Tumour necrosis factor-related apoptosis-inducing ligand and osteoprotegerin serum levels in psoriatic arthritis

Osteoporosis in psoriatic arthritis: Risk factors, insufficiency fractures and its association with the disease activity

OBJECTIVE

The prevalence of osteoporosis (OP) and insufficiency fractures in psoriatic arthritis (PsA) remains controversial. The aim of this study was to describe the prevalence of OP and insufficiency fractures in a representative cohort of patients with PsA, and to analyse its association with general risk factors and characteristics of the psoriatic disease in our geographical area.

METHODS

Multi-centric, descriptive study of patients with PsA. We recorded clinical characteristics, as well as protective and risk factors for OP and insufficiency fractures. Hip and lumbar densitometry and lateral X-ray of the spine were evaluated. Descriptive statistics for OP and risk factors were calculated. The patients with OP were compared to those without by univariate analyses, and results were adjusted by age and sex. The association of OP and fractures with clinical characteristics was analysed by logistic regression.

RESULTS

166 patients (50 men; 116 women) were included. OP was present in 26.5%, and it was more frequent in women and patients above 50 years old. Insufficiency fractures occurred in 5.4% of the total sample. In the logistic regression, OP was associated with age over 50 [OR 3.7; 95% CI (1.2-11.6); p=.02]. No association with clinical parameters was found. The most frequent risk factors among patients with OP were vitamin D insufficiency, sedentary behaviour, low calcium intake, and active smoking. In the logistic regression, OP was associated with early menopause [OR 11.7; 95% CI (1.29-106.0); p=.029] and sedentary behaviour [OR 2.3; 95% CI (1.0-5.2); p=.049].

CONCLUSIONS

In patients with PsA, OP is more frequent in women and patients over 50 years old. A sedentary lifestyle and early menopause may add extra risk for OP. Type, duration disease, and treatments are not associated with OP or insufficiency fractures.

Incidence of Pulmonary Arterial Hypertension in Patients with Psoriasis: A Retrospective Cohort Study

CONTEXT

Inflammatory signaling may play an important role in the pathogenesis of pulmonary arterial hypertension (PAH).

OBJECTIVE

To assess the incidence of PAH in patients with mild and severe psoriasis compared with their respective controls.

DESIGN

From January 2004 to November 2012, we performed a retrospective cohort study of patients with psoriasis in the Kaiser Permanente Southern California Health Plan. Patients with an International Classification of Diseases, Ninth Revision Clinical Modification diagnostic code for psoriasis (696.1) or psoriatic arthritis (696.0) without a prior diagnosis of primary PAH (416.0) or secondary PAH (416.8) were eligible for inclusion. Patients who had never received a diagnosis of psoriasis were frequency-matched by age, sex, and race to form the control cohorts.

MAIN OUTCOME MEASURES

Incidence of PAH in patients with psoriasis compared with matched controls.

RESULTS

There were 10,115 patients with mild psoriasis, 3821 with severe psoriasis, and 69,360 matched controls. On multivariable analysis, there was a significantly increased risk of PAH developing in the severe psoriasis cohort vs their controls (hazard ratio = 1.46, 95% confidence interval = 1.09-1.94).

CONCLUSION

The systemic inflammatory process underlying psoriasis may be a cause for an increased risk of PAH, but there are numerous secondary causes of PAH, some of which were not accounted for in our study. Further prospective, randomized controlled trials are necessary to establish psoriasis as a risk factor for PAH.

Bone mineral density is lower in male than female patients with plaque-type psoriasis in Iran

Background

There are many similarities with regard to contributing cytokines in patients with psoriasis and osteoporosis. A theory of probable relationship between these two entities has been proposed but there is no concordant consensus. The aim of this study was to evaluate bone mineral density (BMD) in patients with psoriasis.

Method and materials

This cross-sectional study of BMD was conducted with 64 eligible patients with psoriasis who were referred to the dermatology clinic of Razi hospital in Tehran, Iran in between 2011 and 2012.

Results

The mean T score of femoral neck was –1.17 and –0.49 in men and women, respectively, which was statistically significant (p = .047). The mean T score of the lumbar spine was –0.93 and –0.30 in men and women, respectively, but not statistically significant (p = .058). In total except with the exclusion of the study site (femur or lumbar), men and women did not have a statistically significant difference with regard to osteoporosis or osteopenia in BMD (p = .114). The Pearson correlation coefficient demonstrated a moderate inverse relationship between age and T score of the femoral neck and lumbar spine (r = –0.419 and –.406, respectively), which was statistically significant (p = .001). Although there was no statistically significant relationship between the Psoriasis Area and Severity Index (PASI) and T scores of the femoral neck (p = .596), a positive and weak correlation was observed between the PASI and T scores for the lumbar spine, which was statistically significant (r = 0.269; p = .03).

Conclusion

Patients with psoriasis had decreased bone density, which was more significant in men. Prevalence of osteoporosis showed no statistically significant difference when compared with the healthy population in Iran.

Stage-dependent effects of exogenous TRAIL on atherogenesis: role of ER stress-mediated sensitization of macrophage apoptosis

Deletion of the gene of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in apolipoprotein E-deficient (ApoE-/-) mice increased atherosclerosis. However, the effect of TRAIL at a supra-physiological level on early atherogenesis is unknown. ApoE-/- mice were divided into Early (high-fat diet with concomitant TRAIL treatment for 4 weeks) and Late (high-fat diet for 16 weeks with TRAIL being given during the last 4 weeks) groups. It was found that TRAIL stimulated atherogenesis in the Early group but not in the Late group. TRAIL did not change the intra-plaque macrophage content in Early group, but decreased it in the Late group. In cultured macrophages, induction of endoplasmic reticulum (ER) stress increased death receptor 5 (DR5) expression and TRAIL-induced apoptosis, which were mediated by the transcription factor CCAAT/enhancer-binding protein homologous protein (CHOP). The expression levels of CHOP, 78 kDa glucose-regulated protein (GRP78) and DR5 were all elevated in the Late group. TRAIL treatment in vivo also increased intra-plaque apoptotic only in Late lesions. Moreover, the chemical chaperone 4-phenylbutyrate blocked the development of ER stress and upregulation of DR5 in Late lesions in vivo. In conclusion, TRAIL at a supra-physiological level has a stimulatory effect on early atherogenesis, but not in the advanced lesions. The differential effects of TRAIL may be related to differences in ER stress, DR5 expression, and the sensitivity of macrophage apoptosis in response to TRAIL in early versus advanced lesions. The results presented here raise the possibility that treatment with exogenous TRAIL as a therapeutic agent may be detrimental in patients with increased risk of atherosclerosis.

Expression of osteoprotegerin and its ligands, RANKL and TRAIL, in rheumatoid arthritis

Osteoprotegerin (OPG), receptor activator of nuclear factor-ΚB ligand (RANKL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) have been involved in rheumatoid arthritis (RA) pathophysiology. In this study, we assessed messenger RNA (mRNA) expression of these molecules by qPCR in peripheral blood from 26 patients with RA (12 of them with ischemic heart disease –IHD) and 10 healthy controls. Correlation coefficients between OPG, RANKL and TRAIL expression levels in RA patients and their clinical and demographic characteristics were also evaluated. Whereas OPG and OPG/TRAIL ratio expression were significantly increased in RA patients compared to controls (fold change = 1.79, p = 0.013 and 2.07, p = 0.030, respectively), RANKL/OPG ratio was significantly decreased (fold change = 0.50, p = 0.020). No significant differences were found between patients and controls in RANKL and TRAIL expression. Interestingly, TRAIL expression was significantly higher in RA patients with IHD compared to those without IHD (fold change = 1.46, p = 0.033). Moreover, biologic disease-modifying antirheumatic drugs (DMARDs) significantly decreased RANKL expression in RA patients (p = 0.016). Our study supports an important role of OPG and TRAIL in RA. Furthermore, it highlights an effect of biologic DMARDs in the modulation of RANKL.

Evaluation of Serum Fetuin-A and Osteoprotegerin Levels in Patients with Psoriasis

Psoriasis patients are determined to have a high ratio of coronary artery calcification. Fetuin-A and osteoprotegerin are systemic calcification inhibitors and related to vascular calcification and cardiovascular mortality. In this study we investigated the relationship between fetuin-A and osteoprotegerin levels in psoriasis patients. The study included 40 healthy volunteers and 40 psoriasis patients. Venous blood were collected from healthy volunteers and psoriasis patients in order to search the fetuin-A and osteoprotegerin levels. Disease severity were grouped as mild, moderate and severe according to psoriasis area and severity index (PASI). The relationship between fetuin-A and osteoprotegerin levels and clinical features as sex, PASI and presence of psoriatic arthritis were analyzed. Fetuin-A levels in psoriasis patients were statistically lower than the control group (p < 0.001). In serum osteoprotegerin levels, no statistically significant difference was found in two groups (p > 0.05). Serum fetuin-A and osteoprotegerin level differences were not statistically significant between patients with psoriatic arthritis history and those without. When we grouped patients in respect of their sexes fetuin-A and osteoprotegerin levels of males and females were not significantly different (p > 0.05). No correlation was detected between the ages and PASI scores and the fetuin-A and osteoprotegerin levels of patients. As a result fetuin-A levels in psoriasis patients are found to be low but not related to disease severity. In the light of our results we concluded that fetuin-A may have a role in psoriasis pathogenesis and may contribute to the calcification process developed in psoriasis.

Psoriasis: new comorbidities

Psoriasis is a chronic inflammatory disease associated with several comorbidities. A few decades ago, it was considered an exclusive skin disease but today it is considered a multisystem disease. It is believed that 73% of psoriasis patients have at least one comorbidity. Studies have demonstrated the association of psoriasis with inflammatory bowel disease, uveitis, psychiatric disorders, metabolic syndrome and its components and cardiovascular diseases. The systemic inflammatory state seems to be the common denominator for all these comorbidities. This work aims at presenting a review of the current literature on some new comorbidities that are associated with psoriasis as osteoporosis, obstructive sleep apnea and chronic obstructive pulmonary disease. While there is still controversy, many studies already point to a possible bone involvement in patients with psoriasis, especially in the male group, generally less affected by osteoporosis. Psoriasis and chronic obstructive pulmonary disease present some risk factors in common as obesity, smoking and physical inactivity. Besides, both diseases are associated with the metabolic syndrome. These factors could be potential confounders in the association of the two diseases. Further prospective studies with control of those potential confounders should be developed in an attempt to establish causality. Existing data in the literature suggest that there is an association between obstructive sleep apnea and psoriasis, but studies performed until now have involved few patients and had a short follow-up period. It is, therefore, premature to assert that there is indeed a correlation between these two diseases.

Soluble TRAIL Concentration in Serum Is Elevated in People with Hypercholesterolemia

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a multi-functional cytokine, which is involved in the pathophysiological processes of cardiovascular and metabolic diseases. Previously, we demonstrated that TRAIL stimulated lipid uptake and foam cell formation in macrophages in vitro. Several clinical studies have suggested that the serum concentration of TRAIL may be increased in humans with elevated blood cholesterol; however, the current data appear to be inconclusive in this regard. In the present study, we examined the relationships between the serum TRAIL concentration and cholesterol levels in 352 generally healthy subjects undergoing the routine annual health check. We showed that there were significant correlations between TRAIL concentration and levels of total and low-density lipoprotein cholesterols. The level of TRAIL was significantly elevated in subjects with hypercholesterolemia, although this relationship might be also associated with changes of other metabolic factors. Moreover, we showed that the level of blood cholesterol was significantly higher in subjects in the upper quartile of serum TRAIL. In conclusion, our data demonstrate that the serum TRAIL concentration is elevated in people with hypercholesterolemia.

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.

Therapeutic applications of TRAIL receptor agonists in cancer and beyond

TRAIL/Apo-2L is a member of the TNF superfamily first described as an apoptosis-inducing cytokine in 1995. Similar to TNF and Fas ligand, TRAIL induces apoptosis in caspase-dependent manner following TRAIL death receptor trimerization. Because tumor cells were shown to be particularly sensitive to this cytokine while normal cells/tissues proved to be resistant along with being able to synthesize and release TRAIL, it was rapidly appreciated that TRAIL likely served as one of our major physiologic weapons against cancer. In line with this, a number of research laboratories and pharmaceutical companies have attempted to exploit the ability of TRAIL to kill cancer cells by developing recombinant forms of TRAIL or TRAIL receptor agonists (e.g., receptor-specific mAb) for therapeutic purposes. In this review article we will describe the biochemical pathways used by TRAIL to induce different cell death programs. We will also summarize the clinical trials related to this pathway and discuss possible novel uses of TRAIL-related therapies. In recent years, the physiological importance of TRAIL has expanded beyond being a tumoricidal molecule to one critical for a number of clinical settings - ranging from infectious disease and autoimmunity to cardiovascular anomalies. We will also highlight some of these conditions where modulation of the TRAIL/TRAIL receptor system may be targeted in the future.

Genetic, Epigenetic and Pharmacogenetic Aspects of Psoriasis and Psoriatic Arthritis

There is a strong familial component to psoriatic disease as well as a complex array of genetic, immunologic, and environmental factors. The dominant genetic effect is located on chromosome 6p21.3 within the major histocompatibility complex region, accounting for one-third of genetic contribution. Genome-wide association studies (GWAS) identified additional genes, including skin barrier function, innate immune response, and adaptive immune response genes. To better understand disease susceptibility and progression requires replication in larger cohorts, fine-mapping efforts, new technologies, and functional studies of genetic variants, gene-gene interactions and gene-environmental interactions. New technologies available include next-generation sequencing, copy number variation analysis, and epigenetics.

Tumor necrosis factor-related apoptosis-inducing ligand induces the expression of proinflammatory cytokines in macrophages and re-educates tumor-associated macrophages to an antitumor phenotype

This study reveals that tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) induces expression of IL-1β, IL-6, and tumor necrosis factor α in macrophages, especially in tumor-associated macrophages (TAMs). TRAIL re-educates TAMs to an M1-like phenotype and induces their cytotoxicity to tumor cells. This study provides new evidence for TRAIL in immune regulation of macrophages and sheds light on TRAIL-based antitumor therapy in human patients.

Tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) is a promising candidate for cancer therapy, because it can induce apoptosis in various tumor cells but not in most normal cells. Although it is well known that TRAIL and its receptors are expressed in many types of normal cells, including immune cells, their immunological effects and regulatory mechanisms are still obscure. In the present study, we demonstrated that TRAIL affected the activity of NF-κB (nuclear factor-κB) and the expression of its downstream proinflammatory cytokines IL-1β (interleukin-1β), IL-6, and tumor necrosis factor α in macrophages. TRAIL also induced microRNA-146a (miR-146a) expression in an NF-κB–dependent manner. As a result, miR-146a was involved as a negative-feedback regulator in the down-regulation of proinflammatory cytokine expression. In addition, the suppression of histone deacetylase (HDAC) activities by trichostatin A improved miR-146a expression due to the up-regulation of the DNA-binding activity of NF-κB at the miR-146a promoter in TRAIL-induced macrophages, suggesting that histone acetylation was involved in the suppression of miR-146a expression. Further investigation revealed that the HDAC subtype HDAC1 directly regulated the expression of miR-146a in TRAIL-stimulated macrophages. Finally, the TRAIL-sensitive human non small cell lung carcinoma cell line NCI-H460 was used to elucidate the physiological significance of TRAIL with respect to tumor-associated macrophages (TAMs). We demonstrated that TRAIL re-educated TAMs to an M1-like phenotype and induced cytotoxic effects in the tumor cells. These data provide new evidence for TRAIL in the immune regulation of macrophages and may shed light on TRAIL-based antitumor therapy in human patients.

Psoriasis: classical and emerging comorbidities

Psoriasis is a chronic inflammatory systemic disease. Evidence shows an association of psoriasis with arthritis, depression, inflammatory bowel disease and cardiovascular diseases. Recently, several other comorbid conditions have been proposed as related to the chronic inflammatory status of psoriasis. The understanding of these conditions and their treatments will certainly lead to better management of the disease. The present article aims to synthesize the knowledge in the literature about the classical and emerging comorbidities related to psoriasis.

The Assessment of Selected Bone and Cartilage Biomarkers in Psoriatic Patients from Poland

Background. Psoriasis is an inflammatory disease in which joints involvement may be insidious and difficult to detect. Bone and cartilage biomarkers may be helpful in screening patients with psoriasis for psoriatic arthritis (PsA). Objectives. To assess bone and cartilage serum biomarkers in psoriasis. Methods. The study was conducted in 2014 and included 61 psoriatic patients and 30 healthy individuals. In both groups, the serum concentrations of soluble receptor activator of nuclear factor-κB ligand (sRANKL), cartilage oligomeric matrix protein (COMP), osteoprotegerin (OPG), and interleukin-20 (IL-20) were examined. Severity of skin lesions was assessed by Psoriasis Area and Severity Index (PASI), body surface area (BSA), and Physician Global Assessment (PGA) scores. Results. The duration of psoriasis was from 1 year to 45 years. 22 patients suffered from concomitant PsA. The mean value of PASI was 23.1 ± 12.0 and BSA was 27.6 ± 20.6%. COMP, OPG, and IL-20 concentrations in psoriatic patients were significantly higher than in the control group. OPG/sRANKL ratio was significantly lower in PsA patients than in psoriatic patients without arthritis. Conclusions. Results of the conducted study suggest that COMP, OPG, IL-20, and OPG/sRANKL ratio may appear useful biomarkers of bone and cartilage involvement in psoriasis.

Tumor necrosis factor-related apoptosis-inducing ligand in vascular inflammation and atherosclerosis: a protector or culprit?

In addition to inducing tumor cell apoptosis, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) shows broad biological functions both in vitro and in vivo. TRAIL gene deletion enhanced atherogenesis in hyperlipidemic mice, supporting that endogenous TRAIL has protective actions in maintaining blood vessel homeostasis and repressing atherosclerosis. The mechanisms of this beneficial effect are not understood. It remains to be determined whether the athero-protective action of TRAIL is via direct impacts on residential vascular cells or indirectly by modulating systemic immune functions. However, in vitro experiments indicate that excessive TRAIL may stimulate endothelial cell apoptosis, smooth muscle proliferation and migration, and inflammatory responses. Moreover, TRAIL can stimulate lipid uptake and foam cell formation in cultured macrophages. Here we provide a critical review on the potential relationships between TRAIL and atherosclerosis. We propose that increased TRAIL production may also have potential detrimental effects on vascular inflammation and atherosclerosis. Further in vivo experiments are warranted to elucidate the effects of exogenous TRAIL on atherogenesis.

Serum soluble bone turnover biomarkers in psoriatic arthritis and psoriatic spondyloarthropathy

Because psoriatic arthritis (PsA) is an inflammatory disease of joints, serum soluble biomarkers specific for chronic joint and bone inflammation may predict future disease severity and response to therapy, thereby informing stratified medicine approaches. The objectives of our systematic review were to determine whether serum soluble bone and cartilage turnover biomarkers are (1) associated with PsA or psoriatic spondyloarthropathy; and (2) associated with disease activity, disease severity, or clinical phenotype. Ten studies met eligibility criteria. Matrix metalloproteinase (MMP)-3, Dickkopf (DKK)-1, macrophage colony-stimulating factor (M-CSF), crosslinked telopeptide of collagen-1, and tumor necrosis factor-related apoptosis-inducing ligand were associated with PsA, with equivocal results for osteoprotegerin (OPG) and bone alkaline phosphatase (ALP). MMP-3, DKK-1, M-CSF, CPII:C2C (ratio of cartilage degradation vs byproduct formation), and possibly OPG were associated with PsA independently of psoriasis. C1-2C (a neoepitope released when type 2 cartilage is degraded by collagenases) was associated with both tender and swollen joint counts, and bone morphogenetic protein-4 with patient global assessment of disease, pain score, and the Bath Ankylosing Spondylitis Disease Activity Index. Bone ALP was associated with disease activity. M-CSF and receptor activator of nuclear factor-κB ligand were associated with several plain radiographic features. No studies have investigated biomarker associations specifically with axial PsA.

Osteoblasts display different responsiveness to TRAIL-induced apoptosis during their differentiation process

Apoptosis can occur throughout the life span of osteoblasts (OBs), beginning from the early stages of differentiation and continuing throughout all stages of their working life. Here, we investigated the effects of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) on normal human OBs showing for the first time that the expression of TRAIL receptors is modulated during OB differentiation. In particular, the TRAIL receptor ratio was in favor of the deaths because of the low expression of DcR2 in undifferentiated OBs, differently it was shifted toward the decoys in differentiated ones. Undifferentiated OBs treated with TRAIL showed reduced cell viability, whereas differentiated OBs displayed TRAIL resistance. The OB sensitiveness to TRAIL was due to the up-regulation of DR5 and the down-regulation of DcR2. The main death receptor involved in TRAIL-reduced OB viability was DR5 as demonstrated by the rescue of cell viability observed in the presence of anti-DR5 neutralizing antibody. Besides the ratio of TRAIL receptors, the sensitivity of undifferentiated OBs to TRAIL-cytotoxic effect was also associated with low mRNA levels of intracellular anti-apoptotic proteins, such as cFLIP, the activation of caspase-8 and -3, as well as the DNA fragmentation. This study suggests that apoptotic effect exerted by TRAIL/TRAIL-receptor system on normal human OB is strictly dependent upon cell differentiation status.

Psoriasis and bone mineral density: implications for long-term patients

Psoriasis is a chronic inflammatory disease associated with several comorbidities. Osteoporosis is defined as a reduction in bone mineral density with impaired bone microarchitecture. Several mechanisms may be implicated as a possible cause for the association between psoriasis and osteoporosis, such as systemic inflammation, anti-psoriatic drug intake and joint dysfunction for psoriatic arthritis (PsA). The aim of the present study was to assess bone mineral density (BMD) in patients with psoriasis, correlating the prevalence of osteopenia/osteoporosis with Psoriasis Area and Severity Index (PASI) score, mean duration of psoriatic disease, PsA and previous treatments for psoriasis. Forty-three consecutive patients with psoriasis, 19 of whom were affected by the arthropathic form, were enrolled. We evaluated the severity of psoriasis as measured by PASI score, the CASPAR criteria and ultrasounds of the joints to verify the diagnosis of PsA and the age of psoriasis onset to estimate mean disease duration. Patients underwent a bone density scan of the lumbar spine and femoral neck by dual-energy X-ray absorptiometry to measure BMD. Patients with osteopenia/osteoporosis showed a statistically significant longer average duration of psoriatic disease (17 years), compared to patients affected by psoriasis with normal T-score (8.8 years) (P = 0.04). The linear logistic regression confirms a significant relation between mean psoriatic disease duration and BMD alterations (P = 0.04). Our results suggest the necessity of an early diagnostic evaluation of bone metabolism in patients with psoriasis, especially if characterized by longer disease duration.

TRAIL/DR5 signaling promotes macrophage foam cell formation by modulating scavenger receptor expression

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L) has been shown to have protective effects against atherosclerosis. However, whether TRAIL has any effects on expression of macrophage scavenger receptors and lipid uptake has not yet been studied. Macrophage lines RAW264.7 and THP-1, and mouse primary peritoneal macrophages, were cultured in vitro and treated with recombinant human TRAIL. Real-time PCR and western blot were performed to measure mRNA and protein expressions. Foam cell formation was assessed by internalization of acetylated and oxidized low-density lipoproteins (LDL). Apoptosis was measured by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. We found that TRAIL treatment increased expression of scavenger receptor (SR)-AI and SR-BI in a time- and dose-dependent manner, and this effect was accompanied by increased foam cell formation. These effects of TRAIL were abolished by a TRAIL neutralizing antibody or in DR5 receptor-deficient macrophages. The increased LDL uptake by TRAIL was blocked by SR-AI gene silencing or the SR-AI inhibitor poly(I:C), while SR-BI blockade with BLT-1 had no effect. TRAIL-induced SR-AI expression was blocked by the inhibitor of p38 mitogen-activated protein kinase, but not by inhibitors of ERK1/2 or JNK. TRAIL also induced apoptosis in macrophages. In contrast to macrophages, TRAIL showed little effects on SR expression or apoptosis in vascular smooth muscle cells. In conclusion, our results demonstrate that TRAIL promotes macrophage lipid uptake via SR-AI upregulation through activation of the p38 pathway.

Aortic valvular interstitial cells apoptosis and calcification are mediated by TNF-related apoptosis-inducing ligand

BACKGROUND/OBJECTIVES

Calcific aortic valvular disease (CAVD) is an actively regulated process characterized by the activation of specific osteogenic signaling pathways and apoptosis. We evaluated the involvement in CAVD of the TNF-related apoptosis-inducing ligand (TRAIL), an apoptotic molecule which induces apoptosis by interacting with the death receptor (DR)-4 and DR5, and whose activity is modulated by the decoy receptor (DcR)-1 and DcR2.

METHODS

Sections of calcific and normal aortic valves, obtained at surgery time, were subjected to immunohistochemistry and confocal microscopy for TRAIL immunostaining. Valvular interstitial cells (VICs) isolated from calcific (C-VICs) and normal (N-VICs) aortic valves were investigated for the gene and protein expression of TRAIL receptors. Cell viability was assayed by MTT. Von Kossa staining was performed to verify C-VIC ability to produce mineralized nodules. TRAIL serum levels were detected by ELISA.

RESULTS

Higher levels of TRAIL were detected in calcific aortic valves and in sera from the same patients respect to controls. C-VICs express significantly higher mRNA and protein levels of DR4, DR5, DcR1, DcR2 and Runx2 compared to N-VICs. C-VICs and N-VICs, cultured in osteogenic medium, express significantly higher mRNA levels of DR4, Runx2 and Osteocalcin compared to baseline. C-VICs and N-VICs were sensitive to TRAIL-apoptotic effect at baseline and after osteogenic differentiation, as demonstrated by MTT assay and caspase-3 activation. TRAIL enhanced mineralized matrix nodule synthesis by C-VICs cultured in osteogenic medium.

CONCLUSIONS

TRAIL is characteristically present within calcific aortic valves, and mediates the calcification of aortic valve interstitial cells in culture through mechanism involving apoptosis.

Association between osteoporosis and psoriasis: results from the Longitudinal Health Insurance Database in Taiwan

This population-based analysis explored the association between osteoporosis and a previous diagnosis of psoriasis. We found that the adjusted odds ratio (OR) of having been previously diagnosed with psoriasis for subjects with osteoporosis was 1.65 (95 % confidence interval [CI], 1.42-1.94) when compared to controls.

INTRODUCTION

Although previous studies have investigated this association between psoriasis and osteoporosis, significant controversy remains regarding its presence. Therefore, this study set out to explore the association between osteoporosis and a previous diagnosis of psoriasis through a population-based case-control study in Taiwan.

METHODS

We identified 17,507 cases with a diagnosis of osteoporosis and randomly extracted 52,521 controls without a history of osteoporosis. We used conditional logistic regression analyses to calculate the OR for having been previously diagnosed with psoriasis.

RESULTS

Subjects with osteoporosis had a significantly higher prevalence of previously diagnosed psoriasis (1.50 % vs. 0.87 %, p < 0.001) compared to controls. Conditional logistic regression analysis revealed that the OR of having been previously diagnosed with psoriasis for subjects with osteoporosis was 1.65 (95 % CI, 1.42-1.94) when compared to controls after adjusting for monthly income, hypertension, diabetes, coronary heart disease, hyperlipidemia, rheumatoid arthritis, stroke, renal disease, Parkinson's disease, hyperthyroidism, chronic hepatopathy, Cushing's syndrome, malabsorption, tobacco use disorder, obesity, alcohol abuse/alcohol dependence syndrome, the use of SSRIs, and the use of systemic glucocorticoids. Furthermore, osteoporosis was significantly associated with a previous diagnosis of psoriasis in both sexes; the adjusted OR of prior psoriasis for cases when compared to controls was 1.52 (95 % CI, 1.16-1.99) and 1.73 (95 % CI, 1.44-2.13) for males and females, respectively. We also found that the adjusted OR of prior severe psoriasis for cases was 1.96 (95 % CI, 1.37-2.81) that of controls.

CONCLUSIONS

This investigation succeeded in detecting an association between osteoporosis and prior psoriasis among both men and women.

C-Reactive protein downregulates TRAIL expression in human peripheral monocytes via an Egr-1-dependent pathway

PURPOSE

To investigate the potential link between C-reactive protein (CRP), a known biomarker of acute and chronic inflammation, and TRAIL, a cytokine which plays a key role in the immune-surveillance against tumors.

EXPERIMENTAL DESIGN

Primary normal peripheral blood mononuclear cell (PBMC) and CD14(+) monocytes were exposed to recombinant CRP (1-10 μmol/L). TRAIL expression was analyzed by ELISA and/or by quantitative real-time PCR (qRT-PCR). In parallel, the potential role of the transcription factor Egr-1 was investigated by analyzing its modulation in response to CRP and by transfection experiments.

RESULTS

In vitro CRP exposure induced downregulation of TRAIL expression, both at the mRNA and protein level, in unfractionated PBMC and in purified CD14(+) monocytes. TRAIL downregulation was not due to a specific toxicity or to contaminating lipopolysaccharide (LPS), as shown by the lack of induction of monocyte apoptosis and by the inability of the inhibitor of LPS polymyxin B to interfere with CRP activity. Of note, CRP downregulated TRAIL expression/release in CD14(+) monocytes also in response to IFN-α, the most potent inducer of TRAIL. At the molecular level, the downmodulation of TRAIL by CRP was accompanied by a significant increase of Egr-1. Consistently, Egr-1 overexpression reduced the baseline levels of TRAIL mRNA, whereas knocking down Egr-1 counteracted the ability of CRP to downregulate TRAIL.

CONCLUSIONS

Our findings suggest that a chronic elevation of CRP, which occurs during systemic inflammation and often in patients with cancer, might contribute to promote cancer development and/or progression by downregulating TRAIL in immune cells.

Circulating TRAIL shows a significant post-partum decline associated to stressful conditions

Background

Since circulating levels of TNF-related apoptosis inducing ligand (TRAIL) may be important in the physiopathology of pregnancy, we tested the hypothesis that TRAIL levels change at delivery in response to stressful conditions.

Methods/Principal Findings

We conducted a longitudinal study in a cohort of 73 women examined at week 12, week 16, delivery and in the corresponding cord blood (CB). Serum TRAIL was assessed in relationship with maternal characteristics and to biochemical parameters. TRAIL did not vary between 12 (67.6±27.6 pg/ml, means±SD) and 16 (64.0±16.2 pg/ml) weeks' gestation, while displaying a significant decline after partum (49.3±26.4 pg/ml). Using a cut-off decline >20 pg/ml between week 12 and delivery, the subset of women with the higher decline of circulating TRAIL (41.7%) showed the following characteristics: i) nullipara, ii) higher age, iii) operational vaginal delivery or urgent CS, iv) did not receive analgesia during labor, v) induced labor. CB TRAIL was significantly higher (131.6±52 pg/ml) with respect to the corresponding maternal TRAIL, and the variables significantly associated with the first quartile of CB TRAIL (<90 pg/ml) were higher pre-pregnancy BMI, induction of labor and fetal distress. With respect to the biochemical parameters, maternal TRAIL at delivery showed an inverse correlation with C-reactive protein (CRP), total cortisol, glycemia and insulin at bivariate analysis, but only with CRP at multivariate analysis.

Conclusions

Stressful partum conditions and elevated CRP levels are associated with a decrease of circulating TRAIL.

Distinct impacts of syndesmophyte formation on male and female patients with ankylosing spondylitis

AIM

Ankylosing spondylitis (AS), a chronic inflammatory autoimmune disease, mainly affects the axial skeleton, leading to sacroiliitis and rigidity of the spine. Both spinal rigidity and syndesmophyte development can affect bone formation and resorption. In addition, inflammatory cytokines and cell adhesion molecules are correlated with bone metabolism. The aim of this study was to investigate the effects of gender difference and syndesmophyte formation on cytokines, adhesion molecules and bone metabolism markers in AS patients.

METHOD

Eighty-seven AS patients (68 males, 19 females) were enrolled in this study. Electrochemiluminescence immunoassay and enzyme-linked immunosorbent assay were performed to measure studied parameters.

RESULTS

Regarding gender, the serum levels of C-terminal crosslinking telopeptide of type I collagen (CTX), vascular endothelial growth factor, soluble vascular cell adhesion molecule-1, tumor necrosis factor alpha and interleukin (IL)-18 in male patients were all significantly higher than those in female patients. The serum levels of osteocalcin and type I procollagen N-terminal propeptide showed downward trends, whereas CTX and parathyroid hormone concentrations were remarkably lower and IL-18 levels were significantly higher in male AS patients with syndesmophytes compared to those without syndesmophytes. In female patients, CTX and IL-6 levels in those with syndesmophytes were significantly higher than in those without syndesmophytes. Cytokines, adhesion molecules and bone metabolism markers were all positively related with syndesmophyte formation and gender differences.

CONCLUSION

AS patients with syndesmophytes experienced imbalance of bone metabolism due to inflammatory cytokine release. Male AS patients had high levels of bone resorption markers, cytokines and adhesion molecules, reflecting a disorder of bone metabolism.

Osteoporosis in psoriatic arthritis: is there any?

AIMS

Although considered as a feature of inflammatory rheumatic diseases, there is a lot of controversy around low bone mass in patients with psoriatic arthritis. The aim of this cross-sectional study was to analyze bone mineral density in patients with psoriatic arthritis, as well as to investigate its possible association with some measures of disease activity and functional capacity.

SUBJECTS AND METHODS

Sixty-nine patients with established psoriatic arthritis (mean age 56.20 ± 12.23 years) and who have not been treated with specific antiosteoporotic drugs were recruited from the out-patient clinic database. Bone mineral density was measured by dual-energy X-ray absorptiometry at the lumbar spine and at the left hip. Disease activity measures included: duration of morning stiffness, tender and swollen joint count, patient's and physician's global assessment, presence of dactylitis and enthesitis, ESR, CRP and Disease Activity Score 28. Health Assessment Questionnaire was used to assess functional status.

RESULTS

According to WHO definition, spinal osteoporosis was found in 7.2% of patients, total hip osteoporosis in 1.4% of patients and femoral neck osteoporosis in 2.9% of patients. There was no significant association of any of the measures of disease activity with BMD at any site. Higher HAQ scores were associated with lower total hip BMD.

CONCLUSIONS

In our sample of patients with psoriatic arthritis we did not find increased prevalence of osteoporosis. There was no association of BMD with indices of disease activity, while negative correlation was found between HAQ and total hip BMD.

Assessment of osteoporosis in psoriasis with and without arthritis: correlation with disease severity

BACKGROUND

The most frequent extracutaneous association with psoriasis is arthritis. Because proinflammatory cytokines are increased in psoriasis, patients with this disease may be more prone to osteoporosis than the healthy individuals.

METHODS

We evaluated 50 patients with psoriasis, with or without psoriatic arthritis (PsA), for the presence and degree of osteoporosis by performing dual energy x-ray absorptiometry (DEXA) and obtaining serum osteoprotegrin (OPG) levels. In addition, we correlated these results with the extent of skin and joint disease. Psoriasis area and severity index (PASI) was determined in all 50 patients with psoriasis, and total joint score (TJS) was recorded in the 16 patients who also had PsA. Results of DEXA and serum OPG were also obtained for 20 healthy individuals who served as controls.

RESULTS

Osteoprotegrin level was significantly increased in psoriasis patients (with or without PsA) vs. controls. However, DEXA revealed that PsA patients had a higher degree of osteoporosis in the femur neck and wrist. In PsA patients, TJS correlated positively with both disease duration and PASI but correlated negatively with Z score of the femur.

CONCLUSION

Psoriasis patients with or without arthritis may suffer from osteoporosis as evidenced by significantly increased serum OPG. Prolonged and extensive cutaneous disease is an important risk factor for the development and severity of PsA. Patients with a greater number of affected joints are at higher risk of osteoporosis.

Bone mineral density and body composition in postmenopausal women with psoriasis and psoriatic arthritis

Introduction

The aim of the present study was to compare bone mineral density (BMD) and body composition (BC) measurements as well as identify risk factors for low BMD and osteoporotic fractures in postmenopausal women with psoriasis (Ps) and psoriatic arthritis (PsA).

Methods

A cross-sectional study was carried out in 45 PsA women, 52 Ps women and 98 healthy female controls (HC). Clinical risk factors for low bone density and osteoporotic fracture were evaluated by a specific questionnaire. An X-ray absorptiometry (DXA) at the lumbar spine, total femur and total body was performed on all patients. Skin and joint outcomes were measured by specific tools (PASI, HAQ and DAS28). Morphometric vertebral fractures were evaluated by lumbar and thoracic spine X-ray, according to Genant's method.

Results

There were no significant differences in age, body mass index (BMI), total lean mass and bone mineral density among the groups. However, the PsA group had a significantly higher body fat percentage (BF%) than the Ps and HC groups. Osteoporotic fractures were more frequently observed in PsA and Ps groups than in the HC group (P = 0.01). Recurrent falls and a longer duration of disease increased the risk of fracture (odds ratio (OR) = 18.3 and 1.08, respectively) in the PsA group (P = 0.02). Disability was the main factor related to osteoporotic fracture in the Ps group (odds ratio (OR) = 11.1) (P = 0.02).

Conclusions

Ps and PsA patients did not present lower BMD. However, they had a higher prevalence of osteoporotic fractures and higher risk of metabolic syndrome. Patients with a longer duration of disease, disability and recurrent falls need preventive measures.

Soluble receptor activator of nuclear factor-kappaB ligand (RANKL) and osteoprotegerin in ankylosing spondylitis: OPG is associated with poor physical mobility and reflects systemic inflammation

The objective of the study was to investigate the role of receptor activator of nuclear factor-kappaB ligand (RANKL) and osteoprotegerin (OPG) in ankylosing spondylitis (AS). Serum levels of soluble RANKL (sRANKL) and OPG were measured in 42 AS patients and 26 healthy controls. We evaluated the AS patient's disease activity, functional ability, global assessment, and physical mobility and tested markers of systemic inflammation, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels. Serum levels of sRANKL [mean (SD), 4.75 (1.88) vs. 3.70 (1.14) pmol/l, p = 0.015] and OPG [mean (SD), 5.18 (1.19) vs. 4.52 (0.85) pmol/l, p = 0.026] were significantly higher in the 42 AS patients than the 26 healthy controls. Interestingly, serum OPG levels correlated significantly with ESR (r = 0.417, p = 0.007), CRP (r = 0.524, p < 0.001), tragus-to-wall distance (r = 0.556, p < 0.001), fingertip-to-floor distance (r = 0.423, p = 0.007), and occiput-to-wall distance (r = 0.465, p = 0.002) and correlated inversely with modified Schober index (r = -0.525, p = 0.001), cervical rotation (r = -0.403, p = 0.022), lateral lumbar flexion (r = -0.587, p < 0.001), and chest expansion (r = -0.553, p < 0.001). Moreover, in the AS patients with higher (> or =4.925 pmol/l, n = 21) serum OPG levels, there were significant increases in the tragus-to-wall distance (p = 0.007), fingertip-to-floor distance (p = 0.023), and CRP levels (p = 0.014) and decreased in the modified Schober index (p = 0.012), lateral lumbar flexion (p = 0.019), and chest expansion (p = 0.005). Serum levels of sRANKL and OPG are increased in the AS patients and may participate in the disease process of AS. Production of OPG has association with poor physical mobility and may reflect systemic inflammation in AS.

[Bone densitometry in inflammatory rheumatic diseases : Characteristics of the measurement site and disease-specific factors]

Bone densitometry should be performed earlier in patients with inflammatory arthritis, since factors such as inflammation and drug therapy, in particular treatment with glucocorticoids, have an important impact on the development of osteoporosis. DXA (Dual energy X-ray Absorptiometry) is considered the gold standard for bone densitometry. According to the German guidelines for osteoporosis, bone densitometry plays a crucial role in the choice of therapy.In patients with rheumatoid arthritis, measurement of peripheral bone (forearm) density in addition to lumbar spine and hip is recommended, since local bone loss is pathognomonic for this disease. DXA measurements of the hand enable the diagnosis of juxtaarticular osteoporosis at an earlier stage; however, this has not yet been established in routine practise.Bone measurement in patients with ankylosing spondylitis can be performed in the lumbar spine and the hip at disease onset. In systemic lupus erythematosus, bone loss is more frequent in patients with high inflammatory activity. Patients with psoriasis arthritis frequently have osteoporosis in the case of a destructive development of the joints.

The tumor necrosis factor-{alpha}-blocking agent infliximab inhibits interleukin 1beta (IL-1beta) and IL-6 gene expression in human osteoblastic cells

OBJECTIVE

Tumor necrosis factor-alpha (TNF-alpha) is a proinflammatory cytokine involved in the pathogenesis of several rheumatic diseases, including rheumatoid arthritis (RA), associated with systemic bone loss and subchondral bone erosions. TNF-alpha-blocking agents such as infliximab have been successful in treatment of disease-modifying antirheumatic drug-resistant rheumatic diseases. Infliximab therapy in RA also had beneficial effects on local bone destruction and bone mineral density. We assessed effects of infliximab treatment on the bone tissue compartment and cytokine profile expression in vitro.

METHODS

Osteoblast-like cells were exposed for 24 h to sera of RA patients collected at baseline and after 1 month (T1) and 3 years (T2) of infliximab treatment. Total RNA was extracted, and expression of interleukin 1beta (IL-1beta), IL-6, and osteoprotegerin (OPG) was measured by RT-PCR.

RESULTS

IL-1beta gene expression was significantly reduced by the T1 serum, and the same decrease was elicited by the T2 serum. IL-6 downregulation was evident with the T2 serum. OPG was unaffected.

CONCLUSION

The finding of downregulation of inflammatory cytokines was interesting, particularly IL-6, which plays a crucial role in arthritis-related bone loss due to its involvement in osteoclast recruitment and activation. These results may represent a biological explanation and a link for the clinical observation of the beneficial effects of anti-TNF-alpha agents on the progression of rheumatic diseases at the bone level.

Psoriasis and osteoporosis: a sex-specific association?

Previous reports showed associations between psoriasis and chronic diseases. Little is known about the association between osteoporosis and psoriasis. The goal of the study was to assess the association between psoriasis and osteoporosis in a population-based case-control study, utilizing the database of a large health-care provider organization in Israel, Clalit Health Services. Patients (aged 51-90 years) diagnosed with psoriasis were compared with a sample of age- and sex-matched enrollees without psoriasis regarding the prevalence of osteoporosis. Data on health-related lifestyles and other comorbidities were collected. The study included 7,936 psoriasis cases and 14,835 controls. The prevalence of osteoporosis was significantly greater in males with psoriasis compared with the control group (3.1 vs 1.7%, P<0.001, odds ratio (OR)=1.86, 95% confidence interval (CI): 1.44-2.39) and slightly greater in females with psoriasis (22.3 vs 20.2%, P=0.008, OR=1.13, 95% CI: 1.03-1.25). A multivariate logistic regression model demonstrated that after controlling for confounders, psoriasis was significantly associated with osteoporosis in males (adjusted OR=1.70, 95% CI: 1.31-2.19, P<0.001). The weak association between psoriasis and osteoporosis in females lost statistical significance in a multivariate model (adjusted OR=1.09, 95% CI: 0.98-1.21, P=0.100). Psoriasis was found to be associated with osteoporosis among males, but not among females.