Metin Ozgen

Serum Adiponectin and Vaspin Levels in Rheumatoid Arthritis

BACKGROUND AND AIMS The risks of insulin resistance and accelerated atherosclerosis are increased in chronic inflammatory diseases including rheumatoid arthritis (RA). Adipo-(cyto)kines are associated with insulin resistance, atherosclerosis and inflammation. This study aimed to determine serum adiponectin and vaspin levels and their associations with the predictors of atherosclerosis in RA and Behcets disease (BD). METHODS The study involved 56 patients with RA, 37 patients with BD, and 29 healthy controls (HC). Serum adiponectin and vaspin levels, homeostasis model assessment for insulin resistance (HOMA-IR) index, and common carotid intima-media thickness (IMT) were determined. RESULTS Serum adiponectin levels in both patient groups and serum vaspin level in only the RA group were higher, whereas serum vaspin level was lower in the active BD subgroup, compared to the HC group. However, adiponectin and vaspin levels were correlated with neither HOMA-IR index nor IMT in the RA group. Adiponectin level was correlated with DAS-28 and IL-6 level in the RA group, and it was higher in the active BD subgroup than in the inactive BD subgroup and the HC group. CONCLUSIONS Adiponectin and vaspin levels are higher in RA but associated with neither HOMA-IR index nor IMT. Adiponectin is related with disease activity remarks in RA and BD. Therefore, it may be suggested that adiponectin may be involved in the regulation of inflammatory responses in inflammatory diseases. Moreover, in contrast to in RA, vaspin level declines in active BD, and these results suggest that different chronic inflammatory diseases exert different influences on either adipokines.

Visfatin levels and intima-media thicknesses in rheumatic diseases.

Chronic inflammatory rheumatic diseases lead to increased prevalence of atherosclerosis. However, this early and accelerated atherosclerosis cannot be explained by traditional cardiovascular risk factors alone. The permanent overexpression of cellular adhesion molecules and pro-inflammatory cytokines in chronic inflammatory conditions may participate in accelerated atherosclerosis. Visfatin, a novel adipocytokine, has a potential insulin-like action and pro-inflammatory effects. Therefore, the aim of the study was to determine serum visfatin level and its association with common carotid intima-media thickness (IMT), which is a predictor of atherosclerosis, in patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and Behçet’s disease (BD). The study involved 29 RA, 26 SLE, 25 SSc, 30 BD patients, and 29 healthy controls (HC). Serum levels of TNF-α, IL-6, and visfatin were analyzed using enzyme-linked immunosorbent assay method and homeostasis model assessment for insulin resistance (HOMA-IR) indexes, and IMTs were determined. Serum visfatin level was higher in the RA group than all the other groups. In addition, visfatin level was higher in the active BD subgroup than the inactive BD subgroup. In the study groups, visfatin levels were not correlated with HOMA-IR indexes and IMTs. Whereas visfatin serum concentration was not associated with insulin resistance and carotid atherosclerosis in selected rheumatic diseases, it was higher in the RA and active BD groups, but not in the SLE and SSc groups. Visfatin levels may be associated with Th1/Th2 balance. Further studies are needed for more precise elucidation of the pro-inflammatory activities of visfatin.

Ghrelin and Obestatin Levels in Rheumatoid Arthritis

Background: Ghrelin is a powerful, endogenous orexigenic peptide. In addition, ghrelin has anti-inflammatory effects, and it has been reported that ghrelin down-regulates pro-inflammatory cytokines, including interleukin (IL)-1β and tumor necrosis factor (TNF)-α. Obestatin appears to decrease food intake and appetite, and its potential role in inflammation is not yet clear. The aims of this study were to assess total and acylated (active) ghrelin and obestatin serum levels and their relations with inflammatory status in rheumatoid arthritis (RA) patients. Design: Fasting blood samples were obtained from 37 patients with RA, 29 patients with Behçet’s disease (BD) and 28 healthy controls (HC). Total ghrelin and obestatin levels were measured by radioimmunoassay and acylated ghrelin was quantified by enzyme-linked immunosorbent assay. Results: Patients with RA had lower total ghrelin, but higher obestatin levels than patients with BD (p < 0.05 for both), but when compared with HC group differences were not significant. There was no difference across groups in terms of acylated ghrelin. Total ghrelin level was not correlated with any study parameters in the all groups. Obestatin level correlated with erythrocyte sedimentation rate and DAS-28 in the RA group, the level of IL-6 in the BD group, and with the level of TNF-α in the HC group (r = 0.400, p < 0.05; r = 0.412, p < 0.05, r = 0.543, p < 0.01 and r = 0.528, p < 0.05, respectively). Conclusions: Our results did not show a significant correlation between circulating ghrelin and clinical or laboratory markers of disease activity in RA. Surprisingly, obestatin correlated with some inflammatory markers. So, obestatin seems to be more valuable than ghrelin in the pathogenesis of RA.

Prevalence and significance of MEFV gene mutations in a cohort of patients with rheumatoid arthritis

OBJECTIVES Pyrin/marenostrin, an inhibitory regulator of inflammation, is encoded by MEditerranean FeVer (MEFV) gene. Mutations of this gene are the cause of familial Mediterranean fever (FMF). A connection between MEFV gene mutations and rheumatic diseases has been suggested. The aim of this study was to explore the frequency and clinical significance of MEFV gene mutations in a cohort of Turkish patients with rheumatoid arthritis (RA). METHODS The study included 103 patients with RA and 103 age-, sex- and origin-matched healthy controls (HC). In all participants, genomic DNA was isolated and genotyped using amplification refractory mutation system or restriction fragment length polymorphism for the eight MEFV gene mutations (E148Q, M694V, M694I, M680I, V726A, A744S, R761H, and P369S). In the RA group, disease activity was determined using the disease activity score-28 (DAS-28), and radiological damage was evaluated by the modified Larsen scoring method. RESULTS Carrier rates of MEFV gene mutations were 26/103 (25.2%) and 24/103 (23.3%) in the RA and HC groups, respectively (p>0.05, OR: 0.9, 95% CI: 0.48-1.71). In the RA group, while deformed joint count was significantly higher in the mutation carrier group than those of the non-carrier group (p<0.05), the level of C-reactive protein, DAS-28 and modified-Larsen scores were slightly but not significantly higher in the carrier group. CONCLUSION The results of this study suggest that MEFV gene mutations appear to be an aggravating factor for the severity of RA, and consequently, patients with RA might be screened for MEFV gene mutations in countries where FMF is frequent. Whether the searching of MEFV gene mutations in RA patients is cost-effective deserves further investigations.

Association Between Thr21Met and Ser89Asn Polymorphisms of the Urotensin II Gene and Systemic Sclerosis

Objective. Systemic sclerosis (SSc) is an autoimmune chronic fibrotic disorder. Urotensin II (U-II) is predominantly a vasoactive peptide with fibrotic and prothrombotic features. Like endothelin-1 (ET-1), U-II could play an important role in SSc pathogenesis. We evaluated the possible role of the U-II gene polymorphisms (Thr21Met and Ser89Asn) in the genetic susceptibility to SSc in a Turkish population. Methods. A total of 189 patients with SSc and 205 healthy controls were enrolled in our study. We analyzed the genotype and allele frequencies of the U-II (UTS2) gene polymorphisms Thr21Met and Ser89Asn in patients with SSc and in controls. Results. We found that the Thr21Met polymorphism of the UTS2 gene was markedly associated with the risk of developing SSc (p < 0.0001), but there was no relationship between the Ser89Asn polymorphism and SSc (p > 0.05). Two haplotypes (MS and TS) were markedly associated with SSc (p < 0.05). There were significant associations between the genotype and allele frequencies of UTS2 gene Thr21Met polymorphism and cases with diffuse or limited SSc, systemic or lung involvement, finger flexion deformity, pitting scars at the fingertips, positive anticentromere, or positive antitopoisomerase 1 antibody groups. Conclusion. Our study shows the association between Thr21Met, but not Ser89Asn, in the UTS2 gene and SSc. The results strongly suggest that this single-nucleotide polymorphism may be an important risk factor in the development of SSc, and a powerful indicator of severe skin and lung involvement in patients with SSc.

Serum salusin-alpha level in rheumatoid arthritis

Rheumatoid arthritis (RA), a chronic inflammatory disease, leads to early and accelerated atherosclerosis; however, its pathogenesis is not yet fully documented. Salusin-α and β are novel bioactive peptides. Salusin-α suppresses macrophage foam cell formation, while salusin-β stimulates. Moreover, decreased serum salusin-α level has been reported previously in patients with coronary artery disease. The aims of the study were to assess serum salusin-α level and its association with predictors of atherosclerosis in a cohort of patients with RA. The study included 56 RA patients, 37 Behcets disease (BD) patients, and 29 healthy controls (HC). TNF-α, IL-6 and salusin-α levels, homeostasis model assessment (HOMA-IR) index and common carotid intima-media thickness (IMT) were determined. In the RA and BD groups, salusin-α levels (p<0.001 and p<0.01, respectively) and IMTs (p<0.001 for both) were higher compared to the HC group. However, the level of salusin-α was not directly associated with the IMT in all the groups. Serum salusin-α levels are increased in RA and BD, although they have increased IMT. Salusin-α has been reported to have anti-atherogenic effects in previous studies. However, it seems that salusin-α does not directly affect the atherogenesis in RA and BD. Further studies are needed to understand the regulation of salusin-α and determination of its relations with the predictors of atherosclerosis in RA and BD.

Impact of ghrelin on vitreous cytokine levels in an experimental uveitis model

Background The purpose of this study was to investigate the effect of intraperitoneal ghrelin on vitreous levels of interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-α) and to compare its effects with those of intraperitoneal infliximab in an experimental uveitis model. Methods Twenty-four male rats were assigned to four groups of six rats in each. All the rats, except for those in group 1 (controls), were injected intravitreally with concanavalin A to induce experimental uveitis. Rats in group 2 (sham) were not given any treatment after uveitis was induced. Rats in group 3 were given intraperitoneal infliximab 0.5 mg/100 mL on days 0, 1, 3, 5, and 7 following induction of uveitis on day 14 of the study. Rats in group 4 were given intraperitoneal ghrelin 10 ng/kg/day for 7 days following induction of uveitis. On day 21 of the study, enucleated globes were subjected to histopathologic examination. Vitreous levels of IL-1, IL-6, and TNF-α were measured by enzyme-linked immunosorbent assay. Results Vitreous levels of IL-1, IL-6, and TNF-α were significantly increased in the sham group relative to the control group (P < 0.05), but showed a significant decrease in the group treated with infliximab (P < 0.05). Cytokine levels also decreased in the ghrelin-treated group, but the decrease was not statistically significant (P > 0.05). Conclusion Ghrelin failed to decrease the IL-1, IL-6, and TNF-α levels that play a critical role in the pathogenesis of uveitis.

Methotrexate Has No Antifibrotic Effect in Bleomycin-induced Experimental Scleroderma

To the Editor: Scleroderma is a chronic inflammatory disease that is characterized by widespread microvascular damage and excessive deposition of collagen in the skin and internal organs, although its pathogenesis is not fully understood. Opinions regarding the current treatment of scleroderma are based on recently developed European League Against Rheumatism/EULAR Scleroderma Trials and Research Group recommendations. However, no disease-modifying drugs are currently available that can modify the course of the disease. In systemic sclerosis, methotrexate (MTX) has been studied in controlled trials, with controversial outcomes1,2. We evaluated the possible effectiveness of MTX in a bleomycin (BLM)-induced experimental scleroderma model3,4. Our study included 3 groups of mice (n = 10 Balb/c mice in each group). Control group mice … Address correspondence to Dr. S. Koca; E-mail: kocassk{at}yahoo.com

Pemetrexed ameliorates experimental arthritis in rats.

Pemetrexed (PMTX) is an anti-folate drug as methotrexate. The purpose of this study was to assess the efficacy of PMTX on collagen-induced arthritis (CIA). Forty Wistar albino rats were randomized into four groups. Arthritis was induced by intradermal injection of chicken type II collagen combined with incomplete Freund’s adjuvant. Animals were sacrificed at the 15th day after the onset of arthritis. Tumor necrosis factor alpha (TNF-α), interleukin (IL)-17, and malondialdehyde (MDA) levels were increased, and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities and the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were decreased in the arthritis group. In the PMTX-treated (0.2 and 1 mg/kg/week i.p.) groups, the levels of TNF-α, IL-17, and MDA were decreased; the activities of SOD, CAT, and GPx and the expressions of Nrf2 and HO-1 were restored, and perisynovial inflammation and cartilage–bone destruction were decreased. PMTX has anti-arthritic potential in the CIA model and may be a therapeutic agent for rheumatoid arthritis.

Ghrelin prevents the development of dermal fibrosis in bleomycin-induced scleroderma.

Scleroderma is a chronic inflammatory disease characterized by widespread fibrosis of the skin and the internal organs. Ghrelin is a polypeptide hormone produced by various tissues and inflammatory cells. In experimental studies, ghrelin has been shown to have anti‐inflammatory and antioxidant effects, in addition to its metabolic actions.