Glucocorticoids and brain functions

Natural glucocorticoids are essential components of the body neuroendocrine system, modulating the physiological homeostasis and coordinating the adaptive responses to stressors. The complex activity of glucocorticoids involves almost all organs and tissues, including brain. Their effects on central nervous system vary with species, gender, age, hormone concentrations, timing, and duration of exposure. In humans, the glucocorticoid effects on brain functions entail influences on arousal, sleep, behaviour, cognition, memory, mood and affect. Two types of cytoplasmic receptors, namely mineralcorticoid and glucocorticoid receptors, having different brain distribution and functional pattern, mediate the hormonal activity through the stimulation or suppression of target gene transcription, depending on cell type. Synthetic glucocorticoids substantially share the same mechanisms of action, however, with different kinetics and/or receptor affinities In this paper, the main effects of glucocorticoids on brain functions are reviewed and discussed.