Autoimmune rheumatic diseases in women

Influence of estradiol treatment on bone marrow cell differentiation in collagenase-induced arthritis

OBJECTIVE AND DESIGN

Estrogen is one of the important regulators of the balance between bone formation and bone resorption that can modulate the levels and activity of certain growth factors and cytokines. In this study, we investigated the effect of 17β-estradiol (ED) on bone marrow (BM) cell differentiation in vivo and ex vivo in a mouse model of collagenase-induced osteoarthritis (CIOA).

SUBJECT

ICR (CD-2) female mice were used in present experiments (total number = 75) and bone marrow cells were used for in vitro studies.

TREATMENT

Mice were orally fed under different schemes with 17β-estradiol at a dose of 2 μg or 4 μg for 30 days.

METHODS

The effect of estradiol was estimated by histopathological, flow cytometry, and ELISA assays. Statistical differences were determined by one-way ANOVA.

RESULTS

Estradiol treatment ameliorated cartilage destruction and osteophyte formation if started from day 0 of CIOA induction, attended with a decrease of uterine and ovarian weights. Long time treatment lowered the percentage of megakaryocyte/platelet (CD62P+) populations and osteoclast (RANK+) populations in BM. Cells obtained from estradiol-treated CIOA mice showed inhibited capacity to differentiate into RANK+ and mesenchymal cells under osteoclastogenic conditions in vitro. Estrogen decreased serum IL-6 levels.

CONCLUSION

Results indicate a potential protective role for estrogen against the development of OA.

Ovarian Hormone-dependent and Spinal ERK Activation-regulated Nociceptive Hypersensitivity in Female Rats with Acid Injection-induced Chronic Widespread Muscle Pain

Symptoms of chronic widespread muscle pain (CWP) meet most of the diagnostic criteria for fibromyalgia syndrome, which is prevalent in females. We used an acid injection-induced muscle pain (AIMP) model to mimic CWP. After female rats received an ovariectomy (OVX), acid saline solution was injected into the left gastrocnemius muscle. Time courses of changes in pain behaviours and p-ERK in the spinal cord were compared between groups. Intrathecal injections of oestradiol (E2) to the OVX group before two acid injections and E2 or progesterone (P4) injections in male rats were compared to evaluate hormone effects. We found that repeated acid injections produced mechanical hypersensitivity and enhanced p-ERK expression in the spinal dorsal horn. OVX rats exhibited significantly less tactile allodynia than did the rats in the other groups. The ERK inhibitor U0126 alleviated mechanical allodynia with lower p-ERK expression in the sham females but did not affect the OVX rats. Intrathecal E2 reversed the attenuated mechanical hypersensitivity in the OVX group, and E2 or P4 induced transient hyperalgesia in male rats. Accordingly, our results suggested that ovarian hormones contribute to AIMP through a spinal p-ERK-mediated pathway. These findings may partially explain the higher prevalence of fibromyalgia in females than males.

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.

The Effect of Male Sex on Survival in Systemic Sclerosis

Objective.

Systemic sclerosis (SSc) has a female predominance, however, little is understood about the effect of sex on SSc manifestations and survival. The objectives of our study were to evaluate differences in disease manifestations, and survival rates between males and females with SSc.

Methods.

A retrospective cohort study of the Toronto Scleroderma Program was conducted to evaluate sex-based differences in disease manifestations and survival. A relative survival analysis compared SSc survival to the general population.

Results.

There were 959 patients (791 females, 168 males) identified, with a female:male ratio of 4.7:1. Males more frequently had diffuse SSc [45% vs 30%, relative risk (RR) 1.44, 95% CI 1.18–1.75] and interstitial lung disease (ILD; 41% vs 33%, RR 1.24, 95% CI 1.01–1.52). There were 324 deaths (65 males, 259 females). Males had increased unadjusted mortality compared to females (HR 1.57, 95% CI 1.19–2.06). In an adjusted model including immunosuppressive use, male sex (HR 1.40, 95% CI 1.06–1.85), ILD (HR 1.58, 95% CI 1.26–1.98), and older age at diagnosis (HR 1.05, 95% CI 1.04–1.06) were independently associated with increased mortality, whereas the limited subtype (HR 0.70, 95% CI 0.49–0.77) and anticentromere antibodies (HR 0.70, 95% CI 0.49–0.98) were independently associated with decreased mortality. Male sex was associated with increased risk of mortality (HR 1.16, p = 0.003) in patients with SSc above that observed for males in the general population.

Conclusion.

The differential effect of disease between sexes is small, yet males have decreased survival compared to females with SSc.

Interferon-gamma induced nitric oxide-mediated apoptosis of anemia of chronic disease in rheumatoid arthritis

Proinflammatory cytokines play a role in the pathogenesis of anemia of chronic disease (ACD), which is a common cause of anemia in rheumatoid arthritis (RA). Anemia in RA is associated with increased apoptosis of erythroid cells. However, there is unclear information on the mechanism of ACD in the disease. The purpose of this study is to investigate the role of cytokines on nitric oxide-mediated apoptosis in erythroid progenitor cells of ACD in RA patients. Erythroid progenitor cells from healthy subjects and RA patients with ACD were treated with cytokines like interleukin-1β, tumor necrosis factor-α, and interferon-γ at concentrations of 2, 20, and 40 ng/ml for 14 days. Cell viability and cell apoptosis were analyzed by trypan blue staining and flow cytometry, respectively. The results showed that the highest effect of cytokines on reduction cell viability and induction cell apoptosis was found in 20 ng/ml IFN-γ-treated cells of RA patients. In addition, IFN-γ showed significantly increased nitric oxide production and iNOS mRNA expression, which was measured by Griess assay and real-time PCR, respectively. The percentage of cell apoptosis and NO production was reduced after an inducible nitric oxide synthase inhibitor, SMT, treatment. In conclusion, IFN-γ could induce nitric oxide production-mediated apoptosis process, which might be involved in the pathogenesis of ACD in RA patients.

Gender aspects in skin diseases

Gender differences in medicine have been recognized in anatomy, physiology, as well as in epidemiology and manifestations of various diseases. With respect to skin disorders, males are generally more commonly afflicted with infectious diseases while women are more susceptible to psychosomatic problems, pigmentary disorders, certain hair diseases, and particularly autoimmune as well as allergic diseases. Significantly, more female sex-associated dermatoses can be identified than the male sex-associated dermatoses. Dermatoses in the genital area differ between men and women. Gender differences also exist in the occurrence and prognosis of certain skin malignancies. The mechanisms underlying gender differences in skin diseases remain largely unknown. Differences in the skin structure and physiology, effect of sex hormones, ethnic background, sociocultural behaviour and environmental factors may interact to exert the influences. A better understanding of gender differences in human health and diseases will allow the development of novel concepts for prevention, diagnosis and therapy of skin diseases.

Comparison of work disability and health-related quality of life between males and females with rheumatoid arthritis below the age of 45 years

OBJECTIVES

To compare work disability (WD) and health status between males and females with rheumatoid arthritis (RA) in the age group 18-45 years, and to compare health status between patients with and without WD within each gender, and finally to identify factors independently associated with WD in this age group.

METHODS

A cross-sectional study of RA patients at the time starting with disease-modifying antirheumatic drug (DMARD) therapy and/or biological treatment. Patients receiving a permanent, national WD pension corresponding to >or= 50% were defined as work disabled. We examined gender differences with regard to disease characteristics, health status and WD. The Mann-Whitney U-test and Pearson's chi(2)-test were applied for group comparisons. Multiple logistic regression analyses with adjustments for duration of education, disease duration, age, erosive disease, disability score [using the Modified Health Assessment Questionnaire (MHAQ)], Disease Activity Score-28 (DAS-28), the Short Form Health Survey (SF-36) mental health score and gender were used to identify variables associated with WD.

RESULTS

Out of 474 (372 females) patients, the number (%) of work-disabled females/males was 91 (24.7)/8 (8.1) (p<0.001). WD was associated with worse health status in both genders. The odds ratio (95% confidence interval) [OR (95% CI)] for WD in females vs. males was 4.84 (1.85-12.65) in the multivariate analyses. Other factors independently associated with WD were worse mental health, disease duration and low level of education.

CONCLUSION

Females with RA had a fourfold increased risk of WD compared to men. Low level of education, disease duration and worse mental health were also independently associated with WD.

The role of female gonadal hormones in behavioral sex differences in persistent and chronic pain: Clinical versus preclinical studies

Clinical and preclinical studies have found sex-specific differences in the discrimination and perception of nociceptive stimuli. This article reviews the current literature concerning the biological basis of sex differences in the behavioral response to persistent inflammatory and chronic pain stimuli. The emerging picture from both clinical and preclinical studies suggests that the basis of these differences in nociceptive responses to such stimuli resides in the regulatory activity of gonadal hormones in the central nervous system. Published reports suggest that pain management targeted at female patients should consider hormonal factors during the female reproductive cycle.

Aromatase-deficient mice spontaneously develop a lymphoproliferative autoimmune disease resembling Sjogren's syndrome

Sjögren's syndrome (SS) is an incurable, autoimmune exocrinopathy that predominantly affects females and whose pathogenesis remains unknown. Like rheumatoid arthritis, its severity increases after menopause, and estrogen deficiency has been implicated. We have reported that estrogen receptor-alpha and -beta-knockout mice develop autoimmune nephritis and myeloid leukemia, respectively, but neither develops SS. One model of estrogen deficiency in rodents is the aromatase-knockout (ArKO) mouse. In these animals, there is elevated B lymphopoiesis in bone marrow. We now report that ArKO mice develop severe autoimmune exocrinopathy resembling SS. By 1 year of age, there is B cell hyperplasia in the bone marrow, spleen, and blood of ArKO mice and spontaneous autoimmune manifestations such as proteinuria and severe leukocyte infiltration in the salivary glands and kidney. Also, as is typically found in human SS, there were proteolytic fragments of alpha-fodrin in the salivary glands and anti-alpha-fodrin antibodies in the serum of both female and male ArKO mice. When mice were raised on a phytoestrogen-free diet, there was a mild but significant incidence of infiltration of B lymphocytes in WT mice and severe destructive autoimmune lesions in ArKO mice. In age-matched WT mice fed a diet containing normal levels of phytoestrogen, there were no autoimmune lesions. These results reveal that estrogen deficiency results in a lymphoproliferative autoimmune disease resembling SS and suggest that estrogen might have clinical value in the prevention or treatment of this disease.

Prevalence and outcomes of anemia in rheumatoid arthritis: a systematic review of the literature

Anemia is a common comorbidity in individuals with rheumatoid arthritis (RA). In fact, anemia of the type characterized by low serum iron concentrations in conjunction with adequate iron stores is frequently associated with RA and has served as a model for anemia of chronic disease. A systematic search of the scientific literature published since January 1966 identified 19 articles that reported findings on either the prevalence of anemia in patients with RA or outcomes for patients with anemia and RA. Ten articles addressed the prevalence of anemia in patients with RA. Estimates of the prevalence of mild anemia ranged between 33% and 60%; however, the 2 studies that examined demographics in patients with RA did not identify subpopulations at particular risk for anemia. Twelve articles assessed the impact of the resolution of anemia on symptoms and quality of life (QOL) in patients with RA. For many of the parameters assessed-including swollen, painful, and tender joints, pain, muscle strength, and energy levels-a positive correlation was observed between improvement of symptoms and the resolution of anemia. In addition, 2 studies reported a significant improvement in QOL scores in patients with RA who experienced a response to treatment for anemia. These results suggest that (1) patients with RA who have anemia are likely to have more severe joint disease and (2) if the anemia is successfully treated, the joint disease will likely respond to treatment as well. Whether improvements in QOL and/or joint symptoms occur with improvement of anemia, independent of other signs of an overall response to RA therapy, remains to be determined.

Estradiol Treatment Redirects the Isotype of the Autoantibody Response and Prevents the Development of Autoimmune Arthritis

A number of clinical and experimental observations have been made relating elevated estrogen levels with the amelioration of autoimmune diseases, yet questions remain about the levels required for efficacy as well as the mechanism of disease inhibition. Using the collagen-induced arthritis (CIA) model, we have studied the effects of physiological, sustained levels of 17beta-estradiol in preventing the development of autoimmune arthritis and analyzed the changes in the autoimmune response. Using time-release pellets of 17beta-estradiol, arthritis development was significantly inhibited in three different strains of CIA-susceptible mice compared with the effect of placebo treatment, and serum estradiol levels similar to those of mice in estrus were found to be equally effective as higher estradiol concentrations. Analysis of the autoimmune response in the estradiol-treated mice indicated that T cell production of IFN-gamma was markedly decreased, and significant decreases were also observed in levels of IL-10 and GM-CSF produced by lymph nodes cells from estradiol-treated mice. Although the total IgG anti-CII response was only minimally affected by estrogen treatment, a significant reduction in the levels of IgG2a anti-CII Abs and an increase in the levels of IgG1 anti-CII Abs were observed in estradiol-treated mice. These data indicate that estradiol treatment altered the Th profile of the autoimmune T cell response, which, in turn, altered the production of IgG Abs to an isotype that is poor at fixing complement, an important component in the immunopathogenesis of CIA.