A2A adenosine receptor agonist reduced MMP8 expression in healthy M2-like macrophages but not in macrophages from ankylosing spondylitis patients.

BACKGROUND: Ankylosing spondylitis (AS) is an inflammatory autoimmune disease that mostly affects different joints of the body. Macrophages are the predominant cells that mediate disease progression by secreting several pro-inflammatory mediators. Different receptors are involved in macrophages' function including the adenosine receptors (AR). Our main objective in this study was to assess the effect of applying A2A adenosine receptor agonist (CGS-21,680) on the gene expression of inflammatory mediators including bone morphogenetic proteins (BMP)-2, 4 and matrix metalloproteinases (MMP)-3, 8, 9, and 13 on the macrophages from AS patients compared to healthy macrophages. METHODS: Monocytes were isolated from the whole blood of 28 individuals (AS patients and healthy controls in a 1:1 ratio). Macrophages were differentiated using macrophage colony-stimulating factor (M-CSF), and flow cytometry was performed to confirm surface markers. CGS-21,680 was used to treat cells that had been differentiated. Using SYBR green real-time PCR, relative gene expression was determined. RESULTS: Activating A2AAR diminished MMP8 expression in healthy macrophages while it cannot reduce MMP8 expression in patients' macrophages. The effect of A2AAR activation on the expression of BMP2 and MMP9 reached statistical significance neither in healthy macrophages nor in the patients' group. We also discovered a significant positive connection between MMP8 expression and patient scores on the Bath ankylosing spondylitis functional index (BASFI). CONCLUSION: Due to the disability of A2AAR activation in the reduction of MMP8 expression in patients' macrophages and the correlation of MMP8 expression with BASFI index in patients, these results represent defects and dysregulations in the related signaling pathway in patients' macrophages.

Genome-wide association study in Turkish and Iranian populations identify rare familial Mediterranean fever gene (MEFV) polymorphisms associated with ankylosing spondylitis.

Ankylosing spondylitis (AS) is a highly heritable immune-mediated arthritis common in Turkish and Iranian populations. Familial Mediterranean Fever (FMF) is an autosomal recessive autoinflammatory disease most common in people of Mediterranean origin. MEFV, an FMF-associated gene, is also a candidate gene for AS. We aimed to identify AS susceptibility loci and also examine the association between MEFV and AS in Turkish and Iranian cohorts. We performed genome-wide association studies in 1001 Turkish AS patients and 1011 Turkish controls, and 479 Iranian AS patients and 830 Iranian controls. Serum IL-1ß, IL-17 and IL-23 cytokine levels were quantified in Turkish samples. An association of major effect was observed with a novel rare coding variant in MEFV in the Turkish cohort (rs61752717, M694V, OR = 5.3, P = 7.63×10(-12)), Iranian cohort (OR = 2.9, P = 0.042), and combined dataset (OR = 5.1, P = 1.65×10(-13)). 99.6% of Turkish AS cases, and 96% of those carrying MEFV rs61752717 variants, did not have FMF. In Turkish subjects, the association of rs61752717 was particularly strong in HLA-B27-negative cases (OR = 7.8, P = 8.93×10(-15)), but also positive in HLA-B27-positive cases (OR = 4.3, P = 7.69×10(-8)). Serum IL-1ß, IL-17 and IL-23 levels were higher in AS cases than controls. Among AS cases, serum IL-1ß and IL-23 levels were increased in MEFV 694V carriers compared with non-carriers. Our data suggest that FMF and AS have overlapping aetiopathogenic mechanisms. Functionally important MEFV mutations, such as M694V, lead to dysregulated inflammasome function and excessive IL-1ß function. As IL-1 inhibition is effective in FMF, AS cases carrying FMF-associated MEFV variants may benefit from such therapy.

Activation of adenosine A2A receptor induced interleukin-23 mRNA expression in macrophages of ankylosing spondylitis patients.

BACKGROUND: Ankylosing spondylitis (AS) is an auto-inflammatory debilitating disorder with a complex pathogenesis. The adenosinergic pathway is an immunologic regulating pathway with a potential role in AS pathophysiology. In the present study, we have aimed to investigate the influence of A2A adenosine receptor (A2AAR) activation on tumor necrosis factor-α (TNF-α) and interleukin-23 (IL-23) expression and secretion by monocyte-generated macrophages of AS patients. METHODS: Whole-blood separated monocytes were extracted from 14 AS patients and 14 healthy controls. Macrophages were differentiated by macrophage colony-stimulating factor (M-CSF), and surface markers were confirmed by flow cytometer. Cells were treated with CGS-21680 as a known agonist of A2AAR. Analysis of ADORA2A, TNFA, and IL23A gene expression was performed by SYBR green real-time PCR. The concentration of secreted cytokines was also measured by ELISA kits. RESULTS: Based on our analysis, CGS-21680 significantly decreased TNF-α secretion by monocyte-derived macrophages of AS patients. Moreover, A2AAR agonist increased the IL23A mRNA expression level in monocyte-derived macrophages of AS patients considerably. Whereas, CGS-21680 did not have any influence on macrophages of healthy individuals. CONCLUSION: According to our results, it appears that A2AAR activation can increase IL-23 secretion by monocyte-derived macrophages of AS patients. Although the TNF-α reducing effect of A2AAR agonists can be a potential target in AS treatment, robust increasing of IL-23 should be considered as the undesirable effect of these agents.

Association study of copy number variation in BMP8A gene with the risk of ankylosing spondylitis in Iranian population.

BACKGROUND: Copy number variation (CNV) of DNA segments has been considered as an important component of genetic variation, affecting the quality and quantity of gene expression. Bone morphogenic protein 8A (BMP8A) has been reported to function in bone formation. With respect to the bone and joint complications in ankylosing spondylitis (AS), this investigation aimed to study the role of BMP8A gene CNV in impressing the gene expression as well as the disease risk. METHODS: A total of 900 individuals, including 450 patients with AS and 450 healthy controls were enrolled. The copy numbers of BMP8A gene were detected by TaqMan real-time polymerase chain reaction (PCR) method. BMP8A messenger RNA (mRNA) transcript level in peripheral blood mononuclear cells (PBMCs) was also measured by SYBR Green real-time gene expression PCR method. RESULTS: No significant association of BMP8A copy number was detected with the risk of AS. BMP8A mRNA expression level was significantly downregulated in patients compared with controls. mRNA expression level of BMP8A in both AS patients with and without syndesmophyte was significantly lower than the healthy control group. There was no correlation between the mRNA expression level of BMP8A and both demographic and clinical data of the patients. CONCLUSIONS: Although BMP8A gene expression was downregulated in patients with AS, its copy number could not affect the transcript level of BMP8A gene in PBMCs and was not associated with susceptibility to AS in Iranian population. BMP8a may take into account as an indicator of bone formation process in AS, but it seems that mechanisms other than CNV may regulate this protein.

Increased inflammatory responsiveness of peripheral blood mononuclear cells (PBMCs) to in vitro NOD2 ligand stimulation in patients with ankylosing spondylitis.

Background: Ankylosing spondylitis (AS) is a common debilitating rheumatic disease in which the innate immune components especially the Interleukin (IL)-23/IL-17 axis related genes play important role in its pathogenesis. Nucleotide binding oligomerization domain-containing protein (NOD)2, as an innate receptor, is critical for IL-23 production in cells. Therefore, we aimed to stimulate NOD2 signaling and study its effects on cytokine production in peripheral blood mononuclear cells (PBMC) of these patients. Methods: PBMCs from 18 patients with active AS and 18 healthy individuals were separated by Ficoll-Hypaque density gradient centrifugation and cultured in the presence of muramyl dipeptide (MDP), as NOD2 ligand. Quantitative expression analysis of NOD1, NOD2, RIPK2, SLC15A4, NLRP1, NLRP3, IL23A, IL17A, IL1B, and TNFA genes was performed using Real-time polymerase chain reaction (PCR). Finally, protein changes of IL23A and IL17A expression were validated using enzyme linked immunosorbent assay (ELISA). Results: Apart from NOD1 that tend to be downregulated in the controls, all the selected genes showed overexpression in response to MDP in cells from the studied groups. Except RIPK2, all the genes had higher expression changes upon MDP stimulation in the AS population. Overexpression of IL23A and IL17A were confirmed at protein levels using ELISA. The strong positive correlation between NLRP3 and NOD2 was decreased after stimulation but new correlations between NLRP3 and IL1B, RIPK2 and SLC15A4 were observed after treatment. Conclusions: This study indicated that AS PBMCs were hyper-responsive to MDP stimulation. This observation implies an important role of NOD2 in the pathogenesis of inflammatory diseases including AS.

Targeting of circulating Th17 cells by ß-D-mannuronic acid (M2000) as a novel medication in patients with rheumatoid arthritis.

OBJECTIVE: This study aimed at investigating the inhibitory effect of ß-D-mannuronic acid (M2000) on the Th17 circulating levels and IL-17 a related cytokine in rheumatoid arthritis (RA) patients. METHODS: The study included 27 patients with RA who had failed response to treatment. All patients were treated orally by M2000 at a dose of 500 mg twice daily for 12 weeks (Clinical trial identifier: IRCT2014011213739N2). The patients based on anti-tumor necrosis factor alpha (TNFα) blocker treatment were classified into two groups (conventional group and etanercept group). They were then allowed to continue their treatment excluding non-steroidal anti-inflammatory drugs (NSAIDs). The frequency of circulating Th17 cells and IL-17 serum level were determined before and 12 weeks after M2000 therapy and were compared to the healthy controls by using flow cytometry analysis and ELISA method, respectively. RESULTS: At baseline, higher circulating Th17 and IL-17 serum levels were significantly observed in both groups of RA patients than in the healthy controls (all P < 0.001). The frequency of Th17 cells significantly decreased in the conventional group as well as in the etanercept group after M2000 therapy but the level of reduction was higher in the conventional group compared to the etanercept group (P < 0.03 and P < 0.04, respectively). The IL-17 serum level significantly decreased in both groups after M2000 therapy (P < 0.01 and P < 0.02, respectively). Furthermore, the frequency of Th17 cells was positively correlated with Disease Activity Score (DAS28) (r = 0.34, P = 0.02). CONCLUSION: M2000 shows the inhibitory effect on the frequency of circulating Th17 cells as well as in the production of IL-17 in RA patients.

A phase I/II randomized, controlled, clinical trial for assessment of the efficacy and safety of ß-D-mannuronic acid in rheumatoid arthritis patients.

BACKGROUND: Following the potent efficacy of ß-D-mannuronic acid (M2000) in phase I/II trial in ankylosing spondylitis patients, the present clinical trial was conducted to evaluate the efficacy, safety, and tolerability of this novel drug in rheumatoid arthritis (RA) patients who had inadequate response to conventional therapy. METHOD: The study was a 12-week randomized, controlled, phase I/II clinical trial with two treatment arms: M2000 and conventional treatment. Patients who had RA according to the modified American College of Rheumatology (ACR) criteria, with active disease at baseline also inadequate response to conventional therapy, were enrolled in this study. M2000 was administrated at a dose of two capsules (500 mg) per day orally during a period of 12 weeks. The primary endpoint was the proportion of patients fulfilling the ACR 20% improvement criteria after 12 weeks of M2000 therapy. Moreover, the patients were also followed up for safety. RESULTS: There were no statistically significant differences between treatment and conventional groups at baseline characteristics. The ACR20 response rate was significantly higher among M2000-treated patients than conventional-treated control, so that 74% of patients in treatment group showed an ACR20 response after 12 weeks of M2000 therapy (74 versus 16%; P = 0.011). 10% of M2000-treated patients and 57.1% of conventional-treated patient's adverse events occurred during this study. CONCLUSION: Treatment with M2000 in combination with conventional therapy showed a significantly superior efficacy along with a high safety profile compared to conventional-treated patients. Thereby, M2000 might be suggested as a suitable option in the treatment of RA.

The effects of ß-D-mannuronic acid (M2000), as a novel NSAID, on COX1 and COX2 activities and gene expression in ankylosing spondylitis patients and the murine monocyte/macrophage, J774 cell line.

Ankylosing spondylitis (AS) is a debilitating chronic inflammatory disease with genetic predisposition, which is characterized by the involvement of spine and sacroiliac joints. Due to the relatively unsuccessful treatments, we designed ß-D-mannuronic (M2000) with the beneficial effects in various experimental models as a novel non-steroidal anti-inflammatory drug (NSAID). The aims of our present study were: first, to compare the therapeutic effects of M2000, as a novel designed NSAID, with naproxen and placebo in Iranian patients with AS during 12 weeks; second, to evaluate the effect of M2000 on gene expression of cyclooxygenase enzyme (COX-1/COX-2), a key enzyme in the initiation of inflammatory pathways in AS patients; and third, to assess the activity of COX-1 and COX-2 enzymes in the presence/absence of M2000 at the different doses in the murine macrophage, J774 cell line. This was a sub-study of phase II, randomized, placebo-controlled trial with three treatment arms: M2000, naproxen, and placebo. The outcome measures were the mean changes from baseline to week 12. The gene expression was assessed by real-time PCR. The COX-1 and COX-2 activities were evaluated by ELISA in J774 cell line induced by LPS and arachidonic acid (AA). Our findings demonstrated that M2000 had beneficial therapeutic effects on pain, stiffness, and inflammation, whereas no adverse effects were observed following the use of M2000 after 12 weeks. The analysis of gene expression showed that M2000 could effectively reduce the expression levels of COX-1 and COX-2 in comparison with untreated patients. In addition, the enzymatic activities in the presence of M2000 were significantly less than LPS- and AA-treated groups. Our results indicate that M2000, as a novel designed NSAID with immunosuppressive properties, can be considered as one of the therapeutic options for the treatment of inflammatory diseases without adverse events. Clinical trial identifier IRCT2013062213739N1/ http://www.IRCT.ir .

Ankylosing spondylitis M-CSF-derived macrophages are undergoing unfolded protein response (UPR) and express higher levels of interleukin-23.

OBJECTIVE: Interleukin (IL)-23/IL-17 pathway involves in the pathogenesis of ankylosing spondylitis (AS). The exact mechanism implicated in overexpression of IL-23 and activation of the IL-23/IL-17 axis is not clear. The aim of the study was to clarify whether macrophages of AS patients undergo unfolded protein response (UPR) and secret increased IL-23. METHODS: Peripheral blood monocyte isolated from 10 HLA-B27+ patients and five HLA-B27+ normal subjects were differentiated to macrophages by macrophage-colony stimulating factor (M-CSF) for seven days. Flow cytometry was used to detect monocyte purity and expression of macrophage markers. Analysis of mRNA expression for HLA-B and B27, UPR-associated proteins (BiP, CHOP, MDG1, and XBP1) and IL-23 was performed by RT-qPCR. RESULTS: RT-qPCR data showed a significant overexpression of HLA-B27, UPR genes (BiP, CHOP, and XBP1), and IL-23 in M-CSF-derived macrophages from AS patients compared to healthy controls. Increased expression of MDG1 was not significant. CONCLUSIONS: Our data suggest that UPR activation occurs in M-CSF-derived macrophages of AS patients and is accompanied by overexpression of HLA-B27. UPR appears to be associated with overproduction of IL-23 in AS macrophages.

Validity and reliability of the Persian version of Behçet's disease quality-of-life (BD-QoL) questionnaire: a cross-cultural adaptation.

The Leeds Behçet's disease quality-of-life (BD-QoL) questionnaire is a specific and valid measure which is applied in English-speaking patients. We conducted Persian adaptation of BD-QoL questionnaire. Between June and December 2012, 220 Iranian patients fulfilling International Study Group criteria for the diagnosis of BD attending the rheumatology clinics at Tehran University of Medical Sciences were enrolled. Bilingual translators undertook the forward translation and cross-cultural adaptation of the BD-QoL questionnaire. Back-translation was conducted, and this version was sent to the designer of the questionnaire and revised accordingly. SF-36 health survey, Iranian Behçet's disease dynamic activity measure (IBDDAM), and Behçet's Disease Current Activity Form (BDCAF) were other administered measures. The Varimax rotation method with Kaiser normalization defined 5 factors with eigenvalues greater than 1.0. Studied cases were comprised of 118 males (53.6 %) and 102 females (46.4 %). Mean age of the patients was 38.3 ± 11.3 years (range 16-73). The mean BD-QoL score was 10.3 ± 8.8. Test-retest reliability was high, and two time points were significantly correlated (Spearman's correlation coefficient of 0.75-0.84). Cronbach's α coefficient of 0.949 demonstrated the excellent internal consistency. These factors cumulatively explained 58.74 % of total variance. The ratio of first to second eigenvalue was 7.08, which underlined the undimensionality. The results revealed adapted BD-QoL scores had significant correlation with IBDDAM (correlation coefficient = 0.19, P value = 0.005) and BDCAF (correlation coefficient = 0.21, P value = 0.002). Conversely, no significant correlation between BD-QoL and SF-36 results was detected (P value = 0.078). The Persian version of BD-QoL was shown to be unidimensional, highly reliable, and adequate construct validity.