Hormone replacement therapy may prevent the development of isolated pulmonary hypertension in patients with systemic sclerosis and limited cutaneous involvement

Effects of Hormone Replacement Therapy on Women's Lung Health and Disease

This review provides an overview of menopausal hormone therapy and pulmonary disease risk, with a focus on the effect of hormone replacement therapy (HRT) on pulmonary function and its relation to lung diseases. This summary is based on authors' knowledge in the field of HRT and supplemented by a PubMed search using the terms "menopause hormone therapy," "asthma", "lung cancer", "chronic obstructive pulmonary disease", "lung function", and "pulmonary hypertension". Available evidence indicates that there is limited research on the role of sex hormones in the susceptibility, severity, and progression of chronic respiratory diseases. However, some studies suggest that the hormonal changes that occur during the menopausal transition may have an impact on pulmonary function and respiratory diseases. Women are in need of convenient access to a safe and effective modality for personalized HRT based on an artificial intelligence (AI)-driven platform that will enable them to receive personalized hormonal treatment through frequent, convenient, and accurate measurements of hormone levels in peripheral blood.

Challenges of caring for transgender and gender diverse patients with rheumatic disease: presentation of seven patients and review of the literature

PURPOSE OF REVIEW

As perspectives on sex and gender identity have evolved, there has been an increase in the practice of transgender medicine. Within rheumatology, however, there is a dearth of information about rheumatic disease in transgender and gender diverse (TGGD) individuals. This is important, as sex hormones affect the etiopathogenesis and expression of autoimmune diseases. We therefore sought to identify TGGD patients with rheumatic disease, review their clinical courses, and appraise existing literature about this population.

RECENT FINDINGS

Of 1053 patients seen at the Los Angeles County and University of Southern California Medical Center from 2019 through 2021, five transgender men and two transgender women with rheumatic disease were identified. Most patients' disease courses were not overtly impacted by gender affirming hormone therapy (GAHT). Six of seven patients had psychosocial barriers to care. Our systematic review found 11 studies with 11 transgender women and two transgender men. In 12 of 13 patients, GAHT possibly modulated the patients' rheumatic disease.

SUMMARY

Our observations suggest GAHT need not be a strict contraindication in TGGD patients with rheumatic disease. TGGD patients often face significant psychosocial barriers. Additional information about this population and empathy toward their health disparities are needed.

Pathogenetic rationale for prescribing menopausal hormone therapy for systemic sclerosis

Systemic scleroderma (SS) is characterized by dysregulation of the innate and adaptive immune systems, vasculopathy, and generalized fibrosis. As with most autoimmune diseases, women predominate among patients, who get sick 3–14 times more often than men. It is assumed that gender differences and modulation of sex hormones are essential in the pathogenesis of SS. Estrogens are able to influence the immune response, have a vasodilating effect and stimulate the synthesis of collagen in the skin. The development of SS leads to a significant decrease in the quality of life, psychological disorders associated with changes in appearance, as well as the need for lifelong medication with the frequent development of side effects. Age-related estrogen deficiency associated with the onset of menopause is accompanied by a decrease in the quality of life and, in some cases, a change in the clinical manifestations of somatic diseases. This review considers the impact of menopause and menopausal hormone therapy (MHT) on the course and clinical manifestations of systemic scleroderma. It is noted that SS in some cases is accompanied by an early onset of menopause. The use of MHT is not associated with the progression of cutaneous fibrosis, and may also improve the vascular manifestations of SS.

Sex Differences in Pulmonary Hypertension

Pulmonary hypertension (PH) includes multiple diseases that share as common characteristic an elevated pulmonary artery pressure and right ventricular involvement. Sex differences are observed in practically all causes of PH. The most studied type is pulmonary arterial hypertension (PAH) which presents a gender bias regarding its prevalence, prognosis, and response to treatment. Although this disease is more frequent in women, once affected they present a better prognosis compared to men. Even if estrogens seem to be the key to understand these differences, animal models have shown contradictory results leading to the birth of the estrogen paradox. In this review we will summarize the evidence regarding sex differences in experimental animal models and, very specially, in patients suffering from PAH or PH from other etiologies.

Evaluation of Sex Hormone Levels in Patients with Pemphigus Vulgaris in Comparison to the Healthy Population

Materials and Methods

This cross-sectional study was performed on patients with pemphigus vulgaris referred to Faghihi Hospital and Shiraz Dental Faculty in 2017-2018. The participants included 26 women with histopathologically confirmed pemphigus vulgaris and 26 healthy age-matched controls. The serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estrogen, progesterone, testosterone, prolactin, dehydroepiandrosterone (DHEA), and dihydrotestosterone (DHT) were evaluated in both groups. Independent t-test and two-way ANOVA were used for data analysis.

Results

The mean age of the patients was 49.88 ± 10.46 years and that of the control group was 49.92 ± 11.30 years. Unlike the case group, the DHEA serum level was significantly higher among nonmenopausal participants in the control group. Moreover, the levels of testosterone and DHEA were significantly lower in the case group in comparison to the control group (p = 0.015 and p = 0.026, respectively).

Conclusion

Considering the effects of age and menopause, the serum levels of testosterone and DHEA were significantly lower in the patients with pemphigus vulgaris than in the healthy controls. Hence, these hormones might have a role in the pathogenesis of pemphigus vulgaris.

Gender-related differences in systemic sclerosis

Systemic sclerosis (SSc) is a complex autoimmune connective tissue disease which is characterised by autoimmunity, widespread tissue fibrosis of the skin and internal organs, and vasculopathic alterations. SSc is more common in women but has a more severe expression of disease including internal organ-based complications and higher mortality in men. The extant literature shows that although important pathophysiological sex differences are present in SSc, behavioural differences (e.g. higher smoking rates in men) and occupational exposures may contribute to poorer outcomes in men with SSc. The higher death male death rate in the general population and greater prevalence of lung fibrosis are likely the key factors responsible for excess mortality found in men. Other important factors include (but are not limited to) a greater prevalence of the disease subset, delayed time to diagnosis, and higher disease activity in early disease in men. SSc carries a significant burden of disease-related morbidity; however, no qualitative studies to date have focussed on gender differences in SSc. The purpose of this review is to provide a comprehensive overview of gender differences in SSc including (but not limited to) epidemiology, pathophysiology, clinical expression of disease, mortality, SSc in transgender individuals, and psychosocial aspects of disease.

Contribution of Sex and Autoantibodies to Microangiopathy Assessed by Nailfold Videocapillaroscopy in Systemic Sclerosis: A Systematic Review of the Literature

Objective

Microangiopathy and dysregulation of the immune system play important roles in the pathogenesis of systemic sclerosis (SSc). Factors that trigger vascular injury in SSc have not been elucidated so far. We undertook this study to evaluate whether sex or expression of specific antinuclear autoantibodies might associate with the degree of microangiopathy through performance of a systematic review that summarizes what is known about these associations.

Methods

A standardized search of PubMed, Embase, Web of Science, and the Cochrane Library were performed to identify studies that described autoantibodies in SSc patients and microangiopathy and, for the second search, those that described sex and microangiopathy.

Results

We included 11 studies that described the relationship between SSc‐specific autoantibodies and microangiopathy and 6 studies that reported on the association between sex and microangiopathy. Contradictory results were found on the association between SSc‐specific autoantibodies and microangiopathy, and no association was found between sex and microangiopathy based on the current literature.

Conclusion

Based on this review of the literature, we can conclude that sex does not seem to influence degree of microangiopathy in SSc, while results on association between SSc‐specific autoantibodies and degree of microangiopathy were inconclusive.

Sex, Gender, and Sex Hormones in Pulmonary Hypertension and Right Ventricular Failure

Pulmonary hypertension (PH) encompasses a syndrome of diseases that are characterized by elevated pulmonary artery pressure and pulmonary vascular remodeling and that frequently lead to right ventricular (RV) failure and death. Several types of PH exhibit sexually dimorphic features in disease penetrance, presentation, and progression. Most sexually dimorphic features in PH have been described in pulmonary arterial hypertension (PAH), a devastating and progressive pulmonary vasculopathy with a 3-year survival rate <60%. While patient registries show that women are more susceptible to development of PAH, female PAH patients display better RV function and increased survival compared to their male counterparts, a phenomenon referred to as the "estrogen paradox" or "estrogen puzzle" of PAH. Recent advances in the field have demonstrated that multiple sex hormones, receptors, and metabolites play a role in the estrogen puzzle and that the effects of hormone signaling may be time and compartment specific. While the underlying physiological mechanisms are complex, unraveling the estrogen puzzle may reveal novel therapeutic strategies to treat and reverse the effects of PAH/PH. In this article, we (i) review PH classification and pathophysiology; (ii) discuss sex/gender differences observed in patients and animal models; (iii) review sex hormone synthesis and metabolism; (iv) review in detail the scientific literature of sex hormone signaling in PAH/PH, particularly estrogen-, testosterone-, progesterone-, and dehydroepiandrosterone (DHEA)-mediated effects in the pulmonary vasculature and RV; (v) discuss hormone-independent variables contributing to sexually dimorphic disease presentation; and (vi) identify knowledge gaps and pathways forward. © 2020 American Physiological Society. Compr Physiol 10:125-170, 2020.

The Role of Sex in the Pathophysiology of Pulmonary Hypertension

Pulmonary arterial hypertension (PAH) is a progressive disease characterised by increased pulmonary vascular resistance and pulmonary artery remodelling as result of increased vascular tone and vascular cell proliferation, respectively. Eventually, this leads to right heart failure. Heritable PAH is caused by a mutation in the bone morphogenetic protein receptor-II (BMPR-II). Female susceptibility to PAH has been known for some time, and most recent figures show a female-to-male ratio of 4:1. Variations in the female sex hormone estrogen and estrogen metabolism modify FPAH risk, and penetrance of the disease in BMPR-II mutation carriers is increased in females. Several lines of evidence point towards estrogen being pathogenic in the pulmonary circulation, and thus increasing the risk of females developing PAH. Recent studies have also suggested that estrogen metabolism may be crucial in the development and progression of PAH with studies indicating that downstream metabolites such as 16α-hydroxyestrone are upregulated in several forms of experimental pulmonary hypertension (PH) and can cause pulmonary artery smooth muscle cell proliferation and subsequent vascular remodelling. Conversely, other estrogen metabolites such as 2-methoxyestradiol have been shown to be protective in the context of PAH. Estrogen may also upregulate the signalling pathways of other key mediators of PAH such as serotonin.

Diagnosing and managing scleroderma-related pulmonary arterial hypertension

Scleroderma is an uncommon autoimmune disease of unknown cause that may affect any organ system in the body. Patients with scleroderma are prone to developing pulmonary complications, including pulmonary arterial hypertension (PAH), that are the leading cause of death in this population. This article describes scleroderma-related PAH and its diagnosis and management.

Impact of Pituitary-Gonadal Axis Hormones on Pulmonary Arterial Hypertension in Men

The association of sex hormone (estradiol, testosterone, and progesterone) with cardiopulmonary disease has already attracted great attention, especially in pulmonary arterial hypertension (PAH). However, the impact of sex hormones and their pituitary stimulators (follicle-stimulating hormone and luteinizing hormone) on PAH in men remains unclear. We conducted a prospective cohort study recruiting 95 patients with idiopathic PAH from 2008 to 2014 and following up for a median of 65 months for death. Compared with control, abnormal plasma levels of sex hormones were more common in patients with PAH. Higher estradiol and estradiol/testosterone levels were associated with risk of PAH diagnosis (odds ratio per ln estradiol, 3.55; P<0.001; odds ratio per ln estradiol/testosterone, 4.30; P<0.001), whereas higher testosterone and progesterone were associated with a reduced risk (odds ratio per ln testosterone, 0.48; P=0.003; odds ratio per ln progesterone, 0.09; P<0.001). Fifty patients died during follow-up. Men with higher estradiol had increased mortality (hazard ratio per ln estradiol, 2.02; P=0.007), even after adjustment for baseline characteristics and PAH treatment. According to receiver operating characteristic analysis, patients with PAH with higher estradiol level (≥145.55 pmol/L) had worse 5-year survival rate compared with those with lower estradiol (38.6% versus 68.2%; log-rank test P=0.001). Therefore, our data show higher estradiol, estradiol/testosterone ratio, lower testosterone, and progesterone were associated with increased risk of PAH. Meanwhile, higher estradiol was independently associated with higher mortality in men with PAH. Further studies are needed to explain the origin of these hormonal derangements and their potential pathophysiological implications in PAH.

Sex differences in pulmonary arterial hypertension: role of infection and autoimmunity in the pathogenesis of disease

Registry data worldwide indicate an overall female predominance for pulmonary arterial hypertension (PAH) of 2–4 over men. Genetic predisposition accounts for only 1–5% of PAH cases, while autoimmune diseases and infections are closely linked to PAH. Idiopathic PAH may include patients with undiagnosed autoimmune diseases based on the relatively high presence of autoantibodies in this group. The two largest PAH registries to date report a sex ratio for autoimmune connective tissue disease-associated PAH of 9:1 female to male, highlighting the need for future studies to analyze subgroup data according to sex. Autoimmune diseases that have been associated with PAH include female-dominant systemic sclerosis, systemic lupus erythematosus, rheumatoid arthritis, Sjögren’s syndrome, and thyroiditis as well as male-dominant autoimmune diseases like myocarditis which has been linked to HIV-associated PAH. The sex-specific association of PAH to certain infections and autoimmune diseases suggests that sex hormones and inflammation may play an important role in driving the pathogenesis of disease. However, there is a paucity of data on sex differences in inflammation in PAH, and more research is needed to better understand the pathogenesis underlying PAH in men and women. This review uses data on sex differences in PAH and PAH-associated autoimmune diseases from registries to provide insight into the pathogenesis of disease.

Menopause and Rheumatic Disease

Menopause occurs naturally in women at about 50 years of age. There is a wealth of data concerning the relationship of menopause to systemic lupus erythematosus, rheumatoid arthritis, and osteoarthritis; there are limited data concerning other rheumatic diseases. Age at menopause may affect the risk and course of rheumatic diseases. Osteoporosis, an integral part of inflammatory rheumatic diseases, is made worse by menopause. Hormone replacement therapy has been studied; its effects vary depending on the disease and even different manifestations within the same disease. Cyclophosphamide can induce early menopause, but there is underlying decreased ovarian reserve in rheumatic diseases.

Severe pulmonary hypertension in aging female apolipoprotein E-deficient mice is rescued by estrogen replacement therapy

Background

Apolipoprotein E (ApoE) is a multifunctional protein, and its deficiency leads to the development of atherosclerosis in mice. Patients with pulmonary hypertension (PH) have reduced expression of ApoE in lung tissue. ApoE is known to inhibit endothelial and smooth muscle cell proliferation and has anti-inflammatory and anti-platelet aggregation properties. Young ApoE-deficient mice have been shown to develop PH on high fat diet. The combined role of female sex and aging in the development of PH has not been investigated before. Here, we investigated the development of PH in young and middle-aged (MA) female ApoE-deficient mice and explored the role of exogenous estrogen (E2) replacement therapy for the aging females.

Methods

Wild type (WT) and ApoE-deficient female mice (Young and MA) were injected with a single intraperitoneal dose of monocrotaline (MCT, 60 mg/kg). Some ApoE-deficient MA female mice that received MCT were also treated with subcutaneous E2 pellets (0.03 mg/kg/day) from day 21 to 30 after MCT injection. Direct cardiac catheterization was performed terminally to record right ventricular systolic pressure (RVSP). Right ventricular (RV), left ventricular (LV), and interventricular septum (IVS) were dissected and weighed. Lung sections were examined using trichrome and immunofluorescence staining. Western blot analyses of lung and RV lysates were performed.

Results

In WT female mice, the severity of PH was similar between young and MA mice as RVSP was not significantly different (RVSP = 38.2 ± 1.2 in young vs. 40.5 ± 8.3 mmHg in MA, p < 0.05). In ApoE-deficient mice, MA females developed significantly severe PH (RVSP = 63 ± 10 mmHg) compared to young females (RVSP; 36 ± 3 mmHg, p < 0.05 vs. MA female). ApoE-deficient MA females also developed more severe RV hypertrophy compared to young females (RV hypertrophy index (RV/[LV + IVS]) = 0.53 ± 0.06 vs. 0.33 ± 0.01, p < 0.05). ApoE-deficient MA female mice manifested increased peripheral pulmonary artery muscularization and pulmonary fibrosis. E2 treatment of MA female ApoE-deficient mice resulted in a significant decrease in RVSP, reversal of pulmonary vascular remodeling, and RV hypertrophy. In MA female ApoE-deficient mice with PH, only the expression of ERβ in the lungs, but not in RV, was significantly downregulated, and it was restored by E2 treatment. The expression of ERα was not affected in either lungs or RV by PH. GPR30 was only detected in the RV, and it was not affected by PH in MA female ApoE-deficient mice.

Conclusions

Our results suggest that only aging female ApoE-deficient but not WT mice develop severe PH compared to younger females. Exogenous estrogen therapy rescued PH and RV hypertrophy in aging female ApoE-deficient mice possibly through restoration of lung ERβ.

Risk factors for development of pulmonary arterial hypertension in Australian systemic sclerosis patients: results from a large multicenter cohort study

BACKGROUND

Pulmonary arterial hypertension (PAH) is the leading cause of mortality in patients with systemic sclerosis (SSc). We sought to determine the incidence, prevalence and risk factors for PAH development in a large Australian SSc cohort.

METHODS

PAH was diagnosed on right heart catheterisation (mPAP >25 and PAWP <15 mmHg at rest). Patients with PH secondary to interstitial lung disease (ILD; defined as abnormal HRCT scan and FVC < 60 %) were excluded. Summary statistics, chi-square tests, univariate and multivariable logistic regression along with post-estimation diagnostics were used to determine the associations of different combinations of risk factors with PAH.

RESULTS

Among 1579 SSc patients, 8.4 % (132 patients) were diagnosed with PAH over a mean (±SD) follow-up of 3.2 (±2.5) years. The incidence of PAH in this cohort was 0.7 % per annum. Of these, 68.9 % had limited disease subtype (lcSSc). In multivariable regression analysis, the presence of anti-centromere antibody (ACA) (OR 1.6, 95 % CI 1.1-2.5, p = 0.03), oesphageal stricture (OR 2.0, 95 % CI 1.2-3.3, p = 0.006), calcinosis (OR 1.9, 95 % CI 1.2-2.9, p = 0.003), sicca symptoms (OR 1.6, 95 % CI 1.1-2.5, p = 0.03), mild ILD (OR 2.3, 95 % CI 1.5-3.7, p < 0.001) and digital ulcers (OR 1.6, 95 % CI 1.0-2.4, p = 0.03) were predictive of PAH. This model had an area under the curve of 0.7 and concordance of 91.8 %. When analysed by disease subtype, the presence of calcinosis (OR 2.2, 95 % CI 1.4-3.7, p = 0.01), sicca symptoms (OR 2.6, 95 % CI 1.5-4.6, p = 0.001), mild ILD (OR 2.3, 95 % CI 1.4-3.8, p = 0.001) and digital ulcers (OR 1.9, 95 % CI 1.2-3.7, p = 0.01) were predictive of PAH in lcSSc; and oesophageal stricture (OR 4.4, 95 % CI 1.9-10.5, p = 0.001), mild ILD (OR 2.8, 95 % CI 1.2-6.8, p = 0.02) and ACA (OR 5.2, 95 % CI 1.8-14.8, p = 0.002) were predictive of PAH in dcSSc.

CONCLUSIONS

The incidence and prevalence of PAH in this cohort are 0.7 % per annum and 8.4 %, respectively. The clinical-serologic risk factors for PAH differ based on disease subtype. In both subtypes, mild ILD is associated with PAH, suggesting the possibility of common pathogenic mechanisms underlying both of these disease manifestations. This model identifies a subset of patients at an appreciably higher risk of developing PAH, who should be screened and would in future, benefit from preventative therapies.

Sex and menopause differences in response to tadalafil: 6-minute walk distance and time to clinical worsening

Pulmonary arterial hypertension (PAH) is a female-predominant disease, but there are little data on treatment response by sex and menopausal status. In this retrospective analysis of the Pulmonary Arterial Hypertension and Response to Tadalafil (PHIRST) randomized clinical trial, we assessed treatment response between the sexes by examining change in 6-minute walk distance (6MWD) and time to clinical worsening (TCW). We examined the effect of menopausal status on the same treatment measures. 6MWD was recorded before and after 16 weeks of treatment with tadalafil or placebo in the PHIRST study cohort of 340 subjects (264 females, 76 males). A univariate analysis was used to assess the effect of sex on change in 6MWD and TCW. Multivariate linear regression and Cox proportional hazards models were built for 6MWD and TCW, respectively. Women were subdivided by age as a surrogate for menopausal status. The linear trend test and the log-rank test were performed on change in 6MWD and TCW by age. For tadalafil-treated patients, a significant difference in change in 6MWD by sex (mean: 48.6 m for males vs. 34.7 m for females; P = 0.01) was found, but it was not significant in multivariate analysis (P = 0.08). There was a trend toward a female age-dependent effect in change in 6MWD; the premenopausal group showed the greatest improvement. A significant sex- or age-dependent effect on TCW was not present. In conclusion, this retrospective analysis of the PHIRST trial suggests that men and premenopausal women may experience greater functional improvement when treated with tadalafil than older women, but there was no consistent sex or menopausal effect on TCW.

Rheumatic autoimmune diseases in women and midlife health

Autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and systemic sclerosis (scleroderma) preferentially affect women, and are characterized by systemic inflammation leading to target organ dysfunction. The public health burden of autoimmune diseases, which collectively represent a leading cause of morbidity and mortality among women throughout adulthood, is substantial. While some features of these diseases have been observed to improve over the menopausal transition, such as disease flare rate in SLE and skin softening and thinning in scleroderma, others, such as swollen and tender joints and radiographically confirmed damage in RA may worsen. The general trends, however, are not consistent or conclusive for all disease-related manifestations. Of great importance is the recognition that comorbid diseases, including osteoporosis and accelerated cardiovascular disease, contribute excess morbidity and mortality that becomes increasingly apparent as women with autoimmune diseases undergo the menopausal transition.

Monitoring and Diagnostic Approaches for Pulmonary Arterial Hypertension in Patients with Systemic Sclerosis

Pulmonary arterial hypertension (PAH) is one of the leading causes of death in patients with systemic sclerosis (SSc). Given the high prevalence and poor survival of SSc-PAH, and that aggressive management of mild disease may be associated with better outcomes, screening is critical. Right heart catheterization (RHC) is the gold standard for the definitive diagnosis of PAH, and should be performed in those patients in whom this diagnosis is suspected. Once a diagnosis of PAH is confirmed by RHC, treatment with PAH-specific therapies should be initiated as soon as possible.

Safety of hormonal replacement therapy and oral contraceptives in systemic lupus erythematosus: a systematic review and meta-analysis

Background

There is conflicting data regarding exogenous sex hormones [oral contraceptives (OC) and hormonal replacement therapy (HRT)] exposure and different outcomes on Systemic Lupus Erythematosus (SLE). The aim of this work is to determine, through a systematic review and meta-analysis the risks associated with estrogen use for women with SLE as well as the association of estrogen with developing SLE.

Methods and Findings

MEDLINE, EMBASE, SciElo, BIREME and the Cochrane library (1982 to July 2012), were databases from which were selected and reviewed (PRISMA guidelines) randomized controlled trials, cross-sectional, case-control and prospective or retrospective nonrandomized, comparative studies without language restrictions. Those were evaluated by two investigators who extracted information on study characteristics, outcomes of interest, risk of bias and summarized strength of evidence. A total of 6,879 articles were identified; 20 full-text articles were included. Thirty-two meta-analyses were developed. A significant association between HRT exposure (Random model) and an increased risk of developing SLE was found (Rate Ratio: 1.96; 95%-CI: 1.51–2.56; P-value<0.001). One of eleven meta-analyses evaluating the risk for SLE associated with OC exposure had a marginally significant result. There were no associations between HRT or OC exposure and specific outcomes of SLE. It was not always possible to Meta-analyze all the available data. There was a wide heterogeneity of SLE outcome measurements and estrogen therapy administration.

Conclusion

An association between HRT exposure and SLE causality was observed. No association was found when analyzing the risk for SLE among OC users, however since women with high disease activity/Thromboses or antiphospholipid-antibodies were excluded from most of the studies, caution should be exercised in interpreting the present results. To identify risk factors that predispose healthy individuals to the development of SLE who are planning to start HRT or OC is suggested.

Gender differences in autoimmune disease

Autoimmune diseases are a range of diseases in which the immune response to self-antigens results in damage or dysfunction of tissues. Autoimmune diseases can be systemic or can affect specific organs or body systems. For most autoimmune diseases there is a clear sex difference in prevalence, whereby females are generally more frequently affected than males. In this review, we consider gender differences in systemic and organ-specific autoimmune diseases, and we summarize human data that outlines the prevalence of common autoimmune diseases specific to adult males and females in countries commonly surveyed. We discuss possible mechanisms for sex specific differences including gender differences in immune response and organ vulnerability, reproductive capacity including pregnancy, sex hormones, genetic predisposition, parental inheritance, and epigenetics. Evidence demonstrates that gender has a significant influence on the development of autoimmune disease. Thus, considerations of gender should be at the forefront of all studies that attempt to define mechanisms that underpin autoimmune disease.

Progress in solving the sex hormone paradox in pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with marked morbidity and mortality. Even though being female represents one of the most powerful risk factors for PAH, multiple questions about the underlying mechanisms remain, and two "estrogen paradoxes" in PAH exist. First, it is puzzling why estrogens have been found to be protective in various animal models of PAH, whereas PAH registries uniformly demonstrate a female susceptibility to the disease. Second, despite the pronounced tendency for the disease to develop in women, female PAH patients exhibit better survival than men. Recent mechanistic studies in classical and in novel animal models of PAH, as well as recent studies in PAH patients, have significantly advanced the field. In particular, it is now accepted that estrogen metabolism and receptor signaling, as well as estrogen interactions with key pathways in PAH development, appear to be potent disease modifiers. A better understanding of these interactions may lead to novel PAH therapies. It is the purpose of this review to 1) review sex hormone synthesis, metabolism, and receptor physiology; 2) assess the context in which sex hormones affect PAH pathogenesis; 3) provide a potential explanation for the observed estrogen paradoxes and gender differences in PAH; and 4) identify knowledge gaps and future research opportunities. Because the majority of published studies investigated 17β-estradiol and/or its metabolites, this review will primarily focus on pulmonary vascular and right ventricular effects of estrogens. Data for other sex hormones will be discussed very briefly.

Epidemiology and risk factors for pulmonary hypertension in systemic sclerosis

Systemic sclerosis (SSc) is a systemic autoimmune disease characterized by vasculopathy and excessive collagen production leading to fibrosis of the skin and internal organs. SSc patients are at risk of developing pulmonary hypertension (PH), a debilitating, progressive condition of the pulmonary vasculature that leads to right heart failure and death. This review is an updated summary of the epidemiology and risk factors for PH in SSc. We describe the current literature examining the incidence, prevalence, and demographic and clinical risk factors associated with PH in SSc. We also discuss classical and novel autoantibodies and potential biomarkers that may be helpful in the assessment of risk and prognosis of PH in SSc patients. The ultimate objective in understanding the risk of developing PH in SSc is early diagnosis and early initiation of appropriate therapy with the hope for improved outcomes for patients with SSc-PH.

Estradiol promotes the development of a fibrotic phenotype and is increased in the serum of patients with systemic sclerosis

INTRODUCTION

Systemic sclerosis (SSc) is more prevalent in women. Our goal is to determine the effects of 17β-estradiol (E2) on the development of fibrosis and to compare circulating levels of estrogens in SSc patients and healthy controls.

METHODS

Using primary human dermal fibroblasts, we evaluated the effect of E2 on fibronectin (FN) expression with and without the estrogen receptor (ER) antagonist ICI 182,780, inhibitors of signaling, propyl-pyrazole-triol, an ERα specific ligand, and genistein, an ERβ selective ligand, to identify the signaling pathways mediating E2's effect. We confirmed the fibrotic effect of E2 in human skin using an ex vivo organ culture model. Lastly, we measured levels of E2 and estrone in serum samples from SSc patients with diffuse cutaneous involvement and healthy controls using mass spectrometry.

RESULTS

E2 increased expression of FN in dermal fibroblasts. ICI 182,780, inositol-1,4,5-triphosphate inhibitor, and p38 mitogen-activated protein kinase inhibitor blocked the effects of E2 on FN. Propyl-pyrazole-triol, but not genistein, significantly increased FN expression. Ex vivo, E2 induced fibrosis of human skin. The effects of E2 were abrogated by ICI 182,780. Circulating levels of E2 and estrone were significantly increased in sera of patients with diffuse cutaneous SSc.

CONCLUSION

Our findings implicate estrogens in the fibrotic process and may explain the preponderance of SSc in women. ICI 182,780 or other ER signaling antagonists may be effective agents for the treatment of fibrosis.

Estrogen paradox in pulmonary hypertension: current controversies and future perspectives

Although the incidence of pulmonary hypertension is higher in female patients, numerous experimental studies have demonstrated better outcome in female animals, exacerbation of the disease after ovariectomy, and a strong protective effect of estrogen: a phenomenon known as the "estrogen paradox" of pulmonary hypertension. On the other hand, some clinical studies have indirectly linked estrogen to increased risk of portopulmonary hypertension, whereas others implicate increased estrogen metabolism and high levels of certain estrogen metabolites in promoting pulmonary vascular remodeling in familial pulmonary arterial hypertension. In this review we investigate the estrogen paradox through highlighting the differential receptor-mediated effects of estrogen. Although estrogen and estrogen receptor-based therapies have shown promise in rescuing preexisting pulmonary hypertension in animals, their role is yet to be defined in humans.

Ovarian stimulation and embryo banking for fertility preservation in a woman with severe mixed connective tissue disease: Is it safe?

OBJECTIVE

To report the first case of using assisted reproductive technologies (ART) for fertility preservation in a patient with mixed connective tissue disease (MCTD), secondary pulmonary hypertension (PH) and antiphospholipid syndrome (APS).

DESIGN

Case-report and review of the literature.

SETTING

Academic infertility practice and tertiary care center.

PATIENT(S)

A 25-year-old woman with MCTD, complicated with PH and APS, who was scheduled for gonadotoxic therapy

INTERVENTION(S)

Controlled ovarian hyperstimulation, egg retrieval, embryo banking.

MAIN OUTCOME MEASURE(S)

Successful ART cycle leading to embryo banking without worsening her underlying disease.

RESULT(S)

Following successful embryo cryopreservation, the patient experienced respiratory failure and other severe complications, resulting in a prolonged hospital stay.

CONCLUSION(S)

Controlled ovarian hyperstimulation for embryo banking in women with MCTD, PH and APS may pose a risk for potentially catastrophic complications. A multidisciplinary approach to these patients is necessary to optimize the outcomes of such procedures. More data are needed regarding the safety of fertility preservation technologies in patients with complex medical diseases.

Estrogen rescues preexisting severe pulmonary hypertension in rats

RATIONALE

Pulmonary hypertension (PH) is characterized by progressive increase in pulmonary artery pressure leading to right ventricular (RV) hypertrophy, RV failure, and death. Current treatments only temporarily reduce severity of the disease, and an ideal therapy is still lacking.

OBJECTIVES

Estrogen pretreatment has been shown to attenuate development of PH. Because PH is not often diagnosed early, we examined if estrogen can rescue preexisting advanced PH.

METHODS

PH was induced in male rats with monocrotaline (60 mg/kg). At Day 21, rats were either treated with 17-β estradiol or estrogen (E2, 42.5 μg/kg/d), estrogen receptor-β agonist (diarylpropionitrile, 850 μg/kg/d), or estrogen receptor α-agonist (4,4',4"-[4-Propyl-(1H)-pyrazole-1,3,5-triyl] trisphenol, 850 μg/kg/d) for 10 days or left untreated to develop RV failure. Serial echocardiography, cardiac catheterization, immunohistochemistry, Western blot, and real-time polymerase chain reaction were performed.

MEASUREMENTS AND MAIN RESULTS

Estrogen therapy prevented progression of PH to RV failure and restored lung and RV structure and function. This restoration was maintained even after removal of estrogen at Day 30, resulting in 100% survival at Day 42. Estradiol treatment restored the loss of blood vessels in the lungs and RV. In the presence of angiogenesis inhibitor TNP-470 (30 mg/kg) or estrogen receptor-β antagonist (PHTPP, 850 μg/kg/d), estrogen failed to rescue PH. Estrogen receptor-β selective agonist was as effective as estrogen in rescuing PH.

CONCLUSIONS

Estrogen rescues preexisting severe PH in rats by restoring lung and RV structure and function that are maintained even after removal of estrogen. Estrogen-induced rescue of PH is associated with stimulation of cardiopulmonary neoangiogenesis, suppression of inflammation, fibrosis, and RV hypertrophy. Furthermore, estrogen rescue is likely mediated through estrogen receptor-β.

Pulmonary hypertension in women

Female predominance in pulmonary arterial hypertension (PAH) has been known for several decades and recent interest in the effects of sex hormones on the development of disease has substantially increased our understanding of this epidemiologic observation. Basic science data suggest a beneficial effect of estrogens in the pulmonary vasculature both acutely and chronically, which seems to contradict the known predilection in women. Recent human and rodent data have suggested that altered levels of estrogen, differential signaling and altered metabolism of estrogens in PAH may underlie the gender difference in this disease. Studies of the effects of sex hormones on the right ventricle in animal and human disease will further aid in understanding gender differences in PAH. This article focuses on the effects of sex hormones on the pulmonary vasculature and right ventricle on both a basic science and translational level.

The estrogen paradox in pulmonary arterial hypertension

Idiopathic pulmonary arterial hypertension (PAH) is a disabling condition characterized by PA vasoconstriction and remodeling as well as in situ thrombosis and eventual right heart failure. Idiopathic PAH occurs more frequently in females than in males. The female:male ratio is 1.64 ∼ 3.88:1. Although endogenous sex hormones including estrogen have been suggested to account for the observed gender differences in PAH, a precise pathobiology for the gender differences remains uncertain. Recent studies demonstrated that estrogen exerts beneficial effects on the pulmonary vasculature. However, it seems to contradict the female predominance that is observed in idiopathic PAH. Moreover, Sweeney and Voelkel (Sweeney L and Voelkel NF. Eur J Med Res 14: 433-442, 2009) showed that early and long-term estrogen exposure might be correlated with an increased risk of the development of PAH. Here we ask the question: Is estrogen a friend or a foe? According to accumulating evidence, we postulate that the different effects of estrogens on different target cells could account for this paradox, i.e., estrogens may exert beneficial effects only on the increased muscularization of vessel walls, but not on phenotypically altered endothelial cells. The effects of estrogens on the pulmonary vasculature are potent and complex, yet not fully understood. A better mechanistic understanding may allow for future therapeutic interventions in patients with PAH.

Development of pulmonary arterial hypertension in women: interplay of sex hormones and pulmonary vascular disease

Pulmonary arterial hypertension (PAH) is a progressive disease of the pulmonary vasculature, ultimately resulting in right heart failure and death. This disease is strongly predominant in females, although little is known regarding how sex influences disease development. Recent developments highlighting the importance of estrogen metabolites in both animal models and human disease have substantially increased our understanding of PAH in women. This review will focus on general knowledge of PAH, translational and basic science data regarding sex hormones in the pulmonary vasculature and on clinical issues that are particular to women with PAH. Future directions for study include the influence of sex hormones on right ventricular responses, improving the understanding of the influence of estrogen exposure in human disease and the study of dehydroepiandrosterone in basic science and human disease.

2-methoxyestradiol attenuates bleomycin-induced pulmonary hypertension and fibrosis in estrogen-deficient rats

Pulmonary hypertension (PH) is a common and life-threatening complication of pulmonary fibrosis. Estradiol (E2) is protective in experimental PH, and its non-estrogenic metabolite 2-methoxyestradiol (2ME) prevents the development and retards the progression of monocrotaline-induced PH in male and female rats. However, the effects of E2 and 2ME on pulmonary fibrosis and associated PH have not been examined. Therefore, we compared the growth inhibitory effects of E2 and 2ME in human lung fibroblasts (hLFs) and pulmonary vascular smooth muscle cells (hPASMCs), and we investigated the effects of estrogen deficiency and 2ME on bleomycin-induced pulmonary fibrosis and PH. Intact and ovariectomized (OVX) female Sprague-Dawley rats were administered intratracheally either saline or bleomycin (15IU/kg), and a subset of OVX bleomycin-treated rats received 2ME (10microg/kg/h) for 21days. Estradiol had only limited inhibitory effects on growth in hPASMCs and no effect in hLFs, whereas 2ME exhibited strong and concentration-dependent (1-10microM) antimitogenic effects in both cell types. Bleomycin caused lung injury/PH (significantly increased lung and right ventricle (RV) weights, RV peak systolic pressure (RVPSP), and RV/left ventricle + septum ratio (RV/LV + S); caused medial hypertrophy and adventitial widening of pulmonary arteries; induced marked focal/diffuse fibrosis with diffuse infiltration of inflammatory (ED1+) cells; and resulted in 30% mortality). OVX exacerbated the disease and increased mortality (to 75%); whereas 2ME tended to reduce mortality (55.5%) and in surviving animals reduced RVPSP and RV/LV + S ratio, and attenuated vascular remodeling, pulmonary inflammation and fibrosis. This study suggests that 2ME may have protective effects in bleomycin-induced PH and fibrosis. Further investigation of 2ME in pulmonary fibrosis and PH is warranted.

Preventive effects of raloxifene, a selective estrogen receptor modulator, on monocrotaline-induced pulmonary hypertension in intact and ovariectomized female rats

We investigated whether the chronic treatment with raloxifene, a selective estrogen receptor modulator, prevents the development of monocrotaline-induced pulmonary hypertension in ovary-intact and ovariectomized female rats. Four weeks after a single subcutaneous injection of monocrotaline (60 mg/kg), right ventricular systolic pressure, right ventricle-to-left ventricle plus septal weight ratio, pulmonary arterial medial thickening and endothelin-1 levels in right ventricular tissue increased significantly in both female rats, compared with saline-treated control rats. These monocrotaline-induced alterations were much greater in ovariectomized rats than the changes in intact females. Daily oral administration of raloxifene (10 mg/kg/day for 4 weeks) significantly attenuated the increase in right ventricular systolic pressure to the same levels in both groups of animals, but raloxifene suppressed the increases in right ventricle-to-left ventricle plus septal weight ratio and pulmonary arterial medial thickness more efficiently in ovariectomized females than the case with intact females. In addition, raloxifene completely suppressed the increase in right ventricular endothelin-1 levels in ovariectomized rats, but not in intact females. These data suggest that chronic treatment with raloxifene effectively prevents the development of monocrotaline-induced pulmonary hypertension in ovariectomized female rats than in intact females, at least in part, by suppressing right ventricular endothelin-1 overproduction.

The effects of estrogen on pulmonary artery vasoreactivity and hypoxic pulmonary vasoconstriction: potential new clinical implications for an old hormone

BACKGROUND AND OBJECTIVES

Recent research recognizes gender as a major factor determining the outcomes in trauma, ischemia/reperfusion, shock, and sepsis. In particular, estrogen has been demonstrated to exert protective effects in these settings. The effects of estrogens on the pulmonary vasculature are potent and complex yet not fully understood. A better mechanistic understanding may allow for future therapeutic interventions in pulmonary hypertensive crises after cardiac surgery and during acute lung injury as well as in patients with pulmonary arterial hypertension.

DATA SOURCES AND STUDY SELECTION

We searched PubMed for articles in the English language by using the search words pulmonary hypertension, hypoxic pulmonary vasoconstriction, estrogen, estradiol, inflammation, acute injury, ischemia reperfusion, sepsis, trauma, and burns. These were used in various combinations. We read the abstracts of the relevant titles to confirm their relevance, and the full articles were then extracted. References from extracted articles were checked for any additional relevant articles.

DATA EXTRACTION AND SYNTHESIS

Estrogen plays a critical role in the improved outcomes in the settings of trauma, shock, sepsis, myocardial ischemia/reperfusion, and acute lung injury. Several new mechanisms of action have been identified. In the pulmonary vasculature, estrogen causes vasodilation and attenuates the vasoconstrictor response to various stimuli, including hypoxia. This is mediated by increased levels of prostacyclin and nitric oxide as well as decreased levels of endothelin-1. In addition, effects on intracellular signaling pathways and several kinases as well as anti-inflammatory mechanisms may contribute as well. Recent studies suggest the importance of acute, nongenomic effects.

CONCLUSION

Estrogen exerts a variety of nongenomic actions, which may allow for future therapeutic interventions in pulmonary vascular disease.

Characterization of Hemodynamics in Patients with Idiopathic and Thromboembolic Pulmonary Hypertension

Demographic and hemodynamic data from patients with idiopathic pulmonary arterial hypertension (IPAH) and chronic thromboembolic pulmonary hypertension (CTEPH) have not been systematically characterized to identify differences related to gender, age, race, disease severity, and drug response. Our goal was to define the distribution and relation of IPAH and CTEPH based on these criteria. Hemodynamic and demographic data from 242 IPAH patients and 90 CTEPH patients were collected and compared. IPAH incidence was greater in women, but men had a higher basal mean pulmonary arterial pressure (mPAP). mPAP was comparable among all IPAH ethnic groups. IPAH patients with no history of fenfluramine-phentermine use had a higher mPAP than users. Exercise-induced IPAH was apparent in 14.5% of IPAH patients. Only 9% of IPAH patients responded to inhaled nitric oxide with a ≥20% decrease in mPAP. Compared to CTEPH patients, mPAP was greater but average age of diagnosis was lower in IPAH patients. mPAP negatively correlated with age of diagnosis in IPAH patients only. These results indicate that elevated CO is not the main determinant of mPAP in both IPAH and CTEPH patients. However, the two patient groups differ in terms of their demographic and hemodynamic distributions, and according to the correlation between mPAP and other clinical hemodynamics and demographics.