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Sample records for activated transforming growth

  1. Cells transformed by murine herpesvirus 68 (MHV-68) release compounds with transforming and transformed phenotype suppressing activity resembling growth factors.

    PubMed

    Šupolíková, M; Staňová, A Vojs; Kúdelová, M; Marák, J; Zelník, V; Golais, F

    2015-12-01

    In this study, we investigated the medium of three cell lines transformed with murine herpesvirus 68 (MHV-68) in vitro and in vivo, 68/HDF, 68/NIH3T3, and S11E, for the presence of compounds resembling growth factors of some herpesviruses which have displayed transforming and transformed phenotype suppressing activity in normal and tumor cells. When any of spent medium was added to cell culture we observed the onset of transformed phenotype in baby hamster kidney cells (BHK-21) cells and transformed phenotype suppressing activity in tumor human epithelial cells (HeLa). In media tested, we have identified the presence of putative growth factor related to MHV-68 (MHGF-68). Its bivalent properties have been blocked entirely by antisera against MHV-68 and two monoclonal antibodies against glycoprotein B (gB) of MHV-68 suggesting viral origin of MHGF-68. The results of initial efforts to separate MHGF-68 on FPLC Sephadex G15 column in the absence of salts revealed the loss of its transforming activity but transformed phenotype suppressing activity retained. On the other hand, the use of methanol-water mobile phase on RP-HPLC C18 column allowed separation of MHGF-68 to two compounds. Both separated fractions, had only the transforming activity to normal cells. Further experiments exploring the nature and the structure of hitherto unknown MHGF-68 are now in the progress to characterize its molecular and biological properties.

  2. Control of transforming growth factor-beta activity: latency vs. activation.

    PubMed

    Harpel, J G; Metz, C N; Kojima, S; Rifkin, D B

    1992-01-01

    Transforming growth factor-beta is a pluripotent regulator of cell growth and differentiation. The growth factor is expressed as a latent complex that must be converted to an active form before interacting with its ubiquitous high affinity receptors. This conversion involves the release of the mature growth factor through disruption of the non-covalent interactions with its pro-peptide or latency associated peptide. The mechanisms for this release in vivo have not been fully characterized but appear to be cell specific and might involve processes such as acidification or proteolysis. Although several factors including transcriptional regulation, receptor modulation and scavenging of the active growth factor have been implicated, the critical step controlling the biological effects of transforming growth factor-beta may be the activation of the latent molecule.

  3. Transforming growth factor-beta induces endothelin-1 expression through activation of the Smad signaling pathway.

    PubMed

    Rodríguez-Pascual, Fernando; Reimunde, Francisco Manuel; Redondo-Horcajo, Mariano; Lamas, Santiago

    2004-11-01

    Expression of the endothelin-1 gene is subject to complex regulation by different factors, among which transforming growth factor-beta is one of the most important. We have analyzed the mechanism by which transforming growth factor-beta increases endothelin-1 expression in vascular endothelial cells. Transcriptional activation of the endothelin-1 promoter accounted for the transforming growth factor-beta-induced increase in endothelin-1 mRNA levels. Two DNA elements within the promoter are responsible for this effect: a Smad binding element and a proximal activator protein-1 site. Mutation of both elements abolished transforming growth factor-beta responsiveness. Overexpression of the Smad3 isoform strongly potentiates transforming growth factor-beta- induced endothelin-1 promoter activity in a phosphorylation-dependent manner. These results demonstrate that transforming growth factor-beta induces endothelin-1 expression by a functional cooperation between Smads and activator protein-1 through activation of the Smad signaling pathway.

  4. Differential in vitro phenotype pattern, transforming growth factor-beta(1) activity and mRNA expression of transforming growth factor-beta(1) in Apert osteoblasts.

    PubMed

    Locci, P; Baroni, T; Pezzetti, F; Lilli, C; Marinucci, L; Martinese, D; Becchetti, E; Calvitti, M; Carinci, F

    1999-09-01

    The phenotype of Apert osteoblasts differs from that of normal osteoblasts in the accumulation of macromolecules in the extracellular matrix. Apert osteoblasts increase type I collagen, fibronectin and glycosaminoglycans secretion compared with normal osteoblasts. Because the extracellular matrix macromolecule accumulation is greatly modulated by transforming growth factor-beta(1), we examined the ability of normal and Apert osteoblasts to secrete transforming growth factor-beta(1) by CCL-64 assay and to produce transforming growth factor-beta(1 )by analysis of the mRNA expression of transforming growth factor-beta(1). Northern blot analysis revealed an increased amount of transforming growth factor-beta(1) mRNA expression in Apert osteoblasts compared with normal ones. Moreover, the level of the active transforming growth factor-beta(1) isoform was higher in Apert than in normal media. In pathologic cells, the increase in transforming growth factor-beta(1) gene expression was associated with a parallel increase in the factor secreted into the medium. The level of transforming growth factor-beta(1) was decreased by the addition of basic fibroblast growth factor. Transforming growth factor-beta(1) is controlled temporally and spatially during skeletal tissue development and produces complex stimulatory and inhibitory changes in osteoblast functions. We hypothesise that in vitro differences between normal and Apert osteoblasts may be correlated to different transforming growth factor-beta(1) cascade patterns, probably due to an altered balance between transforming growth factor-beta(1) and basic fibroblast growth factor.

  5. T-cell growth transformation by herpesvirus saimiri is independent of STAT3 activation.

    PubMed

    Heck, Elke; Lengenfelder, Doris; Schmidt, Monika; Müller-Fleckenstein, Ingrid; Fleckenstein, Bernhard; Biesinger, Brigitte; Ensser, Armin

    2005-05-01

    Herpesvirus saimiri (saimirine herpesvirus 2) (HVS), a T-lymphotropic tumor virus, induces lymphoproliferative disease in several species of New World primates. In addition, strains of HVS subgroup C are able to transform T cells of Old World primates, including humans, to permanently growing T-cell lines. In concert with the Stp oncoprotein, the tyrosine kinase-interacting protein (Tip) of HVS C488 is required for T-cell transformation in vitro and lymphoma induction in vivo. Tip was previously shown to interact with the protein tyrosine kinase Lck. Constitutive activation of signal transducers and activators of transcription (STATs) has been associated with oncogenesis and has also been detected in HVS-transformed T-cell lines. Furthermore, Tip contains a putative consensus YXPQ binding motif for the SH2 (src homology 2) domains of STAT1 and STAT3. Tip tyrosine phosphorylation at this site was required for binding of STATs and induction of STAT-dependent transcription. Here we sought to address the relevance of STAT activation for transformation of human T cells by introducing a tyrosine-to-phenylalanine mutation in the YXPQ motif of Tip of HVS C488. Unexpectedly, the recombinant virus was still able to transform human T lymphocytes, but it had lost its capability to activate STAT3 as well as STAT1. This demonstrates that growth transformation by HVS is independent of STAT3 activation.

  6. Immunocytochemical localization of latent transforming growth factor-beta1 activation by stimulated macrophages

    NASA Technical Reports Server (NTRS)

    Chong, H.; Vodovotz, Y.; Cox, G. W.; Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)

    1999-01-01

    Transforming growth factor-beta1 (TGF-beta) is secreted in a latent form consisting of mature TGF-beta noncovalently associated with its amino-terminal propeptide, which is called latency associated peptide (LAP). Biological activity depends upon the release of TGF-beta from the latent complex following extracellular activation, which appears to be the key regulatory mechanism controlling TGF-beta action. We have identified two events associated with latent TGF-beta (LTGF-beta) activation in vivo: increased immunoreactivity of certain antibodies that specifically detect TGF-beta concomitant with decreased immunoreactivity of antibodies to LAP. Macrophages stimulated in vitro with interferon-gamma and lipopolysaccharide reportedly activate LTGF-beta via cell membrane-bound protease activity. We show through dual immunostaining of paraformaldehyde-fixed macrophages that such physiological TGF-beta activation is accompanied by a loss of LAP immunoreactivity with concomitant revelation of TGF-beta epitopes. The induction of TGF-beta immunoreactivity colocalized with immunoreactive betaglycan/RIII in activated macrophages, suggesting that LTGF-beta activation occurs on the cell surface. Confocal microscopy of metabolically active macrophages incubated with antibodies to TGF-beta and betaglycan/RIII prior to fixation supported the localization of activation to the cell surface. The ability to specifically detect and localize LTGF-beta activation provides an important tool for studies of its regulation.

  7. Redox-mediated activation of latent transforming growth factor-beta 1

    NASA Technical Reports Server (NTRS)

    Barcellos-Hoff, M. H.; Dix, T. A.; Chatterjee, A. (Principal Investigator)

    1996-01-01

    Transforming growth factor beta 1 (TGF beta) is a multifunctional cytokine that orchestrates response to injury via ubiquitous cell surface receptors. The biological activity of TGF beta is restrained by its secretion as a latent complex (LTGF beta) such that activation determines the extent of TGF beta activity during physiological and pathological events. TGF beta action has been implicated in a variety of reactive oxygen-mediated tissue processes, particularly inflammation, and in pathologies such as reperfusion injury, rheumatoid arthritis, and atherosclerosis. It was recently shown to be rapidly activated after in vivo radiation exposure, which also generates reactive oxygen species (ROS). In the present studies, the potential for redox-mediated LTGF beta activation was investigated using a cell-free system in which ROS were generated in solution by ionizing radiation or metal ion-catalyzed ascorbate reaction. Irradiation (100 Gray) of recombinant human LTGF beta in solution induced 26% activation compared with that elicited by standard thermal activation. Metal-catalyzed ascorbate oxidation elicited extremely efficient recombinant LTGF beta activation that matched or exceeded thermal activation. The efficiency of ascorbate activation depended on ascorbate concentrations and the presence of transition metal ions. We postulate that oxidation of specific amino acids in the latency-conferring peptide leads to a conformation change in the latent complex that allows release of TGF beta. Oxidative activation offers a novel route for the involvement of TGF beta in tissue processes in which ROS are implicated and endows LTGF beta with the ability to act as a sensor of oxidative stress and, by releasing TGF beta, to function as a signal for orchestrating the response of multiple cell types. LTGF beta redox sensitivity is presumably directed toward recovery of homeostasis; however, oxidation may also be a mechanism of LTGF beta activation that can be deleterious during

  8. Immunohistochemical detection of active transforming growth factor-beta in situ using engineered tissue

    NASA Technical Reports Server (NTRS)

    Barcellos-Hoff, M. H.; Ehrhart, E. J.; Kalia, M.; Jirtle, R.; Flanders, K.; Tsang, M. L.; Chatterjee, A. (Principal Investigator)

    1995-01-01

    The biological activity of transforming growth factor-beta 1 (TGF-beta) is governed by dissociation from its latent complex. Immunohistochemical discrimination of active and latent TGF-beta could provide insight into TGF-beta activation in physiological and pathological processes. However, evaluation of immunoreactivity specificity in situ has been hindered by the lack of tissue in which TGF-beta status is known. To provide in situ analysis of antibodies to differentiate between these functional forms, we used xenografts of human tumor cells modified by transfection to overexpress latent TGF-beta or constitutively active TGF-beta. This comparison revealed that, whereas most antibodies did not differentiate between TGF-beta activation status, the immunoreactivity of some antibodies was activation dependent. Two widely used peptide antibodies to the amino-terminus of TGF-beta, LC(1-30) and CC(1-30) showed marked preferential immunoreactivity with active TGF-beta versus latent TGF-beta in cryosections. However, in formalin-fixed, paraffin-embedded tissue, discrimination of active TGF-beta by CC(1-30) was lost and immunoreactivity was distinctly extracellular, as previously reported for this antibody. Similar processing-dependent extracellular localization was found with a neutralizing antibody raised to recombinant TGF-beta. Antigen retrieval recovered cell-associated immunoreactivity of both antibodies. Two antibodies to peptides 78-109 showed mild to moderate preferential immunoreactivity with active TGF-beta only in paraffin sections. LC(1-30) was the only antibody tested that discriminated active from latent TGF-beta in both frozen and paraffin-embedded tissue. Thus, in situ discrimination of active versus latent TGF-beta depends on both the antibody and tissue preparation. We propose that tissues engineered to express a specific form of a given protein provide a physiological setting in which to evaluate antibody reactivity with specific functional forms of a

  9. Overexpressed homeobox B9 regulates oncogenic activities by transforming growth factor-β1 in gliomas

    SciTech Connect

    Fang, Liping; Xu, Yinghui; Zou, Lijuan

    2014-03-28

    Highlights: • HOXB9 is overexpressed in gliomas. • HOXB9 over expression had shorter survival time than down expression in gliomas. • HOXB9 stimulated the proliferation, migration and sphere formation of glioma cells. • Activation of TGF-β1 contributed to HOXB9-induced oncogenic activities. - Abstract: Glioma is the leading cause of deaths related to tumors in the central nervous system. The mechanisms of gliomagenesis remain elusive to date. Homeobox B9 (HOXB9) has a crucial function in the regulation of gene expression and cell survival, but its functions in glioma formation and development have yet to be elucidated. This study showed that HOXB9 expression in glioma tissues was significantly higher than that in nontumor tissues. Higher HOXB9 expression was also significantly associated with advanced clinical stage in glioma patients. HOXB9 overexpression stimulated the proliferation, migration, and sphere formation of glioma cells, whereas HOXB9 knockdown elicited an opposite effect. HOXB9 overexpression also increased the tumorigenicity of glioma cells in vivo. Moreover, the activation of transforming growth factor-β1 contributed to HOXB9-induced oncogenic activities. HOXB9 could be used as a predictable biomarker to be detected in different pathological and histological subtypes in glioma for diagnosis or prognosis.

  10. Aberrant Transforming Growth Factor-β Activation Recruits Mesenchymal Stem Cells During Prostatic Hyperplasia.

    PubMed

    Wang, Long; Xie, Liang; Tintani, Francis; Xie, Hui; Li, Changjun; Cui, Zhuang; Wan, Mei; Zu, Xiongbing; Qi, Lin; Cao, Xu

    2017-02-01

    Benign prostatic hyperplasia (BPH) is the overgrowth of prostate tissues with high prevalence in older men. BPH pathogenesis is not completely understood, but it is believed to be a result of de novo overgrowth of prostatic stroma. In this study, we show that aberrant activation of transforming growth factor-β (TGF-β) mobilizes mesenchymal/stromal stem cells (MSCs) in circulating blood, which are recruited for the prostatic stromal hyperplasia. Elevated levels of active TGF-β were observed in both a phenylephrine-induced prostatic hyperplasia mouse model and human BPH tissues. Nestin lineage tracing revealed that 39.6% ± 6.3% of fibroblasts and 73.3% ± 4.2% smooth muscle cells were derived from nestin(+) cells in Nestin-Cre, Rosa26-YFP(flox/+) mice. Nestin(+) MSCs were increased in the prostatic hyperplasia mice. Our parabiosis experiment demonstrate that nestin(+) MSCs were mobilized and recruited to the prostatic stroma of wild-type mice and gave rise to the fibroblasts. Moreover, injection of a TGF-β neutralizing antibody (1D11) inhibits mobilization of MSCs, their recruitment to the prostatic stroma and hyperplasia. Importantly, knockout of TβRII in nestin(+) cell lineage ameliorated stromal hyperplasia. Thus, elevated levels of TGF-β-induced mobilization and recruitment of MSCs to the reactive stroma resulting in overgrowth of prostate tissues in BPH and, thus, inhibition of TGF-β activity could be a potential therapy for BPH. Stem Cells Translational Medicine 2017;6:394-404.

  11. Transforming growth factor β-activated kinase 1 transcriptionally suppresses hepatitis B virus replication

    PubMed Central

    Pang, Jinke; Zhang, Geng; Lin, Yong; Xie, Zhanglian; Liu, Hongyan; Tang, Libo; Lu, Mengji; Yan, Ran; Guo, Haitao; Sun, Jian; Hou, Jinlin; Zhang, Xiaoyong

    2017-01-01

    Hepatitis B Virus (HBV) replication in hepatocytes is restricted by the host innate immune system and related intracellular signaling pathways. Transforming growth factor β-activated kinase 1 (TAK1) is a key mediator of toll-like receptors and pro-inflammatory cytokine signaling pathways. Here, we report that silencing or inhibition of endogenous TAK1 in hepatoma cell lines leads to an upregulation of HBV replication, transcription, and antigen expression. In contrast, overexpression of TAK1 significantly suppresses HBV replication, while an enzymatically inactive form of TAK1 exerts no effect. By screening TAK1-associated signaling pathways with inhibitors and siRNAs, we found that the MAPK-JNK pathway was involved in TAK1-mediated HBV suppression. Moreover, TAK1 knockdown or JNK pathway inhibition induced the expression of farnesoid X receptor α, a transcription factor that upregulates HBV transcription. Finally, ectopic expression of TAK1 in a HBV hydrodynamic injection mouse model resulted in lower levels of HBV DNA and antigens in both liver and serum. In conclusion, our data suggest that TAK1 inhibits HBV primarily at viral transcription level through activation of MAPK-JNK pathway, thus TAK1 represents an intrinsic host restriction factor for HBV replication in hepatocytes. PMID:28045080

  12. Inhibition of fatty acid oxidation activates transforming growth factor-beta in cerebrospinal fluid and decreases spontaneous motor activity.

    PubMed

    Fujikawa, Teppei; Fujita, Ryo; Iwaki, Yoko; Matsumura, Shigenobu; Fushiki, Tohru; Inoue, Kazuo

    2010-10-05

    We have previously reported that transforming growth factor (TGF)-beta in the cerebrospinal fluid (CSF) is involved in the mechanism underlying the regulation of spontaneous motor activity (SMA) by the central nervous system after exercise. However, it remained unclear what physiological condition triggers the activation of TGF-beta. We hypothesized that the shortage of energy derived from fatty acid (FA) oxidation observed in the early phase of exercise activated TGF-beta in the CSF. To test this hypothesis, we investigated whether mercaptoacetate (MA), an inhibitor of FA oxidation, could induce an activation of TGF-beta in the CSF and a decrease in SMA. Intraperitoneal (i.p.) administration of MA activated TGF-beta in CSF in rats and depressed SMA; 2-deoxyglucose, an inhibitor of carbohydrate oxidation, on the other hand, depressed SMA but failed to activate CSF TGF-beta. Intracisternal administration of anti-TGF-beta antibody abolished the depressive effect of MA on SMA. We also found that the depression of SMA and the activation of TGF-beta in the CSF by i.p. MA administration were eliminated by vagotomy. Our data suggest that TGF-beta in the CSF is activated by the inhibition of FA oxidation via the vagus nerve and that this subsequently induces depression of SMA.

  13. Activation of transforming growth factor-beta1 and early atherosclerosis in systemic lupus erythematosus.

    PubMed

    Jackson, Michelle; Ahmad, Yasmeen; Bruce, Ian N; Coupes, Beatrice; Brenchley, Paul E C

    2006-01-01

    The efficiency of activating latent transforming growth factor (TGF)-beta1 in systemic lupus erythematosus (SLE) may control the balance between inflammation and fibrosis, modulating the disease phenotype. To test this hypothesis we studied the ability to activate TGF-beta1 in SLE patients and control individuals within the context of inflammatory disease activity, cumulative organ damage and early atherosclerosis. An Activation Index (AI) for TGF-beta1 was determined for 32 patients with SLE and 33 age-matched and sex-matched control individuals by quantifying the increase in active TGF-beta1 under controlled standard conditions. Apoptosis in peripheral blood mononuclear cells was determined by fluorescence-activated cell sorting. Carotid artery intima-media thickness was measured using standard Doppler ultrasound. These measures were compared between patients and control individuals. In an analysis conducted in patients, we assessed the associations of these measures with SLE phenotype, including early atherosclerosis. Both intima-media thickness and TGF-beta1 AI for SLE patients were within the normal range. There was a significant inverse association between TGF-beta1 AI and levels of apoptosis in peripheral blood mononuclear cells after 24 hours in culture for both SLE patients and control individuals. Only in SLE patients was there a significant negative correlation between TGF-beta1 AI and low-density lipoprotein cholesterol (r = -0.404; P = 0.022) and between TGF-beta1 AI and carotid artery intima-media thickness (r = -0.587; P = 0.0004). A low AI was associated with irreversible damage (SLICC [Systemic Lupus International Collaborating Clinics] Damage Index > or = 1) and was inversely correlated with disease duration. Intima-media thickness was significantly linked to total cholesterol (r = 0.371; P = 0.037). To conclude, in SLE low normal TGF-beta1 activation was linked with increased lymphocyte apoptosis, irreversible organ damage, disease duration

  14. Transforming growth factor Beta 1 stimulates profibrotic activities of luteal fibroblasts in cows.

    PubMed

    Maroni, Dulce; Davis, John S

    2012-11-01

    Luteolysis is characterized by angioregression, luteal cell apoptosis, and remodeling of the extracellular matrix characterized by deposition of collagen 1. Transforming growth factor beta 1 (TGFB1) is a potent mediator of wound healing and fibrotic processes through stimulation of the synthesis of extracellular matrix components. We hypothesized that TGFB1 stimulates profibrotic activities of luteal fibroblasts. We examined the actions of TGFB1 on luteal fibroblast proliferation, extracellular matrix production, floating gel contraction, and chemotaxis. Fibroblasts were isolated from the bovine corpus luteum. Western blot analysis showed that luteal fibroblasts expressed collagen 1 and prolyl 4-hydroxylase but did not express markers of endothelial or steroidogenic cells. Treatment of fibroblasts with TGFB1 stimulated the phosphorylation of SMAD2 and SMAD3. [(3)H]thymidine incorporation studies showed that TGFB1 caused concentration-dependent reductions in DNA synthesis in luteal fibroblasts and significantly (P < 0.05) reduced the proliferative effect of FGF2 and fetal calf serum. However, TGFB1 did not reduce the viability of luteal fibroblasts. Treatment of luteal fibroblasts with TGFB1 induced the expression of laminin, collagen 1, and matrix metalloproteinase 1 as determined by Western blot analysis and gelatin zymography of conditioned medium. TGFB1 increased the chemotaxis of luteal fibroblasts toward fibronectin in a transwell system. Furthermore, TGFB1 increased the fibroblast-mediated contraction of floating bovine collagen 1 gels. These results suggest that TGFB1 contributes to the structural regression of the corpus luteum by stimulating luteal fibroblasts to remodel and contract the extracellular matrix.

  15. Mutational activation of BRAF confers sensitivity to transforming growth factor beta inhibitors in human cancer cells

    PubMed Central

    Spender, Lindsay C.; Ferguson, G. John; Liu, Sijia; Cui, Chao; Girotti, Maria Romina; Sibbet, Gary; Higgs, Ellen B.; Shuttleworth, Morven K.; Hamilton, Tom; Lorigan, Paul; Weller, Michael; Vincent, David F.; Sansom, Owen J.; Frame, Margaret; Dijke, Peter ten; Marais, Richard; Inman, Gareth J.

    2016-01-01

    Recent data implicate elevated transforming growth factor-β (TGFβ) signalling in BRAF inhibitor drug-resistance mechanisms, but the potential for targeting TGFβ signalling in cases of advanced melanoma has not been investigated. We show that mutant BRAFV600E confers an intrinsic dependence on TGFβ/TGFβ receptor 1 (TGFBR1) signalling for clonogenicity of murine melanocytes. Pharmacological inhibition of the TGFBR1 blocked the clonogenicity of human mutant BRAF melanoma cells through SMAD4-independent inhibition of mitosis, and also inhibited metastasis in xenografted zebrafish. When investigating the therapeutic potential of combining inhibitors of mutant BRAF and TGFBR1, we noted that unexpectedly, low-dose PLX-4720 (a vemurafenib analogue) promoted proliferation of drug-naïve melanoma cells. Pharmacological or pharmacogenetic inhibition of TGFBR1 blocked growth promotion and phosphorylation of SRC, which is frequently associated with vemurafenib-resistance mechanisms. Importantly, vemurafenib-resistant patient derived cells retained sensitivity to TGFBR1 inhibition, suggesting that TGFBR1 could be targeted therapeutically to combat the development of vemurafenib drug-resistance. PMID:27835901

  16. Glucocorticoid Insensitivity in Virally Infected Airway Epithelial Cells Is Dependent on Transforming Growth Factor-β Activity

    PubMed Central

    Radwan, Asmaa; Keenan, Christine R.; Langenbach, Shenna Y.; Li, Meina; Londrigan, Sarah L.; Gualano, Rosa C.; Stewart, Alastair G.

    2017-01-01

    Asthma and chronic obstructive pulmonary disease (COPD) exacerbations are commonly associated with respiratory syncytial virus (RSV), rhinovirus (RV) and influenza A virus (IAV) infection. The ensuing airway inflammation is resistant to the anti-inflammatory actions of glucocorticoids (GCs). Viral infection elicits transforming growth factor-β (TGF-β) activity, a growth factor we have previously shown to impair GC action in human airway epithelial cells through the activation of activin-like kinase 5 (ALK5), the type 1 receptor of TGF-β. In the current study, we examine the contribution of TGF-β activity to the GC-resistance caused by viral infection. We demonstrate that viral infection of human bronchial epithelial cells with RSV, RV or IAV impairs GC anti-inflammatory action. Poly(I:C), a synthetic analog of double-stranded RNA, also impairs GC activity. Both viral infection and poly(I:C) increase TGF-β expression and activity. Importantly, the GC impairment was attenuated by the selective ALK5 (TGFβRI) inhibitor, SB431542 and prevented by the therapeutic agent, tranilast, which reduced TGF-β activity associated with viral infection. This study shows for the first time that viral-induced glucocorticoid-insensitivity is partially mediated by activation of endogenous TGF-β. PMID:28046097

  17. Constitutively active transforming growth factor β receptor 1 in the mouse ovary promotes tumorigenesis

    PubMed Central

    Gao, Yang; Vincent, David F.; Davis, Anna Jane; Sansom, Owen J.; Bartholin, Laurent; Li, Qinglei

    2016-01-01

    Despite the well-established tumor suppressive role of TGFβ proteins, depletion of key TGFβ signaling components in the mouse ovary does not induce a growth advantage. To define the role of TGFβ signaling in ovarian tumorigenesis, we created a mouse model expressing a constitutively active TGFβ receptor 1 (TGFBR1) in ovarian somatic cells using conditional gain-of-function approach. Remarkably, these mice developed ovarian sex cord-stromal tumors with complete penetrance, leading to reproductive failure and mortality. The tumors expressed multiple granulosa cell markers and caused elevated serum inhibin and estradiol levels, reminiscent of granulosa cell tumors. Consistent with the tumorigenic effect, overactivation of TGFBR1 altered tumor microenvironment by promoting angiogenesis and enhanced ovarian cell proliferation, accompanied by impaired cell differentiation and dysregulated expression of critical genes in ovarian function. By further exploiting complementary genetic models, we substantiated our finding that constitutively active TGFBR1 is a potent oncogenic switch in mouse granulosa cells. In summary, overactivation of TGFBR1 drives gonadal tumor development. The TGFBR1 constitutively active mouse model phenocopies a number of morphological, hormonal, and molecular features of human granulosa cell tumors and are potentially valuable for preclinical testing of targeted therapies to treat granulosa cell tumors, a class of poorly defined ovarian malignancies. PMID:27344183

  18. Transforming growth factor-beta modulates plasminogen activator activity and plasminogen activator inhibitor type-1 expression in human keratinocytes in vitro.

    PubMed

    Wikner, N E; Elder, J T; Persichitte, K A; Mink, P; Clark, R A

    1990-11-01

    Transforming growth factor beta (TGF-beta) is a multifunctional mediator with effects on cellular growth, differentiation, and extracellular matrix (ECM) metabolism. Because TGF-beta stimulates fibronectin expression in cultured human keratinocytes, we wished to determine whether it might also affect ECM degradation through the plasminogen activator (PA)-plasminogen activator inhibitor (PAI) system. Immunofluorescence of human keratinocytes using a monospecific antiserum to type 1 PAI (PAI-1) showed enhanced cellular and ECM staining when they were cultured in the presence of TGF-beta. The antiserum also identified an Mr 50,000 protein in conditioned media that was markedly enhanced by TGF-beta. A corresponding stimulation of PAI-1 mRNA was demonstrated by quantitative RNA blot analysis. Total plasminogen activating activity of conditioned medium was markedly decreased by TGF-beta. Zymography showed this to be at least partially due to decreased secreted urokinase activity. TGF-beta may play an important role in stabilizing the provisional matrix synthesized by keratinocytes in healing wounds.

  19. Synergistic and multidimensional regulation of plasminogen activator inhibitor type 1 expression by transforming growth factor type β and epidermal growth factor

    SciTech Connect

    Song, Xiaoling; Thalacker, F.W.; Nilsen-Hamilton, Marit

    2012-04-06

    The major physiological inhibitor of plasminogen activator, type I plasminogen activator inhibitor (PAI-1), controls blood clotting and tissue remodeling events that involve cell migration. Transforming growth factor type β (TGFβ) and epidermal growth factor (EGF) interact synergistically to increase PAI-1 mRNA and protein levels in human HepG2 and mink Mv1Lu cells. Other growth factors that activate tyrosine kinase receptors can substitute for EGF. EGF and TGFβ regulate PAI-1 by synergistically activating transcription, which is further amplified by a decrease in the rate of mRNA degradation, the latter being regulated only by EGF. The combined effect of transcriptional activation and mRNA stabilization results in a rapid 2-order of magnitude increase in the level of PAI-1. TGFβ also increases the sensitivity of the cells to EGF, thereby recruiting the cooperation of EGF at lower than normally effective concentrations. The contribution of EGF to the regulation of PAI-1 involves the MAPK pathway, and the synergistic interface with the TGFβ pathway is downstream of MEK1/2 and involves phosphorylation of neither ERK1/2 nor Smad2/3. Synergism requires the presence of both Smad and AP-1 recognition sites in the promoter. This work demonstrates the existence of a multidimensional cellular mechanism by which EGF and TGFβ are able to promote large and rapid changes in PAI-1 expression.

  20. Characterization of a novel transcriptionally active domain in the transforming growth factor beta-regulated Smad3 protein.

    PubMed

    Prokova, Vassiliki; Mavridou, Sofia; Papakosta, Paraskevi; Kardassis, Dimitris

    2005-01-01

    Transforming growth factor beta (TGFbeta) regulates transcriptional responses via activation of cytoplasmic effector proteins termed Smads. Following their phosphorylation by the type I TGFbeta receptor, Smads form oligomers and translocate to the nucleus where they activate the transcription of TGFbeta target genes in cooperation with nuclear cofactors and coactivators. In the present study, we have undertaken a deletion analysis of human Smad3 protein in order to characterize domains that are essential for transcriptional activation in mammalian cells. With this analysis, we showed that Smad3 contains two domains with transcriptional activation function: the MH2 domain and a second middle domain that includes the linker region and the first two beta strands of the MH2 domain. Using a protein-protein interaction assay based on biotinylation in vivo, we were able to show that a Smad3 protein bearing an internal deletion in the middle transactivation domain is characterized by normal oligomerization and receptor activation properties. However, this mutant has reduced transactivation capacity on synthetic or natural promoters and is unable to interact physically and functionally with the histone acetyltransferase p/CAF. The loss of interaction with p/CAF or other coactivators could account, at least in part, for the reduced transactivation capacity of this Smad3 mutant. Our data support an essential role of the previously uncharacterized middle region of Smad3 for nuclear functions, such as transcriptional activation and interaction with coactivators.

  1. Induction of apoptosis in bacillus Calmette-Guérin-activated T cells by transforming growth factor-beta.

    PubMed

    Méndez-Samperio, P; Hernández-Garay, M; García-Martínez, E

    2000-06-15

    In view of the critical role played by bacillus Calmette-Guérin (BCG) in the development and functional activation of protective T cells against tuberculosis, it has become important to understand the mechanisms by which cytokines regulate BCG-mediated immune responses. There is evidence that cytokine-mediated suppression of T cell function by mechanisms, including apoptosis, may reduce host resistance in tuberculosis. However, it is unclear whether cytokine-mediated suppression of antigen-responsive T cells through apoptotic mechanisms may be operating during human cellular activation induced by BCG. Here we present evidence, for the first time, that treatment of BCG-activated T cells with transforming growth factor-beta (TGF-beta) induces cellular apoptosis. These results were further supported by the fact that treatment of cells with a blocking mAb directed to TGF-beta significantly inhibited the percentage of apoptosis induced by TGF-beta. Interestingly, TGF-beta-mediated death of BCG-activated T cells in cultures containing interleukin (IL)-12 was observed. Moreover, our results demonstrated the induction of apoptosis by TGF-beta in BCG-activated T cells cultured in the presence of exogenous IL-12. In addition, our data indicated that TGF-beta significantly inhibited both BCG-induced cell growth determined by thymidine uptake and BCG-induced IFN-gamma secretion. Finally, TGF-beta-induced apoptosis in BCG-activated T cells correlated inversely with BCG-induced IFN-gamma secretion. Taken together, these findings indicate that TGF-beta induces apoptosis in human T cells activated with BCG and at the same time suggest that loss of BCG-reactive T cells through apoptotic mechanisms could contribute to an increased susceptibility to Mycobacterium tuberculosis infection.

  2. Transforming growth factor alpha: mutation of aspartic acid 47 and leucine 48 results in different biological activities.

    PubMed Central

    Lazar, E; Watanabe, S; Dalton, S; Sporn, M B

    1988-01-01

    To study the relationship between the primary structure of transforming growth factor alpha (TGF-alpha) and some of its functional properties (competition with epidermal growth factor (EGF) for binding to the EGF receptor and induction of anchorage-independent growth), we introduced single amino acid mutations into the sequence for the fully processed, 50-amino-acid human TGF-alpha. The wild-type and mutant proteins were expressed in a vector by using a yeast alpha mating pheromone promoter. Mutations of two amino acids that are conserved in the family of the EGF-like peptides and are located in the carboxy-terminal part of TGF-alpha resulted in different biological effects. When aspartic acid 47 was mutated to alanine or asparagine, biological activity was retained; in contrast, substitutions of this residue with serine or glutamic acid generated mutants with reduced binding and colony-forming capacities. When leucine 48 was mutated to alanine, a complete loss of binding and colony-forming abilities resulted; mutation of leucine 48 to isoleucine or methionine resulted in very low activities. Our data suggest that these two adjacent conserved amino acids in positions 47 and 48 play different roles in defining the structure and/or biological activity of TGF-alpha and that the carboxy terminus of TGF-alpha is involved in interactions with cellular TGF-alpha receptors. The side chain of leucine 48 appears to be crucial either indirectly in determining the biologically active conformation of TGF-alpha or directly in the molecular recognition of TGF-alpha by its receptor. PMID:3285178

  3. Transforming Growth Factor-Beta and Urokinase-Type Plasminogen Activator: Dangerous Partners in Tumorigenesis—Implications in Skin Cancer

    PubMed Central

    Santibanez, Juan F.

    2013-01-01

    Transforming growth factor-beta (TGF-β) is a pleiotropic factor, with several different roles in health and disease. TGF-β has been postulated as a dual factor in tumor progression, since it represses epithelial tumor development in early stages, whereas it stimulates tumor progression in advanced stages. During tumorigenesis, cancer cells acquire the capacity to migrate and invade surrounding tissues and to metastasize different organs. The urokinase-type plasminogen activator (uPA) system, comprising uPA, the uPA cell surface receptor, and plasminogen-plasmin, is involved in the proteolytic degradation of the extracellular matrix and regulates key cellular events by activating intracellular signal pathways, which together allow cancer cells to survive, thus, enhancing cell malignance during tumor progression. Due to their importance, uPA and its receptor are tightly transcriptionally regulated in normal development, but are deregulated in cancer, when their activity and expression are related to further development of cancer. TGF-β regulates uPA expression in cancer cells, while uPA, by plasminogen activation, may activate the secreted latent TGF-β, thus, producing a pernicious cycle which contributes to the enhancement of tumor progression. Here we review the specific roles and the interplay between TGF-β and uPA system in cancer cells and their implication in skin cancer. PMID:23984088

  4. High glucose increases Cdk5 activity in podocytes via transforming growth factor-β1 signaling pathway

    SciTech Connect

    Zhang, Yue; Li, Hongbo; Hao, Jun; Zhou, Yi; Liu, Wei

    2014-08-15

    Podocytes are highly specialized and terminally differentiated glomerular cells that play a vital role in the development and progression of diabetic nephropathy (DN). Cyclin-dependent kinase 5 (Cdk5), who is an atypical but essential member of the Cdk family of proline-directed serine/threonine kinases, has been shown as a key regulator of podocyte differentiation, proliferation and morphology. Our previous studies demonstrated that the expression of Cdk5 was significantly increased in podocytes of diabetic rats, and was closely related with podocyte injury of DN. However, the mechanisms of how expression and activity of Cdk5 are regulated under the high glucose environment have not yet been fully elucidated. In this study, we showed that high glucose up-regulated the expression of Cdk5 and its co-activator p35 with a concomitant increase in Cdk5 kinase activity in conditionally immortalized mouse podocytes in vitro. When exposed to 30 mM glucose, transforming growth factor-β1 (TGF-β1) was activated. Most importantly, we found that SB431542, the Tgfbr1 inhibitor, significantly decreased the expression of Cdk5 and p35 and Cdk5 kinase activity in high glucose-treated podocytes. Moreover, high glucose increased the expression of early growth response-1 (Egr-1) via TGF-β1-ERK1/2 pathway in podocytes and inhibition of Egr-1 by siRNA decreased p35 expression and Cdk5 kinase activity. Furthermore, inhibition of Cdk5 kinase activity effectively alleviated podocyte apoptosis induced by high glucose or TGF-β1. Thus, the TGF-β1-ERK1/2-Egr-1 signaling pathway may regulate the p35 expression and Cdk5 kinase activity in high glucose-treated podocytes, which contributes to podocyte injury of DN. - Highlights: • HG up-regulated the expression of Cdk5 and p35, and Cdk5 activity in podocytes. • HG activated TGF-β1 pathway and SB431542 inhibited Cdk5 expression and activity. • HG increased the expression of Egr-1 via TGF-β1-ERK1/2 pathway. • Inhibition of Egr-1

  5. Cancer cells. 3: Growth factors and transformation

    SciTech Connect

    Feramisco, J.; Ozanne, B.; Stiles, C.

    1985-01-01

    This book contains over 50 papers. Some of the titles are: Structure of Human Epidermal Growth Factor and Expression of Normal and Variant mRNAs in Epdermoid Carcinoma Cells; Tyrosine Kinase Activity Associated with the v-erb-B Gene Product; Cloning and Characterization of Human Epidermal Growth Factor-Receptor Gene Sequences in A431 Carcinoma Cells; Anti-oncogenes and the Suppression of Tumor Formation; and Normal Human sis/PDGF-2 Gene Expression Induces Cellular Transformation.

  6. Constitutive activation of transforming growth factor Beta receptor 1 in the mouse uterus impairs uterine morphology and function.

    PubMed

    Gao, Yang; Duran, Samantha; Lydon, John P; DeMayo, Francesco J; Burghardt, Robert C; Bayless, Kayla J; Bartholin, Laurent; Li, Qinglei

    2015-02-01

    Despite increasing evidence pointing to the essential involvement of the transforming growth factor beta (TGFB) superfamily in reproduction, a definitive role of TGFB signaling in the uterus remains to be unveiled. In this study, we generated a gain-of-function mouse model harboring a constitutively active (CA) TGFB receptor 1 (TGFBR1), the expression of which was conditionally induced by the progesterone receptor (Pgr)-Cre recombinase. Overactivation of TGFB signaling was verified by enhanced phosphorylation of SMAD2 and increased expression of TGFB target genes in the uterus. TGFBR1 Pgr-Cre CA mice were sterile. Histological, cellular, and molecular analyses demonstrated that constitutive activation of TGFBR1 in the mouse uterus promoted formation of hypermuscled uteri. Accompanying this phenotype was the upregulation of a battery of smooth muscle genes in the uterus. Furthermore, TGFB ligands activated SMAD2/3 and stimulated the expression of a smooth muscle maker gene, alpha smooth muscle actin (ACTA2), in human uterine smooth muscle cells. Immunofluorescence microscopy identified a marked reduction of uterine glands in TGFBR1 Pgr-Cre CA mice within the endometrial compartment that contained myofibroblast-like cells. Thus, constitutive activation of TGFBR1 in the mouse uterus caused defects in uterine morphology and function, as evidenced by abnormal myometrial structure, dramatically reduced uterine glands, and impaired uterine decidualization. These results underscore the importance of a precisely controlled TGFB signaling system in establishing a uterine microenvironment conducive to normal development and function.

  7. Transforming Growth Factor-β: Activation by Neuraminidase and Role in Highly Pathogenic H5N1 Influenza Pathogenesis

    PubMed Central

    Moser, Lindsey A.; O'Brien, Kevin B.; Cline, Troy D.; Jones, Jeremy C.; Tumpey, Terrence M.; Katz, Jacqueline M.; Kelley, Laura A.; Gauldie, Jack; Schultz-Cherry, Stacey

    2010-01-01

    Transforming growth factor-beta (TGF-β), a multifunctional cytokine regulating several immunologic processes, is expressed by virtually all cells as a biologically inactive molecule termed latent TGF-β (LTGF-β). We have previously shown that TGF-β activity increases during influenza virus infection in mice and suggested that the neuraminidase (NA) protein mediates this activation. In the current study, we determined the mechanism of activation of LTGF-β by NA from the influenza virus A/Gray Teal/Australia/2/1979 by mobility shift and enzyme inhibition assays. We also investigated whether exogenous TGF-β administered via a replication-deficient adenovirus vector provides protection from H5N1 influenza pathogenesis and whether depletion of TGF-β during virus infection increases morbidity in mice. We found that both the influenza and bacterial NA activate LTGF-β by removing sialic acid motifs from LTGF-β, each NA being specific for the sialic acid linkages cleaved. Further, NA likely activates LTGF-β primarily via its enzymatic activity, but proteases might also play a role in this process. Several influenza A virus subtypes (H1N1, H1N2, H3N2, H5N9, H6N1, and H7N3) except the highly pathogenic H5N1 strains activated LTGF-β in vitro and in vivo. Addition of exogenous TGF-β to H5N1 influenza virus–infected mice delayed mortality and reduced viral titers whereas neutralization of TGF-β during H5N1 and pandemic 2009 H1N1 infection increased morbidity. Together, these data show that microbe-associated NAs can directly activate LTGF-β and that TGF-β plays a pivotal role protecting the host from influenza pathogenesis. PMID:20949074

  8. Alteration of N-glycoproteins/N-glycosites in human hepatic stellate cells activated with transforming growth factor-β1.

    PubMed

    Qin, Y; Wang, Q; Zhong, Y; Zhao, F; Wu, F; Wang, Y; Ma, T; Liu, C; Bian, H; Li, Z

    2016-03-20

    Proteins N-glycosylation is significantly increased in the activated human hepatic stellate cells (HSCs) stimulated by transforming growth factor-β1 (TGF-β1) compared to the quiescent HSCs according to our previous study. However, little is known about the alteration of N-glycoprotein profiles in the activated HSCs. Profiles of N-glycopeptides / N-glycoproteins / N-glycosites in LX-2 cells, with and without activation by TGF-β1, were identified and compared using hydrazide chemistry enrichment coupled with liquid chromatography - mass spectrometry analysis. Western blot and immunohistochemistry were further used for validation. A total of 103 non-redundant N-glycopeptides, with 107 glycosylation sites from 86 N-glycoproteins, were identified in activated and quiescent LX-2 cells respectively. Among these, 23 proteins were known N-glycoproteins, and 58 were newly identified N-glycoproteins. In addition, 43 proteins (e.g., pigment epithelium-derived factor and clathrin heavy chain 1) were solely identified or up-regulated in the activated LX-2 cells, which participated in focal adhesion and glycosaminoglycan degradation pathways and were involved in interaction clusters of cytoskeletal proteins (e.g., myosin light chains and keratins). The increased expression of glucosamine (N-acetyl)-6-sulfatase and phospholipase C beta 2 and the decreased expression of zinc finger and BTB domain-containing protein 1 were validated in the activated compared to the quiescent LX-2 cells. In conclusion, increased expression of N-glycoproteins and N-glycosites play important roles in cellular contractility, signal transduction, and responses to stimuli in the activated HSCs, which might provide useful information for discovering novel molecular mechanism of HSC activation and therapeutic targets in liver fibrosis.

  9. Transforming growth factor-β promotes ‘death by neglect’ in post-activated human T cells

    PubMed Central

    Sillett, H K; Cruickshank, S M; Southgate, J; Trejdosiewicz, L K

    2001-01-01

    Transforming growth factor-β (TGF-β) is central to the wound repair processes that follow local trauma and inflammation. In order to mimic the early events of wound-healing, we studied the effects of TGF-β on mitogen-stimulated peripheral blood cells. TGF-β added at the initiation of mitogenesis did not significantly alter T-cell activation, proliferation, CD45 isoform switching, or activation-induced cell death. By contrast, TGF-β added 72 hr post-activation (or later) enhanced the cumulative increase in apoptotic T cells. TGF-β had no effect on mitogen-induced up-regulation of Fas (CD95) or Fas ligand and did not enhance killing of the Fas-sensitive Jurkat cell line by activated T cells. Furthermore, TGF-β had no direct effect on levels of mRNA for members of the bcl family (bcl-X, bfl-1, bik, bak, bax, bcl-2 and mcl-1). These findings suggest that TGF-β does not directly induce apoptosis via the Fas system or by direct effects on bcl proteins. However, interleukin-2, which can ‘rescue’ lymphocytes from spontaneous apoptosis due to cytokine deprivation, abolished the pro-apoptotic effects of TGF-β on post-activated T cells, thus demonstrating that TGF-β increases the cytokine-dependence of T cells for survival. We propose a novel role for TGF-β in the suppression of inflammation by promoting the elimination of post-activated T cells once the initiating stimulus has been resolved. PMID:11298829

  10. Latent transforming growth factor beta1 activation in situ: quantitative and functional evidence after low-dose gamma-irradiation

    NASA Technical Reports Server (NTRS)

    Ehrhart, E. J.; Segarini, P.; Tsang, M. L.; Carroll, A. G.; Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)

    1997-01-01

    The biological activity of transforming growth factor beta1 (TGF-beta) is controlled by its secretion as a latent complex in which it is noncovalently associated with latency-associated peptide (LAP). Activation is the extracellular process in which TGF-beta is released from LAP, and is considered to be a primary regulatory control. We recently reported rapid and persistent changes in TGF-beta immunoreactivity in conjunction with extracellular matrix remodeling in gamma-irradiated mouse mammary gland. Our hypothesis is that these specific changes in immunoreactivity are indicative of latent TGF-beta activation. In the present study, we determined the radiation dose response and tested whether a functional relationship exists between radiation-induced TGF-beta and collagen type III remodeling. After radiation exposures as low as 0.1 Gy, we detected increased TGF-beta immunoreactivity in the mammary epithelium concomitant with decreased LAP immunostaining, which are events consistent with activation. Quantitative image analysis demonstrated a significant (P=0.0005) response at 0.1 Gy without an apparent threshold and a linear dose response to 5 Gy. However, in the adipose stroma, loss of LAP demonstrated a qualitative threshold at 0.5 Gy. Loss of LAP paralleled induction of collagen III immunoreactivity in this tissue compartment. We tested whether TGF-beta mediates collagen III expression by treating animals with TGF-beta panspecific monoclonal antibody, 1D11.16, administered i.p. shortly before irradiation. Radiation-induced collagen III staining in the adipose stroma was blocked in an antibody dose-dependent manner, which persisted through 7 days postirradiation. RNase protection assay revealed that radiation-induced elevation of total gland collagen III mRNA was also blocked by neutralizing antibody treatment. These data provide functional confirmation of the hypothesis that radiation exposure leads to latent TGF-beta activation, support our interpretation of the

  11. Sequential analysis of myofibroblast differentiation and transforming growth factor-β1/Smad pathway activation in murine pulmonary fibrosis.

    PubMed

    Usuki, Jiro; Matsuda, Kuniko; Azuma, Arata; Kudoh, Shoji; Gemma, Akihiko

    2012-01-01

    Myofibroblasts play a critical role in tissue fibrosis. However, the intracellular signaling pathways in myofibroblast differentiation are poorly understood. Here, we studied the relationship between transforming growth factor-β (TGF-β)/Smad pathway activation and myofibroblast differentiation in both in vivo and in vitro experiments. In murine bleomycin-induced pulmonary fibrosis, nuclear localization of phosphorylated Smad2/3 (p-Smad2/3) was observed in pulmonary fibrotic lesions 7 days after bleomycin injection, whereas α-smooth muscle actin (ASMA)-positive myofibroblasts appeared in the lesions at 14 days, when the cytoplasmic localization of p-Smad2/3 was observed. We also compared the effects of TGF-β1 on myofibroblast differentiation and on type I collagen expression in a murine lung fibroblast cell line (MLg2908). TGF-β1 induced rapid expression of p-Smad2/3 in nuclei, after which ASMA organization in the cytoplasm of fibroblasts was observed. However, TGF-β1 produced no effect on the quantity of ASMA, either in mRNA levels or protein levels, even after the phosphorylation of Smad2/3. In contrast, TGF-β1 upregulated the expression of type I collagen mRNA. These findings suggest that in pulmonary fibrosis the molecular mechanism of myofibroblast differentiation is complex and that the difference between ASMA expression and type I collagen expression is mediated by the TGF-β/Smad pathway.

  12. Vascular smooth muscle cells from injured rat aortas display elevated matrix production associated with transforming growth factor-beta activity.

    PubMed Central

    Rasmussen, L. M.; Wolf, Y. G.; Ruoslahti, E.

    1995-01-01

    The arterial response to injury is characterized by a short period of increased proliferation and migration of vascular smooth muscle cells, followed by an extended period of extracellular matrix accumulation in the intima. Transforming growth factor-beta (TGF-beta) has been implicated as a causative factor in the formation of extracellular matrix in this process, which leads to progressive thickening of the intima, known as intimal hyperplasia. In vitro analysis of vascular smooth muscle cells harvested from normal rat aortas and from aortas injured 14 days earlier showed that both types of cells attached equally well to culture dishes but that the initial spreading of the cells was increased in cells derived from injured vessels. Cells from the injured arteries produced more fibronectin and proteoglycans into the culture medium than the cells from normal arteries and contained more TGF-beta 1 mRNA. TGF-beta 1 increased proteoglycan synthesis by normal smooth muscle cells, and the presence of a neutralizing anti-TGF-beta 1 antibody reduced proteoglycan synthesis by the cells from injured arteries in culture. Fibronectin synthesis was not altered by these treatments. These results indicate that the accumulation of extracellular matrix components in neointimal lesions is at least partially caused by autocrine TGF-beta activity in vascular smooth muscle cells. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7573349

  13. Specifically Formed Corona on Silica Nanoparticles Enhances Transforming Growth Factor β1 Activity in Triggering Lung Fibrosis.

    PubMed

    Wang, Zhenzhen; Wang, Chunming; Liu, Shang; He, Wei; Wang, Lintao; Gan, JingJing; Huang, Zhen; Wang, Zhenheng; Wei, Haoyang; Zhang, Junfeng; Dong, Lei

    2017-02-28

    A corona is a layer of macromolecules formed on a nanoparticle surface in vivo. It can substantially change the biological identity of nanomaterials and possibly trigger adverse responses from the body tissues. Dissecting the role of the corona in the development of a particular disease may provide profound insights for understanding toxicity of nanomaterials in general. In our present study, we explored the capability of different silica nanoparticles (SiNPs) to induce silicosis in the mouse lung and analyzed the composition of coronas formed on these particles. We found that SiNPs of certain size and surface chemistry could specifically recruit transforming growth factor β1 (TGF-β1) into their corona, which subsequently induces the development of lung fibrosis. Once embedded into the corona on SiNPs, TGF-β1 was remarkably more stable than in its free form, and its fibrosis-triggering activity was significantly prolonged. Our study meaningfully demonstrates that a specific corona component on a certain nanoparticle could initiate a particular pathogenic process in a clinically relevant disease model. Our findings may shed light on the understanding of molecular mechanisms of human health risks correlated with exposure to small-scale substances.

  14. Signaling activity of transforming growth factor beta type II receptors lacking specific domains in the cytoplasmic region.

    PubMed Central

    Wieser, R; Attisano, L; Wrana, J L; Massagué, J

    1993-01-01

    The transforming growth factor beta (TGF-beta) type II receptor (T beta R-II) is a transmembrane serine/threonine kinase that contains two inserts in the kinase region and a serine/threonine-rich C-terminal extension. T beta R-II is required for TGF-beta binding to the type I receptor, with which it forms a heteromeric receptor complex, and its kinase activity is required for signaling by this complex. We investigated the role of various cytoplasmic regions in T beta R-II by altering or deleting these regions and determining the signaling activity of the resulting products in cell lines made resistant to TGF-beta by inactivation of the endogenous T beta R-II. TGF-beta binding to receptor I and responsiveness to TGF-beta in these cells can be restored by transfection of wild-type T beta R-II. Using this system, we show that the kinase insert 1 and the C-terminal tail of T beta R-II, in contrast to the corresponding regions in most tyrosine kinase receptors, are not essential to specify ligand-induced responses. Insert 2 is necessary to support the catalytic activity of the receptor kinase, and its deletion yields a receptor that is unable to mediate any of the responses tested. However, substitution of this insert with insert 2 from the activin receptor, ActR-IIB, does not diminish the ability of T beta R-II to elicit these responses. A truncated T beta R-II lacking the cytoplasmic domain still binds TGF-beta, supports ligand binding to receptor I, and forms a complex with this receptor. However, TGF-beta binding to receptor I facilitated by this truncated T beta R-II fails to inhibit cell proliferation, activate extracellular matrix protein production, or activate transcription from a promoter containing TGF-beta-responsive elements. We conclude that the transcriptional and antiproliferative responses to TGF-beta require both components of a heteromeric receptor complex that differs from tyrosine kinase receptors in its mode of signaling. Images PMID:8246946

  15. Epithelial to mesenchymal transition in arsenic-transformed cells promotes angiogenesis through activating β-catenin–vascular endothelial growth factor pathway

    SciTech Connect

    Wang, Zhishan; Humphries, Brock; Xiao, Hua; Jiang, Yiguo; Yang, Chengfeng

    2013-08-15

    Arsenic exposure represents a major health concern increasing cancer risks, yet the mechanism of arsenic carcinogenesis has not been elucidated. We and others recently reported that cell malignant transformation by arsenic is accompanied by epithelial to mesenchymal transition (EMT). However, the role of EMT in arsenic carcinogenesis is not well understood. Although previous studies showed that short term exposure of endothelial cells to arsenic stimulated angiogenesis, it remains to be determined whether cells that were malignantly transformed by long term arsenic exposure have a pro-angiogenic effect. The objective of this study was to investigate the effect of arsenic-transformed human bronchial epithelial cells that underwent EMT on angiogenesis and the underlying mechanism. It was found that the conditioned medium from arsenic-transformed cells strongly stimulated tube formation by human umbilical vein endothelial cells (HUVECs). Moreover, enhanced angiogenesis was detected in mouse xenograft tumor tissues resulting from inoculation of arsenic-transformed cells. Mechanistic studies revealed that β-catenin was activated in arsenic-transformed cells up-regulating its target gene expression including angiogenic-stimulating vascular endothelial growth factor (VEGF). Stably expressing microRNA-200b in arsenic-transformed cells that reversed EMT inhibited β-catenin activation, decreased VEGF expression and reduced tube formation by HUVECs. SiRNA knockdown β-catenin decreased VEGF expression. Adding a VEGF neutralizing antibody into the conditioned medium from arsenic-transformed cells impaired tube formation by HUVECs. Reverse transcriptase-PCR analysis revealed that the mRNA levels of canonical Wnt ligands were not increased in arsenic-transformed cells. These findings suggest that EMT in arsenic-transformed cells promotes angiogenesis through activating β-catenin–VEGF pathway. - Highlights: • Arsenic-transformed cells that underwent EMT displayed a pro

  16. Activities: Geometric Transformations. Part 2.

    ERIC Educational Resources Information Center

    Eddins, Susan K.; And Others

    1994-01-01

    Presents a lesson that connects basic transformational concepts with transformations on a Cartesian-coordinate system, culminating with the application of matrix operations to perform geometric transformations. Includes reproducible student worksheets and assessment activities. (MKR)

  17. Transforming growth factor beta regulates thyroid growth. Role in the pathogenesis of nontoxic goiter.

    PubMed Central

    Grubeck-Loebenstein, B; Buchan, G; Sadeghi, R; Kissonerghis, M; Londei, M; Turner, M; Pirich, K; Roka, R; Niederle, B; Kassal, H

    1989-01-01

    The production and growth regulatory activity of transforming growth factor beta were studied in human thyroid tissue. As estimated by its mRNA expression in fresh tissue samples, transforming growth factor beta was produced in normal and in diseased thyroid glands. Transforming growth factor beta mRNA was mainly produced by thyroid follicular cells and in lesser quantities by thyroid infiltrating mononuclear cells. The concentrations of transforming growth factor beta mRNA were lower in iodine-deficient nontoxic goiter than in Graves' disease and normal thyroid tissue. Transforming growth factor beta protein secretion by cultured thyroid follicular cells was also low in nontoxic goiter, but could be increased by addition of sodium iodide (10 microM) to the culture medium. Recombinant transforming growth factor beta did not affect basal tritiated thymidine incorporation in cultured thyroid follicular cells, but inhibited, at a concentration of 10 ng/ml, the growth stimulatory influence of insulin-like growth factor I, epidermal growth factor, transforming growth factor alpha, TSH, and partly that of normal human serum on cultured thyroid follicular cells. This inhibition was greater in Graves' disease than in nontoxic goiter. These results suggest that transforming growth factor beta may act as an autocrine growth inhibitor on thyroid follicular cells. Decreased transforming growth factor beta production and decreased responsiveness to transforming growth factor beta may be cofactors in the pathogenesis of iodine-deficient nontoxic goiter. Images PMID:2921318

  18. The activation sequence of thrombospondin-1 interacts with the latency-associated peptide to regulate activation of latent transforming growth factor-beta.

    PubMed

    Ribeiro, S M; Poczatek, M; Schultz-Cherry, S; Villain, M; Murphy-Ullrich, J E

    1999-05-07

    One of the primary points of regulation of transforming growth factor-beta (TGF-beta) activity is control of its conversion from the latent precursor to the biologically active form. We have identified thrombospondin-1 as a major physiological regulator of latent TGF-beta activation. Activation is dependent on the interaction of a specific sequence in thrombospondin-1 (K412RFK415) with the latent TGF-beta complex. Platelet thrombospon-din-1 has TGF-beta activity and immunoreactive mature TGF-beta associated with it. We now report that the latency-associated peptide (LAP) of the latent TGF-beta complex also interacts with thrombospondin-1 as part of a biologically active complex. Thrombospondin.LAP complex formation involves the activation sequence of thrombospondin-1 (KRFK) and a sequence (LSKL) near the amino terminus of LAP that is conserved in TGF-beta1-5. The interactions of LAP with thrombospondin-1 through the LSKL and KRFK sequences are important for thrombospondin-mediated activation of latent TGF-beta since LSKL peptides can competitively inhibit latent TGF-beta activation by thrombospondin or KRFK-containing peptides. In addition, the association of LAP with thrombospondin-1 may function to prevent the re-formation of an inactive LAP.TGF-beta complex since thrombospondin-bound LAP no longer confers latency on active TGF-beta. The mechanism of TGF-beta activation by thrombospondin-1 appears to be conserved among TGF-beta isoforms as latent TGF-beta2 can also be activated by thrombospondin-1 or KRFK peptides in a manner that is sensitive to inhibition by LSKL peptides.

  19. Effects of transforming growth factor-[beta] and budesonide on mitogen-activated protein kinase activation and apoptosis in airway epithelial cells.

    PubMed

    Pelaia, Girolamo; Cuda, Giovanni; Vatrella, Alessandro; Fratto, Donatella; Grembiale, Rosa D; Tagliaferri, Pierosandro; Maselli, Rosario; Costanzo, Francesco S; Marsico, Serafino A

    2003-07-01

    Airway epithelial cells play a central role in the inflammatory, apoptotic, and remodeling processes associated with asthma. Within this context, a key function is exerted by transforming growth factor-beta (TGF-beta), whose biological effects are mediated at least in part by mitogen-activated protein kinases (MAPKs). The aim of our study was to investigate, in primary cultures of human bronchial epithelial cells (HBEC), the effects of TGF-beta (10 ng/ml) on both MAPK activation and apoptosis, in the presence or absence of a pretreatment with budesonide (10-8 M). MAPK activation was detected by Western blotting, using anti-phospho-MAPK monoclonal antibodies, which specifically recognize the phosphorylated, active forms of these enzymes. Apoptosis was assayed by caspase-3 activation and fluorescence microscopy, using annexin-V (An-V) and propidium iodide (PI) as markers of cell death. Our results show that TGF-beta induced a marked ( reverse similar 9-fold) increase in p38 MAPK phosphorylation, and also dramatically enhanced cell death, which was completely prevented by specific MAPK inhibitors. Both MAPK activation and apoptosis were effectively inhibited by budesonide (BUD), thereby suggesting that the powerful antiapoptotic action of inhaled glucocorticoids may be very important for their protective role against epithelial injury, which represents a key pathogenic event in asthma.

  20. High glucose concentration induces the overexpression of transforming growth factor-beta through the activation of a platelet-derived growth factor loop in human mesangial cells.

    PubMed Central

    Di Paolo, S.; Gesualdo, L.; Ranieri, E.; Grandaliano, G.; Schena, F. P.

    1996-01-01

    High glucose concentration has been shown to induce the overexpression of transforming growth factor (TGF)-beta 1 mRNA and protein in different cell types, including murine mesangial cells, thus possibly accounting for the expansion of mesangial extracellular matrix observed in diabetic glomerulopathy. In the present study, we evaluated platelet-derived growth factor (PDGF) B-chain and PDGF-beta receptor gene expression in human mesangial cells (HMCs) exposed to different concentrations of glucose and then sought a possible relationship between a PDGF loop and the modulation of TGF-beta 1 expression. HMC [3H]thymidine incorporation was upregulated by 30 mmol/L glucose (HG) up to 24 hours, whereas it was significantly inhibited at later time points. Neutralizing antibodies to PDGF BB abolished the biphasic response to HG, whereas anti-TGF-beta antibodies reversed only the late inhibitory effect of hyperglycemic medium. HG induced an early and persistent increase of PDGF B-chain gene expression, as evaluated by reverse transcriptase polymerase chain reaction, whereas PDGF-beta receptor mRNA increased by twofold after 6 hours, thereafter declining at levels 70% lower than in controls after 24 hours. 125I-Labeled PDGF BB binding studies in HMCs exposed to HG for 24 hours confirmed the decrease of PDGF-beta receptor expression. TGF-beta 1-specific transcripts showed 43 and 78% increases after 24 and 48 hours of incubation in HG, respectively, which was markedly diminished by anti-PDGF BB neutralizing antibodies or suramin. We conclude that HG induces an early activation of a PDGF loop that, in turn, causes an increase of TGF-beta 1 gene expression, thus modulating both HMC proliferation and mesangial matrix production. Images Figure 2 Figure 3 Figure 4 Figure 5 PMID:8952542

  1. The carboxy-terminal domains of erbB-2 and epidermal growth factor receptor exert different regulatory effects on intrinsic receptor tyrosine kinase function and transforming activity.

    PubMed Central

    Di Fiore, P P; Segatto, O; Lonardo, F; Fazioli, F; Pierce, J H; Aaronson, S A

    1990-01-01

    The erbB-2 gene product, gp185erbB-2, displays a potent transforming effect when overexpressed in NIH 3T3 cells. In addition, it possesses constitutively high levels of tyrosine kinase activity in the absence of exogenously added ligand. In this study, we demonstrate that its carboxy-terminal domain exerts an enhancing effect on erbB-2 kinase and transforming activities. A premature termination mutant of the erbB-2 protein, lacking the entire carboxy-terminal domain (erbB-2 delta 1050), showed a 40-fold reduction in transforming ability and a lowered in vivo kinase activity for intracellular substrates. When the carboxy-terminal domain of erbB-2 was substituted for its analogous region in the epidermal growth factor receptor (EGFR) (EGFR/erbB-2COOH chimera), it conferred erbB-2-like properties to the EGFR, including transforming ability in the absence of epidermal growth factor, elevated constitutive autokinase activity in vivo and in vitro, and constitutive ability to phosphorylate phospholipase C-gamma. Conversely, a chimeric erbB-2 molecule bearing an EGFR carboxy-terminal domain (erbB-2/EGFRCOOH chimera) showed reduced transforming and kinase activity with respect to the wild-type erbB-2 and was only slightly more efficient than the erbB-2 delta 1050 mutant. Thus, we conclude that the carboxy-terminal domains of erbB-2 and EGFR exert different regulatory effects on receptor kinase function and biological activity. The up regulation of gp185erbB-2 enzymatic activity exerted by its carboxy-terminal domain can explain, at least in part, its constitutive level of kinase activity. Images PMID:2188097

  2. Polyubiquitination of Transforming Growth Factor β-activated Kinase 1 (TAK1) at Lysine 562 Residue Regulates TLR4-mediated JNK and p38 MAPK Activation

    PubMed Central

    Chen, I-Ting; Hsu, Pang-Hung; Hsu, Wan-Ching; Chen, Nien-Jung; Tseng, Ping-Hui

    2015-01-01

    Toll-like receptor 4 (TLR4) plays an important role in innate immunity by eliciting inflammation. Upon receptor engagement, transforming growth factor β-activated kinase 1 (TAK1) is an essential mediator that transmits a signal from the receptor to downstream effectors, IκB kinase (IKK) and the mitogen-activated protein kinases (MAPKs), which control the production of inflammatory cytokines. However, the association between phosphorylation and ubiquitination of TAK1 is not yet clear. Here, we examined the crosstalk between phosphorylation and polyubiquitination of TAK1 and further investigated the mechanism of distinct activation of MAPKs and IKK. Inhibition of TAK1 phosphorylation enhanced Lys63-linked polyubiquitination of TAK1. Conversely, ubiquitin modification was counteracted by phospho-mimic TAK1 mutant, T(184,187)D. Moreover, using LC-MS analysis, Lys562 of TAK1 was identified as a novel Lys63-linked ubiquitination site and as the key residue in the feedback regulation. Mutation of Lys562 of TAK1 leads to a decrease in TAK1 phosphorylation and specific inhibition of the MAPK pathway, but has no effect on formation of the TAK1-containing complex. Our findings demonstrate a feedback loop for phosphorylation and ubiquitination of TAK1, indicating a dynamic regulation between TAK1 polyubiquitiantion and phosphorylated activation, and the molecular mechanism by which IKK and MAPKs are differentially activated in the TLR4 pathway. PMID:26189595

  3. Biological evaluation of synthesized allicin and its transformation products obtained by microwaves in methanol: antioxidant activity and effect on cell growth.

    PubMed

    Ilić, Dušica P; Stojanović, Sanja; Najman, Stevo; Nikolić, Vesna D; Stanojević, Ljiljana P; Tačić, Ana; Nikolić, Ljubiša B

    2015-01-02

    Allicin is the most biologically active substance present in garlic. It can be synthesized or obtained by extraction of fresh garlic. Transformation products of allicin are also biologically active. The aim of this study was to examine the antioxidant activity of synthesized allicin and its transformation products obtained using microwaves in methanol at 55 °C as well as their effect on HeLa cells growth. The antioxidant activity was determined by DPPH (2,2-diphenyl-1-picrylhydrazyl radical) test. The effect on HeLa cells growth was determined by MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) test. For MTT test, allicin and its transformation products were dispersed in carmellose sodium solution and examined in concentrations ranging from 0.3 μg/mL to 3 mg/mL. Allicin showed stronger antioxidant activity than the transformation products. A maximum degree of neutralization of DPPH radicals, about 90%, was reached when the concentration of allicin was 2 mg/mL, with an EC50 (concentration of sample which is required for reduction of the initial concentration DPPH radicals to 50%) value of 0.37 mg/mL. In our study, allicin and its transformation products were not cytotoxic to HeLa cells under the examined conditions. The highest concentration of allicin and its transformation products had a slight antiproliferative effect, with a more pronounced effect of allicin, which reflected on the morphology of HeLa cells. The examined substances are safe to use on epithelial cells at concentrations up to 3 mg/mL when applied in carmellose sodium solution. Using carmellose sodium as a dispersing agent could be recommended as a good approach for testing liposoluble substances in liquid cell cultures.

  4. Receptor dimerization is not a factor in the signalling activity of a transforming variant epidermal growth factor receptor (EGFRvIII).

    PubMed Central

    Chu, C T; Everiss, K D; Wikstrand, C J; Batra, S K; Kung, H J; Bigner, D D

    1997-01-01

    The type-III deletion variant of the epidermal growth factor receptor (EGFRvIII) is frequently found in glioblastomas and other malignant human tumours. Although EGFRvIII confers ligand-independent oncogenic transformation of cell lines, the mechanism by which it promotes aberrant cellular proliferation is unknown. Using cell lines expressing comparable numbers of either wild-type receptor (EGFRwt) or EGFRvIII, we compared several parameters of receptor activation: dimerization, tyrosine phosphorylation and activation of intracellular signalling proteins. Like activated EGFRwt, EGFRvIII was phosphorylated and bound constitutively to the Shc adapter protein. Indeed, EGFRvIII-associated Shc had a higher phosphotyrosine content than Shc associated with stimulated EGFRwt. EGFRwt dimerized in response to either EGF or transforming growth factor alpha. Higher cross-linker concentrations and incubation at higher temperatures (37 degrees C) allowed detection of EGFRwt dimers even in the absence of exogenous ligand. In contrast, EGFRvIII failed to dimerize under any conditions studied. Moreover, neither mitogen-activated protein kinase nor phospholipase Cgamma were phosphorylated in EGFRvIII-expressing cells. We conclude that the deletion of 267 amino acids from the 621-amino-acid N-terminal domain of EGFR does not result simply in a constitutively activated receptor, but alters the spectrum of signalling cascades utilized. Furthermore the ligand-independent transforming activity of EGFRvIII is independent of receptor dimerization. PMID:9210410

  5. Substitution of lysine for arginine at position 42 of human transforming growth factor-alpha eliminates biological activity without changing internal disulfide bonds.

    PubMed Central

    Defeo-Jones, D; Tai, J Y; Vuocolo, G A; Wegrzyn, R J; Schofield, T L; Riemen, M W; Oliff, A

    1989-01-01

    Transforming growth factor-alpha (TGF-alpha) is a growth-promoting protein that binds to the epidermal growth factor (EGF) receptor. To identify critical residues that govern TGF-alpha-EGF receptor binding, we prepared site-specific substitution mutants of TGF-alpha. Mutant proteins were tested in receptor-binding and mitogenesis assays. Semiconservative substitutions at positions 4, 12, 18, and 45 decreased biological activity 2.1- to 14-fold. The conservative substitution of lysine for arginine at position 42 completely eliminated biological activity. Amino acid composition analysis of proteolytic fragments from TGF-alpha and the Lys-42 mutant indicated that these proteins contained the same disulfide bonds. These studies suggest that arginine 42 may be a contact point for TGF-alpha-EGF receptor interaction. PMID:2506441

  6. [Transforming growth factor of beta-type].

    PubMed

    Stoĭka, R S

    1988-01-01

    Recent data about the structure and properties of the beta-type transforming growth factor as well as evidence about its influence on different target cells are presented. The regulatory action of the factor is shown to depend mainly on the type of tested cells, conditions of their culturing and the presence of other bioregulators of cell proliferation in the medium. The prospects of the beta-type transforming growth factor use in practice are considered.

  7. DACH1, a zona glomerulosa selective gene in the human adrenal, activates transforming growth factor-β signaling and suppresses aldosterone secretion.

    PubMed

    Zhou, Junhua; Shaikh, Lalarukh Haris; Neogi, Sudeshna G; McFarlane, Ian; Zhao, Wanfeng; Figg, Nichola; Brighton, Cheryl A; Maniero, Carmela; Teo, Ada E D; Azizan, Elena A B; Brown, Morris J

    2015-05-01

    Common somatic mutations in CACNAID and ATP1A1 may define a subgroup of smaller, zona glomerulosa (ZG)-like aldosterone-producing adenomas. We have therefore sought signature ZG genes, which may provide insight into the frequency and pathogenesis of ZG-like aldosterone-producing adenomas. Twenty-one pairs of zona fasciculata and ZG and 14 paired aldosterone-producing adenomas from 14 patients with Conn's syndrome and 7 patients with pheochromocytoma were assayed by the Affymetrix Human Genome U133 Plus 2.0 Array. Validation by quantitative real-time polymerase chain reaction was performed on genes >10-fold upregulated in ZG (compared with zona fasciculata) and >10-fold upregulated in aldosterone-producing adenomas (compared with ZG). DACH1, a gene associated with tumor progression, was further analyzed. The role of DACH1 on steroidogenesis, transforming growth factor-β, and Wnt signaling activity was assessed in the human adrenocortical cell line, H295R. Immunohistochemistry confirmed selective expression of DACH1 in human ZG. Silencing of DACH1 in H295R cells increased CYP11B2 mRNA levels and aldosterone production, whereas overexpression of DACH1 decreased aldosterone production. Overexpression of DACH1 in H295R cells activated the transforming growth factor-β and canonical Wnt signaling pathways but inhibited the noncanonical Wnt signaling pathway. Stimulation of primary human adrenal cells with angiotensin II decreased DACH1 mRNA expression. Interestingly, there was little overlap between our top ZG genes and those in rodent ZG. In conclusion, (1) the transcriptome profile of human ZG differs from rodent ZG, (2) DACH1 inhibits aldosterone secretion in human adrenals, and (3) transforming growth factor-β signaling pathway is activated in DACH1 overexpressed cells and may mediate inhibition of aldosterone secretion in human adrenals.

  8. TRPC1-STIM1 activation modulates transforming growth factor β-induced epithelial-to-mesenchymal transition

    PubMed Central

    Schaar, Anne; Sukumaran, Pramod; Sun, Yuyang; Dhasarathy, Archana; Singh, Brij B

    2016-01-01

    Activation of Epithelial-to-Mesenchymal Transition (EMT) is important for tumor metastasis. Although growth factors such as TGFβ and EGF have been shown to induce EMT in breast epithelial cells, the mechanism resulting in migration is not well understood. Herein, we provide evidence that Ca2+ entry into the cell, especially upon store-depletion, plays an important role in TGFβ-induced EMT by promoting cellular migration and potentially leading to metastasis. The increased migration by TGFβ in non-cancerous cells was due to the loss of E-cadherin along with a subsequent increase in N-cadherin levels. Importantly, TGFβ-treatment increases store-mediated Ca2+ entry, which was essential for the activation of calpain leading to the loss of E-cadherin and MMP activation. Inhibition of Ca2+ entry by using Ca2+ channel blocker SKF-96365, significantly decreased Ca2+ entry, decreased TGFβ-induced calpain activation, and suppressed the loss of E-cadherin along with inhibiting cell migration. Furthermore, TRPC1 function as an endogenous Ca2+ entry channel and silencing of either TRPC1 or its activator, STIM1, significantly decreased TGFβ induced Ca2+ entry, inhibited TGFβ-mediated calpain activation and cell migration. In contrast, overexpression of TRPC1 showed increased Ca2+ entry and promoted TGFβ-mediated cell migration. Moreover, increased TRPC1 expression was observed in ductal carcinoma cells. Together these results suggest that disrupting Ca2+ influx via TRPC1/STIM1 mechanism reduces calpain activity, which could restore intercellular junction proteins thereby inhibiting EMT induced motility. PMID:27793015

  9. Disruption of thioredoxin metabolism enhances the toxicity of transforming growth factor β-activated kinase 1 (TAK1) inhibition in KRAS-mutated colon cancer cells

    PubMed Central

    Hrabe, Jennifer E.; O’Leary, Brianne R.; Fath, Melissa A.; Rodman, Samuel N.; Button, Anna M.; Domann, Frederick E.; Spitz, Douglas R.; Mezhir, James J.

    2015-01-01

    Transforming growth factor β-activated kinase 1 (TAK1) is critical for survival of many KRAS mutated colorectal cancer cells, and TAK1 inhibition with 5Z-7-oxozeaenol has been associated with oxidative stress leading to tumor cell killing. When SW 620 and HCT 116 human colon cancer cells were treated with 5 µM 5Z-7-oxozeaenol, cell viability, growth, and clonogenic survival were significantly decreased. Consistent with TAK1 inhibition being causally related to thiol-mediated oxidative stress, 10 mM N-acetylcysteine (NAC) partially reversed the growth inhibitory effects of 5Z-7-oxozeaenol. In addition, 5Z-7-oxozeaenol also increased steady-state levels of H2DCFDA oxidation as well as increased levels of total glutathione (GSH) and glutathione disulfide (GSSG). Interestingly, depletion of GSH using buthionine sulfoximine did not significantly potentiate 5Z-7-oxozeaenol toxicity in either cell line. In contrast, pre-treatment of cells with auranofin (Au) to inhibit thioredoxin reductase activity significantly increased levels of oxidized thioredoxin as well as sensitized cells to 5Z-7-oxozeaenol-induced growth inhibition and clonogenic cell killing. These results were confirmed in SW 620 murine xenografts, where treatment with 5Z-7-oxozeaenol or with Au plus 5Z-7-oxozeaenol significantly inhibited growth, with Au plus 5Z-7-oxozeaenol trending toward greater growth inhibition compared to 5Z-7-oxozeaenol alone. These results support the hypothesis that thiol-mediated oxidative stress is causally related to TAK1-induced colon cancer cell killing. In addition, these results support the hypothesis that thioredoxin metabolism is a critical target for enhancing colon cancer cell killing via TAK1 inhibition and could represent an effective therapeutic strategy in patients with these highly resistant tumors. PMID:26114584

  10. Transforming growth factor β signaling upregulates the expression of human GDP-fucose transporter by activating transcription factor Sp1.

    PubMed

    Xu, Yu-Xin; Ma, Anna; Liu, Li

    2013-01-01

    GDP-fucose transporter plays a crucial role in fucosylation of glycoproteins by providing activated fucose donor, GDP-fucose, for fucosyltransferases in the lumen of the Golgi apparatus. Fucose-containing glycans are involved in many biological processes, which are essential for growth and development. Mutations in the GDP-fucose transporter gene cause leukocyte adhesion deficiency syndrome II, a disease characterized by slow growth, mental retardation and immunodeficiency. However, no information is available regarding its transcriptional regulation. Here, by using human cells, we show that TGF-β1 specifically induces the GDP-fucose transporter expression, but not other transporters tested such as CMP-sialic acid transporter, suggesting a diversity of regulatory pathways for the expression of these transporters. The regulatory elements that are responsive to the TGF-β1 stimulation are present in the region between bp -330 and -268 in the GDP-fucose transporter promoter. We found that this region contains two identical octamer GC-rich motifs (GGGGCGTG) that were demonstrated to be essential for the transporter expression. We also show that the transcription factor Sp1 specifically binds to the GC-rich motifs in vitro and Sp1 coupled with phospho-Smad2 is associated with the promoter region covering the Sp1-binding motifs in vivo using chromatin immunoprecipitation (ChIP) assays. In addition, we further confirmed that Sp1 is essential for the GDP-fucose transporter expression stimulated by TGF-β1 using a luciferase reporter system. These results highlight the role of TGF-β signaling in regulation of the GDP-fucose transporter expression via activating Sp1. This is the first transcriptional study for any nucleotide sugar transporters that have been identified so far. Notably, TGF-β1 receptor itself is known to be modified by fucosylation. Given the essential role of GDP-fucose transporter in fucosylation, the finding that TGF-β1 stimulates the expression of

  11. Transforming growth factor beta and cyclosporin A inhibit the inducible activity of the interleukin-2 gene in T cells through a noncanonical octamer-binding site.

    PubMed Central

    Brabletz, T; Pfeuffer, I; Schorr, E; Siebelt, F; Wirth, T; Serfling, E

    1993-01-01

    Transforming growth factor beta (TGF-beta) has a growth-inhibitory effect on numerous different cell types of the immune system, including T lymphocytes. We show in this study that the inhibitory action of TGF-beta on T lymphocytes is accompanied by a block of interleukin 2 (IL-2) gene expression which is mediated, at least in part, by inhibition of IL-2 promoter/enhancer activity. The functional analysis of cis-regulatory (proto-enhancer) elements of the IL-2 enhancer/promoter region showed that the most TGF-beta-responsive element maps to its so-called upstream promoter site. The proto-enhancer activity of the upstream promoter site element is also inhibited by cyclosporin A. The upstream promoter site DNA harbors two noncanonical, closely linked binding sequences for octamer and AP-1-like factors. Both sites are involved in the establishment of IL-2 enhancer activity. Since the activity of genuine octamer sites but not that of AP-1-binding sites is also impaired by TGF-beta and cyclosporin A in El4 T lymphoma cells, we conclude that both immunosuppressives interfere with the activity but not the DNA binding of octamer factors in T lymphocytes. Images PMID:8423782

  12. Inhibition of Transforming Growth Factor-Beta1 SignalingAttenuates Ataxia Telangiectasia Mutated Activity in Response toGenotoxic Stress

    SciTech Connect

    Kirshner, Julia; Jobling, Michael F.; Pajares, Maria Jose; Ravani, Shraddha A.; Glick, Adam; Lavin, Martin F.; Koslov, Sergei; Shiloh, Yosef; Barcellos-Hoff, Mary Helen

    2006-01-01

    Ionizing radiation causes DNA damage that elicits a cellular program of damage control coordinated by the kinase activity of ataxia telangiectasia mutated protein (ATM). Transforming growth factor {beta} (TGF{beta})-1, which is activated by radiation, is a potent and pleiotropic mediator of physiologic and pathologic processes. Here we show that TGF{beta} inhibition impedes the canonical cellular DNA damage stress response. Irradiated Tgf{beta}I null murine epithelial cells or human epithelial cells treated with a small-molecule inhibitor of TGF{beta} type I receptor kinase exhibit decreased phosphorylation of Chk2, Rad17, and p53; reduced H2AX radiation-induced foci; and increased radiosensitivity compared with TGF{beta} competent cells. We determined that loss of TGF{beta} signaling in epithelial cells truncated ATM autophosphorylation and significantly reduced its kinase activity, without affecting protein abundance. Addition of TGF{beta} restored functional ATM and downstream DNA damage responses. These data reveal a heretofore undetected critical link between the microenvironment and ATM, which directs epithelial cell stress responses, cell fate, and tissue integrity. Thus, Tgf{beta}I, in addition to its role in homoeostatic growth control, plays a complex role in regulating responses to genotoxic stress, the failure of which would contribute to the development of cancer; conversely, inhibiting TGF{beta} may be used to advantage in cancer therapy.

  13. Translation of CUG- but not AUG-initiated forms of human fibroblast growth factor 2 is activated in transformed and stressed cells

    PubMed Central

    1996-01-01

    Four isoforms of the human fibroblast growth factor 2 (FGF-2), with different intracellular localizations and distinct effects on cell phenotype, result from alternative initiations of translation at three CUG and one AUG start codons. We showed here by Western immunoblotting and immunoprecipitation that the CUG-initiated forms of FGF-2 were synthesized in transformed cells, whereas "normal" cells almost exclusively produced the AUG-initiated form. CUG-initiated FGF-2 was induced in primary skin fibroblasts in response to heat shock and oxidative stress. In transformed cells and in stressed fibroblasts, CUG expression was dependent on cis-elements within the 5' region of FGF-2 mRNA and was not correlated to mRNA level, indicating a translational regulation. UV cross-linking experiments revealed that CUG expression was linked to the binding of several cellular proteins to FGF-2 mRNA 5' region. Since translation of FGF-2 mRNA was previously shown to occur by internal ribosome entry, a nonclassical mechanism already described for picornaviruses, the cross-linking patterns of FGF-2 and picornavirus mRNAs were compared. Comigration of several proteins, including a p60, was observed. However, this p60 was shown to be different from the p57/PTB internal entry factor, suggesting a specificity towards FGF-2 mRNA. We report here a process of translational activation of the FGF-2 CUG-initiated forms in direct relation with trans-acting factors specific to transformed and stressed cells. These data favor a critical role of CUG-initiated FGF-2 in cell transformation and in the stress response. PMID:8947560

  14. Thrombospondin-1 (TSP-1) analogs ABT-510 and ABT-898 inhibit prolactinoma growth and recover active pituitary transforming growth factor-β1 (TGF-β1).

    PubMed

    Recouvreux, M Victoria; Camilletti, M Andrea; Rifkin, Daniel B; Becu-Villalobos, Damasia; Díaz-Torga, Graciela

    2012-08-01

    Prolactinomas are the most prevalent type of secreting pituitary tumors in humans and generally respond well to a medical therapy with dopamine agonists. However, for patients exhibiting resistance to dopaminergic drugs, alternative treatments are desired. Antiangiogenic strategies might represent a potential therapy for these tumors. Thrombospondin 1 (TSP-1) is a large multifunctional glycoprotein involved in multiple biological processes including angiogenesis, apoptosis, and activation of TGF-β1. Because tumors that overexpress TSP-1 grow more slowly, have fewer metastases, and have decreased angiogenesis, TSP-1 provides a novel target for cancer treatment. ABT-510 and ABT-898 are TSP-1 synthetic analogs that mimic its antiangiogenic action. In the present study, we explored the potential effect of ABT-510 and ABT-898 on experimental prolactinomas induced by chronic diethylstilbestrol (DES) treatment in female rats. We demonstrated that a 2-wk treatment with ABT-510 and ABT-898 counteracted the increase in pituitary size and serum prolactin levels as well as the pituitary proliferation rate induced by DES. These inhibitory effects on tumor growth could be mediated by the antiangiogenic properties of the drugs. We also demonstrated that ABT-510 and ABT-898, in addition to their described antiangiogenic effects, increased active TGF-β1 level in the tumors. We postulate that the recovery of the local cytokine activation participates in the inhibition of lactotrope function. These results place these synthetic TSP-1 analogs as potential alternative or complementary treatments in dopamine agonist-resistant prolactinomas.

  15. Tripartite Motif 8 Contributes to Pathological Cardiac Hypertrophy Through Enhancing Transforming Growth Factor β-Activated Kinase 1-Dependent Signaling Pathways.

    PubMed

    Chen, Lijuan; Huang, Jia; Ji, Yan-Xiao; Mei, Fanghua; Wang, Pi-Xiao; Deng, Ke-Qiong; Jiang, Xi; Ma, Genshan; Li, Hongliang

    2017-02-01

    Tripartite motif (TRIM) 8 functions as an E3 ubiquitin ligase, interacting with and ubiquitinating diverse substrates, and is implicated in various pathological processes. However, the function of TRIM8 in the heart remains largely uncharacterized. This study aims to explore the role of TRIM8 in the development of pathological cardiac hypertrophy. Mice and isolated neonatal rat cardiomyocytes overexpressing or lacking TRIM8 were examined in several experiments. The effect of aortic banding-induced cardiac hypertrophy was analyzed by echocardiographic, pathological and molecular analyses. Our results indicated that the TRIM8 overexpression in hearts exacerbated the cardiac hypertrophy triggered by aortic banding. In contrast, the development of pathological cardiac hypertrophy was profoundly blocked in TRIM8-deficient hearts. Mechanistically, our study suggests that TRIM8 may elicit cardiodetrimental effects by promoting the activation of transforming growth factor β-activated kinase 1 (TAK1)-p38/JNK signaling pathways. Similar results were observed in cultured neonatal rat cardiomyocytes treated with angiotensin II. The rescue experiments using the TAK1-specific inhibitor 5z-7-ox confirmed the requirement of TAK1 activation in TRIM8-mediated pathological cardiac hypertrophy. Furthermore, TRIM8 contributed to TAK1 activation by binding to and promoting TAK1 ubiquitination. In conclusion, our study demonstrates that TRIM8 plays a deleterious role in pressure overload-induced cardiac hypertrophy by accelerating the activation of TAK1-dependent signaling pathways.

  16. In vivo transformation of factor-dependent hemopoietic cells: role of intracisternal A-particle transposition for growth factor gene activation.

    PubMed Central

    Dührsen, U; Stahl, J; Gough, N M

    1990-01-01

    Cells of the granulocyte-macrophage colony stimulating factor (GM-CSF) or multi-lineage colony stimulating factor (Multi-CSF) dependent line FDC-P1 undergo leukemic transformation after injection into irradiated DBA/2 mice. About one third of factor-independent FDC-P1 variants isolated from leukemic animals express GM-CSF or Multi-CSF, assessed either by bioassay or by sensitive RNA detection using the polymerase chain reaction. All of the GM-CSF-secreting lines studied had a rearrangement in one allele of the GM-CSF gene, three of four Multi-CSF-secreting lines had Multi-CSF gene rearrangements, while factor-independent lines lacking evidence of growth factor production had no demonstrable CSF gene alterations. All rearrangements were characterized by insertions of novel DNA in the 5'-flanking regions of the CSF genes. The inserted segments of DNA varied in size between 0.35 and 6.5 kb and displayed restriction enzyme cleavage maps reminiscent of intracisternal A-particle (IAP) genomes. This was confirmed in two cases by molecular cloning and nucleotide sequence analysis. In these instances, the insertion consisted of solitary IAP long terminal repeats. The transformation system described provides a model for the study of IAP transpositions and their effects on gene activation. Images Fig. 2. Fig. 3. Fig. 4. Fig. 6. Fig. 9. PMID:2108861

  17. Transforming Growth Factor β Suppresses Peroxisome Proliferator-Activated Receptor γ Expression via Both SMAD Binding and Novel TGF-β Inhibitory Elements.

    PubMed

    Lakshmi, Sowmya P; Reddy, Aravind T; Reddy, Raju C

    2017-01-18

    Transforming growth factor β (TGF-β) contributes to wound healing and, when dysregulated, to pathological fibrosis. TGF-β and the anti-fibrotic nuclear hormone receptor peroxisome proliferator-activated receptor γ (PPARγ) repress each other's expression, and such PPARγ downregulation is prominent in fibrosis and mediated, via previously unknown mechanisms, by SMAD signaling. Here we show that TGF-β induces association of SMAD3 with both SMAD4, needed for translocation of the complex into the nucleus, and the essential context-sensitive corepressors E2F4 and p107. The complex mediates TGF-β-induced repression by binding to regulatory elements in the target promoter. In the PPARG promoter, we found that the SMAD3-SMAD4 complex binds both to a previously unknown consensus TGF-β inhibitory element (TIE) and also to canonical SMAD-binding elements (SBEs). Furthermore, the TIE and SBEs independently mediated partial repression of PPARG transcription, the first demonstration of a TIE and SBEs functioning within the same promoter. Also, TGF-β-treated fibroblasts contained SMAD complexes that activated a SMAD target gene in addition to those repressing PPARG transcription, the first finding of such dual activity within the same cell. These findings describe in detail novel mechanisms by which TGF-β represses PPARG transcription, thereby facilitating its own pro-fibrotic activity.

  18. Epidermal growth factor receptor transactivation is implicated in IL-6-induced proliferation and ERK1/2 activation in non-transformed prostate epithelial cells.

    PubMed

    Poncet, Nadège; Guillaume, Johann; Mouchiroud, Guy

    2011-03-01

    Epidermal growth factor receptor (EGF-R) is a receptor tyrosine kinase that can be activated by molecules other than its cognate ligands. This form of crosstalk called transactivation is frequently observed in both physiological and pathological cellular responses, yet it involves various mechanisms. Using the RWPE-1 cell line as a model of non-transformed prostate epithelial progenitor cells, we observed that interleukin-6 (IL-6) is able to promote cell proliferation and ERK1/2 activation provided that EGF-R kinase activity is not impaired. Treatment with GM6001, a general matrix metalloprotease inhibitor, indicated that IL-6 activates EGF-R through cleavage and release of membrane-anchored EGF-R ligands. Several inhibitors were used to test implication of "a disintegrin and metalloprotease" ADAM10 and ADAM17. GW280264X that targets both ADAM10 and ADAM17 blocked IL-6-induced proliferation and ERK1/2 phosphorylation with same potency as GM6001. However, ADAM10 inhibitor GI254023X and ADAM17 inhibitor TAPI-2 were less efficient in inhibiting response of RWPE-1 cells to IL-6, indicating possible cooperation of ADAM17 with ADAM10 or other metalloproteases. Accordingly, our findings suggest that IL-6 stimulates shedding of EGF-R ligands and transactivation of EGF-R in normal prostate epithelial cells, which may be an important mechanism to promote cell proliferation in inflammatory prostate.

  19. Transforming Growth Factor-β-Activated Kinase 1 Is Required for Human FcγRIIIb-Induced Neutrophil Extracellular Trap Formation.

    PubMed

    Alemán, Omar Rafael; Mora, Nancy; Cortes-Vieyra, Ricarda; Uribe-Querol, Eileen; Rosales, Carlos

    2016-01-01

    Neutrophils (PMNs) are the most abundant leukocytes in the blood. PMN migrates from the circulation to sites of infection where they are responsible for antimicrobial functions. PMN uses phagocytosis, degranulation, and formation of neutrophil extracellular traps (NETs) to kill microbes. Several stimuli, including bacteria, fungi, and parasites, and some pharmacological compounds, such as Phorbol 12-myristate 13-acetate (PMA), are efficient inducers of NETs. Antigen-antibody complexes are also capable of inducing NET formation. Recently, it was reported that FcγRIIIb cross-linking induced NET formation similarly to PMA stimulation. Direct cross-linking of FcγRIIA or integrins did not promote NET formation. FcγRIIIb-induced NET formation presented different kinetics from PMA-induced NET formation, suggesting differences in signaling. Because FcγRIIIb also induces a strong activation of extracellular signal-regulated kinase (ERK) and nuclear factor Elk-1, and the transforming growth factor-β-activated kinase 1 (TAK1) has recently been implicated in ERK signaling, in the present report, we explored the role of TAK1 in the signaling pathway activated by FcγRIIIb leading to NET formation. FcγRIIIb was stimulated by specific monoclonal antibodies, and NET formation was evaluated in the presence or absence of pharmacological inhibitors. The antibiotic LL Z1640-2, a selective inhibitor of TAK1 prevented FcγRIIIb-induced, but not PMA-induced NET formation. Both PMA and FcγRIIIb cross-linking induced phosphorylation of ERK. But, LL Z1640-2 only inhibited the FcγRIIIb-mediated activation of ERK. Also, only FcγRIIIb, similarly to transforming growth factor-β-induced TAK1 phosphorylation. A MEK (ERK kinase)-specific inhibitor was able to prevent ERK phosphorylation induced by both PMA and FcγRIIIb. These data show for the first time that FcγRIIIb cross-linking activates TAK1, and that this kinase is required for triggering the MEK/ERK signaling pathway to NETosis.

  20. Transforming Growth Factor-β-Activated Kinase 1 Is Required for Human FcγRIIIb-Induced Neutrophil Extracellular Trap Formation

    PubMed Central

    Alemán, Omar Rafael; Mora, Nancy; Cortes-Vieyra, Ricarda; Uribe-Querol, Eileen; Rosales, Carlos

    2016-01-01

    Neutrophils (PMNs) are the most abundant leukocytes in the blood. PMN migrates from the circulation to sites of infection where they are responsible for antimicrobial functions. PMN uses phagocytosis, degranulation, and formation of neutrophil extracellular traps (NETs) to kill microbes. Several stimuli, including bacteria, fungi, and parasites, and some pharmacological compounds, such as Phorbol 12-myristate 13-acetate (PMA), are efficient inducers of NETs. Antigen–antibody complexes are also capable of inducing NET formation. Recently, it was reported that FcγRIIIb cross-linking induced NET formation similarly to PMA stimulation. Direct cross-linking of FcγRIIA or integrins did not promote NET formation. FcγRIIIb-induced NET formation presented different kinetics from PMA-induced NET formation, suggesting differences in signaling. Because FcγRIIIb also induces a strong activation of extracellular signal-regulated kinase (ERK) and nuclear factor Elk-1, and the transforming growth factor-β-activated kinase 1 (TAK1) has recently been implicated in ERK signaling, in the present report, we explored the role of TAK1 in the signaling pathway activated by FcγRIIIb leading to NET formation. FcγRIIIb was stimulated by specific monoclonal antibodies, and NET formation was evaluated in the presence or absence of pharmacological inhibitors. The antibiotic LL Z1640-2, a selective inhibitor of TAK1 prevented FcγRIIIb-induced, but not PMA-induced NET formation. Both PMA and FcγRIIIb cross-linking induced phosphorylation of ERK. But, LL Z1640-2 only inhibited the FcγRIIIb-mediated activation of ERK. Also, only FcγRIIIb, similarly to transforming growth factor-β-induced TAK1 phosphorylation. A MEK (ERK kinase)-specific inhibitor was able to prevent ERK phosphorylation induced by both PMA and FcγRIIIb. These data show for the first time that FcγRIIIb cross-linking activates TAK1, and that this kinase is required for triggering the MEK/ERK signaling pathway to

  1. Transforming growth factor beta-activated kinase 1 (TAK1)-dependent checkpoint in the survival of dendritic cells promotes immune homeostasis and function.

    PubMed

    Wang, Yanyan; Huang, Gonghua; Vogel, Peter; Neale, Geoffrey; Reizis, Boris; Chi, Hongbo

    2012-02-07

    Homeostatic control of dendritic cell (DC) survival is crucial for adaptive immunity, but the molecular mechanism is not well defined. Moreover, how DCs influence immune homeostasis under steady state remains unclear. Combining DC-specific and -inducible deletion systems, we report that transforming growth factor beta-activated kinase 1 (TAK1) is an essential regulator of DC survival and immune system homeostasis and function. Deficiency of TAK1 in CD11c(+) cells induced markedly elevated apoptosis, leading to the depletion of DC populations, especially the CD8(+) and CD103(+) DC subsets in lymphoid and nonlymphoid tissues, respectively. TAK1 also contributed to DC development by promoting the generation of DC precursors. Prosurvival signals from Toll-like receptors, CD40 and receptor activator of nuclear factor-κB (RANK) are integrated by TAK1 in DCs, which in turn mediated activation of downstream NF-κB and AKT-Foxo pathways and established a gene-expression program. TAK1 deficiency in DCs caused a myeloid proliferative disorder characterized by expansion of neutrophils and inflammatory monocytes, disrupted T-cell homeostasis, and prevented effective T-cell priming and generation of regulatory T cells. Moreover, TAK1 signaling in DCs was required to prevent myeloid proliferation even in the absence of lymphocytes, indicating a previously unappreciated regulatory mechanism of DC-mediated control of myeloid cell-dependent inflammation. Therefore, TAK1 orchestrates a prosurvival checkpoint in DCs that affects the homeostasis and function of the immune system.

  2. Nod-like receptor protein 3 inflammasome activation by Escherichia coli RNA induces transforming growth factor beta 1 secretion in hepatic stellate cells

    PubMed Central

    Wang, Hui; Liu, Shu; Wang, Ying; Chang, Bing; Wang, Bingyuan

    2016-01-01

    Nod-like receptor protein 3 (NLRP3) inflammasome has been implicated in alcoholic liver disease. Chronic alcohol consumption enhances gut permeability and causes microbial translocation. The present study explored the activation of the NLRP3 inflammasome by Escherichia coli RNA in hepatic stellate cells (HSCs), and the potential role of NLRP3 inflammasome in hepatic fibrosis. E. coli RNA transfection induced HSC-T6 cells to secrete and express mature interleukin-1 beta (IL-1β), which was abolished by NLRP3 siRNA pretreatment. In addition, E. coli RNA transfection enhanced caspase-1 expression, whereas reduced caspase-1 precursor (pro-caspase-1) expression. E. coli RNA-stimulated transforming growth factor beta 1 (TGF-β1) overproduction in HSC-T6 cells, which was blocked by recombinant IL-1 receptor antagonist (rIL-1Ra) or nuclear factor κB inhibitor BAY 11-7082. Furthermore, E. coli RNA-induced overexpression of pro-fibrogenic factors was suppressed by rIL-1Ra or TGF-β receptor inhibitor A83-01. These results demonstrate that E. coli RNA can stimulate NLRP3 inflammasome activation, which leads to excessive production of pro-fibrogenic factors, suggesting that NLRP3 inflammasome activation in HSCs may play a role in hepatic fibrosis. PMID:26773180

  3. Aberrant mucosal mast cell protease expression in the enteric epithelium of nematode-infected mice lacking the integrin alphavbeta6, a transforming growth factor-beta1 activator.

    PubMed

    Knight, Pamela A; Brown, Jeremy K; Wright, Steven H; Thornton, Elisabeth M; Pate, Judith A; Miller, Hugh R P

    2007-10-01

    Infection of mice with the nematode Trichinella spiralis triggers recruitment and differentiation of intraepithelial intestinal mucosal mast cells expressing mouse mast cell protease 1 (Mcpt-1), which contributes to expulsion of the parasite. Expression of Mcpt-1 is transforming growth factor (TGF)-beta1-dependent in vitro. TGF-beta1, which is secreted within tissues as a biologically inactive complex with latency-associated peptide, requires extracellular modification to become functionally active. The integrin-alpha(nu)beta(6) mediates local activation of TGF-beta(1) in association with epithelia. Using T. spiralis-infected beta(6)(-/-) mice, we show accumulation of mucosal mast cells in the lamina propria of the small intestine with minimal recruitment into the epithelial compartment. This was accompanied by a coordinate reduction in expression of both Mcpt-1 and -2 in the jejunum and increased tryptase expression, whereas Mcpt-9 became completely undetectable. In contrast, the cytokine stem cell factor, a regulator of mast cell differentiation and survival, was significantly up-regulated in T. spiralis-infected beta(6)(-/-) mice compared with infected beta(6)(+/+) controls. Despite these changes, beta(6)(-/-) mice still appeared to expel the worms normally. We postulate that compromised TGF-beta(1) activation within the gastrointestinal epithelial compartment is a major, but not the only, contributing factor to the observed changes in mucosal mast cell protease and epithelial cytokine expression in beta(6)(-/-) mice.

  4. Transforming growth factor β-activated kinase 1 negatively regulates interleukin-1α-induced stromal-derived factor-1 expression in vascular smooth muscle cells

    SciTech Connect

    Yang, Bin; Li, Wei; Zheng, Qichang; Qin, Tao; Wang, Kun; Li, Jinjin; Guo, Bing; Yu, Qihong; Wu, Yuzhe; Gao, Yang; Cheng, Xiang; Hu, Shaobo; Kumar, Stanley Naveen; Liu, Sanguang; Song, Zifang

    2015-07-17

    Stromal-derived Factor-1 (SDF-1) derived from vascular smooth muscle cells (VSMCs) contributes to vascular repair and remodeling in various vascular diseases. In this study, the mechanism underlying regulation of SDF-1 expression by interleukin-1α (IL-1α) was investigated in primary rat VSMCs. We found IL-1α promotes SDF-1 expression by up-regulating CCAAT-enhancer-binding protein β (C/EBPβ) in an IκB kinase β (IKKβ) signaling-dependent manner. Moreover, IL-1α-induced expression of C/EBPβ and SDF-1 was significantly potentiated by knockdown of transforming growth factor β-activated kinase 1 (TAK1), an upstream activator of IKKβ signaling. In addition, we also demonstrated that TAK1/p38 mitogen-activated protein kinase (p38 MAPK) signaling exerted negative effect on IL-1α-induced expression of C/EBPβ and SDF-1 through counteracting ROS-dependent up-regulation of nuclear factor erythroid 2-related factor 2 (NRF2). In conclusion, TAK1 acts as an important regulator of IL-1α-induced SDF-1 expression in VSMCs, and modulating activity of TAK1 may serve as a potential strategy for modulating vascular repair and remodeling. - Highlights: • IL-1α induces IKKβ signaling-dependent SDF-1 expression by up-regulating C/EBPβ. • Activation of TAK1 by IL-1α negatively regulates C/EBPβ-dependent SDF-1 expression. • IL-1α-induced TAK1/p38 MAPK signaling counteracts ROS-dependent SDF-1 expression. • TAK1 counteracts IL-1α-induced SDF-1 expression by attenuating NRF2 up-regulation.

  5. Effects of Acute Confinement Stress-induced Hypothalamic-Pituitary Adrenal Axis Activation and Concomitant Peripheral and Central Transforming Growth Factor-β1 Measures in Nonhuman Primates

    PubMed Central

    Coplan, Jeremy D.; Gopinath, Srinath; Abdallah, Chadi G.; Margolis, Jeffrey; Chen, Wei; Scharf, Bruce A.; Rosenblum, Leonard A.; Batuman, Olcay A.; Smith, Eric L. P.

    2017-01-01

    Transforming growth factor-β1 (TGF-β1) is a multifunctional cytokine with anti-inflammatory, immunosuppressive and neuroprotective properties. The hypothalamic-pituitary-adrenal (HPA) axis and immune system exert bidirectional influences on each other, via cortisol and TGF-β1, but the exact nature of the interaction is not well characterized. The current study examined the effects, in bonnet macaques (Macaca radiata), of two consecutive acute confinement stress periods in an unfamiliar room while mildly restrained, first without and then with dexamethasone pretreatment (0.01 mg/kg IM). Preceding the confinement studies, a non-stress control condition obtained contemporaneous levels of cortisol and TGF-β1 in both plasma and cerebrospinal fluid (CSF) to match the confinement stress studies. Subjects were reared under either normative or variable foraging demand (VFD) conditions. Since there were no rearing effects at baseline or for any of the conditions tested -- either for cortisol or TGF-β -- the study analyses were conducted on the combined rearing groups. The stress condition increased both plasma and CSF cortisol levels whereas dexamethasone pretreatment decreased cortisol concentrations to below baseline levels despite stress. The stress condition decreased TGF-β1 concentrations only in CSF but not in serum. Together the data suggested that stress-induced reductions of a centrally active neuroprotective cytokine occurs in the face of HPA axis activation, potentially facilitating glucocortoid-induced neurotoxicity. Stress-induced reductions of neuroprotective cytokines prompts exploration of protective measures against glucocorticoid-induced neurotoxicity.

  6. Transforming growth factor-β and Smads.

    PubMed

    Lan, Hui Yao; Chung, Arthur C K

    2011-01-01

    Diabetic nephropathy (DN) is a major diabetic complication. Transforming growth factor-β(TGF-β) is a key mediator in the development of diabetic complications. It is well known that TGF-β exerts its biological effects by activating downstream mediators, called Smad2and Smad3, which is negatively regulated by an inhibitory Smad7. Recent studies also demonstrated that under disease conditions Smads act as signal integrators and interact with other signaling pathways such as the MAPK and NF-κB pathways. In addition, Smad2and Smad3 can reciprocally regulate target genes of TGF-β signaling. Novel research into microRNA has revealed the complexity of TGF-β signaling during DN. It has been found that TGF-β and elevated glucose concentration can positively regulate miR-192 and miR-377, but negatively regulate miR-29a in a diabetic milieu. These microRNAs are found to contribute to DN. Although targeting TGF-β may exert adverse effects on immune system, therapeutic approach against TGF-β signaling during DN still draws much attention. Blocking TGF-β signaling by neutralizing antibody, anti-sense oligonucleotides, and soluble receptors have been tested, but effects are limited. Gene transfer of Smad7 into diseased kidneys demonstrates a prominent inhibition on renal fibrosis and amelioration of renal impairment. Alteration of TGF-β-regulated microRNA expression in diseased kidneys may provide an alternative therapeutic approach against DN. In conclusion, TGF-β/Smad signaling plays a critical role in DN. A better understanding of the role of TGF-β/Smad signaling in the development of DN should provide an effective therapeutic strategy to combat DN.

  7. Inhibition of transforming growth factor β-activated kinase 1 prevents inflammation-related cartilage degradation in osteoarthritis

    PubMed Central

    Cheng, Jin; Hu, Xiaoqing; Dai, Linghui; Zhang, Xin; Ren, Bo; Shi, Weili; Liu, Zhenlong; Duan, Xiaoning; Zhang, Jiying; Fu, Xin; Chen, Wenqing; Ao, Yingfang

    2016-01-01

    Osteoarthritis (OA) is a common debilitating joint disorder, there’s still no available disease-modifying drug for OA currently. This study aims to explore the role of TAK1 in OA pathogenesis and therapeutic efficiency of TAK1 inhibition for OA. The contribution of TAK1 to OA pathogenesis was investigated by intra-articular injection of TAK1-encoding adenovirus in rats. TAK1 inhibitor 5Z-7-induced expression changes of extracellular matrix (ECM)-related genes were detected by real-time PCR. The protective effect of 5Z-7 against OA progression was evaluated in a post-traumatic OA rat model. Our results showed that intra-articular injection of Ad-Tak1 induced cartilage destruction and OA-related cytokine secretion in rat joints. TAK1 inhibition by 5Z-7 efficiently blocked NF-κB, JNK and p38 pathways activation in OA chondrocytes and synoviocytes, Meanwhile, 5Z-7 significantly decreased the expression of matrix-degrading enzymes and pro-inflammatory cytokine, while increased ECM protein expression, which are all crucial components in OA. 5Z-7 also ameliorated ECM loss in OA cartilage explants. More importantly, 5Z-7 significantly protected against cartilage destruction in a rat model of OA. In conclusion, our findings provide the first in vivo evidence that TAK1 contributes to OA by disrupting cartilage homeostasis, thus represents an ideal target for OA treatment, with 5Z-7 as a candidate therapeutic. PMID:27682596

  8. Transforming Growth Factor β1 (TGF-β1) Activates Hepcidin mRNA Expression in Hepatocytes.

    PubMed

    Chen, Simeng; Feng, Teng; Vujić Spasić, Maja; Altamura, Sandro; Breitkopf-Heinlein, Katja; Altenöder, Jutta; Weiss, Thomas S; Dooley, Steven; Muckenthaler, Martina U

    2016-06-17

    The hepatic hormone hepcidin is the master regulator of systemic iron homeostasis. Its expression level is adjusted to alterations in iron levels, inflammatory cues, and iron requirements for erythropoiesis. Bone morphogenetic protein 6 (BMP6) contributes to the iron-dependent control of hepcidin. In addition, TGF-β1 may stimulate hepcidin mRNA expression in murine hepatocytes and human leukocytes. However, receptors and downstream signaling proteins involved in TGF-β1-induced hepcidin expression are still unclear. Here we show that TGF-β1 treatment of mouse and human hepatocytes, as well as ectopic expression of TGF-β1 in mice, increases hepcidin mRNA levels. The hepcidin response to TGF-β1 depends on functional TGF-β1 type I receptor (ALK5) and TGF-β1 type II receptor (TβRII) and is mediated by a noncanonical mechanism that involves Smad1/5/8 phosphorylation. Interestingly, increasing availability of canonical Smad2/3 decreases TGF-β1-induced hepcidin regulation, whereas the BMP6-hepcidin signal was enhanced, indicating a signaling component stoichiometry-dependent cross-talk between the two pathways. Although ALK2/3-dependent hepcidin activation by BMP6 can be modulated by each of the three hemochromatosis-associated proteins: HJV (hemojuvelin), HFE (hemochromatosis protein), and TfR2 (transferrin receptor 2), these proteins do not control the ALK5-mediated hepcidin response to TGF-β1. TGF-β1 mRNA levels are increased in mouse models of iron overload, indicating that TGF-β1 may contribute to hepcidin synthesis under these conditions. In conclusion, these data demonstrate that a complex regulatory network involving TGF-β1 and BMP6 may control the sensing of systemic and/or hepatic iron levels.

  9. Functional cooperation between Smad proteins and activator protein-1 regulates transforming growth factor-beta-mediated induction of endothelin-1 expression.

    PubMed

    Rodríguez-Pascual, Fernando; Redondo-Horcajo, Mariano; Lamas, Santiago

    2003-06-27

    Endothelin-1 (ET-1) is a 21-amino-acid potent vasoconstrictor peptide that is mainly produced by vascular endothelial cells. Expression of the ET-1 gene is subject to complex regulation by numerous factors, among which transforming growth factor-beta (TGF-beta) is one of the most important. It has been widely documented that TGF-beta increases ET-1 mRNA and peptide levels. We have explored the mechanism by which TGF-beta upregulates ET-1 expression in endothelial cells. Transcriptional activation of the ET-1 promoter accounted for the TGF-beta-induced increase in ET-1 mRNA levels. We have identified within the ET-1 promoter two DNA elements indispensable for TGF-beta-mediated induction of ET-1: an activator protein-1 (AP-1) site at -108/-102, known to be important for constitutive and induced expression, and a novel regulatory sequence located at -193/-171, which constitutes a specific binding site for Smad transcription factors. Mutation of both elements abolished TGF-beta responsiveness. Binding of Smad3/Smad4 and c-Jun to their corresponding DNA elements was evidenced by electrophoretic mobility shift assays. Furthermore, the coactivator CREB-binding protein (CBP)/p300 was found to play an essential role in the induction of the gene. The simultaneous requirement for two distinct and independent DNA elements suggests that Smads and activator protein-1 functionally cooperate through CBP/p300 to mediate TGF-beta-induced transcriptional activation of the ET-1 gene.

  10. Transforming growth factor-{beta} inhibits CCAAT/enhancer-binding protein expression and PPAR{gamma} activity in unloaded bone marrow stromal cells

    SciTech Connect

    Ahdjoudj, S.; Kaabeche, K.; Holy, X.; Fromigue, O.; Modrowski, D.; Zerath, E.; Marie, P.J. . E-mail: pierre.marie@larib.inserm.fr

    2005-02-01

    The molecular mechanisms regulating the adipogenic differentiation of bone marrow stromal cells in vivo remain largely unknown. In this study, we investigated the regulatory effects of transforming growth factor beta-2 (TGF-{beta}2) on transcription factors involved in adipogenic differentiation induced by hind limb suspension in rat bone marrow stromal cells in vivo. Time course real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR) analysis of gene expression showed that skeletal unloading progressively increases the expression of CCAAT/enhancer-binding protein (C/EBP){alpha} and C/EBP{beta} {alpha} at 5 days in bone marrow stromal cells resulting in increased peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}2) transcripts at 7 days. TGF-{beta}2 administration in unloaded rats corrected the rise in C/EBP{alpha} and C/EBP{beta} transcripts induced by unloading in bone marrow stromal cells. This resulted in inhibition of PPAR{gamma}2 expression that was associated with increased Runx2 expression. Additionally, the inhibition of C/EBP{alpha} and C/EBP{beta} expression by TGF-{beta}2 was associated with increased PPAR{gamma} serine phosphorylation in bone marrow stromal cells, a mechanism that inhibits PPAR{gamma} transactivating activity. The sequential inhibitory effect of TGF-{beta}2 on C/EBP{alpha}, C/EBP{beta}, and PPAR{gamma}2 resulted in reduced LPL expression and abolition of bone marrow stromal cell adipogenic differentiation, which contributed to prevent bone loss induced by skeletal unloading. We conclude that TGF-{beta}2 inhibits the excessive adipogenic differentiation of bone marrow stromal cells induced by skeletal unloading by inhibiting C/EBP{alpha}, C/EBP{beta}, and PPAR{gamma} expression and activity, which provides a sequential mechanism by which TGF-{beta}2 regulates adipogenic differentiation of bone marrow stromal cells in vivo.

  11. Thrombospondins selectively activate one of the two latent forms of transforming growth factor-beta present in adrenocortical cell-conditioned medium.

    PubMed

    Souchelnitskiy, S; Chambaz, E M; Feige, J J

    1995-11-01

    Transforming growth factor-beta (TGF beta) has been shown previously to be a potent inhibitor of bovine adrenocortical cell steroidogenic functions. However, it is present in the culture medium of these cells in a latent form. In this study, we analyzed in detail the biochemical composition of this latent TGF beta. Two distinct complexes could be separated chromatographically by gel filtration on Sephacryl S-300, and their composition was studied using immunochemical methods. The results indicate that one form (peak I) is a complex between alpha 2-macroglobulin (alpha 2M) and either the unprocessed TGF beta precursor or the mature form of TGF beta. In a major fraction of this complex, TGF beta is covalently linked to alpha 2 M, whereas in a minor fraction, it is noncovalently bound and, therefore, activatable. The second form of latent TGF beta (peak II) is a complex among latent TGF beta-binding protein (LTBP), latency-associated protein, and mature TGF beta and a complex between LTBP and unprocessed TGF beta. We investigated the ability of thrombospondins (TSP1 and TSP2) to activate these latent forms of TGF beta. TSP1 and TSP2 were equally potent at activating the LTBP-latency-associated protein-TGF beta complex in the absence of cell contact, but were ineffective on the alpha 2M-TGF beta complex. Therefore, TGF beta may act as an autocrine regulator of adrenocortical steroidogenic functions. Its activity appears to be controlled by TSPs, the local production of which is regulated by systemic ACTH.

  12. Lactic Acid is Elevated in Idiopathic Pulmonary Fibrosis and Induces Myofibroblast Differentiation Via pH-Dependent Activation of Transforming Growth Factor-β

    SciTech Connect

    Kottman, R. M.; Kulkarni, Ajit A.; Smolnycki, Katie A.; Lyda, Elizabeth; Dahanayake, Thinesh; Salibi, Rami; Honnons, Sylvie; Jones, Carolyn; Isern, Nancy G.; Hu, Jian Z.; Nathan, Steven D.; Grant, Geraldine; Phipps, Richard P.; Sime, Patricia J.

    2012-10-15

    Rationale: Idiopathic pulmonary fibrosis (IPF) is a complex disease for which the pathogenesis is poorly understood. In this study, we identified lactic acid as a metabolite that is elevated in the lung tissue of patients with IPF. Objectives: This study examines the effect of lactic acid on myofibroblast differentiation and pulmonary fibrosis. Methods:We used metabolomic analysis to examine cellular metabolism in lung tissuefrom patients with IPFanddeterminedthe effects of lactic acid and lactate dehydrogenase-5 (LDH5) overexpression on myofibroblast differentiation and transforming growth factor (TGF)-b activation in vitro. Measurements and Main Results: Lactic acid concentrations from healthy and IPF lung tissue were determined by nuclear magnetic resonance spectroscopy; a-smooth muscle actin, calponin, and LDH5 expression were assessed by Western blot of cell culture lysates. Lactic acid and LDH5 were significantly elevated in IPF lung tissue compared with controls. Physiologic concentrations of lactic acid induced myofibroblast differentiation via activation of TGF-b. TGF-b induced expression of LDH5 via hypoxia-inducible factor 1a (HIF1a). Importantly, overexpression of both HIF1a and LDH5 in human lung fibroblasts induced myofibroblast differentiation and synergized with low dose TGF-b to induce differentiation. Furthermore, inhibition of both HIF1a and LDH5 inhibited TGF-b–induced myofibroblast differentiation. Conclusions: We have identified the metabolite lactic acid as an important mediator of myofibroblast differentiation via a pHdependent activation of TGF-b. We propose that the metabolic milieu of the lung, and potentially other tissues, is an important driving force behind myofibroblast differentiation and potentially the initiation and progression of fibrotic disorders.

  13. Transcriptional activation of mouse mast cell Protease-7 by activin and transforming growth factor-beta is inhibited by microphthalmia-associated transcription factor.

    PubMed

    Funaba, Masayuki; Ikeda, Teruo; Murakami, Masaru; Ogawa, Kenji; Tsuchida, Kunihiro; Sugino, Hiromu; Abe, Matanobu

    2003-12-26

    Previous studies have revealed that activin A and transforming growth factor-beta1 (TGF-beta1) induced migration and morphological changes toward differentiation in bone marrow-derived cultured mast cell progenitors (BMCMCs). Here we show up-regulation of mouse mast cell protease-7 (mMCP-7), which is expressed in differentiated mast cells, by activin A and TGF-beta1 in BMCMCs, and the molecular mechanism of the gene induction of mmcp-7. Smad3, a signal mediator of the activin/TGF-beta pathway, transcriptionally activated mmcp-7. Microphthalmia-associated transcription factor (MITF), a tissue-specific transcription factor predominantly expressed in mast cells, melanocytes, and heart and skeletal muscle, inhibited Smad3-mediated mmcp-7 transcription. MITF associated with Smad3, and the C terminus of MITF and the MH1 and linker region of Smad3 were required for this association. Complex formation between Smad3 and MITF was neither necessary nor sufficient for the inhibition of Smad3 signaling by MITF. MITF inhibited the transcriptional activation induced by the MH2 domain of Smad3. In addition, MITF-truncated N-terminal amino acids could associate with Smad3 but did not inhibit Smad3-mediated transcription. The level of Smad3 was decreased by co-expression of MITF but not of dominant-negative MITF, which resulted from proteasomal protein degradation. The changes in the level of Smad3 protein were paralleled by those in Smad3-mediated signaling activity. These findings suggest that MITF negatively regulates Smad-dependent activin/TGF-beta signaling in a tissue-specific manner.

  14. Astragalus and Paeoniae Radix Rubra extract (APE) inhibits hepatic stellate cell activation by modulating transforming growth factor-β/smad pathway

    PubMed Central

    HUANG, WEIJUAN; LI, LIN; TIAN, XIAOPENG; YAN, JINJIN; YANG, XINZHENG; WANG, XINLONG; LIAO, GUOZHEN; QIU, GENQUAN

    2015-01-01

    Previous studies have shown that Astragalus and Paeoniae Radix Rubra extract (APE) is capable of protecting against liver fibrosis in rats. The hypothesis of the present study was that APE exerts its anti-fibrotic effect by mediating the transforming growth factor β (TGF-β)/Smad signaling pathway. In order to investigate this hypothesis, a series of assays were designed to detect the effects of APE on cell proliferation, cell invasion and the activation of hepatic stellate cells (HSCs). In addition, the effects of APE on the TGF-β/Smad signaling pathway were explored, with the aim of elucidating the underlying mechanisms. HSCs were initially isolated from normal rat liver. A number of assays were then employed in order to evaluate the effects of APE on the function of these cells. Cell proliferation was investigated using an MTT assay and cell invasion was observed with the use of transwell invasion chambers. Collagen synthesis was measured with a 3H-proline incorporation assay and expression of α-smooth muscle actin was used to determine the extent of HSC activation. Protein expression induced by TGF-β1 in HSCs was investigated by western blot and immunofluorescence analyses. Plasminogen activator inhibitor type1 (PAI-1) and urokinase-type plasminogen activator (uPA) transcriptional activity was measured using reverse transcription polymerase chain reaction. The results demonstrated that APE (5–80 μg/ml) significantly inhibited fetal bovine serum-induced cell proliferation in a dose-dependent manner. Cell invasion and activation of HSCs induced by TGF-β1 were disrupted by treatment with APE in a dose-dependent manner. TGF-β1 was observed to increase the phosphorylation of Smad2/3, while APE administered at higher doses produced inhibitory effects on Smad2/3 phosphorylation. In addition, administration of APE abrogated the TGF-β1-induced reduction in Smad-7 expression in a dose-dependent manner. The results further indicated that APE treatment not only

  15. Angiotensin II-induced pro-fibrotic effects require p38MAPK activity and transforming growth factor beta 1 expression in skeletal muscle cells.

    PubMed

    Morales, María Gabriela; Vazquez, Yaneisi; Acuña, María José; Rivera, Juan Carlos; Simon, Felipe; Salas, José Diego; Alvarez Ruf, Joel; Brandan, Enrique; Cabello-Verrugio, Claudio

    2012-11-01

    Fibrotic disorders are typically characterised by excessive connective tissue and extracellular matrix (ECM) deposition that preclude the normal healing of different tissues. Several skeletal muscle dystrophies are characterised by extensive fibrosis. Among the factors involved in skeletal muscle fibrosis is angiotensin II (Ang-II), a key protein of the renin-angiotensin system (RAS). We previously demonstrated that myoblasts responded to Ang-II by increasing the ECM protein levels mediated by AT-1 receptors, implicating an Ang-II-induced reactive oxygen species (ROS) by a NAD(P)H oxidase-dependent mechanism. In this paper, we show that in myoblasts, Ang-II induced the increase of transforming growth factor beta 1 (TGF-β1) and connective tissue growth factor (CTGF) expression through its AT-1 receptor. This effect is dependent of the NAD(P)H oxidase (NOX)-induced ROS, as indicated by a decrease of the expression of both pro-fibrotic factors when the ROS production was inhibited via the NOX inhibitor apocynin. The increase in pro-fibrotic factors levels was paralleled by enhanced p38MAPK and ERK1/2 phosphorylation in response to Ang-II. However, only the p38MAPK activity was critical for the Ang-II-induced fibrotic effects, as indicated by the decrease in the Ang-II-induced TGF-β1 and CTGF expression and fibronectin levels by SB-203580, an inhibitor of the p38MAPK, but not by U0126, an inhibitor of ERK1/2 phosphorylation. Furthermore, we showed that the Ang-II-dependent p38MAPK activation, but not the ERK1/2 phosphorylation, was necessary for the NOX-derived ROS. In addition, we demonstrated that TGF-β1 expression was required for the Ang-II-induced pro-fibrotic effects evaluated by using SB-431542, an inhibitor of TGF-βRI kinase activity, and by knocking down TGF-β1 levels by shRNA technique. These results strongly suggest that the fibrotic response to Ang-II is mediated by the AT-1 receptor and requires the p38MAPK phosphorylation, NOX-induced ROS, and TGF

  16. Inhibition of liver fibrosis by solubilized coenzyme Q10: Role of Nrf2 activation in inhibiting transforming growth factor-beta1 expression

    SciTech Connect

    Choi, Hoo-Kyun; Pokharel, Yuba Raj; Lim, Sung Chul; Han, Hyo-Kyung; Ryu, Chang Seon; Kim, Sang Kyum; Kwak, Mi Kyong; Kang, Keon Wook

    2009-11-01

    Coenzyme Q10 (CoQ10), an endogenous antioxidant, is important in oxidative phosphorylation in mitochondria. It has anti-diabetic and anti-cardiovascular disease effects, but its ability to protect against liver fibrosis has not been studied. Here, we assessed the ability of solubilized CoQ10 to improve dimethylnitrosamine (DMN)-induced liver fibrogenesis in mice. DMN treatments for 3 weeks produced a marked liver fibrosis as assessed by histopathological examination and tissue 4-hydroxyproline content. Solubilized CoQ10 (10 and 30 mg/kg) significantly inhibited both the increases in fibrosis score and 4-hydroxyproline content induced by DMN. Reverse transcription-polymerase chain reaction and Western blot analyses revealed that solubilized CoQ10 inhibited increases in the transforming growth factor-beta1 (TGF-beta1) mRNA and alpha-smooth muscle actin (alpha-SMA) protein by DMN. Interestingly, hepatic glutamate-cysteine ligase (GCL) and glutathione S-transferase A2 (GSTA2) were up-regulated in mice treated with CoQ10. Solubilized CoQ10 also up-regulated antioxidant enzymes such as catalytic subunits of GCL and GSTA2 via activating NF-E2 related factor2 (Nrf2)/antioxidant response element (ARE) in H4IIE hepatoma cells. Moreover, CoQ10's inhibition of alpha-SMA and TGF-beta1 expressions disappeared in Nrf2-null MEF cells. In contrast, Nrf2 overexpression significantly decreased the basal expression levels of alpha-SMA and TGF-beta1 in Nrf2-null MEF cells. These results demonstrated that solubilized CoQ10 inhibited DMN-induced liver fibrosis through suppression of TGF-beta1 expression via Nrf2/ARE activation.

  17. 2-Amino-3-methylimidazo[4,5-f]quinoline (IQ) promotes mouse hepatocarcinogenesis by activating transforming growth factor-β and Wnt/β-catenin signaling pathways.

    PubMed

    Xie, Xiao-Li; Wei, Min; Kakehashi, Anna; Yamano, Shotaro; Tajiri, Masaki; Wanibuchi, Hideki

    2012-02-01

    The purposes of the present study were to investigate the modifying effects of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), a genotoxic carcinogen produced during cooking of protein-rich foods, and elucidate underlying mechanisms in a two-stage hepatocarcinogenesis mice model. Six-week-old B6C3F1 mice were subjected to two-thirds partial hepatectomy at the beginning of the study, followed by an intraperitoneal injection of diethylnitrosamine on day 1. Starting 1 week later, they were fed diets containing IQ at doses of 30, 100, or 300 ppm for 39 weeks. A dose-dependent trend for increase in eosinophilic altered foci as well as eosinophilic hepatocellular adenomas was observed, along with significant elevation in the incidence of hepatocellular carcinomas in the 100- and 300-ppm IQ groups as compared with initiation control group. Furthermore, IQ elevated the protein expression levels of Wnt1, transforming growth factor-β (TGF-β), TGF-β receptors 1 and 2 (TβR1 and TβR2), and phosphorylated c-Jun (p-c-Jun), while suppressing those of E-cadherin and p21(WAF1/Cip1). Moreover, translocation of β-catenin to the nuclei as well as upregulated nuclear expression of c-Myc and cyclin D1, which are downstream targets of β-catenin and p-c-Jun, were detected at 100 and 300 ppm. These findings suggest that IQ exerts dose-dependent promoting effects on mice hepatocarcinogenesis by activating TGF-β and Wnt/β-catenin signaling pathways and inhibiting cell adhesion.

  18. Phase transformation and growth of hygroscopic aerosols

    SciTech Connect

    Tang, I.N.

    1995-09-01

    Ambient aerosols frequently contain large portions of hygroscopic inorganic salts such as chlorides, nitrates, and sulfates in either pure or mixed forms. Such inorganic salt aerosols exhibit the properties of deliquescence and efflorescence in air. The phase transformation from a solid particle to a saline droplet usually occurs spontaneously when the relative humidity of the atmosphere reaches a level specific to the chemical composition of the aerosol particle. Conversely, when the relative humidity decreases and becomes low enough, the saline droplet will evaporate and suddenly crystallize, expelling all its water content. The phase transformation and growth of aerosols play an important role in many atmospheric processes affecting air quality, visibility degradation, and climate changes. In this chapter, an exposition of the underlying thermodynamic principles is given, and recent advances in experimental methods utilizing single-particle levitation are discussed. In addition, pertinent and available thermodynamic data, which are needed for predicting the deliquescence properties of single and multi-component aerosols, are compiled. This chapter is useful to research scientists who are either interested in pursuing further studies of aerosol thermodynamics, or required to model the dynamic behavior of hygroscopic aerosols in a humid environment.

  19. Opposite and independent actions of cyclic AMP and transforming growth factor beta in the regulation of type 1 plasminogen activator inhibitor expression.

    PubMed Central

    Thalacker, F W; Nilsen-Hamilton, M

    1992-01-01

    We have investigated the mechanisms by which type 1 plasminogen activator inhibitor (PAI-1) is regulated by transforming growth factor beta (TGF-beta) and by epidermal growth factor (EGF) in CCL64 mink lung epithelial cells, BSC-1 monkey kidney epithelial cells, mouse embryo fibroblast (AKR-2B 84A) cells and normal rat kidney fibroblasts (NRK). TGF-beta increases PAI-1 expression in all four cell lines, and EGF acts synergistically with TGF-beta to increase PAI-1 expression in CCL64 cells but not in the other three cell lines. Here we show that PAI-1 expression can be regulated independently through two different signal transduction pathways. One pathway involves protein kinase C and is stimulated by the tumour promoter phorbol myristate acetate (PMA). Whereas preincubation with PMA completely eliminated PMA-induced PAI-1 synthesis and secretion in both CCL64 and BSC-1 cells, this treatment had no effect on TGF-beta- and EGF-induced PAI-1 levels. Therefore we conclude that protein kinase C does not mediate the effects of either EGF or TGF-beta on PAI-1 expression. The expression of PAI-1 was decreased by agents increasing intracellular cyclic AMP: (cAMP) cholera toxin, forskolin and dibutyryl cAMP lowered both the basal level and the TGF-beta- and PMA-induced levels of PAI-1 expression. These effects of cAMP-elevating agents and of TGF-beta on PAI-1 protein synthesis were also reflected in changes in TGF-beta-induced PAI-1 gene transcription, as measured by nuclear run-on. These results show that PAI-1 gene expression is sensitive to high levels of intracellular cAMP and that this effect occurs at the transcriptional level. Although increased intracellular cAMP concentrations decrease the absolute level of PAI-1 expression, the ability of TGF-beta and EGF to induce PAI-1 gene expression is unchanged. These results are discussed in relation to the observation that sensitivity to cAMP is a common feature of TGF-beta-regulated genes. Images Fig. 1. Fig. 2. Fig. 3. Fig

  20. Role of Flightless-I (Drosophila) homolog in the transcription activation of type I collagen gene mediated by transforming growth factor beta

    SciTech Connect

    Lim, Mi-Sun; Jeong, Kwang Won

    2014-11-21

    Highlights: • FLII activates TGFβ-mediated expression of COL1A2 gene. • TGFβ induces the association of FLII with SMAD3 and BRG1 in A549 cells. • FLII is required for the recruitment of SWI/SNF complex and chromatin accessibility to COL1A2 promoter. - Abstract: Flightless-I (Drosophila) homolog (FLII) is a nuclear receptor coactivator that is known to interact with other transcriptional regulators such as the SWI/SNF complex, an ATP-dependent chromatin-remodeling complex, at the promoter or enhancer region of estrogen receptor (ER)-α target genes. However, little is known about the role of FLII during transcription initiation in the transforming growth factor beta (TGFβ)/SMAD-dependent signaling pathway. Here, we demonstrate that FLII functions as a coactivator in the expression of type I collagen gene induced by TGFβ in A549 cells. FLII activates the reporter gene driven by COL1A2 promoter in a dose-dependent manner. Co-expression of GRIP1, CARM1, or p300 did not show any synergistic activation of transcription. Furthermore, the level of COL1A2 expression correlated with the endogenous level of FLII mRNA level. Depletion of FLII resulted in a reduction of TGFβ-induced expression of COL1A2 gene. In contrast, over-expression of FLII caused an increase in the endogenous expression of COL1A2. We also showed that FLII is associated with Brahma-related gene 1 (BRG1) as well as SMAD in A549 cells. Notably, the recruitment of BRG1 to the COL1A2 promoter region was decreased in FLII-depleted A549 cells, suggesting that FLII is required for TGFβ-induced chromatin remodeling, which is carried out by the SWI/SNF complex. Furthermore, formaldehyde-assisted isolation of regulatory elements (FAIRE)-quantitative polymerase chain reaction (qPCR) experiments revealed that depletion of FLII caused a reduction in chromatin accessibility at the COL1A2 promoter. These results suggest that FLII plays a critical role in TGFβ/SMAD-mediated transcription of the COL1A2 gene

  1. Interferon-gamma and transforming growth factor-beta modulate the activation of mitogen-activated protein kinases and tumor necrosis factor-alpha production induced by Fc gamma-receptor stimulation in murine macrophages.

    PubMed

    Rose, D M; Winston, B W; Chan, E D; Riches, D W; Henson, P M

    1997-09-08

    Engagement of receptors for the Fc region of IgG (Fc gamma R) can activate a variety of biological responses in macrophages, and these responses can be modulated either positively or negatively by co-stimulation with a variety of agents including cytokines such as interferon-gamma (IFN-gamma) and transforming growth factor-beta (TGF-beta). We have previously demonstrated that Fc gamma R crosslinking activates the mitogen-activated protein kinase (MAPK) family members p42MAPK, p38, and JNK. Herein, we examined the modulatory effect of IFN-gamma, TGF-beta, and platelet-activating factor (PAF) on Fc gamma R-induced MAPK activation in murine macrophages. Fc gamma R-induced activation of p42MAPK and JNK was augmented nearly two-fold by pretreatment with IFN-gamma. Conversely, TGF-beta pretreatment suppressed Fc gamma R-induced activation of p42MAPK, JNK, and p38. These modulatory effects of IFN-gamma and TGF-beta on MAPK activation correlated with changes in Fc gamma R-stimulated TNF-alpha production by these two cytokines.

  2. Whey protein concentrate enhances intestinal integrity and influences transforming growth factor-β1 and mitogen-activated protein kinase signalling pathways in piglets after lipopolysaccharide challenge.

    PubMed

    Xiao, Kan; Jiao, Lefei; Cao, Shuting; Song, Zehe; Hu, Caihong; Han, Xinyan

    2016-03-28

    Whey protein concentrate (WPC) has been reported to have protective effects on the intestinal barrier. However, the molecular mechanisms involved are not fully elucidated. Transforming growth factor-β1 (TGF-β1) is an important component in the WPC, but whether TGF-β1 plays a role in these processes is not clear. The aim of this study was to investigate the protective effects of WPC on the intestinal epithelial barrier as well as whether TGF-β1 is involved in these protection processes in a piglet model after lipopolysaccharide (LPS) challenge. In total, eighteen weanling pigs were randomly allocated to one of the following three treatment groups: (1) non-challenged control and control diet; (2) LPS-challenged control and control diet; (3) LPS+5 %WPC diet. After 19 d of feeding with control or 5 %WPC diets, pigs were injected with LPS or saline. At 4 h after injection, pigs were killed to harvest jejunal samples. The results showed that WPC improved (P<0·05) intestinal morphology, as indicated by greater villus height and villus height:crypt depth ratio, and intestinal barrier function, which was reflected by increased transepithelial electrical resistance and decreased mucosal-to-serosal paracellular flux of dextran (4 kDa), compared with the LPS group. Moreover, WPC prevented the LPS-induced decrease (P<0·05) in claudin-1, occludin and zonula occludens-1 expressions in the jejunal mucosae. WPC also attenuated intestinal inflammation, indicated by decreased (P<0·05) mRNA expressions of TNF-α, IL-6, IL-8 and IL-1β. Supplementation with WPC also increased (P<0·05) TGF-β1 protein, phosphorylated-Smad2 expression and Smad4 and Smad7 mRNA expressions and decreased (P<0·05) the ratios of the phosphorylated to total c-jun N-terminal kinase (JNK) and p38 (phospho-JNK:JNK and p-p38:p38), whereas it increased (P<0·05) the ratio of extracellular signal-regulated kinase (ERK) (phospho-ERK:ERK). Collectively, these results suggest that dietary inclusion of WPC

  3. Phase transformation and growth of hygroscopic aerosols

    SciTech Connect

    Tang, I.N.

    1999-11-01

    Ambient aerosols play an important role in many atmospheric processes affecting air quality, visibility degradation, and climatic changes as well. Both natural and anthropogenic sources contribute to the formation of ambient aerosols, which are composed mostly of sulfates, nitrates, and chlorides in either pure or mixed forms. These inorganic salt aerosols are hygroscopic by nature and exhibit the properties of deliquescence and efflorescence in humid air. For pure inorganic salt particles with diameter larger than 0.1 micron, the phase transformation from a solid particle to a saline droplet occurs only when the relative humidity in the surrounding atmosphere reaches a certain critical level corresponding to the water activity of the saturated solution. The droplet size or mass in equilibrium with relative humidity can be calculated in a straightforward manner from thermodynamic considerations. For aqueous droplets 0.1 micron or smaller, the surface curvature effect on vapor pressure becomes important and the Kelvin equation must be used.

  4. Transforming growth factor beta1 and aldosterone

    PubMed Central

    Matsuki, Kota; Hathaway, Catherine K.; Chang, Albert S.; Smithies, Oliver; Kakoki, Masao

    2016-01-01

    Purpose of review It is well established that blocking renin-angiotensin II-aldosterone system (RAAS) is effective for the treatment of cardiovascular and renal complications in hypertension and diabetes mellitus. Although the induction of transforming growth factor beta1 (TGFbeta1) by components of RAAS mediates the hypertrophic and fibrogenic changes in cardiovascular-renal complications, it is still controversial as to whether TGFbeta1 can be a target to prevent such complications. Here we review recent findings on the role of TGFbeta1 in fluid homeostasis, focusing on the relationship with aldosterone. Recent findings TGFbeta1 suppresses adrenal production of aldosterone and renal tubular sodium reabsorption. We have generated mice with TGFbeta1 mRNA expression graded in five steps from 10% to 300% normal, and found that blood pressure and plasma volume are negatively regulated by TGFbeta1. Notably, the 10 % hypomorph exhibits primary aldosteronism and sodium and water retention due to markedly impaired urinary excretion of water and electrolytes. Summary These results identify TGFbeta signaling as an important counterregulatory system against aldosterone. Understanding the molecular mechanisms for the suppressive effects of TGFbeta1 on adrenocortical and renal function may further our understanding of primary aldosteronism as well as assist in the development of novel therapeutic strategies for hypertension. PMID:25587902

  5. Isolation, semisynthesis, covalent docking and transforming growth factor beta-activated kinase 1 (TAK1)-inhibitory activities of (5Z)-7-oxozeaenol analogues.

    PubMed

    Fakhouri, Lara; El-Elimat, Tamam; Hurst, Dow P; Reggio, Patricia H; Pearce, Cedric J; Oberlies, Nicholas H; Croatt, Mitchell P

    2015-11-01

    (5Z)-7-Oxozeanol and related analogues were isolated and screened to explore their activity as TAK1 inhibitors. Seven analogues were synthesized and more than a score of natural products isolated that examined the role that different areas of the molecule contribute to TAK1 inhibition. A novel nonaromatic difluoro-derivative was synthesized that had similar potency compared to the lead. This is the first example of a nonaromatic compound in this class to have TAK1 inhibition. Covalent docking for the isolated and synthesized analogues was carried out and found a strong correlation between the observed activities and the calculated binding.

  6. PDGF-D promotes cell growth, aggressiveness, angiogenesis and EMT transformation of colorectal cancer by activation of Notch1/Twist1 pathway.

    PubMed

    Chen, Jinhuang; Yuan, Wenzheng; Wu, Liang; Tang, Qiang; Xia, Qinghua; Ji, Jintong; Liu, Zhengyi; Ma, Zhijun; Zhou, Zili; Cheng, Yifeng; Shu, Xiaogang

    2017-02-07

    Platelet-derived growth factor-D (PDGF-D) plays a crucial role in the progression of several cancers. However, its role in colorectal cancer (CRC) remains unclear. Our study showed that PDGF-D was highly expressed in CRC tissues and was positively associated with the clinicopathological features. Down-regulation of PDGF-D inhibited the tumor growth, migration and angiogenesis of SW480 cells in vitro and in vivo. Whereas up-regulation of PDGF-D promoted the malignant behaviors of HCT116 cells. Moreover, PDGF-D up-regulated the expression of Notch1 and Twist1 in CRC cells. In addition, PDGF-D expression promoted Epithelial to mesenchymal transition (EMT), which was accompanied with decreased E-cadherin and increased Vimentin expression. Consistently, PDGF-D, Notch1, and Twist1 are obviously up-regulated in transforming growth factor-beta 1 (TGF-β1) treated HCT116 cells. Since Notch1 and Twist1 play an important role in EMT and tumor progression, we examined whether there is a correlation between Notch1 and Twist1 in EMT status. Our results showed that up-regulation of Notch1 was able to rescue the effects of PDGF-D down-regulation on Twist1 expression in SW480 cells, whereas down-regulation of Notch1 reduced Twist1 expression in HCT116 cells. Furthermore, we found that Twist1 promoted EMT and aggressiveness of CRC cells. These results suggest that PDGF-D promotes tumor growth and aggressiveness of CRC, moreover, down-regulation of PDGF-D inactivates Notch1/Twist1 axis, which could reverse EMT and prevent CRC progression.

  7. Disruption of transforming growth factor-beta signaling through beta-spectrin ELF leads to hepatocellular cancer through cyclin D1 activation.

    PubMed

    Kitisin, K; Ganesan, N; Tang, Y; Jogunoori, W; Volpe, E A; Kim, S S; Katuri, V; Kallakury, B; Pishvaian, M; Albanese, C; Mendelson, J; Zasloff, M; Rashid, A; Fishbein, T; Evans, S R T; Sidawy, A; Reddy, E P; Mishra, B; Johnson, L B; Shetty, K; Mishra, L

    2007-11-01

    Transforming growth factor-beta (TGF-beta) signaling members, TGF-beta receptor type II (TBRII), Smad2, Smad4 and Smad adaptor, embryonic liver fodrin (ELF), are prominent tumor suppressors in gastrointestinal cancers. Here, we show that 40% of elf(+/-) mice spontaneously develop hepatocellular cancer (HCC) with markedly increased cyclin D1, cyclin-dependent kinase 4 (Cdk4), c-Myc and MDM2 expression. Reduced ELF but not TBRII, or Smad4 was observed in 8 of 9 human HCCs (P<0.017). ELF and TBRII are also markedly decreased in human HCC cell lines SNU-398 and SNU-475. Restoration of ELF and TBRII in SNU-398 cells markedly decreases cyclin D1 as well as hyperphosphorylated-retinoblastoma (hyperphosphorylated-pRb). Thus, we show that TGF-beta signaling and Smad adaptor ELF suppress human hepatocarcinogenesis, potentially through cyclin D1 deregulation. Loss of ELF could serve as a primary event in progression toward a fully transformed phenotype and could hold promise for new therapeutic approaches in human HCCs.

  8. Reduced surface expression of transforming growth factor beta receptor type II in mitogen-activated T cells from Sézary patients.

    PubMed Central

    Capocasale, R J; Lamb, R J; Vonderheid, E C; Fox, F E; Rook, A H; Nowell, P C; Moore, J S

    1995-01-01

    Sézary syndrome (SzS), the leukemic form of cutaneous T-cell lymphoma, is characterized by clonal proliferation of CD4+ T cells and immune dysfunctions, raising the possibility of cytokine-related abnormalities. We previously described a decreased response to the growth-inhibitory effects of transforming growth factor type beta (TGF-beta) in SzS T cells accompanied by apparent loss of surface type II TGF-beta receptor (TGF beta RII). To specifically determine if defects exist in TGF beta RII protein expression and/or transport in SzS patients, we developed a sensitive flow cytometric method to detect TGF beta RII on the surface and intracellularly in the CD4+ T cells. Our results indicate that unlike normal CD4+ T cells, CD4+ T cells from 9 of 12 SzS patients expressed little, if any, surface TGF beta RII in response to mitogen stimulation. At the intracellular level, however, pools of TGF beta RII were comparable to those in normal CD4+ T cells. This indicates that defective trafficking of this inhibitory cytokine receptor may contribute significantly to the development of this disease. Images Fig. 2 PMID:7777538

  9. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and PH domain and leucine-rich repeat phosphatase cross-talk (PHLPP) in cancer cells and in transforming growth factor β-activated stem cells.

    PubMed

    Ghalali, Aram; Ye, Zhi-Wei; Högberg, Johan; Stenius, Ulla

    2014-04-25

    Akt kinase controls cell survival, proliferation, and invasive growth and is a critical factor for cancer development. Here we describe a cross-talk between phosphatases that may preserve levels of activated/phosphorylated Akt and confer aggressive growth of cancer cells. In prostatic cancer cells, but not in non-transformed cells or in prostate stem cells, we found that the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) overexpression down-regulated PH domain and leucine-rich repeat phosphatase (PHLPP) and that PHLPP overexpression down-regulated PTEN. We also show that silencing PTEN by siRNA increased the levels of PHLPPs. This cross-talk facilitated invasive migration and was mediated by epigenetic alterations, including activation of miR-190, miR-214, polycomb group of proteins, as well as DNA methylation. A role for the purinergic receptor P2X4, previously associated with wound healing, was indicated. We also show that TGF-β1 induced cross-talk concomitant with epithelial-mesenchymal transition in stem cells. The cross-talk emerged as an integrated part of epithelial-mesenchymal transition. We conclude that cross-talk between PTEN and PHLPPs is silenced in normal prostate cells but activated in TGF-β1 transformed prostate stem and cancer cells and facilitates invasive growth.

  10. Mucin1 mediates autocrine transforming growth factor beta signaling through activating the c-Jun N-terminal kinase/activator protein 1 pathway in human hepatocellular carcinoma cells.

    PubMed

    Li, Qiongshu; Liu, Guomu; Shao, Dan; Wang, Juan; Yuan, Hongyan; Chen, Tanxiu; Zhai, Ruiping; Ni, Weihua; Tai, Guixiang

    2015-02-01

    In a previous study, we observed by global gene expression analysis that oncogene mucin1 (MUC1) silencing decreased transforming growth factor beta (TGF-β) signaling in the human hepatocellular carcinoma (HCC) cell line SMMC-7721. In this study, we report that MUC1 overexpression enhanced the levels of phosphorylated Smad3 linker region (p-Smad3L) (Ser-213) and its target gene MMP-9 in HCC cells, suggesting that MUC1 mediates TGF-β signaling. To investigate the effect of MUC1 on TGF-β signaling, we determined TGF-β secretion in MUC1 gene silencing and overexpressing cell lines. MUC1 expression enhanced not only TGF-β1 expression at the mRNA and protein levels but also luciferase activity driven by a TGF-β promoter, as well as elevated the activation of c-Jun N-terminal kinase (JNK) and c-Jun, a member of the activation protein 1 (AP-1) transcription factor family. Furthermore, pharmacological reduction of TGF-β receptor (TβR), JNK and c-Jun activity inhibited MUC1-induced autocrine TGF-β signaling. Moreover, a co-immunoprecipitation assay showed that MUC1 directly bound and activated JNK. In addition, both MUC1-induced TGF-β secretion and exogenous TGF-β1 significantly increased Smad signaling and cell migration, which were markedly inhibited by either TβR inhibitor or small interfering RNA silencing of TGF-β1 gene in HCC cells. The high correlation between MUC1 and TGF-β1 or p-Smad3L (Ser-213) expression was shown in tumor tissues from HCC patients by immunohistochemical staining analysis. Collectively, these results indicate that MUC1 mediates autocrine TGF-β signaling by activating the JNK/AP-1 pathway in HCC cells. Therefore, MUC1 plays a key role in HCC progression and could serve as an attractive target for HCC therapy.

  11. Human transforming growth factor. beta. -. cap alpha. /sub 2/-macroglobulin complex is a latent form of transforming growth factor. beta

    SciTech Connect

    Huang, S.S.; O'Grady, P.; Huang, J.S.

    1987-05-01

    Human platelet-derived transforming growth factor ..beta.. (TGF..beta..) has been shown to be present as a high molecular weight latent form in human serum. Appearance of transforming growth factor activity, along with the change from high molecular weight form to low molecular weight form, was observed following treatment of the latent form of TGF..beta.. with acid or urea, suggesting that the latent form of TGF..beta.. is a complex of TGF..beta.. and a high molecular weight binding protein. Human ..cap alpha../sub 2/-M has been found to be a plasma binding protein for platelet-derived growth factor (PDGF) in serum or plasma. TGF..beta.. and PDGF share similar properties. They, therefore, investigated the interaction between /sup 125/I-TGF..beta.. and ..cap alpha../sub 2/M. /sup 125/I-TGF..beta.. and purified human ..cap alpha../sub 2/M formed a complex as demonstrated by polyacrylamide gel electrophoresis. Most of the /sup 125/I-TGF..beta..-..cap alpha../sub 2/M complex could be dissociated by acid or urea treatment. These results suggest that ..cap alpha../sub 2/M is a binding protein for TGF..beta.. and that TGF..beta..-..cap alpha../sub 2/M complex may be the latent form of TGF..beta.. in serum.

  12. Role of growth factors in the growth of normal and transformed cells

    SciTech Connect

    Lokeshwar, V.B.

    1989-01-01

    Growth factors play an important role in the growth of normal cells. However, their untimely and/or excess production leads to neoplastic transformation. The role of growth factors in the growth of normal cells was studied by investigating the mechanism of transmodulation of the cell surface EGF receptor number by protamine. Protamine increased the EGF stimulated mitogenic response in Swiss mouse 3T3 cells and A431 cells by increasing the number of functionally active EGF receptors. Protamine also increased EGF receptor number in plasma membranes and solubilized membranes. This was evidenced by an increase in both {sup 125}I-EGF-EGF-receptor complex and EGF stimulated phosphorylation of the EGF receptor. The solubilized EGF receptor was retained on a protamine-agarose gel indicating that protamine might increase EGF receptor number by directly activating cryptic EGF receptors in the plasma membranes. The role of growth factors in neoplastic transformation was studied by investigating the role of the oncogene v-sis in the growth of Simian sarcoma virus (SSV) transformed cells. The product of the oncogene v-sis is 94% homologous to the B chain of PDGF. This study found that (i) v-sis gene product is synthesized as a 32 kDa unglycosylated monomer which is glycosylated, dimerized and proteolytically processed into p36, p72, p68, p58, p44 and p27 mol. wt. species respectively. (ii) p36, p72, p68 and p58 are very likely formed in the endoplasmic reticulum and/or Golgi complex. A fraction of newly synthesized p72, p68 and p58 is degraded intracellularly at a fast rate. (iii) p44 is a secretory product which remains tightly associated with the cell surface. p44 is recaptured by the cells through interaction with cell surface PDGF receptors and degraded into p27. (iv) During long term cultures p44 is extracellularly cleaved into a 27 kDa product.

  13. Cumulin, an Oocyte-secreted Heterodimer of the Transforming Growth Factor-β Family, Is a Potent Activator of Granulosa Cells and Improves Oocyte Quality*

    PubMed Central

    Mottershead, David G.; Sugimura, Satoshi; Al-Musawi, Sara L.; Li, Jing-Jie; Richani, Dulama; White, Melissa A.; Martin, Georgia A.; Trotta, Andrew P.; Ritter, Lesley J.; Shi, Junyan; Mueller, Thomas D.; Harrison, Craig A.; Gilchrist, Robert B.

    2015-01-01

    Growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are oocyte-specific growth factors with central roles in mammalian reproduction, regulating species-specific fecundity, ovarian follicular somatic cell differentiation, and oocyte quality. In the human, GDF9 is produced in a latent form, the mechanism of activation being an open question. Here, we produced a range of recombinant GDF9 and BMP15 variants, examined their in silico and physical interactions and their effects on ovarian granulosa cells (GC) and oocytes. We found that the potent synergistic actions of GDF9 and BMP15 on GC can be attributed to the formation of a heterodimer, which we have termed cumulin. Structural modeling of cumulin revealed a dimerization interface identical to homodimeric GDF9 and BMP15, indicating likely formation of a stable complex. This was confirmed by generation of recombinant heterodimeric complexes of pro/mature domains (pro-cumulin) and covalent mature domains (cumulin). Both pro-cumulin and cumulin exhibited highly potent bioactivity on GC, activating both SMAD2/3 and SMAD1/5/8 signaling pathways and promoting proliferation and expression of a set of genes associated with oocyte-regulated GC differentiation. Cumulin was more potent than pro-cumulin, pro-GDF9, pro-BMP15, or the two combined on GC. However, on cumulus-oocyte complexes, pro-cumulin was more effective than all other growth factors at notably improving oocyte quality as assessed by subsequent day 7 embryo development. Our results support a model of activation for human GDF9 dependent on cumulin formation through heterodimerization with BMP15. Oocyte-secreted cumulin is likely to be a central regulator of fertility in mono-ovular mammals. PMID:26254468

  14. Rapid Activation of Transforming Growth Factor β–Activated Kinase 1 in Chondrocytes by Phosphorylation and K63‐Linked Polyubiquitination Upon Injury to Animal Articular Cartilage

    PubMed Central

    Ismail, Heba M.; Didangelos, Athanasios; Vincent, Tonia L.

    2017-01-01

    Objective Mechanical injury to cartilage predisposes to osteoarthritis (OA). Wounding of the articular cartilage surface causes rapid activation of MAP kinases and NF‐κB, mimicking the response to inflammatory cytokines. This study was undertaken to identify the upstream signaling mechanisms involved. Methods Cartilage was injured by dissecting it from the articular surface of porcine metacarpophalangeal (MCP) joints or by avulsing murine proximal femoral epiphyses. Protein phosphorylation was assayed by Western blotting of cartilage lysates. Immunolocalization of phosphorylated activating transcription factor 2 (ATF‐2) and NF‐κB/p65 was detected by confocal microscopy. Messenger RNA (mRNA) was measured by quantitative reverse transcriptase–polymerase chain reaction (qRT‐PCR). Receptor associated protein 80 (RAP‐80) ubiquitin interacting motif agarose was used in a pull‐down assay to obtain K63‐polyubiquitinated proteins. Ubiquitin linkages on immunoprecipitated transforming growth factor β–activated kinase 1 (TAK‐1) were analyzed with deubiquitinases. Results Sharp injury to porcine cartilage caused rapid activation of JNK and NF‐κB pathways and the upstream kinases MKK‐4, IKK, and TAK‐1. Pharmacologic inhibition of TAK‐1 in porcine cartilage abolished JNK and NF‐κB activation and reduced the injury‐dependent inflammatory gene response. High molecular weight species of phosphorylated TAK‐1 were induced by injury, indicating its ubiquitination. An overall increase in K63‐linked polyubiquitination was detected upon injury, and TAK‐1 was specifically linked to K63‐ but not K48‐polyubiquitin chains. In mice, avulsion of wild‐type femoral epiphyses caused similar intracellular signaling that was reduced in cartilage‐specific TAK‐1–null mice. Epiphyseal cartilage of MyD88‐null and TRAF‐6–null mice responded to injury, suggesting the involvement of a ubiquitin E3 ligase other than TRAF‐6. Conclusion

  15. The latent transforming growth factor beta binding protein (LTBP) family.

    PubMed Central

    Oklü, R; Hesketh, R

    2000-01-01

    The transforming growth factor beta (TGFbeta) cytokines are a multi-functional family that exert a wide variety of effects on both normal and transformed mammalian cells. The secretion and activation of TGFbetas is regulated by their association with latency-associated proteins and latent TGFbeta binding proteins (LTBPs). Over the past few years, three members of the LTBP family have been identified, in addition to the protoype LTBP1 first sequenced in 1990. Three of the LTBP family are expressed in a variety of isoforms as a consequence of alternative splicing. This review summarizes the differences between the isoforms in terms of the effects on domain structure and hence possible function. The close identity between LTBPs and members of the fibrillin family, mutations in which have been linked directly to Marfan's syndrome, suggests that anomalous expression of LTBPs may be associated with disease. Recent data indicating that differential expression of LTBP1 isoforms occurs during the development of coronary heart disease is considered, together with evidence that modulation of LTBP function, and hence of TGFbeta activity, is associated with a variety of cancers. PMID:11104663

  16. Hydrogen peroxide inhibits transforming growth factor-β1-induced cell cycle arrest by promoting Smad3 linker phosphorylation through activation of Akt-ERK1/2-linked signaling pathway.

    PubMed

    Choi, Jiyeon; Park, Seong Ji; Jo, Eun Ji; Lee, Hui-Young; Hong, Suntaek; Kim, Seong-Jin; Kim, Byung-Chul

    2013-06-14

    Hydrogen peroxide (H2O2) functions as a second messenger in growth factor receptor-mediated intracellular signaling cascade and is tumorigenic by virtue of its ability to promote cell proliferation; however, the mechanisms underlying the growth stimulatory action of H2O2 are less understood. Here we report an important mechanism for antagonistic effects of H2O2 on growth inhibitory response to transforming growth factor-β1 (TGF-β1). In Mv1Lu and HepG2 cells, pretreatment of H2O2 (0.05-0.2 mM) completely blocked TGF-β1-mediated induction of p15(INK4B) expression and increase of its promoter activity. Interestingly, H2O2 selectively suppressed the transcriptional activation potential of Smad3, not Smad2, in the absence of effects on TGF-β1-induced phosphorylation of the COOH-tail SSXS motif of Smad3 and its nuclear translocation. Mechanism studies showed that H2O2 increases the phosphorylation of Smad3 at the middle linker region in a concentration- and time-dependent manner and this effect is mediated by activation of extracellular signal-activated kinase 1/2 through Akt. Furthermore, expression of a mutant Smad3 in which linker phosphorylation sites were ablated significantly abrogated the inhibitory effects of H2O2 on TGF-β1-induced increase of p15(INK4B)-Luc reporter activity and blockade of cell cycle progression from G1 to S phase. These findings for the first time define H2O2 as a signaling molecule that modulate Smad3 linker phosphorylation and its transcriptional activity, thus providing a potential mechanism whereby H2O2 antagonizes the cytostatic function of TGF-β1.

  17. A soluble factor from Trypanosoma cruzi inhibits transforming growth factor-ß-induced MAP kinase activation and gene expression in dermal fibroblasts.

    PubMed

    Mott, G Adam; Costales, Jaime A; Burleigh, Barbara A

    2011-01-01

    The protozoan parasite Trypanosoma cruzi, which causes human Chagas' disease, exerts a variety of effects on host extracellular matrix (ECM) including proteolytic degradation of collagens and dampening of ECM gene expression. Exposure of primary human dermal fibroblasts to live infective T. cruzi trypomastigotes or their shed/secreted products results in a rapid down-regulation of the fibrogenic genes collagenIα1, fibronectin and connective tissue growth factor (CTGF/CCN2). Here we demonstrate the ability of a secreted/released T. cruzi factor to antagonize ctgf/ccn2 expression in dermal fibroblasts in response to TGF-ß, lysophosphatidic acid or serum, where agonist-induced phosphorylation of the mitogen-activated protein (MAP) kinases Erk1/2, p38 and JNK was also inhibited. Global analysis of gene expression in dermal fibroblasts identified a discrete subset of TGF-ß-inducible genes involved in cell proliferation, wound repair, and immune regulation that are inhibited by T. cruzi secreted/released factors, where the genes exhibiting the highest sensitivity to T. cruzi are known to be regulated by MAP kinase-activated transcription factors. Consistent with this observation, the Ets-family transcription factor binding site in the proximal promoter region of the ctgf/ccn2 gene (-91 bp to -84 bp) was shown to be required for T. cruzi-mediated down-regulation of ctgf/ccn2 reporter expression. The cumulative data suggest a model in which T. cruzi-derived molecules secreted/released early in the infective process dampen MAP kinase signaling and the activation of transcription factors that regulate expression of fibroblast genes involved in wound repair and tissue remodelling, including ctgf/ccn2. These findings have broader implications for local modulation of ECM synthesis/remodelling by T. cruzi during the early establishment of infection in the mammalian host and highlight the potential for pathogen-derived molecules to be exploited as tools to modulate the

  18. Role of polypeptide growth factors in phenotypic transformation of normal rat kidney cells

    SciTech Connect

    van Zoelen, E.J.J.; van Oostwaard, T.M.J.; de Laat, S.W.

    1988-01-05

    A serum-free assay has been established for studying the role of polypeptide growth factors in inducing loss of density-dependent inhibition of growth of normal rat kidney (NRK) cells. The process has been characterized by measuring the time course of (/sup 3/H)thymidine incorporation into confluent, quiescent NRK cultures stimulated by defined polypeptide growth factors, in combination with cell counting studies, increases in DNA content, and cell cycle analysis by means of a fluorescence-activated cell sorter. It is shown that none of the growth factors tested is able to induce loss of density-dependent inhibition of growth by itself, but strong synergism was observed when combinations of growth factors were tested. None of the above factors was found to be essential, however, since any combination of three of the above four growth factors strongly induced the process. Strong parallels were observed between the growth factor requirements for inducing loss of density-dependent inhibition of growth under serum-free conditions and the requirements for induction of anchorage-independent proliferation under growth factor-defined assay conditions. This indicates that most likely the same cellular processes underlie these two aspects of phenotypic transformation, although data indicate that anchorage-independent proliferation may be a more restricted property of phenotypic transformation than loss of density dependence of proliferation. It is concluded that phenotypic transformation of NRK cells does not require specific polypeptide growth factors, but reflects the ability of these cells to respond to multiple growth factors.

  19. Transforming Growth Factor Beta, Bioenergetics and Mitochondria in Renal Disease

    PubMed Central

    Gabriella, Casalena; Ilse, Daehn; Erwin, Bottinger

    2012-01-01

    The transforming growth factor beta (TGF-β ) family is comprised of over 30 family members that are structurally related secreted dimeric cytokines, including TGF-β, activins, and bone morphogenetic proteins (BMPs)/growth and differentiation factors (GDFs). TGF-β are pluripotent regulators of cell proliferation, differentiation, apoptosis, migration, and adhesion of many different cell types. TGF-β pathways are highly evolutionarily conserved and control embryogenesis, tissue repair, and tissue homeostasis in invertebrates and vertebrates. Aberrations in TGF-β activity and signaling underlie a broad spectrum of developmental disorders and major pathologies in humans, including cancer, fibrosis and autoimmune diseases. Recent observations indicate an emerging role for TGF-β in regulation of mitochondrial bioenergetics and oxidative stress responses characteristic of chronic degenerative diseases and ageing. Conversely, energy and metabolic sensory pathways cross-regulate mediators of TGF-β signaling. Here we review TGF-β and regulation of bioenergetic and mitochondrial functions, including energy and oxidant metabolism and apoptotic cell death, as well as their emerging relevance in renal biology and disease. PMID:22835461

  20. Hydrogen peroxide inhibits transforming growth factor-β1-induced cell cycle arrest by promoting Smad3 linker phosphorylation through activation of Akt-ERK1/2-linked signaling pathway

    SciTech Connect

    Choi, Jiyeon; Park, Seong Ji; Jo, Eun Ji; Lee, Hui-Young; Hong, Suntaek; Kim, Seong-Jin; Kim, Byung-Chul

    2013-06-14

    Highlights: •H{sub 2}O{sub 2} inhibits TGF-β1-induced cell cycle arrest. •H{sub 2}O{sub 2} induces Smad3 linker phosphorylation through Akt-ERK1/2 pathway. •H{sub 2}O{sub 2}-mediated suppression of TGF-β signal requires Smad3 linker phosphorylation. •This is a first report about interplay between H{sub 2}O{sub 2} and growth inhibition pathway. -- Abstract: Hydrogen peroxide (H{sub 2}O{sub 2}) functions as a second messenger in growth factor receptor-mediated intracellular signaling cascade and is tumorigenic by virtue of its ability to promote cell proliferation; however, the mechanisms underlying the growth stimulatory action of H{sub 2}O{sub 2} are less understood. Here we report an important mechanism for antagonistic effects of H{sub 2}O{sub 2} on growth inhibitory response to transforming growth factor-β1 (TGF-β1). In Mv1Lu and HepG2 cells, pretreatment of H{sub 2}O{sub 2} (0.05–0.2 mM) completely blocked TGF-β1-mediated induction of p15{sup INK4B} expression and increase of its promoter activity. Interestingly, H{sub 2}O{sub 2} selectively suppressed the transcriptional activation potential of Smad3, not Smad2, in the absence of effects on TGF-β1-induced phosphorylation of the COOH-tail SSXS motif of Smad3 and its nuclear translocation. Mechanism studies showed that H{sub 2}O{sub 2} increases the phosphorylation of Smad3 at the middle linker region in a concentration- and time-dependent manner and this effect is mediated by activation of extracellular signal-activated kinase 1/2 through Akt. Furthermore, expression of a mutant Smad3 in which linker phosphorylation sites were ablated significantly abrogated the inhibitory effects of H{sub 2}O{sub 2} on TGF-β1-induced increase of p15{sup INK4B}-Luc reporter activity and blockade of cell cycle progression from G1 to S phase. These findings for the first time define H{sub 2}O{sub 2} as a signaling molecule that modulate Smad3 linker phosphorylation and its transcriptional activity, thus providing

  1. Effect of transforming growth factor-β1 on human intrahepatic cholangiocarcinoma cell growth

    PubMed Central

    Shimizu, Tetsuya; Yokomuro, Shigeki; Mizuguchi, Yoshiaki; Kawahigashi, Yutaka; Arima, Yasuo; Taniai, Nobuhiko; Mamada, Yasuhiro; Yoshida, Hiroshi; Akimaru, Koho; Tajiri, Takashi

    2006-01-01

    AIM: To elucidate the biological effects of transforming growth factor-β1 (TGF-β1) on intrahepatic cholan-giocarcinoma (ICC). METHODS: We investigated the effects of TGF-β1 on human ICC cell lines (HuCCT1, MEC, and HuH-28) by monitoring the influence of TGF-β1 on tumor growth and interleukin-6 (IL-6) expression in ICC cells. RESULTS: All three human ICC cell lines produced TGF-β1 and demonstrated accelerated growth in the presence of TGF-β1 with no apoptotic effect. Studies on HuCCT1 revealed a TGF-β1-induced stimulation of the expression of TGF-β1, as well as a decrease in TGF-β1 mRNA expression induced by neutralizing anti-TGF-β1 antibody. These results indicate that TGF-β1 stimulates the production and function of TGF-β1 in an autocrine fashion. Further, IL-6 secretion was observed in all three cell lines and exhibited an inhibitory response to neutralizing anti-TGF-β1 antibody. Experiments using HuCCT1 revealed a TGF-β1-induced acceleration of IL-6 protein expression and mRNA levels. These findings demonstrate a functional interaction between TGF-β1 and IL-6. All three cell lines proliferated in the presence of IL-6. In contrast, TGF-β1 induced no growth effect in HuCCT1 in the presence of small interfering RNA against a specific cell surface receptor of IL-6 and signal transducer and activator of transcription-3. CONCLUSION: ICC cells produce TGF-β1 and confer a TGF-β1-induced growth effect in an autocrine fashion. TGF-β1 activates IL-6 production, and the functional interaction between TGF-β1 and IL-6 contributes to ICC cell growth by TGF-β1. PMID:17072955

  2. Surface proteome analysis identifies platelet derived growth factor receptor-alpha as a critical mediator of transforming growth factor-beta-induced collagen secretion.

    PubMed

    Heinzelmann, Katharina; Noskovičová, Nina; Merl-Pham, Juliane; Preissler, Gerhard; Winter, Hauke; Lindner, Michael; Hatz, Rudolf; Hauck, Stefanie M; Behr, Jürgen; Eickelberg, Oliver

    2016-05-01

    Fibroblasts are extracellular matrix-producing cells in the lung. Fibroblast activation by transforming growth factor-beta leads to myofibroblast-differentiation and increased extracellular matrix deposition, a hallmark of pulmonary fibrosis. While fibroblast function with respect to migration, invasion, and extracellular matrix deposition has been well-explored, little is known about the surface proteome of lung fibroblasts in general and its specific response to fibrogenic growth factors, in particular transforming growth factor-beta. We thus performed a cell-surface proteome analysis of primary human lung fibroblasts in presence/absence of transforming growth factor-beta, followed by characterization of our findings using FACS analysis, Western blot, and siRNA-mediated knockdown experiments. We identified 213 surface proteins significantly regulated by transforming growth factor-beta, platelet derived growth factor receptor-alpha being one of the top down-regulated proteins. Transforming growth factor beta-induced downregulation of platelet derived growth factor receptor-alpha induced upregulation of platelet derived growth factor receptor-beta expression and phosphorylation of Akt, a downstream target of platelet derived growth factor signaling. Importantly, collagen type V expression and secretion was strongly increased after forced knockdown of platelet derived growth factor receptor-alpha, an effect that was potentiated by transforming growth factor-beta. We therefore show previously underappreciated cross-talk of transforming growth factor-beta and platelet derived growth factor signaling in human lung fibroblasts, resulting in increased extracellular matrix deposition in a platelet derived growth factor receptor-alpha dependent manner. These findings are of particular importance for the treatment of lung fibrosis patients with high pulmonary transforming growth factor-beta activity.

  3. Transforming Growth Factor-B Receptors in Human Breast Cancer.

    DTIC Science & Technology

    1998-05-01

    receptor. Nature 370:341-347,1994 60. Wang T, Donahoe P, Zervos AS: Specific interaction of type I receptors of the TGFß family with the immunophilin...Res 56: 44^48,1996 82. Kadin ME. Cavaille-Coll MW, Gertz R. Massague J, Chei- fetz S. George D: Loss of receptors for transforming growth factor ß

  4. Toxoplasma gondii Prevents Neuron Degeneration by Interferon-γ-Activated Microglia in a Mechanism Involving Inhibition of Inducible Nitric Oxide Synthase and Transforming Growth Factor-β1 Production by Infected Microglia

    PubMed Central

    Rozenfeld, Claudia; Martinez, Rodrigo; Seabra, Sérgio; Sant’Anna, Celso; Gonçalves, J. Gabriel R.; Bozza, Marcelo; Moura-Neto, Vivaldo; De Souza, Wanderley

    2005-01-01

    Interferon (IFN)-γ, the main cytokine responsible for immunological defense against Toxoplasma gondii, is essential in all infected tissues, including the central nervous system. However, IFN-γ-activated microglia may cause tissue injury through production of toxic metabolites such as nitric oxide (NO), a potent inducer of central nervous system pathologies related to inflammatory neuronal disturbances. Despite potential NO toxicity, neurodegeneration is not commonly found during chronic T. gondii infection. In this study, we describe decreased NO production by IFN-γ-activated microglial cells infected by T. gondii. This effect involved strong inhibition of iNOS expression in IFN-γ-activated, infected microglia but not in uninfected neighboring cells. The inhibition of NO production and iNOS expression were parallel with recovery of neurite outgrowth when neurons were co-cultured with T. gondii-infected, IFN-γ-activated microglia. In the presence of transforming growth factor (TGF)-β1-neutralizing antibodies, the beneficial effect of the parasite on neurons was abrogated, and NO production reverted to levels similar to IFN-γ-activated uninfected co-cultures. In addition, we observed Smad-2 nuclear translocation, a hallmark of TGF-β1 downstream signaling, in infected microglial cultures, emphasizing an autocrine effect restricted to infected cells. Together, these data may explain a neuropreservation pattern observed during immunocompetent host infection that is dependent on T. gondii-triggered TGF-β1 secretion by infected microglia. PMID:16192637

  5. Transforming growth factor-{beta}-inducible phosphorylation of Smad3.

    PubMed

    Wang, Guannan; Matsuura, Isao; He, Dongming; Liu, Fang

    2009-04-10

    Smad proteins transduce the transforming growth factor-beta (TGF-beta) signal at the cell surface into gene regulation in the nucleus. Upon TGF-beta treatment, the highly homologous Smad2 and Smad3 are phosphorylated by the TGF-beta receptor at the SSXS motif in the C-terminal tail. Here we show that in addition to the C-tail, three (S/T)-P sites in the Smad3 linker region, Ser(208), Ser(204), and Thr(179) are phosphorylated in response to TGF-beta. The linker phosphorylation peaks at 1 h after TGF-beta treatment, behind the peak of the C-tail phosphorylation. We provide evidence suggesting that the C-tail phosphorylation by the TGF-beta receptor is necessary for the TGF-beta-induced linker phosphorylation. Although the TGF-beta receptor is necessary for the linker phosphorylation, the receptor itself does not phosphorylate these sites. We further show that ERK is not responsible for TGF-beta-dependent phosphorylation of these three sites. We show that GSK3 accounts for TGF-beta-inducible Ser(204) phosphorylation. Flavopiridol, a pan-CDK inhibitor, abolishes TGF-beta-induced phosphorylation of Thr(179) and Ser(208), suggesting that the CDK family is responsible for phosphorylation of Thr(179) and Ser(208) in response to TGF-beta. Mutation of the linker phosphorylation sites to nonphosphorylatable residues increases the ability of Smad3 to activate a TGF-beta/Smad-target gene as well as the growth-inhibitory function of Smad3. Thus, these observations suggest that TGF-beta-induced phosphorylation of Smad3 linker sites inhibits its antiproliferative activity.

  6. Transforming growth factor β signaling in uterine development and function.

    PubMed

    Li, Qinglei

    2014-01-01

    Transforming growth factor β (TGFβ) superfamily is evolutionarily conserved and plays fundamental roles in cell growth and differentiation. Mounting evidence supports its important role in female reproduction and development. TGFBs1-3 are founding members of this growth factor family, however, the in vivo function of TGFβ signaling in the uterus remains poorly defined. By drawing on mouse and human studies as a main source, this review focuses on the recent progress on understanding TGFβ signaling in the uterus. The review also considers the involvement of dysregulated TGFβ signaling in pathological conditions that cause pregnancy loss and fertility problems in women.

  7. Partially transformed, anchorage-independent human diploid fibroblasts result from overexpression of the c-sis oncogene: Mitogenic activity of an apparent monomeric platelet-derived growth factor 2 species

    SciTech Connect

    Stevens, C.W.; Brondyk, W.H.; Burgess, J.A.; Manoharan, T.H.; Hane, B.G.; Fahl, W.E.

    1988-05-01

    A human c-sis cDNA in an expression vector was introduced into human diploid fibroblasts by transfection or electroporation. Fibroblast clones showing an aberrant, densely packed colony morphology were isolated and found to overexpress a 3.6-kilobase sis mRNA species and associated immunoprecipitable platelet-derived growth factor (PDGF) 2 proteins. Parallel analyses in cell clones of sis mRNA expression and colony formation in agar indicated that, above a threshold, a linear, positive correlation existed between sis overexpression and acquired anchorage independence. The sis-overexpressing cells formed transient, regressing tumor nodules when injected into nude mice, consistent with the finite life span which they retained. Protein products generated from the transfected c-sis construct in two overexpressing clones were immunoprecipitated with anti-human PDGF antibodies. One clone contained an apparent PDGF dimer of 21 kilodaltons; the second clone contained only on apparent PDGF monomer of 12 kilodaltons, which was shown to account for all of the mitogenic activity present in the cells, essentially all of which was concentrated in the membrane fraction. The results demonstrate a clear link between sis overexpression and acquisition of a partially transformed, anchorage-independent phenotype, and when combined with previous observations of sis overexpression in human tumors, clearly implicate sis overexpression as a genetic mechanism which contributes to human cell transformation.

  8. Immunosuppression during active tuberculosis is characterized by decreased interferon- gamma production and CD25 expression with elevated forkhead box P3, transforming growth factor- beta , and interleukin-4 mRNA levels.

    PubMed

    Roberts, Teri; Beyers, Nulda; Aguirre, Ana; Walzl, Gerhard

    2007-03-15

    The balance between effector and regulatory responses after Mycobacterium tuberculosis infection may dictate outcome and progression to active disease. We investigated effector and regulatory T cell responses in bacille Calmette-Guerin (BCG)-stimulated peripheral blood mononuclear cells and whole blood cultures from persons with active tuberculosis (TB), persons with TB at the end of 6 months of treatment, and healthy control subjects with latent TB infection. All 3 groups displayed BCG-induced increases in effector and regulatory T cell phenotypes as defined by CD4(+)CD25(lo) and CD4(+)CD25(hi) T cells, respectively. In case patients with active disease, BCG stimulation induced the lowest increase of CD25, CD4(+)CD25(hi), CTLA-4, and interferon- gamma . However, these case patients expressed the highest mRNA levels of forkhead box P3, transforming growth factor (TGF)- beta , and interleukin (IL)-4 and a lower T-bet : GATA-3 ratio. There were no significant differences in IL-4 delta 2, IL-10, or TGF- beta receptor-II mRNA expression between groups. Together, these results suggest that immunosuppression seen after mycobacterial stimulation in case patients with active TB is associated with naturally occurring regulatory T cells.

  9. Identification of the Thiol Isomerase-binding Peptide, Mastoparan, as a Novel Inhibitor of Shear-induced Transforming Growth Factor β1 (TGF-β1) Activation*

    PubMed Central

    Brophy, Teresa M.; Coller, Barry S.; Ahamed, Jasimuddin

    2013-01-01

    TGF-β1 is a disulfide-bonded homodimeric protein produced by platelets and other cells that plays a role in many physiologic and pathologic processes. TGF-β1 is secreted as an inactive large latent complex (LLC) comprised of TGF-β1, latency-associated peptide, and latent TGF-β binding protein 1. We previously demonstrated that shear force can activate LLC and that thiol-disulfide exchange contributes to the process. We have now investigated the role of thiol isomerases in the activation of LLC in platelet releasates (PR) and recombinant LLC. The wasp venom peptide mastoparan, which inhibits the chaperone activity of PDI, inhibited stirring- and shear-induced activation of latent TGF-β1 by 90 and 75% respectively. To identify the proteins that bind to mastoparan either directly or indirectly, PR were chromatographed on a mastoparan affinity column. Latent TGF-β binding protein 1, latency-associated peptide, TGF-β1, clusterin, von Willebrand factor, multimerin-1, protein disulfide isomerase (PDI), ERp5, ERp57, and ERp72 eluted specifically from the column. Anti-PDI RL90 attenuated the inhibitory effect of mastoparan on LLC activation. Furthermore, reduced PDI inhibited activation of PR LLC, whereas oxidized PDI had no effect. We conclude that thiol isomerases and thiol-disulfide exchange contribute to TGF-β1 activation and identify a number of molecules that may participate in the process. PMID:23463512

  10. Transforming Growth Factor-β and the Hallmarks of Cancer

    PubMed Central

    Tian, Maozhen; Neil, Jason R.; Schiemann, William P.

    2010-01-01

    Tumorigenesis is in many respects a process of dysregulated cellular evolution that drives malignant cells to acquire six phenotypic hallmarks of cancer, including their ability to proliferate and replicate autonomously, to resist cytostatic and apoptotic signals, and to induce tissue invasion, metastasis, and angiogenesis. Transforming growth factor-β (TGF-β) is a potent pleiotropic cytokine that functions as a formidable barrier to the development of cancer hallmarks in normal cells and tissues. Paradoxically, tumorigenesis counteracts the tumor suppressing activities of TGF-β, thus enabling TGF-β to stimulate cancer invasion and metastasis. Fundamental gaps exist in our knowledge of how malignant cells overcome the cytostatic actions of TGF-β, and of how TGF-β stimulates the acquisition of cancer hallmarks by developing and progressing human cancers. Here we review the molecular and cellular mechanisms that underlie the ability of TGF-β to mediate tumor suppression in normal cells, and conversely, to facilitate cancer progression and disease dissemination in malignant cells. PMID:20940046

  11. Transforming growth factor-β and the hallmarks of cancer.

    PubMed

    Tian, Maozhen; Neil, Jason R; Schiemann, William P

    2011-06-01

    Tumorigenesis is in many respects a process of dysregulated cellular evolution that drives malignant cells to acquire six phenotypic hallmarks of cancer, including their ability to proliferate and replicate autonomously, to resist cytostatic and apoptotic signals, and to induce tissue invasion, metastasis, and angiogenesis. Transforming growth factor-β (TGF-β) is a potent pleiotropic cytokine that functions as a formidable barrier to the development of cancer hallmarks in normal cells and tissues. Paradoxically, tumorigenesis counteracts the tumor suppressing activities of TGF-β, thus enabling TGF-β to stimulate cancer invasion and metastasis. Fundamental gaps exist in our knowledge of how malignant cells overcome the cytostatic actions of TGF-β, and of how TGF-β stimulates the acquisition of cancer hallmarks by developing and progressing human cancers. Here we review the molecular and cellular mechanisms that underlie the ability of TGF-β to mediate tumor suppression in normal cells, and conversely, to facilitate cancer progression and disease dissemination in malignant cells.

  12. Modifying muscular dystrophy through transforming growth factor-β.

    PubMed

    Ceco, Ermelinda; McNally, Elizabeth M

    2013-09-01

    Muscular dystrophy arises from ongoing muscle degeneration and insufficient regeneration. This imbalance leads to loss of muscle, with replacement by scar or fibrotic tissue, resulting in muscle weakness and, eventually, loss of muscle function. Human muscular dystrophy is characterized by a wide range of disease severity, even when the same genetic mutation is present. This variability implies that other factors, both genetic and environmental, modify the disease outcome. There has been an ongoing effort to define the genetic and molecular bases that influence muscular dystrophy onset and progression. Modifier genes for muscle disease have been identified through both candidate gene approaches and genome-wide surveys. Multiple lines of experimental evidence have now converged on the transforming growth factor-β (TGF-β) pathway as a modifier for muscular dystrophy. TGF-β signaling is upregulated in dystrophic muscle as a result of a destabilized plasma membrane and/or an altered extracellular matrix. Given the important biological role of the TGF-β pathway, and its role beyond muscle homeostasis, we review modifier genes that alter the TGF-β pathway and approaches to modulate TGF-β activity to ameliorate muscle disease.

  13. Mutant p53 disrupts role of ShcA protein in balancing Smad protein-dependent and -independent signaling activity of transforming growth factor-β (TGF-β).

    PubMed

    Lin, Shu; Yu, Lan; Yang, Junhua; Liu, Zhao; Karia, Bijal; Bishop, Alexander J R; Jackson, James; Lozano, Guillermina; Copland, John A; Mu, Xiaoxin; Sun, Beicheng; Sun, Lu-Zhe

    2011-12-23

    Biomarkers are lacking for identifying the switch of transforming growth factor-β (TGF-β) from tumor-suppressing to tumor-promoting. Mutated p53 (mp53) has been suggested to switch TGF-β to a tumor promoter. However, we found that mp53 does not always promote the oncogenic role of TGF-β. Here, we show that endogenous mp53 knockdown enhanced cell migration and phosphorylation of ERK in DU145 prostate cancer cells. Furthermore, ectopic expression of mp53 in p53-null PC-3 prostate cancer cells enhanced Smad-dependent signaling but inhibited TGF-β-induced cell migration by down-regulating activated ERK. Reactivation of ERK by the expression of its activator, MEK-1, restored TGF-β-induced cell migration. Because TGF-β is known to activate the MAPK/ERK pathway through direct phosphorylation of the adaptor protein ShcA and MAPK/ERK signaling is pivotal to tumor progression, we investigated whether ShcA contributed to mp53-induced ERK inhibition and the conversion of the role of TGF-β during carcinogenesis. We found that mp53 expression led to a decrease of phosphorylated p52ShcA/ERK levels and an increase of phosphorylated Smad levels in a panel of mp53-expressing cancer cell lines and in mammary glands and tumors from mp53 knock-in mice. By manipulating ShcA levels to regulate ERK and Smad signaling in human untransformed and cancer cell lines, we showed that the role of TGF-β in regulating anchorage-dependent and -independent growth and migration can be shifted between growth suppression and migration promotion. Thus, our results for the first time suggest that mp53 disrupts the role of ShcA in balancing the Smad-dependent and -independent signaling activity of TGF-β and that ShcA/ERK signaling is a major pathway regulating the tumor-promoting activity of TGF-β.

  14. Autocrine growth inhibition by transforming growth factor β-1 (TGFβ-1) in human neuroendocrine tumour cells

    PubMed Central

    Wimmel, A; Wiedenmann, B; Rosewicz, S

    2003-01-01

    Background and aim: The role of transforming growth factor β-1 (TGFβ-1) in neuroendocrine tumour biology is currently unknown. We therefore examined the expression and biological significance of TGFβ signalling components in neuroendocrine tumours (NETs) of the gastroenteropancreatic (GEP) tract. Methods: Expression of TGFβ-1 and its receptors, Smads and Smad regulated proteins, was examined in surgically resected NET specimens and human NET cell lines by immunohistochemistry, reverse transcriptase-polymerase chain reaction, immunoblotting, and ELISA. Activation of TGFβ-1 dependent promoters was tested by transactivation assays. Growth regulation was evaluated by cell numbers, soft agar assays, and cell cycle analysis using flow cytometry. The role of endogenous TGFβ was assessed by a TGFβ neutralising antibody and stable transfection of a dominant negative TGFβR II receptor construct. Results: Coexpression of TGFβ-1 and its receptors TGFβR I and TGFβR II was detected in 67% of human NETs and in all three NET cell lines examined. NET cell lines expressed the TGFβ signal transducers Smad 2, 3, and 4. In two of the three cell lines, TGFβ-1 treatment resulted in transactivation of a TGFβ responsive reporter construct as well as inhibition of c-myc and induction of p21(WAF1) expression. TGFβ-1 inhibited anchorage dependent and independent growth in a time and dose dependent manner in TGFβ-1 responsive cell lines. TGFβ-1 mediated growth inhibition was due to G1 arrest without evidence of induction of apoptosis. Functional inactivation of endogenous TGFβ revealed the existence of an autocrine antiproliferative loop in NET cells. Conclusions: Neuroendocrine tumour cells of the gastroenteropancreatic tract are subject to paracrine and autocrine growth inhibition by TGFβ-1, which may account in part for the low proliferative index of this tumour entity. PMID:12912863

  15. Linagliptin but not Sitagliptin inhibited transforming growth factor-β2-induced endothelial DPP-4 activity and the endothelial-mesenchymal transition.

    PubMed

    Shi, Sen; Kanasaki, Keizo; Koya, Daisuke

    2016-02-26

    Dipeptidyl peptidase (DPP)-4 plays an important role in endothelial cell biology. We have shown that the DPP-4 inhibitor Linagliptin can inhibit the endothelial-mesenchymal transition (EndMT) and ameliorate diabetic kidney fibrosis associated with the suppression of DPP-4 protein levels via the induction of miR-29. The current study demonstrated that such effects of Linagliptin on endothelial cell profibrotic programs were drug-specific but not class effects. In the cell-free system, both Linagliptin and Sitagliptin inhibited recombinant DPP-4 activity in a concentration-dependent manner. Linagliptin can inhibit all of the following: DPP-4 activity and protein level, integrin β1 protein levels, EndMT, and DPP-4 3'UTR activity; Sitagliptin, however, inhibited none of these in the current study. Additionally, TGF-β2 induced both the induction of VEGF-R1 and the suppression of VEGF-R2 levels in endothelial cells, and both were inhibited by Linagliptin but not by Sitagliptin. miR-29, the miR that negatively regulates the 3'UTR of DPP-4 mRNA, was suppressed by TGF-β2 and restored by Linagliptin but not by Sitagliptin. Following the overexpression of pCMV-DPP-4-GFP and pCMV6-Myc-DPP-4 in endothelial cells, the proximity of Myc-DPP-4 and DPP-4-GFP was suppressed by Linagliptin but not by Sitagliptin, suggesting that only Linagliptin inhibited the homo-dimer formation of DPP-4 in endothelial cells; this difference in activity between the two gliptins could explain their diverse effects on endothelial cell biology. In conclusion, each of the DPP-4 inhibitors may have unique drug-specific effects.

  16. Special phase transformation and crystal growth pathways observed in nanoparticles†

    PubMed Central

    Gilbert, Benjamin; Zhang, Hengzhong; Huang, Feng; Finnegan, Michael P; Waychunas, Glenn A; Banfield, Jillian F

    2003-01-01

    Phase transformation and crystal growth in nanoparticles may happen via mechanisms distinct from those in bulk materials. We combine experimental studies of as-synthesized and hydrothermally coarsened titania (TiO2) and zinc sulfide (ZnS) with thermodynamic analysis, kinetic modeling and molecular dynamics (MD) simulations. The samples were characterized by transmission electron microscopy, X-ray diffraction, synchrotron X-ray absorption and scattering, and UV-vis spectroscopy. At low temperatures, phase transformation in titania nanoparticles occurs predominantly via interface nucleation at particle–particle contacts. Coarsening and crystal growth of titania nanoparticles can be described using the Smoluchowski equation. Oriented attachment-based crystal growth was common in both hydrothermal solutions and under dry conditions. MD simulations predict large structural perturbations within very fine particles, and are consistent with experimental results showing that ligand binding and change in aggregation state can cause phase transformation without particle coarsening. Such phenomena affect surface reactivity, thus may have important roles in geochemical cycling.

  17. c-Jun N-terminal kinase 1 promotes transforming growth factor-β1-induced epithelial-to-mesenchymal transition via control of linker phosphorylation and transcriptional activity of Smad3.

    PubMed

    Velden, Jos L J van der; Alcorn, John F; Guala, Amy S; Badura, Elsbeth C H L; Janssen-Heininger, Yvonne M W

    2011-04-01

    Transforming growth factor (TGF)-β1 is a key mediator of lung remodeling and fibrosis. Epithelial cells are both a source of and can respond to TGF-β1 with epithelial-to-mesenchymal transition (EMT). We recently determined that TGF-β1-induced EMT in lung epithelial cells requires the presence of c-Jun N-terminal kinase (JNK) 1. Because TGF-β1 signals via Smad complexes, the goal of the present study was to determine the impact of JNK1 on phosphorylation of Smad3 and Smad3-dependent transcriptional responses in lung epithelial cells. Evaluation of JNK1-deficient lung epithelial cells demonstrated that TGF-β1-induced terminal phosphorylation of Smad3 was similar, whereas phosphorylation of mitogen-activated protein kinase sites in the linker regions of Smad3 was diminished, in JNK1-deficient cells compared with wild-type cells. In comparison to wild-type Smad3, expression of a mutant Smad3 in which linker mitogen-activated protein kinase sites were ablated caused a marked attenuation in JNK1 or TGF-β1-induced Smad-binding element transcriptional activity, and expression of plasminogen activator inhibitor-1, fibronectin-1, high-mobility group A2, CArG box-binding factor-A, and fibroblast-specific protein-1, genes critical in the process of EMT. JNK1 enhanced the interaction between Smad3 and Smad4, which depended on linker phosphorylation of Smad3. Conversely, Smad3 with phosphomimetic mutations in the linker domain further enhanced EMT-related genes and proteins, even in the absence of JNK1. Finally, we demonstrated a TGF-β1-induced interaction between Smad3 and JNK1. Collectively, these results demonstrate that Smad3 phosphorylation in the linker region and Smad transcriptional activity are directly or indirectly controlled by JNK1, and provide a putative mechanism whereby JNK1 promotes TGF-β1-induced EMT.

  18. Ginsenoside F2 reduces hair loss by controlling apoptosis through the sterol regulatory element-binding protein cleavage activating protein and transforming growth factor-β pathways in a dihydrotestosterone-induced mouse model.

    PubMed

    Shin, Heon-Sub; Park, Sang-Yong; Hwang, Eun-Son; Lee, Don-Gil; Mavlonov, Gafurjon Turdalievich; Yi, Tae-Hoo

    2014-01-01

    This study was conducted to test whether ginsenoside F2 can reduce hair loss by influencing sterol regulatory element-binding protein (SREBP) cleavage-activating protein (SCAP) and the transforming growth factor beta (TGF-β) pathway of apoptosis in dihydrotestosterone (DHT)-treated hair cells and in a DHT-induced hair loss model in mice. Results for ginsenoside F2 were compared with finasteride. DHT inhibits proliferation of hair cells and induces androgenetic alopecia and was shown to activate an apoptosis signal pathway both in vitro and in vivo. The cell-based 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that the proliferation rates of DHT-treated human hair dermal papilla cells (HHDPCs) and HaCaTs increased by 48% in the ginsenoside F2-treated group and by 12% in the finasteride-treated group. Western blot analysis showed that ginsenoside F2 decreased expression of TGF-β2 related factors involved in hair loss. The present study suggested a hair loss related pathway by changing SCAP related apoptosis pathway, which has been known to control cholesterol metabolism. SCAP, sterol regulatory element-binding protein (SREBP) and caspase-12 expression in the ginsenoside F2-treated group were decreased compared to the DHT and finasteride-treated group. C57BL/6 mice were also prepared by injection with DHT and then treated with ginsenoside F2 or finasteride. Hair growth rate, density, thickness measurements and tissue histotological analysis in these groups suggested that ginsenoside F2 suppressed hair cell apoptosis and premature entry to catagen more effectively than finasteride. Our results indicated that ginsenoside F2 decreased the expression of TGF-β2 and SCAP proteins, which have been suggested to be involved in apoptosis and entry into catagen. This study provides evidence those factors in the SCAP pathway could be targets for hair loss prevention drugs.

  19. Heparin-binding epidermal growth factor-like growth factor, a v-Jun target gene, induces oncogenic transformation

    PubMed Central

    Fu, Shu-ling; Bottoli, Ivan; Goller, Martin; Vogt, Peter K.

    1999-01-01

    Jun is a transcription factor belonging to the activator protein 1 family. A mutated version of Jun (v-Jun) transduced by the avian retrovirus ASV17 induces oncogenic transformation in avian cell cultures and sarcomas in young galliform birds. The oncogenicity of Jun probably results from transcriptional deregulation of v-Jun-responsive target genes. Here we describe the identification and characterization of a growth-related v-Jun target, a homolog of heparin-binding epidermal growth factor-like growth factor (HB-EGF). HB-EGF is strongly expressed in chicken embryo fibroblasts (CEF) transformed by v-Jun. HB-EGF expression is not detectable or is marginal in nontransformed CEF. Using a hormone-inducible Jun-estrogen receptor chimera, we found that HB-EGF expression is correlated with v-Jun activity. In this system, induction of v-Jun is followed within 1 hr by elevated levels of HB-EGF. In CEF infected with various Jun mutants, HB-EGF expression is correlated with the oncogenic potency of the mutant. Constitutive expression of HB-EGF conveys to CEF the ability to grow in soft agar and to form multilayered foci of transformed cells on a solid substrate. These observations suggest that HB-EGF is an effector of Jun-induced oncogenic transformation. PMID:10318950

  20. Effect of sulodexide on plasma transforming growth factor-beta1 in healthy volunteers.

    PubMed

    Borawski, Jacek; Dubowski, Miroslaw; Pawlak, Krystyna; Mysliwiec, Michal

    2010-02-01

    It is unknown whether the glycosaminoglycan drug sulodexide interferes with transforming growth factor-beta1--a member of heparin-binding family and a potent regulator of human biology and diseases. Hence, a 2-week pilot study was performed in 11 healthy men. Sulodexide was initially administered intravenously in a single dose, then--orally for 12 days and--again intravenously on study completion. Initial injection had no effect on activated form of the growth factor measured in plasma after 10 and 120 min; no change was also observed after 120 min from drug ingestion on day 7. On final intravenous administration, the growth factor levels increased by almost 60% after 10 min and remained elevated; the 120-min levels directly correlated with sulodexide dosage. Baseline cytokine levels decreased during the 2-week trial by more than 50%. In conclusion, transforming growth factor-beta1 release and likely downregulation of its expression may constitute novel pharmacological effects of sulodexide.

  1. [Transformation of neuronal activity in the cat lateral geniculate body].

    PubMed

    Silakov, V L

    1976-05-01

    The neuronal activity transformations were studied in the cat LGB under the action of nembutal, light stimulation, and micropolarization of geniculate cells. The transformation of single spike activity into bursts was found to reflect the inhibitory state of the neurons. Their excitation entailed a reverse transformation. Short feed-back connections functioning within the microsystems of LGB neurons are supposed to underlie the transformations.

  2. Transforming growth factor beta 1-responsive element: closely associated binding sites for USF and CCAAT-binding transcription factor-nuclear factor I in the type 1 plasminogen activator inhibitor gene.

    PubMed Central

    Riccio, A; Pedone, P V; Lund, L R; Olesen, T; Olsen, H S; Andreasen, P A

    1992-01-01

    Transforming growth factor beta (TGF-beta) is the name of a group of closely related polypeptides characterized by a multiplicity of effects, including regulation of extracellular proteolysis and turnover of the extracellular matrix. Its cellular mechanism of action is largely unknown. TGF-beta 1 is a strong and fast inducer of type 1 plasminogen activator inhibitor gene transcription. We have identified a TGF-beta 1-responsive element in the 5'-flanking region of the human type 1 plasminogen activator inhibitor gene and shown that it is functional both in its natural context and when fused to a heterologous nonresponsive promoter. Footprinting and gel retardation experiments showed that two different nuclear factors, present in extracts from both TGF-beta 1-treated and nontreated cells, bind to adjacent sequences contained in the responsive unit. A palindromic sequence binds a trans-acting factor(s) of the CCAAT-binding transcription factor-nuclear factor I family. A partially overlapping dyad symmetry interacts with a second protein that much evidence indicates to be USF. USF is a transactivator belonging to the basic helix-loop-helix family of transcription factors. Mutations which abolish the binding of either CCAAT-binding transcription factor-nuclear factor I or USF result in reduction of transcriptional activation upon exposure to TGF-beta 1, thus showing that both elements of the unit are necessary for the TGF-beta 1 response. We discuss the possible relationship of these findings to the complexity of the TGF-beta action. Images PMID:1549130

  3. Nanowire growth by an electron beam induced massive phase transformation

    SciTech Connect

    Sood, Shantanu; Kisslinger, Kim; Gouma, Perena

    2014-11-15

    Tungsten trioxide nanowires of a high aspect ratio have been synthesized in-situ in a TEM under an electron beam of current density 14A/cm² due to a massive polymorphic reaction. Sol-gel processed pseudocubic phase nanocrystals of tungsten trioxide were seen to rapidly transform to one dimensional monoclinic phase configurations, and this reaction was independent of the substrate on which the material was deposited. The mechanism of the self-catalyzed polymorphic transition and accompanying radical shape change is a typical characteristic of metastable to stable phase transformations in nanostructured polymorphic metal oxides. A heuristic model is used to confirm the metastable to stable growth mechanism. The findings are important to the control electron beam deposition of nanowires for functional applications starting from colloidal precursors.

  4. Nanowire growth by an electron beam induced massive phase transformation

    DOE PAGES

    Sood, Shantanu; Kisslinger, Kim; Gouma, Perena

    2014-11-15

    Tungsten trioxide nanowires of a high aspect ratio have been synthesized in-situ in a TEM under an electron beam of current density 14A/cm² due to a massive polymorphic reaction. Sol-gel processed pseudocubic phase nanocrystals of tungsten trioxide were seen to rapidly transform to one dimensional monoclinic phase configurations, and this reaction was independent of the substrate on which the material was deposited. The mechanism of the self-catalyzed polymorphic transition and accompanying radical shape change is a typical characteristic of metastable to stable phase transformations in nanostructured polymorphic metal oxides. A heuristic model is used to confirm the metastable to stablemore » growth mechanism. The findings are important to the control electron beam deposition of nanowires for functional applications starting from colloidal precursors.« less

  5. Activation of Epidermal Growth Factor Receptor/p38/Hypoxia-inducible Factor-1α Is Pivotal for Angiogenesis and Tumorigenesis of Malignantly Transformed Cells Induced by Hexavalent Chromium.

    PubMed

    Kim, Donghern; Dai, Jin; Park, Youn-Hee; Fai, Leonard Yenwong; Wang, Lei; Pratheeshkumar, Poyil; Son, Young-Ok; Kondo, Kazuya; Xu, Mei; Luo, Jia; Shi, Xianglin; Zhang, Zhuo

    2016-07-29

    Hexavalent chromium (Cr(VI))-containing compounds are well established environmental carcinogens. Most mechanistic investigations of Cr(VI)-induced carcinogenesis focus on oxidative stress and various cellular responses, leading to malignant cell transformation or the first stage of metal-induced carcinogenesis. The development of malignantly transformed cells into tumors that require angiogenesis is the second stage. This study focuses on the second stage, in particular, the role of EGF receptor (EGFR) signaling in angiogenesis and tumorigenesis of Cr(VI)-transformed cells. Our preliminary studies have shown that EGFR is constitutively activated in Cr(VI)-transformed cells, in lung tissue from Cr(VI)-exposed animals, and in lung tumor tissue from a non-smoking worker occupationally exposed to Cr(VI) for 19 years. Using in vitro and in vivo models, the present study has investigated the role of EGFR in angiogenesis of Cr(VI)-transformed cells. The results show that Cr(VI)-transformed cells are angiogenic. Hypoxia-inducible factor-1α, pro-angiogenic protein matrix metalloproteinase 1, and VEGF are all highly expressed in Cr(VI)-transformed cells, in lung tissue from animals exposed to Cr(VI), and in lung tumor tissue from a non-smoking worker occupationally exposed to Cr(VI) for 19 years. p38 MAPK is also activated in Cr(VI)-transformed cells and in human lung tumor tissue. Inhibition of EGFR reduces p38 MAPK, resulting in decreased expression of hypoxia-inducible factor-1α, metalloproteinase 1, and VEGF, leading to suppressions of angiogenesis and tumorigenesis. Overall, the present study has demonstrated that EGFR plays an important role in angiogenesis and tumorigenesis of Cr(VI)-transformed cells.

  6. Epithelial-mesenchymal interactions and lung branching morphogenesis. Role of polyamines and transforming growth factor beta1.

    PubMed

    Stabellini, G; Locci, P; Calvitti, M; Evangelisti, R; Marinucci, L; Bodo, M; Caruso, A; Canaider, S; Carinci, P

    2001-01-01

    Lung branching morphogenesis is a result of epithelial-mesenchymal interactions, which are in turn dependent on extracellular matrix composition and cytokine regulation. Polyamines have recently been demonstrated as able to modify chick embryo skin differentiation. In this work we have examined the effects of putrescine and spermidine during chick embryo lung morphogenesis in organotypic cultures by morphological, histochemical and biochemical examination. To verify the role of polyamines, we used specific inhibitors, such as bis-cyclohexylammonium sulphate and alfa-difluoromethylornithine, and transforming growth factor beta1, an ornithine decarboxylase and polyamine stimulator. Our data show that lung morphogenesis is significantly altered following the induced mesenchymal glycosaminoglycan changes. The increase of mesenchymal glycosaminoglycans is correlated with a stimulation of lung development in the presence of polyamines, and with its inhibition when transforming growth factor beta1 is added to the culture medium. The morphometric data show a uniform increase of both the mesenchyme and epithelial branching with spermidine and putrescine stimulus, whereas the mesenchymal substance alone is significantly increased in apical-median lung sections with transforming growth factor beta1 and transforming growth factor beta1 + spermidine lung cultures. Transforming growth factor beta1 and transforming growth factor beta1 + spermidine confirm the blocking of epithelial branching formations and fibroblast activation, and show that polyamines are unable to prevent the blocking of epithelial cells due to the inhibitory effect of transforming growth factor beta1.

  7. Transforming growth factor-β1 induces type II collagen and aggrecan expression via activation of extracellular signal-regulated kinase 1/2 and Smad2/3 signaling pathways.

    PubMed

    Zhu, Yanhui; Tao, Hairong; Jin, Chen; Liu, Yonzhang; Lu, Xiongwei; Hu, Xiaopeng; Wang, Xiang

    2015-10-01

    Transforming growth factor (TGF)‑β regulates the anabolic metabolism of articular cartilage and prevents cartilage degradation. TGF‑β1 influences cellular proliferation, differentiation and the extracellular matrix through activation of the extracellular signal‑regulated kinase (ERK)1/2 and Smad2/3 signaling pathways. However, it has remained to be fully elucidated precisely how the ERK1/2 and Smad2/3 signaling pathways mediate anabolic processes of articular cartilage. The present study investigated how ERK1/2 and Smad2/3 signaling mediate TGF‑β1‑stimulated type II collagen and aggrecan expression in rat chondrocytes. The results confirmed that TGF‑β1 stimulates type II collagen and aggrecan expression in rat chondrocytes, and furthermore, that the ERK1/2 and Smad2/3 signaling pathways were activated by TGF‑β1. Conversely, the TGF‑β receptor I (ALK5) kinase inhibitor SB525334 significantly impaired TGF‑β1‑induced type II collagen and aggrecan expression, coinciding with a reduction of ERK1/2 and Smad3 phosphorylation. In addition, TGF‑β1‑induced type II collagen and aggrecan expression were significantly suppressed by ERK1/2 inhibitor PD98059. Similarly, TGF‑β1‑stimulated type II collagen and aggrecan expression were decreased in the presence of a Smad3 phosphorylation inhibitor SIS3. Therefore, the present study demonstrated that the ERK1/2 and Smad2/3 signaling pathways regulate type II collagen and aggrecan expression in rat chondrocytes.

  8. Transforming growth factor (TGF)-. alpha. in human milk

    SciTech Connect

    Okada, Masaki; Wakai, Kae; Shizume, Kazuo ); Iwashita, Mitsutoshi ); Ohmura, Eiji; Kamiya, Yoshinobu; Murakami, Hitomi; Onoda, Noritaka; Tsushima, Toshio

    1991-01-01

    Transforming growth factor (TGF)-{alpha} and epidermal growth factor (EGF) were measured in human milk by means of homologous radioimmunoassay. As previously reported, EGF concentration in the colostrum was approximately 200 ng/ml and decreased to 50 ng/ml by day 7 postpartum. The value of immunoreactive (IR)-TGF-{alpha} was 2.2-7.2 ng/ml, much lower than that of EGF. In contrast to EGF, the concentration of IR-TGF-{alpha} was fairly stable during the 7 postpartum days. There was no relationship between the concentrations of IR-TGF-{alpha} and IR-EGF, suggesting that the regulatory mechanism in the release of the two growth factors is different. On gel-chromatography using a Sephadex G-50 column, IR-EGF appeared in the fraction corresponding to that of authentic human EGF, while 70%-80% of the IR-TGF-{alpha} was eluted as a species with a molecular weight greater than that of authentic human TGF-{alpha}. Although the physiological role of TGF-{alpha} in milk is not known, it is possible that it is involved in the development of the mammary gland and/or the growth of newborn infants.

  9. Incisional wound healing in transforming growth factor-beta1 null mice.

    PubMed

    Koch, R M; Roche, N S; Parks, W T; Ashcroft, G S; Letterio, J J; Roberts, A B

    2000-01-01

    Expression of endogenous transforming growth factor-beta1 is reduced in many animal models of impaired wound healing, and addition of exogenous transforming growth factor-beta has been shown to improve healing. To test the hypothesis that endogenous transforming growth factor-beta1 is essential for normal wound repair, we have studied wound healing in mice in which the transforming growth factor-beta1 gene has been deleted by homologous recombination. No perceptible differences were observed in wounds made in 3-10-day-old neonatal transforming growth factor-beta1 null mice compared to wild-type littermates. To preclude interference from maternally transferred transforming growth factor-beta1, cutaneous wounds were also made on the backs of 30-day-old transforming growth factor-beta1 null and littermate control mice treated with rapamycin, which extends their lifetime and suppresses the inflammatory response characteristic of the transforming growth factor-beta1 null mice. Again, no impairment in healing was seen in transforming growth factor-beta1 null mice. Instead these wounds showed an overall reduction in the amount of granulation tissue and an increased rate of epithelialization compared to littermate controls. Our data suggest that release of transforming growth factor-beta1 from degranulating platelets or secretion by infiltrating macrophages and fibroblasts is not critical to initiation or progression of tissue repair and that endogenous transforming growth factor-beta1 may actually function to increase inflammation and retard wound closure.

  10. [Activated Sludge Bacteria Transforming Cyanopyridines and Amides of Pyridinecarboxylic Acids].

    PubMed

    Demakov, V A; Vasil'ev, D M; Maksimova, Yu G; Pavlova, Yu A; Ovechkina, G V; Maksimov, A Yu

    2015-01-01

    Species diversity of bacteria from the activated sludge of Perm biological waste treatment facilities capable of transformation of cyanopyridines and amides of pyridinecarboxylic acids was investigated. Enrichment cultures in mineral media with 3-cyanopyridine as the sole carbon and nitrogen source were used to obtain 32 clones of gram-negative heterotrophic bacteria exhibiting moderate growth on solid and liquid media with 3- and 4-cyanopyridine. Sequencing of the 16S rRNA gene fragments revealed that the clones with homology of at least 99% belonged to the genera Acinetobacte, Alcaligenes, Delftia, Ochrobactrum, Pseudomonas, Stenotrophomonas, and Xanthobacter. PCR analysis showed that 13 out of 32 isolates contained the sequences (-1070 bp) homologous to the nitrilase genes reported previously in Alcaligenes faecalis JM3 (GenBank, D13419.1). Nine clones were capable of nitrile and amide transformation in minimal salt medium. Acinetobacter sp. 11 h and Alcaligenes sp. osv transformed 3-cyanopyridine to nicotinamide, while most of the clones possessed amidase activity (0.5 to 46.3 mmol/(g h) for acetamide and 0.1 to 5.6 mmol/(g h) for nicotinamide). Nicotinamide utilization by strain A. faecalis 2 was shown to result in excretion of a secondary metabolite, which was identified as dodecyl acrylate at 91% probability.

  11. Chondrocytes Directly Transform into Bone Cells in Mandibular Condyle Growth

    PubMed Central

    Jing, Y.; Zhou, X.; Han, X.; Jing, J.; von der Mark, K.; Wang, J.; de Crombrugghe, B.; Hinton, R.J.; Feng, J.Q.

    2015-01-01

    For decades, it has been widely accepted that hypertrophic chondrocytes undergo apoptosis prior to endochondral bone formation. However, very recent studies in long bone suggest that chondrocytes can directly transform into bone cells. Our initial in vivo characterization of condylar hypertrophic chondrocytes revealed modest numbers of apoptotic cells but high levels of antiapoptotic Bcl-2 expression, some dividing cells, and clear alkaline phosphatase activity (early bone marker). Ex vivo culture of newborn condylar cartilage on a chick chorioallantoic membrane showed that after 5 d the cells on the periphery of the explants had begun to express Col1 (bone marker). The cartilage-specific cell lineage–tracing approach in triple mice containing Rosa 26tdTomato (tracing marker), 2.3 Col1GFP (bone cell marker), and aggrecan CreERT2 (onetime tamoxifen induced) or Col10-Cre (activated from E14.5 throughout adult stage) demonstrated the direct transformation of chondrocytes into bone cells in vivo. This transformation was initiated at the inferior portion of the condylar cartilage, in contrast to the initial ossification site in long bone, which is in the center. Quantitative data from the Col10-Cre compound mice showed that hypertrophic chondrocytes contributed to ~80% of bone cells in subchondral bone, ~70% in a somewhat more inferior region, and ~40% in the most inferior part of the condylar neck (n = 4, P < 0.01 for differences among regions). This multipronged approach clearly demonstrates that a majority of chondrocytes in the fibrocartilaginous condylar cartilage, similar to hyaline cartilage in long bones, directly transform into bone cells during endochondral bone formation. Moreover, ossification is initiated from the inferior portion of mandibular condylar cartilage with expansion in one direction. PMID:26341973

  12. Insights into the Transforming Growth Factor-β Signaling Pathway in Cutaneous Melanoma

    PubMed Central

    Perrot, Carole Yolande; Javelaud, Delphine

    2013-01-01

    Transforming growth factor-β (TGF-β) is a pleiotropic growth factor with broad tissue distribution that plays critical roles during embryonic development, normal tissue homeostasis, and cancer. While its cytostatic activity on normal epithelial cells initially defined TGF-β signaling as a tumor suppressor pathway, there is ample evidence indicating that TGF-β is a potent pro-tumorigenic agent, acting via autocrine and paracrine mechanisms to promote peri-tumoral angiogenesis, together with tumor cell migration, immune escape, and dissemination to metastatic sites. This review summarizes the current knowledge on the implication of TGF-β signaling in melanoma. PMID:23717002

  13. Atomic mechanisms of diffusional nucleation and growth and comparisons with their counterparts in shear transformations

    NASA Astrophysics Data System (ADS)

    Aaronson, Hubert I.

    1993-02-01

    An integrated overview is presented of a viewpoint on the present understanding of nucleation and growth mechanisms in both diffusional and shear (martensitic) transformations. Special emphasis is placed on the roles played by the anisotropy of interphase boundary structure and energy and also upon elastic shear strain energy in both types of transformation. Even though diffusional nucleation is based on random statistical fluctuations, use of the time reversal principle shows that interfacial energy anisotropy leads to accurately reproducible orientation relationships and hence to partially or fully coherent boundaries, even when nucleation at a grain boundary requires an irrational orientation relationship to obtain. Since the fully coherent boundary areas separating most linear misfit compensating defects are wholly immobile during diffusional growth because of the improbability of moving substitutional atoms even temporarily into interstitial sites under conditions normally encountered, partially and fully coherent interphase boundaries should be immovable without the intervention of growth ledges. These ledges, however, must be heavily kinked and usually irregular in both spacing and path if they, too, are not to be similarly trapped. On the other hand, the large shear strain energy usually associated with martensite requires that its formation be initiated through a process which avoids the activation barrier associated with nucleation, perhaps by the Olson-Cohen matrix dislocation rearrangement mechanism. During growth, certain ledges on martensite plates serve as transformation dislocations and perform the crystal structure change (Bain strain). However, the terraces between these ledges in martensite (unlike those present during diffusional growth) are also mobile during non-fcc/hcp transformations; glissile dislocations on these terraces perform the lattice invariant deformation. Growth ledges operative during both diffusional and shear growth probably

  14. Inhibition of Nb2 T-lymphoma cell growth by transforming growth factor-beta.

    PubMed Central

    Rayhel, E J; Prentice, D A; Tabor, P S; Flurkey, W H; Geib, R W; Laherty, R F; Schnitzer, S B; Chen, R; Hughes, J P

    1988-01-01

    Transforming growth factor-beta (TGF-beta) inhibits proliferation of Nb2 cells, a rat T lymphoma, in response to lactogens and interleukin-2. Prostaglandins may play an important role in the pathway through which TGF-beta exerts its inhibitory actions, because prostaglandin E2 also inhibits proliferation of Nb2 cells, and indomethacin, an inhibitor of prostaglandin synthesis, reverses the inhibitory effects of TGF-beta on Nb2 cell proliferation. PMID:3262338

  15. [THE ROLE OF TRANSFORMING GROWTH FACTOR-B IN IMMUNOPATHOGENESIS OF DISEASES OF CONNECTIVE TISSUE].

    PubMed

    Rudoi, A S; Moskalev, A V; Sboitchakov, V B

    2016-02-01

    The recent studies of molecular physiology of fibrillin and pathophysiology of inherent disorders of structure and function of connective tissue such as dissection and aneurysm of aorta, myxomatously altered cusps and prolapses of mitral valve, syndrome of hyper-mobility of joints, demonstrated that important role in development of these malformations play alterations of transfer of signals by growth factors and matrix cellular interaction. These conditions under manifesting Marfan's syndrome can be a consequence of anomalies of fibrillin-1 which deficiency unbrakes process of activation of transforming growth factor-β (TGFβ). The involvement of TGFβ in pathogenesis of Marfan's syndrome permits consider antagonists of angiotensin-transforming enzymes as potential pharmaceuticals in therapy of this disease. The article presents analysis of publications' data related to this problem.

  16. Transforming growth factor beta 1, a cytokine with regenerative functions

    PubMed Central

    Sulaiman, Wale; Nguyen, Doan H.

    2016-01-01

    We review the biology and role of transforming growth factor beta 1 (TGF-β1) in peripheral nerve injury and regeneration, as it relates to injuries to large nerve trunks (i.e., sciatic nerve, brachial plexus), which often leads to suboptimal functional recovery. Experimental studies have suggested that the reason for the lack of functional recovery resides in the lack of sufficient mature axons reaching their targets, which is a result of the loss of the growth-supportive environment provided by the Schwann cells in the distal stump of injured nerves. Using an established chronic nerve injury and delayed repair animal model that accurately mimics chronic nerve injuries in humans, we summarize our key findings as well as others to better understand the pathophysiology of poor functional recovery. We demonstrated that 6 month TGF-β1 treatment for chronic nerve injury significantly improved Schwann cell capacity to support axonal regeneration. When combined with forskolin, the effect was additive, as evidenced by a near doubling of regenerated axons proximal to the repair site. We showed that in vivo application of TGF-β1 and forskolin directly onto chronically injured nerves reactivated chronically denervated Schwann cells, induced their proliferation, and upregulated the expression of regeneration-associated proteins. The effect of TGF-β1 and forskolin on old nerve injuries is quite impressive and the treatment regiment appears to mediate a growth-supportive milieu in the injured peripheral nerves. In summary, TGF-β1 and forskolin treatment reactivates chronically denervated Schwann cells and could potentially be used to extend and prolong the regenerative responses to promote axonal regeneration. PMID:27904475

  17. Notch activation drives adipocyte dedifferentiation and tumorigenic transformation in mice

    PubMed Central

    Yue, Feng; Karki, Anju; Castro, Beatriz; Wirbisky, Sara E.; Bidwell, Christopher A.; Freeman, Jennifer L.

    2016-01-01

    Liposarcomas (LPSs) are the most common soft-tissue cancer. Because of the lack of animal models, the cellular origin and molecular regulation of LPS remain unclear. Here, we report that mice with adipocyte-specific activation of Notch signaling (Ad/N1ICD) develop LPS with complete penetrance. Lineage tracing confirms the adipocyte origin of Ad/N1ICD LPS. The Ad/N1ICD LPS resembles human dedifferentiated LPS in histological appearance, anatomical localization, and gene expression signature. Before transformation, Ad/N1ICD adipocytes undergo dedifferentiation that leads to lipodystrophy and metabolic dysfunction. Although concomitant Pten deletion normalizes the glucose metabolism of Ad/N1ICD mice, it dramatically accelerates the LPS prognosis and malignancy. Transcriptomes and lipidomics analyses indicate that Notch activation suppresses lipid metabolism pathways that supply ligands to Pparγ, the master regulator of adipocyte homeostasis. Accordingly, synthetic Pparγ ligand supplementation induces redifferentiation of Ad/N1ICD adipocytes and tumor cells, and prevents LPS development in Ad/N1ICD mice. Importantly, the Notch target HES1 is abundantly expressed in human LPS, and Notch inhibition suppresses the growth of human dedifferentiated LPS xenografts. Collectively, ectopic Notch activation is sufficient to induce dedifferentiation and tumorigenic transformation of mature adipocytes in mouse. PMID:27573812

  18. Transformation of diclofenac in hybrid biofilm-activated sludge processes.

    PubMed

    Jewell, Kevin S; Falås, Per; Wick, Arne; Joss, Adriano; Ternes, Thomas A

    2016-11-15

    The biotransformation of diclofenac during wastewater treatment was investigated. Attached growth biomass from a carrier-filled compartment of a hybrid-MBBR at the wastewater treatment plant (WWTP) in Bad Ragaz, Switzerland was used to test the biotransformation. Laboratory-scale incubation experiments were performed with diclofenac and carriers and high-resolution LC-QTof-MS was implemented to monitor the biotransformation. Up to 20 diclofenac transformation products (TPs) were detected. Tentative structures were proposed for 16 of the TPs after characterization by MS(2) fragmentation and/or inferring the structure from the transformation pathway and the molecular formula given by the high resolution ionic mass. The remaining four TPs were unambiguously identified via analytical reference standards. The postulated reactions forming the TPs were: hydroxylation, decarboxylation, oxidation, amide formation, ring-opening and reductive dechlorination. Incubation experiments of individual TPs, those which were available as reference standards, provided a deeper look into the transformation pathways. It was found that the transformation consists of four main pathways but no pathway accounted for a clear majority of the transformation. A 10-day monitoring campaign of the full-scale plant confirmed an 88% removal of diclofenac (from approximately 1.6 μg/L in WWTP influent) and the formation of TPs as found in the laboratory was observed. One of the TPs, N-(2,6-dichlorophenyl)-2-indolinone detected at concentrations of around 0.25 μg/L in WWTP effluent, accounting for 16% of the influent diclofenac concentration. The biotransformation of carriers was compared to a second WWTP not utilising carriers. It was found that in contact with activated sludge, similar hydroxylation and decarboxylation reactions occurred but at much slower rates, whereas some reactions, e.g. reductive dechlorination, were not detected at all. Finally, incubation experiments were performed with

  19. Inhibitory effect of deferoxamine or macrophage activation on transformation of Paracoccidioides brasiliensis conidia ingested by macrophages: reversal by holotransferrin.

    PubMed

    Cano, L E; Gomez, B; Brummer, E; Restrepo, A; Stevens, D A

    1994-04-01

    Conidia of P. brasiliensis ingested by murine macrophages at 37 degrees C showed enhanced transformation to yeast cells and further intracellular growth compared with conidia in culture medium alone. Treatment of macrophages with the iron chelator deferoxamine inhibited the intracellular conidium-to-yeast transformation. Cytokine-activated macrophages could also exert this inhibitory effect. Holotransferrin reversed the inhibitory effect of either deferoxamine or activated macrophages on intracellular conidium-to-yeast transformation. These results indicate that iron restriction is one of the mechanisms by which activated macrophages control the intracellular transformation of ingested conidia and growth of yeast cells.

  20. Inhibitory effect of deferoxamine or macrophage activation on transformation of Paracoccidioides brasiliensis conidia ingested by macrophages: reversal by holotransferrin.

    PubMed Central

    Cano, L E; Gomez, B; Brummer, E; Restrepo, A; Stevens, D A

    1994-01-01

    Conidia of P. brasiliensis ingested by murine macrophages at 37 degrees C showed enhanced transformation to yeast cells and further intracellular growth compared with conidia in culture medium alone. Treatment of macrophages with the iron chelator deferoxamine inhibited the intracellular conidium-to-yeast transformation. Cytokine-activated macrophages could also exert this inhibitory effect. Holotransferrin reversed the inhibitory effect of either deferoxamine or activated macrophages on intracellular conidium-to-yeast transformation. These results indicate that iron restriction is one of the mechanisms by which activated macrophages control the intracellular transformation of ingested conidia and growth of yeast cells. PMID:8132359

  1. Transforming growth factor-beta and wound healing.

    PubMed

    Faler, Byron J; Macsata, Robyn A; Plummer, Dahlia; Mishra, Lopa; Sidawy, Anton N

    2006-03-01

    Acute and chronic wounds are a source of significant morbidity for patients, and they demand a growing portion of health-care time and finances to be devoted to their care. Transforming growth factor-beta (TGF-beta) has surfaced from abundant research as a key signal in orchestrating wound repair. In beginning this review, we discuss the inflammatory, proliferative, and maturational phases of wound healing. We then focus on TGF-beta by first discussing the pathway from its production to the target cell where Smad proteins execute an intracellular signaling cascade. To review TGF-beta's role in wound healing, we discuss the actions of it individually on keratinocytes, fibroblasts, endothelial cells, and monocytes, which are the major cell types involved in wound repair. From illustrating these cellular actions of TGF-beta, we summarize its multipotent role in the process of wound repair. As a clinical correlation, we also review research dedicated to the involvement of TGF-beta in venous stasis ulcers.

  2. Impact of epidermal growth factor receptor and transforming growth factor-α on hepatitis C virus-induced hepatocarcinogenesis.

    PubMed

    Badawy, Afkar Abdel-Ghany; El-Hindawi, Ali; Hammam, Olfat; Moussa, Mona; Gabal, Samia; Said, Noha

    2015-10-01

    Epidermal growth factor receptor system plays a central hepato-protective and pro-regenerative role in liver. Transforming growth factor-α (TGF-α) is an important autocrine growth regulator of hepatocytes that plays a role in development of hepatocellular carcinoma (HCC) among patients with chronic hepatitis C (CHC). This study was done on 40 core liver biopsies from patients with CHC, 20 liver specimens from HCC cases on top of CHC as well as five normal controls. All were immunohistochemically stained with epidermal growth factor receptor (EGFR) and TGF-α antibodies. Some selected HCC cases were submitted for FISH technique to detect EGFR gene alteration. By immunohistochemistry EGFR and TGF-α were overexpressed in HCC and cirrhotic cases compared to CHC cases without cirrhosis. Also, their expression was stronger in CHC cases with higher grades of activity and stages of fibrosis compared to lower ones. FISH positive results for EGFR were detected in 33.3% of the examined HCC cases. EGFR and TGF-α can be used as predictive markers for activity, fibrosis, and carcinogenesis in CHC patients. Overexpression of EGFR in HCC patients can be promising in selecting those who can get benefit from anti-EGFR target therapy.

  3. Effect of transforming growth factor-alpha on inositol phospholipid metabolism in human epidermoid carcinoma cells

    SciTech Connect

    Kato, M.; Takenawa, T.; Twardzik, D.R.

    1988-08-01

    Transforming growth factor-alpha (TGF-alpha) stimulates (in a dose-dependent manner) the incorporation of (/sup 32/P)Pi into phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PIP), phosphatidylinositol 4,5-bisphosphate (PIP2), and phosphatidic acid (PA) in the human epidermoid carcinoma cell line (A431). The effect of TGF-alpha on the incorporation was found to be similar to that of EGF. On the other hand, a striking difference in the activation of diacylglycerol (DG) kinase activity was seen between TGF-alpha and EGF. At least 100 times more TGF-alpha was required to achieve maximal stimulation of DG kinase activity relative to EGF. These results suggest that the activation of DG kinase by TGF-alpha may involve a mechanism independent from or subsequent to activation of the EGF receptor.

  4. Transforming growth factor alpha and epidermal growth factor levels in normal human gastrointestinal mucosa.

    PubMed Central

    Cartlidge, S. A.; Elder, J. B.

    1989-01-01

    Acid soluble proteins from 23 samples of normal human gastrointestinal mucosa derived from four normal adult organ donors were extracted and subjected to specific radiommunoassays for transforming growth factor alpha (TGF alpha) and urogastrone epidermal growth factor (URO-EGF). All tissues were found to contain immunoreactive TGF alpha and levels ranged from 57 to 4,776 pg-1 wet weight of tissue. Although levels varied between tissue donors, the distribution of TGF alpha throughout the gastrointestinal tract appeared similar in all cases. URO-EGF levels were much lower (0-216 pg g-1 wet weight). TGF alpha levels in extracts of gastrointestinal mucosa from a 7-year-old female donor were higher and the observed distribution was markedly different from adult levels. URO-EGF was not detected in mucosal or submucosal tissue extracts from this patient. Further studies in juveniles are indicated. PMID:2803941

  5. Aqueous Date Flesh or Pits Extract Attenuates Liver Fibrosis via Suppression of Hepatic Stellate Cell Activation and Reduction of Inflammatory Cytokines, Transforming Growth Factor-β1 and Angiogenic Markers in Carbon Tetrachloride-Intoxicated Rats

    PubMed Central

    Al-Rasheed, Nouf M.; Attia, Hala A.; Mohamad, Raeesa A.; Al-Rasheed, Nawal M.; Al-Amin, Maha A.; AL-Onazi, Asma

    2015-01-01

    Previous data indicated the protective effect of date fruit extract on oxidative damage in rat liver. However, the hepatoprotective effects via other mechanisms have not been investigated. This study was performed to evaluate the antifibrotic effect of date flesh extract (DFE) or date pits extract (DPE) via inactivation of hepatic stellate cells (HSCs), reducing the levels of inflammatory, fibrotic and angiogenic markers. Coffee was used as reference hepatoprotective agent. Liver fibrosis was induced by injection of CCl4 (0.4 mL/kg) three times weekly for 8 weeks. DFE, DPE (6 mL/kg), coffee (300 mg/kg), and combination of coffee + DFE and coffee + DPE were given to CCl4-intoxicated rats daily for 8 weeks. DFE, DPE, and their combination with coffee attenuated the elevated levels of inflammatory cytokines including tumor necrosis factor-α, interleukin-6, and interleukin-1β. The increased levels of transforming growth factor-β1 and collagen deposition in injured liver were alleviated by both extracts. CCl4-induced expression of α-smooth muscle actin was suppressed indicating HSCs inactivation. Increased angiogenesis was ameliorated as revealed by reduced levels and expression of vascular endothelial growth factor and CD31. We concluded that DFE or DPE could protect liver via different mechanisms. The combination of coffee with DFE or DPE may enhance its antifibrotic effects. PMID:25945106

  6. Efficient synthesis of human type alpha transforming growth factor: its physical and biological characterization.

    PubMed Central

    Tam, J P; Sheikh, M A; Solomon, D S; Ossowski, L

    1986-01-01

    Human transforming growth factor type alpha (TGF-alpha) was synthesized by a stepwise solid-phase method with an overall yield of 26%. Synthetic TGF-alpha, consisting of 50 amino acid residues deduced from a cDNA precursor sequence, was purified in a single HPLC step. The homogeneity and primary structure were confirmed by several criteria including Edman degradation and mass spectrometry. Synthetic TGF-alpha was as active as murine epidermal growth factor in binding to the epidermal growth factor receptor and in stimulation of anchorage-dependent and of anchorage-independent growth of normal indicator cells in culture. Synthetic TGF-alpha stimulated plasminogen activator production in A 431 and HeLa cells; the stimulation was similar to that induced by epidermal growth factor. Furthermore, synthetic human TGF-alpha showed similar immunoreactivity when compared with rat TGF-alpha. Thus, the 50-amino acid TGF-alpha is likely to be the bioactive principle produced and secreted by tumor cell lines. PMID:3490662

  7. Phosphorylation of Dok1 by Abl family kinases inhibits CrkI transforming activity

    PubMed Central

    Ng, Khong Y.; Yin, Taofei; Machida, Kazuya; Wu, Yi I.; Mayer, Bruce J.

    2014-01-01

    The Crk SH2/SH3 adaptor and the Abl nonreceptor tyrosine kinase were first identified as oncoproteins, and both can induce tumorigenesis when overexpressed or mutationally activated. We previously reported the surprising finding that inhibition or knockdown of Abl family kinases enhanced transformation of mouse fibroblasts by CrkI. Abl family inhibitors are currently used or are being tested for treatment of human malignancies, and our finding raised concerns that such inhibitors might actually promote the growth of tumors overexpressing CrkI. Here, we identify the Dok1 adaptor as the key effector for the enhancement of CrkI transformation by Abl inhibition. We show that phosphorylation of tyrosines 295 and 361 of Dok1 by Abl family kinases suppresses CrkI transforming activity, and that upon phosphorylation these tyrosines bind the SH2 domains of the Ras inhibitor p120 RasGAP. Knockdown of RasGAP resulted in a similar enhancement of CrkI transformation, consistent with a critical role for Ras activity. Imaging studies using a FRET sensor of Ras activation revealed alterations in the localization of activated Ras in CrkI-transformed cells. Our results support a model in which Dok1 phosphorylation normally suppresses localized Ras pathway activity in Crk-transformed cells via recruitment and/or activation of RasGAP, and that preventing this negative feedback mechanism by inhibiting Abl family kinases leads to enhanced transformation by Crk. PMID:25043303

  8. Thermally activated martensitic transformations in Mg-PSZ

    SciTech Connect

    Behrens, G.; Heuer, A.H.

    1996-04-01

    The thermally activated, stress-assisted martensitic tetragonal {yields} monoclinic (t {yields} m) and tetragonal {yields} orthorhombic (t {yields} o) transformations in a high-toughness Mg-PSZ were investigated by monitoring the phase assemblage with Raman spectroscopy after a variety of heat treatments and loading conditions. After a short anneal at 1,000 C, which transforms m- and o-ZrO{sub 2} to the t polymorph, isothermal t {yields} m and t {yields} o transformations occur at room temperature during the months following the anneal. The transformation rates in the annealed samples are greatly enhanced under external stress. Alternatively, samples containing regions of significant residual stress, introduced by indentation for example, and then annealed at relatively low temperatures, underwent additional thermally activated transformation in the stressed regions. The thermodynamics and kinetics of this complex transformation ``plasticity,`` and its effect on mechanical properties, are discussed.

  9. K-Ras promotes growth transformation and invasion of immortalized human pancreatic cells by Raf and phosphatidylinositol 3-kinase signaling.

    PubMed

    Campbell, Paul M; Groehler, Angela L; Lee, Kwang M; Ouellette, Michel M; Khazak, Vladimir; Der, Channing J

    2007-03-01

    Mutational activation of the K-Ras oncogene is well established as a key genetic step in the development and growth of pancreatic adenocarcinomas. However, the mechanism by which aberrant Ras signaling promotes uncontrolled pancreatic tumor cell growth remains to be fully elucidated. The recent use of primary human cells to study Ras-mediated oncogenesis provides important model cell systems to dissect this mechanism. We have used a model of telomerase-immortalized human pancreatic duct-derived cells (E6/E7/st) to study mechanisms of Ras growth transformation. First, we found that human papillomavirus E6 and E7 oncogenes, which block the function of the p53 and Rb tumor suppressors, respectively, and SV40 small t antigen were required to allow mutant K-Ras(12D) growth transformation. Second, K-Ras(12D) caused growth transformation in vitro, including enhanced growth rate and loss of density dependency for growth, anchorage independence, and invasion through reconstituted basement membrane proteins, and tumorigenic transformation in vivo. Third, we determined that the Raf, phosphatidylinositol 3-kinase (PI3K), and Ral guanine nucleotide exchange factor effector pathways were activated, although extracellular signal-regulated kinase (ERK) activity was not up-regulated persistently. Finally, pharmacologic inhibition of Raf/mitogen-activated protein kinase/ERK and PI3K signaling impaired K-Ras-induced anchorage-independent growth and invasion. In summary, our studies established, characterized, and validated E6/E7/st cells for the study of Ras-induced oncogenesis.

  10. Retinoic acid modulates rat Ito cell proliferation, collagen, and transforming growth factor beta production.

    PubMed Central

    Davis, B H; Kramer, R T; Davidson, N O

    1990-01-01

    Recent studies suggest that vitamin A plays an inhibitory role with respect to "activation" of the hepatic Ito cell, a likely effector of hepatic fibrogenesis. Ito cell "activation" during fibrogenesis is characterized by a decrease in intracellular vitamin A and an increase in cellular proliferation and collagen production. To explore the hypothesis that retinoids have the capacity to diminish Ito cell activation, cultured Ito cells were exposed to retinoic acid and its effects assessed on three key features: cell proliferation, collagen protein production and mRNA abundance, and transforming growth factor beta protein production. Retinoic acid was 100-1,000X more potent than retinol with respect to inhibition of Ito cell proliferation. Interstitial collagen and transforming growth factor beta production were also reduced by 10(-6) M retinoic acid. The relative abundance of type I collagen mRNA however, was not significantly altered. By contrast, retinoic acid administration to rats caused a marked reduction in the abundance of type I collagen mRNA in both total hepatic and purified Ito cell RNA. The relative abundance of rat hepatic fibronectin or apolipoprotein E mRNA was not significantly altered. These studies demonstrate that retinoic acid can differentially modulate several key features of hepatic fibrogenesis in vitro and in vivo. Images PMID:2254460

  11. Creating Activating Events for Transformative Learning in a Prison Classroom

    ERIC Educational Resources Information Center

    Keen, Cheryl H.; Woods, Robert

    2016-01-01

    In this article, we interpreted, in light of Mezirow's theory of transformative learning, interviews with 13 educators regarding their work with marginalized adult learners in prisons in the northeastern United States. Transformative learning may have been aided by the educators' response to unplanned activating events, humor, and respect, and…

  12. Activation of the JNK pathway is essential for transformation by the Met oncogene.

    PubMed Central

    Rodrigues, G A; Park, M; Schlessinger, J

    1997-01-01

    The Met/Hepatocyte Growth Factor (HGF) receptor tyrosine kinase is oncogenically activated through a rearrangement that creates a hybrid gene Tpr-Met. The resultant chimeric p65(Tpr-Met) protein is constitutively phosphorylated on tyrosine residues in vivo and associates with a number of SH2-containing signaling molecules including the p85 subunit of PI-3 kinase and the Grb2 adaptor protein, which couples receptor tyrosine kinases to the Ras signaling pathway. Mutation of the binding site for Grb2 impairs the ability of Tpr-Met oncoprotein to transform fibroblasts, suggesting that the activation of the Ras/MAP kinase signaling pathway through Grb2 may be essential for cellular transformation. To test this hypothesis dominant-negative mutants of Grb2 with deletions of the SH3 domains were introduced into Tpr-Met transformed fibroblasts. Cells overexpressing the mutants were found to be morphologically reverted and exhibited reduced growth in soft agar. Surprisingly, the Grb2 mutants blocked activation of the JNK/SAPK but not MAP kinase activity induced by the Tpr-Met oncoprotein. Additionally, cells expressing dominant-negative Grb2 mutants had reduced PI-3-kinase activity and dominant-negative mutants of Rac1 blocked both Tpr-Met-induced transformation and activation of JNK. These experiments reveal a novel link between Met and the JNK pathway, which is essential for transformation by this oncogene. PMID:9184210

  13. Increased expression of transforming growth factor α precursors in acute experimental colitis in rats

    PubMed Central

    Hoffmann, P; Zeeh, J; Lakshmanan, J; Wu, V; Procaccino, F; Reinshagen, M; McRoberts, J; Eysselein, V

    1997-01-01

    Background and aim—Epidermal growth factor (EGF) and transforming growth factor α (TGF-α), members of the EGF family of growth factors, protect rat gastric and colonic mucosa against injury. Having shown previously that exogenously applied EGF protects rat colonic mucosa against injury, the aim of the present study was to evaluate the endogenously expressed ligand mediating the protective effect of EGF/TGF-α in vivo. 
Methods—In an experimental model of trinitrobenzene sulphonic acid (TNBS)/ ethanol induced colitis in rats EGF and TGF-α expression was evaluated using a ribonuclease protection assay, northern blot analysis, western blot analysis, and immunohistochemistry. 
Results—TGF-α mRNA increased 3-4 times at 4-8 hours after induction of colitis and returned to control levels within 24 hours. TGF-α immunoreactive protein with a molecular size of about 28kDa representing TGF-α precursors increased markedly after induction of colitis with a peak at 8-12 hours. No fully processed 5.6 kDa TGF-α protein was detected in normal or inflamed colon tissue. Only a weak signal for EGF mRNA expression was detected in the rat colon and no EGF protein was observed by immunohistochemistry or western blot analysis. 
Conclusions—TGF-α precursors are the main ligands for the EGF receptor in acute colitis. It is hypothesised that TGF-α precursors convey the biological activity of endogenous TGF-α peptides during mucosal defence and repair. 

 Keywords: transforming growth factor alpha (TGF-α); epidermal growth factor (EGF); precursor molecules; colitis; rat PMID:9301498

  14. Transforming growth factor alpha and epidermal growth factor levels in bladder cancer and their relationship to epidermal growth factor receptor.

    PubMed Central

    Mellon, J. K.; Cook, S.; Chambers, P.; Neal, D. E.

    1996-01-01

    We have examined levels of epidermal growth factor (EGF) and transforming growth factor alpha (TGF-alpha) in neoplastic and non-neoplastic bladder tissue using a standard radioimmunoassay technique. Tumour samples had much higher TGF-alpha levels compared with EGF and TGF-alpha levels in malignant tissue were significantly higher than in benign bladder samples. There was, in addition, a difference in mean EGF levels from 'normal' bladder samples from non-tumour bearing areas of bladder in patients with bladder cancer compared with 'normal' bladder tissue obtained at the time of organ retrieval surgery. Levels of EGF and TGF-alpha did not correlate with levels of EGF receptor (EGFR) as determined by a radioligand binding method but levels of TGF-alpha > 10 ng gm-1 of tumour tissue did correlate with EGFR positivity defined using immunohistochemistry. These data suggest that TGF-alpha is the likely ligand for EGFR in bladder tumours. PMID:8605103

  15. STUDIES ON THE CHEMISTRY OF THE TRANSFORMING ACTIVITY

    PubMed Central

    Zamenhof, Stephen; Alexander, Hattie E.; Leidy, Grace

    1953-01-01

    The transforming principles of Hemophilus influenzae have been purified by a new method including fractional extraction. The active molecule behaves in these extractions like the bulk of the DNA preparation. The minimal amount of DNA necessary for transformation appeared to be of the same order of magnitude as the amount of DNA in a single cell. Quantitative study has been made of the resistance of transforming activity to various agents. When subjected to heat, the temperature at which the activity starts to decrease corresponds rather closely to the temperature at which the viscosity of the bulk of the DNA preparations starts to decrease. Similar correspondence was found when the transforming principle was subjected to pH changes. This is further evidence that the behavior of the active molecules is similar to the behavior of the average DNA molecule of the preparation. The activity is reduced by exposure to low ionic strength and by dehydration. Desoxyribonuclease in concentrations less than 10–4 γ/cc. is able to destroy the activity; a lag period during which the activity but not the viscosity decreases has been observed. NaNO2 at pH 5.3, HCHO and 10–5 M Fe++ reduce or destroy the activity; the importance of intact amino groups in the DNA molecule for the activity is discussed. Several protein-denaturing, sterilizing, and mutagenic agents have been found to have no effect on the transforming activity. PMID:13096662

  16. v-src transformation of rat embryo fibroblasts. Inefficient conversion to anchorage-independent growth involves heterogeneity of primary cultures

    PubMed Central

    1994-01-01

    To clarify whether a single oncogene can transform primary cells in culture, we compared the transforming effect of a recombinant retrovirus (ZSV) containing the v-src gene in rat embryo fibroblasts (REFs) to that in the rat cell line 3Y1. In the focus assay, REFs exhibited resistance to transformation as only six foci were observed in the primary cultures as opposed to 98 in 3Y1 cells. After G418 selection, efficiency of transformation was again somewhat lower with REFs compared to that with 3Y1 cells, but the number of G418-resistant REF colonies was much greater than the number of foci in REF cultures. Furthermore, while 98% of G418-resistant colonies of ZSV-infected REFs were morphologically transformed, only 25% were converted to anchorage- independent growth, as opposed to 100% conversion seen in ZSV-infected 3Y1 cells. The poor susceptibility of REFs to anchorage-independent transformation did not involve differences in expression and subcellular distribution of p60v-src, or its kinase activity in vitro and in vivo. It rather reflected a property of the primary cultures, as cloning of REFs before ZSV infection demonstrated that only 2 out of 6 REF clones tested were permissive for anchorage-independent growth. The nonpermissive phenotype was dominant over the permissive one in somatic hybrid cells, and associated with organized actin filament bundles and a lower growth rate, both before and after ZSV infection. These results indicate that the poor susceptibility of REFs to anchorage-independent transformation by p60v-src reflects the heterogeneity of the primary cultures. REFs can be morphologically transformed by p60v-src with high efficiency but only a small fraction is convertible to anchorage- independent growth. REF resistance seems to involve the presence of a suppressor factor which may emerge from REF differentiation during embryonic development. PMID:8034746

  17. TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF)

    EPA Science Inventory

    TITLE:
    TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF). AUTHORS (ALL): Abbott, Barbara D.1; Best, Deborah S.1; Narotsky, Michael G.1. SPONSOR NAME: None INSTITUTIONS (ALL): 1. Repro Tox ...

  18. Transforming Staff Practice through Active Support

    ERIC Educational Resources Information Center

    Riches, Vivienne C.; Harman, Anthony D.; Keen, Deb; Pennell, Donna; Harley, Jane H.; Walker, Michelle

    2011-01-01

    Background: Active support is being introduced in many residential and respite homes in an effort to improve engagement in meaningful activity of people with intellectual disability. Method: A train-the-trainer approach was used in a large government organisation that supports people with intellectual disability in Australia. Five apprentice…

  19. Hammerhead Ribozyme-Mediated Knockdown of mRNA for Fibrotic Growth Factors: Transforming Growth Factor-Beta 1 and Connective Tissue Growth Factor

    PubMed Central

    Robinson, Paulette M.; Blalock, Timothy D.; Yuan, Rong; Lewin, Alfred S.; Schultz, Gregory S.

    2013-01-01

    Excessive scarring (fibrosis) is a major cause of pathologies in multiple tissues, including lung, liver, kidney, heart, cornea, and skin. The transforming growth factor- β (TGF- β) system has been shown to play a key role in regulating the formation of scar tissue throughout the body. Furthermore, connective tissue growth factor (CTGF) has been shown to mediate most of the fibrotic actions of TGF- β, including stimulation of synthesis of extracellular matrix and differentiation of fibroblasts into myofibroblasts. Currently, no approved drugs selectively and specifically regulate scar formation. Thus, there is a need for a drug that selectively targets the TGF- β cascade at the molecular level and has minimal off-target side effects. This chapter focuses on the design of hammerhead ribozymes, measurement of kinetic activity, and assessment of knockdown mRNAs of TGF- β and CTGF in cell cultures. PMID:22131029

  20. Chemical transformations that yield compounds with distinct activity profiles.

    PubMed

    Hu, Ye; Bajorath, Jürgen

    2011-07-14

    We have systematically searched for chemical changes that generate compounds with distinct biological activity profiles. For this purpose, activity profiles were generated for ∼42000 compounds active against human targets. Unique activity profiles involving multiple target proteins were determined, and all possible matched molecular pairs (MMPs) were identified for compounds representing these profiles. An MMP is defined as a pair of compounds that are distinguished from each other only at a single site such as an R group or ring system. For example, in an MMP, a hydroxyl group might be replaced by a halogen atom or a benzene ring by an amide group. From ∼37500 MMPs, more than 300 nonredundant chemical transformations were isolated that yielded compounds with distinct activity profiles. None of these transformations was found in pairs of compounds with overlapping activity profiles. These transformations were ranked according to the number of MMPs, the number of activity profiles, and the total number of targets that they covered. In many instances, prioritized transformations involved ring systems of varying complexity. All transformations that were found to switch activity profiles are provided to enable further analysis and aid in compound design efforts.

  1. Attenuated Transforming Growth Factor Beta Signaling as a Therapeutic for Prostate Cancer Progression

    DTIC Science & Technology

    2008-04-01

    upregulates VEGF expression only. Circulation 1994;90:649-52. 4. Igarashi A, Okochi H , Bradham DM, Grotendorst GR. Regulation of connective tissue growth...2005;65:8887-95. 10. Uhl M, Aulwurm S, Wischhusen J, et al. SD-208, a novel transforming growth factor beta receptor I kinase inhibitor, inhibits growth...cancer. Endocr Relat Cancer 2005;12:805-22. 18. Kawada M, Inoue H , Masuda T, Ikeda D. Insulin-like growth factor I secreted from prostate stromal

  2. Transforming growth factor-beta1 mediates cellular response to DNA damage in situ

    NASA Technical Reports Server (NTRS)

    Ewan, Kenneth B.; Henshall-Powell, Rhonda L.; Ravani, Shraddha A.; Pajares, Maria Jose; Arteaga, Carlos; Warters, Ray; Akhurst, Rosemary J.; Barcellos-Hoff, Mary Helen

    2002-01-01

    Transforming growth factor (TGF)-beta1 is rapidly activated after ionizing radiation, but its specific role in cellular responses to DNA damage is not known. Here we use Tgfbeta1 knockout mice to show that radiation-induced apoptotic response is TGF-beta1 dependent in the mammary epithelium, and that both apoptosis and inhibition of proliferation in response to DNA damage decrease as a function of TGF-beta1 gene dose in embryonic epithelial tissues. Because apoptosis in these tissues has been shown previously to be p53 dependent, we then examined p53 protein activation. TGF-beta1 depletion, by either gene knockout or by using TGF-beta neutralizing antibodies, resulted in decreased p53 Ser-18 phosphorylation in irradiated mammary gland. These data indicate that TGF-beta1 is essential for rapid p53-mediated cellular responses that mediate cell fate decisions in situ.

  3. Cripto Binds Transforming Growth Factor β (TGF-β) and Inhibits TGF-β Signaling▿

    PubMed Central

    Gray, Peter C.; Shani, Gidi; Aung, Kevin; Kelber, Jonathan; Vale, Wylie

    2006-01-01

    Cripto is a developmental oncoprotein and a member of the epidermal growth factor-Cripto, FRL-1, Cryptic family of extracellular signaling molecules. In addition to having essential functions during embryogenesis, Cripto is highly expressed in tumors and promotes tumorigenesis. During development, Cripto acts as an obligate coreceptor for transforming growth factor β (TGF-β) ligands, including nodals, growth and differentiation factor 1 (GDF1), and GDF3. As an oncogene, Cripto is thought to promote tumor growth via mechanisms including activation of mitogenic signaling pathways and antagonism of activin signaling. Here, we provide evidence supporting a novel mechanism in which Cripto inhibits the tumor suppressor function of TGF-β. Cripto bound TGF-β and reduced the association of TGF-β with its type I receptor, TβRI. Consistent with its ability to block receptor assembly, Cripto suppressed TGF-β signaling in multiple cell types and diminished the cytostatic effects of TGF-β in mammary epithelial cells. Furthermore, targeted disruption of Cripto expression by use of small inhibitory RNA enhanced TGF-β signaling, indicating that endogenous Cripto plays a role in restraining TGF-β responses. PMID:17030617

  4. Transforming growth factor-beta as a differentiating factor for cultured smooth muscle cells.

    PubMed

    Gawaziuk, J P; X; Sheikh, F; Cheng, Z-Q; Cattini, P A; Stephens, N L

    2007-10-01

    The aim of the present study was to determine whether the development of supercontractile smooth muscle cells, contributing to the nonspecific hyperreactivity of airways in asthmatic patients, is due to transforming growth factor (TGF)-beta. In cultured smooth muscle cells starved by removal of 10% foetal bovine serum for 7 days, growth arrest was seen; 30% became elongated and demonstrated super contractility. Study of conditioned medium suggested that the differentiating factor was TGF-beta. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) was carried out on conditioned medium from the arrested cells. Two protein bands were identified as matrix metalloproteinase (MMP)-2 and TGF-beta1. To determine second messenger signalling by SMAD2, Western blotting and confocal microscopy were employed. Conditioned medium from arrested cultures showed the presence of MMP-2 and TGF-beta1, as revealed by SDS-PAGE; 68- and 25-kDa bands were seen. Differentiation was confirmed by upregulation of marker proteins, smooth muscle type myosin heavy chain and myosin light chain kinase. Confirmation was obtained by downregulating these proteins with decorin treatment, which reduces the levels of active TGF-beta and an adenoviral dominant-negative vector coding for a mutated type II TGF-beta-receptor. Activation of second messenger signalling was demonstrated immunocytochemically by the presence of phosphorylated SMAD2 and SMAD4. Transforming growth factor-beta is likely to be the differentiating factor responsible for the development of these supercontractile smooth muscle cells. The development of such cells in vivo after cessation of an asthmatic attack could contribute to the nonspecific hyperreactivity of airways seen in patients.

  5. Harnessing High Density Lipoproteins to Block Transforming Growth Factor Beta and to Inhibit the Growth of Liver Tumor Metastases

    PubMed Central

    Medina-Echeverz, José; Fioravanti, Jessica; Díaz-Valdés, Nancy; Frank, Kathrin; Aranda, Fernando; Gomar, Celia; Ardaiz, Nuria; Dotor, Javier; Umansky, Viktor; Prieto, Jesús; Berraondo, Pedro

    2014-01-01

    Transforming growth factor β (TGF-β) is a powerful promoter of cancer progression and a key target for antitumor therapy. As cancer cells exhibit active cholesterol metabolism, high density lipoproteins (HDLs) appear as an attractive delivery system for anticancer TGFβ-inhibitory molecules. We constructed a plasmid encoding a potent TGF-β-blocking peptide (P144) linked to apolipoprotein A-I (ApoA-I) through a flexible linker (pApoLinkerP144). The ApoLinkerP144 sequence was then incorporated into a hepatotropic adeno-associated vector (AAVApoLinkerP144). The aim was to induce hepatocytes to produce HDLs containing a modified ApoA-I capable of blocking TGF-β. We observed that transduction of the murine liver with pApoLinkerP144 led to the appearance of a fraction of circulating HDL containing the fusion protein. These HDLs were able to attenuate TGF-β signaling in the liver and to enhance IL-12 -mediated IFN-γ production. Treatment of liver metastasis of MC38 colorectal cancer with AAVApoLinkerP144 resulted in a significant reduction of tumor growth and enhanced expression of IFN-γ and GM-CSF in cancerous tissue. ApoLinkerP144 also delayed MC38 liver metastasis in Rag2−/−IL2rγ−/− immunodeficient mice. This effect was associated with downregulation of TGF-β target genes essential for metastatic niche conditioning. Finally, in a subset of ret transgenic mice, a model of aggressive spontaneous metastatic melanoma, AAVApoLinkerP144 delayed tumor growth in association with increased CD8+ T cell numbers in regional lymph nodes. In conclusion, modification of HDLs to transport TGF-β-blocking molecules is a novel and promising approach to inhibit the growth of liver metastases by immunological and non-immunological mechanisms. PMID:24797128

  6. Inhibition of transforming growth factor β signaling promotes epiblast formation in mouse embryos.

    PubMed

    Ghimire, Sabitri; Heindryckx, Björn; Van der Jeught, Margot; Neupane, Jitesh; O'Leary, Thomas; Lierman, Sylvie; De Vos, Winnok H; Chuva de Sousa Lopes, Susana; Deroo, Tom; De Sutter, Petra

    2015-02-15

    Early lineage segregation in preimplantation embryos and maintenance of pluripotency in embryonic stem cells (ESCs) are both regulated by specific signaling pathways. Small molecules have been shown to modulate these signaling pathways. We examined the influence of several small molecules and growth factors on second-lineage segregation of the inner cell mass toward hypoblast and epiblast lineage during mouse embryonic preimplantation development. We found that the second-lineage segregation is influenced by activation or inhibition of the transforming growth factor (TGF)β pathway. Inhibition of the TGFβ pathway from the two-cell, four-cell, and morula stages onward up to the blastocyst stage significantly increased the epiblast cell proliferation. The epiblast formed in the embryos in which TGFβ signaling was inhibited was fully functional as demonstrated by the potential of these epiblast cells to give rise to pluripotent ESCs. Conversely, activating the TGFβ pathway reduced epiblast formation. Inhibition of the glycogen synthase kinase (GSK)3 pathway and activation of bone morphogenetic protein 4 signaling reduced the formation of both epiblast and hypoblast cells. Activation of the protein kinase A pathway and of the Janus kinase/signal transducer and activator of transcription 3 pathway did not influence the second-lineage segregation in mouse embryos. The simultaneous inhibition of three pathways--TGFβ, GSK3β, and the fibroblast growth factor (FGF)/extracellular signal-regulated kinases (Erk)--significantly enhanced the proliferation of epiblast cells than that caused by inhibition of either TGFβ pathway alone or by combined inhibition of the GSK3β and FGF/Erk pathways only.

  7. Parabens enable suspension growth of MCF-10A immortalized, non-transformed human breast epithelial cells.

    PubMed

    Khanna, Sugandha; Darbre, Philippa D

    2013-05-01

    Parabens (alkyl esters of p-hydroxybenzoic acid) are used extensively as preservatives in consumer products, and intact esters have been measured in several human tissues. Concerns of a potential link between parabens and breast cancer have been raised, but mechanistic studies have centred on their oestrogenic activity and little attention has been paid to any carcinogenic properties. In the present study, we report that parabens can induce anchorage-independent growth of MCF-10A immortalized but non-transformed human breast epithelial cells, a property closely related to transformation and a predictor of tumour growth in vivo. In semi-solid methocel suspension culture, MCF-10A cells produced very few colonies and only of a small size but the addition of 5 × 10(-4) M methylparaben, 10(-5) M n-propylparaben or 10(-5) M n-butylparaben resulted in a greater number of colonies per dish (P < 0.05 in each case) and an increased average colony size (P < 0.001 in each case). Dose-responses showed that concentrations as low as 10(-6) M methylparaben, 10(-7) M n-propylparaben and 10(-7) M n-butylparaben could increase colony numbers (P = 0.016, P = 0.010, P = 0.008, respectively): comparison with a recent measurement of paraben concentrations in human breast tissue samples from 40 mastectomies (Barr et al., 2012) showed that 22/40 of the patients had at least one of the parabens at the site of the primary tumour at or above these concentrations. To our knowledge, this is the first study to report that parabens can induce a transformed phenotype in human breast epithelial cells in vitro, and further investigation is now justified into a potential link between parabens and breast carcinogenesis.

  8. [Cytogenetic activity of the butylcaptax defoliant transformation product].

    PubMed

    Vesmanova, O Ia; Semykina, E E; Koblov, R K; Ergashev

    1989-01-01

    Cytogenetical activity of the product of metabolitic butylcaptax transformations in cells of cotton plants G. barbadense has been studied. It is shown that butylcaptax, with a significant mutagenicity, looses its mutagenic activity, metabolizing in low mutagenic 2-oxyamylthiobenzthiazole. Low water solubility prevents its concentration to exceed 0.005% in tissue liquids and to exert a mutagenic action on cotton plants.

  9. Transforming growth factor beta1 regulates melanocyte proliferation and differentiation in mouse neural crest cells via stem cell factor/KIT signaling.

    PubMed

    Kawakami, Tamihiro; Soma, Yoshinao; Kawa, Yoko; Ito, Masaru; Yamasaki, Emiko; Watabe, Hidenori; Hosaka, Eri; Yajima, Kenji; Ohsumi, Kayoko; Mizoguchi, Masako

    2002-03-01

    Stem cell factor is essential to the migration and differentiation of melanocytes during embryogenesis based on the observation that mutations in either the stem cell factor gene, or its ligand, KIT, result in defects in coat pigmentation in mice. Stem cell factor is also required for the survival of melanocyte precursors while they are migrating towards the skin. Transforming growth factor beta1 has been implicated in the regulation of both cellular proliferation and differentiation. NCC-melb4, an immortal cloned cell line, was cloned from a mouse neural crest cell. NCC-melb4 cells provide a model to study the specific stage of differentiation and proliferation of melanocytes. They also express KIT as a melanoblast marker. Using the NCC-melb4 cell line, we investigated the effect of transforming growth factor beta1 on the differentiation and proliferation of immature melanocyte precursors. Immunohistochemically, NCC-melb4 cells showed transforming growth factor beta1 expression. The anti-transforming growth factor beta1 antibody inhibited the cell growth, and downregulated the KIT protein and mRNA expression. To investigate further the activation of autocrine transforming growth factor beta1, NCC-melb4 cells were incubated in nonexogenous transforming growth factor beta1 culture medium. KIT protein decreased with anti-transforming growth factor beta1 antibody concentration in a concentration-dependent manner. We concluded that in NCC-melb4 cells, transforming growth factor beta1 promotes melanocyte precursor proliferation in autocrine and/or paracrine regulation. We further investigated the influence of transforming growth factor beta1 in vitro using a neural crest cell primary culture system from wild-type mice. Anti-transforming growth factor beta1 antibody decreased the number of KIT positive neural crest cell. In addition, the anti-transforming growth factor beta1 antibody supplied within the wild-type neural crest explants abolished the growth of the neural

  10. Requirement of Stat3 but not Stat1 activation for epidermal growth factor receptor- mediated cell growth In vitro.

    PubMed Central

    Grandis, J R; Drenning, S D; Chakraborty, A; Zhou, M Y; Zeng, Q; Pitt, A S; Tweardy, D J

    1998-01-01

    Stimulation of epidermal growth factor receptor (EGFR) by ligand(s) leads to activation of signaling molecules including Stat1 and Stat3, two members of the signal transducers and activators of transcription (STAT) protein family. Activation of Stat1 and Stat3 was constitutive in transformed squamous epithelial cells, which produce elevated levels of TGF-alpha, and was enhanced by the addition of exogenous TGF-alpha. Targeting of Stat3 using antisense oligonucleotides directed against the translation initiation site, resulted in significant growth inhibition. In addition, cells stably transfected with dominant negative mutant Stat3 constructs failed to proliferate in vitro. In contrast, targeting of Stat1 using either antisense or dominant-negative strategies had no effect on cell growth. Thus, TGF-alpha/EGFR-mediated autocrine growth of transformed epithelial cells is dependent on activation of Stat3 but not Stat1. PMID:9769331

  11. Potassium inhibits dietary salt-induced transforming growth factor-beta production.

    PubMed

    Ying, Wei-Zhong; Aaron, Kristal; Wang, Pei-Xuan; Sanders, Paul W

    2009-11-01

    Human and animal studies demonstrate an untoward effect of excess dietary NaCl (salt) intake on cardiovascular function and life span. The endothelium in particular augments the production of transforming growth factor (TGF)-beta, a fibrogenic growth factor, in response to excess dietary salt intake. This study explored the initiating mechanism that regulates salt-induced endothelial cell production of TGF-beta. Male Sprague-Dawley rats were given diets containing different amounts of NaCl and potassium for 4 days. A bioassay for TGF-beta demonstrated increased (35.2%) amounts of active TGF-beta in the medium of aortic ring segments from rats on the high-salt diet compared with rats maintained on a 0.3% NaCl diet. Inhibition of the large-conductance, calcium-activated potassium channel inhibited dietary salt-induced vascular production of TGF-beta but did not affect production of TGF-beta by ring segments from rats on the low-salt diet. Immunohistochemical and Western analyses demonstrated the alpha subunit of the calcium-activated potassium channel in endothelial cells. Increasing medium [K+] inhibited production of dietary salt-induced vascular production levels of total and active TGF-beta but did not alter TGF-beta production by aortic rings from rats on the 0.3% NaCl diet. Increasing dietary potassium content decreased urinary active TGF-beta in animals receiving the high-salt diet but did not change urinary active TGF-beta in animals receiving the low-salt diet. The findings demonstrated an interesting interaction between the dietary intake of potassium and excess NaCl and further showed the fundamental role of the endothelial calcium-activated potassium channel in the vascular response to excess salt intake.

  12. Potassium Inhibits Dietary Salt-Induced Transforming Growth Factor-β Production

    PubMed Central

    Ying, Wei-Zhong; Aaron, Kristal; Wang, Pei-Xuan; Sanders, Paul W.

    2009-01-01

    Human and animal studies demonstrate an untoward effect of excess dietary NaCl (salt) intake on cardiovascular function and life span. The endothelium in particular augments the production of transforming growth factor (TGF)-β, a fibrogenic growth factor, in response to excess dietary salt intake. This study explored the initiating mechanism that regulates salt-induced endothelial cell production of TGF-β. Male Sprague-Dawley rats were given diets containing different amounts of NaCl and potassium for 4 days. A bioassay for TGF-β demonstrated increased (35.2%) amounts of active TGF-β in the medium of aortic ring segments from rats on the high-salt diet compared with rats maintained on a 0.3% NaCl diet. Inhibition of the large-conductance, calcium-activated potassium channel inhibited dietary salt-induced vascular production of TGF-β but did not affect production of TGF-β by ring segments from rats on the low-salt diet. Immunohistochemical and Western analyses demonstrated the α subunit of the calcium-activated potassium channel in endothelial cells. Increasing medium [K+] inhibited production of dietary salt-induced vascular production levels of total and active TGF-β but did not alter TGF-β production by aortic rings from rats on the 0.3% NaCl diet. Increasing dietary potassium content decreased urinary active TGF-β in animals receiving the high-salt diet but did not change urinary active TGF-β in animals receiving the low-salt diet. The findings demonstrated an interesting interaction between the dietary intake of potassium and excess NaCl and further showed the fundamental role of the endothelial calcium-activated potassium channel in the vascular response to excess salt intake. PMID:19738156

  13. Genetic Analysis of Connective Tissue Growth Factor as an Effector of Transforming Growth Factor β Signaling and Cardiac Remodeling

    PubMed Central

    Accornero, Federica; van Berlo, Jop H.; Correll, Robert N.; Elrod, John W.; Sargent, Michelle A.; York, Allen; Rabinowitz, Joseph E.; Leask, Andrew

    2015-01-01

    The matricellular secreted protein connective tissue growth factor (CTGF) is upregulated in response to cardiac injury or with transforming growth factor β (TGF-β) stimulation, where it has been suggested to function as a fibrotic effector. Here we generated transgenic mice with inducible heart-specific CTGF overexpression, mice with heart-specific expression of an activated TGF-β mutant protein, mice with heart-specific deletion of Ctgf, and mice in which Ctgf was also deleted from fibroblasts in the heart. Remarkably, neither gain nor loss of CTGF in the heart affected cardiac pathology and propensity toward early lethality due to TGF-β overactivation in the heart. Also, neither heart-specific Ctgf deletion nor CTGF overexpression altered cardiac remodeling and function with aging or after multiple acute stress stimuli. Cardiac fibrosis was also unchanged by modulation of CTGF levels in the heart with aging, pressure overload, agonist infusion, or TGF-β overexpression. However, CTGF mildly altered the overall cardiac response to TGF-β when pressure overload stimulation was applied. CTGF has been proposed to function as a critical TGF-β effector in underlying tissue remodeling and fibrosis throughout the body, although our results suggest that CTGF is of minimal importance and is an unlikely therapeutic vantage point for the heart. PMID:25870108

  14. Role of transforming growth factor-beta (TGF) beta in the physiopathology of rheumatoid arthritis.

    PubMed

    Gonzalo-Gil, Elena; Galindo-Izquierdo, María

    2014-01-01

    Transforming growth factor-beta (TGF-β) is a cytokine with pleiotropic functions in hematopoiesis, angiogenesis, cell proliferation, differentiation, migration and apoptosis. Although its role in rheumatoid arthritis is not well defined, TGF-β activation leads to functional immunomodulatory effects according to environmental conditions. The function of TGF-β in the development of arthritis in murine models has been extensively studied with controversial results. Recent findings point to a non-relevant role for TGF-β in a mice model of collagen-induced arthritis. The study of TGF-β on T-cell responses has shown controversial results as an inhibitor or promoter of the inflammatory response. This paper presents a review of the role of TGF-β in animal models of arthritis.

  15. Effect of Cellulose Acetate Beads on the Release of Transforming Growth Factor-β.

    PubMed

    Nishise, Shoichi; Abe, Yasuhiko; Nomura, Eiki; Sato, Takeshi; Sasaki, Yu; Iwano, Daisuke; Yagi, Makoto; Sakuta, Kazuhiro; Shibuya, Rika; Mizumoto, Naoko; Kanno, Nana; Ueno, Yoshiyuki

    2015-08-01

    Transforming growth factor-β (TGF-β) is released by activated platelets and induces the differentiation of T-helper 17 from naïve T cells. Contact between blood and cellulose acetate (CA) beads induces cytokine release, although their inflammatory effects on TGF-β release are unclear. We aimed to clarify the effect of CA beads on the release of TGF-β in vitro. We incubated peripheral blood with and without CA beads and measured platelets and TGF-β. Compared with blood samples incubated without beads, the platelet count and amount of TGF-β significantly decreased in blood samples incubated with CA beads. In conclusion, CA beads inhibited the release of TGF-β from adsorbed platelets. The biological effects of this reduction of TGF-β release during platelet adsorption to CA beads need further clarification.

  16. Connective tissue growth factor/CCN2-null mouse embryonic fibroblasts retain intact transforming growth factor-{beta} responsiveness

    SciTech Connect

    Mori, Yasuji; Hinchcliff, Monique; Wu, Minghua; Warner-Blankenship, Matthew; Lyons, Karen M.

    2008-03-10

    Background: The matricellular protein connective tissue growth factor (CCN2) has been implicated in pathological fibrosis, but its physiologic role remains elusive. In vitro, transforming growth factor-{beta} (TGF-{beta}) induces CCN2 expression in mesenchymal cells. Because CCN2 can enhance profibrotic responses elicited by TGF-{beta}, it has been proposed that CCN2 functions as an essential downstream signaling mediator for TGF-{beta}. To explore this notion, we characterized TGF-{beta}-induced activation of fibroblasts from CCN2-null (CCN2{sup -/-}) mouse embryos. Methods: The regulation of CCN2 expression was examined in vivo in a model of fibrosis induced by bleomycin. Cellular TGF-{beta} signal transduction and regulation of collagen gene expression were examined in CCN2{sup -/-} MEFs by immunohistochemistry, Northern, Western and RT-PCR analysis, immunocytochemistry and transient transfection assays. Results: Bleomycin-induced skin fibrosis in the mouse was associated with substantial CCN2 up-regulation in lesional fibroblasts. Whereas in vitro proliferation rate of CCN2{sup -/-} MEFs was markedly reduced compared to wild type MEFs, TGF-{beta}-induced activation of the Smad pathways, including Smad2 phosphorylation, Smad2/3 and Smad4 nuclear accumulation and Smad-dependent transcriptional responses, were unaffected by loss of CCN2. The stimulation of COL1A2 and fibronectin mRNA expression and promoter activity, and of corresponding protein levels, showed comparable time and dose-response in wild type and CCN2{sup -/-} MEFs, whereas stimulation of alpha smooth muscle actin and myofibroblast transdifferentiation showed subtle impairment in MEFs lacking CCN2. Conclusion: Whereas endogenous CCN2 plays a role in regulation of proliferation and TGF-{beta}-induced myofibroblast transdifferentiation, it appears to be dispensable for Smad-dependent stimulation of collagen and extracellular matrix synthesis in murine embryonic fibroblasts.

  17. Pin1 promotes transforming growth factor-beta-induced migration and invasion.

    PubMed

    Matsuura, Isao; Chiang, Keng-Nan; Lai, Chen-Yu; He, Dongming; Wang, Guannan; Ramkumar, Romila; Uchida, Takafumi; Ryo, Akihide; Lu, Kunping; Liu, Fang

    2010-01-15

    Transforming growth factor-beta (TGF-beta) regulates a wide variety of biological activities. It induces potent growth-inhibitory responses in normal cells but promotes migration and invasion of cancer cells. Smads mediate the TGF-beta responses. TGF-beta binding to the cell surface receptors leads to the phosphorylation of Smad2/3 in their C terminus as well as in the proline-rich linker region. The serine/threonine phosphorylation sites in the linker region are followed by the proline residue. Pin1, a peptidyl-prolyl cis/trans isomerase, recognizes phosphorylated serine/threonine-proline motifs. Here we show that Smad2/3 interacts with Pin1 in a TGF-beta-dependent manner. We further show that the phosphorylated threonine 179-proline motif in the Smad3 linker region is the major binding site for Pin1. Although epidermal growth factor also induces phosphorylation of threonine 179 and other residues in the Smad3 linker region the same as TGF-beta, Pin1 is unable to bind to the epidermal growth factor-stimulated Smad3. Further analysis suggests that phosphorylation of Smad3 in the C terminus is necessary for the interaction with Pin1. Depletion of Pin1 by small hairpin RNA does not significantly affect TGF-beta-induced growth-inhibitory responses and a number of TGF-beta/Smad target genes analyzed. In contrast, knockdown of Pin1 in human PC3 prostate cancer cells strongly inhibited TGF-beta-mediated migration and invasion. Accordingly, TGF-beta induction of N-cadherin, which plays an important role in migration and invasion, is markedly reduced when Pin1 is depleted in PC3 cells. Because Pin1 is overexpressed in many cancers, our findings highlight the importance of Pin1 in TGF-beta-induced migration and invasion of cancer cells.

  18. Valproic acid overcomes transforming growth factor-β-mediated sorafenib resistance in hepatocellular carcinoma

    PubMed Central

    Matsuda, Yasunobu; Wakai, Toshifumi; Kubota, Masayuki; Osawa, Mami; Hirose, Yuki; Sakata, Jun; Kobayashi, Takashi; Fujimaki, Shun; Takamura, Masaaki; Yamagiwa, Satoshi; Aoyagi, Yutaka

    2014-01-01

    Sorafenib is a multi-kinase inhibitor approved for hepatocellular carcinoma, but rarely causes tumor regression in patients with chronic liver diseases. To investigate whether growth factor-mediated signaling is involved in sorafenib resistance, HepG2 and PLC/PRF/5 hepatoma cells were exposed to epidermal growth factor (EGF), hepatocyte growth factor (HGF) or transforming growth factor-β (TGF-β) prior to treatment with sorafenib. Furthermore, to identify an effective combination treatment with sorafenib, growth factor-sensitized cells were treated with sorafenib alone or in combination with celecoxib, lovastatin or valproic acid (VPA). Trypan blue staining and Annexin V assays showed that the cytotoxic effect of sorafenib was inhibited by 15-54% in cells sensitized to TGF-β (P<0.05). Western blotting analysis showed that TGF-β significantly activated extracellular signal-regulated kinase (ERK)-mediated AKT signaling, and sorafenib failed to suppress both ERK and AKT in TGF-β-sensitized cells. The decreased anti-tumor effect of sorafenib was rescued by chemical inhibition of ERK and AKT. When TGF-β-sensitized cells were treated with sorafenib plus VPA, the levels of phosphorylated ERK and AKT were considerably suppressed and the numbers of dead cells were increased by 3.7-5.7-fold compared with those exposed to sorafenib alone (P<0.05). Moreover, low dose sorafenib-induced cell migration was effectively suppressed by combination treatment with sorafenib and VPA. Collectively, TGF-β/ERK/AKT signaling might play a critical role in sorafenib resistance in hepatoma cells, and combination treatment with VPA may be effective against this drug resistance. PMID:24817927

  19. Inhibition of spermidine synthase gene expression by transforming growth factor-beta 1 in hepatoma cells.

    PubMed Central

    Nishikawa, Y; Kar, S; Wiest, L; Pegg, A E; Carr, B I

    1997-01-01

    We screened genes responsive to transforming growth factor-beta (TGF-beta 1) protein in a human hepatoma cell line (Hep3B) using a PCR-mediated differential display technique, in order to investigate the mechanisms involved in TGF-beta-induced growth suppression. We found a gene that was down-regulated by TGF-beta 1 to be completely identical in an approx. 620 bp segment to the gene for the enzyme spermidine synthase, which mediates the conversion of putrescine into spermidine. Both spermidine synthase mRNA expression and its enzyme activity were decreased after TGF-beta 1 treatment of Hep3B cells. The inhibition of spermidine synthase gene expression by TGF-beta 1 protein was also observed in other hepatoma cell lines. The expression of genes for other biosynthetic enzymes in polyamine metabolism (ornithine decarboxylase and S-adenosylmethionine decarboxylase) was also inhibited to the same extent as for spermidine synthase, while the gene expression of spermidine/spermine N1-acetyltransferase, a catabolic enzyme, was relatively resistant to TGF-beta 1. Spermine levels in Hep3B cells were decreased by TGF-beta 1 treatment, although the levels of spermidine and putrescine were unchanged, probably due to compensation by remaining spermidine/spermine N1-acetyltransferase activity. Exogenously added spermidine or spermine, but not putrescine, partially antagonized the growth-inhibitor effects of TGF-beta 1 on Hep3B cells. Our data suggest that down-regulation of gene expression of the enzymes involved in polyamine metabolism, including spermidine synthase, may be associated with the mechanism of TGF-beta-induced growth suppression. PMID:9020892

  20. Dependence of Dbl and Dbs Transformation on MEK and NF-κB Activation

    PubMed Central

    Whitehead, Ian P.; Lambert, Que T.; Glaven, Judith A.; Abe, Karon; Rossman, Kent L.; Mahon, Gwendolyn M.; Trzaskos, James M.; Kay, Robert; Campbell, Sharon L.; Der, Channing J.

    1999-01-01

    Dbs was identified initially as a transforming protein and is a member of the Dbl family of proteins (>20 mammalian members). Here we show that Dbs, like its rat homolog Ost and the closely related Dbl, exhibited guanine nucleotide exchange activity for the Rho family members RhoA and Cdc42, but not Rac1, in vitro. Dbs transforming activity was blocked by specific inhibitors of RhoA and Cdc42 function, demonstrating the importance of these small GTPases in Dbs-mediated growth deregulation. Although Dbs transformation was dependent upon the structural integrity of its pleckstrin homology (PH) domain, replacement of the PH domain with a membrane localization signal restored transforming activity. Thus, the PH domain of Dbs (but not Dbl) may be important in modulating association with the plasma membrane, where its GTPase substrates reside. Both Dbs and Dbl activate multiple signaling pathways that include activation of the Elk-1, Jun, and NF-κB transcription factors and stimulation of transcription from the cyclin D1 promoter. We found that Elk-1 and NF-κB, but not Jun, activation was necessary for Dbl and Dbs transformation. Finally, we have observed that Dbl and Dbs regulated transcription from the cyclin D1 promoter in a NF-κB-dependent manner. Previous studies have dissociated actin cytoskeletal activity from the transforming potential of RhoA and Cdc42. These observations, when taken together with those of the present study, suggest that altered gene expression, and not actin reorganization, is the critical mediator of Dbl and Rho family protein transformation. PMID:10523665

  1. Platelet-derived growth factor-dependent cellular transformation requires either phospholipase Cgamma or phosphatidylinositol 3 kinase.

    PubMed

    DeMali, K A; Whiteford, C C; Ulug, E T; Kazlauskas, A

    1997-04-04

    Although it has been well established that constitutive activation of receptor tyrosine kinases leads to cellular transformation, the signal relay pathways involved have not been systematically investigated. In this study we used a panel of platelet-derived growth factor (PDGF) beta receptor mutants (beta-PDGFR), which selectively activate various signal relay enzymes to define which signaling pathways are required for PDGF-dependent growth of cells in soft agar. The host cell line for these studies was Ph cells, a 3T3-like cell that expresses normal levels of the beta-PDGFR but no PDGF-alpha receptor (alpha-PDGFR). Hence, this cell system can be used to study signaling of mutant alphaPDGFRs or alpha/beta chimeras. We constructed chimeric receptors containing the alphaPDGFR extracellular domain and the betaPDGFR cytoplasmic domain harboring various phosphorylation site mutations. The mutants were expressed in Ph cells, and their ability to drive PDGF-dependent cellular transformation (growth in soft agar) was assayed. Cells infected with an empty expression vector failed to grow in soft agar, whereas introduction of the chimera with a wild-type beta-PDGFR cytoplasmic domain gave rise to a large number of colonies. In contrast, the N2F5 chimera, in which the binding sites for phospholipase Cgamma (PLC-gamma), RasGTPase-activating protein, phosphatidylinositol 3 kinase (PI3K), and SHP-2 were eliminated, failed to trigger proliferation. Restoring the binding sites for RasGTPase-activating protein or SHP-2 did not rescue the PDGF-dependent response. In contrast, receptors capable of associating with either PLC-gamma or PI3K relayed a growth signal that was comparable to wild-type receptors in the soft agar growth assay. These findings indicate that the PDGF receptor activates multiple signaling pathways that lead to cellular transformation, and that either PI3K or PLC-gamma are key initiators of such signal relay cascades.

  2. Molecular and functional characterization of goldfish (Carassius auratus L.) transforming growth factor beta.

    PubMed

    Haddad, George; Hanington, Patrick C; Wilson, Elaine C; Grayfer, Leon; Belosevic, Miodrag

    2008-01-01

    Transforming growth factor beta (TGF-beta) is a pleiotropic cytokine with important roles in the regulation of cell proliferation, differentiation, survival, migration, activation and de-activation. It is one of the first cytokines released during an immune response and plays a strong immunomodulatory role in the activation and subsequent de-activation of macrophages and other immune cells. TGF-beta is a highly conserved molecule, and members of the TGF superfamily can be found in organisms as evolutionarily distant as arthropods. In this manuscript, we described the identification of a goldfish TGF-beta molecule, which was highly expressed in the skin, kidney and spleen of the goldfish and its expression was up-regulated in macrophages treated with LPS or recombinant goldfish TNF-alpha. Goldfish TGF-beta shared a high amino acid identity with, and was phylogenetically related to, TGF-beta1 of other teleost fish, birds, amphibians and mammals. Recombinant goldfish TGF-beta (rTGF-beta) induced the proliferation of a goldfish fibroblast cell line (CCL71) in a dose-dependent manner. In addition, rTGF-beta down-regulated the nitric oxide response of TNF-alpha-activated macrophages. This is the first report of teleost TGF-beta function in an ectothermic vertebrate.

  3. The role of transforming growth factor-beta, insulin-like growth factor I, and basic fibroblast growth factor in distraction osteogenesis of the mandible.

    PubMed

    Farhadieh, R D; Dickinson, R; Yu, Y; Gianoutsos, M P; Walsh, W R

    1999-01-01

    Distraction osteogenesis is a viable method for regenerating large amounts of bone. In contrast to fracture healing, the mode of bone formation in distraction osteogenesis is primarily intramembranous ossification. The basic biology of the process is still not well understood. The growth factor cascade is likely to play an important role in distraction. This study examines the growth factor cascade in a lengthened ovine mandible model. Twenty-four animals were divided into four groups with varying rates of distraction (1, 2, 3, and 4 mm/day). A unilateral distractor at the angle of the mandible was used. The mandibles were lengthened to 24 mm and fixed for a period of 5 weeks, after which the animals were killed. The sections were probed for transforming growth factor-beta, basic fibroblast growth factor, and insulin-like growth factor I. The growth factors studied were present in all four groups. Transforming growth factor-beta, basic fibroblast growth factor, and insulin-like growth factor I were present in both the bony matrix of the sections and the cytoplasm of the cells, osteoblasts, and a small number of mesenchymal cells. The sections obtained from groups distracted at faster rates showed stronger presence of the growth factors examined by more intense staining. In fracture healing, the localization of transforming growth factor-beta in stage I of healing corresponded with the precise region of intramembranous ossification in stage II. Diffuse presence of transforming growth factor-beta throughout the lengthened region corresponded with the process of intramembranous ossification observed in distraction. In fracture healing, insulin-like growth factor I and basic fibroblast growth factor have been shown to promote proliferation and differentiation of osteoblasts from precursor cells. The intense presence of insulin-like growth factor I and basic fibroblast growth factor in the distracted region may account for osteoblast proliferation and formation from

  4. Transformation of fraud activities in procurement system in Indonesia

    NASA Astrophysics Data System (ADS)

    Setiani, N.; Huda, S. N.; Pulungan, R.; Winarko, E.

    2017-03-01

    E-procurement has been applied in Indonesia since 2008 through the adoption of Electronic Procurement System (SPSE). The purpose of the use of SPSE in the procurement process is to improve the efficiency of goods or services procurement. In the bidding process, intensive communication and data exchange between providers and organizers are urgently needed. Through SPSE, the frequency of face to face meetings between providers and the committee can be reduced. This is expected to minimize potential fraud behaviors in the goods or services procurement conducted through the tender process. There exists a transformation of activities in the procurement through SPSE from the tender process that was previously done manually. In this paper, we analyze this transformation between manual procurement process and SPSE-based procurement process. The result of the analysis is exploited for investigating the possibility of fraud behavior transformations in every phase of e-procurement activities.

  5. Substrate flexibility regulates growth and apoptosis of normal but not transformed cells

    NASA Technical Reports Server (NTRS)

    Wang, H. B.; Dembo, M.; Wang, Y. L.

    2000-01-01

    One of the hallmarks of oncogenic transformation is anchorage-independent growth (27). Here we demonstrate that responses to substrate rigidity play a major role in distinguishing the growth behavior of normal cells from that of transformed cells. We cultured normal or H-ras-transformed NIH 3T3 cells on flexible collagen-coated polyacrylamide substrates with similar chemical properties but different rigidity. Compared with cells cultured on stiff substrates, nontransformed cells on flexible substrates showed a decrease in the rate of DNA synthesis and an increase in the rate of apoptosis. These responses on flexible substrates are coupled to decreases in cell spreading area and traction forces. In contrast, transformed cells maintained their growth and apoptotic characteristics regardless of substrate flexibility. The responses in cell spreading area and traction forces to substrate flexibility were similarly diminished. Our results suggest that normal cells are capable of probing substrate rigidity and that proper mechanical feedback is required for regulating cell shape, cell growth, and survival. The loss of this response can explain the unregulated growth of transformed cells.

  6. Structure-function analysis of synthetic and recombinant derivatives of transforming growth factor alpha.

    PubMed Central

    Defeo-Jones, D; Tai, J Y; Wegrzyn, R J; Vuocolo, G A; Baker, A E; Payne, L S; Garsky, V M; Oliff, A; Riemen, M W

    1988-01-01

    Transforming growth factor alpha (TGF-alpha) is a 50-amino-acid peptide that stimulates cell proliferation via binding to cell surface receptors. To identify the structural features of TGF-alpha that govern receptor-ligand interactions, we prepared synthetic peptide fragments and recombinant mutant proteins of TGF-alpha. These TGF-alpha derivatives were tested in receptor binding and mitogenesis assays. Synthetic peptides representing the N terminus, the C terminus, or the individual disulfide constrained rings of TGF-alpha did not exhibit receptor-binding or mitogenic activity. Replacement of the cysteines with alanines at positions 8 and 21, 16 and 32, and 34 and 43 or at positions 8 and 21 and 34 and 43 yielded inactive mutant proteins. However, mutant proteins containing substitutions or deletions in the N-terminal region retained significant biologic activity. Conservative amino acid changes at residue 29 or 38 or both and a nonconservative amino acid change at residue 12 had little effect on binding or mitogenesis. However, nonconservative amino acid changes at residues 15, 38, and 47 produced dramatic decreases in receptor binding (23- to 71-fold) and mitogenic activity (38- to 125-fold). These studies indicate that at least three distinct regions of TGF-alpha contribute to biologic activity. PMID:2850475

  7. RhoA Modulates Smad Signaling during Transforming Growth Factor-β-induced Smooth Muscle Differentiation*

    PubMed Central

    Chen, Shiyou; Crawford, Michelle; Day, Regina M.; Briones, Victorino R.; Leader, Jennifer E.; Jose, Pedro A.; Lechleider, Robert J.

    2007-01-01

    We recently reported that transforming growth factor (TGF)-β induced the neural crest stem cell line Monc-1 to differentiate into a spindle-like contractile smooth muscle cell (SMC) phenotype and that Smad signaling played an important role in this phenomenon. In addition to Smad signaling, other pathways such as mitogen-activated protein kinase (MAPK), phosphoinositol-3 kinase, and RhoA have also been shown to mediate TGF-β actions. The objectives of this study were to examine whether these signaling pathways contribute to TGF-β-induced SMC development and to test whether Smad signaling cross-talks with other pathway(s) during SMC differentiation induced by TGF-β. We demonstrate here that RhoA signaling is critical to TGF-β-induced SMC differentiation. RhoA kinase (ROCK) inhibitor Y27632 significantly blocks the expression of multiple SMC markers such as smooth muscle α-actin, SM22α, and calponin in TGF-β-treated Monc-1 cells. In addition, Y27632 reversed the cell morphology and abolished the contractility of TGF-β-treated cells. RhoA signaling was activated as early as 5 min following TGF-β addition. Dominant negative RhoA blocked nuclear translocation of Smad2 and Smad3 because of the inhibition of phosphorylation of both Smads and inhibited Smad-dependent SBE promoter activity, whereas constitutively active RhoA significantly enhanced SBE promoter activity. Consistent with these results, C3 exotoxin, an inhibitor of RhoA activation, significantly attenuated SBE promoter activity and inhibited Smad nuclear translocation. Taken together, these data point to a new role for RhoA as a modulator of Smad activation while regulating TGF-β-induced SMC differentiation. PMID:16317010

  8. Transforming growth factor-beta1 to the bone.

    PubMed

    Janssens, Katrien; ten Dijke, Peter; Janssens, Sophie; Van Hul, Wim

    2005-10-01

    TGF-beta1 is a ubiquitous growth factor that is implicated in the control of proliferation, migration, differentiation, and survival of many different cell types. It influences such diverse processes as embryogenesis, angiogenesis, inflammation, and wound healing. In skeletal tissue, TGF-beta1 plays a major role in development and maintenance, affecting both cartilage and bone metabolism, the latter being the subject of this review. Because it affects both cells of the osteoblast and osteoclast lineage, TGF-beta1 is one of the most important factors in the bone environment, helping to retain the balance between the dynamic processes of bone resorption and bone formation. Many seemingly contradictory reports have been published on the exact functioning of TGF-beta1 in the bone milieu. This review provides an overall picture of the bone-specific actions of TGF-beta1 and reconciles experimental discrepancies that have been reported for this multifunctional cytokine.

  9. Nitric oxide synthase inhibitors attenuate transforming-growth-factor-beta 1-stimulated capillary organization in vitro.

    PubMed Central

    Papapetropoulos, A.; Desai, K. M.; Rudic, R. D.; Mayer, B.; Zhang, R.; Ruiz-Torres, M. P.; García-Cardeña, G.; Madri, J. A.; Sessa, W. C.

    1997-01-01

    Angiogenesis is a complex process involving endothelial cell (EC) proliferation, migration, differentiation, and organization into patent capillary networks. Nitric oxide (NO), an EC mediator, has been reported to be antigenic as well as proangiogenic in different models of in vivo angiogenesis. Our aim was to investigate the role of NO in capillary organization using rat microvascular ECs (RFCs) grown in three-dimensional (3D) collagen gels. RFCs placed in 3D cultures exhibited extensive tube formation in the presence of transforming growth factor-beta 1. Addition of the NO synthase (NOS) inhibitors L-nitro-arginine methylester (L-NAME, 1 mmol/L) or L-monomethyl-nitro-l-arginine (1 mmol/L) inhibited tube formation and the accumulation of nitrite in the media by approximately 50%. Incubation of the 3D cultures with excess L-arginine reversed the inhibitory effect of L-NAME on tube formation. In contrast to the results obtained in 3D cultures, inhibition of NO synthesis by L-NAME did not influence RFC proliferation in two-dimensional (2D) cultures or antagonize the ability of transforming growth factor-beta 1 to suppress EC proliferation in 2D cultures. Reverse transcriptase-polymerase chain reaction revealed the constitutive expression of all three NOS isoforms, neuronal, inducible, and endothelial NOSs, in 2D and 3D cultures. Moreover, Western blot analysis demonstrated the presence of immunoreactive protein for all NOS isoforms in 3D cultures of RFCs. In addition, in the face of NOS blockade, co-treatment with the NO donor sodium nitroprusside or the stable analog of cGMP, 8-bromo-cGMP, restored capillary tube formation. Thus, the autocrine production of NO and the activation of soluble guanylate cyclase are necessary events in the process of differentiation and in vitro capillary tube organization of RFCs. Images Figure 2 Figure 4 Figure 5 PMID:9137106

  10. Transforming growth factor-beta during carcinogenesis: the shift from epithelial to mesenchymal signaling.

    PubMed

    Matsuzaki, Koichi; Okazaki, Kazuichi

    2006-04-01

    Transforming growth factor-beta (TGF-beta) activates not only TGF-beta type I receptor (TbetaRI) but also c-Jun N-terminal kinase (JNK), changing unphosphorylated Smad3 to its phosphoisoforms: C-terminally phosphorylated Smad3 (pSmad3C) and linker phosphorylated Smad3 (pSmad3L). While the TbetaRI/pSmad3C pathway inhibits growth of normal epithelial cells, JNK/pSmad3L-mediated signaling is involved in invasion by activated mesenchymal cells. During sporadic human colorectal carcinogenesis, TGF-beta signaling confers a selective advantage on tumor cells by shifting from the TbetaRI/pSmad3C pathway characteristic of mature epithelial cells to the JNK/pSmad3L pathway, which is more characteristic of the state of flux shown by the activated mesenchymal cells. JNK acts as a regulator of TGF-beta signaling by increasing the basal level of pSmad3L available for action in the nuclei of the invasive adenocarcinoma, in the meantime shutting down TGF-beta-dependent nuclear activity of pSmad3C. Loss of epithelial homeostasis and acquisition of a migratory, mesenchymal phenotype are essential for tumor invasion. From the viewpoint of TGF-beta signaling, a key therapeutic aim in cancer would be restoration of the lost tumor suppressor function observed in normal colorectal epithelial cells at the expense of effects promoting aggressive behavior of the adenocarcinoma. Specific inhibitors of the JNK/pSmad3L pathway might prove useful in this respect. In the case of molecularly targeted therapy for human cancer, pSmad3L and pSmad3C could be assessed as biomarkers to evaluate the likely benefit from specific inhibition of the JNK/pSmad3L pathway.

  11. Learning Activities for the Growth Season.

    ERIC Educational Resources Information Center

    Darby, Linda, Ed.

    This poster, illustrated with a graphic of a caterpillar changing to a cocoon and emerging as a butterfly, presents learning activities for 7 weeks based on the seven stages of growth in the President's "Call to Action." Each week includes 5 days of activities based on seven themes: (1) "Reading on Your Own"; (2) "Getting…

  12. Transforming growth factor-beta receptor requirements for the induction of the endothelin-1 gene.

    PubMed

    Castañares, Cristina; Redondo-Horcajo, Mariano; Magan-Marchal, Noemi; Lamas, Santiago; Rodriguez-Pascual, Fernando

    2006-06-01

    Expression of the endothelin (ET)-1 gene is subject to complex regulation by numerous factors, among which the cytokine transforming growth factor-beta (TGF-beta) is one of the most important. TGF-beta action is based on the activation of the Smad signaling pathway. Smad proteins activate transcription of the gene by cooperation with activator protein-1 (AP-1) at specific sites on the ET-1 promoter. Smad signaling pathway is initiated by binding of the cytokine to a heteromeric complex of type I and type II receptors. Signal is then propagated to the nucleus by specific members of the Smad family. Most cell types contain a type I receptor known as ALK5. However, endothelial cells are unique because they coexpress an additional type I receptor named ALK1. These forms do not constitute redundant receptors with the same function, but they actually activate different Smad-mediated expression programs that lead to specific endothelial phenotypes. TGF-beta/ALK5/Smad3 pathway is associated to a mature endothelium because it leads to inhibition of cell migration/proliferation. Conversely, TGF-beta/ALK1/Smad5 activates both processes and is more related to the angiogenic state. We have analyzed the TGF-beta receptor subtype requirements for the activation of the ET-1 gene. For that purpose, we have overexpressed type I receptor and Smad isoforms in endothelial cells and analyzed the effect on ET-1 expression. Our experiments indicate that TGF-beta induces ET-1 expression preferentially through the activation of the ALK5/Smad3 pathway and, therefore, the expression of the vaso-constrictor may be associated to a quiescent and mature endothelial phenotype.

  13. The growth and transformation of American ego psychology.

    PubMed

    Wallerstein, Robert S

    2002-01-01

    The roots of ego psychology trace back to Sigmund Freud's The Ego and the Id (1923) and "Inhibitions, Symptoms and Anxiety" (1926), works followed by two additional fundaments, Anna Freud's The Ego and the Mechanisms of Defense (1936) and Heinz Hartmann's Ego Psychology and the Problem of Adaptation (1939). It was brought to full flowering in post-World War II America by Hartmann and his many collaborators, and for over two decades it maintained a monolithic hegemony over American psychoanalysis. Within this framework the conceptions of the psychoanalytic psychotherapies evolved as specific modifications of psychoanalytic technique directed to the clinical needs of the spectrum of patients not amenable to psychoanalysis proper. This American consensus on the ego psychology paradigm and its array of technical implementations fragmented several decades ago, with the rise in America of Kohut's self psychology, geared to the narcissistic disorders, and with the importation from Britain of neo-Kleinian and object-relational perspectives, all coinciding with the rapid growth of the varieties of relational psychoanalysis, with its shift in focus to the two-person, interactive, and co-constructed transference-countertransference matrix. Implications of this intermingled theoretical pluralism (as contrasted with the unity of the once dominant ego psychology paradigm) for the evolution of the American ego psychology are spelled out.

  14. Demonstration of single crystal growth via solid-solid transformation of a glass.

    PubMed

    Savytskii, Dmytro; Knorr, Brian; Dierolf, Volkmar; Jain, Himanshu

    2016-03-18

    Many advanced technologies have relied on the availability of single crystals of appropriate material such as silicon for microelectronics or superalloys for turbine blades. Similarly, many promising materials could unleash their full potential if they were available in a single crystal form. However, the current methods are unsuitable for growing single crystals of these oftentimes incongruently melting, unstable or metastable materials. Here we demonstrate a strategy to overcome this hurdle by avoiding the gaseous or liquid phase, and directly converting glass into a single crystal. Specifically, Sb2S3 single crystals are grown in Sb-S-I glasses as an example of this approach. In this first unambiguous demonstration of an all-solid-state glass → crystal transformation, extraneous nucleation is avoided relative to crystal growth via spatially localized laser heating and inclusion of a suitable glass former in the composition. The ability to fabricate patterned single-crystal architecture on a glass surface is demonstrated, providing a new class of micro-structured substrate for low cost epitaxial growth, active planar devices, etc.

  15. Demonstration of single crystal growth via solid-solid transformation of a glass

    PubMed Central

    Savytskii, Dmytro; Knorr, Brian; Dierolf, Volkmar; Jain, Himanshu

    2016-01-01

    Many advanced technologies have relied on the availability of single crystals of appropriate material such as silicon for microelectronics or superalloys for turbine blades. Similarly, many promising materials could unleash their full potential if they were available in a single crystal form. However, the current methods are unsuitable for growing single crystals of these oftentimes incongruently melting, unstable or metastable materials. Here we demonstrate a strategy to overcome this hurdle by avoiding the gaseous or liquid phase, and directly converting glass into a single crystal. Specifically, Sb2S3 single crystals are grown in Sb-S-I glasses as an example of this approach. In this first unambiguous demonstration of an all-solid-state glass → crystal transformation, extraneous nucleation is avoided relative to crystal growth via spatially localized laser heating and inclusion of a suitable glass former in the composition. The ability to fabricate patterned single-crystal architecture on a glass surface is demonstrated, providing a new class of micro-structured substrate for low cost epitaxial growth, active planar devices, etc. PMID:26988919

  16. Demonstration of single crystal growth via solid-solid transformation of a glass

    NASA Astrophysics Data System (ADS)

    Savytskii, Dmytro; Knorr, Brian; Dierolf, Volkmar; Jain, Himanshu

    2016-03-01

    Many advanced technologies have relied on the availability of single crystals of appropriate material such as silicon for microelectronics or superalloys for turbine blades. Similarly, many promising materials could unleash their full potential if they were available in a single crystal form. However, the current methods are unsuitable for growing single crystals of these oftentimes incongruently melting, unstable or metastable materials. Here we demonstrate a strategy to overcome this hurdle by avoiding the gaseous or liquid phase, and directly converting glass into a single crystal. Specifically, Sb2S3 single crystals are grown in Sb-S-I glasses as an example of this approach. In this first unambiguous demonstration of an all-solid-state glass → crystal transformation, extraneous nucleation is avoided relative to crystal growth via spatially localized laser heating and inclusion of a suitable glass former in the composition. The ability to fabricate patterned single-crystal architecture on a glass surface is demonstrated, providing a new class of micro-structured substrate for low cost epitaxial growth, active planar devices, etc.

  17. Demonstration of single crystal growth via solid-solid transformation of a glass

    DOE PAGES

    Savytskii, Dmytro; Knorr, Brian; Dierolf, Volkmar; ...

    2016-03-18

    Many advanced technologies have relied on the availability of single crystals of appropriate material such as silicon for microelectronics or superalloys for turbine blades. Similarly, many promising materials could unleash their full potential if they were available in a single crystal form. However, the current methods are unsuitable for growing single crystals of these oftentimes incongruently melting, unstable or metastable materials. Here we demonstrate a strategy to overcome this hurdle by avoiding the gaseous or liquid phase, and directly converting glass into a single crystal. Specifically, Sb2S3 single crystals are grown in Sb-S-I glasses as an example of this approach.more » In this first unambiguous demonstration of an all-solid-state glass → crystal transformation, extraneous nucleation is avoided relative to crystal growth via spatially localized laser heating and inclusion of a suitable glass former in the composition. Lastly, the ability to fabricate patterned single-crystal architecture on a glass surface is demonstrated, providing a new class of micro-structured substrate for low cost epitaxial growth, active planar devices, etc.« less

  18. Demonstration of single crystal growth via solid-solid transformation of a glass

    SciTech Connect

    Savytskii, Dmytro; Knorr, Brian; Dierolf, Volkmar; Jain, Himanshu

    2016-03-18

    Many advanced technologies have relied on the availability of single crystals of appropriate material such as silicon for microelectronics or superalloys for turbine blades. Similarly, many promising materials could unleash their full potential if they were available in a single crystal form. However, the current methods are unsuitable for growing single crystals of these oftentimes incongruently melting, unstable or metastable materials. Here we demonstrate a strategy to overcome this hurdle by avoiding the gaseous or liquid phase, and directly converting glass into a single crystal. Specifically, Sb2S3 single crystals are grown in Sb-S-I glasses as an example of this approach. In this first unambiguous demonstration of an all-solid-state glass → crystal transformation, extraneous nucleation is avoided relative to crystal growth via spatially localized laser heating and inclusion of a suitable glass former in the composition. Lastly, the ability to fabricate patterned single-crystal architecture on a glass surface is demonstrated, providing a new class of micro-structured substrate for low cost epitaxial growth, active planar devices, etc.

  19. Curcumin Inhibits Transforming Growth Factor β Induced Differentiation of Mouse Lung Fibroblasts to Myofibroblasts

    PubMed Central

    Liu, Daishun; Gong, Ling; Zhu, Honglan; Pu, Shenglan; Wu, Yang; Zhang, Wei; Huang, Guichuan

    2016-01-01

    Transforming growth factor β (TGF-β) induced differentiation of lung fibroblasts to myofibroblasts is a key event in the pathogenesis of pulmonary fibrosis. This study aimed to evaluate the effect of curcumin on TGF-β induced differentiation of lung fibroblasts to myofibroblasts and explore the underlying mechanism. Mouse lung fibroblasts were cultured and treated with TGF-β2 and curcumin or rosiglitazone. Cell vitality was examined by MTT assay. The secretion of collagen-1 was assessed by ELISA. α smooth muscle actin (α-SMA) was visualized by immunofluorescence technique. The expression of peroxisome proliferator activated receptor γ (PPAR-γ) and platelet derived growth factor R β (PDGFR-β) was detected by PCR and Western blot analysis. We found that curcumin and rosiglitazone inhibited the proliferation and TGF-β induced differentiation of mouse lung fibroblasts. In addition, curcumin and rosiglitazone inhibited collagen-1 secretion and α-SMA expression in mouse lung fibroblasts. Furthermore, curcumin and rosiglitazone upregulated PPAR-γ and downregulated PDGFR-β expression in mouse lung fibroblasts. In conclusion, our study reveals novel mechanism by which curcumin inhibits TGF-β2 driven differentiation of lung fibroblasts to myofibroblasts. Curcumin could potentially be used for effective treatment of pulmonary fibrosis. PMID:27877129

  20. Theory of Crystal Growth, Kinetics of Dissolution and Transformation of Calcium Phosphates.

    NASA Astrophysics Data System (ADS)

    Zhang, Jingwu

    The kink density along a (01) step on the (001) face of a Kossel crystal is derived from a kinetic steady state approach by considering the elementary events at the step. When the kink formation energy, epsilon , is very high compared with the thermal energy kT, the kink density, rho, is found to be a function of the saturation ratio, S. For S > 1, rho = 2a-1S^ {1over 2}exp(-epsilon /kT) while for S < 1, rho = 2a^{-1}exp( -epsilon/kT)/(2-S)^ {1over 2}. This finding may provide a theoretical background for interpreting the observed growth kinetics of many sparingly soluble salts in aqueous solutions. The above approach is extended to analyze the configuration of a surface step of an AB crystal with NaCl type of lattice. It is found that the growth rate of an electrolyte crystal cannot be defined solely by the thermodynamic driving forces even when integration is the rate determining step. The rate also depends on the lattice ion activity ratio and relative frequencies of integration of A and B ions into kink sites on a step. At a given driving force, a maximum growth rate can be attained at a certain ratio of lattice ion activities. The dual constant composition (DCC) method is developed which enables the kinetics of phase transformation to be studied at constant driving forces. The applicability of this novel approach is verified in the investigation of dicalcium phosphate dihydrate (DCPD) to octacalcium phosphate (OCP) transformation. In these studies, the concentrations of total calcium and phosphate are maintained constant to within 2% with the pH held to within +/-0.003 during the reaction. The dissolution kinetics of DCPD and OCP has been investigated using CC method at 37^circ C over a wide range of experimental conditions. Both processes can be generally described by a combined volume and surface diffusion mechanism with varying degrees of volume resistance at different pH's and solution hydrodynamics. The decrease in the dissolution rate with the extent of

  1. Endogenous GABAA receptor activity suppresses glioma growth.

    PubMed

    Blanchart, A; Fernando, R; Häring, M; Assaife-Lopes, N; Romanov, R A; Andäng, M; Harkany, T; Ernfors, P

    2017-02-09

    Although genome alterations driving glioma by fueling cell malignancy have largely been resolved, less is known of the impact of tumor environment on disease progression. Here, we demonstrate functional GABAA receptor-activated currents in human glioblastoma cells and show the existence of a continuous GABA signaling within the tumor cell mass that significantly affects tumor growth and survival expectancy in mouse models. Endogenous GABA released by tumor cells, attenuates proliferation of the glioma cells with enriched expression of stem/progenitor markers and with competence to seed growth of new tumors. Our results suggest that GABA levels rapidly increase in tumors impeding further growth. Thus, shunting chloride ions by a maintained local GABAA receptor activity within glioma cells has a significant impact on tumor development by attenuating proliferation, reducing tumor growth and prolonging survival, a mechanism that may have important impact on therapy resistance and recurrence following tumor resection.

  2. Detecting transforming growth factor-β release from liver cells using an aptasensor integrated with microfluidics.

    PubMed

    Matharu, Zimple; Patel, Dipali; Gao, Yandong; Haque, Amranul; Zhou, Qing; Revzin, Alexander

    2014-09-02

    We developed a cell-culture/biosensor platform consisting of aptamer-modified Au electrodes integrated with reconfigurable microfluidics for monitoring of transforming growth factor-beta 1 (TGF-β1), an important inflammatory and pro-fibrotic cytokine. Aptamers were thiolated, labeled with redox reporters, and self-assembled on gold surfaces. The biosensor was determined to be specific for TGF-β1 with an experimental detection limit of 1 ng/mL and linear range extending to 250 ng/mL. Upon determining figures of merit, aptasensor was miniaturized and integrated with human hepatic stellate cells inside microfluidic devices. Reconfigurable microfluidics were developed to ensure that seeding of "sticky" stromal cells did not foul the electrode and compromise sensor performance. This microsystem with integrated aptasensors was used to monitor TGF-β1 release from activated stellate cells over the course of 20 h. The electrochemical response went down upon infusing anti-TGF-β1 antibodies into the microfluidic devices containing activated stellate cells. To further validate aptasensor responses, stellate cells were stained for markers of activation (e.g., alpha smooth muscle actin) and were also tested for presence of TGF-β1 using enzyme linked immunosorbent assay (ELISA). Given the importance of TGF-β1 as a fibrogenic signal, a microsystem with integrated biosensors for local and continuous detection of TGF-β1 may prove to be an important tool to study fibrosis of the liver and other organs.

  3. Aerobic activated sludge transformation of methotrexate: identification of biotransformation products.

    PubMed

    Kosjek, Tina; Negreira, Noelia; de Alda, Miren López; Barceló, Damià

    2015-01-01

    This study describes the biotransformation of cytostatic and immunosuppressive pharmaceutical methotrexate. Its susceptibility to microbiological breakdown was studied in a batch biotransformation system, in presence or absence of carbon source and at two activated sludge concentrations. The primary focus of the present study are methotrexate biotransformation products, which were tentatively identified by the ultra-high performance liquid chromatography-quadrupole--Orbitrap-MS. Data-dependent experiments, combining full-scan MS data with product ion spectra were acquired, in order to identify the molecular ions of methotrexate transformation products, to propose the molecular formulae and to elucidate their chemical structures. Among the identified transformation products 2,4-diamino-N10-methyl-pteroic acid is most abundant and persistent. Other biotransformation reactions involve demethylation, oxidative cleavage of amine, cleavage of C-N bond, aldehyde to carboxylate transformation and hydroxylation. Finally, a breakdown pathway is proposed, which shows that most of methotrexate breakdown products retain the diaminopteridine structural segment. In total we propose nine transformation products, among them eight are described as methotrexate transformation products for the first time.

  4. Differential effects of transforming growth factor type beta on the growth and function of adrenocortical cells in vitro.

    PubMed Central

    Hotta, M; Baird, A

    1986-01-01

    Transforming growth factor type beta (TGF-beta) suppresses basal as well as corticotropin (ACTH)-stimulated steroid formation by bovine adrenocortical cells in culture. The effect is dose dependent and is not accompanied by any change in adrenocortical cell growth. The minimum effective dose of TGF-beta is 4 X 10(-13) M (10 pg/ml), and maximal inhibition is observed at a concentration of 4 X 10(-11) M (1 ng/ml). A 16- to 20-hr incubation with TGF-beta is required to decrease steroidogenesis, and 12-18 hr are required before cells treated with TGF-beta recover complete responsiveness to corticotropin. Increases in cAMP mediated by corticotropin, forskolin, and isobutylmethylxanthine are not modified by the addition of TGF-beta; thus adenylate cyclase activity is unaffected by TGF-beta. Although TGF-beta inhibits the formation of all of the delta 4-steroids measured (including cortisol, corticosterone, aldosterone, and androstenedione), its effect can be completely reversed by the addition of 25-hydroxycholesterol, pregnenolone, or progesterone to the cells. In contrast, the addition of low density lipoprotein has no effect suggesting that TGF-beta targets the conversion of cholesterol precursors to cholesterol. The results demonstrate a highly potent effect of TGF-beta on the differentiated function of the adrenocortical cell. The inhibition of steroidogenesis can be dissociated from any effect on cell proliferation, and it occurs distal to the formation of cAMP but proximal to the formation of cholesterol. The results suggest that in the adrenal, TGF-beta or TGF-beta-like proteins may be playing an important role in modifying the differentiated state of the adrenocortical cell. PMID:3020557

  5. Intracellular processing of transforming growth factor-beta in mesangial cells.

    PubMed

    Ceol, M; Vianello, D; Baggio, B; Meani, A; Schleicher, E; Anglani, F; Gambaro, G

    1998-03-01

    Transforming growth factor beta 1 (TGF-beta 1) is a multifunctional regulator of cell-growth, differentiation and extracellular matrix formation in several physiological conditions. It plays a crucial role in the process of glomerulosclerosis. Mature TGF-beta 1 is secreted as a latent form associated with the latency associated peptide (LAP), and its activation occurs through the LAP cleavage. The intracellular localization and the mechanisms of activation of TGF-beta 1 protein have not been elucidated in the mesangial cell. In the present report we examined the intracellular processing from TGF-beta 1 precursor to the latent-TGF-beta 1 in cultured mesangial cells by immunocytochemistry, using three rabbit polyclonal antibodies directed against different epitopes of human TGF-beta 1. The anti-LAP-TGF-beta 1 precursor Ab stained mesangial cells in the perinuclear region and in the cytoplasm in the area corresponding to the rough endoplasmic reticulum; the anti-COOH-terminal fragment of TGF-beta 1 Ab reacted in the same area, in vesicular structures located in the cytoplasm and furthermore, in the mesangial cell clusters, so-called hillocks, with an extracellular pattern; the anti-NH2-terminal fragment of TGF-beta 1 Ab stained only large exocytotic vesicles at the periphery of the cytoplasma. Our investigations suggest a conformational rearrangement of pro-TGF-beta 1 molecule occurring between the rough endoplasmic reticulum and the TGF-beta 1 secretion and support the idea that in mesangial cells the activation of TGF-beta 1 occurs during the secretion process. In conclusion, the processing of TGF-beta 1 in mesangial cells seems to be similar to that one observed in other mesenchymal cells.

  6. Effects of transforming growth factor-beta on growth and differentiation of the continuous rat thyroid follicular cell line, FRTL-5

    SciTech Connect

    Morris, J.C. III; Ranganathan, G.; Hay, I.D.; Nelson, R.E.; Jiang, N.S.

    1988-09-01

    Transforming growth factor-beta (TGF beta) has been shown to influence the growth and differentiation of many widely varied cell types in vitro, including some that are endocrinologically active. We have investigated the previously unknown effects of this unique growth factor in the differentiated rat thyroid follicular cell line FRTL-5. The cells demonstrated specific, high affinity binding of TGF beta, and as with other epithelial cells, the growth of these thyroid follicular cells was potently inhibited by addition of TGF beta to the culture medium. TGF beta caused a significant reduction in TSH-sensitive adenylate cyclase activity in the cells. The addition of (Bu)2cAMP along with the growth factor to cultures partially reversed the characteristic morphological changes seen with TGF beta, but did not reverse the growth inhibition. To further investigate the possible mechanisms of the effects of TGF beta on the cells, we measured the influence of the growth factor on (125I)TSH binding. TGF beta did not compete for specific TSH-binding sites; however, exposure of the cells to TGF beta for 12 or more h resulted in a dose-dependent down-regulation of TSH receptors that was fully reversible. While cellular proliferation was potently inhibited by TGF beta, differentiated function, as manifest by iodine-trapping ability, was stimulated by the growth factor. This stimulation of iodine uptake was independent of, and additive to, the stimulatory effects of TSH. Finally, FRTL-5 cells in serum-free medium and in response to TSH were shown to secrete TGF beta-like activity that competed for (125I)TGF beta in a RRA. These studies suggest that TGF beta may represent an autocrine mechanism of controlling the growth response to TSH in thyroid follicular cells, while allowing the continuance of differentiated function.

  7. Quantitative assessment of growth plate activity

    SciTech Connect

    Harcke, H.T.; Macy, N.J.; Mandell, G.A.; MacEwen, G.D.

    1984-01-01

    In the immature skeleton the physis or growth plate is the area of bone least able to withstand external forces and is therefore prone to trauma. Such trauma often leads to premature closure of the plate and results in limb shortening and/or angular deformity (varus or valgus). Active localization of bone seeking tracers in the physis makes bone scintigraphy an excellent method for assessing growth plate physiology. To be most effective, however, physeal activity should be quantified so that serial evaluations are accurate and comparable. The authors have developed a quantitative method for assessing physeal activity and have applied it ot the hip and knee. Using computer acquired pinhole images of the abnormal and contralateral normal joints, ten regions of interest are placed at key locations around each joint and comparative ratios are generated to form a growth plate profile. The ratios compare segmental physeal activity to total growth plate activity on both ipsilateral and contralateral sides and to adjacent bone. In 25 patients, ages 2 to 15 years, with angular deformities of the legs secondary to trauma, Blount's disease, and Perthes disease, this technique is able to differentiate abnormal segmental physeal activity. This is important since plate closure does not usually occur uniformly across the physis. The technique may permit the use of scintigraphy in the prediction of early closure through the quantitative analysis of serial studies.

  8. On-line Monitoring and Active Control for Transformer Noise

    NASA Astrophysics Data System (ADS)

    Liang, Jiabi; Zhao, Tong; Tian, Chun; Wang, Xia; He, Zhenhua; Duan, Lunfeng

    This paper introduces the system for on-line monitoring and active noise control towards the transformer noise based on LabVIEW and the hardware equipment including the hardware and software. For the hardware part, it is mainly focused on the composition and the role of hardware devices, as well as the mounting location in the active noise control experiment. And the software part introduces the software flow chats, the measurement and analysis module for the sound pressure level including A, B, C weighting methods, the 1/n octave spectrum and the power spectrum, active noise control module and noise data access module.

  9. Inactivation of Smad-Transforming Growth Factor β Signaling by Ca2+-Calmodulin-Dependent Protein Kinase II

    PubMed Central

    Wicks, Stephen J.; Lui, Stephen; Abdel-Wahab, Nadia; Mason, Roger M.; Chantry, Andrew

    2000-01-01

    Members of the transforming growth factor β (TGF-β) family transduce signals through Smad proteins. Smad signaling can be regulated by the Ras/Erk/mitogen-activated protein pathway in response to receptor tyrosine kinase activation and the gamma interferon pathway and also by the functional interaction of Smad2 with Ca2+-calmodulin. Here we report that Smad–TGF-β-dependent transcriptional responses are prevented by expression of a constitutively activated Ca2+-calmodulin-dependent protein kinase II (Cam kinase II). Smad2 is a target substrate for Cam kinase II in vitro at serine-110, -240, and -260. Cam kinase II induces in vivo phosphorylation of Smad2 and Smad4 and, to a lesser extent, Smad3. A phosphopeptide antiserum raised against Smad2 phosphoserine-240 reacted with Smad2 in vivo when coexpressed with Cam kinase II and by activation of the platelet-derived growth factor receptor, the epidermal growth factor receptor, HER2 (c-erbB2), and the TGF-β receptor. Furthermore, Cam kinase II blocked nuclear accumulation of a Smad2 and induced Smad2-Smad4 hetero-oligomerization independently of TGF-β receptor activation, while preventing TGF-β-dependent Smad2-Smad3 interactions. These findings provide a novel cross-talk mechanism by which Ca2+-dependent kinases activated downstream of multiple growth factor receptors antagonize cell responses to TGF-β. PMID:11027280

  10. Cloning the promoter for transforming growth factor-beta type III receptor. Basal and conditional expression in fetal rat osteoblasts

    NASA Technical Reports Server (NTRS)

    Ji, C.; Chen, Y.; McCarthy, T. L.; Centrella, M.

    1999-01-01

    Transforming growth factor-beta binds to three high affinity cell surface molecules that directly or indirectly regulate its biological effects. The type III receptor (TRIII) is a proteoglycan that lacks significant intracellular signaling or enzymatic motifs but may facilitate transforming growth factor-beta binding to other receptors, stabilize multimeric receptor complexes, or segregate growth factor from activating receptors. Because various agents or events that regulate osteoblast function rapidly modulate TRIII expression, we cloned the 5' region of the rat TRIII gene to assess possible control elements. DNA fragments from this region directed high reporter gene expression in osteoblasts. Sequencing showed no consensus TATA or CCAAT boxes, whereas several nuclear factors binding sequences within the 3' region of the promoter co-mapped with multiple transcription initiation sites, DNase I footprints, gel mobility shift analysis, or loss of activity by deletion or mutation. An upstream enhancer was evident 5' proximal to nucleotide -979, and a silencer region occurred between nucleotides -2014 and -2194. Glucocorticoid sensitivity mapped between nucleotides -687 and -253, whereas bone morphogenetic protein 2 sensitivity co-mapped within the silencer region. Thus, the TRIII promoter contains cooperative basal elements and dispersed growth factor- and hormone-sensitive regulatory regions that can control TRIII expression by osteoblasts.

  11. Modulation of enzymatic activity of Src-family kinases in bovine T cells transformed by Theileria parva.

    PubMed

    Fich, C; Klauenberg, U; Fleischer, B; Bröker, B M

    1998-08-01

    After infection with sporozoites of the protozoon Theileria parva (Tp) bovine T cells are readily transformed to permanent growth in vivo and in vitro. Their transformed state depends on the constant presence of the parasite but membrane signals remain important. Non-receptor tyrosine kinases play a critical role in the transduction of membrane signals in haematopoietic cells. We have investigated Src-family kinases in bovine T cells transformed by Tp. The T cell receptor-associated tyrosine kinase p60fyn had high activity in all cell lines tested. In addition, weak phosphorylation of 2 novel bands was observed associated with Fyn. In contrast to Fyn, enzymatic activity of p56lck, which in T cells has an essential role in signalling, was low. Furthermore, 1 of 3 Tp transformed cell lines was completely devoid of p56lck indicating that the enzyme is not necessary for the Tp dependent growth of the T cells. In addition to p60fyn and p56lck weak enzymatic activity of 1 splice variant of p53/56lyn was observed after infection of T cells with Tp. These data show that growth transformation by Tp influences kinase activity in bovine T cells. However, they also prove that p56lck does not play an essential role in the transformation mechanism.

  12. Transforming growth factor-beta stimulates the expression of fibronectin by human keratinocytes.

    PubMed

    Wikner, N E; Persichitte, K A; Baskin, J B; Nielsen, L D; Clark, R A

    1988-09-01

    Transforming growth factor beta (TGF-beta) is a 25-kD protein which has regulatory activity over a variety of cell types. It is distinct from epidermal growth factor (EGF) and EGF analogs, and exerts its action via a distinct receptor. Its effect on proliferation or differentiation can be positive or negative depending on the cell type and the presence of other growth factors. It also modulates the expression of cellular products. TGF-beta causes fibroblasts to increase their production of the extracellular matrix components, fibronectin and collagen. Human keratinocytes (HK) are known to have TGF-beta receptors. We wished to study the effect of TGF-beta on the production of extracellular matrix proteins by human keratinocytes in culture. Human keratinocytes were grown in serum-free defined medium (MCDB-153) to about 70% confluence. Following a 16-h incubation in medium lacking EGF and TGF-beta, cells were incubated for 12 h in medium containing varying concentrations of EGF and TGF-beta. Cells were then labeled with 35S-methionine for 10 h in the same conditions. Labeled proteins from the medium were analyzed by SDS-PAGE and autoradiography. TGF-beta at 10 ng/ml induced a sixfold increase in the secretion of fibronectin, as well as an unidentified 50-kD protein. Thrombospondin production was also increased, but not over a generalized twofold increase in the production of all other proteins. EGF, at 10 ng/ml, caused a smaller additive effect. TGF-beta may be an important stimulator of extracellular matrix production by human keratinocytes.

  13. Reverse Austenite Transformation and Grain Growth in a Low-Carbon Steel

    NASA Astrophysics Data System (ADS)

    Garcin, Thomas; Ueda, Keiji; Militzer, Matthias

    2017-02-01

    The mechanisms controlling the reverse austenite transformation and the subsequent grain growth are examined in a low-carbon steel during slow continuous heating. The ex-situ metallographic analysis of quenched samples is complemented by in-situ dilatometry of the phase transformation and real-time laser ultrasonic measurements of the austenite grain size. Although the initial state of the microstructure (bainite or martensite) has only limited impact on the austenite transformation temperature, it has significant influence on the mean austenite grain size and the rate of grain growth. The coarsening of austenite islands during reverse transformation occurring from the martensitic microstructure is responsible for a large austenite grain structure at the completion of the austenite formation. On the other hand, a much finer austenite grain size is obtained when the austenite transforms from the bainite microstructure. Upon further heating, the rate of austenite grain growth is limited by the presence of nanometric precipitates present in the bainite microstructure leading to a significantly finer austenite grain size. These results give important guidance for the design of thermomechanical-controlled processing of heavy-gage steel plates.

  14. Calycosin inhibits migration and invasion through modulation of transforming growth factor beta-mediated mesenchymal properties in U87 and U251 cells

    PubMed Central

    Nie, Xiao-hu; Ou-yang, Jia; Xing, Ying; Li, Dan-yan; Liu, Ru-en; Xu, Ru-xiang

    2016-01-01

    In this study, we investigated the potential anticancer effects of calycosin against human glioblastoma cells, including the impacts on cell proliferation, apoptosis, and cell cycle distribution. We further studied its inhibitory activity on migration and invasion in U87 and U251 cells. Furthermore, transforming growth factor beta-mediated reductions of mesenchymal-associated genes/activators, matrix metalloproteinases-2, and -9 were detected in this process. Administration of calycosin in a glioblastoma xenograft model showed that calycosin could not only reduce tumor volume but also suppress transforming growth factor beta as well as its downstream molecules. These results revealed calycosin as a potential antitumor agent in human glioblastoma. PMID:26955262

  15. Autocrine Transforming Growth Factor-β Growth Pathway in Murine Osteosarcoma Cell Lines Associated with Inability to Affect Phosphorylation of Retinoblastoma Protein

    PubMed Central

    Letterio, John J.; Yeung, Choh L.; Pegtel, Michiel; Helman, Lee J.

    2000-01-01

    Purpose. Production of active transforming growth factor-β (TGF-β ) by human osteosarcoma may contribute to malignant progression through mechanisms that include induction of angiogenesis, immune suppression and autocrine growth stimulation of tumor cell growth.To study events associated with induction of cell proliferation by TGF-β , we have evaluated the TGF-β pathway in two murine osteosarcoma cell lines, K7 and K12. Results. Northern and immunohistochemical analyses show that each cell line expressesTGF-β1 and TGF-β3 mRNA and protein. Both cell lines secrete activeTGF-β 1 and display a 30–50% reduction in growth when cultured in the presence of a TGF-β blocking antibody. Expression of TGF-β receptors TβRI, TβRII and TβRIII is demonstrated by affinity labeling with 125 -TGF-β 1, and the intermediates, Smads 2, 3 and 4, are uniformly expressed. Smads 2 and 3 are phosphorylated in response toTGF-β , while pRb phosphorylation in each osteosarcoma cell line is not affected by either exogenousTGF-β or TGF-β antibody. Conclusions. The data implicate events downstream of Smad activation, including impaired regulation of pRb, in the lack of a growth inhibitory response toTGF-β , and indicate that this murine model of osteosarcoma is valid for investigating the roles of autocrineTGF-β in vivo. PMID:18521287

  16. Temporal Control of Transforming Growth Factor (TGF) - Betal Expression on Mammary Cell Multistep Transformation

    DTIC Science & Technology

    1999-10-01

    activation of the Ras pathway, acting via MAP kinases, causes phosphorylation of Smad2 and Smad3 at specific Erk consensus sites in the linker region...Ras, acting via Erk MAP kinases, causes phosphorylation at sites in the linker region of Smad2 and Smad3 which, in turn, inhibit Smad accumulation in...addition to Smad2 and Smad4, Smad3 is an- rived from human colon carcinomas (28, 31). other member of the SMAD family of proteins The discrepancy

  17. Lovastatin, a cholesterol biosynthesis inhibitor, inhibits the growth of human H-ras oncogene transformed cells in nude mice.

    PubMed

    Sebti, S M; Tkalcevic, G T; Jani, J P

    1991-05-01

    Post-translational modification of oncogenic p21ras proteins with farnesyl, a lipid intermediate in cholesterol biosynthesis, is required for p21ras membrane association and for the ability of p21ras to transform cultured cells. We have tested the ability of lovastatin, a specific inhibitor of cholesterol biosynthesis, to inhibit the growth of ras oncogene-transformed cells in vivo. Balb/c mouse 3T3 cells, transfected with H-ras oncogene from human EJ bladder carcinoma, were highly tumorigenic in nude mice. Immunoprecipitation studies with transformed EJ cells showed that lovastatin (1-100 microM) inhibited p21ras membrane association in a concentration-dependent manner and that a 10 microM concentration reduced the amount of p21ras bound to the membrane by 50%. Lovastatin also inhibited EJ cell growth in a concentration range that closely paralleled that required for inhibition of p21ras membrane association. Treatment of nude mice bearing subcutaneous (s.c.) EJ tumors with lovastatin (50 mg/kg) significantly inhibited the abilities of these tumors to grow as early as four days and, by day 12, the lovastatin treated group of animals had tumors with an average size that was 3-fold smaller than those in the saline treated group. Western blotting studies showed that lovastatin (50 mg/kg) was also able to inhibit p21ras membrane association in EJ tumors implanted s.c. in nude mice. These results demonstrate that lovastatin, an inhibitor of cholesterol biosynthesis, inhibited in vivo tumor growth of H-ras oncogene transformed cells. The results also suggest that inhibition of p21ras membrane association, an essential step in ras oncogene neoplastic transformation, is one mechanism by which lovastatin may express its antitumor activity.

  18. Immune Cells, if Rendered Insensitive to Transforming Growth Factorbeta, Can Cure Prostate Cancer

    DTIC Science & Technology

    2007-02-01

    insensitive bone marrow transplants have met with the same fate by developing autoimmune syndrome , although these animals were able to eliminate challenged......Rendered Insensitive to Transforming Growth Factor-beta, Can 5a. CONTRACT NUMBER Cure Prostate Cancer 5b. GRANT NUMBER W81XWH-04-1-0166 5c. PROGRAM

  19. Hepatic stem cells and transforming growth factor β in hepatocellular carcinoma

    PubMed Central

    Majumdar, Avijit; Curley, Steven A.; Wu, Xifeng; Brown, Powel; Hwang, Jessica P.; Shetty, Kirti; Yao, Zhi-Xing; He, Aiwu Ruth; Li, Shulin; Katz, Lior; Farci, Patrizia; Mishra, Lopa

    2013-01-01

    Hepatocellular carcinoma (HCC) is one of the most common and lethal cancers worldwide. It arises from modulation of multiple genes by mutations, epigenetic regulation, noncoding RNAs and translational modifications of encoded proteins. Although >40% of HCCs are clonal and thought to arise from cancer stem cells (CSCs), the precise identification and mechanisms of CSC formation remain poorly understood. A functional role of transforming growth factor (TGF)-β signalling in liver and intestinal stem cell niches has been demonstrated through mouse genetics. These studies demonstrate that loss of TGF-β signalling yields a phenotype similar to a human CSC disorder, Beckwith–Wiedemann syndrome. Insights into this powerful pathway will be vital for developing new therapeutics in cancer. Current clinical approaches are aimed at establishing novel cancer drugs that target activated pathways when the TGF-β tumour suppressor pathway is lost, and TGF-β itself could potentially be targeted in metastases. Studies delineating key functional pathways in HCC and CSC formation could be important in preventing this disease and could lead to simple treatment strategies; for example, use of vitamin D might be effective when the TGF-β pathway is lost or when wnt signalling is activated. PMID:22710573

  20. The isolation and characterization of growth regulatory factors produced by a herpes simplex virus Type 2 transformed mouse tumor cell line, H238

    SciTech Connect

    Stagg, R.B.

    1988-01-01

    This study was performed in an attempt to associate HSV-2-transformation with specific growth factors in order to develop a testable model for HSV-2-transformation. We report here the isolation and characterization of four growth regulatory factors produced by H238, an HSV-2-transformed mouse tumor cell line. These factors were separated from the H238-CM by heparin-sepharose affinity chromatography into three peaks of mitogenic activity and a fourth containing inhibitory activity for splenocytes. The three peaks of mitogenic activity have been identified based on physiochemical characteristics: the first supported the anchorage-independent growth of EGF treated NRK-c-49 cells and resembles transforming growth factor-{beta} (TGF-{beta}); the second bound to lectin-coated sepharose beads and was sensitive to trypsin, neuroaminidase, and the reducing agent dithiothreitol (DTT) and, resembled a platelet-derived growth factor (PDGF)-like factor; and the third displaced ({sup 125}I)-labeled basic fibroblast growth factor (bFGF) in a dose-dependent fashion when tested with a radioimmune assay. The fourth peak was inhibitory for a variety of splenocyte function assays. A model for the interaction of these factors in vivo is presented with an emphasis on testability.

  1. Effects of ethanol on transforming growth factor Β1-dependent and -independent mechanisms of neural stem cell apoptosis.

    PubMed

    Hicks, Steven D; Miller, Michael W

    2011-06-01

    Stem cell vitality is critical for the growth of the developing brain. Growth factors can define the survival of neural stem cells (NSCs) and ethanol can affect growth factor-mediated activities. The present study tested two hypotheses: (a) ethanol causes the apoptotic death of NSCs and (b) this effect is influenced by the ambient growth factor. Monolayer cultures of non-immortalized NS-5 cells were exposed to fibroblast growth factor (FGF) 2 or transforming growth factor (TGF) β1 in the absence or presence of ethanol for 48 h. Ethanol killed NSCs as measured by increases in the numbers of ethidium bromide+ and annexin V+ cells and decreases in the number of calcein AM+ (viable) cells. These toxic effects were promoted by TGFβ1. A quantitative polymerase chain reaction array of apoptosis-related mRNAs revealed an ethanol-induced increase (≥2-fold change; p<0.05) in transcripts involved in Fas ligand (FasL) and tumor necrosis factor (TNF) signaling. These effects, particularly the FasL pathway, were potentiated by TGFβ1. Immunocytochemical analyses of NS-5 cells showed that transcriptional alterations translated into consistent up-regulation of protein expression. Experiments with the neocortical proliferative zones harvested from fetal mice exposed to ethanol showed that ethanol activated similar molecular systems in vivo. Thus, ethanol induces NSC death through two distinct molecular mechanisms, one is initiated by TGFβ1 (FasL) and another (through TNF) which is TGFβ1-independent.

  2. 14-3-3 sigma and 14-3-3 zeta plays an opposite role in cell growth inhibition mediated by transforming growth factor-beta 1.

    PubMed

    Hong, Hye-Young; Jeon, Woo-Kwang; Bae, Eun-Jin; Kim, Shin-Tae; Lee, Ho-Jae; Kim, Seong-Jin; Kim, Byung-Chul

    2010-03-01

    The expression of 14-3-3 proteins is dysregulated in various types of cancer. This study was undertaken to investigate the effects of 14-3-3 zeta and 14-3-3 sigma on cell growth inhibition mediated by transforming growth factor-beta 1 (TGF-beta1). Mouse mammary epithelial cells (Eph4) that are transformed with oncogenic c-H-Ras (EpRas) and no longer sensitive to TGF-beta1-mediated growth inhibition displayed increased expression of 14-3-3 zeta and decreased expression of 14-3-3 sigma compared with parental Eph4 cells. Using small interfering RNA-mediated knockdown and overexpression of 14-3-3 sigma or 14-3-3 zeta, we showed that 14-3-3 sigma is required for TGF-beta1-mediated growth inhibition whereas 14-3-3 zeta negatively modulates this growth inhibitory response. Notably, overexpression of 14-3-3 zeta increased the level of Smad3 protein that is phosphorylated at linker regions and cannot mediate the TGF-beta1 growth inhibitory response. Consistent with this finding, mutation of the 14-3-3 zeta phosphorylation sites in Smad3 markedly reduced the 14-3-3 zeta-mediated inhibition of TGF-beta1-induced p15 promoter-reporter activity and cell cycle arrest, suggesting that these residues are critical targets of 14-3-3 zeta in the suppression of TGF-beta1-mediated growth. Taken together, our findings indicate that dysregulation of 14-3-3 sigma or 14-3-3 zeta contributes to TGF-beta1 resistance in cancer cells.

  3. Yorkie and Scalloped: partners in growth activation.

    PubMed

    Bandura, Jennifer L; Edgar, Bruce A

    2008-03-01

    The Hippo (Hpo) signaling pathway limits organ growth in organisms from Drosophila to mammals by suppressing the activity of the transcriptional coactivator Yorkie (Yki)/YAP. The TEAD/TEF factor Scalloped (Sd) has been identified as the first known transcription factor to partner with Yki as a downstream target of Hpo signaling.

  4. Regulation of myostatin activity and muscle growth.

    PubMed

    Lee, S J; McPherron, A C

    2001-07-31

    Myostatin is a transforming growth factor-beta family member that acts as a negative regulator of skeletal muscle mass. To identify possible myostatin inhibitors that may have applications for promoting muscle growth, we investigated the regulation of myostatin signaling. Myostatin protein purified from mammalian cells consisted of a noncovalently held complex of the N-terminal propeptide and a disulfide-linked dimer of C-terminal fragments. The purified C-terminal myostatin dimer was capable of binding the activin type II receptors, Act RIIB and, to a lesser extent, Act RIIA. Binding of myostatin to Act RIIB could be inhibited by the activin-binding protein follistatin and, at higher concentrations, by the myostatin propeptide. To determine the functional significance of these interactions in vivo, we generated transgenic mice expressing high levels of the propeptide, follistatin, or a dominant-negative form of Act RIIB by using a skeletal muscle-specific promoter. Independent transgenic mouse lines for each construct exhibited dramatic increases in muscle mass comparable to those seen in myostatin knockout mice. Our findings suggest that the propeptide, follistatin, or other molecules that block signaling through this pathway may be useful agents for enhancing muscle growth for both human therapeutic and agricultural applications.

  5. Plant growth-promoting hormones activate mammalian guanylate cyclase activity.

    PubMed

    Vesely, D L; Hudson, J L; Pipkin, J L; Pack, L D; Meiners, S E

    1985-05-01

    In vivo injections of plant growth-promoting hormones increase the growth of animals as well as plants. Plant growth-promoting hormones and positive plant growth regulators are known to increase RNA and protein synthesis. Since cyclic GMP also increases RNA and protein synthesis, the object of the present investigation was to determine whether physiological levels of plant growth-promoting hormones and positive plant growth regulators have part of their mechanism(s) of action through stimulation of the guanylate cyclase (EC 4.6.1.2)-cyclic GMP system. Representatives of the three classes of growth-promoting hormones were investigated. Thus, auxins (indole-3-acetic acid, indole-3-butyric acid, beta-naphthoxyacetic acid, and 2,4,5-trichlorophenoxy acetic acid), gibberellins (gibberellic acid), and cytokinins [N6-benzyl adenine, kinetin (6-furfuryl aminopurine), and beta-(2-furyl) acrylic acid] all increased rat lung, small intestine, liver, and renal cortex guanylate cyclase activity 2- to 4-fold at the 1 microM concentration. Dose response curves revealed that maximal stimulation of guanylate cyclase by these plant growth regulators was at 1 microM; there was no augmented cyclase activity at 1 nM. The guanylate cyclase cationic cofactor manganese was not essential for augmentation of guanylate cyclase by these plant growth-promoting regulators. The antioxidant butylated hydroxytoluene did not block the enhancement of guanylate cyclase by these plant growth-promoting factors. These data suggest that guanylate cyclase may play a role in the mechanism of action of plant growth-promoting hormones and even of positive plant regulators at the cellular level.

  6. CD43 promotes cells transformation by preventing merlin-mediated contact inhibition of growth.

    PubMed

    Camacho-Concha, Nohemi; Olivos-Ortiz, Amiel; Nuñez-Rivera, Alfredo; Pedroza-Saavedra, Adolfo; Gutierrez-Xicotencatl, Lourdes; Rosenstein, Yvonne; Pedraza-Alva, Gustavo

    2013-01-01

    In normal tissues, strict control of tissue size is achieved by regulating cell numbers. The mechanism that controls total cell number is known as contact inhibition of growth and it depends on the NF2/Merlin pathway. Negative regulation of this pathway by deleterious mutations or by oncogenes results in cell transformation and tumor progression. Here we provide evidence that the CD43 sialomucin cooperates with oncogenic signals to promote cell transformation by abrogating the contact inhibition of growth through a molecular mechanism that involves AKT-dependent Merlin phosphorylation and degradation. Accordingly, inhibition of endogenous CD43 expression by RNA interference in lung, cervix and colon human cancer cells impaired tumor growth in vivo. These data underscore a previously unidentified role for CD43 in non-hematopoietic tumor progression.

  7. CD43 Promotes Cells Transformation by Preventing Merlin-Mediated Contact Inhibition of Growth

    PubMed Central

    Camacho-Concha, Nohemi; Olivos-Ortiz, Amiel; Nuñez-Rivera, Alfredo; Pedroza-Saavedra, Adolfo; Gutierrez-Xicotencatl, Lourdes; Rosenstein, Yvonne; Pedraza-Alva, Gustavo

    2013-01-01

    In normal tissues, strict control of tissue size is achieved by regulating cell numbers. The mechanism that controls total cell number is known as contact inhibition of growth and it depends on the NF2/Merlin pathway. Negative regulation of this pathway by deleterious mutations or by oncogenes results in cell transformation and tumor progression. Here we provide evidence that the CD43 sialomucin cooperates with oncogenic signals to promote cell transformation by abrogating the contact inhibition of growth through a molecular mechanism that involves AKT-dependent Merlin phosphorylation and degradation. Accordingly, inhibition of endogenous CD43 expression by RNA interference in lung, cervix and colon human cancer cells impaired tumor growth in vivo. These data underscore a previously unidentified role for CD43 in non-hematopoietic tumor progression. PMID:24260485

  8. Transforming growth factor beta-independent shuttling of Smad4 between the cytoplasm and nucleus.

    PubMed

    Pierreux, C E; Nicolás, F J; Hill, C S

    2000-12-01

    Smad4 plays a pivotal role in all transforming growth factor beta (TGF-beta) signaling pathways. Here we describe six widely expressed alternatively spliced variants of human Smad4 with deletions of different exons in the linker, the region of Smad4 that separates the two well-conserved MH1 and MH2 domains. All these Smad4 variants form complexes with activated Smad2 and Smad3 and are incorporated into DNA-binding complexes with the transcription factor Fast-1, regardless of the amount of linker they contain. However, sequences encoded by exons 5 to 7 in the linker are essential for transcriptional activation. Most importantly, our observation that different Smad4 isoforms have different subcellular localizations has led us to the identification of a functional CRM1-dependent nuclear export signal in the Smad4 linker and a constitutively active nuclear localization signal in the N-terminal MH1 domain. In the absence of TGF-beta signaling, we conclude that Smad4 is rapidly and continuously shuttling between the nucleus and the cytoplasm, the distribution of Smad4 between the nucleus and the cytoplasm being dictated by the relative strengths of the nuclear import and export signals. We demonstrate that inhibition of CRM1-mediated nuclear export by treatment of cells with leptomycin B results in endogenous Smad4 accumulating very rapidly in the nucleus. Endogenous Smad2 and Smad3 are completely unaffected by leptomycin B treatment, indicating that the nucleocytoplasmic shuttling is specific for Smad4. We propose that, upon TGF-beta signaling, complex formation between Smad4 and activated Smad2 or -3 leads to nuclear accumulation of Smad4 through inhibition of its nuclear export. We demonstrate that after prolonged TGF-beta signaling Smad2 becomes dephosphorylated and Smad2 and Smad4 accumulate back in the cytoplasm.

  9. Modulation of transforming growth factor beta receptor levels on microvascular endothelial cells during in vitro angiogenesis.

    PubMed Central

    Sankar, S; Mahooti-Brooks, N; Bensen, L; McCarthy, T L; Centrella, M; Madri, J A

    1996-01-01

    Microvascular endothelial cells (RFCs) cultured in two-dimensional (2D) cultures proliferate rapidly and exhibit an undifferentiated phenotype. Addition of transforming growth factor beta1 (TGFbeta1) increases fibronectin expression and inhibits proliferation. RFCs cultured in three-dimensional (3D) type I collagen gels proliferate slowly and are refractory to the anti-proliferative effects of TGF beta1. TGF beta1 promotes tube formation in 3D cultures. TGF beta1 increases fibronectin expression and urokinase plasminogen activator (uPA) activity and plasminogen activator inhibitor-1 (PAI-1) levels in 3D cultures. Since the TGF beta type I and II receptors have been reported to regulate different activities induced by TGF beta1, we compared the TGF beta receptor profiles on cells in 2D and 3D cultures. RFCs in 3D cultures exhibited a significant loss of cell surface type II receptor compared with cells in 2D cultures. The inhibitory effect of TGF beta1 on proliferation is suppressed in transfected 2D cultures expressing a truncated form of the type II receptor, while its stimulatory effect on fibronectin production is reduced in both 2D and 3D transfected cultures expressing a truncated form of the type I receptor. These data suggest that the type II receptor mediates the antiproliferative effect of TGF beta1 while the type I receptor mediates the matrix response of RFCs to TGF beta1 and demonstrate that changes in the matrix environment can modulate the surface expression of TGF beta receptors, altering the responsiveness of RFCs to TGF beta1. PMID:8617876

  10. Transcriptional Regulation of Human Transforming Growth Factor-α in Astrocytes.

    PubMed

    Karki, Pratap; Johnson, James; Son, Deok-Soo; Aschner, Michael; Lee, Eunsook

    2017-03-01

    Transforming growth factor-alpha (TGF-α) is known to play multifunctional roles in the central nervous system (CNS), including the provision of neurotropic properties that protect neurons against various neurotoxic insults. Previously, we reported that TGF-α mediates estrogen-induced enhancement of glutamate transporter GLT-1 function in astrocytes. However, the regulatory mechanism of TGF-α at the transcriptional level remains to be established. Our findings revealed that the human TGF-α promoter contains consensus sites for several transcription factors, such as NF-κB and yin yang 1 (YY1). NF-κB served as a positive regulator of TGF-α promoter activity, corroborated by observations that overexpression of NF-κB p65 increased, while mutation in the NF-κB binding sites in the TGF-α promoter reduced the promoter activity in rat primary astrocytes. Pharmacological inhibition of NF-κB with pyrrolidine dithiocarbamate (PDTC; 50 μM) or quinazoline (QNZ; 10 μM) also abolished TGF-α promoter activity, and NF-κB directly bound to its consensus site in the TGF-α promoter as evidenced by electrophoretic mobility shift assay (EMSA). Dexamethasone (DX) increased TGF-α promoter activity by activation of NF-κB. Treatment of astrocytes with 100 nM of DX for 24 h activated its glucocorticoid receptor and signaling proteins, including MAPK, PI3K/Akt, and PKA, via non-genomic pathways, to enhance TGF-α promoter activity and expression. YY1 served as a critical negative regulator of the TGF-α promoter as overexpression of YY1 decreased, while mutation of YY1 binding site in the promoter increased TGF-α promoter activity. Treatment for 3 h with 250 μM of manganese (Mn), an environmental neurotoxin, decreased astrocytic TGF-α expression by activation of YY1. Taken together, our results suggest that NF-κB is a critical positive regulator, whereas YY1 is a negative regulator of the TGF-α promoter. These findings identify potential molecular targets for

  11. New active series of growth hormone secretagogues.

    PubMed

    Guerlavais, Vincent; Boeglin, Damien; Mousseaux, Delphine; Oiry, Catherine; Heitz, Annie; Deghenghi, Romano; Locatelli, Vittorio; Torsello, Antonio; Ghé, Corrado; Catapano, Filomena; Muccioli, Giampiero; Galleyrand, Jean-Claude; Fehrentz, Jean-Alain; Martinez, Jean

    2003-03-27

    New growth hormone secretagogue (GHS) analogues were synthesized and evaluated for growth hormone releasing activity. This series derived from EP-51389 is based on a gem-diamino structure. Compounds that exhibited higher in vivo GH-releasing potency than hexarelin in rat (subcutaneous administration) were then tested per os in beagle dogs and for their binding affinity to human pituitary GHS receptors and to hGHS-R 1a. Compound 7 (JMV 1843, H-Aib-(d)-Trp-(d)-gTrp-formyl) showed high potency in these tests and was selected for clinical studies.(1)

  12. Solution growth of spherulitic rod and platelet calcium phosphate assemblies through polymer-assisted mesoscopic transformations.

    PubMed

    Kosma, Vassiliki A; Beltsios, Konstantinos G

    2013-05-01

    Solution growth of apatite its precursors in the presence of urea commercial gelatin is found to lead, under appropriate conditions, to a rich spectrum of morphologies, among them high aspect ratio needles in uniform sturdy spherulitic assemblies resulting from a herein documented morphological 'Chrysalis Transformation'; the latter transformation involves the growth of parallel arrays of high aspect ratio needles within micron-scale tablets the formation of a radial needle arrangement upon disruption of tablet wrapping. A different level of gelatin leads to the formation of sturdy platelet-based spherulites through another morphological transformation. We also probe the role of four simple synthetic water-soluble polymers; we find that three of them (poly(vinyl alcohol), polyvinylpyrrolidone and polyacrylamide)) also affect substantially the assembly habits of apatite; the effect is similar to that of gelatin but the attained control is less perfect/complete. The case of poly(vinyl alcohol) provides, through variation of the degree of hydrolysis, insights as regards the chain architecture features that might favor morphological transformations. Morphological transformations of particle assemblies documented herein constitute novel ways of generating dense quasi-isotropic reinforcements with high aspect ratio ceramic particles; it becomes possible to tailor calcium phosphate phases at the structural level of crystal assembly.

  13. TRANSFORMATION

    SciTech Connect

    LACKS,S.A.

    2003-10-09

    Transformation, which alters the genetic makeup of an individual, is a concept that intrigues the human imagination. In Streptococcus pneumoniae such transformation was first demonstrated. Perhaps our fascination with genetics derived from our ancestors observing their own progeny, with its retention and assortment of parental traits, but such interest must have been accelerated after the dawn of agriculture. It was in pea plants that Gregor Mendel in the late 1800s examined inherited traits and found them to be determined by physical elements, or genes, passed from parents to progeny. In our day, the material basis of these genetic determinants was revealed to be DNA by the lowly bacteria, in particular, the pneumococcus. For this species, transformation by free DNA is a sexual process that enables cells to sport new combinations of genes and traits. Genetic transformation of the type found in S. pneumoniae occurs naturally in many species of bacteria (70), but, initially only a few other transformable species were found, namely, Haemophilus influenzae, Neisseria meningitides, Neisseria gonorrheae, and Bacillus subtilis (96). Natural transformation, which requires a set of genes evolved for the purpose, contrasts with artificial transformation, which is accomplished by shocking cells either electrically, as in electroporation, or by ionic and temperature shifts. Although such artificial treatments can introduce very small amounts of DNA into virtually any type of cell, the amounts introduced by natural transformation are a million-fold greater, and S. pneumoniae can take up as much as 10% of its cellular DNA content (40).

  14. Handling Arabidopsis plants: growth, preservation of seeds, transformation, and genetic crosses.

    PubMed

    Rivero, Luz; Scholl, Randy; Holomuzki, Nicholas; Crist, Deborah; Grotewold, Erich; Brkljacic, Jelena

    2014-01-01

    Growing healthy plants is essential for the advancement of Arabidopsis thaliana (Arabidopsis) research. Over the last 20 years, the Arabidopsis Biological Resource Center (ABRC) has collected and developed a series of best-practice protocols, some of which are presented in this chapter. Arabidopsis can be grown in a variety of locations, growth media, and environmental conditions. Most laboratory accessions and their mutant or transgenic derivatives flower after 4-5 weeks and set seeds after 7-8 weeks, under standard growth conditions (soil, long day, 23 ºC). Some mutant genotypes, natural accessions, and Arabidopsis relatives require strict control of growth conditions best provided by growth rooms, chambers, or incubators. Other lines can be grown in less-controlled greenhouse settings. Although the majority of lines can be grown in soil, certain experimental purposes require utilization of sterile solid or liquid growth media. These include the selection of primary transformants, identification of homozygous lethal individuals in a segregating population, or bulking of a large amount of plant material. The importance of controlling, observing, and recording growth conditions is emphasized and appropriate equipment required to perform monitoring of these conditions is listed. Proper conditions for seed harvesting and preservation, as well as seed quality control, are also described. Plant transformation and genetic crosses, two of the methods that revolutionized Arabidopsis genetics, are introduced as well.

  15. Correlation of fibrosis and transforming growth factor-beta type 2 levels in the eye.

    PubMed

    Connor, T B; Roberts, A B; Sporn, M B; Danielpour, D; Dart, L L; Michels, R G; de Bustros, S; Enger, C; Kato, H; Lansing, M

    1989-05-01

    Approximately 1 out of every 10 eyes undergoing surgery for retinal detachment develops excessive intraocular fibrosis that can lead to traction retinal detachment and ultimate blindness. This disease process has been termed proliferative vitreoretinopathy (PVR). The ability to monitor and grade this fibrotic response accurately within the eye as well as the ability to aspirate vitreous cavity fluid bathing the fibrotic tissue makes this an ideal setting in which to investigate the development of fibrosis. Although laboratory studies have recently shown that transforming growth factor-beta (TGF-beta) can enhance fibrosis, little clinical evidence is yet available correlating the level of this or other growth factors with the degree of fibrosis in a clinical setting. We have found that vitreous aspirates from eyes with intraocular fibrosis associated with PVR have more than three times the amount of TGF-beta (1,200 +/- 300 pM [SEM]) found in eyes with uncomplicated retinal detachments without intraocular fibrosis (360 +/- 91 pM [SEM]). Using an in vitro assay, 84-100% of the TGF-beta activity could be blocked with specific antibodies against TGF-beta 2, whereas only 10-21% could be blocked by specific antibodies against TGF-beta 1. TGF-beta 1 was used in an animal model of traction retinal detachment. Since beta 1 and beta 2 have essentially identical biologic effects and only human beta 1 was available in quantities required, beta 1 was chosen for these in vivo studies. The injection of TGF-beta1 plus fibronectin (FN) but not TGF-beta1 alone into the vitreous cavity of rabbits resulted in the increased formation of intraocular fibrosis and traction retinal detachments as compared to control eyes. In previous studies, intravitreal FN levels were also found to be elevated in eyes with intraocular fibrosis.

  16. Impairment of Transforming Growth Factor β Signaling in Caveolin-1-deficient Hepatocytes

    PubMed Central

    Mayoral, Rafael; Valverde, Ángela M.; Llorente Izquierdo, Cristina; González-Rodríguez, Águeda; Boscá, Lisardo; Martín-Sanz, Paloma

    2010-01-01

    Caveolin-1 (Cav-1) is the main structural protein of caveolae and plays an important role in various cellular processes such as vesicular transport, cholesterol homeostasis, and signal transduction pathways. The expression and functional role of Cav-1 have been reported in liver and in hepatocyte cell lines, in human cirrhotic liver, and in hepatocellular carcinomas. Previous studies demonstrated that Cav-1 was dispensable for liver regeneration, because Cav-1−/− animals survived and fully regenerated liver function and size after partial hepatectomy. In this study, we have investigated the mechanisms by which the lack of Cav-1 accelerates liver regeneration after partial hepatectomy. The data show that transforming growth factor β (TGF-β) signaling is impaired in regenerating liver of Cav-1−/− mice and in hepatocytes derived from these animals. TGF-β receptors I and II do not colocalize in the same membrane fraction in the hepatocytes derived from Cav-1−/− mice, as Smad2/3 signaling decreased in the absence of Cav-1 at the time that the transcriptional corepressor SnoN accumulates. Accordingly, the expression of TGF-β target genes, such as plasminogen activator inhibitor-1, is decreased due to the presence of the high levels of SnoN. Moreover, hepatocyte growth factor inhibited TGF-β signaling in the absence of Cav-1 by increasing SnoN expression. Taken together, these data might help to unravel why Cav-1-deficient mice exhibit an accelerated liver regeneration after partial hepatectomy and add new insights on the molecular mechanisms controlling the initial commitment to hepatocyte proliferation. PMID:19966340

  17. Transforming Growth Factors β Coordinate Cartilage and Tendon Differentiation in the Developing Limb Mesenchyme*

    PubMed Central

    Lorda-Diez, Carlos I.; Montero, Juan A.; Martinez-Cue, Carmen; Garcia-Porrero, Juan A.; Hurle, Juan M.

    2009-01-01

    Transforming growth factor β (TGFβ) signaling has an increasing interest in regenerative medicine as a potential tool to repair cartilages, however the chondrogenic effect of this pathway in developing systems is controversial. Here we have analyzed the function of TGFβ signaling in the differentiation of the developing limb mesoderm in vivo and in high density micromass cultures. In these systems highest signaling activity corresponded with cells at stages preceding overt chondrocyte differentiation. Interestingly treatments with TGFβs shifted the differentiation outcome of the cultures from chondrogenesis to fibrogenesis. This phenotypic reprogramming involved down-regulation of Sox9 and Aggrecan and up-regulation of Scleraxis, and Tenomodulin through the Smad pathway. We further show that TGFβ signaling up-regulates Sox9 in the in vivo experimental model system in which TGFβ treatments induce ectopic chondrogenesis. Looking for clues explaining the dual role of TGFβ signaling, we found that TGFβs appear to be direct inducers of the chondrogenic gene Sox9, but the existence of transcriptional repressors of TGFβ signaling modulates this role. We identified TGF-interacting factor Tgif1 and SKI-like oncogene SnoN as potential candidates for this inhibitory function. Tgif1 gene regulation by TGFβ signaling correlated with the differential chondrogenic and fibrogenic effects of this pathway, and its expression pattern in the limb marks the developing tendons. In functional experiments we found that Tgif1 reproduces the profibrogenic effect of TGFβ treatments. PMID:19717568

  18. Recruitment and development of the follicle; the roles of the transforming growth factor-beta superfamily.

    PubMed

    Findlay, J K; Drummond, A E; Dyson, M L; Baillie, A J; Robertson, D M; Ethier, J-F

    2002-05-31

    Peripheral endocrine hormones and local paracrine and autocrine factors contribute, in a coordinated fashion, to the processes of recruitment, development or atresia, selection and ovulation of follicles. Among the local ovarian factors, there is growing evidence from genetic and experimental data that many members of the transforming growth factor (TGFbeta) superfamily have a biological role to play in folliculogenesis. These members include activin, inhibin, TGFbeta, BMP, GDF9 and perhaps MIS. In this review, we discuss the potential roles of the TGFbeta superfamily members, in particular activin, during folliculogenesis. Since the actions of these factors are determined by ligand availability, receptor expression and modulation of their signal transduction pathways, we also collate information on the expression of their signalling components in the follicle. We conclude that the TGFbeta superfamily signalling pathways, in particular activin's pathway, reside in the ovary. Furthermore, follistatin and beta-glycan-components of the accessory binding protein system that modifies activin action-are also present in follicles. In the post-natal rat ovary, the changes in receptor/Smad expression coincide with granulosa cell proliferation and antrum formation. We hypothesise that these pathway components are expressed in a temporal and cell-specific manner to meet the changing demands of cells during follicular development. The analysis of the components of the signal transduction pathways of the TGFbeta family members in populations of defined follicles and the identification of activated pathways in individually stimulated follicles should help clarify the roles of the TGFbeta members in folliculogenesis.

  19. Transforming growth factor-β2 is sequestered in preterm human milk by chondroitin sulfate proteoglycans.

    PubMed

    Namachivayam, Kopperuncholan; Coffing, Hayley P; Sankaranarayanan, Nehru Viji; Jin, Yingzi; MohanKumar, Krishnan; Frost, Brandy L; Blanco, Cynthia L; Patel, Aloka L; Meier, Paula P; Garzon, Steven A; Desai, Umesh R; Maheshwari, Akhil

    2015-08-01

    Human milk contains biologically important amounts of transforming growth factor-β2 isoform (TGF-β2), which is presumed to protect against inflammatory gut mucosal injury in the neonate. In preclinical models, enterally administered TGF-β2 can protect against experimental necrotizing enterocolitis, an inflammatory bowel necrosis of premature infants. In this study, we investigated whether TGF-β bioactivity in human preterm milk could be enhanced for therapeutic purposes by adding recombinant TGF-β2 (rTGF-β2) to milk prior to feeding. Milk-borne TGF-β bioactivity was measured by established luciferase reporter assays. Molecular interactions of TGF-β2 were investigated by nondenaturing gel electrophoresis and immunoblots, computational molecular modeling, and affinity capillary electrophoresis. Addition of rTGF-β2 (20-40 nM) to human preterm milk samples failed to increase TGF-β bioactivity in milk. Milk-borne TGF-β2 was bound to chondroitin sulfate (CS) containing proteoglycan(s) such as biglycan, which are expressed in high concentrations in milk. Chondroitinase treatment of milk increased the bioactivity of both endogenous and rTGF-β2, and consequently, enhanced the ability of preterm milk to suppress LPS-induced NF-κB activation in macrophages. These findings provide a mechanism for the normally low bioavailability of milk-borne TGF-β2 and identify chondroitinase digestion of milk as a potential therapeutic strategy to enhance the anti-inflammatory effects of preterm milk.

  20. Regulation of the transforming growth factor β pathway by reversible ubiquitylation

    PubMed Central

    Al-Salihi, Mazin A.; Herhaus, Lina; Sapkota, Gopal P.

    2012-01-01

    The transforming growth factor β (TGFβ) signalling pathway plays a central role during embryonic development and in adult tissue homeostasis. It regulates gene transcription through a signalling cascade from cell surface receptors to intracellular SMAD transcription factors and their nuclear cofactors. The extent, duration and potency of signalling in response to TGFβ cytokines are intricately regulated by complex biochemical processes. The corruption of these regulatory processes results in aberrant TGFβ signalling and leads to numerous human diseases, including cancer. Reversible ubiquitylation of pathway components is a key regulatory process that plays a critical role in ensuring a balanced response to TGFβ signals. Many studies have investigated the mechanisms by which various E3 ubiquitin ligases regulate the turnover and activity of TGFβ pathway components by ubiquitylation. Moreover, recent studies have shed new light into their regulation by deubiquitylating enzymes. In this report, we provide an overview of current understanding of the regulation of TGFβ signalling by E3 ubiquitin ligases and deubiquitylases. PMID:22724073

  1. Regulation of Transforming Growth Factor-β1–driven Lung Fibrosis by Galectin-3

    PubMed Central

    MacKinnon, Alison C.; Gibbons, Michael A.; Farnworth, Sarah L.; Leffler, Hakon; Nilsson, Ulf J.; Delaine, Tamara; Simpson, A. John; Forbes, Stuart J.; Hirani, Nik; Gauldie, Jack

    2012-01-01

    Rationale: Idiopathic pulmonary fibrosis (IPF) is a chronic dysregulated response to alveolar epithelial injury with differentiation of epithelial cells and fibroblasts into matrix-secreting myofibroblasts resulting in lung scaring. The prognosis is poor and there are no effective therapies or reliable biomarkers. Galectin-3 is a β-galactoside binding lectin that is highly expressed in fibrotic tissue of diverse etiologies. Objectives: To examine the role of galectin-3 in pulmonary fibrosis. Methods: We used genetic deletion and pharmacologic inhibition in well-characterized murine models of lung fibrosis. Further mechanistic studies were performed in vitro and on samples from patients with IPF. Measurements and Main Results: Transforming growth factor (TGF)-β and bleomycin-induced lung fibrosis was dramatically reduced in mice deficient in galectin-3, manifest by reduced TGF-β1–induced EMT and myofibroblast activation and collagen production. Galectin-3 reduced phosphorylation and nuclear translocation of β-catenin but had no effect on Smad2/3 phosphorylation. A novel inhibitor of galectin-3, TD139, blocked TGF-β–induced β-catenin activation in vitro and in vivo and attenuated the late-stage progression of lung fibrosis after bleomycin. There was increased expression of galectin-3 in the bronchoalveolar lavage fluid and serum from patients with stable IPF compared with nonspecific interstitial pneumonitis and controls, which rose sharply during an acute exacerbation suggesting that galectin-3 may be a marker of active fibrosis in IPF and that strategies that block galectin-3 may be effective in treating acute fibrotic exacerbations of IPF. Conclusions: This study identifies galectin-3 as an important regulator of lung fibrosis and provides a proof of principle for galectin-3 inhibition as a potential novel therapeutic strategy for IPF. PMID:22095546

  2. Onset and progression of pathological lesions in transforming growth factor-beta 1-deficient mice.

    PubMed Central

    Boivin, G. P.; O'Toole, B. A.; Orsmby, I. E.; Diebold, R. J.; Eis, M. J.; Doetschman, T.; Kier, A. B.

    1995-01-01

    Null-mutant (knockout) mice were obtained through disruption of the sixth exon of the endogenous transforming growth factor-beta 1 allele in murine embryonic stem cells via homologous recombination. Mice lacking transforming growth factor-beta 1 (mutants) were born grossly indistinguishable from wild-type littermates. With time, mutant mice exhibited a wasting phenotype that manifested itself in severe weight loss and dishevelled appearance (between 15 and 36 days of age). Examination of these moribund mice histologically revealed that transforming growth factor-beta 1-deficient mice exhibit a moderate to severe, multifocal, organ-dependent, mixed inflammatory cell response adversely affecting the heart, stomach, diaphragm, liver, lung, salivary gland, and pancreas. Because of the known multifunctional nature of transforming growth factor-beta 1 on the control of growth and differentiation of many different cell types, it is important to determine the degree to which the inflammatory response interacts with or masks other deficiencies that are present. To this end, we examined the extent and nature of the inflammatory lesions in different ages of neonatal knockout mice (5, 7, 10, and 14 days of age) and older moribund mice (> 15 days of age) and compared them with the histology seen in wild-type normal animals. Mild inflammatory infiltrates were first observed in 5-day mutant mice in the heart, by day 7 in the lung, salivary gland, and pancreas, and by day 14 inflammatory lesions were found in almost all organs examined. Moderate to severe inflammation was not present until the mice were 10 to 14 days old. In the older animals, there was a slight increase in the severity of the inflammatory lesions as the mice aged. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7856734

  3. Induced RAW 264.7 macrophages express soluble and particulate nitric oxide synthase: inhibition by transforming growth factor-beta.

    PubMed

    Förstermann, U; Schmidt, H H; Kohlhaas, K L; Murad, F

    1992-02-13

    RAW 264.7 macrophages induced with lipopolysaccharide and interferon-gamma expressed nitric oxide (NO) synthase. Approximately two-thirds of the total induced NO synthase activity was found in the cytosolic fraction, whereas one-third was associated with the particulate fraction. Both enzymes formed L-citrulline in addition to NO-like material. NO and L-citrulline formation by both enzymes were calcium-independent and inhibited by NG-nitro-L-arginine and NG-methyl-L-arginine. Transforming growth factor-beta 1 prevented the induction of both enzymes.

  4. Transforming growth factor-(beta)s and mammary gland involution; functional roles and implications for cancer progression.

    PubMed

    Flanders, Kathleen C; Wakefield, Lalage M

    2009-06-01

    During rodent mammary gland involution there is a dramatic increase in the expression of the transforming growth factor-beta isoform, TGF-beta3. The TGF-betas are multifunctional cytokines which play important roles in wound healing and in carcinogenesis. The responses that are activated in the remodeling of the gland during involution have many similarities with the wound healing process and have been postulated to generate a mammary stroma that provides a microenvironment favoring tumor progression. In this review we will discuss the putative role of TGF-beta during involution, as well as its effects on the mammary microenvironment and possible implications for pregnancy-associated tumorigenesis.

  5. TRANSFORMER

    DOEpatents

    Baker, W.R.

    1959-08-25

    Transformers of a type adapted for use with extreme high power vacuum tubes where current requirements may be of the order of 2,000 to 200,000 amperes are described. The transformer casing has the form of a re-entrant section being extended through an opening in one end of the cylinder to form a coaxial terminal arrangement. A toroidal multi-turn primary winding is disposed within the casing in coaxial relationship therein. In a second embodiment, means are provided for forming the casing as a multi-turn secondary. The transformer is characterized by minimized resistance heating, minimized external magnetic flux, and an economical construction.

  6. Effects of microgravity on osteoblast growth activation

    NASA Technical Reports Server (NTRS)

    Hughes-Fulford, M.; Lewis, M. L.

    1996-01-01

    Space flight is an environmental condition where astronauts can lose up to 19% of weight-bearing bone during long duration missions. We used the MC3T3-E1 osteoblast to investigate bone cell growth in microgravity (10(-6) to 10(-9)g). Osteoblasts were launched on the STS-56 shuttle flight in a quiescent state with 0.5% fetal calf serum (FCS) medium and growth activation was initiated by adding fresh medium with 10% FCS during microgravity exposure. Four days after serum activation, the cells were fixed before return to normal Earth gravity. Ground controls were treated in parallel with the flight samples in identical equipment. On landing, cell number, cell cytoskeleton, glucose utilization, and prostaglandin synthesis in flight (n = 4) and ground controls (n = 4) were examined. The flown osteoblasts grew slowly in microgravity with total cell number significantly reduced (55 +/- 6 vs 141 +/- 8 cells per microscopic field). The cytoskeleton of the flight osteoblasts had a reduced number of stress fibers and a unique abnormal morphology. Nuclei in the ground controls were large and round with punctate Hoechst staining of the DNA nucleosomes. The flight nuclei were 30% smaller than the controls (P < 0.0001) and oblong in shape, with fewer punctate areas. Due to their reduced numbers, the cells activated in microgravity used significantly less glucose than ground controls (80.2 +/- 0.7 vs 50.3 +/- 3.7 mg of glucose/dl remaining in the medium) and had reduced prostaglandin E2 (PGE2) synthesis when compared to controls (57.3 +/- 17 vs 138.3 +/- 41 pmol/ml). Cell viability was normal since, on a per-cell basis, glucose use and prostaglandin synthesis were comparable for flight and ground samples. Taken together, these data suggest that growth activation in microgravity results in reduced growth, causing reduced glucose utilization and reduced prostaglandin synthesis, with significantly altered actin cytoskeleton in osteoblasts.

  7. Early growth response 3 (Egr-3) is induced by transforming growth factor-β and regulates fibrogenic responses.

    PubMed

    Fang, Feng; Shangguan, Anna J; Kelly, Kathleen; Wei, Jun; Gruner, Katherine; Ye, Boping; Wang, Wenxia; Bhattacharyya, Swati; Hinchcliff, Monique E; Tourtellotte, Warren G; Varga, John

    2013-10-01

    Members of the early growth response (Egr) gene family of transcription factors have nonredundant biological functions. Although Egr-3 is implicated primarily in neuromuscular development and immunity, its regulation and role in tissue repair and fibrosis has not been studied. We now show that in normal skin fibroblasts, Egr-3 was potently induced by transforming growth factor-β via canonical Smad3. Moreover, transient Egr-3 overexpression was sufficient to stimulate fibrotic gene expression, whereas deletion of Egr-3 resulted in substantially attenuated transforming growth factor-β responses. Genome-wide expression profiling in fibroblasts showed that genes associated with tissue remodeling and wound healing were prominently up-regulated by Egr-3. Notably, <5% of fibroblast genes regulated by Egr-1 or Egr-2 were found to be coregulated by Egr-3, revealing substantial functional divergence among these Egr family members. In a mouse model of scleroderma, development of dermal fibrosis was accompanied by accumulation of Egr-3-positive myofibroblasts in the lesional tissue. Moreover, skin biopsy samples from patients with scleroderma showed elevated Egr-3 levels in the dermis, and Egr-3 mRNA levels correlated with the extent of skin involvement. These results provide the first evidence that Egr-3, a functionally distinct member of the Egr family with potent effects on inflammation and immunity, is up-regulated in scleroderma and is necessary and sufficient for profibrotic responses, suggesting important and distinct roles in the pathogenesis of fibrosis.

  8. Caerulomycin A Enhances Transforming Growth Factor-β (TGF-β)-Smad3 Protein Signaling by Suppressing Interferon-γ (IFN-γ)-Signal Transducer and Activator of Transcription 1 (STAT1) Protein Signaling to Expand Regulatory T Cells (Tregs)*

    PubMed Central

    Gurram, Rama Krishna; Kujur, Weshely; Maurya, Sudeep K.; Agrewala, Javed N.

    2014-01-01

    Cytokines play a very important role in the regulation of immune homeostasis. Regulatory T cells (Tregs) responsible for the generation of peripheral tolerance are under the tight regulation of the cytokine milieu. In this study, we report a novel role of a bipyridyl compound, Caerulomycin A (CaeA), in inducing the generation of Tregs. It was observed that CaeA substantially up-regulated the pool of Tregs, as evidenced by an increased frequency of CD4+ Foxp3+ cells. In addition, CaeA significantly suppressed the number of Th1 and Th17 cells, as supported by a decreased percentage of CD4+/IFN-γ+ and CD4+/IL-17+ cells, respectively. Furthermore, we established the mechanism and observed that CaeA interfered with IFN-γ-induced STAT1 signaling by augmenting SOCS1 expression. An increase in the TGF-β-mediated Smad3 activity was also noted. Furthermore, CaeA rescued Tregs from IFN-γ-induced inhibition. These results were corroborated by blocking Smad3 activity, which abolished the CaeA-facilitated generation of Tregs. In essence, our results indicate a novel role of CaeA in inducing the generation of Tregs. This finding suggests that CaeA has enough potential to be considered as a potent future drug for the treatment of autoimmunity. PMID:24811173

  9. Growth factor expression in degenerated intervertebral disc tissue. An immunohistochemical analysis of transforming growth factor beta, fibroblast growth factor and platelet-derived growth factor.

    PubMed

    Tolonen, Jukka; Grönblad, Mats; Vanharanta, Heikki; Virri, Johanna; Guyer, Richard D; Rytömaa, Tapio; Karaharju, Erkki O

    2006-05-01

    Degenerated intervertebral disc has lost its normal architecture, and there are changes both in the nuclear and annular parts of the disc. Changes in cell shape, especially in the annulus fibrosus, have been reported. During degeneration the cells become more rounded, chondrocyte-like, whereas in the normal condition annular cells are more spindle shaped. These chondrocyte-like cells, often forming clusters, affect extracellular matrix turnover. In previous studies transforming growth factor beta (TGFbeta) -1 and -2, basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF) have been highlighted in herniated intervertebral disc tissue. In the present study the same growth factors are analysed immunohistochemically in degenerated intervertebral disc tissue. Disc material was obtained from 16 discs operated for painful degenerative disc disease. Discs were classified according to the Dallas Discogram Description. Different disc regions were analysed in parallel. As normal control disc tissue material from eight organ donors was used. Polyclonal antibodies against different growth factors and TGFbeta receptor type II were used, and the immunoreaction was detected by the avidin biotin complex method. All studied degenerated discs showed immunoreactivity for TGFbeta receptor type II and bFGF. Fifteen of 16 discs were immunopositive for TGFbeta-1 and -2, respectively, and none showed immunoreaction for PDGF. Immunopositivity was located in blood vessels and in disc cells. In the nucleus pulposus the immunoreaction was located almost exclusively in chondrocyte-like disc cells, whereas in the annular region this reaction was either in chondrocyte-like disc cells, often forming clusters, or in fibroblast-like disc cells. Chondrocyte-like disc cells were especially prevalent in the posterior disrupted area. In the anterior area of the annulus fibrosus the distribution was more even between these two cell types. bFGF was expressed in the anterior annulus

  10. Emerging Roles of Transforming Growth Factor β Signaling in Diabetic Retinopathy.

    PubMed

    Wheeler, Sarah E; Lee, Nam Y

    2017-03-01

    Diabetic retinopathy (DR) is a serious complication of diabetes mellitus affecting about one third of diabetic adults. Despite its prevalence, treatment options are limited and often implemented only in the later stages of the disease. To date, the pathogenesis of DR has been extensively characterized in the context of elevated glucose, insulin, and VEGF signaling, although a growing number of other growth factors and molecules, including transforming growth factor β (TGF-β) are being recognized as important contributors and/or therapeutic targets. Here, we review the complex roles of TGF-β signaling in DR pathogenesis and progression. J. Cell. Physiol. 232: 486-489, 2017. © 2016 Wiley Periodicals, Inc.

  11. Mediation of wound-related Rous sarcoma virus tumorigenesis by TFG (transforming growth factor)-. beta

    SciTech Connect

    Sieweke, M.H.; Bissell, M.J. ); Thompson, N.L.; Sporn, M.B. )

    1990-06-29

    In Rous sarcoma virus (RSV)-infected chickens, wounding leads to tumor formation with nearly 100% frequency in tissues that would otherwise remain tumor-free. Identifying molecular mediators of this phenomenon should yield important clues to the mechanisms involved in RSV tumorigenesis. Immunohistochemical staining showed that TGF-{beta} is present locally shortly after wounding, but not in unwounded controls. In addition, subcutaneous administration of recombinant transforming growth factor {beta}1 (TGF-{beta}1) could substitute completely for wounding in tumor induction. A treatment protocol of four doses of 800 nanograms of TGF-{beta} resulted in v-src-expressing tumors with 100% frequency; four doses of only 10 nanograms still led to tumor formation in 80% of the animals. This effect was specific, as other growth factors with suggested roles in would healing did not elicit the same response. Epidermal growth factor (EGF) or TGF-{alpha} had no effect, and platelet-derived growth factor (PDGF) or insulin-like growth factor-1 (IGF-1) yielded only occasional tumors after longer latency. TGF-{beta} release during the would-healing response may thus be a critical event that creates a conducive environment for RSV tumorigenesis and may act as a cofactor for transformation in this system. 31 refs., 3 figs., 2 tabs.

  12. [Effects of nitrogen regulators on fertilizer nitrogen transformation in meadow cinnamon soil and on pakchoi growth].

    PubMed

    Sun, Zhi-Mei; Zhang, Kuo; Liu, Jian-Tao; Si, Huan-Sen; Wang, Yan-Qun

    2012-09-01

    Soil incubation test and pot experiment were conducted to investigate the effects of dicyandiamide (DCD) and its combination with nano-carbon on the transformation of fertilizers (urea and ammonium bicarbonate) nitrogen (N) in meadow cinnamon soil, a typical soil type in North China Plain, and on the growth of pakchoi (Brassica chinensis). In the first two weeks after applying urea and ammonium bicarbonate, the soil NH4+-N and NO3(-)-N contents varied greatly, but little variation was observed since then. The effects of the applied fertilizer N on the pakchoi growth and its N use efficiency differed significantly at early growth stages, but had little difference at harvesting stage. The DCD inhibited the transformation of the fertilizer N (especially ammonium bicarbonate N) into nitrate markedly, and this effect increased with increasing DCD dose. Under the conditions of our experiment, the optimal application rate of DCD was 1.0-1.5% of applied fertilize N, which could increase the pakchoi yield significantly, improve the leaf color, decrease the plant nitrate contents, and increase the fertilizer N use efficiency. The combination of DCD and nano-carbon exerted a synergistic effect on inhibiting soil ammonium oxidation, and also, promoted the pakchoi growth and N utilization at early growth stages significantly and decreased the plant nitrate level at harvesting stage.

  13. Epithelium-dependent extracellular matrix synthesis in transforming growth factor-beta 1-growth-inhibited mouse mammary gland.

    PubMed

    Silberstein, G B; Strickland, P; Coleman, S; Daniel, C W

    1990-06-01

    Exogenous transforming growth factor beta (TGF-beta 1) was shown in earlier studies to reversibly inhibit mouse mammary ductal growth. Using small plastic implants to treat regions of developing mammary glands in situ, we now report that TGF-beta 1 growth inhibition is associated with an ectopic accumulation of type I collagen messenger RNA and protein, as well as the glycosaminoglycan, chondroitin sulfate. Both macromolecules are normal components of the ductal extracellular matrix, which, under the influence of exogenous TGF-beta 1, became unusually concentrated immediately adjacent to the epithelial cells at the tip of the ductal growth points, the end buds. Stimulation of extracellular matrix was confined to aggregations of connective tissue cells around affected end buds and was not present around the TGF-beta 1 implants themselves, indicating that the matrix effect was epithelium dependent. Ectopic matrix synthesis was specific for TGF-beta 1 insofar as it was absent at ducts treated with other growth inhibitors, or at ducts undergoing normal involution in response to endogenous regulatory processes. These findings are consistent with the matrix-stimulating properties of TGF-beta 1 reported for other systems, but differ in their strict dependence upon epithelium. A possible role for endogenous TGF-beta 1 in modulating a mammary epithelium-stroma interaction is suggested.

  14. Oncogenic transformation of mesenchymal stem cells decreases Nrf2 expression favoring in vivo tumor growth and poorer survival

    PubMed Central

    2014-01-01

    Background The transcription factor Nrf2 is a key regulator of the cellular antioxidant response, and its activation by chemoprotective agents has been proposed as a potential strategy to prevent cancer. However, activating mutations in the Nrf2 pathway have been found to promote tumorigenesis in certain models. Therefore, the role of Nrf2 in cancer remains contentious. Methods We employed a well-characterized model of stepwise human mesenchymal stem cell (MSC) transformation and breast cancer cell lines to investigate oxidative stress and the role of Nrf2 during tumorigenesis. The Nrf2 pathway was studied by microarray analyses, qRT-PCR, and western-blotting. To assess the contribution of Nrf2 to transformation, we established tumor xenografts with transformed MSC expressing Nrf2 (n = 6 mice per group). Expression and survival data for Nrf2 in different cancers were obtained from GEO and TCGA databases. All statistical tests were two-sided. Results We found an accumulation of reactive oxygen species during MSC transformation that correlated with the transcriptional down-regulation of antioxidants and Nrf2-downstream genes. Nrf2 was repressed in transformed MSC and in breast cancer cells via oncogene-induced activation of the RAS/RAF/ERK pathway. Furthermore, restoration of Nrf2 function in transformed cells decreased reactive oxygen species and impaired in vivo tumor growth (P = 0.001) by mechanisms that included sensitization to apoptosis, and a decreased hypoxic/angiogenic response through HIF-1α destabilization and VEGFA repression. Microarray analyses showed down-regulation of Nrf2 in a panel of human tumors and, strikingly, low Nrf2 expression correlated with poorer survival in patients with melanoma (P = 0.0341), kidney (P = 0.0203) and prostate (P = 0.00279) cancers. Conclusions Our data indicate that oncogene-induced Nrf2 repression is an adaptive response for certain cancers to acquire a pro-oxidant state that favors cell survival and

  15. Secreted proteins induced by epidermal growth factor and transforming growth factor beta in EL2 rat fibroblasts. Role in the mitogenic response.

    PubMed

    Di Francesco, P; Favalli, C; Liboi, E

    1988-05-01

    Most growth active hormones and peptides are mitogenic only in the presence of other growth factors [e.g., Platelet Derived Growth Factor (PDGF) and Epidermal Growth Factor (EGF) in "competence-progression" fibroblast model]. We have previously described that EGF alone is able to induce the signals which appear necessary for the mitogenic stimulation of EL2 rat embryo fibroblast line. Recently, we have demonstrated that Transforming Growth Factor beta (TGF beta) slightly stimulates the mitogenic response in EL2 cells. Here, we show that in EGF-treated EL2 cells the induction of at least four inducible-secreted proteins (ISPs, range from 29,000 to 68,000 Mr) is accompanied by a marked increase in DNA synthesis. In contrast, TGF beta or different concentrations of EGF induce a slow increase of the ISPs proportional to slow induction in DNA synthesis. Our results suggest that the mitogenic response in EL2 cell line may be connected with the qualitative and quantitative induction of these secreted proteins.

  16. The role of insulin-like growth factor II in the malignant transformation of rat liver oval cells.

    PubMed

    Zhang, N; Siegel, K; Odenthal, M; Becker, R; Oesch, F; Dienes, H P; Schirmacher, P; Steinberg, P

    1997-04-01

    Oval cells are small nonparenchymal epithelial cells that first appear in the periportal areas of the liver and thereafter invade the whole parenchyma when mice or rats are exposed to a variety of chemical carcinogens. In the present study we have analyzed the expression of insulin-like growth factor II (IGF II) in the recently established oval cell line OC/CDE 22 and its malignantly transformed counterpart (the M22 cells) and the biological consequences of the constitutive expression of IGF II in oval cells. OC/CDE 22 cells do not express the above-mentioned growth factor, whereas the M22 cells do and addition of a neutralizing anti-IGF II antibody to M22 cells resulted in an almost complete proliferation stop. The presence of type 1 as well as type 2 insulin-like growth factor receptors in OC/CDE 22 and M22 cells was revealed by Northern blotting; however, only neutralizing antibodies directed against the type 1 IGF receptor were able to inhibit the proliferation of the cultured oval cells. Finally, transfection of an IGF II complementary DNA (cDNA) into OC/CDE 22 cells resulted in the release of active IGF II into the extracellular medium but not in the concomitant malignant transformation of the cells. Taken together these results show that: 1) upon transformation oval cells start producing IGF II and 2) IGF II acts on oval cells as a pure mitogen (without being per se oncogenic) via an autocrine loop involving the activation of the type 1 IGF receptor.

  17. Extended Squire's transformation and its consequences for transient growth in a confined shear flow

    NASA Astrophysics Data System (ADS)

    John Soundar Jerome, J.; Chomaz, Jean-Marc

    2014-04-01

    The classical Squire transformation is extended to the entire eigenfunction structure of both Orr-Sommerfeld and Squire modes. For arbitrary Reynolds numbers Re, this transformation allows the solution of the initial-value problem for an arbitrary three-dimensional (3D) disturbance via a two-dimensional (2D) initial-value problem at a smaller Reynolds number Re2D. Its implications for the transient growth of arbitrary 3D disturbances is studied. Using the Squire transformation, the general solution of the initial-value problem is shown to predict large-Reynolds-number scaling for the optimal gain at all optimization times t with t/Re finite or large. This result is an extension of the well-known scaling laws first obtained by Gustavsson (J. Fluid Mech., vol. 224, 1991, pp. 241-260) and Reddy & Henningson (J. Fluid Mech., vol. 252, 1993, pp. 209-238) for arbitrary \\alpha Re, where \\alpha is the streamwise wavenumber. The Squire transformation is also extended to the adjoint problem and, hence, the adjoint Orr-Sommerfeld and Squire modes. It is, thus, demonstrated that the long-time optimal growth of 3D perturbations as given by the exponential growth (or decay) of the leading eigenmode times an extra gain representing its receptivity, may be decomposed as a product of the gains arising from purely 2D mechanisms and an analytical contribution representing 3D growth mechanisms equal to 1+(\\beta Re/Re2D)2G, where \\beta is the spanwise wavenumber and G is a known expression. For example, when the leading eigenmode is an Orr-Sommerfeld mode, it is given by the product of respective gains from the 2D Orr mechanism and an analytical expression representing the 3D lift-up mechanism. Whereas if the leading eigenmode is a Squire mode, the extra gain is shown to be solely due to the 3D lift-up mechanism.

  18. Gene Expression Changes during the Development of Acute Lung Injury Role of Transforming Growth Factor β

    PubMed Central

    Wesselkamper, Scott C.; Case, Lisa M.; Henning, Lisa N.; Borchers, Michael T.; Tichelaar, Jay W.; Mason, John M.; Dragin, Nadine; Medvedovic, Mario; Sartor, Maureen A.; Tomlinson, Craig R.; Leikauf, George D.

    2005-01-01

    Rationale: Acute lung injury can occur from multiple causes, resulting in high mortality. The pathophysiology of nickel-induced acute lung injury in mice is remarkably complex, and the molecular mechanisms are uncertain. Objectives: To integrate molecular pathways and investigate the role of transforming growth factor β (TGF-β) in acute lung injury in mice. Methods: cDNA microarray analyses were used to identify lung gene expression changes after nickel exposure. MAPPFinder analysis of the microarray data was used to determine significantly altered molecular pathways. TGF-β1 protein in bronchoalveolar lavage fluid, as well as the effect of inhibition of TGF-β, was assessed in nickel-exposed mice. The effect of TGF-β on surfactant-associated protein B (Sftpb) promoter activity was measured in mouse lung epithelial cells. Measurements and Main Results: Genes that decreased the most after nickel exposure play important roles in lung fluid absorption or surfactant and phospholipid synthesis, and genes that increased the most were involved in TGF-β signaling. MAPPFinder analysis further established TGF-β signaling to be significantly altered. TGF-β–inducible genes involved in the regulation of extracellular matrix function and fibrinolysis were significantly increased after nickel exposure, and TGF-β1 protein was also increased in the lavage fluid. Pharmacologic inhibition of TGF-β attenuated nickel-induced protein in bronchoalveolar lavage. In addition, treatment with TGF-β1 dose-dependently repressed Sftpb promoter activity in vitro, and a novel TGF-β–responsive region in the Sftpb promoter was identified. Conclusions: These data suggest that TGF-β acts as a central mediator of acute lung injury through the alteration of several different molecular pathways. PMID:16100012

  19. Glucose Stimulation of Transforming Growth Factor-β Bioactivity in Mesangial Cells Is Mediated by Thrombospondin-1

    PubMed Central

    Poczatek, Maria H.; Hugo, Christian; Darley-Usmar, Victor; Murphy-Ullrich, Joanne E.

    2000-01-01

    Glucose is a key factor in the development of diabetic complications, including diabetic nephropathy. The development of diabetic glomerulosclerosis is dependent on the fibrogenic growth factor, transforming growth factor-β (TGF-β). Previously we showed that thrombospondin-1 (TSP-1) activates latent TGF-β both in vitro and in vivo. Activation occurs as the result of specific interactions of latent TGF-β with TSP-1, which potentially alter the conformation of latent TGF-β. As glucose also up-regulates TSP-1 expression, we hypothesized that the increased TGF-β bioactivity observed in rat and human mesangial cells cultured with high glucose concentrations is the result of latent TGF-β activation by autocrine TSP-1. Glucose-induced bioactivity of TGF-β in mesangial cell cultures was reduced to basal levels by peptides from two different sequences that antagonize activation of latent TGF-β by TSP, but not by the plasmin inhibitor, aprotinin. Furthermore, glucose-dependent stimulation of matrix protein synthesis was inhibited by these antagonist peptides. These studies demonstrate that glucose stimulation of TGF-β activity and the resultant matrix protein synthesis are dependent on the action of autocrine TSP-1 to convert latent TGF-β to its biologically active form. These data suggest that antagonists of TSP-dependent TGF-β activation may be the basis of novel therapeutic approaches for ameliorating diabetic renal fibrosis. PMID:11021838

  20. Effects of transforming growth factor beta-1 on growth-regulatory genes in tumour-derived human oral keratinocytes.

    PubMed Central

    Paterson, I. C.; Patel, V.; Sandy, J. R.; Prime, S. S.; Yeudall, W. A.

    1995-01-01

    This study examined the effect of transforming growth factor beta-1 (TGF-beta 1) on c-myc, RB1, junB and p53 expression together with pRb phosphorylation, in carcinoma-derived and normal human oral keratinocytes with a range of inhibitory responses to this ligand. Amplification of c-myc was observed in eight of eight tumour-derived cell lines and resulted in corresponding mRNA expression. The down-regulation of c-myc expression by TGF-beta 1 predominantly reflected growth inhibition by TGF-beta 1, but in two of eight tumour-derived cell lines which were partially responsive to TGF-beta 1 c-myc expression was unaltered by this ligand. While RB1 mRNA levels were unaltered by TGF-beta 1, the ligand caused the accumulation of the underphosphorylated form of the Rb protein in all cells irrespective of TGF-beta 1-induced growth arrest. junB expression was up-regulated by TGF-beta 1 in cells with a range of growth inhibitory responses. All cells contained mutant p53. TGF-beta 1 did not affect p53 mRNA expression in both tumour-derived and normal keratinocytes and there was no alteration in p53 protein levels in keratinocytes expressing stable p53 protein following TGF-beta 1 treatment. The data indicate that TGF-beta-induced growth control can exist independently of the presence of mutant p53 and the control of Rb phosphorylation and c-myc down-regulation. It may be that TGF-beta growth inhibition occurs via multiple mechanisms and that the loss of one pathway during tumour progression does not necessarily result in the abrogation of TGF-beta-induced growth control. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:7547241

  1. Active states and structure transformations in accreting white dwarfs

    NASA Astrophysics Data System (ADS)

    Boneva, Daniela; Kaygorodov, Pavel

    2016-07-01

    Active states in white dwarfs are usually associated with light curve's effects that concern to the bursts, flickering or flare-up occurrences. It is common that a gas-dynamics source exists for each of these processes there. We consider the white dwarf binary stars with accretion disc around the primary. We suggest a flow transformation modeling of the mechanisms that are responsible for ability to cause some flow instability and bring the white dwarfs system to the outburst's development. The processes that cause the accretion rate to sufficiently increase are discussed. Then the transition from a quiescent to an active state is realized. We analyze a quasi-periodic variability in the luminosity of white dwarf binary stars systems. The results are supported with an observational data.

  2. Doppler radar fall activity detection using the wavelet transform.

    PubMed

    Su, Bo Yu; Ho, K C; Rantz, Marilyn J; Skubic, Marjorie

    2015-03-01

    We propose in this paper the use of Wavelet transform (WT) to detect human falls using a ceiling mounted Doppler range control radar. The radar senses any motions from falls as well as nonfalls due to the Doppler effect. The WT is very effective in distinguishing the falls from other activities, making it a promising technique for radar fall detection in nonobtrusive inhome elder care applications. The proposed radar fall detector consists of two stages. The prescreen stage uses the coefficients of wavelet decomposition at a given scale to identify the time locations in which fall activities may have occurred. The classification stage extracts the time-frequency content from the wavelet coefficients at many scales to form a feature vector for fall versus nonfall classification. The selection of different wavelet functions is examined to achieve better performance. Experimental results using the data from the laboratory and real inhome environments validate the promising and robust performance of the proposed detector.

  3. Vascular remodeling in primary pulmonary hypertension. Potential role for transforming growth factor-beta.

    PubMed Central

    Botney, M. D.; Bahadori, L.; Gold, L. I.

    1994-01-01

    Active exogenous transforming growth factor-beta s (TGF-beta s) are potent modulators of extracellular matrix synthesis in cell culture and stimulate matrix synthesis in wounds and other remodeling tissues. The role of endogenous TGF-beta s in remodeling tissues is less well defined. Vascular remodeling in the pulmonary arteries of patients with primary pulmonary hypertension is characterized, in part, by abnormal deposition of immunohistochemically detectable procollagen, thereby identifying actively remodeling vessels. We used this marker of active matrix synthesis to begin defining the in vivo role of TGF-beta in the complex milieu of actively remodeling tissues. Immunohistochemistry using isoform-specific anti-TGF-beta antibodies was performed to determine whether TGF-beta was present in actively remodeling hypertensive pulmonary arteries 20 to 500 microns in diameter. Intense, cell-associated TGF-beta 3 immunoreactivity was observed in the media and neointima of these hypertensive muscular arteries. Immunostaining was present, but less intense, in normal arteries of comparable size. TGF-beta 2 immunoreactivity was observed in normal vessels and was increased slightly in hypertensive vessels, in a pattern resembling TGF-beta 3 immunoreactivity. No staining was associated with the adventitia. TGF-beta 1 immunostaining was either faint or absent in both normal and hypertensive vessels. Comparison of procollagen and TGF-beta localization demonstrated that TGF-beta 2 and TGF-beta 3 colocalized at all sites of procollagen synthesis. However, TGF-beta was observed in vessels, or vascular compartments, where there was no procollagen synthesis. Procollagen immunoreactivity was not present in normal vessels that showed immunoreactivity for TGF-beta 2 and TGF-beta 3. These observations suggest: a) the stimulation of procollagen synthesis by TGF-beta in vivo is more complex than suggested by in vitro studies and b) a potential role for TGF-beta 2 or TGF-beta 3, but not

  4. Proteolytic Processing Regulates Placental Growth Factor Activities*

    PubMed Central

    Hoffmann, Daniel C.; Willenborg, Sebastian; Koch, Manuel; Zwolanek, Daniela; Müller, Stefan; Becker, Ann-Kathrin A.; Metzger, Stephanie; Ehrbar, Martin; Kurschat, Peter; Hellmich, Martin; Hubbell, Jeffrey A.; Eming, Sabine A.

    2013-01-01

    Placental growth factor (PlGF) is a critical mediator of blood vessel formation, yet mechanisms of its action and regulation are incompletely understood. Here we demonstrate that proteolytic processing regulates the biological activity of PlGF. Specifically, we show that plasmin processing of PlGF-2 yields a protease-resistant core fragment comprising the vascular endothelial growth factor receptor-1 binding site but lacking the carboxyl-terminal domain encoding the heparin-binding domain and an 8-amino acid peptide encoded by exon 7. We have identified plasmin cleavage sites, generated a truncated PlGF118 isoform mimicking plasmin-processed PlGF, and explored its biological function in comparison with that of PlGF-1 and -2. The angiogenic responses induced by the diverse PlGF forms were distinct. Whereas PlGF-2 increased endothelial cell chemotaxis, vascular sprouting, and granulation tissue formation upon skin injury, these activities were abrogated following plasmin digestion. Investigation of PlGF/Neuropilin-1 binding and function suggests a critical role for heparin-binding domain/Neuropilin-1 interaction and its regulation by plasmin processing. Collectively, here we provide new mechanistic insights into the regulation of PlGF-2/Neuropilin-1-mediated tissue vascularization and growth. PMID:23645683

  5. Phase transformation process and step growth mechanism of hydroxyapatite whiskers under constant impulsion system

    NASA Astrophysics Data System (ADS)

    Chen, Changlian; Li, Jianqiu; Huang, Zhiliang; Cheng, Xiaokun; Yu, Jun; Wang, Han; Chi, Ru-an; Hu, Yuehua

    2011-07-01

    Hydroxyapatite (HAP) whiskers were synthesized using urea as the precipitator by a phase transformation method, and their phase transformation process and growth mechanism were investigated. The results showed that with the decomposition of urea and the corresponding increase of pH value of the reaction system, dicalcium phosphate anhydrous (DCPA) and octacalcium phosphate (OCP) were precipitated at pH of 3.3-4.3; then Ca 2+ and HPO42- ions began to be released from DCPA at pH values greater than 4.5. Finally HAP whiskers heterogeneously nucleated and grew up into short column crystals along the surface of the OCP flakes. In the absence of the ionic resources, DCPA gradually dissolved and the OCP flakes transformed into HAP continuously and the short columnar HAP whiskers grew up. The aspect ratio of the HAP whiskers with length of 20-100 μm and diameter of 1-2 μm was about 25. The HRTEM and AFM images showed that HAP whiskers grew along the c-axis direction, the (1 0 0) steps were clearly observed at their heads and the straight step lines instead of helical Frank ones were present on the side face of the (1 0 0) steps. The calculation on the basis of the surface energy of the HAP crystal showed that the growth rate of the (0 0 1) plane was the fastest, the growth rate at the homogeneous twist sites was the second and that at heterogeneous twist sites could be the slowest, which were the main factors finally leading to the preferential growth of HAP whiskers along the c-axis direction as well as the formation of the growth steps.

  6. Noncanonical transforming growth factor β (TGFβ) signaling in cranial neural crest cells causes tongue muscle developmental defects.

    PubMed

    Iwata, Jun-ichi; Suzuki, Akiko; Pelikan, Richard C; Ho, Thach-Vu; Chai, Yang

    2013-10-11

    Microglossia is a congenital birth defect in humans and adversely impacts quality of life. In vertebrates, tongue muscle derives from the cranial mesoderm, whereas tendons and connective tissues in the craniofacial region originate from cranial neural crest (CNC) cells. Loss of transforming growth factor β (TGFβ) type II receptor in CNC cells in mice (Tgfbr2(fl/fl);Wnt1-Cre) causes microglossia due to a failure of cell-cell communication between cranial mesoderm and CNC cells during tongue development. However, it is still unclear how TGFβ signaling in CNC cells regulates the fate of mesoderm-derived myoblasts during tongue development. Here we show that activation of the cytoplasmic and nuclear tyrosine kinase 1 (ABL1) cascade in Tgfbr2(fl/fl);Wnt1-Cre mice results in a failure of CNC-derived cell differentiation followed by a disruption of TGFβ-mediated induction of growth factors and reduction of myogenic cell proliferation and differentiation activities. Among the affected growth factors, the addition of fibroblast growth factor 4 (FGF4) and neutralizing antibody for follistatin (FST; an antagonist of bone morphogenetic protein (BMP)) could most efficiently restore cell proliferation, differentiation, and organization of muscle cells in the tongue of Tgfbr2(fl/fl);Wnt1-Cre mice. Thus, our data indicate that CNC-derived fibroblasts regulate the fate of mesoderm-derived myoblasts through TGFβ-mediated regulation of FGF and BMP signaling during tongue development.

  7. Transforming growth factor-alpha in vivo stimulates epithelial cell proliferation in digestive tissues of suckling rats.

    PubMed Central

    Hormi, K; Lehy, T

    1996-01-01

    BACKGROUND: The role that exogenous transforming growth factor-alpha (TGF-alpha) may exert on cell proliferation in vivo is poorly understood. AIM: To investigate the effect of rat TGF-alpha on epithelial cell proliferation in all suckling rat digestive tissues and to compare it with that of rat epidermal growth factor (EGF). ANIMAL AND METHODS: TGF-alpha and EGF were given three times daily either subcutaneously (10 or 20 micrograms/kg) or intraperitoneally (100 micrograms/kg) to rats from the ninth postnatal day. Cell proliferation was assessed through 5-bromo- 2-deoxyuridine incorporation and estimation of labelling indices. RESULTS: For both growth factors, the highest dose given for only two days significantly increased stomach and intestinal weights compared with controls (p < 0.05 to p < 0.001). The proliferative responded depended on the dose given, colonic mucosa being the most sensitive whereas oxyntic mucosa remained unresponsive. TGF-alpha was as potent as EGF in stimulating epithelial cell proliferation in antral, duodenal, and colonic mucosae. However, EGF was more active on oesophageal and jejunal cell proliferation whereas TGF-alpha was more active on pancreatic exocrine cell proliferation and the differences between the two growth factor treated groups were significant. CONCLUSIONS: These results prove for the first time the stimulating effect in vivo of exogenous rat TGF-alpha on epithelial cell proliferation in rat digestive tissues during the developmental period and support a functional role for TGF-alpha at that time. PMID:8944561

  8. Transforming growth factor beta-induced (TGFBI) is an anti-adhesive protein regulating the invasive growth of melanoma cells.

    PubMed

    Nummela, Pirjo; Lammi, Johanna; Soikkeli, Johanna; Saksela, Olli; Laakkonen, Pirjo; Hölttä, Erkki

    2012-04-01

    Melanoma is a malignancy characterized by high invasive/metastatic potential, with no efficient therapy after metastasis. Understanding the molecular mechanisms underlying the invasive/metastatic tendency is therefore important. Our genome-wide gene expression analyses revealed that human melanoma cell lines WM793 and especially WM239 (vertical growth phase and metastatic cells, respectively) overexpress the extracellular matrix (ECM) protein transforming growth factor β induced (TGFBI). In adhesion assays, recombinant TGFBI was strongly anti-adhesive for both melanoma cells and skin fibroblasts. TGFBI further impaired the adhesion of melanoma cells to the adhesive ECM proteins fibronectin, collagen-I, and laminin, known to interact with it. Unexpectedly, WM239 cells migrated/invaded more effectively in three-dimensional collagen-I and Matrigel cultures after knockdown of TGFBI by shRNA expression. However, in the physiological subcutaneous microenvironment in nude mice, after TGFBI knockdown, these cells showed markedly impaired tumor growth and invasive capability; the initially formed small tumors later underwent myxoid degeneration and completely regressed. By contrast, the expanding control tumors showed intense TGFBI staining at the tumor edges, co-localizing with the fibrillar fibronectin/tenascin-C/periostin structures that characteristically surround melanoma cells at invasion fronts. Furthermore, TGFBI was found in similar fibrillar structures in clinical human melanoma metastases as well, co-localizing with fibronectin. These data imply an important role for TGFBI in the ECM deposition and invasive growth of melanoma cells, rendering TGFBI a potential target for therapeutic interventions.

  9. Protein kinase A modulates transforming growth factor-β signaling through a direct interaction with Smad4 protein.

    PubMed

    Yang, Huibin; Li, Gangyong; Wu, Jing-Jiang; Wang, Lidong; Uhler, Michael; Simeone, Diane M

    2013-03-22

    Transforming growth factor β (TGFβ) signaling normally functions to regulate embryonic development and cellular homeostasis. It is increasingly recognized that TGFβ signaling is regulated by cross-talk with other signaling pathways. We previously reported that TGFβ activates protein kinase A (PKA) independent of cAMP through an interaction of an activated Smad3-Smad4 complex and the regulatory subunit of the PKA holoenzyme (PKA-R). Here we define the interaction domains of Smad4 and PKA-R and the functional consequences of this interaction. Using a series of Smad4 and PKA-R truncation mutants, we identified amino acids 290-300 of the Smad4 linker region as critical for the specific interaction of Smad4 and PKA-R. Co-immunoprecipitation assays showed that the B cAMP binding domain of PKA-R was sufficient for interaction with Smad4. Targeting of B domain regions conserved among all PKA-R isoforms and exposed on the molecular surface demonstrated that amino acids 281-285 and 320-329 were required for complex formation with Smad4. Interactions of these specific regions of Smad4 and PKA-R were necessary for TGFβ-mediated increases in PKA activity, CREB (cAMP-response element-binding protein) phosphorylation, induction of p21, and growth inhibition. Moreover, this Smad4-PKA interaction was required for TGFβ-induced epithelial mesenchymal transition, invasion of pancreatic tumor cells, and regulation of tumor growth in vivo.

  10. Transforming growth factor-β signaling in hypertensive remodeling of porcine aorta

    PubMed Central

    Popovic, Natasa; Bridenbaugh, Eric A.; Neiger, Jessemy D.; Hu, Jin-Jia; Vannucci, Marina; Mo, Qianxing; Trzeciakowski, Jerome; Miller, Matthew W.; Fossum, Theresa W.; Humphrey, Jay D.

    2009-01-01

    A porcine aortic coarctation model was used to examine regulation of gene expression in early hypertensive vascular remodeling. Aortic segments were collected proximal (high pressure) and distal (low pressure) to the coarctation after 2 wk of sustained hypertension (mean arterial pressure > 150 mmHg). Porcine 10K oligoarrays used for gene expression profiling of the two regions of aorta revealed downregulation of cytoskeletal and upregulation of extracellular region genes relative to the whole genome. A genomic database search for transforming growth factor-β (TGF-β) control elements showed that 19% of the genes that changed expression due to hypertension contained putative TGF-β control elements. Real-time RT-PCR and microarray analysis showed no change in expression of TGF-β1, TGF-β2, TGF-β3, or bone morphogenetic proteins-2 and -4, yet immunohistochemical staining for phosphorylated SMAD2, an indicator of TGF-β signaling, and for phosphorylated SMAD1/5/8, an indicator of signaling through the bone morphogenetic proteins, showed the highest percentage of positively stained cells in the proximal aortic segments of occluded animals. For TGF-β signaling, this increase was significantly different than for sham-operated controls. Western blot analysis showed no difference in total TGF-β1 protein levels with respect to treatment or aortic segment. Immunohistochemistry showed that the protein levels of latency-associated peptide was decreased in proximal segments of occluded animals. Collectively, these results suggest that activation of TGF-β, but not altered expression, may be a major mechanism regulating early hypertensive vascular remodeling. PMID:19717726

  11. Transforming growth factor beta 1: an autocrine regulator of adrenocortical steroidogenesis.

    PubMed

    Feige, J J; Cochet, C; Savona, C; Shi, D L; Keramidas, M; Defaye, G; Chambaz, E M

    1991-01-01

    Transforming growth factor beta 1 (TGF beta 1) is a member of a large family of structurally related regulatory polypeptides which comprises both functionally similar (TGF beta 1, TGF beta 2, TGF beta 3, TGF beta 4 and TGF beta 5) and functionally distinct proteins. In the past few years, TGF beta 1 has emerged as a multifunctional protein. One of its remarkable properties is its capacity to negatively modulate the differentiated, steroidogenic adrenocortical functions. We present here a review of the results from our recent work related to the effects of TGF beta 1 on bovine adrenocortical cell (zona fasciculata-reticularis) functions. We identified the steroid 17 alpha-hydroxylase (P-450 17 alpha) biosynthetic enzyme and the angiotensin II receptor as major targets whose expression are negatively regulated by TGF beta 1 in these cells. We characterized TGF beta 1 receptors at the surface of adrenocortical cells (mainly type I and type III receptors) and observed that their number is increased under ACTH treatment. Furthermore, we could detect the presence of immunoreactive TGF beta 1 in the bovine adrenal cortex whereas it was undetectable in the adrenal medulla and in the capsule. We also observed that adrenocortical cells secrete TGF beta 1 under a latent form together with large amounts of alpha 2-macroglobulin, a protease inhibitor known to be implied in the latency of TGF beta in serum. Taken together, these observations led us to a working hypothesis, proposing TGF beta 1 as an autocrine and/or paracrine regulator of adrenocortical steroidogenic functions. This concept points out the physiological activation of the latent TGF beta 1 complex as the important limiting step controlling its action in the adrenal cortex.

  12. Transforming growth factor-beta 1 in rheumatoid synovial membrane and cartilage/pannus junction.

    PubMed

    Chu, C Q; Field, M; Abney, E; Zheng, R Q; Allard, S; Feldmann, M; Maini, R N

    1991-12-01

    Transforming growth factor (TGF)-beta has been shown to promote tissue repair and have immunosuppressive actions, and has been proposed to have a role in rheumatoid arthritis (RA). Using immunohistochemical techniques with rabbit F(ab')2 antibodies raised against recombinant human TGF-beta 1, we have detected TGF-beta 1 in the synovial tissue and cartilage/pannus junction (CPJ) from 18/18 patients with RA. TGF-beta 1 was found predominantly in the thickened synovial lining layer in RA, but also detected in a perivascular pattern in the synovial interstitium as well as in occasional cells in the lymphoid aggregates. At the CPJ it was found both in cells at the distinct junction as well as in the transitional region of the diffuse fibroblastic zone. The cells staining for TGF-beta 1 were identified by double immunofluorescence staining as being from the monocyte/macrophage series as well as the type B synovial lining cells. TGF-beta 1 was also detected in the synovial membrane sections from 4/4 patients with systemic lupus erythematosus/mixed connective tissue disease and 5/8 patients with osteoarthritis, in a similar distribution to that seen in RA, and in the lining layer of 1/7 normal synovial membranes. These results add to histological evidence confirming that TGF-beta 1 is present in RA synovial cells and those from other arthritides. The distributions of TGF-beta 1 in RA synovial membrane reflects its known actions, as it can be detected at the CPJ, where it could induce repair, and close to activated cells upon which it may exert an immunosuppressive action.

  13. Cellular localization of transforming growth factor-beta expression in bleomycin-induced pulmonary fibrosis.

    PubMed Central

    Zhang, K.; Flanders, K. C.; Phan, S. H.

    1995-01-01

    Bleomycin-induced pulmonary fibrosis is associated with increased lung transforming growth factor-beta (TGF-beta) gene expression, but cellular localization of the source of this expression has not been unequivocally established. In this study, lung fibrosis was induced in rats by endotracheal bleomycin injection on day 0 and, on selected days afterwards, lungs were harvested for in situ hybridization, immunohistochemical and histochemical analyses for TGF-beta 1 mRNA and protein expression, and cell identification. The results show that control lungs express essentially no detectable TGF-beta 1 mRNA or protein in the parenchyma. Before day 3 after bleomycin treatment, scattered bronchiolar epithelial cells, mononuclear cells, and eosinophils expressed elevated levels of TGF-beta 1. Between days 3 and 14, there was a major increase in the number of eosinophils, myofibroblasts, and fibroblasts strongly expressing TGF-beta 1 mRNA and protein. TGF-beta 1-producing cells were predominantly localized within areas of injury and active fibrosis. After day 14, the intensity and number of TGF-beta 1-expressing cells significantly declined and were predominantly found in fibroblasts in fibrotic areas. The expression of TGF-beta 1 protein was generally coincident with that for mRNA with the exception of bronchiolar epithelial cells in which strong protein expression was unaccompanied by a commensurate increase in mRNA. The study demonstrates that myofibroblasts, fibroblasts, and eosinophils represent the major sources of increased lung TGF-beta 1 expression in this model of pulmonary fibrosis. Images Figure 2 Figure 3 Figure 4 PMID:7543734

  14. Resistance of human squamous carcinoma cells to transforming growth factor beta 1 is a recessive trait.

    PubMed Central

    Reiss, M; Muñoz-Antonia, T; Cowan, J M; Wilkins, P C; Zhou, Z L; Vellucci, V F

    1993-01-01

    Because most human squamous carcinoma cell lines of the aerodigestive and genital tracts are refractory to the antiproliferative action of transforming growth factor beta 1 (TGF beta 1) in vitro, we have begun to identify the causes for resistance of squamous carcinoma cell lines to TGF beta 1 by using somatic cell genetics. Two stable hybrid cell lines (FaDu-HKc.1 and FaDu-HKc.2) were obtained by fusing a TGF beta 1-resistant human squamous carcinoma cell line, FaDu-HygR, with a human papilloma virus 16-immortalized, TGF beta 1-sensitive, human foreskin keratinocyte cell line, HKc-neoR. Whereas TGF beta 1 did not inhibit DNA synthesis in parental FaDu-HygR cells, it reduced DNA synthetic activity of HKc-neoR, FaDu-HKc.1, and FaDu-HKc.2 cells by 75-85% (IC50, 2-5 pM). Although squamous carcinoma cells express lower than normal levels of TGF beta 1 type II receptors on their cell surface, TGF beta 1 type II receptor mRNA was detected in all four cell lines. Recessive genes involved in TGF beta 1 signaling may be localized to the distal portion of chromosome 18q, as this was the sole chromosomal region of homozygous deletion in parental FaDu-HygR cells. Furthermore, our previous observation that mutant p53 decreases sensitivity of keratinocytes to TGF beta 1 was supported by the finding that the level of the mutant p53 protein expressed by the hybrid cell lines was greatly reduced. In summary, TGF beta 1 resistance of FaDu cells appears to be recessive and is presumably due to the loss of one or more post-receptor elements of the signaling pathway. Images Fig. 1 Fig. 2 Fig. 4 Fig. 5 Fig. 6 PMID:8327510

  15. Transforming Growth Factor-β Signaling Pathway in Patients with Kawasaki Disease

    PubMed Central

    Shimizu, Chisato; Jain, Sonia; Lin, Kevin O.; Molkara, Delaram; Frazer, Jeffrey R.; Sun, Shelly; Baker, Annette L.; Newburger, Jane W.; Rowley, Anne H.; Shulman, Stanford T.; Davila, Sonia; Hibberd, Martin L.; Burgner, David; Breunis, Willemijn B.; Kuijpers, Taco W.; Wright, Victoria J.; Levin, Michael; Eleftherohorinou, Hariklia; Coin, Lachlan; Popper, Stephen J.; Relman, David A.; Fury, Wen; Lin, Calvin; Mellis, Scott; Tremoulet, Adriana H.; Burns, Jane C.

    2011-01-01

    Background Transforming growth factor (TGF)-β is a multifunctional peptide that is important in T-cell activation and cardiovascular remodeling, both of which are important features of Kawasaki disease (KD). We postulated that variation in TGF-β signaling might be important in KD susceptibility and disease outcome. Methods and Results We investigated genetic variation in 15 genes belonging to the TGF-β pathway in a total 771 KD subjects of mainly European descendent from the US, UK, Australia and the Netherlands. We analyzed transcript abundance patterns using microarray and RT-PCR for these same genes and measured TGF-β2 protein levels in plasma. Genetic variants in TGFB2, TGFBR2 and SMAD3 and their haplotypes were consistently and reproducibly associated with KD susceptibility, coronary artery aneurysm formation, aortic root dilatation, and intravenous immunoglobulin treatment response in different cohorts. A SMAD3 haplotype associated with KD susceptibility replicated in two independent cohorts and an intronic SNP in a separate haplotype block was also strongly associated (A/G, rs4776338) (p=0.000022, OR 1.50, 95% CI 1.25-1.81). Pathway analysis using all 15 genes further confirmed the importance of the TGF-β pathway in KD pathogenesis. Whole blood transcript abundance for these genes and TGF-β2 plasma protein levels changed dynamically over the course of the illness. Conclusions These studies suggest that genetic variation in the TGF-β pathway influences KD susceptibility, disease outcome, and response to therapy and that aortic root and coronary artery Z scores can be used for phenotype/genotype analyses. Analysis of transcript abundance and protein levels further support the importance of this pathway in KD pathogenesis. PMID:21127203

  16. Abelson murine leukemia virus transformation-defective mutants with impaired P120-associated protein kinase activity.

    PubMed Central

    Reynolds, F H; Van de Ven, W J; Stephenson, J R

    1980-01-01

    Several transformation-defective (td) mutants of Abelson murine leukemia virus (AbLV) are described. Cells nonproductively infected with such mutants exhibited a high degree of growth contact inhibition, failed to form colonies in soft agar, lacked rescuable transforming virus, and were as susceptible as uninfected control cells to transformation by wild-type (wt) AbLV pseudotype virus. In addition, each of several td AbLV nonproductively infected cell clones analyzed was found to be nontumorigenic in vivo. Biochemical analysis of td mutant AbLV-infected clones revealed levels of expression of the major AbLV translational product, P120, and a highly related 80,000-Mr AbLV-encoded protein, P80, at concentrations analogous to those in wt AbLV-transformed cells. Although the AbLV-specific 120,000-Mr polyproteins expressed in td mutant AbLV-infected clones were indistinguishable from those in wt AbLV-transformed lines with respect to molecular weight and [35S]methionine tryptic peptide composition, they each differed from wt AbLV P120 in their patterns of post-translational phosphorylation. A previously described AbLV-associated protein kinase activity is shown to recognize as substrate a major tyrosine-specific acceptor site(s) contained within a single well-resolved tryptic peptide common to both AbLV P120 and P80. In vitro [gamma-32P]ATP-mediated labeling of this phosphorylation site was reduced to below detectable levels in td mutant nonproductively infected cell clones. These findings establish that the AbLV-encoded polyprotein P120 and its associated protein kinase activity are involved in AbLV tumorigenesis. Images PMID:6253663

  17. Transcriptional pathways associated with the slow growth phenotype of transformed Anaplasma marginale

    PubMed Central

    2013-01-01

    Background The ability to genetically manipulate bacteria has been fundamentally important for both basic biological discovery and translational research to develop new vaccines and antibiotics. Experimental alteration of the genetic content of prokaryotic pathogens has revealed both expected functional relationships and unexpected phenotypic consequences. Slow growth phenotypes have been reported for multiple transformed bacterial species, including extracellular and intracellular pathogens. Understanding the genes and pathways responsible for the slow growth phenotype provides the opportunity to develop attenuated vaccines as well as bacteriostatic antibiotics. Transformed Anaplasma marginale, a rickettsial pathogen, exhibits slow growth in vitro and in vivo as compared to the parent wild type strain, providing the opportunity to identify the underlying genes and pathways associated with this phenotype. Results Whole genome transcriptional profiling allowed for identification of specific genes and pathways altered in transformed A. marginale. Genes found immediately upstream and downstream of the insertion site, including a four gene operon encoding key outer membrane proteins, were not differentially transcribed between wild type and transformed A. marginale. This lack of significant difference in transcription of flanking genes and the large size of the insert relative to the genome were consistent with a trans rather than a cis effect. Transcriptional profiling across the complete genome identified the most differentially transcribed genes, including an iron transporter, an RNA cleaving enzyme and several genes involved in translation. In order to confirm the trend seen in translation-related genes, K-means clustering and Gene Set Enrichment Analysis (GSEA) were applied. These algorithms allowed evaluation of the behavior of genes as groups that share transcriptional status or biological function. Clustering and GSEA confirmed the initial observations and

  18. Phenol oxidase activity in secondary transformed peat-moorsh soils

    NASA Astrophysics Data System (ADS)

    Styła, K.; Szajdak, L.

    2009-04-01

    The chemical composition of peat depends on the geobotanical conditions of its formation and on the depth of sampling. The evolution of hydrogenic peat soils is closely related to the genesis of peat and to the changes in water conditions. Due to a number of factors including oscillation of ground water level, different redox potential, changes of aerobic conditions, different plant communities, and root exudes, and products of the degradation of plant remains, peat-moorsh soils may undergo a process of secondary transformation conditions (Sokolowska et al. 2005; Szajdak et al. 2007). Phenol oxidase is one of the few enzymes able to degrade recalcitrant phenolic materials as lignin (Freeman et al. 2004). Phenol oxidase enzymes catalyze polyphenol oxidation in the presence of oxygen (O2) by removing phenolic hydrogen or hydrogenes to from radicals or quinines. These products undergo nucleophilic addition reactions in the presence or absence of free - NH2 group with the eventual production of humic acid-like polymers. The presence of phenol oxidase in soil environments is important in the formation of humic substances a desirable process because the carbon is stored in a stable form (Matocha et al. 2004). The investigations were carried out on the transect of peatland 4.5 km long, located in the Agroecological Landscape Park host D. Chlapowski in Turew (40 km South-West of Poznań, West Polish Lowland). The sites of investigation were located along Wyskoć ditch. The following material was taken from four chosen sites marked as Zbechy, Bridge, Shelterbelt and Hirudo in two layers: cartel (0-50cm) and cattle (50-100cm). The object of this study was to characterize the biochemical properties by the determination of the phenol oxidize activity in two layers of the four different peat-moors soils used as meadow. The phenol oxidase activity was determined spectrophotometrically by measuring quinone formation at λmax=525 nm with catechol as substrate by method of Perucci

  19. Transforming growth factor β recruits persistent MAPK signaling to regulate long-term memory consolidation in Aplysia californica.

    PubMed

    Shobe, Justin; Philips, Gary T; Carew, Thomas J

    2016-05-01

    In this study, we explore the mechanistic relationship between growth factor signaling and kinase activity that supports the protein synthesis-dependent phase of long-term memory (LTM) consolidation for sensitization ofAplysia Specifically, we examine LTM for tail shock-induced sensitization of the tail-elicited siphon withdrawal (T-SW) reflex, a form of memory that requires both (i) extracellular signal-regulated kinase (ERK1/2; MAPK) activity within identified sensory neurons (SNs) that mediate the T-SW and (ii) the activation of transforming growth factor β (TGFβ) signaling. We now report that repeated tail shocks that induce intermediate-term (ITM) and LTM for sensitization, also induce a sustained post-training phase of MAPK activity in SNs (lasting at least 1 h). We identified two mechanistically distinct phases of post-training MAPK: (i) an immediate phase that does not require ongoing protein synthesis or TGFβ signaling, and (ii) a sustained phase that requires both protein synthesis and extracellular TGFβ signaling. We find that LTM consolidation requires sustained MAPK, and is disrupted by inhibitors of protein synthesis and TGFβ signaling during the consolidation window. These results provide strong evidence that TGFβ signaling sustains MAPK activity as an essential mechanistic step for LTM consolidation.

  20. Cadmium-transformed cells in the in vitro cell transformation assay reveal different proliferative behaviours and activated pathways.

    PubMed

    Forcella, M; Callegaro, G; Melchioretto, P; Gribaldo, L; Frattini, M; Stefanini, F M; Fusi, P; Urani, C

    2016-10-01

    The in vitro Cell Transformation Assay (CTA) is a powerful tool for mechanistic studies of carcinogenesis. The endpoint is the classification of transformed colonies (foci) by means of standard morphological features. To increase throughput and reliability of CTAs, one of the suggested follow-up activities is to exploit the comprehension of the mechanisms underlying cell transformation. To this end, we have performed CTAs testing CdCl2, a widespread environmental contaminant classified as a human carcinogen with the underlying mechanisms of action not completely understood. We have isolated and re-seeded the cells at the end (6weeks) of in vitro CTAs to further identify the biochemical pathways underlying the transformed phenotype of foci. Morphological evaluations and proliferative assays confirmed the loss of contact-inhibition and the higher proliferative rate of transformed clones. The biochemical analysis of EGFR pathway revealed that, despite the same initial carcinogenic stimulus (1μM CdCl2 for 24h), transformed clones are characterized by the activation of two different molecular pathways: proliferation (Erk activation) or survival (Akt activation). Our preliminary results on molecular characterization of cell clones from different foci could be exploited for CTAs improvement, supporting the comprehension of the in vivo process and complementing the morphological evaluation of foci.

  1. Expression of transforming growth factor-beta 1 in normal and dyschondroplastic articular growth cartilage of the young horse.

    PubMed

    Henson, F M; Schofield, P N; Jeffcott, L B

    1997-11-01

    This study describes the distribution pattern of transforming growth factor-beta 1 (TGF-beta 1) mRNA and protein in normal pre- and post natal growth cartilage and alterations present in lesions of dyschondroplasia (osteochondrosis). TGF-beta 1 expression and immunoreactivity have been investigated by in situ hybridisation and immunolocalisation in the articular/epiphyseal growth cartilage of the lateral trochlear ridge of the distal femur. Cartilage was obtained from 19 normal Thoroughbred horses (5 prenatal and 14 post natal horses) and 15 post natal horses with dyschondroplasia (DCP). TGF-beta 1 mRNA expression and immunoreactivity were detected in the proliferative and upper hypertrophic zones in both pre- and post natal normal articular/epiphyseal cartilage. However, mRNA itself was only detected in the mid- and lower hypertrophic zones. Immunoreactivity was identified intracellularly with some nuclear staining observed. In focal lesions of DCP mRNA expression and immunoreactivity were reduced compared to normal cartilage, but strong mRNA expression was observed in the chondrocyte clusters immediately surrounding a lesion of DCP. The results described in this study demonstrate alterations in TGF-beta 1 dyschondroplastic lesions and indicate that it could be involved in the pathogenesis of this condition in the horse.

  2. Control of human glioma cell growth, migration and invasion in vitro by transforming growth factor beta 1.

    PubMed Central

    Merzak, A.; McCrea, S.; Koocheckpour, S.; Pilkington, G. J.

    1994-01-01

    Factors involved in the control of the biological properties of gliomas, the major form of brain tumour in man, are poorly documented. We investigated the role of transforming growth factor beta 1 (TGF-beta 1) in the control of proliferation of human glioma cell lines as well as normal human fetal brain cells. The data presented show that TGF-beta 1 exerts a growth-inhibitory action on both human fetal brain cells and three cell lines derived from human glioma of different grades of malignancy. In addition, this growth-inhibitory effect is dose dependent and serum independent. Since TGF-beta 1 is known to be involved in the control of cell migration during ontogenesis and oncogenesis, we investigated the role of this factor in the motile and invasive behaviour that characterises human gliomas in vivo. TGF-beta 1 was found to elicit a strong stimulation of migration and invasiveness of glioma cells in vitro. In combination with recent data showing an inverse correlation between TGF-beta 1 expression in human gliomas and survival, these findings may suggest that TGF-beta 1 plays an important role in the malignant progression of gliomas in man. A study of the molecular mechanisms involved in the antiproliferative action and the invasion-promoting action of TGF-beta 1 may help to identify new targets in therapy for brain tumours. A combined antiproliferative and anti-invasive therapy could be envisaged. Images Figure 3 PMID:8054266

  3. The evidence for the role of transforming growth factor-beta in the formation of abnormal scarring.

    PubMed

    Chalmers, Richard L

    2011-06-01

    The complex biological and physiological mechanisms that result in poor quality scarring are still not fully understood. This review looks at current evidence of the role of transforming growth factor-beta (TGFβ) in this pathological process.

  4. Transformation Pathways of the Recalcitrant Pharmaceutical Compound Carbamazepine by the White-Rot Fungus Pleurotus ostreatus: Effects of Growth Conditions.

    PubMed

    Golan-Rozen, Naama; Seiwert, Bettina; Riemenschneider, Christina; Reemtsma, Thorsten; Chefetz, Benny; Hadar, Yitzhak

    2015-10-20

    The widely used anticonvulsant pharmaceutical carbamazepine is recalcitrant in many environmental niches and thus poses a challenge in wastewater treatment. We followed the decomposition of carbamazepine by the white-rot fungus Pleurotus ostreatus in liquid culture compared to solid-state fermentation on lignocellulosic substrate where different enzymatic systems are active. Carbamazepine metabolites were identified using liquid chromatography-high-resolution mass spectrometry (LC-Q-TOF-MS). In liquid culture, carbamazepine was only transformed to 10,11-epoxy carbamazepine and 10,11-dihydroxy carbamazepine as a dead-end product. During solid-state fermentation, carbamazepine metabolism resulted in the generation of an additional 22 transformation products, some of which are toxic. Under solid-state-fermentation conditions, 10,11-epoxy carbamazepine was further metabolized via acridine and 10,11-dihydroxy carbamazepine pathways. The latter was further metabolized via five subpathways. When (14)C-carbonyl-labeled carbamazepine was used as the substrate, (14)C-CO2 release amounted to 17.4% of the initial radioactivity after 63 days of incubation. The proposed pathways were validated using metabolites (10,11-epoxy carbamazepine, 10,11-dihydroxy carbamazepine, and acridine) as primary substrates and following their fate at different time points. This work highlights the effect of growth conditions on the transformation pathways of xenobiotics. A better understanding of the fate of pollutants during bioremediation treatments is important for establishment of such technologies.

  5. Hepatocyte growth factor and transforming growth factor beta regulate 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase gene expression in rat hepatocyte primary cultures.

    PubMed Central

    Joaquin, M; Rosa, J L; Salvadó, C; López, S; Nakamura, T; Bartrons, R; Gil, J; Tauler, A

    1996-01-01

    Hepatocyte growth factor (HGF) and transforming growth factor beta (TGF-beta) are believed to be of major importance for hepatic regeneration after liver damage. We have studied the effect of these growth factors on fructose 2,6-bisphosphate (Fru-2,6-P2) levels and the expression of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (6PF2K/Fru-2,6-BPase) in rat hepatocyte primary cultures. Our results demonstrate that HGF activates the expression of the 6PF2K/Fru-2,6-BPase gene by increasing the levels of its mRNA. As a consequence of this activation, the amount of 6PF2K/Fru-2,6-BPase protein and 6-phosphofructo-2-kinase activity increased, which was reflected by a rise in Fru-2,6-P2 levels. In contrast, TGF-beta decreased the levels of 6PF2K/Fru-2,6-BPase mRNA, which led to a decrease in the amount of 6PF2K/Fru-2,6-BPase protein and Fru-2,6-P2. The different actions of HGF and TGF-beta on 6PF2K/Fru-2,6-BPase gene expression are concomitant with their effect on cell proliferation. Here we show that, in the absence of hormones, primary cultures of hepatocytes express the F-type isoenzyme. In addition, HGF increases the expression of this isoenzyme, and dexamethasone activates the L-type isoform. HGF and TGF-beta were able to inhibit this activation. PMID:8660288

  6. Expression of transforming growth factor-β2in vitreous body and adjacent tissues during prenatal development of human eye.

    PubMed

    Sukhikh, G T; Panova, I G; Smirnova, Yu A; Milyushina, L A; Firsova, N V; Markitantova, Yu V; Poltavtseva, R A; Zinov'eva, R D

    2010-12-01

    Expression of transforming growth factor-β2 was detected by PCR in the vitreous body, lens, retina, and ciliary-iris complex of human eye at early stages of fetal development. Immunochemical assay of the corresponding protein in eye tissues revealed a correlation between the localization of transforming growth factor-β2 and the development of intraocular hyaloid vascular network, its regression, formation of the vitreous body, and development of definite retinal vessels.

  7. Transforming growth factor alpha promotes osteosarcoma metastasis by ICAM-1 and PI3K/Akt signaling pathway.

    PubMed

    Hou, Chun-Han; Lin, Feng-Ling; Tong, Kai-Biao; Hou, Sheng-Mon; Liu, Ju-Fang

    2014-06-15

    Osteosarcoma is the most common primary malignancy of bone and is characterized by a high malignant and metastatic potential. Transforming growth factor alpha (TGF-α) is classified as the EGF (epidermal growth factor)-like family, which is involved in cancer cellular activities such as proliferation, motility, migration, adhesion and invasion abilities. However, the effect of TGF-α on human osteosarcoma is largely unknown. We found that TGF-α increased the cell migration and expression of intercellular adhesion molecule-1 (ICAM-1) in human osteosarcoma cells. Transfection of cells with ICAM-1 siRNA reduced TGF-α-mediated cell migration. We also found that the phosphatidylinositol 3'-kinase (PI3K)/Akt/NF-κB pathway was activated after TGF-α treatment, and TGF-α-induced expression of ICAM-1 and cell migration was inhibited by the specific inhibitors and siRNAs of PI3K, Akt, and NF-κB cascades. In addition, knockdown of TGF-α expression markedly decreased cell metastasis in vitro and in vivo. Our results indicate that TGF-α/EGFR interaction elicits PI3K and Akt activation, which in turn activates NF-κB, resulting in the expression of ICAM-1 and contributing the migration of human osteosarcoma cells.

  8. Transforming growth factor β as regulator of cancer stemness and metastasis

    PubMed Central

    Bellomo, Claudia; Caja, Laia; Moustakas, Aristidis

    2016-01-01

    Key elements of cancer progression towards metastasis are the biological actions of cancer stem cells and stromal cells in the tumour microenvironment. Cross-communication between tumour and stromal cells is mediated by secreted cytokines, one of which, the transforming growth factor β (TGFβ), regulates essentially every cell within the malignant tissue. In this article, we focus on the actions of TGFβ on cancer stem cells, cancer-associated fibroblasts and immune cells that assist the overall process of metastatic dissemination. We aim at illustrating intricate connections made by various cells in the tumour tissue and which depend on the action of TGFβ. PMID:27537386

  9. Phase transformations during the growth of paracetamol crystals from the vapor phase

    NASA Astrophysics Data System (ADS)

    Belyaev, A. P.; Rubets, V. P.; Antipov, V. V.; Bordei, N. S.

    2014-07-01

    Phase transformations during the growth of paracetamol crystals from the vapor phase are studied by differential scanning calorimetry. It is found that the vapor-crystal phase transition is actually a superposition of two phase transitions: a first-order phase transition with variable density and a second-order phase transition with variable ordering. The latter, being a diffuse phase transition, results in the formation of a new, "pretransition," phase irreversibly spent in the course of the transition, which ends in the appearance of orthorhombic crystals. X-ray diffraction data and micrograph are presented.

  10. Regulation of Transforming Growth Factor–Beta in Diabetic Nephropathy: Implications for Treatment

    PubMed Central

    Zhu, Yanqing; Kataoka Usui, Hitomi; Sharma, Kumar

    2007-01-01

    The recognition of the drivers of matrix accumulation as a therapeutic target for diabetic nephropathy is accepted by the Nephrology and pharmaceutical community. Interventions focused around Transforming Growth Factor–beta (TGF–β) will likely be an important area of clinical investigation in the near future. Understanding the various pathways involved in stimulating TGF–β in the diabetic kidney is of paramount importance in devising strategies to combat the development and progression of diabetic nephropathy. In this review we highlight the major pathways involved in stimulating TGF–β production by elevated glucose and discuss the therapeutic implications. PMID:17418684

  11. Transforming growth factor-β in breast cancer: too much, too late

    PubMed Central

    Barcellos-Hoff, Mary Helen; Akhurst, Rosemary J

    2009-01-01

    The contribution of transforming growth factor (TGF)β to breast cancer has been studied from a myriad perspectives since seminal studies more than two decades ago. Although the action of TGFβ as a canonical tumor suppressor in breast is without a doubt, there is compelling evidence that TGFβ is frequently subverted in a malignant plexus that drives breast cancer. New knowledge that TGFβ regulates the DNA damage response, which underlies cancer therapy, reveals another facet of TGFβ biology that impedes cancer control. Too much TGFβ, too late in cancer progression is the fundamental motivation for pharmaceutical inhibition. PMID:19291273

  12. Immunocytochemical study of transforming growth factor expression in benign and malignant gliomas.

    PubMed Central

    Samuels, V.; Barrett, J. M.; Bockman, S.; Pantazis, C. G.; Allen, M. B.

    1989-01-01

    Immunocytochemical studies using polyclonal antibodies to epidermal growth factor (EGF) and transforming growth factor (TGF) alpha and beta were performed on 20 cases of human gliomas. EGF immunoreactive material was detected in both benign and malignant glial tumors. In addition, EGF immunoreactive material was detected in normal brain. TGF-beta was detected in both benign and malignant tumors, but was not detected in normal brain. In contrast, TGF-alpha was highly conserved in its expression, occurring predominantly in malignant compared with benign or normal brain tissue (P less than 0.0001). In malignant gliomas, glioblastomas contained 76% TGF-alpha reactivity (immunoreactive product), and anaplastic types contained 85% reactivity. Benign gliomas contained only 13% TGF-alpha reactivity. These findings support the role of TGF-alpha as an oncoprotein marker in brain neoplasms. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:2705509

  13. Roles for Transforming Growth Factor Beta Superfamily Proteins in Early Folliculogenesis

    PubMed Central

    Trombly, Daniel J.; Woodruff, Teresa K.; Mayo, Kelly E.

    2010-01-01

    Primordial follicle formation and the subsequent transition of follicles to the primary and secondary stages encompass the early events during folliculogenesis in mammals. These processes establish the ovarian follicle pool and prime follicles for entry into subsequent growth phases during the reproductive cycle. Perturbations during follicle formation can affect the size of the primordial follicle pool significantly, and alterations in follicle transition can cause follicles to arrest at immature stages or result in premature depletion of the follicle reserve. Determining the molecular events that regulate primordial follicle formation and early follicle growth may lead to the development of new fertility treatments. Over the last decade, many of the growth factors and signaling proteins that mediate the early stages of folliculogenesis have been identified using mouse genetic models, in vivo injection studies, and ex vivo organ culture approaches. These studies reveal important roles for the transforming growth factor β (TGF-β) superfamily of proteins in the ovary. This article reviews these roles for TGF-β family proteins and focuses in particular on work from our laboratories on the functions of activin in early folliculogenesis. PMID:19197801

  14. Epigenetic mediated transcriptional activation of WNT5A participates in arsenical-associated malignant transformation

    SciTech Connect

    Jensen, Taylor J.; Wozniak, Ryan J.; Eblin, Kylee E.; Wnek, Sean M.; Gandolfi, A. Jay; Futscher, Bernard W.

    2009-02-15

    Arsenic is a human carcinogen with exposure associated with cancer of the lung, skin, and bladder. Many potential mechanisms have been implicated as playing a role in the process of arsenical-induced malignancy including the perturbation of signaling pathways and aberrant epigenetic regulation. We initiated studies to examine the role of a member of the non-canonical WNT signaling pathway, WNT5A, in UROtsa cells and arsenite [URO-ASSC] and monomethylarsonous acid [URO-MSC] malignantly transformed variants. We present data herein that suggest that WNT5A is transcriptionally activated during arsenical-induced malignant transformation. This WNT5A transcriptional activation is correlated with the enrichment of permissive histone modifications and the reduction of repressive modifications in the WNT5A promoter region. The epigenetic activation of WNT5A expression and acetylation of its promoter remain after the removal of the arsenical, consistent with the maintenance of an anchorage independent growth phenotype in these cells. Additionally, treatment with epigenetic modifying drugs supports a functional role for these epigenetic marks in controlling gene expression. Reduction of WNT5A using lentiviral shRNA greatly attenuated the ability of these cells to grow in an anchorage independent fashion. Extension of our model into human bladder cancer cell lines indicates that each of the cell lines examined also express WNT5A. Taken together, these data suggest that the epigenetic remodeling of the WNT5A promoter is correlated with its transcriptional activation and this upregulation likely participates in arsenical-induced malignant transformation.

  15. Epigenetic Mediated Transcriptional Activation of WNT5A Participates in Arsenical-Associated Malignant Transformation

    PubMed Central

    Jensen, Taylor J.; Wozniak, Ryan J.; Eblin, Kylee E.; Wnek, Sean M.; Gandolfi, A. Jay; Futscher, Bernard W.

    2015-01-01

    Arsenic is a human carcinogen with exposure associated with cancer of the lung, skin, and bladder. Many potential mechanisms have been implicated as playing a role in the process of arsenical-induced malignancy including the perturbation of signaling pathways and aberrant epigenetic regulation. We initiated studies to examine the role of a member of the non-canonical WNT signaling pathway, WNT5A, in UROtsa cells and arsenite [URO-ASSC] and monomethylarsonous acid [URO-MSC] malignantly transformed variants. We present data herein that suggests that WNT5A is transcriptionally activated during arsenical-induced malignant transformation. This WNT5A transcriptional activation is correlated with the enrichment of permissive histone modifications and the reduction of repressive modifications in the WNT5A promoter region. The epigenetic activation of WNT5A expression and acetylation of its promoter remain after the removal of the arsenical, consistent with the maintenance of an anchorage independent growth phenotype in these cells. Additionally, treatment with epigenetic modifying drugs supports a functional role for these epigenetic marks in controlling gene expression. Reduction of WNT5A using lentiviral shRNA greatly attenuated the ability of these cells to grow in an anchorage independent fashion. Extension of our model into human bladder cancer cell lines indicate that each of the cell lines examined also express WNT5A. Taken together, these data suggest that the epigenetic remodeling of the WNT5A promoter is correlated with its transcriptional activation and this upregulation likely participates in arsenical-induced malignant transformation. PMID:19061910

  16. Epigenetic mediated transcriptional activation of WNT5A participates in arsenical-associated malignant transformation.

    PubMed

    Jensen, Taylor J; Wozniak, Ryan J; Eblin, Kylee E; Wnek, Sean M; Gandolfi, A Jay; Futscher, Bernard W

    2009-02-15

    Arsenic is a human carcinogen with exposure associated with cancer of the lung, skin, and bladder. Many potential mechanisms have been implicated as playing a role in the process of arsenical-induced malignancy including the perturbation of signaling pathways and aberrant epigenetic regulation. We initiated studies to examine the role of a member of the non-canonical WNT signaling pathway, WNT5A, in UROtsa cells and arsenite [URO-ASSC] and monomethylarsonous acid [URO-MSC] malignantly transformed variants. We present data herein that suggest that WNT5A is transcriptionally activated during arsenical-induced malignant transformation. This WNT5A transcriptional activation is correlated with the enrichment of permissive histone modifications and the reduction of repressive modifications in the WNT5A promoter region. The epigenetic activation of WNT5A expression and acetylation of its promoter remain after the removal of the arsenical, consistent with the maintenance of an anchorage independent growth phenotype in these cells. Additionally, treatment with epigenetic modifying drugs supports a functional role for these epigenetic marks in controlling gene expression. Reduction of WNT5A using lentiviral shRNA greatly attenuated the ability of these cells to grow in an anchorage independent fashion. Extension of our model into human bladder cancer cell lines indicates that each of the cell lines examined also express WNT5A. Taken together, these data suggest that the epigenetic remodeling of the WNT5A promoter is correlated with its transcriptional activation and this upregulation likely participates in arsenical-induced malignant transformation.

  17. Cyclic AMP induces transforming growth factor beta 2 gene expression and growth arrest in the human androgen-independent prostate carcinoma cell line PC-3.

    PubMed Central

    Bang, Y J; Kim, S J; Danielpour, D; O'Reilly, M A; Kim, K Y; Myers, C E; Trepel, J B

    1992-01-01

    The standard therapy for advanced prostate cancer is androgen ablation. Despite transitory responses, hormonally treated patients ultimately relapse with androgen-independent disease that is resistant to further hormonal manipulation and cytotoxic chemotherapy. To develop an additional approach to the treatment of advanced prostate cancer, we have been studying the signal transductions controlling the growth of human androgen-independent prostate carcinoma cell lines. We report here that elevation of intracellular cAMP markedly inhibits the growth of the hormone-refractory cell line PC-3. To examine the mechanism of cAMP action in PC-3 cells, we tested the effect of the cAMP analog dibutyryl cAMP (Bt2-cAMP) on the regulation of the potent negative growth factor transforming growth factor beta (TGF-beta). Bt2-cAMP selectively induced the secretion of TGF-beta 2 and not TGF-beta 1 by PC-3 cells. This TGF-beta 2 was shown to be bioactive by using the CCL-64 mink lung cell assay. TGF-beta 1 was not activated despite being present at 3-fold higher concentrations than TGF-beta 2. Northern analysis showed that Bt2-cAMP induced an increase in the five characteristic TGF-beta 2 transcripts and had no effect on the level of TGF-beta 1 or TGF-beta 3 transcripts. TGF-beta 2 induction was only weakly enhanced by cycloheximide and was completely inhibited by actinomycin D. These data show that Bt2-cAMP induces the expression of active TGF-beta 2 by PC-3 prostate carcinoma cells, suggesting a new approach to the treatment of prostate cancer and a new molecular mechanism of cAMP action. Images PMID:1373503

  18. Strong magnetic field-assisted growth of carbon nanofibers and its microstructural transformation mechanism

    NASA Astrophysics Data System (ADS)

    Luo, Chengzhi; Fu, Qiang; Pan, Chunxu

    2015-03-01

    It is well-known that electric and magnetic fields can control the growth direction, morphology and microstructure of one-dimensional carbon nanomaterials (1-DCNMs), which plays a key role for its potential applications in micro-nano-electrics and devices. In this paper, we introduce a novel process for controlling growth of carbon nanofibers (CNFs) with assistance of a strong magnetic field (up to 0.5 T in the center) in a chemical vapor deposition (CVD) system. The results reveal that: 1) The CNFs get bundled when grown in the presence of a strong magnetic field and slightly get aligned parallel to the direction of the magnetic field; 2) The CNFs diameter become narrowed and homogenized with increase of the magnetic field; 3) With the increase of the magnetic field, the microstructure of CNFs is gradually changed, i.e., the strong magnetic field makes the disordered ``solid-cored'' CNFs transform into a kind of bamboo-liked carbon nanotubes; 4) We propose a mechanism that the reason for these variations and transformation is due to diamagnetic property of carbon atoms, so that it has direction selectivity in the precipitation process.

  19. Strong magnetic field-assisted growth of carbon nanofibers and its microstructural transformation mechanism

    PubMed Central

    Luo, Chengzhi; Fu, Qiang; Pan, Chunxu

    2015-01-01

    It is well-known that electric and magnetic fields can control the growth direction, morphology and microstructure of one-dimensional carbon nanomaterials (1-DCNMs), which plays a key role for its potential applications in micro-nano-electrics and devices. In this paper, we introduce a novel process for controlling growth of carbon nanofibers (CNFs) with assistance of a strong magnetic field (up to 0.5 T in the center) in a chemical vapor deposition (CVD) system. The results reveal that: 1) The CNFs get bundled when grown in the presence of a strong magnetic field and slightly get aligned parallel to the direction of the magnetic field; 2) The CNFs diameter become narrowed and homogenized with increase of the magnetic field; 3) With the increase of the magnetic field, the microstructure of CNFs is gradually changed, i.e., the strong magnetic field makes the disordered “solid-cored” CNFs transform into a kind of bamboo-liked carbon nanotubes; 4) We propose a mechanism that the reason for these variations and transformation is due to diamagnetic property of carbon atoms, so that it has direction selectivity in the precipitation process. PMID:25761381

  20. Constitutive Smad linker phosphorylation in melanoma: a mechanism of resistance to transforming growth factor-β-mediated growth inhibition.

    PubMed

    Cohen-Solal, Karine A; Merrigan, Kim T; Chan, Joseph L-K; Goydos, James S; Chen, Wenjin; Foran, David J; Liu, Fang; Lasfar, Ahmed; Reiss, Michael

    2011-06-01

    Melanoma cells are resistant to transforming growth factor-β (TGFβ)-induced cell-cycle arrest. In this study, we investigated a mechanism of resistance involving a regulatory domain, called linker region, in Smad2 and Smad3, main downstream effectors of TGFβ. Melanoma cells in culture and tumor samples exhibited constitutive Smad2 and Smad3 linker phosphorylation. Treatment of melanoma cells with the MEK1/2 inhibitor, U0126, or the two pan-CDK and GSK3 inhibitors, Flavopiridol and R547, resulted in decreased linker phosphorylation of Smad2 and Smad3. Overexpression of the linker phosphorylation-resistant Smad3 EPSM mutant in melanoma cells resulted in an increase in expression of p15(INK4B) and p21(WAF1) , as compared with cells transfected with wild-type (WT) Smad3. In addition, the cell numbers of EPSM Smad3-expressing melanoma cells were significantly reduced compared with WT Smad3-expressing cells. These results suggest that the linker phosphorylation of Smad3 contributes to the resistance of melanoma cells to TGFβ-mediated growth inhibition.

  1. Growth Hormone Induces Transforming Growth Factor-Beta-Induced Protein in Podocytes: Implications for Podocyte Depletion and Proteinuria.

    PubMed

    Chitra, P Swathi; Swathi, T; Sahay, Rakesh; Reddy, G Bhanuprakash; Menon, Ram K; Kumar, P Anil

    2015-09-01

    The glomerular podocytes form a major size selective barrier for the filtration of serum proteins and reduced podocyte number is a critical event in the pathogenesis of proteinuria during diabetic nephropathy (DN). An elevated level of growth hormone (GH) is implicated as a causative factor in the development of nephropathy in patients with type 1 diabetes mellitus. We have previously shown that podocytes express GH receptor and are a target for GH action. To elucidate the molecular basis for the effects of GH on podocyte depletion, we conducted PCR-array analyses for extracellular matrix and adhesion molecules in podocytes. Our studies reveal that GH increases expression of a gene that encodes transforming growth factor-beta-induced protein (TGFBIp) expression. Similarly, microarray data retrieved from the Nephromine database revealed elevation of TGFBIp in patients with DN. Treatment with GH results in increased secretion of extracellular TGFBIp by podocytes. Both GH and TGFBIp induced apoptosis and epithelial mesenchymal transition (EMT) of podocytes. Exposure of podocytes to GH and TGFBIp resulted in increased migration of cells and altered podocyte permeability to albumin across podocyte monolayer. Administration of GH to rats induced EMT and apoptosis in the glomerular fraction of the kidney. Therefore, we conclude that the GH-dependent increase in TGFBIp in the podocyte is one of the mechanisms responsible for podocyte depletion in DN.

  2. Albumin acts like transforming growth factor β1 in microbubble-based drug delivery.

    PubMed

    Chuang, Yueh-Hsun; Wang, Yu-Hsin; Chang, Tien-Kuei; Lin, Ching-Jung; Li, Pai-Chi

    2014-04-01

    Unlike lipid-shelled microbubbles (MBs), albumin-shelled microbubbles (MBs) have not been reported to be actively targeted to cells without the assistance of antibodies. Recent studies indicate that the albumin molecule is similar to transforming growth factor β (TGF-β) both structurally and functionally. The TGF-β superfamily is important during early tumor outgrowth, with an elevated TGF-β being tumor suppressive; at later stages, this switches to malignant conversion and progression, including breast cancer. TGF-β receptors I and II play crucial roles in both the binding and endocytosis of albumin. However, until now, no specific albumin receptor has been found. On the basis of the above-mentioned information, we hypothesized that non-antibody-conjugated albumin-shelled MBs can be used to deliver drugs to breast cancer cells. We also studied the possible roles of TGF-β1 and radiation force in the behavior of cells and albumin-shelled MBs. The results indicate that albumin-shelled MBs loaded with paclitaxel (PTX) induce breast cancer cell apoptosis without the specific targeting produced by an antibody. Applying either an acoustic radiation force or cavitation alone to cells with PTX-loaded albumin MBs increased the apoptosis rate to 23.2% and 26.3% (p < 0.05), respectively. We also found that albumin-shelled MBs can enter MDA-MB-231 breast cancer cells and remain there for at least 24 h, even in the presence of PTX loading. Confocal micrographs revealed that 70.5% of the breast cancer cells took up albumin-shelled MBs spontaneously after 1 d of incubation. Applying an acoustic radiation force further increased the percentage to 91.9% in our experiments. However, this process could be blocked by TGF-β1, even with subsequent exposure to the radiation force. From these results, we conclude that TGF-β1 receptors are involved in the endocytotic process by which albumin-shelled MBs enter breast cancer cells. The acoustic radiation force increases the contact

  3. Fibroblast growth factor-2 promotes in vitro mitral valve interstitial cell repair through transforming growth factor-β/Smad signaling.

    PubMed

    Han, Li; Gotlieb, Avrum I

    2011-01-01

    Transforming growth factor (TGF)-β and fibroblast growth factor (FGF)-2 both promote repair in valve interstitial cell (VIC) injury models; however, the relationship between TGF-β and FGF-2 in wound repair are not well understood. VIC confluent monolayers were wounded by mechanical injury and incubated separately or in combination with FGF-2, neutralizing antibody to FGF-2, neutralizing antibody to TGF-β, and betaglycan antibody for 24 hours after wounding. Phosphorylated Smad2/3 (pSmad2/3) was localized at the wound edge (WE) and at the monolayer away from the WE. Down-regulation of pSmad2/3 protein expression via small-interfering RNA transfection was performed. The extent of wound closure was monitored for up to 96 hours. FGF-2 incubation resulted in a significant increase in nuclear pSmad2/3 staining at the WE. Neutralizing antibody to TGF-β alone or with FGF-2 present resulted in a similar significant decrease in pSmad2/3. Neutralizing antibody to FGF-2 alone or with FGF-2 present showed a similar significant decrease in pSmad2/3; however, significantly more staining was observed than treatment with neutralizing antibody to TGF-β. Incubation with betaglycan antibody inhibited FGF-2-mediated pSmad2/3 signaling. Wound closure corresponded with pSmad2/3 staining at the WE. Down-regulation of pSmad2/3 via small-interfering RNA transfection significantly reduced the extent to which FGF-2 promoted wound closure. Fibroblast growth factor-2 promotes in vitro VIC wound repair, at least in part, through the TGF-β/Smad2/3 signaling pathway.

  4. Protopanaxatirol type ginsenoside Re promotes cyclic growth of hair follicles via inhibiting transforming growth factor β signaling cascades.

    PubMed

    Li, Zheng; Ryu, Seung-Wook; Lee, Jungsul; Choi, Kyungsun; Kim, Sunchang; Choi, Chulhee

    2016-02-19

    Ginsenosides, the major bio-active ingredients included in Panax ginseng, have been known for the hair growth activity and used to treat patients who suffer from hair loss; however, the detailed mechanisms of this action are still largely unknown. This study was conducted to investigate the molecular and cellular mechanisms responsible for hair growth promoting effect of ginsenoside Re (GRe) in vitro and in vivo. Different doses of minoxidil and GRe were administered topically to the back regions of nude mice for up to 45 days, and hair shaft length and hair cycles were determined for hair promoting activities. Topical treatment of GRe significantly increased the hair shaft length and hair existent time, which was comparable to the action of minoxidil. We also demonstrated that GRe stimulated hair shaft elongation in the ex vivo cultures of vibrissa hair follicles isolated from C57BL/6 mouse. Systemic transcriptome analysis by next generation sequencing demonstrated that TGF-β-pathway related genes were selectively down-regulated by treatment of GRe in vivo, and the same treatment suppressed TGF-β-induced phosphorylation of ERK in HeLa cells. The results clearly indicated that GRe is the effective constituent in the ginseng on hair promotion via selective inhibition of the hair growth phase transition related signaling pathways, TGF-β signaling cascades.

  5. Basins beyond Bends along Continental Transforms in NW Turkey and Southern California: Rapid, Asymmetric, and Time-Transgressive Growth

    NASA Astrophysics Data System (ADS)

    Seeber, L.; Shillington, D. J.; Cifci, G.; Demirbag, E.; Sorlien, C. C.; Steckler, M. S.

    2009-12-01

    Basins along transcurrent faults have long been of interest as petroleum reservoirs and as markers of transform tectonics. We investigate a class of basins that develop on the transtensional side of fault bends, based on examples along two well-known continental transforms. The Tekirdag (western) and the Cinarcik (eastern) basins in the Marmara Sea are similar active structures on the ‘downstream’ side of prominent bends along the North Anatolian fault (NAF). Much has been learned about these structures from submarine exploration in the Marmara Sea following the disastrous 1999 earthquakes on the NAF. The Ridge Basin along the San Andreas fault system in southern California exhibits similar features, despite being an exhumed Miocene structure viewed from a different perspective. The comparison points to signature characteristics of a type basin associated with transform bends and helps in developing hypotheses about the 3D development of these basins. The basins are asymmetric in two ways. They are half grabens bordered by the transform and are tilting progressively toward it. This fault is dipping toward the basin and is slipping obliquely, accommodating both transcurrence and extension. In addition, these basins are tilting toward the bend on the fault, which is ‘upstream’ from the basin, considering the motion of the side of the fault where the basin is forming relative to the other side. As a result, the most rapid subsidence is near the fault and near the bend. But, the fastest subsidence and the deepest part are at opposite ends of these basins and keep getting further apart, because their growths are time-transgressive. This key feature stems from the asymmetry, which is not just geometric, but also kinematic. The basin and the deformation that accommodates the fault bend are confined to one side of the fault. This implies that the bend is fixed on the other side. The basin-side of the fault ‘flows’ over the bend and, like water in a stream

  6. The transforming growth factor beta type II receptor can replace the activin type II receptor in inducing mesoderm.

    PubMed Central

    Bhushan, A; Lin, H Y; Lodish, H F; Kintner, C R

    1994-01-01

    The type II receptors for the polypeptide growth factors transforming growth factor beta (TGF-beta) and activin belong to a new family of predicted serine/threonine protein kinases. In Xenopus embryos, the biological effects of activin and TGF-beta 1 are strikingly different; activin induces a full range of mesodermal cell types in the animal cap assay, while TGF-beta 1 has no effects, presumably because of the lack of functional TGF-beta receptors. In order to assess the biological activities of exogenously added TGF-beta 1, RNA encoding the TGF-beta type II receptor was introduced into Xenopus embryos. In animal caps from these embryos, TGF-beta 1 and activin show similar potencies for induction of mesoderm-specific mRNAs, and both elicit the same types of mesodermal tissues. In addition, the response of animal caps to TGF-beta 1, as well as to activin, is blocked by a dominant inhibitory ras mutant, p21(Asn-17)Ha-ras. These results indicate that the activin and TGF-beta type II receptors can couple to similar signalling pathways and that the biological specificities of these growth factors lie in their different ligand-binding domains and in different competences of the responding cells. Images PMID:8196664

  7. Tumor Suppressor Bromodomain-containing Protein 7 Cooperates with Smads to Promote Transforming Growth Factor-β Responses

    PubMed Central

    Liu, Jinquan; He, Zhou; Zhang, Ye; You, Han; Huang, Jun; Lin, Xia; Feng, Xin-Hua

    2016-01-01

    Smad proteins are central mediators in the canonical transforming growth factor-β (TGF-β) signaling pathway in mammalian cells. We report here that bromodomain-containing protein 7 (BRD7) functions as a novel transcription coactivator for Smads in TGF-β signaling. BRD7 forms a TGF-β inducible complex with Smad3/4 through its N-terminal Smad-binding domain. BRD7 simultaneously binds to acetylated histones to promote Smad-chromatin association, and associates with histone acetyltransferase p300 to enhance Smad transcriptional activity. Ectopic expression of BRD7, but not its mutants defective in Smad binding, enhances TGF-β transcriptional, tumor suppressing and epithelial-mesenchymal transition (EMT) responses. Conversely, depletion of BRD7 inhibits TGF-β responses. Thus, our study provides compelling evidence for a new function of BRD7 in fine-tuning TGF-β physiological responses. PMID:27270427

  8. Transforming growth factor-beta, transforming growth factor-beta receptor II, and p27Kip1 expression in nontumorous and neoplastic human pituitaries.

    PubMed Central

    Jin, L.; Qian, X.; Kulig, E.; Sanno, N.; Scheithauer, B. W.; Kovacs, K.; Young, W. F.; Lloyd, R. V.

    1997-01-01

    Transforming growth factor (TGF)-beta has been implicated in the regulation of normal and neoplastic anterior pituitary cell function. TGF-beta regulates the expression of various proteins, including p27Kip1 (p27), a cell cycle inhibitory protein. We examined TGF-beta, TGF-beta type II receptor (TGF-beta-RII), and p27 expression in normal pituitaries, pituitary adenomas, and carcinomas to analyze the possible roles of these proteins in pituitary tumorigenesis. Normal pituitary, pituitary adenomas, and pituitary carcinomas all expressed TGF-beta and TGF-beta-RII immunoreactivity. Reverse transcription polymerase chain reaction analysis showed TGF-beta 1, -beta 2, and -beta 3 isoforms and TGF-beta-RII in normal pituitaries and pituitary adenomas. Pituitary adenomas cells cultured for 7 days in defined media showed a biphasic response to TGF-beta with significant inhibition of follicle-stimulating hormone secretion at higher concentrations (10(-9) mol/L) and stimulation of follicle-stimulating hormone secretion at lower concentrations (10(-13) mol/L) of TGF-beta 1 in gonadotroph adenomas. Immunohistochemical analysis for p27 protein expression showed the highest levels in nontumorous pituitaries with decreased immunoreactivity in adenomas and carcinomas. When nontumorous pituitaries and various adenomas were analyzed for p27 and specific hormone production, growth hormone, luteinizing hormone, and thyroid-stimulating hormone cells and tumors had the highest percentages of cells expressing p27, whereas adrenocorticotrophic hormone cells and tumors had the lowest percentages. Immunoblotting analysis showed that adrenocorticotrophic hormone adenomas also had the lowest levels of p27 protein. Semiquantitative reverse transcription polymerase chain reaction and Northern hybridization analysis did not show significant differences in p27 mRNA expression in the various types of adenomas or in nontumorous pituitaries. In situ hybridization for p27 mRNA showed similar

  9. Activation of H-ras oncogene in 3-methylcholanthrene-transformed human cell line.

    PubMed

    Rhim, J S; Fujita, J; Park, J B

    1987-08-01

    DNA prepared from the 3-methylcholanthrene (3MC)-transformed human 312H cell line induced foci on NIH/3T3 cells, whereas DNAs prepared from 7,12-dimethylbenz[a]-anthracene-transformed and the dimethylsulfoxide control 312H cell lines failed to induce foci. The transformed gene from the 3MC-transformed 312H cells was identified as an activated form of the human cellular transforming H-ras oncogene. Analysis of the ras oncogene p21 product in this transformant by immunoprecipitation and gel electrophoresis suggested that this gene was activated by mutation in the 61st codon. These findings demonstrate that activation of a member of the ras gene family can occur in a chemically transformed human cell line.

  10. De-ubiquitinating enzyme, USP11, promotes transforming growth factor β-1 signaling through stabilization of transforming growth factor β receptor II

    PubMed Central

    Jacko, A M; Nan, L; Li, S; Tan, J; Zhao, J; Kass, D J; Zhao, Y

    2016-01-01

    The transforming growth factor β-1 (TGFβ-1) signaling pathway plays a central role in the pathogenesis of pulmonary fibrosis. Two TGFβ-1 receptors, TβRI and TβRII, mediate this pathway. TβRI protein stability, as mediated by the ubiquitin/de-ubiquitination system, has been well studied; however, the molecular regulation of TβRII still remains unclear. Here we reveal that a de-ubiquitinating enzyme, USP11, promotes TGFβ-1 signaling through de-ubiquitination and stabilization of TβRII. We elucidate the role that mitoxantrone (MTX), an USP11 inhibitor, has in the attenuation of TGFβ-1 signaling. Inhibition or downregulation of USP11 results in increases in TβRII ubiquitination and reduction of TβRII stability. Subsequently, TGFβ-1 signaling is greatly attenuated, as shown by the decreases in phosphorylation of SMAD2/3 levels as well as that of fibronectin (FN) and smooth muscle actin (SMA). Overexpression of USP11 reduces TβRII ubiquitination and increases TβRII stabilization, thereby elevating phosphorylation of SMAD2/3 and the ultimate expression of FN and SMA. Further, elevated expression of USP11 and TβRII were detected in lung tissues from bleomycin-challenged mice and IPF patients. Therefore, USP11 may contribute to the pathogenesis of pulmonary fibrosis by stabilization of TβRII and promotion of TGFβ-1 signaling. This study provides mechanistic evidence for development of USP11 inhibitors as potential antifibrotic drugs for pulmonary fibrosis. PMID:27853171

  11. Inhibition of CD1d-mediated antigen presentation by the transforming growth factor-β/Smad signalling pathway.

    PubMed

    Bailey, Jennifer C; Iyer, Abhirami K; Renukaradhya, Gourapura J; Lin, Yinling; Nguyen, Hoa; Brutkiewicz, Randy R

    2014-12-01

    CD1d-mediated lipid antigen presentation activates a subset of innate immune lymphocytes called invariant natural killer T (NKT) cells that, by virtue of their potent cytokine production, bridge the innate and adaptive immune systems. Transforming growth factor (TGF-β) is a known immune modulator that can activate the mitogen-activated protein kinase p38; we have previously shown that p38 is a negative regulator of CD1d-mediated antigen presentation. Several studies implicate a role for TGF-β in the activation of p38. Therefore, we hypothesized that TGF-β would impair antigen presentation by CD1d. Indeed, a dose-dependent decrease in CD1d-mediated antigen presentation and impairment of lipid antigen processing was observed in response to TGF-β treatment. However, it was found that this inhibition was not through p38 activation. Instead, Smads 2, 3 and 4, downstream elements of the TGF-β canonical signalling pathway, contributed to the observed effects. In marked contrast to that observed with CD1d, TGF-β was found to enhance MHC class II-mediated antigen presentation. Overall, these results suggest that the canonical TGF-β/Smad pathway negatively regulates an important arm of the host's innate immune responses - CD1d-mediated lipid antigen presentation to NKT cells.

  12. Early stage reversed crystal growth of zeolite A and its phase transformation to sodalite.

    PubMed

    Greer, Heather; Wheatley, Paul S; Ashbrook, Sharon E; Morris, Russell E; Zhou, Wuzong

    2009-12-16

    Microstructural analysis of the early stage crystal growth of zeolite A in hydrothermal synthetic conditions revealed a revised crystal growth route from surface to core in the presence of the biopolymer chitosan. The mechanism of this extraordinary crystal growth route is discussed. In the first stage, the precursor and biopolymer aggregated into amorphous spherical particles. Crystallization occurred on the surface of these spheres, forming the typical cubic morphology associated with zeolite A with a very thin crystalline cubic shell and an amorphous core. With a surface-to-core extension of crystallization, sodalite nanoplates were crystallized within the amorphous cores of these zeolite A cubes, most likely due to an increase of pressure. These sodalite nanoplates increased in size, breaking the cubic shells of zeolite A in the process, leading to the phase transformation from zeolite A to sodalite via an Ostwald ripening process. Characterization of specimens was performed using scanning electron microscopy and transmission electron microscopy, supported by other techniques including X-ray diffraction, solid-state NMR, and N(2) adsorption/desorption.

  13. Transforming growth factor-β1 induces EMT by the transactivation of epidermal growth factor signaling through HA/CD44 in lung and breast cancer cells

    PubMed Central

    LI, LINGMEI; QI, LISHA; LIANG, ZHIJIE; SONG, WANGZHAO; LIU, YANXUE; WANG, YALEI; SUN, BAOCUN; ZHANG, BIN; CAO, WENFENG

    2015-01-01

    Epithelial-mesenchymal transition (EMT), a process closely related to tumor development, is regulated by a variety of signaling pathways and growth factors, such as transforming growth factor-β1 (TGF-β1) and epidermal growth factor (EGF). Hyaluronan (HA) has been shown to induce EMT through either TGF-β1 or EGF signaling and to be a regulator of the crosstalk between these two pathways in fibroblasts. In this study, in order to clarify whether HA has the same effect in tumor cells, we utilized the lung cancer cell line, A549, and the breast cancer cell line, MCF-7, and found that the effects of stimulation with TGF-β1 were more potent than those of EGF in regulating the expression of EMT-associated proteins and in enhancing cell migration and invasion. In addition, we observed that TGF-β1 activated EGF receptor (EGFR) and its downstream AKT and extracellular signal-regulated kinase (ERK) pathways. Furthermore, we found that TGF-β1 upregulated the expression of hyaluronan synthases (HAS1, HAS2 and HAS3) and promoted the expression of CD44, a cell surface receptor for HA, which interacts with EGFR, resulting in the activation of the downstream AKT and ERK pathways. Conversely, treatment with 4-methylumbelliferone (4-MU; an inhibitor of HAS) prior to stimulation with TGF-β1, inhibited the expression of CD44 and EGFR, abolished the interaction between CD44 and EGFR. Furthermore, the use of shRNA targeting CD44 impaired the expression of EGFR, deactivated the AKT and ERK pathways, reversed EMT and decreased the migration and invasion ability of cells. In conclusion, our data demonstrate that TGF-β1 induces EMT by the transactivation of EGF signaling through HA/CD44 in lung and breast cancer cells. PMID:26005723

  14. Inhibition of endogenous heat shock protein 70 attenuates inducible nitric oxide synthase induction via disruption of heat shock protein 70/Na(+) /H(+) exchanger 1-Ca(2+) -calcium-calmodulin-dependent protein kinase II/transforming growth factor β-activated kinase 1-nuclear factor-κB signals in BV-2 microglia.

    PubMed

    Huang, Chao; Lu, Xu; Wang, Jia; Tong, Lijuan; Jiang, Bo; Zhang, Wei

    2015-08-01

    Inducible nitric oxide synthase (iNOS) critically contributes to inflammation and host defense. The inhibition of heat shock protein 70 (Hsp70) prevents iNOS induction in lipopolysaccharide (LPS)-stimulated macrophages. However, the role and mechanism of endogenous Hsp70 in iNOS induction in microglia remains unclear. This study addresses this issue in BV-2 microglia, showing that Hsp70 inhibition or knockdown prevents LPS-induced iNOS protein expression and nitric oxide production. Real-time PCR experiments showed that LPS-induced iNOS mRNA transcription was blocked by Hsp70 inhibition. Further studies revealed that the inhibition of Hsp70 attenuated LPS-stimulated nuclear translocation and phosphorylation of nuclear factor (NF)-κB as well as the degradation of inhibitor of κB (IκB)-α and phosphorylation of IκB kinase β (IKKβ). This prevention effect of Hsp70 inhibition on IKKβ-NF-κB activation was found to be dependent on the Ca(2+) /calcium-calmodulin-dependent protein kinase II (CaMKII)/transforming growth factor β-activated kinase 1 (TAK1) signals based on the following observations: 1) chelation of intracellular Ca(2+) or inhibition of CaMKII reduced LPS-induced increases in TAK1 phosphorylation and 2) Hsp70 inhibition reduced LPS-induced increases in CaMKII/TAK1 phosphorylation, intracellular pH value, [Ca(2+) ]i , and CaMKII/TAK1 association. Mechanistic studies showed that Hsp70 inhibition disrupted the association between Hsp70 and Na(+) /H(+) exchanger 1 (NHE1), which is an important exchanger responsible for Ca(2+) influx in LPS-stimulated cells. These studies demonstrate that the inhibition of endogenous Hsp70 attenuates the induction of iNOS, which likely occurs through the disruption of NHE1/Hsp70-Ca(2+) -CaMKII/TAK1-NF-κB signals in BV-2 microglia, providing further insight into the functions of Hsp70 in the CNS.

  15. Pleiotropic effects of transforming growth factor-β in hematopoietic stem-cell transplantation.

    PubMed

    Coomes, Stephanie M; Moore, Bethany B

    2010-12-15

    Transforming growth factor (TGF)-β is a pleiotropic cytokine with beneficial and detrimental effects posthematopoietic stem-cell transplantation. TGF-β is increased in specific sites postengraftment and can suppress immune responses and maintain peripheral tolerance. Thus, TGF-β may promote allograft acceptance. However, TGF-β is also the central pathogenic cytokine in fibrotic disease and likely promotes pneumonitis. Although TGF-β can enhance leukocyte recruitment and IgA production, it inhibits both innate and adaptive immune cell function and antiviral host defense posthematopoietic stem-cell transplantation. This review will focus on the current understanding of TGF-β biology and the numerous ways it can impact outcomes posttransplant.

  16. Connective Tissue Disorders and Cardiovascular Complications: The indomitable role of Transforming Growth Factor-beta signaling

    PubMed Central

    Wheeler, Jason B.; Ikonomidis, John S.; Jones, Jeffrey A.

    2015-01-01

    Marfan Syndrome (MFS) and Loeys-Dietz Syndrome (LDS) represent heritable connective tissue disorders that cosegregate with a similar pattern of cardiovascular defects (thoracic aortic aneurysm, mitral valve prolapse/regurgitation, and aortic dilatation with regurgitation). This pattern of cardiovascular defects appears to be expressed along a spectrum of severity in many heritable connective tissue disorders and raises suspicion of a relationship between the normal development of connective tissues and the cardiovascular system. Given the evidence of increased transforming growth factor-beta (TGF-β) signaling in MFS and LDS, this signaling pathway may represent the common link in this relationship. To further explore this hypothetical link, this chapter will review the TGF-β signaling pathway, heritable connective tissue syndromes related to TGF-β receptor (TGFBR) mutations, and discuss the pathogenic contribution of TGF-β to these syndromes with a primary focus on the cardiovascular system. PMID:24443024

  17. Transforming growth factor Beta-releasing scaffolds for cartilage tissue engineering.

    PubMed

    Madry, Henning; Rey-Rico, Ana; Venkatesan, Jagadeesh K; Johnstone, Brian; Cucchiarini, Magali

    2014-04-01

    The maintenance of a critical threshold concentration of transforming growth factor beta (TGF-β) for a given period of time is crucial for the onset and maintenance of chondrogenesis. Thus, the development of scaffolds that provide temporal and/or spatial control of TGF-β bioavailability has appeal as a mechanism to induce the chondrogenesis of stem cells in vitro and in vivo for articular cartilage repair. In the past decade, many types of scaffolds have been designed to advance this goal: hydrogels based on polysaccharides, hyaluronic acid, and alginate; protein-based hydrogels such as fibrin, gelatin, and collagens; biopolymeric gels and synthetic polymers; and solid and hybrid composite (hydrogel/solid) scaffolds. In this study, we review the progress in developing strategies to deliver TGF-β from scaffolds with the aim of enhancing chondrogenesis. In the future, such scaffolds could prove critical for tissue engineering cartilage, both in vitro and in vivo.

  18. MicroRNAs, transforming growth factor beta-1, and tissue fibrosis.

    PubMed

    Bowen, Timothy; Jenkins, Robert H; Fraser, Donald J

    2013-01-01

    MicroRNAs are short noncoding RNA regulators that repress synthesis of their targets post-transcriptionally. On average, each microRNA is estimated to regulate several hundred protein-coding genes, and about 60% of proteins are thought to be regulated by microRNAs in total. A subset of these genes, including the key profibrotic cytokine transforming growth factor beta-1 (TGF-β1), exhibits particularly strong levels of post-transcriptional control of protein synthesis, involving microRNAs and other mechanisms. Changes in microRNA expression pattern are linked to profound effects on cell phenotype, and microRNAs have an emerging role in diverse physiological and pathological processes. In this review, we provide an overview of microRNA biology with a focus on their emerging role in diseases typified by organ fibrosis.

  19. Transforming growth factor-β1 in the cerebrospinal fluid of patients with distinct neurodegenerative diseases.

    PubMed

    Masuda, Tomoyuki; Itoh, Junko; Koide, Takuya; Tomidokoro, Yasushi; Takei, Yosuke; Ishii, Kazuhiro; Tamaoka, Akira

    2017-01-01

    A chronic inflammatory condition may underlie neurodegenerative disorders, including Parkinson's disease (PD) and Alzheimer's disease (AD). For example, both PD and AD patients show an increase in transforming growth factor-β1 (TGF-β1) levels in their cerebrospinal fluid (CSF). TGF-β1 is a cytokine that inhibits inflammation. In the present study, using an enzyme-linked immunosorbent assay, we tested the hypothesis that the level of TGF-β1 in the CSF of patients with amyotrophic lateral sclerosis (ALS), spinocerebellar degeneration (SCD), or multiple system atrophy-cerebellar subtype (MSA-C) would be elevated compared with that of normal controls. We found that TGF-β1 levels in the CSF were not significantly different between these patients and normal controls. Our data suggest that the level of TGF-β1 in the CSF is an unreliable biomarker of ALS, SCD, and MSA-C.

  20. The pleiotropic roles of transforming growth factor beta inhomeostasis and carcinogenesis of endocrine organs.

    SciTech Connect

    Fleisch, Markus C.; Maxwell, Christopher A.; Barcellos-Hoff,Mary-Helen

    2006-01-13

    Transforming growth factor beta (TGF-beta) is a ubiquitous cytokine that plays a critical role in numerous pathways regulating cellular and tissue homeostasis. TGF-beta is regulated by hormones and is a primary mediator of hormone response in uterus, prostate and mammary gland. This review will address the role of TGF-beta in regulating hormone dependent proliferation and morphogenesis. The subversion of TGF-beta regulation during the processes of carcinogenesis, with particular emphasis on its effects on genetic stability and epithelial to mesenchymal transition (EMT), will also be examined. An understanding of the multiple and complex mechanisms of TGF-beta regulation of epithelial function, and the ultimate loss of TGF-beta function during carcinogenesis, will be critical in the design of novel therapeutic interventions for endocrine-related cancers.

  1. Transforming growth factor-β: an important mediator in Helicobacter pylori-associated pathogenesis

    PubMed Central

    Li, Nianshuang; Xie, Chuan; Lu, Nong-Hua

    2015-01-01

    Helicobacter pylori (H.pylori) is a Gram-negative, microaerophilic, helical bacillus that specifically colonizes the gastric mucosa. The interaction of virulence factors, host genetic factors, and environmental factors contributes to the pathogenesis of H. pylori-associated conditions, such as atrophic gastritis and intestinal metaplasia. Infection with H. pylori has recently been recognized as the strongest risk factor for gastric cancer. As a pleiotropic cytokine, transforming growth factor (TGF)-β regulates various biological processes, including cell cycle, proliferation, apoptosis, and metastasis. Recent studies have shed new light on the involvement of TGF-β signaling in the pathogenesis of H. pylori infection. This review focuses on the potential etiological roles of TGF-β in H. pylori-mediated gastric pathogenesis. PMID:26583078

  2. The Role of Transforming Growth Factor β1 in the Regulation of Blood Pressure

    PubMed Central

    Matsuki, Kota; Hathaway, Catherine K.; Lawrence, Marlon G.; Smithies, Oliver; Kakoki, Masao

    2016-01-01

    Although human association studies suggest a link between polymorphisms in the gene encoding transforming growth factor (TGF) β1 and differing blood pressure levels, a causative mechanism for this correlation remains elusive. Recently we have generated a series of mice with graded expression of TGFβ1, ranging from approximately 10% to 300% compared to normal. We have found that blood pressure and plasma volume are negatively regulated by TGFβ1. Of note, the 10% hypomorph exhibits primary aldosteronism and markedly impaired urinary excretion of water and electrolytes. We here review previous literature highlighting the importance of TGFβ signaling as a natriuretic system, which we postulate is a causative mechanism explaining how polymorphisms in TGFβ1 could influence blood pressure levels. PMID:25801626

  3. Phosphorylation of the human-transforming-growth-factor-beta-binding protein endoglin.

    PubMed Central

    Lastres, P; Martín-Perez, J; Langa, C; Bernabéu, C

    1994-01-01

    Endoglin is an homodimeric membrane antigen with capacity to bind transforming growth factor-beta (TGF-beta). Phosphorylation of human endoglin was demonstrated in endothelial cells as well as in mouse fibroblast transfectants expressing two isoforms, L-endoglin or S-endoglin, with distinct cytoplasmic domains. The extent of L-endoglin phosphorylation was found to be 8-fold higher than that of S-endoglin, and phosphopeptide analyses revealed at least three different phosphorylation sites for L-endoglin, whereas S-endoglin produces only one phosphopeptide. The immunoprecipitated L-endoglin was found to be phosphorylated mainly on serine, and, to a minor extent, on threonine, residues. Treatment of the cells with TGF-beta 1 or the protein kinase C inhibitor H-7 resulted in a reduction of the levels of endoglin phosphorylation. Images Figure 1 Figure 2 PMID:8053900

  4. Dissolution and transformation of cerium oxide nanoparticles in plant growth media

    NASA Astrophysics Data System (ADS)

    Schwabe, Franziska; Schulin, Rainer; Rupper, Patrick; Rotzetter, Aline; Stark, Wendelin; Nowack, Bernd

    2014-10-01

    From environmental modeling of engineered nanomaterial (ENM) release, it is clear that ENMs will enter soils, where they interact with soil compounds as well as plant roots. We analyzed three different size groups of cerium dioxide nanoparticles (CeO2-NPs) in respect to chemical changes in the most common plant growth medium, Hoagland solution. We created a simple environmental model using liquid dispersions of 9-, 23-, and 64-nm-uncoated CeO2-NPs. We found that CeO2-NPs release dissolved Ce when the pH of the medium is below 4.6 and in the presence of strong chelating agents even at pH of 8. In addition, we found that in reaction with Fe2+-ions, equimolar amounts of Ce were released from NPs. We could elucidate the involvement of the CeO2-NPs surface redox cycle between Ce3+ and Ce4+ to explain particle transformation. The chemical transformation of CeO2-NPs was summarized in four probable reactions: dissolution, surface reduction, complexation, and precipitation on the NP surface. The results show that CeO2-NPs are clearly not insoluble as often stated but can release significant amounts of Ce depending on the composition of the surrounding medium.

  5. Transforming growth factor-β1 and cigarette smoke inhibit the ability of β2-agonists to enhance epithelial permeability.

    PubMed

    Unwalla, Hoshang J; Ivonnet, Pedro; Dennis, John S; Conner, Gregory E; Salathe, Matthias

    2015-01-01

    Chronic bronchitis, caused by cigarette smoke exposure, is characterized by mucus hypersecretion and reduced mucociliary clearance (MCC). Effective MCC depends, in part, on adequate airway surface liquid. Cystic fibrosis transmembrane conductance regulator (CFTR) provides the necessary osmotic gradient for serosal to mucosal fluid transport through its ability to both secrete Cl(-) and regulate paracellular permeability, but CFTR activity is attenuated in chronic bronchitis and in smokers. β2-adrenergic receptor (β2-AR) agonists are widely used for managing chronic obstructive pulmonary disease, and can activate CFTR, stimulate ciliary beat frequency, and increase epithelial permeability, thereby stimulating MCC. Patients with chronic airway diseases and cigarette smokers demonstrate increased transforming growth factor (TGF)-β1 signaling, which suppresses β2-agonist-mediated CFTR activation and epithelial permeability increases. Restoring CFTR function in these diseases can restore the ability of β2-agonists to enhance epithelial permeability. Human bronchial epithelial cells, fully redifferentiated at the air-liquid interface, were used for (14)C mannitol flux measurements, Ussing chamber experiments, and quantitative RT-PCR. β2-agonists enhance epithelial permeability by activating CFTR via the β2-AR/adenylyl cyclase/cAMP/protein kinase A pathway. TGF-β1 inhibits β2-agonist-mediated CFTR activation and epithelial permeability enhancement. Although TGF-β1 down-regulates both β2-AR and CFTR mRNA, functionally it only decreases CFTR activity. Cigarette smoke exposure inhibits β2-agonist-mediated epithelial permeability increases, an effect reversed by blocking TGF-β signaling. β2-agonists enhance epithelial permeability via CFTR activation. TGF-β1 signaling inhibits β2-agonist-mediated CFTR activation and subsequent increased epithelial permeability, potentially limiting the ability of β2-agonists to facilitate paracellular transport in disease

  6. Transforming Growth Factor-β1 and Cigarette Smoke Inhibit the Ability of β2-Agonists to Enhance Epithelial Permeability

    PubMed Central

    Ivonnet, Pedro; Dennis, John S.; Conner, Gregory E.; Salathe, Matthias

    2015-01-01

    Chronic bronchitis, caused by cigarette smoke exposure, is characterized by mucus hypersecretion and reduced mucociliary clearance (MCC). Effective MCC depends, in part, on adequate airway surface liquid. Cystic fibrosis transmembrane conductance regulator (CFTR) provides the necessary osmotic gradient for serosal to mucosal fluid transport through its ability to both secrete Cl− and regulate paracellular permeability, but CFTR activity is attenuated in chronic bronchitis and in smokers. β2-adrenergic receptor (β2-AR) agonists are widely used for managing chronic obstructive pulmonary disease, and can activate CFTR, stimulate ciliary beat frequency, and increase epithelial permeability, thereby stimulating MCC. Patients with chronic airway diseases and cigarette smokers demonstrate increased transforming growth factor (TGF)-β1 signaling, which suppresses β2-agonist–mediated CFTR activation and epithelial permeability increases. Restoring CFTR function in these diseases can restore the ability of β2-agonists to enhance epithelial permeability. Human bronchial epithelial cells, fully redifferentiated at the air–liquid interface, were used for 14C mannitol flux measurements, Ussing chamber experiments, and quantitative RT-PCR. β2-agonists enhance epithelial permeability by activating CFTR via the β2-AR/adenylyl cyclase/cAMP/protein kinase A pathway. TGF-β1 inhibits β2-agonist–mediated CFTR activation and epithelial permeability enhancement. Although TGF-β1 down-regulates both β2-AR and CFTR mRNA, functionally it only decreases CFTR activity. Cigarette smoke exposure inhibits β2-agonist–mediated epithelial permeability increases, an effect reversed by blocking TGF-β signaling. β2-agonists enhance epithelial permeability via CFTR activation. TGF-β1 signaling inhibits β2-agonist–mediated CFTR activation and subsequent increased epithelial permeability, potentially limiting the ability of β2-agonists to facilitate paracellular transport in

  7. Astrocyte-derived growth factors and estrogen neuroprotection: role of transforming growth factor-α in estrogen-induced upregulation of glutamate transporters in astrocytes.

    PubMed

    Karki, Pratap; Smith, Keisha; Johnson, James; Lee, Eunsook

    2014-05-25

    Extensive studies from the past decade have completely revolutionized our understanding about the role of astrocytes in the brain from merely supportive cells to an active role in various physiological functions including synaptic transmission via cross-talk with neurons and neuroprotection via releasing neurotrophic factors. Particularly, numerous studies have reported that astrocytes mediate the neuroprotective effects of 17β-estradiol (E2) and selective estrogen receptor modulators (SERMs) in various clinical and experimental models of neuronal injury. Astrocytes contain two main glutamate transporters, glutamate aspartate transporter (GLAST) and glutamate transporter-1 (GLT-1), that play a key role in preventing excitotoxic neuronal death, a process associated with most neurodegenerative diseases. E2 has been shown to increase expression of both GLAST and GLT-1 mRNA and protein and glutamate uptake in astrocytes. Growth factors such as transforming growth factor-α (TGF-α) appear to mediate E2-induced enhancement of these transporters. These findings suggest that E2 exerts neuroprotection against excitotoxic neuronal injuries, at least in part, by enhancing astrocytic glutamate transporter levels and function. Therefore, the present review will discuss proposed mechanisms involved in astrocyte-mediated E2 neuroprotection, with a focus on glutamate transporters.

  8. Interactions between stromal cell--derived keratinocyte growth factor and epithelial transforming growth factor in immune-mediated crypt cell hyperplasia.

    PubMed Central

    Bajaj-Elliott, M; Poulsom, R; Pender, S L; Wathen, N C; MacDonald, T T

    1998-01-01

    Immune reactions in the gut are associated with increased epithelial cell proliferation. Here we have studied the role of keratinocyte growth factor (KGF; FGF7) and transforming growth factor-alpha (TGF-alpha) in the epithelial cell hyperplasia seen in explants of fetal human small intestine after activation of lamina propria T cells with the superantigen Staphylococcus aureus enterotoxin B (SEB). After the addition of SEB to the explants there is a 10-fold increase in KGF mRNA by 72 h of culture. KGF transcripts were abundant in the lamina propria using in situ hybridization and the culture supernatants contained elevated amounts of KGF protein. SEB had no direct effect on KGF mRNA and protein production by cultured lamina propria mesenchymal cells, but both were upregulated by TNF-alpha. Accompanying the increase in KGF there was also an increase in TGF-alpha precursor proteins in the culture supernatants and the phosphorylated form of the EGFR receptor was also detected in the tissue. Increased TGF-alpha precursor proteins were also detected in the supernatants of control explants stimulated with KGF alone. The direct addition of KGF and TGF-alpha enhanced epithelial cell proliferation and antibodies against KGF and TGF-alpha partially inhibited SEB-induced crypt hyperplasia. These results suggest molecular cross-talk between the KGF/KGFR and the TGF-alpha/EGFR in immune-mediated crypt cell hyperplasia. PMID:9788959

  9. Abietane diterpenoids from Salvia sclarea transformed roots as growth inhibitors of pathogenic Acanthamoeba spp.

    PubMed

    Kuźma, Łukasz; Derda, Monika; Hadaś, Edward; Wysokińska, Halina

    2015-01-01

    Amoebae from the genus Acanthamoeba are known agents leading to various diseases such as granulomatous amoebic encephalitis (GAE), a chronic progressive disease of the central nervous system, amoebic keratitis (AK), chronic eye infection, amoebic pneumitis (AP), chronic lung infection, and skin infections. It is known that various synthetic anti-Acanthamoeba substances are ineffective. Therefore, other substances, e.g., natural plant compounds, are the focus of biological investigations regarding anti-parasite activity. In this work, the ability of four abietane diterpenoids (ferruginol, salvipisone, aethiopinone, and 1-oxo-aethiopinone) to inhibit Acanthamoeba growth is reported. All investigated compounds were active against Acanthamoeba growing in vitro. Among them, ferruginol demonstrated the highest activity against Acanthamoeba. This compound inhibited Acanthamoeba growth by about 72% in a 3-day exposure period (IC50 17.45 μM), while aethiopinone and 1-oxo-aethiopinone demonstrated this activity at the level of 55-56%. Salvipisone reduced the growth of Acanthamoeba in vitro culture by 39%. For this compound, the value of IC50 was 701.94 μM after 72 h of exposure.

  10. Regulation of proliferation of embryonic heart mesenchyme: Role of transforming growth factor-beta 1 and the interstitial matrix

    SciTech Connect

    Choy, M.; Armstrong, M.T.; Armstrong, P.B. )

    1990-10-01

    Proliferation of atrioventricular cushion mesenchyme of the embryonic avian heart maintained in three-dimensional aggregate culture is stimulated by interaction with the interstitial matrix. Chicken serum or transforming growth factor-beta 1, which stimulates proliferation, induces matrix deposition in regions of the aggregate showing high labeling indices with tritiated thymidine. Dispersed heart mesenchyme interstitial matrix introduced into serum-free culture is incorporated into the aggregate and stimulates cellular proliferation similar to serum or transforming growth factor-beta 1. Proliferation is reversibly inhibited by the peptide Gly-Arg-Gly-Asp-Ser-Pro. It is suggested that transforming growth factor-beta 1 stimulates the production of interstitial matrix and that a sufficient stimulus for proliferation in this system is the presence of the matrix, which acts as the adhesive support for cellular anchorage.

  11. Cementogenesis and the induction of periodontal tissue regeneration by the osteogenic proteins of the transforming growth factor-beta superfamily.

    PubMed

    Ripamonti, U; Petit, J-C; Teare, J

    2009-04-01

    The antiquity and severity of periodontal diseases are demonstrated by the hard evidence of alveolar bone loss in gnathic remains of the Pliocene/Pleistocene deposits of the Bloubank Valley at Sterkfontein, Swartkrans and Kromdrai in South Africa. Extant Homo has characterized and cloned a superfamily of proteins which include the bone morphogenetic proteins that regulate tooth morphogenesis at different stages of development as temporally and spatially connected events. The induction of cementogenesis, periodontal ligament and alveolar bone regeneration are regulated by the co-ordinated expression of bone morphogenetic proteins. Naturally derived and recombinant human bone morphogenetic proteins induce periodontal tissue regeneration in mammals. Morphological analyses on undecalcified sections cut at 3-6 mum on a series of mandibular molar Class II and III furcation defects induced in the non-human primate Papio ursinus show the induction of cementogenesis. Sharpey's fibers nucleate as a series of composite collagen bundles within the cementoid matrix in close relation to embedded cementocytes. Osteogenic protein-1 and bone morphogenetic protein-2 possess a structure-activity profile, as shown by the morphology of tissue regeneration, preferentially cementogenic and osteogenic, respectively. In Papio ursinus, transforming growth factor-beta(3) also induces cementogenesis, with Sharpey's fibers inserting into newly formed alveolar bone. Capillary sprouting and invasion determine the sequential insertion and alignment of individual collagenic bundles. The addition of responding stem cells prepared by finely mincing fragments of autogenous rectus abdominis muscle significantly enhances the induction of periodontal tissue regeneration when combined with transforming growth factor-beta(3) implanted in Class II and III furcation defects of Papio ursinus.

  12. Inhibition of Transforming Growth Factor-{beta} Signaling in Normal Lung Epithelial Cells Confers Resistance to Ionizing Radiation

    SciTech Connect

    Reeves, Anna; Zagurovskaya, Marianna; Gupta, Seema; Shareef, Mohammed M.; Mohiuddin, Mohammed; Ahmed, Mansoor M. . E-mail: mmahmed@geisinger.edu

    2007-05-01

    Purpose: To address the functional role of radiation-induced transforming growth factor-{beta} (TGF-{beta}) signaling in a normal epithelial background, we selected a spontaneously immortalized lung epithelial cell line derived from the normal lung tissue of a dominant-negative mutant of the TGF-{beta} RII ({delta}RII) transgenic mouse that conditionally expressed {delta}RII under the control of the metallothionein promoter (MT-1), and assessed this cell line's response to radiation. Methods and Materials: A spontaneously immortalized lung epithelial cell culture (SILECC) was established and all analyses were performed within 50 passages. Colony-forming and terminal transferase dUPT nick end labeling (TUNEL) assays were used to assess clonogenic inhibition and apoptosis, respectively. Western-blot analysis was performed to assess the kinetics of p21, bax, and RII proteins. Transforming growth factor-{beta}-responsive promoter activity was measured using dual-luciferase reporter assay. Results: Exposure to ZnSO{sub 4} inhibited TGF-{beta} signaling induced either by recombinant TGF-{beta}1 or ionizing radiation. The SILECC, treated with either ZnSO{sub 4} or neutralizing antibody against TGF-{beta}, showed a significant increase in radio-resistance compared to untreated cells. Furthermore, the expression of {delta}RII inhibited the radiation-induced up-regulation of the TGF-{beta} effector gene p21{sup waf1/cip1}. Conclusions: Our findings imply that inhibition of radiation-induced TGF-{beta} signaling via abrogation of the RII function enhances the radio-resistance of normal lung epithelial cells, and this can be directly attributed to the loss of TGF-{beta} signaling function.

  13. Anti-oncogenic activity of signalling-defective epidermal growth factor receptor mutants.

    PubMed Central

    Redemann, N; Holzmann, B; von Rüden, T; Wagner, E F; Schlessinger, J; Ullrich, A

    1992-01-01

    Overexpression and autocrine activation of the epidermal growth factor receptor (EGF-R) cause transformation of cultured cells and correlate with tumor progression in cancer patients. Dimerization and transphosphorylation are crucial events in the process by which receptors with tyrosine kinase activity generate normal and transforming cellular signals. Interruption of this process by inactive receptor mutants offers the potential to inhibit ligand-induced cellular responses. Using recombinant retroviruses, we have examined the effects of signalling-incompetent EGF-R mutants on the growth-promoting and transforming potential of ligand-activated, overexpressed wild-type EGF-R and the v-erbB oncogene product. Expression of a soluble extracellular EGF-R domain had little if any effect on the growth and transformation of NIH 3T3 cells by either tyrosine kinase. However, both a kinase-negative EGF-R point mutant (HERK721A) and an EGF-R lacking 533 C-terminal amino acids efficiently inhibited wild-type EGF-R-mediated, de novo DNA synthesis and cell transformation in a dose-dependent manner. Furthermore, coexpression with the v-erbBES4 oncogene product in NIH 3T3 cells resulted in transphosphorylation of the HERK721A mutant receptor and reduced soft-agar colony growth but had no effect in a focus formation assay. These results demonstrate that signalling-defective receptor tyrosine kinase mutants differentially interfere with oncogenic signals generated by either overexpressed EGF-R or the retroviral v-erbBES4 oncogene product. Images PMID:1346334

  14. Chemical transformations on botryane skeleton. Effect on the cytotoxic activity.

    PubMed

    Reino, José L; Durán-Patrón, Rosa; Segura, Inmaculada; Hernández-Galán, Rosario; Riese, Hans H; Collado, Isidro G

    2003-03-01

    Eighteen compounds with a botryane skeleton have been obtained through chemical transformations of various toxins from the fungus Botrytis cinerea. During the course of these transformations, the C-10 carbon of the botryane skeleton was found to exhibit an interesting high regioselectivity to oxidizing and reducing agents. In addition, the cytotoxicity of 27 botryane derivatives was determined in vitro against Hs578T, MDA-MB-231, HT-1080, U87-MG, IMR-90, and HUVEC cell lines. The results of this study confirm that the cytotoxicity of botrydial (1) and its derivatives is related to the presence of a 1,5-dialdehyde functionality.

  15. A Histologically Distinctive Interstitial Pneumonia Induced by Overexpression of the Interleukin 6, Transforming Growth Factor β1, or Platelet-Derived Growth Factor B Gene

    NASA Astrophysics Data System (ADS)

    Yoshida, Mitsuhiro; Sakuma, Junko; Hayashi, Seiji; Abe, Kin'ya; Saito, Izumu; Harada, Shizuko; Sakatani, Mitsunoir; Yamamoto, Satoru; Matsumoto, Norinao; Kaneda, Yasufumi; Kishmoto, Tadamitsu

    1995-10-01

    Interstitial pneumonia is characterized by alveolitis with resulting fibrosis of the interstitium. To determine the relevance of humoral factors in the pathogenesis of interstitial pneumonia, we introduced expression vectors into Wistar rats via the trachea to locally overexpress humoral factors in the lungs. Human interleukin (IL) 6 and IL-6 receptor genes induced lymphocytic alveolitis without marked fibroblast proliferation. In contrast, overexpression of human transforming growth factor β1 or human platelet-derived growth factor B gene induced only mild or apparent cellular infiltration in the alveoli, respectively. However, both factors induced significant proliferation of fibroblasts and deposition of collagen fibrils. These histopathologic changes induced by the transforming growth factor β1 and platelet-derived growth factor B gene are partly akin to those changes seen in lung tissues from patients with pulmonary fibrosis and markedly contrast with the changes induced by overexpression of the IL-6 and IL-6 receptor genes that mimics lymphocytic interstitial pneumonia.

  16. 2-(Allylthio)pyrazine, a cancer chemopreventive agent, inhibits liver fibrosis induced by dimethylnitrosamine in rats: role of inhibition of transforming growth factor-beta1 expression.

    PubMed

    Kang, K W; Ha, J R; Kim, C W; Kim, N D; Kim, S G

    2001-07-01

    Exposure to nitrosamines may be the occupational risk factor for liver cirrhosis. 2-(Allylthio)pyrazine, a chemopreventive agent, inhibits CYP2E1 and induces phase II enzymes. We examined the effects of 2-(allylthio)pyrazine on hepatic fibrosis, a prepathologic state of cirrhosis, and on the expression of transforming growth factor-beta1 induced by dimethylnitrosamine. Treatment of rats with dimethylnitrosamine for 4 weeks increased plasma alanine/aspartate amino-transferase and y-glutamyl transpeptidase activities, and bilirubin content, whereas the total plasma protein and albumin levels were decreased. 2-(Allylthio)pyrazine inhibited dimethylnitrosamine-induced increases in the enzyme activities and bilirubin, and restored the plasma protein and albumin contents. Masson's trichrome staining showed that dimethylnitrosamine induced liver fibrosis, the extent of which was reduced by 2-(allylthio)pyrazine treatments. Reverse transcription-polymerase chain reaction analysis revealed that 2-(allylthio)pyrazine inhibited production of transforming growth factor-beta1 mRNA by dimethylnitrosamine. These results demonstrated that 2-(allylthio)pyrazine might inhibit dimethylnitrosamine-induced liver fibrosis due to suppression of CYP2E1 expression and transforming growth factor-beta1 production.

  17. Transforming growth factor-{beta}2 enhances differentiation of cardiac myocytes from embryonic stem cells

    SciTech Connect

    Kumar, Dinender . E-mail: Dinender.Kumar@uvm.edu; Sun, Baiming

    2005-06-24

    Stem cell therapy holds great promise for the treatment of injured myocardium, but is challenged by a limited supply of appropriate cells. Three different isoforms of transforming growth factor-{beta} (TGF-{beta}) -{beta}1, -{beta}2, and -{beta}3 exhibit distinct regulatory effects on cell growth, differentiation, and migration during embryonic development. We compared the effects of these three different isoforms on cardiomyocyte differentiation from embryonic stem (ES) cells. In contrast to TGF-{beta}1, or -{beta}3, treatment of mouse ES cells with TGF-{beta}2 isoform significantly increased embryoid body (EB) proliferation as well as the extent of the EB outgrowth that beat rhythmically. At 17 days, 49% of the EBs treated with TGF-{beta}2 exhibited spontaneous beating compared with 15% in controls. Cardiac myocyte specific protein markers sarcomeric myosin and {alpha}-actin were demonstrated in beating EBs and cells isolated from EBs. In conclusion, TGF-{beta}2 but not TGF-{beta}1, or -{beta}3 promotes cardiac myocyte differentiation from ES cells.

  18. Characterization of latent transforming growth factor-beta 2 from monkey kidney cells.

    PubMed

    Lioubin, M N; Madisen, L; Roth, R A; Purchio, A F

    1991-05-01

    Serum-free medium conditioned by BSC-40 cells was analyzed for the presence of transforming growth factor-beta 2 (TGF beta 2)-related proteins. Western blot analysis was performed using site-specific antipeptide antibodies directed against the pro- and mature regions of the TGF beta 2 precursor. When conditioned medium was analyzed by polyacrylamide gel electrophoresis under reducing conditions, proteins with mol wt of 53 kDa (containing both mature and proregion sequences), 34-38 kDa (containing proregion sequences only), and 12 kDa (containing mature sequences) were detected. Under nonreducing conditions, complexes of 60- to 80-kDa, 160- to 200-kDa, as well as 24-kDa mature dimers were seen. Cleavage of mature TGF beta 2 from its precursor was inhibited by monensin and chloroquin, but not by ammonium chloride or methylamine. Two peaks of bioactivity were detected after fractionation on a TSK column corresponding to mol wt of 130 and 400 kDa. These peaks contained TGF beta 2 and pro-TGF beta 2 proteins. Partial purification of the 130-kDa complex followed by N-glyconase digestion indicated that the pro-TGF beta 2 proteins were glycosylated. These data demonstrate that BSC-40 cells secrete mature TGF beta 2 complexed with proregion-containing proteins and suggest that this association may contribute to the latency phenomena observed with respect to this growth regulator.

  19. Promotion of embryonic chick limb cartilage differentiation by transforming growth factor-beta.

    PubMed

    Kulyk, W M; Rodgers, B J; Greer, K; Kosher, R A

    1989-10-01

    This study represents a first step in investigating the possible involvement of transforming growth factor-beta (TGF-beta) in the regulation of embryonic chick limb cartilage differentiation. TGF-beta 1 and 2 (1-10 ng/ml) elicit a striking increase in the accumulation of Alcian blue, pH 1-positive cartilage matrix, and a corresponding twofold to threefold increase in the accumulation of 35S-sulfate- or 3H-glucosamine-labeled sulfated glycosaminoglycans (GAG) by high density micromass cultures prepared from the cells of whole stage 23/24 limb buds or the homogeneous population of chondrogenic precursor cells comprising the distal subridge mesenchyme of stage 25 wing buds. Moreover, TGF-beta causes a striking (threefold to sixfold) increase in the steady-state cytoplasmic levels of mRNAs for cartilage-characteristic type II collagen and the core protein of cartilage-specific proteoglycan. Only a brief (2 hr) exposure to TGF-beta at the initiation of culture is sufficient to stimulate chondrogenesis, indicating that the growth factor is acting at an early step in the process. Furthermore, TGF-beta promotes the formation of cartilage matrix and cartilage-specific gene expression in low density subconfluent spot cultures of limb mesenchymal cells, which are situations in which little, or no chondrogenic differentiation normally occurs. These results provide strong incentive for considering and further investigating the role of TGF-beta in the control of limb cartilage differentiation.

  20. Fibulin-2 is Essential for Angiotensin II-Induced Myocardial Fibrosis Mediated by Transforming Growth Factor (TGF)-β

    PubMed Central

    Khan, Shaukat A.; Dong, Hailong; Joyce, Jennifer; Sasaki, Takako; Chu, Mon-Li; Tsuda, Takeshi

    2016-01-01

    Fibrosis is an ominous pathological process in failing myocardium, but its pathogenesis is poorly understood. We recently reported that loss of an extracellular matrix (ECM) protein, fibulin-2, protected against ventricular dysfunction after myocardial infarction (MI) in association with absence of activation of transforming growth factor (TGF)-β signaling and suppressed up-regulation of ECM protein expression during myocardial remodeling. Here, we investigated a role of fibulin-2 in the development of myocardial hypertrophy and fibrosis induced by continuous pressor-dosage of Ang II infusion. Both wild type (WT) and fibulin-2 null (Fbln2KO) mice developed comparable hypertension and myocardial hypertrophy by Ang II infusion. However, myocardial fibrosis with significant up-regulation of collagen type I and III mRNA was only seen in WT but not in Fbln2KO mice.Transforming growth factor (TGF)-β1 mRNA and its downstream signal, Smad2, were significantly up-regulated in WT by Ang II, whereas there were no Ang II-induced changes in Flbn2KO, suggesting fibulin-2 is necessary for Ang II-induced TGF-β signaling that induces myocardial fibrosis. To test whether fibulin-2 is sufficient for Ang II-induced TGF-β up-regulation, isolated Flbn2KO cardiac fibroblasts were treated with Ang II after transfecting with fibulin-2 expression vector or pretreating with recombinant fibulin-2 protein. Ang II-induced TGF-β signaling in Fbln2KO cells was partially rescued by exogenous fibulin-2, suggesting that fibulin-2 is required and probably sufficient for Ang II-induced TGF-β activation. Smad2 phosphorylation was induced just by adding recombinant fibulin-2 to KO cells, suggesting that extracellular interaction between fibulin-2 and latent TGF-β triggered initial TGF-β activation. Our study indicates that Ang II cannot induce TGF-β activation without fibulin-2 and that fibulin-2 plays an essential role in Ang II-induced TGF-β signaling and subsequent myocardial fibrosis

  1. Role and mechanism of miR-222 in arsenic-transformed cells for inducing tumor growth.

    PubMed

    Wang, Min; Ge, Xin; Zheng, Jitai; Li, Dongmei; Liu, Xue; Wang, Lin; Jiang, Chengfei; Shi, Zhumei; Qin, Lianju; Liu, Jiayin; Yang, Hushan; Liu, Ling-Zhi; He, Jun; Zhen, Linlin; Jiang, Bing-Hua

    2016-04-05

    High levels of arsenic in drinking water, soil, and air are associated with the higher incidences of several kinds of cancers worldwide, but the mechanism is yet to be fully discovered. Recently, a number of evidences show that dysregulation of microRNAs (miRNAs) induces carcinogenesis. In this study, we found miR-222 was upregulated in arsenic-transformed human lung epithelial BEAS-2B cells (As-T cells). Anti-miR-222 inhibitor treatment decreased cell proliferation, migration, tube formation, and induced apoptosis. In addition, anti-miR-222 inhibitor expression decreased tumor growth in vivo. We also found that inhibition of miR-222 induced the expression of its direct targets ARID1A and phosphatase and tensin homolog deleted on chromosome 10 (PTEN), and activated apoptosis of As-T cells in part through ARID1A downregulation. These results indicate that miR-222 plays an important role in arsenic-induced tumor growth.

  2. Role and mechanism of miR-222 in arsenic-transformed cells for inducing tumor growth

    PubMed Central

    Wang, Min; Li, Dongmei; Liu, Xue; Wang, Lin; Jiang, Chengfei; Shi, Zhumei; Qin, Lianju; Liu, Jiayin; Yang, Hushan; Liu, Ling-Zhi; He, Jun; Zhen, Linlin; Jiang, Bing-Hua

    2016-01-01

    High levels of arsenic in drinking water, soil, and air are associated with the higher incidences of several kinds of cancers worldwide, but the mechanism is yet to be fully discovered. Recently, a number of evidences show that dysregulation of microRNAs (miRNAs) induces carcinogenesis. In this study, we found miR-222 was upregulated in arsenic-transformed human lung epithelial BEAS-2B cells (As-T cells). Anti-miR-222 inhibitor treatment decreased cell proliferation, migration, tube formation, and induced apoptosis. In addition, anti-miR-222 inhibitor expression decreased tumor growth in vivo. We also found that inhibition of miR-222 induced the expression of its direct targets ARID1A and phosphatase and tensin homolog deleted on chromosome 10 (PTEN), and activated apoptosis of As-T cells in part through ARID1A downregulation. These results indicate that miR-222 plays an important role in arsenic-induced tumor growth. PMID:26909602

  3. Transforming growth factor-β1 up-regulates connexin43 expression in human granulosa cells

    PubMed Central

    Chen, Yu-Ching; Chang, Hsun-Ming; Cheng, Jung-Chien; Tsai, Horng-Der; Wu, Cheng-Hsuan; Leung, Peter C.K.

    2015-01-01

    STUDY QUESTION Does transforming growth factor-β1 (TGF-β1) up-regulate connexin43 (Cx43) to promote cell–cell communication in human granulosa cells? SUMMARY ANSWER TGF-β1 up-regulates Cx43 and increases gap junction intercellular communication activities (GJIC) in human granulosa cells, and this effect occurs via the activin receptor-like kinase (ALK)5-mediated Sma- and Mad-related protein (SMAD)2/3-SMAD4-dependent pathway. WHAT IS KNOWN ALREADY TGF-β1 and its receptors are expressed in human granulosa cells, and follicular fluid contains TGF-β1 protein. In human granulosa cells, Cx43 gap junctions play an important role in the development of follicles and oocytes. STUDY DESIGN, SIZE, DURATION This is an experimental study which was performed over a 1-year period. PARTICIPANTS/MATERIALS, SETTING, METHODS Immortalized human granulosa cells (SVOG cells) and primary human granulosa-lutein cells obtained from women undergoing IVF in an academic research center were used as the study models. Cx43 mRNA and protein expression levels were examined after exposure of SVOG cells to recombinant human TGF-β1. An activin/TGF-β type I receptor inhibitor, SB431542, and small interfering RNAs targeting ALK4, ALK5, SMAD2, SMAD3 and SMAD4 were used to verify the specificity of the effects and to investigate the molecular mechanisms. Real-time-quantitative PCR and western blot analysis were used to detect the specific mRNA and protein levels, respectively. GJIC between SVOG cells were evaluated using a scrape loading and dye transfer assay. Results were analyzed by one-way analysis of variance. MAIN RESULTS AND THE ROLE OF CHANCE TGF-β1 treatment increased phosphorylation of SMAD2/3 (P < 0.0001) and up-regulated Cx43 mRNA and protein levels (P < 0.001) in SVOG cells and these stimulatory effects were abolished by the TGF-β type I receptor inhibitor SB431542. In addition, the up-regulatory effect of TGF-β1 on Cx43 expression (mRNA and protein) was confirmed in primary

  4. Neurons promote macrophage proliferation by producing transforming growth factor-beta2.

    PubMed

    Dobbertin, A; Schmid, P; Gelman, M; Glowinski, J; Mallat, M

    1997-07-15

    The infiltration of bone marrow-derived macrophages into the CNS contributes to growth and reactions of microglia during development or after brain injury. The proliferation of microglial cells is stimulated by colony-stimulating factor 1 (CSF-1), an astrocyte-produced growth factor that acts on mononuclear phagocytes. In the present study, we have shown, using an in vitro model system, that rodent neurons obtained from the developing cerebral cortex produce a soluble factor that strongly enhances the proliferation of macrophages cultured in the presence of CSF-1. Both macrophages isolated from the developing brain and those from the adult bone marrow were stimulated. Kinetic analyses of [3H]thymidine incorporation into macrophages indicated that their response to the neuron-derived factor involved a shortening of the cycle of proliferating cells. The effect of neurons on macrophages was blocked in the presence of antibodies neutralizing transforming growth factor-beta2 (TGF-beta2), whereas recombinant TGF-beta2 stimulated macrophage proliferation in the presence of CSF-1. Neuronal secretion of TGF-beta2 was confirmed by reverse transcription-PCR detection of TGF-beta2 transcripts and immunodetection of the protein within neurons and in their culture medium. In situ hybridization and immunohistochemical experiments showed neuronal expression of TGF-beta2 in sections of cerebral cortex obtained from 6-d-old rats, an age at which extensive developmental recruitment of macrophages occurs in this cerebral region. Altogether, our results provide direct evidence that neurons have the capacity to promote brain macrophage proliferation and demonstrate the role of TGF-beta2 in this neuronal function.

  5. Effect of transforming growth factor beta on synthesis of glycosaminoglycans by human lung fibroblasts

    SciTech Connect

    Dubaybo, B.A.; Thet, L.A. )

    1990-09-01

    The processes of lung growth, injury, and repair are characterized by alterations in fibroblast synthesis and interstitial distribution of extracellular matrix components. Transforming growth factor beta (TGF-beta), which is postulated to play a role in modulating lung repair, alters the distribution of several matrix components such as collagen and fibronectin. We studied the effect of TGF-beta on the synthesis and distribution of the various glycosaminoglycans (GAGs) and whether these effects may explain its role in lung repair. Human diploid lung fibroblasts (IMR-90) were exposed to various concentrations of TGF-beta (0-5 nM) for variable periods of time (0-18 h). Newly synthesized GAGs were labeled with either (3H)glucosamine or (35S)sulfate. Individual GAGs were separated by size exclusion chromatography after serial enzymatic and chemical digestions and quantitated using scintillation counting. There was a dose-dependent increase in total GAG synthesis with maximal levels detected after 6 h of exposure. This increase was noted in all individual GAG types measured and was observed in both the cell associated GAGs (cell-matrix fraction) as well as the GAGs released into the medium (medium fraction). In the cell-matrix fraction, TGF-beta increased the proportion of heparan sulfate that was membrane bound as well as the proportion of dermatan sulfate in the intracellular compartment. In the medium fraction, TGF-beta increased the proportion of hyaluronic acid, chondroitin sulfate and dermatan sulfate released. We conclude that the role of TGF-beta in lung growth and repair may be related to increased synthesis of GAGs by human lung fibroblasts as well as alterations in the distribution of individual GAGs.

  6. Transforming growth factor-beta: its role in ovarian follicle development.

    PubMed

    Rosairo, Davina; Kuyznierewicz, Ileana; Findlay, Jock; Drummond, Ann

    2008-12-01

    Ovarian follicular growth and differentiation in response to transforming growth factor-beta (TGFB) was investigated using postnatal and immature ovarian models. TGFB ligand and receptor mRNAs were present in the rat ovary 4-12 days after birth and at day 25. In order to assess the impact of TGFB1 on follicle growth and transition from the primordial through to the primary and preantral stages of development, we established organ cultures with 4-day-old rat ovaries. After 10 days in culture with FSH, TGFB1, or a combination of the two, ovarian follicle numbers were counted and an assessment of atresia was undertaken using TUNEL. Preantral follicle numbers declined significantly when treated with the combination of FSH and TGFB1, consistent with our morphological appraisal suggesting an increase in atretic primary and preantral follicles. To investigate the mechanisms behind the actions of TGFB1, we isolated granulosa cells and treated them with FSH and TGFB1. Markers of proliferative, steroidogenic, and apoptotic capacity were measured by real-time PCR. Cyclin D2 mRNA expression by granulosa cells was significantly increased in response to the combination of FSH and TGFB. The expression of forkhead homolog in rhabdomyosarcoma (Foxo1) mRNA by granulosa cells was significantly reduced in the presence of both FSH and TGFB1, individually and in combination regimes. By contrast, the expression of steroidogenic enzymes/proteins was largely unaffected by TGFB1. These data suggest an inhibitory role for TGFB1 (in the presence of FSH) in follicle development and progression.

  7. Extracellular matrix proteoglycan decorin-mediated myogenic satellite cell responsiveness to transforming growth factor-beta1 during cell proliferation and differentiation Decorin and transforming growth factor-beta1 in satellite cells.

    PubMed

    Li, Xuehui; McFarland, Douglas C; Velleman, Sandra G

    2008-10-01

    Transforming growth factor-beta1 (TGF-beta1) is a potent inhibitor of muscle cell proliferation and differentiation. Decorin, a small proteoglycan in the extracellular matrix, binds to TGF-beta1 and modulates the activity of TGF-beta1 during muscle cell growth and development. However, its interaction with TGF-beta1 and involvement in myogenesis is not well characterized. In the present study, chicken myogenic satellite cells, myogenic precursors for muscle growth and repair, were isolated from the pectoralis major muscle and used to investigate the biological function of TGF-beta1 and decorin during myogenesis. The over-expression of decorin in satellite cells significantly increased cell proliferation, compared to the control cells. Consistent with this result, reducing decorin expression decreased cell proliferation, which suggests a decorin-mediated mechanism is involved in the regulation of myogenic satellite cell proliferation. Satellite cells over-expressing decorin were less sensitive to TGF-beta1 during proliferation, which indicates that decorin may sequester TGF-beta1 leading to increased proliferation. During satellite cell differentiation, the over-expression of decorin induced differentiation by increasing the muscle specific creatine kinase concentration. However, the addition of TGF-beta1 diminished decorin-mediated cell responsiveness to TGF-beta1 during differentiation. Taken together, these results suggest that decorin induces myogenic satellite cell proliferation and differentiation by regulating cellular responsiveness to TGF-beta1. An alternative TGF-beta1-independent pathway may be involved in the regulation of satellite cells by decorin.

  8. Preparation and identification of anti-transforming growth factor β1 U1 small nuclear RNA chimeric ribozyme in vitro

    PubMed Central

    Lin, Ju-Sheng; Song, Yu-Hu; Kong, Xin-Juan; Li, Bin; Liu, Nan-Zhi; Wu, Xiao-Li; Jin, You-Xin

    2003-01-01

    AIM: To study the preparation and cleavage activity of anti-transforming growth factor (TGF)β1 U1 small nuclear (sn) RNA chimeric hammerhead ribozymes in vitro. METHODS: TGFβ1 partial gene fragment was cloned into T-vector at the downstream of T7 promoter. 32p-labeled TGFβ1 partial transcripts as target RNA were transcribed in vitro and purified by denaturing polyacrylamide gel electrophoresis (PAGE). Anti-TGFβ1 ribozymes were designed by computer, then synthetic ribozyme fragments were cloned into the U1 ribozyme vector pZeoU1EcoSpe containing U1 snRNA promoter/enhancer and terminator. 32p-labeled U1 snRNA chimeric ribozyme transcripts were gel-purified, incubated with target-RNAs at different conditions and autoradiographed after running denaturing PAGE. RESULTS: Active U1snRNA chimeric ribozyme (U1Rz803) had the best cleavage activity at 50 °C; at 37 °C, it was active, Km = 34.48 nmol/L, Kcat = 0.14 min-1; while the point mutant ribozyme U1Rz803m had no cleavage activity, so these indicated the design of U1Rz803 was correct. CONCLUSION: U1Rz803 prepared in this study possessed the perfect specific catalytic cleavage activity. These results indicate U1 snRNA chimeric ribozyme U1Rz803 may suppress the expression of TGFβ1 in vivo, therefore it may provide a new avenue for the treatment of liver fibrosis in the future. PMID:12632521

  9. Cyclic stretching force selectively up-regulates transforming growth factor-beta isoforms in cultured rat mesangial cells.

    PubMed Central

    Riser, B. L.; Cortes, P.; Heilig, C.; Grondin, J.; Ladson-Wofford, S.; Patterson, D.; Narins, R. G.

    1996-01-01

    Glomerular distention from increased intraglomerular pressure stretches mesangial cells (MCs). Stretching MCs in culture stimulates extracellular matrix accumulation, suggesting that this may be a mechanism for glomerular hypertension-associated glomerulosclerosis. We examined whether mechanical stretching serves as a stimulus for the synthesis and activation of the prosclerotic molecule transforming growth factor (TGF)-beta, thus providing a potential system for auto-induction of extracellular matrix. Rat MCs cultured on flexible-bottom plates were subjected to cyclic stretching for up to 3 days and then assayed for TGF-beta mRNA, secretion of TGF-beta, and localization of active TGF-beta by immunostaining. MCs contained mRNA for all three mammalian isoforms of TGF-beta. Cyclic stretching for 36 hours increased TGF-beta1 and TGF-beta3 mRNA levels approximately twofold, without altering the levels of TGF-beta2 mRNA. This was followed at 48 to 72 hours by the increased secretion of both latent and active TGF-beta1. Latent, but not active, TGF-beta3 secretion also increased whereas the levels of TGF-beta2 were unaffected by mechanical force. The stretching force in this system is unequally distributed over the culture membrane. Localization of active TGF-beta by immunostaining demonstrated that the quantity of cell-associated cytokine across the culture was directly proportional to the zonal amplitude of the stretching force. These results demonstrate that stretching force stimulates MCs to selectively release and activate TGF-beta1. This mechanical induction of TGF-beta1 may help explain the increased extracellular matrix associated with intraglomerular hypertension. Images Figure 1 Figure 3 PMID:8669477

  10. Functional mapping of quantitative trait loci underlying growth trajectories using a transform-both-sides logistic model.

    PubMed

    Wu, Rongling; Ma, Chang-Xing; Lin, Min; Wang, Zuoheng; Casella, George

    2004-09-01

    The incorporation of developmental control mechanisms of growth has proven to be a powerful tool in mapping quantitative trait loci (QTL) underlying growth trajectories. A theoretical framework for implementing a QTL mapping strategy with growth laws has been established. This framework can be generalized to an arbitrary number of time points, where growth is measured, and becomes computationally more tractable, when the assumption of variance stationarity is made. In practice, however, this assumption is likely to be violated for age-specific growth traits due to a scale effect. In this article, we present a new statistical model for mapping growth QTL, which also addresses the problem of variance stationarity, by using a transform-both-sides (TBS) model advocated by Carroll and Ruppert (1984, Journal of the American Statistical Association 79, 321-328). The TBS-based model for mapping growth QTL cannot only maintain the original biological properties of a growth model, but also can increase the accuracy and precision of parameter estimation and the power to detect a QTL responsible for growth differentiation. Using the TBS-based model, we successfully map a QTL governing growth trajectories to a linkage group in an example of forest trees. The statistical and biological properties of the estimates of this growth QTL position and effect are investigated using Monte Carlo simulation studies. The implications of our model for understanding the genetic architecture of growth are discussed.

  11. Morphological Transformation and Force Generation of Active Cytoskeletal Networks

    PubMed Central

    Maruri, Daniel; Kamm, Roger D.

    2017-01-01

    Cells assemble numerous types of actomyosin bundles that generate contractile forces for biological processes, such as cytokinesis and cell migration. One example of contractile bundles is a transverse arc that forms via actomyosin-driven condensation of actin filaments in the lamellipodia of migrating cells and exerts significant forces on the surrounding environments. Structural reorganization of a network into a bundle facilitated by actomyosin contractility is a physiologically relevant and biophysically interesting process. Nevertheless, it remains elusive how actin filaments are reoriented, buckled, and bundled as well as undergo tension buildup during the structural reorganization. In this study, using an agent-based computational model, we demonstrated how the interplay between the density of myosin motors and cross-linking proteins and the rigidity, initial orientation, and turnover of actin filaments regulates the morphological transformation of a cross-linked actomyosin network into a bundle and the buildup of tension occurring during the transformation. PMID:28114384

  12. Improvement of activated sludge bacteria growth by low intensity ultrasound

    NASA Astrophysics Data System (ADS)

    Yan, Y. X.; Ding, J. Y.; Gao, J. L.

    2016-08-01

    Influence of low intensity ultrasound (US) on growth rate of bacteria separated from aerobic activated sludge was studied. In order to reveal the optimal ultrasonic conditions,specific oxygen uptake rate (SOUR) of activated sludge was first detected and results showed that the maximum SOUR was obtained (increased by 40%) at US intensity of 3 Wcm-2 and irradiation time of 10min. Under the optimal conditions, 2 species of bacteria isolated from activated sludge were sonicated and then cultivated for 36h, and increment of 6% and 10% of growth rate were detected for the 2 species of bacteria, respectively, indicating US irradiation of suitable parameters effectively improved activated sludge bacteria growth.

  13. Some New Observations on Activation Energy of Crystal Growth for Thermally Activated Crystallization.

    PubMed

    Mehta, N; Kumar, A

    2016-02-18

    Calorimetric study of glass/crystal phase transformation in disordered semiconductors is a significant tool for understanding their crystallization kinetics. Such studies provide the basis for practical application of glasses. Differential scanning calorimetry (DSC) is one of the advanced techniques for the analysis of thermally induced crystallization in glassy or amorphous systems. We are reporting the nonisothermal DSC measurements on four amorphous systems of Se70Te30 alloy with Ag, Cd, Sb, and Zn as chemical modifiers. In general, the rate constant (K) shows Arrhenian dependence on temperature (T), i.e., K = K0 exp (-Eg/RT) where Eg is the activation energy of crystal growth and K0 is called the pre-exponential factor of rate constant. In the present work, an experiment is designed to see the effect of composition on the activation energy of crystal growth. We have found Meyer-Neldel relation (MNR) between Eg and K0 for present systems. Another interesting feature of present work is the observation of further relation between Meyer-Neldel prefactor and Meyer-Neldel energy.

  14. Studies on Saccharomyces cerevisiae under carbon-limiting growth transformed with plasmid pCYG4 that carries the gene for NADP-GDH.

    PubMed

    Lima Filho, J L; Ledingham, W M

    1990-02-01

    The gene (GDH1) coding for the NADP-linked glutamate dehydrogenase system (NADP-GDH) has been cloned from Saccharomyces cerevisiae strain. Cells being transformed by the NADP-GDH gene on a 2 micron bared vector (pCYG4) plasmid confering 11-fold higher level on expressed GDH activity over the wild-type cells. The behavior of these cells was investigated under chemostatic growth with a carbon rate-limiting nutrient. Specific growth rates of cells carrying plasmid pCYG4 were found to be slightly slower than wild type cells. Furthermore, the NADP-GDH activity increases proportionally with the dilution rate. In addition, oscillations in the NADP-GDH activity, especially at a dilution rate up to 0.15/h, are probably consequential on the appearance of a changing mixed population (cells with and without plasmids).

  15. Increased susceptibility to atrial fibrillation secondary to atrial fibrosis in transgenic goats expressing transforming growth factor - B1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in people with significant morbidity and mortality. There is a strong association between atrial fibrosis and AF. Transforming growth factor B1 (TGF-B1) is an essential mediator of atrial fibrosis in animal models and human pat...

  16. Vertebral Artery Aneurysm Mimicking as Left Subclavian Artery Aneurysm in a Patient with Transforming Growth Factor Beta Receptor II Mutation.

    PubMed

    Afifi, Rana O; Dhillon, Baltej Singh; Sandhu, Harleen K; Charlton-Ouw, Kristofer M; Estrera, Anthony L; Azizzadeh, Ali

    2015-10-01

    We report successful endovascular repair of a left vertebral artery aneurysm in a patient with transforming growth factor beta receptor II mutation. The patient was initially diagnosed with a left subclavian artery aneurysm on computed tomography angiography. The patient consented to publication of this report.

  17. Hepatocyte growth factor counteracts transforming growth factor-beta1, through attenuation of connective tissue growth factor induction, and prevents renal fibrogenesis in 5/6 nephrectomized mice.

    PubMed

    Inoue, Tsutomu; Okada, Hirokazu; Kobayashi, Tatsuya; Watanabe, Yusuke; Kanno, Yoshihiko; Kopp, Jeffrey B; Nishida, Takashi; Takigawa, Masaharu; Ueno, Munehisa; Nakamura, Toshikazu; Suzuki, Hiromichi

    2003-02-01

    We investigated the mechanism of the anti-fibrotic effects of hepatocyte growth factor (HGF) in the kidney, with respect to its effect on connective tissue growth factor (CTGF), a down-stream, profibrotic mediator of transforming growth factor-beta1 (TGF-beta1). In wild-type (WT) mice with 5/6 nephrectomy (Nx), HGF and TGF-beta1 mRNAs increased transiently in the remnant kidney by week 1 after the Nx, returned to baseline levels, and increased again at weeks 4 to 12. In contrast, CTGF and alpha1(I) procollagen (COLI) mRNAs increased in parallel with HGF and TGF-beta1 during the early stage, but did not re-increase during the late stage. In the case of TGF-beta1 transgenic (TG) mice with 5/6 Nx, excess TGF-beta1 derived from the transgene enhanced CTGF expression significantly in the remnant kidney, accordingly accelerating renal fibrogenesis. Administration of dHGF (5.0 mg/kg/day) to TG mice with 5/6 Nx for 4 weeks from weeks 2 to 6 suppressed CTGF expression in the remnant kidney, attenuating renal fibrosis and improving the survival rate. In an experiment in vitro, renal tubulointerstitial fibroblasts (TFB) were co-cultured with proximal tubular epithelial cells (PTEC). Pretreatment with HGF reduced significantly CTGF induction in PTEC by TGF-beta1, consequently suppressing COLI synthesis in TFB. In conclusion, HGF can block, at least partially, renal fibrogenesis promoted by TGF-beta1 in the remnant kidney, via attenuation of CTGF induction.

  18. Radiation-Induced Liver Fibrosis Is Mitigated by Gene Therapy Inhibiting Transforming Growth Factor-{beta} Signaling in the Rat

    SciTech Connect

    Du Shisuo; Qiang Ming; Zeng Zhaochong; Zhou Jian; Tan Yunshan; Zhang Zhengyu; Zeng Haiying; Liu Zhongshan

    2010-12-01

    Purpose: We determined whether anti-transforming growth factor-{beta} (TGF-{beta}) intervention could halt the progression of established radiation-induced liver fibrosis (RILF). Methods and Materials: A replication-defective adenoviral vector expressing the extracellular portion of human T{beta}RII and the Fc portion of immunoglobulin G fusion protein (AdT{beta}RIIFc) was produced. The entire rat liver was exposed to 30 Gy irradiation to generate a RILF model (RILFM). Then, RILFM animals were treated with AdT{beta}RIIFc (1 x 10{sup 11} plaque-forming units [PFU] of T{beta}RII), control virus (1 x 10{sup 11} PFU of AdGFP), or saline. Delayed radiation liver injury was assessed by histology and immunohistochemistry. Chronic oxidative stress damage, hepatic stellate cell activation, and hepatocyte regeneration were also analyzed. Results: In rats infected with AdT{beta}RIIFc, fibrosis was significantly improved compared with rats treated with AdGFP or saline, as assessed by histology, hydroxyproline content, and serum level of hyaluronic acid. Compared with AdGFP rats, AdT{beta}RIIFc-treated rats exhibited decreased oxidative stress damage and hepatic stellate cell activation and preserved liver function. Conclusions: Our results demonstrate that TGF-{beta} plays a critical role in the progression of liver fibrosis and suggest that anti-TGF-{beta} intervention is feasible and ameliorates established liver fibrosis. In addition, chronic oxidative stress may be involved in the progression of RILF.

  19. Identification of a mutation in the human raloxifene response element of the transforming growth factor-beta 3 gene.

    PubMed Central

    Han, K. O.; Kang, Y. S.; Hwang, C. S.; Moon, I. G.; Yim, C. H.; Chung, H. Y.; Jang, H. C.; Yoon, H. K.; Han, I. K.; Choi, Y. K.

    2001-01-01

    The human transforming growth factor-beta 3 (TGF-beta 3) is an important cytokine to maintain bone mass by inhibiting osteoclast differentiation. Recently raloxifene response element (RRE), a new enhancer with a polypurine sequence for estrogen receptor (ER)-mediated gene activation, was identified on the TGF-beta 3 gene. Functional analysis of the RRE-mediated pathway has shown that this would be an important pathway for bone preserving effect. We found a novel mutation in the RRE sequence by single-strand conformational polymorphism analysis in one of 200 Korean women. Cloning and sequencing revealed a heterozygote in which one allele had an insertion of 20 nucleotides (AGAGAGGGAGAGGGAGA GGG) between nucleotide +71 and +72 and a point mutation at nucleotide +75 (G-A transition), and the other allele had normal sequence. The insertion was a nearly perfect tandem duplication of the wild type DNA sequence. The bone mineral density of the affected woman was not much lower than that of age-matched controls. Transient transfection of the mutant allele showed no significantly different activity compared with that of the wild type allele. These observations suggest that the heterozygote variation of the RRE sequence seems not to be operative in determination of bone mass. PMID:11641521

  20. B cell-derived transforming growth factor-β1 expression limits the induction phase of autoimmune neuroinflammation

    PubMed Central

    Bjarnadóttir, Kristbjörg; Benkhoucha, Mahdia; Merkler, Doron; Weber, Martin S.; Payne, Natalie L.; Bernard, Claude C. A.; Molnarfi, Nicolas; Lalive, Patrice H.

    2016-01-01

    Studies in experimental autoimmune encephalomyelitis (EAE), a murine model of multiple sclerosis (MS), have shown that regulatory B cells modulate the course of the disease via the production of suppressive cytokines. While data indicate a role for transforming growth factor (TGF)-β1 expression in regulatory B cell functions, this mechanism has not yet been tested in autoimmune neuroinflammation. Transgenic mice deficient for TGF-β1 expression in B cells (B–TGF-β1−/−) were tested in EAE induced by recombinant mouse myelin oligodendrocyte glycoprotein (rmMOG). In this model, B–TGF-β1−/− mice showed an earlier onset of neurologic impairment compared to their littermate controls. Exacerbated EAE susceptibility in B–TGF-β1−/− mice was associated with augmented CNS T helper (Th)1/17 responses. Moreover, selective B cell TGF-β1–deficiency increased the frequencies and activation of myeloid dendritic cells, potent professional antigen-presenting cells (APCs), suggesting that B cell-derived TGF-β1 can constrain Th1/17 responses through inhibition of APC activity. Collectively our data suggest that B cells can down-regulate the function of APCs, and in turn encephalitogenic Th1/17 responses, via TGF-β1, findings that may be relevant to B cell-targeted therapies. PMID:27708418

  1. Mutation of the endogenous p53 gene in cells transformed by HPV-16 E7 and EJ c-ras confers a growth advantage involving an autocrine mechanism.

    PubMed Central

    Peacock, J W; Benchimol, S

    1994-01-01

    Rat embryo fibroblasts transformed with the HPV-16 E7 gene and the activated c-H-ras gene fall into two distinct phenotypic classes. At high cell density, clones of one class form colonies in methylcellulose supplemented with low serum; at low cell density, these cells display responsiveness to mitogenic factors present in serum-free conditioned medium from rat embryo fibroblasts. In contrast, clones of the second class exhibit an absolute dependency on growth factors present in serum at all cell densities in the methylcellulose colony assay and fail to respond to conditioned medium. We find that the status of the endogenous p53 gene is tightly correlated with these two classes of clones. Clones of the first class contain missense mutations in the p53 gene and have lost the wild-type allele. Clones of the second class express wild-type p53 protein. The importance of mutant p53 expression in reducing the growth factor dependency of transformed clones was confirmed in a separate series of experiments in which rat embryo fibroblasts were transformed with three genes, E7 + ras + mutant p53. The growth behaviour of these triply transfected clones was similar to that of the E7 + ras clones expressing endogenous mutant p53. We demonstrate that the enhanced proliferation of E7 + ras clones expressing mutant p53 protein involves an autocrine mechanism. Images PMID:8131742

  2. Universal features in the growth dynamics of religious activities

    NASA Astrophysics Data System (ADS)

    Picoli, S., Jr.; Mendes, R. S.

    2008-03-01

    We quantify and analyze the growth dynamics of a religious group in 140 countries for a 47-year period (1959-2005). We find that (i) the distribution of annual logarithmic growth rates exhibits the same functional form for distinct size scales and (ii) the standard deviation of growth rates scales with size as a power law. Both findings hold for distinct measures of religious activity. These results are in surprising agreement with those found in the study of economic activities and scientific research, suggesting that religious activities are governed by universal growth mechanisms. We also compare the empirical findings on religious activities with the predictions of general models recently proposed in the context of complex organizations. Our findings should provide useful information for a better understanding of the mechanisms governing the growth of religion.

  3. Differential Regulation of Human Thymosin Beta 15 Isoforms by Transforming Growth Factor Beta 1

    PubMed Central

    Banyard, Jacqueline; Barrows, Courtney; Zetter, Bruce R.

    2009-01-01

    We recently identified an additional isoform of human thymosin beta 15 (also known as NB-thymosin beta, gene name TMSB15A) transcribed from an independent gene, and designated TMSB15B. The purpose of this study was to investigate whether these isoforms were differentially expressed and functional. Our data show that the TMSB15A and TMSB15B isoforms have distinct expression patterns in different tumor cell lines and tissues. TMSB15A was expressed at higher levels in HCT116, DU145, LNCaP and LNCaP-LN3 cancer cells. In MCF-7, SKOV-3, HT1080 and PC-3MLN4 cells, TMSB15A and TMSB15B showed approximately equivalent levels of expression, while TMSB15B was the predominant isoform expressed in PC-3, MDA-MB-231, NCI-H322 and Caco-2 cancer cells. In normal human prostate and prostate cancer tissues, TMSB15A was the predominant isoform expressed. In contrast, normal colon and colon cancer tissue expressed predominantly TMSB15B. The two gene isoforms are also subject to different transcriptional regulation. Treatment of MCF-7 breast cancer cells with transforming growth factor beta 1 repressed TMSB15A expression but had no effect on TMSB15B. siRNA specific to the TMSB15B isoform suppressed cell migration of prostate cancer cells to epidermal growth factor, suggesting a functional role for this second isoform. In summary, our data reveal different expression patterns and regulation of a new thymosin beta 15 gene paralog. This may have important consequences in both tumor and neuronal cell motility. PMID:19296525

  4. Transforming growth factor beta abrogates the effects of hematopoietins on eosinophils and induces their apoptosis

    PubMed Central

    1994-01-01

    Hematopoietins, interleukin (IL)-3, IL-5, and granulocyte/macrophage colony-stimulating factor (GM-CSF) have previously been shown to prolong eosinophil survival and abrogate apoptosis. The objective of this study was to investigate the effect of transforming growth factor beta (TGF-beta) on eosinophil survival and apoptosis. Eosinophils from peripheral blood of mildly eosinophilic donors were isolated to > 97% purity using discontinuous Percoll density gradient. Eosinophils were cultured with hematopoietins with or without TGF-beta for 4 d and their viability was assessed. We confirmed previous observations that hematopoietins prolonged eosinophil survival and inhibited apoptosis. TGF-beta at concentrations > or = 10(-12) M abrogated the survival- prolonging effects of hematopoietins in a dose-dependent manner and induced apoptosis as determined by DNA fragmentation in agarose gels. The effect of TGF-beta was blocked by an anti-TGF-beta antibody. The anti-TGF-beta antibody also prolonged eosinophil survival on its own. The culture of eosinophils with IL-3 and GM-CSF stimulated the synthesis of GM-CSF and IL-5, respectively, suggesting an autocrine mechanism of growth factor production. TGF-beta inhibited the synthesis of GM-CSF and IL-5 by eosinophils. TGF-beta did not have any effect on the expression of GM-CSF receptors on eosinophils. We also studied the effect of TGF-beta on eosinophil function and found that TGF-beta inhibited the release of eosinophil peroxidase. Thus, TGF-beta seems to inhibit eosinophil survival and function. The inhibition of endogenous synthesis of hematopoietins may be one mechanism by which TGF-beta blocks eosinophil survival and induces apoptosis. PMID:8113672

  5. Using the Learning Activities Survey to Examine Transformative Learning Experiences in Two Graduate Teacher Preparation Courses

    ERIC Educational Resources Information Center

    Caruana, Vicki; Woodrow, Kelli; Pérez, Luis

    2015-01-01

    The Learning Activities Survey (LAS) detected whether, and to what extent, a perspective transformation occurred during two graduate courses in teacher preparation. The LAS examined the types of learning identified as contributing to their transformative experiences. This study examined pre-service teachers' critical reflection of the course…

  6. Transforming growth factor-β evokes Ca2+ waves and enhances gene expression in human pulmonary fibroblasts.

    PubMed

    Mukherjee, Subhendu; Kolb, Martin R J; Duan, Fuqin; Janssen, Luke J

    2012-06-01

    Fibroblasts maintain the structural framework of animal tissue by synthesizing extracellular matrix molecules. Chronic lung diseases are characterized in part by changes in fibroblast numbers, properties, and more. Fibroblasts respond to a variety of growth factors, cytokines, and proinflammatory mediators. However, the signaling mechanisms behind these responses have not been fully explored. We sought to determine the role of Ca(2+) waves in transforming growth factor-β (TGF-β)-mediated gene expression in human pulmonary fibroblasts. Primary human pulmonary fibroblasts were cultured and treated with TGF-β and different blockers under various conditions. Cells were then loaded with the Ca(2+) indicator dye Oregon green, and Ca(2+) waves were monitored by confocal [Ca(2+)](i) fluorimetry. Real-time PCR was used to probe gene expression. TGF-β (1 nM) evoked recurring Ca(2+) waves. A 30-minute pretreatment of SD 208, a TGF-β receptor-1 kinase inhibitor, prevented Ca(2+) waves from being evoked by TGF-β. The removal of external Ca(2+) completely occluded TGF-β-evoked Ca(2+) waves. Cyclopiazonic acid, an inhibitor of the internal Ca(2+) pump, evoked a relatively slowly developing rise in Ca(2+) waves compared with the rapid changes evoked by TGF-β, but the baseline fluorescence was increased. Ryanodine (10(-5) M) also blocked TGF-β-mediated Ca(2+) wave activity. Real-time PCR showed that TGF-β rapidly and dramatically increased the gene expression of collagen A1 and fibronectin. This increase was blocked by ryanodine treatment and cyclopiazonic acid. We conclude that, in human pulmonary fibroblasts, TGF-β acts on ryanodine-sensitive channels, leading to Ca(2+) wave activity, which in turn amplifies extracellular matrix gene expression.

  7. Transforming growth factor-α mediates estrogen-induced upregulation of glutamate transporter GLT-1 in rat primary astrocytes

    PubMed Central

    Lee, Eunsook; Sidoryk-Węgrzynowicz, Marta; Yin, Zhaobao; Webb, Anton; Son, Deok-Soo; Aschner, Michael

    2012-01-01

    Glutamate transporter-1 (GLT-1) plays a central role in preventing excitotoxicity by removing excess glutamate from the synaptic clefts. 17β-estradiol (E2) and tamoxifen (TX), a selective estrogen receptor modulator (SERM), afford neuroprotection in a range of experimental models. However, the mechanisms that mediate E2 and TX neuroprotection have yet to be elucidated. We tested the hypothesis that E2 and TX enhance GLT-1 function by increasing transforming growth factor (TGF)-α expression and thus, attenuate manganese (Mn)-induced impairment in astrocytic GLT-1 expression and glutamate uptake in rat neonatal primary astrocytes. The results showed that E2 (10 nM) and TX (1 μM) increased GLT-1 expression and reversed the Mn-induced reduction in GLT-1, both at the mRNA and protein levels. E2/TX also concomitantly reversed the Mn-induced inhibition of astrocytic glutamate uptake. E2/TX activated the GLT-1 promoter and attenuated the Mn-induced repression of the GLT-1 promoter in astrocytes. TGF-α knock-down (siRNA) abolished the E2/TX effect on GLT-1 expression, and inhibition of epidermal growth factor receptor (TGF-α receptor) suppressed the effect of E2/TX on GLT-1 expression and GLT-1 promoter activity. E2/TX also increased TGF-α mRNA and protein levels with a concomitant increase in astrocytic glutamate uptake. All estrogen receptors (ERs: ER-α ER-β and GPR30) were involved in mediating E2 effects on the regulation of TGF-α, GLT-1, and glutamate uptake. These results indicate that E2/TX increase GLT-1 expression in astrocytes via TGF-α signaling, thus offering an important putative target for the development of novel therapeutics for neurological disorders. PMID:22488924

  8. Transforming growth factor-α mediates estrogen-induced upregulation of glutamate transporter GLT-1 in rat primary astrocytes.

    PubMed

    Lee, Eunsook; Sidoryk-Wegrzynowicz, Marta; Yin, Zhaobao; Webb, Anton; Son, Deok-Soo; Aschner, Michael

    2012-07-01

    Glutamate transporter-1 (GLT-1) plays a central role in preventing excitotoxicity by removing excess glutamate from the synaptic clefts. 17β-Estradiol (E2) and tamoxifen (TX), a selective estrogen receptor (ER) modulator, afford neuroprotection in a range of experimental models. However, the mechanisms that mediate E2 and TX neuroprotection have yet to be elucidated. We tested the hypothesis that E2 and TX enhance GLT-1 function by increasing transforming growth factor (TGF)-α expression and, thus, attenuate manganese (Mn)-induced impairment in astrocytic GLT-1 expression and glutamate uptake in rat neonatal primary astrocytes. The results showed that E2 (10 nM) and TX (1 μM) increased GLT-1 expression and reversed the Mn-induced reduction in GLT-1, both at the mRNA and protein levels. E2/TX also concomitantly reversed the Mn-induced inhibition of astrocytic glutamate uptake. E2/TX activated the GLT-1 promoter and attenuated the Mn-induced repression of the GLT-1 promoter in astrocytes. TGF-α knockdown (siRNA) abolished the E2/TX effect on GLT-1 expression, and inhibition of epidermal growth factor receptor (TGF-α receptor) suppressed the effect of E2/TX on GLT-1 expression and GLT-1 promoter activity. E2/TX also increased TGF-α mRNA and protein levels with a concomitant increase in astrocytic glutamate uptake. All ERs (ER-α, ER-β, and G protein-coupled receptor 30) were involved in mediating E2 effects on the regulation of TGF-α, GLT-1, and glutamate uptake. These results indicate that E2/TX increases GLT-1 expression in astrocytes via TGF-α signaling, thus offering an important putative target for the development of novel therapeutics for neurological disorders.

  9. uPAR induces expression of transforming growth factor β and interleukin-4 in cancer cells to promote tumor-permissive conditioning of macrophages.

    PubMed

    Hu, Jingjing; Jo, Minji; Eastman, Boryana M; Gilder, Andrew S; Bui, Jack D; Gonias, Steven L

    2014-12-01

    Cancer cells condition macrophages and other inflammatory cells in the tumor microenvironment so that these cells are more permissive for cancer growth and metastasis. Conditioning of inflammatory cells reflects, at least in part, soluble mediators (such as transforming growth factor β and IL-4) that are released by cancer cells and alter the phenotype of cells of the innate immune system. Signaling pathways in cancer cells that potentiate this activity are incompletely understood. The urokinase receptor (uPAR) is a cell-signaling receptor known to promote cancer cell survival, proliferation, metastasis, and cancer stem cell-like properties. The present findings show that uPAR expression in diverse cancer cells, including breast cancer, pancreatic cancer, and glioblastoma cells, promotes the ability of these cells to condition co-cultured bone marrow-derived macrophages so that the macrophages express significantly increased levels of arginase 1, a biomarker of the alternatively activated M2 macrophage phenotype. Expression of transforming growth factor β was substantially increased in uPAR-expressing cancer cells via a mechanism that requires uPA-initiated cell signaling. uPAR also controlled expression of IL-4 in cancer cells via a mechanism that involves activation of ERK1/2. The ability of uPAR to induce expression of factors that condition macrophages in the tumor microenvironment may constitute an important mechanism by which uPAR promotes cancer progression.

  10. Hair Growth Promotion Activity and Its Mechanism of Polygonum multiflorum

    PubMed Central

    Li, Yunfei; Han, Mingnuan; Lin, Pei; He, Yanran; Yu, Jie; Zhao, Ronghua

    2015-01-01

    Polygonum multiflorum Radix (PMR) has long history in hair growth promotion and hair coloring in clinical applications. However, several crucial problems in its clinic usage and mechanisms are still unsolved or lack scientific evidences. In this research, C57BL/6J mice were used to investigate hair growth promotion activity and possible mechanism of PMR and Polygonum multiflorum Radix Preparata (PMRP). Hair growth promotion activities were investigated by hair length, hair covered skin ratio, the number of follicles, and hair color. Regulation effects of several cytokines involved in the hair growth procedure were tested, such as fibroblast growth factor (FGF-7), Sonic Hedgehog (SHH), β-catenin, insulin-like growth factor-1 (IGF-1), and hepatocyte growth factor (HGF). Oral PMR groups had higher hair covered skin ratio (100 ± 0.00%) than oral PMRP groups (48%~88%). However, topical usage of PMRP had about 90% hair covered skin ratio. Both oral administration of PMR and topically given PMRP showed hair growth promotion activities. PMR was considered to be more suitable for oral administration, while PMRP showed greater effects in external use. The hair growth promotion effect of oral PMR was most probably mediated by the expression of FGF-7, while topical PMRP promoted hair growth by the stimulation of SHH expression. PMID:26294926

  11. Identification of selected microorganisms from activated sludge capable of benzothiazole and benzotriazole transformation.

    PubMed

    Kowalska, Katarzyna; Felis, Ewa

    2015-01-01

    Benzothiazole (BT) and benzotriazole (BTA) are present in the environment - especially in urban and industrial areas, usually as anthropogenic micropollutants. BT and BTA have been found in the municipal and industrial wastewater, rivers, soil, groundwater, sediments and sludge. The origins of those substances' presence in the environment are various industry branches (food, chemical, metallurgical, electrical), households and surface runoff from industrial areas. Increasingly strict regulations on water quality and the fact that the discussed compounds are poorly biodegradable, make them a serious problem in the environment. Considering this, it is important to look for environmentally friendly and socially acceptable ways to remove BT and BTA. The aim of this study was to identify microorganisms capable of BT and BTA transformation or/and degradation in aquatic environment. Selected microorganisms were isolated from activated sludge. The identification of microorganisms capable of BT and BTA removal was possible using molecular biology techniques (PCR, DNA sequencing). Among isolated microorganisms of activated sludge are bacteria potentially capable of BT and BTA biotransformation and/or removal. The most common bacteria capable of BT and BTA transformation were Rhodococcus sp., Enterobacter sp., Arthrobacter sp. They can grow in a medium with BT and BTA as the only carbon source. Microorganisms previously adapted to the presence of the studied substances at a concentration of 10 mg/l, showed a greater rate of growth of colonies on media than microorganisms unconditioned to the presence of such compounds. Results of the biodegradation test suggest that BT was degraded to a greater extent than BTA, 98-100% and 11-19%, respectively.

  12. Spatial signalling mediated by the transforming growth factor-β signalling pathway during tooth formation

    PubMed Central

    He, Xin-Yu; Sun, Ke; Xu, Ruo-Shi; Tan, Jia-Li; Pi, Cai-Xia; Wan, Mian; Peng, Yi-Ran; Ye, Ling; Zheng, Li-Wei; Zhou, Xue-Dong

    2016-01-01

    Tooth development relies on sequential and reciprocal interactions between the epithelial and mesenchymal tissues, and it is continuously regulated by a variety of conserved and specific temporal-spatial signalling pathways. It is well known that suspensions of tooth germ cells can form tooth-like structures after losing the positional information provided by the epithelial and mesenchymal tissues. However, the particular stage in which the tooth germ cells start to form tooth-like structures after losing their positional information remains unclear. In this study, we investigated the reassociation of tooth germ cells suspension from different morphological stages during tooth development and the phosphorylation of Smad2/3 in this process. Four tooth morphological stages were designed in this study. The results showed that tooth germ cells formed odontogenic tissue at embryonic day (E) 14.5, which is referred to as the cap stage, and they formed tooth-like structures at E16.5, which is referred to as the early bell stage, and E18.5, which is referred to as the late bell stage. Moreover, the transforming growth factor-β signalling pathway might play a role in this process. PMID:27982023

  13. Integration of sexual trauma in a religious narrative: Transformation, resolution and growth among contemplative nuns

    PubMed Central

    Littlewood, Roland; Leavey, Gerard

    2013-01-01

    The psychological consequences of sexual abuse are generally serious and enduring, particularly when the perpetrator is known and trusted by the survivor. This paper explores the experiences of five contemplative nuns who were sexually abused by priests and the spiritual journeys that followed. In the context of an ethnographic study of contemplative practice, participant observation and in-depth interviews were used to examine the ways that the nuns sought to make sense of their experiences through a long process of solitary introspection. The pursuit of meaning was shaped by religious beliefs relating to forgiveness, sacrifice, and salvation. Thus, trauma was transformed into a symbolic religious narrative that shaped their sense of identity. They were able to restructure core beliefs and to manage their current relationships with priests more securely. They described regaining their spiritual well-being in ways that suggest a form of posttraumatic spiritual growth. We conclude by discussing the findings in the light of the existing literature on the interaction of trauma and spirituality. PMID:23296289

  14. Ion beam-induced amorphous-to-tetragonal phase transformation and grain growth of nanocrystalline zirconia.

    PubMed

    Lian, Jie; Zhang, Jiaming; Namavar, Fereydoon; Zhang, Yanwen; Lu, Fengyuan; Haider, Hani; Garvin, Kevin; Weber, W J; Ewing, Rodney C

    2009-06-17

    Nanocrystalline zirconia has recently attracted extensive research interest due to its unique mechanical, thermal and electrical properties as compared with bulk zirconia counterparts, and it is of particular importance for controlling the phase stability of different polymorphs (amorphous, cubic, tetragonal and monoclinic phases) in different size regimes. In this work, we performed ion beam bombardments on bilayers (amorphous and cubic) of nano-zirconia using 1 MeV Kr2+ irradiation. Transmission electron microscopy (TEM) analysis reveals that amorphous zirconia transforms to a tetragonal structure under irradiation at room temperature, suggesting that the tetragonal phase is more energetically favorable under these conditions. The final grain size of the tetragonal zirconia can be controlled by irradiation conditions. A slower kinetics in the grain growth from cubic nanocrystalline zirconia was found as compared with that for the tetragonal grains recrystallized from the amorphous layer. The radiation-induced nanograins of tetragonal ZrO2 are stable at ambient conditions and maintain their physical integrity over a long period of time after irradiation. These results demonstrated that ion beam methods provide the means to control the phase stability and structure of zirconia polymorphs.

  15. Seeded growth of metal-doped plasmonic oxide heterodimer nanocrystals and their chemical transformation.

    PubMed

    Ye, Xingchen; Reifsnyder Hickey, Danielle; Fei, Jiayang; Diroll, Benjamin T; Paik, Taejong; Chen, Jun; Murray, Christopher B

    2014-04-02

    We have developed a generalized seeded-growth methodology for the synthesis of monodisperse metal-doped plasmonic oxide heterodimer nanocrystals (NCs) with a near-unity morphological yield. Using indium-doped cadmium oxide (ICO) as an example, we show that a wide variety of preformed metal NCs (Au, Pt, Pd, FePt, etc.) can serve as the seeds for the tailored synthesis of metal-ICO heterodimers with exquisite size, shape, and composition control, facilitated by the delayed nucleation mechanism of the CdO phase. The metal-ICO heterodimers exhibit broadly tunable near-infrared localized surface plasmon resonances, and dual plasmonic bands are observed for Au-ICO heterodimers. We further demonstrate that the oxide domain of the Au-ICO heterodimers can be selectively and controllably transformed into a series of partially and completely hollow cadmium chalcogenide nanoarchitectures with unprecedented structural complexity, leaving the metal domain intact. Our work not only represents an exciting addition to the rapidly expanding library of chemical reactions that produce colloidal hybrid NCs, but it also provides a general route for the bottom-up chemical design of multicomponent metal-oxide-semiconductor NCs in a rational and sequential manner.

  16. Transforming growth factor β1 inhibition protects from noise-induced hearing loss

    PubMed Central

    Murillo-Cuesta, Silvia; Rodríguez-de la Rosa, Lourdes; Contreras, Julio; Celaya, Adelaida M.; Camarero, Guadalupe; Rivera, Teresa; Varela-Nieto, Isabel

    2015-01-01

    Excessive exposure to noise damages the principal cochlear structures leading to hearing impairment. Inflammatory and immune responses are central mechanisms in cochlear defensive response to noise but, if unregulated, they contribute to inner ear damage and hearing loss. Transforming growth factor β (TGF-β) is a key regulator of both responses and high levels of this factor have been associated with cochlear injury in hearing loss animal models. To evaluate the potential of targeting TGF-β as a therapeutic strategy for preventing or ameliorating noise-induced hearing loss (NIHL), we studied the auditory function, cochlear morphology, gene expression and oxidative stress markers in mice exposed to noise and treated with TGF-β1 peptidic inhibitors P17 and P144, just before or immediately after noise insult. Our results indicate that systemic administration of both peptides significantly improved both the evolution of hearing thresholds and the degenerative changes induced by noise-exposure in lateral wall structures. Moreover, treatments ameliorated the inflammatory state and redox balance. These therapeutic effects were dose-dependent and more effective if the TGF-β1 inhibitors were administered prior to inducing the injury. In conclusion, inhibition of TGF-β1 actions with antagonistic peptides represents a new, promising therapeutic strategy for the prevention and repair of noise-induced cochlear damage. PMID:25852546

  17. Adaptive and innate transforming growth factor beta signaling impact herpes simplex virus 1 latency and reactivation.

    PubMed

    Allen, Sariah J; Mott, Kevin R; Wechsler, Steven L; Flavell, Richard A; Town, Terrence; Ghiasi, Homayon

    2011-11-01

    Innate and adaptive immunity play important protective roles by combating herpes simplex virus 1 (HSV-1) infection. Transforming growth factor β (TGF-β) is a key negative cytokine regulator of both innate and adaptive immune responses. Yet, it is unknown whether TGF-β signaling in either immune compartment impacts HSV-1 replication and latency. We undertook genetic approaches to address these issues by infecting two different dominant negative TGF-β receptor type II transgenic mouse lines. These mice have specific TGF-β signaling blockades in either T cells or innate cells. Mice were ocularly infected with HSV-1 to evaluate the effects of restricted innate or adaptive TGF-β signaling during acute and latent infections. Limiting innate cell but not T cell TGF-β signaling reduced virus replication in the eyes of infected mice. On the other hand, blocking TGF-β signaling in either innate cells or T cells resulted in decreased latency in the trigeminal ganglia of infected mice. Furthermore, inhibiting TGF-β signaling in T cells reduced cell lysis and leukocyte infiltration in corneas and trigeminal ganglia during primary HSV-1 infection of mice. These findings strongly suggest that TGF-β signaling, which generally functions to dampen immune responses, results in increased HSV-1 latency.

  18. Transforming growth factor alpha induces collagen degradation and cell migration in differentiating human epidermal raft cultures.

    PubMed Central

    Turksen, K; Choi, Y; Fuchs, E

    1991-01-01

    When cultured on plastic and treated with transforming growth factor alpha (TGF alpha), human keratinocytes exhibit an increase in proliferation at the colony periphery, apparently as a consequence of enhanced cell migration (Barrandon and Green, 1987). To investigate the effects of TGF alpha on a differentiating stratified squamous epithelium and to begin to examine the molecular basis mediating this influence, we cultured human epidermal cells on a gelled lattice of collagen and fibroblasts, floating on the air-liquid interface. Under these conditions, raft cultures differentiate and exhibit morphological and biochemical features of human skin in vivo (Asselineau et al., 1986; Kopan et al., 1987). When 3-wk-old raft cultures were treated with TGF alpha, basal cells showed a marked increase in cell proliferation. At elevated concentrations of TGF alpha, the organization of cells within the artificial tissue changed and islands of basal cells entered the collagen matrix. Biochemical analysis of the response revealed that type I collagenase and gelatinase were induced by keratinocytes within 12 h after TGF alpha treatment. In contrast, invasion of basal cells into the collagen matrix was not significant until 48-72 h post-treatment, suggesting that collagenase and gelatinase production may be a prerequisite to this phenomenon. These results have important implications for the possible role of TGF alpha in squamous cell carcinoma and tumor invasion. Images PMID:1663788

  19. Metformin is a novel suppressor for transforming growth factor (TGF)-β1

    NASA Astrophysics Data System (ADS)

    Xiao, Han; Zhang, Jianshu; Xu, Zhonghe; Feng, Yenan; Zhang, Mingliang; Liu, Jianli; Chen, Ruifei; Shen, Jing; Wu, Jimin; Lu, Zhizhen; Fang, Xiaohong; Li, Jingyuan; Zhang, Youyi

    2016-06-01

    Metformin is a widely used first-line antidiabetic drug that has been shown to protect against a variety of specific diseases in addition to diabetes, including cardiovascular disorders, polycystic ovary syndrome, and cancer. However, the precise mechanisms underlying the diverse therapeutic effects of metformin remain elusive. Here, we report that transforming growth factor-β1 (TGF-β1), which is involved in the pathogenesis of numerous diseases, is a novel target of metformin. Using a surface plasmon resonance-based assay, we identified the direct binding of metformin to TGF-β1 and found that metformin inhibits [125I]-TGF-β1 binding to its receptor. Furthermore, based on molecular docking and molecular dynamics simulations, metformin was predicted to interact with TGF-β1 at its receptor-binding domain. Single-molecule force spectroscopy revealed that metformin reduces the binding probability but not the binding force of TGF-β1 to its type II receptor. Consequently, metformin suppresses type II TGF-β1 receptor dimerization upon exposure to TGF-β1, which is essential for downstream signal transduction. Thus, our results indicate that metformin is a novel TGF-β suppressor with therapeutic potential for numerous diseases in which TGF-β1 hyperfunction is indicated.

  20. Transforming Growth Factor β Drives Hemogenic Endothelium Programming and the Transition to Hematopoietic Stem Cells.

    PubMed

    Monteiro, Rui; Pinheiro, Philip; Joseph, Nicola; Peterkin, Tessa; Koth, Jana; Repapi, Emmanouela; Bonkhofer, Florian; Kirmizitas, Arif; Patient, Roger

    2016-08-22

    Hematopoietic stem cells (HSCs) are self-renewing multipotent stem cells that generate mature blood lineages throughout life. They, together with hematopoietic progenitor cells (collectively known as HSPCs), emerge from hemogenic endothelium in the floor of the embryonic dorsal aorta by an endothelial-to-hematopoietic transition (EHT). Here we demonstrate that transforming growth factor β (TGFβ) is required for HSPC specification and that it regulates the expression of the Notch ligand Jagged1a in endothelial cells prior to EHT, in a striking parallel with the epithelial-to-mesenchymal transition (EMT). The requirement for TGFβ is two fold and sequential: autocrine via Tgfβ1a and Tgfβ1b produced in the endothelial cells themselves, followed by a paracrine input of Tgfβ3 from the notochord, suggesting that the former programs the hemogenic endothelium and the latter drives EHT. Our findings have important implications for the generation of HSPCs from pluripotent cells in vitro.

  1. Gene polymorphism in transforming growth factor-beta codon 10 is associated with susceptibility to Giardiasis.

    PubMed

    Taherkhani, H; Hajilooi, M; Fallah, M; Khyabanchi, O; Haidari, M

    2009-12-01

    Secretory immunoglobulin A (S-IgA) antibodies have a central role in anti-Giardial defence. It has been demonstrated that transforming growth factor-beta1 (TGF-beta1) stimulates B lymphocytes to produce and secrete S-IgA. We sought to determine the association between TGF-beta1 polymorphism (T+869C) with susceptibility to Giardiasis. The TGF-beta1 genotypes and levels of salivary (S-IgA) were analysed in individuals with Giardiasis (97 symptomatic and 57 asymptomatic) and controls (n = 92). Individuals with symptomatic Giardiasis had the lowest levels of S-IgA compared to individuals in asymptomatic Giardiasis and control groups (97%, 73% and 43%, <1 g L(-1), respectively, P = 0.002). The frequency of allele C and CC genotypes of TGF-beta1 polymorphism was significantly higher among symptomatic patients than asymptomatic and control groups. Logistic regression analysis demonstrated that the individuals homozygous for allele C of TGF-beta1 had a significantly higher risk for symptomatic Giardiasis with odds ratio of 2.76 (95% CI: 3.88, 1.71, P = 0.007). Among the participants with TT genotype per cent of individuals with S-IgA level of more than 1 g L(-1) was almost twice the percentage in CC genotype individuals (14% versus 7% respectively P = 0.01). Our data suggest that CC genotype of TGF-beta1 polymorphism at codon 10 is associated with occurrence of Giardiasis.

  2. Transforming growth factor-β1 in carcinogenesis, progression, and therapy in cervical cancer.

    PubMed

    Zhu, Haiyan; Luo, Hui; Shen, Zhaojun; Hu, Xiaoli; Sun, Luzhe; Zhu, Xueqiong

    2016-06-01

    Transforming growth factor β1 (TGF-β1) is a multifunctional cytokine that plays important roles in cervical tumor formation, invasion, progression, and metastasis. TGF-β1 functions as a tumor inhibitor in precancerous lesions and early stage cancers of cervix whereas as a tumor promoter in later stage. This switch from a tumor inhibitor to a tumor promoter might be due to various alterations in TGF-β signaling pathway, such as mutations or loss of expression of TGF-β receptors and SMAD proteins. Additionally, the oncoproteins of human papillomaviruses have been shown to stimulate TGF-β1 expression, which in turn suppresses host immune surveillance. Thus, in addition to driving tumor cell migration and metastasis, TGF-β1 is believed to play a key role in promoting human papillomavirus infection by weakening host immune defense. In this article, we will discuss the role of TGF-β1 in the expression, carcinogenesis, progression, and therapy in cervical cancers. A better understanding of this cytokine in cervical carcinogenesis is essential for critical evaluation of this cytokine as a potential prognostic marker and therapeutic target.

  3. SV40 transformation of Swiss 3T3 cells can cause a stable reduction in the calcium requirement for growth

    PubMed Central

    1984-01-01

    A well-characterized SV40-transformed Swiss 3T3 line, SV101, and its revertants were tested for the ability to grow in reduced Ca++ (0.01 mM). Transformants and revertants did not differ from the parent 3T3 line in their Ca++ requirements. All three classes of cells grew less well in low Ca++ than in regular Ca++ (2.0 mM). SV40 transformants were then selected for the ability to grow in reduced Ca++. This new class of transformants was found to grow in 1% serum, grow in soft agarose, have a reorganized actin cytoskeleton, and express viral T antigens, as well as grow well in low Ca++. One of the selected clones was found to be T antigen-negative, yet was transformed in the serum, anchorage, actin, and Ca++ assays. It is possible that this clone was a spontaneous transformant. However, Southern blot analysis revealed the presence of integrated SV40 DNA. In addition, this analysis revealed the absence of an intact early region fragment, which codes for the viral T antigens. One explanation of this result may be that the mechanism of viral transformation for growth in low Ca++ involves viral- host DNA interactions that may not require a fully functional T antigen. In this case SV40 integration may be acting as a nonspecific cellular mutagen. PMID:6094595

  4. Ionizing radiation predisposes nonmalignant human mammary epithelial cells to undergo transforming growth factor beta induced epithelial to mesenchymal transition.

    PubMed

    Andarawewa, Kumari L; Erickson, Anna C; Chou, William S; Costes, Sylvain V; Gascard, Philippe; Mott, Joni D; Bissell, Mina J; Barcellos-Hoff, Mary Helen

    2007-09-15

    Transforming growth factor beta1 (TGFbeta) is a tumor suppressor during the initial stage of tumorigenesis, but it can switch to a tumor promoter during neoplastic progression. Ionizing radiation (IR), both a carcinogen and a therapeutic agent, induces TGFbeta activation in vivo. We now show that IR sensitizes human mammary epithelial cells (HMEC) to undergo TGFbeta-mediated epithelial to mesenchymal transition (EMT). Nonmalignant HMEC (MCF10A, HMT3522 S1, and 184v) were irradiated with 2 Gy shortly after attachment in monolayer culture or treated with a low concentration of TGFbeta (0.4 ng/mL) or double treated. All double-treated (IR + TGFbeta) HMEC underwent a morphologic shift from cuboidal to spindle shaped. This phenotype was accompanied by a decreased expression of epithelial markers E-cadherin, beta-catenin, and ZO-1, remodeling of the actin cytoskeleton, and increased expression of mesenchymal markers N-cadherin, fibronectin, and vimentin. Furthermore, double treatment increased cell motility, promoted invasion, and disrupted acinar morphogenesis of cells subsequently plated in Matrigel. Neither radiation nor TGFbeta alone elicited EMT, although IR increased chronic TGFbeta signaling and activity. Gene expression profiling revealed that double-treated cells exhibit a specific 10-gene signature associated with Erk/mitogen-activated protein kinase (MAPK) signaling. We hypothesized that IR-induced MAPK activation primes nonmalignant HMEC to undergo TGFbeta-mediated EMT. Consistent with this, Erk phosphorylation was transiently induced by irradiation and persisted in irradiated cells treated with TGFbeta, and treatment with U0126, a MAP/Erk kinase (MEK) inhibitor, blocked the EMT phenotype. Together, these data show that the interactions between radiation-induced signaling pathways elicit heritable phenotypes that could contribute to neoplastic progression.

  5. GSK3 inactivation is involved in mitochondrial complex IV defect in transforming growth factor (TGF) {beta}1-induced senescence

    SciTech Connect

    Byun, Hae-Ok; Jung, Hyun-Jung; Seo, Yong-Hak; Lee, Young-Kyoung; Hwang, Sung-Chul; Seong Hwang, Eun; Yoon, Gyesoon

    2012-09-10

    Transforming growth factor {beta}1 (TGF {beta}1) induces Mv1Lu cell senescence by persistently producing mitochondrial reactive oxygen species (ROS) through decreased complex IV activity. Here, we investigated the molecular mechanism underlying the effect of TGF {beta}1 on mitochondrial complex IV activity. TGF {beta}1 progressively phosphorylated the negative regulatory sites of both glycogen synthase kinase 3 (GSK3) {alpha} and {beta}, corresponding well to the intracellular ROS generation profile. Pre-treatment of N-acetyl cysteine, an antioxidant, did not alter this GSK3 phosphorylation (inactivation), whereas pharmacological inhibition of GSK3 by SB415286 significantly increased mitochondrial ROS, implying that GSK3 phosphorylation is an upstream event of the ROS generation. GSK3 inhibition by SB415286 decreased complex IV activity and cellular O{sub 2} consumption rate and eventually induced senescence of Mv1Lu cell. Similar results were obtained with siRNA-mediated knockdown of GSK3. Moreover, we found that GSK3 not only exists in cytosol but also in mitochondria of Mv1Lu cell and the mitochondrial GSK3 binds complex IV subunit 6b which has no electron carrier and is topologically located in the mitochondrial intermembrane space. Involvement of subunit 6b in controlling complex IV activity and overall respiration rate was proved with siRNA-mediated knockdown of subunit 6b. Finally, TGF {beta}1 treatment decreased the binding of the subunit 6b to GSK3 and subunit 6b phosphorylation. Taken together, our results suggest that GSK3 inactivation is importantly involved in TGF {beta}1-induced complex IV defects through decreasing phosphorylation of the subunit 6b, thereby contributing to senescence-associated mitochondrial ROS generation.

  6. Environmental Particulate (PM2.5) Augments Stiffness-Induced Alveolar Epithelial Cell Mechanoactivation of Transforming Growth Factor Beta

    PubMed Central

    Dysart, Marilyn M.; Galvis, Boris R.; Russell, Armistead G.; Barker, Thomas H.

    2014-01-01

    Dysfunctional pulmonary homeostasis and repair, including diseases such as pulmonary fibrosis (PF), chronic obstructive pulmonary disease (COPD), and tumorigenesis have been increasing over the past decade, a fact that heavily implicates environmental influences. Several investigations have suggested that in response to increased transforming growth factor - beta (TGFβ) signaling, the alveolar type II (ATII) epithelial cell undergoes phenotypic changes that may contribute to the complex pathobiology of PF. We have previously demonstrated that increased tissue stiffness associated with PF is a potent extracellular matrix (ECM) signal for epithelial cell activation of TGFβ. The work reported here explores the relationship between tissue stiffness and exposure to environmental stimuli in the activation of TGFβ. We hypothesized that exposure of ATII cells to fine particulate matter (PM2.5) will result in enhanced cell contractility, TGFβ activation, and subsequent changes to ATII cell phenotype. ATII cells were cultured on increasingly stiff substrates with or without addition of PM2.5. Exposure to PM2.5 resulted in increased activation of TGFβ, increased cell contractility, and elongation of ATII cells. Most notably, on 8 kPa substrates, a stiffness greater than normal but less than established fibrotic lung, addition of PM2.5 resulted in increased cortical cell stiffness, enhanced actin staining and cell elongation; a result not seen in the absence of PM2.5. Our work suggests that PM2.5 exposure additionally enhances the existing interaction between ECM stiffness and TGFβ that has been previously reported. Furthermore, we show that this additional enhancement is likely a consequence of intracellular reactive oxygen species (ROS) leading to increased TGFβ signaling events. These results highlight the importance of both the micromechanical and biochemical environment in lung disease initiation and suggest that individuals in early stages of lung remodeling

  7. Endotoxin-induced endothelial fibrosis is dependent on expression of transforming growth factors β1 and β2.

    PubMed

    Echeverría, César; Montorfano, Ignacio; Tapia, Pablo; Riedel, Claudia; Cabello-Verrugio, Claudio; Simon, Felipe

    2014-09-01

    During endotoxemia-induced inflammatory disease, bacterial endotoxins circulate in the bloodstream and interact with endothelial cells (ECs), inducing dysfunction of the ECs. We previously reported that endotoxins induce the conversion of ECs into activated fibroblasts. Through endotoxin-induced endothelial fibrosis, ECs change their morphology and their protein expression pattern, thereby suppressing endothelial markers and upregulating fibrotic proteins. The most commonly used fibrotic inducers are transforming growth factor β1 (TGF-β1) and TGF-β2. However, whether TGF-β1 and TGF-β2 participate in endotoxin-induced endothelial fibrosis remains unknown. We have shown that the endotoxin-induced endothelial fibrosis process is dependent on the TGF-β receptor, ALK5, and the activation of Smad3, a protein that is activated by ALK5 activation, thus suggesting that endotoxin elicits TGF-β production to mediate endotoxin-induced endothelial fibrosis. Therefore, we investigated the dependence of endotoxin-induced endothelial fibrosis on the expression of TGF-β1 and TGF-β2. Endotoxin-treated ECs induced the expression and secretion of TGF-β1 and TGF-β2. TGF-β1 and TGF-β2 downregulation inhibited the endotoxin-induced changes in the endothelial marker VE-cadherin and in the fibrotic proteins α-SMA and fibronectin. Thus, endotoxin induces the production of TGF-β1 and TGF-β2 as a mechanism to promote endotoxin-induced endothelial fibrosis. To the best of our knowledge, this is the first report showing that endotoxin induces endothelial fibrosis via TGF-β secretion, which represents an emerging source of vascular dysfunction. These findings contribute to understanding the molecular mechanism of endotoxin-induced endothelial fibrosis, which could be useful in the treatment of inflammatory diseases.

  8. Human T-cell leukemia virus type 2 tax mutants that selectively abrogate NFkappaB or CREB/ATF activation fail to transform primary human T cells.

    PubMed

    Ross, T M; Narayan, M; Fang, Z Y; Minella, A C; Green, P L

    2000-03-01

    Human T-cell leukemia virus (HTLV) Tax protein has been implicated in the HTLV oncogenic process, primarily due to its pleiotropic effects on cellular genes involved in growth regulation and cell cycle control. To date, several approaches attempting to correlate Tax activation of the CREB/activating transcription factor (ATF) or NFkappaB/Rel transcriptional activation pathway to cellular transformation have yielded conflicting results. In this study, we use a unique HTLV-2 provirus (HTLV(c-enh)) that replicates by a Tax-independent mechanism to directly assess the role of Tax transactivation in HTLV-mediated T-lymphocyte transformation. A panel of well-characterized tax-2 mutations is utilized to correlate the respective roles of the CREB/ATF or NFkappaB/Rel signaling pathway. Our results demonstrate that viruses expressing tax-2 mutations that selectively abrogate NFkappaB/Rel or CREB/ATF activation display distinct phenotypes but ultimately fail to transform primary human T lymphocytes. One conclusion consistent with our results is that the activation of NFkappaB/Rel provides a critical proliferative signal early in the cellular transformation process, whereas CREB/ATF activation is required to promote the fully transformed state. However, complete understanding will require correlation of Tax domains important in cellular transformation to those Tax domains important in the modulation of gene transcription, cell cycle control, induction of DNA damage, and other undefined activities.

  9. Differential occurrence of CSF-like activity and transforming activity of Mos during the cell cycle in fibroblasts.

    PubMed Central

    Okazaki, K; Nishizawa, M; Furuno, N; Yasuda, H; Sagata, N

    1992-01-01

    The Xenopus c-mos proto-oncogene product, Mosxe, possesses cytostatic factor (CSF) activity to arrest maturing oocytes in metaphase II and has weak transforming activity in mouse NIH3T3 cells. We show that Mosxe mutants bearing 'stabilizing' penultimate N-terminal amino acids are strongly transforming and can retard progression through the G2-M phases in Mosxe-transformed cells, probably via their CSF activity. On the other hand, a cyclin-Mosxe fusion protein, which undergoes abrupt degradation at the end of mitosis and is restored to its normal levels only after the G1 phase, transforms cells much less efficiently than a mutated cyclin-Mosxe fusion protein that is stable during M-G1 transition. Moreover, in low-serum medium, cells transformed by the unstable cyclin-Mosxe require a long period to enter the S phase, in contrast with the rapid entry into the S phase of cells transformed by the stable cyclin-Mosxe. These results provide strong evidence that unlike the physiological CSF activity, the transforming activity of Mos is exerted in the G1 phase of the cell cycle. Images PMID:1385775

  10. A Role for Endogenous Transforming Growth Factor β1 in Langerhans Cell Biology:  The Skin of   Transforming Growth Factor β1 Null Mice Is Devoid of  Epidermal Langerhans Cells

    PubMed Central

    Borkowski, Teresa A.; Letterio, John J.; Farr, Andrew G.; Udey, Mark C.

    1996-01-01

    Transforming growth factor β1 (TGF-β1) regulates leukocytes and epithelial cells. To determine whether the pleiotropic effects of TGF-β1, a cytokine that is produced by both keratinocytes and Langerhans cells (LC), extend to epidermal leukocytes, we characterized LC (the epidermal contingent of the dendritic cell [DC] lineage) and dendritic epidermal T cells (DETC) in TGF-β1 null (TGF-β1 −/−) mice. I-A+ LC were not detected in epidermal cell suspensions or epidermal sheets prepared from TGF-β1 −/− mice, and epidermal cell suspensions were devoid of allostimulatory activity. In contrast, TCR-γδ+ DETC were normal in number and appearance in TGF-β1 −/− mice and, importantly, DETC represented the only leukocytes in the epidermis. Immunolocalization studies revealed CD11c+ DC in lymph nodes from TGF-β1 −/− mice, although gp40+ DC were absent. Treatment of TGF-β1 −/− mice with rapamycin abrogated the characteristic inflammatory wasting syndrome and prolonged survival indefinitely, but did not result in population of the epidermis with LC. Thus, the LC abnormality in TGF-β1 −/− mice is not a consequence of inflammation in skin or other organs, and LC development is not simply delayed in these animals. We conclude that endogenous TGF-β1 is essential for normal murine LC development or epidermal localization. PMID:8976197

  11. Renal (pro)renin receptor contributes to development of diabetic kidney disease through transforming growth factor-β1-connective tissue growth factor signalling cascade.

    PubMed

    Huang, Jiqian; Matavelli, Luis C; Siragy, Helmy M

    2011-04-01

    1. Transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) are expressed in renal glomeruli, and contribute to the development of diabetic nephropathy. Recently, we showed that (pro)renin receptor (PRR) is upregulated in the kidneys of the streptozocin (STZ)-induced diabetes rat model. We hypothesized that in the presence of hyperglycaemia, increased renal PRR expression contributes to enhanced TGF-β1-CTGF signalling activity, leading to the development of diabetic kidney disease. 2. In vivo and in vitro studies were carried out in Sprague-Dawley rats and rat mesangial cells (RMC). PRR blockade was achieved in vivo by treating STZ induced diabetes rats with the handle region peptide (HRP) of prorenin and in vitro by HRP or PRR siRNA in RMC. Angiotensin AT1 receptor blockade was achieved by valsartan treatment. 3. Results showed that expression of PRR, TGF-β1 and CTGF were upregulated in diabetic kidneys and RMC exposed to high glucose. Glucose exposure also induced PRR phosphorylation, a process that was inhibited by HRP, valsartan or PRR siRNA. HRP and valsartan significantly attenuated renal TGF-β1 and CTGF expression in diabetic animals and high glucose treated RMC. Similar results were observed in high glucose exposed RMC in response to PRR siRNA. TGF-β receptor blockade decreased CTGF expression in RMC. Combined administration of valsartan and PRR siRNA showed further reduction of TGF-β1 and CTGF expression in RMC. 4. In conclusion, PRR contributes to kidney disease in diabetes through an enhanced TGF-β1-CTGF signalling cascade.

  12. Transforming Growth Factor-β1 Downregulates Vascular Endothelial Growth Factor-D Expression in Human Lung Fibroblasts via the Jun NH2-Terminal Kinase Signaling Pathway

    PubMed Central

    Cui, Ye; Osorio, Juan C; Risquez, Cristobal; Wang, Hao; Shi, Ying; Gochuico, Bernadette R; Morse, Danielle; Rosas, Ivan O; El-Chemaly, Souheil

    2014-01-01

    Vascular endothelial growth factor (VEGF)-D, a member of the VEGF family, induces both angiogenesis and lymphangiogenesis by activating VEGF receptor-2 (VEGFR-2) and VEGFR-3 on the surface of endothelial cells. Transforming growth factor (TGF)-β1 has been shown to stimulate VEGF-A expression in human lung fibroblast via the Smad3 signaling pathway and to induce VEGF-C in human proximal tubular epithelial cells. However, the effects of TGF-β1 on VEGF-D regulation are unknown. To investigate the regulation of VEGF-D, human lung fibroblasts were studied under pro-fibrotic conditions in vitro and in idiopathic pulmonary fibrosis (IPF) lung tissue. We demonstrate that TGF-β1 downregulates VEGF-D expression in a dose- and time-dependent manner in human lung fibroblasts. This TGF-β1 effect can be abolished by inhibitors of TGF-β type I receptor kinase and Jun NH2-terminal kinase (JNK), but not by Smad3 knockdown. In addition, VEGF-D knockdown in human lung fibroblasts induces G1/S transition and promotes cell proliferation. Importantly, VEGF-D protein expression is decreased in lung homogenates from IPF patients compared with control lung. In IPF lung sections, fibroblastic foci show very weak VEGF-D immunoreactivity, whereas VEGF-D is abundantly expressed within alveolar interstitial cells in control lung. Taken together, our data identify a novel mechanism for downstream signal transduction induced by TGF-β1 in lung fibroblasts, through which they may mediate tissue remodeling in IPF. PMID:24515257

  13. How consumer physical activity monitors could transform human physiology research.

    PubMed

    Wright, Stephen P; Hall Brown, Tyish S; Collier, Scott R; Sandberg, Kathryn

    2017-03-01

    A sedentary lifestyle and lack of physical activity are well-established risk factors for chronic disease and adverse health outcomes. Thus, there is enormous interest in measuring physical activity in biomedical research. Many consumer physical activity monitors, including Basis Health Tracker, BodyMedia Fit, DirectLife, Fitbit Flex, Fitbit One, Fitbit Zip, Garmin Vivofit, Jawbone UP, MisFit Shine, Nike FuelBand, Polar Loop, Withings Pulse O2, and others have accuracies similar to that of research-grade physical activity monitors for measuring steps. This review focuses on the unprecedented opportunities that consumer physical activity monitors offer for human physiology and pathophysiology research because of their ability to measure activity continuously under real-life conditions and because they are already widely used by consumers. We examine current and potential uses of consumer physical activity monitors as a measuring or monitoring device, or as an intervention in strategies to change behavior and predict health outcomes. The accuracy, reliability, reproducibility, and validity of consumer physical activity monitors are reviewed, as are limitations and challenges associated with using these devices in research. Other topics covered include how smartphone apps and platforms, such as the Apple ResearchKit, can be used in conjunction with consumer physical activity monitors for research. Lastly, the future of consumer physical activity monitors and related technology is considered: pattern recognition, integration of sleep monitors, and other biosensors in combination with new forms of information processing.

  14. Mutations in the Polybasic Juxtamembrane Sequence of Both Plasma Membrane- and Endoplasmic Reticulum-localized Epidermal Growth Factor Receptors Confer Ligand-independent Cell Transformation*

    PubMed Central

    Bryant, Kirsten L.; Antonyak, Marc A.; Cerione, Richard A.; Baird, Barbara; Holowka, David

    2013-01-01

    Deregulation of ErbB receptor-tyrosine kinases is a hallmark of many human cancers. Conserved in the ErbB family is a cluster of basic amino acid residues in the cytoplasmic juxtamembrane region. We found that charge-silencing mutagenesis within this juxtamembrane region of the epidermal growth factor receptor (EGFR) results in the generation of a mutant receptor (EGFR Mut R1-6) that spontaneously transforms NIH 3T3 cells in a ligand-independent manner. A similar mutant with one additional basic residue, EGFR Mut R1-5, fails to exhibit ligand-independent transformation. The capacity of EGFR Mut R1-6 to mediate this transformation is maintained when this mutant is retained in the endoplasmic reticulum via a single point mutation, L393H, which we describe. We show that EGFR Mut R1-6 with or without L393H exhibits enhanced basal tyrosine phosphorylation when ectopically expressed, and the ligand-independent transforming activity of EGFR Mut R1-6 is sensitive to inhibition of EGFR kinase activity and is particularly dependent on PI3K and mTOR activity. Similar to EGFR Mut R1-6/L393H in NIH 3T3 cells, EGFR variant type III, a highly oncogenic mutant form of EGFR linked to human brain cancers, confers transforming activity while it is wholly endoplasmic reticulum-retained in U87 cells. Our findings highlight the importance of the polybasic juxtamembrane sequence in regulating the oncogenic potential of EGFR signaling. PMID:24142702

  15. Physiological adaptation of growth kinetics in activated sludge.

    PubMed

    Friedrich, M; Takács, I; Tränckner, J

    2015-11-15

    Physiological adaptation as it occurs in bacterial cells at variable environmental conditions influences characteristic properties of growth kinetics significantly. However, physiological adaptation to growth related parameters in activated sludge modelling is not yet recognised. Consequently these parameters are regarded to be constant. To investigate physiological adaptation in activated sludge the endogenous respiration in an aerobic degradation batch experiment and simultaneous to that the maximum possible respiration in an aerobic growth batch experiment was measured. The activated sludge samples were taken from full scale wastewater treatment plants with different sludge retention times (SRTs). It could be shown that the low SRT sludge adapts by growth optimisation (high maximum growth rate and high decay rate) to its particular environment where a high SRT sludge adapts by survival optimization (low maximum growth rate and low decay rate). Thereby, both the maximum specific growth rate and the decay rate vary in the same pattern and are strongly correlated to each other. To describe the physiological state of mixed cultures like activated sludge quantitatively a physiological state factor (PSF) is proposed as the ratio of the maximum specific growth rate and the decay rate. The PSF can be expressed as an exponential function with respect to the SRT.

  16. Quantitative structure-activity relationship models of chemical transformations from matched pairs analyses.

    PubMed

    Beck, Jeremy M; Springer, Clayton

    2014-04-28

    The concepts of activity cliffs and matched molecular pairs (MMP) are recent paradigms for analysis of data sets to identify structural changes that may be used to modify the potency of lead molecules in drug discovery projects. Analysis of MMPs was recently demonstrated as a feasible technique for quantitative structure-activity relationship (QSAR) modeling of prospective compounds. Although within a small data set, the lack of matched pairs, and the lack of knowledge about specific chemical transformations limit prospective applications. Here we present an alternative technique that determines pairwise descriptors for each matched pair and then uses a QSAR model to estimate the activity change associated with a chemical transformation. The descriptors effectively group similar transformations and incorporate information about the transformation and its local environment. Use of a transformation QSAR model allows one to estimate the activity change for novel transformations and therefore returns predictions for a larger fraction of test set compounds. Application of the proposed methodology to four public data sets results in increased model performance over a benchmark random forest and direct application of chemical transformations using QSAR-by-matched molecular pairs analysis (QSAR-by-MMPA).

  17. Adolescents' Accounts of Growth Experiences in Youth Activities.

    ERIC Educational Resources Information Center

    Dworkin, Jodi B.; Larson, Reed; Hansen, David

    2003-01-01

    Conducted 10 focus groups in which adolescents discussed their "growth experiences" in extracurricular and community-based activities. The 55 participants reported personal and interpersonal processes and generally described themselves as agents of their own development and change. (SLD)

  18. Protein Crystal Growth Activities on STS-42

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Protein Crystal Growth (PCG) middeck payload is currently manifested to fly on STS-42 in January 1992. This payload is a joint effort between NASA s Office of Commercial Programs (OCP) and Office of Space Science and Applications (OSSA). The PCG experiments are managed by the Center for Macromolecular Crystallography (CMC), a NASA Center for the Commercial Development of Space (CCDS) based at the University of Alabama at Birmingham (UAB). This is the eighth flight of a payload in the PCG program that is jointly sponsored by the OCP and the OSSA. The flight hardware for STS-42 includes six Vapor Diffusion Apparatus (VDA) trays stored in two Refrigerator/Incubator Modules (R/TM s). The VDA trays will simultaneously conduct 120 experiments involving 15 different protein compounds, four of which are sponsored by the OCP, the UAB CCDS, and four co-investigators.

  19. Breadboard activities for advanced protein crystal growth

    NASA Technical Reports Server (NTRS)

    Rosenberger, Franz; Banish, Michael

    1993-01-01

    The proposed work entails the design, assembly, testing, and delivery of a turn-key system for the semi-automated determination of protein solubilities as a function of temperature. The system will utilize optical scintillation as a means of detecting and monitoring nucleation and crystallite growth during temperature lowering (or raising, with retrograde solubility systems). The deliverables of this contract are: (1) turn-key scintillation system for the semi-automatic determination of protein solubilities as a function of temperature, (2) instructions and software package for the operation of the scintillation system, and (3) one semi-annual and one final report including the test results obtained for ovostatin with the above scintillation system.

  20. Transforming Growth Factor β/activin signalling induces epithelial cell flattening during Drosophila oogenesis

    PubMed Central

    Brigaud, Isabelle; Duteyrat, Jean-Luc; Chlasta, Julien; Le Bail, Sandrine; Couderc, Jean-Louis; Grammont, Muriel

    2015-01-01

    ABSTRACT Although the regulation of epithelial morphogenesis is essential for the formation of tissues and organs in multicellular organisms, little is known about how signalling pathways control cell shape changes in space and time. In the Drosophila ovarian epithelium, the transition from a cuboidal to a squamous shape is accompanied by a wave of cell flattening and by the ordered remodelling of E-cadherin-based adherens junctions. We show that activation of the TGFβ pathway is crucial to determine the timing, the degree and the dynamic of cell flattening. Within these cells, TGFβ signalling controls cell-autonomously the formation of Actin filament and the localisation of activated Myosin II, indicating that internal forces are generated and used to remodel AJ and to promote cytoskeleton rearrangement. Our results also reveal that TGFβ signalling controls Notch activity and that its functions are partly executed through Notch. Thus, we demonstrate that the cells that undergo the cuboidal-to-squamous transition produce active cell-shaping mechanisms, rather than passively flattening in response to a global force generated by the growth of the underlying cells. Thus, our work on TGFβ signalling provides new insights into the mechanisms through which signal transduction cascades orchestrate cell shape changes to generate proper organ structure. PMID:25681395

  1. Transforming Growth Factor β/activin signalling induces epithelial cell flattening during Drosophila oogenesis.

    PubMed

    Brigaud, Isabelle; Duteyrat, Jean-Luc; Chlasta, Julien; Le Bail, Sandrine; Couderc, Jean-Louis; Grammont, Muriel

    2015-02-13

    Although the regulation of epithelial morphogenesis is essential for the formation of tissues and organs in multicellular organisms, little is known about how signalling pathways control cell shape changes in space and time. In the Drosophila ovarian epithelium, the transition from a cuboidal to a squamous shape is accompanied by a wave of cell flattening and by the ordered remodelling of E-cadherin-based adherens junctions. We show that activation of the TGFβ pathway is crucial to determine the timing, the degree and the dynamic of cell flattening. Within these cells, TGFβ signalling controls cell-autonomously the formation of Actin filament and the localisation of activated Myosin II, indicating that internal forces are generated and used to remodel AJ and to promote cytoskeleton rearrangement. Our results also reveal that TGFβ signalling controls Notch activity and that its functions are partly executed through Notch. Thus, we demonstrate that the cells that undergo the cuboidal-to-squamous transition produce active cell-shaping mechanisms, rather than passively flattening in response to a global force generated by the growth of the underlying cells. Thus, our work on TGFβ signalling provides new insights into the mechanisms through which signal transduction cascades orchestrate cell shape changes to generate proper organ structure.

  2. The pathogenic role of transforming growth factor-β2 in glaucomatous damage to the optic nerve head.

    PubMed

    Fuchshofer, Rudolf

    2011-08-01

    In patients with primary open angle glaucoma (POAG), the optic nerve head (ONH) shows characteristic cupping correlated with visual field defects. The progressive optic neuropathy is characterized by irreversible loss of retinal ganglion cells (RGC). The critical risk factor for axonal damage at the ONH is an elevated intraocular pressure (IOP). The increase in IOP correlates with axonal loss in the ONH, which might be due to an impaired axoplasmatic flow leading to the loss of RGCs. Damage to the optic nerve is thought to occur in the lamina cribrosa (LC) region of the ONH, which is composed of characteristic sieve-like connective tissue cribriform plates through which RGC axons exit the eye. The cupping of the optic disc, and the compression and excavation of LC are characteristic signs of glaucomatous ONH remodelling. In ONH of POAG patients a disorganized distribution and deposition of elastic fibers and a typical pronounced thickening of the connective tissue septae surrounding the optic nerve fibers is found. Transforming growth factor (TGF)-β2 could be one of the pathogenic factors responsible for the structural alterations in POAG patients as the TGF-β2 levels in the ONH of glaucomatous eyes are elevated as well as in the aqueous homour. TGF-β2 leads to an increased synthesis of extracellular matrix (ECM) molecules mediated by connective tissue growth factor and to an impaired ECM degradation in cultured ONH astrocytes. Bone morphogenetic protein (BMP)-4 effectively antagonizes the effects of TGF-β2 on matrix deposition. The BMP antagonist gremlin blocks this inhibition, allowing TGF-β2 stimulation of ECM synthesis. Overall, the ECM in the ONH is kept in balance in the OHN by factors that augment or block the activity of TGF-β2.

  3. Effects of transforming growth factor type beta on expression of cytoskeletal proteins in endosteal mouse osteoblastic cells

    SciTech Connect

    Lomri, A.; Marie, P.J. )

    1990-01-01

    Transforming growth factor beta (TGF beta) has been shown to influence the growth and differentiation of many cell types in vitro. We have examined the effects of TGF beta on cell morphology and cytoskeletal organization in relation to parameters of cell proliferation and differentiation in endosteal osteoblastic cells isolated from mouse caudal vertebrae. Treatment of mouse osteoblastic cells cultured in serum free medium for 24 hours with TGF beta (1.5-30 ng/mL) slightly (-23%) inhibited alkaline phosphatase activity. In parallel, TGF beta (0.5-30 ng/mL, 24 hours) greatly increased cell replication as evaluated by (3H)-thymidine incorporation into DNA (157% to 325% of controls). At a median dose (1.5 ng/mL) that affected both alkaline phosphatase and DNA synthesis (235% of controls) TGF beta induced rapid (six hours) cell respreading of quiescent mouse osteoblastic cells. This effect was associated with increased polymerization of actin, alpha actinin, and tubulins, as evaluated by both biochemical and immunofluorescence methods. In addition, TGF beta (1.5 ng/mL) increased the de novo biosynthesis of actin, alpha actinin, vimentin, and tubulins, as determined by {sup 35}S methionine labeling and fractionation of cytoskeletal proteins using two-dimensional gel electrophoresis. These effects were rapid and transient, as they occurred at six hours and were reversed after 24 hours of TGF beta exposure. The results indicate that the stimulatory effect of TGF beta on DNA synthesis in endosteal mouse osteoblastic cells is associated with a transient increase in cell spreading associated with enhanced polymerization and synthesis of cytoskeletal proteins.

  4. p70 ribosomal S6 kinase regulates subpleural fibrosis following transforming growth factor-α expression in the lung

    PubMed Central

    Madala, Satish K.; Thomas, George; Edukulla, Ramakrishna; Davidson, Cynthia; Schmidt, Stephanie; Schehr, Angelica

    2015-01-01

    The p70 ribosomal S6 kinase (S6K) is a downstream substrate that is phosphorylated and activated by the mammalian target of rapamycin complex and regulates multiple cellular processes associated with fibrogenesis. Recent studies demonstrate that aberrant mTORC1-S6K signaling contributes to various pathological conditions, but a direct role in pulmonary fibroproliferation has not been established. Increased phosphorylation of the S6K pathway is detected immediately following transforming growth factor-α (TGF-α) expression in a transgenic model of progressive lung fibrosis. To test the hypothesis that the S6K directly regulates pulmonary fibroproliferative disease we determined the cellular sites of S6K phosphorylation during the induction of fibrosis in the TGF-α model and tested the efficacy of specific pharmacological inhibition of the S6K pathway to prevent and reverse fibrotic disease. Following TGF-α expression increased phosphorylation of the S6K was detected in the airway and alveolar epithelium and the mesenchyme of advanced subpleural fibrotic regions. Specific inhibition of the S6K with the small molecule inhibitor LY-2584702 decreased TGF-α and platelet-derived growth factor-β-induced proliferation of lung fibroblasts in vitro. Administration of S6K inhibitors to TGF-α mice prevented the development of extensive subpleural fibrosis and alterations in lung mechanics, and attenuated the increase in total lung hydroxyproline. S6K inhibition after fibrosis was established attenuated the progression of subpleural fibrosis. Together these studies demonstrate targeting the S6K pathway selectively modifies the progression of pulmonary fibrosis in the subpleural compartment of the lung. PMID:26566903

  5. Hydrogen sulfide suppresses transforming growth factor-β1-induced differentiation of human cardiac fibroblasts into myofibroblasts.

    PubMed

    Zhang, YouEn; Wang, JiaNing; Li, Hua; Yuan, LiangJun; Wang, Lei; Wu, Bing; Ge, JunBo

    2015-11-01

    In heart disease, transforming growth factor-β1 (TGF-β1) converts fibroblasts into myofibroblasts, which synthesize and secrete fibrillar type I and III collagens. The purpose of the present study was to investigate how hydrogen sulfide (H2S) suppresses TGF-β1-induced differentiation of human cardiac fibroblasts to myofibroblasts. Human cardiac fibroblasts were serum-starved in fibroblast medium for 16 h before exposure to TGF-β1 (10 ng mL(-1)) for 24 h with or without sodium hydrosulfide (NaHS, 100 µmol L(-1), 30 min pretreatment) treatment. NaHS, an exogenous H2S donor, potently inhibited the proliferation and migration of TGF-β1-induced human cardiac fibroblasts and regulated their cell cycle progression. Furthermore, NaHS treatment led to suppression of fibroblast differentiation into myofibroblasts, and reduced the levels of collagen, TGF-β1, and activated Smad3 in TGF-β1-induced human cardiac fibroblasts in vitro. We therefore conclude that H2S suppresses TGF-β1-stimulated conversion of fibroblasts to myofibroblasts by inhibiting the TGF-β1/Smad3 signaling pathway, as well as by inhibiting the proliferation, migration, and cell cycle progression of human cardiac myofibroblasts. These effects of H2S may play significant roles in cardiac remodeling associated with heart failure.

  6. Angiopoietin-like protein 2 increases renal fibrosis by accelerating transforming growth factor-β signaling in chronic kidney disease.

    PubMed

    Morinaga, Jun; Kadomatsu, Tsuyoshi; Miyata, Keishi; Endo, Motoyoshi; Terada, Kazutoyo; Tian, Zhe; Sugizaki, Taichi; Tanigawa, Hiroki; Zhao, Jiabin; Zhu, Shunshun; Sato, Michio; Araki, Kimi; Iyama, Ken-ichi; Tomita, Kengo; Mukoyama, Masashi; Tomita, Kimio; Kitamura, Kenichiro; Oike, Yuichi

    2016-02-01

    Renal fibrosis is a common pathological consequence of chronic kidney disease (CKD) with tissue fibrosis closely associated with chronic inflammation in numerous pathologies. However, molecular mechanisms underlying that association, particularly in the kidney, remain unclear. Here, we determine whether there is a molecular link between chronic inflammation and tissue fibrosis in CKD progression. Histological analysis of human kidneys indicated abundant expression of angiopoietin-like protein 2 (ANGPTL2) in renal tubule epithelial cells during progression of renal fibrosis. Numerous ANGPTL2-positive renal tubule epithelial cells colocalized with cells positive for transforming growth factor (TGF)-β1, a critical mediator of tissue fibrosis. Analysis of M1 collecting duct cells in culture showed that TGF-β1 increases ANGPTL2 expression by attenuating its repression through microRNA-221. Conversely, ANGPTL2 increased TGF-β1 expression through α5β1 integrin-mediated activation of extracellular signal-regulated kinase. Furthermore, ANGPTL2 deficiency in a mouse unilateral ureteral obstruction model significantly reduced renal fibrosis by decreasing TGF-β1 signal amplification in kidney. Thus, ANGPTL2 and TGF-β1 positively regulate each other as renal fibrosis progresses. Our study provides insight into molecular mechanisms underlying chronic inflammation and tissue fibrosis and identifies potential therapeutic targets for CKD treatment.

  7. Matrix metalloproteinase-8 regulates transforming growth factor-β1 levels in mouse tongue wounds and fibroblasts in vitro.

    PubMed

    Aström, Pirjo; Pirilä, Emma; Lithovius, Riitta; Heikkola, Heidi; Korpi, Jarkko T; Hernández, Marcela; Sorsa, Timo; Salo, Tuula

    2014-10-15

    Matrix metalloproteinase-8 (MMP-8)-deficient mice (Mmp8-/-) exhibit delayed dermal wound healing, but also partly contradicting results have been reported. Using the Mmp8-/- mice we investigated the role of MMP-8 in acute wound healing of the mobile tongue, and analyzed the function of tongue fibroblasts in vitro. Interestingly, in the early phase the tongue wounds of Mmp8-/- mice healed faster than those of wild type (wt) mice resulting in significant difference in wound widths (P=0.001, 6-24h). The Mmp8-/- wounds showed no change in myeloperoxidase positive myeloid cell count, but the level of transforming growth factor (TGF)-β1 was significantly increased (P=0.007) compared to the wt tongues. Fibroblasts cultured from wt tongues expressed MMP-8 and TGF-β1. However, higher TGF-β1 levels were detected in Mmp8-/- fibroblasts, and MMP-8 treatment decreased phosphorylated Smad-2 levels and α-smooth muscle actin expression in these fibroblasts suggesting reduced TGF-β1 signaling. Consistently, a degradation of recombinant TGF-β1 by MMP-8 decreased its ability to activate the signaling cascade in fibroblasts. Moreover, collagen gels with Mmp8-/- fibroblasts reduced more in size. We conclude that MMP-8 regulates tongue wound contraction rate and TGF-β1 levels. In vitro analyses suggest that MMP-8 may also play a role in regulating TGF-β1 signaling of stromal fibroblasts.

  8. Doxazosin Treatment Attenuates Carbon Tetrachloride-Induced Liver Fibrosis in Hamsters through a Decrease in Transforming Growth Factor β Secretion

    PubMed Central

    Muñoz-Ortega, Martin Humberto; Llamas-Ramírez, Raúl Wiliberto; Romero-Delgadillo, Norma Isabel; Elías-Flores, Tania Guadalupe; de Jesus Tavares-Rodríguez, Edgar; del Rosario Campos-Esparza, María; Cervantes-García, Daniel; Muñoz-Fernández, Luis; Gerardo-Rodríguez, Martin; Ventura-Juárez, Javier

    2016-01-01

    Background/Aims The development of therapeutic strategies for the treatment of cirrhosis has become an important focus for basic and clinical researchers. Adrenergic receptor antagonists have been evaluated as antifibrotic drugs in rodent models of carbon tetrachloride (CCl4)-induced cirrhosis. The aim of the present study was to evaluate the effects of carvedilol and doxazosin on fibrosis/cirrhosis in a hamster animal model. Methods Cirrhotic-induced hamsters were treated by daily administration of carvedilol and doxazosin for 6 weeks. Hepatic function and histological evaluation were conducted by measuring biochemical markers, including total bilirubin, aspartate aminotransferase, alanine aminotransferase and albumin, and liver tissue slices. Additionally, transforming growth factor β (TGF-β) immunohistochemistry was analyzed. Results Biochemical markers revealed that hepatic function was restored after treatment with doxazosin and carvedilol. Histological evaluation showed a decrease in collagen type I deposits and TGF-β-secreting cells. Conclusions Taken together, these results suggest that the decrease in collagen type I following treatment with doxazosin or carvedilol is achieved by decreasing the profibrotic activities of TGF-β via the blockage of α1- and β-adrenergic receptor. Consequently, a diminution of fibrotic tissue in the CCl4-induced model of cirrhosis is achieved. PMID:26573293

  9. The G-quadruplex augments translation in the 5' untranslated region of transforming growth factor β2.

    PubMed

    Agarwala, Prachi; Pandey, Satyaprakash; Mapa, Koyeli; Maiti, Souvik

    2013-03-05

    Transforming growth factor β2 (TGFβ2) is a versatile cytokine with a prominent role in cell migration, invasion, cellular development, and immunomodulation. TGFβ2 promotes the malignancy of tumors by inducing epithelial-mesenchymal transition, angiogenesis, and immunosuppression. As it is well-documented that nucleic acid secondary structure can regulate gene expression, we assessed whether any secondary motif regulates its expression at the post-transcriptional level. Bioinformatics analysis predicts an existence of a 23-nucleotide putative G-quadruplex sequence (PG4) in the 5' untranslated region (UTR) of TGFβ2 mRNA. The ability of this stretch of sequence to form a highly stable, intramolecular parallel quadruplex was demonstrated using ultraviolet and circular dichroism spectroscopy. Footprinting studies further validated its existence in the presence of a neighboring nucleotide sequence. Following structural characterization, we evaluated the biological relevance of this secondary motif using a dual luciferase assay. Although PG4 inhibits the expression of the reporter gene, its presence in the context of the entire 5' UTR sequence interestingly enhances gene expression. Mutation or removal of the G-quadruplex sequence from the 5' UTR of the gene diminished the level of expression of this gene at the translational level. Thus, here we highlight an activating role of the G-quadruplex in modulating gene expression of TGFβ2 at the translational level and its potential to be used as a target for the development of therapeutics against cancer.

  10. Accumulation of Extracellular Matrix and Developmental Dysregulation in the Pancreas by Transgenic Production of Transforming Growth Factor-β1

    PubMed Central

    Lee, Myung-Shik; Gu, Danling; Feng, Lili; Curriden, Scott; Arnush, Marc; Krahl, Troy; Gurushanthaiah, Deepak; Wilson, Curtis; Loskutoff, David L.; Fox, Howard; Sarvetnick, Nora

    1995-01-01

    Transgenic mice expressing transforming growth factor-β1 (TGF-β1) in the pancreatic β-islet cells directed by human insulin promoter were produced to study in vivo effects of TGF-β1. Fibroblast proliferation and abnormal deposition of extracellular matrix were observed from birth onward, finally replacing almost all the exocrine pancreas. Cellular infiltrates comprising macrophages and neutrophils were also observed. Plasminogen activator inhibitor was induced in the transgenic pancreas as well as fibronectin and laminin, partly explaining accumulation of extracellular matrix. TGF-β1 inhibited proliferation of acinar cells in vivo as evidenced by decreased bromodeoxyuridine incorporation. Development of pancreatic islets was dysregulated, resulting in small islet cell clusters without formation of normal adult islets; however, the overall islet cell mass was not signfifcantly diminished. Additional transgenic lines with less pronounced phenotypes had less expression of TGF-β1 transgene. These findings suggest that TGF-β1 might be a mediator of diseases associated with extracellular matrix deposition such as chronic pancreatitis, and this mouse model will be useful for further analysis of the in vivo effects of TGF-β1, including its potential for immunosuppression. Imagesp43-aFigure 2Figure 3Figure 4Figure 5Figure 6 PMID:7604884

  11. Circulating transforming growth factor-β1 levels and the risk for kidney disease in African-Americans

    PubMed Central

    Suthanthiran, Manikkam; Gerber, Linda M.; Schwartz, Joseph E.; Sharma, Vijay K.; Medeiros, Mara; Marion, RoseMerie; Pickering, Thomas G.; August, Phyllis

    2013-01-01

    Transforming growth factor-β1 (TGF-β1) is well known to induce progression of experimental renal disease. Here we determined whether there is an association between serum levels of TGF-β1 and the risk factors for progression of clinically relevant renal disorders in 186 black and 147 white adults none of whom had kidney disease or diabetes. Serum TGF-β1 protein levels were positively and significantly associated with plasma renin activity along with the systolic and diastolic blood pressure in blacks but not whites after controlling for age, gender and body mass index. These TGF-β1 protein levels were also significantly associated with body mass index and metabolic syndrome and more predictive of microalbuminuria in blacks than in whites. The differential association between TGF-β1 and renal disease risk factors in blacks and whites suggests an explanation for the excess burden of end-stage renal disease in the black population but this requires validation in an independent cohort. Whether these findings show that it is the circulating levels of TGF-β1 that contributes to renal disease progression or reflects other unmeasured factors will need to be tested in longitudinal studies. PMID:19279557

  12. The kinases MEKK2 and MEKK3 regulate transforming growth factor-β-mediated helper T cell differentiation.

    PubMed

    Chang, Xing; Liu, Fang; Wang, Xiaofang; Lin, Aiping; Zhao, Hongyu; Su, Bing

    2011-02-25

    Mitogen-activated protein kinases (MAPKs) are key mediators of the T cell receptor (TCR) signals but their roles in T helper (Th) cell differentiation are unclear. Here we showed that the MAPK kinase kinases MEKK2 (encoded by Map3k2) and MEKK3 (encoded by Map3k3) negatively regulated transforming growth factor-β (TGF-β)-mediated Th cell differentiation. Map3k2(-/-)Map3k3(Lck-Cre/-) mice showed an abnormal accumulation of regulatory T (Treg) and Th17 cells in the periphery, consistent with Map3k2(-/-)Map3k3(Lck-Cre/-) naive CD4(+) T cells' differentiation into Treg and Th17 cells with a higher frequency than wild-type (WT) cells after TGF-β stimulation in vitro. In addition, Map3k2(-/-)Map3k3(Lck-Cre/-) mice developed more severe experimental autoimmune encephalomyelitis. Map3k2(-/-)Map3k3(Lck-Cre/-) T cells exhibited impaired phosphorylation of SMAD2 and SMAD3 proteins at their linker regions, which negatively regulated the TGF-β responses in T cells. Thus, the crosstalk between TCR-induced MAPK and the TGF-β signaling pathways is important in regulating Th cell differentiation.

  13. Pin1 down-regulates transforming growth factor-beta (TGF-beta) signaling by inducing degradation of Smad proteins.

    PubMed

    Nakano, Ayako; Koinuma, Daizo; Miyazawa, Keiji; Uchida, Takafumi; Saitoh, Masao; Kawabata, Masahiro; Hanai, Jun-ichi; Akiyama, Hirotada; Abe, Masahiro; Miyazono, Kohei; Matsumoto, Toshio; Imamura, Takeshi

    2009-03-06

    Transforming growth factor-beta (TGF-beta) is crucial in numerous cellular processes, such as proliferation, differentiation, migration, and apoptosis. TGF-beta signaling is transduced by intracellular Smad proteins that are regulated by the ubiquitin-proteasome system. Smad ubiquitin regulatory factor 2 (Smurf2) prevents TGF-beta and bone morphogenetic protein signaling by interacting with Smads and inducing their ubiquitin-mediated degradation. Here we identified Pin1, a peptidylprolyl cis-trans isomerase, as a novel protein binding Smads. Pin1 interacted with Smad2 and Smad3 but not Smad4; this interaction was enhanced by the phosphorylation of (S/T)P motifs in the Smad linker region. (S/T)P motif phosphorylation also enhanced the interaction of Smad2/3 with Smurf2. Pin1 reduced Smad2/3 protein levels in a manner dependent on its peptidyl-prolyl cis-trans isomerase activity. Knockdown of Pin1 increased the protein levels of endogenous Smad2/3. In addition, Pin1 both enhanced the interaction of Smurf2 with Smads and enhanced Smad ubiquitination. Pin1 inhibited TGF-beta-induced transcription and gene expression, suggesting that Pin1 negatively regulates TGF-beta signaling by down-regulating Smad2/3 protein levels via induction of Smurf2-mediated ubiquitin-proteasomal degradation.

  14. Extracellular matrix sub-types and mechanical stretch impact human cardiac fibroblast responses to transforming growth factor beta.

    PubMed

    Watson, Chris J; Phelan, Dermot; Collier, Patrick; Horgan, Stephen; Glezeva, Nadia; Cooke, Gordon; Xu, Maojia; Ledwidge, Mark; McDonald, Kenneth; Baugh, John A

    2014-06-01

    Understanding the impact of extracellular matrix sub-types and mechanical stretch on cardiac fibroblast activity is required to help unravel the pathophysiology of myocardial fibrotic diseases. Therefore, the purpose of this study was to investigate pro-fibrotic responses of primary human cardiac fibroblast cells exposed to different extracellular matrix components, including collagen sub-types I, III, IV, VI and laminin. The impact of mechanical cyclical stretch and treatment with transforming growth factor beta 1 (TGFβ1) on collagen 1, collagen 3 and alpha smooth muscle actin mRNA expression on different matrices was assessed using quantitative real-time PCR. Our results revealed that all of the matrices studied not only affected the expression of pro-fibrotic genes in primary human cardiac fibroblast cells at rest but also affected their response to TGFβ1. In addition, differential cellular responses to mechanical cyclical stretch were observed depending on the type of matrix the cells were adhered to. These findings may give insight into the impact of selective pathological deposition of extracellular matrix proteins within different disease states and how these could impact the fibrotic environment.

  15. Transforming Growth Factor β Induces Bone Marrow Mesenchymal Stem Cell Migration via Noncanonical Signals and N-cadherin.

    PubMed

    Dubon, Maria Jose; Yu, Jinyeong; Choi, Sanghyuk; Park, Ki-Sook

    2017-02-18

    Transforming growth factor-beta (TGF-β) induces the migration and mobilization of bone marrow-derived mesenchymal stem cells (BM-MSCs) to maintain bone homeostasis during bone remodeling and facilitate the repair of peripheral tissues. Although many studies have reported the mechanisms through which TGF-β mediates the migration of various types of cells, including cancer cells, the intrinsic cellular mechanisms underlying cellular migration and mobilization of BM-MSCs mediated by TGF-β are unclear. In this study, we showed that TGF-β activated noncanonical signaling molecules, such as Akt, extracellular signal-regulated kinase 1/2 (ERK1/2), focal adhesion kinase (FAK), and p38, via TGF-β type I receptor in human BM-MSCs and murine BM-MSC-like ST2 cells. Inhibition of Rac1 by NSC23766 and Src by PP2 resulted in impaired TGF-β-mediated migration. These results suggested that the Smad-independent, noncanonical signals activated by TGF-β were necessary for migration. We also showed that N-cadherin-dependent intercellular interactions were required for TGF-β-mediated migration using functional inhibition of N-cadherin with EDTA treatment and a neutralizing antibody (GC-4 antibody) or siRNA-mediated knockdown of N-cadherin. However, N-cadherin knockdown did not affect the global activation of noncanonical signals in response to TGF-β. Therefore, these results suggested that the migration of BM-MSCs in response to TGF-β was mediated through N-cadherin and noncanonical TGF-β signals. This article is protected by copyright. All rights reserved.

  16. Orphan nuclear receptor small heterodimer partner inhibits transforming growth factor-beta signaling by repressing SMAD3 transactivation.

    PubMed

    Suh, Ji Ho; Huang, Jiansheng; Park, Yun-Yong; Seong, Hyun-A; Kim, Dongwook; Shong, Minho; Ha, Hyunjung; Lee, In-Kyu; Lee, Keesook; Wang, Li; Choi, Hueng-Sik

    2006-12-22

    Orphan nuclear receptor small heterodimer partner (SHP) is an atypical member of the nuclear receptor superfamily; SHP regulates the nuclear receptor-mediated transcription of target genes but lacks a conventional DNA binding domain. In this study, we demonstrate that SHP represses transforming growth factor-beta (TGF-beta)-induced gene expression through a direct interaction with Smad, a transducer of TGF-beta signaling. Transient transfection studies demonstrate that SHP represses Smad3-induced transcription. In vivo and in vitro protein interaction assays revealed that SHP directly interacts with Smad2 and Smad3 but not with Smad4. Mapping of domains mediating the interaction between SHP and Smad3 showed that the entire N-terminal domain (1-159 amino acids) of SHP and the linker domain of Smad3 are involved in this interaction. In vitro glutathione S-transferase pulldown competition experiments revealed the SHP-mediated repression of Smad3 transactivation through competition with its co-activator p300. SHP also inhibits the activation of endogenous TGF-beta-responsive gene promoters, the p21, Smad7, and plasminogen activator inhibitor-1 (PAI-1) promoters. Moreover, adenovirus-mediated overexpression of SHP decreases PAI-1 mRNA levels, and down-regulation of SHP by a small interfering RNA increases both the transactivation of Smad3 and the PAI-1 mRNA levels. Finally, the PAI-1 gene is expressed in SHP(-/-) mouse hepatocytes at a higher level than in normal hepatocytes. Taken together, these data indicate that SHP is a novel co-regulator of Smad3, and this study provides new insights into regulation of TGF-beta signaling.

  17. Integrin-linked kinase mediates the hydrogen peroxide-dependent transforming growth factor-β1 up-regulation.

    PubMed

    Gonzalez-Ramos, M; de Frutos, S; Griera, M; Luengo, A; Olmos, G; Rodriguez-Puyol, D; Calleros, L; Rodriguez-Puyol, M

    2013-08-01

    Transforming growth factor type-β1 (TGF-β1) has been recognized as a central mediator in many pathological events related to extracellular matrix (ECM) proteins accumulation, where their locally increased expression has been implicated in the fibrosis process of numerous organs, including glomerular fibrosis in the kidney. We and others have reported the TGF-β1 synthesis regulation by reactive oxygen species (ROS), and moreover we also described the implication of integrin-linked kinase (ILK) in the AP-1-dependent TGF-β1 up-regulation. Thus, we propose here that hydrogen peroxide (H2O2)-dependent TGF-β1 regulation may be mediated by ILK activation. First we confirmed the increase in TGF-β1 expression in human mesangial cells (HMC) after treatment with H2O2 or with an alternative H2O2-generating system such as the glucose-oxidase enzyme (GOX). By using immunoblotting, immunofluorescence, and ELISA techniques, we demonstrate that extracellular H2O2 up-regulates TGF-β1 transcription, as well as increases TGF-β1 promoter activity. Furthermore, catalase-decreased intracellular H2O2 abolished TGF-β1 up-regulation. The use of pharmacological inhibitors as well as knockdown of ILK with small interfering RNA (siRNA) demonstrated the implication of a PI3K/ILK/AKT/ERK MAPK signaling pathway axis in the H2O2-induced TGF-β1 overexpression. Finally, we explored the physiological relevance of these findings by treating HMC with angiotensin II, a known stimuli of H2O2 synthesis. Our results confirm the relevance of previous findings after a more physiological stimulus. In summary, our results provide evidence that ILK activity changes may act as a mechanism in response to different stimuli such as H2O2 in the induced TGF-β1 up-regulation in pathological or even physiological conditions.

  18. Effects of transforming growth factor-beta on long-term human cord blood monocyte cultures

    SciTech Connect

    Orcel, P.; Bielakoff, J.; De Vernejoul, M.C. )

    1990-02-01

    Transforming growth factor-beta (TGF-beta) modulates growth and differentiation in many cell types and is abundant in bone matrix. We recently showed that human cord blood monocytes cultured in the presence of 1,25(OH)2D3 acquire some features of osteoclast precursors. Since TGF-beta has been shown to influence bone resorption in organ culture, we have studied the effect of TGF-beta (1-1,000 pg/ml) on cord blood monocyte cultures. These cells were cultured on plastic substrate during 3 weeks in the presence of 20% horse serum and 10(-9) M 1,25(OH)2D3. TGF-beta, from a concentration of 10 pg/ml in the culture medium, decreased in a dose dependent manner the formation of multinucleated cells. At a concentration of TGF-beta of 1 ng/ml, the multinucleated cells were reduced to 2.1% +/- 0.3%, compared to 19.3% +/- 1.5% in control cultures. TGF-beta inhibited in a dose-dependent manner the proliferation of cord blood monocytes as assessed by 3H-thymidine incorporation at 7 and 14 days of culture. The fusion index was also decreased by 3 weeks of treatment with TGF-beta. Indomethacin did not reverse the inhibitory effects of TGF-beta. The expression of the osteoclastic phenotype was assessed using two different antibodies: 23C6, a monoclonal antibody directed against the vitronectin receptor, which is highly expressed by osteoclasts but not by adult monocytes, and an antibody to HLA-DR, which is not present on osteoclast. TGF-beta decreased the expression of HLA-DR and increased in a dose-dependent manner the proportion of 23C6-labeled cells; these results suggest that TGF-beta could modulate a differentiation effect to the osteoclastic phenotype. However, when cord blood monocytes were cultured on devitalized rat calvariae prelabeled with 45Ca, TGF-beta did not induce any 45Ca release from bone cultured with monocytes.

  19. Role of transforming growth factor beta 1 on hepatic regeneration and apoptosis in liver diseases.

    PubMed Central

    Takiya, S; Tagaya, T; Takahashi, K; Kawashima, H; Kamiya, M; Fukuzawa, Y; Kobayashi, S; Fukatsu, A; Katoh, K; Kakumu, S

    1995-01-01

    AIMS--To investigate the effects of transforming growth factor beta 1 (TGF-beta 1) on regeneration and induction of apoptosis of liver cell and bile duct in various liver diseases. METHODS--Formalin fixed paraffin wax sections of 18 liver tissue samples were obtained by needle biopsy, surgery, or necropsy; these included six liver cirrhosis, three obstructive jaundice; five fulminant hepatitis, one subacute hepatitis, and three normal liver. Expression of TGF-beta 1, apoptosis related Le(y) antigen, Fas antigen, a receptor for tumour necrosis factor, and biotin nick end labelling with terminal deoxynucleotidyl transferase mediated dUTP (TUNEL) for locating DNA fragmentation, was investigated histochemically. RESULTS--TGF-beta 1 was expressed in areas of atypical bile duct proliferation, where bile duct continuously proliferated from liver cells. In occlusive jaundice and fulminant hepatitis, TUNEL was positive in nuclei and cytoplasm of metaplastic cells which formed incomplete bile ducts, and these cells appeared to extend from TGF-beta 1 expressing liver cells. Fas antigen was found only on the cell membrane of proliferated bile duct in fulminant hepatitis, which differed from TGF-beta 1 and TUNEL positive areas. Le(y) antigen was expressed in liver cell and bile duct at the areas with atypical bile duct proliferation, but its coexpression with TUNEL was rare. CONCLUSIONS--TGF-beta 1 plays a role in the arrest of liver cell regeneration and atypical bile duct proliferation, and in areas of rapidly progressing atypical bile duct proliferation, such as in fulminant hepatitis or bile retention. Apoptosis appears to be induced by TGF-beta 1. This phenomenon may account for the inadequate hepatic regeneration that occurs with liver disease. Images PMID:8567993

  20. Transforming growth factor-ß1 genotype and susceptibility to chronic obstructive pulmonary disease

    PubMed Central

    Wu, L; Chau, J; Young, R; Pokorny, V; Mills, G; Hopkins, R; McLean, L; Black, P

    2004-01-01

    Background: Only a few long term smokers develop symptomatic chronic obstructive pulmonary disease (COPD) and this may be due, at least in part, to genetic susceptibility to the disease. Transforming growth factor ß1 (TGF-ß1) has a number of actions that make it a candidate for a role in the pathogenesis of COPD. We have investigated a single nucleotide polymorphism at exon 1 nucleotide position 29 (T→C) of the TGF-ß1 gene that produces a substitution at codon 10 (Leu→Pro). Methods: The frequency of this polymorphism was determined in 165 subjects with COPD, 140 healthy blood donors, and 76 smokers with normal lung function (resistant smokers) using the polymerase chain reaction and restriction enzyme fragment length polymorphism. Results: The distribution of genotypes was Leu-Leu (41.8%), Leu-Pro (50.3%), and Pro-Pro (7.9%) for subjects with COPD, which was significantly different from the control subjects (blood donors: Leu-Leu (29.3%), Leu-Pro (52.1%) and Pro-Pro (18.6%), p = 0.006; resistant smokers: Leu-Leu (28.9%), Leu-Pro (51.3%) and Pro-Pro (19.7%), p = 0.02). The Pro10 allele was less common in subjects with COPD (33%) than in blood donors (45%; OR = 0.62, 95% CI 0.45 to 0.86, p = 0.005) and resistant smokers (45%; OR = 0.59, 95% CI 0.40 to 0.88, p = 0.01). Conclusions: The proline allele at codon 10 of the TGF-ß1 gene occurs more commonly in control subjects than in individuals with COPD. This allele is associated with increased production of TGF-ß1 which raises the possibility that TGF-ß1 has a protective role in COPD. PMID:14760152

  1. Genetic variation in Transforming Growth Factor beta 1 and mammographic density in Singapore Chinese women

    PubMed Central

    Lee, Eunjung; Van den Berg, David; Hsu, Chris; Ursin, Giske; Koh, Woon-Puay; Yuan, Jian-Min; Stram, Daniel O.; Yu, Mimi C.; Wu, Anna H.

    2013-01-01

    Transforming growth factor-beta (TGF-β) plays a critical role in normal mammary development and morphogenesis. Decreased TGF-β signaling has been associated with increased mammographic density. Percent mammographic density (PMD) adjusted for age and body mass index (BMI) is a strong risk factor and predictor of breast cancer risk. PMD is highly heritable, but few genetic determinants have been identified. We investigated the association between genetic variation in TGFB1 and PMD using a cross-sectional study of 2,038 women who were members of the population-based Singapore Chinese Health Study cohort. We assessed PMD using a computer-assisted method. We used linear regression to examine the association between 9 tagging SNPs of TGFB1 and PMD and their interaction with parity, adjusting for age, BMI, and dialect group. We calculated ‘P-values adjusted for correlated tests’ (PACT) to account for multiple testing. The strongest association was observed for rs2241716. Adjusted PMD was higher by 1.5% per minor allele (PACT =0.04). When stratifying by parity, this association was limited to nulliparous women. For nulliparous women, adjusted PMD was higher by 8.6% per minor allele (PACT=0.003; P for interaction with parity=0.002). Three additional TGFB1 tagging SNPs, which were in linkage disequilibrium with rs2241716, were statistically significantly associated with adjusted PMD (PACT<0.05) for nulliparous women. However, none of these three SNPs showed statistically significant association after adjusting for rs2241716. Our data support that TGFB1 genetic variation may be an important genetic determinant of mammographic density measure that predicts breast cancer risk, particularly in nulliparous women. PMID:23333936

  2. Transforming growth factor-beta receptor-3 is associated with pulmonary emphysema.

    PubMed

    Hersh, Craig P; Hansel, Nadia N; Barnes, Kathleen C; Lomas, David A; Pillai, Sreekumar G; Coxson, Harvey O; Mathias, Rasika A; Rafaels, Nicholas M; Wise, Robert A; Connett, John E; Klanderman, Barbara J; Jacobson, Francine L; Gill, Ritu; Litonjua, Augusto A; Sparrow, David; Reilly, John J; Silverman, Edwin K

    2009-09-01

    Chronic obstructive pulmonary disease (COPD) is a heterogeneous syndrome, including emphysema and airway disease. Phenotypes defined on the basis of chest computed tomography (CT) may decrease disease heterogeneity and aid in the identification of candidate genes for COPD subtypes. To identify these genes, we performed genome-wide linkage analysis in extended pedigrees from the Boston Early-Onset COPD Study, stratified by emphysema status (defined by chest CT scans) of the probands, followed by genetic association analysis of positional candidate genes. A region on chromosome 1p showed strong evidence of linkage to lung function traits in families of emphysema-predominant probands in the stratified analysis (LOD score = 2.99 in families of emphysema-predominant probands versus 1.98 in all families). Association analysis in 949 individuals from 127 early-onset COPD pedigrees revealed association for COPD-related traits with an intronic single-nucleotide polymorphism (SNP) in transforming growth factor-beta receptor-3 (TGFBR3) (P = 0.005). This SNP was significantly associated with COPD affection status comparing 389 cases from the National Emphysema Treatment Trial to 472 control smokers (P = 0.04), and with FEV(1) (P = 0.004) and CT emphysema (P = 0.05) in 3,117 subjects from the International COPD Genetics Network. Gene-level replication of association with lung function was seen in 427 patients with COPD from the Lung Health Study. In conclusion, stratified linkage analysis followed by association testing identified TGFBR3 (betaglycan) as a potential susceptibility gene for COPD. Published human microarray and murine linkage studies have also demonstrated the importance of TGFBR3 in emphysema and lung function, and our group and others have previously found association of COPD-related traits with TGFB1, a ligand for TGFBR3.

  3. Characterization of the rat transforming growth factor alpha gene and identification of promoter sequences.

    PubMed Central

    Blasband, A J; Rogers, K T; Chen, X R; Azizkhan, J C; Lee, D C

    1990-01-01

    We have determined the complete nucleotide sequence of rat transforming growth factor alpha (TGF alpha) mRNA and characterized the six exons that encode this transcript. These six exons span approximately 85 kilobases of genomic DNA, with exons 1 to 3 separated by particularly large introns. What had previously been thought to represent a species-specific difference in the size of the TGF alpha precursor (proTGF alpha) is now shown to be due to microheterogeneity in the splicing of exons 2 and 3. This results from a tandem duplication of the acceptor CAG and gives rise to two alternate forms (159 and 160 amino acids) of the integral membrane precursor. Exon 6, which encodes the 3' untranslated region of TGF alpha mRNA, also encodes, on the opposite strand, a small (approximately 200-nucleotide) transcript whose sequence predicts an open reading frame of 51 amino acids. Expression of this latter transcript does not appear to be coregulated with that of TGF alpha mRNA. Primer extension and S1 nuclease analyses of authentic TGF alpha transcripts revealed two major and multiple minor 5' ends which span more than 200 base pairs of DNA in a G + C-rich region that lacks canonical CCAAT or TATA sequences. The 5' ends of six independently derived cDNAs localized to five different sites in this same region. Restriction fragments that overlap these transcription start sites and extend approximately 300 base pairs in the 5' direction faithfully promote transcription in vitro with HeLa cell nuclear extracts. In addition, they direct the expression of the bacterial chloramphenicol acetyltransferase gene in transient-transfection assays. Images PMID:2325647

  4. Urinary transforming growth factor beta1 in children and adolescents with congenital solitary kidney.

    PubMed

    Wasilewska, Anna; Zoch-Zwierz, Walentyna; Taranta-Janusz, Katarzyna

    2009-04-01

    The aim of the study was to assess urinary transforming growth factor beta1 (TGF beta1) level in children and adolescents with congenital solitary kidney (CSK), depending on estimated glomerular filtration rate (eGFR) and compensatory overgrowth of the kidney. The study group (I) consisted of 65 children and young adults, 0.5-22 years of age (median 10.0 years) with CSK and no other urinary defects. The control group (C) contained 44 healthy children and adolescents, 0.25-21 years old (median 10.3 years). We used an enzyme-linked immunosorbent assay (ELISA) to determine the urinary level of TGF beta1, the Jaffe method to assess creatinine concentration, and the Schwartz formula to estimate GFR. Kidney length was measured while the patient was in a supine position, and overgrowth (O%) was calculated with reference to the charts. Urinary TGF beta1 level in CSK patients was more than twice as high as that in controls (P < 0.05). Also, eGFR in patients with CSK exceeded the values in the control group (P < 0.01). Compensatory overgrowth of the solitary kidney was found (median 19.44%). Urinary TGF beta1 concentration was positively correlated with eGFR (r = 0.247, P < 0.05), uric acid concentration (r = 0.333, P < 0.01), and percentage of overgrowth (r = 0.338, P < 0.01) and body mass index (BMI) centile (r = 0.274, P < 0.05). We concluded that, although proteinuria and progressive renal insufficiency is not observed in patients with CSK during childhood, the renal haemodynamic changes are present and may be a risk factor for impairment of renal function and hypertension in future life.

  5. Hydrogen Sulfide Inhibits Transforming Growth Factor-β1-Induced EMT via Wnt/Catenin Pathway.

    PubMed

    Guo, Lin; Peng, Wen; Tao, Jie; Lan, Zhen; Hei, Hongya; Tian, Lulu; Pan, Wanma; Wang, Li; Zhang, Xuemei

    2016-01-01

    Hydrogen sulfide (H2S) has anti-fibrotic potential in lung, kidney and other organs. The exogenous H2S is released from sodium hydrosulfide (NaHS) and can influence the renal fibrosis by blocking the differentiation of quiescent renal fibroblasts to myofibroblasts. But whether H2S affects renal epithelial-to-mesenchymal transition (EMT) and the underlying mechanisms remain unknown. Our study is aimed at investigating the in vitro effects of H2S on transforming growth factor-β1 (TGF-β1)-induced EMT in renal tubular epithelial cells (HK-2 cells) and the associated mechanisms. The induced EMT is assessed by Western blotting analysis on the expressions of α-SMA, E-cadherin and fibronectin. HK-2 cells were treated with NaHS before incubating with TGF-β1 to investigate its effect on EMT and the related molecular mechanism. Results demonstrated that NaHS decreased the expression of α-SMA and fibronectin, and increased the expression of E-cadherin. NaHS reduced the expression of TGF-β receptor type I (TβR I) and TGF-β receptor type II (TβR II). In addition, NaHS attenuated TGF-β1-induced increase of β-catenin expression and ERK phosphorylation. Moreover, it inhibited the TGF-β1-induced nuclear translocation of ββ-catenin. These effects of NaHS on fibronectin, E-cadherin and TβR I were abolished by the ERK inhibitor U0126 or β-catenin inhibitor XAV939, or β-catenin siRNA interference. We get the conclusion that NaHS attenuated TGF-β1-induced EMT in HK-2 cells through both ERK-dependent and β-catenin-dependent pathways.

  6. Transforming growth factor-β in normal nociceptive processing and pathological pain models.

    PubMed

    Lantero, Aquilino; Tramullas, Mónica; Díaz, Alvaro; Hurlé, María A

    2012-02-01

    The transforming growth factor-β (TGF-β) superfamily is a multifunctional, contextually acting family of cytokines that participate in the regulation of development, disease and tissue repair in the nervous system. The TGF-β family is composed of several members, including TGF-βs, bone morphogenetic proteins (BMPs) and activins. In this review, we discuss recent findings that suggest TGF-β function as important pleiotropic modulators of nociceptive processing both physiologically and under pathological painful conditions. The strategy of increasing TGF-β signaling by deleting "BMP and activin membrane-bound inhibitor" (BAMBI), a TGF-β pseudoreceptor, has demonstrated the inhibitory role of TGF-β signaling pathways in normal nociception and in inflammatory and neuropathic pain models. In particular, strong evidence suggests that TGF-β1 is a relevant mediator of nociception and has protective effects against the development of chronic neuropathic pain by inhibiting the neuroimmune responses of neurons and glia and promoting the expression of endogenous opioids within the spinal cord. In the peripheral nervous system, activins and BMPs function as target-derived differentiation factors that determine and maintain the phenotypic identity and circuit assembly of peptidergic nociceptors. In this context, activin is involved in the complex events of neuroinflammation that modulate the expression of pain during wound healing. These findings have provided new insights into the physiopathology of nociception. Moreover, specific members of the TGF-β family and their signaling effectors and modulator molecules may be promising molecular targets for novel therapeutic agents for pain management.

  7. Orofacial clefts, parental cigarette smoking, and transforming growth factor-alpha gene variants

    SciTech Connect

    Shaw, G.M.; Wasserman, C.R.; O`Malley, C.D.

    1996-03-01

    Results of studies determine whether women who smoke during early pregnancy are at increased risk of delivering infants with orofacial clefts have been mixed, and recently a gene-environment interaction between maternal smoking, transforming growth factor-alpha (TGFa), and clefting has been reported. Using a large population-based case-control study, we investigated whether parental periconceptional cigarette smoking was associated with an increased risk for having offspring with orofacial clefts. We also investigated the influence of genetic variation of the TGFa locus on the relation between smoking and clefting. Parental smoking information was obtained from telephone interviews with mothers of 731 (84.7% of eligible) orofacial cleft case infants and with mothers of 734 (78.2%) nonmalformed control infants. DNA was obtained from newborn screening blood spots and genotyped for the allelic variants of TGFa. We found that risks associated with maternal smoking were most elevated for isolated cleft lip with or without cleft palate, (odds ratio 2.1 [95% confidence interval 1.3-3.6]) and for isolated cleft palate (odds ratio 2.2 [1.1-4.5]) when mothers smoked {ge} 20 cigarrettes/d. These risks for white infants ranged from 3-fold to 11-fold across phenotypic groups. Paternal smoking was not associated with clefting among the offspring of nonsmoking mothers, and passive smoke exposures were associated with at most slightly increased risks. This study offers evidence that the risk for orofacial clefting in infants may be influenced by maternal smoke exposures alone as well as in combination (gene-environment interaction) with the presence of the uncommon TGFa allele. 56 refs., 5 tabs.

  8. Transforming growth factor beta (TGF-β) and inflammation in cancer

    PubMed Central

    Bierie, Brian; Moses, Harold L.

    2009-01-01

    The transforming growth factor beta (TGF-β) has been studied with regard to the regulation of cell behavior for over three decades. A large body of research has been devoted to the regulation of epithelial cell and derivative carcinoma cell populations in vitro and in vivo. TGF-β has been shown to inhibit epithelial cell cycle progression and promote apoptosis that together significantly contribute to the tumor suppressive role for TGF-β during carcinoma initiation and progression. However, TGF-β is also able to promote an epithelial to mesenchymal transition that has been associated with increased tumor cell motility, invasion and metastasis. However, it has now been shown that loss of carcinoma cell responsiveness to TGF-β stimulation can also promote metastasis. Interestingly, the enhanced metastasis in the absence of a carcinoma cell response to TGF-β stimulation has been shown to involve increased chemokine production resulting in recruitment of pro-metastatic myeloid derived suppressor cell (MDSC) populations to the tumor microenvironment at the leading invasive edge. When present, MDSCs enhance angiogenesis, promote immune tolerance and provide matrix degrading enzymes that promote tumor progression and metastasis. Further, the recruitment of MDSC populations in this context likely enhances the classic role for TGF-β in immune suppression since the MDSCs are an abundant source of TGF-β production. Importantly, it is now clear that carcinoma-immune cell cross-talk initiated by TGF-β signaling within the carcinoma cell is a significant determinant worth consideration when designing therapeutic strategies to manage tumor progression and metastasis. PMID:20018551

  9. The role of transforming growth factor alpha in rat craniofacial development and chondrogenesis.

    PubMed

    Huang, L; Solursh, M; Sandra, A

    1996-08-01

    To explore the possible role of transforming growth factor alpha (TGF-alpha) in craniofacial development, its expression in the craniofacial region of rat embryos from embryonic day (d) 9 to d 20 was examined by in situ hybridisation and immunostaining. The TGF-alpha transcripts were first detected in the neural fold of embryonic d 9 and 10 embryos. In the craniofacial region, the TGF-alpha transcripts were not detected until embryonic d 16 in mesenchyme surrounding the olfactory bulb, within the olfactory bulb, the nasal capsule, vomeronasal organ, and vibrissal follicle. In addition, TGF-alpha message was detected in mesenchyme in the vicinity of Meckel's cartilage, and in the dental epithelium and lamina. This expression pattern of TGF-alpha transcripts persisted until embryonic d 17 but disappeared by d 18. The presence of TGF-alpha protein largely coincided with TGF-alpha message although, unlike the message, it persisted throughout later embryogenesis in the craniofacial region. The possible function of TGF-alpha in chondrogenesis was explored by employing the micromass culture technique. Cartilage nodule formation in mesenchymal cells cultured from rat mandibles in the presence of TGF-alpha was significantly inhibited. This inhibitory effect of TGF-alpha on chondrogenesis was reversed by addition of antibody against the EGF receptor, which crossreacts with the TGF-alpha receptor. The inhibitory effect of TGF-alpha on chondrogenesis in vitro was further confirmed by micromass culture using mesenchymal cells from rat embryonic limb bud. Taken together, these results demonstrate the involvement of TGF-alpha in chondrogenesis during embryonic development, possibly by way of a specific inhibition of cartilage formation from mesenchymal precursor cells.

  10. The role of transforming growth factor alpha in rat craniofacial development and chondrogenesis.

    PubMed Central

    Huang, L; Solursh, M; Sandra, A

    1996-01-01

    To explore the possible role of transforming growth factor alpha (TGF-alpha) in craniofacial development, its expression in the craniofacial region of rat embryos from embryonic day (d) 9 to d 20 was examined by in situ hybridisation and immunostaining. The TGF-alpha transcripts were first detected in the neural fold of embryonic d 9 and 10 embryos. In the craniofacial region, the TGF-alpha transcripts were not detected until embryonic d 16 in mesenchyme surrounding the olfactory bulb, within the olfactory bulb, the nasal capsule, vomeronasal organ, and vibrissal follicle. In addition, TGF-alpha message was detected in mesenchyme in the vicinity of Meckel's cartilage, and in the dental epithelium and lamina. This expression pattern of TGF-alpha transcripts persisted until embryonic d 17 but disappeared by d 18. The presence of TGF-alpha protein largely coincided with TGF-alpha message although, unlike the message, it persisted throughout later embryogenesis in the craniofacial region. The possible function of TGF-alpha in chondrogenesis was explored by employing the micromass culture technique. Cartilage nodule formation in mesenchymal cells cultured from rat mandibles in the presence of TGF-alpha was significantly inhibited. This inhibitory effect of TGF-alpha on chondrogenesis was reversed by addition of antibody against the EGF receptor, which crossreacts with the TGF-alpha receptor. The inhibitory effect of TGF-alpha on chondrogenesis in vitro was further confirmed by micromass culture using mesenchymal cells from rat embryonic limb bud. Taken together, these results demonstrate the involvement of TGF-alpha in chondrogenesis during embryonic development, possibly by way of a specific inhibition of cartilage formation from mesenchymal precursor cells. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 9 PMID:8771398

  11. Transforming Growth Factor β1 (TGF-β1) in the Sera of Postmenopausal Osteoporotic Females

    PubMed Central

    Faraji, Aazam; Abtahi, Shabnam; Ghaderi, Abbas; Samsami Dehaghani, Alamtaj

    2016-01-01

    Background Postmenopausal osteoporosis is a major cause of morbidity in postmenopausal females. Transforming growth factor β1 (TGF-β1) and interleukin 18 (IL-18) play complex roles in normal bone metabolism, and in pathophysiology of postmenopausal osteoporosis. Objectives The aim of this study was to design an analytic cross sectional study in order to further clarify the role of TGF-β1 and IL-18 in osteoporosis of postmenopausal females. Methods A cross sectional study including 65 postmenopausal osteoporotic females as cases and 69 postmenopausal females of similar age without osteoporosis as controls was conducted. Dual energy X-ray absorptiometry (DXA) was used to determine bone mass density (BMD) of participants and T-scoring was applied to establish whether the patient has osteoporosis or not. Serum TGF-β1 and IL-18 levels were measured by quantitative sandwich Enzyme linked immunosorbent assay (ELISA). Results Serum TGF-β1 levels were significantly higher in osteoporotic postmenopausal females than non-osteoporotic individuals (23.8 vs. 15.8 ng/mL; P = 0.009). There was no difference between IL-18 levels in the sera of osteoporotic and non-osteoporotic postmenopausal females in this study. There was a positive correlation between body mass index (BMI) and serum level of TGF-β1 (P = 0.04). Conclusions Our study demonstrated that TGF-β1 serum levels is higher in osteoporotic postmenopausal females than non-osteoporotic ones, and probably aberrant increase in TGF-β1 in postmenopausal females can result in uncoupled bone resorption and formation, which leads to osteoporosis. PMID:28123435

  12. Anti-transforming growth factor-beta monoclonal antibodies prevent lung injury in hemorrhaged mice.

    PubMed

    Shenkar, R; Coulson, W F; Abraham, E

    1994-09-01

    Acute lung injury, characterized as the adult respiratory distress syndrome (ARDS), is a common clinical occurrence following blood loss and injury. We previously found increased levels of transforming growth factor (TGF)-beta 1 mRNA in murine intraparenchymal mononuclear cells and in alveolar macrophages within 1 h after hemorrhage. Because TGF-beta has potent proinflammatory and immunoregulatory properties, we investigated the effect of blocking TGF-beta with mAb on hemorrhage-induced pathology, cytokine mRNA levels in lungs, as well as survival from pneumonia. Mice treated with anti-TGF-beta mAb showed normal pulmonary histology 3 days after hemorrhage and resuscitation in contrast to the mononuclear and neutrophil infiltrates, intraalveolar hemorrhage, and interstitial edema found in hemorrhaged mice either treated with control antibody or not treated with any antibody. Decreased mRNA levels for IL-1 beta, TNF-alpha, IL-6, IL-10, and IFN-gamma as compared with untreated, hemorrhaged controls were present in intraparenchymal pulmonary mononuclear cells following therapy with anti-TGF-beta. In contrast, therapy with anti-TGF-beta increased mRNA levels for IL-1 beta and TNF-alpha in alveolar macrophages and for TGF-beta in peripheral blood mononuclear cells collected 3 days after hemorrhage. Administration of anti-TGF-beta to hemorrhaged mice did not correct the enhanced susceptibility to Pseudomonas aeruginosa pneumonia that exists after hemorrhage. These results suggest that TGF-beta has an important role in hemorrhage-induced acute lung injury, but does not contribute to the post-hemorrhage depression in pulmonary antibacterial response.

  13. Analysis of small latent transforming growth factor-beta complex formation and dissociation by surface plasmon resonance. Absence of direct interaction with thrombospondins.

    PubMed

    Bailly, S; Brand, C; Chambaz, E M; Feige, J J

    1997-06-27

    Transforming