Striatin-Dependent Membrane Estrogen Receptor Signaling and Vasoprotection by Estrogens

BakerIDI Heart & Diabetes Institute, PO Box 6492 St Kilda Road Central, Melbourne, Victoria 8008, Australia. .
Circulation (Impact Factor: 14.43). 09/2012; 126(16):1941-3. DOI: 10.1161/CIRCULATIONAHA.112.138958
Source: PubMed


It is well known that cardiovascular disease is less frequent in premenopausal women compared with men but rises rapidly in postmenopausal women. Such early observations led to the hypothesis that estrogen therapy will reduce the risk of postmenopausal women developing cardiovascular disease.(1) However, observational studies have led to conflicting results with some studies reporting reductions in cardiovascular disease in postmenopausal women taking estrogens whilst others observed no beneficial effects.(2) Rather increases in the risk of coronary heart disease and stroke have been reported, particularly for women who are older and those with a long hormone-free interval.(3) Such findings have led to the speculation that estrogens have competing cardiovascular effects-beneficial and detrimental and this has intensified efforts to better understand the range of cardiovascular effects mediated by estrogens and their signaling mechanisms, the ultimate aim being to develop new therapies for women that exert the beneficial effects of estrogen whilst minimizing potentially harmful effects. To achieve this aim, new studies to better understand both nuclear and membrane estrogen receptor (ER)-mediated signaling in target tissues such as the heart and blood vessels, immune cells and other target tissues are in progress. In this issue of Circulation, Moens and colleagues provide novel insights on the importance of membrane ER-mediated signaling pathways in blood vessels for vasoprotection and vascular gene regulation.(4).

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    • "In males, the ACE/AngII/AGTR1 pathways are enhanced, whereas, in females, the balance is shifted towards the ACE2/Ang(1-7)/MasR (Mas receptor) and angiotensin type 2 receptor (AT2R) pathways [79]. Studies reported that premenopausal women, as compared to age matched men, are protected from renal and cardiovascular disease, and this differential balance of the RAS between the sexes likely contributes [80, 81]. "
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