Estrogens and the heart. Do they help or hurt? How estrogen impacts the cardiovascular system

Extensive epidemiological observations, clinical mechanistic studies, and basic laboratory research have suggested that the incidence of Cardiovascular Disease (CVD) increases with menopause and that Hormone Replacement Therapy (HRT), or more specifically Estrogen Replacement Therapy (ERT), is associated with beneficial cardiovascular effects in postmenopausal women. Estrogen has a multitude of biological effects that may account for its apparent cardiovascular protection, including favourable effects on the lipid profile, antioxidant activity, enhanced fibrinolysis, and a series of actions on the vasculature. However, because estrogen affects so many cellular processes, it is imperative to gain a better understanding of the molecular mechanisms, both genomic and non-genomic, by which estrogen induces cellular signals and modulates vascular responses. While there is no question that HRT effectively mitigates troublesome menopause symptoms, conflicting evidence about other effects of HRT has fuelled controversy concerning its relative benefits and risks. Moreover, it could seem that CVD protection mediated by replacement therapy is maximum when the therapy was initiated in the absence of signs of atherosclerosis (typically in premenopause) while it vanishes as atherosclerosis proceeds (in the postmenopausal patient). In addition, many questions remain regarding the effectiveness of type of hormonal compounds, doses, regimens, route and, mainly, on time of administration. There are data from recent literature that early menopause and not menopause per se, is a risk factor for CVD and that early ERT may have a role on delaying the atherosclerosis process in postmenopausal women. We conclude that is not time yet to close the chapter of the role of estrogens in the postmenopausal research, in fact, in this area has begun again.