Experimental benefits of sex hormones on vascular function and the outcome of hormone therapy in cardiovascular disease

Unveiling the Pharmacological and Nanotechnological Facets of Daidzein: Present State-of-the-Art and Future Perspectives

Herbal drugs have been attracting much scientific interest in the last few decades and nowadays, phytoconstituents-based research is in progress to disclose their unidentified medicinal potential. Daidzein (DAI) is the natural phytoestrogen isoflavone derived primarily from leguminous plants, such as the soybean and mung bean, and its IUPAC name is 4',7-dihydroxyisoflavone. This compound has received great attention as a fascinating pharmacophore with remarkable potential for the therapeutic management of several diseases. Certain pharmacokinetic properties of DAI such as less aqueous solubility, low permeability, and poor bioavailability are major obstacles restricting the therapeutic applications. In this review, distinctive physicochemical characteristics and pharmacokinetics of DAI has been elucidated. The pharmacological applications in treatment of several disorders like oxidative stress, cancer, obesity, cardiovascular, neuroprotective, diabetes, ovariectomy, anxiety, and inflammation with their mechanism of action are explained. Furthermore, this review article comprehensively focuses to provide up-to-date information about nanotechnology-based formulations which have been investigated for DAI in preceding years which includes polymeric nanoparticles, solid lipid nanoparticles, nanostructured lipid carrier, polymer-lipid nanoparticles, nanocomplexes, polymeric micelles, nanoemulsion, nanosuspension, liposomes, and self-microemulsifying drug delivery systems.

Antiphospholipid Syndrome-Related Pulmonary Embolism: Clinical Characteristics and Early Recognition

Background

Pulmonary thromboembolism is a common disease frequently encountered in the emergency room and has a high mortality rate. Antiphospholipid syndrome (APS) is a high-risk factor for recurrent pulmonary embolism (PE). It is critical to effectively administer anticoagulants to avoid the recurrence of thrombotic events. This study aims to identify the clinical characteristics of APS patients with PE (APS-PE) and to develop a risk score for determining the presence of APS in PE patients in the emergency situations.

Methods

We retrospectively enrolled 76 PE patients in this study, with 46 patients in the APS-PE group and 30 patients in the non-APS-PE group. We compared differences in demographics, laboratory parameters, and early mortality risk between the two groups. Risk factors for APS-PE were screened using logistic regression analysis. We also developed an early risk score using multivariate analysis weighted points proportional to the β- regression coefficient values and calculated the sensitivity and specificity for APS in PE patients.

Results

In the APS-PE group, we observed a higher proportion of males (43.6 vs. 20%), a higher proportion of low-risk patients (58.7 vs. 10%), lower levels of white blood cells and platelets (PLT), longer activated partial thromboplastin time (APTT), and a slight increase in D-dimer levels. Patients who were triple positive for antiphospholipid antibodies (aPLs) were younger. The APTT gradually increased as the number of positive aPLs increased. The risk factors for APS included male (OR = 5.565, 95% CI 1.176–26.341), decreased PLT (OR = 0.029, 95% CI 0.003–0.330), slightly increased D-dimer (OR = 0.089, 95% CI 0.019–0.426), and prolonged APTT (OR = 4.870, 95% CI 1.189–19.951). The risk score was named MPDA and included male, PLT, D-dimer and APTT, which can predict APS in PE patients with the AUC at 0.888 (95% CI 0.811–0.965).

Conclusion

The risk factors for APS in PE patients are male, low PLT, prolonged APTT and slightly increased D-dimer. The MPDA is a quantitative scoring system which is highly suggestive of APS in PE patients.

Uterine Vascular Control Preconception and During Pregnancy

Successful pregnancy and reproduction are dependent on adequate uterine blood flow, placental perfusion, and vascular responsivity to fetal demands. The ability to support pregnancy centers on systemic adaptation and endometrial preparation through decidualization, embryonic implantation, trophoblast invasion, arterial/arteriolar reactivity, and vascular remodeling. These adaptations occur through responsiveness to endocrine signaling and local uteroplacental mediators. The purpose of this article is to highlight the current knowledge associated with vascular remodeling and responsivity during uterine preparation for and during pregnancy. We focus on maternal cardiovascular systemic and uterine modifications, endometrial decidualization, implantation and invasion, uterine and spiral artery remodeling, local uterine regulatory mechanisms, placentation, and pathological consequences of vascular dysfunction during pregnancy. © 2021 American Physiological Society. Compr Physiol 11:1-23, 2021.

In silico health effect prioritization of environmental chemicals through transcriptomics data exploration from a chemo-centric view

With the explosive growth of synthetic compounds, the health effects caused by exogenous chemical exposure have attracted more and more public attention. The prediction of health effect is a never-ending story. Collective resource of transcriptomics data offers an opportunity to understand and identify the multiple health effects of small molecule. Inspired by the fact that environmental chemicals of high health risk frequently share both similar gene expression profile and common structural feature of certain drugs, we here propose a novel computational effect prioritization method for environmental chemicals through transcriptomics data exploration from a chemo-centric view. Specifically, non-negative matrix factorization (NMF) method has been adopted to get the association network linking structural features with transcriptomics characteristics of drugs with specific effects. The model yields 13 pivotal types of effects, so-called components, that represent drug categories with common chemo- and geno- type features. Moreover, the established model effectively prioritizes potential toxic effects for the external chemicals from the endocrine disruptor screening program (EDSP) for their potential estrogenicity and other verified risks. Even if only the highest priority is set for the estrogenic effect, the precision and recall can reach 0.76 and 0.77 respectively for these chemicals. Our effort provides a successful endeavor as to profile potential toxic effects simultaneously for environmental chemicals using both chemical and omics data.

Elevated circulating luteinizing hormone levels are associated with diabetic macroalbuminuria in Chinese men and postmenopausal women: A cross-sectional study

BACKGROUND

Associations between sex hormones and diabetic vascular complications have recently been studied, but the role luteinizing hormone (LH) plays in diabetic kidney disease (DKD) remains uncertain. We aimed to investigate the relationship of LH and DKD in Chinese men and postmenopausal women with type 2 diabetes mellitus (T2DM).

METHODS

Data were collected from 1775 T2DM men and postmenopausal women in hospital. The odds ratios (OR) and corresponding 95% confidence intervals (CI) in relation to LH quartiles were obtained by multiple logistic regression analysis.

RESULTS

LH levels were significantly higher in patients with macroalbuminuria than in those with microalbuminuria, but were not higher in patients with microalbuminuria than in those with normoalbuminuria. Consistently, LH in those with an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73m² were significantly higher than in those with eGFR≥60 mL/min/1.73m² . The prevalence of macroalbuminuria was obviously increased for subjects of the fourth quartile of LH vs the first to third quartile (20.4% vs 6.2%, 8.0%, 12.2% in men; 25.3% vs 5.5%, 3.8%, 9.3% in postmenopausal women). Multivariate logistic regression demonstrated that subjects within the highest quartile of LH had higher odds of macroalbuminuria than those within the lowest quartile (OR 4.00, 95% CI, 1.87-8.55 for men; OR 9.62, 95% CI, 3.42-27.08 for postmenopausal women), independent of age, diabetes duration, or other metabolic factors. The area under the curve for detecting macroalbuminuria based on LH was 0.662 for men, and 0.767 for postmenopausal women.

CONCLUSION

High LH levels are positively associated with established DKD among Chinese men and postmenopausal women. Elevated LH may be a promising clinical factor for identifying established DKD.

Sex differences in the coagulation process and microvascular perfusion induced by brain death in rats

Brain death (BD) leads to a systemic inflammation associated with the activation of coagulation, which could be related to decreased microcirculatory perfusion. Evidence shows that females exhibit higher platelet aggregability than males. Thus, we investigated sex differences in platelets, coagulation and microcirculatory compromise after BD. BD was induced in male and female (proestrus) Wistar rats. After 3 h, we evaluated: (i) intravital microscopy to evaluate mesenteric perfusion and leucocyte infiltration; (ii) platelet aggregation assay; (iii) rotational thromboelastometry; and (iv) Serum NO x - . Female rats maintained the mesenteric perfusion, whereas male reduced percentage of perfused vessels. Male BD presented higher platelet aggregation than the controls. In contrast, female BD had lower platelet aggregation than the control. Thromboelastometry indicated a reduction in clot firmness with increased clotting time in the female group compared with the male group. Serum NO x - level in female BD was higher than that in the male BD and female control. There is sex dimorphism in platelet function and clotting process, which are altered in different ways by BD. Thus, it is possible to connect the reduction in microcirculatory perfusion in males to intravascular microthrombi formation and the maintenance of perfusion in females to a higher inflammatory response and NO synthesis.

Systemic NOS inhibition reduces contracting muscle oxygenation more in intact female than male rats

Females respond to baroreceptor stimulation with enhanced modulation of heart rate (HR) to regulate blood pressure and also express greater reliance on nitric oxide (NO) for vascular control compared to males. Sex differences in muscle oxygenation consequent to central hemodynamic challenge induced by systemic NO synthase (NOS) inhibition are unknown. We tested the hypotheses that systemic NOS inhibition would induce lower contracting skeletal muscle oxygenation in females compared to males. The spinotrapezius of Sprague-Dawley rats (females (♀) = 9, males (♂) = 9) was surgically exposed and contracted by electrical stimulation (180s, 1 Hz, ~6 V) under pentobarbital sodium anesthesia. Oxyphor G4 was injected into the muscle and phosphorescence quenching was used to measure the interstitial PO₂ (PO₂is, determined by O₂ delivery-to-utilization matching) under control (Krebs-Henseleit solution) and after intra-arterial infusion of nitro-l-arginine methyl ester (l-NAME; NOS blockade; 10 mg kg^-1). At rest, females showed a greater PO₂is increase (ΔPO₂is/ΔMAP) and HR (ΔHR/ΔMAP) reduction than males in response to the elevated MAP induced by systemic NOS inhibition (both p < 0.05). Following l-NAME, during the contracting steady-state, females exhibited lower PO₂is than males (♂: 17.1 ± 1.4 vs ♀: 10.8 ± 1.4 mmHg, p < 0.05). The rate pressure product was lower in females than males (♂: 482 ± 14 vs ♀: 392 ± 29, p < 0.05) and correlated with the steady-state PO₂is (r = 0.66, p < 0.05). These results support that females express greater reductions in HR than males in response to l-NAME-induced elevation of MAP via the baroreceptor reflex and provide new insights on how central hemodynamics affect skeletal muscle oxygenation in a sex-specific manner.

Oral Contraceptive Use and Increased Risk of Stroke: A Dose-Response Meta-Analysis of Observational Studies

Background: Oral contraceptive (OCP) use might increase the risk of stroke in women. We examined a possible dose–response relation between OCP use and the risk of stroke in young and middle-aged women.

Methods: A retrieval of PubMed and EMBASE databases was performed. We selected observational studies that reported odds ratios (ORs) with 95% confidence intervals (CIs) for the risk of stroke in OCP users. A two-stage dose–response analysis was conducted using the random-effects model and the restricted spline model.

Results: A total of 6 cohort studies and 12 case–control studies were included, which involved 2,143,174 participants and 11,661 cases of stroke including ischemic stroke (IS), hemorrhagic stroke (HS), and stroke of unknown origin. The pooled ORs of total stroke were 1.19 (95% CI, 1.16–1.23) for every 10-μg increment in estrogen dosage, 1.20 (95% CI, 1.05–1.37) for every 5-years increment in duration of OCP use, and 0.82 (95% CI, 0.68–0.98) for every 5-years increment in duration of OCP cessation. The ORs of IS were 1.20 (95% CI, 1.17–1.22) in estrogen dosage, 1.24 (95% CI, 1.04–1.49) in duration of OCP use, and 0.78 (95% CI, 0.67–0.92) in duration of OCP cessation. The ORs of HS were 1.10 (95% CI, 1.04–1.16) in estrogen dosage, 1.13 (95% CI, 0.93–1.36) in duration of OCPs, and 0.71 (95% CI, 0.55–0.92) in duration of OCP cessation. The pooled ORs of total stroke from prospective studies (1.12; 95% CI, 1.01–1.24) were lower than those from retrospective studies (1.30; 95% CI, 1.01–1.67).

Conclusions: The higher estrogen dosage significantly increased the risks of total stroke, IS, and HS, respectively. The longer duration of OCP use significantly increased the risks of total stroke and IS, but its effects on HS risk were marginal. The longer duration of OCP cessation significantly decreased the risks of total stroke, IS, and HS, respectively. These findings affirm the contribution of estrogen dose and duration of OCP use to the increased risk of stroke, which may be critical for the instruction of OCP use and the prevention and management of cerebrovascular diseases.

Characteristics and Prognosis in Women and Men With Type 1 Diabetes Undergoing Coronary Angiography: A Nationwide Registry Report

OBJECTIVE

To describe sex aspects on extent of coronary artery disease (CAD) and prognosis in a contemporary population with type 1 diabetes.

RESEARCH DESIGN AND METHODS

All patients undergoing coronary angiography, 2001-2013, included in the Swedish Coronary Angiography and Angioplasty Registry and the Swedish National Diabetes Register as type 1 diabetes were followed for mortality until 31 December 2013. The coronary angiogram was classified into normal, one-vessel disease, two-vessel disease, three-vessel disease, and left main stem disease.

RESULTS

In all, 2,776 patients (42% women) with mean age 58 years (SD 11) were followed for 7.2 years (SD 2.2). Diabetes duration was longer in women (37 ± 14 vs. 34 ± 14 years in men; P < 0.001), who also had more retinopathy (68% vs. 65%; P = 0.050), whereas microalbuminuria was less common (41% vs. 51%; P < 0.001). Indications for coronary angiography did not substantially differ in women and men. The extent of CAD was somewhat less severe in women (normal angiogram 23.5% vs. 19.1%, three-vessel and left main stem disease 34.5% vs. 40.4%; P = 0.002), whereas mortality did not differ (adjusted hazard ratio 1.03 [95% CI 0.88-1.20]; P = 0.754). The standard mortality ratio for women the first year was 7.49 (5.73-9.62) and for men was 4.58 (3.60-5.74).

CONCLUSIONS

In patients with type 1 diabetes admitted for coronary angiography, the extent of CAD was almost similar in women and men, and total long-term mortality did not differ. Type 1 diabetes was associated with higher mortality risk in women than in men when compared with the general population. These data support that type 1 diabetes attenuates the cardiovascular risk difference seen in men and women in the general population.

Different Effects of Oral Contraceptive and Dydrogesterone Treatment on Oxidative Stress Levels in Premenopausal Women

Background

The aim of the study was to observe the changes in blood oxidative stress levels by oral contraceptive (OC) and/or dydrogesterone (DG) treatment.

Methods

A retrospective cohort of 27 premenopausal women with primary dysmenorrhea consisted of the OC treatment group (N = 17) and the DG treatment group (N = 10) by choice of the initial treatment. The OC group included two subgroups: patients with continuous OC treatment (treated for at least 15 months, N = 10) and patients with discontinuous OC treatment (switched to DG treatment after approximately 6 months of initial OC treatment: N = 7). The DG group had 15 months of continuous DG treatment. Blood parameters, including diacron-reactive oxygen metabolites (d-ROMs: an oxidative stress marker), were measured.

Results

The d-ROMs level was elevated in the OC group 3 months after initial treatment (mean: from 321 (at baseline) to 512 Carratelli Units (Carr U); P < 0.01), while such changes were not observed in the DG group. The d-ROMs level was reduced in the discontinuous OC subgroup 15 months after initial treatment (from 508 (3 months after initial treatment) to 372 Carr U; P < 0.01), while such changes were not observed in the continuous OC subgroup. The DG group displayed unchanged the d-ROMs level.

Conclusion

Replacing OC with DG can attenuate oxidative stress as elevated by OC, thereby alleviating the possible vascular risks with OC treatment.

BH4 improves postprandial endothelial function after a high-fat meal in men and postmenopausal women

OBJECTIVE

The timing and duration of menopause is important when evaluating the risk for cardiovascular disease in postmenopausal women, likely related in part to nitric oxide (NO) bioavailability. The flow-mediated dilation (FMD) test is a noninvasive assessment of NO bioavailability in humans, and tetrahydrobiopterin (BH4) is essential for NO synthesis. A high-fat meal (HFM) has been used to increase lipemia and reduce NO bioavailability. Thus, this study sought to determine if menopausal transition has any impact on the postprandial endothelial function response to a HFM, and evaluate the effect of BH4 on postprandial endothelial function in postmenopausal women and men.

METHODS

Utilizing a randomized, double-blind, placebo-controlled design, sex-steroid hormones and FMD were determined in 30 older adults (10 postmenopausal women aged below 3 y [W < 3], 10 postmenopausal women aged above 10 y [W > 10], and 10 men) at baseline and 4 hours after the ingestion of a HFM alone or a HFM with BH4 (HFM + BH4; 5 mg/kg).

RESULTS

Data are presented as mean ± SEM. Independent of treatment, postprandial testosterone was significantly (P < 0.05) decreased in men (-64 ± 11 ng/dL), whereas no changes were observed in W < 3 or W > 10 group. In addition, concentrations of progesterone were higher (P = 0.019) and the testosterone/estradiol ratio was lower (P = 0.026) in all groups after the ingestion of HFM + BH4 compared with the ingestion of HFM alone. Overall, an increase in FMD was observed after the ingestion of HFM + BH4 (Δ1.9% ± 0.6%), whereas no change in FMD was observed after the ingestion of HFM alone (Δ-0.7% ± 0.6%).

CONCLUSIONS

Co-ingestion of BH4 with a HFM not only alters the sex-steroid hormone ratio, it improves postprandial FMD after a HFM regardless of postmenopause status or sex.

Eating and arterial endothelial function: a meta-analysis of the acute effects of meal consumption on flow-mediated dilation

Given that endothelial dysfunction precedes atherosclerotic cardiovascular disease, exploring the parameters that modify postprandial flow-mediated dilation (FMD) is important for public health. The objectives of the study are to estimate the population effect of meal ingestion on FMD and to determine how the effect varied based on patient characteristics and modifiable methodological features. Articles published before June 2015 were located using MEDLINE, PubMed and Web of Science. One hundred fifty-four effects were derived from 78 articles involving 2,548 subjects were selected. Included articles required measurement of FMD in adults before and after meal ingestion. Effects were analysed using an unstandardized mean gain random effects model, and significant moderators were analysed using meta-regression. Meal consumption significantly reduced FMD by a heterogeneous mean effect size delta (Δ) of -2.03 (95% CI: [-2.28, -1.77]), an ~2% reduction in FMD. FMD reductions were larger among normal weight individuals, males, those with a cardio-metabolic disorder, those with elevated baseline FMD, and individuals with impaired glucose tolerance at baseline. Macronutrient meal ingestion significantly reduced FMD, an effect that was moderated by body mass index, sex and two-way interactions between disease status and both baseline FMD and baseline blood glucose levels.

Synergistic Effect of a Physiological Ratio of Estradiol and Testosterone in the Treatment of Early-stage Atherosclerosis

BACKGROUND AND AIMS

Clinical trials and epidemiological data suggest that estrogen replacement therapy (ERT) fails to reduce cardiovascular events in postmenopausal women with coronary heart disease (CHD). The high concentration of estrogen supplementation may increase the risk of thrombosis and result in testosterone deficiency, which is considered the main reason for failure. Thus, we hypothesized that a physiologic dosage of estradiol combined with testosterone may become a new therapeutic strategy in postmenopausal women with CHD.

METHODS AND RESULTS

We used human umbilical vein endothelial cells (HUVECs) and female C57BL/6 mice as the experimental subjects. With the HUVECs, we found an appropriate E2/T ratio of 5:1 (5×10(-8) mol/L estradiol and 10(-8) mol/L testosterone), which has a significant anti-apoptotic effect on HUVECs by inducing a C-reactive protein. In the in vivo study, we verified the beneficial effects of the defined appropriate E2/T ratio in mice with early stage atherosclerosis. We found that replacement therapy with the defined appropriate E2/T ratio had beneficial effects of reducing the lipid lesions, reducing the formation of foam cells, reducing endothelial injury, modulating the coagulation system function and inhibiting inflammation and was significantly more effective than either estradiol or testosterone supplementation alone.

CONCLUSION

The present study demonstrated that estradiol and testosterone have a synergistic effect on early stage atherosclerosis, and replacement therapy with the defined appropriate E2/T ratio can significantly suppress the development of atherosclerosis through reducing the lipid lesions, reducing the formation of foam cells, reducing endothelial injury, modulating the coagulation system function and inhibiting inflammation.

Applying the Gender Lens to Risk Factors and Outcome after Adult Cardiac Surgery

Background

Applying the gender lens to risk factors and outcome after adult cardiac surgery is of major clinical interest, as the inclusion of sex and gender in research design and analysis may guarantee more comprehensive cardiovascular science and may consecutively result in a more effective surgical treatment as well as cost savings in cardiac surgery.

Methods

We have reviewed classical cardiovascular risk factors (diabetes, arterial hypertension, hyperlipidemia, smoking) according to a gender-based approach. Furthermore, we have examined comorbidities such as depression, renal insufficiency, and hormonal influences in regard to gender. Gender-sensitive economic aspects have been evaluated, surgical outcome has been analyzed, and cardiovascular research has been considered from a gender perspective.

Results

The influence of typical risk factors and outcome after cardiac surgery has been evaluated from a gender perspective, and the gender-specific distribution of these risk factors is reported on. The named comorbidities are listed. Economic aspects demonstrated a gender gap. Outcome after coronary and valvular surgeries as well as after heart transplantation are displayed in this regard. Results after postoperative use of intra-aortic balloon pump are shown. Gender-related aspects of clinical and biomedical cardiosurgical research are reported.

Conclusions

Female gender has become an independent risk factor of survival after the majority of cardiosurgical procedures. Severely impaired left ventricular ejection fraction independently predicts survival in men, whereas age does in females.

Progesterone supplementation attenuates hypertension and the autoantibody to the angiotensin II type I receptor in response to elevated interleukin-6 during pregnancy

OBJECTIVE

Preeclampsia is a multisystem disorder recognized as hypertension with proteinuria developing >20 weeks' gestation. Preeclampsia is associated with chronic immune activation characterized by increased T and B lymphocytes, cytokines, and antibodies activating the angiotensin II type I receptor (AT1-AA). Hypertension in response to elevated interleukin (IL)-6 during pregnancy occurs with increased renin activity and AT1-AA, and reduced kidney function.

STUDY DESIGN

We aim to determine whether 17-alpha-hydroxyprogesterone caproate (17-OHPC), progesterone, improved inflammatory pathways during elevated IL-6 in pregnant rats. IL-6 (5 ng/d) was infused via miniosmotic pumps into normal pregnant (NP) rats beginning on day 14 of gestation and 17-OHPC (3.32 mg/kg) was diluted in normal saline and injected on day 18. Blood pressure (mean arterial pressure [MAP]) determination and serum collection were performed on day 19 of gestation.

RESULTS

MAP in NP was 100 ± 3 mm Hg, which increased with IL-6 to 112 ± 4 mm Hg (P < .05). Pregnant rats given 17-OHPC alone had a MAP of 99 ± 3 mm Hg and MAP increased to 103 ± 2 mm Hg in IL-6+17-OHPC. AT1-AA was 1.2 ± 0.5 bpm in NP rats, increased to 17 ± 9 bpm with IL-6 infusion but administration of 17-OHPC significantly blunted AT1-AA to 4 ± 0.8 bpm in NP+IL-6+17-OHPC. Total circulating nitrate/nitrite was significantly decreased and placental Ser(1177)-phosporylated-eNOS/eNOS was lowered with IL-6 infusion. Supplementation of 17-OHPC significantly improved placental Ser(1177)-phosporylated-eNOS/eNOS however, circulating nitrate/nitrite was unchanged with 17-OHPC supplementation.

CONCLUSION

This study illustrates that 17-OHPC attenuated hypertension, decreased AT1-AA activity, and improved placental nitric oxide in response to elevated IL-6 during pregnancy and could lend hope to a new potential therapeutic for preeclampsia.

Regulation of endothelial nitric oxide synthase and high-density lipoprotein quality by estradiol in cardiovascular pathology

Estrogens have been recognized, in the last 3 decades, as important hormones in direct and indirect modulation of vascular health. In addition to their direct benefit on cardiovascular health, the presence of esterified estrogen in the lipid core of high-density lipoprotein (HDL) particles indirectly contributes to atheroprotection by significantly improving HDL quality and functionality. Estrogens modulate their physiological activity via genomic and nongenomic mechanisms. Genomic mechanisms are thought to be mediated directly by interaction of the hormone receptor complex with the hormone response elements that regulate gene expression. Nongenomic mechanisms are thought to occur via interaction of the estrogen with membrane-bound receptors, which rapidly activate intracellular signaling without binding of the hormone receptor complex to its hormone response elements. Estradiol in particular mediates early and late endothelial nitric oxide synthase (eNOS) activation via interaction with estrogen receptors through both nongenomic and genomic mechanisms. In the vascular system, the primary endogenous source of nitric oxide (NO) generation is eNOS. Nitric oxide primarily influences blood vessel relaxation, the heart rate, and myocyte contractility. The abnormalities in expression and/or functions of eNOS lead to the development of cardiovascular diseases, both in animals and in humans. Although considerable research efforts have been dedicated to understanding the mechanisms of action of estradiol in regulating cardiac eNOS, more research is needed to fully understand the details of such mechanisms. This review focuses on recent findings from animal and human studies on the regulation of eNOS and HDL quality by estradiol in cardiovascular pathology.

Protective actions of progesterone in the cardiovascular system: potential role of membrane progesterone receptors (mPRs) in mediating rapid effects

The protective functions of progesterone in the cardiovascular system have received little attention even though evidence has accumulated that progesterone lowers blood pressure, inhibits coronary hyperactivity and has powerful vasodilatory and natriuretic effects. One possible reason why potential beneficial actions of progesterone on cardiovascular functions have not been extensively studied is that divergent effects to those of progesterone have been observed in many clinical trials with synthetic progestins such as medroxyprogesterone acetate which are associated with increased risk of coronary disease. Evidence that progesterone exerts protective effects on cardiovascular functions is briefly reviewed. The finding that progesterone administration decreases blood vessel vasoconstriction in several animal models within a few minutes suggests that rapid, nongenomic progesterone mechanisms are of physiological importance in regulating vascular tone. Rapid activation of second messenger pathways by progesterone has been observed in vascular endothelial and smooth muscle cells, resulting in alterations in endothelial nitric oxide synthase (eNOS) activity and calcium influx, respectively. Both nuclear progesterone receptors (PRs) and novel membrane progesterone receptors (mPRs) are candidates for the intermediaries in these rapid, cell-surface initiated progesterone actions in endothelial and smooth muscle vascular cells. PRs have been detected in both cell types. New data are presented showing mPRα, mPRβ and mPRγ are also present in human endothelial and smooth muscle vascular cells. Preliminary evidence suggests mPRs mediate rapid progestin signaling in these endothelial cells, resulting in down-regulation of cAMP production and increased nitric oxide synthesis. The role of mPRs in progesterone regulation of cardiovascular functions warrants further investigation.

Type 2 diabetes and cardiovascular disease in women

Cardiovascular disease is the leading cause of death in both men and women. This is also true for patients with diabetes. In general, differences between the sexes are present in several areas, such as epidemiology, pathophysiology, diagnostics, treatment response and prognosis, as well as the way in which disease is experienced and expressed. Cardiovascular disease presents later in life in women, who are therefore more likely to suffer from comorbidities. However, this age-related difference is attenuated in women with diabetes, who suffer their first myocardial infarction at about the same age as men with diabetes. Diabetes mellitus increases the risk of cardiovascular disease by three to four times in women and two to three times in men, after adjusting for other risk factors. This paper describes the differences in cardiovascular disease in men and women and the special situation of women with type 2 diabetes when it comes to risk factors, symptoms and the setting of acute coronary syndromes. Furthermore, it highlights the importance of sex-specific analyses in clinical research to improve our knowledge of cardiovascular disease in women in general and in women with diabetes in particular. The importance of taking sex into account when treating women and men at risk of cardiovascular disease is discussed.

Oral contraceptive therapy increases oxidative stress in pre-menopausal women

Background:

Oral contraceptive therapy (OCT) is associated with an increased risk of deep vein thrombosis, venous thromboembolism and stroke. However, the underlying mechanisms have not yet been elucidated. The objective of this study was to investigate the influence of OCT on blood levels of an oxidative stress maker in pre-menopausal women.

Methods:

Oxidative stress was determined in 87 pre-menopausal healthy women (24 with and 63 without OCT) using a blood assay for reactive oxygen metabolites (by the d-ROMs test). The subjects with OCT received a triphasic preparation consisting of ethinyl estradiol and norethisterone.

Results:

Subjects with OCT showed significantly higher d-ROMs levels (median: 380; interquartile range: 328-502 Carr U) than those without OCT (325 [271-369]; P < 0.05). The results remained the same after adjusting for potential confounders.

Conclusions:

The use of OCT may increase oxidative stress levels, independent of traditional cardiovascular risk factors, in pre-menopausal women, providing new insights to the primary prevention of vascular complications in these subjects.

Vascular effects of phytoestrogens and alternative menopausal hormone therapy in cardiovascular disease

Phytoestrogens are estrogenic compounds of plant origin classified into different groups including isoflavones, lignans, coumestans and stilbenes. Isoflavones such as genistein and daidzein are the most studied and most potent phytoestrogens, and are found mainly in soy based foods. The effects of phytoestrogens are partly mediated via estrogen receptors (ERs): ERα, ERβ and possibly GPER. The interaction of phytoestrogens with ERs is thought to induce both genomic and non-genomic effects in many tissues including the vasculature. Some phytoestrogens such as genistein have additional non-ER-mediated effects involving signaling pathways such as tyrosine kinase. Experimental studies have shown beneficial effects of phytoestrogens on endothelial cells, vascular smooth muscle, and extracellular matrix. Phytoestrogens may also affect other pathophysiologic vascular processes such as lipid profile, angiogenesis, inflammation, tissue damage by reactive oxygen species, and these effects could delay the progression of atherosclerosis. As recent clinical trials showed no vascular benefits or even increased risk of cardiovascular disease (CVD) and CV events with conventional menopausal hormone therapy (MHT), phytoestrogens are being considered as alternatives to pharmacologic MHT. Epidemiological studies in the Far East population suggest that dietary intake of phytoestrogens may contribute to the decreased incidence of postmenopausal CVD and thromboembolic events. Also, the WHO-CARDIAC study supported that consumption of high soybean diet is associated with lower mortalities from coronary artery disease. However, as with estrogen, there has been some discrepancy between the experimental studies demonstrating the vascular benefits of phytoestrogens and the data from clinical trials. This is likely because the phytoestrogens clinical trials have been limited in many aspects including the number of participants enrolled, the clinical end points investigated, and the lack of long-term follow-up. Further investigation of the cellular mechanisms underlying the vascular effects of phytoestrogens and careful evaluation of the epidemiological evidence and clinical trials of their potential vascular benefits would put forward the use of phytoestrogens as an alternative MHT for the relief of menopausal symptoms and amelioration of postmenopausal CVD.

Increased risk of stroke in oral contraceptive users carried replicated genetic variants: a population-based case-control study in China

Combined oral contraceptives (COC) use is a unique risk factor for stroke in women, and may modify the associations between genetic polymorphisms and stroke. To investigate whether the genetic variants identified in a recent genome-wide association study (GWAS) could be replicated in Chinese women, as well as, whether related risk was different in COC users, 451 stroke cases and 831 age- and region-matched controls were recruited from our cohort. Genotyping of 3 SNPs (rs700651, rs10958409, and rs1333040) was performed by the polymerase chain reaction assay with TaqMan probes. The history of contraceptive use and relevant information were obtained from a face-to-face interview. Odds ratios (OR) with 95 % confidence interval (CI) were estimated under conditional logistic regression model after adjustment for cardiovascular covariates. Our study replicated the associations of rs10958409 and rs1333040, with the risk of stroke, especially hemorrhagic subtype, but failed to confirm association of rs700651. COC use was associated with a 1.56-fold (OR 1.56, 95 % CI 1.21-2.01) increased risk of stroke. COC users with rs10958409 GA/AA or rs1333040 CT/TT genotypes had an increased risk of overall stroke by 1.59-fold (OR 2.59, 95 % CI 1.59-4.19) and 3.24-fold (OR 4.24, 95 % CI 1.71-10.49), respectively, compared with the non-users with wild-type genotypes. Moreover, the risk of hemorrhagic stroke increased by 4.81- and 15.06-fold when risk allele carriers of rs10958409 or rs1333040 who took COC. Our results confirmed the associations of two GWAS SNPs, also suggested combination effects of these genetic variants and COC use on stroke risk.

Elderly women with heart failure: unseen, unheard or simply forgotten?

In developed countries, cardiovascular disease is the leading cause of death among women; one-third of these deaths are directly or indirectly related to heart failure. Women already constitute the majority of heart failure patients and, given their longer life expectancy, the proportion of elderly women with heart failure is likely to increase further. These figures alone should make elderly women with heart failure a medical research and public health priority. On the contrary, they have received, and continue to receive, very little attention. Elderly women have been largely excluded from heart failure clinical trials and, compared with their male counterparts, are under-recognized and less intensively investigated and treated in clinical practice. Elderly women with heart failure are at increased risk for adverse outcomes because of higher comorbidity, psychological distress and socioeconomic disadvantage. Yet, they are often left alone to deal with these problems, which can negatively affect their ability to carry out basic self-care tasks.

Russian mortality trends in the early XXI century: official statistics data

From the second half of the XX century, cardiovascular disease (CVD) remains one of the main problems of the modern medicine. Over the last two decades, developed countries demonstrated a marked decrease in all-cause mortality and CVD mortality, in particular. InRussia, since the mid-1960s, all-cause mortality gradually increased, with the proportion of CVD deaths being over 50 %, which led to unparalleled high levels of national mortality. In 2009, the absolute number of CVD deaths was 1136661, or 1 case out of 1,8. In other words, 3114 Russian people die from CVD every day. From 2004, all-cause mortality, including CVD mortality, started to decline, and this tendency has continued until at least 2009, as demonstrated by the mortality rate of 801 per 100,000. However, the mortality levels are still higher than in the late 1980s. The authors analysed the CVD dynamics between 2003 (the highest levels) and 2009 inclusive, using the official national statistics data. The last few years demonstrated a positive tendency of declining mortality. In particular, the all-cause mortality (deaths per 100,000) decreased from1644,2 in2003 to1416,8 in2009 (by 13,8 %). CVD mortality decreased by 13,6 %, and more markedly mostly in working-age people (by 18,9 %). Therefore, in 2009, the number of lives saved due to the decreasing CVD mortality was 260741. Further studies will explain the recent mortality trends inRussia.

Regulation of K(ATP) channel by 17β-estradiol in pancreatic β-cells

ATP-sensitive potassium channels (K(ATP)) regulate electrical activity and insulin secretion in pancreatic β-cells. When glucose concentration increases, the [ATP]/[ADP] ratio rises closing K(ATP) channels, and the membrane potential depolarizes, triggering insulin secretion. This pivotal role of K(ATP) channels is used not only by glucose but also by neurotransmitters, hormones and other physiological agents to modulate electrical and secretory β-cell response. In recent years, it has been demonstrated that estrogens and estrogen receptors are involved in glucose homeostasis, and that they can modulate the electrical activity and insulin secretion of pancreatic β-cells. The hormone 17β-estradiol (E2), at physiological levels, is implicated in maintaining normal insulin sensitivity for β-cell function. Long term exposure to E2 increases insulin content, insulin gene expression and insulin release via the estrogen receptor α (ERα), while rapid responses to E2 can regulate K(ATP) channels increasing cGMP levels through the estrogen receptor β (ERβ) and type A guanylate cyclase receptor (GC-A). This review summarizes the main actions of 17β-estradiol on K(ATP) channels and the subsequent insulin release in pancreatic β-cells.

Impact of sex hormone metabolism on the vascular effects of menopausal hormone therapy in cardiovascular disease

Epidemiological studies have shown that cardiovascular disease (CVD) is less common in pre-menopausal women (Pre-MW) compared to men of the same age or post-menopausal women (Post-MW), suggesting cardiovascular benefits of estrogen. Estrogen receptors (ERs) have been identified in the vasculature, and experimental studies have demonstrated vasodilator effects of estrogen/ER on the endothelium, vascular smooth muscle (VSM) and extracellular matrix. Several natural and synthetic estrogenic preparations have been developed for relief of menopausal vasomotor symptoms. However, whether menopausal hormone therapy (MHT) is beneficial in postmenopausal CVD remains controversial. Despite reports of vascular benefits of MHT from observational and experimental studies, randomized clinical trials (RCTs), such as the Heart and Estrogen/progestin Replacement Study (HERS) and the Women's Health Initiative (WHI), have suggested that, contrary to expectations, MHT may increase the risk of CVD. These discrepancies could be due to agerelated changes in sex hormone synthesis and metabolism, which would influence the effective dose of MHT and the sex hormone environment in Post-MW. Age-related changes in the vascular ER subtype, structure, expression, distribution, and post-ER signaling pathways in the endothelium and VSM, along with factors related to the design of RCTs, preexisting CVD condition, and structural changes in the blood vessels architecture have also been suggested as possible causes of MHT failure in CVD. Careful examination of these factors should help in identifying the causes of the changes in the vascular effects of estrogen with age. The sex hormone metabolic pathways, the active versus inactive estrogen metabolites, and their effects on vascular function, the mitochondria, the inflammatory process and angiogenesis should be further examined. Also, the genomic and non-genomic effects of estrogenic compounds should be viewed as integrated rather than discrete responses. The complex interactions between these factors highlight the importance of careful design of MHT RCTs, and the need of a more customized approach for each individual patient in order to enhance the vascular benefits of MHT in postmenopausal CVD.

Ischaemic heart disease in women: are there sex differences in pathophysiology and risk factors? Position paper from the working group on coronary pathophysiology and microcirculation of the European Society of Cardiology

Cardiovascular disease (CVD) is the leading cause of death in women, and knowledge of the clinical consequences of atherosclerosis and CVD in women has grown tremendously over the past 20 years. Research efforts have increased and many reports on various aspects of ischaemic heart disease (IHD) in women have been published highlighting sex differences in pathophysiology, presentation, and treatment of IHD. Data, however, remain limited. A description of the state of the science, with recognition of the shortcomings of current data, is necessary to guide future research and move the field forward. In this report, we identify gaps in existing literature and make recommendations for future research. Women largely share similar cardiovascular risk factors for IHD with men; however, women with suspected or confirmed IHD have less coronary atherosclerosis than men, even though they are older and have more cardiovascular risk factors than men. Coronary endothelial dysfunction and microvascular disease have been proposed as important determinants in the aetiology and prognosis of IHD in women, but research is limited on whether sex differences in these mechanisms truly exist. Differences in the epidemiology of IHD between women and men remain largely unexplained, as we are still unable to explain why women are protected towards IHD until older age compared with men. Eventually, a better understanding of these processes and mechanisms may improve the prevention and the clinical management of IHD in women.