The phagocyte oxidative metabolism function in ankylosing spondylitis

Predicting the potential ankylosing spondylitis-related genes utilizing bioinformatics approaches

Given that ankylosing spondylitis (AS) occurs in approximately 5 out of 1,000 adults of European descent and the unclear pathogenesis, the aim of the research was to further predict the molecular mechanism of this disease. The Affymetrix chip data GSE25101 were available from Gene Expression Omnibus database. First of all, differentially expressed genes (DEGs) were identified by Limma package in R. Moreover, DAVID was used to perform gene set enrichment analysis of DEGs. In addition, miRanda, miRDB, miRWalk, RNA22 and TargetScan were applied to predict microRNA-target associations. Meanwhile, STRING 9.0 was utilized to collect protein-protein interactions (PPIs) with confidence score >0.4. Then, the PPI networks for up- and down-regulated genes were constructed, and the clustering analysis was undergone using ClusterONE. Finally, protein-domain enrichment analysis of modules was conducted using DAVID. Total 145 DEGs were identified, including 103 up-regulated and 42 down-regulated genes. These DEGs were significantly enriched in phosphorylation (p = 1.21E-05) and positive regulation of gene expression (p = 1.25E-03). Furthermore, one module was screened out from the up-regulated network, which contained 39 nodes and 205 edges. Moreover, the nodes in the module were significantly enriched in ribosomal protein (RPL17, ribosomal protein L17 and MRPL22, mitochondrial ribosomal protein L22) and proteasome (PSMA6, proteasome subunit, alpha type 6, PSMA4)-related domains. Our findings that might explore the potential pathogenesis of AS and RPL17, MRPL22, PSMA6 and PSMA4 have the potential to be the biomarkers for the disease.

Association of cytokine and matrix metalloproteinase profiles with disease activity and function in ankylosing spondylitis

Introduction

The pathology of ankylosing spondylitis (AS) suggests that certain cytokines and matrix metalloproteinases (MMPs) might provide useful markers of disease activity. Serum levels of some cytokines and MMPs have been found to be elevated in active disease, but there is a general lack of information about biomarker profiles in AS and how these are related to disease activity and function. The purpose of this study was to investigate whether clinical measures of disease activity and function in AS are associated with particular profiles of circulating cytokines and MMPs.

Methods

Measurement of 30 cytokines, five MMPs and four tissue inhibitors of metalloproteinases was carried out using Luminex^® technology on a well-characterised population of AS patients (n = 157). The relationship between biomarker levels and measures of disease activity (Bath ankylosing spondylitis disease activity index (BASDAI)), function (Bath ankylosing spondylitis functional index) and global health (Bath ankylosing spondylitis global health) was investigated. Principal component analysis was used to reduce the large number of biomarkers to a smaller set of independent components, which were investigated for their association with clinical measures. Further analyses were carried out using hierarchical clustering, multiple regression or multivariate logistic regression.

Results

Principal component analysis identified eight clusters consisting of various combinations of cytokines and MMPs. The strongest association with the BASDAI was found with a component consisting of MMP-8, MMP-9, hepatocyte growth factor and CXCL8, and was independent of C-reactive protein levels. This component was also associated with current smoking. Hierarchical clustering revealed two distinct patient clusters that could be separated on the basis of MMP levels. The high MMP cluster was associated with increased C-reactive protein, the BASDAI and the Bath ankylosing spondylitis functional index.

Conclusions

A profile consisting of high levels of MMP-8, MMP-9, hepatocyte growth factor and CXCL8 is associated with increased disease activity in AS. High MMP levels are also associated with smoking and worse function in AS.

Evaluation of serum paraoxonase and arylesterase activities in ankylosing spondylitis patients

OBJECTIVES

The aim of this study was to investigate the activities of serum paraoxonase and arylesterase in patients with ankylosing spondylitis with respect to those of healthy controls, to assess whether these enzyme levels are related to disease activity and functional capacity.

METHODS

The study included 32 patients with ankylosing spondylitis whose diagnoses were made according to the modified New York criteria as well as 25 healthy controls matched for age and sex. The Bath Ankylosing Spondylitis Disease Activity Index and the Bath Ankylosing Spondylitis Functional Index were applied to the ankylosing spondylitis patients. As laboratory parameters, the erythrocyte sedimentation rate and serum C-reactive protein level were measured in patients and control subjects. Paraoxonase and arylesterase enzyme activities were measured using appropriate methods.

RESULTS

No statistically significant differences (p>0.05) were found between the ankylosing spondylitis patients and controls in terms of serum paraoxonase or arylesterase levels. Furthermore, there was no correlation between clinical and laboratory parameters in patients with ankylosing spondylitis.

CONCLUSION

Serum paraoxonase and arylesterase levels in ankylosing spondylitis patients may not differ from those of healthy controls, and there is no significant correlation between antioxidant parameters and the Bath Ankylosing Spondylitis Disease Activity Index or Bath Ankylosing Spondylitis Functional Index scores in ankylosing spondylitis patients. Further research is needed to provide deeper understanding of this disease.

Serum oxidative-antioxidative status in patients with ankylosing spondilitis

Ankylosing spondylitis (AS) is an inflammatory disorder with unknown etiology that mainly affects the axial skeleton as well as the peripheral joints and extra-articular structures. The aim of this study was to evaluate the total antioxidant status (TAS), total oxidative status (TOS) and oxidative stress index (OSI) in patients with ankylosing spondylitis (AS). Fifty AS patients with a mean Bath AS Activity Index (BASDAI) 4.6 (range 4-9.3) and 26 healthy controls were included in the study. Plasma TAS, TOS levels were determined by using novel automated methods. The OSI was calculated. Plasma TOS level and OSI values were significantly higher, and plasma TAS level was lower in patients than in healthy controls (15.8 +/- 4. 9 vs. 4.3 +/- 2.8, 12.8 +/- 3. 9 vs. 9.6 +/- 5.5, 1.2 +/- 0.03 vs. 1.8 +/- 0.2, respectively, P < 0.001 for all). There was no significant correlation between oxidant/antioxidant parameters and disease activity. The results of this study indicated that increased oxidant and decreased antioxidant capacity may be associated with the pathogenesis of AS.

The oxidative metabolism of circulating phagocytes in ankylosing spondylitis: determination by whole blood chemiluminescence

OBJECTIVE

Superoxide anion radicals within the human body are regarded as a major cause of inflammation. However, their role in the pathogenesis of ankylosing spondylitis (AS) has not been well identified. This study aimed at investigating the relation between AS and the oxidative metabolism of phagocytes in whole blood.

METHODS

24 patients with classic AS were examined to determine their clinical status; complete blood count, erythrocyte sedimentation rate (ESR), and C reactive protein (CRP) were determined, and levels of the superoxide anion radicals in the patients with AS and 21 healthy subjects were assessed by the ultraweak chemiluminescence method. Subsequently, the relation between this disease and phagocytes was examined by using N-formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol-12-myristate-13-acetate (PMA) stimulants.

RESULTS

In clinical assessments, patients with AS had abnormally raised serum CRP (>10 mg/l) and ESR (>15 mm/1st h) levels. In contrast with healthy subjects, patients with AS had significantly increased rates of superoxide anion radical production in their whole blood either in the resting state or with either fMLP or PMA stimulation. In addition, chemiluminescence maximum light intensity was significantly higher in patients with AS than in healthy subjects after fMLP or PMA stimulation.

CONCLUSIONS

Our results suggest that the phagocytes of patients with AS are partly activated in the resting state, and are sensitive to fMLP or PMA stimulation. The priming of phagocytes in the bloodstream is likely to be a causative factor in the onset of AS.

Helicobacter pylori, neutrophils, interleukins, and gastric epithelial proliferation

Infection of Helicobacter pylori causes chronic gastritis and plays an important role in the pathogenesis of gastroduodenal ulceration. H. pylori has also been suggested to be involved in the genesis of adenocarcincoma and MALT lymphoma of the stomach. H. pylori infection is associated with increased gastric epithelial proliferation, which can be reversed by a successful eradication of the organism. Although the mechanisms of increased gastric epithelial proliferation is not known, the enhanced epithelial proliferation is important in developing gastric carcinoma. Whether or not H. pylori de nove stimulates gastric epithelial proliferation is controversial, but gastric infection with H. pylori activates a mucosal inflammatory response by consisting of large numbers of polymorphonuclear and mononuclear cells, that also includes expression of various cytokines including interleukin-8. We review the mechanisms of H. pylori in enhanced gastric epithelial cell proliferation and cytokines in patients with H. pylori infection.

A simple, sensitive, non-stimulated photon counting system for detection of superoxide anion in whole blood

A simple, sensitive, non-stimulated assay was developed to measure the superoxide anion concentration in whole blood, using an ultra-sensitive chemiluminescence (CL) analyzer and lucigenin amplification. The assay system can be performed without leukocyte isolation or stimulant administration. The blood CL levels of healthy males (362.8 +/- 337.7 counts /10 sec) were not different from those of females (335 +/- 308.7 counts/10 sec) (p=0.64), whereas the CL levels in whole blood in patients with acute pancreatitis (2522 +/- 2014 counts/10 sec) were significantly higher than those of healthy controls (p<0.001). This assay system may be valuable in the future for quantitative measurement of reactive oxygen species in various disorders.