A study on vascular endothelial growth factor and endothelin-1 in patients with extra-articular involvement of rheumatoid arthritis

Serum netrin-1 levels are high in Rheumatoid arthritis associated interstitial lung disease

BACKGROUND

Recent data show that netrin-1 has a role in development of pulmonary fibrosis. This study was aimed to investigate serum netrin-1 level and its relation to interstitial lung disease(ILD) in patients with rheumatoid arthritis (RA).

METHOD

42 RA patients with RA-ILD, 58 RA patients without RA-ILD (RA non-ILD group), and 61 healthy volunteers were included in this study. The modified DAS28-ESR score was used to calculate disease activity in RA patients. Using the quantitative immunoassay method, Serum netrin-1 levels were measured with an ELISA kit (Catalog number: E-EL-H2328; lab science, lot number: GZWTKZ5SWK, Texas, USA).

RESULTS

The median value of netrin-1 was found to be significantly higher in the RA-ILD group (82.9 [59.9-124]) compared to both the RA non-ILD group(52.9 [49.5-73.1])(B = -0.006, OR = 0.994, CI 95 %=0.989-0.999, P = 0.018) and the control group(53.5 [49.5-87.5]) (B: -0.005, OR: 0.994, CI 95 %: 0.990-0.999, p: 0.022). A cut-off value of 61.78 for netrin-1 was found to have a sensitivity of 73.8 % and a specificity of 69 % for the diagnosis of RA-ILD (AUC [95 %Cl] = 0.771 [0.679-0.862], p < 0.0001).It was found that high serum netrin-1 level was strongly associated with the RA-usual interstitial pneumonia(UIP) pattern and poorly related to the RA-nonspecific interstitial pneumonia(NSIP) pattern compared to the RA non-ILD group.

CONCLUSIONS

Netrin-1 is elevated in the serum of patients with RA-ILD, especially in the UIP pattern. Netrin-1 may be a potential candidate for predicting the development of RA-ILD that should be investigated in the pathophysiological and therapeutic fields..

Relevance of circulating markers of endothelial activation for cardiovascular risk assessment in rheumatoid arthritis: a narrative review

Rheumatoid arthritis (RA) is associated with excessive cardiovascular mortality secondary to premature atherosclerosis, in which endothelial activation (EA) plays a central role. EA is characterized by loss of vascular integrity, expression of leucocyte adhesion molecules, transition from antithrombotic to prothrombotic phenotype, cytokines production, shedding of membrane microparticles and recruitment of endothelial progenitor cells. As EA is an early event in atherogenesis, circulating markers of EA are putative markers of vascular pathology and cardiovascular (CV) risk. After a presentation of biology of EA, the present review analyzed the available data regarding changes in EA markers in RA in link with the vascular pathology and CV events, discussed their relevance as biomarkers of CV risk and proposed future directions.

Serum MMP-9, SP-D, and VEGF levels reflect the severity of connective tissue disease-associated interstitial lung diseases

BACKGROUND

Interstitial lung disease (ILD) is a common pulmonary complication of connective tissue disease (CTD). This study aims to evaluate the clinical diagnostic value of matrix metalloproteinase-9 (MMP-9), surfactant protein-D (SP-D), and vascular endothelial growth factor (VEGF) as potential biomarkers for CTD-ILD.

METHODS

This research included 33 CTD-ILD patients, 31 CTD patients without ILD, and 24 healthy control subjects. Then, the value of biomarkers for the diagnosis and evaluation of CTD-ILD was assessed through high-resolution computed tomography (HRCT) findings and pulmonary function test (PFT) parameters.

RESULTS

The serum MMP-9, SP-D, and VEGF levels in the CTD-ILD group were higher than those in the CTD-NILD group and healthy group. The ROC curve indicates that VEGF has good to excellent diagnostic performance in diagnosing CTD-ILD, the cut-off that best optimizes sensitivity and specificity in diagnosing CTD-ILD is 277.60 pg/ml (sensitivity, 87.9%; specificity, 83.6%), with an area under the curve (AUC) of 0.905 (95% confidence interval (CI) 0.842-0.968); The ROC curve for MMP-9 suggests this biomarker is fair for diagnosis of CTD-ILD(sensitivity, 81.8%; specificity, 81.8%), with an AUC of 0.867 (95% CI 0.784-0.950), but SP-D only provided lower specificity with higher sensitivity in diagnosing CTD-ILD(sensitivity, 90.9%; specificity, 40.0%). The different serum biomarkers are more specific and sensitive when combined to diagnose ILD. The semiquantitative score for the degree of ILD severity on HRCT was positively correlated with SP-D and VEGF levels (r = 0.461, P = 0.007; r = 0.362, P = 0.039), and serum MMP-9 levels were elevated in the UIP subgroup compared to the non-UIP subgroup. The percentage of diffusing capacity of the lung for carbon monoxide (DLco) (% predicted) had a negative correlation with the SP-D level (r = - 0.407, P = 0.044) and a statistically negative correlation between MMP-9 and the forced vital capacity (FVC) (r = - 0.451, P = 0.024).

CONCLUSIONS

Serum MMP-9, SP-D, and VEGF levels may have clinical value in screening and evaluating the severity of CTD-ILD.

Exploring the pivotal role of endothelin in rheumatoid arthritis

A chronic inflammatory disorder, rheumatoid arthritis (RA) is an autoimmune and systemic disease characterized by progressive and prolonged destruction of joints. This results in increased mortality, physical disability and destruction. Cardiovascular disorders are one of the primary causes of mortality in patients with RA. It is multifactorial in nature and includes genetic, environmental and demographic factors which contribute to the severity of disease. Endothelin-1 (ET-1) is a peptide which acts as a potent vasoconstrictor and is generated through vascular smooth muscle and endothelial cells. Endothelins may be responsible for RA, as under certain circumstances they produce reactive oxygen species which further promote the production of pro-inflammatory cytokines. This enhances the production of superoxide anion, which activates pro-inflammatory cytokines, resulting in RA. The aim of this review is to elucidate the role of endothelin in the progression of RA. This review also summarizes the natural and synthetic anti-inflammatory drugs which have provided remarkable insights in targeting endothelin.

Association of Circulating Vascular Endothelial Growth Factor Levels With Autoimmune Diseases: A Systematic Review and Meta-Analysis

Background

Autoimmune diseases (ADs) are characterized by immune-mediated tissue damage, in which angiogenesis is a prominent pathogenic mechanism. Vascular endothelial growth factor (VEGF), an angiogenesis modulator, is significantly elevated in several ADs including rheumatoid arthritis (RA), systemic sclerosis (SSc), and systemic lupus erythematosus (SLE). We determined whether circulating VEGF levels were associated with ADs based on pooled evidence.

Methods

The analyses included 165 studies from the PubMed, EMBASE, Cochrane Library, and Web of Science databases and fulfilled the study criteria. Comparisons of circulating VEGF levels between patients with ADs and healthy controls were performed by determining pooled standard mean differences (SMDs) with 95% confidence intervals (CIs) in a random-effect model using STATA 16.0. Subgroup, sensitivity, and meta-regression analyses were performed to determine heterogeneity and to test robustness.

Results

Compared with healthy subjects, circulating VEGF levels were significantly higher in patients with SLE (SMD 0.84, 95% CI 0.25-1.44, P = 0.0056), RA (SMD 1.48, 95% CI 0.82-2.15, P <0.0001), SSc (SMD 0.56, 95% CI 0.36-0.75, P <0.0001), Behcet's disease (SMD 1.65, 95% CI 0.88-2.41, P <0.0001), Kawasaki disease (SMD 2.41, 95% CI 0.10-4.72, P = 0.0406), ankylosing spondylitis (SMD 0.78, 95% CI 0.23-1.33, P = 0.0052), inflammatory bowel disease (SMD 0.57, 95% CI 0.43-0.71, P <0.0001), psoriasis (SMD 0.98, 95% CI 0.62-1.34, P <0.0001), and Graves' disease (SMD 0.69, 95% CI 0.20-1.19, P = 0.0056). Circulating VEGF levels correlated with disease activity and hematological parameters in ADs.

Conclusion

Circulating VEGF levels were associated with ADs and could predict disease manifestations, severity and activity in patients with ADs.

Systematic Review Registration

PROSPERO, identifier CRD42021227843.

Handheld dermatoscopy as an easy-to-use capillaroscopic instrument in rheumatoid arthritis: a cross-sectional study

Background/aim

Nailfold video capillaroscopy is considered as a reliable method for evaluating peripheral microangiopathy in rheumatologic diseases. In this study, we aimed to demonstrate the utility of handheld dermatoscopy as an easy-to-use nailfold capillaroscopic instrument in patients with rheumatoid arthritis.

Materials and methods

This cross-sectional study included patients with rheumatoid arthritis and healthy subjects. A handheld dermatoscopic examination of proximal nail fold was performed in each subject. The possible correlation of capillaroscopic findings with disease activity was evaluated using the disease activity score 28 (DAS28).

Results

A total of 59 patients with rheumatoid arthritis and 60 healthy subjects were enrolled in the study. The presence of capillaryenlargement, avascular areas, capillary deformities, and capillary vascular anomalies in the group of patients showed a statistically significant difference when compared with the healthy subjects. No correlation was found between the nail fold capillaroscopic findings and DAS28 score.

Conclusion

Hand-held dermatoscopy seems to be a useful technique in the evaluation of nail fold capillary changes. We suggest that in patients with rheumatoid arthritis, when capillaroscopic examination is needed, it can be evaluated using handheld dermatoscopy. Selected patients who showed findings using this method can be further examined with classical capillaroscopy to obtain more quantitative data.

ET-traps offer a potential therapeutic tool for use in different autoimmune diseases

Research shows that endothelin (ET)-traps are a potential therapy for diabetes. Given that type 1 diabetes mellitus (T1DM) is an autoimmune disorder, ET-traps could also have an efficacious, therapeutic effect on other autoimmune diseases associated with pathologically elevated ET-1. Here, we describe those different autoimmune diseases that might benefit from a tool such as ET-traps, which potently sequester these elevated levels of ET-1. We also discuss the current use of ET receptor (ETR) antagonists and the associated adverse effects, and how ET-traps are associated with no toxicity and potentially offer a superior alternative. ET-traps could be used against different autoimmune diseases and, therefore, are a novel therapeutic tool for such conditions.

CONNECTIVE TISSUE DISEASES: FOCUS ON MICROCIRCULATORY BED

Background. A microcirculatory bloodstream is a target, source and reason of the pathological process in patients with systemic connective tissue diseases. Objectives. This study is focused on meta-analyses of biopsy material of skin flaps harvested from patients’ fingers to identify specific morphological changes. Methods. A retrospective analysis of the medical records of 39 examinees with systemic sclerosis (SSc), 45 with Systemic Lupus Erythematosus (SLE), and 45 with rheumatoid arthritis (RA) was performed. The condition of peripheral hemodynamics was examined with longitudinal rheovasography of arms and legs. Endothelin-1 (ЕТ1) concentration was evaluated by immunoenzymatic method. We assessed other results of clinical and laboratory tests to compare them with morphological changes of the microcirculatory bed. Results. Most patients involved suffered from abnormal peripheral hemodynamics. It was revealed that kidneys, lungs or heart were damaged more frequently in the patients with peripheral blood circulation disorders, which were the most significant in the patients with SSc (p<0.05). Disorders of peripheral blood flow were exacerbated in case of lengthening of the disease course. Concentration of ЕТ1 was relevantly higher in the patients with peripheral blood flow disorders. Number of pathologic capillaries was the highest in the SSc patients. Conclusions. In terms of integral estimation, extremely significant changes of microcirculatory bloodstream were evidenced in the patients with SSc. However, some morphometric peculiarities were revealed in the patients without peripheral blood flow disorders. Thus, normal rheovasography did not exclude any microcirculation disorders.

Nailfold capillaroscopic changes in patients with chronic viral hepatitis

BACKGROUND

Nailfold capillaroscopy is a highly sensitive, inexpensive, simple, safe, and noninvasive technique used in the investigation of the microcirculation. However, the diseases having a vasculitic component can cause changes in the nailfold capillaries like viral hepatitis, the microvascular characteristics of the nailfold area in HBV and HCV infected individuals have not been systematically investigated. In this study, we investigated possible dermoscopic differences in the vascular appearance of the nailfold capillaries and their association with the disease's clinical status.

METHOD

A hundred and forty-seven patients and 147 healthy controls were enrolled in this study. The patients' group consisted of chronic viral hepatitis B (CHB: 54 cases), chronic hepatitis C (CHC: 36 cases) and carrier of hepatitis B virus infection (CRHB: 57 cases). Nailfold capillaroscopy was performed using a digital dermoscope (Molemax II, X30). All capillaroscopy images were evaluated for capillary density, capillary loop enlargement, capillary tortuosities, branching vessels, micro hemorrhages, avascular areas and splinter hemorrhages, and routine laboratory examinations of all patients were performed.

RESULTS

Statistical differences in all of the categories of capillary morphology were prominent between the capillary abnormalities of Hepatitis B and the control group, also the capillary abnormality was significant between hepatitis C and the control group (p < 0.01). None of the 147 healthy control had any nailfold capillary changes. There was a significant difference between the CHB-Control and CRHB-Control groups in all of the capillaroscopic changes (p < 0.01). The avascular area was also the most common finding in Hepatitis C and Hepatitis B infected individuals, and capillary dilatation (CD), capillary tortuosity (CT) and capillary enlargement (CE) were the major nailfold capillary changes in both of two diseases.

CONCLUSION

Nailfold capillary abnormalities are one of the extrahepatic dermatologic finding which could be a sign of the endothelial tissue damage in chronic viral hepatitis, we do not have any data about the effects of these two usual infections on the nailfold capillary morphology. This is the first study evaluating the microvasculature abnormalities of the nailfold capillaries in hepatitis B and hepatitis C infected individuals by capillaroscopic examination.

Correlation between circulating VEGF levels and disease activity in rheumatoid arthritis: a meta-analysis

OBJECTIVE

To systematically review evidence regarding the relationship between circulating vascular endothelial growth factor (VEGF) levels and rheumatoid arthritis (RA), the correlation between serum VEGF levels and RA activity, and the association between VEGF polymorphisms and RA susceptibility.

METHODS

We conducted a meta-analysis of the serum/plasma VEGF levels in patients with RA and controls, the correlation coefficients between the circulating VEGF levels and disease activity in patients with RA, and the association between VEGF -2578 A/C, -634 C/G, +936 T/C, and -1154 A/G polymorphisms and the risk for RA.

RESULTS

In total, 13 studies including 2508 patients with RA and 2489 controls were included. Meta-analysis revealed that VEGF level was significantly higher in the RA than in the control group (standard mean difference [SMD] = 1.480, 95% confidence interval [CI] = 0.71-2.241, p = 1.4 × 10^-4). Stratification by adjustment for age and gender revealed significantly higher VEGF levels for the adjustment and non-adjustment groups in the RA group (SMD = 1.360, 95% CI = 0.445-2.276, p = 0.004; SMD = 1.557, 95% CI = 0.252-2.861, p = 0.019, respectively). Meta-analysis of correlation coefficients showed a significantly positive correlation between circulating VEGF levels and disease activity in RA, and between circulating VEGF and C‑reactive protein levels. However, no association was found between RA and the VEGF -2578 A/C, -634 C/G, +936 T/C, and -1154 A/G polymorphisms.

CONCLUSION

Our meta-analysis revealed significantly higher circulating VEGF levels in patients with RA and a positive correlation between VEGF levels and disease activity in RA, but no association between the VEGF -2578 A/C, -634 C/G, +936 T/C, and -1154 A/G polymorphisms and the development of RA.

VEGF (Vascular Endothelial Growth Factor) and Fibrotic Lung Disease

Interstitial lung disease (ILD) encompasses a group of heterogeneous diseases characterised by varying degrees of aberrant inflammation and fibrosis of the lung parenchyma. This may occur in isolation, such as in idiopathic pulmonary fibrosis (IPF) or as part of a wider disease process affecting multiple organs, such as in systemic sclerosis. Anti-Vascular Endothelial Growth Factor (anti-VEGF) therapy is one component of an existing broad-spectrum therapeutic option in IPF (nintedanib) and may become part of the emerging therapeutic strategy for other ILDs in the future. This article describes our current understanding of VEGF biology in normal lung homeostasis and how changes in its bioavailability may contribute the pathogenesis of ILD. The complexity of VEGF biology is particularly highlighted with an emphasis on the potential non-vascular, non-angiogenic roles for VEGF in the lung, in both health and disease.

Quercetin attenuates zymosan-induced arthritis in mice

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by articular lesions, recruitment of inflammatory cells and increased levels of pro-inflammatory cytokine. The intra-articular administration of zymosan is an experimental model that promotes inflammatory parameters resembling RA. Therefore, this model was used to investigate the efficacy of quercetin as a treatment of articular inflammation. Treatment with quercetin dose-dependently reduced zymosan-induced hyperalgesia, articular edema and the recruitment of neutrophils to the knee joint cavity. Histological analysis confirmed that quercetin inhibited zymosan-induced arthritis. The treatment with quercetin also inhibited zymosan-induced depletion of reduced glutathione (GSH) levels, TNFα and IL-1β production, and gp91^phox, prepro-endothelin-1 (preproET-1), and cyclooxygenase-2 mRNA expression. These molecular effects of quercetin were related to the inhibition of the nuclear factor kappa-B and induction of Nuclear factor erythroid 2- related factor (Nrf2)/home oxygenase (HO-1) pathway. Thus, quercetin exerted anti-inflammatory, analgesic and antioxidant effects in experimental arthritis, suggesting quercetin is a possible candidate for arthritis treatment.

Nailfold capillaroscopy in 430 patients with rheumatoid arthritis

Background:

Microvascular changes are one of the first obvious steps in numerous inflammatory diseases such as rheumatoid arthritis (RA). Nailfold video capillaroscopy (NFC) is an easy, reliable and safe method for evaluating peripheral microangiopathy. The objective of this study was to examine nailfold microcirculation in RA patients, assess morphological and structural changes quantitatively and qualitatively, and recognize useful changes.

Methods:

A total of 430 patients diagnosed with RA were examined in a period of 4 years. NFC was performed on all fingers of both hands in each patient. Different parameters indicating microvascular changes were detected and analyzed; such as microvascular architecture, capillary distribution disturbances, capillary morphology, capillary density, efferent/afferent limb ratio, subpapillary venular plexus and morphological abnormalities. The obtained results were categorized into normal pattern, nonspecific morphological abnormality and scleroderma pattern.

Results:

The mean age of participants was 51.03±14.54 (19-87 years) that consisted of 359 females and 71 males. Based on the findings, angiogenesis (74.7%) was the most pathological condition observed after tortuosity (99.5%). 7.2% and 20.9% of patients were categorized into normal and scleroderma pattern group, respectively. Among morphological abnormalities, angiogenesis, isolated enlarged loop, irregular enlarged loop and architectural derangement were significantly more frequent in scleroderma than normal pattern (p<0.001).

Conclusion:

NFC may play an important role in monitoring RA disease and patients’ follow-up. Therefore, in our opinion it could be considered in the course and follow-up of rheumatoid arthritis.

Association between endothelin‑1 and fibromyalgia syndrome

Fibromyalgia syndrome (FMS) is characterized by widespread chronic musculoskeletal pain, stiffness and pressure hyperalgesia at soft tissue tender points. Patients with FMS may exhibit a tendency towards cold extremities and cold‑induced vasospasm. Endothelin‑1 (EDN1) is a potent vasoconstrictor that is mainly produced by endothelial cells. The present study aimed to determine whether plasma expression levels avvnd single‑nucleotide polymorphism (SNP; rs1800541) of the EDN1 gene were associated with FMS and/or any of its clinical variables. Plasma EDN1 levels were assessed by ELISA, and SNP genotypes were determined using polymerase chain reaction‑high‑resolution melting curve analysis. Patients with the TG genotype and the G allele may have an elevated risk of FMS. In addition, patients with FMS with the TG genotype and/or T allele exhibited higher plasma EDN1 levels compared with healthy controls. EDN1 levels increased significantly in patients with FMS compared with normal controls. In addition, EDN1 SNP was found to be associated with susceptibility to FMS.

Extra-Articular Symptoms in Constellation with Selected Serum Cytokines and Disease Activity in Spondyloarthritis

Objectives. In this study, we assessed the extra-articular symptoms in constellation with selected serum cytokines and disease activity in spondyloarthritis (SpA). Patients and Methods. We studied 287 SpA patients: 131 had AS, 110 had PsA, and 46 had SAPHO. We assessed extra-articular symptoms in all cases. In 191 SpA patients, we measured serum interleukin-6 (IL-6), interleukin-18 (IL-18), interleukin-23 (IL-23), endothelin-1 (ET-1), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF). Results. Patients with acute anterior uveitis (AAU) had higher VAS (P = 0.0008), BADSDAI (P = 0.0001), ASDAS-ESR (P = 0.04), CRP (P = 0.006), IL-6 (P = 0.02), and IL-18 (P = 0.03) levels. Patients with inflammatory bowel disease (IBD) had higher VAS (P = 0.03), CRP (P = 0.0009), and IL-6 (P = 0.0003) levels. Patients with skin psoriasis had lower VAS (P = 0.001) and BASDAI (P = 0.00007) levels. Patients with psoriatic onycholysis had lower VAS (P = 0.006), BASDAI (P = 0.00001), and CRP (P = 0.02) and higher IL-23 (P = 0.04) levels. Patients with PPP had lower BASDAI (P = 0.04) and higher ET-1 (P = 0.001) levels. Conclusions. SpA patients with increased serum IL-18 and decreased serum ET-1 had an increased risk of extra-articular symptoms. In SpA patients, increased disease activity was associated with an increased risk of AAU and IBD and a decreased risk of skin psoriasis, psoriatic onycholysis, and PPP.

Relationship between VEGF Gene Polymorphisms and Serum VEGF Protein Levels in Patients with Rheumatoid Arthritis

BACKGROUND

Rheumatoid arthritis (RA) is one of the chronic autoimmune diseases, with genetic and environmental predisposition, and synovial angiogenesis is considered to be a notable stage in its pathogenesis. Angiogenesis or vascular proliferation has been suggested to be a pivotal mechanism involved in both inflammation/immune activation and joint invasion and destruction. RA may be considered an "angiogenic disease" because it is associated with active tissue neovascularization. Vascular endothelial growth factor (VEGF) promotes vascular permeability, regulates angiogenesis, endothelial cell proliferation and migration, chemotaxis, and capillary hyper permeability and therefore is involved in the development of inflammation. VEGF is the most potent proangiogenic molecule promoting the angiogenic phenotype of RA and is upregulated in RA.

OBJECTIVES

The aim of the study was to identify functional VEGF variants and their possible association with VEGF expression, susceptibility to and severity of RA.

METHODS

581 RA patients and of 341 healthy individuals were examined for -1154 A/G, -2578 A/C VEGF gene polymorphisms by PCR-RFLP method and for -634 G/C VEGF gene polymorphisms by TaqMan SNP genotyping assay. Serum VEGF levels in RA patients and controls were measured by ELISA.

RESULTS

The -1154 A/G VEGF gene polymorphism under the codominant, recessive (AA+AG vs. GG) and dominant (AA vs. AG+GG) models were associated with RA (p = 0.0009; p = 0.004; p = 0.017, respectively). VEGF -2578 A/C revealed differences in the case-control distribution in codominant, recessive, dominant and overdominant models (all p<0.0001). Furthermore, the -634 G/C VEGF gene SNP was not correlated with susceptibility to RA in Polish population. The genotype-phenotype analysis showed significant association between the VEGF -1154 A/G and -634 G/C and mean value of the hemoglobin (all p = 0.05), additionally they relevated that the number of women with the polymorphic allele -2578 C was lower than the number of women with wild type allele -2578A (p = 0.006). Serum VEGF levels were significantly higher in RA patients than in control groups (both p = 0,0001).

CONCLUSION

Present findings indicated that VEGF genetic polymorphism as well as VEGF protein levels may be associated with the susceptibility to RA in the Polish population.

The emerging role of endothelin-1 in the pathogenesis of subchondral bone disturbance and osteoarthritis

Mounting evidence suggests reconceptualizing osteoarthritis (OA) as an inflammatory disorder. Trauma and obesity, the common risk factors of OA, could trigger the local or systemic inflammatory cytokines cascade. Inflammatory bone loss has been well documented; yet it remains largely unknown about the link between the inflammation and hypertrophic changes of subchondral bone seen in OA, such as osteophytosis and sclerosis. Amid a cohort of inflammatory cytokines, endothelin-1 (ET-1) could stimulate the osteoblast-mediated bone formation in both physiological (postnatal growth of trabecular bone) and pathological conditions (bone metastasis of prostate or breast cancer). Also, ET-1 is known as a mitogen and contributes to fibrosis in various organs, e.g., skin, liver, lung, kidney heart and etc., as a result of inflammatory or metabolic disorders. Subchondral bone sclerosis shared the similarity with fibrosis in terms of the overproduction of collagen type I. We postulated that ET-1 might have a hand in the subchondral bone sclerosis of OA. Meanwhile, ET-1 was also able to stimulate the production of matrix metalloproteinase (MMP)-1 and 13 by articular chondrocytes and synoviocytes, by which it might trigger the enzymatic degradation of articular cartilage. Taken together, ET-1 signaling may play a role in destruction of bone-cartilage unit in the pathogenesis of OA; it warrants further investigations to potentiate ET-1 as a novel diagnostic biomarker and therapeutic target for rescue of OA.

Type I IFNs as biomarkers in rheumatoid arthritis: towards disease profiling and personalized medicine

RA (rheumatoid arthritis) is a chronic rheumatic condition hallmarked by joint inflammation and destruction by self-reactive immune responses. Clinical management of RA patients is often hampered by its heterogeneous nature in both clinical presentation and outcome, thereby highlighting the need for new predictive biomarkers. In this sense, several studies have recently revealed a role for type I IFNs (interferons), mainly IFNα, in the pathogenesis of a subset of RA patients. Genetic variants associated with the type I IFN pathway have been linked with RA development, as well as with clinical features. Moreover, a role for IFNα as a trigger for RA development has also been described. Additionally, a type I IFN signature has been associated with the early diagnosis of RA and clinical outcome prediction in patients undergoing biological drug treatment, two challenging issues for decision-making in the clinical setting. Moreover, these cytokines have been related to endothelial damage and vascular repair failure in different autoimmune disorders. Therefore, together with chronic inflammation and disease features, they could probably account for the increased cardiovascular disease morbidity and mortality of these patients. The main aim of the present review is to provide recent evidence supporting a role for type I IFNs in the immunopathology of RA, as well as to analyse their possible role as biomarkers for disease management.

Role of heparin on serum VEGF levels and local VEGF contents in reducing the severity of experimental severe acute pancreatitis in rats

OBJECTIVE

The aims of this study were to examine the effects of prophylactic heparin treatment during taurocholate-induced pancreatitis in rats and its impact on serum VEGF levels and local VEGF contents within the pancreas.

METHODS

Severe acute pancreatitis (SAP) was induced by injecting 4% sodium taurocholate into the pancreatic duct. Heparin at a dose of 150 IU/kg s.c. was administered 30 min before the operation. The rats were sacrificed 1 h, 3 h, 6 h and 12 h (n = 5 per time point) after the onset of pancreatitis. The severity of pancreatitis, serum VEGF levels and local VEGF contents were evaluated with and without heparin pretreatment.

RESULTS

The serum VEGF levels increased at an early phase of pancreatitis, and the highest level was found at 12 h after inducing pancreatitis. The gray value of the local VEGF showed a remarkable increase from the onset of the pancreatitis. However, the gray value of VEGF did not show an increase over time but maintained a high level during the entire process. Prophylactic heparin treatment significantly improved the morphologic changes, myeloperoxidase (MPO), TNF-α and malondialdehyde (MDA) activities. Meanwhile, it decreased the serum VEGF levels and the contents of VEGF within the pancreatic tissue.

CONCLUSIONS

The present study suggests that prophylactic heparin ameliorates the severity of taurocholate-induced pancreatitis via its anti-inflammatory properties. These protective effects may be partly due to decreasing serum VEGF levels and VEGF contents within the pancreas.

Lipoxin A(4) attenuates zymosan-induced arthritis by modulating endothelin-1 and its effects

BACKGROUND AND PURPOSE

Lipoxin A(4) (LXA(4)) is a lipid mediator involved in the resolution of inflammation. Increased levels of LXA(4) in synovial fluid and enhanced expression of the formyl peptide receptor 2/lipoxin A(4) receptor (FPR2/ALX) in the synovial tissues of rheumatoid arthritis patients have been reported. Endothelins (ETs) play a pivotal pro-inflammatory role in acute articular inflammatory responses. Here, we evaluated the anti-inflammatory role of LXA(4), during the acute phase of zymosan-induced arthritis, focusing on the modulation of ET-1 expression and its effects.

EXPERIMENTAL APPROACH

The anti-inflammatory effects of LXA(4), BML-111 (agonist of FPR2/ALX receptors) and acetylsalicylic acid (ASA) pre- and post-treatments were investigated in a murine model of zymosan-induced arthritis. Articular inflammation was assessed by examining knee joint oedema; neutrophil accumulation in synovial cavities; and levels of prepro-ET-1 mRNA, leukotriene (LT)B(4), tumour necrosis factor (TNF)-α and the chemokine KC/CXCL1, after stimulation. The direct effect of LXA(4) on ET-1-induced neutrophil activation and chemotaxis was evaluated by shape change and Boyden chamber assays respectively.

KEY RESULTS

LXA(4), BML-111 and ASA administered as pre- or post-treatment inhibited oedema and neutrophil influx induced by zymosan stimulation. Zymosan-induced preproET-1 mRNA, KC/CXCL1, LTB(4) and TNF-α levels were also decreased after LXA(4) pretreatment. In vitro, ET-1-induced neutrophil chemotaxis was inhibited by LXA(4) pretreatment. LXA(4) treatment also inhibited ET-1-induced oedema formation and neutrophil influx into mouse knee joints.

CONCLUSION AND IMPLICATION

LXA(4) exerted anti-inflammatory effects on articular inflammation through a mechanism that involved the inhibition of ET-1 expression and its effects.

Lack of an association of GNB3 C825T polymorphism and blood pressure in patients with rheumatoid arthritis

G-protein beta 3 subunit (GNB3) C825T (rs5443) single nucleotide polymorphism (SNP) has been implicated as a risk factor for essential hypertension in the general population. The effects of this SNP may be more prominent in subjects with endothelial dysfunction (ED). Rheumatoid arthritis (RA) is associated with ED and has a high prevalence of hypertension. Thus far, this SNP has not been studied in RA patients. We genotyped 383 RA patients and 432 controls. GNB3 C825T was identified using real-time polymerase chain reaction (PCR) and melting curve analysis. There were no differences in the frequencies of the GNB3 C825T genotype and alleles between RA and controls. Within RA patients, prevalence of hypertension did not differ across genotypes. The TT versus CC+CT contrast yielded an adjusted odds ratio (OR) of 0.92 (95% CI: 0.49 to 1.76, p = 0.813), the contrast of TT+CT versus CC an adjusted OR of 2.17 (95% CI: 0.885 to 5.30, p = 0.091), whereas that of the T allele versus C allele an adjusted OR of 1.11 (95% CI: 0.76 to 1.61, p = 0.604). Systolic and diastolic blood pressure levels were not significantly different across the three genotypic groups. No significant interaction was observed between GNB3 825C/T polymorphism and serum endothelin levels. Data from the present study suggest that the T825 variant of the G protein beta 3 subunit gene is unlikely to constitute major susceptibility loci for essential hypertension in Caucasian RA patients. Further larger studies are required to confirm our findings and assess the interaction of rs5443 with environmental factors.

Analysis of correlations between selected endothelial cell activation markers, disease activity, and nailfold capillaroscopy microvascular changes in systemic lupus erythematosus patients

The aim of the study was to evaluate the correlation between selected serum endothelial cell activation markers such as vascular endothelial growth factor (VEGF), endothelin-1 (ET-1), soluble thrombomodulin (sTM), soluble E-selectin (sE-selectin), disease activity, and microvascular changes determined by nailfold capillaroscopy in patients with systemic lupus erythematosus (SLE). Serum levels of VEGF, ET-1, sTM, and sE-selectin were determined by an enzyme-linked immunosorbent assay in 80 SLE patients. The disease activity was measured with Systemic Lupus Erythematosus Disease Activity Index score. Nailfold capillaroscopy was performed in all patients. Positive correlation was found between VEGF and both ET-1 (r = 0.294, p < 0.01) and sE-selectin (r = 0.274, p < 0.05) serum levels as well as between sTM and ET-1 (r = 0.273, p < 0.05) serum concentrations. We noticed also positive correlation between VEGF (r = 0.224, p < 0.05) and ET-1 (r = 0.471, p < 0.001) serum levels and disease activity, and also between VEGF serum concentration and grade of morphological changes observed by nailfold capillaroscopy (r = 0.458, p < 0.001). There was also positive correlation between capillaroscopic score and disease activity (r = 0.339, p < 0.01). Our data suggest that correlation between VEGF and both ET-1 and E-selectin serum levels as well as between sTM and ET-1 serum concentrations may reflect their participation in the pathogenesis of SLE. VEGF seems to reflect changes in microcirculation in the course of SLE, visualised by nailfold capillaroscopy. The relationship between changes in nailfold capillaroscopy, endothelial cell activation markers, and the clinical activity of SLE points to an important role of microvascular abnormalities in the clinical manifestation of the disease.

Polymorphisms of the endothelin-1 gene associate with hypertension in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) associates with excess cardiovascular (CV) morbidity and mortality. Hypertension, a highly prevalent entity in RA, has been associated with the endothelin-1 (ET-1) gene locus (EDN1) in some groups, such as Afro-Caribbean, the obese, and in low-renin states, but not in the general population as a whole. High levels of plasma ET-1 have been observed in RA. This study evaluated the potential association of EDN1 gene locus and serum ET-1 levels with hypertension in patients with RA. Genomic DNA and serum samples were collected from 397 well-characterized RA patients; DNA was also available from 401 local general population controls without RA. To explore the overall relevance of EDN1, two suitable single-nucleotide polymorphisms (SNPs), rs1800541 and rs5370, were selected and haplotype analysis was performed. Both SNPs were identified using real-time polymerase chain reaction (PCR) and melting curve analysis. Genetic analysis was related to hypertension as dichotomous trait and to blood pressure indices as continuous variables. Serum endothelin levels were also assessed in the RA patients. No genotype or haplotype differences were observed between RA and control subjects. Within RA, logistic regression analysis of each SNP separately revealed a threefold increase in the adjusted odds of being hypertensive of rs5370 TT homozygotes compared to GG homozygotes (OR = 2.89, 95%CI: 1.02 to 8.19). After adjustment for multiple potential confounders, haplotype analysis revealed an additive effect of the rs1800541-rs5370 T-T haplotype on hypertension (OR = 2.96, 95%CI: 1.28 to 6.86; p = .011), systolic blood pressure (SBP) (beta = 6.75 +/- 2.57 mm Hg; p = .009), and pulse pressure (PP) (beta = 4.37 +/- 2.12 mm Hg; p = .040). There was an increased prevalence of raised ET-1 levels amongst hypertensive RA patients, whereas a similar trend was observed for T-T haplotype carriers. RA patients who carry the rs1800541-rs5370 T-T EDN1 haplotype appear more likely to be hypertensive with an increased SBP and PP. These findings, if replicated in future studies, could be used as a screening tool for RA patients at increased hypertension, and thus cardiovascular, risk.

The role of ET(A) and ET(B) receptor antagonists in acute and allergic inflammation in mice

In this study, we investigated the effects of the selective ET(A) (BQ-123) and ET(B) (BQ-788) receptor antagonists for endothelin-1 (ET-1) against several flogistic agent-induced paw edema formation and ovalbumin-induced allergic lung inflammation in mice. The intraplantar injection of BQ-123, but not BQ-788, significantly inhibited carrageenan-, PAF-, ET-1- and bradykinin-induced paw edema formation. The obtained inhibitions (1h after the inflammatory stimulus) were 79+/-5%, 55+/-4%, 55+/-6% and 74+/-4%, respectively. In carrageenan-induced paw edema, the mean ID(50) value for BQ-123 was 0.77 (0.27-2.23)nmol/paw. The neutrophil influx induced by carrageenan or PAF was reduced by BQ-123, with inhibitions of 55+/-2% and 72+/-4%, respectively. BQ-123 also inhibited the indirect macrophage influx induced by carrageenan (55+/-6%). However, BQ-788 failed to block the cell influx caused by either of these flogistic agents. When assessed in the bronchoalveolar lavage fluid in a murine model of asthma, both BQ-123 and BQ-788 significantly inhibited ovalbumin-induced eosinophil recruitment (78+/-6% and 71+/-8%), respectively. Neither neutrophil nor mononuclear cell counts were significantly affected by these drugs. Our findings indicate that ET(A), but not ET(B), selective ET-1 antagonists are capable of preventing the acute inflammatory responses induced by carrageenan, PAF, BK and ET-1. However, both ET(A) and ET(B) receptor antagonists were found to be effective in inhibiting the allergic response in a murine model of asthma.

Endothelins modulate inflammatory reaction in zymosan-induced arthritis: participation of LTB4, TNF-alpha, and CXCL-1

Endothelins (ETs) are involved in inflammatory events, including pain, fever, edema, and cell migration. ET-1 levels are increased in plasma and synovial membrane of rheumatoid arthritis (RA) patients, but the evidence that ETs participate in RA physiopathology is limited. The present study investigated the involvement of ETs in neutrophil accumulation and edema formation in the murine model of zymosan-induced arthritis. Intra-articular (i.a.) administration of selective ET(A) or ET(B) receptor antagonists (BQ-123 and BQ-788, respectively; 15 pmol/cavity) prior to i.a. zymosan injection (500 microg/cavity) markedly reduced knee-joint edema formation and neutrophil influx to the synovial cavity 6 h and 24 h after stimulation. Histological analysis showed that ET(A) or ET(B) receptor blockade suppressed zymosan-induced neutrophil accumulation in articular tissue at 6 h. Likewise, dual blockade of ET(A)/ET(B) with bosentan (10 mg/kg, i.v.) also reduced edema formation and neutrophil counts 6 h after zymosan stimulation. Pretreatment with BQ-123 or BQ-788 (i.a.; 15 pmol/cavity) also decreased zymosan-induced TNF-alpha production within 6 h, keratinocyte-derived chemokine/CXCL1 production within 24 h, and leukotriene B(4) at both time-points. Consistent with the demonstration that ET receptor antagonists inhibit zymosan-induced inflammation, i.a. injection of ET-1 (1-30 pmol/cavity) or sarafotoxin S6c (0.1-30 pmol/cavity) also triggered edema formation and neutrophil accumulation within 6 h. Moreover, knee-joint synovial tissue expressed ET(A) and ET(B) receptors. These findings suggest that endogenous ETs contribute to knee-joint inflammation, acting through ET(A) and ET(B) receptors and modulating edema formation, neutrophil recruitment, and production of inflammatory mediators.

Trauma, PTSD, and physical health: an epidemiological study of Australian Vietnam veterans

OBJECTIVE

This study aimed to examine the relative contributions to physical health of combat trauma exposure and posttraumatic stress disorder (PTSD), which have both been implicated separately in poorer physical health but whose unconfounded effects have not been teased out.

METHODS

Data from an epidemiological study of Australian Vietnam veterans, which used personal interviews and standardized physical and psychiatric health assessments, provided the means to assess the independent and joint effects of psychological trauma exposure and PTSD on a wide range of self-reported measures of physical health. Trauma exposure was measured by published scales of combat exposure and peritraumatic dissociation. Logistic regression modeling was used to assess the relative importance of trauma exposure and PTSD to health while controlling for a set of potential confounders including standardized psychiatric diagnoses.

RESULTS

Greater health service usage and more recent health actions were associated more strongly with PTSD, which was also associated with a range of illness conditions coded by the World Health Organization International Classification of Diseases, 9th Edition (asthma, eczema, arthritis, back and other musculoskeletal disorders, and hypertension) both before and after controlling for potential confounders. In contrast, combat exposure and peritraumatic dissociation were more weakly associated with a limited number of unconfounded physical health outcomes.

CONCLUSIONS

This study provided evidence that PTSD, rather than combat exposure and peritraumatic dissociation, is associated with a pattern of physical health outcomes that is consistent with altered inflammatory responsiveness.

Angiogenesis as a therapeutic target in arthritis: learning the lessons of the colorectal cancer experience

The idea of a therapeutic modality aimed at 'starving' a tissue of blood vessels, and consequentially of oxygen and nutrients, was born from the concept that blood vessel formation (angiogenesis) is central to the progression and maintenance of diseases which involve tissue expansion/invasion. In the first instance, solid malignancies were the target for anti-angiogenic treatments, with colorectal cancer being the first disease for which an angiogenesis inhibitor--anti-vascular endothelial growth factor antibody bevacizumab--was approved in 2004. Our understanding of the pathogenesis of rheumatoid arthritis (RA) has lead to many parallels being drawn between this chronic inflammatory disease and solid tumours, in that both involve tissue expansion, invasion, expression of cytokines and growth factors and areas of hypoxia/hypoperfusion. As a result, angiogenesis blockade has been touted as a possible treatment for RA. The lessons learnt during the progression of eventually successful therapies such as bevacizumab should undoubtedly guide us in the future development of comparable treatments for RA.

Gingival Crevicular Fluid VEGF Levels in Periodontal Health and Disease

BACKGROUND

Vascular endothelial growth factor (VEGF), a glycoprotein, has attracted attention as a potential inducer of angiogenesis. It is detectable in periodontal tissues within endothelial cells, plasma cells, and macrophages and in junctional, sulcular, and gingival epithelium. In periodontitis patients, the volume of gingival crevicular fluid (GCF) and the total amount of VEGF collected from diseased sites were greater than from clinically healthy sites. The aim of the present study was to investigate the role of VEGF in periodontal disease progression and to investigate the effect of periodontal therapy on VEGF concentrations in GCF.

METHODS

Forty-five subjects were divided into three groups based on gingival index, clinical attachment loss, and radiographic evidence of alveolar bone loss: healthy (group 1), gingivitis (group 2), and chronic periodontitis (group 3). A fourth group consisted of subjects from group 3, 8 weeks after treatment (scaling and root planing). GCF samples collected from each patient were quantified for VEGF levels using enzyme-linked immunosorbent assay. Further, the correlation between VEGF levels in situ and the clinical parameters was analyzed in all groups and was analyzed before and after treatment in the periodontitis group.

RESULTS

The highest mean VEGF concentration (99.375 pg/ml) was observed in group 3, and the lowest was observed in group 1 (42.025 pg/ml). Its mean level in group 3 decreased to 54.60 pg/ml after treatment (group 4). Further, GCF VEGF levels showed a positive correlation with all of the clinical parameters.

CONCLUSIONS

VEGF levels in GCF increased from health to periodontitis, and periodontal treatment resulted in a reduction in their concentrations. These data indicated that VEGF plays a key role in periodontal disease progression and can be considered a biomarker of periodontal disease progression.

Increased endothelin-1 and diminished nitric oxide levels in blister fluids of patients with intermediate cold type complex regional pain syndrome type 1

Background

In complex regional pain syndrome type 1 (CRPS1) pro-inflammatory mediators and vascular changes play an important role in the sustained development and outcome of the disease. The aim of this study was to determine the involvement of vasoactive substances endothelin-1 (ET-1) and nitric oxide (NO) during early chronic CRPS1.

Methods

Included were 29 patients with CRPS 1 who were diagnosed during the acute stage of their disease and observed during follow-up visits. Disease activity and impairment were determined and artificial suction blisters were made on the CRPS1 and the contralateral extremities for measurements of IL-6, TNF-α, ET-1 and nitrate/nitrite (NOx).

Results

The levels of IL-6, TNF-α and ET-1 in blister fluid in the CRPS1 extremity versus the contralateral extremity were significantly increased and correlated with each other, whereas NOx levels were decreased.

Conclusion

The NOx/ET-1 ratio appears to be disturbed in the intermediate stage of CRPS, resulting in vasoconstriction and consequently in a diminished tissue blood distribution.