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Previous issue date: 2014-12-10 / Aging is a heterogeneous process resulting of biomarkers elicited by multiple factors, such as adverse environment.. A biomarker widely studied as a mediator of aging is the telomeres length. Telomeres are DNA-structures located at the ends of the cells with a protective function. Naturally, It tend to decrease with cell replication, however early life stress (ELS) may accelerate this process promoting premature vulnerability to chronic disease and cognitive decline. In addition, studies suggest that genetic variations such as Val66Met BDNF polymorphism constitute risk condition for memory decline, especially when interacting with aversive environmental conditions. OBJECTIVE: This thesis aimed to investigate the ELS, the Val66Met polymorphism and telomere length effects on the cognitive aging of women. METHOD: three sections are presented: the first, reviewed the neurobiological studies about the association between ELS and aging; the second, measured the telomere length of older women associated with ELS and cognitive decline and the third, examined the impact of the interaction between Val66Met BDNF polymorphism X ELS on the memory of older women. RESULTS: The first section identified neuroendocrine, immune, epigenetic and cell modifications signaling ELS as an accelerator of aging. The second, found no shorter telomeres in older women who reported ELS, but confirmed the association between telomere shortening and cognitive decline. Data from the third section confirmed the interaction between Val66Met BDNF polymorphism X ELS reduce memory performance of older women. The studies suggest telomere shortening as a biomarker of cognitive performance in women, but not directly mediated by ELS. Also, the interaction between the Val66Met BDNF polymorphism X ELS was confirmed as a significant risk condition for impairment in memory performance of older women. / O envelhecimento ? um processo heterog?nio resultante de marcadores biol?gicos desencadeados por m?ltiplos fatores, tais como ambientes adversos. Um biomarcador de envelhecimento ? o encurtamento dos tel?meros, estruturas protetoras do DNA localizadas nas suas termina??es que se reduzem com a replica??o celular. Estressores na inf?ncia podem promover uma acelera??o deste processo com manifesta??o precoce de doen?as cr?nicas e decl?nio cognitivo. Evidencia-se que a intera??o do estresse precoce X varia??es gen?ticas, como o polimorfismo Val66Met do BDNF, tamb?m se constituem em condi??o de risco para preju?zo da mem?ria no envelhecimento. OBJETIVO: investigar o impacto do estresse precoce, do polimorfismo Val66Met do BDNF e do tamanho do tel?mero no desempenho cognitivo de idosas. M?TODO: s?o apresentadas tr?s se??es: uma te?rica que revisou estudos neurobiol?gicos que investigaram a associa??o entre estresse precoce e envelhecimento e duas emp?ricas: a primeira, mensurou o tamanho do tel?mero de idosas relacionando com o estresse precoce e com desempenho cognitivo e a segunda avaliou a intera??o do polimorfismo Val66Met do BDNF X estresse precoce como fator de risco ao decl?nio mnem?nico de idosas. RESULTADOS: a se??o te?rica demonstrou evid?ncias neuroend?crinas, imunol?gicas, epigen?ticas e celulares que sinalizam o estresse precoce como acelerador do envelhecimento. A primeira se??o emp?rica n?o encontrou tel?meros mais curtos nas idosas que mencionaram estresse precoce, por?m confirmou associa??o entre o encurtamento de tel?mero e decl?nio cognitivo. Os dados da segunda se??o emp?rica confirmaram que a intera??o do polimorfismo Val66Met X estresse precoce prejudica a mem?ria. CONSIDERA??ES FINAIS: Refor?a-se o encurtamento telom?rico como biomarcador do desempenho cognitivo de idosas, por?m n?o diretamente mediado pelo estresse precoce e a intera??o do polimorfismo Val66Met X estresse precoce como condi??o de risco para preju?zo mnem?nico de idosas.
| Identifer | oai:union.ndltd.org:IBICT/oai:tede2.pucrs.br:tede/914 |
| Date | 10 December 2014 |
| Creators | De Nardi, Tatiana de Carvalho |
| Contributors | Grassi-Oliveira, Rodrigo |
| Publisher | Pontif?cia Universidade Cat?lica do Rio Grande do Sul, Programa de P?s-Gradua??o em Psicologia, PUCRS, BR, Faculdade de Psicologia |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | Unknown |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/doctoralThesis |
| Format | application/pdf |
| Source | reponame:Biblioteca Digital de Teses e Dissertações da PUC_RS, instname:Pontifícia Universidade Católica do Rio Grande do Sul, instacron:PUC_RS |
| Rights | info:eu-repo/semantics/openAccess |
| Relation | 2588426296948062698, 500, 600, 2599381623216554467 |
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