Estrogen attenuates the spondyloarthritis manifestations of the SKG arthritis model

Fertility issues in women of childbearing age with spondyloarthritis

The topic of fertility in women with spondyloarthritis (SpA) has been scarcely investigated to date. Recent systematic reviews and registry studies have brought renewed attention to the plight of women of childbearing age with rheumatic diseases, in particular SpA. Fertility may be impacted by physical impairment, hormonal imbalances and psychological distress. Several studies observed a reduction in anti-Müllerian hormone in women with SpA, reflecting a reduced ovarian reserve (OR). Furthermore, disease activity and the use of certain therapies can alter fertility, and this is reflected in a prolonged time-to-pregnancy (TTP), a validated outcome measure that can evaluate the status of subfertility. The employment of glucocorticoids or non-steroidal anti-inflammatory drugs has also been linked to reduced fertility, whereas the use of biologics, especially tumour necrosis factor inhibitors (TNFi), is not associated with a prolonged TTP. In all women of childbearing age with rheumatic diseases, preconception counselling is paramount, and a referral to a reproductive specialist should be considered in the presence of multiple factors that may influence fertility. A comprehensive evaluation involving a multidisciplinary team of rheumatologists, gynaecologists, and often psychologists is warranted. In this narrative review, we collected the currently available literature focusing on fertility issues in women affected by SpA, providing data on fertility outcomes, hormonal imbalance, and therapeutic concerns.

Clinical, Laboratory, and Imaging Features Between Men and Women With Axial Spondyloarthritis in a Specialized Center in Argentina

OBJECTIVES

The aims were to estimate the frequency of axial spondyloarthritis (axSpA) in women and to analyze the clinical, laboratory, and imaging differences with respect to men at the time of diagnosis.

METHODS

Consecutive patients older than 18 years with a diagnosis of axSpA admitted to the "Reumacheck" SpA program were included between 2017 and 2022. At baseline, all patients underwent clinical assessment, laboratory tests including C-reactive protein and human leukocyte antigen B27, and imaging (plain radiography and magnetic resonance imaging of sacroiliac joints, and ultrasound of heel entheses). All evaluators were blinded to the results of the other evaluations.

RESULTS

One hundred sixteen patients with a diagnosis of axSpA were included. The frequency at diagnosis in women was 61.55%. In the univariate analysis, the significant differences between women and men at diagnosis of axSpA were good response to nonsteroidal anti-inflammatory drugs, elevated C-reactive protein, New York Criteria (+), enthesis ultrasound (+), years of education, number of swollen joints, erythrosedimentation rate, and the very low frequency of bone bridges in the magnetic resonance imaging of the sacroiliac joints. In the logistic regression analysis, the dependent variable was "men," and the only feature that was independently associated was having radiographic compromise according to the New York criteria (odds ratio, 2.6).

CONCLUSIONS

The frequency of axSpA in women was 61.55%; clinical, laboratory, and imaging differences were observed. Women experienced less radiographic compromise.

Letrozole-induced inflammatory arthritis and tendinopathy in pediatric rheumatology setting

Musculoskeletal symptoms associated with the use of aromatase inhibitors are a well-known side effect of these drugs and are more prevalent in postmenopausal women. Aromatase inhibitor-associated symptoms are not overt inflammatory processes so are described as arthralgia syndrome. In contrast, aromatase inhibitor-associated inflammatory conditions such as myopathies, vasculitis, and rheumatoid arthritis were also reported. To our knowledge, inflammatory arthritis or tendinopathy associated with aromatase inhibitors were not reported in children despite their increased off-label use in the pediatric setting. Herein, we report a girl with inflammatory arthritis and tendinopathy associated with letrozole treatment.

A comparison of the clinical characteristics and quality of life of male and female patients with non-radiographic axial spondyloarthritis

OBJECTIVE

The aim of this study was to compare the clinical characteristics and quality of life of male and female patients with non-radiographic axial spondyloarthritis (nraxSpA) to determine the differences and similarities.

PATIENTS AND METHODS

The study included 100 patients, comprising 50 males and 50 females, aged 18-65 years, who presented at the Rheumatology Clinic and were diagnosed with nr-axSpA according to the Assessment of Spondyloarthritis International Society (ASAS) criteria. The data of patient age, gender, body mass index, disease duration, and drugs used were recorded. Disease activity was evaluated with the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), mobility with the Bath Ankylosing Spondylitis Metrology Index (BASMI), functional status with the Bath Ankylosing Spondylitis Functional Index (BASFI), enthesitis with the Maastricht Ankylosing Spondylitis Enthesitis Score (MASES), and quality of life with the Ankylosing Spondylitis Quality of Life (ASQoL). The patients with nr- axSpA were separated into groups as male and female, and the demographic and clinical data were compared.

RESULTS

The mean age of female patients was determined to be statistically significantly higher than that of the male patients (39.04 ± 0.70 vs. 34.28 ± 9.26 years, p:0.014). A statistically greater number of male patients were smokers (p:0.007). The disease duration and time since diagnosis were determined to be significantly longer in females than in males (p:0.029, p:0.004). Peripheral arthritis was determined at a significantly higher rate in females (p < 0.001). The MASES score was 2.66 ± 3.46 in females and 0.52 ± 1.03 in males, and the difference was statistically significant (p < 0.001). The BASDAI score was significantly higher in females (3.74 ± 2.35) than in males (2.88 ± 1.95) (p:0.05). No statistically significant difference was determined between the two groups in respect of BASFI, BASMI, ASQoL, and other parameters.

CONCLUSION

The results showed older age, longer disease duration and time to diagnosis, higher rates of peripheral arthritis, and higher MASES and BASDAI scores in the female patients. Thus, there are some differences between male and female patients. Further studies should determine what kind of changes these differences will make in the clinical status, follow-up and treatment of patients.

Revealing mechanism of Methazolamide for treatment of ankylosing spondylitis based on network pharmacology and GSEA

Methazolamide is a carbonic anhydrase (CA) inhibitor with satisfactory safety. Our previous studies have demonstrated the elevation of CA1 expression and the therapeutic effect of Methazolamide in Ankylosing spondylitis (AS). In this study, we explored the pathogenic role of CA1 and the pharmacological mechanism of Methazolamide in AS through Gene Set Enrichment Analysis (GSEA) and network pharmacology. Seven out of twelve CA1 related gene sets were enriched in AS group. CA1 was core enriched in above seven gene sets involving zinc ion binding, arylesterase activity and one carbon metabolic process. Functional analysis of the candidate target genes obtained from the intersection of AS associated genes and Methazolamide target genes indicated that Methazolamide exerts therapeutic effects on AS mainly through inflammatory pathways which regulate the production of tumor necrosis factor, IL-6 and nitric oxide. PTGS2, ESR1, GSK3β, JAK2, NOS2 and CA1 were selected as therapeutic targets of Methazolamide in AS. Molecular docking and molecular dynamics simulations were performed successfully. In addition, we innovatively obtained the intersection of Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses and GSEA results, and found that 18 GO terms and 5 KEGG terms were indicated in the pharmacological mechanism of Methazolamide in AS, involving bone mineralization, angiogenesis, inflammation, and chemokine signaling pathways. Nevertheless, validation for these mechanisms is needed in vivo/vitro experiments.

Estradiol is a key candidate for treating Ankylosing Spondylolisthesis with Traditional Chinese Medicine

Some Traditional Chinese Medicine (TCM) has shown anti-inflammatory and immunosuppressive effects on Ankylosing Spondylitis (AS) treatment. Wan Bikang (WBK) and Wan Biqing (WBQ) are two traditional empirical formulas for AS. However, the mechanism of their effects on AS is largely unknown. This study deciphered the underlying common molecular mechanisms of these TCM treatments for AS. The ultra-high-performance liquid chromatography-triple/time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) assays were employed to detect herbal ingredients. Target proteins of herbal ingredients were identified by ChEMBL Database. To infer the relationships between ingredients and AS-related proteins, network pharmacology was employed. Protein-protein interaction (PPI) network and core target analyses were carried out with tools Cytoscape and STRING. To find out the molecular basis and target of AS, molecular docking and an in vitro experiment were also conducted. It is found that estradiol may participate in the treatment of AS via the inhibition of inflammatory factors, and Estrogen Receptor 1 (ESR1) appears to be a key target. This research offers insight into the therapeutic mechanism of TCM formulas for AS and furthers our understanding of TCM pharmacology.

Causal relationship between endometriosis with infertility and ankylosing spondylitis

Retrospective studies have identified an increased risk of ankylosing spondylitis (AS) in endometriosis patients. The purpose of this study was to investigate the causal relationship between clinical phenotypes of endometriosis and AS using mendelian randomized analysis (MR). MR was performed using data from genome-wide association studies (GWASs). Heterogeneity, pleiotropy and sensitivity analyses were performed to evaluate the robustness of the results by MR Egger and inverse variance weighted (IVW), leave-one-out analysis. IVW, IVW-MRE (inverse variance weighted multiplicative random effects), weighted median and MR Egger were used to explore the relationship between endometriosis and AS. The IVW analysis showed a causal relationship between infertile endometriosis and AS (OR = 0.8334, P = 0.02191), and the same result was observed with IVW-MRE (OR = 0.8334, P = 0.0007933). However, further stratified analysis showed that no matter which statistical method was used, ovarian endometriosis (IVW: OR = 0.1662, P = 0.4986; IVW-MRE: OR = 0.1662, P = 0.4986; MR Egger: OR = - 0.9577, P = 0.2798; Weighted median: OR = 0.2628, P = 0.3452), pelvic peritoneum endometriosis (IVW: OR = 0.4363, P = 0.225; IVW-MRE: OR = 0.4363, P = 0.225, MR Egger: OR = 4.159, P = 0.1705; Weighted median: OR = 0.4112, P = 0.2714), rectovaginal endometriosis (IVW: OR = 0.1365, P = 0.805; IVW-MRE: OR = 0.1365, P = 0.805) there was no causal relationship between endometriosis and AS. This study suggested that patients with infertility endometriosis are at increased risk for AS. This study supports clinicians to pay more attention to the occurrence of AS in endometriosis patients with infertility.

Single-Cell Genomics for Investigating Pathogenesis of Inflammatory Diseases

Recent technical advances have enabled unbiased transcriptomic and epigenetic analysis of each cell, known as "single-cell analysis". Single-cell analysis has a variety of technical approaches to investigate the state of each cell, including mRNA levels (transcriptome), the immune repertoire (immune repertoire analysis), cell surface proteins (surface proteome analysis), chromatin accessibility (epigenome), and accordance with genome variants (eQTLs; expression quantitative trait loci). As an effective tool for investigating robust immune responses in coronavirus disease 2019 (COVID-19), many researchers performed single-cell analysis to capture the diverse, unbiased immune cell activation and differentiation. Despite challenges elucidating the complicated immune microenvironments of chronic inflammatory diseases using existing experimental methods, it is now possible to capture the simultaneous immune features of different cell types across inflamed tissues using various single-cell tools. In this review, we introduce patient-based and experimental mouse model research utilizing single-cell analyses in the field of chronic inflammatory diseases, as well as multi-organ atlas targeting immune cells.

An update on animal models of intervertebral disc degeneration and low back pain: Exploring the potential of artificial intelligence to improve research analysis and development of prospective therapeutics

Animal models have been invaluable in the identification of molecular events occurring in and contributing to intervertebral disc (IVD) degeneration and important therapeutic targets have been identified. Some outstanding animal models (murine, ovine, chondrodystrophoid canine) have been identified with their own strengths and weaknesses. The llama/alpaca, horse and kangaroo have emerged as new large species for IVD studies, and only time will tell if they will surpass the utility of existing models. The complexity of IVD degeneration poses difficulties in the selection of the most appropriate molecular target of many potential candidates, to focus on in the formulation of strategies to effect disc repair and regeneration. It may well be that many therapeutic objectives should be targeted simultaneously to effect a favorable outcome in human IVD degeneration. Use of animal models in isolation will not allow resolution of this complex issue and a paradigm shift and adoption of new methodologies is required to provide the next step forward in the determination of an effective repairative strategy for the IVD. AI has improved the accuracy and assessment of spinal imaging supporting clinical diagnostics and research efforts to better understand IVD degeneration and its treatment. Implementation of AI in the evaluation of histology data has improved the usefulness of a popular murine IVD model and could also be used in an ovine histopathological grading scheme that has been used to quantify degenerative IVD changes and stem cell mediated regeneration. These models are also attractive candidates for the evaluation of novel anti-oxidant compounds that counter inflammatory conditions in degenerate IVDs and promote IVD regeneration. Some of these compounds also have pain-relieving properties. AI has facilitated development of facial recognition pain assessment in animal IVD models offering the possibility of correlating the potential pain alleviating properties of some of these compounds with IVD regeneration.

Intervertebral disc degeneration and how it leads to low back pain

The purpose of this review was to evaluate data generated by animal models of intervertebral disc (IVD) degeneration published in the last decade and show how this has made invaluable contributions to the identification of molecular events occurring in and contributing to pain generation. IVD degeneration and associated spinal pain is a complex multifactorial process, its complexity poses difficulties in the selection of the most appropriate therapeutic target to focus on of many potential candidates in the formulation of strategies to alleviate pain perception and to effect disc repair and regeneration and the prevention of associated neuropathic and nociceptive pain. Nerve ingrowth and increased numbers of nociceptors and mechanoreceptors in the degenerate IVD are mechanically stimulated in the biomechanically incompetent abnormally loaded degenerate IVD leading to increased generation of low back pain. Maintenance of a healthy IVD is, thus, an important preventative measure that warrants further investigation to preclude the generation of low back pain. Recent studies with growth and differentiation factor 6 in IVD puncture and multi-level IVD degeneration models and a rat xenograft radiculopathy pain model have shown it has considerable potential in the prevention of further deterioration in degenerate IVDs, has regenerative properties that promote recovery of normal IVD architectural functional organization and inhibits the generation of inflammatory mediators that lead to disc degeneration and the generation of low back pain. Human clinical trials are warranted and eagerly anticipated with this compound to assess its efficacy in the treatment of IVD degeneration and the prevention of the generation of low back pain.

Sex- and gender-related differences in psoriatic arthritis

Psoriatic arthritis (PsA) is an inflammatory musculoskeletal disease with a chronic, progressive course. Various aspects of PsA, including its clinical features, disease course and response to treatment, are influenced by sociodemographic characteristics of the patient. This includes patient sex, the biological attributes associated with being male or female, and gender, a sociocultural construct that comprises attitudes, traits and behaviours associated with being a man or a woman. An understanding of sex- and gender-related differences in PsA, as well as their underlying mechanisms, is therefore important for individualized care. In this narrative review, the influence of sex and gender on PsA manifestation and course, patient function and quality of life, and their association with comorbidities are described. Sex- and gender-related disparities in response to advanced therapies and their potential underlying mechanisms are delineated. Differences in pathophysiological mechanisms between male and female patients including genetics, immune and hormonal mechanisms are discussed. Finally, fertility and pregnancy outcomes in PsA are outlined. By adopting sex and gender lenses, this review is aimed at highlighting key differences between male and female patients with PsA and uncovering mechanisms underlying these differences, ultimately promoting individualized care of men and women with PsA and informing future research in this area.

No increased risk of alopecia in ankylosing spondylitis patients: A population-based cohort study in Taiwan

AIM

To investigate the association between ankylosing spondylitis (AS) and alopecia.

METHODS

In this cohort study, data from over 1 000 000 patients in the Taiwan Longitudinal Health Insurance Database were extracted. We selected newly diagnosed (outpatient department visit three or more times or admission at least once) patients with AS (ICD-9-CM = 720.0) from 2000 to 2012. For the non-AS comparison group, patients never diagnosed with AS were chosen from 1999 to 2013. In all, 3640 AS patients and 14 560 non-AS controls were selected. Cox proportional hazard model and Kaplan-Meier analysis were used to present the results. The adjusted hazard ratio (HR) in the Cox proportional hazard model was adjusted for age, sex, hypertension, hyperlipidemia, diabetes, atopic dermatitis, and mental disorder.

RESULTS

No increased risk of alopecia in AS patients was shown in the Cox proportional hazard model (crude HR 1.16, P = 0.595; adjusted HR 1.16, P = 0.599). Negative results are found as well in subgroup analysis of different age, sex (age 20-40 y: HR 1.03, P = 0.925; Age ≥40 y: HR 1.49, P = 0.406; Female: HR 1.17, P = 0.759; Male: HR 1.15, P = 0.667), and phenotypes of alopecia (androgenetic alopecia: HR 1.19, 95% confidence interval [CI] 0.58-2.41; alopecia areata: HR 0.98, 95% CI 0.37-2.62). A significant positive correlation is found between atopic dermatitis and alopecia (adjusted HR 8.05, P = 0.039).

CONCLUSION

In this population-based cohort study, we found no association of risk of alopecia and AS.

Spondyloarthritides: Theories and beyond

Spondyloarthritides (SpA) are a family of interrelated rheumatic disorders with a typical disease onset ranging from childhood to middle age. If left untreated, they lead to a severe decrease in patients' quality of life. A succesfull treatment strategy starts with an accurate diagnosis which is achieved through careful analysis of medical symptoms. Classification criterias are used to this process and are updated on a regular basis. Although there is a lack of definite knowledge on the disease etiology of SpA, several studies have paved the way for understanding plausible risk factors and developing treatment strategies. The significant increase of HLA-B27 positivity in SpA patients makes it a strong candidate as a predisposing factor and several theories have been proposed to explain HLA-B27 driven disease progression. However, the presence of HLA-B27 negative patients underlines the presence of additional risk factors. The current treatment options for SpAs are Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), TNF inhibitors (TNFis), Disease-Modifying Anti-Rheumatic Drugs (DMARDs) and physiotherapy yet there are ongoing clinical trials. Anti IL17 drugs and targeted synthetic DMARDs such as JAK inhibitors are also emerging as treatment alternatives. This review discusses the current diagnosis criteria, treatment options and gives an overview of the previous findings and theories to clarify the possible contributors to SpA pathogenesis with a focus on Ankylosing Spondylitis (AS) and enthesitis-related arthritis (ERA).

Immunopathophysiology of Juvenile Spondyloarthritis (jSpA): The "Out of the Box" View on Epigenetics, Neuroendocrine Pathways and Role of the Macrophage Migration Inhibitory Factor (MIF)

Juvenile spondyloarthritis (jSpA) is a an umbrella term for heterogeneous group of related seronegative inflammatory disorders sharing common symptoms. Although it mainly affects children and adolescents, it often remains active during adulthood. Genetic and environmental factors are involved in its occurrence, although the exact underlying immunopathophysiology remains incompletely elucidated. Accumulated evidence suggests that, in affected patients, subclinical gut inflammation caused by intestinal dysbiosis, is pivotal to the future development of synovial-entheseal complex inflammation. While the predominant role of IL17/23 axis, TNF-α, and IL-7 in the pathophysiology of SpA, including jSpA, is firmly established, the role of the cytokine macrophage migration inhibitory factor (MIF) is generally overlooked. The purpose of this review is to discuss and emphasize the role of epigenetics, neuroendocrine pathways and the hypothalamic-pituitary (HPA) axis, and to propose a novel hypothesis of the role of decreased NLRP3 gene expression and possibly MIF in the early phases of jSpA development. The decreased NLRP3 gene expression in the latter, due to hypomethylation of promotor site, is (one of) the cause for inflammasome malfunction leading to gut dysbiosis observed in patients with early jSpA. In addition, we highlight the role of MIF in the complex innate, adaptive cellular and main effector cytokine network, Finally, since treatment of advanced bone pathology in SpA remains an unmet clinical need, I suggest possible new drug targets with the aim to ultimately improve treatment efficacy and long-term outcome of jSpA patients.

Genetics, Epigenetics, and Gender Impact in Axial-Spondyloarthritis Susceptibility: An Update on Genetic Polymorphisms and Their Sex Related Associations

Spondyloarthritis (SpA) is a group of chronic inflammatory rheumatic disease that can be divided into predominantly axial or predominantly peripheral involvement, with or without associated psoriasis, inflammatory bowel disease or previous infection. Axial SpA (axSpA) encompasses ankylosing spondylitis (AS) with radiological sacroiliitis, and a type without radiographic sacroiliitis, called “non-radiographic axial SpA” (nr-axSpA). Males and females show large differences in their susceptibility to SpA, such as distinctions in clinical patterns, phenotypes and in therapeutical response, particularly to TNF inhibitors (TNFi). Several studies indicate that AS women have doubled risk to failure TNFi compared with males. This diversity in drugs’ efficacy among women and men may be caused by differences in the balance of sex hormones and in gene-specific expression likely triggered by X-chromosome instability and gene-specific epigenetic modifications. Evidence reported that polymorphisms in microRNAs on X- and other chromosomes, such as miR-146a, miR-155, miR-125a-5p, miR-151a-3p and miR-22-3p, miR-199a-5p could be involved in the different clinical presentation of SpA, as well as disease activity. In addition, association with non−response to TNFi treatment and presence of IRAK3 and CHUCK genes in SpA patients was recently detected. Finally, polymorphisms in genes involved in IL-23/IL-17 pathway, such as in drug pharmacodynamics and pharmacokinetics may have a role in response to TNFi, IL17i, and IL23i. A major understanding of genomic variability could help in the development of new therapeutic targets or in taking advantages of different mechanisms of action of biological drugs. Moving from the multifactorial etiology of disease, the present review aims at evaluating genetic and epigenetic factors and their relationship with sex and bDMARDs response, helping to investigate the different expression among males and females of genes on X- and other chromosomes, as well as mi-RNA, to highlight relationships between sex and occurrence of specific phenotypes and symptoms of the disease. Moreover, the role of the epigenetic modification in relation to immune-regulatory mechanisms will be evaluated.

Selective estrogen receptor modulator lasofoxifene suppresses spondyloarthritis manifestation and affects characteristics of gut microbiota in zymosan-induced SKG mice

Ankylosing spondylitis is a male-predominant disease and previous study revealed that estrogens have an anti-inflammatory effect on the spondyloarthritis (SpA) manifestations in zymosan-induced SKG mice. This study aimed to evaluate the effect of selective estrogen receptor modulator (SERM) lasofoxifene (Laso) on disease activity of SpA. Mice were randomized into zymosan-treated, zymosan + 17β-estradiol (E2)-treated, and zymosan + Laso-treated groups. Arthritis was assessed by ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) small-animal positron emission tomography/computed tomography and bone mineral density (BMD) was measured. Fecal samples were collected and 16S ribosomal RNA gene sequencing was used to determine gut microbiota differences. Both zymosan + E2-treated mice and zymosan + Laso-treated mice showed lower arthritis clinical scores and lower ¹⁸F-FDG uptake than zymosan-treated mice. BMD was significantly higher in zymosan + E2-treated mice and zymosan + Laso-treated mice than zymosan-treated mice, respectively. Fecal calprotectin levels were significantly elevated at 8 weeks after zymosan injection in zymosan-treated mice, but it was not significantly changed in zymosan + E2-treated mice and zymosan + Laso-treated mice. Gut microbiota diversity of zymosan-treated mice was significantly different from zymosan + E2-treated mice and zymosan + Laso-treated mice, respectively. There was no significant difference in gut microbiota diversity between zymosan + E2-treated mice and zymosan + Laso -treated mice. Laso inhibited joint inflammation and enhanced BMD in SKG mice, a model of SpA. Laso also affected the composition and biodiversity of gut microbiota. This study provides new knowledge regarding that selected SpA patients could benefit from SERM treatment.

The Emerging Roles of Endocrine Hormones in Different Arthritic Disorders

The relationship between endocrine hormones and the spectrum of rheumatic conditions has long been discussed in the literature, focusing primarily on sexual hormones, such as estrogens, androgens, prolactin (PRL). Estrogens are indeed involved in the pathogenesis of the main inflammatory arthritis thanks to their effects on the immune system, both stimulatory and inhibitory. The PRL system has been discovered in synovial tissue of rheumatoid arthritis (RA) and psoriatic arthritis (PsA), patients and has been propose as a new potential therapeutic target. Besides sexual hormones, in the last years scientific interest about the crosstalk of immune system with other class of hormones has grown. Hormones acting on the bone tissue (i.e. parathyroid hormone, vitamin D) and modulators of the Wnt pathway (i.e. Dickkopf-1) have been demonstrated to play active role in inflammatory arthritis course, defining a new field of research named osteoimmunology. PTH, which is one of the main determinants of Dkkopf-1, plays a crucial role in bone erosions in RA and a correlation between PTH, Trabecular Bone Score (TBS) and disease activity has been found in ankylosing spondylitis (AS). In PSA is under studying the interaction among IL-17 and bone metabolism. The purpose of this review is to discuss and summarize the recent data about the interaction between endocrine hormone and immune system in the main rheumatic disorders, covering in particular the role of bone-related hormones and cytokines. We will describe this relationship from a biochemical, diagnostic and therapeutic perspective, with a particular focus on RA, PsA and AS.

The Effects of Sex and Estrogen on Radiographic Progression of Ankylosing Spondylitis in Korean Patients

Objective

Ankylosing spondylitis (AS) is a chronic inflammatory disease with obvious male preponderance Males show more severe radiographic manifestations compared with females This study aimed to evaluate the effects of sex and estrogen on the radiographic progression of AS.

Methods

A total of 101 patients with AS were included in this study All of the radiographs were scored using the modified Stoke AS Spine Score (mSASSS) Serum levels of 17β-estradiol (E2), dickkopf-1 (Dkk1), and leptin were detected by enzyme-linked immunosorbent assay The generalized estimating equations model was used to evaluate factors associated with spinal radiographic progression.

Results

The mean age at disease onset was 273±107 years, and 16 patients (158%) were female In the multivariable analysis, body mass index (β-coefficient=012; p=0047) and levels of Dkk1 (β-coefficient=-011; p<0001), and female (β-coefficient=-140; p=0001) were associated with radiographic progression Among male patients with AS, baseline C-reactive protein (β=011; p=0005) and mSASSS (β=021; p=0030) were also associated with radiographic progression E2 and leptin levels were not significantly related to the radiographic progression.

Conclusion

Although female patients were associated with less radiographic progression in AS, there was no significant relationship between serum estrogen level and radiographic progression Results of current study suggests that genetic factors or other environmental factors associated with female may influence radiographic progression in patients with AS.

Understanding differences between men and women with axial spondyloarthritis

Axial spondyloarthritis (axSpA) is a chronic inflammatory immune-mediated disease resulting in inflammatory low back pain and other inflammatory manifestations in peripheral joints and entheses. AxSpA encompasses both ankylosing spondylitis (AS), in which patients present with definitive sacroiliitis visible on radiographic imaging, as well as nonradiographic axSpA (nr-axSpA), in which such changes may not be discernable. Emerging evidence suggests that women and men experience axSpA differently. Although the prevalence of AS is approximately 2- to 3- fold higher in men than in women, nr-axSpA occurs with roughly equal frequency in women and men. The goal of this review is to increase awareness of sex differences in axSpA by exploring the distinct manifestations of disease and disease characteristics in women, the overall clinical burden, recommendations for diagnosis, and potential treatment options. We summarize and contextualize the results of recent studies that illuminate sex differences in nr-axSpA and AS, including differences in disease manifestation and progression. It is important that sex differences in axSpA are understood and considered when diagnosing and treating the spectrum of axSpA, including AS and nr-axSpA.

Can the Second to Fourth Digit Ratio (2D : 4D) Be a Marker to Determine Ankylosing Spondylitis Disease Activity?

Objective

The length ratio of the index finger (2D) to the ring finger (4D) (2D : 4D ratio) is considered a biomarker of prenatal sex hormone exposure. The 2D : 4D ratio is influenced by prenatal androgen and estrogen levels. Because ankylosing spondylitis (AS) influences men more frequently and severely than women, androgens are proposed to be related to AS pathogenesis. Estrogens have immune-modulating effects and reduce AS disease activity. The aim of this study was to assess the relationship between 2D : 4D ratio and AS disease activity.

Material and Methods

In this study, 167 (43 female) patients diagnosed with AS were studied. The lengths of the second and fourth fingers were measured using a digital caliper. The 2D : 4D ratio was found by dividing the length of the second finger by the length of the fourth finger. AS disease activity was assessed with the Turkish version of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). AS functional status was assessed with Bath Ankylosing Spondylitis Functional Index (BASFI). L-Schober, tragus to wall distance, finger to floor distance, and chest expansion were used to evaluate mobility.

Results

In female patients, the right hand 2D : 4D ratios were higher than those in male patients. Biologic drug use was more frequent in males. The BASDAI scores were higher in female patients than in male patients. There were significant negative correlations between right and left hand 2D : 4D ratio and BASFI and BASDAI in female patients. There was no significant correlation between the 2D : 4D ratio and BASFI or BASDAI in male patients. We found a positive correlation between L-Schober and right hand 2D : 4D and a negative correlation between the left hand 2D : 4D ratio and finger to floor distance in female patients with AS.

Conclusion

The 2D : 4D ratio of the right and left hand was low in female patients with high BASFI and BASDAI and low spinal mobility (L-Schober) was also linked to low female 2D : 4D. The lack of strong associations between 2D : 4D and AS in male patients may have resulted from their higher use of biologics.

Gender Differences in Axial Spondyloarthritis: Women Are Not So Lucky

PURPOSE OF REVIEW

Ankylosing spondylitis (AS) was historically seen as a predominantly male disease. However, more recent data showed a more homogenous sex prevalence. Unfortunately, in many studies in axial spondyloarthritis (axSpA), the number of women included is low and the analyses are often not stratified for gender distribution. The purpose of this review is to aggregate the existing data on gender differences in axSpA in order to increase the awareness that female axSpA patients are still under-recognized.

RECENT FINDINGS

Several studies considering gender differences revealed that female axSpA patients had different disease manifestations due to different immunological, hormonal, and genetic responses. For instance, allelic frequencies of the AHNK-gene and tissue non-specific alkaline phosphatase (TNAP) haplotypes differed between men and women with ankylosing spondylitis (AS). In addition, different levels of tumor necrosis factor (TNF), interleukins IL-6, IL-17, and IL-18, were found between the two sexes. Furthermore, female patients show a higher diagnostic delay compared to males. Several studies indicate a higher frequency of extra-articular manifestations (EAM) in female axSpA patients, such as enthesitis, psoriasis, and inflammatory bowel disease (IBD), whereas acute anterior uveitis is more prevalent in male patients. Male AS patients more frequently show a higher Bath Ankylosing Spondylitis Radiology Index (BASRI) scores and modified Stoke Ankylosing Spondylitis Spine Scores (mSASSS) than females, which indicates that males have higher radiological damage and radiographic progression. However, disease activity (BASDAI) and quality of life (AsQol) scores are significantly higher in women, and more importantly, they have significantly lower response rates to treatment with TNF inhibitors (TNFi) and a significantly lower drug adherence. Despite the fact that men with axial SpA have a worse radiologic prognosis, women have a high disease burden, in part because they have a longer delay in diagnosis, higher disease activity, and significantly less responsiveness to treatment with TNFi.

The Role of Flavonoids in Inhibiting Th17 Responses in Inflammatory Arthritis

Flavonoids have been considered powerful anti-inflammatory agents, and their exact immunomodulatory action as therapeutic agents in autoimmune diseases has started to emerge. Their role in the manipulation of immunoregulation is less understood. Several studies attempted to investigate the role of various flavonoids mainly in experimental models of autoimmune diseases, especially in the context of their potential effect on the increase of regulatory T cells (Tregs) and their ability to stimulate an overexpression of anti-inflammatory cytokines, in particular that of IL-10. The emergence of IL-17, a cytokine largely produced by Th17 cells, as a powerful proinflammatory stimulus which attenuates the induction of Tregs has prompted a series of studies investigating the role of flavonoids on Th17 cells in experimental models as well as human autoimmune diseases. This review thoroughly discusses accumulated data on the role of flavonoids on Th17 in rheumatoid arthritis and experimental autoimmune arthritis.