Biologic therapies and bone loss in rheumatoid arthritis

The clinical assessment of changes in bone density in rheumatoid arthritis patients': Role of DEXA scan and bone turnover biomarkers

In addition to generalised of bone loss and a higher fracture risk, rheumatoid arthritis (RA) causes periarticular bone erosions. Improvements in bone density/erosion and turnover may not go hand in hand with a positive clinical response to biological anti-inflammatory drugs assesed by disease activity score 28 (DAS28) in RA patients. This study aimed to understand how biologic anti-inflammatory drugs affect bone density, erosion, and turnover in RA patients. We examined bone mineral density (BMD) and bone turnover biomarkers. The study population consisted of 62 RA patients, 49 (79%) of whom were female and 13 (21%) of whom were male. The patients ranged in age from 40 to 79 years old. The patients' BMD was measured using a DEXA scan, and their plasma levels of bone turnover biomarkers CTX and osteocalcin were quantified utilizing an ELISA. BMD of the hip and lumbar spine in responder patients rose after therapy by 0.001g/cm2 (0.11 percent, p0.001 vs. before treatment) and 0.0396g/cm2 (3.96 percent, p0.001 vs. before treatment), respectively. Clinically non-responder patients' DAS28 revealed minor reductions in hip BMD values of -0.008g/cm2 (-0.78 percent, p0.001 vs. before therapy), as well as an improvement in lumbar spine BMD of 0.03g/cm2 (3.03 percent, p0.001 vs. before treatment). After 12 weeks of therapy, the CTX levels in responder patients dropped from 164 125 pg/ml to 131 129 pg/ml. Osteocalcin levels in non-responder patients increased substantially from 11.6 ng/ml to 14.9 ng/ml after 12 weeks of therapy compared to baseline (p = 0.01). Treatment with biologic anti-inflammatory medicines decreases widespread bone loss in RA patients' hip and lumbar spine. The beneficial effects of therapy on BMD were not associated with changes in disease activity of RA patients. Changes in plasma levels of bone turnover biomarkers such as sCTX and osteocalcin confirmed the treatment's beneficial effects.

The interplay of rheumatoid arthritis and osteoporosis: exploring the pathogenesis and pharmacological approaches

Rheumatoid arthritis (RA) and osteoporosis are two chronic disorders that are often seen together. RA is an autoimmune disorder that causes pain and inflammation in the joints, while osteoporosis is a disorder in which the bones become weak and fragile. Risk factors for bone loss in RA include disease activity, longer disease duration, erosive disease, autoantibody positivity, and joint damage leading to impaired physical activity. Recent research has shown that there is a complex interplay between immune cells, cytokines, and bone remodeling processes in both RA and osteoporosis. The bone remodeling process is regulated by cytokines and immune system signaling pathways, with osteoclasts activated through the RANK/RANKL/OPG pathway and the Wnt/DKK1/sclerostin pathway. Understanding these mechanisms can aid in developing targeted therapies for treatment of osteoporosis in RA patients. Current pharmacological approaches include anti-osteoporotic drugs such as bisphosphonates, denosumab, teriparatide, abaloparatide, raloxifene, and romosozumab. Conventional disease-modifying antirheumatic drugs such as methotrexate and biologicals including TNF inhibitors, IL-6 inhibitors, rituximab, and abatacept lower disease activity in RA and can improve bone metabolism by reducing inflammation but have limited impact on bone mineral density. This review will shed light on the relationship between osteoporosis and rheumatoid arthritis as well as the various factors that influence the onset of osteoporosis in RA patients. We also explore several treatment approaches to effectively managing osteoporosis in RA patients.

Correlation between Trabecular Bone Score and Homocysteine Level in Rheumatoid Arthritis Patients on Anti-TNF Inhibitors

Rheumatoid arthritis (RA) is an independent osteoporosis risk factor. Biologic and immunosuppressive treatment, and levels of homocysteine and 25-OH vitamin D may influence the trabecular bone score (TBS) in RA patients. We aimed to compare the effects of biological (b) and conventional synthetic (cs) disease-modifying anti-rheumatic drugs (DMARDs) on TBS in patients with RA and hyperhomocysteinemia (HHcy) or 25-OH vitamin D deficiency. Patients who had tests conducted for trabecular bone score, bone mineral density (BMD), homocysteine (Hcy) and 25-OH vitamin D at an interval of one year and met the inclusion criteria were enrolled in this retrospective study. Sixty-four patients with RA were enrolled and were divided into the following two groups: the first group (34 patients) had received treatment with bDMARDs and the second group (30 patients) had received csDMARDs. BDMARDs and csDMARDs had a positive influence on TBS and BMD. The best results were observed in the Adalimumab group (p = 0.033). Hyperhomocysteinemia and 25-OH vitamin D deficiency led to lower TBS values. Both bDMARDs and csDMARDs positively affected TBS and BMD in RA patients. High homocysteine serum levels or 25-OH vitamin D deficiency had a negative impact on TBS and BMD after 12 months. Our study aims to show the potential benefits of anti-TNF α drugs on TBS. This impact appears to be strongly associated with serum 25-OH vitamin D and homocysteine levels. Anti-TNF drugs may increase bone mineral density and microstructure. As a result, they may minimize the incidence of fractures in RA patients.

Recent advances in senescence-associated secretory phenotype and osteoporosis

The worldwide elderly population is on the rise, and aging is a major osteoporosis risk factor. Senescent cells accumulation can have a detrimental effect the body as we age. The senescence-associated secretory phenotype (SASP), an essential cellular senescence hallmark, is an important mechanism connecting cellular senescence to osteoporosis. This review describes in detail the characteristics of SASPs and their regulatory agencies, and shed fresh light on how SASPs from different senescent cells contribute to osteoporosis development. Furthermore, we summarized various innovative therapy techniques that target SASPs to lower the burden of osteoporosis in the elderly and discussed the potential challenges of SASPs-based therapy for osteoporosis as a new clinical trial.

Osteoimmunology: The Crosstalk between T Cells, B Cells, and Osteoclasts in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an ongoing inflammatory condition that affects the joints and can lead to severe damage to cartilage and bones, resulting in significant disability. This condition occurs when the immune system becomes overactive, causing osteoclasts, cells responsible for breaking down bone, to become more active than necessary, leading to bone breakdown. RA disrupts the equilibrium between osteoclasts and osteoblasts, resulting in serious complications such as localized bone erosion, weakened bones surrounding the joints, and even widespread osteoporosis. Antibodies against the receptor activator of nuclear factor-κB ligand (RANKL), a crucial stimulator of osteoclast differentiation, have shown great effectiveness both in laboratory settings and actual patient cases. Researchers are increasingly focusing on osteoclasts as significant contributors to bone erosion in RA. Given that RA involves an overactive immune system, T cells and B cells play a pivotal role by intensifying the immune response. The imbalance between Th17 cells and Treg cells, premature aging of T cells, and excessive production of antibodies by B cells not only exacerbate inflammation but also accelerate bone destruction. Understanding the connection between the immune system and osteoclasts is crucial for comprehending the impact of RA on bone health. By delving into the immune mechanisms that lead to joint damage, exploring the interactions between the immune system and osteoclasts, and investigating new biomarkers for RA, we can significantly improve early diagnosis, treatment, and prognosis of this condition.

Rheumatoid arthritis, disease-modifying antirheumatic drugs and risk of major osteoporotic fracture: prospective data from the HUNT Study, Norway

OBJECTIVES

Rheumatoid arthritis has been associated with increased fracture risk. New treatments have improved the course of the disease substantially, but it is not clear if this influences fracture risk. We examined if rheumatoid arthritis, overall and according to disease-modifying antirheumatic drugs (DMARDs), is associated with a risk of major osteoporotic fractures.

METHODS

Overall, 92 285 participants in the population-based Nord-Trndelag Health Study (HUNT), Norway were included and linked with hospital records for a validated rheumatoid arthritis diagnosis (n=605), type of DMARD treatment and fracture diagnosis. Participants were followed up until the first major osteoporotic fracture, death, emigration or end of follow-up. Cox regression was used to estimate HRs for fractures among individuals with rheumatoid arthritis, overall and by DMARD treatment, compared with participants without rheumatoid arthritis.

RESULTS

A total of 9670 fractures were observed during follow-up, of which 88 were among those with rheumatoid arthritis. Compared with the reference group of participants without rheumatoid arthritis, those with the disease had an HR of fracture of 1.41 (95% CI 1.13 to 1.74). The association was largely similar for users of csDMARDs (HR 1.44; 95% CI 1.15 to 1.81), whereas the association for bDMARD users was weaker and less precise (HR 1.19; 95% CI 0.64 to 2.21).

CONCLUSION

Participants with rheumatoid arthritis had a 40% higher risk of fracture than participants without the disease. A similar fracture risk was observed for conventional synthetic DMARD use, whereas there was weak evidence that the use of biological DMARDs may be associated with a somewhat lower fracture risk.

Neutrophil extracellular traps mediate bone erosion in rheumatoid arthritis by enhancing RANKL-induced osteoclastogenesis

BACKGROUND AND PURPOSE

Rheumatoid arthritis (RA) is a chronic autoimmune disease that can cause bone erosion due to increased osteoclastogenesis. Neutrophils involvement in osteoclastogenesis remains uncertain. Given that neutrophil extracellular traps (NETs) can act as inflammatory mediators in rheumatoid arthritis, we investigated the role of NETs in stimulating bone loss by potentiating osteoclastogenesis during arthritis.

EXPERIMENTAL APPROACH

The level of NETs in synovial fluid from arthritis patients was assessed. Bone loss was evaluated by histology and micro-CT in antigen-induced arthritis (AIA)-induced WT mice treated with DNase or in Padi4-deficient mice (Padi4flox/flox LysMCRE ). The size and function of osteoclasts and the levels of RANKL and osteoprotegerin (OPG) released by osteoblasts that were incubated with NETs were measured. The expression of osteoclastogenic marker genes and protein levels were evaluated by qPCR and western blotting. To assess the participation of TLR4 and TLR9 in osteoclastogenesis, cells from Tlr4-/- and Tlr9-/- mice were cultured with NETs.

KEY RESULTS

Rheumatoid arthritis patients had higher levels of NETs in synovial fluid than osteoarthritis patients, which correlated with increased levels of RANKL/OPG. Moreover, patients with bone erosion had higher levels of NETs. Inhibiting NETs with DNase or Padi4 deletion alleviated bone loss in arthritic mice. Consistently, NETs enhanced RANKL-induced osteoclastogenesis that was dependent on TLR4 and TLR9 and increased osteoclast resorptive functions in vitro. In addition, NETs stimulated the release of RANKL and inhibited osteoprotegerin in osteoblasts, favouring osteoclastogenesis.

CONCLUSIONS AND IMPLICATIONS

Inhibiting NETs could be an alternative strategy to reduce bone erosion in arthritis patients.

Risk of fracture in women with glucocorticoid requiring diseases is independent from glucocorticoid use: An analysis on a nation-wide database

OBJECTIVE

Glucocorticoid-induced osteoporosis (GIOP) is a common cause of secondary osteoporosis. However, glucocorticoid requiring diseases pose a risk themselves for fracture. The aim of the present study was to determine the risk of fracture associated with variety of glucocorticoid requiring diseases independently from glucocorticoid use and other risk factors for osteoporosis.

METHODS

We conducted a retrospective cross-sectional analysis of a nation-wide cohort (DeFRACalc79 database). We used multivariable regression analysis adjusting for several risk factors for fracture and glucocorticoid intake to estimate the independent role of glucocorticoid requiring illnesses on fracture risk.

RESULTS

We found that patients with rheumatoid arthritis, connective tissue diseases, chronic obstructive pulmonary disease (COPD) and neurological diseases were at greater risk of vertebral or hip fracture (crude ORs 1.31, 1.20, 1.92 and 2.97 respectively). After adjusting for potential confounders COPD and neurological diseases remained significantly associated with an increased risk of vertebral or hip fractures (aORs 1.33, 95 % CI 1.18-1.49 and 2.43, 95 % CI 2.17-2.74). Rheumatoid arthritis, COPD, IBD and neurological diseases also significantly increased the risk of non-vertebral, non-hip fractures (aORs 1.23, 1.42, 1.52 and 1.94 respectively).

CONCLUSION

Some glucocorticoid requiring diseases were independently associated with an increased risk of fractures. COPD and neurological diseases with both vertebral and non-vertebral fracture risk while RA and IBD were independently associated only with non-vertebral, non-hip fractures.

Advances in surgical treatment for atlantoaxial instability focusing on rheumatoid arthritis: Analysis of a series of 67 patients

AIM

An estimated 88% of rheumatoid arthritis (RA) patients experience various degrees of cervical spine involvement. The excessive movement of the atlantoaxial joint, which connects the occiput to the upper cervical spine, results in atlantoaxial instability (AAI). AAI stabilization is usually achieved by C1 lateral mass-to-C2 pedicle screw-rod fixation (LC1-PC2 fixation), which is technically challenging in RA patients who often show destructive changes in anatomical structures. This study aimed to analyze the clinical results and operative experiences of C1-C2 surgery, with emphasis on the advancement of image-guided surgery and augmented reality (AR) assisted navigation.

METHODS

We presented our two decades of experience in the surgical management of AAI from April 2004 to November 2022.

RESULTS

We have performed surgery on 67 patients with AAI, including 21 traumatic odontoid fractures, 20 degenerative osteoarthritis, 11 inflammatory diseases of RA, 5 congenital anomalies of the os odontoideum, 2 unknown etiologies, 2 movement disorders, 2 previous implant failures, 2 osteomyelitis, 1 ankylosing spondylitis, and 1 tumor. Beginning in 2007, we performed LC1-PC2 fixation under C-arm fluoroscopy. As part of the progress in spinal surgery, since 2011 we used surgical navigation from presurgical planning to intraoperative navigation, using the preoperative computed tomography (CT) -based image-guided BrainLab navigation system. In 2021, we began using intraoperative CT scan and microscope-based AR navigation.

CONCLUSION

The technical complexities of C1-C2 surgery can be mitigated by CT-based image-guided surgery and microscope-based AR navigation, to improve accuracy in screw placement and overall clinical outcomes, particularly in RA patients with AAI.

Magnetic nanocomplexes coupled with an external magnetic field modulate macrophage phenotype - a non-invasive strategy for bone regeneration

Chronic inflammation is a major cause for the pathogenesis of musculoskeletal diseases such as fragility fracture, and nonunion. Studies have shown that modulating the immune phenotype of macrophages from proinflammatory to prohealing mode can heal recalcitrant bone defects. Current therapeutic strategies predominantly apply biochemical cues, which often lack target specificity and controlling their release kinetics in vivo is challenging spatially and temporally. We show a magnetic iron-oxide nanocomplexes (MNC)-based strategy to resolve chronic inflammation in the context of promoting fracture healing. MNC internalized pro-inflammatory macrophages, when coupled with an external magnetic field, exert an intracellular magnetic force on the cytoskeleton, which promotes a prohealing phenotype switch. Mechanistically, the intracellular magnetic force perturbs actin polymerization, thereby significantly reducing nuclear to cytoplasm redistribution of MRTF-A and HDAC3, major drivers of inflammatory and osteogenic gene expressions. This significantly reduces Nos2 gene expression and subsequently downregulates the inflammatory response, as confirmed by quantitative PCR analysis. These findings are a proof of concept to develop MNC-based resolution-centric therapeutic intervention to direct macrophage phenotype and function towards healing and can be translated either to supplement or replace the currently used anti-inflammatory therapies for fracture healing.

Long-term fracture risk in rheumatoid arthritis: impact of early sustained DAS28-remission and restored function, progressive erosive disease, body mass index, autoantibody positivity and glucocorticoids. A cohort study over 10 years

BACKGROUND

Risk of fragility fractures in patients with rheumatoid arthritis (RA) is increased. Disease-related inflammation in RA is associated with low Bone Mineral Density (BMD). However, effects of specific disease factors on fracture occurrence and whether or not such disease effects are independent of BMD are unknown.

METHODS

Analysis of fracture outcome in the prospective cohort of 2557 patients with early RA (67% women, mean age 58.1 ± 15.6 years) during an observation period of 10.6 ± 4.7 years. In 602 patients BMD was measured at baseline. The first major fragility fractures were considered. Kaplan-Meier and Cox regression analysis, adjusted for traditional factors, prior fracture, disease activity and period of inclusion, were used to estimate the risk of the outcome.

RESULTS

During follow-up fracture occurred in 352 patients (13.8%), a rate of 13/1000 p-y. A proportional risk reduction for the outcome was associated with Body Mass Index (BMI) at baseline, BMI ≥ 30 kg/m2, and over the first two years sustained Disease Activity Score (DAS28)-remission, DAS28-low disease activity and Health Assessment Questionnaire (HAQ) ≤ 0.5. The proportional risk elevation for fractures was associated with BMI ≤ 20 kg/m2, DAS28 at baseline, 6-month and at 1-year, cumulative DAS28 over the two years, RF, erosion score progression at 2-year, HAQ score and HAQ ≥ 1 at 6-month and 1-year and showed a trend for ACPA positivity. The estimated fracture risk was increased in users of glucocorticoids (GC), associated with a higher GC-dosage at follow-ups and a higher cumulative dosage over two years, independently of disease activity. With adjustment for BMD, there was no difference in fracture outcome by exposure to GC. The effects of a higher BMI, DAS28-remission and low HAQ ≤ 0.5 attained at 6-month of treatment initiation and sustained up to 2 years, RF, ACPA, and erosion score progression at 2-year were independent of low BMD.

CONCLUSIONS

This analysis supports importance of RA-specific risk factors in early RA for future major fragility fractures. Treat-to-target strategy and restored functional capacity in early RA-disease are important to prevent fractures. Autoantibody positivity, progressively erosive disease, and low weight could have additional value for personalized fracture preventive strategies in early RA.

Guizhi Shaoyao Zhimu granules attenuate bone destruction in mice with collagen-induced arthritis by promoting mitophagy of osteoclast precursors to inhibit osteoclastogenesis

BACKGROUND

Guizhi Shaoyao Zhimu decoction, a traditional Chinese medicine formula used empirically for the treatment of rheumatoid arthritis (RA), has been shown to alleviate bone destruction in rats with collagen-induced arthritis (CIA).

PURPOSE

The aim of this study is to characterize the effects of Guizhi Shaoyao Zhimu granules (GSZGs) on bone destruction in RA and the underlying mechanism.

STUDY DESIGN

A CIA arthritis model using DBA/1 mice. The animals were divided into a normal group; CIA model group; low, medium, and high-dose GSZG groups (3, 6, and 9 g/kg/day); and a methotrexate group (1.14 mg/kg/w). In vitro, a cytokine induced osteoclastogenesis model was established.

METHODS

After 28 days of treatment, the paw volume was measured, bone destruction was examined by micro-CT, and the generation of osteoclasts in bone tissue was evaluated via tartrate-resistant acid phosphatase (TRAP) staining. Furthermore, the inhibitory effect and underlying mechanism of action of GSZG on RANKL-induced osteoclastogenesis were investigated in vitro.

RESULTS

The in vivo analyses demonstrated that the paw volume and degree of bone erosion of mice in the medium- and high-dose GSZG groups were significantly decreased compared to the CIA model group. In addition, GSZG treatment suppressed the excessive generation of osteoclasts in the bone tissue of CIA mice. In vitro, GSZG inhibited RANKL-induced osteoclastogenesis and osteoclast-mediated bone resorption. Specifically, it only inhibited the generation of osteoclast precursors (OCPs); it had no significant effect on the fusion of OCPs or maturation of osteoclasts. Finally, we showed that the inhibitory effect of GSZG on osteoclastogenesis was related to the promotion of PTEN-induced kinase protein 1 (PINK1)/Parkin pathway-mediated mitophagy of osteoclast precursors, which was verified using a PINK1 knockdown small interfering RNA in OCPs.

CONCLUSION

These findings indicate that GSZG is a candidate for the treatment of bone destruction in RA and provide a more detailed elucidation of the mechanism of GSZG anti-RA bone erosion, i.e., inhibition of the ROS/NF-κB axis through the PINK1/Parkin-mediated mitochondrial autophagic pathway to inhibit osteoclast precursor production, compared to the published literature.

Chronic arthritides and bone structure: focus on rheumatoid arthritis-an update

Normal bone remodeling depends of a balance between bone forming cells, osteoblasts and bone resorbing cells, the osteoclasts. In chronic arthritides and some inflammatory and autoimmune diseases such as rheumatoid arthritis, there is a great constellation of cytokines produced by pannus that impair bone formation and stimulate bone resorption by inducing osteoclast differentiation and inhibiting osteoblast maturation. Patients with chronic inflammation have multiple causes that lead to low bone mineral density, osteoporosis and a high risk of fracture including circulating cytokines, impaired mobility, chronic administration of glucocorticoids, low vitamin D levels and post-menopausal status in women, among others. Biologic agents and other therapeutic measures to reach prompt remission might ameliorate these deleterious effects. In many cases, bone acting agents need to be added to conventional treatment to reduce the risk of fractures and to preserve articular integrity and independency for daily living activities. A limited number of studies related to fractures in chronic arthritides were published, and future investigation is needed to determine the risk of fractures and the protective effects of different treatments to reduce this risk.

MiR-30e-5p deficiency exerts an inhibitory effect on inflammation in rheumatoid arthritis via regulating Atl2 expression

OBJECTIVES

This study aims to investigate the inflammatory effect of the microRNA (miRNA) miR-30e-5p on rheumatoid arthritis (RA) development in RA mice and fibroblast-like synoviocytes (FLS).

MATERIALS AND METHODS

MiR-30e-5p and atlastin GTPase 2 (Atl2) expression in RA tissues and RA-FLS was evaluated using real-time quantitative polymerase chain reaction. The function of miR-30e-5p in inflammation of RA mice and RA-FLS was analyzed by enzyme-linked immunosorbent assay (ELISA) and Western blotting. 5-ethynyl-2'-deoxyuridine (EdU) assay was used to detect RA-FLS proliferation. Luciferase reporter assay was to confirm the interaction between miR-30e-5p and Atl2.

RESULTS

MiR-30e-5p expression was upregulated in the tissues from RA mice. Silencing miR-30e-5p alleviated inflammation in RA mice and RA-FLS. MiR-30e-5p negatively modulated Atl2 expression. Atl2 knockdown exerted a proinflammatory effect on RA-FLS. Atl2 knockdown rescued the inhibitory effect of miR-30e-5p knockdown on proliferation and inflammatory response of RA-FLS.

CONCLUSION

MiR-30e-5p knockdown inhibited the inflammatory response in RA mice and RA-FLS through Atl2.

Association between disease-modifying antirheumatic drugs and bone turnover biomarkers

Rheumatoid arthritis (RA) has been linked to an increased risk of osteoporosis as well as fractures. Patients diagnosed with RA had a 25% increased risk of osteoporotic fracture, according to a recent population-based cohort study that compared them to people without RA. Several studies have found a correlation between osteoporosis and the presence of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1, and 6. These cytokines play a crucial part in the process of bone resorption by boosting osteoclast activation and encouraging osteoclast differentiation. Based on the correlation between RA, osteoporosis, and inflammation, it is possible that systemic immunosuppression with disease-modifying antirheumatic drugs (DMARDs) can help individuals with RA have a lower chance of developing osteoporosis and osteoporotic fractures. There is little information on how different DMARDs, biologic or non-biologic, affect RA patients' bone metabolism. In this study, we present an overview of the influence that targeted therapies, such as biologics, non-biologics, and small molecule inhibitors, have on bone homeostasis in RA patients.

Changes in Bone Metabolism in Patients with Rheumatoid Arthritis during Tumor Necrosis Factor Inhibitor Therapy

Tumor necrosis factor alpha (TNF-α), which enhances osteoclast activity and bone resorption, is one of the key inflammation mediators in rheumatoid arthritis (RA). The aim of this study was to assess the influence of yearlong TNF-α inhibitor application on bone metabolism. The study sample comprised 50 female patients with RA. Analyses involved the osteodensitometry measurements obtained using a "Lunar" type apparatus and the following biochemical markers from serum: procollagen type 1 N-terminal propeptide (P1NP), beta crosslaps C-terminal telopeptide of collagen type I (b-CTX) by ECLIA method, total and ionized calcium, phosphorus, alkaline phosphatase, parathyroid hormone and vitamin D. Analyses revealed changes in bone mineral density (BMD) at L1-L4 and the femoral neck, with the difference in mean BMD (g/cm²) not exceeding the threshold of statistical significance (p = 0.180; p = 0.502). Upon completion of 12-month therapy, a significant increase (p < 0.001) in P1NP was observed relative to b-CTX, with mean total calcium and phosphorus values following a decreasing trend, while vitamin D levels increased. These results suggest that yearlong application of TNF inhibitors has the capacity to positively impact bone metabolism, as indicated by an increase in bone-forming markers and relatively stable BMD (g/cm²).

Novel Bruton's tyrosine kinase inhibitor TAS5315 suppresses the progression of inflammation and joint destruction in rodent collagen-induced arthritis

Rheumatoid arthritis is an inflammatory autoimmune disease, characterized by autoantibody production, synovial inflammation, and joint destruction. Its pathogenesis is due to environmental factors and genetic backgrounds. Bruton's tyrosine kinase is a cytoplasmic non-receptor tyrosine kinase, expressed in most hematopoietic cell lineages, except T cells and plasma cells, and regulates various immune-related signaling pathways, thereby playing a crucial role in pathogenesis. Thus, inhibiting Bruton's tyrosine kinase may prove beneficial in treating autoimmune diseases. In the present study, we characterized Bruton's tyrosine kinase inhibitor, TAS5315, in vitro and evaluated its therapeutic effects in experimental arthritis models. TAS5315 markedly inhibited Bruton's tyrosine kinase enzyme activity and suppressed the B-cell receptor signaling pathway in Ramos cells. Moreover, it suppressed the expression of CD69, CD86, and MHC class II in mouse B lymphocytes and the production of TNF-α and MIP-1α in mouse macrophages and decreased bone resorption activity in mouse osteoclasts. Furthermore, it ameliorated the pathological changes in two rodent models of collagen-induced arthritis in vivo. TAS5315 improved bone mineral density and bone intensity. Thus, these results suggest that TAS5315 could be a promising therapeutic option for the treatment of rheumatoid arthritis.

The Local Release of Teriparatide Incorporated in 45S5 Bioglass Promotes a Beneficial Effect on Osteogenic Cells and Bone Repair in Calvarial Defects in Ovariectomized Rats

With the increase in the population's life expectancy, there has also been an increase in the rate of osteoporosis, which has expanded the search for strategies to regenerate bone tissue. The ultrasonic sonochemical technique was chosen for the functionalization of the 45S5 bioglass. The samples after the sonochemical process were divided into (a) functionalized bioglass (BG) and (b) functionalized bioglass with 10% teriparatide (BGT). Isolated mesenchymal cells (hMSC) from femurs of ovariectomized rats were differentiated into osteoblasts and submitted to in vitro tests. Bilateral ovariectomy (OVX) and sham ovariectomy (Sham) surgeries were performed in fifty-five female Wistar rats. After a period of 60 days, critical bone defects of 5.0 mm were created in the calvaria of these animals. For biomechanical evaluation, critical bone defects of 3.0 mm were performed in the tibias of some of these rats. The groups were divided into the clot (control) group, the BG group, and the BGT group. After the sonochemical process, the samples showed modified chemical topographic and morphological characteristics, indicating that the surface was chemically altered by the functionalization of the particles. The cell environment was conducive to cell adhesion and differentiation, and the BG and BGT groups did not show cytotoxicity. In addition, the experimental groups exhibited characteristics of new bone formation with the presence of bone tissue in both periods, with the BGT group and the OVX group statistically differing from the other groups (p < 0.05) in both periods. Local treatment with the drug teriparatide in ovariectomized animals promoted positive effects on bone tissue, and longitudinal studies should be carried out to provide additional information on the biological performance of the mutual action between the bioglass and the release of the drug teriparatide.

Frequency of osteoporosis in Chinese patients with rheumatoid arthritis: a meta-analysis

OBJECTIVE

To evaluate the current frequency of osteoporosis (OP) in Chinese patients with rheumatoid arthritis (RA) through meta-analysis.

METHODS

The databases of PubMed, Web of Science, Cochrane Library, CNKI, Wan Fang, CBM, and VIP were searched for relevant literature regarding the occurrence of OP in Chinese patients with RA from January 1, 2000, to September 15, 2022. The literature was screened using inclusion and exclusion criteria, and qualifying articles were subjected to data extraction, quality evaluation, and meta-analysis using Stata 17.0 software.

RESULTS

Altogether, 44 publications were included in this study, with a total sample size of 12,264 RA cases and 4532 patients with OP. Meta-analysis revealed that the frequency of OP in patients with RA was 37.67% [95% CI: 34.38%, 40.97%], while subgroup analysis showed that the frequency in South China was 49.43% [95% CI: 40.53%, 58.32%]. Also, the frequency in men was 29.29% [95% CI: 22.42%, 36.16%], which was significantly lower than in women (41.89% [95% CI: 36.87%, 46.90%]). The incidence rate in pre-menopausal women was only 15.19% [95% CI: 8.79%, 21.59%], much lower than the figure of 54.29% [95% CI: 45.28%, 63.30%] for post-menopausal women. Additionally, the frequency rates in the low, intermediate, and high disease activity groups were 24.52% [95% CI: 11.52%, 37.52%)], 27.67% [95% CI: 13.50%, 41.85%], and 57.96% [95% CI: 37.35%, 78.56%], respectively.

CONCLUSION

The frequency of OP in the Chinese RA population is higher than the world average, and patients with RA should receive standardized anti-RA therapy at an early stage, with emphasis on bone health in postmenopausal women, patients with high disease activity or longer disease duration.

Positive Effects of Biologics on Osteoporosis in Rheumatoid Arthritis

Osteoporosis is a systemic skeletal disorder that causes vulnerability of bones to fracture owing to reduction in bone density and deterioration of the bone tissue microstructure. The prevalence of osteoporosis is higher in patients with autoimmune inflammatory rheumatic diseases, including rheumatoid arthritis (RA), than in those of the general population. In this autoimmune inflammatory rheumatic disease, in addition to known risk factors for osteoporosis, various factors such as chronic inflammation, autoantibodies, metabolic disorders, drugs, and decreased physical activity contribute to additional risk. In RA, disease-related inflammation plays an important role in local or systemic bone loss, and active treatment for inflammation can help prevent osteoporosis. In addition to conventional synthetic disease-modifying anti-rheumatic drugs that have been traditionally used for treatment of RA, biologic DMARDs and targeted synthetic DMARDs have been widely used. These agents can be employed more selectively and precisely based on disease pathogenesis. It has been reported that these drugs can inhibit bone loss by not only reducing inflammation in RA, but also by inhibiting bone resorption and promoting bone formation. In this review, the pathogenesis and research results of the increase in osteoporosis in RA are reviewed, and the effects of biological agents on osteoporosis are discussed.

Hadh deficiency induced oligoasthenoteratozoospermia through the TNF-α/Bcl-2 pathway in male mice

The process of spermatogenesis is a complex and delicate process that is still not fully understood. In this study, we examined the role of fatty acid oxidase 3-hydroxy acyl CoA dehydrogenase (HADH) in maintaining normal spermatogenesis in mice. In male mice, ablation of the Hadh gene using CRISPR/Cas9 technology arrested spermatocyte meiosis, increased multinucleated giant germ cells and vacuoles in seminiferous tubules, and accompanied with acrosomal dysplasia. Hadh^-/- male mice showed the typical features of oligoasthenoteratozoospermia (OAT), including decreased sperm concentration and motility and increased sperm abnormalities. Next, we explored the molecular events in the testes of the mutant mice. We found fatty acids accumulated in the testis of Hadh^-/- mice. And also, inflammatory factors TNF-α, IL-1β, and IL-6 were significantly increased, apoptosis-related protein Bcl-2 was decreased, and Bax and cleaved-Caspase3 were increased in Hadh^-/- male mice testis. After using etanercept, a specific inhibitor of TNF-α, testis injury caused by Hadh knockout was significantly alleviated, the sperm quality and motility were improved, and germ cell apoptosis was reduced. So our study demonstrated that Hadh deletion caused an increase in fatty acids. The accumulated fatty acids further induced testicular inflammation and germ cell apoptosis through the TNF-α/Bcl-2 signaling pathway, finally resulting in OAT in the Hadh^-/- mice. Inhibiting TNF-α may be used as a new treatment approach for testicular inflammation and OAT.

The effect of disease-modifying antirheumatic drugs (DMARDs) on bone homeostasis in rheumatoid arthritis (RA) patients

The autoimmune disease known as rheumatoid arthritis (RA) has been linked to the deterioration of bone. Bone erosion is a hallmark of RA and is linked to the severity of the disease as well as a poor functional result. Erosion of periarticular cortical bone is a common feature seen on plain radiographs of patients with RA. This characteristic feature is the result of excessive bone resorption and inadequate formation of bone. It has been determined that there is a complex interaction between the inflammatory condition seen in RA and bone destruction. Increased knowledge of the pathways and other mechanisms involved in osteoclastogenesis has resulted from advances in both animal and clinical investigations. Also, Biological and targeted medicines have modified RA's bone metabolism. Here, we provide a narrative overview of the literature on the pathomechanisms of bone structure involved in biological and targeted treatments for RA and also, the clinical implications of disease-modifying antirheumatic drugs (DMARDs) are discussed. In light of the fact that these newer treatments present patients with RA with new possibilities for disease improvement and symptom control, it is imperative that additional rigorous evidence be gathered to provide a clinical reference for both patients and their treating physicians.

Metabolic Abnormalities, Cardiovascular Disease, and Metabolic Syndrome in Adult Rheumatoid Arthritis Patients: Current Perspectives and Clinical Implications

AIM

Rheumatoid arthritis is a prevalent worldwide disease, associated with an increased risk of multiple metabolic abnormalities that generate a higher disease burden.

OBJECTIVE

To gather the available evidence on the epidemiology, pathophysiology, current perspectives, clinical implications and prognosis of metabolic abnormalities in patients with rheumatoid arthritis.

METHODS

This is a narrative literature review. Search was conducted in PubMed, OVID, and Taylor & Francis databases, using the following MeSH terms: "Arthritis Rheumatoid", "Metabolic Diseases", and "Metabolic Syndrome".

RESULTS

This study describes the main metabolic manifestations of rheumatoid arthritis. Research has recognized that rheumatoid arthritis and metabolic abnormalities share pathophysiological mechanisms with an additive effect that increases cardiovascular risk. In that context, appropriate antirheumatic treatment can also impact on cardiovascular risk.

CONCLUSION

There are metabolic abnormalities in rheumatoid arthritis patients that increase cardiovascular risk. Therefore, it is crucial to evaluate cardiovascular risk to provide appropriate comprehensive management to reduce morbidity and mortality in patients with this disease.

The Effect of Anti-rheumatic Drugs on the Skeleton

The therapeutic armamentarium for rheumatoid arthritis has increased substantially over the last 20 years. Historically antirheumatic treatment was started late in the disease course and frequently included prolonged high-dose glucocorticoid treatment which was associated with accelerated generalised bone loss and increased vertebral and non-vertebral fracture risk. Newer biologic and targeted synthetic treatments and a combination of conventional synthetic DMARDs prevent accelerated systemic bone loss and may even allow repair of cortical bone erosions. Emerging data also gives new insight on the impact of long-term conventional synthetic DMARDs on bone health and fracture risk and highlights the need for ongoing studies for better understanding of "established therapeutics". An interesting new antirheumatic treatment effect is the potential of erosion repair with the use of biologic DMARDs and janus kinase inhibitors. Although several newer anti-rheumatic drugs seem to have favorable effects on bone mineral density in RA patients, these effects are modest and do not seem to influence the fracture risk thus far. We summarize recent developments and findings of the impact of anti-rheumatic treatments on localized and systemic bone integrity and health.

Pathomechanisms of bone loss in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease, in which the inflammatory processes involve the skeletal system and there is marked destruction of the bones and the surrounding structures. In this review, we discuss the current concepts of osteoimmunology in RA, which represent the molecular crosstalk between the immune and skeletal systems, resulting in the disruption of bone remodeling. Bone loss in RA can be focal or generalized, leading to secondary osteoporosis. We have summarized the recent studies of bone loss in RA, which focused on the molecular aspects, such as cytokines, autoantibodies, receptor activator of nuclear kappa-β ligand (RANKL) and osteoprotegerin (OPG). Apart from the above molecules, the role of aryl hydrocarbon receptor (Ahr), which is a potential key mediator in this process through the generation of the Th17 cells, is discussed. Hence, this review highlights the key insights into molecular mechanisms of bone loss in RA.

Mechanisms of Systemic Osteoporosis in Rheumatoid Arthritis

Rheumatoid arthritis (RA), an autoimmune disease, is characterized by the presence of symmetric polyarthritis predominantly of the small joints that leads to severe cartilage and bone destruction. Based on animal and human data, the pathophysiology of osteoporosis, a frequent comorbidity in conjunction with RA, was delineated. Autoimmune inflammatory processes, which lead to a systemic upregulation of inflammatory and osteoclastogenic cytokines, the production of autoantibodies, and Th cell senescence with a presumed disability to control the systemic immune system's and osteoclastogenic status, may play important roles in the pathophysiology of osteoporosis in RA. Consequently, osteoclast activity increases, osteoblast function decreases and bone metabolic and mechanical properties deteriorate. Although a number of disease-modifying drugs to treat joint inflammation are available, data on the ability of these drugs to prevent fragility fractures are limited. Thus, specific treatment of osteoporosis should be considered in patients with RA and an associated increased risk of fragility fractures.

Correlation between vitamin D metabolites and rheumatoid arthritis with osteoporosis by ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS)

INTRODUCTION

Our aim is to study the correlation between vitamin D metabolites and osteoporosis in rheumatoid arthritis (RA) by ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). At the same time, other influencing factors and serum biomarkers of osteoporosis in patients with RA were studied.

MATERIALS AND METHODS

Patients with RA admitted from January 2020 to December 2020 were selected at our hospital. The subjects were divided into the normal bone mineral density (BMD), osteopenia, and osteoporosis groups. The differences of vitamin D (VD) metabolites among groups were compared. The Pearson correlation coefficient was used to analyze the relationship between BMD and various parameters. The relationship between BMD and influencing factors was studied by a multiple linear regression equation.

RESULTS

A total of 287 patients with RA were included. RA patients with 25-hydroxy vitamin D [25(OH)D] deficiency accounted for 43.63% and 25(OH)D insufficient levels accounted for 31.37%. There were 31 cases (10.80%) in the normal BMD group, 161 cases (56.10%) in the osteopenia group, and 95 cases (33.10%) in the osteoporosis group. The BMD of L1-4 (T- score) was negatively correlated with age (P < 0.05), course of disease (P < 0.05), and erythrocyte sedimentation rate (ESR) (P < 0.05), and positively correlated with 25(OH)D₃ (P < 0.05). The multiple linear regression model results showed that age and 25(OH)D₃ were independent predictors of BMD; this explained 22.11% of the total variation.

CONCLUSIONS

VD deficiency and insufficient are common in RA patients. RA patients can be appropriately supplemented with VD. VD3 may be a better choice.

Biological Disease-Modifying Antirheumatic Drugs and Osteoporotic Fracture Risk in Patients with Rheumatoid Arthritis: A Danish Cohort Study

OBJECTIVES

Clinical trials have shown a beneficial effect from biological disease-modifying antirheumatic drugs (bDMARDs) on hand or axial bone loss in patients with rheumatoid arthritis; however, it is unclear if this translates to a reduced fracture risk. We investigated the effect of bDMARDs on osteoporotic fracture risk compared to no biological treatment in rheumatoid arthritis.

METHODS

A cohort of patients with rheumatoid arthritis aged 18+ from DANBIO was linked to population-based health registries in Denmark (2006-2016). Adopting a prevalent new-user design, we matched bDMARD users to bDMARD-naïve patients using time-conditional propensity scores. The risk of incident osteoporotic fractures (including hip, vertebrae, humerus, and forearm) was estimated among the matched patients by Cox proportional hazards models.

RESULTS

Out of 24,678 patients with rheumatoid arthritis, 4265 bDMARD users were matched to the same number of bDMARD-naïve patients (mean age 56.2 years, 74% female). During follow-up, 229 osteoporotic fractures occurred among bDMARD users and 205 fractures among bDMARD-naïve patients (incidence rates 12.1 and 13.0 per 1000 person-years, respectively). The use of bDMARDs was not associated with a reduced risk of osteoporotic fractures among patients with rheumatoid arthritis (hazard ratio 0.97, 95% confidence interval 0.78-1.20), compared with no biological treatment. The risk estimates were similar for all osteoporotic fracture sites.

CONCLUSION

We found no independent beneficial effect from using bDMARDs on reducing the risk of osteoporotic fractures in patients with rheumatoid arthritis.

Comparison of Romosozumab Versus Denosumab Treatment on Bone Mineral Density After One Year in Rheumatoid Arthritis Patients with Severe Osteoporosis: A Randomized Clinical Pilot Study

OBJECTIVES

To investigate the effect of romosozumab versus denosumab treatment on bone mineral density (BMD), disease activity, and joint damage in patients with rheumatoid arthritis (RA) and severe osteoporosis.

METHODS

Fifty-one postmenopausal women were enrolled and randomized equally into two groups to receive either romosozumab or the denosumab. Changes (Δ) in the BMD (at lumbar spine, total hip, and femoral neck), disease activity score in 28 joints (DAS28)-erythrocyte sedimentation rate (ESR), and van der Heijde-modified Total Sharp Score (TSS) from baseline to 12 months after treatment were evaluated.

RESULTS

The ΔBMD at 12 months in the romosozumab and denosumab groups were 10.2 ± 5.6% and 5.0 ± 3.1% (p = 0.002) for the lumbar spine, 3.7 ± 4.9% and 3.5 ± 3.0% (p = 0.902) for total hip, and 3.6 ± 4.7% and 3.2 ± 4.9% (p = 0.817) for femoral neck, respectively. The ΔDAS28-ESR at 12 months in the romosozumab and denosumab groups was 0.14 and 0.22 (p = 0.643), respectively, whereas, the ΔTSS at 12 months was 0.33 and 0.29 (p = 0.927), respectively.

CONCLUSIONS

Our results suggest that romosozumab treatment was more effective in increasing the BMD at the lumbar spine than denosumab, and may be selected for patients who require a significant increase in the lumbar spine BMD. Moreover, romosozumab may be not affect disease activity and joint damage in patients with RA.

Osteoporosis in Rheumatic Diseases

The risk of osteoporosis and fragility fracture is increased in patients with autoimmune rheumatic diseases. Although the use of glucocorticoids is the major contributing factor, inflammation mediated by cytokines and growth factors and other medications, including the biologic and targeted disease-modifying antirheumatic drugs, also play important roles in bone remodeling. Pro-inflammatory cytokines such as IL-1, IL-6, IL-17, and TNF[Formula: see text] increase RANK expression and promote osteoclast activity while inhibiting osteoblast-mediated bone formation through the Dickkopf-1 pathway. Certain autoantibodies stimulate differentiation of the osteoclasts, resulting in localized bone resorption. This article covers the prevalence and risk factors for osteoporosis in patients with common rheumatic diseases and the role of inflammatory cytokines and other clinical factors. Controlling disease-related inflammation and optimizing the diagnostic and therapeutic instrumentation is needed to reduce fragility fractures in patients with rheumatic diseases.

Modulation of Dopamine Receptors on Osteoblasts as a Possible Therapeutic Strategy for Inducing Bone Formation in Arthritis

Rheumatoid arthritis (RA) is associated with systemic osteoporosis, which leads to severe disability and low quality of life. Current therapies target osteoclasts to reduce bone degradation, but more treatment options would be required to promote bone protection by acting directly on osteoblasts (OB). Recently, the local production of dopamine in inflamed joints of RA has been observed. Thus, in this project, we aimed to determine the implication of the neurotransmitter dopamine in the bone formation process in RA. Dopamine receptors (DR) in the human bone tissue of RA or osteoarthritis (OA) patients were examined by immunohistochemistry. DR in isolated human osteoblasts (OB) was analyzed by flow cytometry, and dopamine content was evaluated by ELISA. Osteoclasts (OC) were differentiated from the PBMCs of healthy controls (HC) and RA patients. Isolated cells were treated with specific dopamine agonists. The effect of dopamine on mineralization was evaluated by Alizarin red staining. Cytokine release in supernatants was measured by ELISA. Osteoclastogenesis was evaluated with TRAP staining. OC markers were analyzed via real-time PCR and bone resorption via staining of resorption pits with toluidine blue. All DR were observed in bone tissue, especially in the bone remodeling area. Isolated OB maintained DR expression, which allowed their study in vitro. Isolated OB expressed tyrosine hydroxylase, the rate-limiting enzyme for dopamine production, and contained dopamine. The activation of D2-like DR significantly increased bone mineralization in RA osteoblasts and increased osteoclastogenesis but did not alter the expression of OC markers nor bone resorption. DR were found in the bone remodeling area of human bone tissue and dopamine can be produced by osteoblasts themselves, thus suggesting a local autocrine/paracrine pathway of dopamine in the bone. D2-like DRs are responsible for bone mineralization in osteoblasts from RA patients without an increase in bone resorption, thus suggesting the D2-like DR pathway as a possible future therapeutic target to counteract bone resorption in arthritis.

The second decade of anti-TNF-a therapy in clinical practice: new lessons and future directions in the COVID-19 era

Since the late 1990s, tumor necrosis factor alpha (TNF-α) inhibitors (anti-TNFs) have revolutionized the therapy of immune-mediated inflammatory diseases (IMIDs) affecting the gut, joints, skin and eyes. Although the therapeutic armamentarium in IMIDs is being constantly expanded, anti-TNFs remain the cornerstone of their treatment. During the second decade of their application in clinical practice, a large body of additional knowledge has accumulated regarding various aspects of anti-TNF-α therapy, whereas new indications have been added. Recent experimental studies have shown that anti-TNFs exert their beneficial effects not only by restoring aberrant TNF-mediated immune mechanisms, but also by de-activating pathogenic fibroblast-like mesenchymal cells. Real-world data on millions of patients further confirmed the remarkable efficacy of anti-TNFs. It is now clear that anti-TNFs alter the physical course of inflammatory arthritis and inflammatory bowel disease, leading to inhibition of local and systemic bone loss and to a decline in the number of surgeries for disease-related complications, while anti-TNFs improve morbidity and mortality, acting beneficially also on cardiovascular comorbidities. On the other hand, no new safety signals emerged, whereas anti-TNF-α safety in pregnancy and amid the COVID-19 pandemic was confirmed. The use of biosimilars was associated with cost reductions making anti-TNFs more widely available. Moreover, the current implementation of the “treat-to-target” approach and treatment de-escalation strategies of IMIDs were based on anti-TNFs. An intensive search to discover biomarkers to optimize response to anti-TNF-α treatment is currently ongoing. Finally, selective targeting of TNF-α receptors, new forms of anti-TNFs and combinations with other agents, are being tested in clinical trials and will probably expand the spectrum of TNF-α inhibition as a therapeutic strategy for IMIDs.

The Lived Experiences of Iranian Patients with Rheumatoid Arthritis: A Qualitative Research

BACKGROUND

Rheumatoid Arthritis (RA) is a chronic inflammatory disease that affects various systems of the body. The present study was conducted with the aim to explain the lived experiences of Iranian patients with RA.

MATERIALS AND METHODS

According to the research question, the phenomenological research approach was used. The participants were selected through purposive sampling, and sampling was continued until data saturation was achieved. The data was collected by conducting unstructured interviews and using an audio recorder. To interpret the data, an interpretive/hermeneutic approach was implemented using Van Manen's method. In addition, Lincoln and Guba's criteria were used to evaluate data robustness.

RESULTS

A total of 24 participants participated in the study. Overall, 145 basic concept codes were extracted which were classified into the four main themes of self-management with the participation of the family, spiritual resilience in the face of existing problems, the tendency to hide the disease, and the fear of an uncertain future.

CONCLUSIONS

It is recommended that care providers use the findings of this study to develop care plans in the various aspects of the physical, mental, social, and spiritual needs of patients with RA based on their concerns and deep experiences. It is also suggested that other qualitative research approach methodologies such as grounded theory for explaining the process of patient care and providing an appropriate model, or action research for solving the problems of hospitalized patients through suitable care at home be implemented.

Bone Mineral Density and Current Bone Health Screening Practices in Friedreich's Ataxia

Introduction

Friedreich's Ataxia (FRDA) is a progressive neurological disorder caused by mutations in both alleles of the frataxin (FXN) gene. Impaired bone health is a complication of other disorders affecting mobility, but there is little information regarding bone health in FRDA.

Methods

Dual energy X-ray absorptiometry (DXA) scan-based assessments of areal bone mineral density (aBMD) in individuals with FRDA were abstracted from four studies at the Children's Hospital of Philadelphia (CHOP). Disease outcomes, including the modified FRDA Rating Scale (mFARS), were abstracted from the FRDA Clinical Outcomes Measures Study (FACOMS), a longitudinal natural history study. A survey regarding bone health and fractures was sent to individuals in FACOMS-CHOP.

Results

Adults with FRDA (n = 24) have lower mean whole body (WB) (-0.45 vs. 0.33, p = 0.008) and femoral neck (FN) (-0.71 vs. 0.004, p = 0.02) aBMD Z-scores than healthy controls (n = 24). Children with FRDA (n = 10) have a lower WB-less-head (-2.2 vs. 0.19, p < 0.0001) and FN (-1.1 vs. 0.04, p = 0.01) aBMD than a reference population (n = 30). In adults, lower FN aBMD correlated with functional disease severity, as reflected by mFARS (R = -0.56, p = 0.04). Of 137 survey respondents (median age 27 y, 50% female), 70 (51%) reported using wheelchairs as their primary ambulatory device: of these, 20 (29%) reported a history of potentially pathologic fracture and 11 (16%) had undergone DXA scans.

Conclusions

Low aBMD is prevalent in FRDA, but few of even the highest risk individuals are undergoing screening. Our findings highlight potential missed opportunities for the screening and treatment of low aBMD in FRDA.

Effects of targeted therapies on bone in rheumatic and musculoskeletal diseases

Generalized bone loss (osteoporosis) and fragility fractures can occur in rheumatic and musculoskeletal diseases including rheumatoid arthritis and spondyloarthritis (SpA; including ankylosing spondylitis and psoriatic arthritis). In addition, rheumatoid arthritis can involve localized, periarticular bone erosion and, in SpA, local (pathological) bone formation can occur. The RANK-RANKL-osteoprotegerin axis and the Wnt-β-catenin signalling pathway (along with its inhibitors sclerostin and Dickkopf 1) have been implicated in inflammatory bone loss and formation, respectively. Targeted therapies including biologic DMARDs and Janus kinase (JAK) inhibitors can stabilize bone turnover and inhibit radiographic joint damage, and potentially also prevent generalized bone loss. Targeted therapies interfere at various points in the mechanisms of local and generalized bone changes in systemic rheumatic diseases, and they effect biomarkers of bone resorption and formation, bone mass and risk of fragility fractures. Studies on the effects of targeted therapies on rates of fragility fracture are scarce. The efficacy of biologic DMARDs for arresting bone formation in axial SpA is debated. Improved understanding of the most relevant therapeutic targets and identification of important targeted therapies could lead to the preservation of bone in inflammatory rheumatic and musculoskeletal diseases.

Drug Treatment of Low Bone Mass and Other Bone Conditions in Pediatric Patients

Osteoporosis may affect young individuals, albeit infrequently. In childhood, bone mass increases, reaching its peak between the second and third decades; then, after a period of stability, it gradually declines. Several conditions, including genetic disorders, chronic diseases, and some medications, can have an impact on bone homeostasis. Diagnosis in young patients is based on the criteria defined by the International Society for Clinical Densitometry (ISCD), published in 2013. High risk factors should be identified and monitored. Often simple interventions aimed to eliminate the underlying cause, to minimize the negative bone effects linked to drugs, or to increase calcium and vitamin D intake can protect bone mass. However, in selected cases, pharmacological treatment should be considered. Bisphosphonates remain the main therapeutic agent for children with significant skeletal fragility and are also useful in a large number of other bone conditions. Denosumab, an anti-RANKL antibody, could become a potential alternative treatment. Clinical trials to evaluate the long-term effects and safety of denosumab in children are ongoing.

Incidence and risk factors for vertebral fracture in rheumatoid arthritis: an update meta-analysis

OBJECTIVES

This study was conducted to investigate the prevalence of vertebral fracture (VF) and its risk in patients with rheumatoid arthritis (RA) as compared to healthy individuals, and to explore the underlying risk factors.

METHODS

The electronic databases of PubMed, EMBASE, and the Cochrane Library were applied to search for the relevant literatures, which reported the prevalence of VF in both RA patients and healthy controls (up to Mar 31, 2021). The non-weighted prevalence of VF, pooled estimates of odds ratio (OR), and its 95% confidence intervals (CI) were calculated with the use of random-effects model; between-study heterogeneity was evaluated by Cochrane Q statistic, then was quantified with I². Publication bias was evaluated using Egger's linear regression test.

RESULTS

A number of 867 literatures were identified after searching for online databases, based on the inclusion and exclusion criteria, 11 eligible studies, which comprising 3805 RA patients and 59,517 healthy participants, were finally incorporated in meta-analysis. The results showed that RA patients had an increased prevalence of VF (20.29 vs 8.63%), and an elevated risk for VF (OR = 3.04, 95% CI 1.97-4.71) as compared to healthy population. Additional subgroup analysis suggested that age, body mass index (BMI), disease activity, and drug therapy might be associated with risk of VF in RA.

CONCLUSIONS

Overall, our study demonstrated an increased risk of VF in patients with RA, suggesting that age, race, BMI, disease activity, and drug therapy may be represented as risk factors contributing to the occurrence of VF in RA. Key Points • RA patients had the increased prevalence and risk of vertebral fracture (VF) as compared to healthy population. • Age, race, BMI, disease activity, and drug therapy might be associated with VF in RA. • Our findings would be helpful for the early evaluation of RA patients with high VF risk.

Yi Shen Juan Bi Pill Regulates the Bone Immune Microenvironment via the JAK2/STAT3 Signaling Pathway in Vitro

Rheumatoid arthritis (RA) is characterized by an impaired articular bone immune microenvironment, which is associated with regulatory T cells (Tregs) hypofunction and osteoclasts (OCs) hyperfunction and leads to articular bone erosion and systemic bone loss. Studies have shown that Tregs slow bone loss in RA by regulating the bone resorption function of OCs and the JAK/STAT signaling pathway can regulate the immunosuppressive function of Tregs and reduce the bone erosion function of OCs. Yi Shen Juan Bi Pill (YSJB) is a classic Chinese herbal compound for the treatment of RA. However, whether YSJB regulates bone immune microenvironment homeostasis through JAK/STAT signaling pathway remains unclear. Based on in vitro OC single culture, Treg single culture and OC-Treg coculture systems, treatments were performed using drug-containing serum, AG490 and JAK2 siRNA to explore whether YSJB-containing serum regulates the homeostasis of the bone immune microenvironment through the JAK/STAT signaling pathway. In vitro, YSJB treatment decreased the number of TRAP⁺ cells and the areas of bone resorption and inhibited the expression of RANK, NFATc1, c-fos, JAK2, and STAT3 in both the OC single culture system and the OC-Treg coculture system. Tregs further reduced the number of TRAP⁺ cells and the areas of bone resorption in the coculture system. YSJB promoted the secretion of IL-10 while inhibiting the expression of JAK2 and STAT3 in Tregs. Moreover, inhibiting the expression of JAK2 with the JAK2 inhibitor AG490 and JAK2 siRNA improved the immunosuppressive functions of Treg, inhibited OC differentiation and bone resorption. Our study demonstrates that YSJB can regulate OC-mediated bone resorption and Treg-mediated bone immunity through the JAK2/STAT3 signaling pathway. This study provides a new strategy for regulating the bone immune microenvironment in RA with traditional Chinese medicine.

Peficitinib improves bone fragility by recovering bone turnover imbalance in arthritic mice

Peficitinib, a pan-JAK inhibitor, is known to suppress the activation of fibroblast-like synoviocytes (FLSs) and thereby reduces joint inflammation associated with rheumatoid arthritis (RA). However, the effect on osteoporosis in RA remains to be elucidated. In this study, the effect of peficitinib or etanercept on joint inflammation, and consequently decreased bone mineral density (BMD) was evaluated in mice with collagen-induced arthritis (CIA). Additionally, the effect on RANKL production from osteoblasts differentiated from the mesenchymal stem cells of RA patients was evaluated. Administration of peficitinib for established CIA ameliorated arthritis and improved BMD in the femoral metaphysis, but not in the femoral diaphysis. Conversely, etanercept suppressed an increase in synovial inflammatory markers but did not improve arthritic conditions or the reduction of BMD in either region. All elevated bone formation and bone resorption markers were decreased with peficitinib but only partially decreased with etanercept. Furthermore, production of RANKL by human osteoblasts was suppressed by peficitinib but enhanced by etanercept. Unlike etanercept, peficitinib is thought to increase BMD by ameliorating the high bone turnover associated with RA states, resulting in improvement of bone fragility. Our data provide evidence that peficitinib would be expected to show efficacy for osteoporosis associated with RA.

Mapping Knowledge Structure and Themes Trends of Osteoporosis in Rheumatoid Arthritis: A Bibliometric Analysis

Background: Rheumatoid arthritis is a chronic disabling disease characterized by chronic inflammation, articular cartilage destruction, and reduced bone mass. Multiple studies have revealed that the development of osteoporosis in rheumatoid arthritis (RA; ORA) patients could be led to a reduced quality of life and increased healthcare costs. Nevertheless, no attempt has been made to analyze the field of ORA research with the bibliometric method. This study aimed to provide a comprehensive overview of the knowledge structure and theme trends in the field of ORA research from a bibliometric perspective.

Methods: Articles and reviews regarding ORA from 1998 to 2021 were identified from the Web of Science database. An online bibliometric platform, CiteSpace, and VOSviewer software were used to generate visualization knowledge maps including co-authorship, co-citation, and co-occurrence analysis. SPSS, R, and Microsoft Excel software were used to conduct curve fitting and correlation analysis, and to analyze quantitative indicators, such as publication and citation counts, h-index, and journal citation reports.

Results: A total of 1,081 papers with 28,473 citations were identified. Publications were mainly concentrated in North America, Western Europe, and Eastern Asia. Economic strength is an important factor affecting scientific output. The United States contributed the most publications (213) with the highest h-index value (46) as of September 14, 2021. Diakonhjemmet Hospital and professor Haugeberg G were the most prolific institution and influential authors, respectively. Journal of Rheumatology was the most productive journal concerning ORA research. According to the burst references, “anti-citrullinated protein antibodies” and “preventing joint destruction” have been recognized as the hot research issues in the domain. The keywords co-occurrence analysis identified “teriparatide,” “interleukin-6,” “Wnt,” and “vertebral fractures” as the important future research directions.

Conclusion: This was the first bibliometric study comprehensively summarizing the trends and development of ORA research. Our findings could offer practical sources for scholars to understand the key information in this field, and identify the potential research frontiers and hot directions in the near future.

Rheumatoid Arthritis is a Risk Factor for Refracture in Patients with Fragility Fractures

OBJECTIVES

To determine whether patients with rheumatoid arthritis (RA) who have had fragility fractures are at an increased risk of refractures.

METHODS

Patients with fragility fractures who were treated surgically at ten hospitals from 2008 to 2017 and who underwent follow-up for more than 24 months were either categorized into a group comprising patients with RA or a group comprising patients without RA (controls). The groups were matched 1:1 by propensity score matching. Accordingly, 240 matched participants were included in this study. The primary outcome was the refracture rate in patients with RA as compared to in the controls. Multivariable analyses were also conducted on patients with RA to evaluate the odds ratios (ORs) for the refracture rates.

RESULTS

Patients with RA were significantly associated with increased rates of refractures during the first 24 months (OR: 2.714, 95% confidence interval [95% CI]: 1.015-7.255; P = 0.040). Multivariable analyses revealed a significant association between increased refracture rates and long-term RA (OR: 6.308, 95% CI: 1.195-33.292; P=0.030).

CONCLUSIONS

Patients with RA who have experienced fragility fractures are at an increased risk of refractures. Long-term RA is a substantial risk factor for refractures.

Effects of romosozumab or denosumab treatment on the bone mineral density and disease activity for 6 months in patients with rheumatoid arthritis with severe osteoporosis: An open-label, randomized, pilot study

Objectives

To investigate effects of romosozumab treatment on disease activity and bone mineral density (BMD) in patients with rheumatoid arthritis (RA) and severe osteoporosis in comparison with effects of denosumab treatment.

Methods

A total of 50 women were enrolled in this study. The subjects were randomized equally into 2 groups: the romosozumab group or the denosumab group. Disease activity score in 28 joints (DAS28)-erythrocyte sedimentation rate (ESR) and BMD at lumbar spine were evaluated.

Results

The percent changes (Δ) in the BMD values at 3 and 6 months for the lumbar spine were as follows: romosozumab; 4.9% and 5.2%, denosumab: 2.3% and 3.2%. The ΔBMD for the lumbar spine at 3 months was significantly higher in the romosozumab group than in the denosumab group (P = 0.044). The DAS28-ESR at baseline, 3 and 6 months in the romosozumab group were 2.88, 2.60 (P = 0.427) and 2.58 (P = 0.588), respectively. The change from baseline in DAS28-ESR did not differ significantly between these 2 groups at any time point.

Conclusions

The present study revealed that romosozumab treatment is more effective than denosumab treatment in increasing BMD of the lumbar spine at 3 months. Furthermore, the present study suggested that romosozumab treatment has no effects on the disease activity of RA in patients with RA and severe osteoporosis for 6 months.

Risk of Non-Vertebral Fracture in Gout Compared to Rheumatoid Arthritis

Objective: To evaluate the risk of non-vertebral fractures in patients with gout compared with those with rheumatoid arthritis (RA). Methods: Using claims data from Medicare (2008–2015), we conducted a cohort study of patients with gout versus RA matched on age, sex, and index date with a 1:1 ratio. The primary outcome was a composite endpoint of non-vertebral fractures including hip, pelvis, humerus, and wrist identified with the validated algorithms. We also assessed hip fractures separately. Multivariable Cox proportional hazards regression estimated the hazard ratio (HR) for the outcomes in gout versus RA adjusted for 45 covariates. Results: We included a total of 134,157 matched pairs of gout and RA patients (mean age: 73.7 years). Risk factors for fracture were more prevalent in RA, while other comorbidities including obesity, coronary heart disease, hypertension, and diabetes were more common in gout. Over the mean 2.8 years follow-up, the incidence rate (IR)/1000 person-year (PY) of non-vertebral fractures was 10.42 in gout and 15.01 in RA. For hip fractures, the IR/1000 PY was 4.86 in gout and 7.73 in RA. The multivariable HR associated with gout versus RA was 0.84 (95% confidence interval (CI) 0.80–0.88) for non-vertebral fractures and 0.76 (95% CI 0.71–0.82) for hip fractures. Stratified analyses by age, sex, prior fractures, steroid use, and TNF inhibitor use showed similar results. Conclusions: In this large cohort of older patients, gout was associated with a modestly decreased risk of non-vertebral or hip fractures versus RA. However, non-vertebral fractures occurred frequently in both gout and RA.

Cytokine Networks in the Pathogenesis of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic systemic inflammation causing progressive joint damage that can lead to lifelong disability. The pathogenesis of RA involves a complex network of various cytokines and cells that trigger synovial cell proliferation and cause damage to both cartilage and bone. Involvement of the cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6 is central to the pathogenesis of RA, but recent research has revealed that other cytokines such as IL-7, IL-17, IL-21, IL-23, granulocyte macrophage colony-stimulating factor (GM-CSF), IL-1β, IL-18, IL-33, and IL-2 also play a role. Clarification of RA pathology has led to the development of therapeutic agents such as biological disease-modifying anti-rheumatic drugs (DMARDs) and Janus kinase (JAK) inhibitors, and further details of the immunological background to RA are emerging. This review covers existing knowledge regarding the roles of cytokines, related immune cells and the immune system in RA, manipulation of which may offer the potential for even safer and more effective treatments in the future.

Predictors of acromial and scapular stress fracture after reverse shoulder arthroplasty: a study by the ASES Complications of RSA Multicenter Research Group

BACKGROUND

Acromial (ASF) and scapular spine (SSF) stress fractures are well-recognized complications of reverse shoulder arthroplasty (RSA), but much of the current data are derived from single-center or single-implant studies with limited generalizability. This study from the American Shoulder and Elbow Surgeons (ASES) Complications of Reverse Shoulder Arthroplasty Multicenter Research Group determined the incidence of ASF/SSF after RSA and identified preoperative patient characteristics associated with their occurrence.

METHOD

Fifteen institutions including 21 ASES members across the United States participated in this study. Patients undergoing either primary or revision RSA between January 2013 and June 2019 with a minimum 3-month follow-up were included. All definitions and inclusion criteria were determined using the Delphi method, an iterative survey process involving all primary investigators. Consensus was achieved when at least 75% of investigators agreed on each aspect of the study protocol. Only symptomatic ASF/SSF diagnosed by radiograph or computed tomography were considered. Multivariable logistic regression was performed to identify factors associated with ASF/SSF development.

RESULTS

We identified 6755 RSAs with an average follow-up of 19.8 months (range, 3-94). The total stress fracture incidence rate was 3.9% (n = 264), of which 3.0% (n = 200) were ASF and 0.9% (n = 64) were SSF. Fractures occurred at an average 8.2 months (0-64) following RSA with 21.2% (n = 56) following a trauma. Patient-related factors independently predictive of ASF were chronic dislocation (odds ratio [OR] 3.67, P = .04), massive rotator cuff tear without arthritis (OR 2.51, P < .01), rotator cuff arthropathy (OR 2.14, P < .01), self-reported osteoporosis (OR 2.21, P < .01), inflammatory arthritis (OR 2.18, P < .01), female sex (OR 1.51, P = .02), and older age (OR 1.02 per 1-year increase, P = .02). Factors independently associated with the development of SSF included osteoporosis (OR 2.63, P < .01), female sex (OR 2.34, P = .01), rotator cuff arthropathy (OR 2.12, P = .03), and inflammatory arthritis (OR 2.05, P = .03).

CONCLUSION

About 1 in 26 patients undergoing RSA will develop a symptomatic ASF or SSF, more frequently within the first year of surgery. Our results indicate that severe rotator cuff disease may play an important role in the occurrence of stress fractures following RSA. This information can be used to counsel patients about potential setbacks in recovery, especially among older women with suboptimal bone health. Strategies for prevention of ASF and SSF in these at-risk patients warrant further study. A follow-up study evaluating the impact of prosthetic factors on the incidence rates of ASF and SSF may prove highly valuable in the decision-making process.

Bone-sparing effects of rituximab and body composition analysis in a cohort of postmenopausal women affected by rheumatoid arthritis - retrospective study

Objective

Osteoporosis is the most common bone tissue disease and it is characterized by a reduced bone mineral density (BMD). The main physiopathological mechanisms converge on the uncoupling between bone formation and resorption, thus leading to an enhanced risk of fractures. Several papers have documented the inverse relationships linking high inflammatory cytokines, anti-citrullinated protein antibodies, rheumatoid factor, and BMD in rheumatoid arthritis (RA). Rituximab (RTX) is a chimeric monoclonal antibody directed against the CD20 receptor of B cells. Since the Food and Drug Administration approved it for RA in 2006, there have been many clinical experiences regarding its use. Nevertheless, few studies evaluate the effect of rituximab on BMD. RA is a disease characterized by immune dysfunction with high levels of inflammatory cytokines, autoantibodies, and it is reasonable that a B cell depleting therapy could restore a physiological cytokine balance, thus exerting an osteoprotective effect on the bone tissue. The purpose of this paper is to highlight any difference in BMD and to assess differences in body composition over a retrospective 18-month follow-up period after RTX treatment with a B cell depleting therapy.

Material and methods

We analyzed by dual energy X-ray absorptiometry BMD expressed as g/cm² and body composition modifications over 18 months with RTX treatment of 20 postmenopausal RA patients.

Results

After eighteen months of therapy with RTX, a statistically significant increase in vertebral (L1–L4) BMD and the stability of femoral BMD were documented.

Conclusions

Rituximab is associated with an improvement of vertebral and preservation of femoral BMD, suggesting a bone-sparing effect due to B cell depletion. Furthermore, patients displayed a redistribution of fat masses toward the hip region.

The role of renin angiotensin system in the pathophysiology of rheumatoid arthritis

BACKGROUND

In rheumatoid arthritis (RA) and osteoarthritis (OA), chronic inflammatory processes lead to progresive joint destruction. The renin-angiotensin system (RAS) is involved in the pathogenesis of RA and OA. The aim of this mini-review article is to summarize evidence on the role of RAS in RA and OA.

METHODS

A non-systematic search in Pubmed included terms as "rheumatoid arthritis", "renin angiotensin system", "osteopenia", "RANKL", "DKK-1", "MMP", "inflammation", "angiogenesis", "local renin-angiotensin system", "angiotensin converting enzyme", "AT2 receptor", "Ang-(1-7)", "VEGF", "angiotensine receptor blocker", "angiotensin converting enzyme inhibitors", "renin inhibitors".

RESULTS

Both RAS axes, the classical one, formed by angiotensin converting enzyme (ACE), angiotensin (Ang) II and AT1 receptor (AT1R) and the counter-regulatory one, composed by ACE2, Ang-(1-7) and the Mas receptor, modulate inflammation and tissue damage. Ang II activates pro-inflammatory mediators and oxidative stress. Conversely, Ang-(1-7) exerts anti-inflammatory actions, decreasing cytokine release, leukocyte attraction, density of vessels, tissue damage and fibrosis. Angiogenesis facilitates inflammatory cells invasion, while osteopenia causes joint dysfunction. Up-regulated osteoclastogenisis and down-regulated osteoblastogeneses were associaed with the activation of the classical RAS axis. Three different pathways, RANKL, DKK-1 and MMPs are enhanced by classical RAS activation. The treatment of RA included methotrexate and corticosteroids, which can cause side effects. Studies with angiotensin receptor blockers (ARBs), angiotensin converting enzyme inhibitors (ACEi) and renin inhibitors have been conducted in experimental and clinical RA with promising results.

CONCLUSION

The classical RAS activation is an important mechanism in RA pathogenesis and the benefit of ARB and ACEi administration should be further investigated.