Gender differences in cardiovascular disease: hormonal and biochemical influences

The relationship between BMI and the prescription of anti-obesity medication according to social factors: a population cross sectional study

Background

Obesity is a global public health problem. There are a range of treatments available with varying short and long term success rates. One option is the use of anti-obesity medication the prescription of which has increased dramatically in recent years. Despite this, little is known about the individual and GP practice factors that influence the prescription of anti-obesity medication.

Methods

Multi-level logistic regression analysis was used to investigate factors associated with the prescription of anti-obesity medication in Northern Ireland using a population primary care prescribing database (~1.5 million people aged 16+ years) during 2009/10.

Results

While 25.0% of people are obese, only 1.3% (2.1% of females, 0.6% of males) received anti-obesity medication. The relationship between medication rates and age differed by gender (P < 0.001) with prescriptions higher in younger females and older males. Prescribing of anti-obesity medication reflected obesity prevalence across urban/rural areas and deprivation. There was an unexplained two-fold difference, between the 25^th and 75^th percentile, in the GP practice prescription of anti-obesity medication.

Conclusions

There is evidence of relative under-prescribing in males compared to females despite a similar prevalence of obesity. While the prevalence (and presumably the health consequences) of obesity worsens with age, younger females are more likely to be prescribed anti-obesity medication. This suggests an element of patient demand. Educational material to improve the understanding of the role of anti-obesity medication, for patients and practitioners, is recommended. But further study is needed to understand the factors responsible for the variation in prescribing between GP practices.

Adiposity rebound and the development of metabolic syndrome

OBJECTIVE

The age of adiposity rebound (AR) is defined as the time at which BMI starts to rise after infancy and is thought to be a marker of later obesity. To determine whether this age is related to future occurrence of metabolic syndrome, we investigated the relationship of the timing of AR with metabolic consequences at 12 years of age.

METHODS

A total of 271 children (147 boys and 124 girls) born in 1995 and 1996 were enrolled in the study. Serial measurements of BMI were conducted at the ages of 4 and 8 months and 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 years, based on which age of AR was calculated. Plasma lipids and blood pressure were measured at 12 years of age.

RESULTS

An earlier AR (<4 years of age) was associated with a higher BMI (≥ 20) and a lipoprotein phenotype representative of insulin resistance. This phenotype consists of elevated triglycerides, apolipoprotein B, and atherogenic index and decreased high-density lipoprotein cholesterol in boys and elevated apolipoprotein B in girls at 12 years of age. The earlier AR was also related to elevated blood pressure in boys.

CONCLUSIONS

This longitudinal population-based study indicates that children who exhibit AR at a younger age are predisposed to future development of metabolic syndrome. Therefore, monitoring of AR may be an effective method for the early identification of children at risk for metabolic syndrome.

Hypertension: what's sex got to do with it?

Hypertension is a complex and multifaceted disease, and there are well established sex differences in many aspects of blood pressure (BP) control. The intent of this review is to highlight recent work examining sex differences in the molecular mechanisms of BP control in hypertension to assess whether the "one-size-fits-all" approach to BP control is appropriate with regard to sex.

Coordination in gene expression during atherogenesis

General tendencies in the regulation of gene expression during atherogenesis were investigated using correlation analysis for 34 mRNA species of several functional groups. The contents of mRNA were measured by quantitative PCR in samples of human aortal intima containing no lesions or atherosclerotic lesions of types I (initial lesions), II (fatty streaks), and Va (fibroatheromas). The coupling between mRNA contents in lesions and the same mRNAs in intact tissue was found to descend in the course of the disease progression. The data are in accordance with the opinion that successive morphologic types of atherosclerotic lesions correspond to steps of atherogenesis. In addition, the contents of individual mRNA species could correlate with each other within the given sample type, the extent of this coupling rising along with the disease progression. The exception from this rule was a collapse in coupling for several functional groups of mRNA in lesions of type I. This collapse could indicate special position of these lesions in pathogenesis. Statistically significant correlations between mRNAs found in samples of all four types comprised in total about 50% of all possible correlations. 66% of these correlations were conservative, i.e. observed in at least two sample types. By coupling-strength, the studied mRNAs could be divided into four clusters whose composition significantly varied along with the disease progression. The disease progression was also associated with decline in number of regulatory factors that determine coordination in expression of the analyzed genes.

Lower zinc bioavailability may be related to higher risk of subclinical atherosclerosis in Korean adults

Background

There is a proposed link between dietary zinc intake and atherosclerosis, but this relationship remains unclear. Phytate may contribute to this relationship by influencing zinc bioavailability.

Objective

The aim of this study is to examine the relationship between zinc bioavailability and subclinical atherosclerosis in healthy Korean adults.

Materials and Methods

The present cross-sectional analysis used baseline data from the Korean multi-Rural Communities Cohort Study (MRCohort), which is a part of The Korean Genome Epidemiology Study (KoGES). A total of 5,532 subjects (2,116 men and 3,416 women) aged 40 years and older were recruited from rural communities in South Korea between 2005 and 2010. Phytate:zinc molar ratio, estimated from a food-based food frequency questionnaire (FFQ) of 106 food items, was used to determine zinc bioavailability, and carotid intima media thickness (cIMT) and pulse wave velocity (PWV) were measured to calculate the subclinical atherosclerotic index.

Results

We found that phytate:zinc molar ratio is positively related to cIMT in men. A higher phytate:zinc molar ratio was significantly related to an increased risk of atherosclerosis in men, defined as the 80^th percentile value of cIMT (5^th vs. 1^st quintile, OR = 2.11, 95% CI 1.42-3.15, P for trend = 0.0009), and especially in elderly men (5^th vs. 1^st quintile, OR = 2.58, 95% CI 1.52-4.37, P for trend = 0.0021). We found a positive relationship between phytate:zinc molar ratio and atherosclerosis risk among women aged 65 years or younger. Phytate:zinc molar ratio was not found to be related to PWV.

Conclusions

Lower zinc bioavailability may be related to higher atherosclerosis risk.

Metabolic disturbances and worsening of atherosclerotic lesions in ApoE-/- mice after cola beverages drinking

Background

Atherosclerosis is a major health burden. Metabolic disorders had been associated with large consumption of soft drinks. The rising incidence of atherosclerosis and metabolic alterations warrants the study of long-term soft drink consumption’ effects on metabolism and atherosclerosis in genetic deficiency of apolipoprotein E which typically develops spontaneous atherosclerosis and metabolic alterations.

Methods

ApoE^-/- mice were randomized in 3 groups accordingly with free access to: water (W), regular cola (C) or light cola (L). After 8 weeks, 50% of the animals in each group were euthanized (Treatment: W₈, C₈, L₈). The remaining mice (all groups) drank water for 8 weeks and were euthanized (Washout: W₁₆, C₁₆, L₁₆). Body weight and food and drink consumption were periodically measured. Blood was collected (biochemistry). At autopsy, transverse aortic sinus sections were serially cut and stained (histomorphometry); livers and kidneys were processed (microscopy). MANOVA (identification of variance factors) was followed by ANOVA and LSD tests (within-factor differences between levels). Conventionally a p< 0.05 was considered significant.

Results

Treatment increased drinking volumes (vs W₈: 4 fold C₈, p<0.0001; +47% L₈, p<0.02). Only C reduced eating amounts (–54%, p<0.05 vs W₈). I). Compared with W₈: C₈ developed hyperglycemia (+43%, p<0.03) and increased non-HDL cholesterol (+54%, p<0.05); L₈ showed decreased glycemia (–15%, p<0.05 vs W₈) and increased creatinine (2.5 fold, p<0.04), urea (+74, p<0.03) and aspartate-aminotransferase (2.8 fold, p<0.05). Hypercreatininemia was observed in L₁₆ (2.7 fold vs W₁₆, p<0.05). Hypertriglyceridemia (+91%, p<0.008) and hyperuremia (+68%, p<0.03) developed over time of study (age). II). Treatment caused plaque area increase (vs W₈: 28% C₈, p<0.02 and 50% L₈, p<0.01; vs W₁₆: 43% C₁₆, p<0.05 and 68% L₁₆, p<0.02) and stenosis (vs W₈: 38% C₈, p<0.04 and 57% L₈, p<0.01; vs W₁₆: 71% C₁₆, p<0.01 and 46% L₁₆, p<0.04). Age also caused plaque area increase (56%, p<0.04). Treatment- and age-effects on plaque enlargement were additive.

Conclusion

Cola beverages caused atherosclerotic lesions’ enlargement with metabolic (C) or non metabolic disturbances (L). ApoE^-/- mice were particularly sensitive to L treatment. These findings may likely relate to caramel colorant and non-nutritive sweeteners in cola drinks and have potential implications in particularly sensitive individuals.

Determinants of extraaortic arterial 18F-FDG accumulation in asymptomatic cohorts: sex differences in the association with cardiovascular risk factors and coronary artery stenosis

The objective of this study was to evaluate extraaortic arterial (18)F-FDG accumulation in asymptomatic cohorts by sex and to clarify the association between extraaortic arterial (18)F-FDG accumulation and cardiovascular risk factors (CRFs) and coronary artery stenosis (CAS).

METHODS

Five hundred twenty-one asymptomatic individuals (351 men and 170 women) who underwent cancer and CAS screening were enrolled. We evaluated extraaortic arterial (18)F-FDG accumulation in the carotid artery (CA) and iliofemoral artery (IFA) and classified the accumulation patterns into 3 types. Type 1 patients had no extraaortic arterial (18)F-FDG accumulation, type 2 had accumulation in either the CA or the IFA, and type 3 had accumulation in both the CA and IFA. CRFs (age, low-density lipoprotein [LDL] and high-density lipoprotein [HDL] cholesterol, triglyceride concentration, visceral abdominal fat, hypertension, diabetes, and smoking) and significant CAS were examined in relation to each accumulation type.

RESULTS

The men showed more extensive extraaortic arterial (18)F-FDG accumulation than the women. Type 3 accumulation (60.4% vs. 37.1%, P < 0.0001) was more frequently observed in men, whereas type 2 (34.2% vs. 44.7%, P = 0.02) and type 1 (5.4% vs. 18.2%, P < 0.0001) accumulation were more frequent in women. The CRFs other than smoking tended to be worse with extensive extraaortic arterial (18)F-FDG accumulation. A multivariate logistic regression analysis showed that hypertension, age, LDL cholesterol, triglyceride, and visceral abdominal fat were significantly associated with type 3 accumulation in men, and LDL cholesterol and HDL cholesterol (inversely) were significantly associated with type 3 accumulation in women. CAS was found in 4.2% (9/212) of male patients and in 1.6% (1/63) of female patients with type 3 accumulation, whereas no CAS was found in the other 2 types.

CONCLUSION

The men showed more extensive extraaortic arterial (18)F-FDG accumulation than the women. LDL cholesterol was associated with extensive extraaortic arterial (18)F-FDG accumulation in both sexes, but the other CRFs associated with extensive extraaortic (18)F-FDG arterial accumulation differed between the sexes. The type 3 accumulation was considered to pose a risk of CAS, especially in male patients, whereas non-type 3 accumulation presented little risk.

Endothelial function does not relate to haemoglobin or serum erythropoietin concentrations and these do not explain the gender difference in endothelial function in healthy middle-aged men and women

BACKGROUND

Haemoglobin scavenges nitric oxide, and a previous study has shown a negative association between flow-mediated vasodilation (FMD), a measure of nitric oxide (NO)-dependent vasomotor function and haemoglobin concentrations [Hb]. Circulating erythropoietin (EPO) is also negatively associated with [Hb] and could influence availability of NO. The purpose of this study was to examine the association of FMD with [Hb] and EPO concentrations and to determine whether these contribute to the sex difference in FMD. FMD (by high-resolution ultrasound), [Hb], circulating immunoreactive EPO and cardiovascular risk factors were measured in 317 healthy middle-aged men and women (183 women, 33 premenopausal, mean age ± SD, 55 ± 6·8 years) participating in a dietary study.

RESULTS

In the whole mixed-sex group, FMD was negatively correlated with [Hb] (R = -0·23, P < 0·001). However, in a multivariable model, incorporating sex and other confounding factors, FMD was independently negatively correlated only with age, male sex and systolic blood pressure: standardized regression coefficients -0·21 (P < 0·01), -0·17 (P < 0·05) and -0·20 (P < 0·05) respectively and not with [Hb]. Similarly, when the analysis was restricted to men or to postmenopausal women, there was no significant relationship between FMD and Hb. There was no significant correlation between FMD and EPO on either univariate analysis in the whole group, in each sex, or in multivariate analysis.

CONCLUSION

These results suggest that in healthy middle-aged subjects, FMD is not influenced by [Hb] or EPO and these do not contribute to the gender difference in FMD.

Sexual dimorphism in rodent models of hypertension and atherosclerosis

Approximately one third of all deaths are attributed to cardiovascular disease (CVD), making it the biggest killer worldwide. Despite a number of therapeutic options available, the burden of CVD morbidity continues to grow indicating the need for continued research to address this unmet need. In this respect, investigation of the mechanisms underlying the protection that premenopausal females enjoy from cardiovascular-related disease and mortality is of interest. In this review, we discuss the essential role that rodent animal models play in enabling this field of research. In particular, we focus our discussion on models of hypertension and atherosclerosis.

Angiotensin II type 2 receptor mediates sex differences in mice renal interlobar arteries response to angiotensin II

OBJECTIVE

Functional sex differences are described in several vascular beds. In the case of renal vessels, sex differences could influence processes like regulation of blood pressure and ion balance. Angiotensin II and nitric oxide are important regulators of renal vascular tone. Females have higher nitric oxide synthase expression, nitric oxide bioavailability and ratio of angiotensin II type 2/type 1 receptors. Thus, our objective was to examine whether renal interlobar arteries present sex differences in their response to angiotensin II, and whether angiotensin II type 2 receptors play a role in such differences.

METHODS

We investigated the isometric contraction and relaxation of interlobar arteries from female and male mice under blockade of nitric oxide synthases and angiotensin II type 2 receptors. We also investigated the expression of angiotensin II receptors (type 1 and 2) and endothelial nitric oxide synthase.

RESULTS

Significantly less intense contraction to angiotensin II were seen in arteries from females in comparison to male mice. Inhibition of nitric oxide synthases and endothelial removal abolished this difference. Angiotensin II type 2 receptors blockade enhanced contraction to angiotensin II in females, but not in males. Endothelial-dependent vasodilation was more dependent on nitric oxide in females than in males. Expression of angiotensin II type 1 and type 2 receptors was similar between sexes. Expression of endothelial nitric oxide synthase was higher in females.

CONCLUSION

A sex-specific, nitric oxide-mediated effect via angiotensin II type 2 receptors underlies the sex differences in the response of interlobar arteries to angiotensin II. Our findings may help understanding sex differences in renal hemodynamics and blood pressure control.

Microsatellite polymorphism in the fibrillin 3 gene and susceptibility to PCOS: a case-control study and meta-analysis

The D19S884 marker at the fibrillin 3 gene has been analysed as a candidate location for polycystic ovary syndrome (PCOS) mainly in Caucasian descendants. A case-control study was performed with 272 PCOS women and 271 controls to test the hypothesis that variants in the D19S884 marker increase susceptibility to PCOS in Chinese women and a meta-analysis was undertaken to clarify whether there is an allele consistently contributing to the susceptibility. The association analysis showed that PCOS women were significantly different from controls in the distribution of D19S884 allele frequencies. Instead of the well-known A8 allele, the most common allele in Chinese population was proved to be A7, and the allele frequencies of A7 were statistically different between cases and controls (P=0.037). The meta-analysis of A8 and A7 only identified A8 as a significant allelic association at the D19S884 marker in all combined samples (A8: OR 1.391, 95% CI 1.169-1.654; A7: OR 1.154, 95% CI 0.894-1.490). In conclusion, the association study showed a potential association of the D19S884 marker with PCOS in Chinese Han women and the meta-analysis identified that A8 may increase susceptibility to PCOS. Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, and it affects an estimated 15% of women worldwide based on the Rotterdam criteria. Many studies in Caucasian descendants suggested that variants of the D19S884 marker at the fibrillin 3 gene are associated with the risk of this syndrome. Here we performed a case-control study with 272 PCOS women and 271 controls to investigate whether variants in the D19S884 marker increase susceptibility to PCOS in Chinese women. We also carried out a meta-analysis of some relevant studies to find a more reliable result. Our association analysis showed that PCOS women were significantly different from controls in the distribution of D19S884 allele frequencies, and instead of the well-known A8 (the letter 'A' represents 'allele'), the most common allele in Chinese population was proved to be A7, whose allele frequencies were statistically different between cases and controls. The meta-analysis of A8 and A7 only identified A8 as a significant allelic association at the D19S884 marker in all combined samples. In conclusion, our association study showed a potential association of the D19S884 marker with PCOS in Chinese Han women and the meta-analysis identified that A8 may increase susceptibility to PCOS.

Early-life sex-dependent vulnerability to oxidative stress: the natural twining model

OBJECTIVES

Twins represent a unique natural model for studying fetal adaptation to a suboptimal supply of nutrients in utero, the most likely cause of reduced fetal growth, which has been associated with cardiovascular risk. The proposed developmental origin of cardiovascular diseases may offer new venues for investigating the molecular basis of the well-known gender disparity in cardiovascular disease pathogenesis and progression. Early sex differences in oxidative stress, a mechanism of injury associated with both reduced fetal growth and cardiovascular diseases, have been so far poorly investigated. Thus, we aimed at evaluating oxidative stress in newborn twins by measuring oxidative stress biomarkers in cord blood.

METHODS

Blood samples were collected from umbilical cord of 80 premature twins. The oxidative stress biomarker15-F(2t)-isoprostane and the total antioxidant capacity (tAOC) were measured in cord plasma.

RESULTS

Males had higher levels of plasma 15-F(2t)-isoprostane than females. 15-F(2t)-isoprostane values remained greater in males than in females when considering like-sex or unlike sex pairs. No difference was found in tAOC levels.

CONCLUSIONS

Our data suggest that sex-based differences in oxidant injury vulnerability occurring early in life could represent a biological mechanism contributing to gender disparity later in life.

Why sex matters: the biological mechanisms of cardiovascular disease

Cardiovascular disease (CVD) is the leading determinant of mortality and morbidity in women. However, a full understanding of the basic and clinical aspects of CVD in women is far from being accomplished. Sexual dimorphism in CVD has been reported both in humans and experimental animals. Menopause is a risk factor for CVD due to the reduction of endogenous estrogen, although the mechanisms underlying are poorly understood. Estrogens act through binding to vascular estrogen receptors and by non-genomic mechanisms. Advances in this field are essential to improve CVD diagnostic and clinical strategies in women, and to develop sex-specific prevention plans as much as female-oriented treatment algorithms. This paper reviews pathophysiology of CVD in women and its potential clinical implications. Particular emphasis is given to biochemical markers and to indicators of cardiovascular dysfunction and damage. Estimation of these parameters, central to cardiovascular pathophysiology, could represent a particularly relevant tool in female patients. More research is needed to identify women who will profit most of early intervention.

Recent developments in antiandrogens and selective androgen receptor modulators

The androgens testosterone and dihydrotestosterone play an essential role in the development and maintenance of primary and secondary male characteristics. Androgens bind to a specific androgen receptor (AR), a ligand-dependent transcription factor which controls the expression of a large number of downstream target genes. The AR is an essential player in early and late prostate cancer, and may also be involved in some forms of breast cancer. It also represents a drug target for the treatment of hypogonadism. Recent studies furthermore indicate that targeting the AR in pathologies such as frailty syndrome, cachexia or polycystic ovary syndrome may have clinical benefit. Numerous AR ligands with very different pharmacological properties have been identified in the last 40 years and helped to treat several of these diseases. However, progress still needs to be made in order to find compounds with an improved profile with regard to efficacy, differentiation and side-effects. This will only be achieved through a better understanding of the mechanisms involved in normal and aberrant AR signaling.

Sex differences and sex steroids in lung health and disease

Sex differences in the biology of different organ systems and the influence of sex hormones in modulating health and disease are increasingly relevant in clinical and research areas. Although work has focused on sex differences and sex hormones in cardiovascular, musculoskeletal, and neuronal systems, there is now increasing clinical evidence for sex differences in incidence, morbidity, and mortality of lung diseases including allergic diseases (such as asthma), chronic obstructive pulmonary disease, pulmonary fibrosis, lung cancer, as well as pulmonary hypertension. Whether such differences are inherent and/or whether sex steroids play a role in modulating these differences is currently under investigation. The purpose of this review is to define sex differences in lung structure/function under normal and specific disease states, with exploration of whether and how sex hormone signaling mechanisms may explain these clinical observations. Focusing on adult age groups, the review addresses the following: 1) inherent sex differences in lung anatomy and physiology; 2) the importance of certain time points in life such as puberty, pregnancy, menopause, and aging; 3) expression and signaling of sex steroid receptors under normal vs. disease states; 4) potential interplay between different sex steroids; 5) the question of whether sex steroids are beneficial or detrimental to the lung; and 6) the potential use of sex steroid signaling as biomarkers and therapeutic avenues in lung diseases. The importance of focusing on sex differences and sex steroids in the lung lies in the increasing incidence of lung diseases in women and the need to address lung diseases across the life span.

Circulating androgen levels are associated with subclinical atherosclerosis and arterial stiffness in healthy recently menopausal women

Although increasing evidence supports an association between endogenous sex hormones and cardiovascular disease, the results still remain controversial. This study aims to examine the association between endogenous sex hormones and indices of vascular function and structure. Serum follicle-stimulating hormone, luteinizing hormone, estradiol, testosterone, sex hormone-binding globulin, dehydroepiandrosterone sulfate (DHEAS), and Δ4-androstenedione were measured in 120 healthy postmenopausal women aged 41 to 60 years. Possible associations with surrogate markers of subclinical atherosclerosis, arterial stiffness, and endothelial function were investigated. Indices of arterial structure included carotid and femoral intima-media thickness and atheromatous plaques presence. Indices of arterial function included flow-mediated dilation of the brachial artery, carotid-femoral pulse wave velocity (PWV), and augmentation index. Total testosterone and free androgen index (FAI) were the most important predictors of common carotid artery intima-media thickness (β = 0.376 and β = 0.236, P < .001 and P = .014, respectively). Similarly, FAI was the only significant independent predictor of PWV (β = 0.254, P = .027) after adjusting for age, smoking, body mass index, homeostasis model assessment of insulin resistance, and blood lipids. Free estrogen index showed a positive association with PWV, independently of age, smoking, and body mass index, but not of homeostasis model assessment of insulin resistance and blood lipids. Age-adjusted levels of DHEAS exhibited a significant independent negative association with measures of augmentation index. Follicle-stimulating hormone, luteinizing hormone, estradiol, sex hormone-binding globulin, and Δ4-androstenedione were not associated with any of the vascular parameters independently of traditional cardiovascular risk factors. Higher serum testosterone and FAI are associated with subclinical atherosclerosis in healthy recently menopausal women. This association is independent of traditional cardiovascular risk factors or insulin resistance. On the contrary, serum DHEAS exhibits a negative association with arterial stiffness.

Effect of intravenous hydralazine infusion on maternal plasma nitric oxide levels in gestations complicated with severe preeclampsia: a pilot study

AIM

To investigate the effect of intravenous hydralazine infusion on maternal nitric oxide (NO) levels.

METHODS

This pilot study comprised 40 (n = 40) gestations complicated with severe preeclampsia to whom maternal plasma NO levels were determined by chemiluminescence before and after hydralazine administration. Blood pressure values were concomitantly assessed.

RESULTS

After 20 min of intravenous hydralazine infusion blood pressure values decrease significantly in term and preterm gestations. This was accompanied by an overall significant decrease in mean plasma NO values (38.7 ± 12.9 to 35.4 ± 13.9 μmol/L, p < 0.05). Despite this, NO values decreased in 67.5% of cases (a 17.6% from baseline) and increased in 32.5% (a 14.8% from baseline) (p < 0.05 for both). Blood pressure decrease (%) was lower (systolic and diastolic) among those displaying a NO decrement than in the increment group. Interestingly, gestational age was higher in the group displaying decreased NO; however, this did not reach statistical significance (37.5 ± 2.7 vs. 35.9 ± 2.8 weeks, p = 0.08).

CONCLUSION

The results of this study fail to demonstrate a similar NO secretion after hydralazine infusion in women with severe preeclampsia.

Pharmacology and clinical use of sex steroid hormone receptor modulators

Sex steroid receptors are ligand-triggered transcription factors. Oestrogen, progesterone and androgen receptors form, together with the glucocorticoid and mineralocorticoid receptors, a subgroup of the superfamily of nuclear receptors. They share a common mode of action, namely translating a hormone-i.e. a small-molecule signal-from outside to changes in gene expression and cell fate, and thereby represent "natural" pharmacological targets.For pharmacological therapy, these receptors have originally been addressed by hormones and synthetic hormone analogues in order to overcome pathologies related to deficiencies in the natural ligands. Another major use for female sex hormone receptor modulators is oral contraception, i.e. birth control.On the other side, blocking the activity of sex steroid receptors has become an established way to treat hormone-dependent malignancies, such as breast and prostate cancer.In this review, we will discuss how the experience gained from the classical pharmacology of these receptors and their molecular similarities led to new options for the treatment of gender-specific diseases and highlight recent progress in medicinal chemistry of sex hormone-modulating drugs.

Cardiovascular disease and ovarian function

PURPOSE OF REVIEW

Coronary heart disease (CHD) is the leading cause of death in the aging female population in the developed world. Ovarian endocrinology plays an important role in modulating a woman's CHD risk. We herein present an overview of our current understanding of CHD risk profile in the context of ovarian physiology and senescence.

RECENT FINDINGS

Endogenous ovarian estrogen has long been recognized to offer cardiac benefit and vascular protection against atherosclerosis. Existing data, however, do not allow for an extrapolation of the recognized cardioprotective implications of the reproductive-age endogenous estrogenic milieu to the use of exogenous estrogen in postmenopausal women. Ongoing efforts are targeting the concept that when reintroduced proximate to onset of ovarian senescence, exogenous estrogen may retard the process of atherogenesis. Until this hypothesis is substantiated, cardioprotection must not be an indication for initiating hormone therapy in menopausal women.

SUMMARY

Ovarian hormones modulate the processes of atherosclerosis and the mechanisms underlying CHD. The female reproductive hormones offer a cardioprotective milieu that is rapidly attenuated with the cessation of ovarian function (be it following natural menopause or after medical or surgical ovarian extirpation). The role of exogenous hormone therapy, and the nuances of timing and duration of exposure, are still being elucidated.

Effect of shiftwork on systemic markers of inflammation

Shiftwork is associated with an increased risk of cardiovascular diseases, but the possible role of inflammation in this relationship is not well known. We tested the hypothesis that shiftwork would be associated with higher levels of C-reactive protein (CRP) and increased leukocyte count. We analyzed the cross-sectional associations between work arrangements and low-grade inflammation in 1877 airline-company employees separately for men (n = 1037) and women (n = 840). The participants were classified into five categories according to their work schedule: day workers who have not worked in shifts (referent group), former shiftworkers, 2-shift workers, 3-shift workers, and in-flight workers. In models adjusted for age and recent infectious diseases, CRP levels were higher among male 3-shift workers (p = .002) and marginally higher in male 2-shift workers (p = .076). In addition, leukocyte count was higher in 2-shift (p = .005) and 3-shift (p = .021) working men. In women, CRP level was higher in 2-shift workers (p = .028), whereas leukocyte count was lower in flight workers (p = .005). Any separate adjustment additionally for smoking, education, alcohol consumption, physical activity, and obesity did not substantially affect the results of 2- and 3-shift work. In the fully adjusted model, only the association between 3-shift work and CRP in men (p = .021) and 2-shift work and leukocyte count in men (p = .020) and leukocyte count in 3-shift-working women (p = .044) were significant. Our results suggest that 2- and 3-shift work is associated with increased systemic inflammation and the relationship is relatively independent of the considered risk factors of cardiovascular disease.

Endothelial dysfunction in the apolipoprotein E-deficient mouse: insights into the influence of diet, gender and aging

Since the early 1990s, several strains of genetically modified mice have been developed as models for experimental atherosclerosis. Among the available models, the apolipoprotein E-deficient (apoE⁻/⁻) mouse is of particular relevance because of its propensity to spontaneously develop hypercholesterolemia and atherosclerotic lesions that are similar to those found in humans, even when the mice are fed a chow diet. The main purpose of this review is to highlight the key achievements that have contributed to elucidating the mechanisms pertaining to vascular dysfunction in the apoE⁻/⁻ mouse. First, we summarize lipoproteins and atherosclerosis phenotypes in the apoE⁻/⁻ mouse, and then we briefly discuss controversial evidence relative to the influence of gender on the development of atherosclerosis in this murine model. Second, we discuss the main mechanisms underlying the endothelial dysfunction of conducting vessels and resistance vessels and examine how this vascular defect can be influenced by diet, aging and gender in the apoE⁻/⁻ mouse.

Insulin-like growth factor I (IGF-1) deficiency ameliorates sex difference in cardiac contractile function and intracellular Ca(2+) homeostasis

Sex difference in cardiac contractile function exists which may contribute to the different prevalence in cardiovascular diseases between genders. However, the precise mechanisms of action behind sex difference in cardiac function are still elusive. Given that sex difference exists in insulin-like growth factor I (IGF-1) cascade, this study is designed to evaluate the impact of severe liver IGF-1 deficiency (LID) on sex difference in cardiac function. Echocardiographic, cardiomyocyte contractile and intracellular Ca(2+) properties were evaluated including ventricular geometry, fractional shortening, peak shortening, maximal velocity of shortening/relengthening (±dL/dt), time-to-peak shortening (TPS), time-to-90% relengthening (TR(90)), fura-fluorescence intensity (FFI) and intracellular Ca(2+) clearance. Female C57 mice exhibited significantly higher plasma IGF-1 levels than their male counterpart. LID mice possessed comparably low IGF-1 levels in both sexes. Female C57 and LID mice displayed lower body, heart and liver weights compared to male counterparts. Echocardiographic analysis revealed larger LV mass in female C57 but not LID mice without sex difference in other cardiac geometric indices. Myocytes from female C57 mice exhibited reduced peak shortening, ±dL/dt, longer TPS, TR(90) and intracellular Ca(2+) clearance compared with males. Interestingly, this sex difference was greatly attenuated or abolished by IGF-1 deficiency. Female C57 mice displayed significantly decreased mRNA and protein levels of Na(+)-Ca(2+) exchanger, SERCA2a and phosphorylated phospholamban as well as SERCA activity compared with male C57 mice. These sex differences in Ca(2+) regulatory proteins were abolished or overtly attenuated by IGF-1 deficiency. In summary, our data suggested that IGF-1 deficiency may significantly attenuated or mitigate the sex difference in cardiomyocyte contractile function associated with intracellular Ca(2+) regulation.

Pro-inflammatory cytokine levels in postmenopausal women with the metabolic syndrome

BACKGROUND

Prevalence of the metabolic syndrome (METS) and its components significantly increase after the menopause. Related increased cardiovascular risk may partially be explained by a pro-inflammatory state.

OBJECTIVE

To assess pro-inflammatory cytokine serum levels in postmenopausal women with and without the METS.

METHODS

Serum of 90 postmenopausal women who previously participated in a METS screening programme was analysed for tumour necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6). Cytokine levels were compared among those with and without the syndrome, and for each of its components. Linear relationships were also assessed between cytokine levels and several continuous variables including each diagnostic METS criteria and menopausal symptoms assessed with the Menopause Specific Quality of Life tool (MENQOL).

RESULTS

For all studied women mean age was 55.1 ± 7.3 years with 63.3% having abdominal obesity, 15.6% hyperglycaemia, 58.9% high triglycerides, 44.4% hypertension and 25.6% high total cholesterol levels. Women with the METS (n = 45) significantly had higher body mass index values, and higher rates of abdominal obesity, hyperglycaemia, hypertriglyceridemia, hypertension and lower HDL-C levels. Cytokine levels did not differ among women with or without the METS; however, independent of METS diagnosis those with abdominal obesity displayed significantly higher IL-6 levels and those with hypertension higher levels of both cytokines. Levels of both cytokines positively correlated with age and time since menopause, IL-6 positively correlating with waist circumference values and TNF-α positively with both systolic and diastolic blood pressure levels. A significant positive correlation was also found between the number of positive METS criteria (0-5) and both cytokine levels. Cytokine levels did not correlate with vasomotor and psycho-social MENQOL scores.

CONCLUSION

Pro-inflammatory cytokine levels in this postmenopausal series positively correlated with age, time since the menopause, abdominal circumference, blood pressures levels and the number of positive METS diagnostic criteria. There is a need for more research in this regard.

Prospective association of periodontal disease with cardiovascular and all-cause mortality: NHANES III follow-up study

BACKGROUND

It has been suggested that periodontal disease (PD) was associated with an increased risk for cardiovascular diseases (CVD), although evidence is inconclusive.

PURPOSE

We first sought to prospectively evaluate the relationship of PD to CVD and all-cause mortality using a national representative sample in the United States.

METHODS

The study population consisted of 10,849 participants who were 30 years or older and received a periodontal examination from NHANES III mortality follow-up sample (1988-2006). CVD and all-cause deaths were ascertained from the National Death Index records. The causes of death were defined using the International Classification of Disease coding (ICD-10). The severity of PD was categorized as non-PD, modest and severe PD based on clinical attachment loss and pocket depth.

RESULTS

Of the study sample, 3105 and 561 participants were identified as modest and severe PD cases, respectively. After up to 18 years of follow-up, there were total 2894 deaths, of which 1225 were from CVD. The levels of inflammation markers (high sensitivity C-reactive protein, white cell count and fibrinogen) were significantly higher in men with severe PD compared to men without PD (p<0.05). The prospective associations were evaluated using multivariable Cox proportional-hazards models. After adjusting for age, gender, race, household income and traditional risk factors of CVD, severe PD was associated with an increase risk of CVD mortality and all-cause mortality in men aged 30-64 years (HR=2.13 with 95% confidence interval of 1.37-3.31 for CVD mortality; HR=1.64 with 95% confidence interval of 1.25-2.15 for all-cause mortality). In addition, significant linear trends were found in CVD and all-cause mortality across the severity of PD (p<0.001). However, no significant associations were found in men aged ≥65 and in women.

CONCLUSIONS

There appears to be prospective associations between PD and CVD and all-cause mortality in men aged 30-64 years. Inflammation may be one possible pathway to link PD with CVD.

The relationship between pulse pressure and leukoaraiosis in the elderly

Leukaraiosis and a higher level of pulse pressure are well-recognized as associated with cardiovascular disease, vascular angiopathy, and geriatric syndrome. A cross-sectional study was conducted to examine the relation between pulse pressure and leukoaraiosis based on brain magnetic resonance imaging (MRI) scans in the apparently healthy elderly (147 men aged 60-84 years and 89 women aged 60-82 years). The odds ratios (OR) and 95% confidence interval (CI) for leukoaraiosis were calculated using multivariate logistic regression analyses according to each quartile of pulse pressure. The percentage of leukoaraiosis gradually increased in accordance with pulse pressure quartiles: 5.1%, 8.6%, 16.1%, and 26.2% for men, and 4.5%, 8.7%, 13.0%, and 23.8% for women. In comparison with subjects in the lowest quartile, the OR (95%CI) for leukoaraiosis in the highest quartile was 6.80 (1.20-38.45) in men after adjusting for age, body mass index, fasting plasma glucose, HDL-cholesterol, triglyceride (TG), smoking status, and current drinking. However, the relationship was not evident in women after adjusting for the same co-variables. In conclusion, pulse pressure was found to be independently associated with leukoaraiosis regardless of classical cardiovascular risk factors in elderly men.

Sex differences in lipid and lipoprotein metabolism: it's not just about sex hormones

It is commonly thought that sex hormones are important regulators of plasma lipid kinetics and are responsible for sexual dimorphism in the plasma lipid profile. Here we discuss the findings from studies evaluating lipid and lipoprotein kinetics in men and women in the context of what we know about the effects of exogenous sex hormone administration, and we conclude that it is more complicated than that. It has become clear that normal physiological alterations in the hormonal milieu (i.e. due to menopause or throughout the menstrual cycle) do not significantly affect plasma lipid homeostasis. Furthermore, parenterally administered estrogens have either no effect or only very small beneficial effects, whereas orally administered estrogens raise plasma triglyceride concentrations--a phenomenon that is not consistent with the observed sex differences and likely results from the hepatic "first-pass effect." The effects of progestogens and androgens mimic only in part the differences in plasma lipids between men and women. Thus, the underlying physiological modulators of plasma lipid metabolism responsible for the differences between men and women remain to be elucidated.

A higher burden of small low-density lipoprotein particles is associated with profound changes in the free androgen index in male adolescents

From a young age, males are at higher cardiovascular risk than females. Dyslipidemia, including a higher burden related to small low-density lipoproteins (LDL), plays an important role in precipitating atherosclerosis in both males and females. We investigated sex differences in atherogenic lipoprotein burden and the independent predictors of LDL particle size in children and adolescents. We measured the concentrations of total testosterone, sex hormone-binding globulin, estradiol, total cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, and LDL particle size in 135 children and adolescents (67 boys, 68 girls). The free androgen index was significantly and negatively correlated with LDL particle size (r = -0.273, P = 0.026) in boys, but estrogen and LDL particle size were not related. In a stepwise multiple regression analysis adjusted for body mass index, age, and homeostasis model assessment for insulin resistance, free androgen index was still an independent predictor of LDL particle size in boys (R(2) = 0.075, P = 0.026). The prominent decrease in LDL particle size along with increased testosterone concentrations in males might explain why they are more likely to display atherogenic dyslipidemia from adolescence.