Neurotrophins and gender difference.

摘要

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family (NT) and is most expressed in central and peripheral nervous system, particularly in hippocampus, cerebral cortex (especially in temporal and occipital area, insula, motor and sensitive cortex) and amygdala [1]. The most part of evidence from animal studies suggests that BDNF influences serotonergic neurotransmission and vice versa [2], so several authors attributed interactions between BDNF and serotonin importance for the pathophysiology of mood disorders [3]. BDNF has been associated with metabolic processes and disease states. Its elevations have been linked to exercise in both animals and humans [4], while its reductions have been implicated in Alzheimer's disease [5], Hunting-ton's disease [6], schizophrenia [7], and depression [8]. Since then many studies investigated the various sites of BDNF production in humans, in both neuronal and non-neuronal cells [9]. BDNF is in present in human plasma and, since platelets represent a major storage site of BDNF in peripheral blood, serum levels are higher than plasma levels. It has been shown that plasma concentrations decrease significantly with age or weight gain, whereas platelet or serum levels do not seem to be altered [10]. Modifications in platelet BDNF have been reported in women throughout the menstrual cycle: studies have shown higher levels during the luteal phase than in the follicular phase [10]. Currently, gonadal steroids are considered modulating factors of sex differences in susceptibility to stress [11]. In experimental studies on hippocampal neurons, estrogen treatments displayed a sort of neuroprotective effect through their positive regulation of BDNF , and progesterone was found to amplify this effect [12].