Análise da função de receptores da imunidade inata no desenvolvimento da esclerose lateral amiotrófica experimental
Data
2021-10-25
Autores
Silva, Denise Correia [UNIFESP]
Orientadores
Barboza, Renato [UNIFESP]
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
A neuroinflamação é um processo que desempenha papel importante na progressão de doenças neurodegenerativas como a Esclerose Lateral Amiotrófica (ELA), que é caracterizada pela morte de neurônios motores e progressiva paralisia muscular. Dados da literatura têm mostrado que mutações observadas na doença, levam à má formação de proteínas, como a Superóxido Dismutase 1 (SOD1), que pode servir como fator desencadeador do processo neuroinflamatório. Este processo é mediado pela ativação de receptores da imunidade inata, como os receptores tipo Toll (TLR) e os receptores tipo Nod (NLR); estes que são capazes de formar complexos proteicos, conhecidos como Inflamassomas. É de grande importância o entendimento desses processos, visto que, os mecanismos da neuroinflamação na ELA ainda não foram totalmente esclarecidos. Nesse sentido, o objetivo central deste trabalho foi analisar a função dos TLRs e Inflamassomas (NLRP1, NLRP3 e AIM2) no curso da doença. Além disso, avaliamos o efeito do Parthenolide, um sesquiterpeno lactano derivado da Tanacetum parthenium, que possui reconhecida atividade anti-inflamatória sobre vias de ativação relacionadas aos receptores da imunidade inata. Para estes fins, utilizamos um modelo murino de ELA, com camundongos transgênicos para a proteína SOD1 humana constitutiva ou mutante SOD1G93A. Obtivemos amostras da medula espinhal destes animais, com 120 e 140 dias de vida, período em que os sinais característicos da doença se tornam evidentes. Após, avaliamos a expressão de marcadores envolvidos nestes processos. Os resultados sugerem aumento de mRNAs para os receptores NLRP1, NLRP3 e os TLR2 e 4; na medula espinhal dos camundongos SOD1 mutantes, em relação aos controles. Bem como, maior presença de proteínas pró-inflamatórias nos tecidos desses animais. Além disso, os dados sugerem a diminuição dos níveis destes mRNAs para o gene NLRP3 na medula espinhal dos camundongos SOD1 mutantes tratados com Parthenolide, em relação aos SOD1 mutantes não tratados. Espera-se que os resultados deste trabalho possam auxiliar no entendimento dos mecanismos inflamatórios mediados por receptores da imunidade inata, que estão envolvidos com os processos de neurodegeneração.
Neuroinflammation is a process that plays an important role in the progression of neurodegenerative diseases such as Amyotrophic Lateral Sclerosis (ALS), which is characterized by the death of motor neurons and progressive muscle paralysis. Scientific data have shown that mutations observed in the disease lead to the malformation of proteins, such as Superoxide Dismutase 1 (SOD-1), which can serve as a triggering factor for the neuroinflammatory process. This process is mediated by the activation of innate immunity receptors, such as Toll-like receptors (TLR) and Nod-like receptors (NLR); these can form protein complexes, known as Inflammasomes. It is very important to understand these processes since the mechanisms of neuroinflammation in ALS have not been fully clarified. In this sense, the main objective of this work was to analyze the role of TLRs and Inflammasomes (NLRP1, NLRP3 e AIM2)te in the course of the disease. In addition, we evaluated the effect of Parthenolide, a lactam sesquiterpene derived from Tanacetum parthenium, which has recognized anti-inflammatory activity on activation pathways related to innate immunity receptors. For these purposes, we used a murine model of ALS, with mice transgenic for the constitutive human SOD1 protein or SOD1 mutant (G93A). We obtained samples from the spinal cord of these animals, at 120 and 140 days of life, a period in which the characteristic signs of the disease become evident. Afterwards, we evaluated the expression of markers involved in these processes. The results suggest an increase in mRNAs for NLRP1, NLRP3 and TLR2 and 4 receptors; in the spinal cord of SOD1G93A mice, compared to controls. As well as greater presence of pro-inflammatory proteins in mutant tissues. In addition, the data suggest a trend towards decreased levels of these mRNAs in the spinal cord of SOD1 mutant mice treated with Parthenolide, compared to untreated SOD1G93A. It is expected that the results of this work may help to understand the inflammatory mechanisms mediated by innate immunity receptors, which are involved in neurodegeneration processes.
Neuroinflammation is a process that plays an important role in the progression of neurodegenerative diseases such as Amyotrophic Lateral Sclerosis (ALS), which is characterized by the death of motor neurons and progressive muscle paralysis. Scientific data have shown that mutations observed in the disease lead to the malformation of proteins, such as Superoxide Dismutase 1 (SOD-1), which can serve as a triggering factor for the neuroinflammatory process. This process is mediated by the activation of innate immunity receptors, such as Toll-like receptors (TLR) and Nod-like receptors (NLR); these can form protein complexes, known as Inflammasomes. It is very important to understand these processes since the mechanisms of neuroinflammation in ALS have not been fully clarified. In this sense, the main objective of this work was to analyze the role of TLRs and Inflammasomes (NLRP1, NLRP3 e AIM2)te in the course of the disease. In addition, we evaluated the effect of Parthenolide, a lactam sesquiterpene derived from Tanacetum parthenium, which has recognized anti-inflammatory activity on activation pathways related to innate immunity receptors. For these purposes, we used a murine model of ALS, with mice transgenic for the constitutive human SOD1 protein or SOD1 mutant (G93A). We obtained samples from the spinal cord of these animals, at 120 and 140 days of life, a period in which the characteristic signs of the disease become evident. Afterwards, we evaluated the expression of markers involved in these processes. The results suggest an increase in mRNAs for NLRP1, NLRP3 and TLR2 and 4 receptors; in the spinal cord of SOD1G93A mice, compared to controls. As well as greater presence of pro-inflammatory proteins in mutant tissues. In addition, the data suggest a trend towards decreased levels of these mRNAs in the spinal cord of SOD1 mutant mice treated with Parthenolide, compared to untreated SOD1G93A. It is expected that the results of this work may help to understand the inflammatory mechanisms mediated by innate immunity receptors, which are involved in neurodegeneration processes.