Are both genetic and reproductive associations with rheumatoid arthritis linked to prolactin?

Dual Roles of Prolactin and Vasoinhibin in Inflammatory Arthritis

The term inflammatory arthritis defines a family of diseases, including rheumatoid arthritis (RA), caused by an overactive immune system, and influenced by host aspects including sex, reproductive state, and stress. Prolactin (PRL) is a sexually dimorphic, reproductive, stress-related hormone long-linked to RA under the general assumption that it aggravates the disease. However, this conclusion remains controversial since PRL has both negative and positive outcomes in RA that may depend on the hormone circulating levels, synthesis by joint tissues, and complex interactions at the inflammatory milieu. The inflamed joint is rich in matrix metalloproteases that cleave PRL to vasoinhibin, a PRL fragment with proinflammatory effects and the ability to inhibit the hyperpermeability and growth of blood vessels. This review addresses this field with the idea that explanatory mechanisms lie within the PRL/vasoinhibin axis, an integrative framework influencing not only the levels of systemic and local PRL, but also the proteolytic conversion of PRL to vasoinhibin, as vasoinhibin itself has dual actions on joint inflammation. In this review, we discuss recent findings from mouse models suggesting the upregulation of endogenous vasoinhibin by the pro-inflammatory environment and showing dichotomous actions and signaling mechanisms of PRL and vasoinhibin on joint inflammation that are cell-specific and context-dependent. We hypothesize that these opposing actions work together to balance the inflammatory response and provide new insights for understanding the pathophysiology of RA and the development of new treatments.

Primary biliary cirrhosis associated with myasthenia gravis after postpartum: a case report

Background

Autoimmune diseases refers to a class of diseases involving abnormal immune response of human body and tissue damage caused by the dysregulation of autoimmune balance or destruction of immune tolerance. Recent research has revealed that the occurrence of autoimmune diseases is influenced by genetic, hormonal, immunological, and environmental factors. As sex hormone levels change obviously during pregnancy and postpartum, the morbidity and recurrence rate of autoimmune diseases increase during this period.

Case presentation

A 31-year-old Asian woman was admitted to our hospital for myasthenia gravis and treated with methylprednisolone and pyridostigmine bromide 3 months postpartum. Physical examination and laboratory inspection after admission suggested that the patient had primary biliary cirrhosis. Subsequently, azathioprine was added to the treatment, and the symptoms of both diseases were successfully controlled.

Conclusions

This case exhibits a rare condition of myasthenia gravis combined with primary biliary cirrhosis postpartum. Given the fluctuation of the immune status during the postpartum period, combined autoimmune diseases need to be taken into account when patients develop clinical symptoms of an autoimmune disease. Therefore, detailed physical and laboratory examination can help to prevent the missed diagnosis of these diseases.

Vasoinhibin reduces joint inflammation, bone loss, and the angiogenesis and vasopermeability of the pannus in murine antigen-induced arthritis

Increased permeability and growth (angiogenesis) of blood vessels play a key role in joint swelling and pannus formation in inflammatory arthritis, a family of diseases influenced by reproductive hormones. The hormone prolactin (PRL) protects against joint inflammation, pannus formation, and bone destruction in adjuvant-induced arthritis and these effects may involve its proteolytic conversion to vasoinhibin, a PRL fragment that inhibits angiogenesis and vasopermeability. Here, we show that the intra-articular injection of an adeno-associated virus type-2 (AAV2) vector encoding vasoinhibin reduced joint inflammation, the hyperplasia, vascular density, and vasopermeability of the pannus, and the loss of bone in mice subjected to antigen-induced arthritis. In agreement, the AAV2 vasoinhibin vector reduced the expression of proinflammatory cytokines (interleukin-1β, interleukin-6), an endothelial cell marker (platelet endothelial cell-adhesion molecule 1), and proangiogenic molecules [vascular endothelial growth factor (VEGF), VEGF receptor 2, and hypoxia-inducible factor 1α] in the arthritic joint. Also, vasoinhibin reduced the synovial vasopermeability induced by the intra-articular injection of VEGF in healthy mice. Finally, vasoinhibin signals by blocking the phosphorylation/activation of endothelial nitric oxide synthase (eNOS) at Ser1179 and the AAV2 vasoinhibin vector inhibited the enhanced phosphorylation of eNOS Ser1179 in the arthritic joint. We conclude that vasoinhibin reduces joint inflammation and bone loss in arthritis by inhibiting pannus angiogenesis and vasopermeability via the blockage of VEGF-induced eNOS activation. These findings suggest the potential therapeutic benefit of AAV2-mediated vasoinhibin gene delivery in arthritis.

Exacerbations of autoimmune diseases during pregnancy and postpartum

Autoimmune diseases represent a complex heterogeneous group of disorders that occur as a results of immune homeostasis dysregulation and loss of self-tolerance. Interestingly, more than 80% of the cases are found among women at reproductive age. Normal pregnancy is associated with remarkable changes in the immune and endocrine signaling required to tolerate and support the development and survival of the placenta and the semi-allogenic fetus in the hostile maternal immune system environment. Gravidity and postpartum represent an extremely challenge period, and likewise the general population, women suffering from autoimmune disorders attempt pregnancy. Effective preconception counseling and subsequent gestation and postpartum follow-up are crucial for improving mother and child outcomes. This comprehensive review provides information about the different pathways modulating autoimmune diseases activity and severity, such as the influence hormones, microbiome, infections, vaccines, among others, as well as updated recommendations were needed, in order to offer those women better medical care and life quality.

CCL5 and related genes might be the potential diagnostic biomarkers for the therapeutic strategies of rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is a common disease of rheumatic diseases. The aim of this study was to identify gene signatures in RA and uncover their potential mechanisms.

METHOD

Gene expression profiles of GSE1919, GSE55235, GSE55457, and GSE77928 were downloaded from GEO database. The above four series contained 76 samples, including 44 RA patients and 32 normal controls. The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed, and protein-protein interaction (PPI) network of the differentially expressed genes (DEGs) was constructed by Cytoscape software.

RESULTS

Up-regulated DEGs were significantly enriched in biological processes, including immune response, positive regulation of immune system process and regulation of immune system process, while down-regulated DEGs were significantly enriched in biological processes, including response to oxygen-containing compound, cellular lipid metabolic process, and lipid metabolic process. KEGG pathway analysis showed the up-regulated DEGs were enriched in cytokine-cytokine receptor interaction, chemokine signaling pathway, and primary immunodeficiency. The 104 hub genes, which were significantly differently expressed between patients and normal controls in at least two datasets, were identified from the PPI network, and subnetworks revealed that these genes were involved in significant pathways, including cytokine-cytokine receptor interaction, chemokine signaling pathway, and primary immunodeficiency.

CONCLUSION

The present study indicated that the identified DEGs and hub genes promote our understanding of molecular mechanisms underlying the development of RA, such as C-C motif chemokine 5 (CCL5), might have a negative impact in the development of RA. CCL5 and its related genes might be the potential diagnostic biomarkers for the therapeutic strategies of RA.

Replication of Associations of Genetic Loci Outside the HLA Region With Susceptibility to Anti-Cyclic Citrullinated Peptide-Negative Rheumatoid Arthritis

Objective

Genetic polymorphisms within the HLA region explain only a modest proportion of anti–cyclic citrullinated peptide (anti‐CCP)–negative rheumatoid arthritis (RA) heritability. However, few non‐HLA markers have been identified so far. This study was undertaken to replicate the associations of anti‐CCP–negative RA with non‐HLA genetic polymorphisms demonstrated in a previous study.

Methods

The Rheumatoid Arthritis Consortium International densely genotyped 186 autoimmune‐related regions in3,339 anti‐CCP–negative RA patients and 15,870 controls across 6 different populations using the Illumina ImmunoChip array. We performed a case–control replication study of the anti‐CCP–negative markers with the strongest associations in that discovery study, in an independent cohort of anti‐CCP–negative UK RA patients. Individuals from the arcOGENConsortium and Wellcome Trust Case Control Consortium were used as controls. Genotyping in cases was performed using Sequenom MassArray technology. Genome‐wide data from controls were imputed using the 1000 Genomes Phase I integrated variant call set release version 3 as a reference panel.

Results

After genotyping and imputation quality control procedures, data were available for 15 non‐HLA single‐nucleotide polymorphisms in 1,024 cases and 6,348 controls. We confirmed the known markers ANKRD55 (meta‐analysis odds ratio [OR] 0.80; P = 2.8 × 10⁻¹³)and BLK (OR 1.13; P = 7.0 × 10⁻⁶) and identified new and specific markers of anti‐CCP–negative RA (prolactin [PRL] [OR 1.13; P = 2.1 × 10⁻⁶] and NFIA [OR 0.85; P = 2.5 × 10⁻⁶]). Neither of these loci is associated with other common, complex autoimmune diseases.

Conclusion

Anti‐CCP–negative RA and anti‐CCP–positive RA are genetically different disease subsets that only partially share susceptibility factors. Genetic polymorphisms located near the PRL and NFIA genes represent examples of genetic susceptibility factors specific for anti‐CCP–negative RA.

Prolactin blocks the expression of receptor activator of nuclear factor κB ligand and reduces osteoclastogenesis and bone loss in murine inflammatory arthritis

Background

Prolactin (PRL) reduces joint inflammation, pannus formation, and bone destruction in rats with polyarticular adjuvant-induced arthritis (AIA). Here, we investigate the mechanism of PRL protection against bone loss in AIA and in monoarticular AIA (MAIA).

Methods

Joint inflammation, trabecular bone loss, and osteoclastogenesis were evaluated in rats with AIA treated with PRL (via osmotic minipumps) and in mice with MAIA that were null (Prlr-/-) or not (Prlr+/+) for the PRL receptor. To help define target cells, synovial fibroblasts from Prlr+/+ mice were treated or not with proinflammatory cytokines ((Cyt), including TNFα, IL-1β, and interferon (IFN)γ) with or without PRL, and these synovial cells were co-cultured or not with bone marrow osteoclast progenitors from Prlr+/+ or Prlr-/- mice.

Results

In AIA, PRL treatment reduced joint swelling, increased trabecular bone area, lowered osteoclast density, and reduced mRNA levels of osteoclast-associated genes (tartrate-resistant acid phosphatase (Trap)), cathepsin K (Ctsk), matrix metalloproteinase 9 (Mmp9), and receptor activator of nuclear factor κB or RANK (Tnfrsf11a)), of genes encoding cytokines with osteoclastogenic activity (Tnfa, Il1b, Il6, and receptor activator of nuclear factor κB ligand or RANKL (Tnfrsf11)), and of genes encoding for transcription factors and cytokines related to T helper (Th)17 cells (Rora, Rorc, Il17a, Il21, Il22) and to regulatory T cells (Foxp3, Ebi3, Il12a, Tgfb1, Il10). Prlr-/- mice with MAIA showed enhanced joint swelling, reduced trabecular bone area, increased osteoclast density, and elevated expression of Tnfa, Il1b, Il6, Trap, Tnfrsf11a, Tnfrsf11, Il17a, Il21, Il22, 1 l23, Foxp3, and Il10. The expression of the long PRL receptor form increased in arthritic joints, and in synovial membranes and cultured synovial fibroblasts treated with Cyt. PRL induced the phosphorylation/activation of signal transducer and activator of transcription-3 (STAT3) and inhibited the Cyt-induced expression of Il1b, Il6, and Tnfrsf11 in synovial fibroblast cultures. The STAT3 inhibitor S31-201 blocked inhibition of Tnfrsf11 by PRL. Finally, PRL acted on both synovial fibroblasts and osteoclast precursor cells to downregulate Cyt-induced osteoclast differentiation.

Conclusion

PRL protects against osteoclastogenesis and bone loss in inflammatory arthritis by inhibiting cytokine-induced expression of RANKL in joints and synovial fibroblasts via its canonical STAT3 signaling pathway.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1290-4) contains supplementary material, which is available to authorized users.

Increased risk for clinical onset of myasthenia gravis during the postpartum period

OBJECTIVE

To study the risk of clinical onset of myasthenia gravis (MG) in pregnancy and during the first 6 months postpartum because an association between pregnancy or the postpartum period and the onset of autoimmune MG is widely assumed but not proven.

METHODS

The design was a cross-sectional population-based cohort study of 2 MG cohorts (Norway and the Netherlands) with 1,038 healthy controls from Norway. Data were obtained on 246 women with MG (age at onset 15-45 years). Data on pregnancy, hormonal factors, and clinical symptoms were collected by a previously validated environmental MG questionnaire. Relative risk of MG onset before, during, and after pregnancy was calculated by multinomial logistic regression for Norwegian women reaching 45 years of age, adjusted for the observed distribution of person-years in the corresponding control group.

RESULTS

Of the included women with MG, 13 (11.5%) of the Dutch and 24 (18.0%) of the Norwegian patients had their first myasthenia symptoms during the pregnancy or postpartum period. The postpartum period was confirmed to be significantly associated with the onset of symptoms of MG in Norwegian women with MG (relative risk 5.5, 95% confidence interval 2.6-11.6). The risk was highest after the first childbirth.

CONCLUSIONS

Women have a high-risk period for the onset of clinical symptoms of MG in the postpartum period, in particular after the first childbirth. Future studies should aim at elucidating the role of the hormonal-immunological-genetic interaction in the pathogenesis of MG.

The role of the prolactin/vasoinhibin axis in rheumatoid arthritis: an integrative overview

Rheumatoid arthritis (RA) is a chronic, autoimmune, inflammatory disease destroying articular cartilage and bone. The female preponderance and the influence of reproductive states in RA have long linked this disease to sexually dimorphic, reproductive hormones such as prolactin (PRL). PRL has immune-enhancing properties and increases in the circulation of some patients with RA. However, PRL also suppresses the immune system, stimulates the formation and survival of joint tissues, acquires antiangiogenic properties upon its cleavage to vasoinhibins, and protects against joint destruction and inflammation in the adjuvant-induced model of RA. This review addresses risk factors for RA linked to PRL, the effects of PRL and vasoinhibins on joint tissues, blood vessels, and immune cells, and the clinical and experimental data associating PRL with RA. This information provides important insights into the pathophysiology of RA and highlights protective actions of the PRL/vasoinhibin axis that could lead to therapeutic benefits.

Breastfeeding practice, oral contraceptive use and risk of rheumatoid arthritis among Chinese women: the Guangzhou Biobank Cohort Study

OBJECTIVE

Hormonal and reproductive factors are implicated in the aetiology of RA, but results of previous studies have been mixed. The aim of this cross-sectional study was to assess the relationships between RA, use of oral contraceptives (OCs) and history of breastfeeding in a population of older women from South China.

METHODS

We used baseline data from 7349 women ≥ 50 years of age in the Guangzhou Biobank Cohort. Questionnaires were used to obtain socio-demographic, lifestyle and obstetric history data, including parity, OC use and breastfeeding practices. The main outcome was RA. Women were asked about history of RA and were examined to assess joint swelling. RF levels were measured. The presence of RA was defined in two ways: (i) as reporting physician-diagnosed RA or pain and swelling in at least three joints (including the wrist), and (ii) also having at least one of the following: positive RF, morning stiffness or objective swelling of the small joints of the hands.

RESULTS

Compared with those who had never breastfed, breastfeeding was associated with half the risk of RA. The risk was lower with increasing duration of breastfeeding [adjusted odds ratio (OR) 0.54 (95% CI 0.29, 1.01) for breastfeeding at least 36 months; P for trend = 0.04]. OC use had no relationship with RA.

CONCLUSION

Breastfeeding (especially longer duration) but not OC use is associated with a lower risk of RA. This has potentially important implications for future RA disease burden, given the declining rates of breastfeeding and the one-child policy in China. Further research is needed to explain the biological mechanism.

Early menopause and severity of rheumatoid arthritis in women older than 45 years

Introduction

We aimed to investigate whether recognized hormonal predictors of rheumatoid arthritis (RA) also influence the severity of RA.

Methods

One hundred thirty-four incident RA cases identified by four different local and national registers, who had participated in a community-based health survey between 1991 and 1996, were included. By a retrospective structured review of the medical records, information on the use of disease-modifying antirheumatic drugs (DMARDs), erosions on radiographs, rheumatoid factor (RF) status, and disability measured by using the health assessment questionnaire (HAQ) were collected. The variables were added to the SPSS TwoStep Cluster Analysis to reveal natural groupings of RA severity. Known hormonal predictors analyzed were breastfeeding history, history of oral contraceptive (OC) use, and menopausal age.

Results

The mean age at RA diagnosis was 63.4 years; 72% were RF positive, and 28% had received biological treatment. Three clusters were identified, one with severe RA, one with mild/moderate RF-positive RA, and one with mild/moderate RF-negative RA. A significant difference (P = 0.005) was found in the distribution of clusters between patients with a history of early menopause compared with those with menopause after 45 years, with a higher proportion with mild/moderate RF-negative RA in the early-menopause subset. No major difference in severity of the disease was noted depending on OC use or history of breastfeeding.

Conclusions

Early menopause was associated with a milder form of RA. Hormonal changes may influence pathways that are distinct from those leading to severe, progressive disease.

Precipitating and perpetuating factors of rheumatoid arthritis immunopathology: linking the triad of genetic predisposition, environmental risk factors and autoimmunity to disease pathogenesis

Rheumatoid arthritis (RA) is considered to occur when genetic and environmental factors interact to trigger immunopathological changes and consequently an inflammatory arthritis. Over the last few decades, epidemiological and genetic studies have identified a large number of risk factors for RA development, the most prominent of which comprise cigarette smoking and the shared epitope alleles. These risks appear to differ substantially between anti-cyclic citrullinated peptide (ACPA)-positive and ACPA-negative disease. In this article, we will summarise the risk factors for RA development that have currently been identified, outlining the specific gene-environment and gene-gene interactions that may occur to precipitate and perpetuate autoimmunity and RA. We will also focus on how this knowledge of risk factors for RA may be implemented in the future to identify individuals at a high risk of disease development in whom preventative strategies may be undertaken.

Why are women predisposed to autoimmune rheumatic diseases?

The majority of autoimmune diseases predominate in females. In searching for an explanation for this female excess, most attention has focused on hormonal changes - both exogenous changes (for example, oral contraceptive pill) and fluctuations in endogenous hormone levels particularly related to menstruation and pregnancy history. Other reasons include genetic differences, both direct (influence of genes on sex chromosomes) and indirect (such as microchimerism), as well as gender differences in lifestyle factors. These will all be reviewed, focusing on the major autoimmune connective tissue disorders: rheumatoid arthritis, systemic lupus erythematosus and scleroderma.

Trends in Respiratory Morbidity of Children in Relation to their Passive Smoking Exposure

AIMS

Exposure of children to passive smoking is significantly associated with respiratory morbidity. Youngest children between 0-2 years are harmed in the most significant way, while, together with the growing age a decrease is observed of prevalence of respiratory diseases and influence of passive smoking.

METHODS

During repeated investigations of children from European Longitudinal Study of Pregnancy and Childhood (ELSPAC) it was assessed, whether and how in the period from the birth to five years of age varied the rate of children exposed to environment filled with smoke and what were the differences in the frequency of diseases among the groups of children with different exposure level. Some selected characteristics of health were chosen from documentation provided in the 6th, 18th month and 5 years of children's age and processed in four children groups that differ in smoking behaviour of their mothers. The differences were statistically assessed in SPSS programme.

RESULTS

In all compared age categories were children of smoking mothers more often exposed to stay in environment filled with smoke: children of middle and heavy smokers more, children of light smokers less. In all groups of smoking mothers, children were more often protected from exposure to passive smoking in the age of six months than after they reached 18 months and 5 years of age: differences were mostly statistically significant on the level of 1% of significance. Attending the kindergarten presents significant protecting factor for five years old children: they are more exposed during weekends than on week days (p < 0.001, resp. p < 0.01). Both respiratory symptomatology and morbidity were highly significantly increased in previous life periods of those children, whose mothers smoked. At the age of five, life in smoking household causes more frequent incidence of asthmatic symptomatology: wheezing and apnoe, and higher prevalence of allergies against home and pollen dust with breathlessness and wheezing as well (p < 0.05).

CONCLUSIONS

ELSPAC study ascertained significant influence of maternal smoking on children's health in relation to passive smoking. Consequences of exposure clinically manifest themselves especially in increased incidence of respiratory and allergic morbidity.

Do breast-feeding and other reproductive factors influence future risk of rheumatoid arthritis?: Results from the Nurses' Health Study

OBJECTIVE

To explore the contribution of female hormonal factors occurring prior to the onset of rheumatoid arthritis (RA), such as age at menarche, parity, age at first birth, breast-feeding, use of oral contraceptives (OCs), irregular menstrual cycles, and postmenopausal hormone (PMH) use, to the subsequent development of RA in a large female cohort.

METHODS

We studied female reproductive and hormonal risk factors for RA in a cohort of 121,700 women enrolled in the longitudinal Nurses' Health Study. The diagnosis of incident RA (between 1976 and 2002) in 674 women was confirmed by a connective tissue disease screening questionnaire and blinded medical record review for American College of Rheumatology criteria. Sixty percent of the patients with RA were rheumatoid factor positive. The relationship between potential risk factors, including age, age at menarche, parity, age at first birth, total lifetime history of breast-feeding, use of OCs, and irregular menstrual cycles and the multivariate-adjusted risk of RA was estimated using Cox proportional hazards models.

RESULTS

Using a multivariate model that adjusted for age, body mass index, smoking, parity, and other hormonal factors, we observed a strong trend for decreasing risk of RA with increasing duration of breast-feeding (P for trend = 0.001). For women who breast-fed (compared with parous women who did not breast-feed), the risk ratios (RRs) and 95% confidence intervals (95% CIs) were as follows: breast-feeding for < or =3 total months, RR 1.0 (95% confidence interval [95% CI] 0.8-1.2); for 4-11 total months, RR 0.9 (95% CI 0.7-1.1); for 12-23 total months, RR 0.8 (95% CI 0.6-1.0); and for > or =24 total months, RR 0.5 (95% CI 0.3-0.8). Very irregular menstrual cycles were associated with an increased risk of RA (RR 1.4, 95% CI 1.0-2.0). Age at menarche < or =10 years was associated with an increased risk of seropositive RA (RR 1.6, 95% CI 1.1-2.4) but not significantly associated with risk of RA. Parity, total number of children, age at first birth, and OC use were not associated with an increased risk of RA in this cohort.

CONCLUSION

In this large cohort, breast-feeding for >12 months was inversely related to the development of RA. This apparent effect was dose-dependent, with a significant trend toward lower risk with longer duration of breast-feeding. Irregular menstrual cycles and earlier age at menarche increased the risk of RA. Other reproductive hormonal factors were not associated with RA risk.

Smoking, gender and rheumatoid arthritis–epidemiological clues to etiology

OBJECTIVES

This study was undertaken to confirm and extend our earlier observation that gender is a biological effect modifier of smoking-rheumatoid arthritis (RA) relationship in a diverse national survey sample in the United States.

METHODS

Smoking history of 644 cases of RA and 1509 geographically matched general population controls were compared using weighted logistic regression.

RESULTS

There were 644 respondents with RA (cases) and 1509 geographically matched controls. Cases were significantly younger, less educated, more likely to be single and female than controls. Among cases 57% were smokers while among controls 49% smoked. Among women, after adjusting for age, hysterectomy had an age adjusted odds ratio 1.45, (95% CI 0.99-2.10) and menopause an adjusted odds ratio 1.18 (95% CI 0.99-2.10) were associated with smoking. In univariable analysis ever-smoking was associated with increased risk of RA (odds ratio 1.34, 95% CI 1.0-1.81). Among the strata of smokers, there was an increasing gradient of risk with increasing exposure to smoking (P = 0.041). In separate multivariable models, smoking increased the risk in men (odds ratio 2.29, 95% CI 1.35-3.90) while in women the risk was not elevated (odds ratio 0.98, 95% CI 0.67-1.42). After adjusting for the statistically significant interaction both female gender (odds ratio 2.30, 95% CI 1.39-3.83) and having ever smoked (odds ratio 2.31, 95% CI 1.36-3.94) emerged as significant risk factors for RA.

CONCLUSIONS

Gender interacts with smoking in by an unknown mechanism to lead to differential risk of RA.

Estrogen and other female reproductive risk factors are not strongly associated with the development of rheumatoid arthritis in elderly women

OBJECTIVE

Endogenous and exogenous reproductive hormones have been associated with rheumatoid arthritis (RA) in women, but data are inconsistent and no studies have assessed RA risk factors exclusively in elderly women.

METHODS

The authors examined the association between reproductive factors, exogenous hormone exposure, and RA in a prospective cohort study of 31,336 Iowa women who were aged 55 to 69 years at cohort baseline in 1986.

RESULTS

During 11 years of follow-up, 158 incident cases of RA were identified and validated. Age at last pregnancy (P trend =.01) and age at menopause (P trend =.03) were inversely associated with RA, whereas a history of polycystic ovary syndrome (relative risk [RR], 2.58; 95% confidence interval [CI], 1.06 to 6.30), endometriosis (RR, 1.72; 95% CI, 0.93 to 3.18), and former use of hormone replacement therapy (RR, 1.47; 95% CI, 1.04 to 2.06) were positively associated with RA. In multivariate analysis models, a history of polycystic ovary syndrome remained the most consistent predictor of RA, whereas the RRs for other factors attenuated.

CONCLUSION

Few reproductive factors showed a strong or statistically significant association with RA in elderly women. The association of polycystic ovary syndrome may be indicative of perturbations of endocrine-immune activity that may influence the development of RA. This prospective cohort study adds to the understanding of the potential contribution of hormonal factors to the cause of RA in older women.

Comorbidity and lifestyle, reproductive factors, and environmental exposures associated with rheumatoid arthritis

OBJECTIVE

To evaluate the influence of lifestyle, reproduction, and some external factors on the development of rheumatoid arthritis (RA) and to describe its comorbidity.

METHODS

Cases were identified retrospectively from 1980 to 1995 at the University Hospital in Linköping, Sweden. The study comprised 422 cases and 859 randomly selected population referents. Data on possible aetiological factors and comorbidity were collected by postal questionnaire.

RESULTS

The response rates were 67% among cases and 59% among referents. A decrease in the occurrence of atopic allergy was seen in the cases (odds ratio (OR) 0.6, 95% confidence interval (CI) 0.4 to 1.0). There was a positive association between RA and insulin treatment (OR 10.2, 95% CI 1.7 to 60.8) in women, and women with a short fertile period had an increased risk of RA (OR 2.5, 95% CI 1.1 to 5.4). Current and previous smoking were associated with increased risks for RA in both sexes, and in men a dose-response relationship was found with number of tobacco pack years (p for trend <0.005). The risk for RA decreased with increasing level of education in both men and women. Increased risks were seen in men born into households with private wells (OR 2.8, 95% CI 1.5 to 5.2), residentially exposed to mould (OR 4.6, 95% CI 1.1 to 20.2), or exposed to farm animals (OR 3.3, 95% CI 0.7 to 16.6). In women there were positive associations between RA and reporting a previous joint injury (OR 2.5, 95% CI 1.0 to 6.6) and prolonged exposure to hair dyes (OR 1.9, 95% CI 0.8 to 4.5).

CONCLUSIONS

RA, a disease with features of T helper 1 (Th1) dominated immune response, was inversely associated with atopic allergy, a Th2 dominated condition, while there were indications of a strong positive association with Th1 related diabetes mellitus. The results support a causal relationship between smoking and RA. The level of education was inversely associated with RA, while there was a positive association between RA and certain residential factors in men and a short fertile period in women.

Breastfeeding-related onset, flare, and relapse of rheumatoid arthritis

The beneficial effects of pregnancy on rheumatoid arthritis have been known for decades. Only recently, however, have lactation and prolactin been targeted as predictors of onset, flare, or relapse of arthritis. Among genetically susceptible women, breastfeeding is associated with an increased risk of rheumatoid arthritis, particularly after the first pregnancy. Dietary interventions may reduce symptoms experienced by arthritic women.

Molecular dissection of the tissue transglutaminase autoantibody response in celiac disease

Celiac disease (CD) is an intestinal malabsorption characterized by intolerance to cereal proteins accompanied by immunological responses to dietary gliadins and tissue transglutaminase, an autoantigen located in the endomysium. Tissue transglutaminase belongs to the family of enzymes that catalyze protein cross-linking reactions and is constitutively expressed in many tissues as well as being activated during apoptosis. The role of gliadins in eliciting the immune response in CD and how transglutaminase is linked to the primary reaction are still unclear. In this work, we report the production and analysis of six phage Ab libraries from the peripheral and intestinal lymphocytes of three CD patients. We were able to isolate Abs to transglutaminase from all intestinal lymphocytes libraries but not from those obtained from peripheral lymphocytes. This is in contrast to Abs against gliadin, which could be obtained from all libraries, indicating that the humoral response against transglutaminase occurs at the local level, whereas that against gliadin occurs both peripherally and centrally. Abs from all three patients recognized the same transglutaminase epitopes with a bias toward the use of the V(H)5 Ab variable region family. The possible role of these anti-transglutaminase Abs in the onset of CD and associated autoimmune pathologies is discussed.

Roles of prolactin and gonadotropin-releasing hormone in rheumatic diseases

PRL is capable of influencing immune responses and is a cytokine in all likelihood. Circulating PRL is elevated in a number of autoimmune diseases, and about 20% of SLE patients are hyperprolactinemic. The serum PRL concentration often does not reflect disease activity in SLE. The PRL-suppressing drug bromocriptine has been reported to benefit small numbers of patients with reactive arthritis and inflammatory eye disease, and bromocriptine may be beneficial in treating SLE. In NZB/NZW mice, bromocriptine was beneficial and prolonged life. Bromocriptine therapy favorably modified disease in human SLE. In a preliminary open-label study, SLE patients treated with bromocriptine for 6 months had significant improvement in disease activity. These responses were corroborated by masted therapeutic studies. Daily treatment with low-dose bromocriptine prevented lupus flares, and bromocriptine was as effective as hydroxychloroquine in treating active nonorgan-threatening disease. The reports of the efficacy of bromocriptine treatment of SLE are encouraging. Additional studies may confirm the findings reported in this review and may lead to further use of hormonal modification to treat lupus and other autoimmune diseases. For the present, it is important to understand that treatment with dopamine agonists such as bromocriptine is experimental and best confined to therapeutic trials. In the experience of the authors, bromocriptine should not be relied on to treat severe life-threatening autoimmune disease. If bromocriptine is used to treat SLE and is then discontinued, the patient should be observed carefully for rebound hyperprolactinemia and the development of a lupus flare. GnRH is produced by lymphocytes and exerts immunomodulatory actions. Thus, GnRH resembles a cytokine. GnRH can be shown to exert gender-restricted immune actions in vitro and in vivo. The authors' preliminary observations are consistent with the possibility that gender-related differences in expression of the GnRH receptor or in GnRH signal transducers may contribute to gender-related differences in immune responsiveness to GnRH. These differences in G proteins may contribute to the gender-related differences in immunity and expression of autoimmune disease.

Menopause, oestrogens and arthritis

The menopause coincides with the appearance of many of the common arthritic conditions and with the lessening of severity of others such as SLE. The hormonal changes that occur may modulate these diseases. Thus, hormonal manipulation may have either beneficial or detrimental effects on the incidence and activity of a number of common joint diseases. We review the evidence regarding the effect of the menopause and oestrogen replacement therapy on the pathogenesis, incidence and prevalence and disease activity of osteoarthritis, rheumatoid arthritis, systemic lupus erythematosus and carpal tunnel syndrome.

Complex associations between HLA-DRB1 genes and female rheumatoid arthritis: results from a prospective study

We followed 138 Spanish patients (37 men and 101 women) with rheumatoid arthritis (RA) to analyze whether patient sex influenced the HLA-DRB1 associations with disease susceptibility. Results showed that, although a high increase of the shared epitope (SE) was observed in both genders, distribution of HLA-DRB1 specificities differs from males to females: DR1 was increased among male patients, whereas DR4 as well as DR10 were preferentially associated with female RA. To further explore whether this phenomenon operates either on susceptibility or on disease progression, 82 patients (25 males and 57 females) among the whole group were followed during the first 8 to 10 years of their disease. Results from this prospective study showed that the association of the SE with radiological disease severity was found in both male and female patients, although it was stronger among the latter group. Interestingly, DR1- as well as DR4-related alleles contributed to the high frequency of SE among female patients with early small-joints severe RA and/or long-term large-joint erosions. These results suggest that HLA polymorphism might be involved in RA pathogenesis through two mechanisms: (a) in combination with patient sex, operating in disease induction; and (b) independent of patient sex, influencing disease severity and progression.

Pregnancy and early onset pauciarticular juvenile chronic arthritis

OBJECTIVES

To study interaction of early onset pauciarticular juvenile chronic arthritis (EOP-JCA) and pregnancy in the Polish population, in particular to confirm the ameliorating effect of pregnancy on disease activity reported by others and to analyse the factors that govern the occurrence of postpartum flare, with emphasis on the potential role of breast feeding.

METHODS

The reproductive outcome and disease status in 39 adult women with history of EOP- JCA was examined by means of a questionnaire and an interview. In all patients the disease onset occurred before the 6th birthday, 19 had persistent pauciarticular JCA (PeEOP-JCA) and 20 had extended pauciarticular JCA (ExEOP-JCA).

RESULTS

23 women had at least one successful pregnancy, seven had unsuccessful pregnancies but all of them had also one or more successful pregnancies. Among those who have never been pregnant (n=16) there was a higher frequency of eye disease and ExEOP-JCA compared with the rest of the group. In almost all cases pregnancy was associated with remission of disease activity, however a postpartum flare appeared after 22 pregnancies (52%). The flares were more frequent in women who had an active disease before pregnancy, had a flare after a previous pregnancy and/or were breast feeding.

CONCLUSIONS

In EOP-JCA patients pregnancy generally has a good outcome and induces amelioration of disease activity. After delivery, however, a flare of disease often appears, especially in women who were breast feeding, had a postparum flare previously or had an active disease before pregnancy. The pattern of interaction between disease and pregnancy found in EOP-JCA makes EOP-JCA similar in this respect to RA, but different from systemic lupus erythematosus and ankylosing spondylitis.

Prolactin and prolactin-like polypeptides in rheumatoid arthritis

A bidirectional communication network exists between the neuroendocrine and immune systems, and a dysfunctional communication may contribute to the development of autoimmune diseases in various species, including humans. Experimental, epidemiological, and clinical data suggest that breast feeding and hyperprolactinemia constitute a risk factor for the development of diseases with autoimmune components, including rheumatoid arthritis (RA). We hypothesized that the anterior pituitary hormone prolactin (Prl) and locally produced Prl-like polypeptides may act as endocrine, autocrine, and paracrine regulators of synovial cell functions. They may participate not only in enhancing T-lymphocyte immune reactivity, but also in the exacerbation of RA lesions through their influence on synovial fibroblasts. In RA synovial tissue, Prl-like polypeptides could participate in a bidirectional communication between immunocytes and fibroblasts. Both Prl and Prl-like polypeptides might act via proto-oncogenes and transcriptional factors, leading to cell proliferation, i.e., synovial tissue hyperplasia, neo-angiogenesis, and the production of catabolic enzymes such as matrix metalloproteinases and cathepsins. In such cases, they could represent important regulators of the T-cell independent mechanism of joint destruction.

Macrophage Fcgamma receptors expression is altered by treatment with dopaminergic drugs

Macrophage Fcgamma receptors have an important role in host defense and the pathophysiology of immune mediated disorders. Alteration of splenic macrophage Fcgamma receptors expression predisposes to severe infection. Inhibition or blockade of splenic macrophage Fcgamma receptors is one of the mechanisms by which immune cytopenias improve. Dopaminergic drugs have clinically significant regulatory functions on the immune response. Using an experimental model in the guinea pig we assessed the effect of commonly used dopaminergic drugs on the expression of macrophage Fcgamma receptors. Three dopa-antagonists, bromocryptine, leuprolide, and pergolide, and seven dopa-antagonists, chlorpromazine, SCH 23390, metochlopramide, sulpiride, veralipride, alizapride, and cisapride, were studied. Following guinea pig treatment with dopaminergic drugs, the clearance of IgG-sensitized RBCs in vivo, the in vitro binding of IgG-sensitized RBCs by isolated splenic macrophages and flow cytometry with monoclonal antibodies were performed. Treatment with dopa-agonists enhanced the clearance of IgG-sensitized RBCs, the in vitro binding of IgG-sensitized RBCs by isolated splenic macrophages, and the cell surface expression of both macrophage Fcgamma receptors, and vice versa, dopa-antagonists impaired macrophage Fcgamma receptors expression. Macrophage FcgammaR1,2 was more sensitive than FcgammaR2 to such dopaminergic effect. These alterations of macrophage Fcgamma receptors expression are mediated by both D1 and D2 dopamine receptors, with a major participation of D2 receptors. Dopaminergic drugs alter the clearance of IgG-coated cells by an effect at the expression of splenic macrophage Fcgamma receptors.

Hypophyseal-pituitary-adrenal axis in autoimmune and rheumatic diseases

This article discusses the effects of sex steroids and anterior pituitary hormones on the immune system. Data from clinical and experimental studies on the effects of CRH, FSH, LH, and prolactin are reviewed. This is followed by a summary of results from our studies on the effects of FSH, LH, and prolactin on PBMC, CD4+ cells, and CD8+ cells in vitro.

Spondyloarthritides in females

Few studies have been performed regarding clinical, radiological and prognostic features of females with spondyloarthropathies other than ankylosing spondylitis (AS). In AS, clinical manifestations appear similar in men and women, whereas radiological features appear more frequent and severe in males. However, no consistent differences in outcome and mortality between men and women have been disclosed. Although fetal outcome is not compromised in women with spondyloarthropathy (SpA), the interaction of pregnancy and SpA has been studied in detail only in AS. Spinal disease is unchanged while peripheral arthritis and uveitis are suppressed during childbearing. Due to possible maternal and fetal side-effects, NSAIDs must be discontinued during the last 8 weeks of pregnancy, but during lactation several NSAIDs can be used. Treatment with sulphasalazine is compatible with pregnancy and lactation. Children of AS patients exhibit a slightly increased risk of developing SpA later in life.

Allelic markers close to prolactin are associated with HLA-DRB1 susceptibility alleles among women with rheumatoid arthritis and systemic lupus erythematosus

OBJECTIVE

To investigate linkage disequilibrium between HLA-DRB1 disease susceptibility alleles and microsatellite markers close to the prolactin gene, among women with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) and normal controls.

METHODS

DNA from 89 women with RA, 76 women with SLE, and 94 controls was typed for HLA-DRB1 status and D6S422 and D6S285, 2 highly polymorphic microsatellite markers close to the prolactin gene. RA patients were stratified by DRB1*0401 status, and SLE patients were stratified by *0301 status.

RESULTS

There was an excess frequency of D6S422*1 among SLE patients with DRB1*0301 (odds ratio [OR] 3.1). The frequency of this allele was also slightly in excess among RA patients with DRB1*0401 (OR 1.9). D6S285*5 was also in excess among female RA patients with DRB1*0401 (OR 3.5), and was slightly increased among female SLE patients with DRB1*0301. None of these alleles were found to be increased among *0401-positive or *0301-positive controls.

CONCLUSION

These data indicate that there may be linkage disequilibrium between HLA-DRB1 alleles and microsatellite marker alleles close to the prolactin gene among women with RA and SLE. This suggests the possibility of extended haplotypes encoding for HLA-DRB1 susceptibility and high prolactin production, which contribute to susceptibility to both RA and SLE.

Can we predict aggressive disease?

This chapter will describe the reasons why prognostic factors that predict aggressive disease are helpful and what the problems are in interpreting studies in this field. A summary of cohort studies on prognosis of patients with early rheumatoid arthritis are presented. This is done separately for studies predicting radiographic damage, functional outcome and mortality. The overall conclusions of these studies and the value they have for the clinician are demonstrated.