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ID PMID Title PublicationDate abstract
12154041 Gene expression microarray analysis reveals YKL-40 to be a potential serum marker for mali 2002 Aug 1 We have identified a potential serum marker for glioblastoma multiforme (GBM) using microarray analysis from samples of GBM. We compared the gene expression profile of 19 gliomas to pooled normal brain by competitive hybridization of RNA from each tumor sample to a pooled sample of RNA isolated from normal brain tissue using the Incyte 10,000 gene expression array. The most differentially expressed gene in this analysis encodes a secreted glycoprotein and is referred to as YKL-40. YKL-40 mRNA was detected in the GBM samples with a range of 3- to 62-fold elevation over normal brain. It has been reported previously that this protein is expressed in pathologic conditions of extracellular matrix degradation and angiogenesis, such as rheumatoid arthritis, severe osteoarthritis, hepatic fibrosis, primary colorectal cancer, and metastatic breast cancer. These data suggest YKL-40 may be involved in extracellular matrix degradation and/or angiogenesis. Western blot analysis of glioma samples for YKL-40 protein levels revealed substantial elevation in approximately 65% of GBMs and undetectable levels in lower-grade gliomas (grade II and III) or normal brain tissue. We performed ELISA analysis on serum samples of glioma patients to determine whether this protein would correlate with the presence of tumor and tumor grade or burden. YKL-40 serum levels were substantially elevated in many of the GBM patients. Statistical analysis of these data indicates that in patients with glioma, serum YKL-40 levels correlate with tumor grade and potentially tumor burden in GBM.
15572357 The Met-196 -> Arg variation of human tumor necrosis factor receptor 2 (TNFR2) affects TNF 2005 Feb 18 Tumor necrosis factor-alpha (TNF-alpha)-induced signaling is pivotally involved in the pathogenesis of chronic inflammatory diseases. A polymorphism in the TNF receptor 2 (TNFR2) gene resulting in a juxtamembrane inversion from methionine (TNFR2(196MET)) to arginine (TNFR2(196ARG)) has been genetically associated with an increased risk for systemic lupus erythematosus and familial rheumatoid arthritis. Albeit the mutation does not affect the TNF binding kinetics of TNFR2, the present study provides evidence that the mutation results in a significantly lower capability to induce TNFR2-mediated NF-kappaB activation. Pretriggering of TNFR2 with a receptor-specific mutein leads to an enhancement of TNFR1-induced apoptosis, which is further increased in cells carrying the TNFR2(196ARG) variant. A diminished induction of NF-kappaB-dependent target genes conveying either anti-apoptotic or pro-inflammatory functions, such as cIAP1, TRAF1, IL-6, or IL-8 is observed. The mutated form TNFR2(196ARG) shows a reduction of inducible TRAF2 recruitment upon TNF-alpha stimulation. The findings suggest a common molecular mechanism for the involvement of the TNFR2(196ARG) variant in the etiopathogenesis of different chronic inflammatory disorders.
15538942 Tumor necrosis factor-alpha (TNF-alpha) promotes cell survival during spermatogenesis, and 2004 Nov OBJECTIVE: Tumor necrosis factor-alpha (TNF-alpha) has been shown to inhibit germ cell death in human seminiferous epithelium. In the present study, we wanted to explore the effects of TNF-alpha in the rat seminiferous epithelium and to study molecular mechanisms of germ cell apoptosis. Furthermore, the effects of infliximab were studied. Infliximab is a TNF-alpha antagonist used in autoimmune disorders, such as rheumatoid arthritis and Crohn's disease. METHODS: Rat seminiferous tubule segments were cultured in the presence and absence of TNF-alpha, infliximab and SN50, a NF-kappa B inhibitor. TUNEL-staining and cleaved caspase-3 immunohistochemistry combined with squash preparations of rat seminiferous tubule segments were used to evaluate the number of apoptotic cells. Western blot analyses were performed on cultured seminiferous tubule segments for Bcl-2 family proteins (Bax, Bad, Bcl-w, Bcl-xL) and fas ligand. RESULTS: TNF-alpha promotes cell survival in the rat seminiferous epithelium, and this prosurvival effect can be blocked by infliximab, a TNF-alpha antagonist. Bcl-xL was found to be upregulated in mitochondrial membranes by TNF-alpha, and this upregulation was inhibited by infliximab. Inhibition of NF-kappa B translocation to the nucleus prevented the prosurvival effect of TNF-alpha on seminiferous epithelium. CONCLUSIONS: The present study demonstrates that TNF-alpha promotes cell survival in the rat seminiferous epithelium, and this effect can be blocked by infliximab. This is the first study to show the effects of infliximab in the testis. The prosurvival effect of TNF-alpha might be at least partly mediated by modulating the expression and subcellular localization of Bcl-2 family proteins.
14998631 Minocycline inhibits caspase activation and reactivation, increases the ratio of XIAP to s 2004 Mar 3 OBJECTIVES: This study is aimed at investigating the novel use of minocycline for cardiac protection during ischemia/reperfusion (I/R) injury, as well as its mechanism of action. BACKGROUND: Minocycline is a tetracycline with anti-inflammatory properties, which is used clinically for the treatment of diseases such as urethritis and rheumatoid arthritis. Experimentally, minocycline has also been shown to be neuroprotective in animal models of cerebral ischemia and to delay progression and improve survival in mouse models of neurodegenerative diseases. METHODS: We studied 62 rat intact hearts exposed to I/R and cell cultures of neonatal and adult rat ventricular myocytes. RESULTS: Minocycline significantly reduced necrotic and apoptotic cell death, both in neonatal and adult myocytes, not only when given prior to hypoxia (p < 0.001), but also at reoxygenation (p < 0.05). Moreover, in the intact heart exposed to I/R, in vivo treatment with minocycline promoted hemodynamic recovery (p < 0.001) and cell survival, with reduction of infarct size (p < 0.001), cardiac release of creatine phosphokinase (p < 0.001), and apoptotic cell death (p < 0.001). In regard to its antiapoptotic mechanism of action, minocycline significantly reduced the expression level of initiator caspases, increased the ratio of XIAP to Smac/DIABLO at both the messenger RNA and protein level, and prevented mitochondrial release of cytochrome c and Smac/DIABLO (all, p < 0.05). These synergistic actions dramatically prevent the post-ischemic induction of caspase activity associated with cardiac I/R injury. CONCLUSIONS: Because of its safety record and multiple novel mechanisms of action, minocycline may be a valuable cardioprotective agent to ameliorate cardiac dysfunction and cell loss associated with I/R injury.
14987986 Synthesis and biological evaluation of neutrophilic inflammation inhibitors. 2004 Mar In several non-infectious human diseases, such as ulcerous colitis, rheumatoid arthritis, chronic obstructive pulmonary disease (COPD), the extravasal recruitment of neutrophils plays a crucial role in the development of tissue damage, which, when persistent, can lead to the irreversible organ dysfunction. The neutrophil activation is controlled by a number of intracellular pathways, particularly by a cAMP-dependent protein kinase A (PKA) which also acts on phosphodiesterase IV (PDE4) gene stimulating the synthesis of this enzyme, able to transform cAMP to inactive AMP. PDE4 inhibitors enhance intracellular cAMP and decrease inflammatory cell activation. Several 3-cyclopentyloxy-4-methoxybenzaldehyde and 3-cyclopentyloxy-4-methoxybenzoic acid derivatives were synthesized and studied by us to evaluate their ability to inhibit the superoxide anion production in human neutrophils. These compounds were found able to inhibit the neutrophil activation and some of them increased the cAMP level on tumor necrosis factor-alpha-stimulated neutrophils. Moreover, they also inhibited selectively the human PDE4 enzyme, although they are less potent than the reference compound Rolipram. We report here synthesis, biological studies and some SAR considerations concerning the above mentioned compounds.
14633791 Hematopoietic cell transplantation for benign hematological disorders and solid tumors. 2003 Allogeneic hematopoietic cell transplantation (HCT) has been successfully used as replacement therapy for patients with aplastic anemia and hemoglobinopathies. Both autologous and allogeneic HCT following high-dose chemotherapy can correct manifestations of autoimmune diseases. The impressive allogeneic graft-versus-tumor effects seen in patients given HCT for hematological malignancies have stimulated trials of allogeneic immunotherapy in patients with otherwise refractory metastatic solid tumors. This session will update the status of HCT in the treatment of benign hematological diseases and solid tumors. In Section I, Dr. Rainer Storb reviews the development of nonmyeloablative conditioning for patients with severe aplastic anemia who have HLA-matched family members. He also describes the results in patients with aplastic anemia given HCT from unrelated donors after failure of responding to immunosuppressive therapy. The importance of leuko-poor and in vitro irradiated blood product transfusions for avoiding graft rejection will be discussed. In Section II, Dr. Guido Lucarelli reviews the status of marrow transplantation for thalassemia major and updates results obtained in children with class I and class II severity of thalassemia. He also describes results of new protocols for class III patients and efforts to extend HCT to thalassemic patients without HLA-matched family members. In Section III, Dr. Peter McSweeney reviews the current status of HCT for severe autoimmune diseases. He summarizes the results of autologous HCT for systemic sclerosis, multiple sclerosis, rheumatoid arthritis, and systemic lupus erythematosus, and reviews the status of planned Phase III studies for autologous HCT for these diseases in North America and Europe. He also discusses a possible role of allogeneic HCT in the treatment of these diseases. In Section IV, Dr. Richard Childs discusses the development and application of nonmyeloablative HCT as allogeneic immunotherapy for treatment-refractory solid tumors. He reviews the results of pilot clinical trials demonstrating graft-versus-solid tumor effects in a variety of metastatic cancers and describes efforts to characterize the immune cell populations mediating these effects, as well as newer methods to target the donor immune system to the tumor.
12704784 IL-13 regulates vascular cell adhesion molecule-1 expression in human osteoblasts. 2003 May 15 Activated T cells (Act T) produce multiple cytokines that affect osteoblast function as well as osteoclastogenesis. One of these cytokines, IL-13, is a multifunctional cytokine elaborated by Act T that regulates vascular cellular adhesion molecule (VCAM)-1 expression in endothelial cells. VCAM-1 has also been implicated in osteoclast formation by myeloma cells. We therefore studied whether IL-13 regulates VCAM-1 in human osteoblastic cells since these cells express RANKL, the major osteoclastogenic factor and osteoclast precursors are found adjacent to osteoblasts. Human T cells were activated in the absence or presence of Cyclosporin A (CsA), an inhibitor of the production of most activated T cell cytokines. Conditioned media were assayed for IL-13 by ELISA. Act T produced IL-13 and, unlike other T cell cytokines, this was elevated 3-fold by CsA. Exposure of human osteoblasts (hOB) to doses of recombinant human IL-13 (rhIL-13, 0-10 ng/ml) resulted in an increase of VCAM-1 mRNA (up to 5-fold) within 4 h with a maximum stimulation at 1 ng/ml. CsA had no effect on basal hOB VCAM-1 mRNA expression. Examination of VCAM-1 on the cell surface of hOB, by immunocytochemistry, revealed increasing levels of surface expression of the protein within 16 h after stimulation with doses of rhIL-13 (0.1-10 ng/ml) which were reflective of the mRNAs. IL-6 production was also stimulated in a dose dependent manner with a maximum of 2.5-fold with 1 ng/ml rhIL-13 within 16 h. Since both VCAM-1 and IL-6 showed similar responses to IL-13, IL-6 was examined for its ability to induce VCAM-1. Immunocytochemistry demonstrated no effect of IL-6 on VCAM-1 expression. These data demonstrate that during pathological processes associated with T cell activation, such as rheumatoid arthritis or possibly post-menopausal osteoporosis, T cells may play a pivotal role in osteoclast precursor adhesion to osteoblasts as a first step prior to RANKL signaling.
12472376 The Ca2+-activated K+ channel of intermediate conductance:a possible target for immune sup 2002 Dec The intermediate conductance Ca2+-activated K+ (IK) channel is distinguished from the functionally related Ca2+-activated K+ channels of smaller and larger unitary conductance by its molecular structure, pharmacology, tissue distribution and physiology. Like many K+ channels, IK is an assembly of four identical subunits each spanning the membrane six times and each contributing equally to the K+ selectivity pore positioned centrally in the complex. The IK channel gains its high sensitivity to intracellular Ca2+ from tightly bound calmodulin, and its activity is independent of the membrane potential. Several toxins including charybdotoxin and the more selective mutant, Glu32-charybdotoxin, maurotoxin and stichodactyla toxin potently block IK channels. Among blockers of the IK channel are also several small organic molecules including the antimycotic clotrimazole and the close analogues TRAM-34 and ICA-17043, as well as the antihypertensive, nitrendipine. The IK channel is distributed in peripheral tissues, including secretory epithelia and blood cells, but it appears absent from neuronal and muscle tissue. An important physiological role of the IK channel is to help maintain large electrical gradients for the sustained transport of ions such as Ca2+ influx that controls T lymphocyte (T cell) proliferation. In this review, special attention is given to an analysis of the use of IK blockers as potential immunosuppressants for the treatment of autoimmune disorders such as rheumatoid arthritis, inflammatory bowel disease and multiple sclerosis.
12456318 Regulation of plasminogen receptors. 2003 Jan 1 Many eukaryotic and prokaryotic cells bind plasminogen in a specific and saturable manner. When plasminogen is bound to cell-surface proteins with C-terminal lysines via its lysine binding sites, its activation to plasmin is accelerated, and cell-bound plasmin is protected from inactivation by natural inhibitors. Plasmin mediates direct or indirect degradation of the extracellular matrix, and bound plasmin is used by cells to facilitate migration through extracellular matrices. Since cell migration and tissue remodelling are the underpinnings of many physiological and pathological responses, the modulation of plasminogen receptors may serve as a primary regulatory mechanism for control of many cellular responses. Specific examples of cell types on which plasminogen receptors undergo modulation include: fibroblasts, where modulation may contribute to cartilage and bone destruction in rheumatoid arthritis; leukemic cells, where enhanced plasminogen binding may contribute to the heightened fibrinolytic state in the patients; other tumor cells, where up-regulation may support invasion and metastasis; bacteria, where enhanced plasminogen binding may facilitate tissue destruction and invasion; platelets, where up-regulation of plasminogen binding may play a role in regulating clot lysis; and adipocytes, where the modulation of plasminogen receptor expression may regulate cell differentiation and fat accumulation. Two pathways for modulation of plasminogen receptors have been characterized: A protease-dependent pathway can either up-regulate or down-regulate plasminogen binding to cells by changing the availability of plasminogen-binding proteins with C-terminal lysines. New receptors may be generated by trypsin-like proteases, including plasmin, which create new C-terminal lysines; other enzymes may expose existing membrane proteins by altering the cell surface; or receptor function may be lost by removal of C-terminal lysines. The basic carboxypeptidases of blood carboxypeptidase N and plasma carboxypeptidase B (TAFI) mediate such down-regulation. A non-protease dependent pathway for modulation of plasminogen receptors may be initiated by growth factors, chemokines or cytokines that alter the cell membrane and/or cytoskeleton architectures to expose plasminogen binding sites. Many examples of the modulation of plasminogen receptors have been demonstrated in vitro, and the development of knock-out mice may soon lead to incisive evaluations of the significance of the regulation of plasminogen receptors in vivo.
12220103 Characterization of CD3+ CD4- CD8- (double negative) T cells in patients with systemic lup 2002 Systemic lupus erythematosus (SLE) is characterized by B cell hyperactivity and the production of autoantibodies, some of which (antibodies to dsDNA) are thought to be pathogenic. T helper cells drive the production of autoantibodies and the aim of this study is to characterize phenotypically a subpopulation of T cells (the CD3+ CD4- CD8-, double negative (DN) T cells) previously identified as helping to enhance anti-DNA antibodies in patients with SLE. Data were obtained using FACS staining of DN T cells that had been purified from PBMCs by magnetic bead separation. The percentage of TCR alphabeta+ DN T cells was found to be significantly higher in patients with SLE as compared with controls (P = 0.02), although there was no significant increase in total percentage of DN T cells, which includes TCR gammadelta+ cells. Activation markers HLA-DR and CD69, the costimulatory molecule CD28 and CTLA-4 were all expressed on the surface of a higher percentage of DN T cells in patients with SLE than in patients with rheumatoid arthritis (RA) or healthy controls (HC). More DN T cells from patients with SLE were of CD45RA phenotype than was found in controls, while CD45RO-expressing cells were reduced. In addition, DN T cells from patients with SLE expressed significantly higher levels of HLA-DR (P = 0.006), CD28 (P = 0.05), CTLA4 (P = 0.03) and CD45RA (P = 0.05) on the cell surface than those from the CD4/8 population. Correlation of expression of the markers measured with various parameters of disease activity and severity showed that high levels of HLA-DR expression correlated with high circulating serum C3 (> 0.9 IU/ml), indicating that an activated phenotype is consistent with severe disease.
12114277 Antiproliferative-antiinflammatory effects of methotrexate and sex hormones on cultured di 2002 Jun Methotrexate (MTX) is believed to exert both antiproliferative and antiinflammatory effects in a dose-related manner in a majority of rheumatoid arthritis (RA) patients along with an abrupt flare of the disease after drug discontinuation. To investigate the antiproliferative and antiinflammatory actions of MTX and the combined action of sex hormones, we evaluated these effects in differentiated monocytic myeloid cells (THP-1) prestimulated with testosterone (T) or 17-beta estradiol (E2). The effects of MTX and T combined treatment (T/MTX) on THP-1 cells showed a significant inhibition of cell proliferation when compared with E2/MTX- treated cells or controls: 53% at 72 h versus E2-treated cells; 58% at 96 h versus E2-treated cells; and 41% versus controls, respectively. Bax and Fas CD95 expression was found increased in T-treated cells: 14% T at 48 h vs. E(2)-treated cells and controls; 45% T at 72 h versus E2-treated cells and controls; 97% at 96 h versus E2-treated cells and 37% versus controls for Bax: 33%, 41%, and 42% T versus E2-treated cells for Fas. Moreover, a significant decrease of IL-12 levels in T/MTX treated cells was found at any time when compared to E2-treated cells. In summary, the association of testosterone and MTX compared to MTX alone suggests possible synergistic actions. Therefore, the enhancing antiinflammatory effects exerted by androgens might represent a further explanation for the reduced frequency of inflammatory diseases in male subjects.
21735587 (64)Cu-Tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-MEDI-522. 2004 Integrins are a family of heterodimeric glycoproteins on cell surfaces that mediate diverse biological events involving cell–cell and cell–matrix interactions (1). Integrins consist of an α and a β subunit and are important for cell adhesion and signal transduction. The α(v)β(3) integrin is the most prominent receptor affecting tumor growth, tumor invasiveness, metastasis, tumor-induced angiogenesis, inflammation, osteoporosis, and rheumatoid arthritis (2-7). Expression of the α(v)β(3) integrin is strong on tumor cells and activated endothelial cells, whereas expression is weak on resting endothelial cells and most normal tissues. Antagonists of α(v)β(3) are being studied as antitumor and antiangiogenic agents, and the agonists of α(v)β(3) are being studied as angiogenic agents for coronary angiogenesis (6, 8, 9). A tripeptide sequence consisting of Arg-Gly-Asp (RGD) has been identified as a recognition motif used by extracellular matrix proteins (vitronectin, fibrinogen, laminin, and collagen) to bind to a variety of integrins, including α(v)β(3). Various radiolabeled antagonists have been introduced for imaging of tumors and tumor angiogenesis (10). Most cyclic RGD peptides are composed of five amino acids. Haubner et al. (11) reported that various cyclic RGD peptides exhibit selective inhibition of binding to α(v)β(3) (inhibition concentration (IC(50)), 7–40 nM) but not to integrins α(v)β(5) (IC(50), 600–4,000 nM) or α(IIb)β(3) (IC(50), 700–5,000 nM). Various radiolabeled cyclic RGD peptides have been found to have high accumulation in tumors in nude mice (12). In addition to RGD peptides, a humanized anti-human integrin α(v)β(3) monoclonal antibody (MEDI-522) was identified to be unique in that it recognizes either the human α(v) or β(3) subunit. MEDI-522 cross-reacts with integrin α(v)β(3) from rabbits, chickens, and hamsters but not with integrin α(v)β(3) from mice or rats (13). MEDI-522 is being evaluated as an antiangiogenic agent for cancer therapy (14-16). Cai et al. (17) reported the development of (64)Cu-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-MEDI-522 ((64)Cu-DOTA-MEDI-522) for positron emission tomography (PET) imaging of α(v)β(3) receptors in nude mice bearing tumors.
21595127 (68)Ga-Tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-Glu-[cyclo(Arg-Gly-Asp-D-Phe-L 2004 Integrins are a family of heterodimeric glycoproteins on cell surfaces that mediate diverse biological events involving cell–cell and cell–matrix interactions (1). Integrins consist of an α and a β subunit and are important for cell adhesion and signal transduction. The α(v)β(3) integrin is the most prominent receptor affecting tumor growth, tumor invasiveness, metastasis, tumor-induced angiogenesis, inflammation, osteoporosis, and rheumatoid arthritis (2-7). Expression of the α(v)β(3) integrin is strong on tumor cells and activated endothelial cells, whereas expression is weak on resting endothelial cells and most normal tissues. Antagonists of α(v)β(3) are being studied as antitumor and antiangiogenic agents, and the agonists of α(v)β(3) are being studied as angiogenic agents for coronary angiogenesis (6, 8, 9). Extracellular matrix proteins (vitronectin, fibrinogen, laminin, and collagen) contain a tripeptide sequence consisting of Arg-Gly-Asp (RGD), which binds to a variety of integrins, including α(v)β(3). Various radiolabeled antagonists have been introduced for imaging of tumors and tumor angiogenesis (10). Most cyclic RGD peptides are composed of five amino acids. Haubner et al. (11) reported that various cyclic RGD peptides exhibit selective inhibition of binding to α(v)β(3) (inhibition concentration (IC(50)), 7–40 nM) but not to integrins α(v)β(5) (IC(50), 600–4,000 nM) or α(IIb)β(3) (IC(50), 700–5,000 nM). Various radiolabeled cyclic RGD peptides have been found to have high accumulation in tumors in nude mice (12). Janssen et al. (13) reported the development of (111)In-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-Glu-[cyclo(Arg-Gly-Asp-D-Phe-Lys)](2) ((111)In-DOTA-E-[c(RGDfK)](2)) for single-photon emission computed tomography imaging α(v)β(3) receptors in nude mice bearing ovarian carcinoma tumors. Dijkgraaf et al. (14) also reported the evaluation of (68)Ga-DOTA-E-[c(RGDfK)](2) for positron emission tomography (PET) imaging α(v)β(3) receptors in tumor, which is the topic of this chapter.
15088884 Subantimicrobial dose doxycycline efficacy as a matrix metalloproteinase inhibitor in chro 2004 Mar BACKGROUND: Administration of subantimicrobial dose doxycycline (SDD) to chronic periodontitis (CP) patients has repeatedly been found to reduce mammalian collagenase and other matrix metalloproteinase (MMP) activity in gingival tissues and crevicular fluid, in association with clinical efficacy, without the emergence of antibiotic-resistant bacteria either orally or extra-orally. More recently, SDD adjunctive to repeated mechanical debridement resulted in dramatic clinical improvement in patients (>50% smokers) with generalized aggressive periodontitis. As an additional pharmacologic approach, non-steroidal anti-inflammatory drugs (NSAIDs) can reduce gingival inflammation and alveolar bone resorption, at least under experimental conditions. In the current study, we determined the effect of administering a combination (combination) of these two host-modulating drugs (SDD plus low-dose NSAID) to CP patients, on selected neutral proteinases in gingiva, enzymes believed to mediate periodontal breakdown. Earlier preliminary studies in humans with bullous pemphigoid, which is also associated with excessive levels of host-derived proteinases including MMPs, indicated improved clinical efficacy of combination therapy. METHODS: Nineteen CP patients, scheduled for mucoperiosteal flap surgery bilaterally in the maxillary arch, were randomly distributed into three experimental groups administered either 1) low-dose flurbiprofen (LDF) alone, 50 mg q.d.; 2) SDD (20 mg b.i.d.) alone; or 3) a combination of SDD plus LDF (combination). The gingival tissues were biopsied during surgery from right and left maxillary posterior sextants, before and after a 3-week regimen of medication, respectively. The tissues were then extracted, the extracts partially purified, then analyzed for the endogenous proteinase inhibitor, alpha1-PI, and its breakdown product, and for host-derived matrix metalloproteinases (i.e., collagenases, gelatinases) and neutrophil elastase activities. RESULTS: Short-term therapy with SDD alone produced a significant reduction and LDF alone produced no reduction in host-derived neutral proteinases. However, the combination therapy produced a statistically significant synergistic reduction of collagenase, gelatinase, and serpinolytic (alpha1-PI degrading) activities (69%, 69%, and 75% reductions, respectively) and a lesser reduction of the serine proteinase, elastase (46%). CONCLUSIONS: Consistent with previous studies on animal models of chronic destructive disease (e.g., rheumatoid arthritis), the SDD and NSAID combination therapy synergistically suppressed MMP and other neutral proteinases in the gingiva of CP patients. A mechanism, suggested by earlier animal studies, involves the NSAID, in the combination regimen, increasing the uptake of the tetracycline-based MMP inhibitor in the inflammatory lesion, thus synergistically enhancing the efficacy of this medication.
15470521 Apoptosis and necrosis increase antigenicity of proteins recognized by antinuclear antibod 2004 Jul OBJECTIVE: Present study addresses the issue whether apoptosis and necrosis increases the antigenicity of proteins recognized by antinuclear antibodies. MATERIAL AND METHODS: HEp-2 cells were cultured in standard conditions; apoptosis was induced by camptothecin and necrosis by mercuric chloride. Protein antigenicity of cell extracts was tested onto nitrocellulose membranes and probed with positive or negative sera for antinuclear antibodies by a luminescent-dot-ELISA system. RESULTS: Apoptotic changes in HEp-2 cells appeared by 24 hours of camptothecin exposure, meanwhile the necrotic features become visible earlier. Luminescence was significantly superior in ANA positive sera than in ANA negative controls. Antinuclear antibody sera recognized better the antigens from the apoptotic and necrotic cells than controls without chemical treatments. CONCLUSIONS: Apoptosis and necrosis increase the ANA binding by better availability of intracellular antigens, or by disclosing cryptic epitopes.
15971588 [Screening and characterization of DNA aptamers with hTNF-alpha binding and neutralizing a 2003 Nov Human tumor necrosis factor alpha (hTNF-alpha) is one of the most important inflammatory cytokines that acts as a mediator in inflammatory and immune response and plays a key role in host defense against infection. The over expression of hTNF-alpha is associated with serious consequences, such as shock, hypotension, thrombus, septicemia and even death. It has been implicated in many autoimmune and inflammatory diseases, such as rheumatoid arthritis, Crohn's disease, chronic heart failure and septic shock. Inhibiting the bio-activity of hTNF-alpha is one of the strategy for the treatment of these diseases. Compared with traditional recombinant protein drugs, small molecule drugs have many advantages, such as high affinity, low immunogenecity and low cost. Systematic evolution of ligands by exponential enrichment (SELEX) is a powerful method for the selection of oligonucleotides that bind with high affinity and specificity to target proteins. Such oligonucleotides are called aptamers, and are potential therapeutics for blocking the activity of pathologically relevant proteins. To obtain oligonucleotide aptamers specifically binding to TNF, a 40nt random DNA combinatorial library flanked by 31nt fixed sequences was chemically synthesized. The random library was amplified with PCR and subjected to selection by SELEX protocol against hTNFalpha. After incubation of the library with hTNFalpha, the mixture was blotted onto Immobilon-NC transfer membrane. The no-specific binding was washed away and the hTNFa binding aptamers were eluted and detached from the target protein. The eluted oligo nucleotides were amplified with PCR and served as the DNA library for the next round selection. After 12 rounds of such selection, the selected aptamers were cloned to pGEM-T vector. Positive clones were identified by restriction enzyme digestion and DNA sequencing. Oligo DNA were synthesized according to the sequence data and tested for their activities. Binding activity of the aptamers to hTNFalpha were detected by ELISA and dot blot with biotin-streptavidin-horseradish peroxidase system. Mouse L929 cells were used to test the anti-hTNFa activity of the DNA aptamers. The aptamers were incubated with hTNFalpha and added to the L929 cells. The results were read under microscope and with MTT staining. It was shown that these DNA aptamers bound to hTNFalpha with high affinity, and can inhibit the cytotoxicity of hTNFalpha on cell culture. The affinity of these aptamers are different and may related to their structure. These ssDNA aptamers are potential for the treatment and diagnosis of hTNFalpha related diseases.
15591425 Cytokines link osteoblasts and inflammation: microarray analysis of interleukin-17- and TN 2005 Mar The novel cytokine interleukin (IL)-17 has been implicated in many infectious and autoimmune settings, especially rheumatoid arthritis. Consistent with its proinflammatory effects on bone, osteoblast cells are highly responsive to IL-17, particularly in combination with other inflammatory cytokines. To better understand the spectrum of activities controlled by IL-17, we globally profiled genes regulated by IL-17 and tumor necrosis factor alpha (TNF-alpha) in the preosteoblast cell line MC3T3-E1. Using Affymetrix microarrays, 80-90 genes were up-regulated, and 19-50 genes were down-regulated with IL-17 and TNF-alpha as compared with TNF-alpha alone. These included proinflammatory chemokines and cytokines, inflammatory genes, transcriptional regulators, bone-remodeling genes, signal transducers, cytoskeletal genes, genes involved in apoptosis, and several unknown or unclassified genes. The CXC family chemokines were most dramatically induced by IL-17 and TNF-alpha, confirming the role of IL-17 as a potent mediator of inflammation and neutrophil recruitment. Several transcription factor-related genes involved in inflammatory gene expression were also enhanced, including molecule possessing ankyrin repeats induced by lipopolysaccharide/inhibitor of kappaBzeta (MAIL/kappaBzeta), CCAAT/enhancer-binding protein delta (C/EBPdelta), and C/EBPbeta. We also identified the acute-phase gene lipocalin-2 (LCN2/24p3) as a novel IL-17 target, which is regulated synergistically by TNF-alpha and IL-17 at the level of its promoter. A similar but not identical pattern of genes was induced by IL-17 and TNF-alpha in ST2 bone marrow stromal cells and murine embryonic fibroblasts. This study provides a profile of genes regulated by IL-17 and TNF-alpha in osteoblasts and suggests that in bone, the major function of IL-17 is to cooperate and/or synergize with other cytokines to amplify inflammation.
15585788 Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and 2004 Dec Most humans depend on sun exposure to satisfy their requirements for vitamin D. Solar ultraviolet B photons are absorbed by 7-dehydrocholesterol in the skin, leading to its transformation to previtamin D3, which is rapidly converted to vitamin D3. Season, latitude, time of day, skin pigmentation, aging, sunscreen use, and glass all influence the cutaneous production of vitamin D3. Once formed, vitamin D3 is metabolized in the liver to 25-hydroxyvitamin D3 and then in the kidney to its biologically active form, 1,25-dihydroxyvitamin D3. Vitamin D deficiency is an unrecognized epidemic among both children and adults in the United States. Vitamin D deficiency not only causes rickets among children but also precipitates and exacerbates osteoporosis among adults and causes the painful bone disease osteomalacia. Vitamin D deficiency has been associated with increased risks of deadly cancers, cardiovascular disease, multiple sclerosis, rheumatoid arthritis, and type 1 diabetes mellitus. Maintaining blood concentrations of 25-hydroxyvitamin D above 80 nmol/L (approximately 30 ng/mL) not only is important for maximizing intestinal calcium absorption but also may be important for providing the extrarenal 1alpha-hydroxylase that is present in most tissues to produce 1,25-dihydroxyvitamin D3. Although chronic excessive exposure to sunlight increases the risk of nonmelanoma skin cancer, the avoidance of all direct sun exposure increases the risk of vitamin D deficiency, which can have serious consequences. Monitoring serum 25-hydroxyvitamin D concentrations yearly should help reveal vitamin D deficiencies. Sensible sun exposure (usually 5-10 min of exposure of the arms and legs or the hands, arms, and face, 2 or 3 times per week) and increased dietary and supplemental vitamin D intakes are reasonable approaches to guarantee vitamin D sufficiency.
12674340 Associations among disease conditions, bone mineral density, and prevalent vertebral defor 2003 Apr This cross-sectional cohort study of 5566 women and 2187 men 50 years of age and older in the population-based Canadian Multicentre Osteoporosis Study was conducted to determine whether reported past diseases are associated with bone mineral density or prevalent vertebral deformities. We examined 12 self-reported disease conditions including diabetes mellitus (types 1 or 2), nephrolithiasis, hypertension, heart attack, rheumatoid arthritis, thyroid disease, breast cancer, inflammatory bowel disease, neuromuscular disease, Paget's disease, and chronic obstructive pulmonary disease. Multivariate linear and logistic regression analyses were performed to determine whether there were associations among these disease conditions and bone mineral density of the lumbar spine, femoral neck, and trochanter, as well as prevalent vertebral deformities. Bone mineral density measurements were higher in women and men with type 2 diabetes compared with those without after appropriate adjustments. The differences were most notable at the lumbar spine (+0.053 g/cm2), femoral neck (+0.028 g/cm2), and trochanter (+0.025 g/cm2) in women, and at the femoral neck (+0.025 g/cm2) in men. Hypertension was also associated with higher bone mineral density measurements for both women and men. The differences were most pronounced at the lumbar spine (+0.022 g/cm2) and femoral neck (+0.007 g/cm2) in women and at the lumbar spine (+0.028 g/cm2) in men. Although results were statistically inconclusive, men reporting versus not reporting past nephrolithiasis appeared to have clinically relevant lower bone mineral density values. Bone mineral density differences were -0.022, -0.015, and -0.016 g/cm2 at the lumbar spine, femoral neck, and trochanter, respectively. Disease conditions were not strongly associated with vertebral deformities. In summary, these cross-sectional population-based data show that type 2 diabetes and hypertension are associated with higher bone mineral density in women and men, and nephrolithiasis may be associated with lower bone mineral density in men. The importance of these associations for osteoporosis case finding and management require further and prospective studies.
12639678 Effect of castration on acetyl salicylic acid metabolism in rabbits. 2003 Mar OBJECTIVES: The biotransformation of acetyl salicylic acid (ASA) differs within species, and gender differences have been documented and attributed to the effect of sex hormones. Castration remains a standard therapy for men with advanced prostate cancer. We studied the effect of castration on the metabolism of ASA in rabbits to find out whether the metabolism of ASA is adversely affected after castration. METHODS: ASA in doses of 12.5, 25, and 50 mg/kg body weight was given intravenously to male and female prepubertal and adult rabbits, castrated adult male rabbits, and castrated male rabbits given testosterone (3 animals per group). Blood samples were collected at 0, 10, 30, 60, 120, and 180 minutes. The high-performance liquid chromatography method was used for the quantitation of salicylic acid (SA) in serum. The percentage of SA not metabolized was determined by comparing the serum level at 10 and 180 minutes for each group. RESULTS: At a dose of 50 mg/kg in the adult rabbits, the mean +/- SD of SA in serum at 10 and 180 minutes was 146.54 +/- 29.54 microg/mL and 19.12 +/- 5.93 microg/mL for males, 158.25 +/- 6.70 microg/mL and 33.24 +/- 2.78 microg/mL for females, 229.72 +/- 47.85 microg/mL and 44.33 +/- 5.64 microg/mL for castrated male rabbits, and 170.88 +/- 12.03 microg/mL and 68.1 +/- 37.54 microg/mL for castrated male rabbits given testosterone, respectively. Also, at 180 minutes, the percentage of SA not metabolized in adult male rabbits was 12.82% +/- 1.65% compared with 21.04% +/- 2.14% (P <0.01) in adult females, 19.53% +/- 1.73% (P <0.01) in castrated adult male rabbits, and 38.95% +/- 19.48% (P <0.001) in castrated male rabbits given testosterone. At all doses of ASA, the serum SA concentration in male and female prepubertal rabbits was not significantly different for each time point. CONCLUSIONS: These results indicate that male rabbits are able to metabolize ASA faster than are females. After castration, this ability is significantly decreased. If these experimental results are confirmed in humans, men who are undergoing hormonal manipulation for advanced prostate cancer and who require high-dose ASA, such as in the treatment of stroke or rheumatoid arthritis or as an antioxidant, may need lower doses to reduce the possible toxic effects of ASA.