Interleukin-6 and flow-mediated dilatation as markers of increased vascular inflammation in women receiving hormone therapy

Short-term administration of tibolone reduces inflammation and oxidative stress in the hippocampus of ovariectomized rats fed high-fat and high-fructose

Inflammation and oxidative stress are critical events involved in neurodegeneration. In animal models, it has been shown that chronic consumption of a hypercaloric diet, which leads to inflammatory processes, affects the hippocampus, a brain region fundamental for learning and memory processes. In addition, advanced age and menopause are risk factors for neurodegeneration. Hormone replacement therapy (HRT) ameliorates menopause symptoms. Tibolone (TB), a synthetic hormone, exerts estrogenic, progestogenic and androgenic effects on different tissues. We aimed to determine the effect of short-term TB administration on oxidative stress and inflammation markers in the hippocampus of ovariectomized rats fed a high-fat-and-fructose diet (HFFD). Adult female rats were ovariectomized (OVX) and fed standard diet or HFFD-consisting of 10% lard supplemented chow and 20% high-fructose syrup in the drinking water-and administered vehicle or TB (1 mg/kg for seven days). Finally, we administered hormone receptor antagonists (MPP, RU486 or FLU) to each of the OVX + HFFD + TB groups. Bodyweight, triglycerides and cholesterol, oxidative stress and inflammation markers, and the activity and expression of antioxidant enzymes were quantified in the hippocampus of each experimental group. We observed that short-term TB administration significantly reduced body weight, AGEs, MDA levels, increased SOD and GPx activity, improved GSH/GSSG ratio, and reduced IL-6 and TNF-α. Our findings suggest that short-term administration of TB decreases oxidative stress and reduces inflammation caused by HFFD and early estrogenic decline. These effects occurred via estrogen receptor alpha.

Sex Differences in the Inflammatory Response: Pharmacological Opportunities for Therapeutics for Coronary Artery Disease

Coordinated molecular responses are key to effective initiation and resolution of both acute and chronic inflammation. Vascular inflammation plays an important role in initiating and perpetuating atherosclerotic disease, specifically at the site of plaque and subsequent fibrous cap rupture. Both men and women succumb to this disease process, and although management strategies have focused on revascularization and pharmacological therapies in the acute situation to reverse vessel closure and prevent thrombogenesis, data now suggest that regulation of host inflammation may improve both morbidity and mortality, thus supporting the notion that prevention is better than cure. There is a clear sex difference in the incidence of vascular disease, and data confirm biological differences in inflammatory initiation and resolution between men and women. This article reviews contemporary opinions describing the sex difference in the initiation and resolution of inflammatory responses, with a view to explore potential targets for pharmacological intervention.

Effect of hormone replacement therapy with the anti-mineralocorticoid progestin Drospirenone compared to tibolone on endothelial function and central haemodynamics in post-menopausal women

Drospirenone (DRSP) is an antialdosterone agent with progestogenic and antiandrogenic effects. This compound, has been recently used in combination with 17β-estradiol (E2) as hormonal therapy in postmenopausal women and has been shown to exert a significant antihypertensive effect in hypertensive post-menopausal women. Aim of the present study was to compare the effect of DRSP/E2 with those of Tibolone (T) on endothelial function, arterial stiffness, and lipid profile of early postmenopausal women naïve on post-menopausal hormonal therapy. Twenty-four women met the inclusion criteria and entered the study. Women were randomized to receive either DRSP/E2 or T for 6months. Blood pressure and heart rate were similar in both groups at baseline and at the end of the study. Compared to baseline, endothelial function assessed by Reactive Hyperemia (RH) significantly improved in women receiving E2/DRSP, whereas no significant differences between baseline and follow up were detected in women receiving Tibolone. Women receiving E2/DRSP showed a significant decrease in pulse wave velocity and Augmentation Index compared to baseline while no changes were observed in women receiving Tibolone. The capacity of sera to trigger endothelial cells apoptosis in vitro measured by cell death assay was significantly reduced by E/DRSP but not by T (HFA-E 70±5,6% vs HFD-E 41±4,5%, p<0,001). In conclusion, the present study shows that the association of Estradiol and Drospirenone as hormonal replacement therapy significantly improves vascular parameters and the composition of sera relevant for vascular protection in early post-menopausal normotensive women. These effects are not shared by Tibolone.

C-reactive protein, interleukin-6, soluble tumor necrosis factor α receptor 2 and incident clinical depression

BACKGROUND

Despite an extensive literature on the role of inflammation and depression, few studies have evaluated the association between inflammatory biomarkers and depression in a prospective manner, and results are inconclusive.

METHODS

We conducted a prospective analysis of blood levels of CRP, IL-6 and TNFα-R2 in 4756 women participating in the Nurses׳ Health Study who donated blood in 1990 and were depression-free up to 1996. Participants were followed between 1996 and 2008 for reports of clinical diagnosis depression or antidepressant use. Additionally, we conducted cross-sectional analyses for CRP, IL-6 and TNFα-R2 and antidepressant use at time of blood draw.

RESULTS

After adjustment for body mass index, menopause status, use of anti-inflammatory drugs and other covariates, no significant associations between CRP, IL-6 and TNFα-R2 and incident depression were observed after a follow-up of 6-18 years. However, menopause status appears to modify the association between IL-6 and depression risk. In cross-sectional analyses, TNFα-R2 was associated with antidepressant use (OR=1.96, 95% CI=1.23-3.13, P-trend=0.001), but no significant associations were found for CRP and IL-6.

LIMITATIONS

Depression diagnosis was first assessed in 1996, 6 years after blood draw. However the biomarkers have high within-person correlations with measurements 4 years apart.

CONCLUSIONS

Blood levels of CRP, IL-6 and TNFα-R2 were not associated with incident depression over a follow-up of 6-18 years. In cross-sectional analyses, antidepressant use may be associated with higher levels of TNFα-R2 but no associations with depression or antidepressant use were observed in the prospective analysis.

The role of cytokines in skin aging

Cutaneous aging is one of the major noticeable menopausal complications that most women want to fight in their quest for an eternally youthful skin appearance. It may contribute to some maladies that occur in aging which, despite not being life-threatening, affect the well-being, psychological state and quality of life of aged women. Skin aging is mainly affected by three factors: chronological aging, decreased levels of estrogen after menopause, and environmental factors. Aged skin is characterized by a decrease in collagen content and skin thickness which result in dry, wrinkled skin that is easily bruised and takes a longer time to heal. Cytokines play a crucial role in the manifestation of these features of old skin. The pro-inflammatory cytokine tumor necrosis factor-alpha inhibits collagen synthesis and enhances collagen degradation by increasing the production of MMP-9. It also lowers the skin immunity and thus increases the risk of cutaneous infections in old age. Deranged levels of several interleukins and interferons also affect the aging process. The high level of CCN1 protein in aged skin gives dermal fibroblasts an 'age-associated secretory phenotype' that causes abnormal homeostasis of skin collagen and leads to the loss of the function and integrity of skin. Further research is required especially to establish the role of cytokines in the treatment of cutaneous aging.

The role of cytokines in cardiovascular disease in menopause

Various studies suggest that increased levels of pro-inflammatory cytokines play a key role in the declining ovarian function and the resulting complications associated with menopause. In this review article, the authors outline the role of pro- and anti-inflammatory cytokines in cardiovascular disease during menopause.

Hormones, heart disease, and health: individualized medicine versus throwing the baby out with the bathwater

It is increasingly axiomatic that depression has widespread adverse physiological effects and, conversely, that a variety of physiological systems impact the risk for developing depression. This convergence of depression and altered physiology is particularly dramatic during midlife--a time during which reproductive failure presages dramatic increases in prevalence of both heart disease and depression. The potentially meaningful and illuminating links between estrogen deficiency, cardiovascular disease (CVD), and depression have largely been obscured, first by assertions, subsequently repudiated, that the perimenopause was not a time of increased risk of depression, and more recently by the denegration of hormone replacement therapy by initial reports of the Women's Health Initiative. Increasingly, however, research has led to unavoidable conclusions that CVD and depression share common, mediating pathogenic processes and that these same processes are dramatically altered by the presence or absence of estrogen (E2). This review summarizes data supporting these contentions with the intent of placing depression and estrogen therapy in their proper physiologic context.

Hormones, heart disease, and health: individualized medicine versus throwing the baby out with the bathwater

It is increasingly axiomatic that depression has widespread adverse physiological effects, and conversely that a variety of physiological systems impact the risk for developing depression. This convergence of depression and altered physiology is particularly dramatic during midlife-a time during which reproductive failure presages dramatic increases in prevalence of both heart disease and depression. The potentially meaningful and illuminating links between estrogen (E2) deficiency, cardiovascular disease (CVD), and depression have largely been obscured, first by assertions, subsequently repudiated that the perimenopause was not a time of increased risk of depression, and more recently by the denegration of hormone replacement therapy by initial reports of the Women's Health Initiative. Increasingly, however, research has led to unavoidable conclusions that CVD and depression share common and mediating pathogenic processes and that these same processes are dramatically altered by the presence or absence of E2. This review summarizes data supporting this contention with the intent of placing depression and E2 therapy in their proper physiologic context.

Effects of menopause and tibolone on different cardiovascular biomarkers in healthy women

BACKGROUND AND AIM

The effects of tibolone on cardiovascular risk is not yet fully understood today. We designed this study to assess the effect of the menopausal status and tibolone treatment (2.5 mg/day for 3 months) on different biomarkers of cardiovascular risk in healthy women.

METHODS

Blood arterial pressure were measured, and blood samples collected for glucose, lipid profile (total cholesterol, high density lipoproteins, HDL, low density lipoproteins, and triglycerides), inflammatory (C-reactive protein, Interleukin-6, IL-6, tumor necrosis factor alpha, TNF alpha) and oxidative stress (hydroperoxides and antioxidant capacity) evaluation in 15 premenopausal (mean age: 30 +/- 4 years) and 15 postmenopausal (mean age: 52 +/- 3, mean time from menopause 1.4 +/- 0.4 years) women before and after tibolone treatment.

RESULTS

The menopausal status is associated with increased systolic and diastolic pressure (p<0.05), higher IL-6 (p<0.05) and TNF alpha (p<0.01), and lower antioxidants (p<0.01). However, blood pressure (p<0.05), glucose (p<0.05), TNF alpha (p<0.05) and HDL (p<0.05) fell after tibolone, which did not significantly affect levels of the other biochemical parameters.

CONCLUSIONS

As menopause is associated with increased blood pressure, inflammation and oxidative stress, tibolone restores blood pressure and has beneficial effect on inflammation and glycemia without worsening oxidative stress, although it also reduces HDL levels. Such modifications should be taken into account when tailoring menopausal therapies to specific requirements of each woman.

Risk Factors for Heart Attack, Stroke, and Venous Thrombosis Associated With Hormonal Contraceptive Use

The search for a safe and effective method of contraception has been ongoing for centuries. During the last century, a variety of hormonal contraceptives, including combined hormonal oral contraceptives (COCs), have been introduced into the market. COCs have evolved through modifications of different hormonal components to minimize the risk of thrombotic events including stroke, myocardial infarction, and venous thrombosis. The evolution of COC development led to the reduction in the estrogen dose, in an attempt to lower the risk of vascular diseases. Although the risk of thrombotic events due to COC use has been substantially reduced since their inception, the quest for developing safer methods of birth control continues. It is of great interest to study coagulation effects of newer COCs, as well as progestin only, as rigorously as older COCs.

To assess, to control, to exclude: effects of biobehavioral factors on circulating inflammatory markers

Behavioral scientists have increasingly included inflammatory biology as mechanisms in their investigation of psychosocial dynamics on the pathobiology of disease. However, a lack of standardization of inclusion and exclusion criteria and assessment of relevant control variables impacts the interpretation of these studies. The present paper reviews and discusses human biobehavioral factors that can affect the measurement of circulating markers of inflammation. Keywords relevant to inflammatory biology and biobehavioral factors were searched through PubMed. Age, sex, and hormonal status, socioeconomic status, ethnicity and race, body mass index, exercise, diet, caffeine, smoking, alcohol, sleep disruption, antidepressants, aspirin, and medications for cardiovascular disease are all reviewed. A tiered set of recommendations as to whether each variable should be assessed, controlled for, or used as an exclusion criteria is provided. These recommendations provide a framework for observational and intervention studies investigating linkages between psychosocial and behavioral factors and inflammation.

Hormone replacement therapy and cardioprotection: a new dawn? A statement of the Study Group on Cardiovascular Disease in Women of the Italian Society of Cardiology on hormone replacement therapy in postmenopausal women

Cardiovascular disease is the leading cause of death in women in Western countries. Despite preventive strategies, in the past decades the incidence of cardiovascular events has shown a decline in men but a rise in women, matching the growth of the population of postmenopausal women. Several epidemiological findings suggest the causative pathophysiological role of ovarian hormone deficiency in the development of cardiovascular disease in women. Observational and randomized studies have suggested that hormone replacement therapy in early postmenopause could be beneficial from a cardiovascular point of view. Conversely, aging, time since menopause and presence of cardiovascular risk factors or cardiovascular disease may decrease its efficacy and increase the risk of cardiovascular events. It is plausible that the unfavorable effects of the estrogen/progestin combination used in the randomized studies are not related to the hormone preparation per se but rather to the use of hormones in the less receptive group of women, older and with cardiovascular risk factors. Clinical judgment, choice of the right dose and estrogen/progestin combination are of pivotal importance to maximize the beneficial effect of estrogen replacement therapy/hormone replacement therapy, especially if given within a reasonable time after the menopause to women who need the therapy for the relief of menopausal symptoms.

Effects of estradiol and raloxifene on arterial thrombosis in ovariectomized mice

OBJECTIVE

The effects of estrogen and selective estrogen receptor modulators (eg, raloxifene) on arterial thrombosis are not well defined. This study assessed the manner and mechanism by which estrogen and raloxifene affect homeostatic pathways in ovariectomized mice after acute arterial injury.

DESIGN

Female mice (3 weeks old) underwent ovariectomy or sham operation. Five days after surgery, mice were assigned to treatment with estradiol (5.3 nmol/kg), raloxifene (2.7 micromol/kg), or placebo (n = 10-12/group). The biological effects of both treatments were assessed by measurements of bone mass and the degree of uterine atrophy. After 4 months of therapy, carotid artery thrombosis was induced by photochemical injury, and the time to vascular occlusion was measured.

RESULTS

Both treatments increased bone mineral density (4.1%-7.85%). Reversal of macroscopic uterine atrophy was observed only in estrogen-treated mice. Ovariectomized mice had a shorter time to occlusion compared with sham-operated mice (70.8 +/- 7.4 vs 103 +/- 11.3 min), suggesting accelerated thrombosis. Both estradiol and raloxifene significantly inhibited intra-arterial thrombosis in ovariectomized mice, prolonging the time to occlusion to 136.33 +/- 13.5 and 141.43 +/- 9.26 min, respectively. Cyclooxygenase-2 levels in the lung tissue were significantly increased by both raloxifene and estradiol with endothelial nitric oxide synthase expression being unaltered. Platelet adhesion (measured by surface coverage under a shear rate of 1,800 s for 2 min) was significantly reduced in ovariectomized animals, being 4.63% +/- 1.47%, 5.78% +/- 1.58%, and 10.04% +/- 1.33% for raloxifene, estradiol, and placebo, respectively.

CONCLUSIONS

Ovariectomy amplifies thrombosis. We found that 4 months of treatment with both estradiol and raloxifene attenuates intravascular thrombosis. The antithrombotic effect was accompanied by increased expression of cyclooxygenase-2 and suppression of platelet surface adhesion.

Combined continuous ethinyl estradiol/norethindrone acetate does not improve forearm blood flow in postmenopausal women at risk for cardiovascular events: a pilot study

OBJECTIVE

This study sought to determine whether combined continuous ethinyl estradiol and norethindrone acetate, a postmenopausal hormone therapy (HT) combination designed to have fewer side effects than cyclical therapies and therapies using medroxyprogesterone acetate (MPA), could improve vascular endothelial function in postmenopausal women with risk factors for cardiovascular disease (CVD).

METHODS

Eighteen postmenopausal women (mean age 62 +/- 11 years) participated in a randomized, placebo-controlled, crossover design trial of 10 microg estradiol/1 mg norethindrone acetate given once daily for 3 months, with a 1-month washout period between placebo and active treatment phases. Vascular reactivity was assessed at each phase of the study using high-frequency brachial artery ultrasound in response to flow-mediated hyperemia, cold pressor testing, and sublingual nitroglycerin. Markers of cardiovascular risk, including cholesterol levels, inflammatory markers, fibrinolytic markers, and solubilized adhesion molecules, were also measured at each phase.

RESULTS

We found no significant difference in vascular reactivity measurements during active treatment with ethinyl estradiol/norethindrone acetate vs. placebo. C-reactive protein (CRP) levels increased significantly during active treatment, and high-density lipoprotein (HDL) levels decreased significantly. Vascular cell adhesion molecule-1 (VCAM-1) levels declined during active treatment. Plasminogen activator inhibitor-1 (PAI-1) levels were inversely correlated with flow-mediated hyperemic vascular reactivity, independent of active treatment or placebo phases.

CONCLUSIONS

In this older postmenopausal population with at least one cardiovascular risk factor, treatment with combined continuous ethinyl estradiol and norethindrone acetate failed to improve vascular endothelial function. The agent's proinflammatory effect or subclinical atherosclerosis in this population may have contributed to this finding.

Hormonal and nutritional effects on cardiovascular risk markers in young women

CONTEXT

Cardiovascular (CV) risk markers, including high-sensitivity C-reactive protein (hsCRP), are increasingly important in predicting cardiac events. A favorable CV risk profile might be expected in anorexia nervosa (AN) due to low body weight and dietary fat intake. However, women with AN have decreased IGF-I levels reflecting decreased GH action, and IGF-I deficiency is associated with elevated hsCRP. Moreover, oral estrogens, known to increase hsCRP in other populations, are commonly prescribed in AN. To date, hsCRP levels and their physiological determinants have not been reported in women with AN.

OBJECTIVE

We examined the relationship between CV risk markers, undernutrition, IGF-I, and oral estrogens, specifically hypothesizing that in the setting of undernutrition, AN would be associated with low hsCRP despite low IGF-I levels and that those women taking oral contraceptive pills (OCPs) would have higher hsCRP and lower IGF-I levels.

DESIGN AND SETTING

We conducted a cross-sectional study at a clinical research center.

STUDY PARTICIPANTS

Subjects included 181 women: 140 women with AN [85 not receiving OCPs (AN-E) and 55 receiving OCPs (AN+E)] and 41 healthy controls [28 not receiving OCPs (HC-E) and 13 receiving OCPs (HC+E)].

MAIN OUTCOME MEASURES

We assessed hsCRP, IL-6, IGF-I, low-density lipoprotein (LDL), and high-density lipoprotein (HDL).

RESULTS

Despite low weight, more than 20% of AN+E had high-risk hsCRP levels. AN+E had higher hsCRP than AN-E. AN-E had lower mean hsCRP levels than healthy controls (HC+E and HC-E). IL-6 levels were higher in AN+E with elevated hsCRP (>3 mg/liter) than in AN+E with normal hsCRP levels. IGF-I was inversely associated with hsCRP in healthy women, suggesting a protective effect of GH on CV risk. However, this was not seen in AN. Few patients in any group had high-risk LDL or HDL levels.

CONCLUSIONS

Although hsCRP levels are lower in AN than healthy controls, OCP use puts such women at a greater than 20% chance of having hsCRP in the high-CV-risk (>3 mg/liter) category. The elevated mean IL-6 in women with AN and high-risk hsCRP levels suggests that increased systemic inflammation may underlie the hsCRP elevation in these patients. Although OCP use in AN was associated with slightly lower mean LDL and higher mean HDL, means were within the normal range, and few patients in any group had high-risk LDL or HDL levels. IGF-I levels appear to be important determinants of hsCRP in healthy young women. In contrast, IGF-I does not appear to mediate hsCRP levels in AN.

Cardiovascular health and the menopause: the gynecologist as the patients' interface

The large decrease in estrogen following menopause appears to explain the dramatic increase in cardiovascular disease (CVD) in postmenopausal women. Gynecologists are well placed to play a primary role in the diagnosis, prevention and management of CVD in these patients; this role may include advice on lifestyle changes, and, if appropriate, prescribing preventative treatments such as hormone replacement therapy (HRT) and lipid-lowering drugs. The use of estrogen replacement therapy (ERT) to prevent CVD is supported by a number of observational studies. However, recently, large, randomized trials gave unexpected, conflicting data on the cardiovascular benefits of HRT, leading to confusion, and influencing both patient and clinical perceptions regarding the role of HRT postmenopause. These different outcomes may be due to differences in the HRT regimens, mean age and mean time from menopause at enrollment, duration of therapy, and patient selection bias in observational studies. A 'unified hypothesis' consistent with findings from all studies has now been developed: HRT initiated at the time of the menopause prevents CVD, whereas HRT initiated years after the menopause seems to increase CHD events. This knowledge is essential for gynecologists making clinical decisions regarding HRT use.

Cellular mechanisms underlying the cardiovascular actions of oestrogens

Although pre-menopausal women enjoy relative cardiovascular protection, hormone (oestrogen±progestin)-replacement therapy has not shown cardiovascular benefits in post-menopausal women, suggesting that the effects of oestrogens on the cardiovascular system are much more complex than previously expected. Endothelial cells, smooth muscle cells, cardiac myocytes and fibroblasts, the cellular components of blood vessels and the heart, play important roles in cardiovascular health and disease. During the development and progression of cardiovascular disease, changes occur both in the structure and function of these cells, resulting in a wide range of abnormalities, which affect growth, death and physiological function. These cells contain functional oestrogen receptors and are targets for oestrogen action. This review focuses on recent studies on the effects of oestrogen on cardiovascular cell function. Oestrogens, particularly 17β-oestradiol, exert multiple effects on cardiovascular cells, and these effects may contribute to the gender-associated protection against cardiovascular diseases.

Sex dimorphism in cardiac pathophysiology: experimental findings, hormonal mechanisms, and molecular mechanisms

The higher cardiovascular risk in men and post-menopausal women implies a protective action of estrogen. A large number of experimental studies have provided strong support to this concept. However, the recent clinical trials with negative outcomes regarding hormone replacement therapy call for "post hoc" reassessment of existing information, models, and research strategies as well as a summary of recent findings. Sex steroid hormones, in particular estrogen, regulate numerous processes that are related to the development and progression of cardiovascular disease through a variety of signaling pathways. Use of genetically modified models has resulted in interesting information on diverse actions mediated by steroid receptors. By focusing on experimental findings, we have reviewed hormonal, cellular, and signaling mechanisms responsible for sex dimorphism and actions of hormone replacement therapy and addressed current limitations and future directions of experimental research.