Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Estrogen is a key regulatory hormone, which in addition to its role in reproduction, affects a number of physiological systems, including the skeleton and cardiovascular system. The important role of estrogen in various tissues is perhaps most evident in postmenopausal women who, in addition to menopausal symptoms, experience increases in osteoporosis and coronary heart disease as their estrogen levels decline. Estrogen replacement, while effective against osteoporosis and heart disease, produces a number of side effects associated with the breast and uterus which limits compliance. Selective estrogen receptor modulators (SERMs), such as raloxifene and tamoxifen, produce beneficial estrogen-like effects on bone and lipid metabolism, while antagonizing estrogen in reproductive tissue. SERMs can be distinguished from each other in reproductive tissue, particularly the uterus, by their activity profile. For example, while triphenylethylenes like tamoxifen behave as partial agonists, raloxifene (a benzothiophene) behaves as a complete antagonist in the uterus. The SERM profile is distinct from that of full estrogens (ie. 17beta-estradiol or 17alpha-dihydroequilenin) which behave as estrogen agonists in all tissues and pure estrogen antagonists (i.e. ICI-164,384) which exhibit only an estrogen antagonist profile in a battery of tissue types. The precise mechanism by which SERMs produce this tissue-selective pharmacology remains a question. It is clear, however, that for raloxifene, both the estrogen agonist effects on bone and cholesterol metabolism as well as the estrogen antagonist effects in uterine and mammary tissue involve high affinity interaction with the estrogen receptor. The estrogen antagonist activity is mediated via classical pharmacological competition for estrogen receptor binding. The estrogen agonist activity, in bone for example, appears to involve novel post-receptor pathways and non-classical estrogen response element(s) which are activated by SERMs. These novel response elements may represent natural pathways which respond to estrogen metabolites in vivo.
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PMID:Selective estrogen receptor modulators: an alternative to hormone replacement therapy. 942 Dec 6

Estrogen replacement is often advised for postmenopausal women to prevent menopausal symptoms, osteoporosis and heart disease. However, little information is available concerning the half-life of estradiol (E2) in postmenopausal women. This study was designed to determine the half-life and metabolism of transdermal E2. A prospective clinical study of 8 healthy postmenopausal women was performed in the Clinical Research Center of the Brigham and Women's Hospital. A transdermal E2 patch 0.10 mg was placed on the abdominal wall. Thirteen hours later, after an overnight fast, the E2 patch was removed and frequent blood sampling was performed over 6 h. Serum samples were assayed for E2, estrone (E1) and estrone sulfate (E1S). Serum samples were taken before E2 patch placement, for 30 min before patch removal, and for 6 h after patch removal. The basal E2 level of women prior to use of transdermal E2 was 19 +/- 2 pg/ml (mean +/- SE). Thirteen hours after transdermal E2 placement, steady state levels had been reached, with a mean E2 of 112 +/- 6 pg/ml. The mean half-life of E2 after removal of transdermal E2 was 161 min (range 107-221 min). There was a direct relationship between the subjects' weight and the half-life of E2 (r = 0.79, p = 0.02). Mean basal E1 levels were 23 +/- 5 pg/ml and mean E1 steady-state levels after E2 patch placement were 39 +/- 0.6 pg/ml. E1S levels rose from mean basal levels of 1.5 +/- 0.3 ng/ml to mean steady-state levels of 3.1 +/- 0.1 ng/ml after placement of the E2 patch. The apparent half-life of E2 after discontinuing a transdermal E2 patch is 2.7 h or 161 min.
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PMID:Half-life of estradiol in postmenopausal women. 947 64

Cardiovascular disease is the leading cause of death among older American women. Estrogen replacement therapy (ERT) appears to reduce the risk of heart disease. For nearly five decades, the Type A behavior pattern (TABP) has been implicated in the cardiac morbidity and mortality of both men and women, but no studies have examined the use of replacement estrogen or whether its association with heart disease risk factors is different in Type A versus Type B women. We examined the effects of ERT and TABP on heart disease risk factors in a large population-based sample. Subjects were 1070 postmenopausal women, aged 50-89 years, who had been participants in the Rancho Bernardo Study. At a clinic visit made during 1984-1987, TABP was assessed with the Bortner Rating Scale, and heart disease risk factors (total cholesterol, high-density and low-density lipoprotein (HDL and LDL), triglycerides, fasting and postchallenge insulin and glucose, and blood pressure) were measured. Based on a median split (median = 154.0) of scores on the Bortner Rating Scale, 52% of these women were classified as Type A. Type A women were significantly younger than Rating women (mean = 68.4 versus 71.0 years, respectively). After adjustment for age, significantly more Type A than Type B women were on ERT (35% versus 24.7%, p = 0.001). Analyses stratified by TABP indicated that within the Type A group, current users of ERT had higher levels of HDL cholesterol (p) = 0.001) and lower levels of LDL cholesterol (p < 0.01), fasting plasma glucose (p < 0.001), and fasting insulin (p < 0.01). Among Type B women, current users of ERT had higher levels of HDL cholesterol (p = 0.07) and triglycerides (p < 0.01), lower levels of LDL cholesterol (p < 0.01), and lower systolic blood pressure (p < 0.05) but no significant differences in either fasting or postchallenge levels of either plasma glucose or serum insulin (each p < 0.01). Results of this study suggest that ERT may be associated with significant differences in the heart disease risk factor profile in Type A versus Type B women, and these differences may favor Type A women.
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PMID:Type A behavior pattern, heart disease risk factors, and estrogen replacement therapy in postmenopausal women: the Rancho Bernardo Study. 951 Nov 32

The Heart and Estrogen/progestin Replacement Study (HERS) is a randomized, double-blind, placebo-controlled trial designed to test the efficacy and safety of estrogen plus progestin therapy for prevention of recurrent coronary heart disease (CHD) events in women. The participants are postmenopausal women with a uterus and with CHD as evidenced by prior myocardial infarction, coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, or other mechanical revascularization or at least 50% occlusion of a major coronary artery. Between February 1993 and September 1994, 20 HERS centers recruited and randomized 2763 women. Participants ranged in age from 44 to 79 years, with a mean age of 66.7 (SD 6.7) years. Most participants were white (89%), married (57%), and had completed high school or some college (80%). As expected, the prevalence of coronary risk factors was high: 62% were past or current smokers, 59% had hypertension, 90% had serum LDL-cholesterol of 100 mg/dL or higher, and 23% had diabetes. Each woman was randomly assigned to receive one tablet containing 0.625 mg conjugated estrogens plus 2.5 mg medroxyprogesterone acetate daily or an identical placebo. Participants will be evaluated every 4 months for an average of 4.2 years for the occurrence of CHD events (CHD death and nonfatal myocardial infarction). We will also assess other major CHD endpoints, including revascularization and hospitalization for unstable angina. The primary analysis will compare the rate of CHD events in women assigned to active treatment with the rate in those assigned to placebo. The trial was designed to have power greater than 90% to detect a 35% reduction in the incidence of CHD events, assuming a 50% lag in effect for 2 years and a 5% annual event rate in the placebo group. The design, analysis, and conduct of the study are controlled by the Steering Committee of Principal Investigators and coordinated at the University of California, San Francisco. HERS is the largest trial of any intervention to reduce the risk of recurrent CHD events in women with heart disease and is the first controlled trial to seek evidence of the efficacy and safety of postmenopausal hormone therapy to prevent recurrent CHD events.
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PMID:Heart and Estrogen/progestin Replacement Study (HERS): design, methods, and baseline characteristics. 968 9

Cardiovascular disease related to hyperlipidemia is a significant cause of morbidity and mortality in the United States. The benefit of lowering lipid levels in patients with and without cardiovascular disease has been demonstrated in numerous clinical trials. The results of these trials prompted the National Heart, Blood, and Lung Institute to form the Nation Cholesterol Education Panel (NCEP). This panel developed guidelines for identifying and treating lipid disorders. Before starting antilipemic therapy, patients should be evaluated for secondary causes of hyperlipidemia, including disease states and medications. Risk factors for cardiovascular disease should be identified and used to determine the patient's goal low-density lipoprotein level. Regardless of the drug therapy used, the cornerstone treatment for hyperlipidemia is dietary changes. The NCEP recommendation for dietary modification follows a two-step plan to reduce intake of cholesterol and dietary fats. Other nonpharmacologic treatments for hyperlipidemia include exercise, weight reduction for obese patients, reduction of excessive alcohol use, and smoking cessation . Drug therapy should be considered in patients who do not respond to an adequate trial of dietary modifications and lifestyle changes. The principal lipid-lowering agents currently used are the bile acid sequestrants, nicotinic acid, 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors, and fibric acid derivatives. Estrogen, fish oil, and alcohol also can decrease the risk of developing heart disease. In pharmacoeconomic studies, lipid-lowering drug therapy has been shown to decrease the number of procedures, hospitalizations, and other medical interventions required by patients with cardiovascular disease.
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PMID:Identifying and managing patients with hyperlipidemia. 1017 Mar 3

Estrogen deficiency in the postmenopausal woman results in numerous symptomatic and asymptomatic manifestations, including vasomotor symptoms, osteoporosis, heart disease, bladder and vaginal symptoms, and cardiovascular disease. Estrogen replacement therapy is associated with amelioration of these problems but has attendant risks. A newer class of drugs, the selective estrogen receptor modulators, provides both estrogen agonist and antagonist properties, depending on the target tissue. This article discusses the mechanism by which selective estrogen receptor modulators may vary in their end-organ effects and reviews the clinical studies associated with these compounds. Phytoestrogens are widely used in the United States, but little information is available regarding their potential long-term effects.
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PMID:Selective estrogen receptor modulators and phytoestrogens: new therapies for the postmenopausal women. 1037 37

Several studies have reported an association between hormone replacement therapy (HRT) in postmenopausal women and increased risk of idiopathic venous thromboembolic events (VTEs). Given the widespread use of HRT, it is important to identify factors that may predispose women on HRT to VTEs. To address this concern, we examined potential risk factors for VTEs in women assigned to HRT in the Postmenopausal Estrogen/Progestin Interventions (PEPI) study, a three-year, double-blinded, placebo-controlled trial of 875 postmenopausal women designed to assess the effects of HRT on heart disease risk factors (HDL cholesterol, fibrinogen, blood pressure, and insulin). Women with a history of estrogen-associated VTEs were excluded from the trial. Ten women, all assigned to HRT, had a VTE during PEPI. Only baseline fibrinogen varied significantly between those who did (mean = 249.0 mg/dl) and did not (mean = 280.8 mg/dl) have a VTE while assigned to HRT (P < 0.03). Adjusting for covariates including age, smoking, body mass index, lipid levels, blood pressure, alcohol, exercise, and prior HRT or oral contraceptive use did not affect this finding. The significantly lower fibrinogen levels seen among women subsequently reporting VTEs may be a marker for a specific, but as yet undefined, coagulopathy that is magnified in the presence of exogenous hormones. However, larger studies are needed to confirm this finding.
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PMID:Low fibrinogen level: A predisposing factor for venous thromboembolic events with hormone replacement therapy. 1044 Sep 16

The isoprenoid metabolic pathway is mainly regulated at the level of conversion of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) to mevalonate, catalyzed by HMG CoA reductase. As estrogens are known to influence cholesterol metabolism, we have explored the potential regulation of the HMG CoA reductase gene promoter by estrogens. The promoter contains an estrogen-responsive element-like sequence at position -93 (termed Red-ERE), which differs from the ERE consensus by one mismatch in each half of the palindrome. A Red-ERE oligonucleotide specifically bound estrogen receptor in vitro and conferred receptor-dependent estrogen responsiveness to a heterologous promoter in all cell lines tested. However, expression of a reporter driven by the rat HMG CoA reductase promoter was induced by estrogen treatment after transient transfection into the breast cancer cell line MCF-7 cells but not in hepatic cell lines expressing estrogen receptor. Estrogen induction in MCF-7 cells was dependent on the Red-ERE and was strongly inhibited by the antiestrogen ICI 164,384. A functional cAMP-responsive element is located immediately upstream of the Red-ERE, but cAMP and estrogens inhibit each other in terms of transactivation of the promoter. Similarly, induction by estrogens was inhibited by micromolar concentrations of cholesterol, likely acting via changes in occupancy of the sterol-responsive element located 70 bp upstream of the Red-ERE. Thus, within its natural context, Red-ERE is able to mediate hormonal regulation of the HMG CoA reductase gene in tissues that respond to estrogens with enhanced cell proliferation, while it is not operative in liver cells. We postulate that this tissue-specific regulation of HMG CoA reductase by estrogens could partially explain the protective effect of estrogens against heart disease.
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PMID:The promoter of the rat 3-hydroxy-3-methylglutaryl coenzyme A reductase gene contains a tissue-specific estrogen-responsive region. 1044 99

The Heart and Estrogen/progestin Replacement Study (HERS) found no overall effect of 4.1 years of therapy with estrogen plus progestin for secondary prevention of coronary heart disease in postmenopausal women. However, within the overall null effect, a 50% increase in cardiovascular events was seen in the first year, followed by fewer events after 2 years of treatment in the hormone therapy group than in the placebo group. Understanding the cause of this pattern of early increase and late reduction in risk is key to interpreting the HERS results and reconciling them with the large number of observational and other studies of the cardiovascular effects of estrogen. There are two possibilities. One is that the HERS regimen of estrogen plus progestin has no effect on risk for heart disease, and the pattern of changing risk over time is simply the result of chance or confounding. The other is that the pattern of early increase and late reduction in risk is due to real but opposing effects of this regimen. Several lines of evidence support each possibility. Attrition of a susceptible cohort of women uniquely at risk for a cardiovascular complication from hormone therapy coupled with a gradually progressive beneficial effect due to lipid lowering and other factors is a promising potential explanation. The HERS results remind us of the need for clinical trials to evaluate both the benefits and risks of new therapies. They also illustrate how much more we need to know about the cardiovascular effects of hormone replacement therapy.
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PMID:The HERS trial results: paradigms lost? Heart and Estrogen/progestin Replacement Study. 1049 64

In women, serum lipid levels and the incidence of myocardial ischemia increase after menopause. Deficiency of estrogen is believed to be the cause of these epidemiological phenomena. On the other hand, hormone replacement therapy(HRT), has prevailed in developed countries. Estrogen is replaced to ease climacteric disorders, and retard bone loss. Many clinical studies cleared the effect of HRT on lipids, in which total and LDL-C (cholesterol) decreased, and HDL-C increased. TG increased by conjugated equilin estrogen but not by transdermal estradiol. In our study, hepatic triglyceride lipase(HTGL) was suppressed by HRT, but lipoprotein lipase(LpL) was not suppressed. HRT decreases coronary artery diseases, but it is still controversial whether HRT is efficient in patients who already have heart disease.
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PMID:[Efficacy of hormone replacement therapy on hyperlipidemia]. 1063 24


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