Annals of the New York Academy of Sciences
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Ann. N. Y. Acad. Sci. · Jan 2007
A new transcript splice variant of the human glucocorticoid receptor: identification and tissue distribution of hGR Delta 313-338, an alternative exon 2 transactivation domain isoform.
All human glucocorticoid receptor (hGR) isoforms are encoded by the NR3C1 gene consisting of seven core exons (exons 2-8) common to all protein isoforms. The gene has two major exon 8-9 splice variants and a 5'-UTR consisting of 11 alternative splice variants. The N-terminal region of the hGR includes a tau 1 transactivation domain that interacts with proteins in the basal transcriptional apparatus, including the TATA box-binding protein. ⋯ Interestingly, the deleted residues show a number of potential phosphorylation sites including serine 317, known to be phosphorylated. It is thought that phosphorylation plays an important role in transactivation action of hGR. Thus, we hypothesize that hGRDelta313-338 represents a hGR isoform with an altered glucocorticoid-induced transactivation profile.
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Ann. N. Y. Acad. Sci. · Dec 2006
ReviewHormone replacement therapy and cardioprotection: what is good and what is bad for the cardiovascular system?
The incidence of cardiovascular diseases (CVDs) increases after menopause and at any age postmenopausal women have a significantly higher incidence of CVD compared to premenopausal women. Several epidemiological findings suggest the causative pathogenetic role of ovarian hormone deficiency in the development of CVD in women. Ovarian hormones have several potential protective effects on the cardiovascular system and despite several observational studies have shown the beneficial effect of estrogens and estrogen/progestin associations on CVD, at the present, after the findings of randomized studies, the effect of hormone replacement therapy (HRT) in the prevention of CVD is still under debate. ⋯ In early postmenopausal women, like the ones included in the observational studies, ovarian hormone replacement may be cardioprotective because of the responsiveness of the endothelium to estrogens that also buffer the detrimental effects upon coagulation. In late postmenopausal women ovarian hormones have either a null effect or even a detrimental effect because of the predominance of the procoagulant or plaque-destabilizing effects over the vasoprotective effects. Therefore, HRT has beneficial cardiovascular effects in younger women while it may have detrimental effect on coagulative balance and vascular inflammation and has little effect on cardiovascular functions in older women.
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During adolescence the brain shows remarkable changes in both structure and function. The plasticity exhibited by the brain during this pubertal period may make individuals more vulnerable to perturbations, such as stress. Although much is known about how exposure to stress and stress hormones during perinatal development and adulthood affect the structure and function of the brain, relatively little is known about how the pubertal brain responds to stress. ⋯ The purpose of this review is to present what is currently known about the pubertal maturation of the hypothalamic-pituitary-adrenal (HPA) axis, the neuroendocrine axis that mediates the stress response, and discuss what is currently known about how stressors affect the adolescent brain. Our dearth of knowledge regarding the effects of stress on the pubertal brain will be discussed in the context of our accumulating knowledge regarding stress-induced neuronal remodeling in the adult. Finally, as the adolescent brain is capable of such profound plasticity during this developmental stage, we will also explore the possibility of adolescence as a period of interventions and opportunities to mitigate negative consequences from earlier developmental insults.
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The major disease processes affecting the aorta are aortic aneurysms and dissections. Aneurysms are usually described in terms of their anatomic location, with thoracic aortic aneurysms (TAAs) involving the ascending and descending aorta in the thoracic cavity and abdominal aortic aneurysms (AAAs) involving the infrarenal abdominal aorta. ⋯ These similarities and differences between thoracic and abdominal aortas provide the basis for the various pathologic mechanisms observed in this disease. This review focuses on the comparison of the pathologic mechanisms involved in TAA and AAA.
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Ann. N. Y. Acad. Sci. · Nov 2006
ReviewObesity-related sleepiness and fatigue: the role of the stress system and cytokines.
Obesity has epidemic proportions in Western societies and, because of its significant association with morbidity and mortality, is a major public health issue. Excessive daytime sleepiness (EDS) and fatigue (tiredness without increased sleep propensity)--which have been associated with obesity--have a significant impact on individual well-being and public safety. In this article, we review data that challenge the belief that sleep apnea and sleep disruption per se are the primary determinants of obesity-related daytime sleepiness and fatigue. ⋯ On the basis of these data, we propose that obesity-related objective daytime sleepiness and fatigue are associated primarily with metabolic and psychological factors and less with sleep apnea and sleep disruption per se. Furthermore, we suggest that objective sleepiness is primarily related to metabolic factors, whereas fatigue appears to be related to psychological distress. Finally, based on data from studies in normal controls and patients with sleep disorders, we propose that the interaction of the hypothalamic-pituitary-adrenal (HPA) axis and proinflammatory cytokines determines the level of sleep/arousal within the 24-h cycle, that is, "hypercortisolemia" plus hypercytokinemia is associated with low sleep efficiency and fatigue, whereas "eucortisolemia" or "hypocortisolemia" plus hypercytokinemia is associated with high sleep efficiency and objective sleepiness.