Browse

Search for: rheumatoid arthritis    methotrexate    autoimmune disease    biomarker    gene expression    GWAS    HLA genes    non-HLA genes   

ID PMID Title PublicationDate abstract
17067557 Melittin inhibits inflammatory target gene expression and mediator generation via interact 2007 Jan 15 We previously found that bee venom (BV) and melittin (a major component of BV) has anti-inflammatory effect by reacting with the sulfhydryl group of p50 of NF-kappaB. Since the sulfhydryl group is present in IkappaB kinase (IKKalpha and IKKbeta), anti-inflammatory effect of melittin via interaction with IKKs was investigated. We first examined binding of melittin to IKKs using surface plasmon resonance analyzer. Melittin binds to IKKalpha (K(d) = 1.34 x 10(-9) M) and IKKbeta (K(d) = 1.01 x 10(-9) M). Consistent with the high binding affinity, melittin (5 and 10 microg/ml) and BV (0.5, 1 and 5 microg/ml) suppressed sodium nitroprusside, TNF-alpha and LPS induced-IKKbeta and IKKbeta activities, IkappaB release, and NF-kappaB activity as well as the expressions of iNOS and COX-2, and the generation of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) in Raw 264.7 mouse macrophages and synoviocytes obtained from rheumatoid arthritis patients. The binding affinities of melittin to mutant IKKs, was reduced, and the inhibitory effect of melittin on IKK and NF-kappaB activities, and NO and PGE(2) generation were abrogated by the reducing agents or in Raw 264.7 transfected with mutant plasmid IKKalpha (C178A) or IKKbeta (C179A). These results suggest that melittin binding to the sulfhydryl group of IKKs resulted in reduced IKK activities, IkappaB release, NF-kappaB activity and generation of inflammatory mediators, indicating that IKKs may be also anti-inflammatory targets of BV.
16966257 The influence of pregnancy on the development of autoimmunity in chronic lymphocytic leuke 2006 Aug To examine whether pregnancy influences the development of autoimmunity in chronic lymphocytic leukemia (CLL), we studied 591 consecutive CLL patients (202 post-menopausal women and 389 men). The mean observation time for all patients was 3.8 years, corresponding to approximately 2200 person-years of follow-up. Autoimmune manifestations were analyzed in 194 women with known obstetric history and known number of long-term sexual partners, and in the 389 male CLL patients for comparison. One hundred and fifty-nine of the CLL patients exhibited autoimmune manifestations, 38% in females and 21% in men. In female CLL patients, the frequency of autoimmunity and the number of pregnancies and the number of partners were strongly correlated. Each of the major autoimmune types approximately doubled in frequency for each additional pregnancy. The impact of pregnancy on expressed autoimmunity increased with each additional sexual partner (the odds of autoimmunity increased 11 times with each long-term sexual partner). The average numbers of pregnancies in female CLL patients with and without autoimmunity were 4.92 and 2.24, respectively (P < 0.001). Coombs' positive autoimmune anemia, a gastric ulcer with parietal cell autoantibodies and idiopathic thrombocytopenic purpura were equally common in women and men, whereas autoimmune thyroiditis, Sjögren's syndrome, rheumatoid arthritis and systemic lupus erythematosus were seen in higher rates in women than in men. The spectrum of autoimmunity suggests that pregnancy-related alloimmunization may be involved in the development of autoimmunity in CLL.
16948641 Humanized transgenic mice expressing HLA DR4-DQ3 haplotype: reconstitution of phenotype an 2006 Sep Many autoimmune conditions have close genetic linkages to particular human histocompatibility leukocyte antigen (HLA) class II genes. With the aim of establishing a murine model of autoimmune disease, we have generated an HLA DR4-DQ3 haplotype transgenic (Tg) mouse that expresses a 440-kb yeast artificial chromosome harbouring DRA, DRB1*040101, DRB4*010301, DQA1*030101, DQB1*0302 and all the internal regulatory segments. This Tg mouse line was crossed to human CD4 (hCD4) Tg mice and endogenous class II knockout mice (I-A(o/o) and I-E(o/o)) lines to generate a DR4-DQ3.hCD4.IAE(o/o) Tg line. The Tg DR and DQ molecules are expressed on the physiological cell types in these animals, i.e. on most B cells (>85%), dendritic cells (DCs) and macrophages but not on T cells, with levels of expression comparable with those of human B cells (where DR > DQ expression). The DR4/DQ3 transgenes fully reconstituted the CD4 T-cell compartment, in both the thymus and the periphery, and the analysis of the T-cell receptor repertoire in the Tg mice confirmed that these class II molecules were able to mediate thymic selection of a broad range of Vbeta families. HLA DR4- and DQ3-restricted T-cell responses were elicited following immunization with known T-cell determinants presented by these molecules. Furthermore, the DR4-DQ3-restricted CD4(+) T cells conferred protective antibody-mediated immunity against an otherwise lethal infection with Salmonella enterica var. typhimurium. These new DR4-DQ3 Tg mice should prove to be valuable tools for dissecting the importance of this class II haplotype in autoimmune disorders like rheumatoid arthritis.
16411065 Prolactin and autoimmunity. 2005 The interrelationship between prolactin (PRL) and the immune system have been elucitaded in the last decade, opening new important horizons in the field of the immunoendocrinology. PRL is secreted not only by anterior pituitary gland but also by many extrapituitary sites including the immune cells. The endocrine/paracrine PRL has been shown to stimulate the immune cells by binding to PRL receptors. Increased PRL levels, frequently described in autoimmune diseases, could depend on the enhancement of coordinated bi-directional communications between PRL and the immune system observed in these diseases. Hyperprolactinemia has been described in the active phase of some non organ-specific autoimmune diseases, as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) and organ-specific autoimmune diseases, as celiac disease, type 1 diabetes mellitus, Addison's disease, autoimmune thyroid diseases. In these diseases PRL increases the syntesis of IFNgamma and IL-2 by Th1 lymphocytes. Moreover, PRL activates Th2 lymphocytes with autoantibody production. Of particular interest is the association between hyperprolactinemia and levels of anti DNA antibodies, islet cell antibodies (ICA), thyreoglobulin antibodies (TgAb), thyroperoxidase antibodies (TPOAb), adrenocortical antibodies (ACA), transglutaminase antibodies (tTGAb) in SLE, in type 1 diabetes mellitus, in Hashimoto's thyroiditis, in Addison's disease and in celiac disease, respectively. High levels of PRL have been also frequently detected in patients with lymphocytic hypophysitis (LYH). Several mechanisms have been invoked to explain the hyperprolactinemia in LYH. The PRL increase could be secondary to the inflammatory process of the pituitary gland but, on the other hand, this increase could have a role in enhancing the activity of the immune process in LYH. Moreover, the detection of antipituitary antibodies targeting PRL-secreting cells in some patients with idiopathic hyperprolactinemia suggests the occurrence of a possible silent LYH in these patients. Finally, the role of anti-prolactinemic drugs to inactivate the immune process in LYH is still discussed.
16391555 Evaluating the role of the 620W allele of protein tyrosine phosphatase PTPN22 in Crohn's d 2006 Mar The 620W allele of PTPN22 has been associated with susceptibility to several different forms of chronic inflammatory disease, including Type 1 diabetes (T1D), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and autoimmune thyroiditis (AIT). We set out to explore its possible role in two other inflammatory diseases: multiple sclerosis (MS) and Crohn's disease (CD). In our cohort of 496 MS trios from the United Kingdom, we observed reduced transmission of the PTPN22 620W allele. The CD sample consisted of 169 trios as well as 249 cases of CD with their 207 matched control subjects collected in the province of Québec, Canada; there was also no evidence of association between the PTPN22 620W allele and susceptibility for CD. Pooled analyses combining our data with published data assessed a total of 1496 cases of MS and 1019 cases of CD but demonstrated no evidence of association with either disease. Given the modest odds ratios of known risk alleles for inflammatory diseases, these analyses do not exclude a role for the PTPN22 allele in susceptibility to CD or MS, but they do suggest that such a putative role would probably be more modest than that reported so far in T1D, RA, SLE, and AIT.
16336962 Signal transduction by VEGF receptors in regulation of angiogenesis and lymphangiogenesis. 2006 Mar 10 The VEGF/VPF (vascular endothelial growth factor/vascular permeability factor) ligands and receptors are crucial regulators of vasculogenesis, angiogenesis, lymphangiogenesis and vascular permeability in vertebrates. VEGF-A, the prototype VEGF ligand, binds and activates two tyrosine kinase receptors: VEGFR1 (Flt-1) and VEGFR2 (KDR/Flk-1). VEGFR1, which occurs in transmembrane and soluble forms, negatively regulates vasculogenesis and angiogenesis during early embryogenesis, but it also acts as a positive regulator of angiogenesis and inflammatory responses, playing a role in several human diseases such as rheumatoid arthritis and cancer. The soluble VEGFR1 is overexpressed in placenta in preeclampsia patients. VEGFR2 has critical functions in physiological and pathological angiogenesis through distinct signal transduction pathways regulating proliferation and migration of endothelial cells. VEGFR3, a receptor for the lymphatic growth factors VEGF-C and VEGF-D, but not for VEGF-A, regulates vascular and lymphatic endothelial cell function during embryogenesis. Loss-of-function variants of VEGFR3 have been identified in lymphedema. Formation of tumor lymphatics may be stimulated by tumor-produced VEGF-C, allowing increased spread of tumor metastases through the lymphatics. Mapping the signaling system of these important receptors may provide the knowledge necessary to suppress specific signaling pathways in major human diseases.
16320828 Curcumin protects human chondrocytes from IL-l1beta-induced inhibition of collagen type II 2005 Nov Interleukin 1beta (IL-1beta) is a pleiotropic pro-inflammatory cytokine that plays a key role in mediating cartilage degradation in osteoarticular disorders such as osteoarthritis (OA) and rheumatoid arthritis (RA). At the cellular level, IL-1beta activates matrix degrading enzymes, down-regulates expression of matrix components and induces chondrocyte apoptosis. Curcumin (diferuloylmethane) is an anti-inflammatory phytochemical agent that has recently been shown to antagonize the pro-inflammatory effects of cytokines in chondrocytes and other cells. To test the hypothesis that curcumin also protects chondrocytes from morphological alterations induced by IL-1beta, we investigated its in vitro effects on apoptotic signalling proteins and key cartilage-specific matrix components in IL-1beta-stimulated chondrocytes. Human articular chondrocytes were pre-treated with 10 ng/mI IL-1beta alone for 30 min before being co-treated with IL-1beta and 50 microM curcumin for 5, 15 or 30 min, respectively. The ultrastructural morphology of chondrocytes was investigated by transmission electron microscopy. The production of collagen type II, the adhesion and signal transduction receptor beta1-integrin, the apoptosis marker activated caspase-3 was analysed by immunohistochemistry, immunoelectron microscopy and Western blotting. Transmission electron microscopy of chondrocytes stimulated with IL-1beta revealed early degenerative changes which were relieved by curcumin co-treatment. The suppression of collagen type II and beta1-integrin synthesis by IL-1beta was inhibited by curcumin. Additionally, curcumin antagonized IL-1beta-induced caspase-3 activation in a time-dependent manner. This study clearly demonstrates that curcumin exerts anti-apoptotic and anti-catabolic effects on IL-1beta-stimulated articular chondrocytes. Therefore curcumin may have novel therapeutic potential as an adjunct nutraceutical chondroprotective agent for treating OA and related osteoarticular disorders.
16259055 Molecular targets of dietary polyphenols with anti-inflammatory properties. 2005 Oct 31 There is persuasive epidemiological and experimental evidence that dietary polyphenols have anti-inflammatory activity. Aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) have long been used to combat inflammation. Recently, cyclooxygenase (COX) inhibitors have been developed and recommended for treatment of rheumatoid arthritis (RA) and osteoarthritis (OA). However, two COX inhibitors have been withdrawn from the market due to unexpected side effects. Because conventional therapeutic and surgical approaches have not been able to fully control the incidence and outcome of many inflammatory diseases, there is an urgent need to find safer compounds and to develop mechanism-based approaches for the management of these diseases. Polyphenols are found in many dietary plant products, including fruits, vegetables, beverages, herbs, and spices. Several of these compounds have been found to inhibit the inflammation process as well as tumorigenesis in experimental animals; they can also exhibit potent biological properties. In addition, epidemiological studies have indicated that populations who consume foods rich in specific polyphenols have lower incidences of inflammatory disease. This paper provides an overview of the research approaches that can be used to unravel the biology and health effects of polyphenols. Polyphenols have diverse biological effects, however, this review will focus on some of the pivotal molecular targets that directly affect the inflammation process.
16216008 Calmodulin is a critical regulator of osteoclastic differentiation, function, and survival 2006 Jan 1 Increased osteoclastic resorption and subsequent bone loss are common features of many debilitating diseases including osteoporosis, bone metastases, Paget's disease, and rheumatoid arthritis. While rapid progress has been made in elucidating the signaling pathways directing osteoclast differentiation and function, a comprehensive picture is far from complete. Here, we explore the role of the Ca(2+)-activated regulator calmodulin in osteoclastic differentiation, functional bone resorption, and apoptosis. During active bone resorption, calmodulin expression is increased, and calmodulin concentrates at the ruffled border, the organelle utilized for acid transport and bone dissolution. Pharmacologic inhibitors of calmodulin, several of which are already used clinically as anti-cancer and anti-psychotic agents, inhibit osteoclastic acid transport, suggesting their potential as bone-sparing drugs. Recent studies also implicate calmodulin in osteoclast apoptosis through a mechanism involving its direct interaction with the death receptor Fas. During osteoclastogenesis, RANKL-induction stimulates a rise in intracellular Ca2+, which in turn activates calmodulin and its downstream effectors. In particular, the Ca(2+)/calmodulin-dependent phosphatase calcineurin and its targets, the NFAT family of transcription factors, have been posited as the master regulators of osteoclastogenesis. However, recent in vivo and in vitro studies demonstrate that another Ca(2+)/calmodulin-regulated effector protein, CaMKII, is also involved. CaMKII(+/-) mutant mice have reduced osteoclast numbers, and CaMKII antagonists inhibit osteoclastogenesis in vitro. Furthermore, CaMKII is known to activate AP-1 transcription factors, which are also required for RANKL-induced osteoclast gene transcription, and recent findings suggest that CaMKII can down-regulate gp130, a cytokine receptor involved in bone remodeling and implicated in numerous osteo-articular diseases.
15970928 Atiprimod blocks STAT3 phosphorylation and induces apoptosis in multiple myeloma cells. 2005 Jul 11 Multiple myeloma (MM) accounts for 1 % of all cancer deaths. Although treated aggressively, almost all myelomas eventually recur and become resistant to treatment. Atiprimod (2-(3-Diethylaminopropyl)-8,8-dipropyl-2-azaspiro[4,5] decane dimaleate) has exerted anti-inflammatory activities and inhibited oeteoclast-induced bone resorption in animal models and been well tolerated in patients with rheumatoid arthritis in phase I clinical trials. Therefore, we investigated its activity in MM cells and its mechanism of action. We found that Atiprimod inhibited proliferation of the myeloma cell lines U266-B1, OCI-MY5, MM-1, and MM-1R in a time- and dose-dependent manner. Atiprimod blocked U266-B1 myeloma cells in the G(0)/G(1) phase, preventing cell cycle progression. Furthermore, Atiprimod inhibited signal transducer and activator of transcription (STAT) 3 activation, blocking the signalling pathway of interleukin-6, which contributes to myeloma cell proliferation and survival, and downregulated the antiapoptotic proteins Bcl-2, Bcl-X(L), and Mcl-1. Incubation of U266-B1 myeloma cells with Atiprimod induced apoptosis through the activation of caspase 3 and subsequent cleavage of the DNA repair enzyme poly(adenosine diphosphate-ribose) polymerase. Finally, Atiprimod suppressed myeloma colony-forming cell proliferation in fresh marrow cells from five patients with newly diagnosed MM in a dose-dependent fashion. These data suggest that Atiprimod has a role in future therapies for MM.
15917650 Inhibition of c-fms by imatinib: expanding the spectrum of treatment. 2005 Jul Imatinib is a selective protein tyrosine kinase inhibitor currently used in the treatment of chronic myeloid leukaemia (CML). It specifically suppresses the growth of bcr-abl expressing CML progenitor cells by blocking the ATP-binding site of the kinase domain of bcr-abl. Imatinib also inhibits the c-abl, platelet derived growth factor receptor (PDGFR), abl-related gene and stem cell factor receptor, c-kit, protein tyrosine kinases. It is through inhibition of c-kit that imatinib is also used clinically in the treatment of gastrointestinal stromal tumours. We have recently demonstrated that imatinib also specifically targets the macrophage colony stimulating factor receptor, c-fms, at therapeutic concentrations. Although this finding has important implications with regard to potential side effects in patients currently receiving imatinib therapy, these results suggest that imatinib may also be useful in the treatment of diseases where c-fms is implicated. This includes breast and ovarian cancer and inflammatory conditions such as rheumatoid arthritis. We also speculate that imatinib may be used in diseases where bone destruction occurs due to excessive osteoclast activity, such as in the haematologic malignancy, multiple myeloma.
15914330 Chemokine production and E-selectin expression in activated endothelial cells are inhibite 2005 Jul Endothelial cells play an important role in inflammatory diseases like rheumatoid arthritis by recruitment of inflammatory cells. The cytokines TNF-alpha and IL-1beta are major inducers of endothelial cell activation and are stimulators of inflammatory signal transduction pathway involving p38 MAPK (mitogen-activated protein kinase). The present study investigated the effects of p38 MAPK inhibition on cell adhesion molecule (CAM) expression and chemokine production by endothelial cells both on mRNA and protein level. Pre-treatment of endothelial cells with the pharmacologically relevant concentration of 1 microM of the p38 MAPK inhibitor RWJ 67657 reduced TNF-alpha and IL-1beta induced mRNA and membrane expression of E-selectin. Moderate inhibitory effects on ICAM-1 and VCAM-1 expression were found. Significant reduction of mRNA expression and protein production of the inflammatory cytokine IL-6 and the chemokines IL-8 and MCP-1 was demonstrated. Treatment with RWJ 67657 could lead to reduced leukocyte infiltration by the reduction of E-selectin expression and chemokine production.
15908374 Gamma interferon positively modulates Actinobacillus actinomycetemcomitans-specific RANKL+ 2005 Jun Recent studies have shown the biological and clinical significance of signaling pathways of osteogenic cytokines RANKL-RANK/OPG in controlling osteoclastogenesis associated with bone pathologies, including rheumatoid arthritis, osteoporosis, and other osteolytic disorders. In contrast to the inhibitory effect of gamma interferon (IFN-gamma) on RANKL-mediated osteoclastogenesis reported recently, alternative new evidence is demonstrated via studies of experimental periodontitis using humanized NOD/SCID and diabetic NOD mice and clinical human T-cell isolates from diseased periodontal tissues, where the presence of increasing IFN-gamma is clearly associated with (i) enhanced Actinobacillus actinomycetemcomitans-specific RANKL-expressing CD4(+) Th cell-mediated alveolar bone loss during the progression of periodontal disease and (ii) a concomitant and significantly increased coexpression of IFN-gamma in RANKL(+) CD4(+) Th cells. Therefore, there are more complex networks in regulating RANKL-RANK/OPG signaling pathways for osteoclastogenesis in vivo than have been suggested to date.
15723623 Matrix metalloproteinase inhibitors: a review on pharmacophore mapping and (Q)SARs results 2005 The matrix metalloproteinases (MMPs) are a family of more than 20 enzymes that are intimately involved in tissue remodelling. These zinc-containing endopeptidases consist of several subsets of enzymes, including collagenase, stromelysins and gelatinases and are involved in the degradation of the extracellullar matrix (ECM) that forms the connective material between cells and around tissues. Disease processes associated with the MMPs are generally related to imbalance between the inhibition and activation of MMPs resulting in excessive degradation of the ECM. These indications include osteoarthritis rheumatoid arthritis, tumour metastasis and congestive heart failure. Inhibitors for these enzymes have been developed for the treatment of a starthingly wide array of disease process where matrix remodelling plays a key role. There are three major components to most MMP inhibitors- the zinc binding group ZBG, the peptidic backbone and the pocket occupying side chain. Most MMPs inhibitors are classified according to their ZBG. Inhibitors interactions at active-site zinc plays a critical role in defining the binding mode and relative inhibitor potency. The majority of MMP inhibitors reported in the literature contain an effective zinc binding group (e.g. hydroxamic acid, carboxylic acid, sulfhydryl group) that is either generally substituted with a peptide-like structure that mimics the substrates that they cleave or appended to smaller side chains that may interact with specific subsites (e.g., P1', P2', P3') within the active site. Although carboxylates exhibit weaker zinc binding properties than hydroxamates, they are known to show better oral bioavailability and are less prone to metabolic degradation. The expected loss of binding affinity after replacement of hydroxamates against carboxylates is faced by adequate choice of elongated S1' directed substituents. The need for novel selective MMP inhibitors makes them an attractive target for the QSAR and molecular modelling. 3-D QSAR models were derived using CoMFA, CoMSIA and GRID approaches leading to the identification of binding regions where steric, electronic or hydrophobic effects are important for affinity. Some structural requirements essential for achieving high binding affinity and selectivity are: an acidic unit tightly anchored through four contact points, bidentate chelation of Zn2+, carbonyl groups for hydrogen bonding, more than two extra units for hydrogen bonds, a hydrophobic moiety.
15694227 Cytokines and major depression. 2005 Feb In the research field of psychoneuroimmunology, accumulating evidence has indicated the existence of reciprocal communication pathways between nervous, endocrine and immune systems. In this respect, there has been increasing interest in the putative involvement of the immune system in psychiatric disorders. In the present review, the role of proinflammatory cytokines, such as interleukin (IL)-1, tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma, in the aetiology and pathophysiology of major depression, is discussed. The 'cytokine hypothesis of depression' implies that proinflammatory cytokines, acting as neuromodulators, represent the key factor in the (central) mediation of the behavioural, neuroendocrine and neurochemical features of depressive disorders. This view is supported by various findings. Several medical illnesses, which are characterised by chronic inflammatory responses, e.g. rheumatoid arthritis, have been reported to be accompanied by depression. In addition, administration of proinflammatory cytokines, e.g. in cancer or hepatitis C therapies, has been found to induce depressive symptomatology. Administration of proinflammatory cytokines in animals induces 'sickness behaviour', which is a pattern of behavioural alterations that is very similar to the behavioural symptoms of depression in humans. The central action of cytokines may also account for the hypothalamic-pituitary-adrenal (HPA) axis hyperactivity that is frequently observed in depressive disorders, as proinflammatory cytokines may cause HPA axis hyperactivity by disturbing the negative feedback inhibition of circulating corticosteroids (CSs) on the HPA axis. Concerning the deficiency in serotonergic (5-HT) neurotransmission that is concomitant with major depression, cytokines may reduce 5-HT levels by lowering the availability of its precursor tryptophan (TRP) through activation of the TRP-metabolising enzyme indoleamine-2,3-dioxygenase (IDO). Although the central effects of proinflammatory cytokines appear to be able to account for most of the symptoms occurring in depression, it remains to be established whether cytokines play a causal role in depressive illness or represent epiphenomena without major significance.
15652280 Cheongyeolsaseuptang inhibits production of TNF-alpha, IL-6 and IL-8 as well as NF-kappa B 2005 Feb 10 Traditional Korean medicine, Cheongyeolsaseuptang (CYSST) has been widely applied as a treatment of rheumatoid arthritis (RA) in Korea. However, its effect in experimental models remains unknown. Recent reports suggest that in patients with RA, synovial mast cells increase in number and show signs of activation and production of cytokines. In this study, we investigated the effect of CYSST on production of cytokines by activated human mast cell line, HMC-1. When CYSST (1mg/ml) was added, the production of tumor necrosis factor-alpha, interleukin (IL)-6, and IL-8 was significantly inhibited about 37, 33.6, and 48%, respectively on phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated HMC-1 cells. In addition, CYSST inhibited PMA plus A23187-induced activation of nuclear factor-kappaB. These findings may help understanding the mechanism of action of this medicine leading to control activated mast cells on inflammatory condition like RA.
17188670 Beneficial effects of Murraya koenigii leaves on antioxidant defense system and ultra stru 2007 Jan 30 Oxidative stress and oxidative damage to tissues are common end points of chronic diseases such as atherosclerosis, diabetes, and rheumatoid arthritis. Oxidative stress in diabetes coexists with a reduction in the antioxidant status, which can further increase the deleterious effects of free radicals. The aim of the present study was to evaluate the possible protective effects of Murraya koenigii leaves extract against beta-cell damage and antioxidant defense systems of plasma and pancreas in streptozotocin induced diabetes in rats. The levels of glucose and glycosylated hemoglobin in blood and insulin, Vitamin C, Vitamin E, ceruloplasmin, reduced glutathione and TBARS were estimated in plasma of control and experimental groups of rats. To assess the changes in the cellular antioxidant defense system such as the level of reduced glutathione and activities of superoxide dismutase, catalase and glutathione peroxidase were assayed in pancreatic tissue homogenate. The levels of glucose, glycosylated hemoglobin, insulin, TBARS, enzymatic and non-enzymatic antioxidants were altered in diabetic rats. These alterations were reverted back to near control levels after the treatment of M. koenigii leaves extract. Transmission electron microscopic studies also revealed the protective nature of M. koenigii leaves on pancreatic beta-cells. These findings suggest that M. koenigii treatment exerts a therapeutic protective nature in diabetes by decreasing oxidative stress and pancreatic beta-cell damage. The antioxidant effect of the M. koenigii extract was compared with glibenclamide, a well-known hypoglycemic drug.
17109473 Expression and function of NKG2D in CD4+ T cells specific for human cytomegalovirus. 2006 Dec The human NKG2D killer lectin-like receptor (KLR) is coupled by the DAP10 adapter to phosphoinositide 3-kinase (PI3 K) and specifically interacts with different stress-inducible molecules (i.e. MICA, MICB, ULBP) displayed by some tumour and virus-infected cells. This KLR is commonly expressed by human NK cells as well as TCRgammadelta(+) and TCRalphabeta(+)CD8(+) T lymphocytes, but it has been also detected in CD4(+) T cells from rheumatoid arthritis and cancer patients. In the present study, we analysed NKG2D expression in human cytomegalovirus (HCMV)-specific CD4(+) T lymphocytes. In vitro stimulation of peripheral blood mononuclear cells (PBMC) from healthy seropositive individuals with HCMV promoted variable expansion of CD4(+)NKG2D(+) T lymphocytes that coexpressed perforin. NKG2D was detected in CD28(-) and CD28(dull )subsets and was not systematically associated with the expression of other NK cell receptors (i.e. KIR, CD94/NKG2 and ILT2). Engagement of NKG2D with specific mAb synergized with TCR-dependent activation of CD4(+) T cells, triggering proliferation and cytokine production (i.e. IFN-gamma and TNF-alpha). Altogether, the data support the notion that NKG2D functions as a prototypic costimulatory receptor in a subset of HCMV-specific CD4(+) T lymphocytes and thus may have a role in the response against infected HLA class II(+) cells displaying NKG2D ligands.
17094021 DA-9601 inhibits activation of the human mast cell line HMC-1 through inhibition of NF-kap 2007 Mar Mast cell-mediated allergic inflammation is involved in many diseases such as asthma, sinusitis, and rheumatoid arthritis. Mast cells induce synthesis and production of pro-inflammatory cytokines including tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 with immune regulatory properties. The formulated ethanol extract of Artemisia asiatica Nakai (DA-9601) has been reported to have antioxidative and anti-inflammatory activities. In this report, we investigated the effect of DA-9601 on the expression of pro-inflammatory cytokines by the activated human mast cell line HMC-1 and studied its possible mechanisms of action. DA-9601 dose-dependently decreased the gene expression and production of TNF-alpha, IL-1beta, and IL-6 on phorbol 12-myristate 13-acetate (PMA)- and calcium ionophore A23187-stimulated HMC-1 cells. In addition, DA-9601 attenuated PMA- and A23187-induced activation of NF-kappaB as indicated by inhibition of degradation of IkappaBalpha, nuclear translocation of NF-kappaB, NF-kappaB/DNA binding, and NF-kappaB-dependent gene reporter assay. Our in vitro studies provide evidence that DA-9601 might contribute to the treatment of mast cell-derived allergic inflammatory diseases.
17078593 [How to evaluate the cardiovascular and renal risk at the individual level?]. 2006 Sep The cardiovascular impact of the non-steroidal anti-inflammatory drugs and the higher cardiovascular mortality during treatment of inflammatory rheumatism impose a rigorous evaluation of the cardiovascular risk of rheumatic patients. Large epidemiological studies have identified risk factors for cardiovascular diseases such as the age, male gender, family history (infarct, stroke), tobacco consumption, systolic arterial pressure, renal insufficiency, hypercholesterolemia, diabetes mellitis, sedentariness, obesity and "electric" ventricular hypertrophy. Some equations make it possible to evaluate the absolute cardiovascular risk at the individual level, which corresponds to the onset risk of a stroke in the 10 years to come in a subject according to the number and importance of each of his risk factors. It has been demonstrated that the correction of one or more risk factors reduce the overall cardiovascular risk justifying the strategies for evaluating this risk to define therapeutic intervention thresholds. The impact of a long-term anti-inflammatory treatment or an inflammatory disease such as rheumatoid arthritis has not been the subject of specific epidemiological study allowing these elements to be included in an equation of the estimation of the cardiovascular risk. However, the introduction of on anti-inflammatory treatment, likely to increase the cardiovascular risk of a patient, certainly justifies an evaluation of the absolute cardiovascular risk.