Associations between circulating endostatin levels and vascular organ damage in systemic sclerosis and mixed connective tissue disease: an observational study

IntroductionSystemic sclerosis (SSc) and mixed connective tissue disease (MCTD) are chronic immune-mediated disorders complicated by vascular organ damage. The aim of this study was to examine the serum levels of the markers of neoangiogenesis: endostatin and vascular endothelial growth factor (VEGF), in our unselected cohorts of SSc and MCTD.MethodsSera of SSc patients (N = 298) and MCTD patients (N = 162) from two longitudinal Norwegian cohorts were included. Blood donors were included as controls (N = 100). Circulating VEGF and endostatin were analyzed by enzyme immunoassay.ResultsMean endostatin levels were increased in SSc patients 93.7 (37) ng/ml (P < .001) and MCTD patients 83.2 (25) ng/ml (P < .001) compared to controls 65.1 (12) ng/ml. Median VEGF levels were elevated in SSc patients 209.0 (202) pg/ml compared to MCTD patients 181.3 (175) pg/ml (P = .017) and controls 150.0 (145) pg/ml (P < .001). Multivariable analysis of SSc subsets showed that pulmonary arterial hypertension (coefficient 15.7, 95 % CI: 2.2–29.2, P = .023) and scleroderma renal crisis (coefficient 77.6, 95 % CI: 59.3–100.0, P < .001) were associated with elevated endostatin levels. Multivariable analyses of MCTD subsets showed that digital ulcers were associated with elevated endostatin levels (coefficient 10.5, 95 % CI: 3.2–17.8, P = .005). The risk of death increased by 1.6 per SD endostatin increase (95 % CI: 1.2–2.1, P = .001) in the SSc cohort and by 1.6 per SD endostatin increase (95 % CI: 1.0–2.4, P = .041) in the MCTD cohort after adjustments to known risk factors.ConclusionsEndostatin levels were elevated in patients with SSc and MCTD, particularly SSc patients with pulmonary arterial hypertension and scleroderma renal crisis, and MCTD patients with digital ulcers. Elevated endostatin levels were also associated with increased all-cause mortality during follow-up in both groups of patients. We propose that endostatin might indicate the degree of vascular injury in SSc and MCTD patients.

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Meniscal extrusion promotes knee osteoarthritis structural progression: protective effect of strontium ranelate treatment in a phase III clinical trial

IntroductionTo evaluate the impact of meniscal extrusion (Ext) on knee osteoarthritis (OA) structural progression and on response to strontium ranelate (SrRan) treatment at 36 months in patients with (+) or without (-) Ext, in association (+) or not (-) with bone marrow lesions (BML) in the medial compartment using X-rays (JSW) and qMRI.MethodsPatients from the qMRI substudy of the SEKOIA trial (SrRan 1 g/day, n = 113; SrRan 2 g/day, n = 105; placebo, n = 112) were stratified based on whether meniscal extrusion and/or BML were present or not in the medial compartment.ResultsIn the placebo group, Ext+ patients (n = 26) had more JSW loss (p = 0.002) and cartilage volume loss in the global knee (p = 0.034) and plateau (p = 0.005), and medial compartment (p = 0.0005) than Ext- patients (n = 86). Ext-BML+ patients (n = 18) demonstrated more JSW loss (p = 0.003) and cartilage volume loss in the global (p = 0.020) and medial femur (p = 0.055) than Ext-BML- (n = 68). Compared to Ext+ BML- (n = 14), Ext+ BML+ patients (n = 12) had more cartilage volume loss in the global femur (p = 0.028), with no change in JSW. The JSW loss (p = 0.0004) and cartilage volume loss (global knee, p = 0.033, medial compartment, p = 0.0005) were greater when Ext and BML were simultaneously present in the medial compartment. SrRan 2 g/day treatment demonstrated a reduction in OA knee structural progression with qMRI, but not with JSW, in which less cartilage volume loss was found in the plateaus (p = 0.007) in Ext+ patients (n = 15), and in the medial plateau (p = 0.046) in patients in whom both Ext and BML were co-localized.ConclusionThe findings of this study are novel and could have an impact on future strategies regarding clinical trials. Indeed, data first argue for a combined, cumulative effect of meniscal extrusion and bone marrow lesions on cartilage loss and, secondly, they showed that SrRan may have protective effects in OA patients with meniscal extrusion as well as when both meniscal extrusion and BML are co-localized.     

Association of CXCL10 and CXCL13 levels with disease activity and cutaneous manifestation in active adult-onset Still’s disease

IntroductionC-X-C motif chemokine 10 (CXCL10) is produced in response to interferon-γ, and tumor necrosis factor-α (TNF-α) triggers the accumulation of activated lymphocytes. CXCL13 is constitutively expressed in secondary lymphoid tissues, and the expression is upregulated by TNF-α, via T cell stimulation. It appears that CXCL10 and CXCL13 could play a potential role in the pathogenesis of adult-onset Still’s disease (AOSD), therefore, we investigated the associations between CXCL10 and CXCL13 levels and clinical manifestations in patients with active AOSD.MethodsBlood samples were collected from 39 active AOSD patients, 32 rheumatoid arthritis (RA) patients and 40 healthy controls (HC). Of the AOSD patients, follow-up samples were collected from 15 9.6 ± 9.2 months later. Serum levels of CXCL10 and CXCL13 were determined using enzyme-linked immunosorbent assay. CXCL10, CXCL13, and C-X-C chemokine receptor type 3 (CXCR3) expression levels in biopsy specimens obtained from 26 AOSD patients with skin rashes were investigated via immunohistochemistry.ResultsThe CXCL10 levels in AOSD patients (1,031.3 ± 2,019.6 pg/mL) were higher than in RA (146.3 ± 91.4 pg/mL, p = 0.008) and HC (104.4 ± 47.9 pg/mL, p = 0.006). Also, the CXCL13 levels of AOSD patients (158.8 ± 151.2 pg/mL) were higher than those of RA (54.4 ± 61.1 pg/mL, p < 0.001) and HC (23.5 ± 18.1 pg/mL, p < 0.001). Serum CXCL10 levels correlated with ferritin and systemic scores. Serum CXCL13 levels correlated with those of hemoglobin, C-reactive protein, ferritin, and albumin, and systemic scores. In follow-up AOSD patients, the levels of CXCL10 and CXCL13 fell significantly (153.7 ± 130.1 pg/mL, p = 0.002, and 89.1 ± 117.4 pg/mL, p = 0.001, respectively). On immunohistochemistry, the percentages of inflammatory cells expressing CXCL10 ranged from 1 to 85 %, CXCL13 from 1 to 72 %, and CXCR3 from 2 to 65 %. The percentage of CXCL10-positive inflammatory cells was higher in skin biopsy samples exhibiting mucin deposition than in those that did not (p = 0.01). CXCL13 levels were correlated with those of CD4 and CD68.ConclusionsSerum CXCL10 and CXCL13 levels may serve as clinical markers for assessment of disease activity in AOSD. CXCL10/CXCR3 and CXCL13 may contribute to the inflammatory response, especially skin manifestations thereof, in AOSD.

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Increased plasma mannose binding lectin levels are associated with bronchiolitis obliterans after lung transplantation

Background

Long-term lung allograft survival is limited by bronchiolitis obliterans syndrome (BOS). Mannose binding lectin (MBL) belongs to the innate immune system, participates in complement activation, and may predispose to graft rejection. We investigated mannose binding (MBL) during cold ischemia and in tissue samples from explanted lungs with BOS, and assessed MBL and complement proteins in plasma post-lung transplantation relative to BOS staging.

Methods

MBL was detected by immunohistochemistry lung tissue at the time of cold ischemia and in samples with BOS. MBL was assayed in the peripheral blood of 66 lung transplant patients transplanted between 1990–2007.

Results

MBL localized to vasculature and basement membrane during cold ischemia and BOS. Patients further out post-lung transplant > 5 years (n = 33), had significantly lower levels of MBL in the blood compared to lung transplant patients < 5 years with BOS Op-3 (n = 17), 1738 ± 250 ng/ml vs 3198 ± 370 ng/ml, p = 0.027, and similar levels to lung transplant patients < 5 years with BOS 0 (n = 16), 1738 ± 250 ng/ml vs 1808 ± 345 ng/ml. MBL levels in all BOS 0 (n = 30) vs. all BOS Op-3 (n = 36) were 1378 ± 275 ng/ml vs. 2578 ± 390 ng/ml, p = 0.001, respectively. C3 plasma levels in BOS 0 (n = 30) vs. BOS Op-3 (n = 36) were 101 ± 19.8 mg/ml vs. 114 ± 25.2 mg/ml, p = 0.024, respectively.

Conclusions

MBL localizes within the lung during graft ischemia and BOS, higher levels of plasma MBL are associated with BOS Op-3 and < 5 years post-transplant, and higher level of plasma complement protein C3 was associated with BOS Op-3 clinical status. MBL may serve as a biomarker for poorer outcome post-lung transplantation.     

Interleukin-19 Impairment in Active Crohn’s Disease Patients

The exact function of interleukin-19 (IL-19) on immune response is poorly understood. In mice, IL-19 up-regulates TNFα and IL-6 expression and its deficiency increases susceptibility to DSS-induced colitis. In humans, IL-19 favors a Th2 response and is elevated in several diseases. We here investigate the expression and effects of IL-19 on cells from active Crohn’s disease (CD) patient. Twenty-three active CD patients and 20 healthy controls (HC) were included. mRNA and protein IL-19 levels were analyzed in monocytes. IL-19 effects were determined in vitro on the T cell phenotype and in the production of cytokines by immune cells. We observed that unstimulated and TLR-activated monocytes expressed significantly lower IL-19 mRNA in active CD patients than in HC (logFC = −1.97 unstimulated; −1.88 with Pam3CSK4; and −1.91 with FSL-1; p<0.001). These results were confirmed at protein level. Exogenous IL-19 had an anti-inflammatory effect on HC but not on CD patients. IL-19 decreased TNFα production in PBMC (850.7±75.29 pg/ml vs 2626.0±350 pg/ml; p<0.01) and increased CTLA4 expression (22.04±1.55% vs 13.98±2.05%; p<0.05) and IL-4 production (32.5±8.9 pg/ml vs 13.5±2.9 pg/ml; p<0.05) in T cells from HC. IL-10 regulated IL-19 production in both active CD patients and HC. We observed that three of the miRNAs that can modulate IL-19 mRNA expression, were up-regulated in monocytes from active CD patients. These results suggested that IL-19 had an anti-inflammatory role in this study. Defects in IL-19 expression and the lack of response to this cytokine could contribute to inflammatory mechanisms in active CD patients.     

Vitamin D deficiency in chronic inflammatory rheumatic diseases: results of the cardiovascular in rheumatology [CARMA] study

IntroductionThe aim was to study the association between 25-hydroxyvitamin D (25(OH)D) levels and the clinical characteristics of patients with chronic inflammatory rheumatic diseases (CIRD).MethodsWe studied a cross-section from the baseline visit of the CARMA project (CARdiovascular in rheuMAtology), a 10-year prospective study evaluating the risk of cardiovascular events in rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) patients, and non-CIRD patients who attended rheumatology outpatient clinics from 67 hospitals in Spain. Non-CIRD group was frequency matched by age with the joint distribution of the three CIRD groups included in the study. 25(OH)D deficiency was defined if 25(OH)D vitamin levels were < 20 ng/ml.Results2.234 patients (775 RA, 738 AS and 721 PsA) and 677 non-CIRD subjects were assessed. The median (p25-p75) 25(OH)D levels were: 20.4 (14.4-29.2) ng/ml in RA, 20.9 (13.1-29.0) in AS, 20.0 (14.0-28.8) in PsA, and 24.8 (18.4-32.6) ng/ml in non-CIRD patients. We detected 25(OH)D deficiency in 40.5 % RA, 39.7 % AS, 40.9 % PsA and 26.7 % non-CIRD controls (p < 0.001). A statistically significant positive association between RA and 25(OH)D deficiency was found (adjusted (adj.) OR = 1.46; 95 % CI = 1.09-1.96); p = 0.012. This positive association did not reach statistical significance for AS (adj. OR 1.23; 95 % CI = 0.85-1.80) and PsA (adj. OR 1.32; 95 % CI = 0.94-1.84). When the parameters of disease activity, severity or functional impairment were assessed, a marginally significant association between 25(OH)D deficiency and ACPA positivity in RA patients (adj. OR = 1.45; 95 % CI = 0.99-2.12; p = 0.056), and between 25(OH)D deficiency and BASFI in AS patients (adj. OR = 1.08; 95 % CI = 0.99-1.17); p = 0.07) was also found.ConclusionsPatients with RA show an increased risk of having 25(OH)D deficiency compared to non-CIRD controls.

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Decreased expression of the endothelial cell-derived factor EGFL7 in systemic sclerosis: potential contribution to impaired angiogenesis and vasculogenesis

Introduction

Microvascular damage and defective angiogenesis and vasculogenesis have a major role in the pathogenesis of systemic sclerosis (SSc). Epidermal growth factor-like domain 7 (EGFL7) is a proangiogenic molecule which is predominantly expressed and secreted by endothelial cells and their progenitors and controls vascular development and integrity. In this study, we investigated the possible involvement of EGFL7 in SSc.

Methods

Serum EGFL7 levels from 60 patients with SSc and 35 age- and sex-matched healthy controls were examined by colorimetric sandwich enzyme-linked immunosorbent assay. The expression of EGFL7 in forearm skin biopsies (n = 16 SSc, n = 10 controls), cultured dermal microvascular endothelial cells (MVECs) (n = 3 SSc, n = 3 controls) and late-outgrowth peripheral blood endothelial progenitor cell (EPC)-derived endothelial cells (n = 15 SSc, n = 8 controls) was investigated by immunofluorescence and Western blotting.

Results

Serum EGFL7 levels were detectable in 68.6% of healthy controls and 45% of SSc cases (P < 0.05). Circulating levels of EGFL7 were significantly decreased in SSc patients compared with healthy controls (P = 0.01). Serum levels of EGFL7 were significantly lower in both limited cutaneous SSc and diffuse cutaneous SSc patients than in controls (P = 0.02 and P = 0.04, respectively). In SSc, decreased serum EGFL7 levels were significantly correlated with the severity of nailfold capillary abnormalities. Patients with the most severe capillary changes and digital ulcers had serum EGFL7 levels significantly lower than healthy controls, while the EGFL7 levels did not differ significantly between controls and SSc patients with less capillary damage and lack of digital ulcers. Endothelial EGFL7 expression was strongly downregulated or even almost completely undetectable in SSc-affected dermis compared with controls (P < 0.001). In cultured SSc dermal MVECs and late-outgrowth peripheral blood EPC-derived endothelial cells, EGFL7 was significantly downregulated compared with cells obtained from healthy subjects (P < 0.01 and P < 0.001, respectively).

Conclusions

Our findings suggest that the loss of EGFL7 expression in endothelial cells and their progenitors might play a role in the development and progression of peripheral microvascular damage and the defective vascular repair process characteristic of SSc.     

Cutaneous Chronic Graft-Versus-Host Disease Does Not Have the Abnormal Endothelial Phenotype or Vascular Rarefaction Characteristic of Systemic Sclerosis

Background

The clinical and histologic appearance of fibrosis in cutaneous lesions in chronic graft-versus -host disease (c-GVHD) resembles the appearance of fibrosis in scleroderma (SSc). Recent studies identified distinctive structural changes in the superficial dermal microvasculature and matrix of SSc skin. We compared the dermal microvasculature in human c-GVHD to SSc to determine if c-GVHD is a suitable model for SSc.

Methodology/Principal Findings

We analyzed skin biopsies of normal controls (n = 24), patients with SSc (n = 30) and c-GVHD with dermal fibrosis (n = 133)). Immunostaining was employed to identify vessels, vascular smooth muscle, dermal matrix, and cell proliferation. C-GVHD and SSc had similar dermal matrix composition and vascular smooth muscle pathology, including intimal hyperplasia. SSc, however, differed significantly from c-GVHD in three ways. First, there were significantly fewer (p = 0.00001) average vessels in SSc biopsies (9.8) when compared with c-GVHD (16.5). Second, in SSc, endothelial markers were decreased significantly (19/19 and 12/14 for VE cadherin and vWF (p = <0.0001 and <0.05), respectively). In contrast, 0/13 c-GVHD biopsies showed loss of staining with canonical endothelial markers. Third, c-GVHD contained areas of microvascular endothelial proliferation not present in the SSc biopsies.

Conclusions/Significance

The sclerosis associated with c-GVHD appears to resemble wound healing. Focal capillary proliferation occurs in early c-GVHD. In contrast, loss of canonical endothelial markers and dermal capillaries is seen in SSc, but not in c-GVHD. The loss of VE cadherin in SSc, in particular, may be related to microvascular rarefaction because VE cadherin is necessary for angiogenesis. C-GVHD is a suitable model for studying dermal fibrosis but may not be applicable for studying the microvascular alterations characteristic of SSc.     

Leptin modulates electrophysiological characteristics and isoproterenol-induced arrhythmogenesis in atrial myocytes

Background

Obesity is an important risk factor for atrial fibrillation (AF). Leptin is an important adipokine. However, it is not clear whether leptin directly modulates the electrophysiological characteristics of atrial myocytes.

Results

Whole cell patch clamp and indo-1 fluorescence were used to record the action potentials (APs) and ionic currents in isolated rabbit left atrial (LA) myocytes incubated with and without (control) leptin (100 nM) for 1 h to investigate the role of leptin on atrial electrophysiology. Leptin-treated LA myocytes (n = 19) had longer 20% of AP duration (28 ± 3 vs. 21 ± 2 ms, p < 0.05), but similar 50% of AP duration (51 ± 4 vs. 50 ± 3 ms, p > 0.05), and 90% of AP duration (89 ± 5 vs. 94 ± 4 ms, p > 0.05), as compared to the control (n = 22). In the presence of isoproterenol (10 nM), leptin-treated LA myocytes (n = 21) showed a lower incidence (19% vs. 54.2%, p < 0.05) of delayed afterdepolarization (DAD) than the control (n = 24). Leptin-treated LA myocytes showed a larger sodium current, but a smaller ultra-rapid delayed rectifier potassium current, and sodium-calcium exchanger current than the control. Leptin-treated and control LA myocytes exhibited a similar late sodium current, inward rectifier potassium current, transient outward current and L-type calcium current. In addition, the leptin-treated LA myocytes (n = 38) exhibited a smaller intracellular Ca²⁺ transient (0.21 ± 0.01 vs. 0.26 ± 0.01 R410/485, p < 0.05) and sarcoplasmic reticulum Ca²⁺ content (0.35 ± 0.02 vs. 0.43 ± 0.03 R410/485, p < 0.05) than the control LA myocytes (n = 42).

Conclusions

Leptin regulates the LA electrophysiological characteristics and attenuates isoproterenol-induced arrhythmogenesis.     

A candidate gene study reveals association between a variant of the Peroxisome Proliferator-Activated Receptor Gamma (PPAR-γ) gene and systemic sclerosis

IntroductionThe multifunctional nuclear receptor peroxisome proliferator-activated receptor gamma (PPAR-γ) has potent anti-fibrotic effects, and its expression and activity are impaired in patients with systemic sclerosis (SSc). We investigated PPAR-γ gene (PPARG) single nucleotide polymorphisms (SNPs) associated with SSc.MethodsTag SNPs spanning PPARG were genotyped in a European ancestry US discovery cohort comprising 152 SSc patients and 450 controls, with replication of our top signal in a European cohort (1031 SSc patients and 1014 controls from France). Clinical parameters and disease severity were analyzed to evaluate clinical associations with PPARG variants.ResultsIn the discovery cohort, a single PPARG intronic SNP (rs10865710) was associated with SSc (p = 0.010; odds ratio = 1.52 per C allele, 95% confidence interval 1.10-2.08). This association was replicated in the French validation cohort (p = 0.052; odds ratio = 1.16 per C allele, 95% confidence interval 1.00-1.35). Meta-analysis of both cohorts indicated stronger evidence for association (p = 0.002; odds ratio = 1.22 per C allele, 95% confidence interval 1.07-1.40). The rs10865710 C allele was also associated with pulmonary arterial hypertension in the French SSc cohort (p = 0.002; odds ratio = 2.33 per C allele, 95% confidence interval 1.34-4.03).ConclusionsA PPARG variant is associated with susceptibility to SSc, consistent with a role of PPAR-γ in the pathogenesis of SSc.

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Severe and uncontrolled adult asthma is associated with vitamin D insufficiency and deficiency

Background

Vitamin D has effects on the innate and adaptive immune system. In asthmatic children low vitamin D levels are associated with poor asthma control, reduced lung function, increased medication intake, and exacerbations. Little is known about vitamin D in adult asthma patients or its association with asthma severity and control.

Methods

Clinical parameters of asthma control and 25-hydroxyvitamin D (25(OH)D) serum concentrations were evaluated in 280 adult asthma patients (mean ± SD: 45.0 ± 13.8 yrs., 40% male, FEV1 74.9 ± 23.4%, 55% severe, 51% uncontrolled).

Results

25(OH)D concentrations in adult asthmatics were low (25.6 ±11.8 ng/ml) and vitamin D insufficiency or deficiency (vitamin D <30 ng/ml) was common (67%). 25(OH)D levels were related to asthma severity (intermittent: 31.1 ± 13.0 ng/ml, mild: 27.3 ± 11.9 ng/ml, moderate: 26.5 ± 12.0 ng/ml, severe: 24.0 ± 11.8 ng/ml, p = 0.046) and control (controlled: 29.5 ± 12.5 ng/ml, partly controlled 25.9 ± 10.8 ng/ml, uncontrolled: 24.2 ± 11.8 ng/ml, p = 0.030). The frequency of vitamin D insufficiency or deficiency was significantly higher in patients with severe or uncontrolled asthma and was associated with a lower FEV1 (vitamin D <30 vs. ≥30 ng/ml 2.3 ± 0.9 L vs. 2.7 ± 1.0 L, p = 0.006), higher levels of exhaled NO (45 ± 46 ppb vs. 31 ± 37 ppb, p = 0.023), a higher BMI (28.3 ± 6.2 vs. 25.1 ± 3.9, p < 0.001), and sputum eosinophilia (5.1 ± 11.8% vs. 0.5 ± 1.0%, p = 0.005). The use of oral corticosteroids or sputum eosinophilia was associated with a 20% or 40% higher risk of vitamin D insufficiency or deficiency.

Conclusions

25(OH)D levels below 30 ng/ml are common in adult asthma and most pronounced in patients with severe and/or uncontrolled asthma, supporting the hypothesis that improving suboptimal vitamin D status might be effective in prevention and treatment of asthma.     

Increased levels of soluble interleukin-6 receptor and CCL3 in COPD sputum

Background

COPD patients have increased numbers of macrophages and neutrophils in the lungs. Interleukin-6 (IL-6) trans-signaling via its soluble receptor sIL-6R, governs the influx of innate immune cells to inflammatory foci through regulation of the chemokine CCL3. We hypothesized that there would be enhanced levels of IL-6, sIL-6R and CCL3 in COPD sputum.

Methods

59 COPD patients, 15 HNS and 15 S underwent sputum induction and processing with phosphate buffered saline to obtain supernatants for IL-6, sIL-6R and CCL3 analysis. Cytoslides were produced for differential cell counting and immunocytochemistry (COPD; n = 3) to determine cell type surface expression of the CCL3 receptors CCR5 and CCR1.

Results

COPD patients expressed higher levels (p < 0.05) of sIL-6R and CCL3 compared to controls (sIL-6R medians pg/ml: COPD 166.4 vs S 101.1 vs HNS 96.4; CCL3 medians pg/ml: COPD 117.9 vs S 0 vs HNS 2.7). COPD sIL-6R levels were significantly correlated with sputum neutrophil (r = 0.5, p < 0.0001) and macrophage (r = 0.3, p = 0.01) counts. Immunocytochemical analysis revealed that CCR5 and CCR1 were exclusively expressed on airway macrophages.

Conclusion

Enhanced airway generation of sIL-6R may promote IL-6 trans-signaling in COPD. Associated upregulation of CCL3 may facilitate the recruitment of macrophages into the airways by ligation of CCR1 and CCR5.

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Serum tryptase detected during acute coronary syndrome is significantly related to the development of major adverse cardiovascular events after 2?years

Background

One of the greatest challenges in cardiovascular medicine is to define the best tools for performing an accurate risk stratification for the recurrence of ischemic events in acute coronary syndrome (ACS) patients.

Methods

We followed 65 ACS patients enrolled in a previous pilot study for 2 years after being discharged, focusing on the occurrence of major adverse cardiovascular events (MACE).The relationship between serum tryptase levels on admission, SYNergy between percutaneous coronary intervention with the TAXUS drug-eluting stent and the cardiac surgery score (SX-score), cardiovascular complexity and MACE at 2 years follow-up were analyzed.

Results

The ACS population was divided in two groups: patients with MACE (n = 23) and patients without MACE (n = 42).The tryptase measurement at admission (T0) and at discharge (T3) and SX-score were higher in patients who experienced MACE than in those without (p = 0.0001, p < 0.0001 and p = 0.006, respectively). Conversely, we found no significant association between MACE and C-reactive protein (CRP), and between MACE and maximum level of high-sensitivity troponin (hs-Tn) values.Among all patients with MACE, 96% belonged to the group that presented with cardiovascular complexity at the beginning of ACS index admission (p < 0.0001).The predictive accuracy of serum tryptase for MACE at follow up set at the cut-off point of 4.95 ng/ml at T0 and of 5.2 ng/ml at T3. Interestingly, patients with both the above cut-off tryptase values at T0 and at T3 presented a 1320% increase in the odds of developing MACE (p < 0.0001).

Conclusion

In ACS patients, serum tryptase measured during index admission is significantly correlated to the development of MACE up to 2 years, demonstrating a possible long-term prognostic role of this biomarker.

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Enhanced activity of NLRP3 inflammasome in peripheral blood cells of patients with active rheumatoid arthritis

IntroductionInterleukin-1β (IL-1β) is a major inflammatory cytokine, produced predominantly by innate immune cells through NLRP3-inflammasome activation. Both intrinsic and extrinsic danger signals may activate NLRP3. Genetic variations in NLRP3-inflammasome components have been reported to influence rheumatoid arthritis (RA) susceptibility and severity. We sought to assess the activity of NLRP3-inflammasome in patients with active RA compared to healthy individuals.MethodIntracellular protein expression of NLRP3, ASC, pro- and active caspase-1, pro- and active IL-1β was assessed by immunoblotting both at baseline and upon inflammasome activation. NLRP3 function (IL-1β secretion) was assessed upon priming of TLR2 (Pam(3)CysSK(4), TLR3 (poly(I:C)) or TLR4 (LPS) and ATP sequential treatment. We used caspase inhibitors (casp-1, 3/7 and 8) to assess their contribution to IL-1β maturation. All experiments were performed in whole blood cells.ResultsActive RA patients (n = 11) expressed higher basal intracellular levels of NLRP3 (p < 0.008), ASC (p < 0.003), active caspase-1 (p < 0.02) and pro-IL-1β (p < 0.001). Upon priming with TLR4 (LPS) and ATP, RA-derived cell extracts (n = 7) displayed increased expression of NLRP3 (p < 0.01) and active caspase-1 (p < 0.001). Secreted IL-1β in culture supernatants from whole blood cells activated with TLR4 (LPS) or TLR3 agonist (poly(I:C)) plus ATP was higher in RA patients (n = 20) versus controls (n = 18) (p < 0.02 for both). Caspase-1 inhibition significantly reduced IL-1β secretion induced by all stimuli, whereas caspase-8 inhibition affected only TLR4 and TLR3 cell priming.ConclusionPatients with active RA have increased expression of NLRP3 and NLRP3-mediated IL-1β secretion in whole blood cells upon stimulation via TLR3 and TLR4 but not TLR2. In these patients, IL-1β secretion seems to be predominately driven by caspase-1 and caspase-8. Targeting NLRP3 or downstream caspases may be of benefit in suppressing IL-1β production in RA.     

Self-Assembling Nanoparticles Containing Dexamethasone as a Novel Therapy in Allergic Airways Inflammation

Nanocarriers can deliver a wide variety of drugs, target them to sites of interest, and protect them from degradation and inactivation by the body. They have the capacity to improve drug action and decrease undesirable systemic effects. We have previously developed a well-defined non-toxic PEG-dendritic block telodendrimer for successful delivery of chemotherapeutics agents and, in these studies, we apply this technology for therapeutic development in asthma. In these proof-of-concept experiments, we hypothesized that dexamethasone contained in self-assembling nanoparticles (Dex-NP) and delivered systemically would target the lung and decrease allergic lung inflammation and airways hyper-responsiveness to a greater degree than equivalent doses of dexamethasone (Dex) alone. We found that ovalbumin (Ova)-exposed mice treated with Dex-NP had significantly fewer total cells (2.78±0.44×10⁵ (n = 18) vs. 5.98±1.3×10⁵ (n = 13), P<0.05) and eosinophils (1.09±0.28×10⁵ (n = 18) vs. 2.94±0.6×10⁵ (n = 12), p<0.05) in the lung lavage than Ova-exposed mice alone. Also, lower levels of the inflammatory cytokines IL-4 (3.43±1.2 (n = 11) vs. 8.56±2.1 (n = 8) pg/ml, p<0.05) and MCP-1 (13.1±3.6 (n = 8) vs. 28.8±8.7 (n = 10) pg/ml, p<0.05) were found in lungs of the Dex-NP compared to control, and they were not lower in the Dex alone group. In addition, respiratory system resistance was lower in the Dex-NP compared to the other Ova-exposed groups suggesting a better therapeutic effect on airways hyperresponsiveness. Taken together, these findings from early-stage drug development studies suggest that the encapsulation and protection of anti-inflammatory agents such as corticosteroids in nanoparticle formulations can improve efficacy. Further development of novel drugs in nanoparticles is warranted to explore potential treatments for chronic inflammatory diseases such as asthma.     

Effect of dexamethasone prodrug on inflamed temporomandibular joints in juvenile rats

IntroductionJuvenile idiopathic arthritis (JIA) often causes inflammation of the temporomandibular joint (TMJ) and has been treated with both systemic and intra-articular steroids, with concerns about effects on growing bones. In this study, we evaluated the impact of a macromolecular prodrug of dexamethasone (P-DEX) with inflammation-targeting potential applied systemically or directly to the TMJ.MethodsJoint inflammation was initiated by injecting two doses of complete Freund’s adjuvant (CFA) at 1-month intervals into the right TMJs of 24 growing Sprague–Dawley male rats (controls on left side). Four additional rats were not manipulated. With the second CFA injection, animals received (1) 5 mg of P-DEX intra-articularly (n = 9), (2) 15 mg of P-DEX into the tail vein (n = 7), or (3) nothing in addition to CFA (n = 8). The rats were killed 28 days later and measured by radiography for ramus height (condylar superior to gonion inferior [CsGoInf]), by micro-computed tomography for condylar width (CW) and bone volume/standardized condylar volume (BV/CV), and by histology for retrodiscal inflammatory cells. Inflammation targeting of systemic P-DEX was confirmed by IVIS infrared dye imaging. Inflammation and bone growth were compared between groups using analysis of variance and Pearson’s correlations.ResultsCFA caused a significant reduction in CsGoInf (p < 0.05), but neither route of P-DEX administration had an effect on CsGoInf or CW at CFA injection sites. BV/CV was significantly reduced in both inflamed and control condyles as a result of either steroid application (p < 0.05). The inflammatory infiltrate was overwhelmingly lymphocytic, comprising 16.4 ± 1.3 % of the field in CFA alone vs. <0.01 % lymphocytes in contralateral controls (p < 0.0001). Both P-DEX TMJ (10.1 ± 1.2 %) and systemic P-DEX (8.9 ± 1.7 %) reduced lymphocytes (p < 0.002). The total area of inflammatory infiltrate was significantly less in the systemic injection group than in the group that received CFA injections alone (2.6 ± 1.5 mm² vs. 8.0 ± 1.3 mm²; p = 0.009), but not in the group that received intra-articular P-DEX (8.8 ± 1.2 mm²).ConclusionsHigh-dose systemic administration of inflammation-targeting P-DEX is more effective than an intra-articular injection in reducing TMJ inflammation, but both routes may affect TMJ bone density.     

High mobility group box 1 levels in large vessel vasculitis are not associated with disease activity but are influenced by age and statins

IntroductionTakayasu arteritis (TA) and giant cell arteritis (GCA) are large vessel vasculitides (LVV) that usually present as granulomatous inflammation in arterial walls. High mobility group box 1 (HMGB1) is a nuclear protein that acts as an alarmin when released by dying or activated cells. This study aims to evaluate whether serum HMGB1 can be used as a biomarker in LVV.MethodsTwenty-nine consecutive TA patients with 29 healthy controls (HC) were evaluated in a cross-sectional study. Eighteen consecutive GCA patients with 16 HC were evaluated at the onset of disease and some of them during follow-up. Serum HMGB1 levels were measured by enzyme-linked immunosorbent assay.ResultsIn GCA patients at disease onset mean serum HMGB1 levels did not differ from HC (5.74 ± 4.19 ng/ml vs. 4.17 ± 3.14 ng/ml; p = 0.230). No differences in HMGB1 levels were found between GCA patients with and without polymyalgia rheumatica (p = 0.167), ischemic manifestations (p = 0.873), systemic manifestations (p = 0.474) or relapsing disease (p = 0.608). During follow-up, no significant fluctuations on serum HMGB1 levels were observed from baseline to 3 months (n = 13) (p = 0.075), 12 months (n = 6) (p = 0.093) and at the first relapse (n = 4) (p = 0.202). Serum HMGB1 levels did not differ between TA patients and HC [1.19 (0.45–2.10) ng/ml vs. 1.46 (0.89–3.34) ng/ml; p = 0.181] and no difference was found between TA patients with active disease and in remission [1.31 (0.63–2.16) ng/ml vs. 0.75 (0.39–2.05) ng/ml; p = 0.281]. HMGB1 levels were significantly lower in 16 TA patients on statins compared with 13 patients without statins [0.59 (0.29–1.46) ng/ml vs. 1.93 (0.88–3.34) ng/ml; p = 0.019]. Age was independently associated with higher HMGB1 levels regardless of LVV or control status.ConclusionsPatients with TA and GCA present similar serum HMGB1 levels compared with HC. Serum HMGB1 is not useful to discriminate between active disease and remission. In TA, use of statins was associated with lower HMGB1 levels. HMGB1 is not a biomarker for LVV.     

Early cartilage abnormalities at the hip are associated with obesity and body composition measures – a 3.0T MRI community-based study

IntroductionAlthough obesity is a risk factor for hip osteoarthritis (OA), the role of body composition, if any, is unclear. This study examines whether the body mass index (BMI) and body composition are associated with hip cartilage changes using magnetic resonance imaging (MRI) in community-based adults.Methods141 community-based participants with no clinical hip disease, including OA, had BMI and body composition (fat mass and fat free mass) measured at baseline (1990 to 1994), and BMI measured and 3.0 T MRI performed at follow-up (2009–2010). Femoral head cartilage volume was measured and femoral head cartilage defects were scored in the different hip regions.ResultsFor females, baseline BMI (β = −26 mm³, 95% Confidence interval (CI) -47 to −6 mm³, p = 0.01) and fat mass (β = −11 mm³, 95% CI −21 to −1 mm³, p = 0.03) were negatively associated with femoral head cartilage volume. Also, while increased baseline fat mass was associated with an increased risk of cartilage defects in the central superolateral region of the femoral head (Odds Ratio (OR) = 1.08, 95% CI 1.00–1.15, p = 0.04), increased baseline fat free mass was associated with a reduced risk of cartilage defects in this region (OR = 0.82, 95% CI 0.67–0.99; p = 0.04). For males, baseline fat free mass was associated with increased femoral head cartilage volume (β = 40 mm³, 95% CI 6 to 74 mm³, p = 0.02).ConclusionsIncreased fat mass was associated with adverse hip cartilage changes for females, while increased fat free mass was associated with beneficial cartilage changes for both genders. Further work is required to determine whether modifying body composition alters the development of hip OA.     

The revised role of TGF-β in aortic aneurysms in Marfan syndrome

BackgroundRecently, we demonstrated that losartan reduced the aortic root dilatation rate (AoDR) in adults with Marfan syndrome (MFS); however, responsiveness was diverse. The aim was to determine the role of transforming growth factor-β (TGF-β) as therapeutic biomarker for effectiveness of losartan on AoDR.MethodsBaseline plasma TGF-β levels of 22 healthy controls and 99 MFS patients, and TGF-β levels after 1 month of losartan treatment in 42 MFS patients were measured. AoDR was assessed by magnetic resonance imaging at baseline and after 3 years of follow-up.ResultsPatients with MFS had higher TGF-β levels compared with healthy controls (121 pg/ml versus 54 pg/mL, p = 0.006). After 1 month of therapy, losartan normalised the TGF-β level in 15 patients (36%); the other 27 patients (64%) showed a significant increase of TGF-β. After 3 years of losartan therapy, patients with a decrease in TGF-β had significantly higher AoDR compared with patients with increased TGF-β (1.5 mm/3 years versus 0.5 mm/3 years, p = 0.04). Patients showing a decrease in TGF-β after losartan therapy had significantly elevated baseline TGF-β levels compared with patients with increased TGF-β (189 pg/ml versus 94 pg/ml, p = 0.05).ConclusionPatients responding to losartan therapy with a reduction of the plasma TGF-β level had higher baseline TGF-β levels and a higher AoDR. Most likely, TGF-β levels may be considered to be a readout of the disease state of the aorta. We propose that increased angiotensin II is the initiator of aorta dilatation and is responsible for increased TGF-β levels in MFS. The concept of TGF-β as initiator of aortic dilatation in MFS patients should be nuanced.