Efeitos da privação de sono sobre aspectos cognitivos e sua relação com níveis de BDNF

Abstract

Chronic sleep disorders are related to cognitive impairments and brain-derived neurotrophic factor (BDNF) alterations. However, the effects of acute sleep deprivation on BDNF levels and its relation with cognitive performance remains unknown. The objective was to investigate BDNF levels, cognitive performance and their relations in healthy subjects after acute sleep deprivation. In this study, nineteen sleep-deprived and twenty control subjects completed depression, anxiety and sleep quality questionnaires. Sleep deprived subjects spent a full night awake performing different playful activities to keep themselves awake. Attention, executive function and working memory (prefrontal cortex-dependent) were assessed with Stroop and Digit-span tests. Declarative memory (hippocampus-dependent) was assessed with Logical Memory test. Serum BDNF was measured by sandwich ELISA. Data were analyzed with independent samples T-test and curve estimation regressions. P<0.05 was deemed statistically significant. Our results show that the sleep-deprived group had higher BDNF levels and normal performance on attention, executive function and working memory. However, declarative memory was impaired. A sigmoidal relation between BDNF and Stroop Test scores was found, showing that the test performance was greater when the BDNF levels were at its peak. These data showed that increased BDNF could be related, at least in part, to the maintenance of normal prefrontal cognitive functions after sleep deprivation. This potential relation should be further investigated.