The relationship between osteoclastogenic and anti-osteoclastogenic pro-inflammatory cytokines differs in human osteoporotic and osteoarthritic bone tissues

Background

Pro-inflammatory cytokines possess osteoclastogenic or anti-osteoclastogenic activities. They influence osteoclasts directly or via the receptor activator of nuclear factor κB (RANK), RANK ligand (RANKL) and osteoprotegerin (OPG) system. Recent evidence suggests that inflammation may play a role in osteoporosis (OP) and osteoarthritis (OA). We aimed therefore to determine whether there is a difference between both groups: first, in the expression of the osteoclastogenic and anti-osteoclastogenic cytokines, second, in correlation of these cytokines with bone mineral density (BMD) and levels of bone turnover markers (BTM) and third, in correlation between the expression of these cytokines and osteoclast specific genes and RANK/RANKL/OPG genes.

Methods

Human bone samples from 54 age and sex matched patients with OP or OA were collected during hip arthroplasty surgery. The expression of 25 genes encoding pro-inflammatory cytokines, their receptors, osteoclast specific genes and RANK/RANKL/OPG genes was measured using quantitative real-time PCR. Total hip, femoral neck and lumbar spine BMD and BTM in blood samples were measured. The comparison between OP and OA was assessed using Student''s t-test or Mann-Whitney U test and correlations between gene expression, BMD and BTM were determined using nonparametric correlation.

Results

The results demonstrated a higher expression of interleukin (IL)-6 and IL-1α in OP, and interferon (IFN)-γ in OA (p < 0.0005). Negative correlations of total hip BMD with tumor necrosis factor-α (TNF-α) in OA and with RANKL/RANK in OP were found (p < 0.05). Significant correlations with BTM were shown for IL-1α and IFN-γ in OP (rho = 0.608 and -0.634) and for TNF-α, IL-6 and transforming growth factor-β1 (TGF-β1) in OA (rho = 0.591, -0.521 and 0.636). Results showed OP specific negative correlations (IFN-γ with ITGB3, IFN-β1 with CTSK, tartrate resistant acid phosphatase (TRAP), CALCR, RANK, RANKL, IL-1α with CTSK, OPG, IL-17A with CALCR) and positive (TGF-β1 with CTSK, TRAP, RANK), and OA specific negative (IL-1α with osteoclast associated immunoglobulin-like receptor (OSCAR), TNF-α with RANK, RANKL, OPG) and positive (IL-6 with RANK, RANKL, OPG) correlations.

Conclusions

Our results demonstrate that the relationship between osteoclastogenic and anti-osteoclastogenic pro-inflammatory cytokines differs in human OP and OA bone and could present an important factor for characteristics of OP and OA bone phenotypes.     

Akt regulates IL-10 mediated suppression of TNFα-induced cardiomyocyte apoptosis by upregulating Stat3 phosphorylation

Background

We have already reported that TNF-α increases cardiomyocyte apoptosis and IL-10 treatment prevented these effects of TNF-α. Present study investigates the role of Akt and Jak/Stat pathway in the IL-10 modulation of TNF-α induced cardiomyocyte apoptosis.

Methodology/Principal findings

Cardiomyocytes isolated from adult Sprague Dawley rats were exposed to TNF-α (10 ng/ml), IL-10 (10 ng/ml) and TNF-α+IL-10 (ratio 1) for 4 h. Exposure to TNF-α resulted in an increase in cardiomyocyte apoptosis as measured by flow cytometry and TUNEL assay. IL-10 by itself had no effect, but it prevented TNF-α induced apoptosis. IL-10 treatment increased Akt levels within cardiomyocytes and this change was associated with an increase in Jak1 and Stat3 phosphorylation. Pre-exposure of cells to Akt inhibitor prevented IL-10 induced Stat3 phosphorylation. Furthermore, in the presence of Akt or Stat3 inhibitor, IL-10 treatment was unable to block TNF-α induced cardiomyocyte apoptosis.

Conclusion

It is suggested that IL-10 modulation of TNF-α induced cardiomyocyte apoptosis is mediated by Akt via Stat3 activation.     

Exercise Training Prevents TNF-α Induced Loss of Force in the Diaphragm of Mice

Rationale

Inflammatory cytokines like tumor necrosis factor alpha (TNF-α) are elevated in congestive heart failure and are known to induce the production of reactive oxygen species as well as to deteriorate respiratory muscle function.

Objectives

Given the antioxidative effects of exercise training, the aim of the present study was to investigate if exercise training is capable of preventing a TNF-α induced loss of diaphragmatic force in mice and, if so, to elucidate the potential underlying mechanisms.

Methods

Prior to intraperitoneal injection of TNF-α or saline, C57Bl6 mice were assigned to four weeks of exercise training or sedentary behavior. Diaphragmatic force and power generation were determined in vitro. Expression/activity of radical scavenger enzymes, enzymes producing reactive oxygen species and marker of oxidative stress were measured in the diaphragm.

Main Results

In sedentary animals, TNF-α reduced specific force development by 42% concomitant with a 2.6-fold increase in the amount of carbonylated α-actin and creatine kinase. Furthermore, TNF-α led to an increased NAD(P)H oxidase activity in both sedentary and exercised mice whereas xanthine oxidase activity and intramitochondrial ROS production was only enhanced in sedentary animals by TNF-α. Exercise training prevented the TNF-α induced force reduction and led to an enhanced mRNA expression and activity of glutathione peroxidase. Carbonylation of proteins, in particular of α-actin and creatine kinase, was diminished by exercise training.

Conclusion

TNF-α reduces the force development in the diaphragm of mice. This effect is almost abolished by exercise training. This may be a result of reduced carbonylation of proteins due to the antioxidative properties of exercise training.     

Serum sclerostin in high-activity adult patients with juvenile idiopathic arthritis

Introduction

Juvenile idiopathic arthritis (JIA) is a disease associated with loss of bone mass, deterioration in bone mass quality and an increased risk of fractures. The objective of this study was to evaluate factors that predict bone mineral density (BMD) alterations in young adult patients with active JIA before and during therapy with tumour necrosis factor α (TNFα) inhibitors.

Methods

Thirty-one patients (twelve males and nineteen females; mean age =25.1 ± 6.1 years) with active JIA (mean Disease Activity Score in 28 joints (DAS28) =6.36 ± 0.64; mean high-sensitivity C-reactive protein (hsCRP) =18.36 ± 16.95 mg/L) were investigated. The control group consisted of 84 healthy individuals matched by sex and age. BMD, bone turnover markers and serum concentrations of soluble receptor activator of nuclear factor κB ligand, osteoprotegerin, dickkopf Wnt signalling pathway inhibitor 1 (Dkk1) and sclerostin were evaluated.

Results

Baseline BMD values in the lumbar spine, proximal femur, femoral neck and distal radius were significantly lower in patients with JIA compared to healthy control participants. Baseline sclerostin serum concentrations were significantly higher in patients with JIA compared to control participants. After 2 years of treatment with TNFα inhibitors, BMD was significantly increased in the lumbar spine. This increase correlated with a drop in DAS28 score. A statistically significant correlation between hsCRP and Dkk1 was found at baseline, as well as during the 2-year follow-up period. A significant reduction in serum sclerostin after 1 year of therapy was predictive of a drop in DAS28 score observed with a 1-year delay after reduction of serum sclerostin.

Conclusion

A significant correlation between the sclerostin serum concentration and the number of tender and swollen joints, but not BMD, supports the hypothesis that chondrocytes and cells of the subchondral bone may contribute to circulating sclerostin in JIA.     

Quantiferon-TB Gold in tube assay for the screening of tuberculosis before and during treatment with tumor necrosis factor alpha antagonists

Introduction

The usefulness of interferon-gamma (IFN-γ) release assays for tuberculosis screening before tumor necrosis factor-alpha (TNF-α) antagonists and for monitoring during treatment is a contraversial issue. The aims of this study were to determine whether TNF-α antagonists affect the results of the Quantiferon-TB Gold in-tube assay (QTF); to assess how QTF performs in comparison with the tuberculin skin test (TST) in rheumatoid arthritis (RA) patients who are about to start treatment with TNF-α antagonists, RA patients who are not candidates for treatment with TNF-α antagonists, rheumatology patients with confirmed current or past tuberculosis infection, and healthy controls, and to determine the specificity of the QTF test to differentiate leprosy patients, another group of patients infected with mycobacteria.

Methods

The 38 RA patients who were prescribed TNF-α antagonists, 40 RA patients who were not considered for TNF-α antagonist use, 30 rheumatology patients with a history or new diagnosis of tuberculosis, 23 leprosy patients, and 41 healthy controls were studied. QTF and TST were done on the same day, and both were repeated after a mean of 3.6 ± 0.2 months in patients who used TNF-α antagonists.

Results

Treatment with TNF-α antagonists did not cause a significant change in the QTF or TST positivity rate (34% versus 42%; P = 0.64; and 24% versus 37%; P = 0.22). Patients with leprosy had a trend for a higher mean IFN-γ level (7.3 ± 8.0) and QTF positivity (61%) than did the other groups; however, the difference was not significant (P = 0.09 and P = 0.43).

Conclusions

Treatment with TNF-α antagonists does not seem to affect the QTF test to an appreciable degree. The higher IFN-γ levels in leprosy patients deserves further attention.     

Unlike for human monocytes after LPS activation, release of TNF-α by THP-1 cells is produced by a TACE catalytically different from constitutive TACE

Background

Tumor necrosis factor-alpha (TNF-α) is a pro-inflammatory cytokine today identified as a key mediator of several chronic inflammatory diseases. TNF-α, initially synthesized as a membrane-anchored precursor (pro-TNF-α), is processed by proteolytic cleavage to generate the secreted mature form. TNF-α converting enzyme (TACE) is currently the first and single protease described as responsible for the inducible release of soluble TNF-α.

Methodology/Principal Findings

Here, we demonstrated the presence on THP-1 cells as on human monocytes of a constitutive proteolytical activity able to cleave pro-TNF-α. Revelation of the cell surface TACE protein expression confirmed that the observed catalytic activity is due to TACE. However, further studies using effective and innovative TNF-α inhibitors, as well as a highly selective TACE inhibitor, support the presence of a catalytically different sheddase activity on LPS activated THP-1 cells. It appears that this catalytically different TACE protease activity might have a significant contribution to TNF-α release in LPS activated THP-1 cells, by contrast to human monocytes where the TACE activity remains catalytically unchanged even after LPS activation.

Conclusions/Significance

On the surface of LPS activated THP-1 cells we identified a releasing TNF-α activity, catalytically different from the sheddase activity observed on human monocytes from healthy donors. This catalytically-modified TACE activity is different from the constitutive shedding activity and appears only upon stimulation by LPS.     

The TNF-alpha-238 polymorphism and cancer risk: a meta-analysis

Background and Objectives

Tumor necrosis factor-α (TNF-α) plays a very important role in the development and progress of cancer. Some TNF-α polymorphisms have been confirmed to increase cancer risks; however, the association between TNF-α-238 polymorphism and cancers remains controversial and ambiguous. The aim of this study is to explore a more precise estimation of its relationship with cancer using meta-analysis.

Methods

Electronic searches of several databases were conducted for all publications on the association between this variant and cancer through March 2011. Odds ratios (OR) with 95% confidence intervals (95% CI) were used to access the strength of this association in the random-effect model.

Results

Thirty four studies with 34,679 cancer patients and 41,186 healthy controls were included. This meta-analysis showed no significant association between TNF-α-238 polymorphism and cancers (AA+GA vs GG: OR = 1.09, 95%CI = 0.88–1.34). In Caucasian and Asian subgroups, OR values (95% CI) were 1.14 (0.91–1.43) and 0.97 (0.58–1.61), respectively. In the subgroups of cancer type, no significant association was detected. The sensitivity analysis further strengthened the validity of these negative associations. No publication bias was observed in this study.

Conclusions

No significant association was found between the TNF-α-238 polymorphism and the risk for cancer.     

Association between Bone Mineral Density and Incidence of Breast Cancer

Introduction

Previous studies have suggested an inverse relationship between bone mineral density (BMD) and breast cancer incidence. The primary objective of this study was to assess whether BMD is associated with risk of subsequent breast cancer occurrence in the female population of southern Israel.

Methods

The electronic medical charts of women who underwent BMD at the Soroka Medical Center (SMC) between February 2003 and March 2011 were screened for subsequent breast cancer diagnoses. Women were divided by tertiles of BMD at 3 skeletal sites: lumbar spine (LS, L1–4), total hip (TH) and femoral neck (FN). The incidence of breast cancer was calculated.

Results

Of 15268 women who underwent BMD testing, 86 were subsequently diagnosed with breast cancer. Most women in the study were older than 50 years (94.2% and 92.7%, respectively; p = 0.597). Women who subsequently developed breast cancer had a higher mean body-mass index (BMI) (30.9±5.5 vs. 29.1±5.7 p = 0.004) and the mean BMD Z-score was significantly higher than in those without breast cancer for all 3 skeletal sites (LS: 0.36±1.58 vs. −0.12±1.42, p = 0.002; TH: 0.37±1.08 vs. 0.03±1.02, p = 0.002; FN: 0.04±0.99 vs. −0.18±0.94; p = 0.026). Women in the highest Z-score tertiles at the FN and TH had a higher chance of developing breast cancer compared to the lowest tertile; odds ratio of 2.15, 2.02, respectively (P = 0.004 and 0.01 respectively). No association was found between the BMD Z-score and the stage, histology, grade or survival from breast cancer.

Conclusions

This study provides additional support for an inverse association between BMD and the risk of breast cancer.     

Inhibitory effect of TNF-α on malaria pre-erythrocytic stage development: influence of host hepatocyte/parasite combinations

Background

The liver stages of malaria parasites are inhibited by cytokines such as interferon-γ or Interleukin (IL)-6. Binding of these cytokines to their receptors at the surface of the infected hepatocytes leads to the production of nitric oxide (NO) and radical oxygen intermediates (ROI), which kill hepatic parasites. However, conflicting results were obtained with TNF-α possibly because of differences in the models used. We have reassessed the role of TNF-α in the different cellular systems used to study the Plasmodium pre-erythrocytic stages.

Methods and Findings

Human or mouse TNF-α were tested against human and rodent malaria parasites grown in vitro in human or rodent primary hepatocytes, or in hepatoma cell lines. Our data demonstrated that TNF-α treatment prevents the development of malaria pre-erythrocytic stages. This inhibitory effect however varies with the infecting parasite species and with the nature and origin of the cytokine and hepatocytes. Inhibition was only observed for all parasite species tested when hepatocytes were pre-incubated 24 or 48 hrs before infection and activity was directed only against early hepatic parasite. We further showed that TNF-α inhibition was mediated by a soluble factor present in the supernatant of TNF-α stimulated hepatocytes but it was not related to NO or ROI. Treatment TNF-α prevents the development of human and rodent malaria pre-erythrocytic stages through the activity of a mediator that remains to be identified.

Conclusions

Treatment TNF-α prevents the development of human and rodent malaria pre-erythrocytic stages through the activity of a mediator that remains to be identified. However, the nature of the cytokine-host cell-parasite combination must be carefully considered for extrapolation to the human infection.     

Tumor necrosis factor-α regulates distinct molecular pathways and gene networks in cultured skeletal muscle cells

Background

Skeletal muscle wasting is a debilitating consequence of large number of disease states and conditions. Tumor necrosis factor-α (TNF-α) is one of the most important muscle-wasting cytokine, elevated levels of which cause significant muscular abnormalities. However, the underpinning molecular mechanisms by which TNF-α causes skeletal muscle wasting are less well-understood.

Methodology/Principal Findings

We have used microarray, quantitative real-time PCR (QRT-PCR), Western blot, and bioinformatics tools to study the effects of TNF-α on various molecular pathways and gene networks in C2C12 cells (a mouse myoblastic cell line). Microarray analyses of C2C12 myotubes treated with TNF-α (10 ng/ml) for 18h showed differential expression of a number of genes involved in distinct molecular pathways. The genes involved in nuclear factor-kappa B (NF-kappaB) signaling, 26s proteasome pathway, Notch1 signaling, and chemokine networks are the most important ones affected by TNF-α. The expression of some of the genes in microarray dataset showed good correlation in independent QRT-PCR and Western blot assays. Analysis of TNF-treated myotubes showed that TNF-α augments the activity of both canonical and alternative NF-κB signaling pathways in myotubes. Bioinformatics analyses of microarray dataset revealed that TNF-α affects the activity of several important pathways including those involved in oxidative stress, hepatic fibrosis, mitochondrial dysfunction, cholesterol biosynthesis, and TGF-β signaling. Furthermore, TNF-α was found to affect the gene networks related to drug metabolism, cell cycle, cancer, neurological disease, organismal injury, and abnormalities in myotubes.

Conclusions

TNF-α regulates the expression of multiple genes involved in various toxic pathways which may be responsible for TNF-induced muscle loss in catabolic conditions. Our study suggests that TNF-α activates both canonical and alternative NF-κB signaling pathways in a time-dependent manner in skeletal muscle cells. The study provides novel insight into the mechanisms of action of TNF-α in skeletal muscle cells.     

Low bone mineral density in men with chronic obstructive pulmonary disease

Background

Osteoporosis is common in patients with COPD but the likely multi-factorial causes contributing to this condition (e.g. sex, age, smoking, therapy) mask the potential contribution from elements related to COPD. In order to study osteoporosis and bone mineral density (BMD) related to COPD, we studied a well-defined group of patients and controls.

Methods

BMD, forced expiratory volume in one second (FEV₁), circulating bone biomarkers and biochemistry were determined in 30 clinically stable male ex-smokers with confirmed COPD and 15 age matched "ex-smoker" male controls. None of the patients were on inhaled corticosteroids or received more than one short course of steroids.

Results

Mean (SD) FEV₁% predicted of patients was 64(6)%, the majority having Global Initiative for Chronic Obstructive Lung Disease (GOLD) II airflow obstruction. There were 5/30 patients and 1/15 controls who were osteoporotic, while a further 17 patients and 5 controls were osteopenic. The BMD at the hip was lower in patients than controls, but not at the lumbar spine. Mean values of procollagen type 1 amino-terminal propeptide and osteocalcin, both markers of bone formation, and Type 1 collagen β C-telopeptide, a marker of bone resorption, were similar between patients and controls. However, all bone biomarkers were inversely related to hip BMD in patients (r = -0.51, r = -0.67, r = -0.57, p < 0.05) but did not relate to lumbar spine BMD. 25-OH Vitamin D was lower in patients.

Conclusions

Men with COPD had a greater prevalence of osteoporosis and osteopenia than age matched male controls, with a marked difference in BMD at the hip. Bone biomarkers suggest increased bone turnover.     

Regulation of endothelial cell adhesion molecule expression by mast cells, macrophages, and neutrophils

Background

Leukocyte adhesion to the vascular endothelium and subsequent transendothelial migration play essential roles in the pathogenesis of cardiovascular diseases such as atherosclerosis. The leukocyte adhesion is mediated by localized activation of the endothelium through the action of inflammatory cytokines. The exact proinflammatory factors, however, that activate the endothelium and their cellular sources remain incompletely defined.

Methods and Results

Using bone marrow-derived mast cells from wild-type, Tnf^−/−, Ifng^−/−, Il6^−/− mice, we demonstrated that all three of these pro-inflammatory cytokines from mast cells induced the expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), P-selectin, and E-selectin in murine heart endothelial cells (MHEC) at both mRNA and protein levels. Compared with TNF-α and IL6, IFN-γ appeared weaker in the induction of the mRNA levels, but at protein levels, both IL6 and IFN-γ were weaker inducers than TNF-α. Under physiological shear flow conditions, mast cell-derived TNF-α and IL6 were more potent than IFN-γ in activating MHEC and in promoting neutrophil adhesion. Similar observations were made when neutrophils or macrophages were used. Neutrophils and macrophages produced the same sets of pro-inflammatory cytokines as did mast cells to induce MHEC adhesion molecule expression, with the exception that macrophage-derived IFN-γ showed negligible effect in inducing VCAM-1 expression in MHEC.

Conclusion

Mast cells, neutrophils, and macrophages release pro-inflammatory cytokines such as TNF-α, IFN-γ, and IL6 that induce expression of adhesion molecules in endothelium and recruit of leukocytes, which is essential to the pathogenesis of vascular inflammatory diseases.     

Decreased Expression of Vitamin D Receptors in Neointimal Lesions following Coronary Artery Angioplasty in Atherosclerotic Swine

Background

Inflammatory cytokines, such as TNF-α, play a key role in the pathogenesis of occlusive vascular diseases. Activation of vitamin D receptors (VDR) elicits both growth-inhibitory and anti-inflammatory effects. Here, we investigated the expression of TNF-α and VDR in post-angioplasty coronary artery neointimal lesions of hypercholesterolemic swine and examined the effect of vitamin D deficiency on the development of coronary restenosis. We also examined the effect of calcitriol on cell proliferation and effect of TNF-α on VDR activity and expression in porcine coronary artery smooth muscle cells (PCASMCs) in-vitro.

Methodology/Principal Findings

Expression of VDR and TNF-α and the effect of vitamin D deficiency in post-angioplasty coronary arteries were analyzed by immunohistochemistry and histomorphometry. Cell proliferation was examined by thymidine and BrdU incorporation assays in cultured PCASMCs. Effect of TNF-α-stimulation on the activity and expression of VDR was analyzed by luciferase assay, immunoblotting and immunocytochemistry. In-vivo, morphometric analysis of the tissues revealed typical lesions with significant neointimal proliferation. Histological evaluation showed expression of smooth muscle α-actin and significantly increased expression of TNF-α in neointimal lesions. Interestingly, there was significantly decreased expression of VDR in PCASMCs of neointimal region compared to normal media. Indeed, post-balloon angioplasty restenosis was significantly higher in vitamin D-deficient hypercholesterolemic swine compared to vitamin D-sufficient group. In-vitro, calcitriol inhibited both serum- and PDGF-BB-induced proliferation in PCASMCs and TNF-α-stimulation significantly decreased the expression and activity of VDR in PCASMCs.

Conclusions/Significance

These data suggest that significant downregulation of VDR in proliferating smooth muscle cells in neointimal lesions could be due to atherogenic cytokines, including TNF-α. Vitamin D deficiency potentiates the development of coronary restenosis. Calcitriol has anti-proliferative properties in PCASMCs and these actions are mediated through VDR. This could be a potential mechanism for uncontrolled growth of neointimal cells in injured arteries leading to restenosis.     

Levels and determinants of inflammatory biomarkers in a Swiss population-based sample (CoLaus study)

Objective

to assess the levels and determinants of interleukin (IL)-1β, IL-6, tumour necrosis factor (TNF)-α and C-reactive protein (CRP) in a healthy Caucasian population.

Methods

population sample of 2884 men and 3201 women aged 35 to 75. IL-1β, IL-6 and TNF-α were assessed by a multiplexed particle-based flow cytometric assay and CRP by an immunometric assay.

Results

Spearman rank correlations between duplicate cytokine measurements (N = 80) ranged between 0.89 and 0.96; intra-class correlation coefficients ranged between 0.94 and 0.97, indicating good reproducibility. Among the 6085 participants, 2289 (37.6%), 451 (7.4%) and 43 (0.7%) had IL-1β, IL-6 and TNF-α levels below detection limits, respectively. Median (interquartile range) for participants with detectable values were 1.17 (0.48–3.90) pg/ml for IL-1β; 1.47 (0.71–3.53) pg/ml for IL-6; 2.89 (1.82–4.53) pg/ml for TNF-α and 1.3 (0.6–2.7) ng/ml for CRP. On multivariate analysis, greater age was the only factor inversely associated with IL-1β levels. Male sex, increased BMI and smoking were associated with greater IL-6 levels, while no relationship was found for age and leisure-time PA. Male sex, greater age, increased BMI and current smoking were associated with greater TNF-α levels, while no relationship was found with leisure-time PA. CRP levels were positively related to age, BMI and smoking, and inversely to male sex and physical activity.

Conclusion

Population-based levels of several cytokines were established. Increased age and BMI, and to a lesser degree sex and smoking, significantly and differentially impact cytokine levels, while leisure-time physical activity has little effect.     

Bone Mineral Density,Bone Turnover Markers and Fractures in Patients with Systemic Sclerosis: A Case Control Study

Objective

The aim of our study was to elucidate the pathophysiology of systemic sclerosis-related osteoporosis and the prevalence of vertebral fragility fracture in postmenopausal women with systemic sclerosis (SSc).

Methodology

Fifty-four postmenopausal women with scleroderma and 54 postmenopausal controls matched for age, BMI, and smoking habits were studied. BMD was measured by dual energy-x-ray absorptiometry at spine and femur, and by ultrasonography at calcaneus The markers of bone turnover included serum osteocalcin and urinary deoxypyridinoline. All subjects had a spine X-ray to ascertain the presence of vertebral fractures.

Results

bone mineral density at lumbar spine (BMD 0.78±0.08 vs 0.88±0.07; p<0,001), femoral neck (BMD: 0.56±0.04 vs 0.72±0.07; p<0,001) and total femur (BMD: 0.57±0.04 vs 0.71±0.06; p<0,001) and ultrasound parameter at calcaneus (SI: 80.10±5.10 vs 94.80±6.10 p<0,001) were significantly lower in scleroderma compared with controls; bone turnover markers and parathyroid hormone level were significantly higher in scleroderma compared with controls, while serum of 25(OH)D3 was significantly lower. In scleroderma group the serum levels of 25(OH)D3 significantly correlated with PTH levels, BMD, stiffness index and bone turnover markers. One or more moderate or severe vertebral fractures were found in 13 patients with scleroderma, wherease in control group only one patient had a mild vertebral fracture.

Conclusion

Our data shows, for the first time, that vertebral fractures are frequent in subjects with scleroderma, and suggest that lower levels of 25(OH)D3 may play a role in the risk of osteoporosis and vertebral fractures.     

Type I Interferon: Potential Therapeutic Target for Psoriasis?

Background

Psoriasis is an immune-mediated disease characterized by aberrant epidermal differentiation, surface scale formation, and marked cutaneous inflammation. To better understand the pathogenesis of this disease and identify potential mediators, we used whole genome array analysis to profile paired lesional and nonlesional psoriatic skin and skin from healthy donors.

Methodology/Principal Findings

We observed robust overexpression of type I interferon (IFN)–inducible genes and genomic signatures that indicate T cell and dendritic cell infiltration in lesional skin. Up-regulation of mRNAs for IFN-α subtypes was observed in lesional skin compared with nonlesional skin. Enrichment of mature dendritic cells and 2 type I IFN–inducible proteins, STAT1 and ISG15, were observed in the majority of lesional skin biopsies. Concordant overexpression of IFN-γ and TNF-α–inducible gene signatures occurred at the same disease sites.

Conclusions/Significance

Up-regulation of TNF-α and elevation of the TNF-α–inducible gene signature in lesional skin underscore the importance of this cytokine in psoriasis; these data describe a molecular basis for the therapeutic activity of anti–TNF-α agents. Furthermore, these findings implicate type I IFNs in the pathogenesis of psoriasis. Consistent and significant up-regulation of type I IFNs and their associated gene signatures in psoriatic skin suggest that type I IFNs may be potential therapeutic targets in psoriasis treatment.     

Comparison of bone and renal effects in HIV-infected adults switching to abacavir or tenofovir based therapy in a randomized trial

Introduction

Our objective was to compare the bone and renal effects among HIV-infected patients randomized to abacavir or tenofovir-based combination anti-retroviral therapy.

Methods

In an open-label randomized trial, HIV-infected patients were randomized to switch from zidovudine/lamivudine (AZT/3TC) to abacavir/lamivudine (ABC/3TC) or tenofovir/emtricitabine (TDF/FTC). We measured bone mass density (BMD) and bone turnover biomarkers (osteocalcin, osteocalcin, procollagen type 1 N-terminal propeptide (P1NP), alkaline phosphatase, type I collagen cross-linked C-telopeptide (CTx), and osteoprotegerin). We assessed renal function by estimated creatinine clearance, plasma cystatin C, and urinary levels of creatinine, albumin, cystatin C, and neutrophil gelatinase-associated lipocalin (NGAL). The changes from baseline in BMD and renal and bone biomarkers were compared across study arms.

Results

Of 40 included patients, 35 completed 48 weeks of randomized therapy and follow up. BMD was measured in 33, 26, and 27 patients at baseline, week 24, and week 48, respectively. In TDF/FTC-treated patients we observed significant reductions from baseline in hip and lumbar spine BMD at week 24 (−1.8% and −2.5%) and week 48 (−2.1% and −2.1%), whereas BMD was stable in patients in the ABC/3TC arm. The changes from baseline in BMD were significantly different between study arms. All bone turnover biomarkers except osteoprotegerin increased in the TDF/FTC arm compared with the ABC/3TC arm, but early changes did not predict subsequent loss of BMD. Renal function parameters were similar between study arms although a small increase in NGAL was detected among TDF-treated patients.

Conclusion

Switching to TDF/FTC-based therapy led to decreases in BMD and increases in bone turnover markers compared with ABC/3TC-based treatment. No major difference in renal function was observed.

Trial registration

Clinicaltrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00647244","term_id":"NCT00647244"}}NCT00647244