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ID PMID Title PublicationDate abstract
16418805 COX-2 inhibitors modulate IL-12 signaling through JAK-STAT pathway leading to Th1 response 2006 Jan Experimental allergic encephalomyelitis (EAE) is a Th1 cell-mediated autoimmune disease model of multiple sclerosis (MS). IL-12 plays a crucial role in the pathogenesis of EAE/MS and inhibition of IL-12 production or IL-12 signaling was effective in preventing EAE. Cyclooxygenase (COX-2) is a key enzyme promoting inflammation in rheumatoid arthritis and tumor induced angiogenesis. Recent studies have shown that COX-2 inhibitors prevent EAE, however, their mechanism of action is not fully understood. In this study, we show that in vivo treatment (i.p.) with 100 mug COX-2 selective inhibitors (LM01, LM08, LM11, and NS398), on every other day from day 0 to 30, significantly reduced the incidence and severity of EAE in SJL/J and C57BL/6 mice. Further analyses showed that the COX-2 inhibitors reduced neural antigen-induced IL-12 production, T cell proliferation and Th1 differentiation ex vivo and in vitro. The COX-2 inhibitors also decreased IL-12-induced T cell responses through blocking tyrosine phosphorylation of JAK2, TYK2, STAT3, and STAT4 proteins in T cells. These results demonstrate that COX-2 inhibitors ameliorate EAE in association with the modulation of IL-12 signaling through JAK-STAT pathway leading to Th1 differentiation and suggest their use in the treatment of MS and other Th1 cell-mediated autoimmune diseases.
16204471 Periplocoside E, an effective compound from Periploca sepium Bge, inhibited T cell activat 2006 Feb Periploca sepium Bge, a traditional Chinese herb medicine, is used for treating rheumatoid arthritis in China. Followed the bioactivity-guided isolation, the most potent immunosuppressive compound, periplocoside E (PSE), a pregnane glycoside, had been identified from P. sepium Bge. We investigated the immunosuppressive effects of PSE in vitro and in vivo. The results showed that PSE in a dose-dependent manner significantly inhibited the proliferation of splenocytes induced by concanavalin A and mixed lymphocyte culture reaction at no cytotoxic concentrations (<5 microM). Administration of PSE suppressed a delayed-type hypersensitivity reaction, and ovalbumin (OVA) induced antigen-specific immune responses in mice. In vivo treatment with PSE dose dependently suppressed OVA-induced proliferation and cytokine [interleukin (IL)-2 and interferon (IFN)-gamma] production from splenocytes in vitro. Purified T cells from OVA-immunized mice with PSE treatment showed its low ability for activation by OVA plus normal antigen presenting cell stimulation again in vitro. Further studies showed PSE dose dependently inhibited anti-CD3-induced primary T cell proliferation, activation for IL-2Ralpha (CD25) expression, and cytokine (IFN-gamma and IL-2) production also at the transcriptional level. PSE was highly specific and significantly inhibited the activation of extracellular signal-regulated kinase and Jun N-terminal kinase, whereas activation of p38 was not affected in T cells stimulated with anti-CD3. These results demonstrated that PSE is an immunosuppressive compound in P. sepium Bge, which directly inhibits T cell activation in vitro and in vivo. This study provided evidence to understand the therapeutic effects of P. sepium Bge and indicated that this herb is appropriate for treatment of T cell-mediated disorders, such as autoimmune diseases.
15952021 Frequent prescribing of drugs with potential gastrointestinal toxicity among continuous us 2005 Jul OBJECTIVE: A number of drugs used concurrently with non-steroidal anti-inflammatory drugs (NSAIDs) increase the risk of gastrointestinal (GI) haemorrhage. We studied the prescribing of NSAIDs with corticosteroids, oral anticoagulants or selective serotonin re-uptake inhibitors (SSRIs), as well as the use of gastroprotection among continuous and non-continuous users of NSAIDs in Finland. METHODS: Concurrent use of various drugs was analysed in a nested case-control study in a population-based cohort of NSAID users in 2000 using data in the National Prescription Database. RESULTS: Prescribing of any other drug with the potential to increase the risk of GI bleeding with NSAIDs was five times [5.2; 95% confidence interval (CI) 4.7-5.9] more common among continuous than non-continuous NSAID users, and the odds ratio for oral corticosteroids was 8.0 (95% CI 6.6-9.6). Of patients using continuous NSAIDs with oral corticosteroids, 73.3% had rheumatoid arthritis (RA). After excluding RA patients, the odds ratio remained high (4.5; 95% CI 3.3-6.1) and at the same level as for SSRIs (3.7; 3.1-4.4). Gastroprotective drugs were prescribed for 6.8% of the continuous users of NSAIDs alone, and for 20.4% of patients taking any of the studied drug combinations with NSAIDs. The continuous users of NSAIDs alone had gastroprotection 2.9 (2.5-3.3) times more often than other users of NSAIDs. With drug combinations (NSAID+corticosteroid, NSAID+SSRI, NSAID+anticoagulants), the use of gastroprotection did not differ from patients using lower amounts of NSAIDs. CONCLUSIONS: When prescribing NSAIDs, situations leading to habitual use should be avoided, potential complications due to clustering of risk factors recognised, and gastroprotection prescribed for patients with increased risk of GI haemorrhage.
17228672 [Intraoperative imaging to monitor prosthetic fixation for total hip arthroplasty]. 2006 Dec OBJECTIVE: To explore the intraoperative imaging to monitor the prosthetic fixation for the total hip arthroplasty (THA) and to increase the accuracy of the primary THA prosthetic fixation. METHODS: From April 2000 to August 2005, 69 patients (75 hips) underwent THA monitored by the imaging (the imaged THA group, Group I), and 72 patients (78 hips) underwent THA with the standard method (the standard THA group, Group S). There were 32 72 patients (78 hips) underwent THA with the standard method (the standard THA group s in Group S). There were 32 males and 37 females in Group S. The mean ages of the patients in Group I and Group S were 62. 3 years and 60. 5 years respectively, ranging 46-75 years in Group I and 43-75 years in Group S. Preoperative diagnoses were femoral neck fractal measure (Garden III, IV ) in 23 patients (23 hips) in Group and 2 5 patients (25 hips) in Group S, acetabular dysplasia Campbell I , II) in 9 patients (10 hips) in Group I and 11 patients (13 hips) in Group S osteoarthritis in 16 patients (17 hips) in Group I and 15 patients (15 hips) in Group S, femoral head osteonecrosis (Ficat III, IV ) 15 patients (16 hips) in Group I and 17 patients (17 hips) in Group S, and rheumatoid arthritis in 6 patients (9 hips) in Group I and 4 patients (8 hips) in Group S. There were 21 hips of cement prostheses in Group I and 22 hips in Group ferative 12 hips of cementless prostheses in Group I and 11 hips in Group S, 42 hips of cement and cementless prostheses in Group I and 45 hips in Group S. Group I used the standard THA and the intraoperative X-ray monitoring the prosthetic fixation in the numerical measure of abduction angle, anteversion angle, femoral neck length, and femoral offset distance. The items compared between Group I and Group S included incisional length, intraoperative bleeding, transfusion, operative time, frequency of X-ray imaging, infection, postoperative functional recovery, and prosthetic position of postoperative X-ray imaging. RESULTS The follow-up on 62 patients in Group I and 64 patients in Group S for 6-64 months averaged 42 months revealed that there were statistically significant differences in incisional length, intraoperative bleeding. transfusion, operative time, frequency of X-ray imaging, postoperative functional recovery, prosthetic position of postoperative X-ray imaging, and the Harris score between Group I and Group S one year after operation. The results of Group I were significatnly better than those of Group S. CONCLUSION: The intraoperative X-ray imaging can increase the accuracy of the THA prosthetic fixation and reduce the incidence of THA maloperation by The X-ray imaging can also be used in county hospitals if C-arm fluoroscopy can be provided.
16702601 Conjugated linoleic acid inhibits osteoclast differentiation of RAW264.7 cells by modulati 2006 Aug Bone destruction is a pathological hallmark of several chronic inflammatory diseases, including rheumatoid arthritis, periodontitis, and osteoporosis. Inflammation-induced bone loss of this sort results from increased numbers of bone-resorbing osteoclasts. Numerous studies have indicated that conjugated linoleic acid (CLA) positively influences calcium and bone metabolism. Gene-deletion studies have shown that receptor activator of nuclear factor-kappaB ligand (RANKL) is one of the critical mediators of osteoclastogenesis. In this report, we examine the ability of CLA to suppress RANKL signaling and osteoclastogenesis in RAW264.7 cells, a murine monocytic cell line. Treatment of these cells with RANKL activated nuclear factor-kappaB (NF-kappaB), and preexposure of the cells to CLA significantly suppressed RANKL-induced NF-kappaB activation, including phosphorylation of I-kappaBalpha, degradation of I-kappaBalpha, and nuclear translocation of p65. RANKL induced osteoclastogenesis in these monocytic cells, and CLA inhibited RANKL-induced tumor necrosis factor-alpha production and osteoclast differentiation, including osteoclast-specific genes such as tartrate-resistant acid phosphatase, cathepsin K, calcitonin receptor, and matrix metalloproteinase-9 expression and osteoclast-specific transcription factors such as c-Fos, nuclear factor of activated T-cells expression, and bone resorption pit formation. CLA also inhibited RANKL-induced activation of mitogen-activated protein kinase p38 but had little effect on c-Jun N-terminal kinase activation. Collectively, these data demonstrate for the first time that CLA inhibits osteoclastogenesis by modulating RANKL signaling. Thus, CLA may have important therapeutic implications for the treatment of bone diseases associated with enhanced bone resorption by excessive osteoclastogenesis.
16882186 Male New Zealand Black/KN mice: a novel model for autoimmune-induced permanent alopecia? 2006 Aug BACKGROUND: Irreversible, permanent and scarring alopecia is associated with several autoimmune diseases, including all autoimmune connective tissue disorders. The pathogenesis of autoimmune-induced permanent alopecia (APA) is still poorly understood, and instructive, simple mouse models for the study of APA are needed urgently. During the course of our studies in a well-established mouse model for chronic rheumatoid arthritis, the New Zealand Black/KN (NZB/KN) mouse, we noticed that ageing male NZB/KN mice developed spontaneous APA. OBJECTIVES: To study whether alopecia seen in ageing male NZB/KN mice displays key features of human APA and may, thus, be a useful new mouse model for clinically relevant APA research. METHODS: NZB/KN, the F1 hybrid of NZW/N Slc x NZB/KN (W/BKN F1), the F1 hybrid of NZB/KN x NZW/N Slc (BKN/W F1), and the F2 hybrid of W/BKN F1 x W/BKN F1 mice were employed in this study, in order to check which strain carries the highest risk of alopecia development. Besides routine histology, CD3, CD4 and CD8 expression as well as immunoglobulin (Ig) G and IgM deposition in hair follicles were investigated by immunohistology/immunofluorescence. Mast cell distribution/degranulation and Ki-67 (proliferation)/TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling) (apoptosis) positive cells were also analysed. RESULTS: Only F2 male NZB/KN mice were prone to develop alopecia, suggesting that Y chromosome-associated gene(s) are involved in the pathogenesis of APA, which incidence rises with increasing age. The lesional alopecia skin in 12-month-old male NZB/KN mice showed a sharp decline in hair follicle density, thus meeting a key criterion of permanent alopecia. Both macroscopically and histologically, the alopecia seen in these mice resembled in many respects different stages of clinical APA, such as alopecia associated with chronic discoid lupus erythematosus (DLE) in humans. Lesional APA hair follicles in mice displayed intrafollicular and perifollicular mononuclear cell infiltrates, as well as an increased number of activated (degranulated) perifollicular mast cells. In the fully developed lesion, many CD4+ cells were seen in perifollicular locations, including the epithelial stem cell region (bulge), and also contained a few CD8+ T cells. IgM deposits were found in the follicular basement membrane zone (BMZ). Both in the bulge and the hair matrix region of the affected anagen hair follicles, there were signs of massive keratinocyte apoptosis. CONCLUSIONS: Our currently available data suggest that male but not female NZB/KN mice may indeed represent a suitable mouse model for APA, with some similarities to the permanent alopecia seen in human DLE patients, although additional and confirmatory investigations are needed before this mouse strain can be accepted as a murine equivalent of APA in humans.
16755666 Implication of prostaglandin receptors in the accumulation of osteoprotegerin in human ost 2006 Jun OBJECTIVE: Prostaglandins are important mediators in bone metabolism and in pathologies such as rheumatoid arthritis and osteoarthritis. We investigated the roles of cyclooxygenases (COX) and prostaglandin receptors in the accumulation of osteoprotegerin (OPG) in the supernatants of human osteoblasts in culture. METHODS: Three different cellular models were used, the human osteosarcoma cell lines MG-63 and Saos-2, and primary cultures of human osteoblasts. OPG concentrations were determined by ELISA. RESULTS: RT-PCR analysis showed that, like primary human osteoblasts, MG-63 cells express DP, EP4, FP, IP, and TP receptors, whereas the Saos-2 cells lack IP. Concentration of OPG was highest in MG-63 cell supernatants (36 +/- 12.5 ng/ml), followed by human osteoblasts (12.77 +/- 2.2 ng/ml) and Saos-2 (3.6 +/- 0.76 ng/ml). COX inhibitors did not alter these values. Prostaglandin E2 and BW 245C (a synthetic DP receptor agonist) decreased OPG in the supernatants of human osteoblasts but not in immortalized cell lines. These effects were concentration-dependent and were inhibited by EP4 and DP receptor antagonists. Fluprostenol, an FP receptor agonist, increased the accumulation of OPG in MG-63 but not in primary human osteoblasts or Saos-2. CONCLUSION: Our results show that activation of EP4 or DP receptors decreased the accumulation of OPG in supernatants of osteoblasts in culture, and suggest that these receptors could be interesting pharmacological targets in bone diseases. They also demonstrate important differences between primary osteoblasts and immortalized cell lines, both in the distribution and in the effects mediated by prostaglandin receptors.
16644488 Reduction of lipopolysaccharide-induced interleukin-6 production by the kappa opioid U50,4 2006 Jun Several studies demonstrate that opioids modulate the immune response via opioid receptors expressed directly on the immune cells themselves. Recently, it has been suggested that the kappa opioid system has a modulatory role in various inflammatory diseases including rheumatoid arthritis. This modulation may occur via changes in cytokine secretion by monocyte-derived cells. To further study this opioid-immune relationship, we stimulated P388D1 cells, a mouse monocyte-like cell line, with lipopolysaccharide (LPS) in the presence or absence of the kappa opioid-selective ligand, U50,488. Pretreatment with U50,488 significantly reduced LPS-stimulated interleukin-6 (IL-6) production as measured by ELISA. This effect was mediated by the kappa opioid receptor, because nor-binaltorphimine (nor-BNI), a kappa-selective antagonist, blocked this inhibition. It is likely that this reduction of IL-6 protein by U50,488 treatment is attributed to decreases in IL-6 mRNA. RT-PCR experiments demonstrated that U50,488 treatment significantly reduced the LPS-mediated increase in IL-6 mRNA and that this effect was also blocked by nor-BNI. Understanding the mechanism behind the reduction of proinflammatory cytokine production by opioids may lead to the development of more effective therapeutics for inflammatory diseases.
16571771 IFN-beta-induced SOCS-1 negatively regulates CD40 gene expression in macrophages and micro 2006 May Costimulation between T cells and antigen-presenting cells is required for adaptive immune responses. CD40, a costimulatory molecule, is expressed in macrophages and microglia. The aberrant expression of CD40 is involved in human diseases including multiple sclerosis, rheumatoid arthritis, and Alzheimer's disease. CD40 expression is induced by a variety of stimuli, including IFN-gamma and lipopolysaccharide (LPS). In this study, we describe the molecular basis by which IFN-beta, a cytokine with immunomodulatory properties, regulates CD40 gene expression. IFN-beta induces CD40 expression in macrophages and microglia at the transcriptional level, and GAS elements in the CD40 promoter are required for IFN-beta-induced CD40 promoter activity. The critical role of signal transducers and activators of transcription-1alpha (STAT-1alpha) in this response was confirmed by utilizing primary microglia from STAT-1alpha deficient mice. IFN-beta induces suppressor of cytokine signaling-1 (SOCS-1) gene expression, which inhibits cytokine signaling by inhibiting activation of STAT proteins. The ectopic expression of SOCS-1 abrogates IFN-beta-mediated STAT-1alpha activation and inhibits IFN-beta-induced CD40 expression. IFN-beta-induced recruitment of STAT-1alpha and RNA Pol II and permissive histone modifications on the CD40 promoter are also inhibited by SOCS-1 overexpression. These novel results indicate that IFN-beta-induced SOCS-1 plays an important role in the negative regulation of IFN-beta-induced CD40 gene expression.
16525037 A selective small molecule IkappaB Kinase beta inhibitor blocks nuclear factor kappaB-medi 2006 Jun IkappaB kinase (IKK) beta is essential for inflammatory cytokine-induced activation of nuclear factor kappaB (NF-kappaB). NF-kappaB plays a pivotal role in the function of major cell types that contribute to the pathophysiological process of rheumatoid arthritis (RA). Here, we report the mechanism and the effect of the IKKbeta inhibitor N-(6-chloro-7-methoxy-9H-beta-carbolin-8-yl)-2-methylnicotinamide (ML120B), a beta-carboline derivative, on NF-kappaB signaling and gene activation in RA-relevant cell systems. ML120B is a potent, selective, reversible, and ATP-competitive inhibitor of IKKbeta with an IC50 of 60 nM when evaluated in an IkappaBalpha kinase complex assay. ML120B does not inhibit other IKK isoforms or a panel of other kinases. ML120B concentration-dependently inhibits tumor necrosis factor alpha (TNFalpha)-stimulated NF-kappaB signaling via inhibition of IkappaBalpha phosphorylation, degradation, and NF-kappaB translocation into the nucleus. For the first time, we have demonstrated that in human fibroblast-like synoviocytes, TNFalpha- or interleukin (IL)-1beta-induced monocyte chemoattractant protein-1 regulated on activation, normal T cell expressed and secreted and production is IKKbeta-dependent. In addition, for the first time, we have demonstrated that lipopolysaccharide- or peptidoglycan-induced cytokine production in human cord blood-derived mast cells is IKKbeta-dependent. In addition, in human chondrocytes, ML120B inhibited IL-1beta-induced matrix metalloproteinase production with an IC50 of approximately 1 microM. ML120B also blocked IL-1beta-induced prostaglandin E2 production. In summary, ML120B blocked numerous NF-kappaB-regulated cell responses that are involved in inflammation and destructive processes in the RA joint. Our findings support the evaluation of IKKbeta inhibitors as anti-inflammatory agents for the treatment of RA.
16418778 Human osteoblast precursors produce extracellular adenosine, which modulates their secreti 2006 Feb We showed that human osteoprogenitor cells produced adenosine and expressed ecto-5'-nucleotidase and all four adenosine receptor subtypes. Adenosine stimulated IL-6 but inhibited osteoprotegerin secretion, suggesting that adenosine is a newly described regulator of progenitor cell function. INTRODUCTION: Maintaining skeletal homeostasis relies on there being a balance between bone formation and resorption; an imbalance between these processes can lead to diseases such as osteoporosis and rheumatoid arthritis. Recent reports showed that locally produced ATP, acting through P2 receptors, has pronounced effects on bone formation. However, ATP can be enzymatically cleaved to adenosine that has little or no activity at P2 receptors but mediates its action through the P1 family of receptors. We studied whether adenosine may also have an important role in controlling bone cell differentiation and function. MATERIALS AND METHODS: Extracellular adenosine levels were analyzed by high-performance liquid chromatography in HCC1 and bone marrow stromal (BMS) cells. Ecto-5'-nucleotidase (CD73) expression and activity was determined by RT-PCR, immunocytochemistry, and the cleavage of etheno-AMP to ethenoadenosine. Adenosine receptor expression and activity were determined by RT-PCR and cAMP measurements. The effects of adenosine receptor agonists on IL-6, osteoprotegerin (OPG), and RANKL expression were determined by ELISA and QRT-PCR. RESULTS: HCC1 and BMS cells produce adenosine and express CD73 and all four adenosine receptor subtypes. The A2b receptor was shown to be functionally dominant in HCC1 cells, as determined by cAMP production and in its stimulation of IL-6 secretion. Adenosine receptor agonism also inhibited OPG secretion and OPG but not RANKL mRNA expression. CONCLUSIONS: Our findings show that HCC1 and primary BMS cells produce adenosine, express CD73 and all four adenosine receptor subtypes. In HCC1 cells, adenosine has a potent stimulatory action on IL-6 secretion but an inhibitory action on OPG expression. These data show for the first time that adenosine may be an important regulator of progenitor cell differentiation and hence an important local contributor to the regulation of bone formation and resorption.
16339569 Differential regulation of osteoblast activity by Th cell subsets mediated by parathyroid 2005 Dec 15 Bone loss is a typical pathological feature of chronic inflammatory bone diseases including rheumatoid arthritis, in which CD4 effector T cells play critical roles. We found that activated mouse Th2 and not Th1 cells produced the parathyroid hormone (PTH). Unlike in the parathyroid cells, PTH expression in Th2 cells was not regulated by the fluctuation of calcium level, but rather it required the full activation of the T cells. Although PTH was expressed in immature Th2 cells, and its receptor was transiently expressed during Th1 and Th2 cell differentiation, PTH did not significantly affect the outcome of the differentiation. In primary osteoblasts cultured in Th2 cell condition medium, the alkaline phosphatase (ALP) activity was maintained at a basal level. However, antagonizing PTH in the condition medium resulted in a significant reduction of the ALP activity. These results demonstrated an important role of the Th2 cell-derived PTH in maintaining the bone-forming activity of the osteoblasts under inflammatory conditions. In osteoblasts cultured in the Th1 cell condition medium, the ALP activity was significantly suppressed. Neutralizing IFN-gamma alleviated the suppression. Conversely, treatment of osteoblasts with IFN-gamma suppressed the ALP activity. Unlike ALP, expression of the major bone matrix proteins by the osteoblasts was only minimally affected by either Th1 or Th2 cytokine environment. In addition, the Th2 cytokine environment also regulated to expression of receptor activator of NF-kappaB ligand and osteoprotegerin through both PTH-dependent and -independent mechanisms. Our study therefore identified new regulatory events in bone remodeling under inflammatory conditions.
15956351 TRAP220 is modulated by the antineoplastic agent 6-Mercaptopurine, and mediates the activa 2005 Jun The NR4A1-3 (Nur77, NURR1 and NOR-1) subfamily of nuclear hormone receptors (NRs) has been implicated in Parkinson's disease, schizophrenia, manic depression, atherogenesis, Alzheimer's disease, rheumatoid arthritis, cancer and apoptosis. This has driven investigations into the mechanism of action, and the identification of small molecule regulators, that may provide the platform for pharmaceutical and therapeutic exploitation. Recently, we found that the purine antimetabolite 6-Mercaptopurine (6-MP), which is widely used as an anti-neoplastic and anti-inflammatory drug, modulated the NR4A1-3 subfamily. Interestingly, the agonist-mediated activation did not involve modulation of primary coactivators' (e.g. p300 and SRC-2/GRIP-1) activity and/or recruitment. However, the role of the subsequently recruited coactivators, for example CARM-1 and TRAP220, in 6-MP-mediated activation of the NR4A1-3 subfamily remains obscure. In this study we demonstrate that 6-MP modulates the activity of the coactivator TRAP220 in a dose-dependent manner. Moreover, we demonstrate that TRAP220 potentiates NOR-1-mediated transactivation, and interacts with the NR4A1-3 subgroup in an AF-1-dependent manner in a cellular context. The region of TRAP220 that mediated 6-MP activation and NR4A interaction was delimited to amino acids 1-800, and operates independently of the critical PKC and PKA phosphorylation sites. Interestingly, TRAP220 expression does not increase the relative induction by 6-MP, however the absolute level of NOR-1-mediated trans-activation is increased. This study demonstrates that 6-MP modulates the activity of the NR4A subgroup, and the coactivator TRAP220.
17125837 A novel domain antibody rationally designed against TNF-alpha using variable region of hum 2007 Mar Neutralizing of TNF-alpha has been proved effective in treatment of some autoimmune diseases, e.g. rheumatoid arthritis and Crohn's disease. Low molecular weight synthetic peptides can mimic the binding sites of TNF-alpha receptors and block the activity of TNF-alpha. In order to stabilize the conformation, increase the affinity and bioactivity, in this study, heavy chain variable region of human antibody was used as a scaffold to simultaneously display three peptides, which were designed on the interaction between TNF-alpha and it's neutralizing monoclonal antibody. On the basis of the structural character and physical-chemical property of the families of seven kinds of heavy chain variable regions (VH) in human antibodies, the fifth type of VH was screened as scaffold to display the antagonist peptide. Based on the computer-guided molecular design method, a novel domain antibody against TNF-alpha (named as ATD5) was designed as TNF-alpha antagonist. The theoretical study showed that ATD5 was more stable than displayed antagonist peptide. The binding activity with TNF-alpha was higher than free peptides. After expression and purification in Escherichia coli, ATD5 could bind directly with TNF-alpha and inhibit the binding of TNF-alpha to its two receptors, TNFR1 and TNFR2. ATD5 could also reduce the TNF-alpha-mediated cytotoxicity and inhibit TNF-alpha-mediated caspase activation on L929 cells in a dose dependent manner. The activity of ATD5 was significantly stronger than three peptides displayed by ATD5. This study provides a novel strategy for the development of new TNF-alpha inhibitors. This study demonstrates that it is possible to screen potential antagonists of TNF-alpha using in vitro analysis systems in combination with the computer-aided modeling method.
17024318 Plasma homocysteine status in patients with ankylosing spondylitis. 2007 May Homocysteine (Hcy), a sulfur-containing amino acid, is eliminated through B vitamins-dependent pathways. Hyperhomocysteinemia has been found to be an independent risk factor for atherosclerotic cardiovascular, cerebrovascular, and peripheral vascular diseases. Recently, psoriasis, lupus, and rheumatoid arthritis were reported to be associated with hyperhomocysteinemia. This study was aimed to evaluate the changes of plasma Hcy level before and after sulfasalazine and MTX therapy in patients with ankylosing spondylitis (AS). One hundred and two patients with AS and ten normal controls were enrolled in the cross-sectional case-control study. Fasting plasma Hcy levels were determined by ELISA kits (IMX, Abbott). Hcy levels were compared to their Bath AS disease activity index (BASDAI) and the usage of sulfasalazine and/or MTX. Active disease was defined by BASDAI as more than 3 in a 10-cm scale with ESR >20 mm/h. For those patients with plasma Hcy >or=15 micromol/l, a perspective trial of daily supplement of vitamin B-12 0.5 mg, B-6 50 mg, and folic acid 5 mg for 2 weeks were also tested for the efficacy. Plasma Hcy level increased significantly in AS patients under sulfasalazine (10.4+/-3.8 micromol/l, p<0.05), MTX (11.9+/-4.7, p<0.05) and sulfasalazine/MTX combination treatment (11.2+/-2.6, p<0.05) compared with normal controls (8.6+/-1.2 micromol/l) and AS patients without DMARD(9.4+/- 2.6 micromol/l). No correlation between disease activity and plasma Hcy level was found. Daily supplement of vitamin B-12 0.5 mg, B-6 50 mg, and folic acid 5 mg can lower Hcy level in 2 weeks (32.3+/-24.0 vs 15.6+/-11.1 micromol/l, p=0.007). Plasma homocysteine level did significantly increase in AS patients under sulfasalazine or MTX treatment. B-vitamins should be considered as a routine supplementation for patients who underwent sulfasalazine and/or MTX treatment. Further longitudinal studies are required to confirm the conclusions.
16271309 Soluble interleukin-2 receptor as a marker for progression of coronary artery calcificatio 2006 INTRODUCTION: Soluble interleukin-2 receptor (sIL2r), a marker of T cell activation, is elevated in inflammatory processes, such as rheumatoid arthritis, hepatitis and neoplasm. We explored a potential association between plasma sIL2r levels and progression of coronary artery calcification (CAC), a marker for subclinical atherosclerosis, in a prospectively followed cohort of type 1 diabetic and non-diabetic subjects, aged 20-59 years, with no history of coronary artery disease. MATERIALS AND METHODS: CAC progression was assessed by electron beam tomography over 2.6 years (range 1.6-3.2). Plasma sIL2r levels were measured in a nested case-control substudy of 98 subjects (67 diabetic, 31 non-diabetic) with and 173 subjects (84 diabetic, 89 non-diabetic) without significant CAC progression. Log-transformed sIL2r levels were analyzed by conditional logistic regression to compare subjects with and without significant CAC progression. RESULTS: SIL2r was a significant predictor for CAC progression after adjusting for presence of baseline CAC, age, gender, diabetes status, baseline calcium volume score and adiponectin (OR 1.99, 95% CI 1.09-3.61, p = 0.02 for a doubling of sIL2r level). Addition of BMI, LDL, HDL, hypertension, smoking status, HbA1c, CRP, fibrinogen, homocysteine and PAI-1 to regression models weakened but did not remove sIL2r as a predictor of CAC progression. There was no indication that this effect was different by diabetes status (p = 0.6 for diabetes-sIL2r interaction). DISCUSSION: Elevated plasma sIL2r is associated with CAC progression independent of traditional coronary artery disease risk factors in type 1 diabetic and non-diabetic young adults. SIL2r should be considered as a novel marker of inflammation leading to coronary artery disease.
16223958 Mefenamic acid shows neuroprotective effects and improves cognitive impairment in in vitro 2006 Jan Nonsteroidal anti-inflammatory drugs (NSAIDs) exert anti-inflammatory, analgesic, and antipyretic activities and suppress prostaglandin synthesis by inhibiting cyclooxygenase, an enzyme that catalyzes the formation of prostaglandin precursors from arachidonic acid. Epidemiological observations indicate that the long-term treatment of patients suffering from rheumatoid arthritis with NSAIDs results in reduced risk and delayed onset of Alzheimer's disease. In this study, we investigated the therapeutic potential for Alzheimer's disease of mefenamic acid, a commonly used NSAID that is a cyclooxygenase-1 and 2 inhibitor with only moderate anti-inflammatory properties. We found that mefenamic acid attenuates the neurotoxicities induced by amyloid beta peptide (Abeta)(1-42) treatment and the expression of a Swedish double mutation (KM595/596NL) of amyloid precursor protein (Swe-APP) or the C-terminal fragments of APP (APP-CTs) in neuronal cells. We also show that mefenamic acid decreases the production of the free radical nitric oxide and reduces cytochrome c release from mitochondria induced by Abeta(1-42), Swe-APP, or APP-CTs in neuronal cells. In addition, mefenamic acid up-regulates expression of the antiapoptotic protein Bcl-X(L). Moreover, our study demonstrates for the first time that mefenamic acid improves learning and memory impairment in an Abeta(1-42)-infused Alzheimer's disease rat model. Taking these in vitro and in vivo results together, our study suggests that mefenamic acid could be used as a therapeutic agent in Alzheimer's disease.
16207182 Twelve-year clinico-therapeutic experience in pemphigus: a retrospective study of 54 cases 2005 Oct BACKGROUND: Pemphigus, a common immunobullous disease of skin and mucous membranes affecting both sexes of all ages, was almost fatal before the advent of corticosteroids. Better strategies to avoid their side-effects and recent introduction of adjuvant therapy has further improved its prognosis. As the treatment remains need-based and patient-specific, different regimens and strategies have evolved, each with its own merits and demerits. This retrospective hospital-based study was carried out to understand the clinico-therapeutic aspects of pemphigus in our clinic. METHODS: Medical records of all new patients admitted to our hospital with the diagnosis of pemphigus from 1990 to 2002 were analyzed. The diagnosis was mainly clinical and confirmed by positive Tzanck's test and histopathology. All patients were assessed clinically on a severity score of 1+ to 4+. These patients had received treatment with dexamethasone-cyclophosphamide pulse (DCP) therapy, oral mini-pulse (OMP) with betamethasone, or intramuscular triamcinolone acetonide alone or with azathioprine, dapsone or cyclophosphamide. They were followed up for clinical remission and side-effects of therapy. RESULTS: There were a total of 54 new patients comprising 53.7% females and 46.3% males, and 12.9% of these were < 18 years of age. Pemphigus vulgaris was the commonest clinical type seen in 81.48% and mucosal involvement was seen in 63.63% of cases. The severity of mucosal lesions was not proportionate to that of cutaneous lesions. Associated diseases seen were seropositive rheumatoid arthritis, hypertension, diabetes mellitus and hyperthyroidism in one case each. Dexamethasone-cyclophosphamide pulse therapy was given to 75% of the pemphigus vulgaris patients while those having less severe disease were treated with other regimens. In general, clinical remission was seen after 2-16 (mean 6.5) DCP doses. Two patients have been in complete remission for the last 5 and 7 years of completion of DCP therapy, respectively. Addition of other adjuvants to corticosteroids was also helpful. However, azathioprine 50 mg/day was not as effective as cyclophosphamide 50 mg/day. Menstrual irregularities, amenorrhoea, azoospermia, rise in blood pressure and glycosuria were the major side-effects seen during DCP pulse therapy. Drop out rate was unacceptably high with all modes of treatment, although with DCP therapy it appears to be partly owing to early disease control. There was no mortality in this series. CONCLUSIONS: Pemphigus vulgaris is the commonest clinical type. Mucosal surfaces other than the oral cavity are uncommonly involved, it may herald the onset of disease and takes longer to heal. Dexamethasone-cyclophosphamide pulse therapy seems to have a definite advantage over treatment with steroids alone, especially in terms of better control of disease activity, near absence of steroid side-effects and significantly reduced hospital stay. However, ways and means to reduce gonadal toxicity of adjuvants need to be explored as DCP therapy is likely to stay as a treatment of choice.
16194440 [Evaluation of the survival of the Walter-Motorlet TKA: long-term outcomes]. 2005 PURPOSE OF THE STUDY: The aim of the study was: 1. statistical evaluation of the survival of the first Czech TKA of Walter-Motorlet type, 2. comparison of the outcomes of different types of tibial components and finding out of the difference, if any, in the survival of all-poly and metal-backed components. MATERIAL: The authors evaluated a group of patients treated by the Walter-Motorlet TKA in the period between September 1984 and December 1989. The cohort comprised 170 patients with 211 knees. Of this group, available to follow-up were 185 TKA in 148 patients on average 17.5 years after the operation (range, 15.0-20.1 years). One female patient who died of pulmonary embolism was not included in the study. The final cohort thus comprised 184 TKA in 147 patients. METHOD: The evaluation of the general outcomes was based on the method of the cumulative survival curve after Kaplan-Meier in dependence on the type of the implant its components and basic diagnosis. In addition, the authors carried out a comparison of different types of tibial components. OUTCOMES: After 20 years the curve shows 76% as the cumulative number of the survived implants. Eighteen TKA failed due to aseptic loosening and 12 TKA for infection. The comparison of survival curves in rheumatoid arthritis (RA) and osteoarthritis (OA) in case of the femoral components is in absolute terms slightly better in RA patients, however statistically this difference is insignificant (p = 0.34). Similar result was achieved in the tibial component, i. e. slightly better in RA patients, however only until the interval of 18 years after the surgery. After this interval the curve shows identical course in both diseases (p = 0.20). The comparison of individual all-poly tibial components revealed slightly better results in total plateau replacements (p = 0.13), the comparison of metal and total all-poly tibial components is slightly better in the metal-backed components (p = 0.07). However, the differences found out in all these cases are not statistically significant, either, and the outcomes of both types of components may be considered identical. DISCUSSION: Evaluation of the cohort at the interval of up to 20 years after the surgery only by means of usual health status documentation is highly demanding. The cumulative number of the survived implants evaluated by the Kaplan-Meier method after 20 years was 76%. There is no study following the cumulative survival of the TKA exceeding ten years in the Czech literature and these studies are not very frequent in other countries, either. Comparison of the outcomes of our study is difficult as the criteria used in different published studies are not uniform. Slightly more favourable results in RA patients may be ascribed to the fact that their demands for physical activity is not so high. Comparable outcomes of the all-poly and metal backed tibial components are rather surprising and their confirmation would require a more detailed examination in a randomized prospective study. CONCLUSION: Based on the comparison with similar articles published abroad, 76% as the outcome of the cumulative survival of the first type of the Walter-Motorlet TKA after more than 17 years may be considered satisfactory. The study has confirmed a good long-term survival of all-poly tibial components comparable with metal-backed components. It has indicated slightly better results in the survival of TKA in patients with RA as compared to those with OA, although the difference is not statistically significant. Evaluation of a greater cohort of patients at a longer interval after surgery would be considerably facilitated by the existence of a central TKA register.
15680249 NSAIDs increase GM-CSF release by human synoviocytes: comparison with nitric oxide-donatin 2005 Jan 31 Non-steroidal anti-inflammatory drugs (NSAIDs) are used to treat the condition of rheumatoid arthritis, where levels of prostaglandin E2 (PGE2) and granulocyte macrophage-colony stimulating factor (GM-CSF) are elevated in the synovial fluid. NO-NSAIDs are a new class of cyclooxygenase (COX)-inhibitors developed by coupling a nitric oxide (NO)-donating moiety to conventional NSAIDs. We show that, in cytokine-treated synoviocytes (from non-rheumatic patients), NO-naproxen and NO-flurbiprofen like their parent compounds concentration-dependently reduce the levels of PGE2 (an index of COX-2 activity), with a corresponding rise in the release of GM-CSF. Unlike acetylsalicylic acid (ASA), NO-ASA reduces the levels of PGE2, without increasing GM-CSF release, although cell viability is reduced at the highest concentration (1 mM). The effects of NSAIDs and NO-NSAIDs on GM-CSF release were attributable to the PGE2 mediated cyclic (c) AMP pathway because PGE2 reversed the effects of COX blockade. Second, phosphodiesterase inhibitors 3-isobutyl-1-methylxanthine (IBMX) and Ro-201724 (both of which elevate cAMP levels) decreased GM-CSF release, in the presence of PGE2. Finally, neither sodium nitroprusside nor zaprinast (both of which elevate cGMP levels) affected GM-CSF or PGE2 release. Our findings demonstrate that GM-CSF is regulated by NSAIDs and NO-NSAIDs via inhibition of COX and appears to be mediated via the cAMP pathway. NO-ASA is the exception, because it does not increase GM-CSF release, although at millimolar concentrations cell viability is reduced.