RESUMEN
BACKGROUND: Although Down syndrome (DS) is the most frequent human chromosomal disorder and it causes mainly intellectual disability, its clinical presentation is complex and variable. OBJECTIVE: We aimed to analyze and compare the transcriptome disruption in several brain areas from individuals with DS and euploid controls as a new approach to consider a global systemic differential disruption of gene expression beyond chromosome 21. METHODS: We used data from a DNA microarray experiment with ID GSE59630 previously deposited in the GEO DataSet of NCBI database. The array contained log2 values of 17,537 human genes expressed in several aeras of the human brain. We calculated the differential gene expression (Z-ratio) of all genes. RESULTS: We found several differences in gene expression along the DS brain transcriptome, not only in the genes located at chromosome 21 but in other chromosomes. Moreover, we registered the lowest Z-ratio correlation between the age ranks of 16-22 weeks of gestation and 39-42 years (R2 = 0.06) and the highest Z-ratio correlation between the age ranks of 30-39 years and 40-42 years (R2 = 0.89). The analysis per brain areas showed that the hippocampus and the cerebellar cortex had the most different gene expression pattern when compared to the brain as a whole. CONCLUSIONS: Our results support the hypothesis of a systemic imbalance of brain protein homeostasis, or proteostasis network of cognitive and neuroplasticity process, as new model to explain the important effect on the neurophenotype of trisomy that occur not only in the loci of chromosome 21 but also in genes located in other chromosomes.
Asunto(s)
Síndrome de Down , Encéfalo/metabolismo , Síndrome de Down/genética , Perfilación de la Expresión Génica/métodos , Humanos , Lactante , Transcriptoma/genética , TrisomíaRESUMEN
DNA methylation and histone posttranslational modifications are epigenetics processes that contribute to neurophenotype of Down Syndrome (DS). Previous reports present strong evidence that nonhistone high-mobility-group N proteins (HMGN) are epigenetic regulators. They play important functions in various process to maintain homeostasis in the brain. We aimed to analyze the differential expression of five human HMGN genes in some brain structures and age ranks from DS postmortem brain samples. Methodology: We performed a computational analysis of the expression of human HMGN from the data of a DNA microarray experiment (GEO database ID GSE59630). Using the transformed log2 data, we analyzed the differential expression of five HMGN genes in several brain areas associated with cognition in patients with DS. Moreover, using information from different genome databases, we explored the co-expression and protein interactions of HMNGs with the histones of nucleosome core particle and linker H1 histone. Results: We registered that HMGN1 and HMGN5 were significantly overexpressed in the hippocampus and areas of prefrontal cortex including DFC, OFC, and VFC of DS patients. Age-rank comparisons between euploid control and DS individuals showed that HMGN2 and HMGN4 were overexpressed in the DS brain at 16 to 22 gestation weeks. From the BioGRID database, we registered high interaction scores of HMGN2 and HMGN4 with Hist1H1A and Hist1H3A. Conclusions: Overall, our results give strong evidence to propose that DS would be an epigenetics-based aneuploidy. Remodeling brain chromatin by HMGN1 and HMGN5 would be an essential pathway in the modification of brain homeostasis in DS.
Asunto(s)
Cognición/fisiología , Síndrome de Down/genética , Proteínas HMGN/genética , Encéfalo/metabolismo , Mapeo Encefálico/métodos , Bases de Datos Genéticas , Síndrome de Down/metabolismo , Epigénesis Genética/genética , Expresión Génica/genética , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica/genética , Proteínas HMGN/metabolismo , Proteína HMGN1/genética , Proteína HMGN2/genética , Hipocampo/metabolismo , Humanos , Nucleosomas/genética , Corteza Prefrontal/metabolismo , Transactivadores/genética , Factores de Transcripción/genética , Transcriptoma/genéticaRESUMEN
Abstract Introduction: The high incidence of sports injuries in elite athletes is a concern in sports medicine. A broad vision of sport injuries in Colombia and its pathophysiology can be achieved in the scope of genomics, which could respond to numerous sports injuries from the Identification of single nucleotide polymorphism that lead to disabilities that affect the health of athletes and often distance them from the field of play. Objective: To determine the association of single nucleotide polymorphisms in various genes with sports injuries in soccer. Material and methods: We searched in the databases PubMed, ScienceDirect and EBSCO for studies published in the last 6 years to January 2020, including studies in English and Portuguese, corresponding to case-control clinical studies, where the experimental group were soccer practitioners and controls were supposedly healthy people. The final papers were assessed for quality and bias using the Jadad scoring scale or Oxford quality scoring system. From the data obtained, heterogeneity was identified with the I2 test and the Q statistic, for the estimation of the effect in the cohort studies the odds ratio and p value <0.05 were used, obtaining the forest plots of each gen. Results: 10 out of 1928 studies were selected, finding a degree of heterogeneity in all studies, such as the risk of injury to ACNT3 SNP (OR = 0.98, 95% CI 0.64-1.50), MMP (OR = 1.16, 95% CI 0.86 - 1.58, p = 0.33), TIMP2 (OR 1.03 95% CI 0.65-1.63), VEFGA (OR 0.98 95% CI 0.70-1.37). Conclusion: The studies showed moderate heterogeneity with statistical significance for the ACTN3 and TIM SNPs, providing a pathway for future studies that relate to sports injuries. MÉD.UIS.2021;34(3): 9-18.
Resumen Introducción: La alta incidencia de lesiones deportivas en atletas de élite es una preocupación en medicina deportiva. Se puede lograr una visión amplia sobre las lesiones deportivas en Colombia y sobre su fisiopatología desde el ámbito de la genómica, la cual podría responder a numerosas lesiones deportivas a partir de la Identificación de polimorfismos de nucleótido único que conducen a discapacidades que afectan la salud de los deportistas y frecuentemente los distancian del campo de juego. Objetivo: Determinar la asociación entre polimorfismos de nucleótido único en varios genes con lesiones deportivas en el fútbol. Materiales y métodos: Se realizó búsqueda en las bases de datos PubMed, ScienceDirect y EBSCO de estudios publicados en los últimos 6 años hasta enero de 2020, incluyendo estudios en inglés y portugués, correspondientes a estudios clínicos de casos y controles, donde el grupo experimental fueran practicantes de fútbol y los controles fueran personas presumiblemente saludables. Se evaluó la calidad y el sesgo de los artículos finales mediante la escala de puntuación de Jadad o el sistema de puntuación de calidad de Oxford. A partir de los datos obtenidos se identificó la heterogeneidad con la prueba de I2 y el estadístico Q, para la estimación del efecto en los estudios de cohorte se utilizaron odds ratio y valor p <0.05, obteniendo los forest plot de cada gen. Resultados. 10 de los 1928 estudios fueron seleccionados, se encontró un grado de heterogeneidad en todos los estudios, como el riesgo de lesión de los polimorfismos de nucleótido único para ACNT3 (OR = 0,98; IC del 95%: 0.64-1.50), MMP (OR = 1.16; IC del 95%: 0.86-1.58, p = 0.33), TIMP2 (OR = 1,03; IC del 95%: 0,65-1,63), VEFGA (OR = 0,98; IC del 95%: 0,70-1,37). Conclusión. Los estudios mostraron una heterogeneidad moderada con significancia estadística para los polimorfismos de nucleótido único de ACTN3 y TIM, lo que proporciona una vía para futuros estudios en relación con lesiones deportivas. MÉD.UIS.2021;34(3): 9-18.
Asunto(s)
Humanos , Fútbol , Polimorfismo Genético , Heridas y Lesiones , Metaloproteinasas de la MatrizRESUMEN
Uno de los retos más importantes de este siglo en la neurología genómica es construir mapas de expresión espacial de genes a lo largo de las distintas estructuras cerebrales con el fin de correlacionarlos con ciertas neuropatologías. Se analizaron los perfiles de transcripción de ocho genes HAS21 localizados en la región crítica del síndrome de Down en diferentes estructuras del cerebro humano normal. Se tomaron como referencia los valores de expresión de ocho genes HAS21/DSCR provenientes de experimentos de micromatrices de ADN de cerebros humanos normales y cuyos valores están disponibles en la base de datos del proyecto cerebro humano del Atlas del Cerebro del Allen Institute for Brain Sciences en Seattle, Washington (http://www.brainmap.org). Se determinó una expresión diferencial de estos genes HAS21/DSCR a lo largo de las estructuras localizadas en el lóbulo frontal, el lóbulo límbico y en los núcleos centrales. En el putamen, el núcleo caudado, el giro parahipocampal y en las áreas centrales se registraron los mayores niveles de transcripción global; estas áreas del cerebro parecen estar asociadas con diversos procesos de aprendizaje y de memoria. Se correlacionó la transcripción diferencial de genes DSCR con la localización cerebral y su potencial papel funcional.
One of the most important challenges of the 21st Century Neurology is to build gene expression profiles along the different structures of human brain trying to correlate them with some neuropathologies. The expression profiles of eight HAS21 genes located on the Down syndrome critical region in different structures of the normal human brain was analyzed. From DNA microarray experiments of normal human brains which are available in the free access human brain database of the Brain Atlas project of the Allen Institute for Brain Sciences in Seattle, Washington (http://www.brainmap.org) expression levels data of eight HSA21/DSCR genes along different structures of normal human brain were statistically analyzed. A differential expression of these genes HSA21/DSCR in some anatomic structures located in the frontal lobe, limbic lobe and cerebral central nuclei was registered. Putamen, caudate nucleus, parahipocampal gyro and central areas, showed high levels of transcription for those HSA21/DSCR genes included in the study; these areas of the brain appear to be associated with some processes of learning and memory. This study allowed us to correlate the differential transcription of DSCR genes, their structural localization and functional role in brain function.
Um dos maiores desafio deste século na neurologia genômica é construir mapas de expressão espacial de genes ao longo das diferentes estruturas cerebrais com o fim de correlacionálos com certas neuropatologias. Foram analisados os perfis de transcrição de oito genes HAS21 localizados na região crítica da síndrome de Down em diferentes estruturas do cérebro humano normal. Foram usados como referência os valores de expressão de oito genes HAS21/DSCR provenientes de experimentos de micromatrizes de ADN de cérebros humanos normais e cujos valores estão disponíveis no bando de dados do projeto cérebro humano do Atlas do Cérebro do Allen Institute for Brain Sciences em Seattle, Washington (http://www.brainmap.org). Determinouse uma expressão diferencial destes genes HAS21/DSCR ao longo das estruturas localizadas no lóbulo frontal, o lóbulo límbico e nos núcleos centrais. No putâmen, o núcleo caudado, o giro parahipocampal e nas áreas centrais foram registrados os maiores níveis de transcrição global; estas áreas do cérebro parecem estar associadas com diversos processos de aprendizagem e de memória. Correlacionouse a transcrição diferencial de genes DSCR com a localização cerebral e seu potencial papel funcional.
