Sex steroids and cognitive function.
ABSTRACT Gonadal hormones, most notably oestradiol, enhance some aspects of cognitive function in animal and human models. However, the demonstrated effects are often not large and inconsistent across studies. Nonetheless, because increased numbers of women are living longer in a state of oestrogen deprivation, research on this topic continues to be important. This review traces major developments concerning hormonal influences on cognition and provides some insights from recent studies that may be fruitful for future research.
Article: Ecdysone signaling regulates the formation of long-term courtship memory in adult Drosophila melanogaster.[show abstract] [hide abstract]
ABSTRACT: Improved survival is likely linked to the ability to generate stable memories of significant experiences. Considerable evidence in humans and mammalian model animals shows that steroid hormones, which are released in response to emotionally arousing experiences, have an important role in the consolidation of memories of such events. In insects, ecdysone is the major steroid hormone, and it is well characterized with respect to its essential role in coordinating developmental transitions such as larval molting and metamorphosis. However, the functions of ecdysone in adult physiology remain largely elusive. Here, we show that 20-hydroxyecdysone (20E), the active metabolite of ecdysone that is induced by environmental stimuli in adult Drosophila, has an important role in the formation of long-term memory (LTM). In male flies, the levels of 20E were found to be significantly increased after courtship conditioning, and exogenous administration of 20E either enhanced or suppressed courtship LTM, depending on the timing of its administration. We also found that mutants in which ecdysone signaling is reduced were defective in LTM, and that an elevation of 20E levels was associated with activation of the cAMP response element binding protein (CREB), an essential regulator of LTM formation. Our results demonstrate that the molting steroid hormone ecdysone in adult Drosophila is critical to the evolutionarily conserved strategy that is used for the formation of stable memories. We propose that ecdysone is able to consolidate memories possibly by recapturing molecular and cellular processes that are used for normal neural development.Proceedings of the National Academy of Sciences 05/2009; 106(15):6381-6. · 9.68 Impact Factor
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ABSTRACT: The classic female estrogen, 17β-estradiol (E2), has been repeatedly shown to affect the perceptual processing of visual cues. Although gonadal E2 has often been thought to influence these processes, the possibility that central visual processing may be modulated by brain-generated hormone has not been explored. Here we show that estrogen-associated circuits are highly prevalent in the mouse primary visual cortex (V1). Specifically, we cloned aromatase, a marker for estrogen-producing neurons, and the classic estrogen receptors (ERs) ERα and ERβ, as markers for estrogen-responsive neurons, and conducted a detailed expression analysis via in-situ hybridization. We found that both monocular and binocular V1 are highly enriched in aromatase- and ER-positive neurons, indicating that V1 is a site of production and sensitivity to estrogens. Using double-fluorescence in-situ hybridization, we reveal the neurochemical identity of estrogen-producing and -sensitive cells in V1, and demonstrate that they constitute a heterogeneous neuronal population. We further show that visual experience engages a large population of aromatase-positive neurons and, to a lesser extent, ER-expressing neurons, suggesting that E2 levels may be locally regulated by visual input in V1. Interestingly, acute episodes of visual experience do not affect the density or distribution of estrogen-associated circuits. Finally, we show that adult mice dark-reared from birth also exhibit normal distribution of aromatase and ERs throughout V1, suggesting that the implementation and maintenance of estrogen-associated circuits is independent of visual experience. Our findings demonstrate that the adult V1 is a site of production and sensitivity to estrogens, and suggest that locally-produced E2 may shape visual cortical processing.PLoS ONE 01/2011; 6(5):e20400. · 4.09 Impact Factor
Chapter: Estrogen Influences on Cognition01/2012; , ISBN: 978-953-307-857-1