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Objetivos: Apresentar as características gerais da DH e os principais desafios encarados no cotidiano pelos portadores. Método: foi realizada uma revisão de literatura na qual foram considerados artigos científicos embasados em banco de dados (PubMed, Scielo, Lilacs e diretório Google Acadêmico), artigos entre anos de 2007 a 2022, publicados em todos os idiomas, e aplicados os seguintes descritores: Huntington’s Disease Treatment; Genetics foram incluídos. Resultado: após a inclusão de 21 artigos utilizados, foi observado a significância de elevado índice mundial da DH, que acomete população em geral, porém há probabilidade que seja mais de herança paterna do que materna, devido à formação dos espermatozoides, principalmente quando se manifestam na fase juvenil de forma acelerada. Embora sejam desvendadas alternativas para terapia paliativa medicamentosa, há, também, a terapia física, o que auxilia a possibilidade de evolução na saúde desses indivíduos. Porém, prosseguem as pesquisas relacionadas às condutas melhores na qualidade de vida dessa população. Conclusão: Esta revisão evidencia a importância para doenças neurodegenerativas pouco vistas e comentadas, como a DH, mas que carece de esclarecimentos que auxiliem, com eficácia, tanto na recuperação, como no processo de habilidades da existência desses portadores com DH.

Background The administration of certain cannabinoids provides neuroprotection in models of neurodegenerative diseases by acting through various cellular and molecular mechanisms. Many cannabinoid actions in the nervous system are mediated by CB1 receptors, which can elicit psychotropic effects, but other targets devoid of psychotropic activity, including CB2 and nuclear PPARγ receptors, can also be the target of specific cannabinoids. Methods We investigated the pro-neurogenic potential of the synthetic cannabigerol derivative, VCE-003.2, in striatal neurodegeneration by using adeno-associated viral expression of mutant huntingtin in vivo and mouse embryonic stem cell differentiation in vitro. Results Oral administration of VCE-003.2 protected striatal medium spiny neurons from mutant huntingtin-induced damage, attenuated neuroinflammation and improved motor performance. VCE-003.2 bioavailability was characterized and the potential undesired side effects were evaluated by analyzing hepatotoxicity after chronic treatment. VCE-003.2 promoted subventricular zone progenitor mobilization, increased doublecortin-positive migrating neuroblasts towards the injured area, and enhanced effective neurogenesis. Moreover, we demonstrated the proneurogenic activity of VCE-003.2 in embryonic stem cells. VCE-003.2 was able to increase neuroblast formation and striatal-like CTIP2-mediated neurogenesis. Conclusions The cannabigerol derivative VCE-003.2 improves subventricular zone-derived neurogenesis in response to mutant huntingtin-induced neurodegeneration, and is neuroprotective by oral administration. Electronic supplementary material The online version of this article (10.1186/s40035-019-0148-x) contains supplementary material, which is available to authorized users.

Modifiers of Mendelian disorders can provide insights into disease mechanisms and guide therapeutic strategies. A recent genome-wide association (GWA) study discovered genetic modifiers of Huntington's disease (HD) onset in Europeans. Here, we performed whole genome sequencing and GWA analysis of a Venezuelan HD cluster whose families were crucial for the original mapping of the HD gene defect. The Venezuelan HD subjects develop motor symptoms earlier than their European counterparts, implying the potential for population-specific modifiers. The main Venezuelan HD family inherits HTT haplotype hap.03, which differs subtly at the sequence level from European HD hap.03, suggesting a different ancestral origin but not explaining the earlier age at onset in these Venezuelans. GWA analysis of the Venezuelan HD cluster suggests both population-specific and population-shared genetic modifiers. Genome-wide significant signals at 7p21.2–21.1 and suggestive association signals at 4p14 and 17q21.2 are evident only in Venezuelan HD, but genome-wide significant association signals at the established European chromosome 15 modifier locus are improved when Venezuelan HD data are included in the meta-analysis. Venezuelan-specific association signals on chromosome 7 center on SOSTDC1, which encodes a bone morphogenetic protein antagonist. The corresponding SNPs are associated with reduced expression of SOSTDC1 in non-Venezuelan tissue samples, suggesting that interaction of reduced SOSTDC1 expression with a population-specific genetic or environmental factor may be responsible for modification of HD onset in Venezuela. Detection of population-specific modification in Venezuelan HD supports the value of distinct disease populations in revealing novel aspects of a disease and population-relevant therapeutic strategies., Author summary Huntington’s disease (HD) is a dominantly inherited neurodegenerative disorder caused by a CAG trinucleotide expansion in HTT, which encodes huntingtin. HD involves various neurological manifestations such as involuntary movements, cognitive decline, and personality change; age at onset of diagnostic signs is partly determined by the length of the CAG repeat. However, genome-wide analysis of European HD subjects revealed that age at onset corrected for individual CAG repeat size is modified by other genetic factors, revealing potential disease-delaying pathways that form targets for therapeutic strategies. In this study, we set out to identify genetic modifiers in a Venezuelan HD cluster whose families were crucial for discovering the cause of HD. Through genome-wide association analysis using age at onset corrected for CAG repeat size as the phenotype, we found genome-wide significant (chromosome 7) and suggestive significant association signals (chromosomes 4 and 17). Significant modification signals in Venezuelan HD appear to be population-specific because genetic analysis of European HD subjects did not reveal modification signals at those locations. Nevertheless, established modification signals in European HD at a chromosome 15 locus were also augmented by Venezuelan HD data, supporting the existence of both shared and population-specific genetic modifiers in HD. Together with the full sequence of HTT shared by the majority of these Venezuelan HD subjects, our genetic analysis provides insights into the geographical origin of the founder mutation, meaningful allele-specific sites for gene targeting approaches, and potential targets for disease-modifying intervention in this population.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior A doença de Huntington (DH) é uma desordem neurodegenerativa autossômica causada por uma expansão de poliglutaminas ( > 35 repetições) na região amino-terminal da proteína huntingtina (htt). A htt possui a capacidade de se ligar a vários fatores de transcrição, como o CREB e o REST. Essas interações estão frequentemente alteradas na presença da huntingtina mutante (mhtt). Uma alteração importante nos mecanismos celulares promovida pela mhtt são as modificações da sinalização celular ativadas via receptor metabotrópico de glutamato do tipo 5 (mGluR5). O mGluR5 exerce um papel dinâmico no controle da expressão gênica, já que regula a atividade de vários fatores de transcrição. Logo, o objetivo desse estudo foi investigar as alterações na expressão de genes envolvidos na plasticidade sináptica promovidas pelo mGluR5 e pela proteína huntingtina mutante através do knockout do mGluR5 em um modelo murino da doença de Huntington, o BACHD. Nossos resultados demonstraram que os animais mGluR5 knockout apresentaram uma menor expressão de REST. Entretanto, a expressão dos alvos desse repressor gênico sofreram influência não só do mGluR5, mas também da mhtt, uma vez que os animais BACHD exibiram uma redução da expressão, enquanto que os animais mGluR5-/- e BACHD/mGluR5-/- um aumento. Além disso, vimos que a ativação do CREB e a expressão de seus alvos estavam reduzidas nos animais mGluR5 knockout, expressando ou a htt selvagem ou a mhtt. Nossos resultados também sugerem um comprometimento da plasticidade sináptica e do número de terminais sinápticos nos animais BACHD/mGluR5-/-, já que esses animais apresentaram uma diminuição da expressão de genes utilizados como marcadores dos terminais pré- e pós-sináptico, como a sintaxina e a PSD95, respectivamente. Como conclusão, esse trabalho demonstra a influência do mGluR5 e da mhtt na expressão de genes envolvidos na plasticidade sináptica. Também evidencia-se a interferência dominante do mGluR5 na expressão dos genes analisados, uma vez que o animal BACHD/mGluR5-/- segue o perfil de expressão da linhagem mGluR5-/-. Ademais, destaca-se o papel do mGluR5 na expressão de REST, algo que ainda não havia sido relatado. Logo, futuros experimentos serão necessários para elucidar os mecanismos subjacentes às alterações observadas nos camundongos BACHD/ mGluR5-/-. Huntington's disease (DH) is an autosomal dominant neurodegenerative disorder caused by a polyglutamine expansion (> 35 replicates) in the amino-terminal region of the huntingtin protein (htt). Htt has the ability to bind to various transcription factors, such as CREB and REST. However, these interactions are often disrupted in the presence of mutant huntingtin (mhtt). One major change in the cellular physiology triggered by mhtt is the alteration in cell signaling activated via the metabotropic glutamate receptor 5 (mGluR5). mGluR5 plays a dynamic role in the control of gene expression, as it regulates the activity of several transcription factors. Therefore, the aim of this study was to investigate the changes promoted by mGluR5 and mhtt in the expression of genes involved in synaptic plasticity by knocking out mGluR5 expression in a mouse model of HD, the BACHD. Our results demonstrated that mGluR5-/- mice exhibited a lower expression of REST, as compared to wild-type mice. However, expression of REST target genes was influenced not only by mGluR5 but also by mhtt, since BACHD animals exhibited a reduction in expression, whereas animals mGluR5-/- and BACHD/mGluR5-/- showed an increase. In addition, our data indicate that CREB activation and the expression of its target genes are reduced in mGluR5 knockout animals, expressing either wild-type or mhtt. Our results also suggest that there is impairment in synaptic plasticity and in the number of synaptic terminals in BACHD/mGluR5-/- animals, since these animals exhibited a decrease in the expression of genes that are used as pre- and postsynaptic markers, such as syntaxin and PSD95, respectively. In conclusion, this study demonstrates the influence of mGluR5 and mhtt on the expression of genes involved in synaptic plasticity. Morevoer, our data show a dominant interference of mGluR5 in the expression of the analyzed genes, since the BACHD/mGluR5-/- animal follows the same expression pattern as mGluR5-/-. Interestingly, the mGluR5 role in REST expression is a very important finding, as it is a novel finding. Therefore, future experiments will be needed to elucidate the mechanisms underlying the changes observed in BACHD/mGluR5-/- mice.