “IN VITRO” POR TÉCNICAS DE INSTRUMENTAÇÃO.
Os autores descrevem a instrumentação com instrumentos de níquel - titânio (Pow-R) acionados amotor e instrumentação manual com limas de aço inoxidável. As técnicas foram realizadas emblocos de resina transparente e comparadas entre si em diversas fases, sendo discutidas as suasvantagens e desvantagens. A análise dos resultados permite verificar maior incidência de desvioapical para a técnica de preparo manual (limas de aço inoxidável) do que para o sistema de rotação contínua Pow – R.Palavras chave: Instrumentos endodonticos; Desvio apical; Tratamento dos condutos radiculares; Preparo docanal
Transcriptional correlates of the pathological phenotype in a Huntington’s disease mouse model
Huntington 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. To better understand this phenomenon, we analysed the R6/1 strain
in search of potential correlates between pathological motor/cognitive phenotypical traits and
transcriptional alterations. HD-related genes (e.g., Penk, Plk5, Itpka), despite being downregulated
across the examined brain areas (the prefrontal cortex, striatum, hippocampus and cerebellum),
exhibited tissue-specific correlations with particular phenotypical traits that were attributable to
the contribution of the brain region to that trait (e.g., striatum and rotarod performance, cerebellum
and feet clasping). Focusing on the striatum, we determined that the transcriptional dysregulation
associated with HD was partially exacerbated in mice that showed poor overall phenotypical scores,
especially in genes with relevant roles in striatal functioning (e.g., Pde10a, Drd1, Drd2, Ppp1r1b).
However, we also observed transcripts associated with relatively better outcomes, such as Nfya
(CCAAT-binding transcription factor NF-Y subunit A) plus others related to neuronal development,
apoptosis and differentiation. In this study, we demonstrated that altered brain transcription can be
related to the manifestation of HD-like symptoms in mouse models and that this can be extrapolated to
the highly heterogeneous population of HD patients
Contribution of Neuroepigenetics to Huntington’s Disease
\ua9 2017 Francelle, Lotz, Outeiro, Brouillet and Merienne. Unbalanced epigenetic regulation is thought to contribute to the progression of several neurodegenerative diseases, including Huntington’s disease (HD), a genetic disorder considered as a paradigm of epigenetic dysregulation. In this review, we attempt to address open questions regarding the role of epigenetic changes in HD, in the light of recent advances in neuroepigenetics. We particularly discuss studies using genome-wide scale approaches that provide insights into the relationship between epigenetic regulations, gene expression and neuronal activity in normal and diseased neurons, including HD neurons. We propose that cell-type specific techniques and 3D-based methods will advance knowledge of epigenome in the context of brain region vulnerability in neurodegenerative diseases. A better understanding of the mechanisms underlying epigenetic changes and of their consequences in neurodegenerative diseases is required to design therapeutic strategies more effective than current strategies based on histone deacetylase (HDAC) inhibitors. Researches in HD may play a driving role in this process
Biological Features of Herpes Simplex Virus Type 1 Latency in Mice According to Experimental Conditions and Type of Neurones
International audienc
A bittersweet treat: Impact of OFW remittances on labor hours worked per week using selected socio-demographic variables of the household head
Remittances play a very important part to the households that receive them. Remittances are money endowed by migrants to their families at their home country. Many consider them as additional or non-labor income, used for consumption and investment purposes. However, it seems that more and more recipients become heavily dependent on these remittances for their households needs. The presence of another source of income would give an individual less incentive to work and may cause him to choose leisure over labor. The aim of this study is to determine if remittances have an impact on the labor participation of households heads. From using the merged FIEs, LFS and SOW dataset of the Philippines and OLS regression models, it was concluded that remittances do impose less number of hours worked last week for the household heads that receive them from those that do not. It was also observed that results vary according to gender and the region where the household head reside
Identification of a conserved gene signature associated with an exacerbated inflammatory environment in the hippocampus of aging rats
High throughput screening for inhibitors of REST in neural derivatives of human embryonic stem cells reveals a chemical compound that promotes expression of neuronal genes
Decreased expression of neuronal genes such as brain-derived neurotrophic factor (BDNF) is associated with several neurological disorders. One molecular mechanism associated with Huntington disease (HD) is a discrete increase in the nuclear activity of the transcriptional repressor REST/NRSF binding to repressor element-1 (RE1) sequences. High-throughput screening of a library of 6,984 compounds with luciferase-assay measuring REST activity in neural derivatives of human embryonic stem cells led to identify two benzoimidazole-5-carboxamide derivatives that inhibited REST silencing in a RE1-dependent manner. The most potent compound, X5050, targeted REST degradation, but neither REST expression, RNA splicing nor binding to RE1 sequence. Differential transcriptomic analysis revealed the upregulation of neuronal genes targeted by REST in wild-type neural cells treated with X5050. This activity was confirmed in neural cells produced from human induced pluripotent stem cells derived from a HD patient. Acute intraventricular delivery of X5050 increased the expressions of BDNF and several other REST-regulated genes in the prefrontal cortex of mice with quinolinate-induced striatal lesions. This study demonstrates that the use of pluripotent stem cell derivatives can represent a crucial step toward the identification of pharmacological compounds with therapeutic potential in neurological affections involving decreased expression of neuronal genes associated to increased REST activity, such as Huntington disease
