947 resultados para tumor necrosis factor receptor associated factor 2


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Lipopolysaccharides from gram-negative bacteria are amongst the most common causative agents of acute lung injury, which is characterized by an inflammatory response, with cellular infiltration and the release of mediators/cytokines. There is evidence that bradykinin plays a role in lung inflammation in asthma but in other types of lung inflammation its role is less clear. In the present study we evaluated the role of the bradykinin B(1) receptor in acute lung injury caused by lipopolysaccharide inhalation and the mechanisms behind bradykinin actions participating in the inflammatory response. We found that in C57BI/6 mice, the bradykinin B(1) receptor expression was up-regulated 24 h after lipopolysaccharide inhalation. At this time, the number of cells and protein concentration were significantly increased in the bronchoalveolar lavage fluid and the mice developed airway hyperreactivity to methacholine. In addition, there was an increased expression of tumor necrosis factor-alpha, interleukin-1 beta and interferon-gamma and chemokines (monocytes chemotactic protein-1 and KC) in the bronchoalveolar lavage fluid and in the lung tissue. We then treated the mice with a bradykinin B, receptor antagonist, R-954 (Ac-Orn-[Oic(2), alpha-MePhe(5), D-beta Nal(7), Ile(8)]desArg(9)-bradykinin), 30 min after lipopolysaccharide administration. We observed that this treatment prevented the airway hyperreactivity as well as the increased cellular infiltration and protein content in the bronchoalveolar lavage fluid. Moreover, R-954 inhibited the expression of cytokines/chemokines. These results implicate bradykinin, acting through B(1) receptor, in the development of acute lung injury caused by lipopolysaccharide inhalation. (C) 2010 Elsevier B.V. All rights reserved.

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Introduction: Several lines of evidence support an immunologic involvement in obsessive-compulsive disorder (OCD): the increased prevalence of OCD in patients with rheumatic fever (RF), and the aggregation of obsessive-compulsive spectrum disorders among relatives of RF probands. Tumor necrosis factor alpha is a proinflammatory cytokine involved in RF and other autoimmune diseases. Polymorphisms in the promoter region of the TNFA gene have been associated with RE Given the association between OCD and RF, the goal of the present study was to investigate a possible association between polymorphisms within the promoter region of TNFA and OCD. Materials and methods: Two polymorphisms were investigated: -308 G/A and -238 G/A. The allelic and genotypic frequencies of these polymorphisms were examined in 111 patients who fulfilled DSM-IV criteria for OCD and compared with the frequencies in 250 controls. Results: Significant associations were observed between both polymorphisms and OCD. For -238 G/A, an association between the A allele and OCD was observed (X-2 = 12.05, p = 0.0005). A significant association was also observed between the A allele of the -308 G/A polymorphism and OCD (X-2 = 7.09, p = 0.007). Finally, a haplotype consisting of genotypes of these two markers was also examined. Significant association was observed for the A-A haplotype (p = 0.0099 after correcting for multiple testing). Discussion: There is association between the -308 G/A and -238 G/A TNFA polymorphisms and OCD in our Brazilian sample. However, these results need to be replicated in larger samples collected from different populations. (c) 2008 Elsevier Ireland Ltd. All rights reserved.

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Objective: A number of candidate genes have been implicated in the pathogenesis of obesity in humans. This study examines associations between longitudinal changes in body mass and composition and the presence of polymorphisms in the ß-3 adrenergic receptor, tumor necrosis factor-α, leptin, and leptin receptor (Lepr) in a cohort of Australian women.

Research Methods and Procedures: Healthy white Australian women (n = 335) were randomly selected from the Barwon region of Victoria and underwent baseline anthropometry and double-energy X-ray absorptiometry for assessment of body mass and adiposity. These measurements were repeated again at 2-year follow-up. Genomic DNA was extracted and used for polymerase chain reaction-based genotyping of all polymorphisms.

Results: The Pro1019Pro Lepr polymorphism was associated with longitudinal increases in body weight (p = 0.02), fat mass (p = 0.05), and body mass index (p = 0.01) in this study, and individuals homozygous for the A allele at this locus had a greater propensity to gain body fat over time. The largest effects on body composition seemed to be in individuals already obese at baseline. Changes in body weight, fat mass, percent body fat, and body mass index over a 2-year period were not associated with genetic variation in the ß-3 adrenergic receptor (Trp64Arg), tumor necrosis factor-α promoter, or leptin genes in non-obese or obese women.

Discussion: These results suggest that a Lepr polymorphism is involved in the regulation of body mass and adiposity in obese Australian white women, which may have implications for the treatment of obesity in this population.

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Objective: Our objective was to delineate the potential role of adipogenesis in insulin resistance and type 2 diabetes. Obesity is characterized by an increase in adipose tissue mass resulting from enlargement of existing fat cells (hypertrophy) and/or from increased number of adipocytes (hyperplasia). The inability of the adipose tissue to recruit new fat cells may cause ectopic fat deposition and insulin resistance.

Research Methods and Procedures: We examined the expression of candidate genes involved in adipocyte proliferation and/or differentiation [ CCAAT/enhancer-binding protein (C/EBP) alpha, C/EBPdelta, GATA domain-binding protein 3 (GATA3), C/EBPbeta, peroxisome proliferator-activated receptor (PPAR) gamma2, signal transducer and activator of transcription 5A (STAT5A), Wnt-10b, tumor necrosis factor alpha, sterol regulatory element-binding protein 1c (SREBP1c), 11 beta-hydroxysteroid dehydrogenase, PPARG angiopoietin-related protein (PGAR), insulin-like growth factor 1, PPARitalic gamma coactivator 1alpha, PPARitalic gamma coactivator 1beta, and PPARdelta] in subcutaneous adipose tissue from 42 obese individuals with type 2 diabetes and 25 non-diabetic subjects matched for age and obesity.

Results: Insulin sensitivity was measured by a 3-hour 80 mU/m2 per minute hyperinsulinemic glucose clamp (100 mg/dL). As expected, subjects with type 2 diabetes had lower glucose disposal (4.9 plusminus 1.9 vs. 7.5 plusminus 2.8 mg/min per kilogram fat-free mass; p < 0.001) and larger fat cells (0.90 plusminus 0.26 vs. 0.78 plusminus 0.17 mum; p = 0.04) as compared with obese control subjects. Three genes (SREBP1c, p < 0.01; STAT5A, p = 0.02; and PPARitalic gamma2, p = 0.02) had significantly lower expression in obese type 2 diabetics, whereas C/EBPbeta only tended to be lower (p = 0.07).

Discussion: This cross-sectional study supports the hypothesis that impaired expression of adipogenic genes may result in impaired adipogenesis, potentially leading to larger fat cells in subcutaneous adipose tissue and insulin resistance.

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The insulin-like growth factor (IGF) system is a key regulator of cell growth, survival and differentiation, and these functions are co-modulated by other growth factors including fibroblast growth factor-2 (FGF-2). To investigate IGF/FGF interactions in neuronal cells, we employed neuroblastoma cells (SK-N-MC). In serum free conditions proliferation of the SK-N-MC cells was promoted by IGF-I (25 ng/ml), but blunted by FGF-2 (50 ng/ml). IGF-I-induced proliferation was abolished in the presence of FGF-2 even when IGF-I was used at 100 ng/ml. In addition to our previously described FGF-2 induced proteolytic cleavage of IGFBP-2, we found that FGF-2 increased IGFBP-6 levels in conditioned medium (CM) without affecting IGFBP-6 mRNA abundance. Modulation of IGFBP-2 and -6 levels were not significant mechanisms involved in the blockade of IGF-I action since the potent IGF-I analogues [QAYL]IGF-I and des(1-3)IGF-I (minimal IGFBP affinity) were unable to overcome FGF-2 inhibition of cell proliferation. FGF-2 treated cells showed morphological differentiation expressing the TUJ1 neuronal marker while cells treated with IGF-I alone showed no morphological change. When IGF-I was combined with FGF-2, however, cell morphology was indistinguishable from that seen with FGF-2 alone. FGF-2 inhibited proliferation and enhanced differentiation was also associated with a 70% increase in cell death. Although IGF-I alone was potently anti-apoptotic (60% decreased), IGF-I was unable to prevent apoptosis when administrated in combination with FGF-2. Gene-array analysis confirmed FGF-2 activation of the intrinsic and extrinsic apoptotic pathways and blockade of IGF anti-apoptotic signaling. FGF-2, directly and indirectly, overcomes the proliferative and anti-apoptotic activity of IGF-I by complex mechanisms, including enhancement of differentiation and apoptotic pathways, and inhibition of IGF-I induced anti-apoptotic signalling. Modulation of IGF binding protein abundance by FGF-2 does not play a significant role in inhibition of IGF-I induced mitogenesis.

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The biomedical application of graphene quantum dots (GQDs) is a new emerging area. However, their safety data are still in scarcity to date. Particularly, the effect of GQDs on the immune system remains unknown. This study aimed to elucidate the interaction of GQDs with macrophages and the underlying mechanisms. Our results showed that GQDs slightly affected the cell viability and membrane integrity of macrophages, whereas GQDs significantly increased reactive oxygen species (ROS) generation and apoptotic and autophagic cell death with an increase in the expression level of Bax, Bad, caspase 3, caspase 9, beclin 1, and LC3-I/II and a decrease in that of Bcl-2. Furthermore, low concentrations of GQDs significantly increased the expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-8, whereas high concentrations of GQDs elicited opposite effects on the cytokines production. SB202190, a selective inhibitor of p38 mitogen-activated protein kinase (MAPK), abolished the cytokine-inducing effect of GQDs in macrophages. Moreover, GQDs significantly increased the phosphorylation of p38 MAPK and p65, and promoted the nuclear translocation of nuclear factor-κB (NF-κB). Taken together, these results show that GQDs induce ROS generation, apoptosis, autophagy, and inflammatory response via p38MAPK and NF-κB mediated signaling pathways in THP-1 activated macrophages.

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Inflammation has been pointed out as an important factor in development of chronic diseases, as diabetes. Hyperglycemia condition would be responsible by toll-like receptors, TLR2 and TLR4, and, consequently by local and systemic inflammation induction. Thus, the objective of present study was to evaluate type 1 Diabetes mellitus (T1DM) pro-inflammatory state through mRNA expression of TLRs 2 and 4 and proinflammatory cytokines IL-1β, IL-6 and TNF-α correlating to diabetic nephropathy. In order to achieve this objective, 76 T1DM patients and 100 normoglycemic (NG) subjects aged between 6 and 20 years were evaluated. T1DM subjects were evaluated as a total group DM1, and considering glycemic control (good glycemic control DM1G, and poor glycemic control DM1P) and considering time of diagnosis (before achieving 5 years of diagnosis DM1< 5yrs, and after achieving 5 years of diagnosis DM1 <5yrs). Metabolic control was evaluated by glucose and glycated hemoglobin concentrations; to assess renal function serum urea, creatinine, albumin, total protein and urinary albumin-to-creatinine ratio were determined and to evaluate hepatic function, AST and ALT serum activities were measured. Pro-inflammatory status was assessed by mRNA expression of TLRs 2 and 4 and the inflammatory cytokines IL-1β, IL-6 and TNF-α. Except for DM1G group (18.4%), DM1NC patients (81.6%) showed a poor glycemic control, with glycated hemoglobin (11,2%) and serum glucose (225,5 md/dL) concentrations significantly increased in relation to NG group (glucose: 76,5mg/dL and glycated hemoglobin: 6,9%). Significantly enhanced values of urea (20%) and ACR (20,8%) and diminished concentrations of albumin (5,7%) and total protein (13,6%) were found in T1DM patients, mainly associated to a poor glycemic control (DM1P increased values of urea: 20% and ACR:49%, and diminished of albumin: 13,6% and total protein:13,6%) and longer disease duration (DM1 <5yrs - increased values of urea: 20% and ACR:20,8%, and diminished of albumin: 14,3% and total protein:13,6%). As regarding pro-inflammatory status evaluation, significantly increased mRNA expressions were presented for TLR2 (37,5%), IL-1β (43%), IL-6 (44,4%) and TNF-α (15,6%) in T1DM patients in comparison to NG, mainly associated to DM1P (poor glycemic control TLR2: 82%, IL-1β: 36,8% increase) and DM1 <5yrs (longer time of diagnosis TLR2: 85,4%, IL-1β: 46,5% increased) groups. Results support the existence of an inflammatory state mediated by an increased expression of TLR2 and pro-inflammatory cytokines IL-1β, IL-6 and TNF-α in T1DM

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Leprosy is a complex infectious disease influenced by genetic and environmental factors. The genetic contributing factors are considered heterogeneous and several genes have been consistently associated with susceptibility like PARK2, tumor necrosis factor (TNF), lymphotoxin-alpha (LTA) and vitamin-D receptor (VDR). Here, we combined a case-control study (374 patients and 380 controls), with meta-analysis (5 studies; 2702 individuals) and biological study to test the epidemiological and physiological relevance of the interleukin-10 (IL-10) genetic markers in leprosy. We observed that the -819T allele is associated with leprosy susceptibility either in the case-control or in the meta-analysis studies. Haplotypes combining promoter single-nucleotide polymorphisms also implicated a haplotype carrying the -819T allele in leprosy susceptibility (odds ratio (OR) = 1.40; P = 0.01). Finally, we tested IL-10 production in peripheral blood mononuclear cells stimulated with Mycobacterium leprae antigens and found that -819T carriers produced lower levels of IL-10 when compared with noncarriers. Taken together, these data suggest that low levels of IL-10 during the disease outcome can drive patients to a chronic and unprotective response that culminates with leprosy.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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WE previously demonstrated that Bothrops jararaca venom (BjV) has an antitumor effect on Ehrlich ascites tumor (EAT) cells and induces an increase of polymorphonuclear leukocytes in early stages of tumor growth. It has been reported that this venom presents an important inflammatory effect when inoculated in animal models and in human snake-bites, and that cytokine levels have been detected in these cases. To evaluate whether the cytokines can be involved with the suppression of the tumoral growth, we evaluate the cytokine profile in the peritoneal cavity of mice inoculated with EAT cells and treated with BjV. Swiss mice were inoculated with EAT cells by the intraperitoneal route and treated with BjV venom (0.4 mg/kg, intraperitoneally), on the 1st, 4th, 7th, 10th, and 13th day. Mice were evaluated for cytokine levels on the 2nd, 5th, 8th, 11th and 14th day. Analysis was performed using an enzyme-linked immunosorbent assay for interleukin (IL)-1α, IL-2, IL-4, IL-6, IL-10, IL-13, and tumor necrosis factor-α (TNF-α) levels in the peritoneal washing supernatant. Results were analyzed statistically by the Kruskal-Wallis and Dunn's tests at the 5% level of significance. We observed that EAT implantation induces IL-6 production on the 11th and 14th days of tumor growth, IL-10 on the 11th day and TNF-α on the 14th day. The treatment with BjV suppresses production of these cytokines. In addition, IL-13 was produced by animals that were inoculated only with venom on the 11th and 14th days, and by the group inoculated with EAT cells and treated with venom on the 2nd and 14th days. Furthermore, we suggest that the IL-6 detected in the present study is produced by the EAT cells and the suppression of its production could be associated with the antitumor effect of BjV.

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In this study we investigated the effect of β-glucan derived from Saccharomyces cerevisiae on fungicidal activity, cytokine production and natural killer activity. Spleen and peritoneal cells from female C57BL/6 mice, previously injected (24 or 48 h) with 20 or 100 μg of glucan by i.p. route, were assayed. In vivo β-glucan administration primed spleen cells for a higher production of IL-12 and TNF-α when S. aureus was used as a stimulus. In addition, β-glucan increased NK spleen cells activity against YAC target cells. Some immunomodulatory activities not yet described for β-glucan were observed in this work. © 2005 Institute of Physiology, Academy of Sciences of the Czech Republic.

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West syndrome is a severe epilepsy, occurring in infancy, that comprises epileptic seizures known as spasms, in clusters, and a unique EEG pattern, hypsarrhythmia, with psychomotor regression. Maturation of the brain is a crucial component. The onset is within the first year of life, before 12 months of age. Patients are classified as cryptogenic (10 to 20%), when there are no known or diagnosed previous cerebral insults, and symptomatic (80 to 90%), when associated with pre-existing cerebral damages. The time interval from a brain insult to infantile spasms onset ranged from 6 weeks to 11 months. West syndrome has a time-limited natural evolutive course, usually disappearing by 3 or 4 years of age. In 62% of patients, there are transitions to another age-related epileptic encephalopathies, the Lennox-Gastaut Syndrome and severe epilepsy with multiple independent foci. Spontaneous remission and remission after viral infections may occur. Therapy with ACTH and corticosteroids are the most effective. Reports about intravenous immunoglobulins action deserve attention. There is also immune dysfunction, characterized mainly by anergy, impaired cell-mediated immunity, presence of immature thymocytes in peripheral blood, functional impairment of T lymphocytes induced by plasma inhibitory factors, and altered levels of immunoglobulins. Changes in B lymphocytes frequencies and increased levels of activated B cells have been reported. Sensitized lymphocytes to brain extract were also described. Infectious diseases are frequent and may, sometimes, cause fatal outcomes. Increase of pro-inflamatory cytokines in serum and cerebrospinal fluid of epileptic patients were reported. Association with specific HLA antigens was described by several authors (HLA-DR7, HLA-A7, HLA-DRw52, and HLA-DR5). Auto-antibodies to brain antigens, of several natures (N-methyl-d-aspartate glutamate receptor, gangliosides, brain tissue extract, synaptic membrane, and others), were described in epileptic patients and in epileptic syndromes. Experimental epilepsy studies with anti-brain antibodies demonstrated that epileptiform discharges can be obtained, producing hyperexcitability leading to epilepsy. We speculate that in genetically prone individuals, previous cerebral lesions may sensitize immune system and trigger an autoimmune disease. Antibody to brain antigens may be responsible for impairment of T cell function, due to plasma inhibitory effect and also cause epilepsy in immature brains. © 2008 Bentham Science Publishers Ltd.