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Dementia & Neuropsychologia

Print version ISSN 1980-5764

Dement. neuropsychol. vol.5 no.1 São Paulo Jan./Mar. 2011

https://doi.org/10.1590/S1980-57642011DN05010003 

Views & reviews

Effects of stress hormones on the brain and cognition: Evidence from normal to pathological aging

Efeitos dos hormônios do estresse no cérebro e cognição: evidências do envelhecimento normal ao patológico

Juliana Nery de Souza-Talarico 1  

Marie-France Marin 2  

Shireen Sindi 3  

Sonia J. Lupien 4  

1PhD, Department of Medical-Surgical Nursing, School of Nursing, University of São Paulo, São Paulo SP, Brazil and Behavioral and Cognitive Neurology Unit, Department of Neurology, Faculty of Medicine, University of São Paulo, São Paulo SP, Brazil.

2MSc, Center for Studies on Human Stress, Mental Health Research Center Fernand-Seguin, Louis-H. Lafontaine Hospital, Université de Montreal, Canada.

3MSc, Department of Neurology and Neurosurgery, McGill University, Montreal, Canada.

4PhD, Center for Studies on Human Stress, Mental Health Research Center Fernand-Seguin, Louis-H. Lafontaine Hospital, Université de Montreal, Canada.


Abstract

Several studies have demonstrated a wide cognitive variability among aged individuals. One factor thought to be associated with this heterogeneity is exposure to chronic stress throughout life. Animal and human evidence demonstrates that glucocorticoids (GCs), the main class of stress hormones, are strongly linked to memory performance whereby elevated GC levels are associated with memory performance decline in both normal and pathological cognitive aging. Accordingly, it is believed that GCs may increase the brain's vulnerability to the effects of internal and external insults, and thus may play a role in the development of age-related cognitive disorders such as Alzheimer's disease (AD). The aim of this review article was to investigate the effects of GCs on normal and pathological cognitive aging by showing how these hormones interact with different brain structures involved in cognitive abilities, subsequently worsen memory performance, and increase the risk for developing dementia.

Key words: glucocorticoids; memory; aging; Alzheimer's disease

Resumo

Vários estudos têm demonstrado uma ampla variabilidade cognitiva entre indivíduos idosos. Um dos fatores que tem sido associado com esta heterogeneidade é a exposição crônica ao estresse ao longo da vida. Evidências em humanos em animais têm mostrado que os glicocorticóides (GCs), principal classe de hormônios do estresse, estão fortemente associados com o desempenho da memória, sendo que concentrações elevadas de GCs está correlacionada com declínio da memória no envelhecimento cognitivo normal e patológico. Consequentemente, alguns autores têm proposto que os GCs podem aumentar a vulnerabilidade do cérebro aos efeitos de insultos internos e externos desempenhando, portanto, papel importante no desenvolvimento de transtornos cognitivos associados à idade como a doença de Alzheimer (AD). Este artigo de revisão discute os efeitos dos GCs no envelhecimento cognitivo normal e patológico demonstrando como estes hormônios interagem com diferentes estruturas cerebrais envolvidas em habilidades cognitivas e subsequentemente pioram o desempenho da memória e aumentam o risco para o desenvolvimento de demência.

Palavras-chave: glicocorticóides; memória; envelhecimento; doença de Alzheimer

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Received: November 17, 2010; Accepted: February 14, 2011

Juliana Nery de Souza Talarico - Av. Dr. Enéas de Carvalho Aguiar, 419 - 05403-000 São Paulo SP - Brazil. E-mail: junery@usp.br

Disclosure: The authors report no conflits of interest

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