Osteoporosis and rheumatic diseases

Bone erosions associated with systemic bone loss on HR-pQCT in women with longstanding polyarticular juvenile idiopathic arthritis

OBJECTIVES

To analyze longstanding polyarticular juvenile idiopathic arthritis (pJIA) for possible associations between localized bone damage (erosions), and systemic bone loss. Besides, to compare the systemic bone mass of pJIA with healthy controls.

METHODS

Thirty-four pJIA women and 99 healthy controls (HC) were included. Radius and tibia of all subjects were scanned by HR-pQCT. Volumetric bone mineral density (vBMD), bone microarchitecture, and -finite element parameters were analyzed. Patients underwent HR-pQCT of 2nd and 3rd metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints of the dominant hand, for bone erosions quantification.

RESULTS

The mean age of patients was 31.5 ± 7.4yrs with a mean disease duration of 21.7 ± 9.2yrs. Bone erosions were detectable in 79% of patients. The number of bone erosions was positively correlated with cortical porosity (Ct.Po) at tibia (r = 0.575, p = 0.001), and radius (r = 0.423, p = 0.018); and negatively correlated with cortical vBMD at tibia (r=-0.420, p = 0.015). In a logistic regression analysis, adjusted for anti-CCP, the presence of bone erosions was independently associated with Ct.Po at radius (p = 0.018) and cortical vBMD at tibia (p = 0.020). Moreover, cortical and trabecular vBMD, trabecular number, and μ-finite element parameters were decreased in patients compared to HC (p < 0.05).

CONCLUSION

Bone erosions in longstanding pJIA women were associated with decreased cortical bone parameters, and these patients showed systemic bone impairment at peripheral sites compared with healthy controls.

Bone Involvement in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by a wide variability of clinical manifestations due to the potential involvement of several tissues and internal organs, with a relapsing and remitting course. Dysregulation of innate and adaptive immune systems, due to genetic, hormonal and environmental factors, may be responsible for a broad spectrum of clinical manifestations, affecting quality of life, morbidity and mortality. Bone involvement represents one of the most common cause of morbidity and disability in SLE. Particularly, an increased incidence of osteoporosis, avascular necrosis of bone and osteomyelitis has been observed in SLE patients compared to the general population. Moreover, due to the improvement in diagnosis and therapy, the survival of SLE patient has improved, increasing long-term morbidities, including osteoporosis and related fractures. This review aims to highlight bone manifestations in SLE patients, deepening underlying etiopathogenetic mechanisms, diagnostic tools and available treatment.

Efficacy of Denosumab for Osteoporosis in Patients with Rheumatic Diseases

Objective Denosumab, an anti-RANKL monoclonal antibody, was reported to improve bone mineral density (BMD) and reduce fracture risk, offering favorable efficacy against postmenopausal osteoporosis. However, some patients have experienced a reduced BMD despite denosumab therapy. Methods We performed an observational study to clarify the clinical efficacy of denosumab for osteoporosis in rheumatic disease patients. Serum levels of bone turnover markers and lumber BMD in 100 rheumatic disease patients were examined at baseline and 6 and 12 months after denosumab therapy. The independent influence of changes in the BMD was examined by multiple regression analyses adjusted for patient characteristics and bone turnover markers. Results As bone resorption markers, serum levels of N-telopeptide crosslinked of type I collagen (NTx) and tartrate-resistant acid phosphatase isoform 5b were statistically decreased after 12 months. As bone formation markers, serum levels of osteocalcin, procollagen type I N-terminal peptide, and bone alkaline phosphatase were significantly decreased after 12 months. The mean BMD was significantly increased after 12 months. However, in 10 patients, the BMD decreased. A multivariate analysis of factors related to BMD changes highlighted a young age, low prednisolone dosage, and reduction in NTx. Conclusions Denosumab increases the BMD to combat osteoporosis in rheumatic disease patients, and potential predictors of a better response to denosumab include a young age, reduction in bone turnover markers, and low-dose glucocorticoid use.

Gasdermin D deficiency attenuates arthritis induced by traumatic injury but not autoantibody-assembled immune complexes

BACKGROUND

Gasdermin D (GSDMD) is cleaved by several proteases including by caspase-1, a component of intracellular protein complexes called inflammasomes. Caspase-1 also converts pro-interleukin-1β (pro-IL-1β) and pro-IL-18 into bioactive IL-1β and IL-18, respectively. GSDMD amino-terminal fragments form plasma membrane pores, which mediate the secretion of IL-1β and IL-18 and cause the inflammatory form of cell death pyroptosis. Here, we tested the hypothesis that GSDMD contributes to joint degeneration in the K/BxN serum transfer-induced arthritis (STIA) model in which autoantibodies against glucose-6-phosphate isomerase promote the formation of pathogenic immune complexes on the surface of myeloid cells, which highly express the inflammasomes. The unexpected outcomes with the STIA model prompted us to determine the role of GSDMD in the post-traumatic osteoarthritis (PTOA) model caused by meniscus ligamentous injury (MLI) based on the hypothesis that this pore-forming protein is activated by signals released from damaged joint tissues.

METHODS

Gsdmd +/+ and Gsdmd-/- mice were injected with K/BxN mouse serum or subjected to MLI to cause STIA or PTOA, respectively. Paw and ankle swelling and DXA scanning were used to assess the outcomes in the STIA model whereas histopathology and micro-computed tomography (μCT) were utilized to monitor joints in the PTOA model. Murine and human joint tissues were also examined for GSDMD, IL-1β, and IL-18 expression by qPCR, immunohistochemistry, or immunoblotting.

RESULTS

GSDMD levels were higher in serum-inoculated paws compared to PBS-injected paws. Unexpectedly, ablation of GSDMD failed to reduce joint swelling and osteolysis, suggesting that GSDMD was dispensable for the pathogenesis of STIA. GSDMD levels were also higher in MLI compared to sham-operated joints. Importantly, ablation of GSDMD attenuated MLI-associated cartilage degradation (p = 0.0097), synovitis (p = 0.014), subchondral bone sclerosis (p = 0.0006), and subchondral bone plate thickness (p = 0.0174) based on histopathological and μCT analyses.

CONCLUSION

GSDMD plays a key role in the pathogenesis of PTOA, but not STIA, suggesting that its actions in experimental arthropathy are tissue context-specific.

Panax notoginseng saponins alleviate osteoporosis and joint destruction in rabbits with antigen-induced arthritis

Although a number of anti-rheumatic drugs and biologics may be used to alleviate the symptoms of rheumatoid arthritis (RA), these compounds have been associated with bone loss and joint destruction; thus, alternative treatment approaches are required. In the present study, various plant extracts were evaluated for their capacity to inhibit joint destruction, and Panax notoginseng saponins (PNS), obtained from the Traditional Chinese Medicine Panax notoginseng, was identified as such a compound. Therefore, a rabbit antigen-induced arthritis (AIA) model was generated by immunization with ovalbumin in Freund's complete adjuvant, followed by treatment with PNS for 3 months. The morphology of the quadriceps femoris muscle, cartilage chondrocytes and skeletal elements was histologically observed by transmission electron microscopy (TEM), as well as micro-computed tomography. The results revealed that PNS significantly reduced the histopathological alterations associated with arthritic muscular atrophy and inflammation. In addition, TEM demonstrated that PNS protected chondrocytes from RA-associated damage. Furthermore, the bone density and microarchitecture in rabbits treated with PNS were markedly improved compared with those of the model group. Collectively, these data indicated that treatment with PNS may relieve osteoporosis and prevent joint and bone destruction in AIA.

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.

Age-related expansion and increased osteoclastogenic potential of myeloid-derived suppressor cells

Aging is associated with excessive bone loss that is not counteracted with the development of new bone. However, the mechanisms underlying age-related bone loss are not completely clear. Myeloid-derived suppressor cells (MDSCs) are a population of heterogenous immature myeloid cells with immunosuppressive functions that are known to stimulate tumor-induced bone lysis. In this study, we investigated the association of MDSCs and age-related bone loss in mice. Our results shown that aging increased the accumulation of MDSCs in the bone marrow and spleen, while in the meantime potentiated the osteoclastogenic activity of the CD11b⁺Ly6C^hiLy6G⁺ monocytic subpopulation of MDSCs. In addition, CD11b⁺Ly6C^hiLy6G⁺ MDSCs from old mice exhibited increased expression of c-fms compared to young mice, and were more sensitive to RANKL-induced osteoclast gene expression. On the other hand, old mice showed elevated production of IL-6 and receptor activator of nuclear factor kappa-B ligand (RANKL) in the circulation. Furthermore, IL-6 and RANKL were able to induce the proliferation of CD11b⁺Ly6C^hiLy6G⁺ MDSCs and up-regulate c-fms expression. Moreover, CD11b⁺Ly6C^hiLy6G⁺ MDSCs obtained from old mice showed increased antigen-specific T cell suppressive function, pStat3 expression, and cytokine production in response to inflammatory stimulation, compared to those cells obtained from young mice. Our findings suggest that CD11b⁺Ly6C^hiLy6G⁺ MDSCs are a source of osteoclast precursors that together with the presence of persistent, low-grade inflammation, contribute to age-associated bone loss in mice.

Influence of glucocorticoid treatment on trabecular bone score and bone remodeling regulators in early rheumatoid arthritis

Background

Glucocorticoids (GC) modulate several regulators involved in the pathogenesis of bone changes in rheumatoid arthritis (RA). Trabecular bone score (TBS) allows the indirect assessment of bone quality. The aim of this study was to investigate the effects of GC on TBS and serum levels of bone turnover regulators in patients with recent-onset RA.

Materials and methods

Forty-seven subjects with recent-onset RA (< 6 months) were classified in two groups, low (lGC) and high (hGC) glucocorticoids, according to glucocorticoid dose regimens. Bone mineral density (BMD), TBS, and circulating Dickkopf-1 (Dkk1), sclerostin, osteoprotegerin (OPG), and RANK-L were evaluated at baseline and 6 and 12 months.

Results

BMD significantly declined after 12 months with no significant difference between the lGC and hGC group, whereas TBS decreased in the hGC group only. Circulating OPG decreased during the follow-up period, the reduction being significantly greater in hGC group; conversely, sclerostin and RANK-L serum increased, in a significantly greater extent in the hGC group. TBS inversely correlated with sclerostin, RANK-L, and Dkk1 circulating levels whereas directly correlated with OPG circulating levels. GC cumulative dose showed an inverse relationship with BMD in both the hGC and lGC groups; TBS values showed an inverse relationship with GC cumulative dose in the hGC group only. GC cumulative dose was associated to higher sclerostin and lower OPG serum levels. TBS did not correlate with disease activity whereas BMD was inversely related to disease activity.

Conclusions

In early RA, GC exposure contributes to the reduction of BMD and affects bone quality depending on dose regimens. TBS could be a useful tool to evaluate the negative effect of GC on bone microarchitecture.

Trial registration

This study was ancillary to a parallel-group observational prospective study which was approved by the medical local ethics committee (protocol number DDG 334/19-06-2019).

Assessment of in vivo bone microarchitecture changes in an anti-TNFα treated psoriatic arthritic patient

Objective

Psoriatic arthritis (PsA) is an inflammatory rheumatic disease, mediated in part by TNFα and associated with bone loss. Anti-TNFα treatment should inhibit this phenomenon and reduce the systemic bone loss. Ultra-high field MRI (UHF MRI) may be used to quantify bone microarchitecture (BM) in-vivo. In this study, we quantified BM using UHF MRI in a PsA patient and followed up the changes related to anti-TNFα treatment.

Subjects and methods

A non-treated PsA patient with knee arthritis and 7 gender-matched controls were scanned using a gradient re-echo sequence at UHF MRI. After a year of Adalimumab treatment, the patient underwent a second UHF MRI. A PET-FNa imaging was performed before and after treatment to identify and localize the abnormal metabolic areas. BM was characterized using typical morphological parameters quantified in 32 regions of interest (ROIs) located in the patella, proximal tibia, and distal femur.

Results

Before treatment, the BM parameters were statistically different from controls in 24/32 ROIs with differences reaching up to 38%. After treatment, BM parameters were normalized for 15 out of 24 ROIs. The hypermetabolic areas disclosed by PET-FNa before the treatment partly resumed after the treatment.

Conclusion

Thanks to UHF MRI, we quantified in vivo BM anomalies in a PsA patient and we illustrated a major reversion after one year of treatment. Moreover, BM results highlighted that the abnormalities were not only localized in hypermetabolic regions identified by PET-FNa, suggesting that the bone loss was global and not related to inflammation.

Bone health in idiopathic inflammatory myopathies

OBJECTIVE

To review the extant literature relating to bone health in the idiopathic inflammatory myopathies (IIM) including both adult and juvenile patients.

METHODS

A PubMed search® identified relevant studies from 1966 to 2020 in accordance with PRISMA guidelines. Two independent reviewers screened and extracted the abstracts/full manuscripts, and a third author was consulted in the case of disagreement.

RESULTS

We identified 37 articles (3 review articles, 2 RCTs, 9 cross-sectional, 16 cohort and 7 case-control studies). The prevalence of osteopenia (n = 7) ranges from 7 to 75% and osteoporosis (n = 7) between 13% to 27%. The prevalence of vertebral fractures ranged from 11 to 75%. Systemic inflammation likely contributes to reduced bone mineral density (BMD) in children with IIM but data is currently lacking in adult patients. Association between with impaired BMD and Vitamin D or calcium intake and physical activity has not been demonstrated in IIM. There is no clear consensus regarding the impact of age, menopause or BMI on bone health. Gender, smoking status, disease activity and inflammatory markers are not obvious independent predictors of low BMD. Several studies have demonstrated that glucocorticoids are associated with an increased risk of low BMD. There are no specific guidelines relating to the management of bone health in adult and juvenile patients with IIM.

CONCLUSION

Both adult and juvenile patients with IIM are at high risk of impaired bone health and fracture. The mechanisms behind this are likely multifactorial including systemic inflammation, glucocorticoid treatment, reduced mobility and impaired calcium/vitamin D homeostasis. There are a lack of guidelines and studies relating to the screening, prevention and treatment of impaired bone health in adult and juvenile patients with IIM. Future research is required to understand the complexity of bone health in IIM including to develop much needed disease-specific management recommendations.

Body composition and bone status in relation to microvascular damage in systemic sclerosis patients

AIM

To evaluate, in Systemic sclerosis (SSc) patients, the body composition and the bone status according to the peripheral microcirculatory condition, assessed and scored by nailfold videocapillaroscopy (NVC, "Early", "Active", "Late" patterns).

METHODS

Body composition and bone mineral density (BMD) were assessed by Dual X-ray absorptiometry and dedicated software (GE Lunar USA) in 37 female SSc patients classified according to the 2013 EULAR/ACR criteria and 40 sex-matched healthy subjects. Clinical, laboratory, body composition and bone parameters were analyzed according to the different NVC patterns. Means were compared by the Student's t test or one-way analysis of variance; medians were compared by the Kruskal-Wallis test; and frequencies by the chi-square test.

RESULTS

Higher prevalence of vertebral (21% vs 7%) and femoral (35% vs 7%) osteoporosis (OP) was found in SSc. Particularly SSc patients with "Late" NVC pattern showed a significantly higher prevalence of vertebral (p = 0.018) and femoral OP (p = 0.016). Regional assessment of bone mass (BM) in seven different body areas showed a significantly lower BMD only at the total spine (p = 0.008) and femoral neck (p = 0.027) in advanced microvascular damage. Patients with "Late" NVC pattern showed a lower whole-body lean mass (LM) compared to "Early" and "Active" NVC patterns, particularly at upper limbs. To note, in all body sites, BMD correlates with LM and BMC according to NVC pattern severity.

CONCLUSIONS

SSc patients with most severe microvascular damage show a significantly altered body composition and bone status suggesting a strong link between microvascular failure and associated muscle/bone sufferance.

Supervised Physical Therapy and Polymyositis/Dermatomyositis-A Systematic Review of the Literature

Objective: to find the most up-to-date evidence of the effectiveness and safety of supervised physical therapy in polymyositis/dermatomyositis patients. Methods: a systematic review of the literature in the main scientific databases was carried out. We searched for randomized controlled trials concerning supervised physical therapy and polymyositis/dermatomyositis. The PICOS method was used for the formulation of the clinical query. Methodological quality and the level of evidence of the included studies were assessed using the modified Jadad scale and the Oxford Centre for Evidence-Based Medicine Levels of Evidence guide, respectively. Results: a total of 2591 articles were found. By applying the inclusion/exclusion criteria, six randomized controlled clinical trials were admitted to the final phase of the review. The compared approaches concerned supervised exercise programs based on strategies of muscle strengthening or aerobic work. Following these exercises, an increase in the maximum rate of oxygen consumption, a decrease in creatine phosphokinase levels, an enhancement in the patient’s aerobic performance and an improvement in the quality of life indexes were registered. The methodological quality of the included studies ranged from 3 to 4.5. All the studies were classified as presenting an evidence level of 2b. Conclusions: supervised physical therapy in polymyositis/dermatomyositis is an effective, safe and free-of-contraindications tool to be used both in the acute and in the established phases of the pathology. However, further and higher-quality studies are necessary to confirm those findings, to clarify the timing of exercise delivery and to guide the choice towards different types of muscle contraction exercises.

Calcium physiology, metabolism and supplementation: a glance at patients with ankylosing spondylitis

The aim of this review is to describe the metabolism of calcium in ankylosing spondylitis compared to physiologic conditions, and to present the current evidence on the benefits and disadvantages of calcium supplementation in these patients. A narrative review of the literature was conducted using the PubMed database and a total of 65 articles were selected. Calcium is involved in many physiopathological processes, including inflammation, bone loss and bone formation, all of which occur in ankylosing spondylitis. Many ankylosing spondylitis patients suffer from concomitant osteopenia or osteoporosis, which represent indications for calcium supplementation. Conversely, there are still concerns about the use of calcium salts for the prevention of bone fragility in non-osteoporotic or non-osteopenic patients. In these cases, biologic agents may indirectly normalize calcium dysmetabolism by rebalancing the cytokine milieu, in turn associated with bone remodeling. Calcium supplements may be disadvantageous for entheseal calcifications, but so far there are no clear data confirming that such an association exists.

The Role of NLRP3 Inflammasome Activities in Bone Diseases and Vascular Calcification

Continuous stimulation of inflammation is harmful to tissues of an organism. Inflammatory mediators not only have an effect on metabolic and inflammatory bone diseases but also have an adverse effect on certain genetic and periodontal diseases associated with bone destruction. Inflammatory factors promote vascular calcification in various diseases. Vascular calcification is a pathological process similar to bone development, and vascular diseases play an important role in the loss of bone homeostasis. The NLRP3 inflammasome is an essential component of the natural immune system. It can recognize pathogen-related molecular patterns or host-derived dangerous signaling molecules, recruit, and activate the pro-inflammatory protease caspase-1. Activated caspase-1 cleaves the precursors of IL-1β and IL-18 to produce corresponding mature cytokines or recognizes and cleaves GSDMD to mediate cell pyroptosis. In this review, we discuss the role of NLRP3 inflammasome in bone diseases and vascular calcification caused by sterile or non-sterile inflammation and explore potential treatments to prevent bone loss.

The Emerging Role of Curcumin in the Modulation of TLR-4 Signaling Pathway: Focus on Neuroprotective and Anti-Rheumatic Properties

Natural products have been used in medicine for thousands of years. Given their potential health benefits, they have gained significant popularity in recent times. The administration of phytochemicals existed shown to regulate differential gene expression and modulate various cellular pathways implicated in cell protection. Curcumin is a natural dietary polyphenol extracted from Curcuma Longa Linn with different biological and pharmacological effects. One of the important targets of curcumin is Toll-like receptor-4 (TLR-4), the receptor which plays a key role in the modulation of the immune responses and the stimulation of inflammatory chemokines and cytokines production. Different studies have demonstrated that curcumin attenuates inflammatory response via TLR-4 acting directly on receptor, or by its downstream pathway. Curcumin bioavailability is low, so the use of exosomes, as nano drug delivery, could improve the efficacy of curcumin in inflammatory diseases. The focus of this review is to explore the therapeutic effect of curcumin interacting with TLR-4 receptor and how this modulation could improve the prognosis of neuroinflammatory and rheumatic diseases.

Accelerated immunosenescence in rheumatoid arthritis: impact on clinical progression

Patients with rheumatoid arthritis (RA) develop features of accelerated ageing, including immunosenescence. These changes include decreased thymic functionality, expansion of late-differentiated effector T cells, increased telomeric attrition, and excessive production of cytokines (senescence-associated secretory phenotype). The progression of RA has been associated with the early development of age-related co-morbidities, including osteoporosis, cardiovascular complications, and cognitive impairment. Here I review data supporting the hypothesis that immune-senescence contributes to the aggravation of both articular and extra-articular manifestations. Of note, poor cognitive functions in RA were associated with senescent CD28- T cells, inflammaging, and autoantibodies against brain antigens. The pathways of immune-to-brain communication are discussed and provide the rationale for the cognitive impairment reported in RA.

Cytokines in Inflammatory Disease

This review aims to briefly discuss a short list of a broad variety of inflammatory cytokines. Numerous studies have implicated that inflammatory cytokines exert important effects with regard to various inflammatory diseases, yet the reports on their specific roles are not always consistent. They can be used as biomarkers to indicate or monitor disease or its progress, and also may serve as clinically applicable parameters for therapies. Yet, their precise role is not always clearly defined. Thus, in this review, we focus on the existing literature dealing with the biology of cytokines interleukin (IL)-6, IL-1, IL-33, tumor necrosis factor-alpha (TNF-α), IL-10, and IL-8. We will briefly focus on the correlations and role of these inflammatory mediators in the genesis of inflammatory impacts (e.g., shock, trauma, immune dysregulation, osteoporosis, and/or critical illness).

Wnt Signaling and Biological Therapy in Rheumatoid Arthritis and Spondyloarthritis

The Wnt signaling pathway plays a key role in several biological processes, such as cellular proliferation and tissue regeneration, and its dysregulation is involved in the pathogenesis of many autoimmune diseases. Several evidences support its role especially in bone complications of rheumatic diseases. In Rheumatoid Arthritis (RA), the Wnt signaling is implicated in systemic and localized bone loss, while available data of its role in Spondyloarthritis (SpA) are conflicting. In the last few decades, the quality of life of rheumatic patients has been dramatically improved by biological therapy, targeting cytokines involved in the pathogenesis of these diseases like tumor necrosis factor (TNF)α, interleukin (IL)-1, IL-6, IL-17. In this review, we reviewed the role of Wnt signaling in RA and SpA, focusing on the effect of biological therapy on this pathway and its possible clinical implications.

Omnipresence of inflammasome activities in inflammatory bone diseases

The inflammasomes are intracellular protein complexes that are assembled in response to a variety of perturbations including infections and injuries. Failure of the inflammasomes to rapidly clear the insults or restore tissue homeostasis can result in chronic inflammation. Recurring inflammation is also provoked by mutations that cause the constitutive assembly of the components of these protein platforms. Evidence suggests that chronic inflammation is a shared mechanism in bone loss associated with aging, dysregulated metabolism, autoinflammatory, and autoimmune diseases. Mechanistically, inflammatory mediators promote bone resorption while suppressing bone formation, an imbalance which over time leads to bone loss and increased fracture risk. Thus, while acute inflammation is important for the maintenance of bone integrity, its chronic state damages this tissue. In this review, we discuss the role of the inflammasomes in inflammation-induced osteolysis.

Bone mineral density and serum osteocalcin levels in patients with gout

Objective: The objective of the study is to evaluate the relation of gout with osteoporosis and serum osteocalcin (OC) levels. Material and methods: Seventy-five patients diagnosed with gout and 55 controls were included in the study. Comorbid conditions and drugs associated with osteoporosis were excluded. The T and Z scores from lumbar spine (L2-L4) and femur (neck, ward, trochanter, total) were determined by dual-energy X-ray absorptiometry (DXA). OC levels were measured by enzyme-linked immunosorbent assay. Results: Osteoporosis according to T scores of lumbar vertebrae L2-L4 was found to be significantly higher in patients with gout compared to the control group (p = 0.02). Lumbar spine T-score was -1.6 in gout group and -1.0 in controls. OC level was 7.9 ng/mL in the gout group and 18.9 ng/mL in the control group. There was a significant difference (p < 0.001). In addition, mean OC level was 12.4 ± 6.9 ng/mL in the patients diagnosed with osteoporosis and 17.2 ± 10.6 ng/mL in the patients that were classified as normal and a significant difference was established between the two groups (p = 0.03). A significant negative correlation was found between OC level and body mass index, age, and age at first attack. Similarly, femoral T-score established a negative correlation with parathyroid hormone, age, age at first attack, and allopurinol dose. Conclusion: Serum OC level can be a useful marker in the assessment of bone turnover and clinicians should keep osteoporosis in mind in gout patients.

Cathepsin Z as a novel potential biomarker for osteoporosis

Osteoporosis, one of the most prevalent chronic ageing-related bone diseases, often goes undetected until the first fragility fracture occurs, causing patient suffering and cost to health/social care services. Osteoporosis arises from imbalanced activity of osteoclasts and osteoblasts. Since these cell lineages produce the protease, cathepsin Z, the aim of this study was to investigate whether altered cathepsin Z mRNA levels are associated with osteoporosis in clinical samples. Cathepsin Z mRNA in human peripheral blood mononuclear cells was significantly differentially-expressed among non-osteoporotic controls, osteopenia and osteoporosis patients (p < 0.0001) and in female osteoporosis patients over the age of 50 years (P = 0.0016). Cathepsin Z mRNA level strongly correlated with low bone mineral density (BMD) (g/cm²), lumbar spine L2-L4 and femoral neck (T-scores) (P = 0.0149, 0.0002 and 0.0139, respectively). Importantly, cathepsin Z mRNA was significantly associated with fragility fracture in osteoporosis patients (P = 0.0018). The levels of cathepsin Z mRNA were not significantly higher in patients with chronic inflammatory disorders in these two groups compared to those without (P = 0.774 and 0.666, respectively). ROC analysis showed that cathepsin Z mRNA has strong diagnostic value for osteoporosis and osteoporotic fracture. The results show for the first time that cathepsin Z could be a future diagnostic biomarker for osteoporosis including female osteoporosis patients over the age of 50 years.

Osteoporosis in Systemic Autoinflammatory Diseases: A Case-Control Study

Objective: To assess if patients affected by systemic autoinflammatory diseases (SAIDs) present an increased risk of osteoporosis (OP). Methods: Forty adults patients referred to the Rheumatology Unit of Padova University Hospital affected by Familial Mediterranean Fever (FMF), TNF-Receptor Associated Periodic Syndrome (TRAPS), and Mevalonate Kinase Deficiency (MKD) and 40 healthy subjects were enrolled. Blood and urine samples were collected in order to define phosphocalcic metabolism, including Receptor activator of nuclear factor kappa-B ligand (RANKL) and osteoprotegerin (OPG), and among inflammatory markers serum amyloid A (SAA). Femur and lumbar dual-energy X-ray absorptiometry (DXA) scans were performed and Trabecular Bone Score (TBS) was calculated on DXA lumbar images. Results: We did not observe a statistically significant difference between Bone Mineral Density (BMD) and TBS of patients compared to controls. Also, the values of phosphocalcic metabolites in patients did not statistically differ from those in controls. However, SAA and OPG levels were significantly higher in patients compared to healthy subjects (p = 0.0244 and p = 0.0064, respectively). Conclusion: Patients of our cohort affected by FMF, TRAPS, and MKD do not present an increased risk of OP compared to the healthy controls. TBS and BMD are similar between the two groups underlining a preserved bone quality in patients. High OPG levels could suggest a protective role and a bone re-balancing action in response to an inflammatory background. Finally, it should be taken into account a modulatory role played by a pro-inflammatory cytokine such as SAA on bone homeostasis.

Insufficiency fractures: A rare cause of foot and ankle pain in three patients with rheumatoid arthritis

Insufficiency fractures are recognized but rare complications in patients with longstanding rheumatoid arthritis. Such fractures are typically solitary and are rarely seen to affect the foot and ankle. We describe 3 women with longstanding rheumatoid arthritis, treated with one, or a combination of, corticosteroids, DMARDs and anti-TNF, presenting with foot and ankle pain with no prior history of trauma. MRIs showed rare multiple florid insufficiency fractures of the foot and ankle, in 2 cases bilaterally, which were managed conservatively. These cases highlight the importance of considering insufficiency fractures in similar patients presenting with foot and ankle pain. Radiographs may fail to demonstrate these lesions, delaying diagnosis, and worsening patient outcome, therefore in such cases MRI is a valuable modality.

Male patients with rheumatoid arthritis have an increased risk of osteoporosis: Frequency and risk factors

Most previous research investigating osteoporosis in rheumatoid arthritis (RA) has focused on female patients and there is a lack of data regarding clinical characteristics of osteoporosis in male patients with RA.The aim of this study was to compare the frequency of osteoporosis between male patients with RA and healthy patients, and to identify the risk factors for osteoporosis and low bone mineral density (BMD) in male patients with RA.We conducted a retrospective, cross-sectional study including 76 South Korean male patients with RA aged over 50 years and 76 age-matched male healthy individuals. BMD was measured at the lumbar spine (L1-4) and left hip (femoral neck and total hip) using dual energy X-ray absorptiometry. Osteoporosis was defined as a T-score of ≤ -2.5 according to the World Health Organization (WHO) classification.The frequency of osteoporosis at either the spine or the hip among male patients with RA was significantly higher than that among controls (22.4% vs 10.5%, P = .049) and RA patients had a significantly lower total hip BMD than healthy individuals (0.92 ± 0.14 vs 0.96 ± 0.1 g/cm, P = .027). For male RA patients, the mean 28-joint Disease Activity Scores using erythrocyte sedimentation rate (DAS28-ESR) and body mass index (BMI) were 3.28 and 22 kg/m, respectively. In multivariable logistic regression models, BMI ≤ 22 kg/m (odds ratio = 3.43, P = .043) and DAS28-ESR > 3.2 (odds ratio = 3.85, P = .032) were independent risk factors for osteoporosis at either site in male patients with RA.Our data demonstrate that male patients with RA had a 2.1 times higher risk for osteoporosis compared with healthy individuals. This suggests that appropriate management of osteoporosis in patients with RA is crucial not only for postmenopausal women but also for men aged over 50 years, especially those with low BMI and higher disease activity.

Death effects of reveromycin A in normal and disease-associated cells of the joint

Earlier work in our laboratory demonstrated that naturally occurring reveromycin A (Rev A) causes apoptosis in osteoclasts without accompanying necrosis. Rev A death effects in both normal and diseased joint cells were investigated in this study. A dose of 10 μM Rev A did not cause apoptosis nor necrosis in monolayer chondrocytes, even at pH 6.8, a pH mimicking that of an inflamed joint. In contrast, at the acidic pH Rev A did induce significant apoptosis (fourfold increase at 48 h of treatment, P < 0.005) in normal synoviocytes without accompanying necrosis. Western blot of the normal synoviocyte proteins revealed that cytochrome c levels were not significantly changed over the time course of treatment nor did caspase 8 activity increase; therefore, Rev A appears to exert this apoptotic effect through a mechanism independent of the classical intrinsic and extrinsic pathways. Fibroblast-like synoviocytes isolated from rheumatoid arthritis patients (RAFLS) as well as normal human fibroblast-like synoviocytes (NHFLS), cells known to play key roles in arthritic joint pathology, were also subjected to Rev A treatment at both physiologic and acidic pH's. Neither apoptosis nor necrosis was induced in either RAFLS or NHFLS. Parallel mitomycin C treatment of NHFLS induced both apoptosis and necrosis. Comparative structure-activity analyses of Rev A and mitomycin C revealed that Rev A is less likely to cross the cell membrane at near neutral pH. Collectively the data reveal that a physiological dose of Rev A under acidic conditions induces normal synoviocytes to undergo apoptosis while pathologic fibroblast-like synoviocytes are resistant to apoptosis and necrosis.

Autologous minced muscle grafts improve endogenous fracture healing and muscle strength after musculoskeletal trauma

The deleterious impact of concomitant muscle injury on fracture healing and limb function is commonly considered part of the natural sequela of orthopedic trauma. Recent reports suggest that heightened inflammation in the surrounding traumatized musculature is a primary determinant of fracture healing. Relatedly, there are emerging potential therapeutic approaches for severe muscle trauma (e.g., volumetric muscle loss [VML] injury), such as autologous minced muscle grafts (1 mm3 pieces of muscle; GRAFT), that can partially prevent chronic functional deficits and appear to have an immunomodulatory effect within VML injured muscle. The primary goal of this study was to determine if repair of VML injury with GRAFT rescues impaired fracture healing and improves the strength of the traumatized muscle in a male Lewis rat model of tibia open fracture. The most salient findings of the study were: (1) tibialis anterior (TA) muscle repair with GRAFT improved endogenous healing of fractured tibia and improved the functional outcome of muscle regeneration; (2) GRAFT repair attenuated the monocyte/macrophage (CD45+CDllb+) and T lymphocyte (CD3+) response to VML injury; (3) TA muscle protein concentrations of MCP1, IL-10, and IGF-1 were augmented in a proregenerative manner by GRAFT repair; (4) VML injury concomitant with osteotomy induced a heightened systemic presence of alarmins (e.g., soluble RAGE) and leukocytes (e.g., monocytes), and depressed IGF-1 concentration, which GRAFT repair ameliorated. Collectively, these data indicate that repair of VML injury with a regenerative therapy can modulate the inflammatory and regenerative phenotype of the treated muscle and in association improve musculoskeletal healing.

Osteoblast Role in Rheumatic Diseases

Alterations in osteoblast growth, differentiation and activity play a role in the pathogenesis of several rheumatic diseases, such as rheumatoid arthritis, spondyloarthritides, osteoarthritis, and osteoporosis. In fact, in these rheumatic diseases, abnormal activity of Wnt signaling, receptor activator of nuclear factor-κB (RANK)-RANK ligand (RANKL)-osteoprotegerin (OPG) signaling, bone morphogenetic proteins (BMPs) pathway and other mechanisms have been described in osteoblasts. This review article is focused on current knowledge on the role of osteoblast dysregulation occurring in rheumatic diseases.

Inflammatory osteolysis: a conspiracy against bone

There are many causes of inflammatory osteolysis, but regardless of etiology and cellular contexts, the osteoclast is the bone-degrading cell. Thus, the impact of inflammatory cytokines on osteoclast formation and function was among the most important discoveries advancing the treatment of focal osteolysis, leading to development of therapeutic agents that either directly block the bone-resorptive cell or do so indirectly via cytokine arrest. Despite these advances, a substantial number of patients with inflammatory arthritis remain resistant to current therapies, and even effective anti-inflammatory drugs frequently do not repair damaged bone. Thus, insights into events such as those impacted by inflammasomes, which signal through cytokine-dependent and -independent mechanisms, are needed to optimize treatment of inflammatory osteolysis.

Endocrine Comorbidities in Patients with Psoriatic Arthritis: A Population-based Case-controlled Study

OBJECTIVE

To investigate endocrine comorbidities in patients with psoriatic arthritis (PsA).

METHODS

A retrospective, cross-sectional study was performed with the database of Clalit Health Services, the largest healthcare provider in Israel, between 2002 and 2014. Patients with PsA were identified and matched by age and sex to healthy controls. The following morbidities were analyzed: hypo/hyperthyroidism, hypo/hyperparathyroidism, hyperprolactinemia, Cushing disease, Addison disease, diabetes insipidus, diabetes mellitus (DM), pituitary adenoma, acromegaly, and osteoporosis. Descriptive statistics were applied. The associations between PsA and endocrine comorbidities were analyzed by univariable and multivariable analysis.

RESULTS

The study included 3161 patients with PsA, 53.4% women, mean age 58.4 ± 15.4 years, and 31,610 controls. Comparative analyses yielded higher proportion of hypothyroidism (12.7% vs 8.6%, p < 0.0001), Cushing disease (0.3% vs 0.1%, p < 0.0001), osteoporosis (13.2% vs 9.1%, p < 0.0001), and DM (27.9% vs 20.7%, p < 0.0001) in the PsA group compared with the control group. In the multivariable regression analysis, the following diseases were more frequent in the PsA group: hypothyroidism (OR 1.61, 95% CI 1.47-1.81), DM (OR 1.35, 95% CI 1.18-1.42), Cushing disease (OR 3.96, 95% CI 1.67-9.43), and osteoporosis (OR 1.56, 95% CI 1.37-1.78).

CONCLUSION

PsA is associated with a high frequency of hypothyroidism, osteoporosis, DM, and Cushing disease. Awareness of these comorbidities may help physicians provide the optimal medical care to patients with PsA.

Comorbidities in Patients with Psoriatic Arthritis

Epidemiological studies have shown that patients with psoriatic arthritis (PsA) are often affected by numerous comorbidities that carry significant morbidity and mortality. Reported comorbidities include diabetes mellitus, obesity, metabolic syndrome, cardiovascular diseases, osteoporosis, inflammatory bowel disease, autoimmune eye disease, non-alcoholic fatty liver disease, depression, and fibromyalgia. All health care providers for patients with PsA should recognize and monitor those comorbidities, as well as understand their effect on patient management to ensure an optimal clinical outcome.

Patterns and Consequences of Multimorbidity in the General Population: There is No Chronic Disease Management Without Rheumatic Disease Management

OBJECTIVE

To identify empirical model-based patterns of multimorbidity from chronic noncommunicable diseases in the general population, with a focus on the contribution of rheumatic and musculoskeletal diseases (RMDs), and to quantify their association with adverse health outcomes.

METHODS

Cross-sectional data from the Portuguese Fourth National Health Survey were analyzed (n = 23,754). Latent class analysis was used to identify patterns of coexistence of 11 chronic noncommunicable diseases (RMDs, diabetes mellitus, hypertension, chronic obstructive pulmonary disease, stroke, depression, myocardial infarction, cancer, osteoporosis, asthma, and renal failure). Based on the Outcome Measures in Rheumatology, filter 2.0, health outcomes included life impact, pathophysiologic manifestations, and resource use. We assessed the association between patterns and adverse health outcomes, through sex-, age-, and body mass index-adjusted prevalence ratios with 95% confidence intervals, obtained using Poisson regression.

RESULTS

Four patterns of chronic noncommunicable diseases co-occurrence were identified and labeled as low disease probability, cardiometabolic conditions, respiratory conditions, and RMDs and depression. RMDs were highly prevalent in patients with chronic diseases (from 38.6% in cardiometabolic conditions to 66.7% in RMDs and depression). While negative self-rated health, short-term disability, and chronic pain were more strongly associated with cardiometabolic conditions and respiratory conditions, all multimorbidity patterns were similarly associated with long-term disability, frequent health care utilization, and out-of-pocket health care expenses.

CONCLUSION

Our study emphasizes RMDs as a major presence in multimorbidity in the general population. All multimorbidity patterns were associated with a wide set of adverse health outcomes. Management strategies for the patient with chronic cardiometabolic, respiratory, or depressive conditions should also target RMDs.

The association between insulin-like growth factor 1 (IGF-1), IGF-binding proteins (IGFBPs), and the carboxyterminal propeptide of type I procollagen (PICP) in pre- and postmenopausal women with rheumatoid arthritis

OBJECTIVES

To assess the association between plasma levels of the insulin-like growth factor (IGF) system including IGF-1, IGF-binding proteins (IGFBPs) including IGFBP-1, total (t-)IGFBP-3 and functional (f-)IGFBP-3, and the carboxyterminal propeptide of type I procollagen (PICP) in pre- and postmenopausal women with rheumatoid arthritis (RA).

METHOD

Plasma concentrations of IGF-1, IGFBP-1, t-IGFBP-3, f-IGFBP-3, and PICP were measured by immunoassay.

RESULTS

No significant difference was observed in plasma IGF-1 levels between pre- and postmenopausal subjects. Plasma levels of IGFBP-1 were elevated in RA. PICP and f-IGFBP-3 were greatly affected by menopausal status. Of the three IGFBPs tested, only f-IGFBP-3 plasma levels in RA women correlated negatively with age and disease duration. A positive correlation was demonstrated between PICP and erythrocyte sedimentation rate (ESR) in RA. Moreover, there was no correlation between PICP and IGF-1 and any of the IGFBPs in RA women.

CONCLUSIONS

Considerable disruption of the IGF system in RA was found to be related to disease activity and duration. Changes in the IGF-IGFBP axis and PICP levels were different in pre- and postmenopausal women with RA. Elevated plasma PICP concentrations may indicate an increased rate of bone formation in postmenopausal RA women. Additionally, the observed changes in the IGF/IGFBP system did not affect bone formation during RA.

[Bone mineral density in patients with scleroderma systematica]

AIM

To study the frequency and magnitude of a reduction in bone mineral density (BMD) and its association with clinical parameters in patients with scleroderma systematica (SDS).

SUBJECTS AND METHODS

Fifty-six postmenopausal women aged 45-71 years (58.1±7.1 years) with a valid diagnosis of SDS and 44 age-matched healthy women were examined. Dual-energy X-ray absorptiometry (Hologic QDR 4500, Waltham, MA) was performed in all the included patients to measure BMD in the lumbar spine (L(I)-L(IV)), femoral neck, and proximal femur.

RESULTS

The patients with SDS and the healthy women showed no differences in body mass index (BMI) (24.7±4.6 and 25.7±3.5 kg/m(2), respectively) and postmenopause duration (9.6±6.4 and 9.5±7.0 years, respectively); menopause occurred earlier in the patients with SDS than in the healthy women (46.9±3.6 and 49.7±3.0 years, respectively (p<0.001). The patients with SDS versus the controls had a significantly lower BMD in the lumbar spine (0.821±0.121 and 0.861±0.092 g/cm(2); р<0.05), femoral neck (0.620±0.129 and 0.736±0.112 g/cm(2); p<0.0001), and proximal femur (0.736±0.148 and 0.884±0.124 g/cm(2); р<0.0001). Osteoporosis (OP) was detected in 29 (52%) of the 56 patients and in only 5 (11%) of the 44 control women (р<0.0001). The patients with diffuse SDS displayed a much greater reduction in BMD in all the regions than those with circumscribed SDS. BMD was significantly lower in the patients treated with glucocorticosteroids (GCS) than in the untreated ones. In the control group, BMD was associated with age, duration of menopause, and BMI. In the patients with SDS, BMD was correlated with BMI and inversely correlated with duration of menopause, and the magnitude of a BMD reduction was closely related to disease duration. The patients also showed an inverse correlation of BMD with the daily dose of GCS.

CONCLUSION

The postmenopausal women with SDS were found to have a lower BMD in 80% of cases. In this category of women, the reduction in BMD was significantly commoner and more pronounced than in the age-matched healthy women. Low BMI, diffuse SDS, disease duration, and GCS use are risk factors for reduced BMD and OP.

Comorbidities in Psoriatic Arthritis

Epidemiologic studies have shown that, in patients with psoriatic arthritis (PsA), associated comorbidities may occur more frequently than expected. This article discusses related comorbidities in patients with PsA. Identifying these comorbidities may affect the management and treatment decisions for these patients to ensure an optimal clinical outcome. All health care providers caring for patients with PsA should be aware of the relevant comorbidities and should have an understanding of how these comorbidities affect management. The common comorbidities include cardiovascular disease, metabolic syndrome, obesity, diabetes, fatty liver disease, inflammatory bowel disease, ophthalmic disease, kidney disease, osteoporosis, depression, and anxiety.

Thoracic and lumbar vertebral bone mineral density changes in a natural occurring dog model of diffuse idiopathic skeletal hyperostosis

Ankylosing spinal disorders can be associated with alterations in vertebral bone mineral density (BMD). There is however controversy about vertebral BMD in patients wuse idiopathic skeletal hyperostosis (DISH). DISH in Boxer dogs has been considered a natural occurring disease model for DISH in people. The purpose of this study was to compare vertebral BMD between Boxers with and without DISH. Fifty-nine Boxers with (n=30) or without (n=29) DISH that underwent computed tomography were included. Vertebral BMD was calculated for each thoracic and lumbar vertebra by using an earlier reported and validated protocol. For each vertebral body, a region of interest was drawn on the axial computed tomographic images at three separate locations: immediately inferior to the superior end plate, in the middle of the vertebral body, and superior to the inferior end plate. Values from the three axial slices were averaged to give a mean Hounsfield Unit value for each vertebral body. Univariate statistical analysis was performed to identify factors to be included in a multivariate model. The multivariate model including all dogs demonstrated that vertebral DISH status (Coefficient 24.63; 95% CI 16.07 to 33.19; p <0.001), lumbar vertebrae (Coefficient -17.25; 95% CI -23.42 to -11.09; p < 0.01), and to a lesser extent higher age (Coefficient -0.56; 95% CI -1.07 to -0.05; p = 0.03) were significant predictors for vertebral BMD. When the multivariate model was repeated using only dogs with DISH, vertebral DISH status (Coefficient 20.67; 95% CI, 10.98 to 30.37; p < 0.001) and lumbar anatomical region (Coefficient -38.24; 95% CI, -47.75 to -28.73; p < 0.001) were again predictors for vertebral BMD but age was not. The results of this study indicate that DISH can be associated with decreased vertebral BMD. Further studies are necessary to evaluate the clinical importance and pathophysiology of this finding.

The role of IL-1β in the bone loss during rheumatic diseases

Several inflammatory diseases have been associated with increased bone resorption and fracture rates and different studies supported the relation between inflammatory cytokines and osteoclast activity. The main factor required for osteoclast activation is the stimulation by receptor activator of nuclear factor kappa-B ligand (RANKL) expressed on osteoblasts. In this context, interleukin- (IL-) 1β, one of the most powerful proinflammatory cytokines, is a strong stimulator of in vitro and in vivo bone resorption via upregulation of RANKL that stimulates the osteoclastogenesis. The resulting effects lead to an imbalance in bone metabolism favouring bone resorption and osteoporosis. In this paper, we review the available literature on the role of IL-1β in the pathogenesis of bone loss. Furthermore, we analysed the role of IL-1β in bone resorption during rheumatic diseases and, when available, we reported the efficacy of anti-IL-1β therapy in this field.