95 resultados para Transforming growth factor-beta
Resumo:
Periodontal disease is a chronic inflammation of the attachment structures of the teeth, triggered by potentially hazardous microorganisms and the consequent immune-inflammatory responses. In humans, the T helper type 17 (Th17) lineage, characterized by interleukin-17 (IL-17) production, develops under transforming growth factor-beta (TGF-beta), IL-1 beta, and IL-6 signaling, while its pool is maintained by IL-23. Although this subset of cells has been implicated in various autoimmune, inflammatory, and bone-destructive conditions, the exact role of T lymphocytes in chronic periodontitis is still controversial. Therefore, in this study we investigated the presence of Th17 cells in human periodontal disease. Gingival and alveolar bone samples from healthy patients and patients with chronic periodontitis were collected and used for the subsequent assays. The messenger RNA expression for the cytokines IL-17, TGF-beta, IL-1 beta, IL-6, and IL-23 in gingiva or IL-17 and receptor activator for nuclear factor-kappa B ligand in alveolar bone was evaluated by real-time polymerase chain reaction. The production of IL-17, TGF-beta, IL-1 beta, IL-6, and IL-23 proteins was evaluated by immunohistochemistry and the presence of Th17 cells in the inflamed gingiva was confirmed by immunofluorescence confocal microscopy for CD4 and IL-17 colocalization. Our data demonstrated elevated levels of IL-17, TGF-beta, IL-1 beta, IL-6, and IL-23 messenger RNA and protein in diseased tissues as well as the presence of Th17 cells in gingiva from patients with periodontitis. Moreover, IL-17 and the bone resorption factor RANKL were abundantly expressed in the alveolar bone of diseased patients, in contrast to low detection in controls. These results provided strong evidence for the presence of Th17 cells in the sites of chronic inflammation in human periodontal disease.
Resumo:
Ischemia and reperfusion injury (IRI) contributes to the development of chronic interstitial fibrosis/tubular atrophy in renal allograft patients, Cyclooxygenase (COX) 1 and 2 actively participate in acute ischemic injury by activating endothelial cells and inducing oxidative stress. Furthermore, blockade of COX I and 2 has been associated with organ improvement after ischemic damage. The aim of this study was to evaluate the role of COX I and 2 in the development of fibrosis by performing a COX I and 2 blockade immediately before IRI We subjected C57BI/6 male mice to 60 min of unilateral renal pedicle occlusion, Prior to surgery mice were either treated with indomethacin (IMT) at days -1 and 0 or were untreated. Blood and kidney samples were collected 6 wks after IRI. Kidney samples were analyzed by real-time reverse transcription-poly me rase chain reaction for expression of transforming growth factor beta (TGF-beta), monocyte chemoattractant protein 1 (MCP-1), osteopontin (OPN), tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-1 beta, IL-10, heme oxygenose 1 (HO-1), vimentin, connective-tissue growth factor (CTGF), collagen 1, and bone morphogenic protein 7 (BMP-7), To assess tissue fibrosis we performed morphometric analyses and Sirius red staining. We also performed immunohistochemical analysis of anti-actin smooth muscle, Renal function did not significantly differ between groups. Animals pretreated with IMT showed significantly less interstitial fibrosis than nontreated animals. Gene transcript analyses showed decreased expression of TGF-beta, MCP-1,TNF-alpha, IL-1-beta, vimentin, collagen 1, CTGF and IL-10 mRNA (all P < 0.05), Moreover, HO-I mRNA was increased in animals pretreated with IMT (P < 0.05) Conversely, IMT treatment decreased osteopontin expression and enhanced BMP-7 expression, although these levels did rot reach statistical significance when compared with control expression levels, I he blockade of COX 1 and 2 resulted in less tissue fibrosis, which was associated with a decrease in proinflammatory cytokines and enhancement of the protective cellular response.
Resumo:
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.
Resumo:
Introduction: Collagen-degrading matrix metalloproteinases (MMPs) are expressed by odontoblasts and present in dentin. We hypothesized that odontoblasts express other collagen-degrading enzymes such as cysteine cathepsins, and their activity would be present in dentin, because odontoblasts are known to express at least cathepsin D. Effect of transforming growth factor beta (TGF-beta) on cathepsin expression was also analyzed. Methods: Human odontoblasts and pulp tissue were cultured with and without TGF-beta, and cathepsin gene expression was analyzed with DNA microarrays. Dentin cathepsin and MMP activities were analyzed by degradation of respective specific fluorogenic substrates. Results: Both odontoblasts and pulp tissue demonstrated a wide range of cysteine cathepsin expression that gave minor responses to TGF-beta. Cathepsin and MMP activities were observed in all dentin samples, with significant negative correlations in their activities with tooth age. Conclusions: These results demonstrate for the first time the presence of cysteine cathepsins in dentin and suggest their role, along with MMPs, in dentin modification with aging. (J Endod 2010;36:475-481)
Resumo:
Background The continued increase in tuberculosis (TB) rates and the appearance of extremely resistant Mycobacterium tuberculosis strains (XDR-TB) worldwide are some of the great problems of public health. In this context, DNA immunotherapy has been proposed as an effective alternative that could circumvent the limitations of conventional drugs. Nonetheless, the molecular events underlying these therapeutic effects are poorly understood. Methods We characterized the transcriptional signature of lungs from mice infected with M. tuberculosis and treated with heat shock protein 65 as a genetic vaccine (DNAhsp65) combining microarray and real-time polymerase chain reaction analysis. The gene expression data were correlated with the histopathological analysis of lungs. Results The differential modulation of a high number of genes allowed us to distinguish DNAhsp65-treated from nontreated animals (saline and vector-injected mice). Functional analysis of this group of genes suggests that DNAhsp65 therapy could not only boost the T helper (Th)1 immune response, but also could inhibit Th2 cytokines and regulate the intensity of inflammation through fine tuning of gene expression of various genes, including those of interleukin-17, lymphotoxin A, tumour necrosis factor-cl, interleukin-6, transforming growth factor-beta, inducible nitric oxide synthase and Foxp3. In addition, a large number of genes and expressed sequence tags previously unrelated to DNA-therapy were identified. All these findings were well correlated with the histopathological lesions presented in the lungs. Conclusions The effects of DNA therapy are reflected in gene expression modulation; therefore, the genes identified as differentially expressed could be considered as transcriptional biomarkers of DNAhsp65 immunotherapy against TB. The data have important implications for achieving a better understanding of gene-based therapies. Copyright (C) 2008 John Wiley & Sons, Ltd.
Resumo:
One of the early phases that lead to fibrosis progression is inflammation. Once this stage is resolved, fibrosis might be prevented. Bone marrow mononuclear cells (BMMCs) are emerging as a new therapy for several pathologies, including autoimmune diseases, because they enact immunosuppression. In this study we aimed to evaluate the role of BMMC administration in a model of kidney fibrosis induced by an acute injury. C57Bl6 mice were subjected to unilateral severe ischemia by clamping the left renal pedicle for 1 h. BMMCs were isolated from femurs and tibia, and after 6 h of reperfusion, 1 x 10(6) cells were administrated intraperitoneally. At 24 h after surgery, treated animals showed a significant decrease in creatinine and urea levels when compared with untreated animals. Different administration routes were tested. Moreover, interferon (IFN) receptor knockout BMMCs were used, as this receptor is necessary for BMMC activation. Labeled BMMCs were found in ischemic kidney on FACS analysis. This improved outcome was associated with modulation of inflammation in the kidney and systemic modulation, as determined by cytokine expression profiling. Despite non-amelioration of functional parameters, kidney mRNA expression of interleukin (IL)-6 at 6 weeks was lower in BMMC-treated animals, as were levels of collagen 1, connective tissue growth factor (CTGF), transforming growth factor-beta (TGF-beta) and vimentin. Protective molecules, such as IL-10, heme oxygenase 1 (HO-1) and bone morphogenetic 7 (BMP-7), were increased in treated animals after 6 weeks. Moreover, Masson and Picrosirius red staining analyses showed less fibrotic areas in the kidneys of treated animals. Thus, early modulation of inflammation by BMMCs after an ischemic injury leads to reduced fibrosis through modulation of early inflammation.
Resumo:
Mesenchymal stem cells (MSCs) have regenerative properties in acute kidney injury, but their role in chronic kidney diseases is still unknown. More specifically, it is not known whether MSCs halt fibrosis. The purpose of this work was to investigate the role of MSCs in fibrogenesis using a model of chronic renal failure. MSCs were obtained from the tibias and femurs of male Wistar-EPM rats. Female Wistar rats were subjected to the remnant model, and 2 vertical bar x vertical bar 10(5) MSCs were intravenously administrated to each rat every other week for 8 weeks or only once and followed for 12 weeks. SRY gene expression was observed in female rats treated with male MSCs, and immune localization of CD73(+)CD90(+) cells at 8 weeks was also assessed. Serum and urine analyses showed an amelioration of functional parameters in MSC-treated animals at 8 weeks, but not at 12 weeks. Masson`s trichrome and Sirius red staining demonstrated reduced levels of fibrosis in MSC-treated animals. These results were corroborated by reduced vimentin, type I collagen, transforming growth factor beta, fibroblast specific protein 1 (FSP-1), monocyte chemoattractant protein 1, and Smad3 mRNA expression and alpha smooth muscle actin and FSP-1 protein expression. Renal interleukin (IL)-6 and tumor necrosis factor alpha mRNA expression levels were significantly decreased after MSC treatment, whereas IL-4 and IL-10 expression levels were increased. All serum cytokine expression levels were decreased in MSC-treated animals. Taken together, these results suggested that MSC therapy can indeed modulate the inflammatory response that follows the initial phase of a chronic renal injury. The immunosuppressive and remodeling properties of MSCs may be involved in the decreased fibrosis in the kidney. STEM CELLS 2009;27:3063-3073
Resumo:
Transforming growth factor beta (TGF-beta) plays a role both in the induction of Treg and in the differentiation of the IL-17-secreting T cells (Th17) which drive inflammation in experimental autoimmune encephalomyelitis (EAE). We investigated the role that thrombospondin-1 (TSP-1) dependent activation of TGF-beta played in the generation of an encephalitic Th17 response in EAE. Upon immunization with myelin oligodendrocyte glycoprotein peptide (MOG(35-55)), TSP-1 deficient (TSP-1(null)) mice and MOG(35-55) TCR transgenic mice that lack of TSP-1 (2D2.TSP-1(null)) exhibited an attenuated form of EAE, and secreted lower levels of IL-17. Adoptive transfer of in vitro-activated 2D2.TSP-1(null) T cells induced a milder form of EAE, independent of TSP-1 expression in the recipient mice. Furthermore, in vitro studies demonstrated that anti-CD3/anti-CD28 pre-activated CD4+ T cells transiently upregulated latent TGF-beta in a TSP-1 dependent way, and such activation of latent TGF-beta was required for the differentiation of Th17 cells. These results demonstrate that TSP-1 participates in the differentiation of Th17 cells through its ability to activate latent TGF-beta, and enhances the inflammatory response in EAE. (C) 2009 Elsevier Ltd. All rights reserved.
Resumo:
P>Dendritic cells (DCs) play an important role in the clearance of apoptotic cells. The removal of apoptotic cells leads to peripheral tolerance, although their role is still not clear. We show that the uptake of apoptotic thymocytes by DCs converts these cells into tolerogenic DCs resistant to maturation by lipopolysaccharide, modulating the production of interleukin-12 and up-regulating the expression of transforming growth factor-beta(1) latency associated peptide. We also observed that DCs pulsed with apoptotic cells in the allogeneic context were more efficient in the expansion of regulatory T cells (Tregs), and that this expansion requires contact between DCs and the T cell. The Tregs sorted from in vitro culture suppressed the proliferation of splenocytes in vitro in a specific and non-specific manner. In the in vivo model, the transfer of CD4+ CD25- cells to Nude mice induced autoimmunity, with cell infiltrate found in the stomach, colon, liver and kidneys. The co-transfer of CD4+ CD25- and CD4+ CD25+ prevented the presence of cell infiltrates in several organs and increased the total cell count in lymph nodes. Our data indicate that apoptotic cells have an important role in peripheral tolerance via induction of tolerogenic DCs and CD4+ CD25+ Foxp3+ cells that present regulatory functions.
Resumo:
The PKC apoptosis WTI regulator gene, also named prostate apoptosis response-4 (PAR-4), encodes a pro-apoptotic protein that sensitizes cells to numerous apoptotic stimuli. Insulin-like growth factor-1 (IGF-1) and 17 beta-estradiol (E2), two important factors for breast cancer development and progression, have been shown to down-regulate PAR-4 expression and inhibit apoptosis induced by PAR-4 in neuronal cells. In this study, we sought to investigate the mechanisms of regulation of PAR-4 gene expression in MCF-7 cells treated with E2 or IGF-1. E2 (10 nM) and IGF-1 (12.5 nM) each down-regulated PAR-4 expression in MCF-7 cells after 24 h of treatment. The effect of E2 was dependent on ER activation, as demonstrated by an increase in PAR-4 expression when cells were pretreated for 1 h with 1 mu M ICI-182,780 (ICI) before receiving E2 plus ICI. The effect of IGF-1 was abolished by pre-treatment for 1 h with 30 mu M LY294002 (a specific PI3-K inhibitor), and significantly inhibited by 30 mu M SB202190 (a specific p38MAPK inhibitor). We also demonstrated that E2 acts synergistically with IGF-1, resulting in greater down-regulation of PAR-4 mRNA expression compared with E2 or IGF-1 alone. Our results show for the first time that E2 and IGF-1 inhibit PAR-4 gene expression in MCF-7 cells, suggesting that this down-regulation may provide a selective advantage for breast cancer cell survival.
Resumo:
Objective: To assess the association between the depth of trophoblastic penetration into the tubal wall with serum concentrations of vascular endothelial growth factor (VEGF) and beta-hCG and to assess its predictive value. Design: Prospective study. Setting: Tertiary care university hospital. Patient(s): Thirty patients with ampullary pregnancy undergoing salpingectomy were analyzed. Intervention(s): Trophoblastic invasion was histologically classified as stage I when limited to the tubal mucosa, stage II when extending to the muscle layer, and stage III in the case of complete tubal wall infiltration. Main Outcome Measure(s): The relation between depth of trophoblastic infiltration into the tubal wall with VEGF and beta-hCG serum concentrations on the day of surgery. Result(s): An association between the depth of trophoblastic invasion and maternal serum concentrations of VEGF and beta-hCG was observed. VEGF levels of 297.2 pg/mL showed 100.0% sensitivity and 90.0% specificity for stage I, and levels of 440.1 pg/mL showed 81.8% sensitivity and 88.8% specificity for stage III. Beta-hCG levels of 2590.0 mIU/mL showed 88.9% sensitivity and 80.0% specificity for stage I, and levels of 10,827.0 mUI/mL showed 72.7% sensitivity and 88.9% specificity for stage III. Conclusion(s): Maternal serum VEGF and beta-hCG concentrations are associated with depth of trophoblastic penetration into the tubal wall. (Fertil Steril (R) 2010;94:1595-600. (C) 2010 by American Society for Reproductive Medicine.)
Resumo:
Background and objective: Vascular endothelial growth factor (VEGF) is known to increase vascular permeability and promote angiogenesis. It is expressed in most types of pleural effusions. However, the exact role of VEGF in the development of pleural effusions has yet to be determined. The anti-VEGF mAb, bevacizumab, has been used in the treatment of cancer to reduce local angiogenesis and tumour progression. This study describes the acute effects of VEGF blockade on the expression of inflammatory cytokines and pleural fluid accumulation. Methods: One hundred and twelve New Zealand rabbits received intrapleural injections of either talc or silver nitrate. In each group, half the animals received an intravenous injection of bevacizumab, 30 min before the intrapleural agent was administered. Five animals from each subgroup were sacrificed 1, 2, 3, 4 or 7 days after the procedure. Twelve rabbits were used to evaluate vascular permeability using Evans`s blue dye. Pleural fluid volume and cytokines were quantified. Results: Animals pretreated with anti-VEGF antibody showed significant reductions in pleural fluid volumes after talc or silver nitrate injection. IL-8 levels, vascular permeability and macroscopic pleural adhesion scores were also reduced in the groups that received bevacizumab. Conclusions: This study showed that bevacizumab interferes in the acute phase of pleural inflammation induced by silver nitrate or talc, reinforcing the role of VEGF as a key mediator in the production of pleural effusions. The results also suggest that bevacizumab should probably be avoided in patients requiring pleurodesis.
Resumo:
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.
Resumo:
Background: Hepatocyte growth factor (HGF) is overexpressed after acute kidney injury (AKI). The aim of this study was to evaluate the role of endogenous HGF in the progression of the inflammatory response in glycerol-induced AKI (Gly-AKI) in rats. Methods: Renal and systemic HGF expressions were evaluated during the development of Gly-AKI. Subsequently, the blockade of endogenous HGF was analyzed in rats treated with anti-HGF antibody concomitant to glycerol injection. Apoptosis, cell infiltration and chemokine and cytokine profiles were investigated. Results: We detected an early peak of renal and plasma HGF protein expressions 3 h after glycerol injection. The pharmacological blockade of the endogenous HGF exacerbated the renal impairment, the tubular apoptosis, the renal expression of monocyte chemoattractant protein-1 and the macrophage, CD43+, CD4+ and CD8+ T lymphocytes renal infiltration. The analysis of mRNA expressions of Th1 (t-bet, TNF-alpha, IL-1 beta) and Th2 (gata-3, IL-4, IL-10) cytokines showed a Th1-polarized response in Gly-AKI rats that was aggravated with the anti-HGF treatment. Conclusion: Endogenous HGF attenuates the renal inflammatory response, leukocyte infiltration and Th1 polarization after glycerol injection. The control of cellular immune response may partly explain the protective effect of endogenous HGF in the development of Gly-AKI. Copyright (C) 2008 S. Karger AG, Basel
Resumo:
Objective: To evaluate the effects of local administration of epidermal growth factor (EGF) located within liposomes on recruitment of osteoclasts during mechanical force in rats. Materials and Methods: An orthodontic elastic band was inserted between the left upper first and second molars, to move mesially the first molar. Rats were randomly divided into 4 groups (n = 8): EGF (2 ng/mu L) located within liposomes (group 1), liposomes only (group 2), soluble EGF (2 ng/mu L; group 3), or vehicle alone (group 4). The solutions were injected into the region of the root furcation of the left first molar after elastic band insertion. Tooth movement was measured using a plaster model of the maxilla, and the number of osteoclasts recruited at the pressure side of the first molar was histologically evaluated. Results: Intergroup analysis showed that there was no significant difference between group 2 and group 4 (P >.05) and between group 1 and group 3 (P >.05). However, group 1 and group 3 exhibited greater differences in tooth movement than group 2 and group 4 (P <.05). On the other hand, group 1 showed greater tooth movement than groups 2 and 4 with statistical significance (P <.01). The increase in the number of osteoclasts in group 1 was significantly higher than in the other groups (P <.05). Conclusion: Exogenous EGF-liposome administration has an additive effect when compared with soluble EGF on the rate of osteoclast recruitment, producing faster bone resorption and tooth movement.