Publications (52)263.39 Total impact
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Article: Osteoprotegerin causes apoptosis of endothelial progenitor cells by induction of oxidative stress.
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ABSTRACT: OBJECTIVE: Elevated serum osteoprotegerin (OPG) represents an independent risk factor for atherosclerotic disease, although the underlying mechanism is not clear. Here, we investigated the association of serum OPG and circulating endothelial progenitor cells (EPCs) numbers, and explored the effect of OPG on EPCs apoptosis and its underlying mechanisms. METHODS: EPCs were enumerated in peripheral blood of 91 patients with systemic lupus erythematosus (SLE) using flow cytometry. Cultured EPCs, isolated from peripheral blood, were challenged with OPG and apoptosis was evaluated by TUNEL staining. Apoptosis related proteins were measured by quantitative real-time PCR (qPCR) and Western blot analysis. Reactive oxygen species (ROS) was detected by flow cytometry, and the expression of NADPH oxidase (Nox) and mitogen-activated protein kinases (MAPK) was measured by qPCR and Western blot analysis. RESULTS: Serum OPG level was independently associated with EPCs reduction in SLE patients. In vitro treatment of OPG significantly induced the apoptosis of EPCs. This effect was mediated by syndecan-4 on EPCs. OPG-induced apoptosis was abolished by ROS scavenger N-acetyl cysteine and Nox inhibitor diphenyleniodonium. OPG increased ROS production through activation of Nox2 and Nox4, and triggered phosphorylation of ERK1/2 and p38 MAPK. Quenching of ROS by knockdown of Nox2 or Nox4 transcripts inhibited phosphorylation of ERK1/2 and p38 MAPK. Moreover, inhibitors of ERK1/2 and p38 MAPK decreased ROS production and subsequent EPCs apoptosis, indicating a feed forward loop between Nox and MAPK to amplify ROS production related to apoptosis. CONCLUSION: Elevated OPG increases the apoptosis of EPCs by induction of oxidative stress. © 2013 American College of Rheumatology.Arthritis & Rheumatism 05/2013; · 7.87 Impact Factor -
Article: Association of Polymorphisms Modulating Low-density Lipoprotein Cholesterol with Susceptibility, Severity, and Progression of Rheumatoid Arthritis.
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ABSTRACT: OBJECTIVE: Dyslipidemia, a risk factor for cardiovascular diseases, is more prevalent in patients with rheumatoid arthritis (RA) than in the general population. We investigated whether single-nucleotide polymorphisms (SNP) modulating low-density lipoprotein (LDL) cholesterol affect susceptibility, severity, and progression of RA. METHODS: We enrolled 302 patients with RA and 1636 healthy controls, and investigated the SNP modulating LDL cholesterol. Clinical characteristics of RA, serum adipocytokine concentrations, and radiographic severity were analyzed according to genotype score based on the number of unfavorable alleles. The influence of genotype score on radiographic progression was also investigated using multivariable logistic models. RESULTS: We identified 3 SNP (rs688, rs693, and rs4420638) modulating LDL cholesterol in Koreans, which correlated well with LDL cholesterol levels in both patients with RA and controls. Among them, 2 SNP, rs688 and rs4420638, were more prevalent in patients with RA than in controls. In patients with RA carrying more unfavorable alleles (genotype score ≥ 3), disease activity measures, serum adipocytokine levels, and radiographic severity were all increased. The genotype score was an independent risk factor for radiographic progression of RA over 2 years, and its effect was greater than the influence of conventional risk factors. CONCLUSION: SNP modulating LDL cholesterol influence the risk, activity, and severity of RA. These results provide the first evidence that genetic mechanisms linked to dyslipidemia may directly contribute to the susceptibility and prognosis of RA, a representative of chronic inflammatory diseases, explaining the high incidence of dyslipidemia in RA.The Journal of Rheumatology 04/2013; · 3.69 Impact Factor -
Article: Thrombotic risk in patients with immune thrombocytopenia and its association with antiphospholipid antibodies.
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ABSTRACT: Patients with immune thrombocytopenia (ITP) paradoxically have an increased risk of thrombosis. The presence of antiphospholipid antibodies (aPL) has been observed in a substantial proportion of ITP patients, but its clinical significance remains to be established. This study retrospectively investigated the prevalence and clinical significance of aPL in ITP patients and assessed the risk factors for thrombosis. One hundred and sixty-five subjects with ITP were included in the study and followed for a mean period of 63·4 months. Sixty-nine (41·6%) patients were positive for aPL at diagnosis, and their clinical characteristics and course of ITP were not different from those of aPL-negative patients. Twenty-one (12·7%) patients developed a thrombotic event during follow-up and the cumulative incidence rate ratio of aPL-positive to aPL-negative patients for thromboembolism was 3·15 [95% confidence interval (CI) 1·21-8·17] after adjusting for confounding factors. Lupus anticoagulant and hypertension were identified by Cox regression analysis as independent risk factors for thrombosis [hazard ratio (HR) 4·1, 95% CI 1·4-11·9, P = 0·009 and HR 5·6, 95% CI 1·9-15·8, P = 0·001, respectively]. Our results showed that a substantial proportion of ITP patients were aPL-positive, and that lupus anticoagulant and hypertension were independent risk factors for thrombosis. Detection of aPL can provide useful information for identifying patients at high-risk for developing thrombosis.British Journal of Haematology 03/2013; · 4.94 Impact Factor -
Article: The APOM polymorphism as a novel risk factor for dyslipidaemia in rheumatoid arthritis: a possible shared link between disease susceptibility and dyslipidaemia.
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ABSTRACT: OBJECTIVES: A decrease in high-density lipoprotein (HDL) cholesterol during inflammation is common in many rheumatologic diseases, including rheumatoid arthritis (RA). Apolipoprotein M (apoM) is an apolipoprotein predominantly associated with HDL cholesterol. Recently, apoM polymorphisms have been related with RA susceptibility. We investigated the possible association between an APOM polymorphism and dyslipidaemia in Korean RA patients. METHODS: Two hundred and fifteen RA patients and 215 controls that provided complete genotyping were included. Genetic distribution, RA-associated phenotype, lipid profiles, and lipoproteins were evaluated. RESULTS: RA patients had increased frequencies of the APOM C-1065A A allele compared to the controls. RA patients with A/A genotypes had lower levels of HDL cholesterol than those with C/C genotypes. After adjustment for confounding factors, the A/A genotype was a risk factor for low HDL cholesterolaemia (OR=1.070, p=0.001). Subgroup analyses according to disease activity showed that the association between APOM genotype and HDL cholesterol levels was still significant in all subgroups, indicating that this APOM polymorphism may increase the dyslipidaemia risk, independently of RA disease activity. CONCLUSIONS: These data support that the APOM C-1065A polymorphism is associated with increased risk for developing RA and dyslipidaemia in RA patients. Reduced HDL cholesterol levels are independent of disease activity but are significantly influenced by APOM genotype. These findings suggest that a specific genetic factor for RA could be linked to dyslipidaemia and this could increase the risk of atherosclerosis in RA patients.Clinical and experimental rheumatology 11/2012; · 2.15 Impact Factor -
Article: Serum leptin levels are associated with the presence of syndesmophytes in male patients with ankylosing spondylitis.
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ABSTRACT: The aim of this study is to clarify the association between serum leptin levels and the presence of syndesmophytes in male patients with ankylosing spondylitis (AS). Seventy-two male patients with AS and 20 age-matched healthy male controls were included. Patients were stratified by the presence of syndesmophytes. Serum leptin levels were measured and adjusted for body mass index (BMI). In addition, bone-specific alkaline phosphatase (BALP), osteocalcin, and telopeptide of type I collagen were determined. Patients with syndesmophytes were associated with older age (p < 0.001), longer disease duration (p = 0.003), and higher BMI (p = 0.038). Serum leptin levels and leptin per BMI (leptin/BMI) ratio were not different between AS patients and healthy controls. However, serum leptin/BMI ratio was significantly higher in patients with syndesmophytes compared to those without (p = 0.010). In multivariate analysis, higher serum leptin/BMI ratio remained significantly associated with the presence of syndesmophytes (p = 0.029). Moreover, serum leptin/BMI ratio was positively correlated with serum BALP (γ = 0.279, p = 0.039). However, there was no significant association between serum leptin/BMI ratio and bone mineral density. Serum leptin levels are elevated in male AS patients with syndesmophytes and were found to be correlated with bone formation marker, suggesting a potential role of leptin in new bone formation in AS.Clinical Rheumatology 05/2012; 31(8):1231-8. · 2.00 Impact Factor -
Article: A novel pathogenic role of the ER chaperone GRP78/BiP in rheumatoid arthritis.
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ABSTRACT: An accumulation of misfolded proteins can trigger a cellular survival response in the endoplasmic reticulum (ER). In this study, we found that ER stress-associated gene signatures were highly expressed in rheumatoid arthritis (RA) synoviums and synovial cells. Proinflammatory cytokines, such as TNF and IL-1β, increased the expression of GRP78/BiP, a representative ER chaperone, in RA synoviocytes. RA synoviocytes expressed higher levels of GRP78 than osteoarthritis (OA) synoviocytes when stimulated by thapsigargin or proinflammatory cytokines. Down-regulation of Grp78 transcripts increased the apoptosis of RA synoviocytes while abolishing TNF- or TGF-β-induced synoviocyte proliferation and cyclin D1 up-regulation. Conversely, overexpression of the Grp78 gene prevented synoviocyte apoptosis. Moreover, Grp78 small interfering RNA inhibited VEGF(165)-induced angiogenesis in vitro and also significantly impeded synoviocyte proliferation and angiogenesis in Matrigel implants engrafted into immunodeficient mice. Additionally, repeated intraarticular injections of BiP-inducible factor X, a selective GRP78 inducer, increased synoviocyte proliferation and angiogenesis in the joints of mice with experimental OA. In contrast, mice with Grp78 haploinsufficiency exhibited the suppression of experimentally induced arthritis and developed a limited degree of synovial proliferation and angiogenesis. In summary, this study shows that the ER chaperone GRP78 is crucial for synoviocyte proliferation and angiogenesis, the pathological hallmark of RA.Journal of Experimental Medicine 03/2012; 209(4):871-86. · 13.85 Impact Factor -
Article: Low C3 levels is associated with neutropenia in a proportion of patients with myelodysplastic syndrome: retrospective analysis.
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ABSTRACT: Myelodysplastic syndrome (MDS) is a clonal disorder characterized by ineffective hematopoiesis. MDS patients are known to manifest overt rheumatic manifestations and have distinct immunological abnormalities but their clinical significance has yet to be elucidated. To investigate the prevalence of autoimmune or rheumatic manifestations in the course of MDS and serological immunological abnormalities which have been detected at presentation and to determine their clinical significance. One hundred and eleven patients diagnosed as having MSD between 2001 and 2004 were identified. Their clinical and serologic features on medical records were retrospectively reviewed. Of 111 patients with MDS, 25 showed 27 autoimmune or rheumatic manifestations. On dividing the cohort into two groups, with and without autoimmune or rheumatic manifestations, the two groups were not statistically different in survival. Serological immunological abnormalities were observed by variable rate, but had no association with compatible clinical manifestations. C3 hypocomplementemia was observed as high as 45.9% and the C3 hypocomplementemic subgroup had more severe cytopenia of red cell and white cell lineages and was dominant in the low-risk International Prognostic Scoring System category. Our data indicates that a distinct subset of MDS, demonstrating complement activation, has more severe cytopenias, which suggest complement activation contributes to the pathogenesis of autoimmune cytopenia in MDS.International Journal of Rheumatic Diseases 02/2012; 15(1):86-94. · 0.81 Impact Factor -
Article: Regulation of inflammatory responses and fibroblast-like synoviocyte apoptosis by calcineurin-binding protein 1 in mice with collagen-induced arthritis.
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ABSTRACT: Calcineurin-binding protein 1 (CABIN-1) regulates calcineurin phosphatase activity as well as the activation, apoptosis, and inflammatory responses of fibroblast-like synoviocytes (FLS), which actively participate in the chronic inflammatory responses in rheumatoid arthritis (RA). However, the mechanism of action of CABIN-1 in FLS apoptosis is not clear. This study was undertaken to define the regulatory role of CABIN-1 in FLS from mice with collagen-induced arthritis (CIA). Transgenic mice overexpressing human CABIN-1 in joint tissue under the control of a type II collagen promoter were generated. Expression of human CABIN-1 (hCABIN-1) in joints and FLS was determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. The expression of cytokines, matrix metalloproteinases (MMPs), and apoptosis-related genes in FLS was determined by enzyme-linked immunosorbent assay, gelatin zymography, and RT-PCR, respectively. Joints were stained with hematoxylin and eosin and with tartrate-resistant acid phosphatase for histologic analysis. Human CABIN-1-transgenic mice with CIA had less severe arthritis than wild-type mice with CIA, as assessed according to hind paw thickness and histologic features. The milder arthritis was accompanied by significantly enhanced apoptosis in transgenic mice, evidenced by a significantly greater number of TUNEL-positive cells in synovial tissue. Expression of inflammatory cytokines and MMPs in the transgenic mice with CIA was reduced, and they exhibited decreased Akt activation and increased expression of p53, caspase 3, caspase 9, and Bax. Our findings demonstrate that hCABIN-1 plays a critical role in promoting apoptosis of FLS and in attenuating inflammation and cartilage and bone destruction in RA. These results help elucidate the pathogenic mechanisms of RA and suggest that CABIN-1 is a potential target for treatment of this disease.Arthritis & Rheumatism 01/2012; 64(7):2191-200. · 7.87 Impact Factor -
Article: A systems approach to rheumatoid arthritis.
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ABSTRACT: Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily attacks synovial joints. Despite the advances in diagnosis and treatment of RA, novel molecular targets are still needed to improve the accuracy of diagnosis and the therapeutic outcomes. Here, we present a systems approach that can effectively 1) identify core RA-associated genes (RAGs), 2) reconstruct RA-perturbed networks, and 3) select potential targets for diagnosis and treatments of RA. By integrating multiple gene expression datasets previously reported, we first identified 983 core RAGs that show RA dominant differential expression, compared to osteoarthritis (OA), in the multiple datasets. Using the core RAGs, we then reconstructed RA-perturbed networks that delineate key RA associated cellular processes and transcriptional regulation. The networks revealed that synovial fibroblasts play major roles in defining RA-perturbed processes, anti-TNF-α therapy restored many RA-perturbed processes, and 19 transcription factors (TFs) have major contribution to deregulation of the core RAGs in the RA-perturbed networks. Finally, we selected a list of potential molecular targets that can act as metrics or modulators of the RA-perturbed networks. Therefore, these network models identify a panel of potential targets that will serve as an important resource for the discovery of therapeutic targets and diagnostic markers, as well as providing novel insights into RA pathogenesis.PLoS ONE 01/2012; 7(12):e51508. · 4.09 Impact Factor -
Article: Common variants at the promoter region of the APOM confer a risk of rheumatoid arthritis.
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ABSTRACT: Although the genetic component in the etiology of rheumatoid arthritis (RA) has been consistently suggested, many novel genetic loci remain to uncover. To identify RA risk loci, we performed a genome-wide association study (GWAS) with 100 RA cases and 600 controls using Affymetrix SNP array 5.0. The candidate risk locus (APOM gene) was re-sequenced to discover novel promoter and coding variants in a group of the subjects. Replication was performed with the independent case-control set comprising of 578 RAs and 711 controls. Through GWAS, we identified a novel SNP associated with RA at the APOM gene in the MHC class III region on 6p21.33 (rs805297, odds ratio (OR) = 2.28, P = 5.20 × 10-7). Three more polymorphisms were identified at the promoter region of the APOM by the re-sequencing. For the replication, we genotyped the four SNP loci in the independent case-control set. The association of rs805297 identified by GWAS was successfully replicated (OR = 1.40, P = 6.65 × 10-5). The association became more significant in the combined analysis of discovery and replication sets (OR = 1.56, P = 2.73 × 10-10). The individuals with the rs805297 risk allele (A) at the promoter region showed a significantly lower level of APOM expression compared with those with the protective allele (C) homozygote. In the logistic regressions by the phenotype status, the homozygote risk genotype (A/A) consistently showed higher ORs than the heterozygote one (A/C) for the phenotype-positive RAs. These results indicate that APOM promoter polymorphisms are significantly associated with the susceptibility to RA.Experimental and Molecular Medicine 08/2011; 43(11):613-21. · 2.48 Impact Factor -
Article: The efficacy of tramadol/acetaminophen combination tablets (Ultracet®) as add-on and maintenance therapy in knee osteoarthritis pain inadequately controlled by nonsteroidal anti-inflammatory drug (NSAID).
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ABSTRACT: The purpose of this study is to compare the efficacy of tramadol 37.5 mg/acetaminophen 325 mg combination tablets (tramadol/APAP) with that of nonsteroidal anti-inflammatory drugs (NSAIDs) as maintenance therapy following tramadol/APAP and NSAID combination therapy in knee osteoarthritis (OA) pain which was inadequately controlled by NSAIDs. Subjects with knee OA for over 1 year and moderate pain (numerical rating scale [NRS] ≥5) despite at least 4 weeks' NSAID therapy (meloxicam 7.5 mg or 15 mg qd or aceclofenac 100 mg bid) received tramadol/APAP add-on (combination with NSAID) for 4 weeks. Thereafter, subjects with significant pain improvement (NRS <4) were randomized to receive either tramadol/APAP or NSAID for 8 weeks. On days 29 and 57, Western Ontario and McMaster Universities (WOMAC) OA index score was measured. Secondary measures included pain intensity (NRS), pain relief score, and subjects' and investigators' overall medication assessments. Of 143 subjects enrolled, 112 completed the 4-week tramadol/APAP and NSAID combination phase and 97 (67.8%) experienced significant pain improvement. Of the 97 subjects randomized, 36 in tramadol/APAP group and 47 in NSAID group completed the 8-week comparator study. On days 29 and 57, WOMAC scores and pain intensities did not increase in both groups compared to measurements immediately after the combination therapy. At these two time points, there were no significant differences in WOMAC scores, pain intensities, and other secondary measures between the two groups. Overall adverse event rates were similar in both groups. Tramadol/APAP add-on significantly improved knee OA pain which had been inadequately controlled by NSAIDs. In those subjects who showed favorable response to tramadol/APAP and NSAID combination therapy, both tramadol/APAP and NSAIDs were effective at maintaining the pain-reduced state and there was no significant difference in efficacy between tramadol/APAP and NSAIDs.Clinical Rheumatology 08/2011; 31(2):317-23. · 2.00 Impact Factor -
Article: Suppression of neovascularization and experimental arthritis by D-form of anti-flt-1 peptide conjugated with mini-PEG(™).
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ABSTRACT: Extensive angiogenesis in the synoviums is a characteristic pathology of rheumatoid arthritis (RA). We have demonstrated that anti-flt-1 hexapeptide, GNQWFI, specifically inhibits the interaction of VEGF or PlGF with its receptor flt-1 (Yoo et al. [13]). In this study, we investigate the feasibility of the synthetic D-form of anti-flt-1 hexapeptide conjugated with 8-amino-3,6-dioxaoctanoic acid (mini-PEG™) for treatment of RA. We first modified the structure of anti-flt-1 peptide from the L-form (GNQWFI) to all D-form (gnqwfi; allD) and then conjugated allD with mini-PEG™ to enhance its stability. The result showed that the allD anti-flt-1 peptide showed an increased stability in the sera without major loss of inhibitory activity. The allD and its mini-PEGylated derivative similarly suppressed wounding migration, chemotaxis, and tube formation of endothelial cells in vitro. However, in the Matrigels assay, the in vivo anti-angiogenic activity of mini-PEGylated allD was stronger than that of native allD or L-form. Moreover, oral and subcutaneous administration of mini-PEGylated allD, but not oral feeding of original L-form, successfully suppressed severity of collagen-induced arthritis. After a single subcutaneous injection, the Cy5-labeled mini-PEGylated allD was found to be distributed systemically and accumulated in arthritic joints of mice, particularly in joints with a severe clinical score. In conclusion, our data suggests that mini-PEGylated allD is more beneficial in the treatment of RA than unmodified anti-flt-1 peptides, since it has increased stability and the possibility of oral delivery, and could be applied to treat angiogenesis-dependent human diseases, including RA.Angiogenesis 07/2011; 14(4):431-42. · 6.06 Impact Factor -
Article: NF-AT5 is a critical regulator of inflammatory arthritis.
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ABSTRACT: To investigate the role of NF-AT5, an osmoprotective transcription factor, in synovial hyperplasia and angiogenesis in patients with rheumatoid arthritis (RA). The expression of NF-AT5 in synovial tissue and synoviocytes from RA patients was examined by immunohistochemistry and Western blot analysis, respectively. Messenger RNA (mRNA) in RA synoviocytes and human umbilical vein endothelial cells (HUVECs) transfected with dummy small interfering RNA (siRNA) or NF-AT5 siRNA were profiled using microarray technology. Assays to determine synoviocyte apoptosis and proliferation were performed in the presence of NF-AT5 siRNA. VEGF₁₆₅-induced angiogenesis was assessed by measuring the proliferation, tube formation, and wound migration of HUVECs. Experimental arthritis was induced in mice by injection of anti-type II collagen antibody. NF-AT5 was highly expressed in rheumatoid synovium, and its activity was increased by proinflammatory cytokines, such as interleukin-1β and tumor necrosis factor α. The mRNA profiling of synoviocytes and HUVECs transfected with NF-AT5-targeted siRNA revealed 3 major changes in cellular processes associated with the pathogenesis of RA: cell cycle and survival, angiogenesis, and cell migration. Consistent with these results, NF-AT5 knockdown in RA synoviocytes and HUVECs inhibited their proliferation/survival and impeded angiogenic processes in HUVECs. Mice with NF-AT5 haploinsufficiency (NF-AT5(+/-)) developed a very limited degree of synovial proliferation, as seen on histologic analysis, and decreased angiogenesis, and they exhibited a nearly complete suppression of experimentally induced arthritis. NF-AT5 regulates synovial proliferation and angiogenesis in chronic arthritis.Arthritis & Rheumatism 07/2011; 63(7):1843-52. · 7.87 Impact Factor -
Article: Simultaneous presentation of hemophagocytic syndrome and mesenteric vasculitis in a patient with systemic lupus erythematosus.
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ABSTRACT: We report an 18-year old female patient with systemic lupus erythematosus (SLE), who developed fever, pancytopenia, abdominal pain, and watery diarrhea. Computed tomography (CT) and bone marrow aspirate revealed lupus mesenteric vasculitis (LMV) and hemophagocytic syndrome (HPS). Serologic tests for Epstein-Barr virus (EBV) indicated its reactivation. This case demonstrates that HPS and concomitant LMV associated with viral reactivation can occur as clinical manifestations of SLE flare.Modern Rheumatology 01/2011; 21(3):330-3. · 1.58 Impact Factor -
Article: NFAT5 is a critical regulator of inflammatory arthritis.
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ABSTRACT: OBJECTIVE.: To investigate the role of nuclear factor of activated T cells 5 (NFAT5), which is known as an osmoprotective transcription factor, in synovial hyperplasia and angiogenesis in rheumatoid arthritis (RA) METHODS.: Expression of NFAT5 was examined in the synovial tissues and synoviocytes of RA patients using immunohistochemistry and Western blot analysis, respectively. The mRNAs of RA synoviocytes and human umbilical vein endothelial cells (HUVEC) transfected with dummy siRNA or NFAT5 siRNA were profiled using microarray technology. Assays to determine synoviocyte apoptosis and proliferation were performed in the presence of NFAT5 siRNA.VEGF(165)-induced angiogenesis was assessed by measuring the proliferation, tube formation, and wounding migration of HUVEC. Experimental arthritis was induced in mice by injection of anti-type II collagen antibody. RESULTS.: NFAT5 was highly expressed in the rheumatoid synovium and its activity was increased by proinflammatory cytokines, such as IL-1β and TNF-α. The mRNA profiling of synoviocytes and HUVEC transfected with NFAT5-targeted siRNA revealed three major changes in cellular processes associated with the pathogenesis of RA: cell cycle and survival, angiogenesis, and cell migration. Consistent with these results, NFAT5 knock-down in RA synoviocytes and HUVEC inhibited their proliferation/survival and impeded angiogenic processes in HUVEC. Mice with NFAT5 haplo-insufficiency (NFAT5(+/-)) developed very limited degree of synovial proliferation in histological analysis, decreased angiogenesis, and exhibited a nearly complete suppression of experimentally induced arthritis. CONCLUSION.: NFAT5 regulates synovial proliferation and angiogenesis in chronic arthritis.Arthritis & Rheumatism 01/2011; · 7.87 Impact Factor -
Article: Inhibition of synovial hyperplasia, rheumatoid T cell activation, and experimental arthritis in mice by sulforaphane, a naturally occurring isothiocyanate.
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ABSTRACT: To investigate whether sulforaphane (SFN), an isothiocyanate derived from cruciferous vegetables such as broccoli, regulates synoviocyte hyperplasia and T cell activation in rheumatoid arthritis (RA). Synoviocyte survival was assessed by MTT assay. The levels of Bcl-2, Bax, p53, and pAkt were determined by Western blot analysis. Cytokine concentrations in culture supernatants from mononuclear cells were analyzed by enzyme-linked immunosorbent assay. The in vivo effects of SFN were examined in mice with experimentally induced arthritis. SFN induced synoviocyte apoptosis by modulating the expression of Bcl-2/Bax, p53, and pAkt. In addition, nonapoptotic doses of SFN inhibited T cell proliferation and the production of interleukin-17 (IL-17) and tumor necrosis factor alpha (TNFalpha) by RA CD4+ T cells stimulated with anti-CD3 antibody. Anti-CD3 antibody-induced increases in the expression of retinoic acid-related orphan receptor gammat and T-bet were also repressed by SFN. Moreover, the intraperitoneal administration of SFN to mice suppressed the clinical severity of arthritis induced by injection of type II collagen (CII), the anti-CII antibody levels, and the T cell responses to CII. The production of IL-17, TNFalpha, IL-6, and interferon-gamma by lymph node cells and spleen cells from these mice was markedly reduced by treatment with SFN. Anti-CII antibody-induced arthritis in mice was also alleviated by SFN injection. SFN was found to inhibit synovial hyperplasia, activated T cell proliferation, and the production of IL-17 and TNFalpha by rheumatoid T cells in vitro. The antiarthritic and immune regulatory effects of SFN, which were confirmed in vivo, suggest that SFN may offer a possible treatment option for RA.Arthritis & Rheumatism 01/2010; 62(1):159-70. · 7.87 Impact Factor -
Article: Anti-neuropilin-1 peptide inhibition of synoviocyte survival, angiogenesis, and experimental arthritis.
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ABSTRACT: To delineate the role of neuropilin-1 (NP-1), a vascular endothelial growth factor receptor (VEGFR), in rheumatoid inflammation and to determine whether blockade of NP-1 could suppress synoviocyte survival and angiogenesis. VEGF(111-165) peptide, which encompasses the NP-1 binding domain of VEGF(165), was generated by cleaving VEGF(165) with plasmin. The effect of this peptide on the interaction between VEGF(165) and its receptor was determined by (125)I-VEGFR binding assay. Assays to determine synoviocyte apoptosis, adhesion, and migration were performed in the presence of VEGF(165) and/or the peptide. VEGF(165)-induced angiogenesis was assessed by measuring the proliferation, tube formation, and wounding migration of endothelial cells (ECs). Mice were immunized with type II collagen to induce experimental arthritis. VEGF(111-165) peptide specifically inhibited the binding of (125)I-VEGF(165) to NP-1 on rheumatoid synoviocytes and ECs. The peptide eliminated the VEGF(165)-mediated increase in synoviocyte survival and activation of p-ERK and Bcl-2. The peptide also completely inhibited a VEGF(165)-induced increase in synoviocyte adhesion and migration. In addition, the anti-NP-1 peptide blocked VEGF(165)-stimulated proliferation, capillary tube formation, and wounding migration of ECs in vitro. VEGF(165)-induced neovascularization in a Matrigel plug in mice was also blocked by treatment with the peptide. Finally, subcutaneous injection of anti-NP-1 peptide suppressed arthritis severity and autoantibody formation in mice with experimental arthritis and inhibited synoviocyte hyperplasia and angiogenesis in arthritic joints. Anti-NP-1 peptide suppressed VEGF(165)-induced increases in synoviocyte survival and angiogenesis, and thereby blocked experimental arthritis. Our findings suggest that anti-NP-1 peptide could be useful in alleviating chronic arthritis.Arthritis & Rheumatism 01/2010; 62(1):179-90. · 7.87 Impact Factor -
Article: Phase 2 enzyme inducer sulphoraphane blocks matrix metalloproteinase production in articular chondrocytes.
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ABSTRACT: In addition to its chemopreventive activity, phase 2 enzyme inducers have been recently found to have anti-inflammatory activity. In this study, we examined the influence of sulphoraphane (SPN), one of the most potent inducers of the phase II enzymes on the production of MMPs by pro-inflammatory cytokines in human articular chondrocytes. Articular cartilages were obtained from knee OA patients and were cultured in monolayers and explants. Induction of a phase II enzyme, NAD(P)H:quinone oxidoreductase 1 (NQO1), in chondrocytes was assayed after incubation with various concentrations of SPN. Chondrocytes were stimulated with IL-1 or TNF-alpha with or without pre-incubation with SPN. The expression and activation of MMP-1, -3 and -13 was evaluated by an ELISA, gel zymography and RT-PCR. MAP kinases [p38, extracellular signal-regulated protein kinase (ERK) and C-Jun N terminal kinase (JNK)] and NF-kappaB activation were evaluated by western blotting and by an electrophoretic mobility shift assay, respectively. SPN significantly induced NQO1 activity in chondrocytes and the induction was maximal at 24 h. SPN inhibited the production of MMP-1, -3 and -13 protein and mRNA induced by either IL-1 or TNF-alpha in a dose-dependent manner. This inhibition of MMP by SPN was accompanied by the inhibition of NF-kappaB and JNK activation. SPN was found to inhibit MMP production in pro-inflammatory cytokine-stimulated chondrocytes. Delineation of the biochemical mechanism regulating cartilage catabolism by SPN may identify safe and effective therapeutic targets for the inhibition of cartilage degradation.Rheumatology (Oxford, England) 07/2009; 48(8):932-8. · 4.24 Impact Factor -
Article: Role of placenta growth factor and its receptor flt-1 in rheumatoid inflammation: a link between angiogenesis and inflammation.
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ABSTRACT: To investigate the direct effects of placenta growth factor (PlGF) and its specific receptor, flt-1, which are known to mediate angiogenesis, on the inflammatory process of rheumatoid arthritis (RA). Expression of PlGF and flt-1 in the synovial tissue of RA patients was examined using immunohistochemistry. Enzyme-linked immunosorbent assay was used to determine the concentrations of PlGF, tumor necrosis factor alpha (TNFalpha), and interleukin-6 (IL-6) in culture supernatants of either mononuclear cells or synoviocytes. The flt-1 expression level in mononuclear cells was analyzed by flow cytometry. Experimental arthritis was induced in mice either by immunization with type II collagen (CII) or by injection of anti-CII antibody. PlGF was highly expressed in the synovium of RA patients, and its primary source was fibroblast-like synoviocytes (FLS). When stimulated with IL-1beta, FLS from RA patients produced higher amounts of PlGF than did FLS from patients with osteoarthritis. Exogenous PlGF specifically increased the production of TNFalpha and IL-6 in mononuclear cells from RA patients (but not those from healthy controls) via a calcineurin-dependent pathway. The response to PlGF was associated with increased expression of flt-1 on RA monocytes, which could be induced by IL-1beta and TNFalpha. A novel anti-flt-1 hexapeptide, GNQWFI, abrogated the PlGF-induced increase in TNFalpha and IL-6 production, and also suppressed CII-induced arthritis and serum IL-6 concentrations in mice. Moreover, genetic ablation of PlGF prevented the development of anti-CII antibody-induced arthritis in mice. Our data suggest that enhanced expression of PlGF and flt-1 may contribute to rheumatoid inflammation by triggering production of proinflammatory cytokines. The use of the novel anti-flt-1 peptide, GNQWFI, may be an effective strategy for the treatment of RA.Arthritis & Rheumatism 02/2009; 60(2):345-54. · 7.87 Impact Factor -
Article: Role of placenta growth factor and its receptor flt‐1 in rheumatoid inflammation: A link between angiogenesis and inflammation
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ABSTRACT: Objective To investigate the direct effects of placenta growth factor (PlGF) and its specific receptor, flt-1, which are known to mediate angiogenesis, on the inflammatory process of rheumatoid arthritis (RA).Methods Expression of PlGF and flt-1 in the synovial tissue of RA patients was examined using immunohistochemistry. Enzyme-linked immunosorbent assay was used to determine the concentrations of PlGF, tumor necrosis factor α (TNFα), and interleukin-6 (IL-6) in culture supernatants of either mononuclear cells or synoviocytes. The flt-1 expression level in mononuclear cells was analyzed by flow cytometry. Experimental arthritis was induced in mice either by immunization with type II collagen (CII) or by injection of anti-CII antibody.ResultsPlGF was highly expressed in the synovium of RA patients, and its primary source was fibroblast-like synoviocytes (FLS). When stimulated with IL-1β, FLS from RA patients produced higher amounts of PlGF than did FLS from patients with osteoarthritis. Exogenous PlGF specifically increased the production of TNFα and IL-6 in mononuclear cells from RA patients (but not those from healthy controls) via a calcineurin-dependent pathway. The response to PlGF was associated with increased expression of flt-1 on RA monocytes, which could be induced by IL-1β and TNFα. A novel anti–flt-1 hexapeptide, GNQWFI, abrogated the PlGF-induced increase in TNFα and IL-6 production, and also suppressed CII-induced arthritis and serum IL-6 concentrations in mice. Moreover, genetic ablation of PlGF prevented the development of anti-CII antibody–induced arthritis in mice.Conclusion Our data suggest that enhanced expression of PlGF and flt-1 may contribute to rheumatoid inflammation by triggering production of proinflammatory cytokines. The use of the novel anti–flt-1 peptide, GNQWFI, may be an effective strategy for the treatment of RA.Arthritis & Rheumatism 01/2009; 60(2):345 - 354. · 7.87 Impact Factor
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2001–2013
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Catholic University of Korea
- • Research Institute of Immunobiology
- • Department of Internal Medicine
Seoul, Seoul, South Korea
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2012
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Saint Vincent Hospital
Worcester, MA, USA
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2002
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St Mary's Hospital NHS
Newport, ENG, United Kingdom
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