Investigação da expressão de miRNAs em espermatozoides de pais de pacientes com transtorno do espectro autista (TEA)
Arquivos
Data
2023-01-17
Autores
Pereira, Marina Beninelli 
Orientadores
Teixeira, Taiza Stumpp
Tipo
Trabalho de conclusão de curso
Título da Revista
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Resumo
O transtorno do espectro autista (TEA) refere-se a um grupo de transtornos do neurodesenvolvimento com um amplo espectro de fenótipos clínicos, caracterizado principalmente por déficits de interação social, comportamentos repetitivos/estereotipados, problemas na percepção, interpretação e elaboração de comunicação verbal e não verbal, além de pouco ou nenhum contato visual. A maior parte das causas conhecidas é genética, porém somente as alterações genéticas não conseguem explicar todos os diversos casos dentro do espectro, tornando importante também a análise das influências ambientais e de fatores epigenéticos. Os miRNAs fazem parte dos mecanismos epigenéticos de controle da expressão gênica, sendo um tipo de sncRNA que atua em RNAm-alvo causando a inibição ou degradação deste. As marcas epigenéticas podem ser transmitidas a gerações seguintes através dos espermatozoides, que apesar do citoplasma escasso, transferem ao embrião grande quantidade de RNAs. O objetivo desta pesquisa é investigar a expressão e associações dos miRNAs tanto in silico a partir de bases de dados já existentes com os miRNAs alvos, quanto em espermatozoides de pais de pacientes TEA buscando relacionar os dados com aqueles obtidos a partir de células sanguíneas e neurônios (derivados in vitro) desses pacientes em dois outros estudos paralelos de nosso grupo. Para isto, foram realizadas análises bioinformáticas em uma série de plataformas para investigar os genes regulados por estes miRNA e as vias biológicas envolvidas, buscando possíveis associações com neurodesenvolvimento celular e TEA. Além disso, pais de pacientes TEA incluídos no estudo mais amplo que está em andamento em nosso grupo foram recrutados. O sêmen desses pais foi colhido, os espermatozoides purificados e submetidos à extração de RNA total e miRNA, para análise posterior da sua expressão por RT-qPCR. As análises bioinformáticas demonstraram forte relação dos miRNAs analisados com genes e as vias biológicas envolvidas com o TEA e o neurodesenvolvimento celular, indicando a influência que a expressão alterada destes miRNAs podem causar nestas vias de interesse. A análise da expressão dos miRNAs dos participantes da pesquisa será finalizada em um projeto posterior, devido a intercorrências no período de realização. Este estudo poderá contribuir para investigações futuras sobre herança epigenética paterna do TEA.
Autism Spectrum Disorder (ASD) refers to a group of neurodevelopmental disorders with a broad spectrum of clinical phenotypes, characterized by deficits in social interaction, repetitive/stereotyped behaviors, problems in perception, interpretation and elaboration of verbal and nonverbal communication and little or no eye contact. Such symptoms may be noticed in the first months of life, varying in intensity. So far, ASD diagnosis has been based in genetic analysis; however, genetics by itself cannot explain all the cases within the spectrum, making environmental influences and epigenetic analysis important aspects of ASD diagnosis. Epigenetics involves chemical and heritable modifications of gene expression without altering the DNA nucleotide base sequence. Epigenetic mechanisms are: DNA methylation, histone modification and regulation of gene expression by sncRNAs. Alterations of miRNA expression have been reported in ASD patients. Epigenetic marks can be transmitted to other generations through the sperm, which despite the scarce cytoplasm, transfer large amounts of RNAs to the embryo. This research aims to investigate the expression and associations of miRNAs both in silico from existing databases with the target miRNAs, and in sperm from ASD patients’ fathers and relate the data obtained with those obtained from somatic tissues (blood cells and in vitro derived neurons) from these patients in two other parallel ongoing studies of our group. For this, bioinformatic analyzes were carried out on a series of platforms to investigate the genes regulated by these miRNAs and the biological pathways involved, seeking possible associations with cellular neurodevelopment and ASD. In addition, ASD patients’ fathers included in the wider ongoing study of our group were recruited. These fathers’ semen was collected, the spermatozoa purified and subjected to total RNA and miRNA extraction, for later analysis of their expression by RT-qPCR. The bioinformatic analyzes showed a strong relationship between the analyzed miRNAs and genes as well as the biological pathways involved with ASD and cell neurodevelopment, indicating the influence that the altered expression of these miRNAs can cause in these pathways of interest. Due to unexpected intercurrences during the period, the miRNAs expression analysis will be performed later. This study can contribute to the future investigations about paternal epigenetic inheritance of ASD.
Autism Spectrum Disorder (ASD) refers to a group of neurodevelopmental disorders with a broad spectrum of clinical phenotypes, characterized by deficits in social interaction, repetitive/stereotyped behaviors, problems in perception, interpretation and elaboration of verbal and nonverbal communication and little or no eye contact. Such symptoms may be noticed in the first months of life, varying in intensity. So far, ASD diagnosis has been based in genetic analysis; however, genetics by itself cannot explain all the cases within the spectrum, making environmental influences and epigenetic analysis important aspects of ASD diagnosis. Epigenetics involves chemical and heritable modifications of gene expression without altering the DNA nucleotide base sequence. Epigenetic mechanisms are: DNA methylation, histone modification and regulation of gene expression by sncRNAs. Alterations of miRNA expression have been reported in ASD patients. Epigenetic marks can be transmitted to other generations through the sperm, which despite the scarce cytoplasm, transfer large amounts of RNAs to the embryo. This research aims to investigate the expression and associations of miRNAs both in silico from existing databases with the target miRNAs, and in sperm from ASD patients’ fathers and relate the data obtained with those obtained from somatic tissues (blood cells and in vitro derived neurons) from these patients in two other parallel ongoing studies of our group. For this, bioinformatic analyzes were carried out on a series of platforms to investigate the genes regulated by these miRNAs and the biological pathways involved, seeking possible associations with cellular neurodevelopment and ASD. In addition, ASD patients’ fathers included in the wider ongoing study of our group were recruited. These fathers’ semen was collected, the spermatozoa purified and subjected to total RNA and miRNA extraction, for later analysis of their expression by RT-qPCR. The bioinformatic analyzes showed a strong relationship between the analyzed miRNAs and genes as well as the biological pathways involved with ASD and cell neurodevelopment, indicating the influence that the altered expression of these miRNAs can cause in these pathways of interest. Due to unexpected intercurrences during the period, the miRNAs expression analysis will be performed later. This study can contribute to the future investigations about paternal epigenetic inheritance of ASD.