Both estrogen receptor subtypes, alpha and beta, attenuate cardiovascular remodeling in aldosterone salt-treated rats.; ; et al in Hypertension (2007), 50(2), 432-8 Experimental and population-based studies indicate that female gender and estrogens protect the cardiovascular system against aldosterone-induced injury. Understanding the function of estrogens in heart ... [more ▼] Experimental and population-based studies indicate that female gender and estrogens protect the cardiovascular system against aldosterone-induced injury. Understanding the function of estrogens in heart disease requires more precise information on the role of both estrogen receptor (ER) subtypes, ERalpha and ERbeta. Therefore, we determined whether selective activation of ERalpha or of ERbeta would confer redundant, specific, or opposing effects on cardiovascular remodeling in aldosterone salt-treated rats. The ERalpha agonist 16alpha-LE2, the ERbeta agonist 8beta-VE2, and the nonselective estrogen receptor agonist 17beta-estradiol lowered elevated blood pressure, cardiac mass, and cardiac myocyte cross-sectional areas, as well as increased perivascular collagen accumulation and vascular osteopontin expression in ovariectomized rats receiving chronic aldosterone infusion plus a high-salt diet for 8 weeks. Uterus atrophy was prevented by 16alpha-LE2 and 17beta-estradiol but not by 8beta-VE2. Cardiac proteome analyses by 2D gel electrophoresis, mass spectrometry, and peptide sequencing identified specific subsets of proteins involved in cardiac contractility, energy metabolism, cellular stress response and extracellular matrix formation that were regulated in opposite directions by aldosterone salt treatment and by different estrogen receptor agonists. We conclude that activation of either ERalpha or ERbeta protects the cardiovascular system against the detrimental effects of aldosterone salt treatment and confers redundant, as well as specific, effects on cardiac protein expression. Nonfeminizing ERbeta agonists such as 8beta-VE2 have a therapeutic potential in the treatment of hypertensive heart disease. [less ▲] Detailed reference viewed: 234 (0 UL) Increased mortality and aggravation of heart failure in estrogen receptor-beta knockout mice after myocardial infarction.; ; et al in Circulation (2005), 111(12), 1492-8 BACKGROUND: Lower mortality rates among women with chronic heart failure than among men may depend in part on the action of female sex hormones, especially estrogens. The biological effects of estrogens ... [more ▼] BACKGROUND: Lower mortality rates among women with chronic heart failure than among men may depend in part on the action of female sex hormones, especially estrogens. The biological effects of estrogens are mediated by 2 distinct estrogen receptor (ER) subtypes (ERalpha and ERbeta). The present study was undertaken to determine the role of ERbeta in the development of chronic heart failure after experimental myocardial infarction (MI). METHODS AND RESULTS: Female ERbeta null mice (BERKO(Chapel Hill)) and wild-type littermates (WT) were ovariectomized, given 17beta-estradiol, and subjected to chronic anterior MI (MI; BERKO n=31, WT n=30) or sham operation (sham; BERKO n=14, WT n=14). At 8 weeks after MI, both genotypes revealed left ventricular remodeling and impaired contractile function at similar average infarct size (BERKO-MI 32.9+/-5% versus WT-MI 33.0+/-4%); however, BERKO mice showed increased mortality (BERKO-MI 42% versus WT-MI 23%), increased body weight and fluid retention (P<0.01), higher ventricular pro-ANP expression (BERKO-MI 27.9-fold versus sham, WT-MI 5.2-fold versus sham; BERKO-MI versus WT-MI P<0.001), higher atrial natriuretic peptide serum levels, and increased phospholamban expression (P<0.05) compared with WT mice. CONCLUSIONS: Systemic deletion of ERbeta in female mice increases mortality, aggravates clinical and biochemical markers of heart failure, and contributes to impaired expression of Ca(2+)-handling proteins in chronic heart failure after MI. Further studies are required to delineate the relative importance of cardiac and vascular effects of ERbeta and the role of ERalpha in the development of heart failure. [less ▲] Detailed reference viewed: 155 (0 UL) |
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