459 resultados para TGF-[Bêta]1


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SETTING: A tertiary care research centre in Sao Paolo, Brazil. OBJECTIVE: To quantify interleukin (IL) 8, tumour necrosis factor alpha (TNF-alpha), vascular endothelial growth factor (VEGF) and transforming growth factor beta(1), (TGF-beta(1))in pleural fluid from tuberculous patients, correlating its values with the histopathological patterns in pleural biopsies. DESIGN: Cytokines were quantified in patients with transudatcs secondary to congestive heart failure (n = 8) and exudates secondary to tuberculosis (TB; n = 39). In parietal pleural biopsies from TB patients, the histological patterns of the inflammatory response were quantified by morphometric analysis (stereological point-counting method). RESULTS: IL-8, TNF-alpha, VEGF and TGF-beta(1) levels were higher in TB than in transudates. A positive correlation existed between components of the fibrinoid exudative phase with pleural fluid IL-8 (R = 0.52, P = 0.004) and VEGF (R = 0.42, P = 0.0021) levels. A negative correlation existed between pleural fluid IL-8 (R = -0.37, P = 0.048) and VEGF (R = -0.44, P = 0.0015) levels with tissue components of fibroproliferation. CONCLUSION: The high pleural levels of TNF-a, IL-8, VEGF and TGF-beta(1) suggest the involvement of these cytokines in the TB immunological response. The positive correlation between pleural fluid IL-8 and VEGF with the components of the acute exudative phase and the negative correlation between these cytokines with the fibroproliferative components suggest a temporary inflammatory response in the pleural space.

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Myocardial hypertrophy and dysfunction occur in response to excessive catecholaminergic drive. Adverse cardiac remodelling is associated with activation of proinflammatory cytokines in the myocardium. To test the hypothesis that exercise training can prevent myocardial dysfunction and production of proinflammatory cytokines induced by beta-adrenergic hyperactivity, male Wistar rats were assigned to one of the following four groups: sedentary non-treated (Con); sedentary isoprenaline treated (Iso); exercised non-treated (Ex); and exercised plus isoprenaline (Iso+Ex). Echocardiography, haemodynamic measurements and isolated papillary muscle were used for functional evaluations. Real-time RT-PCR and Western blot were used to quantify tumour necrosis factor alpha, interleukin-6, interleukin-10 and transforming growth factor beta(1) (TGF-beta(1)) in the tissue. NF-kappa B expression in the nucleus was evaluated by immunohistochemical staining. The Iso rats showed a concentric hypertrophy of the left ventricle (LV). These animals exhibited marked increases in LV end-diastolic pressure and impaired myocardial performance in vitro, with a reduction in the developed tension and maximal rate of tension increase and decrease, as well as worsened recruitment of the Frank-Starling mechanism. Both gene and protein levels of tumour necrosis factor alpha and interleukin-6, as well as TGF-beta(1) mRNA, were increased. In addition, the NF-kappa B expression in the Iso group was significantly raised. In the Iso+Ex group, the exercise training had the following effects: (1) it prevented LV hypertrophy; (ii) it improved myocardial contractility; (3) it avoided the increase of proinflammatory cytokines and improved interleukin-10 levels; and (4) it attenuated the increase of TGF-beta(1) mRNA. Thus, exercise training in a model of beta-adrenergic hyperactivity can avoid the adverse remodelling of the LV and inhibit inflammatory cytokines. Moreover, the cardioprotection is related to beneficial effects on myocardial performance.

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Some studies have demonstrated the involvement of nuclear factor-kappa B (NF-kB) in the pathogenesis of glomerulonephritis. The aim of our study was twofold: (1) to analyze the prognostic value of NF-kB expression in primary IgA nephropathy (IgAN) and (2) to compare the results of NF-kB expression by immunohistochemistry (IHC) and southwestern histochemistry (SWH). We analyzed 62 patients diagnosed with IgAN from 1987 to 2003. We used monoclonal antibodies to CD68 and mast cell tryptase and polyclonal antibodies to TGF-beta 1, alpha-SMA and NF-kB p65. We used SWH for the in situ detection of activated NF-kB. The results showed that NF-kB expression (mainly by SWH) correlated with clinical and histological parameters. An unfavorable clinical course of IgAN was significantly related to tubular NF-kB expression by SWH, but not by IHC. The Kaplan-Meier curves demonstrated that increased NF-kB expression, which was measured by IHC and SWH, decreased renal survival. In conclusion, the increased expression of NF-kB in the tubular area may be a predictive factor for the poor prognosis of patients with IgAN. Compared with IHC, NF-kB expression determined by SWH was correlated with a larger number of parameters of poor disease outcome.

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Common features such as elastic fibre destruction, mucoid accumulation, and smooth muscle cell apoptosis are co-localized in aneurysms of the ascending aorta of various aetiologies. Recent experimental studies reported an activation of TGF-beta in aneurysms related to Marfan (and Loeys-Dietz) syndrome. Here we investigate TGF-beta signalling in normal and pathological human ascending aortic wall in syndromic and non-syndromic aneurysmal disease. Aneurysmal ascending aortic specimens, classified according to aetiology: syndromic MFS (n = 15, including two mutations in TGFBR2), associated with BAV (n = 15) or degenerative forms (n = 19), were examined. We show that the amounts of TGF-beta 1 protein retained within and released by aneurysmal tissue were greater than for control aortic tissue, whatever the aetiology, contrasting with an unchanged TGF-beta 1 mRNA level. The increase in stored TGF-beta 1 was associated with enhanced LTBP-I protein and mRNA levels. These dysiregulations of the extracellular ligand are associated with higher phosphorylated Smad2 and Smad2 mRNA levels in the ascending aortic wall from all types of aneurysm. This activation correlated with the degree of elastic fibre fragmentation. Surprisingly, there was no consistent association between the nuclear location of pSmad2 and extracellular TGF-beta 1 and LTBP-I staining and between their respective mRNA expressions. In parallel, decorin. was focally increased in aneurysmal media, whereas biglycan was globally decreased in aneurysmal aortas. In conclusion, this study highlights independent dysregulations of TGF-beta retention and Smad2 signalling in syndromic and non-syndromic aneurysms of the ascending aorta. Copyright (C) 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

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Fibrinolytic activity is associated with presence of cystic medial degeneration in aneurysms of the ascending aorta Aims: Thoracic ascending aortic aneurysms (TAA) are characterized by elastic fibre breakdown and cystic medial degeneration within the aortic media, associated with progressive smooth muscle cell (SMC) rarefaction. The transforming growth factor (TGF)-beta/Smad2 signalling pathway is involved in this process. Because the pericellular fibrinolytic system activation is able to degrade adhesive proteins, activate matrix metalloproteinase (MMP), induce SMC disappearance and increase the bioavailability of TGF-beta, the aim was to investigate the plasminergic system in TAA. Methods and results: Ascending aortas [21 controls and 19 TAAs (of three different aetiologies)] were analysed. Immunohistochemistry showed accumulation of t-PA, u-PA and plasmin in TAAs, associated with residual SMCs. Overexpression of t-PA and u-PA was confirmed by reverse transcription-polymerase chain reaction (RT-PCR), immunoblotting and zymography on TAA extracts and culture medium conditioned by TAA. Plasminogen was present on the SMC surface and inside cytoplasmic vesicles, but plasminogen mRNA was undetectable in the TAA medial layer. Plasmin-antiplasmin complexes were detected in TAA-conditioned medium and activation of the fibrinolytic system was associated with increased fibronectin turnover. Fibronectin-related material was detected immunohistochamically in dense clumps around SMCs and colocalized with latent TGF-beta binding protein-1. Conclusions: The fibrinolytic pathway could play a critical role in TAA progression, via direct or indirect impact on ECM and consecutive modulation of TGF-beta bioavailability.

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Neospora caninum is one of the main causes of abortion and natimortality in cattle. Host immune defense is capable to inhibit tachyzoite activity during acute infection, but there is no action against bradyzoites in tissue cysts. Activation and modulation of this response is controlled by cell mediators. The real-time RT-PCR technique was employed to detect some of those mediators during N. caninum infection. Holstein and Nelore calves intramuscularly infected with tachyzoites and uninfected controls were slaughtered at the sixth day post-infection and popliteal lymph node, liver and brain cortex samples were analyzed. Real-time RT-PCR detected gene expression in all tissues. No significant variation of GAPDH gene expression was detected among groups, its amplification efficiency was similar to the other genes tested and it was used as the endogenous control for the analysis. Comparisons between infected and uninfected groups allowed the relative gene expression quantification. IFN-gamma and TNF-alpha genes showed increased expression in some samples. iNOS and TGF-beta 1 genes had some non-significant variations and IL-4 and IL-10 stayed pratically inaltered.

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The selection of housekeeping genes is critical for gene expression studies. To address this issue, four candidate housekeeping genes, including several commonly used ones, were investigated in oral squamous cell carcinoma cell lines. A simple quantitative RT-PCR approach was employed by comparing relative expression of the four candidate genes within two cancerous cell tines (HN6 and HN31) and one noncancerous cell tine (HaCaT) treated or not with EGF and TGF-beta 1. Data were analyzed using ANOVA followed by the NormFinder software program. On this basis, stability of the candidate housekeeping genes was ranked and non statistical differences were found using ANOVA test. On the other hand, the NormFinder was able to show that GAPD and TUBB presented the less variable results, representing appropriated housekeeping genes for the samples and conditions anatyzed. In conclusion, this study suggests that the GAPD and the TUBB represent adequate normalizers for gene profiting studies in OSCC cell. tines, covering, respectively, high and low expression levels genes. (C) 2008 Elsevier Ltd. All rights reserved.

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Studies investigating the immunopathological aspects of Jorge Lobo`s disease have shown that the inflammatory infiltrate consists mainly of histiocytes and multinucleated giant cells involving numerous yeast-like cells of Lacazia loboi, with the T lymphocytes more common than B lymphocytes and plasma cells. The quantification of cytokines in peripheral blood mononuclear cells culture supernatant has revealed alterations in the cytokines profile, characterized by predominance of a Th2 profile. In view of these findings and of the role of cytokines in cell interactions, the objective of the present study was to investigate the presence of the cytokines IL-10, TGF-ss 1 and TNF-alpha, as well as iNOS enzyme in granulomas induced by L. loboi. Histological sections obtained from skin lesions of 16 patients were analyzed by immunohistochemistry for the presence of these cytokines and iNOS. The results showed that TGF-ss 1 was the cytokine most frequently expressed by cells present in the inflammatory infiltrate, followed by IL-10. There was a minimum to discrete positivity of cells expressing TNF-alpha and iNOS. The results suggest that the presence of immunosuppressive cytokines in skin lesions of patients with the mycosis might be responsible for the lack of containment of the pathogen as demonstrated by the presence of numerous fungi in the granuloma.

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Despite wide clinical application, the efficacy of platelet-rich plasma (PRP) for repairing bone defects and enhancing osseointegration of metal implants is still subject of debate. This study aimed to evaluate the effects of a well-defined PRP-like mixture containing platelet-derived growth factor-BB, transforming growth factor (TGF)-beta 1, TGF-beta 2, albumin, fibronectin, and thrombospondin [growth factors (GFs) + proteins] on the development of the osteogenic phenotype on titanium (Ti) in vitro. Human alveolar bone-derived osteoblastic cells were subcultured on Ti discs and exposed during the first 7 days to osteogenic medium supplemented with GFs + proteins and to osteogenic medium alone thereafter up to 14 days. Control cultures were exposed to only osteogenic medium. Dose-response experiments were carried out using rat primary calvarial cells exposed to GFs + proteins and 1:10 or 1:100 dilutions of the mixture. Treated human-derived cell cultures exhibited a significantly higher number of cycling cells at days 1 and 4 and of total cells at days 4 and 7, significantly reduced alkaline phosphatase (ALP) activity at days 4, 7, and 10, and no Alizarin red-stained areas (calcium deposits) at day 14, indicating an impairment in osteoblast differentiation. Although the 1:10 and 1:100 dilutions of the mixture restored the proliferative activity of rat-derived osteogenic cells to control levels and promoted a significant increase in ALP activity at day 10 compared with GFs + proteins, mineralized nodule formation was only observed with the 1:100 dilution (similar to 50% of the control). These results showed that a PRP-like protein mixture inhibits development of the osteogenic phenotype in both human and rat osteoblastic cell cultures grown on Ti. (J Histochem Cytochem 57:265-276, 2009)

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Strategies to promote bone repair have included exposure of cells to growth factor (GF) preparations from blood that generally include proteins as part of a complex mixture. This study aimed to evaluate the effects of such a mixture on different parameters of the development of the osteogenic phenotype in vitro. Osteoblastic cells were obtained by enzymatic digestion of human alveolar bone and cultured under standard osteogenic conditions until subconfluence. They were subcultured on Thermanox coverslips up to 14 days. Treated cultures were exposed during the first 7 days to osteogenic medium supplemented with a GFs + proteins mixture containing the major components found in platelet extracts [plate I et-derived growth factor-BB, transforming growth factor (TGF)-beta 1, TGF-beta 2, albumin, fibronectin, and thrombospondin] and to osteogenic medium alone thereafter. Control cultures were exposed only to the osteogenic medium. Treated cultures exhibited a significantly higher number of adherent cells from day 4 onward and of cycling cells at days 1 and 4, weak alkaline phosphatase (ALP) labeling, and significantly decreased levels of ALP activity and mRNA expression. At day 14, no Alizarin red-stained nodular areas were detected in cultures treated with GFs + proteins. Results were confirmed in the rat calvaria-derived osteogenic cell culture model. The addition of bone morphogenetic protein 7 or growth and differentiation factor 5 to treated cultures upregulated Runx2 and ALP mRNA expression, but surprisingly, ALP activity was not restored. These results showed that a mixture of GFs + proteins affects the development of the osteogenic phenotype both in human and rat cultures, leading to an increase in the number of cells, but expressed a less differentiated state.

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Exposure of phosphatidylserine (PS) on cellular membranes and membrane-derived microvesicles stimulates a number of anti-inflammatory responses involved in malignant processes. Herein we show that B16F10 cells, a highly metastatic melanoma cell line, produce large quantities of PS-containing microvesicles in vitro. Tumor microvesicles increased TGF-beta(1) production by cultured macrophages and, in vivo, enhanced the metastatic potential of B16F10 cells in C57BL/6 mice, both effects being reversed by annexin V. Most strikingly, microvesicles induced melanoma metastasis in BALB/c mice, which are normally resistant to this tumor cell line. Altogether, this is the first demonstration that tumor-derived microvesicles favor the establishment of melanoma metastasis in a PS-dependent manner, possibly by down-regulating the host`s inflammatory and/or anti-tumoral immune responses. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

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In the present study the effects of bradykinin receptor antagonists were investigated in a murine model of asthma using BALB/c mice immunized with ovalbumin/alum and challenged twice with aerosolized ovalbumin. Twenty four hours later eosinophil proliferation in the bone marrow, activation (lipid bodies formation), migration to lung parenchyma and airways and the contents of the pro-angiogenic and pro-fibrotic cytokines TGF-beta and VEGF were determined. The antagonists of the constitutive B(2) (HOE 140) and inducible B(1) (R954) receptors were administered intraperitoneally 30 min before each challenge. In sensitized mice, the antigen challenge induced eosinophil proliferation in the bone marrow, their migration into the lungs and increased the number of lipid bodies in these cells. These events were reduced by treatment of the mice with the B(1) receptor antagonist. The B(2) antagonist increased the number of eosinophils and lipid bodies in the airways without affecting eosinophil counts in the other compartments. After challenge the airway levels of VEGF and TGF-beta significantly increased and the B(1) receptor antagonist caused a further increase. By immunohistochemistry techniques TGF-beta was found to be expressed in the muscular layer of small blood vessels and VEGF in bronchial epithelial cells. The B(1) receptors were expressed in the endothelial cells. These results showed that in a murine model of asthma the B(1) receptor antagonist has an inhibitory effect on eosinophils in selected compartments and increases the production of cytokines involved in tissue repair. It remains to be determined whether this effects of the B(1) antagonist would modify the progression of the allergic inflammation towards resolution or rather towards fibrosis. (C) 2009 Elsevier Ltd. All rights reserved.

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Background: The purpose of this study was to evaluate collagen deposition, mRNA collagen synthesis and TGFbeta expression in the lung tissue in an experimental model of scleroderma after collagen V-induced nasal tolerance. Methods: Female New Zealand rabbits (N = 12) were immunized with 1 mg/ml of collagen V in Freund's adjuvant (IM). After 150 days, six immunized animals were tolerated by nasal administration of collagen V ( 25 mu g/day) (IM-TOL) daily for 60 days. The collagen content was determined by morphometry, and mRNA expressions of types I, III and V collagen were determined by Real-time PCR. The TGF-beta expression was evaluated by immunostaining and quantified by point counting methods. To statistic analysis ANOVA with Bonferroni test were employed for multiple comparison when appropriate and the level of significance was determined to be p < 0.05. Results: IM-TOL, when compared to IM, showed significant reduction in total collagen content around the vessels (0.371 +/- 0.118 vs. 0.874 +/- 0.282, p < 0.001), bronchioles (0.294 +/- 0.139 vs. 0.646 +/- 0.172, p < 0.001) and in the septal interstitium (0.027 +/- 0.014 vs. 0.067 +/- 0.039, p = 0.026). The lung tissue of IM-TOL, when compared to IM, showed decreased immunostaining of types I, III and V collagen, reduced mRNA expression of types I (0.10 +/- 0.07 vs. 1.0 +/- 0.528, p = 0.002) and V (1.12 +/- 0.42 vs. 4.74 +/- 2.25, p = 0.009) collagen, in addition to decreased TGF-beta expression ( p < 0.0001). Conclusions: Collagen V-induced nasal tolerance in the experimental model of SSc regulated the pulmonary remodeling process, inhibiting collagen deposition and collagen I and V mRNA synthesis. Additionally, it decreased TGF-beta expression, suggesting a promising therapeutic option for scleroderma treatment.

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Background: The tubule-interstitial fibrosis is the hallmark of progressive renal disease and is strongly associated with inflammation of this compartment. Heme-oxygenase-1 (HO-1) is a cytoprotective molecule that has been shown to be beneficial in various models of renal injury. However, the role of HO-1 in reversing an established renal scar has not yet been addressed. Aim: We explored the ability of HO-1 to halt and reverse the establishment of fibrosis in an experimental model of chronic renal disease. Methods: Sprague-Dawley male rats were subjected to unilateral ureteral obstruction (UUO) and divided into two groups: non-treated and Hemin-treated. To study the prevention of fibrosis, animals were pre-treated with Hemin at days -2 and -1 prior to UUO. To investigate whether HO-1 could reverse established fibrosis, Hemin therapy was given at days 6 and 7 post-surgery. After 7 and/or 14 days, animals were sacrificed and blood, urine and kidney tissue samples were collected for analyses. Renal function was determined by assessing the serum creatinine, inulin clearance, proteinuria/creatininuria ratio and extent of albuminuria. Arterial blood pressure was measured and fibrosis was quantified by Picrosirius staining. Gene and protein expression of pro-inflammatory and pro-fibrotic molecules, as well as HO-1 were performed. Results: Pre-treatment with Hemin upregulated HO-1 expression and significantly reduced proteinuria, albuminuria, inflammation and pro-fibrotic protein and gene expressions in animals subjected to UUO. Interestingly, the delayed treatment with Hemin was also able to reduce renal dysfunction and to decrease the expression of pro-inflammatory molecules, all in association with significantly reduced levels of fibrosis-related molecules and collagen deposition. Finally, TGF-beta protein production was significantly lower in Hemin-treated animals. Conclusion: Treatment with Hemin was able both to prevent the progression of fibrosis and to reverse an established renal scar. Modulation of inflammation appears to be the major mechanism behind HO-1 cytoprotection.

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Pulmonary macrophages (PM), which are CD11b/CD18(+) and CD23(+), may be involved in the onset of inflammatory events caused by Paracoccidioides brasiliensis in the lungs. In the present study, we measured the nitric oxide (NO) and interleukin in PM production after intratracheal (i.t.) inoculation of an enriched beta-glucan cell wall fraction from P. brasiliensis (Fraction F1). BALB/c and C57/BL6 (B6) mice were i.t. treated with Fraction F1, and their PM were restimulated in vitro with LPS and interferon-gamma up to 14 days after treatment. Macrophages BALB/c mice produced less NO than PM from B6 mice. The lower NO production was caused by higher production of TGF-beta by pulmonary macrophages of BALB/c and was abrogated by anti-TGF-beta MoAb in vitro and in vivo. Other interleukins such as IL-10, IL-4 and a combination of IL-1, TNF-alpha and IL-6 were not involved in NO production induced by Fraction F1. Expression of CD11b increases and expression of CD23 decreases on PM of BALB/c mice after in vivo treatment whereas PM of B6 mice do not show a variation of their phenotype. Moreover, the ability of pulmonary macrophages to induce lymphocyte proliferation was reduced in mixed cultures of CD11b(+) or CD23(+) macrophages but was restored when lymphocytes were cultivated in the presence of NO inhibitor (L-NMMA). Thus, the results presented herein indicate that in BALB/c but not in B6 mice TGF- is strongly induced by Fraction 1 in PM in vivo and suppresses NO production. Low NO production by PM is associated with a change in CD11b/CD23 expression and with a high lymphocyte proliferative response. Thus, CD11b(+)/CD23(+) PM modulate NO and TGF-beta production in the pulmonary microenvironment.