Sample records for additional growth factors

  1. Media composition: growth factors.

    PubMed

    Hegde, Aparna; Behr, Barry

    2012-01-01

    Despite the fact that the fundamental principle underlying the most common method of culture media constitution is that of mimicking the natural environment of the preimplantation embryo, one major difference that remains between current embryo culture media and in vivo conditions is the absence of growth factors in vitro. Numerous growth factors are known to be present in the in vivo environment of human and nonhuman preimplantation embryos, often with peak concentrations corresponding to when fertilization and preimplantation embryo growth would occur. Although these growth factors are found in very small concentrations, they have a profound effect on tissue growth and differentiation through attachment to factor-specific receptors on cell surfaces. Receptors for many different growth factors have also been detected in human preimplantation embryos. Preimplantation embryos themselves express many growth factors. The growth factors and receptors are metabolically costly to produce, and thus their presence in the environment of the preimplantation embryo and in the embryo respectively strongly implies that embryos are designed to encounter and respond to the corresponding factors. Studies of embryo coculture also indirectly suggest that growth factors can improve in vitro development. Several animal and human studies attest to a probable beneficial effect of addition of growth factors to culture media. However, there is still ambiguity regarding the exact role of growth factors in embryonic development, the optimal dose of growth factors to be added to culture media, the combinatorial effect and endocrine of growth factors in embryonic development.

  2. Fibroblast growth factor receptors in breast cancer.

    PubMed

    Wang, Shuwei; Ding, Zhongyang

    2017-05-01

    Fibroblast growth factor receptors are growth factor receptor tyrosine kinases, exerting their roles in embryogenesis, tissue homeostasis, and development of breast cancer. Recent genetic studies have identified some subtypes of fibroblast growth factor receptors as strong genetic loci associated with breast cancer. In this article, we review the recent epidemiological findings and experiment results of fibroblast growth factor receptors in breast cancer. First, we summarized the structure and physiological function of fibroblast growth factor receptors in humans. Then, we discussed the common genetic variations in fibroblast growth factor receptors that affect breast cancer risk. In addition, we also introduced the potential roles of each fibroblast growth factor receptors isoform in breast cancer. Finally, we explored the potential therapeutics targeting fibroblast growth factor receptors for breast cancer. Based on the biological mechanisms of fibroblast growth factor receptors leading to the pathogenesis in breast cancer, targeting fibroblast growth factor receptors may provide new opportunities for breast cancer therapeutic strategies.

  3. Insulin-like growth factor I (IGF-1) Ec/Mechano Growth factor--a splice variant of IGF-1 within the growth plate.

    PubMed

    Schlegel, Werner; Raimann, Adalbert; Halbauer, Daniel; Scharmer, Daniela; Sagmeister, Susanne; Wessner, Barbara; Helmreich, Magdalena; Haeusler, Gabriele; Egerbacher, Monika

    2013-01-01

    Human insulin-like growth factor 1 Ec (IGF-1Ec), also called mechano growth factor (MGF), is a splice variant of insulin-like growth factor 1 (IGF-1), which has been shown in vitro as well as in vivo to induce growth and hypertrophy in mechanically stimulated or damaged muscle. Growth, hypertrophy and responses to mechanical stimulation are important reactions of cartilaginous tissues, especially those in growth plates. Therefore, we wanted to ascertain if MGF is expressed in growth plate cartilage and if it influences proliferation of chondrocytes, as it does in musculoskeletal tissues. MGF expression was analyzed in growth plate and control tissue samples from piglets aged 3 to 6 weeks. Furthermore, growth plate chondrocyte cell culture was used to evaluate the effects of the MGF peptide on proliferation. We showed that MGF is expressed in considerable amounts in the tissues evaluated. We found the MGF peptide to be primarily located in the cytoplasm, and in some instances, it was also found in the nucleus of the cells. Addition of MGF peptides was not associated with growth plate chondrocyte proliferation.

  4. Transforming growth factor alpha, Shope fibroma growth factor, and vaccinia growth factor can replace myxoma growth factor in the induction of myxomatosis in rabbits.

    PubMed

    Opgenorth, A; Nation, N; Graham, K; McFadden, G

    1993-02-01

    The epidermal growth factor (EGF) homologues encoded by vaccinia virus, myxoma virus, and malignant rabbit fibroma virus have been shown to contribute to the pathogenicity of virus infection upon inoculation of susceptible hosts. However, since the primary structures of these growth factors and the disease profiles induced by different poxvirus genera vary substantially, the degree to which the various EGF homologues perform similar roles in viral pathogenesis remains unclear. In order to determine whether different EGF-like growth factors can perform qualitatively similar functions in the induction of myxomatosis in rabbits, we created recombinant myxoma virus variants in which the native growth factor, myxoma growth factor (MGF), was disrupted and replaced with either vaccinia virus growth factor, Shope fibroma growth factor, or rat transforming growth factor alpha. Unlike the control virus containing an inactivated MGF gene, which caused marked attenuation of the disease syndrome and substantially less proliferation of the epithelial cell layers in the conjunctiva and respiratory tract, the recombinant myxoma virus strains expressing heterologous growth factors produced infections which were both clinically and histopathologically indistinguishable from wild-type myxomatosis. We conclude that these poxviral and cellular EGF-like growth factors, which are diverse with respect to primary structure and origin, have similar biological functions in the context of myxoma virus pathogenesis and are mitogenic for the same target cells.

  5. Insulin-Like Growth Factor I (IGF-1) Ec/Mechano Growth Factor – A Splice Variant of IGF-1 within the Growth Plate

    PubMed Central

    Schlegel, Werner; Raimann, Adalbert; Halbauer, Daniel; Scharmer, Daniela; Sagmeister, Susanne; Wessner, Barbara; Helmreich, Magdalena; Haeusler, Gabriele; Egerbacher, Monika

    2013-01-01

    Human insulin-like growth factor 1 Ec (IGF-1Ec), also called mechano growth factor (MGF), is a splice variant of insulin-like growth factor 1 (IGF-1), which has been shown in vitro as well as in vivo to induce growth and hypertrophy in mechanically stimulated or damaged muscle. Growth, hypertrophy and responses to mechanical stimulation are important reactions of cartilaginous tissues, especially those in growth plates. Therefore, we wanted to ascertain if MGF is expressed in growth plate cartilage and if it influences proliferation of chondrocytes, as it does in musculoskeletal tissues. MGF expression was analyzed in growth plate and control tissue samples from piglets aged 3 to 6 weeks. Furthermore, growth plate chondrocyte cell culture was used to evaluate the effects of the MGF peptide on proliferation. We showed that MGF is expressed in considerable amounts in the tissues evaluated. We found the MGF peptide to be primarily located in the cytoplasm, and in some instances, it was also found in the nucleus of the cells. Addition of MGF peptides was not associated with growth plate chondrocyte proliferation. PMID:24146828

  6. Ocular Angiogenesis: Vascular Endothelial Growth Factor and Other Factors.

    PubMed

    Rubio, Roman G; Adamis, Anthony P

    2016-01-01

    Systematic study of the mechanisms underlying pathological ocular neovascularization has yielded a wealth of knowledge about pro- and anti-angiogenic factors that modulate diseases such as neovascular age-related macular degeneration. The evidence implicating vascular endothelial growth factor (VEGF) in particular has led to the development of a number of approved anti-VEGF therapies. Additional proangiogenic targets that have emerged as potential mediators of ocular neovascularization include hypoxia-inducible factor-1, angiopoietin-2, platelet-derived growth factor-B and components of the alternative complement pathway. As for VEGF, knowledge of these factors has led to a product pipeline of many more novel agents that are in various stages of clinical development in the setting of ocular neovascularization. These agents are represented by a range of drug classes and, in addition to novel small- and large-molecule VEGF inhibitors, include gene therapies, small interfering RNA agents and tyrosine kinase inhibitors. In addition, combination therapy is beginning to emerge as a strategy to improve the efficacy of individual therapies. Thus, a variety of agents, whether administered alone or as adjunctive therapy with agents targeting VEGF, offer the promise of expanding the range of treatments for ocular neovascular diseases. © 2016 S. Karger AG, Basel.

  7. Release kinetics of platelet-derived and plasma-derived growth factors from autologous plasma rich in growth factors.

    PubMed

    Anitua, Eduardo; Zalduendo, Mari Mar; Alkhraisat, Mohammad Hamdan; Orive, Gorka

    2013-10-01

    Many studies have evaluated the biological effects of platelet rich plasma reporting the final outcomes on cell and tissues. However, few studies have dealt with the kinetics of growth factor delivery by plasma rich in growth factors. Venous blood was obtained from three healthy volunteers and processed with PRGF-Endoret technology to prepare autologous plasma rich in growth factors. The gel-like fibrin scaffolds were then incubated in triplicate, in a cell culture medium to monitor the release of PDGF-AB, VEGF, HGF and IGF-I during 8 days of incubation. A leukocyte-platelet rich plasma was prepared employing the same technology and the concentrations of growth factors and interleukin-1β were determined after 24h of incubation. After each period, the medium was collected, fibrin clot was destroyed and the supernatants were stored at -80°C until analysis. The growth factor delivery is diffusion controlled with a rapid initial release by 30% of the bioactive content after 1h of incubation and a steady state release when almost 70% of the growth factor content has been delivered. Autologous fibrin matrix retained almost 30% of the amount of the growth factors after 8 days of incubation. The addition of leukocytes to the formula of platelet rich plasma did not increase the concentration of the growth factors, while it drastically increased the presence of pro-inflammatory IL-1β. Further studies employing an in vitro inflammatory model would be interesting to study the difference in growth factors and pro-inflammatory cytokines between leukocyte-free and leukocyte-rich platelet rich plasma. Copyright © 2013 Elsevier GmbH. All rights reserved.

  8. Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion

    PubMed Central

    Gorin, Caroline; Rochefort, Gael Y.; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Germain, Stéphane

    2016-01-01

    Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. Significance The results from the present study show that fibroblast growth factor-2 (FGF-2) priming is more

  9. Delivery of growth factors for tissue regeneration and wound healing.

    PubMed

    Koria, Piyush

    2012-06-01

    Growth factors are soluble secreted proteins capable of affecting a variety of cellular processes important for tissue regeneration. Consequently, the self-healing capacity of patients can be augmented by artificially enhancing one or more processes important for healing through the application of growth factors. However, their application in clinics remains limited due to lack of robust delivery systems and biomaterial carriers. Interestingly, all clinically approved therapies involving growth factors utilize some sort of a biomaterial carrier for growth factor delivery. This suggests that biomaterial delivery systems are extremely important for successful usage of growth factors in regenerative medicine. This review outlines the role of growth factors in tissue regeneration, and their application in both pre-clinical animal models of regeneration and clinical trials is discussed. Additionally, current status of biomaterial substrates and sophisticated delivery systems such as nanoparticles for delivery of exogenous growth factors and peptides in humans are reviewed. Finally, issues and possible future research directions for growth factor therapy in regenerative medicine are discussed.

  10. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.

    PubMed

    Gaviglio, Angela L; Knelson, Erik H; Blobe, Gerard C

    2017-05-01

    High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. © FASEB.

  11. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation

    PubMed Central

    Gaviglio, Angela L.; Knelson, Erik H.; Blobe, Gerard C.

    2017-01-01

    High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor–like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.—Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. PMID:28174207

  12. Growth factor effects on costal chondrocytes for tissue engineering fibrocartilage

    PubMed Central

    Johns, D.E.; Athanasiou, K.A.

    2010-01-01

    Tissue engineered fibrocartilage could become a feasible option for replacing tissues like the knee meniscus or temporomandibular joint disc. This study employed five growth factors insulin-like growth factor-I, transforming growth factor-β1, epidermal growth factor, platelet-derived growth factor-BB, and basic fibroblast growth factor in a scaffoldless approach with costal chondrocytes, attempting to improve biochemical and mechanical properties of engineered constructs. Samples were quantitatively assessed for total collagen, glycosaminoglycans, collagen type I, collagen type II, cells, compressive properties, and tensile properties at two time points. Most treated constructs were worse than the no growth factor control, suggesting a detrimental effect, but the IGF treatment tended to improve the constructs. Additionally, the 6wk time point was consistently better than 3wks, with total collagen, glycosaminoglycans, and aggregate modulus doubling during this time. Further optimization of the time in culture and exogenous stimuli will be important in making a more functional replacement tissue. PMID:18597118

  13. Insulin-like growth factor and fibroblast growth factor expression profiles in growth-restricted fetal sheep pancreas.

    PubMed

    Chen, Xiaochuan; Rozance, Paul J; Hay, William W; Limesand, Sean W

    2012-05-01

    Placental insufficiency results in intrauterine growth restriction (IUGR), impaired fetal insulin secretion and less fetal pancreatic β-cell mass, partly due to lower β-cell proliferation rates. Insulin-like growth factors (IGFs) and fibroblast growth factors (FGFs) regulate fetal β-cell proliferation and pancreas development, along with transcription factors, such as pancreatic and duodenal homeobox 1 (PDX-1). We determined expression levels for these growth factors, their receptors and IGF binding proteins in ovine fetal pancreas and isolated islets. In the IUGR pancreas, relative mRNA expression levels of IGF-I, PDX-1, FGF7 and FGFR2IIIb were 64% (P < 0.01), 76% (P < 0.05), 76% (P < 0.05) and 52% (P < 0.01) lower, respectively, compared with control fetuses. Conversely, insulin-like growth factor binding protein 2 (IGFBP-2) mRNA and protein concentrations were 2.25- and 1.2-fold greater (P < 0.05) in the IUGR pancreas compared with controls. In isolated islets from IUGR fetuses, IGF-II and IGFBP-2 mRNA concentrations were 1.5- and 3.7-fold greater (P < 0.05), and insulin mRNA was 56% less (P < 0.05) than control islets. The growth factor expression profiles for IGF and FGF signaling pathways indicate that declines in β-cell mass are due to decreased growth factor signals for both pancreatic progenitor epithelial cell and mature β-cell replication.

  14. Growth factor withdrawal in combination with sodium butyrate addition extends culture longevity and enhances antibody production in CHO cells.

    PubMed

    Hong, Jong Kwang; Lee, Gyun Min; Yoon, Sung Kwan

    2011-09-10

    The effect of growth factor (GF) and sodium butyrate (NaBu) on Chinese hamster ovary (CHO) cell growth, cell viability and antibody production was investigated using shaking flasks in GF-containing and GF-deficient medium containing 0, 1 and 3mM NaBu. The withdrawal of GF and the addition of NaBu suppressed cell growth, but they significantly increased specific antibody productivity, q(Ab). Interestingly, the withdrawal of GF in combination with the addition of NaBu markedly retarded cell death, leading to extended culture longevity. For instance, at 3mM NaBu, cell viability fell below 80% after day 4 in GF-containing medium, but it remained over 80% until day 18 in GF-deficient medium. Due to the enhanced q(Ab) and the extended culture longevity, approximately 2-fold increase in total antibody production was achieved in pseudo-perfusion culture with 1mM NaBu in GF-deficient medium, compared to the culture in GF-containing medium. The effect of GF and NaBu on the change in the expression and activity of cellular proteins, c-Myc, Bcl-2 and pyruvate dehydrogenase (PDH), was also investigated. Both the withdrawal of GF and the addition of NaBu decreased the expression of c-Myc. The expression of Bcl-2 was enhanced by the addition of NaBu in a dose-dependent manner while it was not affected by the withdrawal of GF. In addition, both the withdrawal of GF and the addition of NaBu reduced metabolic rates, q(Glc), q(Lac) and Y(Lac/Glc), and increased PDH activity while not affecting PDH expression, suggesting that they may reduce the glycolytic rates, but enhance the conversion rates of pyruvate to TCA intermediates. Taken together, the withdrawal of GF in combination with the addition of NaBu can be considered as a relevant strategy for alleviating NaBu-induced cell apoptosis and enhancing antibody production since it can be easily implemented as well as enhance q(Ab) and extend culture longevity. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Intestinal hormones and growth factors: Effects on the small intestine

    PubMed Central

    Drozdowski, Laurie; Thomson, Alan BR

    2009-01-01

    There are various hormones and growth factors which may modify the intestinal absorption of nutrients, and which might thereby be useful in a therapeutic setting, such as in persons with short bowel syndrome. In partI, we focus first on insulin-like growth factors, epidermal and transferring growth factors, thyroid hormones and glucocorticosteroids. Part II will detail the effects of glucagon-like peptide (GLP)-2 on intestinal absorption and adaptation, and the potential for an additive effect of GLP2 plus steroids. PMID:19152442

  16. The Effects of Autocorrelation on the Curve-of-Factors Growth Model

    ERIC Educational Resources Information Center

    Murphy, Daniel L.; Beretvas, S. Natasha; Pituch, Keenan A.

    2011-01-01

    This simulation study examined the performance of the curve-of-factors model (COFM) when autocorrelation and growth processes were present in the first-level factor structure. In addition to the standard curve-of factors growth model, 2 new models were examined: one COFM that included a first-order autoregressive autocorrelation parameter, and a…

  17. Growth and Growth hormone - Insulin Like Growth Factor -I (GH-IGF-I) Axis in Chronic Anemias.

    PubMed

    Soliman, Ashraf T; De Sanctis, Vincenzo; Yassin, Mohamed; Adel, Ashraf

    2017-04-28

    Anaemia is a global public health problem affecting both developing and developed countries with major consequences for human health as well as social and economic development. It occurs at all stages of the life cycle, but is more prevalent in pregnant women and young children. Iron deficiency anaemia (IDA) was considered to be among the most important contributing factors to the global burden of disease. Prolonged and/or chronic anemia has a negative effect on linear growth especially during the rapid phases (infancy and puberty). Additionally infants with chronic IDA have delayed cognitive, motor, and affective development that may be long-lasting. In view of the significant impact of chronic anemias on growth, pediatricians endocrinologists and hematologists should advocate primary prevention and screening for growth disturbance in these forms of anemias. The extent of the negative effect of different forms of chronic anemias on linear growth and its possible reversibilty is addressed in this review. The possible mechanisms that may impair growth in the different forms of anemias are addressed with special attention to their effect on the growth hormone (GH) - insulin like growth factor -I (IGF-I).

  18. Sequential growth factor application in bone marrow stromal cell ligament engineering.

    PubMed

    Moreau, Jodie E; Chen, Jingsong; Horan, Rebecca L; Kaplan, David L; Altman, Gregory H

    2005-01-01

    In vitro bone marrow stromal cell (BMSC) growth may be enhanced through culture medium supplementation, mimicking the biochemical environment in which cells optimally proliferate and differentiate. We hypothesize that the sequential administration of growth factors to first proliferate and then differentiate BMSCs cultured on silk fiber matrices will support the enhanced development of ligament tissue in vitro. Confluent second passage (P2) BMSCs obtained from purified bone marrow aspirates were seeded on RGD-modified silk matrices. Seeded matrices were divided into three groups for 5 days of static culture, with medium supplement of basic fibroblast growth factor (B) (1 ng/mL), epidermal growth factor (E; 1 ng/mL), or growth factor-free control (C). After day 5, medium supplementation was changed to transforming growth factor-beta1 (T; 5 ng/mL) or C for an additional 9 days of culture. Real-time RT-PCR, SEM, MTT, histology, and ELISA for collagen type I of all sample groups were performed. Results indicated that BT supported the greatest cell ingrowth after 14 days of culture in addition to the greatest cumulative collagen type I expression measured by ELISA. Sequential growth factor application promoted significant increases in collagen type I transcript expression from day 5 of culture to day 14, for five of six groups tested. All T-supplemented samples surpassed their respective control samples in both cell ingrowth and collagen deposition. All samples supported spindle-shaped, fibroblast cell morphology, aligning with the direction of silk fibers. These findings indicate significant in vitro ligament development after only 14 days of culture when using a sequential growth factor approach.

  19. Vascular endothelial growth factor and platelet-derived growth factor are potential angiogenic and metastatic factors in human breast cancer.

    PubMed

    Anan, K; Morisaki, T; Katano, M; Ikubo, A; Kitsuki, H; Uchiyama, A; Kuroki, S; Tanaka, M; Torisu, M

    1996-03-01

    Angiogenesis is a prerequisite for tumor growth and metastasis. Tumor angiogenesis may be mediated by several angiogenic factors such as vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), transforming growth factor-alpha, and basic fibroblast growth factor. Differential mRNA expressions of VEGF, PDGF (A chain), transforming growth factor-alpha and basic fibroblast growth factor in 32 primary invasive breast tumors were examined by reverse transcriptase-polymerase chain reaction. We analyzed relationships between mRNA expressions of these angiogenic factors and the degree of angiogenesis, tumor size, and metastasis. Quantification of angiogenesis was achieved by the immunohistochemical staining of endothelial cells with antibody to CD31. VEGF and PDGF-A mRNAs were expressed more frequently in breast tumors than in nontumor breast tissues, whereas no difference was found in expression frequency of either transforming growth factor-alpha or basic fibroblast growth factor mRNA. Vascular counts in tumors correlated with each expression frequency of VEGF and PDGF-A mRNA. PDGF-A mRNA was expressed more frequently in tumors with lymph node metastasis than in those without metastasis. Expression of VEGF and PDGF mRNAs detected by reverse transcriptase-polymerase chain reaction in breast tumors correlates with tumor-related characteristics of angiogenesis and metastatic potential. Analysis of these mRNAs by reverse transcriptase-polymerase chain reaction may be useful for assessing the biologic behavior of a breast tumor before surgical treatment.

  20. Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion.

    PubMed

    Gorin, Caroline; Rochefort, Gael Y; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Muller, Laurent; Chaussain, Catherine; Germain, Stéphane

    2016-03-01

    Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. ©AlphaMed Press.

  1. Additive effects of fibroblast growth factor 23 neutralization and dietary phytase on chick calcium and phosphorus metabolism.

    PubMed

    Ren, Z Z; Bütz, D E; Wahhab, A N; Piepenburg, A J; Cook, M E

    2017-05-01

    Phytase hydrolyzes phytate rendering phosphorus available for intestinal absorption, while systemic neutralization of fibroblast growth factor 23 (FGF-23), using anti-FGF-23 antibody, has been shown to increase phosphate retention. Hence, neutralization of FGF-23 should be additive with phytase in reducing dietary non-phytate phosphorus (nPP) needs in chickens fed plant-based diets rich in phytic acid. This study was designed to test the additive effects of maternally derived anti-FGF-23 antibody and dietary phytase on the performance of chicks fed a low nPP diet from one to 14 d. Single Comb White Leghorn laying hens were vaccinated with either an adjuvant control or a synthetic FGF-23 peptide (GMNPPPYS). Chicks from vaccinated hens with control or anti-FGF-23 maternal antibodies were fed either a diet containing 0.2% nPP and 0.9% calcium with or without 500 unit phytase per kg of diet (2 × 2 factorial with main effects of antibody type and phytase addition, n = 15 pens of chicks/treatment). A significant interaction between dietary phytase and maternally derived anti-FGF-23 antibody on growth and feed efficiency was observed (P ≤ 0.05), in which chicks receiving either phytase or maternally derived anti-FGF-23 antibody had improved body weight gain (21 or 15%, respectively) and feed efficiency (16 or 18%, respectively) as compared to chicks with control antibody and not fed phytase. Both phytase and maternally derived anti-FGF-23 antibody independently increased (P ≤ 0.05) plasma phosphate (11 and 11%, respectively) and percent tibiotarsus ash (13 and 11%, respectively). Significant main effects and the lack of an interaction supported an additive effect of phytase and anti-FGF-23 antibody on plasma phosphate and percent tibiotarsus ash. Feeding phytase to chicks fed 0.2% nPP increased plasma FGF-23 levels by 22% (P ≤ 0.05); however, no effects of anti-FGF-23 antibody on plasma FGF-23 levels were observed. In conclusion, dietary phytase and presence of

  2. Friends Turned Foes: Angiogenic Growth Factors beyond Angiogenesis.

    PubMed

    Matkar, Pratiek N; Ariyagunarajah, Ramya; Leong-Poi, Howard; Singh, Krishna K

    2017-10-02

    Angiogenesis, the formation of new blood vessels from pre-existing ones is a biological process that ensures an adequate blood flow is maintained to provide the cells with a sufficient supply of nutrients and oxygen within the body. Numerous soluble growth factors and inhibitors, cytokines, proteases as well as extracellular matrix proteins and adhesion molecules stringently regulate the multi-factorial process of angiogenesis. The properties and interactions of key angiogenic molecules such as vascular endothelial growth factors (VEGFs), fibroblast growth factors (FGFs) and angiopoietins have been investigated in great detail with respect to their molecular impact on angiogenesis. Since the discovery of angiogenic growth factors, much research has been focused on their biological actions and their potential use as therapeutic targets for angiogenic or anti-angiogenic strategies in a context-dependent manner depending on the pathologies. It is generally accepted that these factors play an indispensable role in angiogenesis. However, it is becoming increasingly evident that this is not their only role and it is likely that the angiogenic factors have important functions in a wider range of biological and pathological processes. The additional roles played by these molecules in numerous pathologies and biological processes beyond angiogenesis are discussed in this review.

  3. Friends Turned Foes: Angiogenic Growth Factors beyond Angiogenesis

    PubMed Central

    Matkar, Pratiek N.; Ariyagunarajah, Ramya; Leong-Poi, Howard; Singh, Krishna K.

    2017-01-01

    Angiogenesis, the formation of new blood vessels from pre-existing ones is a biological process that ensures an adequate blood flow is maintained to provide the cells with a sufficient supply of nutrients and oxygen within the body. Numerous soluble growth factors and inhibitors, cytokines, proteases as well as extracellular matrix proteins and adhesion molecules stringently regulate the multi-factorial process of angiogenesis. The properties and interactions of key angiogenic molecules such as vascular endothelial growth factors (VEGFs), fibroblast growth factors (FGFs) and angiopoietins have been investigated in great detail with respect to their molecular impact on angiogenesis. Since the discovery of angiogenic growth factors, much research has been focused on their biological actions and their potential use as therapeutic targets for angiogenic or anti-angiogenic strategies in a context-dependent manner depending on the pathologies. It is generally accepted that these factors play an indispensable role in angiogenesis. However, it is becoming increasingly evident that this is not their only role and it is likely that the angiogenic factors have important functions in a wider range of biological and pathological processes. The additional roles played by these molecules in numerous pathologies and biological processes beyond angiogenesis are discussed in this review. PMID:28974056

  4. Epidermal growth factor- and hepatocyte growth factor-receptor activity in serum-free cultures of human hepatocytes.

    PubMed

    Runge, D M; Runge, D; Dorko, K; Pisarov, L A; Leckel, K; Kostrubsky, V E; Thomas, D; Strom, S C; Michalopoulos, G K

    1999-02-01

    Serum-free primary cultures of hepatocytes are a useful tool to study factors triggering hepatocyte proliferation and regeneration. We have developed a chemically defined serum-free system that allows human hepatocyte proliferation in the presence of epidermal growth factor and hepatocyte growth factor. DNA synthesis and accumulation were determined by [3H]thymidine incorporation and fluorometry, respectively. Western blot analyses and co-immunoprecipitations were used to investigate the association of proteins involved in epidermal growth factor and hepatocyte growth factor activation and signaling: epidermal growth factor receptor, hepatocyte growth factor receptor (MET), urokinase-type plasminogen activator and its receptor, and a member of the signal transducer and activator of transcription family, STAT-3. Primary human hepatocytes proliferated under serum-free conditions in a chemically defined medium for up to 12 days. Epidermal growth factor-receptor and MET were present and functional, decreasing over time. MET, urokinase-type plasminogen activator and urokinase-type plasminogen activator receptor co-precipitated to varying degrees during the culture period. STAT-3 co-precipitated with epidermal growth factor-receptor and MET to varying degrees. Proliferation of human hepatocytes can improve by modification of a chemically defined medium originally used for rat hepatocyte cultures. In these long-term cultures of human hepatocytes, hepatocyte growth factor and epidermal growth factor can stimulate growth and differentiation by interacting with their receptors and initiating downstream signaling. This involves complex formation of the receptors with other plasma membrane components for MET (urokinase-type plasminogen activator in context of its receptor) and activation of STAT-3 for both receptors.

  5. A role of placental growth factor in hair growth.

    PubMed

    Yoon, Sun-Young; Yoon, Ji-Seon; Jo, Seong Jin; Shin, Chang Yup; Shin, Jong-Yeon; Kim, Jong-Il; Kwon, Ohsang; Kim, Kyu Han

    2014-05-01

    The dermal papilla (DP) comprises specialized mesenchymal cells at the bottom of the hair follicle and plays a pivotal role in hair formation, anagen induction and the hair cycle. In this study, DPs were isolated from human hair follicles and serially subcultured. From each subculture at passages 1, 3, and 5 (n=4), we compared gene expression profiles using mRNA sequencing. Among the growth factors that were down-regulated in later passages of human DP cells (hDPCs), placental growth factor (PlGF) was selected. To elucidate the effect of PlGF on hair growth. We evaluated the effect of PlGF on hDPCs and on ex vivo hair organ culture. We investigated the effect of PlGF on an in vivo model of depilation-induced hair regeneration. We confirmed that the mRNA and protein expression levels of PlGF significantly decreased following subculture of the cells. It was shown that PlGF enhanced hair shaft elongation in ex vivo hair organ culture. Furthermore, PlGF significantly accelerated hair follicle growth and markedly prolonged anagen hair growth in an in vivo model of depilation-induced hair regeneration. PlGF prevented cell death by increasing the levels of phosphorylated extracellular signal-regulated kinase (ERK) and cyclin D1 and promoted survival by up-regulation of phosphorylated Akt and Bcl2, as determined by Western blotting. Our results suggest that PlGF plays a role in the promotion of hair growth and therefore may serve as an additional therapeutic target for the treatment of alopecia. Copyright © 2014 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  6. Chitosan conduits combined with nerve growth factor microspheres repair facial nerve defects

    PubMed Central

    Liu, Huawei; Wen, Weisheng; Hu, Min; Bi, Wenting; Chen, Lijie; Liu, Sanxia; Chen, Peng; Tan, Xinying

    2013-01-01

    Microspheres containing nerve growth factor for sustained release were prepared by a compound method, and implanted into chitosan conduits to repair 10-mm defects on the right buccal branches of the facial nerve in rabbits. In addition, chitosan conduits combined with nerve growth factor or normal saline, as well as autologous nerve, were used as controls. At 90 days post-surgery, the muscular atrophy on the right upper lip was more evident in the nerve growth factor and normal sa-line groups than in the nerve growth factor-microspheres and autologous nerve groups. physiological analysis revealed that the nerve conduction velocity and amplitude were significantly higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. Moreover, histological observation illustrated that the di-ameter, number, alignment and myelin sheath thickness of myelinated nerves derived from rabbits were higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. These findings indicate that chitosan nerve conduits bined with microspheres for sustained release of nerve growth factor can significantly improve facial nerve defect repair in rabbits. PMID:25206635

  7. Growth factor involvement in tension-induced skeletal muscle growth

    NASA Technical Reports Server (NTRS)

    Vandenburgh, Herman H.

    1993-01-01

    Long-term manned space travel will require a better understanding of skeletal muscle atrophy which results from microgravity. Astronaut strength and dexterity must be maintained for normal mission operations and for emergency situations. Although exercise in space slows the rate of muscle loss, it does not prevent it. A biochemical understanding of how gravity/tension/exercise help to maintain muscle size by altering protein synthesis and/or degradation rate should ultimately allow pharmacological intervention to prevent muscle atrophy in microgravity. The overall objective is to examine some of the basic biochemical processes involved in tension-induced muscle growth. With an experimental in vitro system, the role of exogenous and endogenous muscle growth factors in mechanically stimulated muscle growth are examined. Differentiated avian skeletal myofibers can be 'exercised' in tissue culture using a newly developed dynamic mechanical cell stimulator device which simulates different muscle activity patterns. Patterns of mechanical activity which significantly affect muscle growth and metabolic characteristics were found. Both exogenous and endogenous growth factors are essential for tension-induced muscle growth. Exogenous growth factors found in serum, such as insulin, insulin-like growth factors, and steroids, are important regulators of muscle protein turnover rates and mechanically-induced muscle growth. Endogenous growth factors are synthesized and released into the culture medium when muscle cells are mechanically stimulated. At least one family of mechanically induced endogenous factors, the prostaglandins, help to regulate the rates of protein turnover in muscle cells. Endogenously synthesized IGF-1 is another. The interaction of muscle mechanical activity and these growth factors in the regulation of muscle protein turnover rates with our in vitro model system is studied.

  8. Transcription factor EGR-1 suppresses the growth and transformation of human HT-1080 fibrosarcoma cells by induction of transforming growth factor beta 1.

    PubMed Central

    Liu, C; Adamson, E; Mercola, D

    1996-01-01

    The early growth response 1 (EGR-1) gene product is a transcription factor with role in differentiation and growth. We have previously shown that expression of exogenous EGR-1 in various human tumor cells unexpectedly and markedly reduces growth and tumorigenicity and, conversely, that suppression of endogenous Egr-1 expression by antisense RNA eliminates protein expression, enhances growth, and promotes phenotypic transformation. However, the mechanism of these effects remained unknown. The promoter of human transforming growth factor beta 1 (TGF-beta 1) contains two GC-rich EGR-1 binding sites. We show that expression of EGR-1 in human HT-1080 fibrosarcoma cells uses increased secretion of biologically active TGF-beta 1 in direct proportion (rPearson = 0.96) to the amount of EGR-1 expressed and addition of recombinant human TGF-beta 1 is strongly growth-suppressive for these cells. Addition of monoclonal anti-TGF-beta 1 antibodies to EGR-1-expressing HT-1080 cells completely reverses the growth inhibitory effects of EGR-1. Reporter constructs bearing the EGR-1 binding segment of the TGF-beta 1 promoter was activated 4- to 6-fold relative to a control reporter in either HT-1080 cells that stably expressed or parental cells cotransfected with an EGR-1 expression vector. Expression of delta EGR-1, a mutant that cannot interact with the corepressors, nerve growth factor-activated factor binding proteins NAB1 and NAB2, due to deletion of the repressor domain, exhibited enhanced transactivation of 2- to 3.5-fold over that of wild-type EGR-1 showing that the reporter construct reflected the appropriate in vivo regulatory context. The EGR-1-stimulated transactivation was inhibited by expression of the Wilms tumor suppressor, a known specific DNA-binding competitor. These results indicate that EGR-1 suppresses growth of human HT-1080 fibrosarcoma cells by induction of TGF-beta 1. Images Fig. 1 Fig. 5 PMID:8876223

  9. Insulin-like growth factor-I and growth differentiation factor-5 promote the formation of tissue-engineered human nasal septal cartilage.

    PubMed

    Alexander, Thomas H; Sage, August B; Chen, Albert C; Schumacher, Barbara L; Shelton, Elliot; Masuda, Koichi; Sah, Robert L; Watson, Deborah

    2010-10-01

    Tissue engineering of human nasal septal chondrocytes offers the potential to create large quantities of autologous material for use in reconstructive surgery of the head and neck. Culture with recombinant human growth factors may improve the biochemical and biomechanical properties of engineered tissue. The objectives of this study were to (1) perform a high-throughput screen to assess multiple combinations of growth factors and (2) perform more detailed testing of candidates identified in part I. In part I, human nasal septal chondrocytes from three donors were expanded in monolayer with pooled human serum (HS). Cells were then embedded in alginate beads for 2 weeks of culture in medium supplemented with 2% or 10% HS and 1 of 90 different growth factor combinations. Combinations of insulin-like growth factor-I (IGF-1), bone morphogenetic protein (BMP)-2, BMP-7, BMP-13, growth differentiation factor-5 (GDF-5), transforming growth factor β (TGFβ)-2, insulin, and dexamethasone were evaluated. Glycosaminoglycan (GAG) accumulation was measured. A combination of IGF-1 and GDF-5 was selected for further testing based on the results of part I. Chondrocytes from four donors underwent expansion followed by three-dimensional alginate culture for 2 weeks in medium supplemented with 2% or 10% HS with or without IGF-1 and GDF-5. Chondrocytes and their associated matrix were then recovered and cultured for 4 weeks in 12 mm transwells in medium supplemented with 2% or 10% HS with or without IGF-1 and GDF-5 (the same medium used for alginate culture). Biochemical and biomechanical properties of the neocartilage were measured. In part I, GAG accumulation was highest for growth factor combinations including both IGF-1 and GDF-5. In part II, the addition of IGF-1 and GDF-5 to 2% HS resulted in a 12-fold increase in construct thickness compared with 2% HS alone (p < 0.0001). GAG and type II collagen accumulation was significantly higher with IGF-1 and GDF-5. Confined compression

  10. Growth factors and myometrium: biological effects in uterine fibroid and possible clinical implications

    PubMed Central

    Ciarmela, Pasquapina; Islam, Md. Soriful; Reis, Fernando M.; Gray, Peter C.; Bloise, Enrrico; Petraglia, Felice; Vale, Wylie; Castellucci, Mario

    2011-01-01

    BACKGROUND Growth factors are proteins secreted by a number of cell types that are capable of modulating cellular growth, proliferation and cellular differentiation. It is well accepted that uterine cellular events such as proliferation and differentiation are regulated by sex steroids and their actions in target tissues are mediated by local production of growth factors acting through paracrine and/or autocrine mechanisms. Myometrial mass is ultimately modified in pregnancy as well as in tumour conditions such as leiomyoma and leiomyosarcoma. Leiomyomas, also known as fibroids, are benign tumours of the uterus, considered to be one of the most frequent causes of infertility in reproductive years in women. METHODS For this review, we searched the database MEDLINE and Google Scholar for articles with content related to growth factors acting on myometrium; the findings are hereby reviewed and discussed. RESULTS Different growth factors such as epidermal growth factor (EGF), transforming growth factor-α (TGF-α), heparin-binding EGF (HB-EGF), acidic fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), platelet-derived growth factor (PDGF) and TGF-β perform actions in myometrium and in leiomyomas. In addition to these growth factors, activin and myostatin have been recently identified in myometrium and leiomyoma. CONCLUSIONS Growth factors play an important role in the mechanisms involved in myometrial patho-physiology. PMID:21788281

  11. Regulation of cell growth by redox-mediated extracellular proteolysis of platelet-derived growth factor receptor beta.

    PubMed

    Okuyama, H; Shimahara, Y; Kawada, N; Seki, S; Kristensen, D B; Yoshizato, K; Uyama, N; Yamaoka, Y

    2001-07-27

    Redox-regulated processes are important elements in various cellular functions. Reducing agents, such as N-acetyl-l-cysteine (NAC), are known to regulate signal transduction and cell growth through their radical scavenging action. However, recent studies have shown that reactive oxygen species are not always involved in ligand-stimulated intracellular signaling. Here, we report a novel mechanism by which NAC blocks platelet-derived growth factor (PDGF)-induced signaling pathways in hepatic stellate cells, a fibrogenic player in the liver. Unlike in vascular smooth muscle cells, we found that reducing agents, including NAC, triggered extracellular proteolysis of PDGF receptor-beta, leading to desensitization of hepatic stellate cells toward PDGF-BB. This effect was mediated by secreted mature cathepsin B. In addition, type II transforming growth factor-beta receptor was also down-regulated. Furthermore, these events seemed to cause a dramatic improvement of rat liver fibrosis. These results indicated that redox processes impact the cell's response to growth factors by regulating the turnover of growth factor receptors and that "redox therapy" is promising for fibrosis-related disease.

  12. Growth factor-functionalized silk membranes support wound healing in vitro.

    PubMed

    Bienert, M; Hoss, M; Bartneck, M; Weinandy, S; Böbel, M; Jockenhövel, S; Knüchel, R; Pottbacker, K; Wöltje, M; Jahnen-Dechent, W; Neuss, S

    2017-08-16

    Chronic wounds represent a serious problem in daily medical routine requiring improved wound care. Silk of the domesticated silkworm (Bombyx mori) has been used to form a variety of biomaterials for medical applications. We genetically engineered B. mori to produce silk functionalized with growth factors to promote wound healing in vitro. In this study FGF-, EGF-, KGF-, PDGF- or VEGF-functionalized silk membranes were compared to native B. mori silk membranes without growth factors for their ability to support wound healing in vitro. All silk membranes were cytocompatible and supported macrophage secretion of neutrophil recruiting factor CXCL1 and monocyte chemoattractant protein 1 (MCP-1). VEGF-functionalized silk significantly outperformed other growth factor-functionalized silk membranes, but not native silk in angiogenesis assays. In addition, EGF- and VEGF-functionalized silk membranes slightly enhanced macrophage adhesion compared to silk without growth factors. In wound healing assays in vitro (reduction of wound lesion), dermal equivalents showed a higher wound healing capacity when covered with EGF-, FGF- or VEGF-functionalized silk membranes compared to native, KGF- or PDGF-functionalized silk membranes. Keratinocyte migration and growth is overstimulated by KGF- and VEGF-functionalized silk membranes. In conclusion, growth factor-functionalized silk membranes prepared from genetically engineered silk worm glands are promising wound dressings for future wound healing therapies.

  13. The Effects of Hematopoietic Growth Factors on Neurite Outgrowth

    PubMed Central

    Su, Ye; Cui, Lili; Piao, Chunshu; Li, Bin; Zhao, Li-Ru

    2013-01-01

    Stem cell factor (SCF) and granulocyte colony-stimulating factor (G-CSF) are initially discovered as the essential hematopoietic growth factors regulating bone marrow stem cell proliferation and differentiation, and SCF in combination with G-CSF (SCF+G-CSF) has synergistic effects on bone marrow stem cell mobilization. In this study we have determined the effect of SCF and G-CSF on neurite outgrowth in rat cortical neurons. Using molecular and cellular biology and live cell imaging approaches, we have revealed that receptors for SCF and G-CSF are expressed on the growth core of cortical neurons, and that SCF+G-CSF synergistically enhances neurite extension through PI3K/AKT and NFκB signaling pathways. Moreover, SCF+G-CSF induces much greater NFκB activation, NFκB transcriptional binding and brain-derived neurotrophic factor (BDNF) production than SCF or G-CSF alone. In addition, we have also observed that BDNF, the target gene of NFκB, is required for SCF+G-CSF-induced neurite outgrowth. These data suggest that SCF+G-CSF has synergistic effects to promote neurite growth. This study provides new insights into the contribution of hematopoietic growth factors in neuronal plasticity. PMID:24116056

  14. Neonatal hyperthyroidism impairs epinephrine-provoked secretion of nerve growth factor and epidermal growth factor in mouse saliva.

    PubMed

    Lakshmanan, J; Landel, C P

    1986-07-01

    We examined long-term effects of neonatal hyperthyroidism on salivary secretions of nerve growth factor and epidermal growth factor in male and female mice at the age of 31 days. Hyperthyroidism was induced by thyroxine (T4) injections (0.4 microgram/g body weight/day) during days 0-6. Littermate control mice were treated with vehicle. T4 treatment did not alter the amounts of protein secreted into saliva but hormone administration induced alteration in the types of protein secreted. T4 treatment decreased the contents of both nerve growth factor and epidermal growth factor secreted into the saliva. A Sephadex G-200 column chromatographic profile revealed the presence of two distinct nerve growth factor immunoreactive peaks, while epidermal growth factor immunoreactivity predominantly eluted as a single low molecular weight form. T4 treatment did not alter the molecular nature of their secretion, but the treatment decreased their contents. These results indicate an impairment in salivary secretion of nerve growth factor and epidermal growth factor long after T4 treatment has been discontinued.

  15. Liposomal gene transfer of keratinocyte growth factor improves wound healing by altering growth factor and collagen expression.

    PubMed

    Pereira, Clifford T; Herndon, David N; Rocker, Roland; Jeschke, Marc G

    2007-05-15

    Growth factors affect the complex cascade of wound healing; however, interaction between different growth factors during dermal and epidermal regeneration are still not entirely defined. In the present study, we thought to determine the interaction between keratinocyte growth factor (KGF) administered as liposomal cDNA with other dermal and epidermal growth factors and collagen synthesis in an acute wound. Rats received an acute wound and were divided into two groups to receive weekly subcutaneous injections of liposomes plus the Lac-Z gene (0.22 microg, vehicle), or liposomes plus the KGF cDNA (2.2 microg) and Lac-Z gene (0.22 microg). Histological and immunohistochemical techniques were used to determine growth factor, collagen expression, and dermal and epidermal structure. KGF cDNA increased insulin-like growth factor-I (IGF-I), insulin-like growth factor binding protein-3 (IGFBP-3), and fibroblast growth factor (FGF), decreased transforming growth factor-beta (TGF-beta), while it had no effect on platelet-derived growth factor (PDGF) levels in the wound. KGF cDNA significantly increased collagen Type IV at both the wound edge as well as the wound bed, while it had no effect on collagen Type I and III. KGF cDNA increased re-epithelialization, improved dermal regeneration, and increased neovascularization. Exogenous administered KGF cDNA causes increases in IGF-I, IGF-BP3, FGF, and collagen IV and decreases TGF-beta concentration. KGF gene transfer accelerates wound healing without causing an increase in collagen I or III.

  16. Increased Melanoma Growth and Metastasis Spreading in Mice Overexpressing Placenta Growth Factor

    PubMed Central

    Marcellini, Marcella; De Luca, Naomi; Riccioni, Teresa; Ciucci, Alessandro; Orecchia, Angela; Lacal, Pedro Miguel; Ruffini, Federica; Pesce, Maurizio; Cianfarani, Francesca; Zambruno, Giovanna; Orlandi, Augusto; Failla, Cristina Maria

    2006-01-01

    Placenta growth factor (PlGF), a member of the vascular endothelial growth factor family, plays an important role in adult pathological angiogenesis. To further investigate PlGF functions in tumor growth and metastasis formation, we used transgenic mice overexpressing PlGF in the skin under the control of the keratin 14 promoter. These animals showed a hypervascularized phenotype of the skin and increased levels of circulating PlGF with respect to their wild-type littermates. Transgenic mice and controls were inoculated intradermally with B16-BL6 melanoma cells. The tumor growth rate was fivefold increased in transgenic animals compared to wild-type mice, in the presence of a similar percentage of tumor necrotic tissue. Tumor vessel area was increased in transgenic mice as compared to controls. Augmented mobilization of endothelial and hematopoietic stem cells from the bone marrow was observed in transgenic animals, possibly contributing to tumor vascularization. The number and size of pulmonary metastases were significantly higher in transgenic mice compared to wild-type littermates. Finally, PlGF promoted tumor cell invasion of the extracellular matrix and increased the activity of selected matrix metalloproteinases. These findings indicate that PlGF, in addition to enhancing tumor angiogenesis and favoring tumor growth, may directly influence melanoma dissemination. PMID:16877362

  17. The glial growth factors deficiency and synaptic destabilization hypothesis of schizophrenia.

    PubMed

    Moises, Hans W; Zoega, Tomas; Gottesman, Irving I

    2002-07-03

    A systems approach to understanding the etiology of schizophrenia requires a theory which is able to integrate genetic as well as neurodevelopmental factors. Based on a co-localization of loci approach and a large amount of circumstantial evidence, we here propose that a functional deficiency of glial growth factors and of growth factors produced by glial cells are among the distal causes in the genotype-to-phenotype chain leading to the development of schizophrenia. These factors include neuregulin, insulin-like growth factor I, insulin, epidermal growth factor, neurotrophic growth factors, erbB receptors, phosphatidylinositol-3 kinase, growth arrest specific genes, neuritin, tumor necrosis factor alpha, glutamate, NMDA and cholinergic receptors. A genetically and epigenetically determined low baseline of glial growth factor signaling and synaptic strength is expected to increase the vulnerability for additional reductions (e.g., by viruses such as HHV-6 and JC virus infecting glial cells). This should lead to a weakening of the positive feedback loop between the presynaptic neuron and its targets, and below a certain threshold to synaptic destabilization and schizophrenia. Supported by informed conjectures and empirical facts, the hypothesis makes an attractive case for a large number of further investigations. The hypothesis suggests glial cells as the locus of the genes-environment interactions in schizophrenia, with glial asthenia as an important factor for the genetic liability to the disorder, and an increase of prolactin and/or insulin as possible working mechanisms of traditional and atypical neuroleptic treatments.

  18. New microbial growth factor

    NASA Technical Reports Server (NTRS)

    Bok, S. H.; Casida, L. E., Jr.

    1977-01-01

    A screening procedure was used to isolate from soil a Penicillium sp., two bacterial isolates, and a Streptomyces sp. that produced a previously unknown microbial growth factor. This factor was an absolute growth requirement for three soil bacteria. The Penicillium sp. and one of the bacteria requiring the factor, an Arthrobacter sp., were selected for more extensive study concerning the production and characteristics of the growth factor. It did not seem to be related to the siderochromes. It was not present in soil extract, rumen fluid, or any other medium component tested. It appears to be a glycoprotein of high molecular weight and has high specific activity. When added to the diets for a meadow-vole mammalian test system, it caused an increased consumption of diet without a concurrent increase in rate of weight gain.

  19. Insulin-like growth factor-I receptor activity is essential for Kaposi's sarcoma growth and survival.

    PubMed

    Catrina, S-B; Lewitt, M; Massambu, C; Dricu, A; Grünler, J; Axelson, M; Biberfeld, P; Brismar, K

    2005-04-25

    Kaposi's sarcoma (KS) is a highly vascular tumour and is the most common neoplasm associated with human immunodeficiency virus (HIV-1) infection. Growth factors, in particular vascular endothelial growth factor (VEGF), have been shown to play an important role in its development. The role of insulin-like growth factors (IGFs) in the pathophysiology of different tumours led us to evaluate the role of IGF system in KS. The IGF-I receptors (IGF-IR) were identified by immunohistochemistry in biopsies taken from patients with different AIDS/HIV-related KS stages and on KSIMM cells (an established KS-derived cell line). Insulin-like growth factor-I is a growth factor for KSIMM cells with a maximum increase of 3H-thymidine incorporation of 130 +/- 27.6% (P < 0.05) similar to that induced by VEGF and with which it is additive (281 +/- 13%) (P < 0.05). Moreover, specific blockade of the receptor (either by alpha IR3 antibody or by picropodophyllin, a recently described selective IGF-IR tyrosine phosphorylation inhibitor) induced KSIMM apoptosis, suggesting that IGF-IR agonists (IGF-I and -II) mediate antiapoptotic signals for these cells. We were able to identify an autocrine loop essential for KSIMM cell survival in which IGF-II is the IGF-IR agonist secreted by the cells. In conclusion, IGF-I pathway inhibition is a promising therapeutical approach for KS tumours.

  20. Insulin-like growth factors in embryonic and fetal growth and skeletal development (Review).

    PubMed

    Agrogiannis, Georgios D; Sifakis, Stavros; Patsouris, Efstratios S; Konstantinidou, Anastasia E

    2014-08-01

    The insulin-like growth factors (IGF)-I and -II have a predominant role in fetal growth and development. IGFs are involved in the proliferation, differentiation and apoptosis of fetal cells in vitro and the IGF serum concentration has been shown to be closely correlated with fetal growth and length. IGF transcripts and peptides have been detected in almost every fetal tissue from as early in development as pre‑implantation to the final maturation stage. Furthermore, IGFs have been demonstrated to be involved in limb morphogenesis. However, although ablation of Igf genes in mice resulted in growth retardation and delay in skeletal maturation, no impact on outgrowth and patterning of embryonic limbs was observed. Additionally, various molecular defects in the Igf1 and Igf1r genes in humans have been associated with severe intrauterine growth retardation and impaired skeletal maturation, but not with truncated limbs or severe skeletal dysplasia. The conflicting data between in vitro and in vivo observations with regard to bone morphogenesis suggests that IGFs may not be the sole trophic factors involved in fetal skeletal growth and that redundant mechanisms may exist in chondro- and osteogenesis. Further investigation is required in order to elucidate the functions of IGFs in skeletal development.

  1. Factors That Influence Language Growth.

    ERIC Educational Resources Information Center

    McCarthy, Dorothea, Ed.; And Others

    This booklet contains four articles that discuss factors influencing language growth. The first, "The Child's Equipment for Language Growth" by Charlotte Wells, examines what the child needs for language learning, how the child uses his equipment for language growth, and what school factors facilitate the child's use of his equipment for language…

  2. Fibroblast growth factor receptor signaling crosstalk in skeletogenesis.

    PubMed

    Miraoui, Hichem; Marie, Pierre J

    2010-11-02

    Fibroblast growth factors (FGFs) play important roles in the control of embryonic and postnatal skeletal development by activating signaling through FGF receptors (FGFRs). Germline gain-of-function mutations in FGFR constitutively activate FGFR signaling, causing chondrocyte and osteoblast dysfunctions that result in skeletal dysplasias. Crosstalk between the FGFR pathway and other signaling cascades controls skeletal precursor cell differentiation. Genetic analyses revealed that the interplay of WNT and FGFR1 determines the fate and differentiation of mesenchymal stem cells during mouse craniofacial skeletogenesis. Additionally, interactions between FGFR signaling and other receptor tyrosine kinase networks, such as those mediated by the epidermal growth factor receptor and platelet-derived growth factor receptor α, were associated with excessive osteoblast differentiation and bone formation in the human skeletal dysplasia called craniosynostosis, which is a disorder of skull development. We review the roles of FGFR signaling and its crosstalk with other pathways in controlling skeletal cell fate and discuss how this crosstalk could be pharmacologically targeted to correct the abnormal cell phenotype in skeletal dysplasias caused by aberrant FGFR signaling.

  3. Insulin-like growth factor 1: common mediator of multiple enterotrophic hormones and growth factors.

    PubMed

    Bortvedt, Sarah F; Lund, P Kay

    2012-03-01

    To summarize the recent evidence that insulin-like growth factor 1 (IGF1) mediates growth effects of multiple trophic factors and discuss clinical relevance. Recent reviews and original reports indicate benefits of growth hormone (GH) and long-acting glucagon-like peptide 2 (GLP2) analogs in short bowel syndrome and Crohn's disease. This review highlights the evidence that biomarkers of sustained small intestinal growth or mucosal healing and evaluation of intestinal epithelial stem cell biomarkers may improve clinical measures of intestinal growth or response to trophic hormones. Compelling evidence that IGF1 mediates growth effects of GH and GLP2 on intestine or linear growth in preclinical models of resection or Crohn's disease is presented, along with a concept that these hormones or IGF1 may enhance sustained growth if given early after bowel resection. Evidence that suppressor of cytokine signaling protein induction by GH or GLP2 in normal or inflamed intestine may limit IGF1-induced growth, but protect against risk of dysplasia or fibrosis, is reviewed. Whether IGF1 receptor mediates IGF1 action and potential roles of insulin receptors are addressed. IGF1 has a central role in mediating trophic hormone action in small intestine. Better understanding of benefits and risks of IGF1, receptors that mediate IGF1 action, and factors that limit undesirable growth are needed.

  4. The glial growth factors deficiency and synaptic destabilization hypothesis of schizophrenia

    PubMed Central

    Moises, Hans W; Zoega, Tomas; Gottesman, Irving I

    2002-01-01

    Background A systems approach to understanding the etiology of schizophrenia requires a theory which is able to integrate genetic as well as neurodevelopmental factors. Presentation of the hypothesis Based on a co-localization of loci approach and a large amount of circumstantial evidence, we here propose that a functional deficiency of glial growth factors and of growth factors produced by glial cells are among the distal causes in the genotype-to-phenotype chain leading to the development of schizophrenia. These factors include neuregulin, insulin-like growth factor I, insulin, epidermal growth factor, neurotrophic growth factors, erbB receptors, phosphatidylinositol-3 kinase, growth arrest specific genes, neuritin, tumor necrosis factor alpha, glutamate, NMDA and cholinergic receptors. A genetically and epigenetically determined low baseline of glial growth factor signaling and synaptic strength is expected to increase the vulnerability for additional reductions (e.g., by viruses such as HHV-6 and JC virus infecting glial cells). This should lead to a weakening of the positive feedback loop between the presynaptic neuron and its targets, and below a certain threshold to synaptic destabilization and schizophrenia. Testing the hypothesis Supported by informed conjectures and empirical facts, the hypothesis makes an attractive case for a large number of further investigations. Implications of the hypothesis The hypothesis suggests glial cells as the locus of the genes-environment interactions in schizophrenia, with glial asthenia as an important factor for the genetic liability to the disorder, and an increase of prolactin and/or insulin as possible working mechanisms of traditional and atypical neuroleptic treatments. PMID:12095426

  5. FGF growth factor analogs

    DOEpatents

    Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY; Takahashi, Kazuyuki [Germantown, MD

    2012-07-24

    The present invention provides a fibroblast growth factor heparin-binding analog of the formula: ##STR00001## where R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, X, Y and Z are as defined, pharmaceutical compositions, coating compositions and medical devices including the fibroblast growth factor heparin-binding analog of the foregoing formula, and methods and uses thereof.

  6. Growth factors in porcine full and partial thickness burn repair. Differing targets and effects of keratinocyte growth factor, platelet-derived growth factor-BB, epidermal growth factor, and neu differentiation factor.

    PubMed Central

    Danilenko, D. M.; Ring, B. D.; Tarpley, J. E.; Morris, B.; Van, G. Y.; Morawiecki, A.; Callahan, W.; Goldenberg, M.; Hershenson, S.; Pierce, G. F.

    1995-01-01

    The topical application of recombinant growth factors such as epidermal growth factor, platelet-derived growth factor-BB homodimer (rPDGF-BB), keratinocyte growth factor (rKGF), and neu differentiation factor has resulted in significant acceleration of healing in several animal models of wound repair. In this study, we established highly reproducible and quantifiable full and deep partial thickness porcine burn models in which burns were escharectomized 4 or 5 days postburn and covered with an occlusive dressing to replicate the standard treatment in human burn patients. We then applied these growth factors to assess their efficacy on several parameters of wound repair: extracellular matrix and granulation tissue production, percent reepithelialization, and new epithelial area. In full thickness burns, only rPDGF-BB and the combination of rPDGF-BB and rKGF induced significant changes in burn repair. rPDGF-BB induced marked extracellular matrix and granulation tissue production (P = 0.013) such that the burn defect was filled within several days of escharectomy, but had no effect on new epithelial area or reepithelialization. The combination of rPDGF-BB and rKGF in full thickness burns resulted in a highly significant increase in extracellular matrix and granulation tissue area (P = 0.0009) and a significant increase in new epithelial area (P = 0.007), but had no effect on reepithelialization. In deep partial thickness burns, rKGF induced the most consistent changes. Daily application of rKGF induced a highly significant increase in new epithelial area (P < 0.0001) but induced only a modest increase in reepithelialization (83.7% rKGF-treated versus 70.2% control; P = 0.016) 12 days postburn. rKGF also doubled the number of fully reepithelialized burns (P = 0.02) at 13 days postburn, at least partially because of marked stimulation of both epidermal and follicular proliferation as assessed by proliferating cell nuclear antigen expression. In situ hybridization for

  7. Regulation of Transforming Growth Factor β1, Platelet-Derived Growth Factor, and Basic Fibroblast Growth Factor by Silicone Gel Sheeting in Early-Stage Scarring.

    PubMed

    Choi, Jaehoon; Lee, Eun Hee; Park, Sang Woo; Chang, Hak

    2015-01-01

    Hypertrophic scars and keloids are associated with abnormal levels of growth factors. Silicone gel sheets are effective in treating and preventing hypertrophic scars and keloids. There has been no report on the change in growth factors in the scar tissue following the use of silicone gel sheeting for scar prevention. A prospective controlled trial was performed to evaluate whether growth factors are altered by the application of a silicone gel sheet on a fresh surgical scar. Four of seven enrolled patients completed the study. Transforming growth factor (TGF)-β1, platelet-derived growth factor (PDGF), and basic fibroblast growth factor (bFGF) were investigated immunohistochemically in biopsies taken from five scars at 4 months following surgery. In both the epidermis and the dermis, the expression of TGF-β1 (P=0.042 and P=0.042) and PDGF (P=0.043 and P=0.042) was significantly lower in the case of silicone gel sheet-treated scars than in the case of untreated scars. The expression of bFGF in the dermis was significantly higher in the case of silicone gel sheet-treated scars than in the case of untreated scars (P=0.042), but in the epidermis, the expression of bFGF showed no significant difference between the groups (P=0.655). The levels of TGF-β1, PDGF, and bFGF are altered by the silicone gel sheet treatment, which might be one of the mechanisms of action in scar prevention.

  8. Growth factors, nutrient signaling, and cardiovascular aging.

    PubMed

    Fontana, Luigi; Vinciguerra, Manlio; Longo, Valter D

    2012-04-13

    Growth factors regulated by specific macronutrients have been shown to promote aging and accelerate mortality in the majority of the organisms studied. In particular, the enzymes activated by growth hormone, insulin, and insulin-like growth factor-1 in mammals and their orthologs in simple model organisms represent perhaps the best-understood proteins involved in the aging process. Dietary restriction, which reduces the level of insulin-like growth factor-1 and of other growth factors, has been associated with protection from diabetes, cancer, and cardiovascular diseases, and deficiencies in growth hormone signaling and insulin-like growth factor-1 are strongly associated with protection from cancer and diabetes in both mice and humans; however, their role in cardiac function and cardiovascular diseases is controversial. Here, we review the link between growth factors, cardiac function, and heart disease with focus on the cardioprotective and sensitizing effect of growth factors in both model organisms and humans.

  9. Growth/differentiation factor-11: an evolutionary conserved growth factor in vertebrates.

    PubMed

    Funkenstein, Bruria; Olekh, Elena

    2010-11-01

    Growth and differentiation factor-11 (GDF-11) is a member of the transforming growth factor-β superfamily and is thought to be derived together with myostatin (known also as GDF-8) from an ancestral gene. In the present study, we report the isolation and characterization of GDF-11 homolog from a marine teleost, the gilthead sea bream Sparus aurata, and show that this growth factor is highly conserved throughout vertebrates. Using bioinformatics, we identified GDF-11 in Tetraodon, Takifugu, medaka, and stickleback and found that they are highly conserved at the amino acid sequence as well as gene organization. Moreover, we found conservation of syntenic relationships among vertebrates in the GDF-11 locus. Transcripts for GDF-11 can be found in eggs and early embryos, albeit at low levels, while in post-hatching larvae expression levels are high and decreases as development progresses, suggesting that GDF-11 might have a role during early development of fish as found in tetrapods and zebrafish. Finally, GDF-11 is expressed in various tissues in the adult fish including muscle, brain, and eye.

  10. Insulin-Like Growth Factor and Epidermal Growth Factor Signaling in Breast Cancer Cell Growth: Focus on Endocrine Resistant Disease

    PubMed Central

    Berdiaki, Aikaterini; Tzardi, Maria

    2015-01-01

    Breast cancer is the most common type of cancer for women worldwide with a lifetime risk amounting to a staggering total of 10%. It is well established that the endogenous synthesis of insulin-like growth factor (IGF) and epidermal growth factor (EGF) polypeptide growth factors are closely correlated to malignant transformation and all the steps of the breast cancer metastatic cascade. Numerous studies have demonstrated that both estrogens and growth factors stimulate the proliferation of steroid-dependent tumor cells, and that the interaction between these signaling pathways occurs at several levels. Importantly, the majority of breast cancer cases are estrogen receptor- (ER-) positive which have a more favorable prognosis and pattern of recurrence with endocrine therapy being the backbone of treatment. Unfortunately, the majority of patients progress to endocrine therapy resistant disease (acquired resistance) whereas a proportion of patients may fail to respond to initial therapy (de novo resistance). The IGF-I and EGF downstream signaling pathways are closely involved in the process of progression to therapy resistant disease. Modifications in the bioavailability of these growth factors contribute critically to disease progression. In the present review therefore, we will discuss in depth how IGF and EGF signaling participate in breast cancer pathogenesis and progression to endocrine resistant disease. PMID:26258011

  11. The importance of neuronal growth factors in the ovary.

    PubMed

    Streiter, S; Fisch, B; Sabbah, B; Ao, A; Abir, R

    2016-01-01

    The neurotrophin family consists of nerve growth factor (NGF), neurotrophin 3 (NT3) and neurotrophin 4/5 (NT4/5), in addition to brain-derived neurotrophic factor (BDNF) and the neuronal growth factors, glial cell line-derived neurotrophic factor (GDNF) and vasointestinal peptide (VIP). Although there are a few literature reviews, mainly of animal studies, on the importance of neurotrophins in the ovary, we aimed to provide a complete review of neurotrophins as well as neuronal growth factors and their important roles in normal and pathological processes in the ovary. Follicular assembly is probably stimulated by complementary effects of NGF, NT4/5 and BDNF and their receptors. The neurotrophins, GDNF and VIP and their receptors have all been identified in preantral and antral follicles of mammalian species, including humans. Transgenic mice with mutations in the genes encoding for Ngf, Nt4/5 and Bdnf and their tropomyosin-related kinase β receptor showed a reduction in preantral follicles and an abnormal ovarian morphology, whereas NGF, NT3, GDNF and VIP increased the in vitro activation of primordial follicles in rats and goats. Additionally, NGF, NT3 and GDNF promoted follicular cell proliferation; NGF, BDNF and VIP were shown to be involved in ovulation; VIP inhibited follicular apoptosis; NT4/5, BDNF and GDNF promoted oocyte maturation and NGF, NT3 and VIP stimulated steroidogenesis. NGF may also exert a stimulatory effect in ovarian cancer and polycystic ovarian syndrome (PCOS). Low levels of NGF and BDNF in follicular fluid may be associated with diminished ovarian reserve and high levels with endometriosis. More knowledge of the roles of neuronal growth factors in the ovary has important implications for the development of new therapeutic drugs (such as anti-NGF agents) for ovarian cancer and PCOS as well as various infertility problems, warranting further research. © The Author 2015. Published by Oxford University Press on behalf of the European Society

  12. Growth factors for nanobacteria

    NASA Astrophysics Data System (ADS)

    Ciftcioglu, Neva; Kajander, E. Olavi

    1999-12-01

    Nanobacteria are novel microorganisms recently isolated from fetal bovine serum and blood of cows and humans. These coccoid, gram negative bacteria in alpha-2 subgroup of Proteobacteria grow slowly under mammalian cell culture conditions but not in common media for microbes. Now we have found two different kinds of culture supplement preparations that improve their growth and make them culturable in the classical sense. These are supernatant fractions of conditioned media obtained from 1 - 3 months old nanobacteria cultures and from about a 2 weeks old Bacillus species culture. Both improved multiplication and particle yields and the latter increased their resistance to gentamicin. Nanobacteria cultured with any of the methods shared similar immunological property, structure and protein pattern. The growth supporting factors were heat-stabile and nondialyzable, and dialysis improved the growth promoting action. Nanobacteria formed stony colonies in a bacteriological medium supplemented with the growth factors. This is an implication that nanobacterial growth is influenced by pre-existing bacterial flora.

  13. Growth Factors and Tension-Induced Skeletal Muscle Growth

    NASA Technical Reports Server (NTRS)

    Vandenburgh, Herman H.

    1994-01-01

    The project investigated biochemical mechanisms to enhance skeletal muscle growth, and developed a computer based mechanical cell stimulator system. The biochemicals investigated in this study were insulin/(Insulin like Growth Factor) IGF-1 and Steroids. In order to analyze which growth factors are essential for stretch-induced muscle growth in vitro, we developed a defined, serum-free medium in which the differentiated, cultured avian muscle fibers could be maintained for extended periods of time. The defined medium (muscle maintenance medium, MM medium) maintains the nitrogen balance of the myofibers for 3 to 7 days, based on myofiber diameter measurements and myosin heavy chain content. Insulin and IGF-1, but not IGF-2, induced pronounced myofiber hypertrophy when added to this medium. In 5 to 7 days, muscle fiber diameters increase by 71 % to 98% compared to untreated controls. Mechanical stimulation of the avian muscle fibers in MM medium increased the sensitivity of the cells to insulin and IGF-1, based on a leftward shift of the insulin dose/response curve for protein synthesis rates. (54). We developed a ligand binding assay for IGF-1 binding proteins and found that the avian skeletal muscle cultures produced three major species of 31, 36 and 43 kD molecular weight (54) Stretch of the myofibers was found to have no significant effect on the efflux of IGF-1 binding proteins, but addition of exogenous collagen stimulated IGF-1 binding protein production 1.5 to 5 fold. Steroid hormones have a profound effect on muscle protein turnover rates in vivo, with the stress-related glucocorticoids inducing rapid skeletal muscle atrophy while androgenic steroids induce skeletal muscle growth. Exercise in humans and animals reduces the catabolic effects of glucocorticoids and may enhance the anabolic effects of androgenic steroids on skeletal muscle. In our continuing work on the involvement of exogenrus growth factors in stretch-induced avian skeletal muscle growth, we

  14. Research on growth factors in periodontology.

    PubMed

    Smith, Patricio C; Martínez, Constanza; Cáceres, Mónica; Martínez, Jorge

    2015-02-01

    Growth factors play critical roles in periodontal repair through the regulation of cell behavior. Many of the cell responses regulated by these proteins include cell adhesion, migration, proliferation and differentiation. Periodontal regeneration involves an organized response of different cells, tissues and growth factors implicated in the coordination of these events. However, periodontal tissue reconstruction is an extremely difficult task. Multiple studies have been performed to understand the specific role of growth factors in periodontal wound healing. In the present review we analyze the evidence that supports the roles of growth factors in periodontal wound healing and regeneration. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Fibroblast growth factor-2-induced host stroma reaction during initial tumor growth promotes progression of mouse melanoma via vascular endothelial growth factor A-dependent neovascularization.

    PubMed

    Tsunoda, Satoshi; Nakamura, Toshiyuki; Sakurai, Hiroaki; Saiki, Ikuo

    2007-04-01

    Fibroblast growth factor (FGF)-2 has been considered to play a critical role in neovascularization in several tumors; however, its precise role in tumor progression is not fully understood. In the present study, we have characterized the role of FGF-2 in B16-BL6 mouse melanoma cells, focusing on effects during the initial phase of tumor growth. FGF-2 was injected at the tumor inoculation site of dorsal skin during the initial phase. FGF-2 induced marked tumor growth and lymph node metastasis. This was well correlated with an increase in neovascularization in the host stroma. FGF-2 also recruited inflammatory and mesenchymal cells in host stroma. Marked tumor growth, pulmonary metastasis and intensive neovascularization in tumor parenchyma were also observed after a single injection of FGF-2 into the footpad inoculation site. In contrast, repeated injections of FGF-2 at a site remote from the footpad tumor were ineffective in promoting tumor growth and metastasis. These promoting activities of FGF-2 were blocked by local injections of a glucocorticoid hormone, suggesting that host inflammatory responses induced by FGF-2 are associated with FGF-2-induced tumor progression. In addition, although FGF-2 did not promote cellular proliferation and vascular endothelial growth factor A (VEGFA) mRNA expression in B16-BL6 cells in vitro, FGF-2 induced VEGFA expression in host stroma rather than tumor tissue, and local injections of a neutralizing antibody against VEGFA inhibited these activities of FGF-2 in vivo. These results indicate that abundant FGF-2 during the initial phase of tumor growth induces VEGFA-dependent intensive neovascularization in host stroma, and supports marked tumor growth and metastasis.

  16. Synthetic heparin-binding growth factor analogs

    DOEpatents

    Pena, Louis A.; Zamora, Paul; Lin, Xinhua; Glass, John D.

    2007-01-23

    The invention provides synthetic heparin-binding growth factor analogs having at least one peptide chain that binds a heparin-binding growth factor receptor, covalently bound to a hydrophobic linker, which is in turn covalently bound to a non-signaling peptide that includes a heparin-binding domain. The synthetic heparin-binding growth factor analogs are useful as soluble biologics or as surface coatings for medical devices.

  17. Fibroblast growth factor regulates insulin-like growth factor-binding protein production by vascular smooth muscle cells.

    PubMed

    Ververis, J; Ku, L; Delafontaine, P

    1994-02-01

    Insulin-like growth factor I is an important mitogen for vascular smooth muscle cells, and its effects are regulated by several binding proteins. Western ligand blotting of conditioned medium from rat aortic smooth muscle cells detected a 24 kDa binding protein and a 28 kDa glycosylated variant of this protein, consistent with insulin-like growth factor binding protein-4 by size. Low amounts of a glycosylated 38 to 42 kDa doublet (consistent with binding protein-3) and a 31 kDa non-glycosylated protein also were present. Basic fibroblast growth factor markedly increased secretion of the 24 kDa binding protein and its 28 kDa glycosylated variant. This effect was dose- and time-dependent and was inhibited by co-incubation with cycloheximide. Crosslinking of [125I]-insulin-like growth factor I to cell monolayers revealed no surface-associated binding proteins, either basally or after agonist treatment. Induction of binding protein production by fibroblast growth factor at sites of vascular injury may be important in vascular proliferative responses in vivo.

  18. Expression of transforming growth factor alpha and epidermal growth factor receptor messenger RNA in neoplastic and nonneoplastic human kidney tissue.

    PubMed

    Mydlo, J H; Michaeli, J; Cordon-Cardo, C; Goldenberg, A S; Heston, W D; Fair, W R

    1989-06-15

    Using Northern blot analysis, we have demonstrated that mRNA for transforming growth factor alpha (TGF-alpha) was expressed in five malignant kidney tissue specimens but was not detected in their autologous nonneoplastic homologues. In addition, the expression of epidermal growth factor (EGF) receptor mRNA in these malignant tissues was 2- to 3-fold greater than in nontransformed tissues. In two cases examined using immunohistochemistry, we were able to correlate the increased expression of the mRNA with an increase in protein expression. Since TGF-alpha is known to bind to the EGF receptor, the finding of an increased expression of both TGF-alpha and EGF receptor mRNA in kidney tumor tissue suggests that interaction between TGF-alpha and the EGF receptor may play a role in promoting transformation and/or proliferation of kidney neoplasms, perhaps by an autocrine mechanism.

  19. Oxygen-sensitive regulation and neuroprotective effects of growth hormone-dependent growth factors during early postnatal development.

    PubMed

    Jung, Susan; Boie, Gudrun; Doerr, Helmuth-Guenther; Trollmann, Regina

    2017-04-01

    Perinatal hypoxia severely disrupts metabolic and somatotrophic development, as well as cerebral maturational programs. Hypoxia-inducible transcription factors (HIFs) represent the most important endogenous adaptive mechanisms to hypoxia, activating a broad spectrum of growth factors that contribute to cell survival and energy homeostasis. To analyze effects of systemic hypoxia and growth hormone (GH) therapy (rhGH) on HIF-dependent growth factors during early postnatal development, we compared protein (using ELISA) and mRNA (using quantitative RT PCR) levels of growth factors in plasma and brain between normoxic and hypoxic mice (8% O 2 , 6 h; postnatal day 7 , P7) at P14. Exposure to hypoxia led to reduced body weight ( P < 0.001) and length ( P < 0.04) compared with controls and was associated with significantly reduced plasma levels of mouse GH ( P < 0.01) and IGF-1 ( P < 0.01). RhGH abrogated these hypoxia-induced changes of the GH/IGF-1 axis associated with normalization of weight and length gain until P14 compared with controls. In addition, rhGH treatment increased cerebral IGF-1, IGF-2, IGFBP-2, and erythropoietin mRNA levels, resulting in significantly reduced apoptotic cell death in the hypoxic, developing mouse brain. These data indicate that rhGH may functionally restore hypoxia-induced systemic dysregulation of the GH/IGF-1 axis and induce upregulation of neuroprotective, HIF-dependent growth factors in the hypoxic developing brain. Copyright © 2017 the American Physiological Society.

  20. Autocrine expression of the epidermal growth factor receptor ligand heparin-binding EGF-like growth factor in cervical cancer.

    PubMed

    Schrevel, Marlies; Osse, E Michelle; Prins, Frans A; Trimbos, J Baptist M Z; Fleuren, Gert Jan; Gorter, Arko; Jordanova, Ekaterina S

    2017-06-01

    In cervical cancer, the epidermal growth factor receptor (EGFR) is overexpressed in 70-90% of the cases and has been associated with poor prognosis. EGFR-based therapy is currently being explored in cervical cancer. We investigated which EGFR ligand is primarily expressed in cervical cancer and which cell type functions as the major source of this ligand. We hypothesized that macrophages are the main source of EGFR ligands and that a paracrine loop between tumor cells and macrophages is responsible for ligand expression. mRNA expression analysis was performed on 32 cervical cancer cases to determine the expression of the EGFR ligands amphiregulin, β-cellulin, epidermal growth factor (EGF), epiregulin, heparin-binding EGF-like growth factor (HB‑EGF) and transforming growth factor α (TGFα). Subsequently, protein expression was determined immunohistochemically on 36 additional cases. To assess whether macrophages are the major source of EGFR ligands, immunohistochemical double staining was performed on four representative tissue slides. Expression of the chemokines granulocyte-macrophage colony-stimulating factor (GM-CSF) and C-C motif ligand 2 (CCL2) was determined by mRNA in situ hybridization. Of the known EGFR ligands, HB‑EGF had the highest mRNA expression and HB‑EGF and EGFR protein expression were highly correlated. Tumor specimens with high EGFR expression showed higher numbers of macrophages, and higher expression of GM-CSF and CCL2, but only a small subset (9%) of macrophages was found to be HB‑EGF-positive. Strikingly, 78% of cervical cancer specimens were found to express HB‑EGF. Standardized assessment of staining intensity, using spectral imaging analysis, showed that HB‑EGF expression was higher in the tumor compartment than in the stromal compartment. These results suggest that HB‑EGF is an important EGFR ligand in cervical cancer and that cervical cancer cells are the predominant source of HB‑EGF. Therefore, we propose an autocrine

  1. 48 CFR 1352.271-72 - Additional Item Requirements (AIR)-growth work

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Requirements (AIR)-growth work 1352.271-72 Section 1352.271-72 Federal Acquisition Regulations System... Clauses 1352.271-72 Additional Item Requirements (AIR)—growth work As prescribed in 48 CFR 1371.103, insert the following clause: Additional Item Requirements (Air)—Growth Work (APR 2010) (a) This clause...

  2. The Influence of Platelet-Derived Growth Factor and Fibroblast Growth Factor 2 on Oligodendrocyte Development and Remyelination

    DTIC Science & Technology

    2004-01-01

    OLIGODENDROCYTE DEVELOPMENT AND REMYELINATION 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e...Z39-18 ABSTRACT Title: THE INFLUENCE OF PLATELET-DERIVED GROWTH FACTOR AND FIBROBLAST GROWTH FACTOR 2 ON OLIGODENDROCYTE DEVELOPMENT AND...GROWTH FACTOR 2 ON OLIGODENDROCYTE DEVELOPMENT AND REMYELINATION by Joshua C. Murtie Thesis/dissertation submitted to the

  3. Ligand-Independent Epidermal Growth Factor Receptor Overexpression Correlates with Poor Prognosis in Colorectal Cancer.

    PubMed

    Yun, Sumi; Kwak, Yoonjin; Nam, Soo Kyung; Seo, An Na; Oh, Heung-Kwon; Kim, Duck-Woo; Kang, Sung-Bum; Lee, Hye Seung

    2018-01-17

    Molecular treatments targeting epidermal growth factor receptors (EGFRs) are important strategies for advanced colorectal cancer (CRC). However, clinicopathologic implications of EGFRs and EGFR ligand signaling have not been fully evaluated. We evaluated the expression of EGFR ligands and correlation with their receptors, clinicopathologic factors, and patients' survival with CRC. The expression of EGFR ligands, including heparin binding epidermal growth factor like growth factor (HBEGF), transforming growth factor (TGF), betacellulin, and epidermal growth factor (EGF), were evaluated in 331 consecutive CRC samples using mRNA in situ hybridization (ISH). We also evaluated the expression status of EGFR, human epidermal growth factor receptor 2 (HER2), HER3, and HER4 using immunohistochemistry and/or silver ISH. Unlike low incidences of TGF (38.1%), betacellulin (7.9%), and EGF (2.1%), HBEGF expression was noted in 62.2% of CRC samples. However, the expression of each EGFR ligand did not reveal significant correlations with survival. The combined analyses of EGFR ligands and EGFR expression indicated that the ligands‒/EGFR+ group showed a significant association with the worst disease-free survival (DFS, p=0.018) and overall survival (OS, p=0.005). It was also an independent, unfavorable prognostic factor for DFS (p=0.026) and OS (p=0.007). Additionally, HER4 nuclear expression, regardless of ligand expression, was an independent, favorable prognostic factor for DFS (p=0.034) and OS (p=0.049), by multivariate analysis. Ligand-independent EGFR overexpression was suggested to have a significant prognostic impact; thus, the expression status of EGFR ligands, in addition to EGFR, might be necessary for predicting patients' outcome in CRC.

  4. Transforming growth factor (TGF. beta. ) decreases the proliferation of human bone marrow fibroblasts by inhibiting the platelet-derived growth factor (PDGF) binding

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bryckaert, M.C.; Tobelem, G.; Lindroth, M.

    1988-12-01

    Human bone marrow fibroblasts were cultivated and characterized by immunofluorescent staining and electron microscopy. Their interactions with PDGF and TGF{beta} were studied. While a positive intracellular antifibronectin staining was observed, the cultured cells were not labeled with specific antibodies toward factor VIII von Willebrand factor (F VIII/vWF), desmin, and macrophage antigen. The binding of pure human PDGF to the cultured bone marrow fibroblasts was investigated. Addition of an excess of unlabeled PDGF decreased the binding to 75 and 80%, which means that the nonspecific binding represented 20-25% of total binding, whereas epidermal growth factor (EGF) had no effect. Two classesmore » of sites were detected by Scatchard analysis. The stimulation of DNA synthesis of PDGF was quantified by ({sup 3}H)thymidine incorporation. The results suggested that PDGF and TGF{beta} could modulate the growth of bone marrow fibroblasts.« less

  5. Growth factor transgenes interactively regulate articular chondrocytes.

    PubMed

    Shi, Shuiliang; Mercer, Scott; Eckert, George J; Trippel, Stephen B

    2013-04-01

    Adult articular chondrocytes lack an effective repair response to correct damage from injury or osteoarthritis. Polypeptide growth factors that stimulate articular chondrocyte proliferation and cartilage matrix synthesis may augment this response. Gene transfer is a promising approach to delivering such factors. Multiple growth factor genes regulate these cell functions, but multiple growth factor gene transfer remains unexplored. We tested the hypothesis that multiple growth factor gene transfer selectively modulates articular chondrocyte proliferation and matrix synthesis. We tested the hypothesis by delivering combinations of the transgenes encoding insulin-like growth factor I (IGF-I), fibroblast growth factor-2 (FGF-2), transforming growth factor beta1 (TGF-β1), bone morphogenetic protein-2 (BMP-2), and bone morphogenetic protien-7 (BMP-7) to articular chondrocytes and measured changes in the production of DNA, glycosaminoglycan, and collagen. The transgenes differentially regulated all these chondrocyte activities. In concert, the transgenes interacted to generate widely divergent responses from the cells. These interactions ranged from inhibitory to synergistic. The transgene pair encoding IGF-I and FGF-2 maximized cell proliferation. The three-transgene group encoding IGF-I, BMP-2, and BMP-7 maximized matrix production and also optimized the balance between cell proliferation and matrix production. These data demonstrate an approach to articular chondrocyte regulation that may be tailored to stimulate specific cell functions, and suggest that certain growth factor gene combinations have potential value for cell-based articular cartilage repair. Copyright © 2012 Wiley Periodicals, Inc.

  6. Improving In Vitro Generated Cartilage-Carrier-Constructs by Optimizing Growth Factor Combination

    PubMed Central

    Wiegandt, Katharina; Goepfert, Christiane; Pörtner, Ralf

    2007-01-01

    The presented study is focused on the generation of osteochondral implants for cartilage repair, which consist of bone substitutes covered with in vitro engineered cartilage. Re-differentiation of expanded porcine cells was performed in alginate gel followed by cartilage formation in high-density cell cultures. In this work, different combinations of growth factors for the stimulation of re-differentiation and cartilage formation have been tested to improve the quality of osteochondral implants. It has been demonstrated that supplementation of the medium with growth factors has significant effects on the properties of the matrix. The addition of the growth factors IGF-I (100 ng/mL) and TGF-β1 (10 ng/mL) during the alginate culture and the absence of any growth factors during the high-density cell culture led to significantly higher GAG to DNA ratios and Young’s Moduli of the constructs compared to other combinations. The histological sections showed homogenous tissue and intensive staining for collagen type II. PMID:19662133

  7. 14 CFR 1203.406 - Additional classification factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROGRAM Guides for Original Classification § 1203.406 Additional classification factors. In determining the appropriate classification category, the following additional factors should be considered: (a... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Additional classification factors. 1203.406...

  8. Reduced growth factor requirement of keloid-derived fibroblasts may account for tumor growth

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Russell, S.B.; Trupin, K.M.; Rodriguez-Eaton, S.

    Keloids are benign dermal tumors that form during an abnormal wound-healing process is genetically susceptible individuals. Although growth of normal and keloid cells did not differ in medium containing 10% (vol/vol) fetal bovine serum, keloid culture grew to significantly higher densities than normal cells in medium containing 5% (vol/vol) fetal bovine serum, keloid cultures grew to significantly higher densities than normal cells in medium containing 5% (vol/vol) plasma or 1% fetal bovine serum. Conditioned medium from keloid cultures did not stimulate growth of normal cells in plasma nor did it contain detectable platelet-derived growth factor or epidermal growth factor. Keloidmore » fibroblasts responded differently than normal adult fibroblasts to transforming growth factor ..beta... Whereas transforming growth factor ..beta.. reduced growth stimulation by epidermal growth factor in cells from normal adult skin or scars, it enhanced the activity of epidermal growth factor in cells from normal adult skin or scars, it enhanced the activity of epidermal growth factor in cells from keloids. Normal and keloid fibroblasts also responded differently to hydrocortisone: growth was stimulated in normal adult cells and unaffected or inhibited in keloid cells. Fetal fibroblasts resembled keloid cells in their ability to grow in plasma and in their response to hydrocortisone. The ability of keloid fibroblasts to grow to higher cell densities in low-serum medium than cells from normal adult skin or from normal early or mature scars suggests that a reduced dependence on serum growth factors may account for their prolonged growth in vivo. Similarities between keloid and fetal cells suggest that keloids may result from the untimely expression of growth-control mechanism that is developmentally regulated.« less

  9. Bone-Derived Growth Factors

    PubMed Central

    Capanna, R.; Campanacci, D.A.; De Biase, P.; Cuomo, P.; Lorenzoni, A.

    2010-01-01

    Bone regeneration is based on the synergy between osteconduction, osteoinduction and osteogenesis. In recent years, we have witnessed the birth and development of numerous osteoconductive substrates, created with the intention of replacing bone grafts, both autologous and homologous. Recently, attention has shifted to osteogenesis, in other words, to the study of mesenchymal cells and their differentiation into osteoblastic cell lines that can be cultured in vitro (as already seen with chondroblasts). Osteoinduction, too, has been shown to be equally important, ever since Urist’s 1967 study which drew attention to the demineralised bone matrix and its properties. The following twenty years led to the definition of bone morphogenetic protein (BMP) and finally to the marketing of the first ostegenic protein (OP-1) obtained by means of the gene recombination technique. The BMPs produced using this technique that, so far, have been shown to be most active are BMP-2 (Infuse) and BMP-7 (Osigraft). The BMPs are not the only molecules with osteoinductive capacity. Other molecules capable of influencing bone regeneration are: platelet-derived growth factors (PDGFs), the transforming growth factor-beta (TGF-β) family, insulin-like growth factor (IGF-I) and the acidic and basic fibroblast growth factors (FGFs). All these growth factors act in synergy with the BMPs, modulating their action and exerting an inductive and proliferative action on the cell lines responsible for regenerating the bone matrix. The literature has been literally invaded by studies, both experimental and preclinical, on these proteins (Termaat, 2005), and they have provided ample demonstration that the BMPs are effective in improving healing of fractures, pseudoarthrosis and spinal fusions. Important advantages of BMPs are the complete absence of risk of transmissible disease, given that they are produced using recombination technology; their purity, and thus absence of an immune response (although

  10. Expression of Epidermal Growth Factor Receptor and Transforming Growth Factor Alpha in Cancer Bladder: Schistosomal and Non-Schistosomal

    PubMed Central

    Badawy, Afkar A.; El-Hindawi, Ali; Hammam, Olfat; Moussa, Mona; Helal, Noha S.; Kamel, Amira

    2017-01-01

    Introduction Overexpression of epidermal growth factor receptor (EGFR) has been described in several solid tumors including bladder cancer. Transforming growth factor alpha (TGFα) is frequently deregulated in neoplastic cells and plays a role in the development of bladder cancer. TGFα-EGFR ligand-receptor combination constitutes an important event in multistep tumorigenesis. Methods This study was done on 30 bladder biopsies from patients with urothelial carcinoma, 15 with squamous cell carcinoma, 10 with cystitis and 5 normal control bladder specimens. All were immuohistochemically stained with EGFR and TGFα antibodies. Results EGFR and TGFα were over-expressed in higher grades and late stages of bladder cancer. Moreover, they show higher expression in squamous cell carcinoma compared to urothelial carcinoma and in schistosomal associated lesions than in non-schistosomal associated lesions. Conclusion EGFR and TGFα could be used as prognostic predictors in early stage and grade of bladder cancer cases, especially those with schistosomal association. In addition they can help in selecting patients who can get benefit from anti-EGFR molecular targeted therapy. PMID:28413380

  11. Casein kinase 2 and the cell response to growth factors.

    PubMed

    Filhol-Cochet, O; Loue-Mackenbach, P; Cochet, C; Chambaz, E M

    1994-01-01

    Different approaches have been followed with the aim of delineating a possible role of casein kinase 2 (CK2) in the mitogenic signalling in response to cell growth factors. (a) Immunocytochemical detection of CK2 showed that while the kinase is evenly distributed throughout cycle arrested cells, it becomes preferentially associated with the nuclear compartment in activity growing cells; (b) CK2 biosynthesis is activated as an early response of quiescent cells to growth factors. The newly synthesized CK2 steadily accumulates as the cells progress through the G1 phase. This growth factor-induced CK2 biosynthesis involves in parallel the two alpha and beta subunits of the kinase, with no detectable preferential subcellular localization of the newly synthesized enzyme; and (c) In addition to substrate phosphorylation, CK2 may form molecular complexes with cell components of functional significance. Such is the case with the protein p53, a major negative regulator of the cell cycle. CK2 forms a high affinity association (Kd 70 nM) with p53, through its beta subunit. The complex dissociates in the presence of adenosine triphosphate (ATP). These observations suggest that CK2 and p53 may play a coordinated regulatory role in the cell response to growth factors.

  12. Minimally invasive esthetic ridge preservation with growth-factor enhanced bone matrix.

    PubMed

    Nevins, Marc L; Said, Sherif

    2017-12-28

    Extraction socket preservation procedures are critical to successful esthetic implant therapy. Conventional surgical approaches are technique sensitive and often result in alteration of the soft tissue architecture, which then requires additional corrective surgical procedures. This case series report presents the ability of flapless surgical techniques combined with a growth factor-enhanced bone matrix to provide esthetic ridge preservation at the time of extraction for compromised sockets. When considering esthetic dental implant therapy, preservation, or further enhancement of the available tissue support at the time of tooth extraction may provide an improved esthetic outcome with reduced postoperative sequelae and decreased treatment duration. Advances in minimally invasive surgical techniques combined with recombinant growth factor technology offer an alternative for bone reconstruction while maintaining the gingival architecture for enhanced esthetic outcome. The combination of freeze-dried bone allograft (FDBA) and rhPDGF-BB (platelet-derived growth factor-BB) provides a growth-factor enhanced matrix to induce bone and soft tissue healing. The use of a growth-factor enhanced matrix is an option for minimally invasive ridge preservation procedures for sites with advanced bone loss. Further studies including randomized clinical trials are needed to better understand the extent and limits of these procedures. The use of minimally invasive techniques with growth factors for esthetic ridge preservation reduces patient morbidity associated with more invasive approaches and increases the predictability for enhanced patient outcomes. By reducing the need for autogenous bone grafts the use of this technology is favorable for patient acceptance and ease of treatment process for esthetic dental implant therapy. © 2017 Wiley Periodicals, Inc.

  13. Growth factors, nutrient signaling, and cardiovascular aging

    PubMed Central

    Fontana, Luigi; Vinciguerra, Manlio; Longo, Valter D.

    2012-01-01

    Growth factors regulated by specific macronutrients have been shown to promote aging and accelerate mortality in the great majority of the organisms studied. In particular, the enzymes activated by growth hormone (GH), insulin and insulin-like growth factor 1 (IGF-I) in mammals and their orthologs in simple model organisms represent perhaps the best-understood proteins involved in the aging process. Dietary restriction (DR), which reduces the level of IGF-I and of other growth factors, has been associated with protection from diabetes, cancer, and cardiovascular diseases and deficiencies in GH signaling and IGF-I are strongly associated with protection from cancer and diabetes in both mice and humans, but their role in cardiac function and cardiovascular diseases is controversial. Here we review the link between growth factors, cardiac function and heart disease with focus on the cardioprotective and sensitizing effect of growth factors in both model organisms and humans. PMID:22499903

  14. Identification of interleukin-6 as an autocrine growth factor for Epstein-Barr virus-immortalized B cells.

    PubMed Central

    Tosato, G; Tanner, J; Jones, K D; Revel, M; Pike, S E

    1990-01-01

    Autocrine growth factors are believed to be important for maintenance of an immortalized state by Epstein-Barr virus (EBV), because cell-free supernatants of EBV-immortalized cell lines promote the proliferation of autologous cells and permit their growth at low cell density. In this study, we provide evidence for the existence of two autocrine growth factor activities produced by EBV-immortalized lines distinguished by size and biological activities. Much of the autocrine growth factor activity in lymphoblastoid cell line supernatants resided in a low-molecular-weight (less than 5,000) fraction. However, up to 20 to 30% of the autocrine growth factor activity resided in the high-molecular-weight (greater than 5,000) fraction. While the nature of the low-molecular-weight growth factor activity remains undefined, the high-molecular-weight growth factor activity was identified as interleukin-6 (IL-6). Culture supernatants from six EBV-induced lymphoblastoid cell lines tested contained IL-6 activity, because they promoted proliferation in the IL-6-dependent hybridoma cell line B9. In addition, a rabbit antibody to human IL-6 neutralized the capacity of the high-molecular-weight (greater than 5,000) fraction of a lymphoblastoid cell line supernatant to promote growth both in autologous EBV-immortalized cells and in B9 cells. Similarly, this high-molecular-weight autocrine growth factor activity was neutralized by a monoclonal antibody to human IL-6. Furthermore, characteristic bands, attributable to IL-6, were visualized in supernatants of each of four EBV-induced lymphoblastoid cell lines after immunoprecipitation with a rabbit antiserum to human IL-6. Thus, in addition to its previously reported properties, IL-6 is an autocrine growth factor for EBV-immortalized B cells cultured under serum-free conditions. Images PMID:2159561

  15. Role of epidermal growth factor and transforming growth factor α in the developing stomach

    PubMed Central

    Kelly, E; Newell, S; Brownlee, K; Farmery, S; Cullinane, C; Reid, W; Jackson, P; Gray, S; Primrose, J; Lagopoulos, M

    1997-01-01

    AIMS—To determine whether epidermal growth factor (EGF) or the related transforming growth factor α (TGFα) may have a role in the developing human stomach; to substantiate the presence of EGF in human liquor in the non-stressed infant and whether EGF in amniotic fluid is maternally or fetally derived.
METHODS—The temporal expression and localisation of EGF, TGFα, and their receptors during fetal and neonatal life were examined in 20 fetal and five infant stomachs. Simultaneously, samples of amniotic fluid and fetal urine from 10 newborn infants were collected and assayed for EGF by radioimmunoassay.
RESULTS—EGF immunoreactivity was not noted in any of the specimens examined. In contrast, TGFα immunoreactivity was shown in mucous cells from 18 weeks of gestation onwards. EGF receptor immunoreactivity was seen on superficial mucous cells in gastric mucosa from 18 weeks of gestation onwards. The median concentration of EGF was 30 and 8.5 pg/ml in amniotic fluid and fetal urine, respectively, suggesting that EGF is not produced by the fetus.
CONCLUSIONS—This study adds weight to the hypothesis that swallowed EGF, probably produced by the amniotic membranes, and locally produced TGFα, may have a role in the growth and maturation of the human stomach.

 Keywords: epidermal growth factor; transforming growth factor α; EGF receptors; stomach PMID:9175944

  16. Extrinsic Factors Influencing Fetal Deformations and Intrauterine Growth Restriction

    PubMed Central

    Moh, Wendy; Graham, John M.; Wadhawan, Isha; Sanchez-Lara, Pedro A.

    2012-01-01

    The causes of intrauterine growth restriction (IUGR) are multifactorial with both intrinsic and extrinsic influences. While many studies focus on the intrinsic pathological causes, the possible long-term consequences resulting from extrinsic intrauterine physiological constraints merit additional consideration and further investigation. Infants with IUGR can exhibit early symmetric or late asymmetric growth abnormality patterns depending on the fetal stage of development, of which the latter is most common occurring in 70–80% of growth-restricted infants. Deformation is the consequence of extrinsic biomechanical factors interfering with normal growth, functioning, or positioning of the fetus in utero, typically arising during late gestation. Biomechanical forces play a critical role in the normal morphogenesis of most tissues. The magnitude and direction of force impact the form of the developing fetus, with a specific tissue response depending on its pliability and stage of development. Major uterine constraining factors include primigravida, small maternal size, uterine malformation, uterine fibromata, early pelvic engagement of the fetal head, aberrant fetal position, oligohydramnios, and multifetal gestation. Corrective mechanical forces similar to those that gave rise to the deformation to reshape the deformed structures are often used and should take advantage of the rapid postnatal growth to correct form. PMID:22888434

  17. Epidermal growth factor-like growth factors prevent apoptosis of alcohol-exposed human placental cytotrophoblast cells.

    PubMed

    Wolff, Garen S; Chiang, Po Jen; Smith, Susan M; Romero, Roberto; Armant, D Randall

    2007-07-01

    Maternal alcohol abuse during pregnancy can produce an array of birth defects comprising fetal alcohol syndrome. A hallmark of fetal alcohol syndrome is intrauterine growth retardation, which is associated with elevated apoptosis of placental cytotrophoblast cells. Using a human first trimester cytotrophoblast cell line, we examined the relationship between exposure to ethanol and cytotrophoblast survival, as well as the ameliorating effects of epidermal growth factor (EGF)-like growth factors produced by human cytotrophoblast cells. After exposure to 0-100 mM ethanol, cell death was quantified by the TUNEL method, and expression of the nuclear proliferation marker, Ki67, was measured by immunohistochemistry. The mode of cell death was determined by assessing annexin V binding, caspase 3 activation, pyknotic nuclear morphology, reduction of TUNEL by caspase inhibition, and cellular release of lactate dehydrogenase. Ethanol significantly reduced proliferation and increased cell death approximately 2.5-fold through the apoptotic pathway within 1-2 h of exposure to 50 mM alcohol. Exposure to 25-50 mM ethanol significantly increased transforming growth factor alpha (TGFA) and heparin-binding EGF-like growth factor (HBEGF), but not EGF or amphiregulin (AREG). When cytotrophoblasts were exposed concurrently to 100 mM ethanol and 1 nM HBEGF or TGFA, the increase in apoptosis was prevented, while EGF ameliorated at 10 nM and AREG was weakly effective. HBEGF survival-promoting activity required ligation of either of its cognate receptors, HER1 or HER4. These findings reveal the potential for ethanol to rapidly induce cytotrophoblast apoptosis. However, survival factor induction could provide cytotrophoblasts with an endogenous cytoprotective mechanism.

  18. Growth factor and pro-inflammatory cytokine contents in platelet-rich plasma (PRP), plasma rich in growth factors (PRGF), advanced platelet-rich fibrin (A-PRF), and concentrated growth factors (CGF).

    PubMed

    Masuki, Hideo; Okudera, Toshimitsu; Watanebe, Taisuke; Suzuki, Masashi; Nishiyama, Kazuhiko; Okudera, Hajime; Nakata, Koh; Uematsu, Kohya; Su, Chen-Yao; Kawase, Tomoyuki

    2016-12-01

    The development of platelet-rich fibrin (PRF) drastically simplified the preparation procedure of platelet-concentrated biomaterials, such as platelet-rich plasma (PRP), and facilitated their clinical application. PRF's clinical effectiveness has often been demonstrated in pre-clinical and clinical studies; however, it is still controversial whether growth factors are significantly concentrated in PRF preparations to facilitate wound healing and tissue regeneration. To address this matter, we performed a comparative study of growth factor contents in PRP and its derivatives, such as advanced PRF (A-PRF) and concentrated growth factors (CGF). PRP and its derivatives were prepared from the same peripheral blood samples collected from healthy donors. A-PRF and CGF preparations were homogenized and centrifuged to produce extracts. Platelet and white blood cell counts in A-PRF and CGF preparations were determined by subtracting those counts in red blood cell fractions, supernatant acellular serum fractions, and A-PRF/CGF exudate fractions from those counts of whole blood samples. Concentrations of growth factors (TGF-β1, PDGF-BB, VEGF) and pro-inflammatory cytokines (IL-1β, IL-6) were determined using ELISA kits. Compared to PRP preparations, both A-PRF and CGF extracts contained compatible or higher levels of platelets and platelet-derived growth factors. In a cell proliferation assay, both A-PRF and CGF extracts significantly stimulated the proliferation of human periosteal cells without significant reduction at higher doses. These data clearly demonstrate that both A-PRF and CGF preparations contain significant amounts of growth factors capable of stimulating periosteal cell proliferation, suggesting that A-PRF and CGF preparations function not only as a scaffolding material but also as a reservoir to deliver certain growth factors at the site of application.

  19. Serum placental growth factor, vascular endothelial growth factor, soluble vascular endothelial growth factor receptor-1 and -2 levels in periodontal disease, and adverse pregnancy outcomes.

    PubMed

    Sert, Tuba; Kırzıoğlu, F Yeşim; Fentoğlu, Ozlem; Aylak, Firdevs; Mungan, Tamer

    2011-12-01

    The aim of this study is the evaluation of levels of serum interleukin (IL)-1β, IL-6, IL-10, tumor necrosis factor (TNF)-α, vascular endothelial growth factor (VEGF), placental growth factor (PIGF), and soluble VEGF receptor (sVEGFR)-1 and -2 in the association between periodontal disease and adverse pregnancy outcomes. One hundred and nine mothers, who recently gave birth, and 51 women who were not recently pregnant, aged 18 to 35 years, were included in this study. The mothers were classified as term birth, preterm birth (PTB), and preterm low birth weight (PLBW) in respect to their gestational age and baby's birth weight. The birth mothers were grouped as having gingivitis or periodontitis. The non-pregnant group also included periodontally healthy patients. Venous blood samples were collected to evaluate serum IL-1β, IL-6, IL-10, TNF-α, VEGF, PIGF, and sVEGFR-1 and -2 levels. Mother's weight, education, and income level were significantly associated with pregnancy outcomes. Serum levels of IL-1β, TNF-α, IL-6, VEGF, and sVEGFR-1 and -2 showed an increase in significance when related to pregnancy. Whereas in the PLBW group IL-1β, VEGF, and sVEGFR-2 levels were increased, in the PTB group sVEGFR-1 levels were increased. Additionally, the patients in the PLBW group with periodontitis had higher serum levels of IL-1β, VEGF, sVEGFR-2, and IL-1β/IL-10. The serum levels of IL-1β, VEGF, and sVEGFR-1 and -2 may have a potential effect on the mechanism of the association between periodontal disease and adverse pregnancy outcomes.

  20. Growth factors, muscle function, and doping.

    PubMed

    Goldspink, Geoffrey; Wessner, Barbara; Tschan, Harald; Bachl, Norbert

    2010-03-01

    This article discusses the inevitable use of growth factors for enhancing muscle strength and athletic performance. Much effort has been expended on developing a treatment of muscle wasting associated with a range of diseases and aging. Frailty in the aging population is a major socioeconomic and medical problem. Emerging molecular techniques have made it possible to gain a better understanding of the growth factor genes and how they are activated by physical activity. The ways that misuse of growth factors may be detected and verified in athletes and future challenges for detecting manipulation of signaling pathways are discussed. Copyright 2010. Published by Elsevier Inc.

  1. Response to Growth Hormone Treatment in a Patient with Insulin-Like Growth Factor 1 Receptor Deletion

    PubMed Central

    Mahmoud, Ranim; Naidu, Ajanta; Risheg, Hiba; Kimonis, Virginia

    2017-01-01

    We report a six-year-old boy who presented with short stature, microcephaly, dysmorphic features, and developmental delay and who was identified with a terminal deletion of 15q26.2q26.3 containing the insulin-like growth factor receptor (IGF1R) gene in addition to a terminal duplication of the 4q35.1q35.2 region. We compare our case with other reports of deletions and mutations affecting the IGF1R gene associated with pre-and postnatal growth restriction. We report the dramatic response to growth hormone therapy in this patient which highlights the importance of identifying patients with IGF1R deletion and treating them early. PMID:28720553

  2. Response to Growth Hormone Treatment in a Patient with Insulin-Like Growth Factor 1 Receptor Deletion.

    PubMed

    Mahmoud, Ranim; Naidu, Ajanta; Risheg, Hiba; Kimonis, Virginia

    2017-12-15

    We report a six-year-old boy who presented with short stature, microcephaly, dysmorphic features, and developmental delay and who was identified with a terminal deletion of 15q26.2q26.3 containing the insulin-like growth factor receptor (IGF1R) gene in addition to a terminal duplication of the 4q35.1q35.2 region. We compare our case with other reports of deletions and mutations affecting the IGF1R gene associated with pre-and postnatal growth restriction. We report the dramatic response to growth hormone therapy in this patient which highlights the importance of identifying patients with IGF1R deletion and treating them early.

  3. Growth factors and chronic wound healing: past, present, and future.

    PubMed

    Goldman, Robert

    2004-01-01

    Growth substances (cytokines and growth factors) are soluble signaling proteins affecting the process of normal wound healing. Cytokines govern the inflammatory phase that clears cellular and extracellular matrix debris. Wound repair is controlled by growth factors (platelet-derived growth factor [PDGF], keratinocyte growth factor, and transforming growth factor beta). Endogenous growth factors communicate across the dermal-epidermal interface. PDGF is important for most phases of wound healing. Becaplermin (PDGF-BB), the only growth factor approved by the Food and Drug Administration, requires daily application for neuropathic wound healing. Gene therapy is under development for more efficient growth factor delivery; a single application will induce constitutive growth factor expression for weeks. Based on dramatic preclinical animal studies, a phase 1 clinical trial planned on a PDGF genetic construct appears promising.

  4. Predictive factors for intrauterine growth restriction

    PubMed Central

    Albu, AR; Anca, AF; Horhoianu, VV; Horhoianu, IA

    2014-01-01

    Abstract Reduced fetal growth is seen in about 10% of the pregnancies but only a minority has a pathological background and is known as intrauterine growth restriction or fetal growth restriction (IUGR / FGR). Increased fetal and neonatal mortality and morbidity as well as adult pathologic conditions are often associated to IUGR. Risk factors for IUGR are easy to assess but have poor predictive value. For the diagnostic purpose, biochemical serum markers, ultrasound and Doppler study of uterine and spiral arteries, placental volume and vascularization, first trimester growth pattern are object of assessment today. Modern evaluations propose combined algorithms using these strategies, all with the goal of a better prediction of risk pregnancies. Abbreviations: SGA = small for gestational age; IUGR = intrauterine growth restriction; FGR = fetal growth restriction; IUFD = intrauterine fetal demise; HIV = human immunodeficiency virus; PAPP-A = pregnancy associated plasmatic protein A; β-hCG = beta human chorionic gonadotropin; MoM = multiple of median; ADAM-12 = A-disintegrin and metalloprotease 12; PP-13 = placental protein 13; VEGF = vascular endothelial growth factor; PlGF = placental growth factor; sFlt-1 = soluble fms-like tyrosine kinase-1; UAD = uterine arteries Doppler ultrasound; RI = resistence index; PI = pulsatility index; VOCAL = Virtual Organ Computer–Aided Analysis software; VI = vascularization index; FI = flow index; VFI = vascularization flow index; PQ = placental quotient PMID:25408721

  5. Growth factors and growth factor receptors in the hippocampus. Role in plasticity and response to injury.

    PubMed

    Nieto-Sampedro, M; Bovolenta, P

    1990-01-01

    Various growth factors are present in the hippocampal formation and appear responsible for the prominent plasticity of this brain area. Although hormone-like growth-promoting polypeptides are the best known, recent studies emphasize the importance in the growth response of molecules such as laminin proteoglycans, neurotransmitters and growth inhibitors. The progress and problems in the study of these substances are reviewed.

  6. Bradykinin-induced growth inhibition of normal rat kidney (NRK) cells is paralleled by a decrease in epidermal-growth-factor receptor expression.

    PubMed Central

    Van Zoelen, E J; Peters, P H; Afink, G B; Van Genesen, S; De Roos, D G; Van Rotterdam, W; Theuvenet, A P

    1994-01-01

    Normal rat kidney fibroblasts, grown to density arrest in the presence of epidermal growth factor (EGF), can be induced to undergo phenotypic transformation by treatment with transforming growth factor beta or retinoic acid. Here we show that bradykinin blocks this growth-stimulus-induced loss of density-dependent growth arrest by a specific receptor-mediated mechanism. The effects of bradykinin are specific, and are not mimicked by other phosphoinositide-mobilizing agents such as prostaglandin F2 alpha. Northern-blot analysis and receptor-binding studies demonstrate that bradykinin also inhibits the retinoic acid-induced increase in EGF receptor levels in these cells. These studies provide additional evidence that EGF receptor levels modulate EGF-induced expression of the transformed phenotype in these cells. Images Figure 5 PMID:8135739

  7. Hepatocyte growth factor/scatter factor-MET signaling in neural crest-derived melanocyte development.

    PubMed

    Kos, L; Aronzon, A; Takayama, H; Maina, F; Ponzetto, C; Merlino, G; Pavan, W

    1999-02-01

    The mechanisms governing development of neural crest-derived melanocytes, and how alterations in these pathways lead to hypopigmentation disorders, are not completely understood. Hepatocyte growth factor/scatter factor (HGF/SF) signaling through the tyrosine-kinase receptor, MET, is capable of promoting the proliferation, increasing the motility, and maintaining high tyrosinase activity and melanin synthesis of melanocytes in vitro. In addition, transgenic mice that ubiquitously overexpress HGF/SF demonstrate hyperpigmentation in the skin and leptomenigenes and develop melanomas. To investigate whether HGF/ SF-MET signaling is involved in the development of neural crest-derived melanocytes, transgenic embryos, ubiquitously overexpressing HGF/SF, were analyzed. In HGF/SF transgenic embryos, the distribution of melanoblasts along the characteristic migratory pathway was not affected. However, additional ectopically localized melanoblasts were also observed in the dorsal root ganglia and neural tube, as early as 11.5 days post coitus (p.c.). We utilized an in vitro neural crest culture assay to further explore the role of HGF/SF-MET signaling in neural crest development. HGF/SF added to neural crest cultures increased melanoblast number, permitted differentiation into pigmented melanocytes, promoted melanoblast survival, and could replace mast-cell growth factor/Steel factor (MGF) in explant cultures. To examine whether HGF/SF-MET signaling is required for the proper development of melanocytes, embryos with a targeted Met null mutation (Met-/-) were analysed. In Met-/- embryos, melanoblast number and location were not overtly affected up to 14 days p.c. These results demonstrate that HGF/SF-MET signaling influences, but is not required for, the initial development of neural crest-derived melanocytes in vivo and in vitro.

  8. Engineering growth factors for regenerative medicine applications.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mitchell, Aaron C.; Briquez, Priscilla S.; Hubbell, Jeffrey A.

    Growth factors are important morphogenetic proteins that instruct cell behavior and guide tissue repair and renewal. Although their therapeutic potential holds great promise in regenerative medicine applications, translation of growth factors into clinical treatments has been hindered by limitations including poor protein stability, low recombinant expression yield, and suboptimal efficacy. This review highlights current tools, technologies, and approaches to design integrated and effective growth factor-based therapies for regenerative medicine applications. The first section describes rational and combinatorial protein engineering approaches that have been utilized to improve growth factor stability, expression yield, biodistribution, and serum half-life, or alter their cell traffickingmore » behavior or receptor binding affinity. The second section highlights elegant biomaterial-based systems, inspired by the natural extracellular matrix milieu, that have been developed for effective spatial and temporal delivery of growth factors to cell surface receptors. Although appearing distinct, these two approaches are highly complementary and involve principles of molecular design and engineering to be considered in parallel when developing optimal materials for clinical applications.« less

  9. Fibroblast growth factors: key players in regeneration and tissue repair.

    PubMed

    Maddaluno, Luigi; Urwyler, Corinne; Werner, Sabine

    2017-11-15

    Tissue injury initiates a complex repair process, which in some organisms can lead to the complete regeneration of a tissue. In mammals, however, the repair of most organs is imperfect and results in scar formation. Both regeneration and repair are orchestrated by a highly coordinated interplay of different growth factors and cytokines. Among the key players are the fibroblast growth factors (FGFs), which control the migration, proliferation, differentiation and survival of different cell types. In addition, FGFs influence the expression of other factors involved in the regenerative response. Here, we summarize current knowledge on the roles of endogenous FGFs in regeneration and repair in different organisms and in different tissues and organs. Gaining a better understanding of these FGF activities is important for appropriate modulation of FGF signaling after injury to prevent impaired healing and to promote organ regeneration in humans. © 2017. Published by The Company of Biologists Ltd.

  10. Effects of heparin-binding epidermal growth factor-like growth factor on cell repopulation and signal transduction in periodontal ligament cells after scratch wounding in vitro.

    PubMed

    Lee, J S; Kim, J M; Hong, E K; Kim, S-O; Yoo, Y-J; Cha, J-H

    2009-02-01

    A growing amount of attention has been placed on periodontal regeneration and wound healing for periodontal therapy. This study was conducted in an effort to determine the effects of heparin-binding epidermal growth factor-like growth factor on cell repopulation and signal transduction in periodontal ligament cells after scratch wounding in vitro. Human periodontal ligament cells were acquired from explant tissue of human healthy periodontal ligament. After the wounding of periodontal ligament cells, the change in expression of heparin-binding epidermal growth factor-like growth factor and epidermal growth factor receptors 1-4 mRNA was assessed. The effects of heparin-binding epidermal growth factor-like growth factor on periodontal ligament cell proliferation and repopulation were assessed in vitro via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and by photographing the injuries, respectively. Extracellular signal-regulated kinase (Erk)1/2, p38 and Akt phosphorylation was characterized via western blotting. Scratch wounding resulted in a significant up-regulation of heparin-binding epidermal growth factor-like growth factor mRNA expression, whereas wounding had no effect on the expression levels of epidermal growth factor receptors 1-4. Interestingly, no expression of epidermal growth factor receptors 2 and 4 was detectable prior to or after wounding. Heparin-binding epidermal growth factor-like growth factor treatment promoted the proliferation and repopulation of periodontal ligament cells. The scratch wounding also stimulated the phosphorylation of Erk1/2 and p38, but not of Akt, in periodontal ligament cells, and heparin-binding epidermal growth factor-like growth factor treatment applied after wounding amplified and extended the activations of Erk1/2 and p38, but not of Akt. Furthermore, Erk1/2 inhibition blocked the process of cell repopulation induced by heparin-binding epidermal growth factor-like growth factor, whereas the

  11. Growth factor involvement in tension-induced skeletal muscle growth

    NASA Technical Reports Server (NTRS)

    Vandenburgh, H. H.

    1987-01-01

    Muscle tissue culture techniques were developed to grow skeletal myofibers which differentiate into more adult-like myofibers. Mechanical simulation studies of these muscle cells in a newly developed mechanical cell simulator can now be performed to study growth processes in skeletal muscle. Conditions in the mechanical cell simulator were defined where mechanical activity can either prevent muscle wasting or stimulate muscle growth. The role of endogenous and exogenous growth factors in tension-induced muscle growth is being investigated under the defined conditions of tissue culture.

  12. Inhibition of vascular endothelial growth factor-induced angiogenesis suppresses tumour growth in vivo

    NASA Astrophysics Data System (ADS)

    Kim, K. Jin; Li, Bing; Winer, Jane; Armanini, Mark; Gillett, Nancy; Phillips, Heidi S.; Ferrara, Napoleone

    1993-04-01

    THE development of new blood vessels (angiogenesis) is required for many physiological processes including embryogenesis, wound healing and corpus luteum formation1,2. Blood vessel neoformation is also important in the pathogenesis of many disorders1-5, particularly rapid growth and metastasis of solid tumours3-5. There are several potential mediators of tumour angiogenesis, including basic and acidic fibroblast growth factors, tumour necrosis factor-α and transforming factors-α and -β 1,2. But it is unclear whether any of these agents actually mediates angiogenesis and tumour growth in vivo. Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen and an angiogenesis inducer released by a variety of tumour cells and expressed in human tumours in situ. To test whether VEGF may be a tumour angiogenesis factor in vivo, we injected human rhabdomyosar-coma, glioblastoma multiforme or leiomyosarcoma cell lines into nude mice. We report here that treatment with a monoclonal antibody specific for VEGF inhibited the growth of the tumours, but had no effect on the growth rate of the tumour cells In vitro. The density of vessels was decreased in the antibody-treated tumours. These findings demonstrate that inhibition of the action of an angiogenic factor spontaneously produced by tumour cells may suppress tumour growth in vivo.

  13. Fibroblast growth factor receptor inhibitors.

    PubMed

    Kumar, Suneel B V S; Narasu, Lakshmi; Gundla, Rambabu; Dayam, Raveendra; J A R P, Sarma

    2013-01-01

    Fibroblast growth factor receptors (FGFRs) play an important role in embryonic development, angiogenesis, wound healing, cell proliferation and differentiation. The fibroblast growth factor receptor (FGFR) isoforms have been under intense scrutiny for effective anticancer drug candidates. The fibroblast growth factor (FGF) and its receptor (FGFR) provide another pathway that seems critical to monitoring angiogenesis. Recent findings suggest that FGFR mediates signaling, regulates the PKM2 activity, and plays a crucial role in cancer metabolism. The current review also covers the recent findings on the role of FGFR1 in cancer metabolism. This paper reviews the progress, mechanism, and binding modes of recently known kinase inhibitors such as PD173074, SU series and other inhibitors still under clinical development. Some of the structural classes that will be highlighted in this review include Pyrido[2,3-d]pyrimidines, Indolin- 2-one, Pyrrolo[2,1-f][1,2,4]triazine, Pyrido[2,3-d]pyrimidin-7(8H)-one, and 1,6- Naphthyridin-2(1H)-ones.

  14. The effect of growth factors on both collagen synthesis and tensile strength of engineered human ligaments.

    PubMed

    Hagerty, Paul; Lee, Ann; Calve, Sarah; Lee, Cassandra A; Vidal, Martin; Baar, Keith

    2012-09-01

    Growth factors play a central role in the development and remodelling of musculoskeletal tissues. To determine which growth factors optimized in vitro ligament formation and mechanics, a Box-Behnken designed array of varying concentrations of growth factors and ascorbic acid were applied to engineered ligaments and the collagen content and mechanics of the grafts were determined. Increasing the amount of transforming growth factor (TGF) β1 and insulin-like growth factor (IGF)-1 led to an additive effect on ligament collagen and maximal tensile load (MTL). In contrast, epidermal growth factor (EGF) had a negative effect on both collagen content and MTL. The predicted optimal growth media (50 μg/ml TGFβ, IGF-1, and GDF-7 and 200 μM ascorbic acid) was then validated in two separate trials: showing a 5.7-fold greater MTL and 5.2-fold more collagen than a minimal media. Notably, the effect of the maximized growth media was scalable such that larger constructs developed the same material properties, but larger MTL. These results show that optimizing the interactions between growth factors and engineered ligament volume results in an engineered ligament of clinically relevant function. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Expression of a transmembrane phosphotyrosine phosphatase inhibits cellular response to platelet-derived growth factor and insulin-like growth factor-1.

    PubMed

    Mooney, R A; Freund, G G; Way, B A; Bordwell, K L

    1992-11-25

    Tyrosine phosphorylation is a mechanism of signal transduction shared by many growth factor receptors and oncogene products. Phosphotyrosine phosphatases (PTPases) potentially modulate or counter-regulate these signaling pathways. To test this hypothesis, the transmembrane PTPase CD45 (leukocyte common antigen) was expressed in the murine cell line C127. Hormone-dependent autophosphorylation of the platelet-derived growth factor (PDGF) and insulin-like growth factor-1 (IGF-1) receptors was markedly reduced in cells expressing the transmembrane PTPase. Tyrosine phosphorylation of other PDGF-dependent phosphoproteins (160, 140, and 55 kDa) and IGF-1-dependent phosphoproteins (145 kDa) was similarly decreased. Interestingly, the pattern of growth factor-independent tyrosine phosphorylations was comparable in cells expressing the PTPase and control cells. This suggests a selectivity or accessibility of the PTPase limited to a subset of cellular phosphotyrosyl proteins. The maximum mitogenic response to PDGF and IGF-1 in cells expressing the PTPase was decreased by 67 and 71%, respectively. These results demonstrate that a transmembrane PTPase can both affect the tyrosine phosphorylation state of growth factor receptors and modulate proximal and distal cellular responses to the growth factors.

  16. Cross-talk between GPER and growth factor signaling.

    PubMed

    Lappano, Rosamaria; De Marco, Paola; De Francesco, Ernestina Marianna; Chimento, Adele; Pezzi, Vincenzo; Maggiolini, Marcello

    2013-09-01

    G protein-coupled receptors (GPCRs) and growth factor receptors mediate multiple physio-pathological responses to a diverse array of extracellular stimuli. In this regard, it has been largely demonstrated that GPCRs and growth factor receptors generate a multifaceted signaling network, which triggers relevant biological effects in normal and cancer cells. For instance, some GPCRs transactivate the epidermal growth factor receptor (EGFR), which stimulates diverse transduction pathways leading to gene expression changes, cell migration, survival and proliferation. Moreover, it has been reported that a functional interaction between growth factor receptors and steroid hormones like estrogens is involved in the growth of many types of tumors as well as in the resistance to endocrine therapy. This review highlights recent findings on the cross-talk between a member of the GPCR family, the G protein-coupled estrogen receptor 1 (GPER, formerly known as GPR30) and two main growth factor receptors like EGFR and insulin-like growth factor-I receptor (IGF-IR). The biological implications of the functional interaction between these important mediators of cell responses particularly in cancer are discussed. This article is part of a Special Issue entitled 'CSR 2013'. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Time dependent impact of perinatal hypoxia on growth hormone, insulin-like growth factor 1 and insulin-like growth factor binding protein-3.

    PubMed

    Kartal, Ömer; Aydınöz, Seçil; Kartal, Ayşe Tuğba; Kelestemur, Taha; Caglayan, Ahmet Burak; Beker, Mustafa Caglar; Karademir, Ferhan; Süleymanoğlu, Selami; Kul, Mustafa; Yulug, Burak; Kilic, Ertugrul

    2016-08-01

    Hypoxic-ischemia (HI) is a widely used animal model to mimic the preterm or perinatal sublethal hypoxia, including hypoxic-ischemic encephalopathy. It causes diffuse neurodegeneration in the brain and results in mental retardation, hyperactivity, cerebral palsy, epilepsy and neuroendocrine disturbances. Herein, we examined acute and subacute correlations between neuronal degeneration and serum growth factor changes, including growth hormone (GH), insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) after hypoxic-ischemia (HI) in neonatal rats. In the acute phase of hypoxia, brain volume was increased significantly as compared with control animals, which was associated with reduced GH and IGF-1 secretions. Reduced neuronal survival and increased DNA fragmentation were also noticed in these animals. However, in the subacute phase of hypoxia, neuronal survival and brain volume were significantly decreased, accompanied by increased apoptotic cell death in the hippocampus and cortex. Serum GH, IGF-1, and IGFBP-3 levels were significantly reduced in the subacute phase of HI. Significant retardation in the brain and body development were noted in the subacute phase of hypoxia. Here, we provide evidence that serum levels of growth-hormone and factors were decreased in the acute and subacute phase of hypoxia, which was associated with increased DNA fragmentation and decreased neuronal survival.

  18. Uncovering molecular details of urea crystal growth in the presence of additives.

    PubMed

    Salvalaglio, Matteo; Vetter, Thomas; Giberti, Federico; Mazzotti, Marco; Parrinello, Michele

    2012-10-17

    Controlling the shape of crystals is of great practical relevance in fields like pharmacology and fine chemistry. Here we examine the paradigmatic case of urea which is known to crystallize from water with a needle-like morphology. To prevent this undesired effect, inhibitors that selectively favor or discourage the growth of specific crystal faces can be used. In urea the most relevant faces are the {001} and the {110} which are known to grow fast and slow, respectively. The relevant growth speed difference between these two crystal faces is responsible for the needle-like structure of crystals grown in water solution. To prevent this effect, additives are used to slow down the growth of one face relative to another, thus controlling the shape of the crystal. We study the growth of fast {001} and slow {110} faces in water solution and the effect of shape controlling inhibitors like biuret. Extensive sampling through molecular dynamics simulations provides a microscopic picture of the growth mechanism and of the role of the additives. We find a continuous growth mechanism on the {001} face, while the slow growing {110} face evolves through a birth and spread process, in which the rate-determining step is the formation on the surface of a two-dimensional crystalline nucleus. On the {001} face, growth inhibitors like biuret compete with urea for the adsorption on surface lattice sites; on the {110} face instead additives cannot interact specifically with surface sites and play a marginal sterical hindrance of the crystal growth. The free energies of adsorption of additives and urea are evaluated with advanced simulation methods (well-tempered metadynamics) allowing a microscopic understanding of the selective effect of additives. Based on this case study, general principles for the understanding of the anisotropic growth of molecular crystals from solutions are laid out. Our work is a step toward a rational development of novel shape-affecting additives.

  19. RAPID COMMUNICATION: Nerve growth factor influences cleavage rate and embryo development in sheep.

    PubMed

    Crispo, M; Dos Santos-Neto, P C; Vilariño, M; Mulet, A P; de León, A; Barbeito, L; Menchaca, A

    2016-10-01

    Recent information about Nerve growth factor (NGF), a protein traditionally associated to the nervous system that regulates survival and maturation of developing neurons, suggests that it may exert action also on different levels in the reproductive system. The aim of this study was to evaluate the effect of NGF added during in vitro oocyte maturation, fertilization or in vitro embryo development in sheep. Nerve growth factor was supplemented to the culture medium at 0, 100, or 1,000 ng/mL, during either in vitro maturation (Exp. 1), in vitro fertilization (Exp. 2), or in vitro culture (Exp. 3). In addition, NGF mRNA expression was determined in cumulus cells and oocytes. Nerve growth factor induced early cleavage when added during oocyte maturation or fertilization, improved embryo development when added during fertilization, and had no significant effect when added during embryo culture. In general, the effect was more evident with 100 rather than 1,000 ng/mL (P < 0.05). Expression of endogenous NGF was not detected in oocytes, and increased in cumulus cells when 1,000 ng/mL of NGF was added during fertilization, but not during maturation and embryo culture. In conclusion, the addition of NGF during oocyte maturation and fertilization affects in vitro cleavage and embryo development in sheep. We suggest a possible effect of this growth factor on oocyte maturation and mainly on the fertilization process.

  20. Novel targeted approaches to treating biliary tract cancer: the dual epidermal growth factor receptor and ErbB-2 tyrosine kinase inhibitor NVP-AEE788 is more efficient than the epidermal growth factor receptor inhibitors gefitinib and erlotinib.

    PubMed

    Wiedmann, Marcus; Feisthammel, Jürgen; Blüthner, Thilo; Tannapfel, Andrea; Kamenz, Thomas; Kluge, Annett; Mössner, Joachim; Caca, Karel

    2006-08-01

    Aberrant activation of the epidermal growth factor receptor is frequently observed in neoplasia, notably in tumors of epithelial origin. Attempts to treat such tumors with epidermal growth factor receptor antagonists resulted in remarkable success in recent studies. Little is known, however, about the efficacy of this therapy in biliary tract cancer. Protein expression of epidermal growth factor receptor, ErbB-2, and vascular endothelial growth factor receptor-2 was assessed in seven human biliary tract cancer cell lines by immunoblotting. In addition, histological sections from 19 patients with extrahepatic cholangiocarcinoma were analyzed for epidermal growth factor receptor, ErbB-2 and vascular endothelial growth factor receptor-2 expression by immunohistochemistry. Moreover, we sequenced the cDNA products representing the entire epidermal growth factor receptor coding region of the seven cell lines, and searched for genomic epidermal growth factor receptor amplifications and polysomy by fluorescence in-situ hybridization. Cell growth inhibition by gefitinib erlotinib and NVP-AEE788 was studied in vitro by automated cell counting. In addition, the anti-tumoral effect of erlotinib and NVP-AEE788 was studied in a chimeric mouse model. The anti-tumoral drug mechanism in this model was assessed by MIB-1 antibody staining, terminal deoxynucleotidyl transfer-mediated dUTP nick end-labelling assay, von Willebrand factor staining, and immunoblotting for p-p42/44 (p-Erk1/2, p-MAPK) and p-AKT. Immunoblotting revealed expression of epidermal growth factor receptor, ErbB-2, and vascular endothelial growth factor receptor-2 in all biliary tract cancer cell lines. EGFR was detectable in six of 19 (32%) extrahepatic human cholangiocarcinoma tissue samples, ErbB-2 in 16 of 19 (84%), and vascular endothelial growth factor receptor-2 in nine of 19 (47%). Neither epidermal growth factor receptor mutations nor amplifications or polysomy were found in the seven biliary tract cancer

  1. Targeted delivery of growth factors in ischemic stroke animal models.

    PubMed

    Rhim, Taiyoun; Lee, Minhyung

    2016-01-01

    Ischemic stroke is caused by reduced blood supply and leads to loss of brain function. The reduced oxygen and nutrient supply stimulates various physiological responses, including induction of growth factors. Growth factors prevent neuronal cell death, promote neovascularization, and induce cell growth. However, the concentration of growth factors is not sufficient to recover brain function after the ischemic damage, suggesting that delivery of growth factors into the ischemic brain may be a useful treatment for ischemic stroke. In this review, various approaches for the delivery of growth factors to ischemic brain tissue are discussed, including local and targeting delivery systems. To develop growth factor therapy for ischemic stroke, important considerations should be taken into account. First, growth factors may have possible side effects. Thus, concentration of growth factors should be restricted to the ischemic tissues by local administration or targeted delivery. Second, the duration of growth factor therapy should be optimized. Growth factor proteins may be degraded too fast to have a high enough therapeutic effect. Therefore, delivery systems for controlled release or gene delivery may be useful. Third, the delivery systems to the brain should be optimized according to the delivery route.

  2. Insulin-like growth factor I gene deletion causing intrauterine growth retardation and severe short stature.

    PubMed

    Woods, K A; Camacho-Hübner, C; Barter, D; Clark, A J; Savage, M O

    1997-11-01

    The first human case of a homozygous molecular defect in the gene encoding insulin-like growth factor I (IGF-I) is described. The patient was a 15-year-old boy from a consanguineous pedigree who presented with severe intrauterine growth failure, sensorineural deafness and mild mental retardation. Endocrine evaluation of the growth hormone (GH)--IGF-I axis revealed elevated GH secretion, undetectable serum IGF-I and normal serum IGF-binding protein-3, acid-labile subunit, and GH-binding activity. Analysis of the IGF-I gene revealed a homozygous partial IGF-I gene deletion involving exons 4 and 5, which encodes a severely truncated mature IGF-I peptide. This patient demonstrates that complete disruption of the IGF-I gene in man is compatible with life, and indicates a major role for IGF-I in human fetal growth. In addition, his neurological abnormalities suggest that IGF-I may be involved in central nervous system development.

  3. Down-regulation of connective tissue growth factor by inhibition of transforming growth factor beta blocks the tumor-stroma cross-talk and tumor progression in hepatocellular carcinoma.

    PubMed

    Mazzocca, Antonio; Fransvea, Emilia; Dituri, Francesco; Lupo, Luigi; Antonaci, Salvatore; Giannelli, Gianluigi

    2010-02-01

    Tumor-stroma interactions in hepatocellular carcinoma (HCC) are of key importance to tumor progression. In this study, we show that HCC invasive cells produce high levels of connective tissue growth factor (CTGF) and generate tumors with a high stromal component in a xenograft model. A transforming growth factor beta (TGF-beta) receptor inhibitor, LY2109761, inhibited the synthesis and release of CTGF, as well as reducing the stromal component of the tumors. In addition, the TGF-beta-dependent down-regulation of CTGF diminished tumor growth, intravasation, and metastatic dissemination of HCC cells by inhibiting cancer-associated fibroblast proliferation. By contrast, noninvasive HCC cells were found to produce low levels of CTGF. Upon TGF-beta1 stimulation, noninvasive HCC cells form tumors with a high stromal content and CTGF expression, which is inhibited by treatment with LY2109761. In addition, the acquired intravasation and metastatic spread of noninvasive HCC cells after TGF-beta1 stimulation was blocked by LY2109761. LY2109761 interrupts the cross-talk between cancer cells and cancer-associated fibroblasts, leading to a significant reduction of HCC growth and dissemination. Interestingly, patients with high CTGF expression had poor prognosis, suggesting that treatment aimed at reducing TGF-beta-dependent CTGF expression may offer clinical benefits. Taken together, our preclinical results indicate that LY2109761 targets the cross-talk between HCC and the stroma and provide a rationale for future clinical trials.

  4. Role of growth hormone, insulin-like growth factor-I, and insulin-like growth factor binding proteins in the catabolic response to injury and infection.

    PubMed

    Lang, Charles H; Frost, Robert A

    2002-05-01

    The erosion of lean body mass resulting from protracted critical illness remains a significant risk factor for increased morbidity and mortality in this patient population. Previous studies have documented the well known impairment in nitrogen balance results from both an increase in muscle protein degradation as well as a decreased rate of both myofibrillar and sacroplasmic protein synthesis. This protein imbalance may be caused by an increased presence or activity of various catabolic agents, such as tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6 or glucocorticoids, or may be mediated via a decreased concentration or responsiveness to various anabolic hormones, such as growth hormone or insulin-like growth factor-I. This review focuses on recent developments pertaining to the importance of alterations in the growth hormone-insulin-like growth factor-I axis as a mechanism for the observed defects in muscle protein balance.

  5. Effect of carbide additions on grain growth in TiC-Ni cermets

    NASA Astrophysics Data System (ADS)

    Shin, Soon-Gi; Lee, Jun-Hee

    2006-02-01

    The growth of carbide particles in TiC-XC-2 vol.% Ni and TiC-XC-30 vol.% Ni alloys, where X=Zr, Cr, W, Ta and Mo, was fitted to an equation of the form d3-do 3=Kt. The grain growth behavior during liquid phase sintering at 1673K decreased markedly with the addition of Mo2C or WC, changed little for TaC, and increased with the addition of ZrC or Cr3C2. The grain contiguity decreased with increasing Ni content in the TiC-Mo2C-Ni alloy and was greater in the alloys with smaller growth rate constant. Consequently, the effect of carbide addition on the grain growth of 2 vol.% Ni alloys was found to be similar to that of 30 vol.% Ni alloys. The grain growth mechanism could be explained by the effect of contiguous carbide grain boundaries in restricting the overall grain growth, as well as the area of the solid/liquid interfaces in the alloy by the usual solution/reprecipitation model.

  6. Constructing a blood vessel on the porous scaffold modified with vascular endothelial growth factor and basic fibroblast growth factor

    NASA Astrophysics Data System (ADS)

    Sevostyanova, V. V.; Matveeva, V. G.; Antonova, L. V.; Velikanova, E. A.; Shabaev, A. R.; Senokosova, E. A.; Krivkina, E. O.; Vasyukov, G. Yu.; Glushkova, T. V.; Kudryavtseva, Yu. A.; Barbarash, O. L.; Barbarash, L. S.

    2016-11-01

    Incorporation of the growth factors into biodegradable polymers is a promising approach for the fabrication of tissue-engineered vascular grafts. Here we blended poly(ɛ-caprolactone) (PCL) with poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) following incorporation of either vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) and then fabricated electrospun 2 mm diameter vascular grafts. Grafts without the growth factors were used as a control group. Structure of the grafts was assessed utilizing scanning electron microscopy. We further implanted our grafts into rat abdominal aorta for 1 and 3 months with the aim to test endothelialization, cell infiltration, and patency in vivo. Histological and immunofluorescence examination demonstrated enhanced endothelialization and cell infiltration of the grafts with either VEGF or bFGF compared to those without the growth factors. Grafts with VEGF showed higher patency compared to those with bFGF; however, bFGF promoted migration of smooth muscle cells and fibroblasts into the graft. Therefore, we conclude that incorporation of VEGF and bFGF into the inner and medial/outer layer, respectively, can be a promising option for the fabrication of tissue-engineered vascular grafts.

  7. Conditioned media from a renal cell carcinoma cell line demonstrates the presence of basic fibroblast growth factor.

    PubMed

    Mydlo, J H; Zajac, J; Macchia, R J

    1993-09-01

    In a previous report, we demonstrated the isolation and purification of a heparin binding growth factor from human renal carcinoma, and suggested that this growth factor may play a role in the neovascularity and growth of the tumor. In this report, we demonstrate that the growth of the renal cell carcinoma cell line RC29 is stimulated by the addition of exogenous fibroblast growth factor (FGF), epidermal growth factor (EGF) and transforming growth factor alpha (TGF alpha). Also, media conditioned by this cell line was able to stimulate growth of the A431 vulvar tumor cell line, known for its high concentration of EGF receptors, 3T3 fibroblasts, human umbilical vein (HUV) cells and RC29 cells. Using heparin-sepharose chromatography and then SDS polyacrylamide gel electrophoresis (PAGE), we were able to demonstrate several proteins in the conditioned media of the RC29 cell line. Using Western blot analysis, we detected that at least one of the proteins expressed in this conditioned media was FGF and that it belongs to the basic, not acidic, family of fibroblast growth factors. These findings suggest that renal tumors may express growth factors that may play a direct role in maintaining their unrestricted proliferation.

  8. Basic Fibroblast Growth Factor Influences Epidermal Homeostasis of Living Skin Equivalents through Affecting Fibroblast Phenotypes and Functions.

    PubMed

    Yang, Lujun; Zhang, Dangui; Wu, Hongjuan; Xie, Sitian; Zhang, Mingjun; Zhang, Bingna; Tang, Shijie

    2018-05-30

    To elucidate the possible mechanisms of how basic fibroblast growth factor (bFGF) influences epidermal homeostasis in a living skin equivalent (LSE) model. Several wound healing-related growth factors were analyzed at protein and mRNA levels for dermal fibroblasts of induced alpha-smooth muscle actin (α-SMA)-positive or α-SMA-negative phenotypes. During culturing an LSE model by seeding normal human keratinocytes on a fibroblast-populated type I collagen gel, bFGF or neutralizing antibody for keratinocyte growth factor (KGF) was added to investigate its effects on fibroblast phenotypes and, subsequently, epidermal homeostasis by histology and immunohistochemistry. The α-SMA-positive phenotype of fibroblasts induced by transforming growth factor beta-1 (TGF-β1) markedly suppressed the expression of KGF and hepatocyte growth factor (HGF), and slightly upregulated vascular endothelial growth factor (VEGF) and TGF-β1 at mRNA and protein levels, compared with α-SMA-negative fibroblasts treated with bFGF. α-SMA expression of fibroblasts at the epidermal-mesenchymal junction of the LSEs was suppressed by the addition of bFGF, and a better-differentiated epidermis was presented. The abrogation of KGF from fibroblasts by the addition of the KGF neutralizing antibody disenabled the LSE culturing system to develop an epidermis. bFGF, through affecting the phenotypes and functions of fibroblasts, especially KGF expression, influenced epidermal homeostasis in an LSE model. © 2018 S. Karger AG, Basel.

  9. Kisspeptin regulates the somatic growth-related factors of the cinnamon clownfish Amphiprion melanopus.

    PubMed

    Kim, Na Na; Choi, Young-Ung; Park, Heung-Sik; Choi, Cheol Young

    2015-01-01

    This study aimed to test the effects of kisspeptin (Kiss) on somatic growth in the cinnamon clownfish Amphiprion melanopus. We investigated the effects of Kiss treatment on the growth by measuring the mRNA expressions of the growth hormone (GH), insulin-like growth hormone factor (IGF-I), somatolactin (SL), and melatonin receptor (MT). The expression levels of GH and SL of the pituitary gland and IGF-I of the liver increased after Kiss treatment (in vivo and in vitro). In addition, the MT mRNA expression increased in the pituitary gland and brain after Kiss treatment (in vivo and in vitro). These results support the hypothesis that Kiss directly regulates the somatic growth-related factors, such as GH, SL, and MT, and IGF-I in the cinnamon clownfish. Further, injection of Kiss resulted in significantly higher levels of plasma melatonin than that in the control. We, therefore, conclude that Kiss plays a role in modulating growth and artificially induced rapid growth in cinnamon clownfish. Copyright © 2014 Elsevier Inc. All rights reserved.

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

    DTIC Science & Technology

    1998-05-01

    I., Polyak, K., Iavarone, A., and Massagud, J. Kip/ Cip and Ink4 cdk inhibitors cooperate to induce cell cycle arrest in response to TGF-ß. Genes Dev...specimens. Thirdly, we have developped transient transfection assays to determine how specific TßR mutations affect affect receptor function. Using...Growth Factor-ß (TGFß) is the most potent known inhibitor of cell cycle progression of normal mammary epithelial cells; in addition, it causes cells

  11. 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 ...

  12. Fibroblast Growth Factor 2: An Epithelial Ductal Cell Growth Inhibitor That Drops Out in Breast Cancer

    DTIC Science & Technology

    2009-10-01

    AD_________________ Award Number: W81XWH-08-1-0708 TITLE: Fibroblast Growth Factor 2: an...September 2008 – 14 September 2009 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Fibroblast Growth Factor 2: an Epithelial Ductal Cell Growth Inhibitor...9 Fibroblast Growth Factor -2: an Epithelial Ductal Cell Growth Inhibitor that Drops Out in Breast Cancer

  13. Region-specific role of growth differentiation factor-5 in the establishment of sympathetic innervation.

    PubMed

    O'Keeffe, Gerard W; Gutierrez, Humberto; Howard, Laura; Laurie, Christopher W; Osorio, Catarina; Gavaldà, Núria; Wyatt, Sean L; Davies, Alun M

    2016-02-15

    Nerve growth factor (NGF) is the prototypical target-derived neurotrophic factor required for sympathetic neuron survival and for the growth and ramification of sympathetic axons within most but not all sympathetic targets. This implies the operation of additional target-derived factors for regulating terminal sympathetic axon growth and branching. Here report that growth differentiation factor 5 (GDF5), a widely expressed member of the transforming growth factor beta (TGFβ) superfamily required for limb development, promoted axon growth from mouse superior cervical ganglion (SCG) neurons independently of NGF and enhanced axon growth in combination with NGF. GDF5 had no effect on neuronal survival and influenced axon growth during a narrow window of postnatal development when sympathetic axons are ramifying extensively in their targets in vivo. SCG neurons expressed all receptors capable of participating in GDF5 signaling at this stage of development. Using compartment cultures, we demonstrated that GDF5 exerted its growth promoting effect by acting directly on axons and by initiating retrograde canonical Smad signalling to the nucleus. GDF5 is synthesized in sympathetic targets, and examination of several anatomically circumscribed tissues in Gdf5 null mice revealed regional deficits in sympathetic innervation. There was a marked, highly significant reduction in the sympathetic innervation density of the iris, a smaller though significant reduction in the trachea, but no reduction in the submandibular salivary gland. There was no reduction in the number of neurons in the SCG. These findings show that GDF5 is a novel target-derived factor that promotes sympathetic axon growth and branching and makes a distinctive regional contribution to the establishment of sympathetic innervation, but unlike NGF, plays no role in regulating sympathetic neuron survival.

  14. Epidermal growth factor receptor in non-small cell lung cancer

    PubMed Central

    2015-01-01

    Following the identification of a group of patients in the initial tyrosine kinase inhibitor (TKI) trials for lung cancer, there has been detailed focus on which patients may benefit from inhibitor therapy. This article reviews the background, genetics and prevalence of epidermal growth factor mutations in non-small cell lung cancer (NSCLC). Additionally, the prevalence in unselected patients is compared against various other reviews. PMID:25870793

  15. Endogenous versus Exogenous Growth Factor Regulation of Articular Chondrocytes

    PubMed Central

    Shi, Shuiliang; Chan, Albert G.; Mercer, Scott; Eckert, George J.; Trippel, Stephen B.

    2014-01-01

    Anabolic growth factors that regulate the function of articular chondrocytes are candidates for articular cartilage repair. Such factors may be delivered by pharmacotherapy in the form of exogenous proteins, or by gene therapy as endogenous proteins. It is unknown whether delivery method influences growth factor effectiveness in regulating articular chondrocyte reparative functions. We treated adult bovine articular chondrocytes with exogenous recombinant insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-β1), or with the genes encoding these growth factors for endogenous production. Treatment effects were measured as change in chondrocyte DNA content, glycosaminoglycan production, and aggrecan gene expression. We found that IGF-I stimulated chondrocyte biosynthesis similarly when delivered by either exogenous or endogenous means. In contrast, exogenous TGF-ß1 stimulated these reparative functions, while endogenous TGF-ß1 had little effect. Endogenous TGF-ß1 became more bioactive following activation of the transgene protein product. These data indicate that effective mechanisms of growth factor delivery for articular cartilage repair may differ for different growth factors. In the case of IGF-I, gene therapy or protein therapy appear to be viable options. In contrast, TGF-ß1 gene therapy may be constrained by a limited ability of chondrocytes to convert latent complexes to an active form. PMID:24105960

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sieweke, M.H.; Bissell, M.J.; Thompson, N.L.

    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 ledmore » 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.« less

  17. Fibroblast Growth Factors and Vascular Endothelial Growth Factor Promote Cardiac Reprogramming under Defined Conditions

    PubMed Central

    Yamakawa, Hiroyuki; Muraoka, Naoto; Miyamoto, Kazutaka; Sadahiro, Taketaro; Isomi, Mari; Haginiwa, Sho; Kojima, Hidenori; Umei, Tomohiko; Akiyama, Mizuha; Kuishi, Yuki; Kurokawa, Junko; Furukawa, Tetsushi; Fukuda, Keiichi; Ieda, Masaki

    2015-01-01

    Summary Fibroblasts can be directly reprogrammed into cardiomyocyte-like cells (iCMs) by overexpression of cardiac transcription factors, including Gata4, Mef2c, and Tbx5; however, this process is inefficient under serum-based culture conditions, in which conversion of partially reprogrammed cells into fully reprogrammed functional iCMs has been a major hurdle. Here, we report that a combination of fibroblast growth factor (FGF) 2, FGF10, and vascular endothelial growth factor (VEGF), termed FFV, promoted cardiac reprogramming under defined serum-free conditions, increasing spontaneously beating iCMs by 100-fold compared with those under conventional serum-based conditions. Mechanistically, FFV activated multiple cardiac transcriptional regulators and converted partially reprogrammed cells into functional iCMs through the p38 mitogen-activated protein kinase and phosphoinositol 3-kinase/AKT pathways. Moreover, FFV enabled cardiac reprogramming with only Mef2c and Tbx5 through the induction of cardiac reprogramming factors, including Gata4. Thus, defined culture conditions promoted the quality of cardiac reprogramming, and this finding provides new insight into the mechanism of cardiac reprogramming. PMID:26626177

  18. Stretching human mesenchymal stromal cells on stiffness-customized collagen type I generates a smooth muscle marker profile without growth factor addition

    NASA Astrophysics Data System (ADS)

    Rothdiener, Miriam; Hegemann, Miriam; Uynuk-Ool, Tatiana; Walters, Brandan; Papugy, Piruntha; Nguyen, Phong; Claus, Valentin; Seeger, Tanja; Stoeckle, Ulrich; Boehme, Karen A.; Aicher, Wilhelm K.; Stegemann, Jan P.; Hart, Melanie L.; Kurz, Bodo; Klein, Gerd; Rolauffs, Bernd

    2016-10-01

    Using matrix elasticity and cyclic stretch have been investigated for inducing mesenchymal stromal cell (MSC) differentiation towards the smooth muscle cell (SMC) lineage but not in combination. We hypothesized that combining lineage-specific stiffness with cyclic stretch would result in a significantly increased expression of SMC markers, compared to non-stretched controls. First, we generated dense collagen type I sheets by mechanically compressing collagen hydrogels. Atomic force microscopy revealed a nanoscale stiffness range known to support myogenic differentiation. Further characterization revealed viscoelasticity and stable biomechanical properties under cyclic stretch with >99% viable adherent human MSC. MSCs on collagen sheets demonstrated a significantly increased mRNA but not protein expression of SMC markers, compared to on culture flasks. However, cyclic stretch of MSCs on collagen sheets significantly increased both mRNA and protein expression of α-smooth muscle actin, transgelin, and calponin versus plastic and non-stretched sheets. Thus, lineage-specific stiffness and cyclic stretch can be applied together for inducing MSC differentiation towards SMCs without the addition of recombinant growth factors or other soluble factors. This represents a novel stimulation method for modulating the phenotype of MSCs towards SMCs that could easily be incorporated into currently available methodologies to obtain a more targeted control of MSC phenotype.

  19. Immunohistochemical expression of vascular endothelial growth factor in canine oral squamous cell carcinomas.

    PubMed

    Martano, Manuela; Restucci, Brunella; Ceccarelli, Dora Maria; Lo Muzio, Lorenzo; Maiolino, Paola

    2016-01-01

    Angiogenesis is crucial for the growth and metastasis of malignant tumours, and various proangiogenic factors promote this process. One of these factors is vascular endothelial growth factor (VEGF), which appears to play a key role in tumour angiogenesis. The aim of the present study was to assess whether VEGF expression is associated with angiogenesis, disease progression and neoplastic proliferation in canine oral squamous cell carcinoma (OSCC) tissue. VEGF immunoreactivity was quantified by immunohistochemistry in 30 specimens, including normal oral mucosa and OSCC tissues graded as well, moderately or poorly differentiated. VEGF expression was correlated with tumour cell proliferation, as assessed using the proliferating cell nuclear antigen (PCNA) marker and microvessel density (data already published). The present results revealed that VEGF and PCNA expression increased significantly between normal oral tissue and neoplastic tissue, and between well and moderately/poorly differentiated tumours. In addition, VEGF expression was strongly correlated with PCNA expression and microvessel density. It was concluded that VEGF may promote angiogenesis through a paracrine pathway, stimulating endothelial cell proliferation and, similarly, may induce tumour cell proliferation through an autocrine pathway. The present results suggest that the evaluation of VEGF may be a useful additional criterion for estimating malignancy and growth potential in canine OSCCs.

  20. Endorsement of Growth Factors in Experiential Training Groups

    ERIC Educational Resources Information Center

    Kiweewa, John; Gilbride, Dennis; Luke, Melissa; Seward, Derek

    2013-01-01

    The purpose of this study was to identify student growth factors during a semester long Master's level group counseling class. Results indicated that 12 growth factors accounted for 86% of the total number of critical incidents that participants reported as influencing their personal growth and awareness during the group experience. Two other…

  1. Fibroblast growth factor (FGF) signaling in development and skeletal diseases.

    PubMed

    Teven, Chad M; Farina, Evan M; Rivas, Jane; Reid, Russell R

    2014-12-01

    Fibroblast growth factors (FGF) and their receptors serve many functions in both the developing and adult organism. Humans contain 18 FGF ligands and four FGF receptors (FGFR). FGF ligands are polypeptide growth factors that regulate several developmental processes including cellular proliferation, differentiation, and migration, morphogenesis, and patterning. FGF-FGFR signaling is also critical to the developing axial and craniofacial skeleton. In particular, the signaling cascade has been implicated in intramembranous ossification of cranial bones as well as cranial suture homeostasis. In the adult, FGFs and FGFRs are crucial for tissue repair. FGF signaling generally follows one of three transduction pathways: RAS/MAP kinase, PI3/AKT, or PLCγ. Each pathway likely regulates specific cellular behaviors. Inappropriate expression of FGF and improper activation of FGFRs are associated with various pathologic conditions, unregulated cell growth, and tumorigenesis. Additionally, aberrant signaling has been implicated in many skeletal abnormalities including achondroplasia and craniosynostosis. The biology and mechanisms of the FGF family have been the subject of significant research over the past 30 years. Recently, work has focused on the therapeutic targeting and potential of FGF ligands and their associated receptors. The majority of FGF-related therapy is aimed at age-related disorders. Increased understanding of FGF signaling and biology may reveal additional therapeutic roles, both in utero and postnatally. This review discusses the role of FGF signaling in general physiologic and pathologic embryogenesis and further explores it within the context of skeletal development.

  2. Fibroblast growth factor (FGF) signaling in development and skeletal diseases

    PubMed Central

    Teven, Chad M.; Farina, Evan M.; Rivas, Jane; Reid, Russell R.

    2014-01-01

    Fibroblast growth factors (FGF) and their receptors serve many functions in both the developing and adult organism. Humans contain 18 FGF ligands and four FGF receptors (FGFR). FGF ligands are polypeptide growth factors that regulate several developmental processes including cellular proliferation, differentiation, and migration, morphogenesis, and patterning. FGF-FGFR signaling is also critical to the developing axial and craniofacial skeleton. In particular, the signaling cascade has been implicated in intramembranous ossification of cranial bones as well as cranial suture homeostasis. In the adult, FGFs and FGFRs are crucial for tissue repair. FGF signaling generally follows one of three transduction pathways: RAS/MAP kinase, PI3/AKT, or PLCγ. Each pathway likely regulates specific cellular behaviors. Inappropriate expression of FGF and improper activation of FGFRs are associated with various pathologic conditions, unregulated cell growth, and tumorigenesis. Additionally, aberrant signaling has been implicated in many skeletal abnormalities including achondroplasia and craniosynostosis. The biology and mechanisms of the FGF family have been the subject of significant research over the past 30 years. Recently, work has focused on the therapeutic targeting and potential of FGF ligands and their associated receptors. The majority of FGF-related therapy is aimed at age-related disorders. Increased understanding of FGF signaling and biology may reveal additional therapeutic roles, both in utero and postnatally. This review discusses the role of FGF signaling in general physiologic and pathologic embryogenesis and further explores it within the context of skeletal development. PMID:25679016

  3. Placenta Growth Factor in Diabetic Wound Healing

    PubMed Central

    Cianfarani, Francesca; Zambruno, Giovanna; Brogelli, Laura; Sera, Francesco; Lacal, Pedro Miguel; Pesce, Maurizio; Capogrossi, Maurizio C.; Failla, Cristina Maria; Napolitano, Monica; Odorisio, Teresa

    2006-01-01

    Reduced microcirculation and diminished expression of growth factors contribute to wound healing impairment in diabetes. Placenta growth factor (PlGF), an angiogenic mediator promoting pathophysiological neovascularization, is expressed during cutaneous wound healing and improves wound closure by enhancing angiogenesis. By using streptozotocin-induced diabetic mice, we here demonstrate that PlGF induction is strongly reduced in diabetic wounds. Diabetic transgenic mice overexpressing PlGF in the skin displayed accelerated wound closure compared with diabetic wild-type littermates. Moreover, diabetic wound treatment with an adenovirus vector expressing the human PlGF gene (AdCMV.PlGF) significantly accelerated the healing process compared with wounds treated with a control vector. The analysis of treated wounds showed that PlGF gene transfer improved granulation tissue formation, maturation, and vascularization, as well as monocytes/macrophages local recruitment. Platelet-derived growth factor, fibroblast growth factor-2, and vascular endothelial growth factor mRNA levels were increased in AdCMV.PlGF-treated wounds, possibly enhancing PlGF-mediated effects. Finally, PlGF treatment stimulated cultured dermal fibroblast migration, pointing to a direct role of PlGF in accelerating granulation tissue maturation. In conclusion, our data indicate that reduced PlGF expression contributes to impaired wound healing in diabetes and that PlGF gene transfer to diabetic wounds exerts therapeutic activity by promoting different aspects of the repair process. PMID:17003476

  4. Fibroblast Growth Factor 2: An Epithelial Ductal Cell Growth Inhibitor That Drops Out in Breast Cancer

    DTIC Science & Technology

    2011-10-01

    fibroblast   growth   factor   receptors  and  their  prognostic...AD_________________ Award Number: W81XWH-08-1-0708 TITLE: Fibroblast Growth Factor 2: an...September 2008 – 14 September 2011 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Fibroblast Growth Factor 2: an Epithelial Ductal Cell Growth

  5. Therapeutic angiogenesis: angiogenic growth factors for ischemic heart disease.

    PubMed

    Henning, Robert J

    2016-09-01

    Stem cells encode vascular endothelial growth factors (VEGFs), fibroblastic growth factors (FGFs), stem cell factor, stromal cell-derived factor, platelet growth factor and angiopoietin that can contribute to myocardial vascularization. VEGFs and FGFs are the most investigated growth factors. VEGFs regulate angiogenesis and vasculogenesis. FGFs stimulate vessel cell proliferation and differentiation and are regulators of endothelial cell migration, proliferation and survival. Clinical trials of VEGF or FGF for myocardial angiogenesis have produced disparate results. The efficacy of therapeutic angiogenesis can be improved by: (1) identifying the most optimal patients; (2) increased knowledge of angiogenic factor pharmacokinetics and proper dose; (3) prolonging contact of angiogenic factors with the myocardium; (4) increasing the efficiency of VEGF or FGF gene transduction; and (5) utilizing PET or MRI to measure myocardial perfusion and perfusion reserve.

  6. Clinical Application of Growth Factors and Cytokines in Wound Healing

    PubMed Central

    Barrientos, Stephan; Brem, Harold; Stojadinovic, Olivera; Tomic-Canic, Marjana

    2016-01-01

    Wound healing is a complex and dynamic biological process that involves the coordinated efforts of multiple cell types and is executed and regulated by numerous growth factors and cytokines. There has been a drive in the past two decades to study the therapeutic effects of various growth factors in the clinical management of non-healing wounds (e.g. pressure ulcers, chronic venous ulcers, diabetic foot ulcers). For this review, we conducted a nonline search of Medline and Pub Medical and critically analyzed the literature regarding the role of growth factors and cytokines in the management of these wounds. We focused on currently approved therapies, emerging therapies and future research possibilities. In this review we discuss four growth factors and cytokines currently being used on and off label for the healing of wounds. These include: granulocyte-macrophage colony stimulating factor (GM-CSF), platelet derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF). While the clinical results of using growth factors and cytokines are encouraging, many studies involved a small sample size and are disparate in measured endpoints. Therefore, further research is required to provide definitive evidence of efficacy. PMID:24942811

  7. Membrane type 1-matrix metalloproteinase cleaves off the NH2-terminal portion of heparin-binding epidermal growth factor and converts it into a heparin-independent growth factor.

    PubMed

    Koshikawa, Naohiko; Mizushima, Hiroto; Minegishi, Tomoko; Iwamoto, Ryo; Mekada, Eisuke; Seiki, Motoharu

    2010-07-15

    Epidermal growth factor (EGF) receptors (ErbB) and EGF family members represent promising targets for cancer therapy. Heparin-binding EGF (HB-EGF) is a member of the EGF family and is an important target for therapy in some types of human cancers. Processing of HB-EGF by proprotein convertases, and successively, by ADAM family proteases, generates a soluble growth factor that requires heparin as a cofactor. Although heparin potentiates HB-EGF activity in vitro, it is not clear how the heparin-binding activity of HB-EGF is regulated. Here, we show that membrane type 1-matrix metalloproteinase (MT1-MMP; MMP14), a potent invasion-promoting protease, markedly enhances HB-EGF-dependent tumor formation in mice. MT1-MMP additionally cleaves HB-EGF and removes the NH(2)-terminal 20 amino acids that are important for binding heparin. Consequently, the processing of HB-EGF by MT1-MMP converts HB-EGF into a heparin-independent growth factor with enhanced mitogenic activity, and thereby, expression of both proteins costimulates tumor cell growth in vitro and in vivo. The ErbB family of receptors expressed in human gastric carcinoma cells play a role in mediating enhanced HB-EGF activity by MT1-MMP during invasive cell growth in collagen. Thus, we shed light on a new mechanism whereby HB-EGF activity is regulated that should be considered when designing HB-EGF-targeted cancer therapy. (c)2010 AACR.

  8. Genetic Analysis of Fibroblast Growth Factor Signaling in the Drosophila Eye

    PubMed Central

    Mukherjee, T.; Choi, I.; Banerjee, Utpal

    2012-01-01

    The development of eyes in Drosophila involves intricate epithelial reorganization events for accurate positioning of cells and proper formation and organization of ommatidial clusters. We demonstrate that Branchless (Bnl), the fibroblast growth factor ligand, regulates restructuring events in the eye disc primordium from as early as the emergence of clusters from a morphogenetic front to the cellular movements during pupal eye development. Breathless (Btl) functions as the fibroblast growth factor receptor to mediate Bnl signal, and together they regulate expression of DE-cadherin, Crumbs, and Actin. In addition, in the eye Bnl regulates the temporal onset and extent of retinal basal glial cell migration by activating Btl in the glia. We hypothesized that the Bnl functions in the eye are Hedgehog dependent and represent novel aspects of Bnl signaling not explored previously. PMID:22384378

  9. Genetic analysis of fibroblast growth factor signaling in the Drosophila eye.

    PubMed

    Mukherjee, T; Choi, I; Banerjee, Utpal

    2012-01-01

    The development of eyes in Drosophila involves intricate epithelial reorganization events for accurate positioning of cells and proper formation and organization of ommatidial clusters. We demonstrate that Branchless (Bnl), the fibroblast growth factor ligand, regulates restructuring events in the eye disc primordium from as early as the emergence of clusters from a morphogenetic front to the cellular movements during pupal eye development. Breathless (Btl) functions as the fibroblast growth factor receptor to mediate Bnl signal, and together they regulate expression of DE-cadherin, Crumbs, and Actin. In addition, in the eye Bnl regulates the temporal onset and extent of retinal basal glial cell migration by activating Btl in the glia. We hypothesized that the Bnl functions in the eye are Hedgehog dependent and represent novel aspects of Bnl signaling not explored previously.

  10. Advances in pubertal growth and factors influencing it: Can we increase pubertal growth?

    PubMed Central

    Soliman, Ashraf; De Sanctis, Vincenzo; Elalaily, Rania; Bedair, Said

    2014-01-01

    Puberty is a period of development characterized by partially concurrent changes which includes growth acceleration, alteration in body composition and appearance of secondary sex characteristics. Puberty is characterized by an acceleration and then deceleration in skeletal growth. The initiation, duration and amount of growth vary considerably during the growth spurt. Pubertal growth and biological maturation are dynamic processes regulated by a variety of genetic and environmental factors. Changes in skeletal maturation and bone mineral accretion concomitant with the stage of pubertal development constitute essential components in the evaluation of growth during this pubertal period. Genetic, endocrine and nutritional factors and ethnicity contribute variably to the amount of growth gained during this important period of rapid changes. Many studies investigated the possibility of increasing pubertal growth to gain taller final adult height in adolescents with idiopathic short stature (ISS). The pattern of pubertal growth, its relation to sex maturity rating and factors affecting them has been addressed in this review. The results of different trials to increase final adult height of adolescents using different hormones have been summarized. These data enables Endocrinologists to give in-depth explanations to patients and families about the efficacy and clinical significance as well as the safety of using these therapies in the treatment of adolescents with ISS. PMID:25538878

  11. Controllable mineral coatings on scaffolds as carriers for growth factor release for bone tissue engineering

    NASA Astrophysics Data System (ADS)

    Saurez-Gonzalez, Darilis

    The work presented in this document, focused on the development and characterization of mineral coatings on scaffold materials to serve as templates for growth factor binding and release. Mineral coatings were formed using a biomimetic approach that consisted in the incubation of scaffolds in modified simulated body fluids (mSBF). To modulate the properties of the mineral coating, which we hypothesized would dictate growth factor release, we used carbonate (HCO3) concentration in mSBF of 4.2 mM, 25mM, and 100mM. Analysis of the mineral coatings formed using scanning electron microscopy indicated growth of a continuous layer of mineral with different morphologies. X-ray diffraction analysis showed peaks associated with hydroxyapatite. FTIR data confirmed the substitution of HCO3 in the mineral. As the extent of HCO3 substitution increased, the coating exhibited more rapid dissolution kinetics in an environment deficient in calcium and phosphate. The mineral coatings provided an effective mechanism for bioactive growth factor binding and release. Peptide versions of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2) were bound with efficiencies up to 90% to mineral-coated PCL scaffolds. Recombinant human vascular endothelial growth factor (rhVEGF) also bound to mineral coated scaffolds with lower efficiency (20%) and released with faster release kinetics compared to peptides growth factor. Released rhVEGF induced human umbilical vein endothelial cell (HUVEC) proliferation in vitro and enhanced blood vessel formation in vivo in an intramuscular sheep model. In addition to the use the mineral coatings for single growth factor release, we expanded the concept and bound both an angiogenic (rhVEGF) and osteogenic (mBMP2) growth factor by a simple double dipping process. Sustained release of both growth factors was demonstrated for over 60 days. Released rhVEGF enhanced blood vessel formation in vivo in sheep and its biological activity was

  12. Intracellular processing of epidermal growth factor. I. Acidification of 125I-epidermal growth factor in intracellular organelles.

    PubMed

    Matrisian, L M; Planck, S R; Magun, B E

    1984-03-10

    We previously reported that 125I-labeled epidermal growth factor is processed intracellularly to acidic macromolecules in Rat-1 fibroblasts. The present study defines the precursor-product relationship and localization of the processing steps to subcellular organelles by the use of a single isoelectric species of 125I-epidermal growth factor and Percoll gradient fractionation. The native pI 4.55 125I-epidermal growth factor was rapidly processed to a pI 4.2 species on or near the cell surface and in organelles corresponding to clathrin-coated vesicles, Golgi, and endoplasmic reticulum. This species was then processed to a pI 4.35 species in similar organelles. The pI 4.2 and 4.35 species were converted to a pI 4.0 species in dense, lysosome-like organelles. This species was ultimately degraded and exocytosed from the cell as low molecular weight products.

  13. Characterization of the growth of murine fibroblasts that express human insulin receptors. II. Interaction of insulin with other growth factors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Randazzo, P.A.; Jarett, L.

    1990-09-01

    The effects of insulin-like growth factor-1 (IGF-1), epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and insulin on DNA synthesis were studied in murine fibroblasts transfected with an expression vector containing human insulin receptor cDNA (NIH 3T3/HIR) and the parental NIH 3T3 cells. In NIH 3T3/HIR cells, individual growth factors in serum-free medium stimulated DNA synthesis with the following relative efficacies: insulin greater than or equal to 10% fetal calf serum greater than PDGF greater than IGF-1 much greater than EGF. In comparison, the relative efficacies of these factors in stimulating DNA synthesis by NIH 3T3 cells were 10% fetalmore » calf serum greater than PDGF greater than EGF much greater than IGF-1 = insulin. In NIH 3T3/HIR cells, EGF was synergistic with 1-10 ng/ml insulin but not with 100 ng/ml insulin or more. Synergy of PDGF or IGF-1 with insulin was not detected. In the parental NIH 3T3 cells, insulin and IGF-1 were found to be synergistic with EGF (1 ng/ml), PDGF (100 ng/ml), and PDGF plus EGF. In NIH 3T3/HIR cells, the lack of interaction of insulin with other growth factors was also observed when the percentage of cells synthesizing DNA was examined. Despite insulin's inducing only 60% of NIH 3T3/HIR cells to incorporate thymidine, addition of PDGF, EGF, or PDGF plus EGF had no further effect. In contrast, combinations of growth factors resulted in 95% of the parental NIH 3T3 cells synthesizing DNA. The independence of insulin-stimulated DNA synthesis from other mitogens in the NIH 3T3/HIR cells is atypical for progression factor-stimulated DNA synthesis and is thought to be partly the result of insulin receptor expression in an inappropriate context or quantity.« less

  14. Preimplantation embryo development in vitro: cooperative interactions among embryos and role of growth factors.

    PubMed Central

    Paria, B C; Dey, S K

    1990-01-01

    We have established a model that shows cooperative interaction among preimplantation embryos and the role of growth factors on their development and growth. Two-cell mouse embryos cultured singly in 25-microliters microdrops had inferior development to blastocysts and lower cell numbers per blastocyst compared with those cultured in groups of 5 or 10. The inferior development of singly cultured embryos was markedly improved by addition of epidermal growth factor (EGF) or transforming growth factor alpha or beta 1 (TGF-alpha or TGF-beta 1) to the culture medium. The stage of embryonic development, primarily affected by these treatments, was between eight-cell/morula and blastocyst. Furthermore, blastocysts developed from eight-cell embryos cultured in groups or singly in the presence of EGF showed a higher incidence of zona hatching compared with those cultured singly in the absence of EGF. Detection of EGF receptors on the embryonic cell surface at eight-cell/morula and blastocyst stages suggests beneficial effects of EGF or TGF-alpha on preimplantation embryo development and blastocyst functions. Insulin-like growth factor I (IGF-I) had no influence on embryo development. To further document the cooperative interactions among embryos, the volume of the culture medium was doubled to 50 microliters. This increase in culture volume was even more detrimental to the development of singly cultured embryos. However, this detrimental effect was significantly reversed by EGF and reversed even more markedly by a combination of EGF and TGF-beta 1 but not by TGF-beta 1 alone. Although TGF-beta 1 plus IGF-I caused a modest improvement of embryo development, the response was not as great as shown by EGF alone. Furthermore, IGF-I had no additive effect on EGF-induced embryonic development. The study presents clear evidence that specific growth factors of embryonic and/or reproductive tract origin participate in preimplantation embryo development and blastocyst functions in an

  15. The future of recombinant growth factors in wound healing.

    PubMed

    Robson, M C; Mustoe, T A; Hunt, T K

    1998-08-01

    For more than a decade, clinical trials have been conducted of the application of topical exogenous recombinant growth factors in attempts to accelerate the healing of chronic wounds. Although the results of some of these trials have been encouraging, overall the results have been somewhat discouraging. Much of the difficulty lies in the paucity of carefully controlled clinical trials of wound healing. Since wound healing is a complex process that can be influenced, both positively and negatively, by many factors, designing these trials has proved difficult. To date, only a single recombinant growth factor-recombinant human platelet-derived growth factor-BB (rhPDGF-BB)- has been approved by the US Food and Drug Administration; and that only for use in diabetic foot ulcers. It is unlikely, however, that a single growth factor will be able to resolve all issues of repair or strengthen all vulnerabilities of chronic wounds. Our expectation, therefore, is that growth factors, cytokines, and other biologic agents will be used more specifically in the future, for example, by targeting growth factor therapy at those specific components or processes that a given wound uses to heal.

  16. Recombinant Human Acidic Fibroblast Growth Factor (aFGF) Expressed in Nicotiana benthamiana Potentially Inhibits Skin Photoaging.

    PubMed

    Ha, Jang-Ho; Kim, Ha-Neul; Moon, Ki-Beom; Jeon, Jae-Heung; Jung, Dai-Hyun; Kim, Su-Jung; Mason, Hugh S; Shin, Seo-Yeon; Kim, Hyun-Soon; Park, Kyung-Mok

    2017-07-01

    Responding to the need for recombinant acidic fibroblast growth factor in the pharmaceutical and cosmetic industries, we established a scalable expression system for recombinant human aFGF using transient and a DNA replicon vector expression in Nicotiana benthamiana . Recombinant human-acidic fibroblast growth factor was recovered following Agrobacterium infiltration of N. benthamiana . The optimal time point at which to harvest recombinant human acidic fibroblast growth factor expressing leaves was found to be 4 days post-infiltration, before necrosis was evident. Commassie-stained SDS-PAGE gels of His-tag column eluates, concentrated using a 10 000 molecular weight cut-off column, showed an intense band at the expected molecular weight for recombinant human acidic fibroblast growth factor. An immunoblot confirmed that this band was recombinant human acidic fibroblast growth factor. Up to 10 µg recombinant human-acidic fibroblast growth factor/g of fresh leaves were achieved by a simple affinity purification protocol using protein extract from the leaves of agroinfiltrated N. benthamiana . The purified recombinant human acidic fibroblast growth factor improved the survival rate of UVB-irradiated HaCaT and CCD-986sk cells approximately 89 and 81 %, respectively. N. benthamiana -derived recombinant human acidic fibroblast growth factor showed similar effects on skin cell proliferation and UVB protection compared to those of Escherichia coli -derived recombinant human acidic fibroblast growth factor. Additionally, N. benthamiana- derived recombinant human acidic fibroblast growth factor increased type 1 procollagen synthesis up to 30 % as well as reduced UVB-induced intracellular reactive oxygen species generation in fibroblast (CCD-986sk) cells.UVB is a well-known factor that causes various types of skin damage and premature aging. Therefore, the present study demonstrated that N. benthamiana -derived recombinant human acidic fibroblast growth factor

  17. Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) expression in colorectal cancer.

    PubMed

    Nagano, Hideki; Goi, Takanori; Koneri, Kenji; Hirono, Yasuo; Katayama, Kanji; Yamaguchi, Akio

    2007-12-01

    Vascular endothelial growth factor (VEGF) is known as an important factor in the growth and metastasis of cancer cells. In 2001, a novel angiogenesis factor, endocrine gland-derived vascular endothelial growth factor (EG-VEGF), was cloned. In this study, we investigated the expression of EG-VEGF in colorectal cancer, the relationship between its expression and clinicopathological factors, and the in vitro activity of EG-VEGF transfectants. We determined expression levels of EG-VEGF in 113 advanced colorectal cancers resected in our hospital by quantitative PCR, and compared the expression levels and clinicopathological findings by multivariate analyses. The expression of EG-VEGF mRNA was positive in 31 cancers and negative in 82 cancers. We found that compared with the negative expression of the EG-VEGF gene, its positive expression was more frequently associated with hematogenous metastasis, and was associated with a poorer survival rate. In addition, EG-VEGF transfectants showed a higher degree of in vitro tubular formation than control cells. We speculate that, in colorectal cancers, the EG-VEGF gene functions as an important factor in angiogenesis in primary and metastatic lesions, and consider that it is useful as a novel prognostic factor. EG-VEGF molecule-targeted therapy has the potential for improving survival rates.

  18. 3D plotting of growth factor loaded calcium phosphate cement scaffolds.

    PubMed

    Akkineni, Ashwini Rahul; Luo, Yongxiang; Schumacher, Matthias; Nies, Berthold; Lode, Anja; Gelinsky, Michael

    2015-11-01

    Additive manufacturing allows to widely control the geometrical features of implants. Recently, we described the fabrication of calcium phosphate cement (CPC) scaffolds by 3D plotting of a storable CPC paste based on water-immiscible carrier liquid. Plotting and hardening is conducted under mild conditions allowing the (precise and local) integration of biological components. In this study, we have developed a procedure for efficient loading of growth factors in the CPC scaffolds during plotting and demonstrated the feasibility of this approach. Bovine serum albumin (BSA) or vascular endothelial growth factor (VEGF), used as model proteins, were encapsulated in chitosan/dextran sulphate microparticles which could be easily mixed into the CPC paste in freeze-dried state. In order to prevent leaching of the proteins during cement setting, usually carried out by immersion in aqueous solutions, the plotted scaffolds were aged in water-saturated atmosphere (humidity). Setting in humidity avoided early loss of loaded proteins but provided sufficient amount of water to allow cement setting, as indicated by XRD analysis and mechanical testing in comparison to scaffolds set in water. Moreover, humidity-set scaffolds were characterised by altered, even improved properties: no swelling or crack formation was observed and accordingly, surface topography, total porosity and compressive modulus of the humidity-set scaffolds differed from those of the water-set counterparts. Direct cultivation of mesenchymal stem cells on the humidity-set scaffolds over 21days revealed their cytocompatibility. Maintenance of the bioactivity of VEGF during the fabrication procedure was proven in indirect and direct culture experiments with endothelial cells. Additive manufacturing techniques allow the fabrication of implants with defined architecture (inner pore structure and outer shape). Especially printing technologies conducted under mild conditions allow additionally the (spatially controlled

  19. Fibroblast Growth Factors and Vascular Endothelial Growth Factor Promote Cardiac Reprogramming under Defined Conditions.

    PubMed

    Yamakawa, Hiroyuki; Muraoka, Naoto; Miyamoto, Kazutaka; Sadahiro, Taketaro; Isomi, Mari; Haginiwa, Sho; Kojima, Hidenori; Umei, Tomohiko; Akiyama, Mizuha; Kuishi, Yuki; Kurokawa, Junko; Furukawa, Tetsushi; Fukuda, Keiichi; Ieda, Masaki

    2015-12-08

    Fibroblasts can be directly reprogrammed into cardiomyocyte-like cells (iCMs) by overexpression of cardiac transcription factors, including Gata4, Mef2c, and Tbx5; however, this process is inefficient under serum-based culture conditions, in which conversion of partially reprogrammed cells into fully reprogrammed functional iCMs has been a major hurdle. Here, we report that a combination of fibroblast growth factor (FGF) 2, FGF10, and vascular endothelial growth factor (VEGF), termed FFV, promoted cardiac reprogramming under defined serum-free conditions, increasing spontaneously beating iCMs by 100-fold compared with those under conventional serum-based conditions. Mechanistically, FFV activated multiple cardiac transcriptional regulators and converted partially reprogrammed cells into functional iCMs through the p38 mitogen-activated protein kinase and phosphoinositol 3-kinase/AKT pathways. Moreover, FFV enabled cardiac reprogramming with only Mef2c and Tbx5 through the induction of cardiac reprogramming factors, including Gata4. Thus, defined culture conditions promoted the quality of cardiac reprogramming, and this finding provides new insight into the mechanism of cardiac reprogramming. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Endorsement of Growth Factors and Its Relation to Stage of Group Development in Experiential Groups

    ERIC Educational Resources Information Center

    Kiweewa, John M.

    2010-01-01

    This dissertation utilized critical incidents methodology to examine participants' endorsement of twelve primary growth factors during a Master's level group counseling class. Additionally, the study examined whether some factors are more salient than others at each stage of development (i.e., forming, storming, norming, performing) as defined by…

  1. Localisation of stem cell factor, stanniocalcin-1, connective tissue growth factor and heparin-binding epidermal growth factor in the bovine uterus at the time of blastocyst formation.

    PubMed

    Muñoz, M; Martin, D; Carrocera, S; Alonso-Guervos, M; Mora, M I; Corrales, F J; Peynot, N; Giraud-Delville, C; Duranthon, V; Sandra, O; Gómez, E

    2017-10-01

    Early embryonic losses before implantation account for the highest rates of reproductive failure in mammals, in particular when in vitro-produced embryos are transferred. In the present study, we used molecular biology techniques (real-time quantitative polymerase chain reaction), classical immunohistochemical staining coupled with confocal microscopy and proteomic analysis (multiple reaction monitoring and western blot analysis) to investigate the role of four growth factors in embryo-uterine interactions during blastocyst development. Supported by a validated embryo transfer model, the study investigated: (1) the expression of stem cell factor (SCF), stanniocalcin-1 (STC1), connective tissue growth factor (CTGF) and heparin-binding epidermal growth factor-like growth factor (HB-EGF) in bovine uterine fluid; (2) the presence of SCF, STC1, CTGF and HB-EGF mRNA and protein in the bovine endometrium and embryos; and (3) the existence of reciprocal regulation between endometrial and embryonic expression of SCF, STC1, CTGF and HB-EGF. The results suggest that these growth factors most likely play an important role during preimplantation embryo development in cattle. The information obtained from the present study can contribute to improving the performance of in vitro culture technology in cattle and other species.

  2. Unliganded fibroblast growth factor receptor 1 forms density-independent dimers.

    PubMed

    Comps-Agrar, Laëtitia; Dunshee, Diana Ronai; Eaton, Dan L; Sonoda, Junichiro

    2015-10-02

    Fibroblast growth factors receptors (FGFRs) are thought to initiate intracellular signaling cascades upon ligand-induced dimerization of the extracellular domain. Although the existence of unliganded FGFR1 dimers on the surface of living cells has been proposed, this notion remains rather controversial. Here, we employed time-resolved Förster resonance energy transfer combined with SNAP- and ACP-tag labeling in COS7 cells to monitor dimerization of full-length FGFR1 at the cell-surface with or without the coreceptor βKlotho. Using this approach we observed homodimerization of unliganded FGFR1 that is independent of its surface density. The homo-interaction signal observed for FGFR1 was indeed as robust as that obtained for epidermal growth factor receptor (EGFR) and was further increased by the addition of activating ligands or pathogenic mutations. Mutational analysis indicated that the kinase and the transmembrane domains, rather than the extracellular domain, mediate the ligand-independent FGFR1 dimerization. In addition, we observed a formation of a higher order ligand-independent complex by the c-spliced isoform of FGFR1 and βKlotho. Collectively, our approach provides novel insights into the assembly and dynamics of the full-length FGFRs on the cell surface. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Temporal expression of growth factors triggered by epiregulin regulates inflammation development.

    PubMed

    Harada, Masaya; Kamimura, Daisuke; Arima, Yasunobu; Kohsaka, Hitoshi; Nakatsuji, Yuji; Nishida, Makoto; Atsumi, Toru; Meng, Jie; Bando, Hidenori; Singh, Rajeev; Sabharwal, Lavannya; Jiang, Jing-Jing; Kumai, Noriko; Miyasaka, Nobuyuki; Sakoda, Saburo; Yamauchi-Takihara, Keiko; Ogura, Hideki; Hirano, Toshio; Murakami, Masaaki

    2015-02-01

    In this study, we investigated the relationship between several growth factors and inflammation development. Serum concentrations of epiregulin, amphiregulin, betacellulin, TGF-α, fibroblast growth factor 2, placental growth factor (PLGF), and tenascin C were increased in rheumatoid arthritis patients. Furthermore, local blockades of these growth factors suppressed the development of cytokine-induced arthritis in mice by inhibiting chemokine and IL-6 expressions. We found that epiregulin expression was early and followed by the induction of other growth factors at different sites of the joints. The same growth factors then regulated the expression of epiregulin at later time points of the arthritis. These growth factors were increased in patients suffering from multiple sclerosis (MS) and also played a role in the development of an MS model, experimental autoimmune encephalomyelitis. The results suggest that the temporal expression of growth factors is involved in the inflammation development seen in several diseases, including rheumatoid arthritis and MS. Therefore, various growth factor pathways might be good therapeutic targets for various inflammatory diseases. Copyright © 2015 by The American Association of Immunologists, Inc.

  4. Natural Killer Cells Promote Fetal Development through the Secretion of Growth-Promoting Factors.

    PubMed

    Fu, Binqing; Zhou, Yonggang; Ni, Xiang; Tong, Xianhong; Xu, Xiuxiu; Dong, Zhongjun; Sun, Rui; Tian, Zhigang; Wei, Haiming

    2017-12-19

    Natural killer (NK) cells are present in large populations at the maternal-fetal interface during early pregnancy. However, the role of NK cells in fetal growth is unclear. Here, we have identified a CD49a + Eomes + subset of NK cells that secreted growth-promoting factors (GPFs), including pleiotrophin and osteoglycin, in both humans and mice. The crosstalk between HLA-G and ILT2 served as a stimulus for GPF-secreting function of this NK cell subset. Decreases in this GPF-secreting NK cell subset impaired fetal development, resulting in fetal growth restriction. The transcription factor Nfil3, but not T-bet, affected the function and the number of this decidual NK cell subset. Adoptive transfer of induced CD49a + Eomes + NK cells reversed impaired fetal growth and rebuilt an appropriate local microenvironment. These findings reveal properties of NK cells in promoting fetal growth. In addition, this research proposes approaches for therapeutic administration of NK cells in order to reverse restricted nourishments within the uterine microenvironment during early pregnancy. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Adequate antipsychotic treatment normalizes serum nerve growth factor concentrations in schizophrenia with and without cannabis or additional substance abuse.

    PubMed

    Jockers-Scherübl, Maria C; Rentzsch, Johannes; Danker-Hopfe, Heidi; Radzei, Nicole; Schürer, Falk; Bahri, Sharif; Hellweg, Rainer

    2006-06-12

    Neurotrophins such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are important for the development and maintenance of neuron function. Neurodevelopment is thought to be impaired in schizophrenia, and vulnerable schizophrenic brains may be more sensitive to toxic influences. Thus, cannabis as a neurotoxin (and other substances) may be more harmful to schizophrenic brains than to non-schizophrenic brains, when used chronically. In a previous study we demonstrated an earlier disease onset and significantly higher serum NGF concentrations in drug-naïve schizophrenic patients with previous long-term cannabis abuse than in schizophrenics without cannabis abuse or cannabis abusers without schizophrenia. We therefore investigated whether this difference is still observed after treatment. Serum NGF measured in 114 treated schizophrenic patients (schizophrenia alone, n=66; schizophrenia plus cannabis abuse, n=42; schizophrenia plus multiple substance abuse, n=6) no longer differed significantly among those groups and from the control groups (healthy controls, n=51; cannabis controls, n=24; multiple substance controls, n=6). These results were confirmed by an additional prospective study in 28 patients suffering from schizophrenia (S) or schizophrenia with cannabis abuse (SC). Previously elevated serum NGF levels in the drug-naïve state, also differing between the groups (S: 83.44+/-265.25 pg/ml; SC: 246.89+/-310.24 pg/ml, S versus SC: p=0.03) dropped to 10.72+/-14.13 pg/ml (S) and 34.19+/-38.96 pg/ml (SC) (S versus SC, p>0.05), respectively, after adequate antipsychotic treatment. We thus conclude that antipsychotic treatment leads to recovery of neural integrity, as indicated by renormalized NGF values.

  6. Dual chain synthetic heparin-binding growth factor analogs

    DOEpatents

    Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY

    2012-04-24

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  7. Dual chain synthetic heparin-binding growth factor analogs

    DOEpatents

    Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY

    2009-10-06

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  8. Growth factors in urologic tissues: detection, characterization, and clinical applications.

    PubMed

    Mydlo, J H; Macchia, R J

    1992-12-01

    During the last two decades, enormous strides have been made in understanding cellular and molecular biology. The direction of treatment of many neoplasms and other diseases are starting at the microscopic level. Growth factors are polypeptides that play a part in the development and maintenance of living tissues. We, as well as others, have investigated the role that growth factors play particularly in urologic tissues, both benign and malignant. We review several well-known growth factors and their function in prostate, kidney, and bladder tissues, as well as their functions in other regulating processes of the human body, and also the use of growth factors as tumor markers, and antibodies to growth factors as possible treatment of disease.

  9. Platelets promote osteosarcoma cell growth through activation of the platelet-derived growth factor receptor-Akt signaling axis.

    PubMed

    Takagi, Satoshi; Takemoto, Ai; Takami, Miho; Oh-Hara, Tomoko; Fujita, Naoya

    2014-08-01

    The interactions of tumor cells with platelets contribute to the progression of tumor malignancy, and the expression levels of platelet aggregation-inducing factors positively correlate with the metastatic potential of osteosarcoma cells. However, it is unclear how tumor-platelet interaction contributes to the proliferation of osteosarcomas. We report here that osteosarcoma-platelet interactions induce the release of platelet-derived growth factor (PDGF) from platelets, which promotes the proliferation of osteosarcomas. Co-culture of platelets with MG63 or HOS osteosarcoma cells, which could induce platelet aggregation, enhanced the proliferation of each cell line in vitro. Analysis of phospho-antibody arrays revealed that co-culture of MG63 cells with platelets induced the phosphorylation of platelet derived growth factor receptor (PDGFR) and Akt. The addition of supernatants of osteosarcoma-platelet reactants also increased the growth of MG63 and HOS cells as well as the level of phosphorylated-PDGFR and -Akt. Sunitinib or LY294002, but not erlotinib, significantly inhibited the platelet-induced proliferation of osteosarcoma cells, indicating that PDGF released from platelets plays an important role in the proliferation of osteosarcomas by activating the PDGFR and then Akt. Our results suggest that inhibitors that specifically target osteosarcoma-platelet interactions may eradicate osteosarcomas. © 2014 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

  10. Interactions of cytokines, growth factors, and the extracellular matrix in the cellular biology of uterine leiomyomata.

    PubMed

    Sozen, Ibrahim; Arici, Aydin

    2002-07-01

    To review the available information regarding the role of cytokines, growth factors, and the extracellular matrix in the pathophysiology of uterine leiomyomata and to integrate this information in a suggested model of disease at the cellular level. A thorough literature and MEDLINE search was conducted to identify the relevant studies in the English literature published between January, 1966 and October, 2001. A model of disease at the cellular level was developed using the most likely cytokines to be involved in the pathogenesis of leiomyomata as determined by our assessment of the available literature. A number of cytokines and growth factors, including transforming growth factor-beta (TGF-beta), epidermal growth factor, monocyte chemotactic protein-1, insulin-like growth factors 1 and 2, prolactin, parathyroid-hormone-related peptide, basic fibroblast growth factor, platelet-derived growth factor, interleukin-8, and endothelin, have been investigated in myometrium and leiomyoma. Among these cytokines, TGF-beta appears to be the only growth factor that has been shown to be overexpressed in leiomyoma vs. myometrium, be hormonally-regulated both in vivo and in vitro, and be both mitogenic and fibrogenic in these tissues. In addition to the cytokines, extracellular matrix components such as collagen, fibronectin, proteoglycans, matrix metalloproteinases, and tissue inhibitors of metalloproteinases seem to play pivotal roles in the pathogenesis of leiomyomata. We believe that, given the extent and depth of the current research on the cellular biology of leiomyomata, the cellular mechanisms responsible in the pathogenesis of leiomyomata will be identified clearly within the foreseeable future. This will enable researchers to develop therapy directed against the molecules and mechanisms at the cellular level.

  11. Minoxidil Promotes Hair Growth through Stimulation of Growth Factor Release from Adipose-Derived Stem Cells

    PubMed Central

    Choi, Nahyun; Shin, Soyoung; Song, Sun U.; Sung, Jong-Hyuk

    2018-01-01

    Minoxidil directly promotes hair growth via the stimulation of dermal papilla (DP) and epithelial cells. Alternatively, there is little evidence for indirect promotion of hair growth via stimulation of adipose-derived stem cells (ASCs). We investigated whether minoxidil stimulates ASCs and if increased growth factor secretion by ASCs facilitates minoxidil-induced hair growth. Telogen-to-anagen induction was examined in mice. Cultured DP cells and vibrissae hair follicle organ cultures were used to further examine the underlying mechanisms. Subcutaneous injection of minoxidil-treated ASCs accelerated telogen-to-anagen transition in mice, and increased hair weight at day 14 post-injection. Minoxidil did not alter ASC proliferation, but increased migration and tube formation. Minoxidil also increased the secretion of growth factors from ASCs, including chemokine (C-X-C motif) ligand 1 (CXCL1), platelet-derived endothelial cell growth factor (PD-ECGF), and platelet-derived growth factor-C (PDGF-C). Minoxidil increased extracellular signal–regulated kinases 1/2 (ERK1/2) phosphorylation, and concomitant upregulation of PD-ECGF and PDGF-C mRNA levels were attenuated by an ERK inhibitor. Subcutaneous injection of CXCL1, PD-ECGF, or PDGF-C enhanced anagen induction in mice, and both CXCL1 and PDGF-C increased hair length in ex vivo organ culture. Treatment with CXCL1, PD-ECGF, or PDGF-C also increased the proliferation index in DP cells. Finally, topical application of CXCL1, PD-ECGF, or PDGF-C with 2% minoxidil enhanced anagen induction when compared to minoxidil alone. Minoxidil stimulates ASC motility and increases paracrine growth factor signaling. Minoxidil-stimulated secretion of growth factors by ASCs may enhance hair growth by promoting DP proliferation. Therefore, minoxidil can be used as an ASC preconditioning agent for hair regeneration. PMID:29495622

  12. Minoxidil Promotes Hair Growth through Stimulation of Growth Factor Release from Adipose-Derived Stem Cells.

    PubMed

    Choi, Nahyun; Shin, Soyoung; Song, Sun U; Sung, Jong-Hyuk

    2018-02-28

    Minoxidil directly promotes hair growth via the stimulation of dermal papilla (DP) and epithelial cells. Alternatively, there is little evidence for indirect promotion of hair growth via stimulation of adipose-derived stem cells (ASCs). We investigated whether minoxidil stimulates ASCs and if increased growth factor secretion by ASCs facilitates minoxidil-induced hair growth. Telogen-to-anagen induction was examined in mice. Cultured DP cells and vibrissae hair follicle organ cultures were used to further examine the underlying mechanisms. Subcutaneous injection of minoxidil-treated ASCs accelerated telogen-to-anagen transition in mice, and increased hair weight at day 14 post-injection. Minoxidil did not alter ASC proliferation, but increased migration and tube formation. Minoxidil also increased the secretion of growth factors from ASCs, including chemokine (C-X-C motif) ligand 1 (CXCL1), platelet-derived endothelial cell growth factor (PD-ECGF), and platelet-derived growth factor-C (PDGF-C). Minoxidil increased extracellular signal-regulated kinases 1/2 (ERK1/2) phosphorylation, and concomitant upregulation of PD-ECGF and PDGF-C mRNA levels were attenuated by an ERK inhibitor. Subcutaneous injection of CXCL1, PD-ECGF, or PDGF-C enhanced anagen induction in mice, and both CXCL1 and PDGF-C increased hair length in ex vivo organ culture. Treatment with CXCL1, PD-ECGF, or PDGF-C also increased the proliferation index in DP cells. Finally, topical application of CXCL1, PD-ECGF, or PDGF-C with 2% minoxidil enhanced anagen induction when compared to minoxidil alone. Minoxidil stimulates ASC motility and increases paracrine growth factor signaling. Minoxidil-stimulated secretion of growth factors by ASCs may enhance hair growth by promoting DP proliferation. Therefore, minoxidil can be used as an ASC preconditioning agent for hair regeneration.

  13. Genetic factors in fetal growth restriction and miscarriage.

    PubMed

    Yamada, Hideto; Sata, Fumihiro; Saijo, Yasuaki; Kishi, Reiko; Minakami, Hisanori

    2005-06-01

    Recently, several investigations concerning disadvantageous genetic factors in human reproduction have progressed. Inherited thrombophilia, such as factor V Leiden, prothrombin, and methylenetetrahydrofolate reductase mutations; gene polymorphisms of detoxification enzyme (CYP1A1); growth factors (insulin-like growth factor-I); and hormones such as angiotensinogen and CYP17 are involved in the pathogenesis of fetal growth restriction. The inherited thrombophilia, gene polymorphisms of coagulation and anticoagulation factor such as thrombomodulin, endothelial protein C receptor, plasminogen activator inhibitor 1, and factor XIII; human lymphocyte antigen (HLA-G); detoxification enzymes (glutathione- S-transferase M1); cytokines such as interleukin (IL) -1 and IL-6; hormones (CYP17); vasodilators (nitric oxide synthase 3); and vitamins (transcobalamin) are involved in the pathogenesis of sporadic and recurrent miscarriage. It is likely that a gene polymorphism or mutation susceptible to reproductive failure has a beneficial effect on the process of human reproduction with or without the environmental interaction. The factor V Leiden mutation has genetic advantages that are believed to be an improved implantation rate in in vitro fertilization and a reduction of maternal intrapartum blood loss. It has also been demonstrated that the CYP17 A2 allele has bidirectional effects on human reproduction, including increases in susceptibility to recurrent miscarriage and fetal growth enhancement.

  14. Fibroblast Growth Factor 23 and Kidney Disease Progression in Autosomal Dominant Polycystic Kidney Disease.

    PubMed

    Chonchol, Michel; Gitomer, Berenice; Isakova, Tamara; Cai, Xuan; Salusky, Isidro; Pereira, Renata; Abebe, Kaleab; Torres, Vicente; Steinman, Theodor I; Grantham, Jared J; Chapman, Arlene B; Schrier, Robert W; Wolf, Myles

    2017-09-07

    Increases in fibroblast growth factor 23 precede kidney function decline in autosomal dominant polycystic kidney disease; however, the role of fibroblast growth factor 23 in autosomal dominant polycystic kidney disease has not been well characterized. We measured intact fibroblast growth factor 23 levels in baseline serum samples from 1002 participants in the HALT-PKD Study A ( n =540; mean eGFR =91±17 ml/min per 1.73 m 2 ) and B ( n =462; mean eGFR =48±12 ml/min per 1.73 m 2 ). We used linear mixed and Cox proportional hazards models to test associations between fibroblast growth factor 23 and eGFR decline, percentage change in height-adjusted total kidney volume, and composite of time to 50% reduction in eGFR, onset of ESRD, or death. Median (interquartile range) intact fibroblast growth factor 23 was 44 (33-56) pg/ml in HALT-PKD Study A and 69 (50-93) pg/ml in Study B. In adjusted models, annualized eGFR decline was significantly faster in the upper fibroblast growth factor 23 quartile (Study A: quartile 4, -3.62; 95% confidence interval, -4.12 to -3.12 versus quartile 1, -2.51; 95% confidence interval, -2.71 to -2.30 ml/min per 1.73 m 2 ; P for trend <0.001; Study B: quartile 4, -3.74; 95% confidence interval, -4.14 to -3.34 versus quartile 1, -2.78; 95% confidence interval, -2.92 to -2.63 ml/min per 1.73 m 2 ; P for trend <0.001). In Study A, higher fibroblast growth factor 23 quartiles were associated with greater longitudinal percentage increase in height-adjusted total kidney volume in adjusted models (quartile 4, 6.76; 95% confidence interval, 5.57 to 7.96 versus quartile 1, 6.04; 95% confidence interval, 5.55 to 6.54; P for trend =0.03). In Study B, compared with the lowest quartile, the highest fibroblast growth factor 23 quartile was associated with elevated risk for the composite outcome (hazard ratio, 3.11; 95% confidence interval, 1.84 to 5.25). Addition of fibroblast growth factor 23 to a model of annualized decline in eGFR≥3.0 ml/min per 1.73 m

  15. Internalization Mechanisms of the Epidermal Growth Factor Receptor after Activation with Different Ligands

    PubMed Central

    Henriksen, Lasse; Grandal, Michael Vibo; Knudsen, Stine Louise Jeppe; van Deurs, Bo; Grøvdal, Lene Melsæther

    2013-01-01

    The epidermal growth factor receptor (EGFR) regulates normal growth and differentiation, but dysregulation of the receptor or one of the EGFR ligands is involved in the pathogenesis of many cancers. There are eight ligands for EGFR, however most of the research into trafficking of the receptor after ligand activation focuses on the effect of epidermal growth factor (EGF) and transforming growth factor-α (TGF-α). For a long time it was believed that clathrin-mediated endocytosis was the major pathway for internalization of the receptor, but recent work suggests that different pathways exist. Here we show that clathrin ablation completely inhibits internalization of EGF- and TGF-α-stimulated receptor, however the inhibition of receptor internalization in cells treated with heparin-binding EGF-like growth factor (HB-EGF) or betacellulin (BTC) was only partial. In contrast, clathrin knockdown fully inhibits EGFR degradation after all ligands tested. Furthermore, inhibition of dynamin function blocked EGFR internalization after stimulation with all ligands. Knocking out a number of clathrin-independent dynamin-dependent pathways of internalization had no effect on the ligand-induced endocytosis of the EGFR. We suggest that EGF and TGF-α lead to EGFR endocytosis mainly via the clathrin-mediated pathway. Furthermore, we suggest that HB-EGF and BTC also lead to EGFR endocytosis via a clathrin-mediated pathway, but can additionally use an unidentified internalization pathway or better recruit the small amount of clathrin remaining after clathrin knockdown. PMID:23472148

  16. Controlled growth factor release from synthetic extracellular matrices

    NASA Astrophysics Data System (ADS)

    Lee, Kuen Yong; Peters, Martin C.; Anderson, Kenneth W.; Mooney, David J.

    2000-12-01

    Polymeric matrices can be used to grow new tissues and organs, and the delivery of growth factors from these matrices is one method to regenerate tissues. A problem with engineering tissues that exist in a mechanically dynamic environment, such as bone, muscle and blood vessels, is that most drug delivery systems have been designed to operate under static conditions. We thought that polymeric matrices, which release growth factors in response to mechanical signals, might provide a new approach to guide tissue formation in mechanically stressed environments. Critical design features for this type of system include the ability to undergo repeated deformation, and a reversible binding of the protein growth factors to polymeric matrices to allow for responses to repeated stimuli. Here we report a model delivery system that can respond to mechanical signalling and upregulate the release of a growth factor to promote blood vessel formation. This approach may find a number of applications, including regeneration and engineering of new tissues and more general drug-delivery applications.

  17. Transforming growth factor-alpha short-circuits downregulation of the epidermal growth factor receptor.

    PubMed

    Ouyang, X; Gulliford, T; Huang, G; Epstein, R J

    1999-04-01

    Transforming growth factor-alpha (TGFalpha) is an epidermal growth factor receptor (EGFR) ligand which is distinguished from EGF by its acid-labile structure and potent transforming function. We recently reported that TGFalpha induces less efficient EGFR heterodimerization and downregulation than does EGF (Gulliford et al., 1997, Oncogene, 15:2219-2223). Here we use isoform-specific EGFR and ErbB2 antibodies to show that the duration of EGFR signalling induced by a single TGFalpha exposure is less than that induced by equimolar EGF. The protein trafficking inhibitor brefeldin A (BFA) reduces the duration of EGF signalling to an extent similar to that seen with TGFalpha alone; the effects of TGFalpha and BFA on EGFR degradation are opposite, however, with TGFalpha sparing EGFR from downregulation but BFA accelerating EGF-dependent receptor loss. This suggests that BFA blocks EGFR recycling and thus shortens EGF-dependent receptor signalling, whereas TGFalpha shortens receptor signalling and thus blocks EGFR downregulation. Consistent with this, repeated application of TGFalpha is accompanied by prolonged EGFR expression and signalling, whereas similar application of EGF causes receptor downregulation and signal termination. These findings indicate that constitutive secretion of pH-labile TGFalpha may perpetuate EGFR signalling by permitting early oligomer dissociation and dephosphorylation within acidic endosomes, thereby extinguishing a phosphotyrosine-based downregulation signal and creating an irreversible autocrine growth loop.

  18. Fibroblast growth factor-2 promotes keratan sulfate proteoglycan expression by keratocytes in vitro

    NASA Technical Reports Server (NTRS)

    Long, C. J.; Roth, M. R.; Tasheva, E. S.; Funderburgh, M.; Smit, R.; Conrad, G. W.; Funderburgh, J. L.

    2000-01-01

    Keratocytes of the corneal stroma produce a specialized extracellular matrix responsible for corneal transparency. Corneal keratan sulfate proteoglycans (KSPG) are unique products of keratocytes that are down-regulated in corneal wounds and in vitro. This study used cultures of primary bovine keratocytes to define factors affecting KSPG expression in vitro. KSPG metabolically labeled with [(35)S]sulfate decreased during the initial 2-4 days of culture in quiescent cultures with low serum concentrations (0.1%). Addition of fetal bovine serum, fibroblast growth factor-2 (FGF-2), transforming growth factor beta, or platelet derived growth factor all stimulated cell division, but only FGF-2 stimulated KSPG secretion. Combined with serum, FGF-2 also prevented serum-induced KSPG down-regulation. KSPG secretion was lost during serial subculture with or without FGF-2. Expression of KSPG core proteins (lumican, mimecan, and keratocan) was stimulated by FGF-2, and steady state mRNA pools for these proteins, particularly keratocan, were significantly increased by FGF-2 treatment. KSPG expression therefore is supported by exogenous FGF-2 and eliminated by subculture of the cells in presence of serum. FGF-2 stimulates KSPG core protein expression primarily through an increase in mRNA pools.

  19. Extracellular matrix and growth factors in branching morphogenesis

    NASA Technical Reports Server (NTRS)

    Hardman, P.; Spooner, B. S.

    1993-01-01

    The unifying hypothesis of the NSCORT in gravitational biology postulates that the ECM and growth factors are key interrelated components of a macromolecular regulatory system. The ECM is known to be important in growth and branching morphogenesis of embryonic organs. Growth factors have been detected in the developing embryo, and often the pattern of localization is associated with areas undergoing epithelial-mesenchymal interactions. Causal relationships between these components may be of fundamental importance in control of branching morphogenesis.

  20. Transforming growth factor-β1 promotes breast cancer metastasis by downregulating miR-196a-3p expression.

    PubMed

    Chen, Yan; Huang, Shai; Wu, Bo; Fang, Jiankai; Zhu, Minsheng; Sun, Li; Zhang, Lifeng; Zhang, Yongsheng; Sun, Maomin; Guo, Lingling; Wang, Shouli

    2017-07-25

    Transforming growth factor-β1 is considered a key contributor to the progression of breast cancer. MicroRNAs are important factors in the development and progression of many malignancies. In the present study, upon studies of breast cancer cell lines and tissues, we showed that microRNA -196a-3p is decreased by transforming growth factor-β1 in breast cancer cells and associated with breast cancer progression. We identified neuropilin-2 as a target gene of microRNA -196a-3p and showed that it is regulated by transforming growth factor-β1. Moreover, transforming growth factor-β1-mediated inhibition of microRNA -196a-3p and activation of neuropilin-2were required for transforming growth factor-β1-induced migration and invasion of breast cancer cells. In addition, neuropilin-2 expression was suppressed in breast tumors, particularly in triple-negative breast cancers. Collectively, our findings strongly indicate that microRNA -196a-3p is a predictive biomarker of breast cancer metastasis and patient survival and a potential therapeutic target in metastatic breast cancer.

  1. Fibroblast Growth Factors Stimulate Hair Growth through β-Catenin and Shh Expression in C57BL/6 Mice

    PubMed Central

    Lin, Wei-hong; Xiang, Li-Jun; Shi, Hong-Xue; Zhang, Jian; Jiang, Li-ping; Cai, Ping-tao; Lin, Zhen-Lang; Lin, Bei-Bei; Huang, Yan; Zhang, Hai-Lin; Fu, Xiao-Bing; Guo, Ding-Jiong; Li, Xiao-Kun; Wang, Xiao-Jie; Xiao, Jian

    2015-01-01

    Growth factors are involved in the regulation of hair morphogenesis and cycle hair growth. The present study sought to investigate the hair growth promoting activities of three approved growth factor drugs, fibroblast growth factor 10 (FGF-10), acidic fibroblast growth factor (FGF-1), and basic fibroblast growth factor (FGF-2), and the mechanism of action. We observed that FGFs promoted hair growth by inducing the anagen phase in telogenic C57BL/6 mice. Specifically, the histomorphometric analysis data indicates that topical application of FGFs induced an earlier anagen phase and prolonged the mature anagen phase, in contrast to the control group. Moreover, the immunohistochemical analysis reveals earlier induction of β-catenin and Sonic hedgehog (Shh) in hair follicles of the FGFs-treated group. These results suggest that FGFs promote hair growth by inducing the anagen phase in resting hair follicles and might be a potential hair growth-promoting agent. PMID:25685806

  2. Factors driving mortality and growth at treeline: a 30-year experiment of 92 000 conifers.

    PubMed

    Barbeito, Ignacio; Dawes, Melissa A; Rixen, Christian; Senn, Josef; Bebi, Peter

    2012-02-01

    Understanding the interplay between environmental factors contributing to treeline formation and how these factors influence different life stages remains a major research challenge. We used an afforestation experiment including 92 000 trees to investigate the spatial and temporal dynamics of tree mortality and growth at treeline in the Swiss Alps. Seedlings of three high-elevation conifer species (Larix decidua, Pinus mugo ssp. uncinata, and Pinus cembra) were systematically planted along an altitudinal gradient at and above the current treeline (2075 to 2230 m above sea level [a.s.l.]) in 1975 and closely monitored during the following 30 years. We used decision-tree models and generalized additive models to identify patterns in mortality and growth along gradients in elevation, snow duration, wind speed, and solar radiation, and to quantify interactions between the different variables. For all three species, snowmelt date was always the most important environmental factor influencing mortality, and elevation was always the most important factor for growth over the entire period studied. Individuals of all species survived at the highest point of the afforestation for more than 30 years, although mortality was greater above 2160 m a.s.l., 50-100 m above the current treeline. Optimal conditions for height growth differed from those for survival in all three species: early snowmelt (ca. day of year 125-140 [where day 1 is 1 January]) yielded lowest mortality rates, but relatively later snowmelt (ca. day 145-150) yielded highest growth rates. Although snowmelt and elevation were important throughout all life stages of the trees, the importance of radiation decreased over time and that of wind speed increased. Our findings provide experimental evidence that tree survival and height growth require different environmental conditions and that even small changes in the duration of snow cover, in addition to changes in temperature, can strongly impact tree survival and

  3. Effect of growth factors on hyaluronan production by canine vocal fold fibroblasts.

    PubMed

    Hirano, Shigeru; Bless, Diane M; Heisey, Dennis; Ford, Charles N

    2003-07-01

    Hyaluronan (HYA) is considered to be a crucial factor in scarless wound healing and in maintaining tissue viscosity of the vocal fold lamina propria. In this study focusing on the effects of growth factors, we examined how HYA is produced and controlled in canine cultured vocal fold fibroblasts. Fibroblasts were taken from the lamina propria of the vocal folds of 8 dogs and cultured with and without growth factors. The production of HYA in the supernatant culture was quantitatively examined by enzyme-linked immunosorbent assay. Hepatocyte growth factor, epidermal growth factor, basic fibroblast growth factor, and transforming growth factor beta1 all stimulated HYA synthesis from vocal fold fibroblasts. These effects differed with the concentration of growth factors and the incubation period. We also examined how frequently the growth factors had to be administered in order to maintain appropriate levels of HYA. A single administration was sufficient to maintain appropriate HYA levels for at least 7 days. The present studies have demonstrated positive effects of growth factors in stimulating HYA production. Further in vivo study is needed to clarify the usefulness of these growth factors in the management of vocal fold scarring.

  4. Alterations of Growth Factors in Autism and Attention-Deficit/Hyperactivity Disorder

    PubMed Central

    Galvez-Contreras, Alma Y.; Campos-Ordonez, Tania; Gonzalez-Castaneda, Rocio E.; Gonzalez-Perez, Oscar

    2017-01-01

    Growth factors (GFs) are cytokines that regulate the neural development. Recent evidence indicates that alterations in the expression level of GFs during embryogenesis are linked to the pathophysiology and clinical manifestations of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASD). In this concise review, we summarize the current evidence that supports the role of brain-derived neurotrophic factor, insulin-like growth factor 2, hepatocyte growth factor (HGF), glial-derived neurotrophic factor, nerve growth factor, neurotrophins 3 and 4, and epidermal growth factor in the pathogenesis of ADHD and ASD. We also highlight the potential use of these GFs as clinical markers for diagnosis and prognosis of these neurodevelopmental disorders. PMID:28751869

  5. Epidermal growth factor in alkali-burned corneal epithelial wound healing.

    PubMed

    Singh, G; Foster, C S

    1987-06-15

    We conducted a double-masked study to evaluate the effect of epidermal growth factor on epithelial wound healing and recurrent erosions in alkali-burned rabbit corneas. Epithelial wounds 10 mm in diameter healed completely under the influence of topical epidermal growth factor, whereas the control corneas did not resurface in the center. On reversal of treatment, the previously nonhealing epithelial defects healed when treated with topical epidermal growth factor eyedrops. Conversely, the epidermal growth factor-treated and resurfaced corneas developed epithelial defects when treatment was discontinued. Histopathologic examination disclosed hyperplastic epithelium growing over the damaged stroma laden with polymorphonuclear leukocytes when treated with epidermal growth factor eyedrops, but it did not adhere to the underlying tissue. Hydropic changes were seen intracellularly as well as between the epithelial cells and the stroma.

  6. Human corpus luteum: presence of epidermal growth factor receptors and binding characteristics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ayyagari, R.R.; Khan-Dawood, F.S.

    Epidermal growth factor receptors are present in many reproductive tissues but have not been demonstrated in the human corpus luteum. To determine the presence of epidermal growth factor receptors and its binding characteristics, we carried out studies on the plasma cell membrane fraction of seven human corpora lutea (days 16 to 25) of the menstrual cycle. Specific epidermal growth factor receptors were present in human corpus luteum. Insulin, nerve growth factor, and human chorionic gonadotropin did not competitively displace epidermal growth factor binding. The optimal conditions for corpus luteum-epidermal growth factor receptor binding were found to be incubation for 2more » hours at 4 degrees C with 500 micrograms plasma membrane protein and 140 femtomol /sup 125/I-epidermal growth factor per incubate. The number (mean +/- SEM) of epidermal growth factor binding sites was 12.34 +/- 2.99 X 10(-19) mol/micrograms protein; the dissociation constant was 2.26 +/- 0.56 X 10(-9) mol/L; the association constant was 0.59 +/- 0.12 X 10(9) L/mol. In two regressing corpora lutea obtained on days 2 and 3 of the menstrual cycle, there was no detectable specific epidermal growth factor receptor binding activity. Similarly no epidermal growth factor receptor binding activity could be detected in ovarian stromal tissue. Our findings demonstrate that specific receptors for epidermal growth factor are present in the human corpus luteum. The physiologic significance of epidermal growth factor receptors in human corpus luteum is unknown, but epidermal growth factor may be involved in intragonadal regulation of luteal function.« less

  7. Non-identical distribution pattern of epidermal growth factor and platelet-derived growth factor in the mouse uterus during the oestrous cycle and early pregnancy.

    PubMed

    Jaber, L; Kan, F W

    1998-10-01

    In the present study, we examined by immunohistochemistry the cell-specific distribution of epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) in the mouse uterus during the oestrous cycle and throughout the first 7 days of pregnancy. Paraffin-embedded tissue samples were immunostained using the avidin-biotin peroxidase technique and then examined by light microscopy. Our results showed that immunostaining for EGF was detected in the stroma but not in the luminal or glandular epithelium. A high concentration of EGF was detected in the stroma around the time of embryo implantation at days 3, 4 and 5 of pregnancy. The implanted embryo at day 7 of gestation showed immunostaining for EGF between the ectoderm and endoderm layers. The cell distribution pattern for PDGF was found to be different from that observed with EGF. Luminal and glandular epithelia displayed PDGF immunostaining throughout the first 7 days of pregnancy, with the highest intensity at days 4 and 5 of gestation. In contrast, no immunostaining was observed in the luminal and glandular epithelia at post-oestrus, dioestrus and pro-oestrus stages. However, a weak reaction started to appear at oestrus. The embryo at the blastocyst stage displayed a strong immunoreaction for antibody against PDGF. In addition, the decidual boundary zone surrounding the implanted embryo at days 5, 6 and 7 of gestation also showed an immunostaining for PDGF. The present observations demonstrate clearly the presence of EGF and PDGF in the mouse uterus in high concentrations at the peri-implantation period. Thus, our results, together with what is known about the effect of EGF and PDGF in controlling the growth, differentiation and activation of a variety of cell types, suggest a possible role for these growth factors during the preparation of the endometrium for implantation in controlling the proliferation activity of stromal and/or epithelial cells.

  8. DNA copy number gains at loci of growth factors and their receptors in salivary gland adenoid cystic carcinoma.

    PubMed

    Vékony, Hedy; Ylstra, Bauke; Wilting, Saskia M; Meijer, Gerrit A; van de Wiel, Mark A; Leemans, C René; van der Waal, Isaäc; Bloemena, Elisabeth

    2007-06-01

    Adenoid cystic carcinoma (ACC) is a malignant salivary gland tumor with a high mortality rate due to late, distant metastases. This study aimed at unraveling common genetic abnormalities associated with ACC. Additionally, chromosomal changes were correlated with patient characteristics and survival. Microarray-based comparative genomic hybridization was done to a series of 18 paraffin-embedded primary ACCs using a genome-wide scanning BAC array. A total of 238 aberrations were detected, representing more gains than losses (205 versus 33, respectively). Most frequent gains (>60%) were observed at 9q33.3-q34.3, 11q13.3, 11q23.3, 19p13.3-p13.11, 19q12-q13.43, 21q22.3, and 22q13.33. These loci harbor numerous growth factor [fibroblast growth factor (FGF) and platelet-derived growth factor (PDGF)] and growth factors receptor (FGFR3 and PDGFRbeta) genes. Gains at the FGF(R) regions occurred significantly more frequently in the recurred/metastasized ACCs compared with indolent ACCs. Furthermore, patients with 17 or more chromosomal aberrations had a significantly less favorable outcome than patients with fewer chromosomal aberrations (log-rank = 5.2; P = 0.02). Frequent DNA copy number gains at loci of growth factors and their receptors suggest their involvement in ACC initiation and progression. Additionally, the presence of FGFR3 and PDGFRbeta in increased chromosomal regions suggests a possible role for autocrine stimulation in ACC tumorigenesis.

  9. Predictive factors for intrauterine growth restriction.

    PubMed

    Albu, A R; Anca, A F; Horhoianu, V V; Horhoianu, I A

    2014-06-15

    Reduced fetal growth is seen in about 10% of the pregnancies but only a minority has a pathological background and is known as intrauterine growth restriction or fetal growth restriction (IUGR / FGR). Increased fetal and neonatal mortality and morbidity as well as adult pathologic conditions are often associated to IUGR. Risk factors for IUGR are easy to assess but have poor predictive value. For the diagnostic purpose, biochemical serum markers, ultrasound and Doppler study of uterine and spiral arteries, placental volume and vascularization, first trimester growth pattern are object of assessment today. Modern evaluations propose combined algorithms using these strategies, all with the goal of a better prediction of risk pregnancies.

  10. Growth status of children in well-baby outpatient clinics and related factors.

    PubMed

    Çelik, Sercan Bulut; Şahin, Figen; Beyazova, Ufuk; Can, Hüseyin

    2014-06-01

    The aim of this study was to determine the state of growth during follow-up of healthy children and the factors affecting growth. The patient cards of the infants who were born in 2002 and followed up in the well-baby outpatient clinic in Gazi University, Medical Faculty regularly for at least 18 months were examined retrospectively. Their sociodemographic properties including age, education level, occupation of the parents, if the mother was working, caretakers and gender, gestational week, birth weight, birth height and mode of nutrition (breastmilk, formula, cow's milk, period of feeding, etc.) and growth of the babies (month, percentile) were recorded. Number of siblings and ages of the siblings were also recorded and the children with and without growth problems were compared in terms of these properties. It was found that 290 (39.3%) of 739 children who were followed up continued to grow up in the percentile in which they started (normal growth), 188 (25.4%) lost 2 or more percentiles in any month (growth retardation) and 261 (35.3%) lost less than 2 percentiles (decelerated growth). Deceleration/retardation in growth was observed most commonly in the 9(th) month. Deceleration in growth was found in the 6(th) month in 23.6% of the group with deceleration in growth, in the 9(th) month in 50.2%, in the 12(th) month in 15.8% and in the 18(th) month in 3.9%. Growth retardation was found in the 6(th) month in 35.8% of the group with growth retardation, in the 9(th) month in 38.0% and in the 18(th) month in 4.3%. It was found that receiving formula and presence of infection were the main risk factors in terms of deceleration of growth and unemployed mother, the lenght of the total time of breastfeeding and presence of infection were the main risk factors in terms of growth retardation. This study shows the importance of follow-up of growth of children in outpatient clinics for healthy children. It was found that detailed examination and recording of non

  11. The additive effects of minoxidil and retinol on human hair growth in vitro.

    PubMed

    Yoo, Hyeon Gyeong; Chang, In-Young; Pyo, Hyun Keol; Kang, Yong Jung; Lee, Seung Ho; Kwon, Oh Sang; Cho, Kwang Hyun; Eun, Hee Chul; Kim, Kyu Han

    2007-01-01

    Minoxidil enhances hair growth by prolonging the anagen phase and induces new hair growth in androgenetic alopecia (AGA), whereas retinol significantly improves scalp skin condition and promotes hair growth. We investigated the combined effects of minoxidil and retinol on human hair growth in vitro and on cultured human dermal papilla cells (DPCs) and epidermal keratinocytes (HaCaT). The combination of minoxidil and retinol additively promoted hair growth in hair follicle organ cultures. In addition, minoxidil plus retinol more effectively elevated phosphorylated Erk, phosphorylated Akt levels, and the Bcl-2/Bax ratio than minoxidil alone in DPCs and HaCaT. We found that the significant hair shaft elongation demonstrated after minoxidil plus retinol treatment would depend on the dual kinetics associated with the activations of Erk- and Akt-dependent pathways and the prevention of apoptosis by increasing the Bcl-2/Bax ratio.

  12. 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

  13. Carcass analog addition enhances juvenile Atlantic salmon (Salmo salar) growth and condition

    USGS Publications Warehouse

    Guyette, Margaret Q.; Loftin, Cynthia S.; Zydlewski, Joseph D.

    2013-01-01

    Our study used historic marine-derived nutrient (MDN) delivery timing to simulate potential effects of restored connectivity on juvenile Atlantic salmon (ATS; Salmo salar) growth and condition. Four headwater streams were stocked with ATS young of the year (YOY) and received carcass analog additions (0.10 kg·m–2 wetted area) in treatment reaches to match the timing of sea lamprey (Petromyzon marinus) spawning. Individual ATS mass was 33%–48% greater and standard length was 9%–15% greater in treatment reaches relative to control reaches for 4 months following nutrient additions. Percent total lipids in YOY ATS were twice as great in treatment reaches 1 month following carcass analog additions and remained elevated in treatment fish for 2 more months. Absolute growth rates, based on otolith microstructure analysis, correlated with water temperature fluctuations in all reaches and were elevated by an average of 0.07 mm·day–1 in treatment reaches for 1 month following carcass analog additions. Simulated sea lamprey MDNs increased juvenile ATS growth, which, via potential increases in overwinter survival and decreases in smolt age, may contribute to population persistence and ecosystem productivity.

  14. NUCLEAR FACTOR Y Transcription Factors Have Both Opposing and Additive Roles in ABA-Mediated Seed Germination

    PubMed Central

    Kumimoto, Roderick W.; Siriwardana, Chamindika L.; Gayler, Krystal K.; Risinger, Jan R.; Siefers, Nicholas; Holt, Ben F.

    2013-01-01

    In the model organism Arabidopsis thaliana the heterotrimeric transcription factor NUCLEAR FACTOR Y (NF-Y) has been shown to play multiple roles in facilitating plant growth and development. Although NF-Y itself represents a multi-protein transcriptional complex, recent studies have shown important interactions with other transcription factors, especially those in the bZIP family. Here we add to the growing evidence that NF-Y and bZIP form common complexes to affect many processes. We carried out transcriptional profiling on nf-yc mutants and through subsequent analyses found an enrichment of bZIP binding sites in the promoter elements of misregulated genes. Using NF-Y as bait, yeast two hybrid assays yielded interactions with bZIP proteins that are known to control ABA signaling. Accordingly, we find that plants mutant for several NF-Y subunits show characteristic phenotypes associated with the disruption of ABA signaling. While previous reports have shown additive roles for NF-YC family members in photoperiodic flowering, we found that they can have opposing roles in ABA signaling. Collectively, these results demonstrated the importance and complexity of NF-Y in the integration of environmental and hormone signals. PMID:23527203

  15. Posttraumatic growth in bereaved parents: A multidimensional model of associated factors.

    PubMed

    Albuquerque, Sara; Narciso, Isabel; Pereira, Marco

    2018-03-01

    Although the death of a child is a devastating event, recent evidence shows that personal growth is a relevant outcome of parents' grief. This study aimed to examine the factors associated with posttraumatic growth (PTG) and to propose a multidimensional model consisting of sociodemographic, situational, and intrapersonal and interpersonal factors. A sample (N = 197; 89.8% female; mean age = 39.44 years) of bereaved parents completed the Post-Traumatic Growth Inventory-Short Form, the 14-Item Resilience Scale, the Continuing Bonds Scale, and the Dyadic Coping Inventory. The final model consisted of sociodemographic, situational, intrapersonal, and interpersonal factors of PTG, which accounted for 36.7% of the variance. Higher levels of PTG were generally associated with female sex, younger age of the child, higher levels of resilience, higher levels of internalized continuing bonds (i.e., internal representation of the child, maintaining psychological proximity), and higher levels of stress communication by the partner (communicating the stress experience and requesting emotional or practical support). In clinical practice, health professionals assisting bereaved parents should pay attention to men and parents of older children, who might be at higher risk of difficulties in developing PTG. Additionally, promoting a more internalized bond with the child, resilience and dyadic coping, especially stress communication, can constitute important therapeutic goals. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  16. Activity of insulin growth factors and shrimp neurosecretory organ extracts on a lepidopteran cell line.

    PubMed

    Hatt, P J; Liebon, C; Morinière, M; Oberlander, H; Porcheron, P

    1997-01-01

    Ecdysteroids, or molting hormones, have been proven to be key differentiation regulators for epidermal cells in the postembryonic development of arthropods. Regulators of cell proliferation, however, remain largely unknown. To date, no diffusible insect peptidic growth factors have been characterized. Molecules structurally related to insulin have been discovered in insects, as in other eucaryotes. We developed in vitro tests for the preliminary characterization of potential growth factors in arthropods by adapting the procedures designed to detect such factors in vertebrates to an insect cell line (IAL-PID2) established from imaginal discs of the Indian meal moth. We verified the ability of these tests to measure the proliferation of IAL-PID2 cells. We tested mammalian insulin and insulin-like growth factors (IGF-I, IGF-II). Following an arrest of cell proliferation by serum deprivation, IGF-I and IGF-II caused partial resumption of the cell cycle, evidenced by DNA synthesis. In contrast, the addition of 20-hydroxyecdysone arrested the proliferation of the IAL-PID2 cells. The cell line was then used in a test for functional characterization of potential growth factors originating from the penaeid shrimp, Penaeus vannamei. Crude extracts of neurosecretory and nervous tissues, eyestalks, and ventral neural chain compensated for serum deprivation and stimulated completion of mitosis. Arch.

  17. 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.

  18. Potential role of fibroblast growth factor in enhancement of fracture healing.

    PubMed

    Radomsky, M L; Thompson, A Y; Spiro, R C; Poser, J W

    1998-10-01

    Fibroblast growth factors are present in significant amounts in bone and several studies have suggested that they may be involved in normal fracture healing. It is well established that fibroblast growth factors have mitogenic and angiogenic activity on mesoderm and neuroectoderm derived cells. Of particular interest as a member of the fibroblast growth factor family, basic fibroblast growth factor stimulates mitogenesis, chemotaxis, differentiation, and angiogenesis. It also plays an important role in the development of vascular, nervous, and skeletal systems, promotes the maintenance and survival of certain tissues, and stimulates wound healing and tissue repair. Animal studies have shown that the direct injection of fibroblast growth factor into fresh fractures stimulates callus formation, which provides mechanical stability to the fracture, accelerates healing, and restores competence. The matrix used to present the fibroblast growth factor at the fracture site plays a critical role in the effectiveness of the treatment. The evaluation of injectable basic fibroblast growth factor in a sodium hyaluronate gel for its effectiveness in stimulating fracture healing is described. When applied directly into a freshly created fracture in the rabbit fibula, a single injection of the basic fibroblast growth factor and hyaluronan results in the stimulation of callus formation, increased bone formation, and earlier restoration of mechanical strength at the fracture site. The hyaluronan gel serves as a reservoir that sequesters the basic fibroblast growth factor at the injection site for the length of time necessary to create an environment conducive to fracture healing. It is concluded that basic fibroblast growth factor and sodium hyaluronate act synergistically to accelerate fracture healing and that the combination is suitable for clinical evaluation as a therapy in fracture treatment.

  19. Neural Stem Cell Differentiation Using Microfluidic Device-Generated Growth Factor Gradient.

    PubMed

    Kim, Ji Hyeon; Sim, Jiyeon; Kim, Hyun-Jung

    2018-04-11

    Neural stem cells (NSCs) have the ability to self-renew and differentiate into multiple nervous system cell types. During embryonic development, the concentrations of soluble biological molecules have a critical role in controlling cell proliferation, migration, differentiation and apoptosis. In an effort to find optimal culture conditions for the generation of desired cell types in vitro , we used a microfluidic chip-generated growth factor gradient system. In the current study, NSCs in the microfluidic device remained healthy during the entire period of cell culture, and proliferated and differentiated in response to the concentration gradient of growth factors (epithermal growth factor and basic fibroblast growth factor). We also showed that overexpression of ASCL1 in NSCs increased neuronal differentiation depending on the concentration gradient of growth factors generated in the microfluidic gradient chip. The microfluidic system allowed us to study concentration-dependent effects of growth factors within a single device, while a traditional system requires multiple independent cultures using fixed growth factor concentrations. Our study suggests that the microfluidic gradient-generating chip is a powerful tool for determining the optimal culture conditions.

  20. Melasma treatment: A novel approach using a topical agent that contains an anti-estrogen and a vascular endothelial growth factor inhibitor.

    PubMed

    Cohen, Philip R

    2017-04-01

    Melasma is an acquired disorder of pigmentation that presents with asymptomatic symmetric darkening of the face. The pathogenesis of this condition is multifactorial and influenced by several factors including female sex hormones, genetic predisposition and ultraviolet light exposure. The management of melasma is usually directed at more than one of the causative etiologic factors and often incorporates a combination of topical agents, with or without the addition of physical modalities. Estrogen and angiogenesis are significant factors in the etiology of melasma. A useful addition to the therapeutic armentarium for treating melasma would include a topical agent that could effect both of these causative factors. Specifically, a topical preparation consisting of an anti-estrogen and a vascular endothelial growth factor inhibitor would accomplish this goal. Suitable candidates that target estrogen receptors and vascular endothelial growth factor are currently used in medical oncology as systemic antineoplastic agents. The anti-estrogen could be either a selective estrogen receptor modulator (such as tamoxifen or raloxifene) or an aromatase inhibitor (such as anastrozole or letrozole or exemestane). The vascular endothelial growth factor inhibitor would be bevacizumab. In conclusion, a novel-topically administered-therapy for melasma would combine an anti-estrogen and a vascular endothelial growth factor inhibitor. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Effects of basic fibroblast growth factor and insulin-like growth factor on cultured cartilage cells from skate Raja porasa

    NASA Astrophysics Data System (ADS)

    Fan, Tingjun; Jin, Lingyun; Wang, Xiaofeng

    2003-12-01

    Effects of basic fibroblast growth factor (bFGF) and insulin-like growth factor II (IGF-II) on cartilage cells from proboscis of skate, Raja porasa Günther, were investigated in this study. The cartilage cells were cultured in 20% FBS-supplemented MEM medium at 24°C. Twelve hours after culture initiation, the cartilage cells were treated with bFGF and IGF-II at different concentration combinations. It was found that 20 ng/ml of bFGF or 80 ng/ml of IGF-II was enough to have obvious stimulating effect on the growth and division of skate cartilage cells. Test of bFGF and IGF-II together, revealed that 20 ng/ml of bFGF and 80 ng/ml of IGF-II together had the best stimulating effect on the growth and division of skate cartilage cells. The cartilage cells cultured could form a monolayer at day 7.

  2. Fibroblast Growth Factor 2: An Epithelial Ductal Cell Growth Inhibitor That Drops Out in Breast Cancer

    DTIC Science & Technology

    2010-10-01

    AD_________________ Award Number: W81XWH-08-1-0708 TITLE: Fibroblast Growth Factor 2: an...September 2009 – 14 September 2010 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Fibroblast Growth Factor 2: an Epithelial Ductal Cell Growth ...8 Appendices…………………………………………………………………………… 8 Supporting Data……………………………………………………………………... 8 Fibroblast Growth Factor -2: an

  3. Role of G protein-coupled estrogen receptor-1, matrix metalloproteinases 2 and 9, and heparin binding epidermal growth factor-like growth factor in estradiol-17β-stimulated bovine satellite cell proliferation.

    PubMed

    Kamanga-Sollo, E; Thornton, K J; White, M E; Dayton, W R

    2014-10-01

    In feedlot steers, estradiol-17β (E2) and combined E2 and trenbolone acetate (a testosterone analog) implants enhance rate and efficiency of muscle growth; and, consequently, these compounds are widely used as growth promoters. Although the positive effects of E2 on rate and efficiency of bovine muscle growth are well established, the mechanisms involved in these effects are not well understood. Combined E2 and trenbolone acetate implants result in significantly increased muscle satellite cell number in feedlot steers. Additionally, E2 treatment stimulates proliferation of cultured bovine satellite cells (BSC). Studies in nonmuscle cells have shown that binding of E2 to G protein-coupled estrogen receptor (GPER)-1 results in activation of matrix metalloproteinases 2 and 9 (MMP2/9) resulting in proteolytic release of heparin binding epidermal growth factor-like growth factor (hbEGF) from the cell surface. Released hbEGF binds to and activates the epidermal growth factor receptor resulting in increased proliferation. To assess if GPER-1, MMP2/9, and/or hbEGF are involved in the mechanism of E2-stimulated BSC proliferation, we have examined the effects of G36 (a specific inhibitor of GPER-1), CRM197 (a specific inhibitor of hbEGF), and MMP-2/MMP-9 Inhibitor II (an inhibitor of MMP2/9 activity) on E2-stimulated BSC proliferation. Inhibition of GPER-1, MMP2/9, or hbEGF suppresses E2-stimulated BSC proliferation (P < 0.001) suggesting that all these are required in order for E2 to stimulate BSC proliferation. These results strongly suggest that E2 may stimulate BSC proliferation by binding to GPER-1 resulting in MMP2/9-catalyzed release of cell membrane-bound hbEGF and subsequent activation of epidermal growth factor receptor by binding of released hbEGF. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Insulin-Like Growth Factor Receptor Signaling is Necessary for Epidermal Growth Factor Mediated Proliferation of SVZ Neural Precursors in vitro Following Neonatal Hypoxia–Ischemia

    PubMed Central

    Alagappan, Dhivyaa; Ziegler, Amber N.; Chidambaram, Shravanthi; Min, Jungsoo; Wood, Teresa L.; Levison, Steven W.

    2014-01-01

    In this study, we assessed the importance of insulin-like growth factor (IGF) and epidermal growth factor (EGF) receptor co-signaling for rat neural precursor (NP) cell proliferation and self-renewal in the context of a developmental brain injury that is associated with cerebral palsy. Consistent with previous studies, we found that there is an increase in the in vitro growth of subventricular zone NPs isolated acutely after cerebral hypoxia–ischemia; however, when cultured in medium that is insufficient to stimulate the IGF type 1 receptor, neurosphere formation and the proliferative capacity of those NPs was severely curtailed. This reduced growth capacity could not be attributed simply to failure to survive. The growth and self-renewal of the NPs could be restored by addition of both IGF-I and IGF-II. Since the size of the neurosphere is predominantly due to cell proliferation we hypothesized that the IGFs were regulating progression through the cell cycle. Analyses of cell cycle progression revealed that IGF-1R activation together with EGFR co-signaling decreased the percentage of cells in G1 and enhanced cell progression into S and G2. This was accompanied by increases in expression of cyclin D1, phosphorylated histone 3, and phosphorylated Rb. Based on these data, we conclude that coordinate signaling between the EGF receptor and the IGF type 1 receptor is necessary for the normal proliferation of NPs as well as for their reactive expansion after injury. These data indicate that manipulations that maintain or amplify IGF signaling in the brain during recovery from developmental brain injuries will enhance the production of new brain cells to improve neurological function in children who are at risk for developing cerebral palsy. PMID:24904523

  5. Platelet-derived growth factor inhibits platelet activation in heparinized whole blood.

    PubMed

    Selheim, F; Holmsen, H; Vassbotn, F S

    1999-08-15

    We previously have demonstrated that human platelets have functionally active platelet-derived growth factor alpha-receptors. Studies with gel-filtered platelets showed that an autocrine inhibition pathway is transduced through this tyrosine kinase receptor during platelet activation. The physiological significance of this inhibitory effect of platelet-derived growth factor on gel-filtered platelets activation is, however, not known. In the present study, we investigated whether platelet-derived growth factor inhibits platelet activation under more physiological conditions in heparinized whole blood, which represents a more physiological condition than gel-filtered platelets. Using flow cytometric assays, we demonstrate here that platelet-derived growth factor inhibits thrombin-, thrombin receptor agonist peptide SFLLRN-, and collagen-induced platelet aggregation and shedding of platelet-derived microparticles from the platelet plasma membrane during platelet aggregation in stirred heparinized whole blood. The inhibitory effect of platelet-derived growth factor was dose dependent. However, under nonaggregating conditions (no stirring), we could not demonstrate any significant effect of platelet-derived growth factor on thrombin- and thrombin receptor agonist peptide-induced platelet surface expression of P-selectin. Our results demonstrate that platelet-derived growth factor appears to be a true antithrombotic agent only under aggregating conditions in heparinized whole blood.

  6. Immobilization of Growth Factors to Collagen Surfaces Using Pulsed Visible Light.

    PubMed

    Fernandes-Cunha, Gabriella M; Lee, Hyun Jong; Kumar, Alisha; Kreymerman, Alexander; Heilshorn, Sarah; Myung, David

    2017-10-09

    In the treatment of traumatic injuries, burns, and ulcers of the eye, inadequate epithelial tissue healing remains a major challenge. Wound healing is a complex process involving the temporal and spatial interplay between cells and their extracellular milieu. It can be impaired by a variety of causes including infection, poor circulation, loss of critical cells, and/or proteins, and a deficiency in normal neural signaling (e.g., neurotrophic ulcers). Ocular anatomy is particularly vulnerable to lasting morbidity from delayed healing, whether it be scarring or perforation of the cornea, destruction of the conjunctival mucous membrane, or cicatricial changes to the eyelids and surrounding skin. Therefore, there is a major clinical need for new modalities for controlling and accelerating wound healing, particularly in the eye. Collagen matrices have long been explored as scaffolds to support cell growth as both two-dimensional coatings and substrates, as well as three-dimensional matrices. Meanwhile, the immobilization of growth factors to various substrates has also been extensively studied as a way to promote enhanced cellular adhesion and proliferation. Herein we present a new strategy for photochemically immobilizing growth factors to collagen using riboflavin as a photosensitizer and exposure to visible light (∼458 nm). Epidermal growth factor (EGF) was successfully bound to collagen-coated surfaces as well as directly to endogenous collagen from porcine corneas. The initial concentration of riboflavin and EGF as well as the blue light exposure time were keys to the successful binding of growth factors to these surfaces. The photocrosslinking reaction increased EGF residence time on collagen surfaces over 7 days. EGF activity was maintained after the photocrosslinking reaction with a short duration of pulsed blue light exposure. Bound EGF accelerated in vitro corneal epithelial cell proliferation and migration and maintained normal cell phenotype. Additionally

  7. Gelatin Methacrylate Microspheres for Growth Factor Controlled Release

    PubMed Central

    Nguyen, Anh H.; McKinney, Jay; Miller, Tobias; Bongiorno, Tom; McDevitt, Todd C.

    2014-01-01

    Gelatin has been commonly used as a delivery vehicle for various biomolecules for tissue engineering and regenerative medicine applications due to its simple fabrication methods, inherent electrostatic binding properties, and proteolytic degradability. Compared to traditional chemical cross-linking methods, such as the use of glutaraldehyde (GA), methacrylate modification of gelatin offers an alternative method to better control the extent of hydrogel cross-linking. Here we examined the physical properties and growth factor delivery of gelatin methacrylate (GMA) microparticles formulated with a wide range of different cross-linking densities (15–90%). Less methacrylated MPs had decreased elastic moduli and larger mesh sizes compared to GA MPs, with increasing methacrylation correlating to greater moduli and smaller mesh sizes. As expected, an inverse correlation between microparticle cross-linking density and degradation was observed, with the lowest cross-linked GMA MPs degrading at the fastest rate, comparable to GA MPs. Interestingly, GMA MPs at lower cross-linking densities could be loaded with up to a 10-fold higher relative amount of growth factor over conventional GA cross-linked MPs, despite an order of magnitude greater gelatin content of GA MPs. Moreover, a reduced GMA cross-linking density resulted in more complete release of bone morphogenic protein 4 (BMP4) and basic fibroblast growth factor (bFGF) and accelerated release rate with collagenase treatment. These studies demonstrate that GMA MPs provide a more flexible platform for growth factor delivery by enhancing the relative binding capacity and permitting proteolytic degradation tunability, thereby offering a more potent controlled release system for growth factor delivery. PMID:25463489

  8. Quinones are growth factors for the human gut microbiota.

    PubMed

    Fenn, Kathrin; Strandwitz, Philip; Stewart, Eric J; Dimise, Eric; Rubin, Sarah; Gurubacharya, Shreya; Clardy, Jon; Lewis, Kim

    2017-12-20

    The human gut microbiome has been linked to numerous components of health and disease. However, approximately 25% of the bacterial species in the gut remain uncultured, which limits our ability to properly understand, and exploit, the human microbiome. Previously, we found that growing environmental bacteria in situ in a diffusion chamber enables growth of uncultured species, suggesting the existence of growth factors in the natural environment not found in traditional cultivation media. One source of growth factors proved to be neighboring bacteria, and by using co-culture, we isolated previously uncultured organisms from the marine environment and identified siderophores as a major class of bacterial growth factors. Here, we employ similar co-culture techniques to grow bacteria from the human gut microbiome and identify novel growth factors. By testing dependence of slow-growing colonies on faster-growing neighboring bacteria in a co-culture assay, eight taxonomically diverse pairs of bacteria were identified, in which an "induced" isolate formed a gradient of growth around a cultivatable "helper." This set included two novel species Faecalibacterium sp. KLE1255-belonging to the anti-inflammatory Faecalibacterium genus-and Sutterella sp. KLE1607. While multiple helper strains were identified, Escherichia coli was also capable of promoting growth of all induced isolates. Screening a knockout library of E. coli showed that a menaquinone biosynthesis pathway was required for growth induction of Faecalibacterium sp. KLE1255 and other induced isolates. Purified menaquinones induced growth of 7/8 of the isolated strains, quinone specificity profiles for individual bacteria were identified, and genome analysis suggests an incomplete menaquinone biosynthetic capability yet the presence of anaerobic terminal reductases in the induced strains, indicating an ability to respire anaerobically. Our data show that menaquinones are a major class of growth factors for bacteria

  9. Human Herpesvirus-8-Transformed Endothelial Cells Have Functionally Activated Vascular Endothelial Growth Factor/Vascular Endothelial Growth Factor Receptor

    PubMed Central

    Masood, Rizwan; Cesarman, Ethel; Smith, D. Lynne; Gill, Parkash S.; Flore, Ornella

    2002-01-01

    Kaposi’s sarcoma is a vascular tumor commonly associated with human immunodeficiency virus (HIV)-1 and human herpesvirus (HHV-8) also known as Kaposi’s sarcoma-associated herpesvirus. The principal features of this tumor are abnormal proliferation of vascular structures lined with spindle-shaped endothelial cells. HHV-8 may transform a subpopulation of endothelial cells in vitro via viral and cellular gene expression. We hypothesized that among the cellular genes, vascular endothelial growth factors (VEGFs) and their cognate receptors may be involved in viral-mediated transformation. We have shown that HHV-8-transformed endothelial cells (EC-HHV-8) express higher levels of VEGF, VEGF-C, VEGF-D, and PlGF in addition to VEGF receptors-1, -2, and -3. Furthermore, antibodies to VEGF receptor-2 inhibited cell proliferation and viability. Similarly, inhibition of VEGF gene expression with antisense oligonucleotides inhibited EC-HHV-8 cell proliferation/viability. The growth and viability of primary endothelial cells and a fibroblast cell line however were unaffected by either the VEGF receptor-2 antibody or the VEGF antisense oligodeoxynucleotides. VEGF and VEGF receptors are thus induced in EC-HHV-8 and participate in the transformation. Inhibitors of VEGF may thus modulate the disease process during development and progression. PMID:11786394

  10. Therapeutic modulation of growth factors and cytokines in regenerative medicine.

    PubMed

    Ioannidou, Effie

    2006-01-01

    Regeneration that takes place in the human body is limited throughout life. Therefore, when organs are irreparably damaged, they are usually replaced with an artificial device or donor organ. The term "regenerative medicine" covers the restoration or replacement of cells, tissues, and organs. Stem cells play a major role in regenerative medicine by providing the way to repopulate organs damaged by disease. Stem cells have the ability to self renew and to regenerate cells of diverse lineages within the tissue in which they reside. Stem cells could originate from embryos or adult tissues. Growth factors are proteins that may act locally or systemically to affect the growth of cells in several ways. Various cell activities, including division, are influenced by growth factors. Cytokines are a family of low-molecular-weight proteins that are produced by numerous cell types and are responsible for regulating the immune response, inflammation, tissue remodeling and cellular differentiation. Target cells of growth factors and cytokines are mesenchymal, epithelial and endothelial cells. These molecules frequently have overlapping activities and can act in an autocrine or paracrine fashion. A complex network of growth factors and cytokines guides cellular differentiation and regeneration in all organs and tissues. The aim of this paper is to review the role of growth factors and cytokines in different organs or systems and explore their therapeutic application in regenerative medicine. The role of stem cells combined with growth factors and cytokines in the regeneration of vascular and hematopoietic, neural, skeletal, pancreatic, periodontal, and mucosal tissue is reviewed. There is evidence that supports the use of growth factors and cytokines in the treatment of neurological diseases, diabetes, cardiovascular disease, periodontal disease, cancer and its complication, oral mucositis. After solving the ethical issues and establishing clear and reasonable regulations

  11. [Effect of cryotherapy over the expression of vascular endothelial growth factor and pigment epithelium-derived factor].

    PubMed

    Toscano-Garibay, Julia Dolores; Quiroz-Mercado, Hugo; Espitia-Pinzón, Clara; Gil-Carrasco, Félix; Flores-Estrada, José Javier

    2014-01-01

    Cryotherapy is a no invasive technique that uses intense cold to freeze and destroy cancer tissues. There are no descriptions of its effects over the expression of vascular endothelial growth factor and pigment epithelium-derived factor. Experimental study in cryogenic spot were applied in the right sclera of twelve pigs for ten minutes. Other 3 pigs were used as normal controls. Animals were sacrificed at 7, 14 and 21 and the tissues of choriodes and retina were dissected in areas of approximately 1 cm2 surrounding cryogenic spots. Expression levels of vascular endothelial growth factor and pigment epithelium-derived factor were determined analyzed using polymerase chain reaction coupled to reverse-transcription. Vascular endothelial growth factor was significantly downregulated (24%, p< 0.05) seven days post-treatment meanwhile pigment epithelium-derived factor levels increased 44.8% (p< 0.05) as compared to normal controls (untreated). Both vascular endothelial growth factor and pigment epithelium-derived factor levels remain the same until day 14 but returned to basal expression at day 21. This work expose the relation of cryotherapy with the expression of two factors related to angiogenesis. RESULTS showed significant changes on the expression of vascular endothelial growth factor and pigment epithelium-derived factor illustrating that both proteins are regulated in response to cryogenic treatment in relatively short periods (21 days).

  12. EGFR ligands drive multipotential stromal cells to produce multiple growth factors and cytokines via early growth response-1.

    PubMed

    Kerpedjieva, Svetoslava S; Kim, Duk Soo; Barbeau, Dominique J; Tamama, Kenichi

    2012-09-01

    Cell therapy with adult bone marrow multipotential stromal cells/mesenchymal stem cells (MSCs) presents a promising approach to promote wound healing and tissue regeneration. The strong paracrine capability of various growth factors and cytokines is a key mechanism of MSC-mediated wound healing and tissue regeneration, and the goal of this study is to understand the underlying mechanism that supports the strong paracrine machineries in MSCs. Microarray database analyses revealed that early growth response-1 (EGR1) is highly expressed in MSCs. Our previous studies showed that epidermal growth factor (EGF) treatment induces growth factor production in MSCs in vitro. Since EGF strongly upregulates EGR1, we hypothesized that EGF receptor (EGFR)-EGR1 signaling plays a pivotal role in MSC paracrine activity. EGF treatment upregulated the gene expression of growth factors and cytokines, including EGFR ligands in a protein kinase C (PKC)- and/or mitogen-activated protein kinase-extracellular-signal-regulated kinase-dependent manner, and it was reversed by shRNA against EGR1. PKC activator phorbol 12-myristate 13-acetate enhanced EGFR tyrosyl phosphorylation and upregulated the gene expression of growth factors and cytokines in a heparin-binding EGF-like growth factor (HBEGF) inhibitor CRM197 sensitive manner, indicating an involvement of autocrined HBEGF in the downstream of PKC signaling. Moreover, stimulation with growth factors and cytokines induced the expression of EGFR ligands, presumably via EGR1 upregulation. These data indicate EGR1 as a convergence point of multiple signaling pathways, which in turn augments the production of multiple growth factors and cytokines by enhancing the autocrine signaling with EGFR ligands.

  13. Keratinocyte growth factor is a growth factor for mammary epithelium in vivo. The mammary epithelium of lactating rats is resistant to the proliferative action of keratinocyte growth factor.

    PubMed Central

    Ulich, T. R.; Yi, E. S.; Cardiff, R.; Yin, S.; Bikhazi, N.; Biltz, R.; Morris, C. F.; Pierce, G. F.

    1994-01-01

    Keratinocyte growth factor (KGF) is a member of the fibroblast growth factor (FGF) family. KGF is secreted by stromal cells and affects epithelial but not mesenchymal cell proliferation. KGF injected intravenously was found to cause dramatic proliferation of mammary epithelium in the mammary glands of rats. KGF causes ductal neogenesis and intraductal epithelial hyperplasia but not lobular differentiation in nulliparous female rats. KGF causes ductal and lobular epithelial hyperplasia in male rats. KGF causes proliferation of ductal and acinar cells in the mammary glands of pregnant rats. On the other hand, the ductal epithelium of lactating postpartum rats is resistant to the proliferative action of KGF. The mammary glands of lactating rats did not express less KGF receptor mRNA than the glands of pregnant rats, suggesting that the resistance of the ductal epithelium to KGF during lactation is not related to KGF receptor mRNA down-regulation. The mammary glands of both pregnant and postpartum lactating rats express KGF mRNA with more KGF present in the glands of lactating rats. In conclusion, the KGF and KGF receptor genes are expressed in rat mammary glands and recombinant KGF is a potent growth factor for mammary epithelium. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8178937

  14. Cloning of a cancer cell-producing hepatocyte growth factor, vascular endothelial growth factor, and interleukin-8 from gastric cancer cells.

    PubMed

    Iwai, Mineko; Matsuda, Masahiko; Iwai, Yoshiaki

    2003-01-01

    A cell colony (IM95m) that produces hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), and interleukin-8 (IL-8) was cloned from gastric cancer cells (IM95 cell line). In culture medium, the highest levels of HGF, VEGF, and IL-8 were about 1.1, 0.9, and 0.17 ng/ml culture medium at 3 d from 10(5) cells. IM95m may be useful in elucidating the role of tumor cells in angiogenesis.

  15. [Insulin-like growth factor-1 (IGF-1) - structure and the role in the human body].

    PubMed

    Filus, Alicja; Zdrojewicz, Zygmunt

    2015-01-01

    In the recent years, managed to broadly explore the structure and role of insulin-like growth factors type 1 and 2 (IGF1 I 2). They belong to the structure of polypeptide hormones homologous to proinsulin. They are characterized by a wide range of activities. IGF-1 is a key mediator of most tissue effects of growth hormone (GH). In addition to effects on growth processes of the body, is also an important factor for cell homeostasis, is subject to both endocrine and tissue-specific auto- and paracrine regulation. In this paper, the current, general knowledge on the structure, function and mechanism of biological effects of IGF-1 in the human body was presented. Attention was also drawn to the directions of use of IGf-1 in the treatment of other diseases than the diseases of the hypothalamic-pituitary and growth disorders in children. © Polish Society for Pediatric Endocrinology and Diabetology.

  16. The cell-penetrating peptide domain from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) has anti-inflammatory activity in vitro and in vivo.

    PubMed

    Lee, Jue-Yeon; Seo, Yoo-Na; Park, Hyun-Jung; Park, Yoon-Jeong; Chung, Chong-Pyoung

    2012-03-23

    A heparin-binding peptide (HBP) sequence from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) was identified and was shown to exhibit cell penetration activity. This cell penetration induced an anti-inflammatory reaction in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. HBP penetrated the cell membrane during the 10 min treatment and reduced the LPS-induced production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), and cytokines (TNF-α and IL-6) in a concentration-dependent manner. Additionally, HBP inhibited the LPS-induced upregulation of cytokines, including TNF-α and IL-6, and decreased the interstitial infiltration of polymorphonuclear leukocytes in a lung inflammation model. HBP inhibited NF-κB-dependent inflammatory responses by directly blocking the phosphorylation and degradation of IκBα and by subsequently inhibiting the nuclear translocation of the p65 subunit of NF-κB. Taken together, this novel HBP may be potentially useful candidate for anti-inflammatory treatments and can be combined with other drugs of interest to transport attached molecules into cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Role of G protein-coupled receptors (GPCR), matrix metalloproteinases 2 and 9 (MMP2 and MMP9), heparin-binding epidermal growth factor-like growth factor (hbEGF), epidermal growth factor receptor (EGFR), erbB2, and insulin-like growth factor 1 receptor (IGF-1R) in trenbolone acetate-stimulated bovine satellite cell proliferation.

    PubMed

    Thornton, K J; Kamange-Sollo, E; White, M E; Dayton, W R

    2015-09-01

    Implanting cattle with steroids significantly enhances feed efficiency, rate of gain, and muscle growth. However, the mechanisms responsible for these improvements in muscle growth have not been fully elucidated. Trenbolone acetate (TBA), a testosterone analog, has been shown to increase proliferation rate in bovine satellite cell (BSC) cultures. The classical genomic actions of testosterone have been well characterized; however, our results indicate that TBA may also initiate a quicker, nongenomic response that involves activation of G protein-coupled receptors (GPCR) resulting in activation of matrix metalloproteinases 2 and 9 (MMP2 and MMP9) that release membrane-bound heparin-binding epidermal growth factor-like growth factor (hbEGF), which then binds to and activates the epidermal growth factor receptor (EGFR) and/or erbB2. Furthermore, the EGFR has been shown to regulate expression of the IGF-1 receptor (IGF-1R), which is well known for its role in modulating muscle growth. To determine whether this nongenomic pathway is potentially involved in TBA-stimulated BSC proliferation, we analyzed the effects of treating BSC with guanosine 5'-O-2-thiodiphosphate (GDPβS), an inhibitor of all GPCR; a MMP2 and MMP9 inhibitor (MMPI); CRM19, a specific inhibitor of hbEGF; AG1478, a specific EGFR tyrosine kinase inhibitor; AG879, a specific erbB2 kinase inhibitor; and AG1024, an IGF-1R tyrosine kinase inhibitor on TBA-stimulated proliferation rate (H-thymidine incorporation). Assays were replicated at least 9 times for each inhibitor experiment using BSC cultures obtained from at least 3 different animals. Bovine satellite cell cultures were obtained from yearling steers that had no previous exposure to androgenic or estrogenic compounds. As expected, BSC cultures treated with 10 n TBA showed ( < 0.05) increased proliferation rate when compared with control cultures. Additionally, treatment with 5 ng hbEGF/mL stimulated proliferation in BSC cultures ( < 0.05). Treatment

  18. Impaired growth in Rabson-Mendenhall syndrome: lack of effect of growth hormone and insulin-like growth factor-I.

    PubMed

    Longo, N; Singh, R; Griffin, L D; Langley, S D; Parks, J S; Elsas, L J

    1994-09-01

    Mutations in the insulin receptor gene cause the severe insulin-resistant syndromes leprechaunism and Rabson-Mendenhall syndrome. There is no accepted therapy for these inherited conditions. Here we report the results of recombinant human GH (rhGH) and recombinant human insulin-like growth factor-I (rhIGF-I) treatment of a male patient, Atl-2, with Rabson-Mendenhall syndrome. The patient was small for gestational age, had premature dentition, absence of sc fat, acanthosis nigricans, fasting hypoglycemia and postprandial hyperglycemia, and extremely high concentrations of circulating insulin (up to 8500 microU/mL). Fibroblasts and lymphoblasts established from this patient had reduced insulin binding, which was 20-30% of the control value. Binding of epidermal growth factor, IGF-I, and GH to the patient's fibroblasts was normal. The growth of fibroblasts cultured from patient Atl-2 in vitro was intermediate between that of fibroblasts from patients with leprechaunism and control values. The patient's growth curve in vivo was far below the fifth percentile despite adequate nutrition. To stimulate growth, therapy with rhGH was initiated, the rationale being to stimulate hepatic IGF-I production and IGF-I receptor signaling, and bypass the inherited block in insulin receptor signaling. Therapy with rhGH (up to 0.5 mg/kg.week) did not improve growth and failed to increase the levels of circulating IGF-I and IGF-binding protein-3 over a 14-month period. As rhGH could not stimulate growth, rhIGF-I (up to 100 micrograms/kg.day) was given by daily sc injection. No increase in growth velocity was observed over a 14-month period. These results indicate that both GH and IGF-I fail to correct growth in a patient with severe inherited insulin resistance. The lack of efficacy of IGF-I treatment may be related to multiple factors, such as the poor metabolic state of the patient, the deficiency of serum carrier protein for IGF-I, an increased clearance of the growth factor, IGF

  19. Targeting Insulin-Like Growth Factor 1 Receptor Inhibits Pancreatic Cancer Growth and Metastasis

    PubMed Central

    Subramani, Ramadevi; Lopez-Valdez, Rebecca; Arumugam, Arunkumar; Nandy, Sushmita; Boopalan, Thiyagarajan; Lakshmanaswamy, Rajkumar

    2014-01-01

    Pancreatic cancer is one of the most lethal cancers. Increasing incidence and mortality indicates that there is still much lacking in detection and management of the disease. This is partly due to a lack of specific symptoms during early stages of the disease. Several growth factor receptors have been associated with pancreatic cancer. Here, we have investigated if an RNA interference approach targeted to IGF-IR could be effective and efficient against pancreatic cancer growth and metastasis. For that, we evaluated the effects of IGF-1R inhibition using small interfering RNA (siRNAs) on tumor growth and metastasis in HPAC and PANC-1 pancreatic cancer cell lines. We found that silencing IGF-1R inhibits pancreatic cancer growth and metastasis by blocking key signaling pathways such AKT/PI3K, MAPK, JAK/STAT and EMT. Silencing IGF-1R resulted in an anti-proliferative effect in PANC-1 and HPAC pancreatic cancer cell lines. Matrigel invasion, transwell migration and wound healing assays also revealed a role for IGF-1R in metastatic properties of pancreatic cancer. These results were further confirmed using Western blotting analysis of key intermediates involved in proliferation, epithelial mesenchymal transition, migration, and invasion. In addition, soft agar assays showed that silencing IGF-1R also blocks the colony forming capabilities of pancreatic cancer cells in vitro. Western blots, as well as, flow cytometric analysis revealed the induction of apoptosis in IGF-1R silenced cells. Interestingly, silencing IGF-1R also suppressed the expression of insulin receptor β. All these effects together significantly control pancreatic cancer cell growth and metastasis. To conclude, our results demonstrate the significance of IGF-1R in pancreatic cancer. PMID:24809702

  20. Bone marrow hematopoietic stem cells behavior with or without growth factors in trauma hemorrhagic shock

    PubMed Central

    Kumar, Manoj; Bhoi, Sanjeev; Mohanty, Sujata; Kamal, Vineet Kumar; Rao, D. N.; Mishra, Pravas; Galwankar, Sagar

    2016-01-01

    Background: Hemorrhagic shock (HS) is the major leading cause of death after trauma. Up to 50% of early deaths are due to massive hemorrhage. Excessive release of pro-inflammatory cytokine and hypercatecholamine induces hematopoietic progenitor cells (HPCs) apoptosis, leading to multiorgan failure and death. However, still, result remains elusive for hematopoietic stem cells (HSCs) behavior in trauma HS (T/HS). Objectives: Therefore, our aim was to evaluate the in vitro HSCs behavior with or without recombinant human erythropoietin (rhEPO), recombinant human granulocyte macrophage-colony-stimulating factor (rhGM-CSF), recombinant human interleukin-3 (rhIL-3) alone, and combination with rhEPO + rhGM-CSF + rhIL-3 (EG3) in T/HS patients. Methodology: Bone marrow (BM) aspirates (n = 14) were collected from T/HS patients, those survived on day 3. BM cells were cultured for HPCs: Colony-forming unit-erythroid (CFU-E), burst-forming unit-erythroid (BFU-E), and colony-forming unit-granulocyte, monocyte/macrophage colonies growth. HPCs were counted with or without rhEPO, rhGM-CSF, rhIL-3 alone, and combination with EG3 in T/HS patients. Results: BM HSCs growth significantly suppressed in T/HS when compared with control group (P < 0.05). In addition, CFU-E and BFU-E colony growth were increased with additional growth factor (AGF) (rhEPO, rhGM-CSF, and rhIL-3) as compared to baseline (without AGF) (P < 0.05). Conclusion: Suppressed HPCs may be reactivated by addition of erythropoietin, GM-CSF, IL-3 alone and with combination in T/HS. PMID:27722113

  1. Arctigenin induced gallbladder cancer senescence through modulating epidermal growth factor receptor pathway.

    PubMed

    Zhang, Mingdi; Cai, Shizhong; Zuo, Bin; Gong, Wei; Tang, Zhaohui; Zhou, Di; Weng, Mingzhe; Qin, Yiyu; Wang, Shouhua; Liu, Jun; Ma, Fei; Quan, Zhiwei

    2017-05-01

    Gallbladder cancer has poor prognosis and limited therapeutic options. Arctigenin, a representative dibenzylbutyrolactone lignan, occurs in a variety of plants. However, the molecular mechanisms involved in the antitumor effect of arctigenin on gallbladder cancer have not been fully elucidated. The expression levels of epidermal growth factor receptor were examined in 100 matched pairs of gallbladder cancer tissues. A positive correlation between high epidermal growth factor receptor expression levels and poor prognosis was observed in gallbladder cancer tissues. Pharmacological inhibition or inhibition via RNA interference of epidermal growth factor receptor induced cellular senescence in gallbladder cancer cells. The antitumor effect of arctigenin on gallbladder cancer cells was primarily achieved by inducing cellular senescence. In gallbladder cancer cells treated with arctigenin, the expression level of epidermal growth factor receptor significantly decreased. The analysis of the activity of the kinases downstream of epidermal growth factor receptor revealed that the RAF-MEK-ERK signaling pathway was significantly inhibited. Furthermore, the cellular senescence induced by arctigenin could be reverted by pcDNA-epidermal growth factor receptor. Arctigenin also potently inhibited the growth of tumor xenografts, which was accompanied by the downregulation of epidermal growth factor receptor and induction of senescence. This study demonstrates arctigenin could induce cellular senescence in gallbladder cancer through the modulation of epidermal growth factor receptor pathway. These data identify epidermal growth factor receptor as a key regulator in arctigenin-induced gallbladder cancer senescence.

  2. Redox-regulated growth factor survival signaling.

    PubMed

    Woolley, John F; Corcoran, Aoife; Groeger, Gillian; Landry, William D; Cotter, Thomas G

    2013-11-20

    Once the thought of as unwanted byproducts of cellular respiration in eukaryotes, reactive oxygen species (ROS) have been shown to facilitate essential physiological roles. It is now understood that ROS are critical mediators of intracellular signaling. Control of signal transduction downstream of growth factor receptors by ROS is a complex process whose details are only recently coming to light. Indeed, recent evidence points to control of signal propagation by ROS at multiple levels in the typical cascade. Growth factor stimulation activates nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Noxs) at the membrane, producing superoxide in the extracellular matrix, which is catalyzed to the membrane-permeable hydrogen peroxide (H2O2) that mediates intracellular signaling events. The potential for H2O2, however, to disrupt cellular functions by damaging proteins and nucleic acids demands that its levels are kept in check by receptor-associated peroxiredoxins. This interplay of Nox and peroxiredoxin activity moderates levels of H2O2 sufficiently to modify signaling partners locally. Among the best studied of these partners are redox-controlled phosphatases that are inactivated by H2O2. Phosphatases regulate signal propagation downstream of receptors, and thus their inactivation allows a further level of control. Transmission of information further downstream to targets such as transcription factors, themselves regulated by ROS, completes this pathway. Thus, signal propagation or attenuation can be dictated by ROS at multiple points. Given the complex nature of these processes, we envisage the emerging trends in the field of redox signaling in the context of growth factor stimulation.

  3. Endosomal receptor kinetics determine the stability of intracellular growth factor signalling complexes

    PubMed Central

    Tzafriri, A. Rami; Edelman, Elazer R.

    2006-01-01

    There is an emerging paradigm that growth factor signalling continues in the endosome and that cell response to a growth factor is defined by the integration of cell surface and endosomal events. As activated receptors in the endosome are exposed to a different set of binding partners, they probably elicit differential signals compared with when they are at the cell surface. As such, complete appreciation of growth factor signalling requires understanding of growth factor–receptor binding and trafficking kinetics both at the cell surface and in endosomes. Growth factor binding to surface receptors is well characterized, and endosomal binding is assumed to follow surface kinetics if one accounts for changes in pH. Yet, specific binding kinetics within the endosome has not been examined in detail. To parse the factors governing the binding state of endosomal receptors we analysed a whole-cell mathematical model of epidermal growth factor receptor trafficking and binding. We discovered that the stability of growth factor–receptor complexes within endosomes is governed by three primary independent factors: the endosomal dissociation constant, total endosomal volume and the number of endosomal receptors. These factors were combined into a single dimensionless parameter that determines the endosomal binding state of the growth factor–receptor complex and can distinguish different growth factors from each other and different cell states. Our findings indicate that growth factor binding within endosomal compartments cannot be appreciated solely on the basis of the pH-dependence of the dissociation constant and that the concentration of receptors in the endosomal compartment must also be considered. PMID:17117924

  4. EGFR Ligands Drive Multipotential Stromal Cells to Produce Multiple Growth Factors and Cytokines via Early Growth Response-1

    PubMed Central

    Kerpedjieva, Svetoslava S.; Kim, Duk Soo; Barbeau, Dominique J.

    2012-01-01

    Cell therapy with adult bone marrow multipotential stromal cells/mesenchymal stem cells (MSCs) presents a promising approach to promote wound healing and tissue regeneration. The strong paracrine capability of various growth factors and cytokines is a key mechanism of MSC-mediated wound healing and tissue regeneration, and the goal of this study is to understand the underlying mechanism that supports the strong paracrine machineries in MSCs. Microarray database analyses revealed that early growth response-1 (EGR1) is highly expressed in MSCs. Our previous studies showed that epidermal growth factor (EGF) treatment induces growth factor production in MSCs in vitro. Since EGF strongly upregulates EGR1, we hypothesized that EGF receptor (EGFR)–EGR1 signaling plays a pivotal role in MSC paracrine activity. EGF treatment upregulated the gene expression of growth factors and cytokines, including EGFR ligands in a protein kinase C (PKC)- and/or mitogen-activated protein kinase–extracellular-signal-regulated kinase-dependent manner, and it was reversed by shRNA against EGR1. PKC activator phorbol 12-myristate 13-acetate enhanced EGFR tyrosyl phosphorylation and upregulated the gene expression of growth factors and cytokines in a heparin-binding EGF-like growth factor (HBEGF) inhibitor CRM197 sensitive manner, indicating an involvement of autocrined HBEGF in the downstream of PKC signaling. Moreover, stimulation with growth factors and cytokines induced the expression of EGFR ligands, presumably via EGR1 upregulation. These data indicate EGR1 as a convergence point of multiple signaling pathways, which in turn augments the production of multiple growth factors and cytokines by enhancing the autocrine signaling with EGFR ligands. PMID:22316125

  5. Isolation of a cDNA for a Growth Factor of Vascular Endothelial Cells from Human Lung Cancer Cells: Its Identity with Insulin‐like Growth Factor II

    PubMed Central

    Hagiwara, Koichi; Kobayashi, Tatsuo; Tobita, Masato; Kikyo, Nobuaki; Yazaki, Yoshio

    1995-01-01

    We have found growth‐promoting activity for vascular endothelial cells in the conditioned medium of a human lung cancer cell line, T3M‐11. Purification and characterization of the growth‐promoting activity have been carried out using ammonium sulfate precipitation and gel‐exclusion chromatography. The activity migrated as a single peak just after ribonuclease. It did not bind to a heparin affinity column. These results suggest that the activity is not a heparin‐binding growth factor (including fibroblast growth factors) or a vascular endothelial growth factor. To identify the molecule exhibiting the growth‐promoting activity, a cDNA encoding the growth factor was isolated through functional expression cloning in COS‐1 cells from a cDNA library prepared from T3M‐11 cells. The nucleotide sequence encoded by the cDNA proved to be identical with that of insulin‐like growth factor II. PMID:7730145

  6. Normal growth and development in the absence of hepatic insulin-like growth factor I

    PubMed Central

    Yakar, Shoshana; Liu, Jun-Li; Stannard, Bethel; Butler, Andrew; Accili, Domenici; Sauer, Brian; LeRoith, Derek

    1999-01-01

    The somatomedin hypothesis proposed that insulin-like growth factor I (IGF-I) was a hepatically derived circulating mediator of growth hormone and is a crucial factor for postnatal growth and development. To reassess this hypothesis, we have used the Cre/loxP recombination system to delete the igf1 gene exclusively in the liver. igf1 gene deletion in the liver abrogated expression of igf1 mRNA and caused a dramatic reduction in circulating IGF-I levels. However, growth as determined by body weight, body length, and femoral length did not differ from wild-type littermates. Although our model proves that hepatic IGF-I is indeed the major contributor to circulating IGF-I levels in mice it challenges the concept that circulating IGF-I is crucial for normal postnatal growth. Rather, our model provides direct evidence for the importance of the autocrine/paracrine role of IGF-I. PMID:10377413

  7. Insulin-like growth factor 1 (IGF-1): a growth hormone

    PubMed Central

    Laron, Z

    2001-01-01

    Aim—To contribute to the debate about whether growth hormone (GH) and insulin-like growth factor 1 (IGF-1) act independently on the growth process. Methods—To describe growth in human and animal models of isolated IGF-1 deficiency (IGHD), such as in Laron syndrome (LS; primary IGF-1 deficiency and GH resistance) and IGF-1 gene or GH receptor gene knockout (KO) mice. Results—Since the description of LS in 1966, 51 patients were followed, many since infancy. Newborns with LS are shorter (42–47 cm) than healthy babies (49–52 cm), suggesting that IGF-1 has some influence on intrauterine growth. Newborn mice with IGF-1 gene KO are 30% smaller. The postnatal growth rate of patients with LS is very slow, the distance from the lowest normal centile increasing progressively. If untreated, the final height is 100–136 cm for female and 109–138 cm for male patients. They have acromicia, organomicria including the brain, heart, gonads, genitalia, and retardation of skeletal maturation. The availability of biosynthetic IGF-1 since 1988 has enabled it to be administered to children with LS. It accelerated linear growth rates to 8–9 cm in the first year of treatment, compared with 10–12 cm/year during GH treatment of IGHD. The growth rate in following years was 5–6.5 cm/year. Conclusion—IGF-1 is an important growth hormone, mediating the protein anabolic and linear growth promoting effect of pituitary GH. It has a GH independent growth stimulating effect, which with respect to cartilage cells is possibly optimised by the synergistic action with GH. PMID:11577173

  8. Factors modulating cottongrass seedling growth stimulation to enhanced nitrogen and carbon dioxide: compensatory tradeoffs in leaf dynamics and allocation to meet potassium-limited growth.

    PubMed

    Siegenthaler, Andy; Buttler, Alexandre; Grosvernier, Philippe; Gobat, Jean-Michel; Nilsson, Mats B; Mitchell, Edward A D

    2013-02-01

    Eriophorum vaginatum is a characteristic species of northern peatlands and a keystone plant for cutover bog restoration. Understanding the factors affecting E. vaginatum seedling establishment (i.e. growth dynamics and allocation) under global change has practical implications for the management of abandoned mined bogs and restoration of their C-sequestration function. We studied the responses of leaf dynamics, above- and belowground biomass production of establishing seedlings to elevated CO(2) and N. We hypothesised that nutrient factors such as limitation shifts or dilutions would modulate growth stimulation. Elevated CO(2) did not affect biomass, but increased the number of young leaves in spring (+400 %), and the plant vitality (i.e. number of green leaves/total number of leaves) (+3 %), both of which were negatively correlated to [K(+)] in surface porewater, suggesting a K-limited production of young leaves. Nutrient ratios in green leaves indicated either N and K co-limitation or K limitation. N addition enhanced the number of tillers (+38 %), green leaves (+18 %), aboveground and belowground biomass (+99, +61 %), leaf mass-to-length ratio (+28 %), and reduced the leaf turnover (-32 %). N addition enhanced N availability and decreased [K(+)] in spring surface porewater. Increased tiller and leaf production in July were associated with a doubling in [K(+)] in surface porewater suggesting that under enhanced N production is K driven. Both experiments illustrate the importance of tradeoffs in E. vaginatum growth between: (1) producing tillers and generating new leaves, (2) maintaining adult leaves and initiating new ones, and (3) investing in basal parts (corms) for storage or in root growth for greater K uptake. The K concentration in surface porewater is thus the single most important factor controlling the growth of E. vaginatum seedlings in the regeneration of selected cutover bogs.

  9. Mitochondrial respiratory control is lost during growth factor deprivation.

    PubMed

    Gottlieb, Eyal; Armour, Sean M; Thompson, Craig B

    2002-10-01

    The ability of cells to maintain a bioenergetically favorable ATP/ADP ratio confers a tight balance between cellular events that consume ATP and the rate of ATP production. However, after growth factor withdrawal, the cellular ATP/ADP ratio declines. To investigate these changes, mitochondria from growth factor-deprived cells isolated before the onset of apoptosis were characterized in vitro. Mitochondria from growth factor-deprived cells have lost their ability to undergo matrix condensation in response to ADP, which is accompanied by a failure to perform ADP-coupled respiration. At the time of analysis, mitochondria from growth factor-deprived cells were not depleted of cytochrome c and cytochrome c-dependent respiration was unaffected, demonstrating that the inhibition of the respiratory rate is not due to loss of cytochrome c. Agents that disrupt the mitochondrial outer membrane, such as digitonin, or maintain outer membrane exchange of adenine nucleotide, such as Bcl-x(L), restored ADP-dependent control of mitochondrial respiration. Together, these data suggest that the regulation of mitochondrial outer membrane permeability contributes to respiratory control.

  10. Mitochondrial respiratory control is lost during growth factor deprivation

    PubMed Central

    Gottlieb, Eyal; Armour, Sean M.; Thompson, Craig B.

    2002-01-01

    The ability of cells to maintain a bioenergetically favorable ATP/ADP ratio confers a tight balance between cellular events that consume ATP and the rate of ATP production. However, after growth factor withdrawal, the cellular ATP/ADP ratio declines. To investigate these changes, mitochondria from growth factor-deprived cells isolated before the onset of apoptosis were characterized in vitro. Mitochondria from growth factor-deprived cells have lost their ability to undergo matrix condensation in response to ADP, which is accompanied by a failure to perform ADP-coupled respiration. At the time of analysis, mitochondria from growth factor-deprived cells were not depleted of cytochrome c and cytochrome c-dependent respiration was unaffected, demonstrating that the inhibition of the respiratory rate is not due to loss of cytochrome c. Agents that disrupt the mitochondrial outer membrane, such as digitonin, or maintain outer membrane exchange of adenine nucleotide, such as Bcl-xL, restored ADP-dependent control of mitochondrial respiration. Together, these data suggest that the regulation of mitochondrial outer membrane permeability contributes to respiratory control. PMID:12228733

  11. The Effect of Additives on the Early Stages of Growth of Calcite Single Crystals

    PubMed Central

    Freeman, Colin L.; Gong, Xiuqing; Levenstein, Mark A.; Wang, Yunwei; Kulak, Alexander; Anduix‐Canto, Clara; Lee, Phillip A.; Li, Shunbo; Chen, Li; Christenson, Hugo K.

    2017-01-01

    Abstract As crystallization processes are often rapid, it can be difficult to monitor their growth mechanisms. In this study, we made use of the fact that crystallization proceeds more slowly in small volumes than in bulk solution to investigate the effects of the soluble additives Mg2+ and poly(styrene sulfonate) (PSS) on the early stages of growth of calcite crystals. Using a “Crystal Hotel” microfluidic device to provide well‐defined, nanoliter volumes, we observed that calcite crystals form via an amorphous precursor phase. Surprisingly, the first calcite crystals formed are perfect rhombohedra, and the soluble additives have no influence on the morphology until the crystals reach sizes of 0.1–0.5 μm for Mg2+ and 1–2 μm for PSS. The crystals then continue to grow to develop morphologies characteristic of these additives. These results can be rationalized by considering additive binding to kink sites, which is consistent with crystal growth by a classical mechanism. PMID:28767197

  12. E2F1 transcription factor and its impact on growth factor and cytokine signaling.

    PubMed

    Ertosun, Mustafa Gokhan; Hapil, Fatma Zehra; Osman Nidai, Ozes

    2016-10-01

    E2F1 is a transcription factor involved in cell cycle regulation and apoptosis. The transactivation capacity of E2F1 is regulated by pRb. In its hypophosphorylated form, pRb binds and inactivates DNA binding and transactivating functions of E2F1. The growth factor stimulation of cells leads to activation of CDKs (cyclin dependent kinases), which in turn phosphorylate Rb and hyperphosphorylated Rb is released from E2F1 or E2F1/DP complex, and free E2F1 can induce transcription of several genes involved in cell cycle entry, induction or inhibition of apoptosis. Thus, growth factors and cytokines generally utilize E2F1 to direct cells to either fate. Furthermore, E2F1 regulates expressions of various cytokines and growth factor receptors, establishing positive or negative feedback mechanisms. This review focuses on the relationship between E2F1 transcription factor and cytokines (IL-1, IL-2, IL-3, IL-6, TGF-beta, G-CSF, LIF), growth factors (EGF, KGF, VEGF, IGF, FGF, PDGF, HGF, NGF), and interferons (IFN-α, IFN-β and IFN-γ). Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Glial cell line-derived neurotrophic factor in combination with insulin-like growth factor 1 and basic fibroblast growth factor promote in vitro culture of goat spermatogonial stem cells.

    PubMed

    Bahadorani, M; Hosseini, S M; Abedi, P; Abbasi, H; Nasr-Esfahani, M H

    2015-01-01

    Growth factors are increasingly considered as important regulators of spermatogonial stem cells (SSCs). This study investigated the effects of various growth factors (GDNF, IGF1, bFGF, EGF and GFRalpha-1) on purification and colonization of undifferentiated goat SSCs under in vitro and in vivo conditions. Irrespective of the culture condition used, the first signs of developing colonies were observed from day 4 of culture onwards. The number of colonies developed in GDNF + IGF1 + bFGF culture condition was significantly higher than the other groups (p < 0.05). In contrast, the size of colonies developed in GDNF + EGF + LIF culture condition was significantly higher than the other groups (p < 0.05). Immunocytochemical stationing for specific biomarkers of somatic cells (vimentin, alpha-inhibin and α-SMA) and spermatogonial cells (PLZF, THY 1, VASA, alpha-1 integrin, bet-1 integrin and DBA) revealed that both cell types existed in developing colonies, irrespective of the culture condition used. Even though, the relative abundance of VASA, FGFR3, OCT4, PLZF, BCL6B and THY1 transcription factors in GDNF + IGF1 + bFGF treatment group was significantly higher than the other groups (p < 0.05). Additionally, goat SSCs developed in the latter culture condition could colonize within the seminiferous tubules of the germ-cell depleted recipient mice following xenotransplantation. Obtained results demonstrated that combination of GDNF with IGF1 and bFGF promote in vitro culture of goat SSCs while precludes uncontrolled proliferation of somatic cells.

  14. Natural Killer Cells Control Tumor Growth by Sensing a Growth Factor.

    PubMed

    Barrow, Alexander D; Edeling, Melissa A; Trifonov, Vladimir; Luo, Jingqin; Goyal, Piyush; Bohl, Benjamin; Bando, Jennifer K; Kim, Albert H; Walker, John; Andahazy, Mary; Bugatti, Mattia; Melocchi, Laura; Vermi, William; Fremont, Daved H; Cox, Sarah; Cella, Marina; Schmedt, Christian; Colonna, Marco

    2018-01-25

    Many tumors produce platelet-derived growth factor (PDGF)-DD, which promotes cellular proliferation, epithelial-mesenchymal transition, stromal reaction, and angiogenesis through autocrine and paracrine PDGFRβ signaling. By screening a secretome library, we found that the human immunoreceptor NKp44, encoded by NCR2 and expressed on natural killer (NK) cells and innate lymphoid cells, recognizes PDGF-DD. PDGF-DD engagement of NKp44 triggered NK cell secretion of interferon gamma (IFN)-γ and tumor necrosis factor alpha (TNF-α) that induced tumor cell growth arrest. A distinctive transcriptional signature of PDGF-DD-induced cytokines and the downregulation of tumor cell-cycle genes correlated with NCR2 expression and greater survival in glioblastoma. NKp44 expression in mouse NK cells controlled the dissemination of tumors expressing PDGF-DD more effectively than control mice, an effect enhanced by blockade of the inhibitory receptor CD96 or CpG-oligonucleotide treatment. Thus, while cancer cell production of PDGF-DD supports tumor growth and stromal reaction, it concomitantly activates innate immune responses to tumor expansion. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Skeletal Effects of Growth Hormone and Insulin-like Growth Factor-I Therapy

    PubMed Central

    Lindsey, Richard C.; Mohan, Subburaman

    2015-01-01

    The growth hormone/insulin-like growth factor (GH/IGF) axis is critically important for the regulation of bone formation, and deficiencies in this system have been shown to contribute to the development of osteoporosis and other diseases of low bone mass. The GH/IGF axis is regulated by a complex set of hormonal and local factors which can act to regulate this system at the level of the ligands, receptors, IGF binding proteins (IGFBPs), or IGFBP proteases. A combination of in vitro studies, transgenic animal models, and clinical human investigations has provided ample evidence of the importance of the endocrine and local actions of both GH and IGF-I, the two major components of the GH/IGF axis, in skeletal growth and maintenance. GH- and IGF-based therapies provide a useful avenue of approach for the prevention and treatment of diseases such as osteoporosis. PMID:26408965

  16. Stimulation of body weight increase and epiphyseal cartilage growth by insulin like growth factor

    NASA Technical Reports Server (NTRS)

    Ellis, S.

    1981-01-01

    The ability of insulin-like growth factor (IGF) to induce growth in hypophysectomized immature rats was tested by continuous infusion of the partially purified factor at daily doses of 6, 21, and 46 mU for an 8-day period. A dose-dependent growth of the proximal epiphyseal cartilage of the tibia and an associated stimulation of the primary spongiosa were produced by these amounts of IGF. The two highest doses of IGF also resulted in dose-dependent increases of body weight. Gel permeation of the sera at neutrality showed that the large-molecular-weight IGF binding protein was not induced by the infusion of IGF, whereas it ws generated in the sera of hypophysectomized rats that were infused with daily doses of 86 mU of human growth hormone.

  17. Gene expression analysis of growth factor receptors in human chondrocytes in monolayer and 3D pellet cultures

    PubMed Central

    Witt, Anika; Salamon, Achim; Boy, Diana; Hansmann, Doris; Büttner, Andreas; Wree, Andreas; Bader, Rainer; Jonitz-Heincke, Anika

    2017-01-01

    The main goal of cartilage repair is to create functional tissue by enhancing the in vitro conditions to more physiological in vivo conditions. Chondrogenic growth factors play an important role in influencing cartilage homeostasis. Insulin-like growth factor (IGF)-1 and transforming growth factor (TGF)-β1 affect the expression of collagen type II (Col2) and glycosaminoglycans (GAGs) and, therefore, the targeted use of growth factors could make chondrogenic redifferentiation more efficient. In the present study, human chondrocytes were postmortally isolated from healthy articular cartilage and cultivated as monolayer or 3D pellet cultures either under normoxia or hypoxia and stimulated with IGF-1 and/or TGF-β1 to compare the impact of the different growth factors. The mRNA levels of the specific receptors (IGF1R, TGFBR1, TGFBR2) were analyzed at different time points. Moreover, gene expression rates of collagen type 1 and 2 in pellet cultures were observed over a period of 5 weeks. Additionally, hyaline-like Col2 protein and sulphated GAG (sGAG) levels were quantified. Stimulation with IGF-1 resulted in an enhanced expression of IGF1R and TGFBR2 whereas TGF-β1 stimulated TGFBR1 in the monolayer and pellet cultures. In monolayer, the differences reached levels of significance. This effect was more pronounced under hypoxic culture conditions. In pellet cultures, increased amounts of Col2 protein and sGAGs after incubation with TGF-β1 and/or IGF-1 were validated. In summary, constructing a gene expression profile regarding mRNA levels of specific growth factor receptors in monolayer cultures could be helpful for a targeted application of growth factors in cartilage tissue engineering. PMID:28534942

  18. Growth factor delivery: How surface interactions modulate release in vitro and in vivo

    PubMed Central

    King, William J.; Krebsbach, Paul H.

    2013-01-01

    Biomaterial scaffolds have been extensively used to deliver growth factors to induce new bone formation. The pharmacokinetics of growth factor delivery has been a critical regulator of their clinical success. This review will focus on the surface interactions that control the non-covalent incorporation of growth factors into scaffolds and the mechanisms that control growth factor release from clinically relevant biomaterials. We will focus on the delivery of recombinant human bone morphogenetic protein-2 from materials currently used in the clinical practice, but also suggest how general mechanisms that control growth factor incorporation and release delineated with this growth factor could extend to other systems. A better understanding of the changing mechanisms that control growth factor release during the different stages of preclinical development could instruct the development of future scaffolds for currently untreatable injuries and diseases. PMID:22433783

  19. Enhanced actions of insulin-like growth factor-I and interferon-alpha co-administration in experimental cirrhosis.

    PubMed

    Tutau, Federico; Rodríguez-Ortigosa, Carlos; Puche, Juan Enrique; Juanarena, Nerea; Monreal, Iñigo; García Fernández, María; Clavijo, Encarna; Castilla, Alberto; Castilla-Cortázar, Inma

    2009-01-01

    Cirrhosis is a diffuse process of hepatic fibrosis and regenerative nodule formation. The liver is the major source of circulating insulin-like growth factor-I (IGF-I) whose plasma levels are diminished in cirrhosis. IGF-I supplementation has been shown to induce beneficial effects in cirrhosis, including antifibrogenic and hepatoprotective effects. On other hand, interferon-alpha (IFN-alpha) therapy seems to suppress the progression of hepatic fibrosis. The aim of this study was to investigate the effect of the co-administration of IGF-I+IFN-alpha to Wistar rats with CCl(4)-induced cirrhosis, exploring liver function tests, hepatic lipid peroxidation and histopathology. The mechanisms underlying the effects of these agents were studied by reverse transcription-polymerase chain reaction, determining the expression of some factors [hepatocyte growth factor (HGF), transforming growth factor-beta (TGF-beta), alpha-smooth muscle actin, collagen, tissular inhibitor of metalloproteinases-1 and pregnane X receptor (PXR)] involved in fibrogenesis, fibrolysis and/or hepatoprotection. Both IGF-I and IFN-alpha exerted significant effects on fibrogenesis. IGF-I significantly increased serum albumin and HGF whereas IFN-alpha-therapy did not. The inhibition of TGF-beta expression was only observed by the effect of IFN-alpha-therapy. In addition, only the co-administration of IGF-I and IFN-alpha was able to increase the PXR. The combined therapy with both factors improved liver function tests, hepatic lipid peroxidation and reduced fibrosis, inducing a relevant histological improvement, reducing fibrosis and recovering hepatic architecture. The co-administration IGF-I+IFN enhanced all the beneficial effects observed with each factor separately, showing an additive action on histopathology and PXR expression, which is involved in the inhibition of fibrogenesis.

  20. Ozone dosing alters the biological potential and therapeutic outcomes of plasma rich in growth factors.

    PubMed

    Anitua, E; Zalduendo, M M; Troya, M; Orive, G

    2015-04-01

    Until now, ozone has been used in a rather empirical way. This in-vitro study investigates, for the first time, whether different ozone treatments of plasma rich in growth factors (PRGF) alter the biological properties and outcomes of this autologous platelet-rich plasma. Human plasma rich in growth factors was treated with ozone using one of the following protocols: a continuous-flow method; or a syringe method in which constant volumes of ozone and PRGF were mixed. In both cases, ozone was added before, during and after the addition of calcium chloride. Three ozone concentrations, of the therapeutic range 20, 40 and 80 μg/mL, were tested. Fibrin clot properties, growth factor content and the proliferative effect on primary osteoblasts and gingival fibroblasts were evaluated. Ozone treatment of PRGF using the continuous flow protocol impaired formation of the fibrin scaffold, drastically reduced the levels of growth factors and significantly decreased the proliferative potential of PRGF on primary osteoblasts and gingival fibroblasts. In contrast, treatment of PRGF with ozone using the syringe method, before, during and after the coagulation process, did not alter the biological outcomes of the autologous therapy. These findings suggest that ozone dose and the way that ozone combines with PRGF may alter the biological potential and therapeutic outcomes of PRGF. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Insulin-like growth factor-mediated muscle differentiation: collaboration between phosphatidylinositol 3-kinase-Akt-signaling pathways and myogenin.

    PubMed

    Tureckova, J; Wilson, E M; Cappalonga, J L; Rotwein, P

    2001-10-19

    The differentiation and maturation of skeletal muscle require interactions between signaling pathways activated by hormones and growth factors and an intrinsic regulatory network controlled by myogenic transcription factors. Insulin-like growth factors (IGFs) play key roles in muscle development in the embryo and in regeneration in the adult. To study mechanisms of IGF action in muscle, we developed a myogenic cell line that overexpresses IGF-binding protein-5. C2BP5 cells remain quiescent in low serum differentiation medium until the addition of IGF-I. Here we use this cell line to identify signaling pathways controlling IGF-mediated differentiation. Induction of myogenin by IGF-I and myotube formation were prevented by the phosphatidylinositol (PI) 3-kinase inhibitor, LY294002, even when included 2 days after growth factor addition, whereas expression of active PI 3-kinase could promote differentiation in the absence of IGF-I. Differentiation also was induced by myogenin but was blocked by LY294002. The differentiation-promoting effects of IGF-I were mimicked by a modified membrane-targeted inducible Akt-1 (iAkt), and iAkt was able to stimulate differentiation of C2 myoblasts and primary mouse myoblasts incubated with otherwise inhibitory concentrations of LY294002. These results show that an IGF-regulated PI 3-kinase-Akt pathway controls muscle differentiation by mechanisms acting both upstream and downstream of myogenin.

  2. Molecular targeting of growth factor receptor-bound 2 (Grb2) as an anti-cancer strategy.

    PubMed

    Dharmawardana, Pathirage G; Peruzzi, Benedetta; Giubellino, Alessio; Burke, Terrence R; Bottaro, Donald P

    2006-01-01

    Growth factor receptor-bound 2 (Grb2) is a ubiquitously expressed adapter protein that provides a critical link between cell surface growth factor receptors and the Ras signaling pathway. As such, it has been implicated in the oncogenesis of several important human malignancies. In addition to this function, research over the last decade has revealed other fundamental roles for Grb2 in cell motility and angiogenesis--processes that also contribute to tumor growth, invasiveness and metastasis. This functional profile makes Grb2 a high priority target for anti-cancer drug development. Knowledge of Grb2 protein structure, its component Src homology domains and their respective structure-function relationships has facilitated the rapid development of sophisticated drug candidates that can penetrate cells, bind Grb2 with high affinity and potently antagonize Grb2 signaling. These novel compounds offer considerable promise in our growing arsenal of rationally designed anti-cancer therapeutics.

  3. Up-regulation of proproliferative genes and the ligand/receptor pair placental growth factor and vascular endothelial growth factor receptor 1 in hepatitis C cirrhosis.

    PubMed

    Huang, Xiao X; McCaughan, Geoffrey W; Shackel, Nicholas A; Gorrell, Mark D

    2007-09-01

    Cirrhosis can lead to hepatocellular carcinoma (HCC). Non-diseased liver and hepatitis C virus (HCV)-associated cirrhosis with or without HCC were compared. Proliferation pathway genes, immune response genes and oncogenes were analysed by a quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and immunostaining. Real-time RT-PCR showed up-regulation of genes in HCV cirrhosis including the proliferation-associated genes bone morphogenetic protein 3 (BMP3), placental growth factor 3 (PGF3), vascular endothelial growth factor receptor 1 (VEGFR1) and soluble VEGFR1, the oncogene FYN, and the immune response-associated genes toll-like receptor 9 (TLR9) and natural killer cell transcript 4 (NK4). Expressions of TLR2 and the oncogenes B-cell CLL/lymphoma 9 (BCL9) and PIM2 were decreased in HCV cirrhosis. In addition, PIM2 and TLR2 were increased in HCV cirrhosis with HCC compared with HCV cirrhosis. The ligand/receptor pair PGF and VEGFR1 was intensely expressed by the portal tract vascular endothelium. VEGFR1 was expressed in reactive biliary epithelial structures in fibrotic septum and in some stellate cells and macrophages. PGF and VEGFR1 may have an important role in the pathogenesis of the neovascular response in cirrhosis.

  4. Cytokines and growth factors which regulate bone cell function

    NASA Astrophysics Data System (ADS)

    Seino, Yoshiki

    Everybody knows that growth factors are most important in making bone. Hormones enhance bone formation from a long distance. Growth factors promote bone formation as an autocrine or paracrine factor in nearby bone. BMP-2 through BMP-8 are in the TGF-β family. BMP makes bone by enchondral ossification. In bone, IGF-II is most abundant, second, TGF-β, and third IGF-I. TGF-β enhances bone formation mainly by intramembranous ossification in vivo. TGF-β affects both cell proliferation and differentiation, however, TGF-β mainly enhances bone formation by intramembranous ossification. Interestingly, TGF-β is increased by estrogen(E 2), androgen, vitamin D, TGF-β and FGF. IGF-I and IGF-II also enhance bone formation. At present it remains unclear why IGF-I is more active in bone formation than IGF-II, although IGF-II is more abundant in bone compared to IGF-I. However, if only type I receptor signal transduction promotes bone formation, the strong activity of IGF-I in bone formation is understandable. GH, PTH and E 2 promotes IGF-I production. Recent data suggest that hormones containing vitamin D or E 2 enhance bone formation through growth factors. Therefore, growth factors are the key to clarifying the mechanism of bone formation.

  5. Regulation of insulin-like growth factor I receptors on vascular smooth muscle cells by growth factors and phorbol esters.

    PubMed

    Ververis, J J; Ku, L; Delafontaine, P

    1993-06-01

    Insulin-like growth factor I (IGF I) is an important mitogen for vascular smooth muscle cells. To characterize regulation of vascular IGF I receptors, we performed radioligand displacement experiments using rat aortic smooth muscle cells (RASMs). Serum deprivation for 48 hours caused a 40% decrease in IGF I receptor number. Exposure of quiescent RASMs to platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), or angiotensin II (Ang II) caused a 1.5-2.0-fold increase in IGF I receptors per cell. After FGF exposure, there was a marked increase in the mitogenic response to IGF I. IGF I downregulated its receptors in the presence of platelet-poor plasma. Stimulation of protein kinase C (PKC) by exposure of quiescent RASMs to phorbol 12-myristate 13-acetate caused a biphasic response in IGF I binding; there was a 42% decrease in receptor number at 45 minutes and a 238% increase at 24 hours. To determine the role of PKC in growth factor-induced regulation of IGF I receptors, we downregulated PKC by exposing RASMs to phorbol 12,13-dibutyrate (PDBu) for 48 hours. PDGF- and FGF- but not Ang II-mediated upregulation of IGF I receptors was completely inhibited in PDBu-treated cells. Thus, acute PKC activation by phorbol esters inhibits IGF I binding, whereas chronic PKC activation increases IGF I binding. PDGF and FGF but not Ang II regulate vascular IGF I receptors through a PKC-dependent pathway. These data provide new insights into the regulation of vascular smooth muscle cell IGF I receptors in vitro and are of potential importance in characterizing vascular proliferative responses in vivo.

  6. Growth Hormone and Insulin-Like Growth Factor-1.

    PubMed

    Nicholls, Adam R; Holt, Richard I G

    2016-01-01

    Human growth hormone (GH) was first isolated from the human pituitary gland in 1945 and found to promote the growth of children with hypopituitarism. Since the formation of the World Anti-Doping Association, human GH has appeared on the list of forbidden substances. There is a significant amount of anecdotal evidence that human GH is misused by athletes to enhance performance, and there have been a number of high-profile cases of GH use in professional sport. GH secretagogues (GH-Ss), which increase GH secretion, and insulin-like growth factor (IGF-1), which mediates many of the effects of GH, are also misused, although there is less evidence for this. The effectiveness of GH, IGF-1, and GH-Ss as performance-enhancing drugs remains unclear. Evidence from studies of GH use in people with hypopituitarism show several desirable outcomes, including increased lean body mass, increased strength, and increased exercise capacity. These anabolic and metabolic properties, coupled with the difficulty in detecting them, make them attractive as agents of misuse. Studies in healthy young adults have also demonstrated a performance benefit with GH and IGF-1. © 2016 S. Karger AG, Basel.

  7. Placental Growth Factor Administration Abolishes Placental Ischemia-Induced Hypertension.

    PubMed

    Spradley, Frank T; Tan, Adelene Y; Joo, Woo S; Daniels, Garrett; Kussie, Paul; Karumanchi, S Ananth; Granger, Joey P

    2016-04-01

    Preeclampsia is a pregnancy-specific disorder of new-onset hypertension. Unfortunately, the most effective treatment is early delivery of the fetus and placenta. Placental ischemia appears central to the pathogenesis of preeclampsia because placental ischemia/hypoxia induced in animals by reduced uterine perfusion pressure (RUPP) or in humans stimulates release of hypertensive placental factors into the maternal circulation. The anti-angiogenic factor soluble fms-like tyrosine kinase-1 (sFlt-1), which antagonizes and reduces bioavailable vascular endothelial growth factor and placental growth factor (PlGF), is elevated in RUPP rats and preeclampsia. Although PlGF and vascular endothelial growth factor are both natural ligands for sFlt-1, vascular endothelial growth factor also has high affinity to VEGFR2 (Flk-1) causing side effects like edema. PlGF is specific for sFlt-1. We tested the hypothesis that PlGF treatment reduces placental ischemia-induced hypertension by antagonizing sFlt-1 without adverse consequences to the mother or fetus. On gestational day 14, rats were randomized to 4 groups: normal pregnant or RUPP±infusion of recombinant human PlGF (180 μg/kg per day; AG31, a purified, recombinant human form of PlGF) for 5 days via intraperitoneal osmotic minipumps. On day 19, mean arterial blood pressure and plasma sFlt-1 were higher and glomerular filtration rate lower in RUPP than normal pregnant rats. Infusion of recombinant human PlGF abolished these changes seen with RUPP along with reducing oxidative stress. These data indicate that the increased sFlt-1 and reduced PlGF resulting from placental ischemia contribute to maternal hypertension. Our novel finding that recombinant human PlGF abolishes placental ischemia-induced hypertension, without major adverse consequences, suggests a strong therapeutic potential for this growth factor in preeclampsia. © 2016 American Heart Association, Inc.

  8. Temporally controlled release of multiple growth factors from a self-assembling peptide hydrogel

    NASA Astrophysics Data System (ADS)

    Bruggeman, Kiara F.; Rodriguez, Alexandra L.; Parish, Clare L.; Williams, Richard J.; Nisbet, David R.

    2016-09-01

    Protein growth factors have demonstrated great potential for tissue repair, but their inherent instability and large size prevents meaningful presentation to biologically protected nervous tissue. Here, we create a nanofibrous network from a self-assembling peptide (SAP) hydrogel to carry and stabilize the growth factors. We significantly reduced growth factor degradation to increase their lifespan by over 40 times. To control the temporal release profile we covalently attached polysaccharide chitosan molecules to the growth factor to increase its interactions with the hydrogel nanofibers and achieved a 4 h delay, demonstrating the potential of this method to provide temporally controlled growth factor delivery. We also describe release rate based analysis to examine the growth factor delivery in more detail than standard cumulative release profiles allow and show that the chitosan attachment method provided a more consistent release profile with a 60% reduction in fluctuations. To prove the potential of this system as a complex growth factor delivery platform we demonstrate for the first time temporally distinct release of multiple growth factors from a single tissue specific SAP hydrogel: a significant goal in regenerative medicine.

  9. Activation of BAD by therapeutic inhibition of epidermal growth factor receptor and transactivation by insulin-like growth factor receptor.

    PubMed

    Gilmore, Andrew P; Valentijn, Anthony J; Wang, Pengbo; Ranger, Ann M; Bundred, Nigel; O'Hare, Michael J; Wakeling, Alan; Korsmeyer, Stanley J; Streuli, Charles H

    2002-08-02

    Novel cancer chemotherapeutics are required to induce apoptosis by activating pro-apoptotic proteins. Both epidermal growth factor (EGF) and insulin-like growth factor (IGF) provide potent survival stimuli in many epithelia, and activation of their receptors is commonly observed in solid human tumors. Here we demonstrate that blockade of the EGF receptor by a new drug in phase III clinical trails for cancer, ZD1839, potently induces apoptosis in mammary epithelial cell lines and primary cultures, as well as in a primary pleural effusion from a breast cancer patient. We identified the mechanism of apoptosis induction by ZD1839. We showed that it prevents cell survival by activating the pro-apoptotic protein BAD. Moreover, we demonstrate that IGF transactivates the EGF receptor and that ZD1839 blocks IGF-mediated phosphorylation of MAPK and BAD. Many cancer therapies kill tumor cells by inducing apoptosis as a consequence of targeting DNA; however, the threshold at which apoptosis can be triggered through DNA damage is often different from that in normal cells. Our results indicate that by targeting a growth factor-mediated survival signaling pathway, BAD phosphorylation can be manipulated therapeutically to induce apoptosis.

  10. Extracellular growth factors and mitogens cooperate to drive mitochondrial biogenesis

    PubMed Central

    Echave, Pedro; Machado-da-Silva, Gisela; Arkell, Rebecca S.; Duchen, Michael R.; Jacobson, Jake; Mitter, Richard; Lloyd, Alison C.

    2009-01-01

    Summary Cells generate new organelles when stimulated by extracellular factors to grow and divide; however, little is known about how growth and mitogenic signalling pathways regulate organelle biogenesis. Using mitochondria as a model organelle, we have investigated this problem in primary Schwann cells, for which distinct factors act solely as mitogens (neuregulin) or as promoters of cell growth (insulin-like growth factor 1; IGF1). We find that neuregulin and IGF1 act synergistically to increase mitochondrial biogenesis and mitochondrial DNA replication, resulting in increased mitochondrial density in these cells. Moreover, constitutive oncogenic Ras signalling results in a further increase in mitochondrial density. This synergistic effect is seen at the global transcriptional level, requires both the ERK and phosphoinositide 3-kinase (PI3K) signalling pathways and is mediated by the transcription factor ERRα. Interestingly, the effect is independent of Akt-TOR signalling, a major regulator of cell growth in these cells. This separation of the pathways that drive mitochondrial biogenesis and cell growth provides a mechanism for the modulation of mitochondrial density according to the metabolic requirements of the cell. PMID:19920079

  11. Nerve Growth Factor Expression Is Not Associated with Perineural Invasion in Extrahepatic Cholangiocarcinoma.

    PubMed

    Urabe, Kazuhide; Murakami, Yoshiaki; Kondo, Naru; Uemura, Kenichiro; Hashimoto, Yasushi; Nakagawa, Naoya; Sasaki, Hayato; Hiyama, Eiso; Takahashi, Shinya; Sueda, Taijiro

    2016-03-01

    Although the presence of perineural invasion has been recognized as a poor prognostic factor in extrahepatic cholangiocarcinoma, the molecular mechanisms of perineural invasion in extrahepatic cholangiocarcinoma remain unclear. Nerve growth factor has been reported to be a candidate predictive biomarker of perineural invasion in some cancers. To investigate the impact of intratumoral nerve growth factor expression in resected extrahepatic cholangiocarcinoma on survival. Intratumoral nerve growth factor expression was investigated immunohistochemically in 112 patients with resected extrahepatic cholangiocarcinoma. Associations between nerve growth factor expression and clinicopathological factors were statistically evaluated, and risk factors for poor survival were analyzed using univariate and multivariate analyses. High and low nerve growth factor expression was observed in 62 (55%) and 50 (45%) patients, respectively. For all 112 patients, no significant correlation was found between nerve growth factor expression and presence of perineural invasion (P = 0.942). Moreover, nerve growth factor expression was not associated with recurrence-free survival (P = 0.861) and overall survival (P = 0.973). In multivariate analysis, lymph node metastasis (P = 0.004) was identified as an independent risk factor for early recurrence and the presence of perineural invasion (P = 0.002) and lymph node metastasis (P < 0.001) was identified as independent risk factors for poor survival. Intratumoral nerve growth factor expression is not associated with perineural invasion or recurrence-free and overall survival in patients with resected extrahepatic cholangiocarcinoma.

  12. Fatigue Crack Growth Rate and Stress-Intensity Factor Corrections for Out-of-Plane Crack Growth

    NASA Technical Reports Server (NTRS)

    Forth, Scott C.; Herman, Dave J.; James, Mark A.

    2003-01-01

    Fatigue crack growth rate testing is performed by automated data collection systems that assume straight crack growth in the plane of symmetry and use standard polynomial solutions to compute crack length and stress-intensity factors from compliance or potential drop measurements. Visual measurements used to correct the collected data typically include only the horizontal crack length, which for cracks that propagate out-of-plane, under-estimates the crack growth rates and over-estimates the stress-intensity factors. The authors have devised an approach for correcting both the crack growth rates and stress-intensity factors based on two-dimensional mixed mode-I/II finite element analysis (FEA). The approach is used to correct out-of-plane data for 7050-T7451 and 2025-T6 aluminum alloys. Results indicate the correction process works well for high DeltaK levels but fails to capture the mixed-mode effects at DeltaK levels approaching threshold (da/dN approximately 10(exp -10) meter/cycle).

  13. Correlation between increasing tissue ischemia and circulating levels of angiogenic growth factors in peripheral artery disease.

    PubMed

    Jalkanen, Juho; Hautero, Olli; Maksimow, Mikael; Jalkanen, Sirpa; Hakovirta, Harri

    2018-04-21

    The aim of the present study was to assess the circulating levels of vascular endothelial growth factor (VEGF) and other suggested therapeutic growth factors with the degree of ischemia in patients with different clinical manifestations of peripheral arterial disease (PAD) according to the Rutherford grades. The study cohort consists of 226 consecutive patients admitted to a Department of Vascular Surgery for elective invasive procedures. PAD patients were grouped according to the Rutherford grades after a clinical assessment. Ankle-brachial pressure indices (ABI) and absolute toe pressure (TP) values were measured. Serum levels of circulating VEGF, hepatocyte growth factor (HGF), basic fibroblast growth factor (bFGF), and platelet derived growth factor (PDGF) were measured from serum and analysed against Rutherford grades and peripheral hemodynamic measurements. The levels of VEGF (P = 0.009) and HGF (P < 0.001) increased significantly as the ischaemic burden became more severe according to the Rutherford grades. PDGF behaved in opposite manner and declined along increasing Rutherford grades (P = 0.004). A significant, inverse correlations between Rutherford grades was detected as follows; VEGF (Pearson's correlation = 0.183, P = 0.004), HGF (Pearson's correlation = 0.253, P < 0.001), bFGF (Pearson's correlation = 0.169, P = 0.008) and PDGF (Pearson's correlation = 0.296, P < 0.001). In addition, VEGF had a clear direct negative correlation with ABI (Pearson's correlation -0.19, P = 0.009) and TP (Pearson's correlation -0.20, P = 0.005) measurements. Our present observations show that the circulating levels of VEGF and other suggested therapeutic growth factors are significantly increased along with increasing ischemia. These findings present a new perspective to anticipated positive effects of gene therapies utilizing VEGF, HGF, and bFGF, because the levels of these growth factors are endogenously high in end

  14. Factors involved in anaerobic growth of Saccharomyces cerevisiae.

    PubMed

    Ishtar Snoek, I S; Yde Steensma, H

    2007-01-01

    Life in the absence of molecular oxygen requires several adaptations. Traditionally, the switch from respiratory metabolism to fermentation has attracted much attention in Saccharomyces cerevisiae, as this is the basis for the use of this yeast in the production of alcohol and in baking. It has also been clear that under anaerobic conditions the yeast is not able to synthesize sterols and unsaturated fatty acids and that for anaerobic growth these have to be added to the media. More recently it has been found that many more factors play a role. Several other biosynthetic reactions also require molecular oxygen and the yeast must have alternatives for these. In addition, the composition of the cell wall and cell membrane show major differences when aerobic and anaerobic cells are compared. All these changes are reflected by the observation that the transcription of more than 500 genes changes significantly between aerobically and anaerobically growing cultures. In this review we will give an overview of the factors that play a role in the survival in the absence of molecular oxygen. Copyright (c) 2007 John Wiley & Sons, Ltd.

  15. The effect of tailor-made additives on crystal growth of methyl paraben: Experiments and modelling

    NASA Astrophysics Data System (ADS)

    Cai, Zhihui; Liu, Yong; Song, Yang; Guan, Guoqiang; Jiang, Yanbin

    2017-03-01

    In this study, methyl paraben (MP) was selected as the model component, and acetaminophen (APAP), p-methyl acetanilide (PMAA) and acetanilide (ACET), which share the similar molecular structure as MP, were selected as the three tailor-made additives to study the effect of tailor-made additives on the crystal growth of MP. HPLC results indicated that the MP crystals induced by the three additives contained MP only. Photographs of the single crystals prepared indicated that the morphology of the MP crystals was greatly changed by the additives, but PXRD and single crystal diffraction results illustrated that the MP crystals were the same polymorph only with different crystal habits, and no new crystal form was found compared with other references. To investigate the effect of the additives on the crystal growth, the interaction between additives and facets was discussed in detail using the DFT methods and MD simulations. The results showed that APAP, PMAA and ACET would be selectively adsorbed on the growth surfaces of the crystal facets, which induced the change in MP crystal habits.

  16. Biological effects of plasma rich in growth factors (PRGF) on human endometrial fibroblasts.

    PubMed

    Anitua, Eduardo; de la Fuente, María; Ferrando, Marcos; Quintana, Fernando; Larreategui, Zaloa; Matorras, Roberto; Orive, Gorka

    2016-11-01

    To evaluate the biological outcomes of plasma rich in growth factors (PRGF) on human endometrial fibroblasts in culture. PRGF was obtained from three healthy donors and human endometrial fibroblasts (HEF) were isolated from endometrial specimens from five healthy women. The effects of PRGF on cell proliferation and migration, secretion of vascular endothelial growth factor (VEGF), procollagen type I and hyaluronic acid (HA) and contractility of isolated and cultured human endometrial fibroblasts (HEF) were analyzed. Statistical analysis was performed in order to compare the effects of PRGF with respect to control situation (T-test or Mann-Whitney U-test). We report a significantly elevated human endometrial fibroblast proliferation and migration after treatment with PRGF. In addition, stimulation of HEF with PRGF induced an increased expression of the angiogenic factor VEGF and favored the endometrial matrix remodeling by the secretion of procollagen type I and HA and endometrial regeneration by elevating the contractility of HEF. These results were obtained for all PRGF donors and each endometrial cell line. The myriad of growth factors contained in PRGF promoted HEF proliferation, migration and synthesis of paracrine molecules apart from increasing their contractility potential. These preliminary results suggest that PRGF improves the biological activity of HEF in vitro, enhancing the regulation of several cellular processes implied in endometrial regeneration. This innovative treatment deserves further investigation for its potential in "in vivo" endometrial development and especially in human embryo implantation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  17. Inhibiting platelet-derived growth factor beta reduces Ewing's sarcoma growth and metastasis in a novel orthotopic human xenograft model.

    PubMed

    Wang, Yong Xin; Mandal, Deendayal; Wang, Suizhau; Hughes, Dennis; Pollock, Raphael E; Lev, Dina; Kleinerman, Eugenie; Hayes-Jordan, Andrea

    2009-01-01

    Despite aggressive therapy, Ewing's sarcoma (ES) patients have a poor five-year overall survival of only 20-40%. Pulmonary metastasis is the most common form of demise in these patients. The pathogenesis of pulmonary metastasis is poorly understood and few orthotopic models exist that allow study of spontaneous pulmonary metastasis in ES. We have developed a novel orthotopic xenograft model in which spontaneous pulmonary metastases develop. While the underlying biology of ES is incompletely understood, in addition to the EWS-FLI-1 mutation, it is known that platelet-derived growth factor receptor beta (PDGFR-beta) is highly expressed in ES. Hypothesizing that PDGFR-beta expression is indicative of a specific role for this receptor protein in ES progression, the effect of PDGFR-beta inhibition on ES growth and metastasis was assessed in this novel orthotopic ES model. Silencing PDGFR-beta reduced spontaneous growth and metastasis in ES. Preclinical therapeutically relevant findings such as these may ultimately lead to new treatment initiatives in ES.

  18. Defective lysosomal targeting of activated fibroblast growth factor receptor 3 in achondroplasia.

    PubMed

    Cho, Jay Y; Guo, Changsheng; Torello, Monica; Lunstrum, Gregory P; Iwata, Tomoko; Deng, Chuxia; Horton, William A

    2004-01-13

    Mutations of fibroblast growth factor receptor 3 (FGFR3) are responsible for achondroplasia (ACH) and related dwarfing conditions in humans. The pathogenesis involves constitutive activation of FGFR3, which inhibits proliferation and differentiation of growth plate chondrocytes. Here we report that activating mutations in FGFR3 increase the stability of the receptor. Our results suggest that the mutations disrupt c-Cbl-mediated ubiquitination that serves as a targeting signal for lysosomal degradation and termination of receptor signaling. The defect allows diversion of actively signaling receptors from lysosomes to a recycling pathway where their survival is prolonged, and, as a result, their signaling capacity is increased. The lysosomal targeting defect is additive to other mechanisms proposed to explain the pathogenesis of ACH.

  19. Quantification of growth factor signaling and pathway cross talk by live-cell imaging

    PubMed Central

    Gross, Sean M.

    2017-01-01

    Peptide growth factors stimulate cellular responses through activation of their transmembrane receptors. Multiple intracellular signaling cascades are engaged following growth factor–receptor binding, leading to short- and long-term biological effects. Each receptor-activated signaling pathway does not act in isolation but rather interacts at different levels with other pathways to shape signaling networks that are distinctive for each growth factor. To gain insights into the specifics of growth factor-regulated interactions among different signaling cascades, we developed a HeLa cell line stably expressing fluorescent live-cell imaging reporters that are readouts for two major growth factor-stimulated pathways, Ras–Raf–Mek–ERK and phosphatidylinositol (PI) 3-kinase–Akt. Incubation of cells with epidermal growth factor (EGF) resulted in rapid, robust, and sustained ERK signaling but shorter-term activation of Akt. In contrast, hepatocyte growth factor induced sustained Akt signaling but weak and short-lived ERK activity, and insulin-like growth factor-I stimulated strong long-term Akt responses but negligible ERK signaling. To address potential interactions between signaling pathways, we employed specific small-molecule inhibitors. In cells incubated with EGF or platelet-derived growth factor-AA, Raf activation and the subsequent stimulation of ERK reduced Akt signaling, whereas Mek inhibition, which blocked ERK activation, enhanced Akt and turned transient effects into sustained responses. Our results reveal that individual growth factors initiate signaling cascades that vary markedly in strength and duration and demonstrate in living cells the dramatic effects of cross talk from Raf and Mek to PI 3-kinase and Akt. Our data further indicate how specific growth factors can encode distinct cellular behaviors by promoting complex interactions among signaling pathways. PMID:28100485

  20. Effects of Growth Factors on Dental Stem/ProgenitorCells

    PubMed Central

    Kim, Sahng G.; Solomon, Charles; Zheng, Ying; Suzuki, Takahiro; Mo, Chen; Song, Songhee; Jiang, Nan; Cho, Shoko; Zhou, Jian; Mao, Jeremy J.

    2014-01-01

    Synopsis The primary goal of regenerative endodontics is to restore the vitality and functions of the dentin-pulp complex, as opposed to filing of the root canal with bioinert materials. Structural restoration is also important but is likely secondary to vitality and functions. Myriads growth factors regulate multiple cellular functions including migration, proliferation, differentiation and apoptosis of several cell types that are intimately involved in dentin-pulp regeneration: odontoblasts, interstitial fibroblasts, vascular-endothelial cells and sprouting nerve fibers. Recent work showing that growth factor delivery, without cell transplantation, can yield pulp-dentin like tissues in vivo provides one of the tangible pathways for regenerative endodontics. This review synthesizes our knowledge on a multitude of growth factors that are known or anticipated to be efficacious in dental pulp-dentin regeneration. PMID:22835538

  1. Neuronal expression of fibroblast growth factor receptors in zebrafish.

    PubMed

    Rohs, Patricia; Ebert, Alicia M; Zuba, Ania; McFarlane, Sarah

    2013-12-01

    Fibroblast growth factor (FGF) signaling is important for a host of developmental processes such as proliferation, differentiation, tissue patterning, and morphogenesis. In vertebrates, FGFs signal through a family of four fibroblast growth factor receptors (FGFR 1-4), one of which is duplicated in zebrafish (FGFR1). Here we report the mRNA expression of the five known zebrafish fibroblast growth factor receptors at five developmental time points (24, 36, 48, 60, and 72h postfertilization), focusing on expression within the central nervous system. We show that the receptors have distinct and dynamic expression in the developing zebrafish brain, eye, inner ear, lateral line, and pharynx. In many cases, the expression patterns are similar to those of homologous FGFRs in mouse, chicken, amphibians, and other teleosts. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Quantification of growth factor signaling and pathway cross talk by live-cell imaging.

    PubMed

    Gross, Sean M; Rotwein, Peter

    2017-03-01

    Peptide growth factors stimulate cellular responses through activation of their transmembrane receptors. Multiple intracellular signaling cascades are engaged following growth factor-receptor binding, leading to short- and long-term biological effects. Each receptor-activated signaling pathway does not act in isolation but rather interacts at different levels with other pathways to shape signaling networks that are distinctive for each growth factor. To gain insights into the specifics of growth factor-regulated interactions among different signaling cascades, we developed a HeLa cell line stably expressing fluorescent live-cell imaging reporters that are readouts for two major growth factor-stimulated pathways, Ras-Raf-Mek-ERK and phosphatidylinositol (PI) 3-kinase-Akt. Incubation of cells with epidermal growth factor (EGF) resulted in rapid, robust, and sustained ERK signaling but shorter-term activation of Akt. In contrast, hepatocyte growth factor induced sustained Akt signaling but weak and short-lived ERK activity, and insulin-like growth factor-I stimulated strong long-term Akt responses but negligible ERK signaling. To address potential interactions between signaling pathways, we employed specific small-molecule inhibitors. In cells incubated with EGF or platelet-derived growth factor-AA, Raf activation and the subsequent stimulation of ERK reduced Akt signaling, whereas Mek inhibition, which blocked ERK activation, enhanced Akt and turned transient effects into sustained responses. Our results reveal that individual growth factors initiate signaling cascades that vary markedly in strength and duration and demonstrate in living cells the dramatic effects of cross talk from Raf and Mek to PI 3-kinase and Akt. Our data further indicate how specific growth factors can encode distinct cellular behaviors by promoting complex interactions among signaling pathways. Copyright © 2017 the American Physiological Society.

  3. Increased Serum Levels of Epidermal Growth Factor in Children with Autism

    ERIC Educational Resources Information Center

    Iseri, Elvan; Guney, Esra; Ceylan, Mehmet F.; Yucel, Aysegul; Aral, Arzu; Bodur, Sahin; Sener, Sahnur

    2011-01-01

    The etiology of autism is unclear, however autism is considered as a multifactorial disorder that is influenced by neurological, environmental, immunological and genetic factors. Growth factors, including epidermal growth factor (EGF), play an important role in the celluler proliferation and the differentiation of the central and peripheral…

  4. Growth factors in the anterior segment: role in tissue maintenance, wound healing and ocular pathology.

    PubMed

    Klenkler, Bettina; Sheardown, Heather

    2004-11-01

    A number of growth factors and their associated receptors, including epidermal growth factor, transforming growth factor-beta, keratinocyte growth factor, hepatocyte growth factor, fibroblast growth factor and platelet-derived growth factor have been detected in the anterior segment of the eye. On binding to cellular receptors, these factors activate signalling cascades, which regulate functions including mitosis, differentiation, motility and apoptosis. Production of growth factors by corneal cells and their presence in the tear fluid and aqueous humour is essential for maintenance and renewal of normal tissue in the anterior eye and the prevention of undesirable immune or angiogenic reactions. Growth factors also play a vital role in corneal wound healing, mediating the proliferation of epithelial and stromal tissue and affecting the remodelling of the extracellular matrix (ECM). These functions depend on a complex interplay between growth factors of different types, the ECM, and regulatory mechanisms of the affected cells. Imbalances may lead to deficient wound healing and various ocular pathologies, including edema, neovascularization and glaucoma. Growth factors may be targeted in therapeutic ophthalmic applications, through exogenous application or selective inhibition, and may be used to elicit specific cellular responses to ophthalmic materials. A thorough understanding of the mechanism and function of growth factors and their actions in the complex environment of the anterior eye is required for these purposes. Growth factors, their function and mechanisms of action as well as the interplay between different growth factors based on recent in vitro and in vivo studies are presented.

  5. Phytoplankton growth response to Asian dust addition in the northwest Pacific Ocean versus the Yellow Sea

    NASA Astrophysics Data System (ADS)

    Zhang, Chao; Gao, Huiwang; Yao, Xiaohong; Shi, Zongbo; Shi, Jinhui; Yu, Yang; Meng, Ling; Guo, Xinyu

    2018-02-01

    In this study, five on-board microcosm experiments were performed in the subtropical gyre, the Kuroshio Extension region of the northwest Pacific Ocean (NWPO), and the Yellow Sea (YS) in order to investigate phytoplankton growth following the addition of artificially modified mineral dust (AM dust) and various nutrients (nitrogen (N), phosphorus (P), iron (Fe), N + P, and N + P + Fe). The two experiments carried out with AM-dust addition in the subtropical gyre showed a maximum chlorophyll a (Chl a) concentration increase of 1.7- and 2.8-fold, while the cell abundance of large-sized phytoplankton ( > 5 µm) showed a 1.8- and 3.9-fold increase, respectively, relative to the controls. However, in the Kuroshio Extension region and the YS, the increases in maximum Chl a and cell abundance of large-sized phytoplankton following AM-dust addition were at most 1.3-fold and 1.7-fold larger than those in the controls, respectively. A net conversion efficiency index (NCEI) newly proposed in this study, size-fractionated Chl a, and the abundance of large-sized phytoplankton were analysed to determine which nutrients contribute to supporting phytoplankton growth. Our results demonstrate that a combination of nutrients, N-P or N + P + Fe, is responsible for phytoplankton growth in the subtropical gyre following AM-dust addition. Single nutrient addition, i.e., N in the Kuroshio Extension region and P or N in the YS, controls the phytoplankton growth following AM-dust addition. In the AM-dust-addition experiments, in which the increased N-P or P was identified to determine phytoplankton growth, the dissolved inorganic P from AM dust (8.6 nmol L-1) was much lower than the theoretically estimated minimum P demand (˜ 20 nmol L-1) for phytoplankton growth. These observations suggest that additional supply augments the bioavailable P stock in incubated seawater with AM-dust addition, most likely due to an enhanced solubility of P from AM dust or the remineralization of the dissolved

  6. Colocalization of insulin-like growth factor-binding protein with insulin-like growth factor I.

    PubMed

    Kobayashi, S; Clemmons, D R; Venkatachalam, M A

    1991-07-01

    We report the localization of insulin-like growth factor I (IGF-I) and a 25-kDa form of insulin-like growth factor-binding protein (IGF-BP-1) in adult rat kidney. The antigens were localized using a rabbit anti-human IGF-I antibody, and a rabbit anti-human IGF-BP-1 antibody raised against human 25-kDa IGF-BP-1 purified from amniotic fluid. Immunohistochemistry by the avidin-biotin peroxidase conjugate technique showed that both peptides are located in the same nephron segments, in the same cell types. The most intense staining was in papillary collecting ducts. There was moderate staining also in cortical collecting ducts and medullary thick ascending limbs of Henle's loop. In collecting ducts the antigens were shown to be present in principal cells but not in intercalated cells. In distal convoluted tubules, cortical thick ascending limbs, and in structures presumptively identified as thin limbs of Henle's loops there was only modest staining. The macula densa, however, lacked immunoreactivity. Colocalization of IGF-I and IGF-BP-1 in the same cells supports the notion, derived from studies on cultured cells, that the actions of IGF-I may be modified by IGF-BPs that are present in the same location.

  7. Alk5-Mediated Transforming Growth Factor β Signaling Acts Upstream of Fibroblast Growth Factor 10 To Regulate the Proliferation and Maintenance of Dental Epithelial Stem Cells▿

    PubMed Central

    Zhao, Hu; Li, Sha; Han, Dong; Kaartinen, Vesa; Chai, Yang

    2011-01-01

    Mouse incisors grow continuously throughout life. This growth is supported by the division of dental epithelial stem cells that reside in the cervical loop region. Little is known about the maintenance and regulatory mechanisms of dental epithelial stem cells. In the present study, we investigated how transforming growth factor β (TGF-β) signaling-mediated mesenchymal-epithelial cell interactions control dental epithelial stem cells. We designed two approaches using incisor organ culture and bromodeoxyuridine (BrdU) pulse-chase experiments to identify and evaluate stem cell functions. We show that the loss of the TGF-β type I receptor (Alk5) in the cranial neural crest-derived dental mesenchyme severely affects the proliferation of TA (transit-amplifying) cells and the maintenance of dental epithelial stem cells. Incisors of Wnt1-Cre; Alk5fl/fl mice lost their ability to continue to grow in vitro. The number of BrdU label-retaining cells (LRCs) was dramatically reduced in Alk5 mutant mice. Fgf10, Fgf3, and Fgf9 signals in the dental mesenchyme were downregulated in Wnt1-Cre; Alk5fl/fl incisors. Strikingly, the addition of exogenous fibroblast growth factor 10 (FGF10) into cultured incisors rescued dental epithelial stem cells in Wnt1-Cre; Alk5fl/fl mice. Therefore, we propose that Alk5 functions upstream of Fgf10 to regulate TA cell proliferation and stem cell maintenance and that this signaling mechanism is crucial for stem cell-mediated tooth regeneration. PMID:21402782

  8. Comparative Analysis of Cellular and Growth Factor Composition in Bone Marrow Aspirate Concentrate and Platelet-Rich Plasma.

    PubMed

    Sugaya, Hisashi; Yoshioka, Tomokazu; Kato, Toshiki; Taniguchi, Yu; Kumagai, Hiroshi; Hyodo, Kojiro; Ohneda, Osamu; Yamazaki, Masashi; Mishima, Hajime

    2018-01-01

    The purpose of this study was to quantify the stem cell and growth factor (GF) contents in the bone marrow aspirate concentrate (BMAC) and platelet-rich plasma (PRP) prepared from whole blood using a protocol established in our laboratory. We examined 10 patients with osteonecrosis of the femoral head who were treated by autologous BMAC transplantation at our hospital between January 2015 and June 2015. We quantified CD34+ and CD31-CD45-CD90+CD105+ cells in BMAC and PRP by flow cytometry. Additionally, we measured various GFs, that is, basic fibroblast growth factor (b-FGF), platelet-derived growth factor-BB (PDGF-BB), vascular endothelial growth factor (VEGF), transforming growth factor- β 1 (TGF- β 1), and bone morphogenetic protein-2 (BMP-2) in BMAC and PRP using enzyme-linked immunosorbent assays and statistical analyses. CD34+ and CD31-45-90+105+ cells accounted for approximately 1.9% and 0.03% of cells in BMAC and no cells in PRP. The concentration of b-FGF was higher in BMAC than in PRP ( P < 0.001), whereas no significant differences in the levels of PDGF-BB, VEGF, TGF- β 1, and BMP-2 were observed between the two types of sample. BMAC had an average of 1.9% CD34+ and 0.03% CD31-45-90+105+ cells and higher levels of b-FGF than those of PRP.

  9. Vascular endothelial growth factor c/vascular endothelial growth factor receptor 3 signaling regulates chemokine gradients and lymphocyte migration from tissues to lymphatics.

    PubMed

    Iwami, Daiki; Brinkman, C Colin; Bromberg, Jonathan S

    2015-04-01

    Circulation of leukocytes via blood, tissue and lymph is integral to adaptive immunity. Afferent lymphatics form CCL21 gradients to guide dendritic cells and T cells to lymphatics and then to draining lymph nodes (dLN). Vascular endothelial growth factor C and vascular endothelial growth factor receptor 3 (VEGFR-3) are the major lymphatic growth factor and receptor. We hypothesized these molecules also regulate chemokine gradients and lymphatic migration. CD4 T cells were injected into the foot pad or ear pinnae, and migration to afferent lymphatics and dLN quantified by flow cytometry or whole mount immunohistochemistry. Vascular endothelial growth factor receptor 3 or its signaling or downstream actions were modified with blocking monoclonal antibodies (mAbs) or other reagents. Anti-VEGFR-3 prevented migration of CD4 T cells into lymphatic lumen and significantly decreased the number that migrated to dLN. Anti-VEGFR-3 abolished CCL21 gradients around lymphatics, although CCL21 production was not inhibited. Heparan sulfate (HS), critical to establish CCL21 gradients, was down-regulated around lymphatics by anti-VEGFR-3 and this was dependent on heparanase-mediated degradation. Moreover, a Phosphoinositide 3-kinase (PI3K)α inhibitor disrupted HS and CCL21 gradients, whereas a PI3K activator prevented the effects of anti-VEGFR-3. During contact hypersensitivity, VEGFR-3, CCL21, and HS expression were all attenuated, and anti-heparanase or PI3K activator reversed these effects. Vascular endothelial growth factor C/VEGFR-3 signaling through PI3Kα regulates the activity of heparanase, which modifies HS and CCL21 gradients around lymphatics. The functional and physical linkages of these molecules regulate lymphatic migration from tissues to dLN. These represent new therapeutic targets to influence immunity and inflammation.

  10. Expression of epidermal growth factor receptor and vascular endothelial growth factor in malignant canine epithelial nasal tumours.

    PubMed

    Shiomitsu, K; Johnson, C L; Malarkey, D E; Pruitt, A F; Thrall, D E

    2009-06-01

    Epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) signalling pathways play a role in carcinogenesis. Inhibition of EGF receptor (EGFR) and of VEGF is effective in increasing the radiation responsiveness of neoplastic cells both in vitro and in human trials. In this study, immunohistochemical evaluation was employed to determine and characterize the potential protein expression levels and patterns of EGFR and VEGF in a variety of canine malignant epithelial nasal tumours. Of 24 malignant canine nasal tumours, 13 (54.2%) were positive for EGFR staining and 22 (91.7%) were positive for VEGF staining. The intensity and percentage of immunohistochemically positive neoplastic cells for EGFR varied. These findings indicate that EGFR and VEGF proteins were present in some malignant epithelial nasal tumours in the dogs, and therefore, it may be beneficial to treat canine patients with tumours that overexpress EGFR and VEGF with specific inhibitors in conjunction with radiation.

  11. Productivity and growth performance of edamame (Glycin Max L Merril) due to the addition of sitokinin

    NASA Astrophysics Data System (ADS)

    Rohmawati, Irma; Ulfah, Maria

    2018-05-01

    Global market demand towards edamame is quite high, but production of edamame is still very low. Edamame have to increased its production. Many researchers stated that sitokinin effect on the activities of enzymes in metabolic processes of plants. This research aims to analyze response of plant physiological Edamame applied with hormones sitokinin especially in aspects of growth and productivity. The research was carried out in March-May 2017. This study used a Randomized Complete Design method with three treatment factors that is A (unannounced sitokinin hormone), B (hormone siokinin 0.5 mL) C (hormone sitokinin 1 mL) with 5 repetitions. The parameters observed were higher plants, number of leaves, and the weight of the fruit. Research shows that treatment with hormone sitokinin effect on the growth and the production of edamame. The addition of the sitokinin hormones can increase the growth of leaves, stems, and fruit productivity. Results of the study showed treatment C (sitokinin 1 mL) gives signifcant effect. At the age of 48 HST by administering hormones 1 mL, has an average height of 28.8 cm, average number of leaves 15, and heavy weight fruit 17.43 grams.

  12. The use of autologous blood-derived growth factors in bone regeneration

    PubMed Central

    Civinini, Roberto; Macera, Armando; Nistri, Lorenzo; Redl, Birgit; Innocenti, Massimo

    2011-01-01

    Platelet-rich plasma (PRP) is defined as a portion of the plasma fraction of autologous blood having platelet concentrations above baseline. When activated the platelets release growth factors that play an essential role in bone healing such as Platelet-derived Growth Factor, Transforming Growth Factor-β, Vascular Endothelial Growth Factor and others. Multiple basic science and in vivo animal studies agree that PRP has a role in the stimulation of the healing cascade in ligament, tendon, muscle cartilage and in bone regeneration in the last years PRP had a widespread diffusion in the treatment of soft tissue and bone healing. The purpose of this review is to describe the biological properties of platelets and its factors, the methods used for producing PRP, to provide a background on the underlying basic science and an overview of evidence based medicine on clinical application of PRP in bone healing. PMID:22461800

  13. Mechanisms of resistance to anti-human epidermal growth factor receptor 2 agents in breast cancer.

    PubMed

    Mukohara, Toru

    2011-01-01

    Approximately 20% of breast cancers are characterized by overexpression of human epidermal growth factor receptor 2 (HER2) protein and associated gene amplification, and the receptor tyrosine kinase is believed to play a critical role in the pathogenesis of these tumors. The development and implementation of trastuzumab, a humanized monoclonal antibody against the extracellular domain of HER2 protein, has significantly improved treatment outcomes in patients with HER2-overexpressing breast cancer. However, despite this clinical usefulness, unmet needs for better prediction of trastuzumab's response and overcoming primary and acquired resistance remain. In this review, we discuss several potential mechanisms of resistance to trastuzumab that have been closely studied over the last decade. Briefly, these mechanisms include: impaired access of trastuzumab to HER2 by expression of extracellular domain-truncated HER2 (p95 HER2) or overexpression of MUC4; alternative signaling from insulin-like growth factor-1 receptor, other epidermal growth factor receptor family members, or MET; aberrant downstream signaling caused by loss of phosphatase and tensin homologs deleted from chromosome 10 (PTEN), PIK3CA mutation, or downregulation of p27; or FCGR3A polymorphisms. In addition, we discuss potential strategies for overcoming resistance to trastuzumab. Specifically, the epidermal growth factor receptor/HER2 tyrosine kinase inhibitor lapatinib partially overcame trastuzumab resistance in a clinical setting, so its efficacy results and limited data regarding potential mechanisms of resistance to the drug are also discussed. © 2010 Japanese Cancer Association.

  14. Exosomes serve as nanoparticles to suppress tumor growth and angiogenesis in gastric cancer by delivering hepatocyte growth factor siRNA.

    PubMed

    Zhang, Haiyang; Wang, Yi; Bai, Ming; Wang, Junyi; Zhu, Kegan; Liu, Rui; Ge, Shaohua; Li, JiaLu; Ning, Tao; Deng, Ting; Fan, Qian; Li, Hongli; Sun, Wu; Ying, Guoguang; Ba, Yi

    2018-03-01

    Exosomes derived from cells have been found to mediate signal transduction between cells and to act as efficient carriers to deliver drugs and small RNA. Hepatocyte growth factor (HGF) is known to promote the growth of both cancer cells and vascular cells, and the HGF-cMET pathway is a potential clinical target. Here, we characterized the inhibitory effect of HGF siRNA on tumor growth and angiogenesis in gastric cancer. In addition, we showed that HGF siRNA packed in exosomes can be transported into cancer cells, where it dramatically downregulates HGF expression. A cell co-culture model was used to show that exosomes loaded with HGF siRNA suppress proliferation and migration of both cancer cells and vascular cells. Moreover, exosomes were able to transfer HGF siRNA in vivo, decreasing the growth rates of tumors and blood vessels. The results of our study demonstrate that exosomes have potential for use in targeted cancer therapy by delivering siRNA. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  15. Ricinus communis-based biopolymer and epidermal growth factor regulations on bone defect repair: A rat tibia model

    NASA Astrophysics Data System (ADS)

    Mendoza-Barrera, C.; Meléndez-Lira, M.; Altuzar, V.; Tomás, S. A.

    2003-01-01

    We report the effect of the addition of an epidermal growth factor to a Ricinus communis-based biopolymer in the healing of a rat tibia model. Bone repair and osteointegration after a period of three weeks were evaluated employing photoacoustic spectroscopy and x-ray diffraction. A parallel study was performed at 1, 2, 3, 4, 5, 6, 7, and 8 weeks with energy dispersive x-ray spectroscopy. We conclude that the use of an epidermal growth factor (group EGF) in vivo accelerates the process of bony repair in comparison with other groups, and that the employment of the Ricinus communis-based biopolymer as a bone substitute decreases bone production.

  16. Magnetic alginate microspheres: system for the position controlled delivery of nerve growth factor.

    PubMed

    Ciofani, Gianni; Raffa, Vittoria; Menciassi, Arianna; Cuschieri, Alfred; Micera, Silvestro

    2009-04-01

    The use of polymeric carriers containing dispersed magnetic nanocrystalline particles for targeted delivery of drugs in clinical practice has attracted the interest of the scientific community. In this paper a system comprised of alginate microparticles with a core of magnetite and carrying nerve growth factor (NGF) is described. The magnetic properties of these microspheres, typical of superparamagnetic materials, allow precise and controlled delivery to the intended tissue environment. Experiments carried out on PC12 cells with magnetic alginate microspheres loaded with NGF have confirmed the induction of cell differentiation which is strongly dependent on the distance from the microsphere cluster. In addition, finite element modelling (FEM) of the release profile from the microspheres in culture, indicated the possibility of creating defined and predictable NGF gradients from the loaded microspheres. These observations on the carriage and release of growth factors by the proposed microparticles open new therapeutic options for both neuronal regeneration and of the development of effective neuronal interfaces.

  17. Assessment of Growth Factors Secreted by Human Breastmilk Mesenchymal Stem Cells.

    PubMed

    Kaingade, Pankaj Mahipatrao; Somasundaram, Indumathi; Nikam, Amar Babaso; Sarang, Shabari Amit; Patel, Jagdish Shantilal

    2016-01-01

    Human breastmilk is a dynamic, multifaceted biological fluid containing nutrients, bioactive substances, and growth factors. It is effective in supporting growth and development of an infant. As breastmilk has been found to possess mesenchymal stem cells, the importance of the components of breastmilk and their physiological roles is increasing day by day. The present study was intended to identify the secretions of growth factors, mainly vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF), from human breastmilk mesenchymal stem cells under basal conditions of in vitro cell culture using synthetic media and human cord serum. The growth factors were analyzed with the enzyme-linked immunosorbent assay technique. The cultured mesenchymal stem cells of breastmilk without serum revealed significant differences in secretions of the VEGF and HGF growth factors (8.55 ± 2.26402 pg/mL and 230.8 ± 45.9861 pg/mL, respectively) compared with mesenchymal stem cells of breastmilk with serum (21.31 ± 4.69 pg/mL and 2,404.42 ± 481.593 pg/mL, respectively). Results obtained from our study demonstrate that both VEGF and HGF are secreted in vitro by human breastmilk mesenchymal stem cells. The roles of VEGF and HGF in surfactant secretion, pulmonary maturation, and neonatal maturity have been well established. Thus, we emphasize that breastmilk-derived MSCs could be a potent therapeutic source in treating neonatal diseases. Besides, due to its immense potency, the study also emphasizes the importance of breastfeeding, which is promoted by organizations like the World Heatlh Organization and UNICEF.

  18. Additive genetic variance and developmental plasticity in growth trajectories in a wild cooperative mammal.

    PubMed

    Huchard, E; Charmantier, A; English, S; Bateman, A; Nielsen, J F; Clutton-Brock, T

    2014-09-01

    Individual variation in growth is high in cooperative breeders and may reflect plastic divergence in developmental trajectories leading to breeding vs. helping phenotypes. However, the relative importance of additive genetic variance and developmental plasticity in shaping growth trajectories is largely unknown in cooperative vertebrates. This study exploits weekly sequences of body mass from birth to adulthood to investigate sources of variance in, and covariance between, early and later growth in wild meerkats (Suricata suricatta), a cooperative mongoose. Our results indicate that (i) the correlation between early growth (prior to nutritional independence) and adult mass is positive but weak, and there are frequent changes (compensatory growth) in post-independence growth trajectories; (ii) among parameters describing growth trajectories, those describing growth rate (prior to and at nutritional independence) show undetectable heritability while associated size parameters (mass at nutritional independence and asymptotic mass) are moderately heritable (0.09 ≤ h(2) < 0.3); and (iii) additive genetic effects, rather than early environmental effects, mediate the covariance between early growth and adult mass. These results reveal that meerkat growth trajectories remain plastic throughout development, rather than showing early and irreversible divergence, and that the weak effects of early growth on adult mass, an important determinant of breeding success, are partly genetic. In contrast to most cooperative invertebrates, the acquisition of breeding status is often determined after sexual maturity and strongly impacted by chance in many cooperative vertebrates, who may therefore retain the ability to adjust their morphology to environmental changes and social opportunities arising throughout their development, rather than specializing early. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  19. The Role of Growth Hormone and Insulin-Like Growth Factor-I in the Liver.

    PubMed

    Takahashi, Yutaka

    2017-07-05

    Adult growth hormone deficiency (GHD) is characterized by metabolic abnormalities associated with visceral obesity, impaired quality of life, and increased mortality. Patients with adult GHD show increased prevalence of non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH), and growth hormone (GH) replacement therapy has been shown to improve these conditions. It has also been demonstrated that a decrease in the GH insulin-like growth factor-I (IGF-I) axis is closely associated with the progression of general NAFLD, suggesting a physiological role of these hormones for the maintenance of the liver. NASH histologically demonstrates inflammation, necrosis, and fibrosis, in addition to steatosis (and is a serious disease because it can progress to liver cirrhosis and hepatocellular carcinoma in a subset of cases). While fibrosis determines the prognosis of the patient, efficacious treatment for fibrosis is crucial; however, it has not yet been established. Recent studies have clarified the essential roles of GH and IGF-I in the liver. GH profoundly reduces visceral fat, which plays an important role in the development of NAFLD. Furthermore, GH directly reduces lipogenesis in the hepatocytes. IGF-I induces cellular senescence and inactivates hepatic stellate cells, therefore ameliorating fibrosis. IGF-I treatment has been shown to improve animal models of NASH and cirrhosis, suggesting potential clinical applications of IGF-I in these conditions. In this review, I will focus on the important roles of GH and IGF-I in the liver, their underlying mechanisms, and their potential therapeutic applications.

  20. Effect of transforming growth factor-beta and growth differentiation factor-5 on proliferation and matrix production by human bone marrow stromal cells cultured on braided poly lactic-co-glycolic acid scaffolds for ligament tissue engineering.

    PubMed

    Jenner, J M G Th; van Eijk, F; Saris, D B F; Willems, W J; Dhert, W J A; Creemers, Laura B

    2007-07-01

    Tissue engineering of ligaments based on biomechanically suitable biomaterials combined with autologous cells may provide a solution for the drawbacks associated with conventional graft material. The aim of the present study was to investigate the contribution of recombinant human transforming growth factor beta 1 (rhTGF-beta1) and growth differentiation factor (GDF)-5, known for their role in connective tissue regeneration, to proliferation and matrix production by human bone marrow stromal cells (BMSCs) cultured onto woven, bioabsorbable, 3-dimensional (3D) poly(lactic-co-glycolic acid) scaffolds. Cells were cultured for 12 days in the presence or absence of these growth factors at different concentrations. Human BMSCs attached to the suture material, proliferated, and synthesized extracellular matrix rich in collagen type I and collagen III. No differentiation was demonstrated toward cartilage or bone tissue. The addition of rhTGF-beta1 (1-10 ng/mL) and GDF-5 (10-100 ng/mL) increased cell content (p < 0.05), but only TGF-beta1 also increased total collagen production (p < 0.05) and collagen production per cell, which is a parameter indicating differentiation. In conclusion, stimulation with rhTGF-beta1, and to a lesser extent with GDF-5, can modulate human BMSCs toward collagenous soft tissue when applied to a 3D hybrid construct. The use of growth factors could play an important role in the improvement of ligament tissue engineering.

  1. Old friends in new constellations--the hematopoetic growth factors G-CSF, GM-CSF, and EPO for the treatment of neurological diseases.

    PubMed

    Maurer, M H; Schäbitz, W-R; Schneider, A

    2008-01-01

    Currently, growth factors which have been identified in hematopoiesis and angiogenesis are re-considered as therapeutical agents in a number of neurological diseases, mainly neurodegenerative disorders like Parkinson's Disease, amyotrophic lateral sclerosis (ALS), or cerebrovascular events such as stroke. Among these growth factors, erythropoietin (EPO) and granulocyte colony-stimulating growth factor (G-CSF) are the most prominent. With regard to neurological disease, EPO has been tested in clinical trials for potential use in stroke, schizophrenia, and addiction, G-CSF is currently under clinical investigation for stroke treatment. The major advantage of these growth factors is their well-described pharmacological behavior and their clinical use over several years. A number of mechanisms of action in the CNS have been identified that are probably important for the beneficial action of these factors in animal models of disease, the most relevant relating to neuroprotection, neuroplasticity and stem cell growth and differentiation. In this review, we will discuss the current efforts and prerequisites of novel growth factor therapies for neurodegenerative diseases with regard to their possible mechanism of action on the molecular level and their effects on brain-derived stem cell populations. Additionally, we will describe the necessities for future research before such therapies can be envisioned.

  2. Release of Growth Factors into Root Canal by Irrigations in Regenerative Endodontics.

    PubMed

    Zeng, Qian; Nguyen, Sean; Zhang, Hongming; Chebrolu, Hari Priya; Alzebdeh, Dalia; Badi, Mustafa A; Kim, Jong Ryul; Ling, Junqi; Yang, Maobin

    2016-12-01

    The aim of this study was to investigate the release of growth factors into root canal space after the irrigation procedure of regenerative endodontic procedure. Sixty standardized root segments were prepared from extracted single-root teeth. Nail varnish was applied to all surfaces except the root canal surface. Root segments were irrigated with 1.5% NaOCl + 17% EDTA, 2.5% NaOCl + 17% EDTA, 17% EDTA, or deionized water. The profile of growth factors that were released after irrigation was studied by growth factor array. Enzyme-linked immunosorbent assay was used to validate the release of transforming growth factor (TGF)-β1 and basic fibroblast growth factor (bFGF) at 4 hours, 1 day, and 3 days after irrigation. The final concentrations were calculated on the basis of the root canal volume measured by cone-beam computed tomography. Dental pulp stem cell migration on growth factors released from root segments was measured by using Transwell assay. Total of 11 of 41 growth factors were detected by growth factors array. Enzyme-linked immunosorbent assay showed that TGF-β1 was released in all irrigation groups. Compared with the group with 17% EDTA (6.92 ± 4.49 ng/mL), the groups with 1.5% NaOCl + 17% EDTA and 2.5% NaOCl + 17% EDTA had significantly higher release of TGF-β1 (69.04 ± 30.41 ng/mL and 59.26 ± 3.37 ng/mL, respectively), with a peak release at day 1. The release of bFGF was detected at a low level in all groups (0 ng/mL to 0.43 ± 0.22 ng/mL). Migration assay showed the growth factors released from root segments induced dental pulp stem cell migration. The root segment model in present study simulated clinical scenario and indicated that the current irrigation protocol released a significant amount of TGF-β1 but not bFGF. The growth factors released into root canal space induced dental pulp stem cell migration. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  3. Risk factors affecting human traumatic tympanic membrane perforation regeneration therapy using fibroblast growth factor-2.

    PubMed

    Lou, Zhengcai; Yang, Jian; Tang, Yongmei; Xiao, Jian

    2015-01-01

    The use of growth factors to achieve closure of human traumatic tympanic membrane perforations (TMPs) has recently been demonstrated. However, pretreatment factors affecting healing outcomes have seldom been discussed. The objective of this study was to evaluate pretreatment factors contributing to the success or failure of healing of TMPs using fibroblast growth factor-2 (FGF-2). A retrospective cohort study of 99 patients (43 males, 56 females) with traumatic TMPs who were observed for at least 6 months after FGF-2 treatment between March 2011 and December 2012. Eleven factors considered likely to affect the outcome of perforation closure were evaluated statistically using univariate and multivariate logistic regression analysis. Each traumatic TMP was treated by direct application of FGF-2. Complete closure versus failure to close. In total, 99 patients were analyzed. The total closure rate was 92/99 (92.9%) at 6 months; the mean closure time was 10.59 ±  6.81 days. The closure rate did not significantly differ between perforations with or without inverted edges (100.0% vs. 91.4%, p = 0.087), among different size groups (p = 0.768), or among different periods of exposure to injury (p = 0.051). However, the closure rate was significantly different between the high- and low-dose FGF-2 groups (85.0% vs. 98.3%, p = 0.010) and between perforations where the umbo or malleus was or was not involved in perforation (85.4% vs. 98.3%, p = 0.012). Additionally, univariate logistic regression analysis tests showed that it was difficult to achieve healing of these perforations with a history of chronic otitis media or residual TM calcification (p = 0.006), the umbo or malleus was involved in perforation (p = 0.038), and with a high dose of FGF-2 (p = 0.035) compared with control groups. Multivariate logistic regression analysis showed that only a history of chronic otitis media and residual TM calcification and perforation close to the

  4. The Growth and Protein Expression of Inflammatory Bowel Disease-Associated Campylobacter concisus Is Affected by the Derivatives of the Food Additive Fumaric Acid.

    PubMed

    Ma, Rena; Liu, Fang; Yap, Soe F; Lee, Hoyul; Leong, Rupert W; Riordan, Stephen M; Grimm, Michael C; Zhang, Li

    2018-01-01

    Inflammatory bowel diseases (IBD) are chronic inflammatory conditions of the gastrointestinal tract with multifactorial etiology. Both dietary factors and the microbe Campylobacter concisus have been found to be associated with the condition. The current study examined the effects of sodium fumarate, a neutralized product of the food additives fumaric acid and monosodium fumarate when in the intestinal environment, on the growth of C. concisus to determine the effects of these food additives on IBD-associated bacterial species. Through culture methods and quantification, it was found that neutralized fumaric acid, neutralized monosodium fumarate, and sodium fumarate increased the growth of C. concisus , with the greatest increase in growth at a concentration of 0.4%. Further examination of 50 C. concisus strains on media with added sodium fumarate showed that greatest growth was also achieved at a concentration of 0.4%. At a concentration of 2% sodium fumarate, all strains examined displayed less growth in comparison with those cultured on media without sodium fumarate. Using mass spectrometry, multiple C. concisus proteins showed significant differential expression when cultured on media with and without 0.4% sodium fumarate. The findings presented suggest that patients with IBD should consider avoiding excessive consumption of foods with fumaric acid or its sodium salts, and that the addition of 0.4% sodium fumarate alone to media may assist in the isolation of C. concisus from clinical samples.

  5. Nucleation and growth of chimney pores during electron-beam additive manufacturing

    DOE PAGES

    Cordero, Zachary C.; Dinwiddie, Ralph B.; Immel, David; ...

    2016-12-05

    The nucleation and growth of chimney pores during powder-bed, electron-beam additive manufacturing is investigated using in-situ infrared thermography as well as microcomputed tomography of as-printed parts. The pores are found to nucleate at dimples on the part s surface, clearly demonstrating how process parameters can affect surface roughness, which can in turn affect the internal defect structure in an additive manufactured part. Based on the results of this study, several strategies for suppressing the formation of chimney pores are discussed.

  6. Keratinocyte response to immobilized growth factors for enhanced dermal wound healing

    NASA Astrophysics Data System (ADS)

    Stefonek-Puccinelli, Tracy Jane

    Chronic wounds cost billions of dollars per year to treat and wound care is limited to ineffective and/or expensive options. Chronic wounds are characterized by a failure to reepithelialize, as well as deficiencies in growth factors, such as epidermal growth factor (EGF) and insulin-like growth factor-1 (IGF-1), normally present during wound healing. Our system described herein begins to tackle the problems associated with designing bioactive materials for chronic wound healing applications. We show that we can induce accelerated keratinocyte migration with photo-immobilized EGF and further control migration speed through the culture of cells on different types of gradient patterns of EGF. We also successfully immobilized IGF-1 while retaining its bioactivity, and further showed it induces directed keratinocyte migration, although not as potently as immobilized EGF. Potential synergy between co-immobilized IGF-1 and EGF was also investigated, although EGF continued to dominate the cellular response, and no significant increase in cell migration was achieved via the addition of IGF-1 to the system. To further understand cellular response to our immobilized growth factors, we investigated keratinocyte signaling and function in response to changes in EGF presentation. It was found that immobilized and soluble EGF can play different, yet complementary, roles in regulating keratinocyte function. Specifically, keratinocytes responded to immobilized EGF with high EGF receptor (EGFR) activation, accompanied by low proliferation and high migratory activity. In contrast, keratinocytes treated with soluble EGF displayed a highly proliferative, rather than migratory, phenotype. We then transitioned our photo-immobilization techniques to materials that may be more suitable as a wound dressing, such as silk fibroin films. Silk fibroin is a natural fiber with many desirable qualities for a biomaterial including high strength and elasticity, biocompatibility, a beta

  7. Neurotrophic factors switch between two signaling pathways that trigger axonal growth.

    PubMed

    Paveliev, Mikhail; Lume, Maria; Velthut, Agne; Phillips, Matthew; Arumäe, Urmas; Saarma, Mart

    2007-08-01

    Integration of multiple inputs from the extracellular environment, such as extracellular matrix molecules and growth factors, is a crucial process for cell function and information processing in multicellular organisms. Here we demonstrate that co-stimulation of dorsal root ganglion neurons with neurotrophic factors (NTFs) - glial-cell-line-derived neurotrophic factor, neurturin or nerve growth factor - and laminin leads to axonal growth that requires activation of Src family kinases (SFKs). A different, SFK-independent signaling pathway evokes axonal growth on laminin in the absence of the NTFs. By contrast, axonal branching is regulated by SFKs both in the presence and in the absence of NGF. We propose and experimentally verify a Boolean model of the signaling network triggered by NTFs and laminin. Our results demonstrate that NTFs provide an environmental cue that triggers a switch between separate pathways in the cell signaling network.

  8. Interleukin-Driven Insulin-Like Growth Factor Promotes Prostatic Inflammatory Hyperplasia

    PubMed Central

    Hahn, Alana M.; Myers, Jason D.; McFarland, Eliza K.; Lee, Sanghee

    2014-01-01

    Prostatic inflammation is of considerable importance to urologic research because of its association with benign prostatic hyperplasia and prostate cancer. However, the mechanisms by which inflammation leads to proliferation and growth remain obscure. Here, we show that insulin-like growth factors (IGFs), previously known as critical developmental growth factors during prostate organogenesis, are induced by inflammation as part of the proliferative recovery to inflammation. Using genetic models and in vivo IGF receptor blockade, we demonstrate that the hyperplastic response to inflammation depends on interleukin-1–driven IGF signaling. We show that human prostatic hyperplasia is associated with IGF pathway activation specifically localized to foci of inflammation. This demonstrates that mechanisms of inflammation-induced epithelial proliferation and hyperplasia involve the induction of developmental growth factors, further establishing a link between inflammatory and developmental signals and providing a mechanistic basis for the management of proliferative diseases by IGF pathway modulation. PMID:25292180

  9. Interplay between pro-inflammatory cytokines and growth factors in depressive illnesses

    PubMed Central

    Audet, Marie-Claude; Anisman, Hymie

    2013-01-01

    The development of depressive disorders had long been attributed to monoamine variations, and pharmacological treatment strategies likewise focused on methods of altering monoamine availability. However, the limited success achieved by treatments that altered these processes spurred the search for alternative mechanisms and treatments. Here we provide a brief overview concerning a possible role for pro-inflammatory cytokines and growth factors in major depression, as well as the possibility of targeting these factors in treating this disorder. The data suggest that focusing on one or another cytokine or growth factor might be counterproductive, especially as these factors may act sequentially or in parallel in affecting depressive disorders. It is also suggested that cytokines and growth factors might be useful biomarkers for individualized treatments of depressive illnesses. PMID:23675319

  10. Connective tissue growth factor immunohistochemical expression is associated with gallbladder cancer progression.

    PubMed

    Garcia, Patricia; Leal, Pamela; Alvarez, Hector; Brebi, Priscilla; Ili, Carmen; Tapia, Oscar; Roa, Juan C

    2013-02-01

    Gallbladder cancer (GBC) is an aggressive neoplasia associated with late diagnosis, unsatisfactory treatment, and poor prognosis. Molecular mechanisms involved in GBC pathogenesis remain poorly understood. Connective tissue growth factor (CTGF) is thought to play a role in the pathologic processes and is overexpressed in several human cancers, including GBC. No information is available about CTGF expression in early stages of gallbladder carcinogenesis. Objective.- To evaluate the expression level of CTGF in benign and malignant lesions of gallbladder and its correlation with clinicopathologic features and GBC prognosis. Connective tissue growth factor protein was examined by immunohistochemistry on tissue microarrays containing tissue samples of chronic cholecystitis (n = 51), dysplasia (n = 15), and GBC (n = 169). The samples were scored according to intensity of staining as low/absent and high CTGF expressers. Statistical analysis was performed using the χ(2) test or Fisher exact probability test with a significance level of P < .05. Survival analysis was assessed by the Kaplan-Meier method and the log-rank test. Connective tissue growth factor expression showed a progressive increase from chronic cholecystitis to dysplasia and then to early and advanced carcinoma. Immunohistochemical expression (score ≥2) was significantly higher in advanced tumors, in comparison with chronic cholecystitis (P < .001) and dysplasia (P = .03). High levels of CTGF expression correlated with better survival (P = .04). Our results suggest a role for CTGF in GBC progression and a positive association with better prognosis. In addition, they underscore the importance of considering the involvement of inflammation on GBC development.

  11. Vascular Endothelial Growth Factor Modulates Skeletal Myoblast Function

    PubMed Central

    Germani, Antonia; Di Carlo, Anna; Mangoni, Antonella; Straino, Stefania; Giacinti, Cristina; Turrini, Paolo; Biglioli, Paolo; Capogrossi, Maurizio C.

    2003-01-01

    Vascular endothelial growth factor (VEGF) expression is enhanced in ischemic skeletal muscle and is thought to play a key role in the angiogenic response to ischemia. However, it is still unknown whether, in addition to new blood vessel growth, VEGF modulates skeletal muscle cell function. In the present study immunohistochemical analysis showed that, in normoperfused mouse hindlimb, VEGF and its receptors Flk-1 and Flt-1 were expressed mostly in quiescent satellite cells. Unilateral hindlimb ischemia was induced by left femoral artery ligation. At day 3 and day 7 after the induction of ischemia, Flk-1 and Flt-1 were expressed in regenerating muscle fibers and VEGF expression by these fibers was markedly enhanced. Additional in vitro experiments showed that in growing medium both cultured satellite cells and myoblast cell line C2C12 expressed VEGF and its receptors. Under these conditions, Flk-1 receptor exhibited constitutive tyrosine phosphorylation that was increased by VEGF treatment. During myogenic differentiation Flk-1 and Flt-1 were down-regulated. In a modified Boyden Chamber assay, VEGF enhanced C2C12 myoblasts migration approximately fivefold. Moreover, VEGF administration to differentiating C2C12 myoblasts prevented apoptosis, while inhibition of VEGF signaling either with selective VEGF receptor inhibitors (SU1498 and CB676475) or a neutralizing Flk-1 antibody, enhanced cell death approximately 3.5-fold. Finally, adenovirus-mediated VEGF165 gene transfer inhibited ischemia-induced apoptosis in skeletal muscle. These results support a role for VEGF in myoblast migration and survival, and suggest a novel autocrine role of VEGF in skeletal muscle repair during ischemia. PMID:14507649

  12. Galangin inhibits human osteosarcoma cells growth by inducing transforming growth factor-β1-dependent osteogenic differentiation.

    PubMed

    Liu, Chunhong; Ma, Mingming; Zhang, Junde; Gui, Shaoliu; Zhang, Xiaohai; Xue, Shuangtao

    2017-05-01

    Osteosarcoma is the most common primary malignancy of the musculoskeletal system, and is associated with excessive proliferation and poor differentiation of osteoblasts. Currently, despite the use of traditional chemotherapy and radiotherapy, no satisfactory and effective agent has been developed to treat the disease. Herein, we found that a flavonoid natural product, galangin, could significantly attenuate human osteosarcoma cells proliferation, without causing obvious cell apoptosis. Moreover, galangin enhanced the expression of osteoblast differentiation markers (collagen type I, alkaline phosphatase, osteocalcin and osteopontin) remarkably and elevated the alkaline phosphatase activity in human osteosarcoma cells. And galangin could also attenuated osteosarcoma growth in vivo. These bioactivities of galangin resulted from its selective activation of the transforming growth factor (TGF)-β1/Smad2/3 signaling pathway, which was demonstrated by pathway blocking experiments. These findings suggested that galangin could be a promising agent to treat osteosarcoma. In addition, targeting TGF-β1 to induce osteogenic differentiation might represent a novel therapeutic strategy to treat osteosarcoma with minimal side effects. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  13. Targeting the fibroblast growth factor receptors for the treatment of cancer.

    PubMed

    Lemieux, Steven M; Hadden, M Kyle

    2013-06-01

    Receptor tyrosine kinases (RTKs) are transmembrane proteins that play a critical role in stimulating signal transduction cascades to influence cell proliferation, growth, and differentiation and they have also been shown to promote angiogenesis when they are up-regulated or mutated. For this reason, their dysfunction has been implicated in the development of human cancer. Over the past decade, much attention has been devoted to developing inhibitors and antibodies against several classes of RTKs, including vascular endothelial growth factor receptors (VEGFRs), epidermal growth factor receptors (EGFRs), and platelet-derived growth factor receptors (PDGFRs). More recently, interest in the fibroblast growth factor receptor (FGFR) class of RTKs as a drug target for the treatment of cancer has emerged. Signaling through FGFRs is critical for normal cellular function and their dysregulation has been linked to various malignancies such as breast and prostate cancer. This review will focus on the current state of both small molecules and antibodies as FGFR inhibitors to provide insight into their development and future potential as anti-cancer agents.

  14. Concentration of platelets and growth factors in platelet-rich plasma from Goettingen minipigs.

    PubMed

    Jungbluth, Pascal; Grassmann, Jan-Peter; Thelen, Simon; Wild, Michael; Sager, Martin; Windolf, Joachim; Hakimi, Mohssen

    2014-01-01

    In minipigs little is known about the concentration of growth factors in plasma, despite their major role in several patho-physiological processes such as healing of fractures. This prompted us to study the concentration of platelets and selected growth factors in plasma and platelet-rich plasma (PRP) preparation of sixteen Goettingen minipigs. Platelet concentrations increased significantly in PRP in comparison to native blood plasma. Generally, significant increase in the concentration of all growth factors tested was observed in the PRP in comparison to the corresponding plasma or serum. Five of the plasma samples examined contained detectable levels of bone morphogenic protein 2 (BMP-2) whereas eleven of the plasma or serum samples contained minimal amounts of vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF-bb) respectively. On the other hand variable concentrations of bone morphogenic protein 7 (BMP-7) and transforming growth factor β1 (TGF-β1) were measured in all plasma samples. In contrast, all PRP samples contained significantly increased amounts of growth factors. The level of BMP-2, BMP-7, TGF-β1, VEGF and PDGF-bb increased by 17.6, 1.5, 7.1, 7.2 and 103.3 fold, in comparison to the corresponding non-enriched preparations. Moreover significant positive correlations were found between platelet count and the concentrations of BMP-2 (r=0.62, p<0.001), TGF-β1 (r=0.85, p<0.001), VEGF (r=0.46, p<0.01) and PDGF-bb (r=0.9, p<0.001). Our results demonstrate that selected growth factors are present in the platelet-rich plasma of minipigs which might thus serve as a source of autologous growth factors.

  15. [Therapeutic use of hematopoietic growth factors. II. GM-CSF and G-CSF].

    PubMed

    Royer, B; Arock, M

    1998-01-01

    The second part of this review on haematopoietic growth factors is focused on the therapeutic use of GM-CSF and G-CSF. Such therapeutic applications have raised very great hopes for clinical haematology. However, it should not be forgotten that these haematopoietic growth factors, which are very costly, are powerful two-edged weapons capable of triggering a cascade of reactions, and have a field of activity that often goes beyond the single highly specific property which it is hoped they possess. The risks and costs of their use are currently being evaluated. Waited developments concerning these molecules focus on three axes: a best use of factors already commercialized, especially concerning adaptation of posologies and new indications, the development of hybrid molecules from already known haematopoietic growth factors, possessing the advantages of respective factors, but not their disadvantages, the discovery of new haematopoietic growth factors with potential therapeutic application.

  16. Ultrastructure and growth factor content of equine platelet-rich fibrin gels.

    PubMed

    Textor, Jamie A; Murphy, Kaitlin C; Leach, J Kent; Tablin, Fern

    2014-04-01

    To compare fiber diameter, pore area, compressive stiffness, gelation properties, and selected growth factor content of platelet-rich fibrin gels (PRFGs) and conventional fibrin gels (FGs). PRFGs and conventional FGs prepared from the blood of 10 healthy horses. Autologous fibrinogen was used to form conventional FGs. The PRFGs were formed from autologous platelet-rich plasma of various platelet concentrations (100 × 10³ platelets/μL, 250 × 10³ platelets/μL, 500 × 10³ platelets/μL, and 1,000 × 10³ platelets/μL). All gels contained an identical fibrinogen concentration (20 mg/mL). Fiber diameter and pore area were evaluated with scanning electron microscopy. Maximum gelation rate was assessed with spectrophotometry, and gel stiffness was determined by measuring the compressive modulus. Gel weights were measured serially over 14 days as an index of contraction (volume loss). Platelet-derived growth factor-BB and transforming growth factor-β1 concentrations were quantified with ELISAs. Fiber diameters were significantly larger and mean pore areas were significantly smaller in PRFGs than in conventional FGs. Gel weight decreased significantly over time, differed significantly between PRFGs and conventional FGs, and was significantly correlated with platelet concentration. Platelet-derived growth factor-BB and transforming growth factor-β1 concentrations were highest in gels and releasates derived from 1,000 × 10³ platelets/μL. The inclusion of platelets in FGs altered the architecture and increased the growth factor content of the resulting scaffold. Platelets may represent a useful means of modifying these gels for applications in veterinary and human regenerative medicine.

  17. Efficacy of a Single Dose of Basic Fibroblast Growth Factor: Clinical Observation for 1 Year.

    PubMed

    Suzuki, Hirotaka; Makiyama, Kiyoshi; Hirai, Ryoji; Matsuzaki, Hiroumi; Furusaka, Toru; Oshima, Takeshi

    2016-11-01

    Basic fibroblast growth factor promotes wound healing by accelerating healthy granulation and epithelialization. However, the duration of the effects of a single intracordal injection of basic fibroblast growth factor has not been established, and administration intervals and timing have yet to be standardized. Here, we administered a single injection to patients with insufficient glottic closure and conducted follow-up examinations with high-speed digital imaging to determine the duration of the treatment response. Case series. For treatment, 20 µg/mL recombinant human basic fibroblast growth factor was injected into two vocal cords. The following examinations were performed before the procedure and at 3-month intervals for 12 months starting at 1 month postinjection: Grade, Roughness, Breathiness, Asthenia, and Strain (GRBAS) scale assessment, maximum phonation time, acoustic analysis, high-speed digital imaging, glottal wave analysis, and kymographic analysis. Postinjection, the GRBAS scale score decreased, and the maximum phonation time was prolonged. In addition, the mean minimum glottal area and mean minimum glottal distance decreased. These changes were significant at 12 months postinjection compared with preinjection. However, there were no significant changes in the vibrations of the vocal cord margins. The intracordal injection of basic fibroblast growth factor improved insufficient glottic closure without reducing the vibrations of the vocal cord margins. This effect remained evident at 12 months postinjection. A single injection can be expected to yield a sufficient and persistent long-term effect. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  18. Blockade of vascular endothelial growth factor receptor and epidermal growth factor receptor signaling for therapy of metastatic human pancreatic cancer.

    PubMed

    Baker, Cheryl H; Solorzano, Carmen C; Fidler, Isaiah J

    2002-04-01

    We determined whether concurrent blockage of vascular endothelial growth factor (VEGF) receptor and epidermal growth factor (EGF) receptor signaling by two novel tyrosine kinase inhibitors, PTK 787 and PKI 166, respectively, can inhibit angiogenesis and, hence, the growth and metastasis of human pancreatic carcinoma in nude mice. Highly metastatic human pancreatic carcinoma L3.6pl cells were injected into the pancreas of nude mice. Seven days later, groups of mice began receiving oral doses of PTK 787 and PKI 166 three times weekly. Some groups of mice also received i.p. injections of gemcitabine twice a week. The mice were necropsied when the control mice became moribund. Treatment with PTK 787 and PKI 166, with gemcitabine alone, or with the combination of PTK 787, PKI 166, and gemcitabine produced 69, 50, and 97% reduction in the volume of pancreatic tumors, respectively. Administration of protein tyrosine kinase inhibitors and gemcitabine also significantly decreased the incidence of lymph node and liver metastasis. The therapeutic efficacy directly correlated with a decrease in circulating proangiogenic molecules (VEGF, interleukin-8), a decrease in microvessel density, a decrease in proliferating cell nuclear antigen staining, and an increase in apoptosis of tumor cells and endothelial cells. Therapies produced by combining gemcitabine with either PKI 166 or PTK 787 were similar to those produced by combining gemcitabine with both PKI 166 and PTK 787. These results suggest that blockade of either epidermal growth factor receptor or VEGF receptor signaling combined with chemotherapy provides an effective approach to the therapy of pancreatic cancer.

  19. The growth rates of KDP crystals in solutions with potassium permanganate additives

    NASA Astrophysics Data System (ADS)

    Egorova, A. E.; Vorontsov, D. A.; Nezhdanov, A. V.; Noskova, A. N.; Portnov, V. N.

    2017-01-01

    We have found that growth of the {101} faces of a KDP (KH2PO4) crystal is suppressed, and the growth rate of the {100} faces passes through the maximum with increasing addition of KMnO4 to a solution with pH=4.7. We have concluded that the [MnH2PO4]2+ complex and MnO2 particles affect the growth kinetics. The X-ray and electronic paramagnetic resonance data show that manganese is incorporated into the crystal in the form of Mn3+ and Mn4+. The local excess of a positive charge in the area with incorporated [MnH2PO4]2+ complex can be compensated by the shift of the hydrogen atoms in the KDP structure.

  20. Insulin-like growth factor-1, insulin-like growth factor-binding protein-3, growth hormone, and mammographic density in the Nurses' Health Studies.

    PubMed

    Rice, Megan S; Tworoger, Shelley S; Rosner, Bernard A; Pollak, Michael N; Hankinson, Susan E; Tamimi, Rulla M

    2012-12-01

    Higher circulating insulin-like growth factor I (IGF-1) levels have been associated with higher mammographic density among women in some, but not all studies. Also, few studies have examined the association between mammographic density and circulating growth hormone (GH) in premenopausal women. We conducted a cross-sectional study among 783 premenopausal women and 436 postmenopausal women who were controls in breast cancer case-control studies nested in the Nurses' Health Study (NHS) and NHSII. Participants provided blood samples in 1989-1990 (NHS) or in 1996-1999 (NHSII), and mammograms were obtained near the time of blood draw. Generalized linear models were used to assess the associations of IGF-1, IGF-binding protein-3 (IGFBP-3), IGF-1:IGFBP-3 ratio, and GH with percent mammographic density, total dense area, and total non-dense area. Models were adjusted for potential confounders including age and body mass index (BMI), among others. We also assessed whether the associations varied by age or BMI. In both pre- and postmenopausal women, percent mammographic density was not associated with plasma levels of IGF-1, IGFBP-3, or the IGF-1:IGFBP-3 ratio. In addition, GH was not associated with percent density among premenopausal women in the NHSII. Similarly, total dense area and non-dense area were not significantly associated with any of these analytes. In postmenopausal women, IGF-1 was associated with higher percent mammographic density among women with BMI <25 kg/m(2), but not among overweight/obese women. Overall, plasma IGF-1, IGFBP-3, and GH levels were not associated with mammographic density in a sample of premenopausal and postmenopausal women.

  1. A virally inactivated functional growth factor preparation from human platelet concentrates.

    PubMed

    Su, C-Y; Kuo, Y P; Lin, Y C; Huang, C-T; Tseng, Y H; Burnouf, T

    2009-08-01

    Human platelet growth factors (HPGF) are essential for tissue regeneration and may replace fetal bovine serum (FBS) in cell therapy. No method for the manufacture of standardized virally inactivated HPGF has been developed yet. Platelet concentrates (PC) were subjected to solvent/detergent (S/D) treatment (1% TnBP/1% Triton X-45), oil extraction, hydrophobic interaction chromatography and sterile filtration. Platelet-derived growth factor (PDGF)-AB, -BB and -AA, transforming growth factor-beta1 (TGF-beta1), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1) and vascular endothelium growth factor (VEGF) were measured by ELISA. Composition in proteins and lipids was determined, protein profiles were obtained by SDS-PAGE, and TnBP and Triton X-45 were assessed by gas chromatography and high-performance liquid chromatography, respectively. Cell growth promoting activity of HPGF was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay using human embryonic kidney (HEK293A) fibroblast and Statens Seruminstitute rabbit corneal (SIRC) epithelial cell lines. The GF preparation contained a mean of 16.66, 2.04, 1.53, 72.19, 0.33, 48.59 and 0.44 ng/ml of PDGF-AB, -BB, -AA, TGF-beta1, EGF, IGF-1 and VEGF, respectively. The protein profile was typical of platelet releasates and had less than 2 p.p.m. of residual S/D agents. MTS assay of HEK293A and SIRC cultures showed that the GF preparation at 10% and 0.1% (v/v), respectively, could successfully replace 10% FBS for cell proliferation. Cell-stimulating activity of HPGF on HEK293A was over twice that of PC releasates. STANDARDIZED and functional virally inactivated HPGF can be prepared from human PC for possible applications in cell therapy and regenerative medicine.

  2. Sustained release of nerve growth factor from biodegradable polymer microspheres.

    PubMed

    Camarata, P J; Suryanarayanan, R; Turner, D A; Parker, R G; Ebner, T J

    1992-03-01

    Although grafted adrenal medullary tissue to the striatum has been used both experimentally and clinically in parkinsonism, there is a definite need to augment long-term survival. Infusion of nerve growth factor (NGF) or implantation of NGF-rich tissue into the area of the graft prolongs survival and induces differentiation into neural-like cells. To provide for prolonged, site-specific delivery of this growth factor to the grafted tissue in a convenient manner, we fabricated biodegradable polymer microspheres of poly(L-lactide)co-glycolide (70:30) containing NGF. Biologically active NGF was released from the microspheres, as assayed by neurite outgrowth in a dorsal root ganglion tissue culture system. Anti-NGF could block this outgrowth. An enzyme-linked immunosorbent assay detected NGF still being released in vitro for longer than 5 weeks. In vivo immunohistochemical studies showed release over a 4.5-week period. This technique should prove useful for incorporating NGF and other growth factors into polymers and delivering proteins and other macromolecules intracerebrally over a prolonged time period. These growth factor-containing polymer microspheres can be used in work aimed at prolonging graft survival, treating experimental Alzheimer's disease, and augmenting peripheral nerve regeneration.

  3. Concentrated Growth Factor Enhanced Fat Graft Survival: A Comparative Study.

    PubMed

    Hu, Yun; Jiang, Yichen; Wang, Muyao; Tian, Weidong; Wang, Hang

    2018-06-08

    Concentrated growth factors (CGFs) belong to a new generation biomaterials that concentrate large number of growth factors and CD34 stem cells in small volume of plasma. The purpose of this study was to evaluate the impact of the new technique, CGF, on fat graft survival, which compared with platelet-rich plasma (PRP) and platelet-rich fibrin (PRF). Nude mice received fat graft were divided into PRP group, PRF group, CGF group, and saline. The grafts were volumetrically and histologically evaluated at 4, 8, and 12 weeks after fat grafting. In vitro growth factor levels in PRP, PRF, and CGF were compared using enzyme-linked immunoassay method. Cell count and real-time polymerase chain reaction were used to evaluate the impact of CGF in medium on human adipose-derived stem cell (hADSC) proliferation and vascular differentiation, respectively. Fat graft weight was significantly higher in the CGF group than those in the other groups, and histologic evaluation revealed greater vascularity, fewer cysts, and less fibrosis. Adding CGF to the medium maximally promoted hADSC proliferation and expressing vascular endothelial growth factor and PECAM-1. In this preliminary study, CGF treatment improved the survival and quality of fat grafts.

  4. Strategies for minimizing complications of neutropenia: prophylactic myeloid growth factors or antibiotics.

    PubMed

    Wingard, John R; Elmongy, Mohamed

    2009-11-01

    Chemotherapy-induced myelosuppression is a major complication of chemotherapy regimens used to treat solid tumors and lymphomas. Myelosuppression is frequently accompanied by neutropenic fever and other complications and threatens the ability to maintain chemotherapy dose intensity. Two prophylaxis strategies have been evaluated to mitigate the infectious complications of myelosuppression: myeloid growth factors and antibiotic. Clinical trials and meta-analyses of trial data indicate substantial benefit to these agents in selected patients. Each type of prophylaxis has advantages and disadvantages. Additional studies are needed to optimize how these are employed in clinical practice.

  5. Silver Nanocube and Nanobar Growth via Anisotropic Monomer Addition and Particle Attachment Processes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiao, Dongdong; Wu, Zhigang; Song, Miao

    Understanding the growth mechanism of noble metal nanocrystals during solution synthesis is of significant importance for shape and property control. However, much remains unknown about the growth pathways of metal nanoparticles due to lack of direct observation. Using an in-situ transmission electron microscopy technique, we directly observed Ag nanocube and nanobar growth in aqueous solution through both classical monomer-by-monomer addition and non-classical particle attachment processes. During the particle attachment process, Ag nanocubes and nanobars formed via both oriented and non-oriented attachment. Our calculations, along with dynamics of the observed attachment, showed that van der Waals force overcame hydrodynamic and frictionmore » forces and drove the particles toward each other. During classical growth, an anisotropic growth was also revealed, and the resulting unsymmetrical shape constituted an intermediate state for Ag nanocube growth. We hypothesized that the temporary symmetry breaking resulted from different growth rates on {001} surfaces due to a local surface concentration variation caused by the imbalance between the consumption of Ag+ near the surface and the diffusion of Ag+ from bulk to surface.« less

  6. Platelet Activating Factor: A Growth Factor for Breast Cancer

    DTIC Science & Technology

    2006-09-01

    synthase (ADS) increases ether lipid content, growth and PAF synthesis in MCF-7 cells. 4. Eicosapentaenoic acid (EPA) inhibits the synthesis of PAF...Schmitt, J. D., Bullock, B. C. Wykle, R. L. Reacylation of platelet activating factor with eicosapentaenoic acid in fish-oil-enriched monkey...breast cancer. Recent studies have shown that the ratio of two families of essential fatty acids is important in regulating many cellular processes

  7. Role of Fibroblast Growth Factor Binding Protein-1 in Mammary Development and Tumorigenesis

    DTIC Science & Technology

    2009-10-01

    AD_________________ Award Number: W81XWH-06-1-0763 TITLE: Role of Fibroblast Growth Factor ...2009 4. TITLE AND SUBTITLE Role of Fibroblast Growth Factor Binding Protein-1 in Mammary Development 5a. CONTRACT NUMBER and Tumorigenesis...Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS Fibroblast Growth Factor Binding Protein-1

  8. ROLES OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF-A) IN MEDIATION OF DIOXIN (TCDD)-INDUCED DELAYS IN DEVELOPMENT OF THE MOUSE MAMMARY GLAND

    EPA Science Inventory

    Roles of Epidermal Growth Factor (EGF) and Transforming Growth Factor-alpha (TGF-a) in Mediation of Dioxin (TCDD)-Induced Delays in Development of the Mouse Mammary Gland.
    Suzanne E. Fenton, Barbara Abbott, Lamont Bryant, and Angela Buckalew. U.S. EPA, NHEERL, Reproductive Tox...

  9. Novel Growth Factor as Prognostic Marker for Estrogen-Independence in Breast Cancer

    DTIC Science & Technology

    2002-08-01

    factor (PCDGF, also known as progranulin ) is a novel autocrine growth factor shown to be overexpressed and to be mitogenic in human breast cancer cell...kDa glycoprotein originally purified from the highly tumorigenic mouse teratoma-derived cell line PC (1, 2). PCDGF (also known as progranulin ) is the...requirement for the insulin-like growth factor 1 receptor for growth in vitro. J Biol Chem, 273: 20078-20083, 1998. 6. He, Z. and Bateman, A. Progranulin gene

  10. Plant-Produced Human Recombinant Erythropoietic Growth Factors Support Erythroid Differentiation In Vitro

    PubMed Central

    Musiychuk, Konstantin; Sivalenka, Rajarajeswari; Jaje, Jennifer; Bi, Hong; Flores, Rosemary; Shaw, Brenden; Jones, R. Mark; Golovina, Tatiana; Schnipper, Jacob; Khandker, Luipa; Sun, Ruiqiang; Li, Chang; Kang, Lin; Voskinarian-Berse, Vanessa; Zhang, Xiaokui; Streatfield, Stephen; Hambor, John; Abbot, Stewart

    2013-01-01

    Clinically available red blood cells (RBCs) for transfusions are at high demand, but in vitro generation of RBCs from hematopoietic stem cells requires significant quantities of growth factors. Here, we describe the production of four human growth factors: erythropoietin (EPO), stem cell factor (SCF), interleukin 3 (IL-3), and insulin-like growth factor-1 (IGF-1), either as non-fused proteins or as fusions with a carrier molecule (lichenase), in plants, using a Tobacco mosaic virus vector-based transient expression system. All growth factors were purified and their identity was confirmed by western blotting and peptide mapping. The potency of these plant-produced cytokines was assessed using TF1 cell (responsive to EPO, IL-3 and SCF) or MCF-7 cell (responsive to IGF-1) proliferation assays. The biological activity estimated here for the cytokines produced in plants was slightly lower or within the range cited in commercial sources and published literature. By comparing EC50 values of plant-produced cytokines with standards, we have demonstrated that all four plant-produced growth factors stimulated the expansion of umbilical cord blood-derived CD34+ cells and their differentiation toward erythropoietic precursors with the same potency as commercially available growth factors. To the best of our knowledge, this is the first report on the generation of all key bioactive cytokines required for the erythroid development in a cost-effective manner using a plant-based expression system. PMID:23517237

  11. Targeting cancer stem cell plasticity through modulation of epidermal growth factor and insulin-like growth factor receptor signaling in head and neck squamous cell cancer.

    PubMed

    Leong, Hui Sun; Chong, Fui Teen; Sew, Pui Hoon; Lau, Dawn P; Wong, Bernice H; Teh, Bin-Tean; Tan, Daniel S W; Iyer, N Gopalakrishna

    2014-09-01

    Emerging data suggest that cancer stem cells (CSCs) exist in equilibrium with differentiated cells and that stochastic transitions between these states can account for tumor heterogeneity and drug resistance. The aim of this study was to establish an in vitro system that recapitulates stem cell plasticity in head and neck squamous cell cancers (HNSCCs) and identify the factors that play a role in the maintenance and repopulation of CSCs. Tumor spheres were established using patient-derived cell lines via anchorage-independent cell culture techniques. These tumor spheres were found to have higher aldehyde dehydrogenase (ALD) cell fractions and increased expression of Kruppel-like factor 4, SRY (sex determining region Y)-box 2, and Nanog and were resistant to γ-radiation, 5-fluorouracil, cisplatin, and etoposide treatment compared with monolayer culture cells. Monolayer cultures were subject to single cell cloning to generate clones with high and low ALD fractions. ALDHigh clones showed higher expression of stem cell and epithelial-mesenchymal transition markers compared with ALDLow clones. ALD fractions, representing stem cell fractions, fluctuated with serial passaging, equilibrating at a level specific to each cell line, and could be augmented by the addition of epidermal growth factor (EGF) and/or insulin. ALDHigh clones showed increased EGF receptor (EGFR) and insulin-like growth factor-1 receptor (IGF-1R) phosphorylation, with increased activation of downstream pathways compared with ALDLow clones. Importantly, blocking these pathways using specific inhibitors against EGFR and IGF-1R reduced stem cell fractions drastically. Taken together, these results show that HNSCC CSCs exhibit plasticity, with the maintenance of the stem cell fraction dependent on the EGFR and IGF-1R pathways and potentially amenable to targeted therapeutics. ©AlphaMed Press.

  12. Gene therapy with growth factors for periodontal tissue engineering–A review

    PubMed Central

    Gupta, Shipra; Mahendra, Aneet

    2012-01-01

    The treatment of oral and periodontal diseases and associated anomalies accounts for a significant proportion of the healthcare burden, with the manifestations of these conditions being functionally and psychologically debilitating. A challenge faced by periodontal therapy is the predictable regeneration of periodontal tissues lost as a consequence of disease. Growth factors are critical to the development, maturation, maintenance and repair of oral tissues as they establish an extra-cellular environment that is conducive to cell and tissue growth. Tissue engineering principles aim to exploit these properties in the development of biomimetic materials that can provide an appropriate microenvironment for tissue development. The aim of this paper is to review emerging periodontal therapies in the areas of materials science, growth factor biology and cell/gene therapy. Various such materials have been formulated into devices that can be used as vehicles for delivery of cells, growth factors and DNA. Different mechanisms of drug delivery are addressed in the context of novel approaches to reconstruct and engineer oral and tooth supporting structure. Key words: Periodontal disease, gene therapy, regeneration, tissue repair, growth factors, tissue engineering. PMID:22143705

  13. A transcription factor links growth rate and metabolism in the hypersaline adapted archaeon Halobacterium salinarum.

    PubMed

    Todor, Horia; Dulmage, Keely; Gillum, Nicholas; Bain, James R; Muehlbauer, Michael J; Schmid, Amy K

    2014-09-01

    Co-ordinating metabolism and growth is a key challenge for all organisms. Despite fluctuating environments, cells must produce the same metabolic outputs to thrive. The mechanisms underlying this 'growth homeostasis' are known in bacteria and eukaryotes, but remain unexplored in archaea. In the model archaeon Halobacterium salinarum, the transcription factor TrmB regulates enzyme-coding genes in diverse metabolic pathways in response to glucose. However, H. salinarum is thought not to catabolize glucose. To resolve this discrepancy, we demonstrate that TrmB regulates the gluconeogenic production of sugars incorporated into the cell surface S-layer glycoprotein. Additionally, we show that TrmB-DNA binding correlates with instantaneous growth rate, likely because S-layer glycosylation is proportional to growth. This suggests that TrmB transduces a growth rate signal to co-regulated metabolic pathways including amino acid, purine, and cobalamin biosynthesis. Remarkably, the topology and function of this growth homeostatic network appear conserved across domains despite extensive alterations in protein components. © 2014 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd.

  14. A novel mechanism of vascular endothelial growth factor, leptin and transforming growth factor-beta2 sequestration in a subpopulation of human ovarian follicle cells.

    PubMed

    Antczak, M; Van Blerkom, J; Clark, A

    1997-10-01

    This study describes the occurrence of a highly specialized subpopulation of granulosa and cumulus oophorus cells that accumulate and sequester specific growth factors by a novel mechanism. These cells are characterized by multiple balloon-like processes tethered to the cell by means of a slender stalk of plasma membrane. Time-lapse analyses demonstrate that these tethered structures (TS) form in minutes and frequently detach from the cell with the bulbous portion remaining motile on the cell surface. Serial section reconstruction of transmission electron microscopic images shows a specific and stable intracellular organization in which an apparent secretory compartment composed of densely packed vacuoles, vesicles, and cisternae is separated by a thick filamentous network from a nuclear compartment containing mitochondria, polyribosomes, lipid inclusions, and rough-surfaced endoplasmic reticulum. Immunofluorescent analysis performed during the formation of these structures showed a progressive accumulation of vascular endothelial growth factor, leptin, and transforming growth factor-beta2 in the bulbous region. TS were identified in newly aspirated masses of granulosa and cumulus oophorus, and their production persists for months in culture. Observations of TS-forming cells made over several days of culture indicates that their production is episodic and factor release from these cells may be pulsatile. The findings suggest that a novel method of growth factor storage and release by an apparent apocrine-like mechanism occurs in the human ovarian follicle. The results are discussed with respect to possible roles in pre- and post-ovulatory follicular development.

  15. Teleost growth factor independence (gfi) genes differentially regulate successive waves of hematopoiesis.

    PubMed

    Cooney, Jeffrey D; Hildick-Smith, Gordon J; Shafizadeh, Ebrahim; McBride, Paul F; Carroll, Kelli J; Anderson, Heidi; Shaw, George C; Tamplin, Owen J; Branco, Diana S; Dalton, Arthur J; Shah, Dhvanit I; Wong, Clara; Gallagher, Patrick G; Zon, Leonard I; North, Trista E; Paw, Barry H

    2013-01-15

    Growth Factor Independence (Gfi) transcription factors play essential roles in hematopoiesis, differentially activating and repressing transcriptional programs required for hematopoietic stem/progenitor cell (HSPC) development and lineage specification. In mammals, Gfi1a regulates hematopoietic stem cells (HSC), myeloid and lymphoid populations, while its paralog, Gfi1b, regulates HSC, megakaryocyte and erythroid development. In zebrafish, gfi1aa is essential for primitive hematopoiesis; however, little is known about the role of gfi1aa in definitive hematopoiesis or about additional gfi factors in zebrafish. Here, we report the isolation and characterization of an additional hematopoietic gfi factor, gfi1b. We show that gfi1aa and gfi1b are expressed in the primitive and definitive sites of hematopoiesis in zebrafish. Our functional analyses demonstrate that gfi1aa and gfi1b have distinct roles in regulating primitive and definitive hematopoietic progenitors, respectively. Loss of gfi1aa silences markers of early primitive progenitors, scl and gata1. Conversely, loss of gfi1b silences runx-1, c-myb, ikaros and cd41, indicating that gfi1b is required for definitive hematopoiesis. We determine the epistatic relationships between the gfi factors and key hematopoietic transcription factors, demonstrating that gfi1aa and gfi1b join lmo2, scl, runx-1 and c-myb as critical regulators of teleost HSPC. Our studies establish a comparative paradigm for the regulation of hematopoietic lineages by gfi transcription factors. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Dynamic factor analysis of long-term growth trends of the intertidal seagrass Thalassia hemprichii in southern Taiwan

    NASA Astrophysics Data System (ADS)

    Kuo, Yi-Ming; Lin, Hsing-Juh

    2010-01-01

    We examined environmental factors which are most responsible for the 8-year temporal dynamics of the intertidal seagrass Thalassia hemprichii in southern Taiwan. A dynamic factor analysis (DFA), a dimension-reduction technique, was applied to identify common trends in a multivariate time series and the relationships between this series and interacting environmental variables. The results of dynamic factor models (DFMs) showed that the leaf growth rate of the seagrass was mainly influenced by salinity (Sal), tidal range (TR), turbidity ( K), and a common trend representing an unexplained variability in the observed time series. Sal was the primary variable that explained the temporal dynamics of the leaf growth rate compared to TR and K. K and TR had larger influences on the leaf growth rate in low- than in high-elevation beds. In addition to K, TR, and Sal, UV-B radiation (UV-B), sediment depth (SD), and a common trend accounted for long-term temporal variations of the above-ground biomass. Thus, K, TR, Sal, UV-B, and SD are the predominant environmental variables that described temporal growth variations of the intertidal seagrass T. hemprichii in southern Taiwan. In addition to environmental variables, human activities may be contributing to negative impacts on the seagrass beds; this human interference may have been responsible for the unexplained common trend in the DFMs. Due to successfully applying the DFA to analyze complicated ecological and environmental data in this study, important environmental variables and impacts of human activities along the coast should be taken into account when managing a coastal environment for the conservation of intertidal seagrass beds.

  17. FGF19 functions as autocrine growth factor for hepatoblastoma

    PubMed Central

    Elzi, David J.; Song, Meihua; Blackman, Barron; Weintraub, Susan T.; López-Terrada, Dolores; Chen, Yidong; Tomlinson, Gail E.; Shiio, Yuzuru

    2016-01-01

    Hepatoblastoma is the most common liver cancer in children, accounting for over 65% of all childhood liver malignancies. Hepatoblastoma is distinct from adult liver cancer in that it is not associated with hepatitis virus infection, cirrhosis, or other underlying liver pathology. The paucity of appropriate cell and animal models has been hampering the mechanistic understanding of hepatoblastoma pathogenesis. Consequently, there is no molecularly targeted therapy for hepatoblastoma. To gain insight into cytokine signaling in hepatoblastoma, we employed mass spectrometry to analyze the proteins secreted from Hep293TT hepatoblastoma cell line we established and identified the specific secretion of fibroblast growth factor 19 (FGF19), a growth factor for liver cells. We determined that silencing FGF19 by shRNAs or neutralizing secreted FGF19 by anti-FGF19 antibody inhibits the proliferation of hepatoblastoma cells. Furthermore, blocking FGF19 signaling by an FGF receptor kinase inhibitor suppressed hepatoblastoma growth. RNA expression analysis in hepatoblastoma tumors revealed that the high expression of FGF19 signaling pathway components as well as the low expression of FGF19 signaling repression targets correlates with the aggressiveness of the tumors. These results suggest the role of FGF19 as autocrine growth factor for hepatoblastoma. PMID:27382436

  18. Design and characteristics of cytotoxic fibroblast growth factor 1 conjugate for fibroblast growth factor receptor-targeted cancer therapy.

    PubMed

    Szlachcic, Anna; Zakrzewska, Malgorzata; Lobocki, Michal; Jakimowicz, Piotr; Otlewski, Jacek

    2016-01-01

    Fibroblast growth factor receptors (FGFRs) are attractive candidate cancer therapy targets as they are overexpressed in multiple types of tumors, such as breast, prostate, bladder, and lung cancer. In this study, a natural ligand of FGFR, an engineered variant of fibroblast growth factor 1 (FGF1V), was conjugated to a potent cytotoxic drug, monomethyl auristatin E (MMAE), and used as a targeting agent for cancer cells overexpressing FGFRs, similar to antibodies in antibody-drug conjugates. The FGF1V-valine-citrulline-MMAE conjugate showed a favorable stability profile, bound FGFRs on the cell surface specifically, and efficiently released the drug (MMAE) upon cleavage by the lysosomal protease cathepsin B. Importantly, the conjugate showed a prominent cytotoxic effect toward cell lines expressing FGFR. FGF1V-vcMMAE was highly cytotoxic at concentrations even an order of magnitude lower than those found for free MMAE. This effect was FGFR-specific as cells lacking FGFR did not show any increased mortality.

  19. Design and characteristics of cytotoxic fibroblast growth factor 1 conjugate for fibroblast growth factor receptor-targeted cancer therapy

    PubMed Central

    Szlachcic, Anna; Zakrzewska, Malgorzata; Lobocki, Michal; Jakimowicz, Piotr; Otlewski, Jacek

    2016-01-01

    Fibroblast growth factor receptors (FGFRs) are attractive candidate cancer therapy targets as they are overexpressed in multiple types of tumors, such as breast, prostate, bladder, and lung cancer. In this study, a natural ligand of FGFR, an engineered variant of fibroblast growth factor 1 (FGF1V), was conjugated to a potent cytotoxic drug, monomethyl auristatin E (MMAE), and used as a targeting agent for cancer cells overexpressing FGFRs, similar to antibodies in antibody–drug conjugates. The FGF1V–valine–citrulline–MMAE conjugate showed a favorable stability profile, bound FGFRs on the cell surface specifically, and efficiently released the drug (MMAE) upon cleavage by the lysosomal protease cathepsin B. Importantly, the conjugate showed a prominent cytotoxic effect toward cell lines expressing FGFR. FGF1V–vcMMAE was highly cytotoxic at concentrations even an order of magnitude lower than those found for free MMAE. This effect was FGFR-specific as cells lacking FGFR did not show any increased mortality. PMID:27563235

  20. Targeting placental growth factor/neuropilin 1 pathway inhibits growth and spread of medulloblastoma

    PubMed Central

    Snuderl, Matija; Batista, Ana; Kirkpatrick, Nathaniel D.; de Almodovar, Carmen Ruiz; Riedemann, Lars; Walsh, Elisa C.; Anolik, Rachel; Huang, Yuhui; Martin, John D.; Kamoun, Walid; Knevels, Ellen; Schmidt, Thomas; Farrar, Christian T.; Vakoc, Benjamin J.; Mohan, Nishant; Chung, Euiheon; Roberge, Sylvie; Peterson, Teresa; Bais, Carlos; Zhelyazkova, Boryana H.; Yip, Stephen; Hasselblatt, Martin; Rossig, Claudia; Niemeyer, Elisabeth; Ferrara, Napoleone; Klagsbrun, Michael; Duda, Dan G.; Fukumura, Dai; Xu, Lei; Carmeliet, Peter; Jain, Rakesh K.

    2013-01-01

    SUMMARY Medulloblastoma is the most common pediatric malignant brain tumor. Although current therapies improve survival, these regimens are highly toxic and associated with significant morbidity. Here, we report that placental growth factor (PlGF) is expressed in the majority of medulloblastomas independent of their subtype. Moreover, high expression of PlGF receptor neuropilin 1 (Nrp1) correlates with poor overall survival in patients. We demonstrate that PlGF and Nrp1 are required for the growth and spread of medulloblastoma: PlGF/Nrp1 blockade results in direct antitumor effects in vivo, resulting in medulloblastoma regression, decreased metastases, and increased mouse survival. We reveal that PlGF is produced in the cerebellar stroma via tumor-derived Sonic hedgehog (Shh) and show that PlGF acts through Nrp1—and not vascular endothelial growth factor receptor 1 (VEGFR1)—to promote tumor cell survival. This critical tumor-stroma interaction—mediated by Shh, PlGF, and Nrp1 across medulloblastoma subtypes—supports the development of therapies targeting PlGF/Nrp1 pathway. PMID:23452854

  1. Origin of platelet-derived growth factor in megakaryocytes in guinea pigs.

    PubMed Central

    Chernoff, A; Levine, R F; Goodman, D S

    1980-01-01

    Growth factor activity, as determined by the stimulation of [3H]thymidine incorporation into the DNA of quiescent 3T3 cells in culture, was found in lysates of guinea pig platelets and megakaryocytes. Quantitative dilution studies demonstrated that, of the cells present in the guinea pig bone marrow, only the megakaryocyte possessed quantitatively significant growth factor activity. The amount of activity present in one megakaryocyte was equivalent to that present in 1,000-5,000 platelets, a value approximately comparable to the number of platelets shed from a single megakaryocyte. It is suggested that guinea pig platelet-derived growth factor has its origin in the megakaryocyte. PMID:7358851

  2. Role of Fibroblast Growth Factor Binding Protein-1 in Mammary Development and Tumorigenesis

    DTIC Science & Technology

    2008-10-01

    AD_________________ AWARD NUMBER: W81XWH-06-1-0763 TITLE: Role of Fibroblast Growth Factor ...Role of Fibroblast Growth Factor Binding Protein-1 in Mammary Development and Tumorigenesis 5b. GRANT NUMBER W81XWH-06-1-0763 5c. PROGRAM...Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Fibroblast growth factors (FGFs) are vital modulators of development as well as

  3. On the dimensionality of the stress-related growth scale: one, three, or seven factors?

    PubMed

    Roesch, Scott C; Rowley, Anthony A; Vaughn, Allison A

    2004-06-01

    We examined the factorial validity and dimensionality of the Stress-Related Growth Scale (SRGS; Park, Cohen, & Murch, 1996) using a large multiethnic sample (n = 1,070). Exploratory and confirmatory factor analyses suggested that a multidimensional representation of the SRGS fit better than a unidimensional representation. Specifically, we cross-validated both a 3-factor model and a 7-factor model using confirmatory factor analysis and were shown to be invariant across gender and ethnic groups. The 3-factor model was represented by global dimensions of growth that included rational/mature thinking, affective/emotional growth, and religious/spiritual growth. We replicated the 7-factor model of Armeli, Gunthert, and Cohen (2001) and it represented more specific components of growth such as Self-Understanding and Treatment of Others. However, some factors of the 7-factor model had questionable internal consistency and were strongly intercorrelated, suggesting redundancy. The findings support the notion that the factor structure of both the original 1-factor and revised 7-factor models are unstable and that the 3-factor model developed in this research has more reliable psychometric properties and structure.

  4. Heritability of circulating growth factors involved in the angiogenesis in healthy human population.

    PubMed

    Pantsulaia, I; Trofimov, S; Kobyliansky, E; Livshits, G

    2004-09-21

    The present study examined the extent of genetic and environmental influences on the populational variation of circulating growth factors (VEGF, EGF) involved in angiogenesis in healthy and ethnically homogeneous Caucasian families. The plasma levels of each of the studied biochemical indices were determined by enzyme-linked immunoassay in 478 healthy individuals aged 18-75 years. Quantitative genetic analysis showed that the VEGF and EGF variation was appreciably attributable to genetic effects, with heritability estimates of 79.9% and 48.4%, respectively. Yet, common environmental factors, shared by members of the same household, also played a significant role (P < 0.01) and explained between 20.1% and 32.6% of the variation. The present study additionally examined the covariations between these molecules and either transforming growth factor-beta 1 (TGF-beta 1) or tissue inhibitors of matrix metalloproteinases 1 (TIMP-1), likewise relevant for angiogenesis. Bivariate analysis revealed significant phenotypic correlations (P < 0.002) between all pairs of variables, thus indicating the possible existence of common genetic and environmental factors. The analysis suggested that the pleiotropic genetic effects were consistently the primary (or even the sole) source of correlation between all pairs of studied molecules. The results of our study affirm the existence of specific and common genetic pathways that commonly determine the greater part of the circulating variation of these molecules.

  5. Growth factor delivery for oral and periodontal tissue engineering

    PubMed Central

    Kaigler, Darnell; Cirelli, Joni A; Giannobile, William V

    2008-01-01

    The treatment of oral and periodontal diseases and associated anomalies accounts for a significant proportion of the healthcare burden, with the manifestations of these conditions being functionally and psychologically debilitating. Growth factors are critical to the development, maturation, maintenance and repair of craniofacial tissues, as they establish an extracellular environment that is conducive to cell and tissue growth. Tissue-engineering principles aim to exploit these properties in the development of biomimetic materials that can provide an appropriate microenvironment for tissue development. These materials have been constructed into devices that can be used as vehicles for delivery of cells, growth factors and DNA. In this review, different mechanisms of drug delivery are addressed in the context of novel approaches to reconstruct and engineer oral- and tooth-supporting structures, namely the periodontium and alveolar bone. PMID:16948560

  6. Nanodiamond-based injectable hydrogel for sustained growth factor release: Preparation, characterization and in vitro analysis.

    PubMed

    Pacelli, Settimio; Acosta, Francisca; Chakravarti, Aparna R; Samanta, Saheli G; Whitlow, Jonathan; Modaresi, Saman; Ahmed, Rafeeq P H; Rajasingh, Johnson; Paul, Arghya

    2017-08-01

    Nanodiamonds (NDs) represent an emerging class of carbon nanomaterials that possess favorable physical and chemical properties to be used as multifunctional carriers for a variety of bioactive molecules. Here we report the synthesis and characterization of a new injectable ND-based nanocomposite hydrogel which facilitates a controlled release of therapeutic molecules for regenerative applications. In particular, we have formulated a thermosensitive hydrogel using gelatin, chitosan and NDs that provides a sustained release of exogenous human vascular endothelial growth factor (VEGF) for wound healing applications. Addition of NDs improved the mechanical properties of the injectable hydrogels without affecting its thermosensitive gelation properties. Biocompatibility of the generated hydrogel was verified by in vitro assessment of apoptotic gene expressions and anti-inflammatory interleukin productions. NDs were complexed with VEGF and the inclusion of this complex in the hydrogel network enabled the sustained release of the angiogenic growth factor. These results suggest for the first time that NDs can be used to formulate a biocompatible, thermosensitive and multifunctional hydrogel platform that can function both as a filling agent to modulate hydrogel properties, as well as a delivery platform for the controlled release of bioactive molecules and growth factors. One of the major drawbacks associated with the use of conventional hydrogels as carriers of growth factors is their inability to control the release kinetics of the loaded molecules. In fact, in most cases, a burst release is inevitable leading to diminished therapeutic effects and unsuccessful therapies. As a potential solution to this issue, we hereby propose a strategy of incorporating ND complexes within an injectable hydrogel matrix. The functional groups on the surface of the NDs can establish interactions with the model growth factor VEGF and promote a prolonged release from the polymer network

  7. Role of growth differentiation factor 11 in development, physiology and disease

    PubMed Central

    Zhang, Yonghui; Wei, Yong; Liu, Dan; Liu, Feng; Li, Xiaoshan; Pan, Lianhong; Pang, Yi; Chen, Dilong

    2017-01-01

    Growth differentiation factor (GDF11) is a member of TGF-β/BMP superfamily that activates Smad and non-Smad signaling pathways and regulates expression of its target nuclear genes. Since its discovery in 1999, studies have shown the involvement of GDF11 in normal physiological processes, such as embryonic development and erythropoiesis, as well as in the pathophysiology of aging, cardiovascular disease, diabetes mellitus, and cancer. In addition, there are contradictory reports regarding the role of GDF11 in aging, cardiovascular disease, diabetes mellitus, osteogenesis, skeletal muscle development, and neurogenesis. In this review, we describe the GDF11 signaling pathway and its potential role in development, physiology and disease. PMID:29113418

  8. Immobilization and Application of Electrospun Nanofiber Scaffold-based Growth Factor in Bone Tissue Engineering.

    PubMed

    Chen, Guobao; Lv, Yonggang

    2015-01-01

    Electrospun nanofibers have been extensively used in growth factor delivery and regenerative medicine due to many advantages including large surface area to volume ratio, high porosity, excellent loading capacity, ease of access and cost effectiveness. Their relatively large surface area is helpful for cell adhesion and growth factor loading, while storage and release of growth factor are essential to guide cellular behaviors and tissue formation and organization. In bone tissue engineering, growth factors are expected to transmit signals that stimulate cellular proliferation, migration, differentiation, metabolism, apoptosis and extracellular matrix (ECM) deposition. Bolus administration is not always an effective method for the delivery of growth factors because of their rapid diffusion from the target site and quick deactivation. Therefore, the integration of controlled release strategy within electrospun nanofibers can provide protection for growth factors against in vivo degradation, and can manipulate desired signal at an effective level with extended duration in local microenvironment to support tissue regeneration and repair which normally takes a much longer time. In this review, we provide an overview of growth factor delivery using biomimetic electrospun nanofiber scaffolds in bone tissue engineering. It begins with a brief introduction of different kinds of polymers that were used in electrospinning and their applications in bone tissue engineering. The review further focuses on the nanofiber-based growth factor delivery and summarizes the strategies of growth factors loading on the nanofiber scaffolds for bone tissue engineering applications. The perspectives on future challenges in this area are also pointed out.

  9. Characterization of the expression and clinical features of epidermal growth factor receptor and vascular endothelial growth factor receptor-2 in esophageal carcinoma

    PubMed Central

    NIYAZ, MADINIYAT; ANWER, JURAT; LIU, HUI; ZHANG, LIWEI; SHAYHEDIN, ILYAR; AWUT, IDIRIS

    2015-01-01

    The present study aimed to understand the expression characteristics of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor-2 (VEGFR-2) in individuals of Uygur, Han and Kazak ethnicity with esophageal carcinoma in Xinjiang (China) and their interrelation analysis, and to investigate the expression differences in these genes between esophageal carcinoma and pericarcinoma tissue samples, and between the three ethnic groups. The expression levels of EGFR and VEGFR-2 from 119 pairs of esophageal carcinoma tissue and corresponding pericarcinoma tissue from Uygur, Han and Kazak patients with esophageal carcinoma were detected by immunohistochemistry following surgical resection, and an additional five carcinoma in situ specimens were also tested. The relative expression was analyzed among the ethnic groups and clinicopathological parameters. The positive rate of EGFR in esophageal carcinoma tissue from patients of Uygur, Han and Kazak heritage was 70.73, 68.42 and 67.5%, respectively. For VEGFR-2 the positive rate was 73.17, 68.42 and 67.5%, respectively. No significant difference was detected in their expression between the three ethnic groups (P>0.05); however, EGFR and VEGFR-2 overexpression were correlated with lymph node metastasis (P<0.05). VEGF expression was also correlated with the expression of VEGFR-2 in esophageal carcinoma tissues. EGFR was positive in carcinoma in situ samples, while VEGFR-2 was negative. The overexpression of EGFR is therefore an early event and may have a significant role in the progression of esophageal carcinoma pathogenesis. EGFR overexpression may correlate with the expression of VEGFR-2 in esophageal cancer. These results may aid the early diagnosis of esophageal cancer, and the development of individual target treatment in the future. PMID:26788193

  10. UV-B Inhibits Leaf Growth through Changes in Growth Regulating Factors and Gibberellin Levels1[OPEN

    PubMed Central

    Fina, Julieta; AbdElgawad, Hamada; Prinsen, Els

    2017-01-01

    Ultraviolet-B (UV-B) radiation affects leaf growth in a wide range of species. In this work, we demonstrate that UV-B levels present in solar radiation inhibit maize (Zea mays) leaf growth without causing any other visible stress symptoms, including the accumulation of DNA damage. We conducted kinematic analyses of cell division and expansion to understand the impact of UV-B radiation on these cellular processes. Our results demonstrate that the decrease in leaf growth in UV-B-irradiated leaves is a consequence of a reduction in cell production and a shortened growth zone (GZ). To determine the molecular pathways involved in UV-B inhibition of leaf growth, we performed RNA sequencing on isolated GZ tissues of control and UV-B-exposed plants. Our results show a link between the observed leaf growth inhibition and the expression of specific cell cycle and developmental genes, including growth-regulating factors (GRFs) and transcripts for proteins participating in different hormone pathways. Interestingly, the decrease in the GZ size correlates with a decrease in the concentration of GA19, the immediate precursor of the active gibberellin, GA1, by UV-B in this zone, which is regulated, at least in part, by the expression of GRF1 and possibly other transcription factors of the GRF family. PMID:28400494

  11. Platelet-rich plasma stimulated by pulse electric fields: Platelet activation, procoagulant markers, growth factor release and cell proliferation.

    PubMed

    Frelinger, A L; Torres, A S; Caiafa, A; Morton, C A; Berny-Lang, M A; Gerrits, A J; Carmichael, S L; Neculaes, V B; Michelson, A D

    2016-01-01

    Therapeutic use of activated platelet-rich plasma (PRP) has been explored for wound healing, hemostasis and antimicrobial wound applications. Pulse electric field (PEF) stimulation may provide more consistent platelet activation and avoid complications associated with the addition of bovine thrombin, the current state of the art ex vivo activator of therapeutic PRP. The aim of this study was to compare the ability of PEF, bovine thrombin and thrombin receptor activating peptide (TRAP) to activate human PRP, release growth factors and induce cell proliferation in vitro. Human PRP was prepared in the Harvest SmartPreP2 System and treated with vehicle, PEF, bovine thrombin, TRAP or Triton X-100. Platelet activation and procoagulant markers and microparticle generation were measured by flow cytometry. Released growth factors were measured by ELISA. The releasates were tested for their ability to stimulate proliferation of human epithelial cells in culture. PEF produced more platelet-derived microparticles, P-selectin-positive particles and procoagulant annexin V-positive particles than bovine thrombin or TRAP. These differences were associated with higher levels of released epidermal growth factor after PEF than after bovine thrombin or TRAP but similar levels of platelet-derived, vascular-endothelial, and basic fibroblast growth factors, and platelet factor 4. Supernatant from PEF-treated platelets significantly increased cell proliferation compared to plasma. In conclusion, PEF treatment of fresh PRP results in generation of microparticles, exposure of prothrombotic platelet surfaces, differential release of growth factors compared to bovine thrombin and TRAP and significant cell proliferation. These results, together with PEF's inherent advantages, suggest that PEF may be a superior alternative to bovine thrombin activation of PRP for therapeutic applications.

  12. [Fibroblast growth factors and their effects in pancreas organogenesis].

    PubMed

    Gnatenko, D A; Kopantzev, E P; Sverdlov, E D

    2017-05-01

    Fibroblast growth factors (FGF) - growth factors that regulate many important biological processes, including proliferation and differentiation of embryonic cells during organogenesis. In this review, we will summarize current information about the involvement of FGFs in the pancreas organogenesis. Pancreas organogenesis is a complex process, which involves constant signaling from mesenchymal tissue. This orchestrates the activation of various regulator genes at specific stages, determining the specification of progenitor cells. Alterations in FGF/FGFR signaling pathway during this process lead to incorrect activation of the master genes, which leads to different pathologies during pancreas development. Understanding the full picture about role of FGF factors in pancreas development will make it possible to more accurately understand their role in other pathologies of this organ, including carcinogenesis.

  13. Quantification of various growth factors in different demineralized bone matrix preparations.

    PubMed

    Wildemann, B; Kadow-Romacker, A; Haas, N P; Schmidmaier, G

    2007-05-01

    Besides autografts, allografts, and synthetic materials, demineralized bone matrix (DBM) is used for bone defect filling and treatment of non-unions. Different DBM formulations are introduced in clinic since years. However, little is known about the presents and quantities of growth factors in DBM. Aim of the present study was the quantification of eight growth factors important for bone healing in three different "off the shelf" DBM formulations, which are already in human use: DBX putty, Grafton DBM putty, and AlloMatrix putty. All three DBM formulations are produced from human donor tissue but they differ in the substitutes added. From each of the three products 10 different lots were analyzed. Protein was extracted from the samples with Guanidine HCL/EDTA method and human ELISA kits were used for growth factor quantification. Differences between the three different products were seen in total protein contend and the absolute growth factor values but also a large variability between the different lots was found. The order of the growth factors, however, is almost comparable between the materials. In the three investigated materials FGF basic and BMP-4 were not detectable in any analyzed sample. BMP-2 revealed the highest concentration extractable from the samples with approximately 3.6 microg/g tissue without a significant difference between the three DBM formulations. In DBX putty significantly more TGF-beta1 and FGFa were measurable compared to the two other DBMs. IGF-I revealed the significantly highest value in the AlloMatrix and PDGF in Grafton. No differences were accessed for VEGF. Due to the differences in the growth factor concentration between the individual samples, independently from the product formulation, further analyzes are required to optimize the clinical outcome of the used demineralized bone matrix. Copyright 2006 Wiley Periodicals, Inc.

  14. Rearing Mozambique tilapia in tidally-changing salinities: Effects on growth and the growth hormone/insulin-like growth factor I axis.

    PubMed

    Moorman, Benjamin P; Yamaguchi, Yoko; Lerner, Darren T; Grau, E Gordon; Seale, Andre P

    2016-08-01

    The growth hormone (GH)/insulin-like growth factor (IGF) axis plays a central role in the regulation of growth in teleosts and has been shown to be affected by acclimation salinity. This study was aimed at characterizing the effects of rearing tilapia, Oreochromis mossambicus, in a tidally-changing salinity on the GH/IGF axis and growth. Tilapia were raised in fresh water (FW), seawater (SW), or in a tidally-changing environment, in which salinity is switched between FW (TF) and SW (TS) every 6h, for 4months. Growth was measured over all time points recorded and fish reared in a tidally-changing environment grew significantly faster than other groups. The levels of circulating growth hormone (GH), insulin-like growth factor I (IGF-I), pituitary GH mRNA, gene expression of IGF-I, IGF-II, and growth hormone receptor 2 (GHR) in the muscle and liver were also determined. Plasma IGF-I was higher in FW and TS than in SW and TF tilapia. Pituitary GH mRNA was higher in TF and TS than in FW and SW tilapia. Gene expression of IGF-I in the liver and of GHR in both the muscle and liver changed between TF and TS fish. Fish growth was positively correlated with GH mRNA expression in the pituitary, and GHR mRNA expression in muscle and liver tissues. Our study indicates that rearing fish under tidally-changing salinities elicits a distinct pattern of endocrine regulation from that observed in fish reared in steady-state conditions, and may provide a new approach to increase tilapia growth rate and study the regulation of growth in euryhaline fish. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Immunohistochemical profile of cytokines and growth factors expressed in vestibular schwannoma and in normal vestibular nerve tissue.

    PubMed

    Taurone, Samanta; Bianchi, Enrica; Attanasio, Giuseppe; Di Gioia, Cira; Ierinó, Rocco; Carubbi, Cecilia; Galli, Daniela; Pastore, Francesco Saverio; Giangaspero, Felice; Filipo, Roberto; Zanza, Christian; Artico, Marco

    2015-07-01

    Vestibular schwannomas, also known as acoustic neuromas, are benign tumors, which originate from myelin-forming Schwann cells. They develop in the vestibular branch of the eighth cranial nerve in the internal auditory canal or cerebellopontine angle. The clinical progression of the condition involves slow and progressive growth, eventually resulting in brainstem compression. The objective of the present study was to investigate the expression level and the localization of the pro-inflammatory cytokines, transforming growth factor-β1 (TGF-β1) interleukin (IL)-1β, IL-6 and tumor necrosis factor-α (TNF-α), as well as the adhesion molecules, intracellular adhesion molecule-1 and vascular endothelial growth factor (VEGF), in order to determine whether these factors are involved in the transformation and development of human vestibular schwannoma. The present study investigated whether changes in inflammation are involved in tumor growth and if so, the mechanisms underlying this process. The results of the current study demonstrated that pro-inflammatory cytokines, including TGF-β1, IL-1β and IL-6 exhibited increased expression in human vestibular schwannoma tissue compared with normal vestibular nerve samples. TNF-α was weakly expressed in Schwann cells, confirming that a lower level of this cytokine is involved in the proliferation of Schwann cells. Neoplastic Schwann cells produce pro-inflammatory cytokines that may act in an autocrine manner, stimulating cellular proliferation. In addition, the increased expression of VEGF in vestibular schwannoma compared with that in normal vestibular nerve tissue, suggests that this factor may induce neoplastic growth via the promotion of angiogenesis. The present findings suggest that inflammation may promote angiogenesis and consequently contribute to tumor progression. In conclusion, the results of the present study indicated that VEGF and pro-inflammatory cytokines may be potential therapeutic targets in vestibular

  16. Bone morphogenetic protein-4 strongly potentiates growth factor-induced proliferation of mammary epithelial cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Montesano, Roberto; Sarkoezi, Rita; Schramek, Herbert

    2008-09-12

    Bone morphogenetic proteins (BMPs) are multifunctional cytokines that elicit pleiotropic effects on biological processes such as cell proliferation, cell differentiation and tissue morphogenesis. With respect to cell proliferation, BMPs can exert either mitogenic or anti-mitogenic activities, depending on the target cells and their context. Here, we report that in low-density cultures of immortalized mammary epithelial cells, BMP-4 did not stimulate cell proliferation by itself. However, when added in combination with suboptimal concentrations of fibroblast growth factor (FGF)-2, FGF-7, FGF-10, epidermal growth factor (EGF) or hepatocyte growth factor (HGF), BMP-4 potently enhanced growth factor-induced cell proliferation. These results reveal a hithertomore » unsuspected interplay between BMP-4 and growth factors in the regulation of mammary epithelial cell proliferation. We suggest that the ability of BMP-4 to potentiate the mitogenic activity of multiple growth factors may contribute to mammary gland ductal morphogenesis as well as to breast cancer progression.« less

  17. Extracellular Matrix-Inspired Growth Factor Delivery Systems for Skin Wound Healing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Briquez, Priscilla S.; Hubbell, Jeffrey A.; Martino, Mikaël M.

    2015-08-01

    Blood vessel growth plays a key role in regenerative medicine, both to restore blood supply to ischemic tissues and to ensure rapid vascularization of clinical-size tissue-engineered grafts. For example, vascular endothelial growth factor (VEGF) is the master regulator of physiological blood vessel growth and is one of the main molecular targets of therapeutic angiogenesis approaches. However, angiogenesis is a complex process and there is a need to develop rational therapeutic strategies based on a firm understanding of basic vascular biology principles, as evidenced by the disappointing results of initial clinical trials of angiogenic factor delivery. In particular, the spatial localizationmore » of angiogenic signals in the extracellular matrix (ECM) is crucial to ensure the proper assembly and maturation of new vascular structures. Here, we discuss the therapeutic implications of matrix interactions of angiogenic factors, with a special emphasis on VEGF, as well as provide an overview of current approaches, based on protein and biomaterial engineering that mimic the regulatory functions of ECM to optimize the signaling microenvironment of vascular growth factors.« less

  18. Phosphorylation of hepatocyte growth factor receptor and epidermal growth factor receptor of human hepatocytes can be maintained in a (3D) collagen sandwich culture system.

    PubMed

    Engl, Tobias; Boost, Kim A; Leckel, Kerstin; Beecken, Wolf-Dietrich; Jonas, Dietger; Oppermann, Elsie; Auth, Marcus K H; Schaudt, André; Bechstein, Wolf-Otto; Blaheta, Roman A

    2004-08-01

    In vitro culture models that employ human liver cells could be potent tools for predictive studies on drug toxicity and metabolism in the pharmaceutical industry. However, an adequate receptor responsiveness is necessary to allow intracellular signalling and metabolic activity. We tested the ability of three-dimensionally arranged human hepatocytes to respond to the growth factors hepatocyte growth factor (HGF) or epidermal growth factor (EGF). Isolated adult human hepatocytes were cultivated within a three-dimensional collagen gel (sandwich) or on a two-dimensional collagen matrix. Cells were treated with HGF or EGF and expression and phosphorylative activity of HGF receptors (HGFr, c-met) or EGF receptors (EGFr) were measured by flow cytometry and Western blot. Increasing HGFr and EGFr levels were detected in hepatocytes growing two-dimensionally. However, both receptors were not activated in presence of growth factors. In contrast, when hepatocytes were plated within a three-dimensional matrix, HGFr and EGFr levels remained constantly low. However, both receptors became strongly phosphorylated by soluble HGF or EGF. We conclude that cultivation of human hepatocytes in a three-dimensionally arranged in vitro system allows the maintenance of specific functional activities. The necessity of cell dimensionality for HGFr and EGFr function should be considered when an adequate in vitro system has to be introduced for drug testing.

  19. Antivascular Endothelial Growth Factor Bevacizumab for Radiation Optic Neuropathy: Secondary to Plaque Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Finger, Paul T., E-mail: pfinger@eyecancer.com; Chin, Kimberly J.

    2012-02-01

    Purpose: To evaluate the intravitreal antivascular endothelial growth factor, bevacizumab, for treatment of radiation optic neuropathy (RON). Methods and Materials: A prospective interventional clinical case series was performed of 14 patients with RON related to plaque radiotherapy for choroidal melanoma. The RON was characterized by optic disc edema, hemorrhages, microangiopathy, and neovascularization. The entry criteria included a subjective or objective loss of vision, coupled with findings of RON. The study subjects received a minimum of two initial injections of intravitreal bevacizumab (1.25 mg in 0.05 mL) every 6-8 weeks. The primary objectives included safety and tolerability. The secondary objectives includedmore » the efficacy as measured using the Early Treatment Diabetic Retinopathy Study chart for visual acuity, fundus photography, angiography, and optical coherence tomography/scanning laser ophthalmoscopy. Results: Reductions in optic disc hemorrhage and edema were noted in all patients. The visual acuity was stable or improved in 9 (64%) of the 14 patients. Of the 5 patients who had lost vision, 2 had relatively large posterior tumors, 1 had had the vision decrease because of intraocular hemorrhage, and 1 had developed optic atrophy. The fifth patient who lost vision was noncompliant. No treatment-related ocular or systemic side effects were observed. Conclusions: Intravitreal antivascular endothelial growth factor bevacizumab was tolerated and generally associated with improved vision, reduced papillary hemorrhage, and resolution of optic disc edema. Persistent optic disc neovascularization and fluorescein angiographic leakage were invariably noted. The results of the present study support additional evaluation of antivascular endothelial growth factor medications as treatment of RON.« less

  20. R7 Photoreceptor Axon Growth Is Temporally Controlled by the Transcription Factor Ttk69, Which Inhibits Growth in Part by Promoting Transforming Growth Factor-β/Activin Signaling

    PubMed Central

    Kniss, Jonathan S.; Holbrook, Scott

    2013-01-01

    Work on axon growth has classically focused on understanding how extrinsic cues control growth cone dynamics independent of the cell body. However, more recently, neuron-intrinsic transcription factors have been shown to influence both normal and regenerative axon growth, suggesting that understanding their mechanism of action is of clinical importance. We are studying axon targeting in the Drosophila visual system and here show that the BTB/POZ zinc-finger transcription factor Tramtrack69 (Ttk69) plays an instructive role in inhibiting the growth of R7 photoreceptor axon terminals. Although ttk69 mutant R7 axons project to the correct medullar target layer, M6, their terminals fail to remain retinotopically restricted and instead grow laterally within M6. This overgrowth is not caused by an inability to be repelled by neighboring R7 axons or by an inability to recognize and initiate synapse formation with postsynaptic targets. The overgrowth is progressive and occurs even if contact between ttk69 mutant R7 axons and their normal target layer is disrupted. Ttk69 is first expressed in wild-type R7s after their axons have reached the medulla; ttk69 mutant R7 axon terminal overgrowth begins shortly after this time point. We find that expressing Ttk69 prematurely in R7s collapses their growth cones and disrupts axon extension, indicating that Ttk69 plays an instructive role in this process. A TGF-β/Activin pathway was shown previously to inhibit R7 axon terminal growth. We find that Ttk69 is required for normal activation of this pathway but that Ttk69 likely also inhibits R7 axon growth by a TGF-β/Activin-independent mechanism. PMID:23345225

  1. Genetic polymorphisms and protein structures in growth hormone, growth hormone receptor, ghrelin, insulin-like growth factor 1 and leptin in Mehraban sheep.

    PubMed

    Bahrami, A; Behzadi, Sh; Miraei-Ashtiani, S R; Roh, S-G; Katoh, K

    2013-09-15

    The somatotropic axis, the control system for growth hormone (GH) secretion and its endogenous factors involved in the regulation of metabolism and energy partitioning, has promising potentials for producing economically valuable traits in farm animals. Here we investigated single nucleotide polymorphisms (SNPs) of the genes of factors involved in the somatotropic axis for growth hormone (GH1), growth hormone receptor (GHR), ghrelin (GHRL), insulin-like growth factor 1 (IGF-I) and leptin (LEP), using polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and DNA sequencing methods in 452 individual Mehraban sheep. A nonradioactive method to allow SSCP detection was used for genomic DNA and PCR amplification of six fragments: exons 4 and 5 of GH1; exon 10 of GH receptor (GHR); exon 1 of ghrelin (GHRL); exon 1 of insulin-like growth factor-I (IGF-I), and exon 3 of leptin (LEP). Polymorphisms were detected in five of the six PCR products. Two electrophoretic patterns were detected for GH1 exon 4. Five conformational patterns were detected for GH1 exon 5 and LEP exon 3, and three for IGF-I exon 1. Only GHR and GHRL were monomorphic. Changes in protein structures due to variable SNPs were also analyzed. The results suggest that Mehraban sheep, a major breed that is important for the animal industry in Middle East countries, has high genetic variability, opening interesting prospects for future selection programs and preservation strategies. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. The growth hormone–insulin-like growth factor-I axis in the diagnosis and treatment of growth disorders

    PubMed Central

    Blum, Werner F; Alherbish, Abdullah; Alsagheir, Afaf; El Awwa, Ahmed; Kaplan, Walid; Koledova, Ekaterina; Savage, Martin O

    2018-01-01

    The growth hormone (GH)–insulin-like growth factor (IGF)-I axis is a key endocrine mechanism regulating linear growth in children. While paediatricians have a good knowledge of GH secretion and assessment, understanding and use of measurements of the components of the IGF system are less current in clinical practice. The physiological function of this axis is to increase the anabolic cellular processes of protein synthesis and mitosis, and reduction of apoptosis, with each being regulated in the appropriate target tissue. Measurement of serum IGF-I and IGF-binding protein (IGFBP)-3 concentrations can complement assessment of GH status in the investigation of short stature and contribute to prediction of growth response during GH therapy. IGF-I monitoring during GH therapy also informs the clinician about adherence and provides a safety reference to avoid over-dosing during long-term management. PMID:29724795

  3. The growth hormone-insulin-like growth factor-I axis in the diagnosis and treatment of growth disorders.

    PubMed

    Blum, Werner; Alherbish, Abdullah; Alsagheir, Afaf; El Awwa, Ahmed; Kaplan, Walid; Koledova, Ekaterina; Savage, Martin O

    2018-05-03

    The growth hormone (GH)-insulin-like growth factor (IGF)-I axis is a key endocrine mechanism regulating linear growth in children. While paediatricians have a good knowledge of GH secretion and assessment, understanding and use of measurements of the components of the IGF system are less current in clinical practice. The physiological function of this axis is to increase the anabolic cellular processes of protein synthesis and mitosis, and reduction of apoptosis, with each being regulated in the appropriate target tissue. Measurement of serum IGF-I and IGFBP-3 concentrations can complement assessment of GH status in the investigation of short stature and contribute to prediction of growth response during GH therapy. IGF-I monitoring during GH therapy also informs the clinician about adherence and provides a safety reference to avoid over-dosing during long-term management.

  4. Tissular growth factors profile after teduglutide administration on an animal model of intestinal anastomosis.

    PubMed

    Costa, Beatriz Pinto; Gonçalves, Ana Cristina; Abrantes, Ana Margarida; Alves, Raquel; Matafome, Paulo; Seiça, Raquel; Sarmento-Ribeiro, Ana Bela; Botelho, Maria Filomena; Castro-Sousa, Francisco

    2018-01-16

    Teduglutide is an enterotrophic analogue of glucagon-like peptide-2, with an indirect and poorly understood mechanism of action, approved for the rehabilitation of short-bowel syndrome. This study aims to analyze the response of tissue growth factors to surgical injury and teduglutide administration on an animal model of intestinal anastomosis. Wistar rats (n = 59) were distributed into four groups: "ileal resection" or "laparotomy", each one subdivided into "postoperative teduglutide administration" or "no treatment"; and sacrificed at the third or the seventh day, with ileal sample harvesting. Gene expression of insulin-like growth factor 1 (Igf1), vascular endothelial growth factor a (Vegfa), transforming growth factor β1 (Tgfβ1), connective tissue growth factor (Ctgf), fibroblast growth factor 2 (Fgf2), fibroblast growth factor 7 (Fgf7), epidermal growth factor (Egf), heparin-binding epidermal-like growth factor (Hbegf), platelet-derived growth factor b (Pdgfb) and glucagon-like peptide 2 receptor (Glp2r)was studied by real-time polymerase chain reaction. Upregulation of Fgf7, Fgf2, Egf, Vegfaand Glp2rat the third day and of Pdgfat the seventh day was verified in the perianastomotic segment. Teduglutide administration was associated with higher fold-change of relative gene expression of Vegfa(3.6 ± 1.3 vs.1.9 ± 2.0, p = 0.0001), Hbegf(2.2 ± 2.3 vs. 1.1 ± 0.9, p = 0.001), Igf1(1.6 ± 7.6 vs. 0.9 ± 0.7, p = 0.002) and Ctgf(1.1 ± 2.1 vs. 0.6 ± 2.0, p = 0.013); and lower fold-change of Tgfβ1, Fgf7and Glp2r. Those results underscore the recognized role of Igf1and Hbegfas molecular mediators of the effects of teduglutide and suggest that other humoral factors, like Vegfand Ctgf, may also be relevant in the perioperative context. Induction of Vegfa, Igf1and Ctgfgene expressions might indicate a favorable influence of teduglutide on the intestinal anastomotic healing.

  5. Cell-extracellular matrix interactions can regulate the switch between growth and differentiation in rat hepatocytes: reciprocal expression of C/EBP alpha and immediate-early growth response transcription factors.

    PubMed Central

    Rana, B; Mischoulon, D; Xie, Y; Bucher, N L; Farmer, S R

    1994-01-01

    Previous investigations have shown that culture of freshly isolated hepatocytes under conventional conditions, i.e., on dried rat tail collagen in the presence of growth factors, facilitates cell growth but also causes an extensive down-regulation of most liver-specific functions. This dedifferentiation process can be prevented if the cells are cultured on a reconstituted basement membrane gel matrix derived from the Englebreth-Holm-Swarm mouse sarcoma tumor (EHS gel). To gain insight into the mechanisms regulating this response to extracellular matrix, we are analyzing the activities of two families of transcription factors, C/EBP and AP-1, which control the transcription of hepatic and growth-responsive genes, respectively. We demonstrate that isolation of hepatocytes from the normal quiescent rat liver by collagenase perfusion activates the immediate-early growth response program, as indicated by increased expression of c-jun, junB, c-fos, and c-myc mRNAs. Adhesion of these activated cells to dried rat tail collagen augments the elevated levels of these mRNAs for the initial 1 to 2 h postplating; junB and c-myc mRNA levels then drop steeply, with junB returning to normal quiescence and the c-myc level remaining slightly elevated during the 3-day culture period. Levels of c-jun mRNA and AP-1 DNA binding activity, however, remain elevated from the outset, while C/EBP alpha mRNA expression is down-regulated, resulting in a decrease in the steady-state levels of the 42- and 30-kDa C/EBP alpha polypeptides and C/EBP alpha DNA binding activity. In contrast, C/EBP beta mRNA production remains at near-normal hepatic levels for 5 to 8 days of culture, although its DNA binding activity decreases severalfold during this time. Adhesion of hepatocytes to the EHS gel for the same period of time dramatically alters this program: it arrests growth and inhibits AP-1 DNA binding activity and the expression of c-jun, junB, and c-myc mRNAs, but, in addition, it restores C/EBP alpha

  6. Effects of different growth factors and carriers on bone regeneration: a systematic review.

    PubMed

    Khojasteh, Arash; Behnia, Hossein; Naghdi, Navid; Esmaeelinejad, Mohammad; Alikhassy, Zahra; Stevens, Mark

    2013-12-01

    The application and subsequent investigations in the use of varied osteogenic growth factors in bone regeneration procedures have grown dramatically over the past several years. Owing to this rapid gain in popularity and documentation, a review was undertaken to evaluate the in vivo effects of growth factors on bone regeneration. Using related key words, electronic databases (Medline, Embase, and Cochrane) were searched for articles published from 1999 to April 2010 to find growth factor application in bone regeneration in human or animal models. A total of 63 articles were matched with the inclusion criteria of this study. Bone morphogenetic protein 2 (BMP-2) was the most studied growth factor. Carriers for the delivery, experimental sites, and methods of evaluation were different, and therefore articles did not come to a general agreement. Within the limitations of this review, BMP-2 may be an appropriate growth factor for osteogenesis. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Mesenchymal Stem Cells Suppress Chronic Rejection in Heterotopic Small Intestine Transplant Rat Models Via Inhibition of CD68, Transforming Growth Factor- β1, and Platelet-Derived Growth Factor Expression.

    PubMed

    Li, Fuxin; Cao, Jisen; Zhao, Zhicheng; Li, Chuan; Qi, Feng; Liu, Tong

    2017-04-01

    Mesenchymal stem cells are easy to obtain and expand, with characteristics of low immunogenicity and strong tissue repair capacity. In this study, our aim was to investigate the role of mesenchymal stem cells in chronic immune rejection of heterotopic small intestine transplant in rats. After successfully constructing a rat chronic immune rejection model of heterotopic small intestine transplant, we infused mesenchymal stem cells into the animal recipients. We observed mesenchymal stem cell location in the recipients, recipient survival, pathology changes, and the expression of CD68, transforming growth factor β1, and platelet-derived growth factor C in the donor intestine. Mesenchymal stem cells inhibited the lymphocyte proliferation caused by concanavalin A in vitro. After stem cells were infused into recipients, they were mainly located in the donor intestine, as well as in the spleen and thymus. Recovery after transplant and pathology changes of the donor intestine in rats with stem cell infusion were better than in the control group; however, we observed no differences in survival time, accompanied by downregulated expression of CD68, transforming growth factor β1, and platelet-derived growth factor C. Mesenchymal stem cells, to a certain extent, could inhibit the process of chronic rejection. The mechanisms may include the inhibited function of these cells on lymphocyte proliferation, reduced infiltration of macrophages, and reduced expression of transforming growth factor β1 and platelet-derived growth factor C.

  8. Insulin-like growth factors and insulin: at the crossroad between tumor development and longevity.

    PubMed

    Novosyadlyy, Ruslan; Leroith, Derek

    2012-06-01

    Numerous lines of evidence indicate that insulin-like growth factor signaling plays an important role in the regulation of life span and tumor development. In the present paper, the role of individual components of insulin-like growth factor signaling in aging and tumor development has been extensively analyzed. The molecular mechanisms underlying aging and tumor development are frequently overlapping. Although the link between reduced insulin-like growth factor signaling and suppressed tumor growth and development is well established, it remains unclear whether extended life span results from direct suppression of insulin-like growth factor signaling or this effect is caused by indirect mechanisms such as improved insulin sensitivity.

  9. Controllable mineral coatings on PCL scaffolds as carriers for growth factor release

    PubMed Central

    Suárez-González, Darilis; Barnhart, Kara; Migneco, Francesco; Flanagan, Colleen; Hollister, Scott J.; Murphy, William L.

    2011-01-01

    In this study, we have developed mineral coatings on polycaprolactone scaffolds to serve as templates for growth factor binding and release. Mineral coatings were formed using a biomimetic approach that consisted in the incubation of scaffolds in modified simulated body fluids (mSBF). To modulate the properties of the mineral coating, which we hypothesized would dictate growth factor release, we used carbonate (HCO3) concentration in mSBF of 4.2 mM, 25mM, and 100mM. Analysis of the mineral coatings formed using scanning electron microscopy indicated growth of a continuous layer of mineral with different morphologies. X-ray diffraction analysis showed peaks associated with hydroxyapatite, the major inorganic constituent of human bone tissue in coatings formed in all HCO3 concentrations. Mineral coatings with increased HCO3 substitution showed more rapid dissolution kinetics in an environment deficient in calcium and phosphate but showed re-precipitation in an environment with the aforementioned ions. The mineral coating provided an effective mechanism for growth factor binding and release. Peptide versions of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2) were bound with efficiencies up to 90% to mineral mineral-coated PCL scaffolds. We also demonstrated sustained release of all growth factors with release kinetics that were strongly dependent in the solubility of the mineral coating. PMID:22014948

  10. Congestive Heart Failure During Osimertinib Treatment for Epidermal Growth Factor Receptor (EGFR)-mutant Non-small Cell Lung Cancer (NSCLC).

    PubMed

    Watanabe, Hiromi; Ichihara, Eiki; Kano, Hirohisa; Ninomiya, Kiichiro; Tanimoto, Mitsune; Kiura, Katsuyuki

    2017-08-15

    We herein report a case of congestive heart failure which developed during osimertinib treatment. A 78-year-old woman presented with mild exertional dyspnea three weeks after starting osimertinib for the treatment of epidermal growth factor receptor (EGFR) T790M-positive non-small cell lung cancer. She was diagnosed with congestive heart failure caused by the osimertinib. In contrast to trastuzumab, a human epidermal growth factor receptor 2 (HER2) monoclonal antibody that often causes cardiac dysfunction, the causal relationship between osimertinib and cardiotoxicity has so far received little attention and thus remains unclear. However, it inhibits HER2 in addition to mutant EGFR, thereby potentially causing cardiotoxicity.

  11. Congestive Heart Failure During Osimertinib Treatment for Epidermal Growth Factor Receptor (EGFR)-mutant Non-small Cell Lung Cancer (NSCLC)

    PubMed Central

    Watanabe, Hiromi; Ichihara, Eiki; Kano, Hirohisa; Ninomiya, Kiichiro; Tanimoto, Mitsune; Kiura, Katsuyuki

    2017-01-01

    We herein report a case of congestive heart failure which developed during osimertinib treatment. A 78-year-old woman presented with mild exertional dyspnea three weeks after starting osimertinib for the treatment of epidermal growth factor receptor (EGFR) T790M-positive non-small cell lung cancer. She was diagnosed with congestive heart failure caused by the osimertinib. In contrast to trastuzumab, a human epidermal growth factor receptor 2 (HER2) monoclonal antibody that often causes cardiac dysfunction, the causal relationship between osimertinib and cardiotoxicity has so far received little attention and thus remains unclear. However, it inhibits HER2 in addition to mutant EGFR, thereby potentially causing cardiotoxicity. PMID:28781309

  12. L-ascorbic acid 2-phosphate and fibroblast growth factor-2 treatment maintains differentiation potential in bone marrow-derived mesenchymal stem cells through expression of hepatocyte growth factor.

    PubMed

    Bae, Sung Hae; Ryu, Hoon; Rhee, Ki-Jong; Oh, Ji-Eun; Baik, Soon Koo; Shim, Kwang Yong; Kong, Jee Hyun; Hyun, Shin Young; Pack, Hyun Sung; Im, Changjo; Shin, Ha Cheol; Kim, Yong Man; Kim, Hyun Soo; Eom, Young Woo; Lee, Jong In

    2015-04-01

    l-ascorbic acid 2-phosphate (Asc-2P) acts as an antioxidant and a stimulator of hepatocyte growth factor (HGF) production. Previously, we reported that depletion of growth factors such as fibroblast growth factor (FGF)-2, epidermal growth factor (EGF), FGF-4 and HGF during serial passage could induce autophagy, senescence and down-regulation of stemness (proliferation via FGF-2/-4 and differentiation via HGF). In this study, we investigated the proliferation and differentiation potential of BMSCs by FGF-2 and Asc-2P. Co-treatment with FGF-2 and Asc-2P induced optimal proliferation of BMSCs and increased the accumulation rate of BMSC numbers during a 2-month culture period. Moreover, differentiation potential was maintained by co-treatment with FGF-2 and Asc-2P via HGF expression. Adipogenic differentiation potential by FGF-2 and Asc-2P was dramatically suppressed by c-Met inhibitors (SU11274). These data suggest that co-treatment with FGF-2 and Asc-2P would be beneficial in obtaining BMSCs that possess "stemness" during long-term culture.

  13. Insulin-like growth factor-I and insulin-like growth factor binding protein-3 cotreatment versus insulin-like growth factor-I alone in two brothers with growth hormone insensitivity syndrome: effects on insulin sensitivity, body composition and linear growth.

    PubMed

    Ekström, Klas; Carlsson-Skwirut, Christine; Ritzén, E Martin; Bang, Peter

    2011-01-01

    Growth hormone insensitivity syndrome (GHIS) is caused by a defective growth hormone receptor (GHR) and is associated with insulin-like growth factor-I (IGF-I) deficiency, severely short stature and, from adolescence, fasting hyperglycemia and obesity. We studied the effects of treatment with IGF-I in either a 1:1 molar complex with IGFBP-3 (IGF-I/BP-3-Tx) or with IGF-I alone (IGF-I-Tx) on metabolism and linear growth. Two brothers, compound heterozygous for a GHR gene defect, were studied. After 8 months without treatment, we examined the short- and long-term effects of IGF-I/BP-3-Tx and, subsequently, IGF-I-Tx on 12-hour overnight levels of IGF-I, GH, insulin, IGFBP-1, insulin sensitivity by hyperinsulinemic euglycemic clamp, body composition by dual-energy X-ray absorptiometry and linear growth. Mean overnight levels of insulin decreased and IGFBP-1, a measure of hepatic insulin sensitivity, increased on both regimens, but was more pronounced on IGF-I-Tx. Insulin sensitivity by clamp showed no consistent changes. Lean body mass increased and abdominal fat mass decreased in both subjects on IGF-I-Tx. However, the changes were inconsistent during IGF-I/BP-3-Tx. Height velocity was low without treatment, increased slightly on IGF-I/BP-3-Tx and doubled on IGF-I-Tx. Both modalities of IGF-I improved determinants of hepatic insulin sensitivity, body composition and linear growth rate; however, IGF-I alone seemed to be more efficient. Copyright © 2011 S. Karger AG, Basel.

  14. Haplotypes of heparin-binding epidermal-growth-factor-like growth factor gene are associated with pre-eclampsia.

    PubMed

    Harendra, Galhenagey Gayani; Jayasekara, Rohan W; Dissanayake, Vajira H W

    2012-01-01

    Heparin-binding epidermal-growth-factor-like growth factor (HBEGF) plays an important role in placentation, including impaired placentation, the primary defect seen in pre-eclampsia. We carried out a case-control disease-association study to examine the association of single nucleotide polymorphisms (SNP) in the HBEGF gene and haplotypes defined by them with pre-eclampsia in a Sinhalese population in Sri Lanka. A total of 175 women with pre-eclampsia and 171 matched normotensive controls were genotyped for six SNP selected in silico as having putative functional effects using mass array Sequenom iplex methodology and a newly designed polymerase chain reaction-restriction fragment length polymorphism assay. The individual SNP were not associated with pre-eclampsia. The haplotypes defined by them, however, showed both predisposing (rs13385T,rs2074613G,rs2237076G,rs2074611C,rs4150196A,rs1862176A; odds ratio,1.65; 95% confidence interval1.04-2.60; P=0.032) and protective (rs13385C,rs2074613G,rs2237076A,rs2074611C,rs4150196A,rs1862176A; odds ratio,0.20; 95% confidence interval, 0.04-0.89; P=0.034) effects. These results confirm that polymorphisms in the HGEGF gene are associated with pre-eclampsia. The haplotypes are likely to exert their effects through the numerous transcription regulation factors binding to the polymorphic sites, namely GATA-1, GATA-3, MZF-1 and AML-1a. © 2011 The Authors. Journal of Obstetrics and Gynaecology Research © 2011 Japan Society of Obstetrics and Gynecology.

  15. Short stature and decreased insulin-like growth factor I (IGF-I)/growth hormone (GH)-ratio in an adult GH-deficient patient pointing to additional partial GH insensitivity due to a R179C mutation of the growth hormone receptor.

    PubMed

    Meyer, S; Ipek, M; Keth, A; Minnemann, T; von Mach, M A; Weise, A; Ittner, J R; Nawroth, P P; Plöckinger, U; Stalla, G K; Tuschy, U; Weber, M M; Kann, P H

    2007-08-01

    Genetic factors play an expanding role in understanding growth hormone (GH) disorders, therefore the German KIMS Pharmacogenetics Study was initiated with the aim of genotyping various GH-/IGF-I-axis-related genes of GH-deficient adult patients to investigate genotype:phenotype relationships and response to GH therapy. 129 consecutively enrolled GH-deficient adult patients were genotyped for variant 1 (V1) of the alternatively spliced noncoding exons in the 5'-untranslated region and for the nine coding exons of the GH receptor (GHR) gene, which obviously play a striking role in the function of the GH-IGF-I-axis. After detection of a heterozygous, non-synonymous mutation R179C in exon 6 in one single patient with acquired GH-deficiency (GHD) in late adulthood, analysis of her clinical data followed, leading to the diagnosis of mild short stature (-1.5SD). For further endocrine evaluation, five pituitary stimulation tests (arginine) of this patient were statistically compared to stimulation tests (arginine) of ten GH-deficient control patients, retrospectively. The formerly in patients with Laron syndrome and idiopathic short stature reported mutation R179C leads to an amino acid change from an arginine residue (codon CGC) to a cysteine residue (codon TGC) in position 179 of the extracellular domain of the GHR. Statistical analysis revealed significant decreased IGF-I/GH(0) ratio (p=0.004) and IGF-I/GH(max) ratio (p=0.001) of the index patient compared to the control patients, implying growth hormone resistance of the index patient at the level of the GHR, according to the detected R179C mutation. This study reports on the unusual case of a patient with mild short stature, who acquired GHD in late adulthood due to a non-secreting pituitary adenoma and get additionally diagnosed for pre-existing growth hormone insensitivity due to a formerly in two short statured patients described, single, heterozygous, non-synonymous mutation in the GHR. Our findings support the

  16. Synchronization of developmental processes and defense signaling by growth regulating transcription factors.

    PubMed

    Liu, Jinyi; Rice, J Hollis; Chen, Nana; Baum, Thomas J; Hewezi, Tarek

    2014-01-01

    Growth regulating factors (GRFs) are a conserved class of transcription factor in seed plants. GRFs are involved in various aspects of tissue differentiation and organ development. The implication of GRFs in biotic stress response has also been recently reported, suggesting a role of these transcription factors in coordinating the interaction between developmental processes and defense dynamics. However, the molecular mechanisms by which GRFs mediate the overlaps between defense signaling and developmental pathways are elusive. Here, we report large scale identification of putative target candidates of Arabidopsis GRF1 and GRF3 by comparing mRNA profiles of the grf1/grf2/grf3 triple mutant and those of the transgenic plants overexpressing miR396-resistant version of GRF1 or GRF3. We identified 1,098 and 600 genes as putative targets of GRF1 and GRF3, respectively. Functional classification of the potential target candidates revealed that GRF1 and GRF3 contribute to the regulation of various biological processes associated with defense response and disease resistance. GRF1 and GRF3 participate specifically in the regulation of defense-related transcription factors, cell-wall modifications, cytokinin biosynthesis and signaling, and secondary metabolites accumulation. GRF1 and GRF3 seem to fine-tune the crosstalk between miRNA signaling networks by regulating the expression of several miRNA target genes. In addition, our data suggest that GRF1 and GRF3 may function as negative regulators of gene expression through their association with other transcription factors. Collectively, our data provide new insights into how GRF1 and GRF3 might coordinate the interactions between defense signaling and plant growth and developmental pathways.

  17. Localized delivery of growth factors for periodontal tissue regeneration: role, strategies, and perspectives.

    PubMed

    Chen, Fa-Ming; Shelton, Richard M; Jin, Yan; Chapple, Iain L C

    2009-05-01

    Difficulties associated with achieving predictable periodontal regeneration, means that novel techniques need to be developed in order to regenerate the extensive soft and hard tissue destruction that results from periodontitis. Localized delivery of growth factors to the periodontium is an emerging and versatile therapeutic approach, with the potential to become a powerful tool in future regenerative periodontal therapy. Optimized delivery regimes and well-defined release kinetics appear to be logical prerequisites for safe and efficacious clinical application of growth factors and to avoid unwanted side effects and toxicity. While adequate concentrations of growth factor(s) need to be appropriately localized, delivery vehicles are also expected to possess properties such as protein protection, precision in controlled release, biocompatibility and biodegradability, self-regulated therapeutic activity, potential for multiple delivery, and good cell/tissue penetration. Here, current knowledge, recent advances, and future possibilities of growth factor delivery strategies are outlined for periodontal regeneration. First, the role of those growth factors that have been implicated in the periodontal healing/regeneration process, general requirements for their delivery, and the different material types available are described. A detailed discussion follows of current strategies for the selection of devices for localized growth factor delivery, with particular emphasis placed upon their advantages and disadvantages and future prospects for ongoing studies in reconstructing the tooth supporting apparatus.

  18. Neurodevelopmental effects of insulin-like growth factor signaling

    PubMed Central

    O’Kusky, John; Ye, Ping

    2012-01-01

    Insulin-like growth factor (IGF) signaling greatly impacts the development and growth of the central nervous system (CNS). IGF-I and IGF-II, two ligands of the IGF system, exert a wide variety of actions both during development and in adulthood, promoting the survival and proliferation of neural cells. The IGFs also influence the growth and maturation of neural cells, augmenting dendritic growth and spine formation, axon outgrowth, synaptogenesis, and myelination. Specific IGF actions, however, likely depend on cell type, developmental stage, and local microenvironmental milieu within the brain. Emerging research also indicates that alterations in IGF signaling likely contribute to the pathogenesis of some neurological disorders. This review summarizes experimental studies and shed light on the critical roles of IGF signaling, as well as its mechanisms, during CNS development. PMID:22710100

  19. Production of Multiple Growth Factors by a Newly Established Human Thyroid Carcinoma Cell Line

    PubMed Central

    Yoshida, Yataro; Ohashi, Kensaku; Sano, Emiko; Kobayashi, Hisataka; Endo, Keigo; Naruto, Masanobu; Nakamura, Toru

    1992-01-01

    A multiple growth factor‐producing tumor cell line (NIM‐1) was newly established from a patient with thyroid cancer and remarkable neutrophilia. NIM‐1 cells also caused severe neutrophilia in nude mice bearing tumors. NIM‐1‐conditioned medium (NIM‐1CM) contained activities that supported not only granulocyte, macrophage and eosinophil colony formation of human bone marrow cells but also the growth of colony‐stimulating factor (CSF)‐dependent cell lines, NFS60‐KX and TF‐1. Northern blot hybridization analysis revealed the constitutive expression of granulocyte‐CSF (G‐CSF), granulocyte/macrophage‐CSF (GM‐CSF) and interleukin(IL)‐6 mRNAs in NIM‐1 cells. Enzyme‐linked immunosorbent assays (ELISA) using NIM‐1CM also confirmed the production of IL‐la and a small amount of IL‐1β besides G‐CSF, GM‐CSF and IL‐6 in NIM‐1 cells. In addition, unexpected production of IL‐11 in NIM‐1 cells was detected by northern blot hybridization analysis and by bioassay using an IL‐11‐dependent cell line. Therefore, NIM‐1 cell line is shown to produce multiple cytokines including potentially megakaryopoietic growth factors such as GM‐CSF, IL‐6 and IL‐11. PMID:1372885

  20. Does L-arginine induce intestinal adaptation by epithelial growth factor?

    PubMed

    Camli, Alparslan; Barlas, Meral; Yagmurlu, Aydin

    2005-01-01

    To evaluate whether L-Arginine has an effect on endogenous epidermal growth factor secretion and intestinal adaptation in massive small bowel resection an experimental study was performed. Fourteen albino Wistar rats weighing 250-300 g were used for the study. After performing 50% small bowel resection and anastomosis the rats were randomly divided into two groups. The first group received 500 mg/kg/day of L-Arginine intraperitoneally for 14 days just after the surgical procedure. The control group received isotonic saline instead. Body weight measurement was preformed daily. At the end of the second postoperative week all rats underwent relaparotomy. Small bowel was resected for histopathological examination. Levels of epidermal growth factor were measured by enzyme-linked immunosorbent assay in serum, saliva, and urine at the end of second postoperative week in both groups. The weight gain was higher in the L-Arginine treated group (P < 0.05). Serum, saliva and urinary epidermal growth factor levels were significantly higher at the end of the second week compared to the control group (P < 0.05). The villus height was higher on histopathological examination in L-Arginine treated group compared to the control group (P < 0.05). L-Arginine resulted in a better intestinal adaptation after massive bowel resection. The high levels of epidermal growth factor in body fluids of L-Arginine treated rats could be the explanation for this effect.

  1. Assessing the Factors of Regional Growth Decline of Sugar Maple

    NASA Astrophysics Data System (ADS)

    Bishop, D. A.; Beier, C. M.; Pederson, N.; Lawrence, G. B.; Stella, J. C.; Sullivan, T. J.

    2014-12-01

    Sugar maple (Acer saccharum Marsh) is among the most ecologically, economically and culturally important trees in North America, but has experienced a decline disease across much of its range. We investigated the climatic and edaphic factors associated with A. saccharum growth in the Adirondack Mountains (USA) using a well-replicated tree-ring network incorporating a range of soil fertility (base cation availability). We found that nearly 3 in 4 A. saccharum trees exhibited declining growth rates during the last several decades, regardless of tree age or size. Although diameter growth was consistently higher on base-rich soils, the negative trends in growth were largely consistent across the soil chemistry gradient. Sensitivity of sugar maple growth to climatic variability was overall weaker than expected, but were also non-stationary during the 20th century. We observed increasingly positive responses to late-winter precipitation, increasingly negative responses to growing season temperatures, and strong positive responses to moisture availability during the 1960s drought that became much weaker during the recent pluvial. Further study is needed of these factors and their interactions as potential mechanisms for sugar maple growth decline.

  2. Combined inhibition of EMMPRIN and epidermal growth factor receptor prevents the growth and migration of head and neck squamous cell carcinoma cells.

    PubMed

    Suzuki, Shinsuke; Ishikawa, Kazuo

    2014-03-01

    It has been reported that the epidermal growth factor receptor (EGFR) expression is associated with the extracellular matrix metalloproteinase inducer (EMMPRIN) in some solid tumors; however, the relationship of EMMPRIN with EGFR in head and neck cancers is not fully understood. To determine the relationship between EMMPRIN and EGFR in head and neck squamous cell carcinoma (HNSCC), HNSCC cells were stimulated with epidermal growth factor (EGF), a ligand of EGFR. EMMPRIN expression in HNSCC cells was upregulated by EGF. In addition, EGF stimulation induced HNSCC cell invasion and MMP-9 expression. This increase in invasion and MMP-9 expression was abrogated by downmodulation of EMMPRIN. Furthermore, to determine the effects of combined EMMPRIN and EGFR targeting in HNSCC, HNSCC cells were treated with an EMMPRIN function-blocking antibody and the EGFR inhibitor AG1478. This combined treatment resulted in greater inhibition of HNSCC cell proliferation and migration compared with the individual agents alone. These results suggest that EMMPRIN mediates EGFR-induced tumorigenicity and that combined targeting of EMMPRIN and EGFR may be an efficacious treatment approach.

  3. Evidence for disturbed insulin and growth hormone signaling as potential risk factors in the development of schizophrenia.

    PubMed

    van Beveren, N J M; Schwarz, E; Noll, R; Guest, P C; Meijer, C; de Haan, L; Bahn, S

    2014-08-26

    Molecular abnormalities in metabolic, hormonal and immune pathways are present in peripheral body fluids of a significant subgroup of schizophrenia patients. The authors have tested whether such disturbances also occur in psychiatrically ill and unaffected siblings of schizophrenia patients with the aim of identifying potential contributing factors to disease vulnerability. The subjects were recruited as part of the Genetic Risk and OUtcome of Psychosis (GROUP) study. The authors used multiplexed immunoassays to measure the levels of 184 molecules in serum from 112 schizophrenia patients, 133 siblings and 87 unrelated controls. Consistent with the findings of previous studies, serum from schizophrenia patients contained higher levels of insulin, C-peptide and proinsulin, decreased levels of growth hormone and altered concentrations of molecules involved in inflammation. In addition, significant differences were found in the levels of some of these proteins in siblings diagnosed with mood disorders (n=16) and in unaffected siblings (n=117). Most significantly, the insulin/growth hormone ratio was higher across all groups compared with the controls. Taken together, these findings suggest the presence of a molecular endophenotype involving disruption of insulin and growth factor signaling pathways as an increased risk factor for schizophrenia.

  4. Nerve growth factor injected into the gastric ulcer base incorporates into endothelial, neuronal, glial and epithelial cells: implications for angiogenesis, mucosal regeneration and ulcer healing.

    PubMed

    Tanigawa, T; Ahluwalia, A; Watanabe, T; Arakawa, T; Tarnawski, A S

    2015-08-01

    A previous study has demonstrated that locally administered growth factors such as epidermal growth factor, basic fibroblast growth factor and hepatocyte growth factor can accelerate healing of experimental gastric ulcers in rats. That study indicates that locally administered growth factors can exert potent biological effects resulting in enhanced gastric ulcers healing. However, the fate of injected growth factors, their retention and localization to specific cellular compartments have not been examined. In our preliminary study, we demonstrated that local injection of nerve growth factor to the base of experimental gastric ulcers dramatically accelerates ulcer healing, increases angiogenesis - new blood vessel formation, and improves the quality of vascular and epithelial regeneration. Before embarking on larger, definitive and time sequence studies, we wished to determine whether locally injected nerve growth factor is retained in gastric ulcer's tissues and taken up by specific cells during gastric ulcer healing. Gastric ulcers were induced in anesthetized rats by local application of acetic acid using standard methods; and, 60 min later fluorescein isothiocyanate-labeled nerve growth factor was injected locally to the ulcer base. Rats were euthanized 2, 5 and 10 days later. Gastric specimens were obtained and processed for histology. Unstained paraffin sections were examined under a fluorescence microscope, and the incorporation of fluorescein isothiocyanate-labeled nerve growth factor into various gastric tissue cells was determined and quantified. In addition, we performed immunostaining for S100β protein that is expressed in neural components. Five and ten days after ulcer induction labeled nerve growth factor (injected to the gastric ulcer base) was incorporated into endothelial cells of blood vessels, neuronal, glial and epithelial cells, myofibroblasts and muscle cells. This study demonstrates for the first time that during gastric ulcer healing

  5. Some growth factors stimulate cultured adult rabbit ventricular myocyte hypertrophy in the absence of mechanical loading

    NASA Technical Reports Server (NTRS)

    Decker, R. S.; Cook, M. G.; Behnke-Barclay, M.; Decker, M. L.

    1995-01-01

    Cultured adult rabbit cardiac myocytes treated with recombinant growth factors display enhanced rates of protein accumulation (ie, growth) in response to insulin and insulin-like growth factors (IGFs), but epidermal growth factor, acidic or basic fibroblast growth factor, and platelet-derived growth factor failed to increase contractile protein synthesis or growth of the heart cells. Insulin and IGF-1 increased growth rates by stimulating anabolic while simultaneously inhibiting catabolic pathways, whereas IGF-2 elevated growth modestly by apparently inhibiting lysosomal proteolysis. Neutralizing antibodies directed against either IGF-1 or IGF-2 or IGF binding protein 3 blocked protein accumulation. A monoclonal antibody directed against the IGF-1 receptor also inhibited changes in protein turnover provoked by recombinant human IGF-1 but not IGF-2. Of the other growth factors tested, only transforming growth factor-beta 1 increased the fractional rate of myosin heavy chain (MHC) synthesis, with beta-MHC synthesis being elevated and alpha-MHC synthesis being suppressed. However, the other growth factors were able to modestly stimulate the rate of DNA synthesis in this preparation. Bromodeoxyuridine labeling revealed that these growth factors increased DNA synthesis in myocytes and nonmyocytes alike, but the heart cells displayed neither karyokinesis or cytokinesis. In contrast, cocultures of cardiac myocytes and nonmyocytes and nonmyocyte-conditioned culture medium failed to enhance the rate of cardiac MHC synthesis or its accumulation, implying that quiescent heart cells do not respond to "conditioning" by cardiac nonmyocytes. These findings demonstrated that insulin and the IGFs promote passively loaded cultured adult rabbit heart cells to hypertrophy but suggest that other growth factors tested may be limited in this regard.

  6. Epidermal growth factor impairs palatal shelf adhesion and fusion in the Tgf-β 3 null mutant.

    PubMed

    Barrio, M Carmen; Del Río, Aurora; Murillo, Jorge; Maldonado, Estela; López-Gordillo, Yamila; Paradas-Lara, Irene; Hernandes, Luzmarina; Catón, Javier; Martínez-Álvarez, Concepción

    2014-01-01

    The cleft palate presented by transforming growth factor-β3 (Tgf-β3) null mutant mice is caused by altered palatal shelf adhesion, cell proliferation, epithelial-to-mesenchymal transformation and cell death. The expression of epidermal growth factor (EGF), transforming growth factor-β1 (Tgf-β1) and muscle segment homeobox-1 (Msx-1) is modified in the palates of these knockout mice, and the cell proliferation defect is caused by the change in EGF expression. In this study, we aimed to determine whether this change in EGF expression has any effect on the other mechanisms altered in Tgf-β3 knockout mouse palates. We tested the effect of inhibiting EGF activity in vitro in the knockout palates via the addition of Tyrphostin AG 1478. We also investigated possible interactions between EGF, Tgf-β1 and Msx-1 in Tgf-β3 null mouse palate cultures. The results show that the inhibition of EGF activity in Tgf-β3 null mouse palate cultures improves palatal shelf adhesion and fusion, with a particular effect on cell death, and restores the normal distribution pattern of Msx-1 in the palatal mesenchyme. Inhibition of TGF-β1 does not affect either EGF or Msx-1 expression. © 2014 S. Karger AG, Basel.

  7. Blockade of epidermal growth factor receptor signaling leads to inhibition of renal cell carcinoma growth in the bone of nude mice.

    PubMed

    Weber, Kristy L; Doucet, Michele; Price, Janet E; Baker, Cheryl; Kim, Sun Jin; Fidler, Isaiah J

    2003-06-01

    Renal cell carcinoma (RCC) frequently produces metastases to the musculoskeletal system that are a major source of morbidity in the form of pain, immobilization, fractures, neurological compromise, and a decreased ability to perform activities of daily living. Patients with metastatic RCC therefore have a dismal prognosis because there is no effective adjuvant treatment for this disease. Because the epidermal growth factor receptor (EGF-R) signaling cascade is important in the growth and metastasis of RCC, its blockade has been hypothesized to inhibit tumor growth and hence prevent resultant bone destruction. We determined whether blockade of EGF-R by the tyrosine kinase inhibitor PKI 166 inhibited the growth of RCC in bone. We use a novel cell line, RBM1-IT4, established from a human RCC bone metastasis. Protein and mRNA expression of the ligands and receptors was assessed by Western and Northern blots. The stimulation of RBM1-IT4 cells with epidermal growth factor or transforming growth factor alpha resulted in increased cellular proliferation and tyrosine kinase autophosphorylation. PKI 166 prevented these effects. First, RBM1-IT4 cells were implanted into the tibia of nude mice, where they established lytic, progressively growing lesions, after which the mice were treated with PKI 166 alone or in combination with paclitaxel (Taxol). Immunohistochemical analysis revealed that tumor cells and tumor-associated endothelial cells in control mice expressed activated EGF-R. Treatment of mice with PKI 166 alone or in combination with Taxol produced a significant decrease in the incidence and size of bone lesions as compared with the results in control or Taxol-treated mice (P < 0.001). Treatment with PKI 166 also decreased the expression of phosphorylated EGF-R by tumor cells and tumor-associated endothelial cells, and this was even more pronounced with PKI 166 plus Taxol treatment. The PKI 166 plus Taxol combination produced apoptosis of tumor cells and tumor

  8. Hematopoietic growth factors and human acute leukemia.

    PubMed

    Löwenberg, B; Touw, I

    1988-10-22

    The study of myelopoietic maturation arrest in acute myeloblastic leukemia (AML) has been eased by availability of the human recombinant hemopoietic growth factors, macrophage colony stimulating factor (M-CSF), granulocyte-(G-CSF), granulocyte-macrophage-(GM-CSF) and multilineage stimulating factor (IL-3). Nonphysiological expansion of the leukemic population is not due to escape from control by these factors. Proliferation in vitro of AML cells is dependent on the presence of one or several factors in most cases. The pattern of factor-dependency does not correlate with morphological criteria in individual cases, and may thus offer a new tool for classification of AML. Overproduction of undifferentiated cells is not due to abnormal expression of receptors for the stimulating factors acting at an immature level. Rather, autocrine secretion of early acting lymphokines maintains proliferation of the leukemic clone. When looking at causes of leukemic dysregulation, yet undefined inhibitors of differentiation probably are of equal importance as dysequilibrated stimulation by lymphokines.

  9. The effect of pasteurization on transforming growth factor alpha and transforming growth factor beta 2 concentrations in human milk.

    PubMed

    McPherson, R J; Wagner, C L

    2001-01-01

    Transforming growth factor alpha (TGF-alpha) and beta 2 (TGF-beta2) are present in human milk and are involved in growth differentiation and repair of neonatal intestinal epithelia. Heat treatment at 56 degrees C has been shown effective for providing safe banked donor milk, with good retention of other biologically active factors. The purpose of our study was to determine the effect of heat sterilization on TGF-alpha and TGF-beta2 concentrations in human milk. Twenty milk samples were collected from 20 lactating mothers in polypropylene containers and frozen at -20 degrees C for transport or storage. Before heat treatment by holder pasteurization, the frozen milk was thawed and divided into 1-mL aliquots. All samples were heated in an accurately regulated water bath until a holding temperature was achieved, then held for 30 minutes using constant agitation. Holding temperature ranged from 56.5 degrees C to 56.9 degrees C. The milk was then stored at 4 degrees C overnight for analysis the following day. The concentration of TGF-alpha was measured by radioimmunoassay. Mean concentration +/- SD of TGF-alpha in raw milk samples was 119+/-50 pg/mL, range 57 to 234. The mean concentration +/- SD of TGF-alpha in heat treated samples was 113+/-50 pg/mL, range 51 to 227. TGF-alpha concentration was minimally affected by pasteurization, with an overall loss of 6.1%. Of 19 samples, 4 had increased and 15 had decreased concentrations after pasteurization (mean percent SEM: 94%+/-7% of raw milk, range 72%+/-107%). The concentration of acid-activated TGF-beta2 was measured by enzyme-linked immunosorbent assay. Mean concentration +/- SD of TGF-beta2 in raw milk samples was 5624+/-5038 pg/mL, range 195 to 15480. The mean concentration +/- SD of TGF-beta2 in heat-treated samples was 5073+/-4646 pg/mL, range 181 to 15140. TGF-beta2 survived with relatively little loss (0.6%): of 18 samples, 11 had increased and 7 had decreased concentrations after pasteurization (mean percent

  10. Connective tissue growth factor stimulates the proliferation, migration and differentiation of lung fibroblasts during paraquat-induced pulmonary fibrosis

    PubMed Central

    YANG, ZHIZHOU; SUN, ZHAORUI; LIU, HONGMEI; REN, YI; SHAO, DANBING; ZHANG, WEI; LIN, JINFENG; WOLFRAM, JOY; WANG, FENG; NIE, SHINAN

    2015-01-01

    It is well established that paraquat (PQ) poisoning can cause severe lung injury during the early stages of exposure, finally leading to irreversible pulmonary fibrosis. Connective tissue growth factor (CTGF) is an essential growth factor that is involved in tissue repair and pulmonary fibrogenesis. In the present study, the role of CTGF was examined in a rat model of pulmonary fibrosis induced by PQ poisoning. Histological examination revealed interstitial edema and extensive cellular thickening of interalveolar septa at the early stages of poisoning. At 2 weeks after PQ administration, lung tissue sections exhibited a marked thickening of the alveolar walls with an accumulation of interstitial cells with a fibroblastic appearance. Masson’s trichrome staining revealed a patchy distribution of collagen deposition, indicating pulmonary fibrogenesis. Western blot analysis and immunohistochemical staining of tissue samples demonstrated that CTGF expression was significantly upregulated in the PQ-treated group. Similarly, PQ treatment of MRC-5 human lung fibroblast cells caused an increase in CTGF in a dose-dependent manner. Furthermore, the addition of CTGF to MRC-5 cells triggered cellular proliferation and migration. In addition, CTGF induced the differentiation of fibroblasts to myofibroblasts, as was evident from increased expression of α-smooth muscle actin (α-SMA) and collagen. These findings demonstrate that PQ causes increased CTGF expression, which triggers proliferation, migration and differentiation of lung fibroblasts. Therefore, CTGF may be important in PQ-induced pulmonary fibrogenesis, rendering this growth factor a potential pharmacological target for reducing lung injury. PMID:25815693

  11. Connective tissue growth factor stimulates the proliferation, migration and differentiation of lung fibroblasts during paraquat-induced pulmonary fibrosis.

    PubMed

    Yang, Zhizhou; Sun, Zhaorui; Liu, Hongmei; Ren, Yi; Shao, Danbing; Zhang, Wei; Lin, Jinfeng; Wolfram, Joy; Wang, Feng; Nie, Shinan

    2015-07-01

    It is well established that paraquat (PQ) poisoning can cause severe lung injury during the early stages of exposure, finally leading to irreversible pulmonary fibrosis. Connective tissue growth factor (CTGF) is an essential growth factor that is involved in tissue repair and pulmonary fibrogenesis. In the present study, the role of CTGF was examined in a rat model of pulmonary fibrosis induced by PQ poisoning. Histological examination revealed interstitial edema and extensive cellular thickening of interalveolar septa at the early stages of poisoning. At 2 weeks after PQ administration, lung tissue sections exhibited a marked thickening of the alveolar walls with an accumulation of interstitial cells with a fibroblastic appearance. Masson's trichrome staining revealed a patchy distribution of collagen deposition, indicating pulmonary fibrogenesis. Western blot analysis and immunohistochemical staining of tissue samples demonstrated that CTGF expression was significantly upregulated in the PQ-treated group. Similarly, PQ treatment of MRC-5 human lung fibroblast cells caused an increase in CTGF in a dose-dependent manner. Furthermore, the addition of CTGF to MRC-5 cells triggered cellular proliferation and migration. In addition, CTGF induced the differentiation of fibroblasts to myofibroblasts, as was evident from increased expression of α-smooth muscle actin (α-SMA) and collagen. These findings demonstrate that PQ causes increased CTGF expression, which triggers proliferation, migration and differentiation of lung fibroblasts. Therefore, CTGF may be important in PQ-induced pulmonary fibrogenesis, rendering this growth factor a potential pharmacological target for reducing lung injury.

  12. Hepatocyte growth factor induces resistance to anti-epidermal growth factor receptor antibody in lung cancer.

    PubMed

    Yamada, Tadaaki; Takeuchi, Shinji; Kita, Kenji; Bando, Hideaki; Nakamura, Takahiro; Matsumoto, Kunio; Yano, Seiji

    2012-02-01

    Epidermal growth factor receptor (EGFR) is an attractive drug target in lung cancer, with several anti-EGFR antibodies and small-molecule inhibitors showing efficacy in lung cancer patients. Patients, however, may develop resistance to EGFR inhibitors. We demonstrated previously that hepatocyte growth factor (HGF) induced resistance to EGFR tyrosine kinase inhibitors in lung cancers harboring EGFR mutations. We therefore determined whether HGF could induce resistance to the anti-EGFR antibody (EGFR Ab) cetuximab in lung cancer cells, regardless of EGFR gene status. Cetuximab sensitivity and signal transduction in lung cancer cells were examined in the presence or absence of HGF, HGF-producing fibroblasts, and cells tranfected with the HGF gene in vitro and in vivo. HGF induced resistance to cetuximab in H292 (EGFR wild) and Ma-1(EGFR mutant) cells. Western blotting showed that HGF-induced resistance was mediated by the Met/Gab1/Akt signaling pathway. Resistance of H292 and Ma-1 cells to cetuximab was also induced by coculture with lung fibroblasts producing high levels of HGF and by cells stably transfected with the HGF gene. This resistance was abrogated by treatment with anti-HGF neutralizing antibody. HGF-mediated resistance is a novel mechanism of resistance to EGFR Ab in lung cancers, with fibroblast-derived HGF inducing cetuximab resistance in H292 tumors in vivo. The involvement of HGF-Met-mediated signaling should be assessed in acquired resistance to EGFR Ab in lung cancer, regardless of EGFR gene status.

  13. Growth factor deprivation induces cytosolic translocation of SIRT1

    NASA Astrophysics Data System (ADS)

    Meng, Chengbo; Xing, Da; Wu, Shengnan; Huang, Lei

    2010-02-01

    Sirtuin type 1 (SIRT1), a NAD+-dependent histone deacetylases, plays a critical role in cellular senescence, aging and longevity. In general, SIRT1 is localized in nucleus and is believed as a nuclear protein. Though overexpression of SIRT1 delays senescence, SIRT1-protein levels decline naturally in thymus and heart during aging. In the present studies, we investigated the subcellular localization of SIRT1 in response to growth factor deprivation in African green monkey SV40-transformed kidney fibroblast cells (COS-7). Using SIRT1-EGFP fluorescence reporter, we found that SIRT1 localized to nucleus in physiological conditions. We devised a model enabling cell senescence via growth factor deprivation, and we found that SIRT1 partially translocated to cytosol under the treatment, suggesting a reduced level of SIRT1's activity. We found PI3K/Akt pathway was involved in the inhibition of SIRT1's cytosolic translocation, because inhibition of these kinases significantly decreased the amount of SIRT1 maintained in nucleus. Taken together, we demonstrated that growth factor deprivation induces cytosolic translocation of SIRT1, which suggesting a possible connection between cytoplasm-localized SIRT1 and the aging process.

  14. Growth hormone and insulin-like growth factors in fish: Where we are and where to go

    USGS Publications Warehouse

    Reinecke, M.; Bjornsson, Bjorn Thrandur; Dickhoff, Walton W.; McCormick, S.D.; Navarro, I.; Power, D.M.; Gutierrez, J.

    2005-01-01

    This communication summarizes viewpoints, discussion, perspectives, and questions, put forward at a workshop on "Growth hormone and insulin-like growth factors in fish" held on September 7th, 2004, at the 5th International Symposium on Fish Endocrinology in Castello??n, Spain. ?? 2005 Elsevier Inc. All rights reserved.

  15. Collagen and Stretch Modulate Autocrine Secretion of Insulin-like Growth Factor-1 and Insulin-like Growth Factor Binding Proteins from Differentiated Skeletal Muscle Cells

    NASA Technical Reports Server (NTRS)

    Perrone, Carmen E.; Fenwick-Smith, Daniela; Vandenburgh, Herman H.

    1995-01-01

    Stretch-induced skeletal muscle growth may involve increased autocrine secretion of insulin-like growth factor-1 (IGF-1) since IGF-1 is a potent growth factor for skeletal muscle hypertrophy, and stretch elevates IGF-1 mRNA levels in vivo. In tissue cultures of differentiated avian pectoralis skeletal muscle cells, nanomolar concentrations of exogenous IGF-1 stimulated growth in mechanically stretched but not static cultures. These cultures released up to 100 pg of endogenously produced IGF-1/micro-g of protein/day, as well as three major IGF binding proteins of 31, 36, and 43 kilodaltons (kDa). IGF-1 was secreted from both myofibers and fibroblasts coexisting in the muscle cultures. Repetitive stretch/relaxation of the differentiated skeletal muscle cells stimulated the acute release of IGF-1 during the first 4 h after initiating mechanical activity, but caused no increase in the long-term secretion over 24-72 h of IGF-1, or its binding proteins. Varying the intensity and frequency of stretch had no effect on the long-term efflux of IGF-1. In contrast to stretch, embedding the differentiated muscle cells in a three-dimensional collagen (Type I) matrix resulted in a 2-5-fold increase in long-term IGF-1 efflux over 24-72 h. Collagen also caused a 2-5-fold increase in the release of the IGF binding proteins. Thus, both the extracellular matrix protein type I collagen and stretch stimulate the autocrine secretion of IGF-1, but with different time kinetics. This endogenously produced growth factor may be important for the growth response of skeletal myofibers to both types of external stimuli.

  16. Fibroblast growth factor receptor 4 (FGFR4) and fibroblast growth factor 19 (FGF19) autocrine enhance breast cancer cells survival.

    PubMed

    Tiong, Kai Hung; Tan, Boon Shing; Choo, Heng Lungh; Chung, Felicia Fei-Lei; Hii, Ling-Wei; Tan, Si Hoey; Khor, Nelson Tze Woei; Wong, Shew Fung; See, Sze-Jia; Tan, Yuen-Fen; Rosli, Rozita; Cheong, Soon-Keng; Leong, Chee-Onn

    2016-09-06

    Basal-like breast cancer is an aggressive tumor subtype with poor prognosis. The discovery of underlying mechanisms mediating tumor cell survival, and the development of novel agents to target these pathways, is a priority for patients with basal-like breast cancer. From a functional screen to identify key drivers of basal-like breast cancer cell growth, we identified fibroblast growth factor receptor 4 (FGFR4) as a potential mediator of cell survival. We found that FGFR4 mediates cancer cell survival predominantly via activation of PI3K/AKT. Importantly, a subset of basal-like breast cancer cells also secrete fibroblast growth factor 19 (FGF19), a canonical ligand specific for FGFR4. siRNA-mediated silencing of FGF19 or neutralization of extracellular FGF19 by anti-FGF19 antibody (1A6) decreases AKT phosphorylation, suppresses cancer cell growth and enhances doxorubicin sensitivity only in the FGFR4+/FGF19+ breast cancer cells. Consistently, FGFR4/FGF19 co-expression was also observed in 82 out of 287 (28.6%) primary breast tumors, and their expression is strongly associated with AKT phosphorylation, Ki-67 staining, higher tumor stage and basal-like phenotype. In summary, our results demonstrated the presence of an FGFR4/FGF19 autocrine signaling that mediates the survival of a subset of basal-like breast cancer cells and suggest that inactivation of this autocrine loop may potentially serve as a novel therapeutic intervention for future treatment of breast cancers.

  17. Experiment K-7-22: Growth Hormone Regulation Synthesis and Secretion in Microgravity. Part 2; Hypothalamic Growth Hormone-Releasing Factor, Somatostatin Immunoreactivity, and Messenger RNA Levels in Microgravity

    NASA Technical Reports Server (NTRS)

    Sawchenko, P. E.; Arias, C.; Krasnov, I.; Grindeland, R. E.; Vale, W.

    1994-01-01

    Immunohistochemical analyses of hypothalamic hormones carried out on tissue from rats flown on an earlier flight (Cosmos 1887) suggested preferential effects on hypophysiotropic principles involved in the regulation of growth hormone secretion and synthesis. We found that staining in the median eminence for peptides that provide both stimulatory (growth hormone-releasing factor, or GRF) and inhibitory (somatostatin, SS) influences on growth hormone secretion were depressed in flight animals relative to synchronous controls, while staining for other neuroendocrine peptides, cortocotropin-releasing factor and arginine vasopressin, were similar in these two groups. While this suggests some selective impact of weightlessness on the two principal central nervous system regulators of growth hormone dynamics, the fact that both GRF- and SS-immunoreactivity (IR) appeared affected in the same direction is somewhat problematic, and makes tentative any intimation that effects on CNS control mechanisms may be etiologically significant contributors to the sequelae of reduced growth hormone secretion seen in prolonged space flight. To provide an additional, and more penetrating, analysis we attempted in hypothalamic material harvested from animals flown on Cosmos 2044 to complement immunohistochemical analyses of GRF and SS staining with quantitative, in situ assessments of messenger RNAs encoding the precursors for both these hormones.

  18. Inhibition of Epidermal Growth Factor Receptor and Vascular Endothelial Growth Factor Receptor Phosphorylation on Tumor-Associated Endothelial Cells Leads to Treatment of Orthotopic Human Colon Cancer in Nude Mice1

    PubMed Central

    Sasaki, Takamitsu; Kitadai, Yasuhiko; Nakamura, Toru; Kim, Jang-Seong; Tsan, Rachel Z; Kuwai, Toshio; Langley, Robert R; Fan, Dominic; Kim, Sun-Jin; Fidler, Isaiah J

    2007-01-01

    The purpose of our study was to determine whether the dual inhibition of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor (VEGFR) signaling pathways in tumor-associated endothelial cells can inhibit the progressive growth of human colon carcinoma in the cecum of nude mice. SW620CE2 human colon cancer cells growing in culture and orthotopically in the cecum of nude mice expressed a high level of transforming growth factor alpha (TGF-α) and vascular endothelial growth factor (VEGF) but were negative for EGFR, human epidermal growth factor receptor 2 (HER2), and VEGFR. Double immunofluorescence staining revealed that tumor-associated endothelial cells expressed EGFR, VEGFR2, phosphorylated EGFR (pEGFR), and phosphorylated VEGFR (pVEGFR). Treatment of mice with either 7H-pyrrolo [2,3-d]-pyrimidine lead scaffold (AEE788; an inhibitor of EGFR and VEGFR tyrosine kinase) or CPT-11 as single agents significantly inhibited the growth of cecal tumors (P < .01); this decrease was even more pronounced with AEE788 combined with CPT-11 (P < .001). AEE788 alone or combined with CPT-11 also inhibited the expression of pEGFR and pVEGFR on tumor-associated endothelial cells, significantly decreased vascularization and tumor cell proliferation, and increased the level of apoptosis in both tumor-associated endothelial cells and tumor cells. These data demonstrate that targeting EGFR and VEGFR signaling on tumor-associated endothelial cells provides a viable approach for the treatment of colon cancer. PMID:18084614

  19. Clinical and biological significance of hepatoma-derived growth factor in Ewing's sarcoma.

    PubMed

    Yang, Yang; Li, Hui; Zhang, Fenfen; Shi, Huijuan; Zhen, Tiantian; Dai, Sujuan; Kang, Lili; Liang, Yingjie; Wang, Jin; Han, Anjia

    2013-11-01

    We sought to investigate the clinicopathological significance and biological function of hepatoma-derived growth factor (HDGF) in Ewing's sarcoma. Our results showed that HDGF expression is up-regulated in Ewing's sarcoma. Nuclear HDGF expression is significantly associated with tumour volume (p < 0.001), metastases at diagnosis (p < 0.001), low overall survival rate (p < 0.001) and low disease-free survival rate (p < 0.001). HDGF knock-down results in significant reduction of Ewing's sarcoma cell growth, proliferation and enhances tumourigenesis, both in vitro and in vivo. Meanwhile, HDGF knock-down causes cell cycle arrest and enhanced sensitization to serum starvation-induced apoptosis. Furthermore, recombinant HDGF promotes proliferation and colony formation of Ewing's sarcoma cells. Ninety-eight candidate HDGF downstream genes were identified in Ewing's sarcoma cells using cDNA microarray analysis. In addition, we found that HDGF knock-down inhibited FLI1 expression in Ewing's sarcoma cells at the mRNA and protein levels. Our findings suggest that HDGF exhibits oncogenic properties and may be a novel prognostic factor in Ewing's sarcoma. Targeting HDGF might be a potential therapeutic strategy for Ewing's sarcoma. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  20. [Metabolic and hemodynamic effects of the growth hormone system - insulin-like growth factor].

    PubMed

    Manhylova, T A; Gafarova, N H

    2015-01-01

    Significant congenital deficiency of growth factor (GF) results in pituitary nanism (dwarfism) and its substantial excess is accompanied by the development of gigantism or acromegaly. Its impact on the growth of the whole body or its individual parts is impossible without affecting metabolic processes and hemodynamic parameters. A number of investigations have proven that GF has a direct lipolytic effect: adequate replacement therapy for pituitary nanism gives rise to a reduction in fat depots. Since the concentration of GF is lower in obesity, Whether it may be used to treat this abnormality is considered.

  1. Decreased Plasma Brain-Derived Neurotrophic Factor and Vascular Endothelial Growth Factor Concentrations during Military Training

    PubMed Central

    Nibuya, Masashi; Ishida, Toru; Yamamoto, Tetsuo; Mukai, Yasuo; Mitani, Keiji; Tsumatori, Gentaro; Scott, Daniel; Shimizu, Kunio

    2014-01-01

    Decreased concentrations of plasma brain-derived neurotrophic factor (BDNF) and serum BDNF have been proposed to be a state marker of depression and a biological indicator of loaded psychosocial stress. Stress evaluations of participants in military mission are critically important and appropriate objective biological parameters that evaluate stress are needed. In military circumstances, there are several problems to adopt plasma BDNF concentration as a stress biomarker. First, in addition to psychosocial stress, military missions inevitably involve physical exercise that increases plasma BDNF concentrations. Second, most participants in the mission do not have adequate quality or quantity of sleep, and sleep deprivation has also been reported to increase plasma BDNF concentration. We evaluated plasma BDNF concentrations in 52 participants on a 9-week military mission. The present study revealed that plasma BDNF concentration significantly decreased despite elevated serum enzymes that escaped from muscle and decreased quantity and quality of sleep, as detected by a wearable watch-type sensor. In addition, we observed a significant decrease in plasma vascular endothelial growth factor (VEGF) during the mission. VEGF is also neurotrophic and its expression in the brain has been reported to be up-regulated by antidepressive treatments and down-regulated by stress. This is the first report of decreased plasma VEGF concentrations by stress. We conclude that decreased plasma concentrations of neurotrophins can be candidates for mental stress indicators in actual stressful environments that include physical exercise and limited sleep. PMID:24586790

  2. Constitutive Smad linker phosphorylation in melanoma: A mechanism of resistance to Transforming Growth Factor-β-mediated growth inhibition

    PubMed Central

    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

    2011-01-01

    SUMMARY 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 in 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 p15INK4B and p21WAF1, as compared with cells transfected with wild-type Smad3. In addition, the cell numbers of EPSM Smad3-expressing melanoma cells were significantly reduced compared to wild-type Smad3-expressing cells. These results suggest that the linker phosphorylation of Smad3 contributes to the resistance of melanoma cells to TGFβ-mediated growth inhibition. PMID:21477078

  3. Autocrine and/or paracrine insulin-like growth factor-I activity in skeletal muscle

    NASA Technical Reports Server (NTRS)

    Adams, Gregory R.

    2002-01-01

    Similar to bone, skeletal muscle responds and adapts to changes in loading state via mechanisms that appear to be intrinsic to the muscle. One of the mechanisms modulating skeletal muscle adaptation it thought to involve the autocrine and/or paracrine production of insulinlike growth factor-I. This brief review outlines components of the insulinlike growth factor-I system as it relates to skeletal muscle and provides the rationale for the theory that insulinlike growth factor-I is involved with muscle adaptation.

  4. Modeling invasive breast cancer: growth factors propel progression of HER2-positive premalignant lesions

    PubMed Central

    Pradeep, C-R; Zeisel, A; Köstler, WJ; Lauriola, M; Jacob-Hirsch, J; Haibe-Kains, B; Amariglio, N; Ben-Chetrit, N; Emde, A; Solomonov, I; Neufeld, G; Piccart, M; Sagi, I; Sotiriou, C; Rechavi, G; Domany, E; Desmedt, C; Yarden, Y

    2013-01-01

    The HER2/neu oncogene encodes a receptor-like tyrosine kinase whose overexpression in breast cancer predicts poor prognosis and resistance to conventional therapies. However, the mechanisms underlying aggressiveness of HER2 (human epidermal growth factor receptor 2)-overexpressing tumors remain incompletely understood. Because it assists epidermal growth factor (EGF) and neuregulin receptors, we overexpressed HER2 in MCF10A mammary cells and applied growth factors. HER2-overexpressing cells grown in extracellular matrix formed filled spheroids, which protruded outgrowths upon growth factor stimulation. Our transcriptome analyses imply a two-hit model for invasive growth: HER2-induced proliferation and evasion from anoikis generate filled structures, which are morphologically and transcriptionally analogous to preinvasive patients’ lesions. In the second hit, EGF escalates signaling and transcriptional responses leading to invasive growth. Consistent with clinical relevance, a gene expression signature based on the HER2/EGF-activated transcriptional program can predict poorer prognosis of a subgroup of HER2-overexpressing patients. In conclusion, the integration of a three-dimensional cellular model and clinical data attributes progression of HER2-overexpressing lesions to EGF-like growth factors acting in the context of the tumor's microenvironment. PMID:22139081

  5. Oocyte holding in the Iberian red deer (Cervus elaphus hispanicus): Effect of initial oocyte quality and epidermal growth factor addition on in vitro maturation.

    PubMed

    Macías-García, B; González-Fernández, L; Matilla, E; Hernández, N; Mijares, J; Sánchez-Margallo, F M

    2018-02-01

    Current in vitro embryo production protocols in the Iberian red deer (Cervus elaphus hispanicus) need to be optimized; oocyte harvesting in situ followed by overnight holding could reduce the human effort and shipping costs. In our work, post-mortem ovaries were retrieved, and the oocytes were harvested and allocated to G1 group (good quality) or G2 + G3 group (low quality). The oocytes were separately subjected to immediate in vitro maturation (IVM) or held overnight in a holding medium composed of 40% of TCM 199 with Earle's salts, 40% TCM 199 with Hanks' salts and 20% fetal bovine serum (FBS), at room temperature (16 hr). In vitro maturation was carried out in a basal medium supplemented or not with 50 ng/ml of epidermal growth factor (EGF). Our data showed that addition of EGF to the maturation medium increases the percentage of G1 oocytes reaching metaphase II (3.9% vs. 50%, basal vs. EGF; p < .001) and decreased their degeneration rate (69.9% vs. 22.2%, basal vs. EGF; p < .01) when oocytes were immediately matured. Overnight holding increased the meiotic competence of G1 oocytes (37.5% matured in basal medium) and EGF increased prophase arrest in G2 + G3 oocytes (16.1% vs. 38.8% in germinal vesicle [GV] stage in basal medium vs. EGF added medium; p < .05). Our data demonstrate that oocyte holding can be used in Iberian red deer oocytes. Interestingly, EGF addition increases the oocytes' meiotic competence in immediately matured oocytes but not after oocyte holding depending upon initial oocyte quality. © 2017 Blackwell Verlag GmbH.

  6. [Pathogenetic and Prognostic Role of Growth Factors in the Development of Chronic Heart Failure].

    PubMed

    Teplyakov, A T; Berezikova, E N; Shilov, S N; Efremova, A V; Pustovetova, M G; Popova, A A; Grakova, E V; Torim, Y Y; Safronov, I D; Andriyanova, A V

    2017-10-01

    To study the role of growth factors ((vascular endothelial growth factor (VEGF), platelet derived growth factor AB (PDGF-AB) and basic fibroblast growth factor (FGF-basic)) in the development and progression of chronic heart failure (CHF) in patients with ishcemic heart disease (IHD). We included in this study 94 patients with CHF. The control group comprised 32 persons. Blood serum levels of growth factors were determined at baseline and after 12 months of observation by enzyme-linked immunosorbent assay. VEGF, PDGF-AB and FGF-basic play an important role in the pathogenesis and progression of heart failure in patients with IHD, determining the increased risk of adverse cardiovascular events in this pathology. Serum activity of growth factors characterizes the severity and course of CHF: with disease progression levels of VEGF and FGF-basic decrease and PDGF-AB concentration increases. Initial low level of VEGF expression regardless of the sex of the patient's sex, significantly low level of FGF-basic and significantly high PDGF-AB in men characterizes unfavorable course of CHF. A correlation has been established between blood serum levels of VEGF, PDGF-AB and FGF-basic and severity and course of CHF.

  7. Inhibition of platelet-derived growth factor signaling prevents muscle fiber growth during skeletal muscle hypertrophy.

    PubMed

    Sugg, Kristoffer B; Korn, Michael A; Sarver, Dylan C; Markworth, James F; Mendias, Christopher L

    2017-03-01

    The platelet-derived growth factor receptors alpha and beta (PDGFRα and PDGFRβ) mark fibroadipogenic progenitor cells/fibroblasts and pericytes in skeletal muscle, respectively. While the role that these cells play in muscle growth and development has been evaluated, it was not known whether the PDGF receptors activate signaling pathways that control transcriptional and functional changes during skeletal muscle hypertrophy. To evaluate this, we inhibited PDGFR signaling in mice subjected to a synergist ablation muscle growth procedure, and performed analyses 3 and 10 days after induction of hypertrophy. The results from this study indicate that PDGF signaling is required for fiber hypertrophy, extracellular matrix production, and angiogenesis that occur during muscle growth. © 2017 Federation of European Biochemical Societies.

  8. A potential oncogenic activity of platelet-derived growth factor d in prostate cancer progression.

    PubMed

    Ustach, Carolyn V; Taube, Marcus E; Hurst, Newton J; Bhagat, Sunita; Bonfil, R Daniel; Cher, Michael L; Schuger, Lucia; Kim, Hyeong-Reh Choi

    2004-03-01

    The platelet-derived growth factor (PDGF) proteins are potent stimulators of cell proliferation/transformation and play a major role in cell-cell communication. For over two decades, PDGFs were thought to exist as three dimeric polypeptides (the homodimers AA and BB and the heterodimer AB). Recently, however, the PDGF C and D chains were discovered in a BLAST search of the expressed sequence tag databases. The PDGF CC and DD dimers have a unique two-domain structure with an NH(2)-terminal CUB (compliment subcomponents C1r/C1s, Uegf, and Bmp1) domain and a COOH-terminal PDGF/vascular endothelial growth factor domain. Whereas secreted PDGF AA, BB, and AB readily activate their cell surface receptors, it was suggested that extracellular proteolytic removal of the CUB domain is required for the PDGF/vascular endothelial growth factor domain of PDGF CC and DD to activate PDGF receptors. In the present study, we examined the processing of latent PDGF D into its active form and the effects of PDGF D expression on prostate cancer progression. We show that LNCaP cells auto-activate latent PDGF DD into the active PDGF domain, which can induce phosphorylation of the beta-PDGF receptor and stimulates LNCaP cell proliferation in an autocrine manner. Additionally, LNCaP-PDGF D-conditioned medium induces migration of the prostate fibroblast cell line 1532-FTX, indicating LNCaP-processed PDGF DD is active in a paracrine manner as well. In a severe combined immunodeficient mouse model, PDGF DD expression accelerates early onset of prostate tumor growth and drastically enhances prostate carcinoma cell interaction with surrounding stromal cells. These demonstrate a potential oncogenic activity of PDGF DD in the development and/or progression of prostate cancer.

  9. A Potential Oncogenic Activity of Platelet-Derived Growth Factor D in Prostate Cancer Progression

    PubMed Central

    Ustach, Carolyn V.; Taube, Marcus E.; Hurst, Newton J.; Bhagat, Sunita; Bonfil, R. Daniel; Cher, Michael L.; Schuger, Lucia; Kim, Hyeong-Reh Choi

    2014-01-01

    The platelet-derived growth factor (PDGF) proteins are potent stimulators of cell proliferation/transformation and play a major role in cell-cell communication. For over two decades, PDGFs were thought to exist as three dimeric polypeptides (the homodimers AA and BB and the heterodimer AB). Recently, however, the PDGF C and D chains were discovered in a BLAST search of the expressed sequence tag databases. The PDGF CC and DD dimers have a unique two-domain structure with an NH2-terminal CUB (compliment subcomponents C1r/C1s, Uegf, and Bmp1) domain and a COOH-terminal PDGF/vascular endothelial growth factor domain. Whereas secreted PDGF AA, BB, and AB readily activate their cell surface receptors, it was suggested that extracellular proteolytic removal of the CUB domain is required for the PDGF/vascular endothelial growth factor domain of PDGF CC and DD to activate PDGF receptors. In the present study, we examined the processing of latent PDGF D into its active form and the effects of PDGF D expression on prostate cancer progression. We show that LNCaP cells auto-activate latent PDGF DD into the active PDGF domain, which can induce phosphorylation of the β-PDGF receptor and stimulates LNCaP cell proliferation in an autocrine manner. Additionally, LNCaP-PDGF D-conditioned medium induces migration of the prostate fibroblast cell line 1532-FTX, indicating LNCaP-processed PDGF DD is active in a paracrine manner as well. In a severe combined immunodeficient mouse model, PDGF DD expression accelerates early onset of prostate tumor growth and drastically enhances prostate carcinoma cell interaction with surrounding stromal cells. These demonstrate a potential oncogenic activity of PDGF DD in the development and/or progression of prostate cancer. PMID:14996732

  10. Epidermal Growth Factor Enhances Cellular Uptake of Polystyrene Nanoparticles by Clathrin-Mediated Endocytosis

    PubMed Central

    Phuc, Le Thi Minh; Taniguchi, Akiyoshi

    2017-01-01

    The interaction between nanoparticles and cells has been studied extensively, but most research has focused on the effect of various nanoparticle characteristics, such as size, morphology, and surface charge, on the cellular uptake of nanoparticles. In contrast, there have been very few studies to assess the influence of cellular factors, such as growth factor responses, on the cellular uptake efficiency of nanoparticles. The aim of this study was to clarify the effects of epidermal growth factor (EGF) on the uptake efficiency of polystyrene nanoparticles (PS NPs) by A431 cells, a human carcinoma epithelial cell line. The results showed that EGF enhanced the uptake efficiency of A431 cells for PS NPs. In addition, inhibition and localization studies of PS NPs and EGF receptors (EGFRs) indicated that cellular uptake of PS NPs is related to the binding of EGF–EGFR complex and PS NPs. Different pathways are used to enter the cells depending on the presence or absence of EGF. In the presence of EGF, cellular uptake of PS NPs is via clathrin-mediated endocytosis, whereas, in the absence of EGF, uptake of PS NPs does not involve clathrin-mediated endocytosis. Our findings indicate that EGF enhances cellular uptake of PS NPs by clathrin-mediated endocytosis. This result could be important for developing safe nanoparticles and their safe use in medical applications. PMID:28629179

  11. Epidermal Growth Factor Enhances Cellular Uptake of Polystyrene Nanoparticles by Clathrin-Mediated Endocytosis.

    PubMed

    Phuc, Le Thi Minh; Taniguchi, Akiyoshi

    2017-06-19

    The interaction between nanoparticles and cells has been studied extensively, but most research has focused on the effect of various nanoparticle characteristics, such as size, morphology, and surface charge, on the cellular uptake of nanoparticles. In contrast, there have been very few studies to assess the influence of cellular factors, such as growth factor responses, on the cellular uptake efficiency of nanoparticles. The aim of this study was to clarify the effects of epidermal growth factor (EGF) on the uptake efficiency of polystyrene nanoparticles (PS NPs) by A431 cells, a human carcinoma epithelial cell line. The results showed that EGF enhanced the uptake efficiency of A431 cells for PS NPs. In addition, inhibition and localization studies of PS NPs and EGF receptors (EGFRs) indicated that cellular uptake of PS NPs is related to the binding of EGF-EGFR complex and PS NPs. Different pathways are used to enter the cells depending on the presence or absence of EGF. In the presence of EGF, cellular uptake of PS NPs is via clathrin-mediated endocytosis, whereas, in the absence of EGF, uptake of PS NPs does not involve clathrin-mediated endocytosis. Our findings indicate that EGF enhances cellular uptake of PS NPs by clathrin-mediated endocytosis. This result could be important for developing safe nanoparticles and their safe use in medical applications.

  12. A glioma-derived analog to platelet-derived growth factor: demonstration of receptor competing activity and immunological crossreactivity.

    PubMed Central

    Nistér, M; Heldin, C H; Wasteson, A; Westermark, B

    1984-01-01

    A human clonal glioma cell line, U-343 MGa Cl 2, cultured under serum-free conditions, was found to release a factor that competed with 125I-labeled platelet-derived growth factor (125I-PDGF) for binding to human foreskin fibroblasts. The concentration of competing activity in conditioned medium was equal to 20-30 ng of PDGF per ml. The PDGF receptor competing activity had an elution position on Sephadex G-200 close to that of tracer PDGF. The same fractions in the chromatogram also contained growth-promoting activity and material active in a PDGF radioimmunoassay. Incubation of partially purified, 125I-labeled glioma factor with fibroblasts, or rabbit anti-PDGF serum, led to the selective binding of a component with an estimated Mr of 31,000, as shown by NaDodSO4/gel electrophoresis under nonreducing conditions. After reduction this component migrated as a Mr 18,000 protein. Thus, the behavior in NaDodSO4/gel electrophoresis was similar to that of PDGF. Furthermore, incubation of partially purified glioma factor with immobilized PDGF antibodies markedly decreased the amount of PDGF receptor competing activity remaining in the supernatant. These results suggest that the factor produced by glioma cells has structural, immunological, and functional resemblance to PDGF. We previously reported that a human osteosarcoma cell line produces a PDGF-like molecule with growth-promoting activity. Taken together with the recent finding that PDGF is homologous to the transforming gene product of simian sarcoma virus, our present data give additional support for the idea that an autocrine activation of the PDGF receptor may be operational in the growth of human tumors of mesenchymal or glial origin. Images PMID:6322178

  13. Effect of summer daylight exposure and genetic background on growth in growth hormone-deficient children.

    PubMed

    De Leonibus, C; Chatelain, P; Knight, C; Clayton, P; Stevens, A

    2016-11-01

    The response to growth hormone in humans is dependent on phenotypic, genetic and environmental factors. The present study in children with growth hormone deficiency (GHD) collected worldwide characterised gene-environment interactions on growth response to recombinant human growth hormone (r-hGH). Growth responses in children are linked to latitude, and we found that a correlate of latitude, summer daylight exposure (SDE), was a key environmental factor related to growth response to r-hGH. In turn growth response was determined by an interaction between both SDE and genes known to affect growth response to r-hGH. In addition, analysis of associated networks of gene expression implicated a role for circadian clock pathways and specifically the developmental transcription factor NANOG. This work provides the first observation of gene-environment interactions in children treated with r-hGH.

  14. Effect of summer daylight exposure and genetic background on growth in growth hormone-deficient children

    PubMed Central

    De Leonibus, C; Chatelain, P; Knight, C; Clayton, P; Stevens, A

    2016-01-01

    The response to growth hormone in humans is dependent on phenotypic, genetic and environmental factors. The present study in children with growth hormone deficiency (GHD) collected worldwide characterised gene–environment interactions on growth response to recombinant human growth hormone (r-hGH). Growth responses in children are linked to latitude, and we found that a correlate of latitude, summer daylight exposure (SDE), was a key environmental factor related to growth response to r-hGH. In turn growth response was determined by an interaction between both SDE and genes known to affect growth response to r-hGH. In addition, analysis of associated networks of gene expression implicated a role for circadian clock pathways and specifically the developmental transcription factor NANOG. This work provides the first observation of gene–environment interactions in children treated with r-hGH. PMID:26503811

  15. Extracellular Matrix and Growth Factors Improve the Efficacy of Intramuscular Islet Transplantation.

    PubMed

    Tsuchiya, Haruyuki; Sakata, Naoaki; Yoshimatsu, Gumpei; Fukase, Masahiko; Aoki, Takeshi; Ishida, Masaharu; Katayose, Yu; Egawa, Shinichi; Unno, Michiaki

    2015-01-01

    The efficacy of intramuscular islet transplantation is poor despite being technically simple, safe, and associated with reduced rates of severe complications. We evaluated the efficacy of combined treatment with extracellular matrix (ECM) and growth factors in intramuscular islet transplantation. Male BALB/C mice were used for the in vitro and transplantation studies. The following three groups were evaluated: islets without treatment (islets-only group), islets embedded in ECM with growth factors (Matrigel group), and islets embedded in ECM without growth factors [growth factor-reduced (GFR) Matrigel group]. The viability and insulin-releasing function of islets cultured for 96 h were significantly improved in Matrigel and GFR Matrigel groups compared with the islets-only group. Blood glucose and serum insulin levels immediately following transplantation were significantly improved in the Matrigel and GFR Matrigel groups and remained significantly improved in the Matrigel group at postoperative day (POD) 28. On histological examination, significantly decreased numbers of TdT-mediated deoxyuridine triphosphate-biotin nick end labeling-positive islet cells and significantly increased numbers of Ki67-positive cells were observed in the Matrigel and GFR Matrigel groups at POD 3. Peri-islet revascularization was most prominent in the Matrigel group at POD 14. The efficacy of intramuscular islet transplantation was improved by combination treatment with ECM and growth factors through the inhibition of apoptosis, increased proliferation of islet cells, and promotion of revascularization.

  16. Mechanisms of integrin-vascular endothelial growth factor receptor cross-activation in angiogenesis.

    PubMed

    Mahabeleshwar, Ganapati H; Feng, Weiyi; Reddy, Kumar; Plow, Edward F; Byzova, Tatiana V

    2007-09-14

    The functional responses of endothelial cells are dependent on signaling from peptide growth factors and the cellular adhesion receptors, integrins. These include cell adhesion, migration, and proliferation, which, in turn, are essential for more complex processes such as formation of the endothelial tube network during angiogenesis. This study identifies the molecular requirements for the cross-activation between beta3 integrin and tyrosine kinase receptor 2 for vascular endothelial growth factor (VEGF) receptor (VEGFR-2) on endothelium. The relationship between VEGFR-2 and beta3 integrin appears to be synergistic, because VEGFR-2 activation induces beta3 integrin tyrosine phosphorylation, which, in turn, is crucial for VEGF-induced tyrosine phosphorylation of VEGFR-2. We demonstrate here that adhesion- and growth factor-induced beta3 integrin tyrosine phosphorylation are directly mediated by c-Src. VEGF-stimulated recruitment and activation of c-Src and subsequent beta3 integrin tyrosine phosphorylation are critical for interaction between VEGFR-2 and beta3 integrin. Moreover, c-Src mediates growth factor-induced beta3 integrin activation, ligand binding, beta3 integrin-dependent cell adhesion, directional migration of endothelial cells, and initiation of angiogenic programming in endothelial cells. Thus, the present study determines the molecular mechanisms and consequences of the synergism between 2 cell surface receptor systems, growth factor receptor and integrins, and opens new avenues for the development of pro- and antiangiogenic strategies.

  17. Tissue Engineering Using Transfected Growth-Factor Genes

    NASA Technical Reports Server (NTRS)

    Madry, Henning; Langer, Robert S.; Freed, Lisa E.; Trippel, Stephen; Vunjak-Novakovic, Gordana

    2005-01-01

    A method of growing bioengineered tissues includes, as a major component, the use of mammalian cells that have been transfected with genes for secretion of regulator and growth-factor substances. In a typical application, one either seeds the cells onto an artificial matrix made of a synthetic or natural biocompatible material, or else one cultures the cells until they secrete a desired amount of an extracellular matrix. If such a bioengineered tissue construct is to be used for surgical replacement of injured tissue, then the cells should preferably be the patient s own cells or, if not, at least cells matched to the patient s cells according to a human-leucocyteantigen (HLA) test. The bioengineered tissue construct is typically implanted in the patient's injured natural tissue, wherein the growth-factor genes enhance metabolic functions that promote the in vitro development of functional tissue constructs and their integration with native tissues. If the matrix is biodegradable, then one of the results of metabolism could be absorption of the matrix and replacement of the matrix with tissue formed at least partly by the transfected cells. The method was developed for articular chondrocytes but can (at least in principle) be extended to a variety of cell types and biocompatible matrix materials, including ones that have been exploited in prior tissue-engineering methods. Examples of cell types include chondrocytes, hepatocytes, islet cells, nerve cells, muscle cells, other organ cells, bone- and cartilage-forming cells, epithelial and endothelial cells, connective- tissue stem cells, mesodermal stem cells, and cells of the liver and the pancreas. Cells can be obtained from cell-line cultures, biopsies, and tissue banks. Genes, molecules, or nucleic acids that secrete factors that influence the growth of cells, the production of extracellular matrix material, and other cell functions can be inserted in cells by any of a variety of standard transfection techniques.

  18. [Growth Factors and Interleukins in Amniotic Membrane Tissue Homogenate].

    PubMed

    Stachon, T; Bischoff, M; Seitz, B; Huber, M; Zawada, M; Langenbucher, A; Szentmáry, N

    2015-07-01

    Application of amniotic membrane homogenate eye drops may be a potential treatment alternative for therapy resistant corneal epithelial defects. The purpose of this study was to determine the concentrations of epidermal growth factor (EGF), fibroblast growth factor basic (bFGF), hepatocyte growth factor (HGF), keratinocyte growth factor (KGF), interleukin-6 (IL-6) and interleukin-8 (IL-8) in amniotic membrane homogenates. Amniotic membranes of 8 placentas were prepared and thereafter stored at - 80 °C using the standard methods of the LIONS Cornea Bank Saar-Lor-Lux, Trier/Westpfalz. Following defreezing, amniotic membranes were cut in two pieces and homogenized in liquid nitrogen. One part of the homogenate was prepared in cell-lysis buffer, the other part was prepared in PBS. The tissue homogenates were stored at - 20 °C until enzyme-linked immunosorbent assay (ELISA) analysis for EGF, bFGF, HGF, KGF, IL-6 and IL-8 concentrations. Concentrations of KGF, IL-6 and IL-8 were below the detection limit using both preparation techniques. The EGF concentration in tissue homogenates treated with cell-lysis buffer (2412 pg/g tissue) was not significantly different compared to that of tissue homogenates treated with PBS (1586 pg/g tissue, p = 0.72). bFGF release was also not significantly different using cell-lysis buffer (3606 pg/g tissue) or PBS treated tissue homogenates (4649 pg/g tissue, p = 0.35). HGF release was significantly lower using cell-lysis buffer (23,555 pg/g tissue), compared to PBS treated tissue (47,766 pg/g tissue, p = 0.007). Containing EGF, bFGF and HGF, and lacking IL-6 and IL-8, the application of amniotic membrane homogenate eye drops may be a potential treatment alternative for therapy-resistant corneal epithelial defects. Georg Thieme Verlag KG Stuttgart · New York.

  19. Rapid Method of Determining Factors Limiting Bacterial Growth in Soil

    PubMed Central

    Aldén, L.; Demoling, F.; Bååth, E.

    2001-01-01

    A technique to determine which nutrients limit bacterial growth in soil was developed. The method was based on measuring the thymidine incorporation rate of bacteria after the addition of C, N, and P in different combinations to soil samples. First, the thymidine incorporation method was tested in two different soils: an agricultural soil and a forest humus soil. Carbon (as glucose) was found to be the limiting substance for bacterial growth in both of these soils. The effect of adding different amounts of nutrients was studied, and tests were performed to determine whether the additions affected the soil pH and subsequent bacterial activity. The incubation time required to detect bacterial growth after adding substrate to the soil was also evaluated. Second, the method was used in experiments in which three different size fractions of straw (1 to 2, 0.25 to 1, and <0.25 mm) were mixed into the agricultural soil in order to induce N limitation for bacterial growth. When the straw fraction was small enough (<0.25 mm), N became the limiting nutrient for bacterial growth after about 3 weeks. After the addition of the larger straw fractions (1 to 2 and 0.25 to 1 mm), the soil bacteria were C limited throughout the incubation period (10 weeks), although an increase in the thymidine incorporation rate after the addition of C and N together compared with adding them separately was seen in the sample containing the size fraction from 0.25 to 1 mm. Third, soils from high-pH, limestone-rich areas were examined. P limitation was observed in one of these soils, while tendencies toward P limitation were seen in some of the other soils. PMID:11282640

  20. Transforming Growth Factor-β1 T869C Gene Polymorphism Is Associated with Acquired Sick Sinus Syndrome via Linking a Higher Serum Protein Level

    PubMed Central

    Chen, Jan-Yow; Liu, Jiung-Hsiun; Wu, Hong-Dar Isaac; Lin, Kuo-Hung; Chang, Kuan-Cheng; Liou, Ying-Ming

    2016-01-01

    Background Familial sick sinus syndrome is associated with gene mutations and dysfunction of ion channels. In contrast, degenerative fibrosis of the sinus node tissue plays an important role in the pathogenesis of acquired sick sinus syndrome. There is a close relationship between transforming growth factor-β1 mediated cardiac fibrosis and acquired arrhythmia. It is of interest to examine whether transforming growth factor-β1 is involved in the pathogenesis of acquired sick sinus syndrome. Methods Overall, 110 patients with acquired SSS and 137 age/gender-matched controls were screened for transforming growth factor-β1 and cardiac sodium channel gene polymorphisms using gene sequencing or restriction fragment length polymorphism methods. An enzyme-linked immunosorbent assay was used to determine the serum level of transforming growth factor-β1. Results Two transforming growth factor-β1 gene polymorphisms (C-509T and T+869C) and one cardiac sodium channel gene polymorphism (H588R) have been identified. The C-dominant CC/CT genotype frequency of T869C was significantly higher in acquired sick sinus syndrome patients than in controls (OR 2.09, 95% CI 1.16–3.75, P = 0.01). Consistently, the level of serum transforming growth factor-β1 was also significantly greater in acquired sick sinus syndrome group than in controls (5.3±3.4 ng/ml vs. 3.7±2.4 ng/ml, P = 0.01). In addition, the CC/CT genotypes showed a higher transforming growth factor-β1 serum level than the TT genotype (4.25 ± 2.50 ng/ml vs. 2.71± 1.76 ng/ml, P = 0.028) in controls. Conclusion Transforming growth factor-β1 T869C polymorphism, correlated with high serum transforming growth factor-β1 levels, is associated with susceptibility to acquired sick sinus syndrome. PMID:27380173

  1. Understanding the role of growth factors in embryonic development: insights from the lens

    PubMed Central

    Lovicu, F. J.; McAvoy, J. W.; de Iongh, R. U.

    2011-01-01

    Growth factors play key roles in influencing cell fate and behaviour during development. The epithelial cells and fibre cells that arise from the lens vesicle during lens morphogenesis are bathed by aqueous and vitreous, respectively. Vitreous has been shown to generate a high level of fibroblast growth factor (FGF) signalling that is required for secondary lens fibre differentiation. However, studies also show that FGF signalling is not sufficient and roles have been identified for transforming growth factor-β and Wnt/Frizzled families in regulating aspects of fibre differentiation. In the case of the epithelium, key roles for Wnt/β-catenin and Notch signalling have been demonstrated in embryonic development, but it is not known if other factors are required for its formation and maintenance. This review provides an overview of current knowledge about growth factor regulation of differentiation and maintenance of lens cells. It also highlights areas that warrant future study. PMID:21402581

  2. A nanoparticulate injectable hydrogel as a tissue engineering scaffold for multiple growth factor delivery for bone regeneration.

    PubMed

    Dyondi, Deepti; Webster, Thomas J; Banerjee, Rinti

    2013-01-01

    Gellan xanthan gels have been shown to be excellent carriers for growth factors and as matrices for several tissue engineering applications. Gellan xanthan gels along with chitosan nanoparticles of 297 ± 61 nm diameter, basic fibroblast growth factor (bFGF), and bone morphogenetic protein 7 (BMP7) were employed in a dual growth factor delivery system to promote the differentiation of human fetal osteoblasts. An injectable system with ionic and temperature gelation was optimized and characterized. The nanoparticle loaded gels showed significantly improved cell proliferation and differentiation due to the sustained release of growth factors. A differentiation marker study was conducted, analyzed, and compared to understand the effect of single vs dual growth factors and free vs encapsulated growth factors. Dual growth factor loaded gels showed a higher alkaline phosphatase and calcium deposition compared to single growth factor loaded gels. The results suggest that encapsulation and stabilization of growth factors within nanoparticles and gels are promising for bone regeneration. Gellan xanthan gels also showed antibacterial effects against Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis, the common pathogens in implant failure.

  3. Effects of transforming growth factor-alpha (TGF-alpha) in vitro and in vivo on reovirus replication.

    PubMed

    Organ, Edward L; Nalbantyan, Christopher D; Nanney, Lillian B; Woodward, Stephen C; Sheng, Jinsong; Dubois, Raymond N; Price, James; Sutcliffe, Marilyn; Coffey, Robert J; Rubin, Donald H

    2004-07-01

    We have utilized growth factors in in vitro and in vivo systems to examine the role of cellular proliferation in reovirus replication. In vitro, proliferating RIE-1 cells can be infected with whole reovirus virions, but are relatively resistant to infection once confluent (Go arrest). It has been shown that TGF-alpha, which signals through the EGF-receptor (EGF-R), is capable of dramatically increasing the number of RIE-1 cells entering the S-phase in the presence of additional serum factors. Stimulation of the EGF-R without serum results in minimal increases in cells entering the S-phase with a restriction in reovirus replication. Therefore, other factors in serum are essential for fully permissive infection. In vivo, we used metallothionein (MT) promoter/enhancer-TGF-alpha transgenic mice to study the effect of cytokine activation on reovirus type 1 infection. Virus replication decreased following oral infection in these transgenic mice at 1 month of age, concordant with increased mucin production. Titers of reovirus obtained from the livers of 1 year old transgenic mice were approximately 10-fold higher than titers obtained in control mice. Taken together, these data indicate that while growth factor activation ultimately leads to an increase in virus infectivity, other factors may be necessary for reovirus replication.

  4. The Protective Effects of Exclusive Enteral Nutrition Formulas on Growth Factor Expression and the Proximal Tibial Epiphyseal Growth Plate in a TNBS-Induced IBD Rat Model.

    PubMed

    Shi, Jieru; Huang, Zhiheng; Wang, Yuhuan; Huang, Ying

    2015-07-01

    This study aimed to evaluate the effectiveness of different types of nutritional formulas in a rat model of TNBS-induced IBD. IBD was induced with TNBS in 4-week-old rats that were then fed different exclusive enteral nutrition diets for 7 days. The length of the tibia and the number of chondrocytes in the proximal tibias were analyzed at 7 days after supplementation. Immunohistochemical analysis, ELISA and real-time PCR were performed to evaluate the levels of growth hormone receptor (GHR) and insulin-like growth factor-I receptor (IGF-IR), the growth factors IGF-I and insulin-like growth factor-binding protein-3 (IGFBP3) , bone morphogenetic protein (BMP)-2 and BMP-6 respectively. The results demonstrated that the tibia length of the peptide formula group was longer than that of the IBD-Modulen(®) formula and normal diet groups (P < 0.05). Furthermore, the number of chondrocytes of the proximal tibial was more pronounced in the peptide formula group compared to the other groups (P < 0.05). The peptide formula was also more effective in increasing the expression of GHR compared to the other groups (P < 0.05), while the expression of IGF-IR was not significantly different (P > 0.05). In addition, the IGF-I and IGFBP3 levels were more pronounced in the peptide formula supplement group (P < 0.05), and the expression of BMP-2 and BMP-6 mRNA in the proximal tibia growth plate from the peptide formula group was higher than that in the ordinary formula and normal diet groups (P < 0.05). EEN, and particularly a peptide formula, exerted protective effects on the proximal tibial epiphyseal growth plate in a TNBS-induced IBD model.

  5. Discerning environmental factors affecting current tree growth in Central Europe.

    PubMed

    Cienciala, Emil; Russ, Radek; Šantrůčková, Hana; Altman, Jan; Kopáček, Jiří; Hůnová, Iva; Štěpánek, Petr; Oulehle, Filip; Tumajer, Jan; Ståhl, Göran

    2016-12-15

    We examined the effect of individual environmental factors on the current spruce tree growth assessed from a repeated country-level statistical landscape (incl. forest) survey in the Czech Republic. An extensive set of variables related to tree size, competition, site characteristics including soil texture, chemistry, N deposition and climate was tested within a random-effect model to explain growth in the conditions of dominantly managed forest ecosystems. The current spruce basal area increment was assessed from two consecutive landscape surveys conducted in 2008/2009 and six years later in 2014/2015. Tree size, age and competition within forest stands were found to be the dominant explanatory variables, whereas the expression of site characteristics, environmental and climatic drives was weaker. The significant site variables affecting growth included soil C/N ratio and soil exchangeable acidity (pH KCl; positive response) reflecting soil chemistry, long-term N-deposition (averaged since 1975) in combination with soil texture (clay content) and Standardized Precipitation Index (SPI), a drought index expressing moisture conditions. Sensitivity of growth to N-deposition was positive, although weak. SPI was positively related to and significant in explaining tree growth when expressed for the growth season. Except SPI, no significant relation of growth was determined to altitude-related variables (temperature, growth season length). We identified the current spruce growth optimum at elevations about 800ma.s.l. or higher in the conditions of the country. This suggests that at lower elevations, limitation by a more pronounced water deficit dominates, whereas direct temperature limitation may concern the less frequent higher elevations. The mixed linear model of spruce tree growth explained 55 and 65% of the variability with fixed and random effects included, respectively, and provided new insights on the current spruce tree growth and factors affecting it within the

  6. Expression, purification, and characterization of recombinant human and murine milk fat globule-epidermal growth factor-factor 8.

    PubMed

    Castellanos, Erick R; Ciferri, Claudio; Phung, Wilson; Sandoval, Wendy; Matsumoto, Marissa L

    2016-08-01

    Milk fat globule-epidermal growth factor-factor 8 (MFG-E8), as its name suggests, is a major glycoprotein component of milk fat globules secreted by the mammary epithelium. Although its role in milk fat production is unclear, MFG-E8 has been shown to act as a bridge linking apoptotic cells to phagocytes for removal of these dying cells. MFG-E8 is capable of bridging these two very different cell types via interactions through both its epidermal growth factor (EGF)-like domain(s) and its lectin-type C domains. The EGF-like domain interacts with αVβ3 and αVβ5 integrins on the surface of phagocytes, whereas the C domains bind phosphatidylserine found on the surface of apoptotic cells. In an attempt to purify full-length, recombinant MFG-E8 expressed in either insect cells or CHO cells, we find that it is highly aggregated. Systematic truncation of the domain architecture of MFG-E8 indicates that the C domains are mainly responsible for the aggregation propensity. Addition of Triton X-100 to the conditioned cell culture media allowed partial recovery of non-aggregated, full-length MFG-E8. A more comprehensive detergent screen identified CHAPS as a stabilizer of MFG-E8 and allowed purification of a significant portion of non-aggregated, full-length protein. The CHAPS-stabilized recombinant MFG-E8 retained its natural ability to bind both αVβ3 and αVβ5 integrins and phosphatidylserine suggesting that it is properly folded and active. Herein we describe an efficient purification method for production of non-aggregated, full-length MFG-E8. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Purification and Refolding of Overexpressed Human Basic Fibroblast Growth Factor in Escherichia coli

    PubMed Central

    Alibolandi, Mona; Mirzahoseini, Hasan

    2011-01-01

    This work describes the integration of expanded bed adsorption (EBA) and adsorptive protein refolding operations used to recover purified and biologically active human basic fibroblast growth factor from inclusion bodies expressed in E. coli. Insoluble overexpressed human basic fibroblast growth factor has been purified on CM Hyper Z matrix by expanded bed adsorption after isolation and solubilization in 8 M urea. The adsorption was made in expanded bed without clarification steps such as centrifugation. Column refolding was done by elimination of urea and elution with NaCl. The human basic fibroblast growth factor was obtained as a highly purified soluble monomer form with similar behavior in circular dichroism and fluorescence spectroscopy as native protein. A total of 92.52% of the available human basic fibroblast growth factor was recovered as biologically active and purified protein using the mentioned purification and refolding process. This resulted in the first procedure describing high-throughput purification and refolding of human basic fibroblast growth factor in one step and is likely to have the greatest benefit for proteins that tend to aggregate when refolded by dilution. PMID:21837279

  8. Placental growth factor expression is reversed by antivascular endothelial growth factor therapy under hypoxic conditions.

    PubMed

    Zhou, Ai-Yi; Bai, Yu-Jing; Zhao, Min; Yu, Wen-Zhen; Huang, Lv-Zhen; Li, Xiao-Xin

    2014-08-01

    Clinical trials have revealed that the antivascular endothelial growth factor (VEGF) therapies are effective in retinopathy of prematurity (ROP). But the low level of VEGF was necessary as a survival signal in healthy conditions, and endogenous placental growth factor (PIGF) is redundant for development. The purpose of this study was to elucidate the PIGF expression under hypoxia as well as the influence of anti-VEGF therapy on PIGF. CoCl2-induced hypoxic human umbilical vein endothelial cells (HUVECs) were used for an in vitro study, and oxygen-induced retinopathy (OIR) mice models were used for an in vivo study. The expression patterns of PIGF under hypoxic conditions and the influence of anti-VEGF therapy on PIGF were evaluated by quantitative reverse transcription-polymerase chain reaction (RTPCR). The retinal avascular areas and neovascularization (NV) areas of anti-VEGF, anti-PIGF and combination treatments were calculated. Retina PIGF concentration was evaluated by ELISA after treatment. The vasoactive effects of exogenous PIGF on HUVECs were investigated by proliferation and migration studies. PIGF mRNA expression was reduced by hypoxia in OIR mice, in HUVECs under hypoxia and anti-VEGF treatment. However, PIGF expression was reversed by anti-VEGF therapy in the OIR model and in HUVECs under hypoxia. Exogenous PIGF significantly inhibited HUVECs proliferation and migration under normal conditions, but it stimulated cell proliferation and migration under hypoxia. Anti-PIGF treatment was effective for neovascular tufts in OIR mice (P<0.05). The finding that PIGF expression is iatrogenically up-regulated by anti-VEGF therapy provides a consideration to combine it with anti-PIGF therapy.

  9. A Prodomain Fragment from the Proteolytic Activation of Growth Differentiation Factor 11 Remains Associated with the Mature Growth Factor and Keeps It Soluble.

    PubMed

    Pepinsky, Blake; Gong, Bang-Jian; Gao, Yan; Lehmann, Andreas; Ferrant, Janine; Amatucci, Joseph; Sun, Yaping; Bush, Martin; Walz, Thomas; Pederson, Nels; Cameron, Thomas; Wen, Dingyi

    2017-08-22

    Growth differentiation factor 11 (GDF11), a member of the transforming growth factor β (TGF-β) family, plays diverse roles in mammalian development. It is synthesized as a large, inactive precursor protein containing a prodomain, pro-GDF11, and exists as a homodimer. Activation requires two proteolytic processing steps that release the prodomains and transform latent pro-GDF11 into active mature GDF11. In studying proteolytic activation in vitro, we discovered that a 6-kDa prodomain peptide containing residues 60-114, PDP 60-114 , remained associated with the mature growth factor. Whereas the full-length prodomain of GDF11 is a functional antagonist, PDP 60-114 had no impact on activity. The specific activity of the GDF11/PDP 60-114 complex (EC 50 = 1 nM) in a SMAD2/3 reporter assay was identical to that of mature GDF11 alone. PDP 60-114 improved the solubility of mature GDF11 at neutral pH. As the growth factor normally aggregates/precipitates at neutral pH, PDP 60-114 can be used as a solubility-enhancing formulation. Expression of two engineered constructs with PDP 60-114 genetically fused to the mature domain of GDF11 through a 2x or 3x G4S linker produced soluble monomeric products that could be dimerized through redox reactions. The construct with a 3x G4S linker retained 10% activity (EC 50 = 10 nM), whereas the construct connected with a 2x G4S linker could only be activated (EC 50 = 2 nM) by protease treatment. Complex formation with PDP 60-114 represents a new strategy for stabilizing GDF11 in an active state that may translate to other members of the TGF-β family that form latent pro/mature domain complexes.

  10. Endothelial Heparan Sulfate 6-O-Sulfation Levels Regulate Angiogenic Responses of Endothelial Cells to Fibroblast Growth Factor 2 and Vascular Endothelial Growth Factor*

    PubMed Central

    Ferreras, Cristina; Rushton, Graham; Cole, Claire L.; Babur, Muhammad; Telfer, Brian A.; van Kuppevelt, Toin H.; Gardiner, John M.; Williams, Kaye J.; Jayson, Gordon C.; Avizienyte, Egle

    2012-01-01

    Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor 165 (VEGF165) are potent pro-angiogenic growth factors that play a pivotal role in tumor angiogenesis. The activity of these growth factors is regulated by heparan sulfate (HS), which is essential for the formation of FGF2/FGF receptor (FGFR) and VEGF165/VEGF receptor signaling complexes. However, the structural characteristics of HS that determine activation or inhibition of such complexes are only partially defined. Here we show that ovarian tumor endothelium displays high levels of HS sequences that harbor glucosamine 6-O-sulfates when compared with normal ovarian vasculature where these sequences are also detected in perivascular area. Reduced HS 6-O-sulfotransferase 1 (HS6ST-1) or 6-O-sulfotransferase 2 (HS6ST-2) expression in endothelial cells impacts upon the prevalence of HS 6-O-sulfate moieties in HS sequences, which consist of repeating short, highly sulfated S domains interspersed by transitional N-acetylated/N-sulfated domains. 1–40% reduction in 6-O-sulfates significantly compromises FGF2- and VEGF165-induced endothelial cell sprouting and tube formation in vitro and FGF2-dependent angiogenesis in vivo. Moreover, HS on wild-type neighboring endothelial or smooth muscle cells fails to restore endothelial cell sprouting and tube formation. The affinity of FGF2 for HS with reduced 6-O-sulfation is preserved, although FGFR1 activation is inhibited correlating with reduced receptor internalization. These data show that 6-O-sulfate moieties in endothelial HS are of major importance in regulating FGF2- and VEGF165-dependent endothelial cell functions in vitro and in vivo and highlight HS6ST-1 and HS6ST-2 as potential targets of novel antiangiogenic agents. PMID:22927437

  11. Heparin-binding growth factor isolated from human prostatic extracts.

    PubMed

    Mydlo, J H; Bulbul, M A; Richon, V M; Heston, W D; Fair, W R

    1988-01-01

    Prostatic tissue extracts from patients with benign prostatic hyperplasia (BPH) and prostatic carcinoma were fractionated using heparin-Sepharose chromatography. The mitogenic activity of eluted fractions on quiescent subconfluent Swiss Albino 3T3 fibroblasts was tested employing a tritiated-thymidine-incorporation assay. Two peaks of activity were consistently noted--one in the void volume and a second fraction which eluted with 1.3-1.6 M NaCl and contained the majority of the mitogenic activity. Both non-heparin- and heparin-binding fractions increased tritiated incorporation into a mouse osteoblast cell line (MC3T3), while only the heparin-binding fractions stimulated a human umbilical vein endothelial cell line (HUV). No increased uptake of thymidine was seen using a human prostatic carcinoma cell line (PC-3). Sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE) of lyophilized active fractions showed a persistent band at 17,500 daltons. The purified protein demonstrated angiogenic properties using the chick embryo chorioallantoic membrane (CAM) assay. Western blot analysis using antibodies specific to basic fibroblast growth factor (bFGF) or acidic FGF (aFGF) demonstrated that the former, but not the latter, bound to prostatic growth factor (PrGF), and inhibited its mitogenic activity as well. It appears that PrGF shares homology with basic fibroblast growth factors.

  12. A review of the influence of growth factors and cytokines in in vitro human keratinocyte migration.

    PubMed

    Peplow, Philip V; Chatterjee, Marissa P

    2013-04-01

    Keratinocyte migration from the wound edge is a crucial step in the reepithelization of cutaneous wounds. Growth factors and cytokines, released from cells that invade the wound matrix, play an important role, and several in vitro assays have been performed to elucidate this. The purposes of this study were to review in vitro human studies on keratinocyte migration to identify those growth factors or cytokines that stimulate keratinocyte migration and whether these assays might serve as a screening procedure prior to testing combinations of growth factors or cytokines to promote wound closure in vivo. Research papers investigating effect of growth factors and cytokines on human keratinocyte migration in vitro were retrieved from library sources, PubMed databases, reference lists of papers, and searches of relevant journals. Fourteen different growth factors and cytokines enhanced migration in scratch wound assay and HGF together with TGF-β, and IGF-1 with EGF, were more stimulatory than either growth factor alone. HGF with TGF-β1 had a greater chemokinetic effect than either growth factor alone in transmigration assay. TGF-β1, FGF-7, FGF-2 and AGF were chemotactic to keratinocytes. EGF, TGF-α, IL-1α, IGF and MGSA enhanced cell migration on ECM proteins. Many growth factors and cytokines enhanced migration of keratinocytes in vitro, and certain combinations of growth factors were more stimulatory than either alone. These and other combinations that stimulate keratinocyte migration in vitro should be tested for effect on wound closure and repair in vivo. The scratch wound assay provides a useful, inexpensive and easy-to-perform screening method for testing individual or combinations of growth factors or cytokines, or growth factors combined with other modalities such as laser irradiation, prior to performing wound healing studies with laboratory animals. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Fibroblast growth factor 8 is expressed at higher levels in lactating human breast and in breast cancer.

    PubMed

    Zammit, C; Coope, R; Gomm, J J; Shousha, S; Johnston, C L; Coombes, R C

    2002-04-08

    Fibroblast growth factor 8 can transform NIH3T3 cells and its expression has been found to be associated with breast and prostate cancer. Following our finding that fibroblast growth factor 8 mRNA expression is increased in breast cancer, we have undertaken an immunohistochemistry study of fibroblast growth factor 8 expression in a series of human breast tissues and other normal tissues. Our findings confirm increased expression of fibroblast growth factor 8 in malignant breast tissue but also show significant fibroblast growth factor 8 expression in non-malignant breast epithelial cells. No significant difference in fibroblast growth factor 8 expression was found between different grades of ductal carcinoma, lobular carcinoma and ductal carcinoma in-situ or cancer of different oestrogen receptor, progesterone receptor or nodal status. The highest levels of fibroblast growth factor 8 expression were found in lactating breast tissues and fibroblast growth factor 8 was also detected in human milk. A survey of other normal tissues showed that fibroblast growth factor 8 is expressed in the proliferative cells of the dermis and epithelial cells in colon, ovary fallopian tube and uterus. Fibroblast growth factor 8 appears to be expressed in several organs in man and appears to have an importance in lactation.

  14. New extracellular factors in glioblastoma multiforme development: neurotensin, growth differentiation factor-15, sphingosine-1-phosphate and cytomegalovirus infection

    PubMed Central

    Korbecki, Jan; Gutowska, Izabela; Kojder, Ireneusz; Jeżewski, Dariusz; Goschorska, Marta; Łukomska, Agnieszka; Lubkowska, Anna; Chlubek, Dariusz; Baranowska-Bosiacka, Irena

    2018-01-01

    Recent years have seen considerable progress in understanding the biochemistry of cancer. For example, more significance is now assigned to the tumor microenvironment, especially with regard to intercellular signaling in the tumor niche which depends on many factors secreted by tumor cells. In addition, great progress has been made in understanding the influence of factors such as neurotensin, growth differentiation factor-15 (GDF-15), sphingosine-1-phosphate (S1P), and infection with cytomegalovirus (CMV) on the ‘hallmarks of cancer’ in glioblastoma multiforme. Therefore, in the present work we describe the influence of these factors on the proliferation and apoptosis of neoplastic cells, cancer stem cells, angiogenesis, migration and invasion, and cancer immune evasion in a glioblastoma multiforme tumor. In particular, we discuss the effect of neurotensin, GDF-15, S1P (including the drug FTY720), and infection with CMV on tumor-associated macrophages (TAM), microglial cells, neutrophil and regulatory T cells (Treg), on the tumor microenvironment. In order to better understand the role of the aforementioned factors in tumoral processes, we outline the latest models of intratumoral heterogeneity in glioblastoma multiforme. Based on the most recent reports, we discuss the problems of multi-drug therapy in treating glioblastoma multiforme. PMID:29467963

  15. Extracellular matrix and growth factor engineering for controlled angiogenesis in regenerative medicine

    DOE PAGES

    Martino, Mikael M.; Brkic, Sime; Bovo, Emmanuela; ...

    2015-04-01

    In this study, blood vessel growth plays a key role in regenerative medicine, both to restore blood supply to ischemic tissues and to ensure rapid vascularization of clinical-size tissue-engineered grafts. For example, vascular endothelial growth factor (VEGF) is the master regulator of physiological blood vessel growth and is one of the main molecular targets of therapeutic angiogenesis approaches. However, angiogenesis is a complex process and there is a need to develop rational therapeutic strategies based on a firm understanding of basic vascular biology principles, as evidenced by the disappointing results of initial clinical trials of angiogenic factor delivery. In particular,more » the spatial localization of angiogenic signals in the extracellular matrix (ECM) is crucial to ensure the proper assembly and maturation of new vascular structures. Here, we discuss the therapeutic implications of matrix interactions of angiogenic factors, with a special emphasis on VEGF, as well as provide an overview of current approaches, based on protein and biomaterial engineering that mimic the regulatory functions of ECM to optimize the signaling microenvironment of vascular growth factors.« less

  16. Extracellular matrix and growth factor engineering for controlled angiogenesis in regenerative medicine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Martino, Mikael M.; Brkic, Sime; Bovo, Emmanuela

    In this study, blood vessel growth plays a key role in regenerative medicine, both to restore blood supply to ischemic tissues and to ensure rapid vascularization of clinical-size tissue-engineered grafts. For example, vascular endothelial growth factor (VEGF) is the master regulator of physiological blood vessel growth and is one of the main molecular targets of therapeutic angiogenesis approaches. However, angiogenesis is a complex process and there is a need to develop rational therapeutic strategies based on a firm understanding of basic vascular biology principles, as evidenced by the disappointing results of initial clinical trials of angiogenic factor delivery. In particular,more » the spatial localization of angiogenic signals in the extracellular matrix (ECM) is crucial to ensure the proper assembly and maturation of new vascular structures. Here, we discuss the therapeutic implications of matrix interactions of angiogenic factors, with a special emphasis on VEGF, as well as provide an overview of current approaches, based on protein and biomaterial engineering that mimic the regulatory functions of ECM to optimize the signaling microenvironment of vascular growth factors.« less

  17. Extracellular matrix and growth factor engineering for controlled angiogenesis in regenerative medicine.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Martino, Mikael M.; Brkic, Sime; Bovo, Emmanuela

    Blood vessel growth plays a key role in regenerative medicine, both to restore blood supply to ischemic tissues and to ensure rapid vascularization of clinical-size tissue-engineered grafts. For example, vascular endothelial growth factor (VEGF) is the master regulator of physiological blood vessel growth and is one of the main molecular targets of therapeutic angiogenesis approaches. However, angiogenesis is a complex process and there is a need to develop rational therapeutic strategies based on a firm understanding of basic vascular biology principles, as evidenced by the disappointing results of initial clinical trials of angiogenic factor delivery. In particular, the spatial localizationmore » of angiogenic signals in the extracellular matrix (ECM) is crucial to ensure the proper assembly and maturation of new vascular structures. Here, we discuss the therapeutic implications of matrix interactions of angiogenic factors, with a special emphasis on VEGF, as well as provide an overview of current approaches, based on protein and biomaterial engineering that mimic the regulatory functions of ECM to optimize the signaling microenvironment of vascular growth factors.« less

  18. A highly versatile adaptor protein for the tethering of growth factors to gelatin-based biomaterials.

    PubMed

    Addi, Cyril; Murschel, Frédéric; Liberelle, Benoît; Riahi, Nesrine; De Crescenzo, Gregory

    2017-03-01

    In the field of tissue engineering, the tethering of growth factors to tissue scaffolds in an oriented manner can enhance their activity and increase their half-life. We chose to investigate the capture of the basic Fibroblast Growth Factor (bFGF) and the Epidermal Growth Factor (EGF) on a gelatin layer, as a model for the functionalization of collagen-based biomaterials. Our strategy relies on the use of two high affinity interactions, that is, the one between two distinct coil peptides as well as the one occurring between a collagen-binding domain (CBD) and gelatin. We expressed a chimeric protein to be used as an adaptor that comprises one of the coil peptides and a CBD derived from the human fibronectin. We proved that it has the ability to bind simultaneously to a gelatin substrate and to form a heterodimeric coiled-coil domain with recombinant growth factors being tagged with the complementary coil peptide. The tethering of the growth factors was characterized by ELISA and surface plasmon resonance-based biosensing. The bioactivity of the immobilized bFGF and EGF was evaluated by a human umbilical vein endothelial cell proliferation assay and a vascular smooth muscle cell survival assay. We found that the tethering of EGF preserved its mitogenic and anti-apoptotic activity. In the case of bFGF, when captured via our adaptor protein, changes in its natural mode of interaction with gelatin were observed. In an effort to functionalize collagen/gelatin-based biomaterials with growth factors, we have designed an adaptor protein corresponding to a collagen-binding domain fused to a coil peptide. In our strategy, this adaptor protein captures growth factors being tagged with the partner coil peptide in a specific, stable and oriented manner. We have found that the tethering of the Epidermal Growth Factor preserved its mitogenic and anti-apoptotic activity. In the case of the basic Fibroblast Growth Factor, the captured growth factor remained bioactive although its

  19. Newfound compassion after prostate cancer: a psychometric evaluation of additional items in the Posttraumatic Growth Inventory.

    PubMed

    Morris, Bronwyn A; Wilson, Bridget; Chambers, Suzanne K

    2013-12-01

    The most widely used measure of posttraumatic growth (PTG) is the Posttraumatic Growth Inventory (PTGI). Qualitative research indicates the importance of increased compassion as a result of struggling with challenges presented by cancer and treatments. However, current PTG measures may not adequately assess compassion. A cross-sectional survey of 514 prostate cancer survivors assessed the PTGI and Dispositional Positive Emotional Scale (DPES). Five additional PTG items were derived from previous qualitative research to assess increased compassion. After removing eight items with complex loadings, a principal components analysis with oblimin rotation revealed a six-component structure. A clear delineation was seen between components relating to compassion, new possibilities, relating to others, personal strength, appreciation of life and spiritual change. Compassion accounted for 48.9 % of variance in data, with the overall model accounting for 79.9 % of variance. Strong factorability was demonstrated through Kaiser-Meyer-Olkin (0.92) and Bartlett's test of sphericity (approximate χ (2) = 5,791.85, df 153, p < 0.001). The six-component structure was validated with a confirmatory factor analysis. Strong internal consistency was evidenced through Cronbach's alpha coefficients ranging from 0.74 to 0.90 for subscales, and item-to-total correlations and inter-item correlations exceeded accepted thresholds of 0.50 and 0.30, respectively. Convergent validity was acceptable between the PTGI compassion subscale and DPES (r = 0.50). Compassion is a highly salient PTG domain after prostate cancer. Further studies can explore this construct with more heterogeneous samples of cancer types and gender.

  20. Problem-Solving Test: The Role of Ubiquitination in Epidermal Growth Factor Receptor Trafficking

    ERIC Educational Resources Information Center

    Szeberenyi, Jozsef

    2012-01-01

    Terms to be familiar with before you start to solve the test: growth factor signaling, epidermal growth factor, tyrosine protein kinase, tyrosine phosphorylation, ubiquitin, monoubiquitination, polyubiquitination, site-directed mutagenesis, transfection, expression vector, cDNA, immunoprecipitation, SDS-polyacrylamide gel electrophoresis, Western…

  1. Density-dependent regulation of growth of BSC-1 cells in cell culture: control of growth by serum factors.

    PubMed Central

    Holley, R W; Armour, R; Baldwin, J H; Brown, K D; Yeh, Y C

    1977-01-01

    BSC-1 cells grow slowly, to high cell density, in medium with 0.1% calf serum. An increase in the serum concentration increases both the growth rate of the cells and the final cell density. The serum can be replaced to some extent by epidermal growth factor (EGF). Initiation of DNA synthesis in BSC-1 cells that have spread into a "wound" in a crowded cell layer requires the addition of a trace of serum or EGF, if the cells have previously been deprived of serum. The binding of 125I-labeled EGF to low-density and high-density BSC-1 cells has been studied. Binding is faster to low-density cells. Cells at low cell density also bind much more EGF per cell than cells at high cell density. The fraction of bound 125I-labeled EGF that is present on the cell surface as intact EGF is larger at low than at high cell density. The results indicate that the number of available EGF receptors per cell decreases drastically as the cell density increases. It is suggested that a decrease in the number of available EGF receptor sites per cell, and the accompanying decrease in sensitivity of the cells to EGF, contributes to density-dependent regulation of growth of these cells. Images PMID:303774

  2. Small angle neutron scattering study of sodium dodecyl sulfate micellar growth driven by addition of a hydrotropic salt.

    PubMed

    Hassan, P A; Fritz, Gerhard; Kaler, Eric W

    2003-01-01

    The structures of aggregates formed in aqueous solutions of an anionic surfactant, sodium dodecyl sulfate (SDS), with the addition of a cationic hydrotropic salt, p-toluidine hydrochloride (PTHC), have been investigated by small angle neutron scattering (SANS). The SANS spectra exhibit a pronounced peak at low salt concentration, indicating the presence of repulsive intermicellar interactions. Model-independent real space information about the structure is obtained from a generalized indirect Fourier transformation (GIFT) technique in combination with a suitable model for the interparticle structure factor. The interparticle interaction is captured using the rescaled mean spherical approximation (RMSA) closure relation and a Yukawa form of the interaction potential. Further quantification of the geometrical parameters of the micelles was achieved by a complete fit of the SANS data using a prolate ellipsoidal form factor and the RMSA structure factor. The present study shows that PTHC induces a decrease in the fractional charge of the micelles due to adsorption at the micellar surface and consequent growth of the SDS micelles from nearly globular to rodlike as the concentration of PTHC increases.

  3. Recent research on the growth plate: Advances in fibroblast growth factor signaling in growth plate development and disorders.

    PubMed

    Xie, Yangli; Zhou, Siru; Chen, Hangang; Du, Xiaolan; Chen, Lin

    2014-08-01

    Skeletons are formed through two distinct developmental actions, intramembranous ossification and endochondral ossification. During embryonic development, most bone is formed by endochondral ossification. The growth plate is the developmental center for endochondral ossification. Multiple signaling pathways participate in the regulation of endochondral ossification. Fibroblast growth factor (FGF)/FGF receptor (FGFR) signaling has been found to play a vital role in the development and maintenance of growth plates. Missense mutations in FGFs and FGFRs can cause multiple genetic skeletal diseases with disordered endochondral ossification. Clarifying the molecular mechanisms of FGFs/FGFRs signaling in skeletal development and genetic skeletal diseases will have implications for the development of therapies for FGF-signaling-related skeletal dysplasias and growth plate injuries. In this review, we summarize the recent advances in elucidating the role of FGFs/FGFRs signaling in growth plate development, genetic skeletal disorders, and the promising therapies for those genetic skeletal diseases resulting from FGFs/FGFRs dysfunction. Finally, we also examine the potential important research in this field in the future. © 2014 Society for Endocrinology.

  4. The Antimicrobial Peptide Human Beta-Defensin-3 Is Induced by Platelet-Released Growth Factors in Primary Keratinocytes

    PubMed Central

    Lammel, Justus; Tohidnezhad, Mersedeh; Lippross, Sebastian; Behrendt, Peter; Klüter, Tim; Pufe, Thomas; Cremer, Jochen; Jahr, Holger; Rademacher, Franziska; Gläser, Regine; Harder, Jürgen

    2017-01-01

    Platelet-released growth factors (PRGF) and its related clinically used formulations (e.g., Vivostat Platelet-Rich Fibrin (PRF®)) contain a variety of chemokines, cytokines, and growth factors and are therefore used to support healing of chronic, hard-to-heal, or infected wounds. Human beta-defensin-3 (hBD-3) is an antimicrobial peptide inducibly expressed in human keratinocytes especially upon wounding. The potent antimicrobial activity of hBD-3 together with its wound closure-promoting activities suggests that hBD-3 may play a crucial role in wound healing. Therefore, we analyzed the influence of PRGF on hBD-3 expression in human primary keratinocytes in vitro. In addition, we investigated the influence of Vivostat PRF on hBD-3 expression in artificially generated human skin wounds in vivo. PRGF treatment of primary keratinocytes induced a significant, concentration- and time-dependent increase in hBD-3 gene expression which was partially mediated by the epidermal growth factor receptor (EGFR). In line with these cell culture data, in vivo experiments revealed an enhanced hBD-3 expression in experimentally produced human wounds after the treatment with Vivostat PRF. Thus, the induction of hBD-3 may contribute to the beneficial effects of thrombocyte concentrate lysates in the treatment of chronic or infected wounds. PMID:28811680

  5. Growth Factor Stimulation Improves the Structure and Properties of Scaffold-Free Engineered Auricular Cartilage Constructs

    PubMed Central

    Rosa, Renata G.; Joazeiro, Paulo P.; Bianco, Juares; Kunz, Manuela; Weber, Joanna F.; Waldman, Stephen D.

    2014-01-01

    The reconstruction of the external ear to correct congenital deformities or repair following trauma remains a significant challenge in reconstructive surgery. Previously, we have developed a novel approach to create scaffold-free, tissue engineering elastic cartilage constructs directly from a small population of donor cells. Although the developed constructs appeared to adopt the structural appearance of native auricular cartilage, the constructs displayed limited expression and poor localization of elastin. In the present study, the effect of growth factor supplementation (insulin, IGF-1, or TGF-β1) was investigated to stimulate elastogenesis as well as to improve overall tissue formation. Using rabbit auricular chondrocytes, bioreactor-cultivated constructs supplemented with either insulin or IGF-1 displayed increased deposition of cartilaginous ECM, improved mechanical properties, and thicknesses comparable to native auricular cartilage after 4 weeks of growth. Similarly, growth factor supplementation resulted in increased expression and improved localization of elastin, primarily restricted within the cartilaginous region of the tissue construct. Additional studies were conducted to determine whether scaffold-free engineered auricular cartilage constructs could be developed in the 3D shape of the external ear. Isolated auricular chondrocytes were grown in rapid-prototyped tissue culture molds with additional insulin or IGF-1 supplementation during bioreactor cultivation. Using this approach, the developed tissue constructs were flexible and had a 3D shape in very good agreement to the culture mold (average error <400 µm). While scaffold-free, engineered auricular cartilage constructs can be created with both the appropriate tissue structure and 3D shape of the external ear, future studies will be aimed assessing potential changes in construct shape and properties after subcutaneous implantation. PMID:25126941

  6. Growth Factors and COX2 Expression in Canine Perivascular Wall Tumors.

    PubMed

    Avallone, G; Stefanello, D; Boracchi, P; Ferrari, R; Gelain, M E; Turin, L; Tresoldi, E; Roccabianca, P

    2015-11-01

    Canine perivascular wall tumors (PWTs) are a group of subcutaneous soft tissue sarcomas developing from vascular mural cells. Mural cells are involved in angiogenesis through a complex crosstalk with endothelial cells mediated by several growth factors and their receptors. The evaluation of their expression may have relevance since they may represent a therapeutic target in the control of canine PWTs. The expression of vascular endothelial growth factor (VEGF) and receptors VEGFR-I/II, basic fibroblast growth factor (bFGF) and receptor Flg, platelet-derived growth factor B (PDGFB) and receptor PDGFRβ, transforming growth factor β1 (TGFβ1) and receptors TGFβR-I/II, and cyclooxygenase 2 (COX2) was evaluated on frozen sections of 40 PWTs by immunohistochemistry and semiquantitatively scored to identify their potential role in PWT development. Statistical analysis was performed to analyze possible correlations between Ki67 labeling index and the expression of each molecule. Proteins of the VEGF-, PDGFB-, and bFGF-mediated pathways were highly expressed in 27 (67.5%), 30 (75%), and 19 (47.5%) of 40 PWTs, respectively. Proteins of the TGFβ1- and COX2-mediated pathways were highly expressed in 4 (10%) and 14 (35%) of 40 cases. Statistical analysis identified an association between VEGF and VEGFR-I/II (P = .015 and .003, respectively), bFGF and Flg (P = .038), bFGF and PDGFRβ (P = .003), and between TGFβ1 and COX2 (P = .006). These findings were consistent with the mechanisms that have been reported to play a role in angiogenesis and in tumor development. No association with Ki67 labeling index was found. VEGF-, PDGFB-, and bFGF-mediated pathways seem to have a key role in PWT development and growth. Blockade of tyrosine kinase receptors after surgery could represent a promising therapy with the aim to reduce the PWT relapse rate and prolong the time to relapse. © The Author(s) 2015.

  7. Multifunctional mesoporous bioactive glasses for effective delivery of therapeutic ions and drug/growth factors.

    PubMed

    Wu, Chengtie; Chang, Jiang

    2014-11-10

    Regeneration of large-size bone defects represents a significant challenge clinically, which requires the use of scaffolds with multifunction, such as anti-bacterial activity, and stimulation of osteogenesis and angiogenesis. It is known that functional ions or drug/growth factors play an important role to stimulate tissue regeneration. Mesoporous bioactive glasses (MBG) possess excellent bioactivity and drug-delivery ability as well as effective ionic release in the body fluids microenvironment due to its specific mesoporous structure and large surface area. For these reasons, functional ions (e.g. lithium (Li), strontium (Sr), Copper (Cu) and Boron (B)) and drug/growth factors (e.g. dexamethasone, vascular endothelial growth factor (VEGF) and bone morphogenetic protein (BMP)) have been incorporated into MBG, which shows high loading efficiency and effective release. The release of therapeutic ions and drug/growth factors from MBG offers it multifunctional properties, such as improved osteogenesis, angiogenesis, anti-bacterial/cancer activity. However, there is no a systematic review about delivery of therapeutic ions and drugs/growth factors from MBG for the functional effect on the tissue regeneration despite that significant progress has been achieved in the past five years. Therefore, in this review, we mainly focused on the new advances for the functional effect of delivering therapeutic ions and drugs/growth factors on the ostegeogenesis, angiogenesis and antibacterial activity. It is expected that the review will offer new concept to develop multifunctional biomaterials for bone regeneration by the synergistic effect of therapeutic ions and drug/growth factors. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Determination of optimized growth medium and cryoprotective additives to enhance the growth and survival of Lactobacillus salivarius.

    PubMed

    Yeo, Soyoung; Shin, Hee Sung; Lee, Hye Won; Hong, Doseon; Park, Hyunjoon; Holzapfel, Wilhelm; Kim, Eun Bae; Huh, Chul Sung

    2018-03-16

    Beneficial effects of lactic acid bacteria (LAB) have been intensively investigated in recent decades with special focus on modulation of the host intestinal microbiota. Numerous discoveries of effective probiotics are driven by a significantly increasing demand for dietary supplements. Consequently, technological advances in the large-scale production and lyophilization are needed by probiotic-related industries for producing probiotic LAB for commercial use. Our study had a dual objective, i.e., to determine the optimum growth medium composition and to investigate appropriate cryoprotective additives (CPAs) for Lactobacillus salivarius , and compare its responses with other Lactobacillus species. The one-factor-at-a-time method and central composite design were applied to determine the optimal medium composition for L. salivarius cultivation. The following composition of the medium was established (per liter): 21.64 g maltose, 85 g yeast extract, 1.21 ml Tween 80, 6 g sodium acetate, 0.2 g MgSO 4 ∙7H 2 O, 0.02 g MnSO 4 ∙H 2 O, 1 g K 2 HPO 4 , 1.5 g KH 2 PO 4 , 0.01 g FeSO 4 ∙7H 2 O and 1 g sodium citrate. A cryoprotective additive combination comprising 10% ( w/v ) skim milk and 10% ( w/v ) sucrose supplemented with 2.5% ( w/v ) sodium glutamate was selected for L. salivarius , and its effectiveness was confirmed using culture-independent methods in the freeze-dried cells of the Lactobacillus strains. In conclusion, the optimized medium enhanced the species-specific cultivation of L. salivarius . On the other hand, the cryoprotective effects of the selected CPA mixture may also be dependent on the bacterial strain. This study highlights the necessity for precise and advanced processing techniques for large-scale production of probiotics in the food and feed industries.

  9. Overexpression of Heparin-Binding Epidermal Growth Factor-Like Growth Factor Mediates Liver Fibrosis in Transgenic Mice.

    PubMed

    Guo, Yongze; Ding, Qian; Chen, Lei; Ji, Chenguang; Hao, Huiyao; Wang, Jia; Qi, Wei; Xie, Xiaoli; Ma, Junji; Li, Aidi; Jiang, Xiaoyu; Li, Xiaotian; Jiang, Huiqing

    2017-08-01

    The role of heparin-binding epidermal growth factor-like growth factor (HB-EGF) in liver fibrosis is not clear and is sometimes even contradictory. To clarify this role, a HB-EGF transgenic (Tg) mouse model was, for the first time, used to evaluate the functions of HB-EGF in liver fibrosis. For the in vivo study, carbon tetrachloride injection and bile duct ligation treatment were used to induce liver fibrosis in HB-EGF Tg mice and wild-type (WT) mice, respectively. Primary hepatic satellite cells (HSCs) were isolated from HB-EGF Tg and WT mice for the in vitro study. Compared with the WT mice, HB-EGF Tg mice were shown to develop more severe liver fibrosis when treated with carbon tetrachloride or bile duct ligation, with increased matrix metalloproteinases 13 activity and enhanced expression of fibrogenic genes including α-smooth muscle actin and collagen I. HB-EGF gene transfer led to an increase in proliferation and a decrease in apoptosis in primary HSCs. The ERK signaling pathway was more highly activated in primary HSCs from HB-EGF Tg mice than in those from WT mice. Our investigation confirmed the profibrotic effect of HB-EGF on the liver using a Tg mouse model. This result may contribute to the elucidation of HB-EGF as a therapeutic target in liver fibrosis. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  10. Soil-Site Factors Affecting Southern Upland Oak Managment and Growth

    Treesearch

    John K. Francis

    1980-01-01

    Soil supplies trees with physical support, moisture, oxygen, and nutrients. Amount of moisture most limits tree growth; and soil and topographic factors such as texture and aspect, which influence available soil moisture. are most useful in predicting growth. Equations that include soil and topographic variables can be used to predict site index. Foresters can also...

  11. Effect of transforming growth factor beta (TGF-β) receptor I kinase inhibitor on prostate cancer bone growth.

    PubMed

    Wan, Xinhai; Li, Zhi-Gang; Yingling, Jonathan M; Yang, Jun; Starbuck, Michael W; Ravoori, Murali K; Kundra, Vikas; Vazquez, Elba; Navone, Nora M

    2012-03-01

    Transforming growth factor beta 1 (TGF-β1) has been implicated in the pathogenesis of prostate cancer (PCa) bone metastasis. In this study, we tested the antitumor efficacy of a selective TGF-β receptor I kinase inhibitor, LY2109761, in preclinical models. The effect of LY2109761 on the growth of MDA PCa 2b and PC-3 human PCa cells and primary mouse osteoblasts (PMOs) was assessed in vitro by measuring radiolabeled thymidine incorporation into DNA. In vivo, the right femurs of male SCID mice were injected with PCa cells. We monitored the tumor burden in control- and LY2109761-treated mice with MRI analysis and the PCa-induced bone response with X-ray and micro-CT analyses. Histologic changes in bone were studied by performing bone histomorphometric evaluations. PCa cells and PMOs expressed TGF-β receptor I. TGF-β1 induced pathway activation (as assessed by induced expression of p-Smad2) and inhibited cell growth in PC-3 cells and PMOs but not in MDA PCa 2b cells. LY2109761 had no effect on PCa cells but induced PMO proliferation in vitro. As expected, LY2109761 reversed the TGF-β1-induced pathway activation and growth inhibition in PC-3 cells and PMOs. In vivo, LY2109761 treatment for 6weeks resulted in increased volume in normal bone and increased osteoblast and osteoclast parameters. In addition, LY2109761 treatment significantly inhibited the growth of MDA PCa 2b and PC-3 in the bone of SCID mice (p<0.05); moreover, it resulted in significantly less bone loss and change in osteoclast-associated parameters in the PC-3 tumor-bearing bones than in the untreated mice. In summary, we report for the first time that targeting TGF-β receptors with LY2109761 can control PCa bone growth while increasing the mass of normal bone. This increased bone mass in nontumorous bone may be a desirable side effect of LY2109761 treatment for men with osteopenia or osteoporosis secondary to androgen-ablation therapy, reinforcing the benefit of effectively controlling PCa growth

  12. Effect of transforming growth factor beta (TGF-β) receptor I kinase inhibitor on prostate cancer bone growth

    PubMed Central

    Wan, Xinhai; Li, Zhi-Gang; Yingling, Jonathan M.; Yang, Jun; Starbuck, Michael W.; Ravoori, Murali K.; Kundra, Vikas; Vazquez, Elba; Navone, Nora M.

    2012-01-01

    Transforming growth factor beta 1 (TGF-β1) has been implicated in the pathogenesis of prostate cancer (PCa) bone metastasis. In this study, we tested the antitumor efficacy of a selective TGF-β receptor I kinase inhibitor, LY2109761, in preclinical models. The effect of LY2109761 on the growth of MDA PCa 2b and PC-3 human PCa cells and primary mouse osteoblasts (PMOs) was assessed in vitro by measuring radiolabeled thymidine incorporation into DNA. In vivo, the right femurs of male SCID mice were injected with PCa cells. We monitored the tumor burden in control- and LY2109761-treated mice with MRI analysis and the PCa-induced bone response with x-ray and micro-CT analyses. Histologic changes in bone were studied by performing bone histomorphometric evaluations. PCa cells and PMOs expressed TGF-β receptor I. TGF-β1 induced pathway activation (as assessed by induced expression of p-Smad2) and inhibited cell growth in PC-3 cells and PMOs but not in MDA PCa 2b cells. LY2109761 had no effect on PCa cells but induced PMO proliferation in vitro. As expected, LY2109761 reversed the TGF-β1–induced pathway activation and growth inhibition in PC-3 cells and PMOs. In vivo, LY2109761 treatment for 6 weeks resulted in increased volume in normal bone and increased osteoblast and osteoclast parameters. In addition, LY2109761 treatment significantly inhibited the growth of MDA PCa 2b and PC-3 in the bone of SCID mice (p < 0.05); moreover, it resulted in significantly less bone loss and change in osteoclast-associated parameters in the PC-3 tumor–bearing bones than in the untreated mice. In summary, we report for the first time that targeting TGF-β receptors with LY2109761 can control PCa bone growth while increasing the mass of normal bone. This increased bone mass in nontumorous bone may be a desirable side effect of LY2109761 treatment for men with osteopenia or osteoporosis secondary to androgen-ablation therapy, reinforcing the benefit of effectively controlling PCa

  13. Growth and mycorrhizal community structure of Pinus sylvestris seedlings following the addition of forest litter.

    PubMed

    Aucina, Algis; Rudawska, Maria; Leski, Tomasz; Skridaila, Audrius; Riepsas, Edvardas; Iwanski, Michal

    2007-08-01

    We report the effects of pine and oak litter on species composition and diversity of mycorrhizal fungi colonizing 2-year-old Pinus sylvestris L. seedlings grown in a bare-root nursery in Lithuania. A layer of pine or oak litter was placed on the surface of the nursery bed soil to mimic natural litter cover. Oak litter amendment appeared to be most favorable for seedling survival, with a 73% survival rate, in contrast to the untreated mineral bed soil (44%). The concentrations of total N, P, K, Ca, and Mg were higher in oak growth medium than in pine growth medium. Relative to the control (pH 6.1), the pH was lower in pine growth medium (5.8) and higher in oak growth medium (6.3). There were also twofold and threefold increases in the C content of growth medium with the addition of pine and oak litter, respectively. Among seven mycorrhizal morphotypes, eight different mycorrhizal taxa were identified: Suillus luteus, Suillus variegatus, Wilcoxina mikolae, a Tuber sp., a Tomentella sp., Cenococcum geophilum, Amphinema byssoides, and one unidentified ectomycorrhizal symbiont. Forest litter addition affected the relative abundance of mycorrhizal symbionts more than their overall representation. This was more pronounced for pine litter than for oak litter, with 40% and 25% increases in the abundance of suilloid mycorrhizae, respectively. Our findings provide preliminary evidence that changes in the supply of organic matter through litter manipulation may have far-reaching effects on the chemistry of soil, thus influencing the growth and survival of Scots pine seedlings and their mycorrhizal communities.

  14. Fibroblast Growth Factor 23 in Long-Duration Spaceflight

    NASA Technical Reports Server (NTRS)

    Bokhari, R.; Zwart, S. R.; Fields, E.; Heer, M.; Sibonga, J.; Smith, S. M.

    2015-01-01

    Many nutritional factors influence bone, from the basics of calcium and vitamin D, to factors which influence bone through acid/base balance, including protein, sodium, and more. Fibroblast growth factor 23 (FGF23) is a recently identified factor, secreted from osteocytes, which is involved in classic (albeit complex) feedback loops controlling phosphorus homeostasis through both vitamin D and parathyroid hormone (PTH) (1, 2). As osteocytes are gravity sensing cells, it is important to determine if there are changes in FGF23 during spaceflight. In extreme cases, such as chronic kidney disease, FGF23 levels are highly elevated. FGF23 imbalances, secondary to dietary influences, may contribute to skeletal demineralization and kidney stone risk during spaceflight.

  15. Niclosamide inhibits epithelial-mesenchymal transition and tumor growth in lapatinib-resistant human epidermal growth factor receptor 2-positive breast cancer.

    PubMed

    Liu, Junjun; Chen, Xiaosong; Ward, Toby; Mao, Yan; Bockhorn, Jessica; Liu, Xiaofei; Wang, Gen; Pegram, Mark; Shen, Kunwei

    2016-02-01

    Acquired resistance to lapatinib, a human epidermal growth factor receptor 2 kinase inhibitor, remains a clinical problem for women with human epidermal growth factor receptor 2-positive advanced breast cancer, as metastasis is commonly observed in these patients. Niclosamide, an anti-helminthic agent, has recently been shown to exhibit cytotoxicity to tumor cells with stem-like characteristics. This study was designed to identify the mechanisms underlying lapatinib resistance and to determine whether niclosamide inhibits lapatinib resistance by reversing epithelial-mesenchymal transition. Here, two human epidermal growth factor receptor 2-positive breast cancer cell lines, SKBR3 and BT474, were exposed to increasing concentrations of lapatinib to establish lapatinib-resistant cultures. Lapatinib-resistant SKBR3 and BT474 cells exhibited up-regulation of the phenotypic epithelial-mesenchymal transition markers Snail, vimentin and α-smooth muscle actin, accompanied by activation of nuclear factor-кB and Src and a concomitant increase in stem cell marker expression (CD44(high)/CD24(low)), compared to naive lapatinib-sensitive SKBR3 and BT474 cells, respectively. Interestingly, niclosamide reversed epithelial-mesenchymal transition, induced apoptosis and inhibited cell growth by perturbing aberrant signaling pathway activation in lapatinib-resistant human epidermal growth factor receptor 2-positive cells. The ability of niclosamide to alleviate stem-like phenotype development and invasion was confirmed. Collectively, our results demonstrate that lapatinib resistance correlates with epithelial-mesenchymal transition and that niclosamide inhibits lapatinib-resistant cell viability and epithelial-mesenchymal transition. These findings suggest a role of niclosamide or derivatives optimized for more favorable bioavailability not only in reversing lapatinib resistance but also in reducing metastatic potential during the treatment of human epidermal growth factor receptor

  16. Enhancing hair growth in male androgenetic alopecia by a combination of fractional CO2 laser therapy and hair growth factors.

    PubMed

    Huang, Yue; Zhuo, Fenglin; Li, Linfeng

    2017-11-01

    Laser therapy and growth factors have been used as alternative treatments for male androgenetic alopecia (MAA). The aim of this study is to determine the efficacy and safety of hair growth factors alone or combined with ablative carbon dioxide (CO 2 ) fractional laser therapy in MAA. Twenty-eight men were enrolled in this randomized half-split study based on a left-head to right-head pattern. Fractional CO 2 laser treatment was unilaterally performed; hair growth factors were bilaterally applied. Six sessions with 2-week intervals were performed. Global photographs and dermoscopy assessments were performed at the baseline and 4 months after first treatment. Global photographs underwent blinded review by three independent dermatologists. Scanning electron microscopy was used to compare changes in hair-follicle phase and hair-shaft diameter. Twenty-seven participants completed the 4-month treatment schedule. One patient was lost. Mean hair density increased from 114 ± 27 to 143 ± 25/cm 2 (P < 0.001) in the combined group and from 113 ± 24 to 134 ± 19/cm 2 in the growth factor group (P < 0.001). The mean change from baseline between two groups was also compared (P = 0.003). Global photographs showed improvement in 93% (25/27) patients in the combined group and 67% (18/27) patients in the growth factor group. Under scanning electron microscopy, hair follicles appeared to transition from telogen to anagen, and hair-shaft diameter increased in five randomly selected patients. Ablative fractional CO 2 laser combined with hair growth factors may serve as an alternative treatment for MAA in individuals unwilling/unable to undergo medical or surgical treatment.

  17. Peripheral blood "endothelial progenitor cells" are derived from monocyte/macrophages and secrete angiogenic growth factors.

    PubMed

    Rehman, Jalees; Li, Jingling; Orschell, Christie M; March, Keith L

    2003-03-04

    Endothelial progenitor cells (EPCs) have been isolated from peripheral blood and can enhance angiogenesis after infusion into host animals. It is not known whether the proangiogenic effects are a result of such events as endothelial differentiation and subsequent proliferation of EPCs or secondary to secretion of angiogenic growth factors. Human EPCs were isolated as previously described, and their phenotypes were confirmed by uptake of acetylated LDL and binding of ulex-lectin. EPC proliferation and surface marker expression were analyzed by flow cytometry, and conditioned medium was assayed for growth factors. The majority of EPCs expressed monocyte/macrophage markers such as CD14 (95.7+/-0.3%), Mac-1 (57.6+/-13.5%), and CD11c (90.8+/-4.9%). A much lower percentage of cells expressed the specific endothelial marker VE-cadherin (5.2+/-0.7%) or stem/progenitor-cell markers AC133 (0.16+/-0.05%) and c-kit (1.3+/-0.7%). Compared with circulating monocytes, cultured EPCs showed upregulation of monocyte activation and macrophage differentiation markers. EPCs did not demonstrate any significant proliferation but did secrete the angiogenic growth factors vascular endothelial growth factor, hepatocyte growth factor, granulocyte colony-stimulating factor, and granulocyte-macrophage colony-stimulating factor. Our findings suggest that acetylated LDL(+)ulex-lectin(+) cells, commonly referred to as EPCs, do not proliferate but release potent proangiogenic growth factors. The majority of acetylated LDL(+)ulex-lectin(+) cells are derived from monocyte/macrophages. The findings of low proliferation and endothelial differentiation suggest that their angiogenic effects are most likely mediated by growth factor secretion. These findings may allow for development of novel angiogenic therapies relying on secreted growth factors or on recruitment of endogenous monocytes/macrophages to sites of ischemia.

  18. Study of metal whiskers growth and mitigation technique using additive manufacturing

    NASA Astrophysics Data System (ADS)

    Gullapalli, Vikranth

    For years, the alloy of choice for electroplating electronic components has been tin-lead (Sn-Pb) alloy. However, the legislation established in Europe on July 1, 2006, required significant lead (Pb) content reductions from electronic hardware due to its toxic nature. A popular alternative for coating electronic components is pure tin (Sn). However, pure tin has the tendency to spontaneously grow electrically conductive Sn whisker during storage. Sn whisker is usually a pure single crystal tin with filament or hair-like structures grown directly from the electroplated surfaces. Sn whisker is highly conductive, and can cause short circuits in electronic components, which is a very significant reliability problem. The damages caused by Sn whisker growth are reported in very critical applications such as aircraft, spacecraft, satellites, and military weapons systems. They are also naturally very strong and are believed to grow from compressive stresses developed in the Sn coating during deposition or over time. The new directive, even though environmentally friendly, has placed all lead-free electronic devices at risk because of whisker growth in pure tin. Additionally, interest has occurred about studying the nature of other metal whiskers such as zinc (Zn) whiskers and comparing their behavior to that of Sn whiskers. Zn whiskers can be found in flooring of data centers which can get inside electronic systems during equipment reorganization and movement and can also cause systems failure. Even though the topic of metal whiskers as reliability failure has been around for several decades to date, there is no successful method that can eliminate their growth. This thesis will give further insights towards the nature and behavior of Sn and Zn whiskers growth, and recommend a novel manufacturing technique that has potential to mitigate metal whiskers growth and extend life of many electronic devices.

  19. Mitogenic signaling pathways of growth factors can be distinguished by the involvement of pertussis toxin-sensitive guanosine triphosphate-binding protein and of protein kinase C.

    PubMed Central

    Nishizawa, N; Okano, Y; Chatani, Y; Amano, F; Tanaka, E; Nomoto, H; Nozawa, Y; Kohno, M

    1990-01-01

    We have examined the possible involvements of pertussis toxin (PT)-sensitive guanosine triphosphate (GTP)-binding protein (Gp) and protein kinase C (PKC) in the mitogenic signaling pathways of various growth factors by the use of PT-pretreated and/or 12-O-tetradecanoyl phorbol-13-acetate (TPA)-pretreated mouse fibroblasts. Effects of PT pretreatment (inactivation of PT-sensitive Gp) and TPA pretreatment (depletion of PKC) on mitogen-induced DNA synthesis varied significantly and systematically in response to growth factors: mitogenic responses of cells to thrombin, bombesin, and bradykinin were almost completely abolished both in PT- and TPA-pretreated cells; responses to epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and vanadate were reduced to approximately 50% both in PT- and TPA-pretreated cells compared with native cells; response to basic fibroblast growth factor (bFGF) was not affected in PT-pretreated cells but was inhibited to some extent in TPA-pretreated cells. Thus, growth factors examined have been classified into three groups with regard to the involvements of PT-sensitive Gp and PKC in their signal transduction pathways. Binding of each growth factor to its receptor was not affected significantly by pretreatment of cells with PT or TPA. Inhibitory effects of PT and TPA pretreatment on each mitogen-induced DNA synthesis were not additive, suggesting that the functions of PT-sensitive Gp and PKC lie on an identical signal transduction pathway. Although all three groups of mitogens activated PKC, signaling of each growth factor depends to a varying extent on the function of PKC. Our results indicate that a single peptide growth factor such as EGF, PDGF, or bFGF acts through multiple signaling pathways to induce cell proliferation. Images PMID:2129194

  20. Differential growth factor control of bone formation through osteoprogenitor differentiation.

    PubMed

    Chaudhary, L R; Hofmeister, A M; Hruska, K A

    2004-03-01

    The osteogenic factors bone morphogenetic protein (BMP-7), platelet-derived growth factor (PDGF)-BB, and fibroblast growth factor (FGF-2) regulate the recruitment of osteoprogenitor cells and their proliferation and differentiation into mature osteoblasts. However, their mechanisms of action on osteoprogenitor cell growth, differentiation, and bone mineralization remain unclear. Here, we tested the hypothesis that these osteogenic agents were capable of regulating osteoblast differentiation and bone formation in vitro. Normal human bone marrow stromal (HBMS) cells were treated with BMP-7 (40 ng ml(-1)), PDGF-BB (20 ng ml(-1)), FGF-2 (20 ng ml(-1)), or FGF-2 plus BMP-7 for 28 days in a serum-containing medium with 10 mM beta-glycerophosphate and 50 microg ml(-1) ascorbic acid. BMP-7 stimulated a morphological change to cuboidal-shaped cells, increased alkaline phosphatase (ALKP) activity, bone sialoprotein (BSP) gene expression, and alizarin red S positive nodule formation. Hydroxyapatite (HA) crystal deposition in the nodules was demonstrated by Fourier transform infrared (FTIR) spectroscopy only in BMP-7- and dexamethasone (DEX)-treated cells. DEX-treated cells appeared elongated and fibroblast-like compared to BMP-7-treated cells. FGF-2 did not stimulate ALKP, and cell morphology was dystrophic. PDGF-BB had little or no effect on ALKP activity and biomineralization. Alizarin Red S staining of cells and calcium assay indicated that BMP-7, DEX, and FGF-2 enhanced calcium mineral deposition, but FTIR spectroscopic analysis demonstrated no formation of HA similar to human bone in control, PDGF-BB-, and FGF-2-treated samples. Thus, FGF-2 stimulated amorphous octacalcium phosphate mineral deposition that failed to mature into HA. Interestingly, FGF-2 abrogated BMP-7-induced ALKP activity and HA formation. Results demonstrate that BMP-7 was competent as a sole factor in the differentiation of human bone marrow stromal cells to bone-forming osteoblasts confirmed by FTIR

  1. The statistical mechanics of complex signaling networks: nerve growth factor signaling

    NASA Astrophysics Data System (ADS)

    Brown, K. S.; Hill, C. C.; Calero, G. A.; Myers, C. R.; Lee, K. H.; Sethna, J. P.; Cerione, R. A.

    2004-10-01

    The inherent complexity of cellular signaling networks and their importance to a wide range of cellular functions necessitates the development of modeling methods that can be applied toward making predictions and highlighting the appropriate experiments to test our understanding of how these systems are designed and function. We use methods of statistical mechanics to extract useful predictions for complex cellular signaling networks. A key difficulty with signaling models is that, while significant effort is being made to experimentally measure the rate constants for individual steps in these networks, many of the parameters required to describe their behavior remain unknown or at best represent estimates. To establish the usefulness of our approach, we have applied our methods toward modeling the nerve growth factor (NGF)-induced differentiation of neuronal cells. In particular, we study the actions of NGF and mitogenic epidermal growth factor (EGF) in rat pheochromocytoma (PC12) cells. Through a network of intermediate signaling proteins, each of these growth factors stimulates extracellular regulated kinase (Erk) phosphorylation with distinct dynamical profiles. Using our modeling approach, we are able to predict the influence of specific signaling modules in determining the integrated cellular response to the two growth factors. Our methods also raise some interesting insights into the design and possible evolution of cellular systems, highlighting an inherent property of these systems that we call 'sloppiness.'

  2. A high ratio of insulin-like growth factor II/insulin-like growth factor binding protein 2 messenger RNA as a marker for anaplasia in meningiomas.

    PubMed

    Nordqvist, A C; Peyrard, M; Pettersson, H; Mathiesen, T; Collins, V P; Dumanski, J P; Schalling, M

    1997-07-01

    Insulin-like growth factors (IGFs) I and II have been implicated as autocrine or paracrine growth promoters. These growth factors bind to specific receptors, and the response is modulated by interaction with IGF-binding proteins (IGFBPs). We observed a strong correlation between anaplastic/atypical histopathology and a high IGF-II/IGFBP-2 mRNA ratio in a set of 68 sporadic meningiomas. A strong correlation was also found between clinical outcome and IGF-II/IGFBP-2 ratio, whereas previously used histochemical markers were less correlated to outcome. We suggest that a high IGF-II/IGFBP-2 mRNA ratio may be a sign of biologically aggressive behavior in meningiomas that can influence treatment strategies. We propose that low IGFBP-2 levels in combination with increased levels of IGF-II would result in more free IGF-II and consequently greater stimulation of proliferation.

  3. Can insulin-like growth factor 1 (IGF-1), IGF-1 receptor connective tissue growth factor and Ki-67 labelling index have a prognostic role in pulmonary carcinoids?

    PubMed

    Kanakis, Georgios A; Grimelius, Lars; Papaioannou, Dimitrios; Kaltsas, Gregory; Tsolakis, Apostolos V

    2018-04-27

    Altered expression of Insulin-like Growth Factor-1 (IGF-1), its receptor (IGF-1R), Connective Tissue Growth Factor (CTGF) and Hypoxia Inducible Factor-1 (HIF-1), has been implicated in tumorigenesis. So far, these factors have not been studied systematically in Pulmonary Carcinoids (PCs). To examine IGF-1, IGF-1R, CTGF and HIF-1 expression in PCs, and assess their prognostic value over established factors. Retrospective study of 121 PCs (104 Typical and 17 Atypical). The expression of growth factors was studied immunohistochemically and tumors were considered positive if immunoreactivity appeared in >50% of cells. All studied parameters were expressed in the majority of tumors (IGF-1, IGF-1R, CTGF and HIF-1, in 78.5%, 67%, 72% and 78%, respectively). Their expression tended to be more frequent in TCs and in tumors with Ki-67≤2% (significant only for HIF-1; 82 vs. 53%; p=0.023 and 83 vs. 63%; p=0.025 respectively). CTGF was the only factor correlated with more extensive disease (larger size; presence of lymph node and distant metastases). According to logistic regression analysis, only advanced age, Ki-67≥3.4% and lymph node involvement could predict the development of distant metastases. IGF-1, IGF-1R, CTGF and HIF-1 are avidly expressed in PCs; however, their presence did not appear to be of statistically significant value over established prognostic factors.

  4. The role of nerve growth factor in the prophylaxis and treatment of diabetic foot ulcers

    PubMed Central

    Tiaka, Elisavet K; Papanas, Nikolaos; Manolakis, Anastassios C; Maltezos, Efstratios

    2011-01-01

    Diabetic foot ulcers are still particularly difficult to heal. Therefore, preventing and therapeutic adjuncts are increasingly being explored. Nerve growth factor (NGF) is a promising agent exhibiting beneficial actions on both diabetic peripheral neuropathy, one of the main causes of foot ulcers, and on ulcer healing. Indeed, preclinical research in animal models of diabetes has revealed the trophic effect of NGF on small C-fibres, while phase 2 human trials have provided evidence for a favourable effect on sensory neuropathy. However, the results of a phase 3 trial were moderate and, therefore, not enough to encourage widespread use of NGF in the treatment of diabetic neuropathy. Available literature on the role of NGF on diabetic wound healing is sparse but encouraging. Exogenous supplementation of NGF or the use of alternative techniques to increase its endogenous expression could emerge as a protective and therapeutic modality for diabetic foot ulcers in addition to standard treatment and other growth factors. The present review provides an outlook on the role of NGF in the prophylaxis and treatment of diabetic foot ulcers. PMID:22928161

  5. ISCHEMIC CENTRAL RETINAL VEIN OCCLUSION IN THE ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR ERA.

    PubMed

    Tam, Emily K; Golchet, Pamela; Yung, Madeline; DeCroos, Francis C; Spirn, Marc; Lehmann-Clarke, Lydia; Ambresin, Aude; Tsui, Irena

    2018-02-01

    Anti-vascular endothelial growth factor therapy has improved the prognosis for patients with central retinal vein occlusion (CRVO). However, most studies published to date exclude ischemic CRVO. The purpose of this study was to describe the outcome in eyes with ischemic CRVO treated with anti-vascular endothelial growth factor therapy. Thirty-seven patients with ischemic CRVO from 3 centers were followed for at least 6 months. Data on patient demographic, vision status, and anti-vascular endothelial growth factor treatments were collected. Average number of injections during the study period was 5. Younger age was associated with improved vision (P = 0.006). Patients with improved visual outcomes tended to have macular edema as the primary indication for treatment, whereas patients with worse outcomes tended to have neovascularization as the primary indication for treatment. This study highlights significant variability in the use of anti-vascular endothelial growth factor therapy for ischemic CRVO and underscores that eyes with neovascularization tend to have worse visual outcomes.

  6. Mouse Balb/c3T3 cell mutant with low epidermal growth factor receptor activity: induction of stable anchorage-independent growth by transforming growth factor. beta

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kuratomi, Y.; Ono, M.; Yasutake, C.

    1987-01-01

    A mutant clone (MO-5) was originally isolated as a clone resistant to Na/sup +//K/sup +/ ionophoric antibiotic monensin from mouse Balb/c3T3 cells. MO-5 was found to show low receptor-endocytosis activity for epidermal growth factor (EGF):binding activity for EGF in MO-5 was less than one tenth of that in Balb/c3T3. Anchorage-independent growth of MO-5 was compared to that of Balb/c3T3 when assayed by colony formation capacity in soft agar. Coadministration of EGF and TGF-..beta.. efficiently enhanced anchorage-independent growth of normal rat kidney (NRK) cells, but neither factor alone was competent to promote the anchorage-independent growth. The frequency of colonies appearing inmore » soft agar of MO-5 or Balb/c3T3 was significantly enhanced by TGF-..beta.. while EGF did not further enhance that of MO-5 or Balb/c3T3. Colonies of Balb/c3T3 formed in soft agar in the presence of TGF-..beta.. showed low colony formation capacity in soft agar in the absence of TGF-..beta... Colonies of MO-5 formed by TGF-..beta.. in soft agar, however, showed high colony formation capacity in soft agar in the absence of TGF-..beta... Pretreatment of MO-5 with TGF-..beta.. induced secretion of TGF-..beta..-like activity from the cells, while the treatment of Balb/c3T3 did not induce the secretion of a significant amount of TGF-..beta..-like activity. The loss of EGF-receptor activity in the stable expression and maintenance of the transformed phenotype in MO-5 is discussed.« less

  7. Microvesicles derived from human umbilical cord mesenchymal stem cells facilitate tubular epithelial cell dedifferentiation and growth via hepatocyte growth factor induction.

    PubMed

    Ju, Guan-qun; Cheng, Jun; Zhong, Liang; Wu, Shuai; Zou, Xiang-yu; Zhang, Guang-yuan; Gu, Di; Miao, Shuai; Zhu, Ying-jian; Sun, Jie; Du, Tao

    2015-01-01

    During acute kidney injury (AKI), tubular cell dedifferentiation initiates cell regeneration; hepatocyte growth factor (HGF) is involved in modulating cell dedifferentiation. Mesenchymal stem cell (MSC)-derived microvesicles (MVs) deliver RNA into injured tubular cells and alter their gene expression, thus regenerating these cells. We boldly speculated that MVs might induce HGF synthesis via RNA transfer, thereby facilitating tubular cell dedifferentiation and regeneration. In a rat model of unilateral AKI, the administration of MVs promoted kidney recovery. One of the mechanisms of action is the acceleration of tubular cell dedifferentiation and growth. Both in vivo and in vitro, rat HGF expression in damaged rat tubular cells was greatly enhanced by MV treatment. In addition, human HGF mRNA present in MVs was delivered into rat tubular cells and translated into the HGF protein as another mechanism of HGF induction. RNase treatment abrogated all MV effects. In the in vitro experimental setting, the conditioned medium of MV-treated injured tubular cells, which contains a higher concentration of HGF, strongly stimulated cell dedifferentiation and growth, as well as Erk1/2 signaling activation. Intriguingly, these effects were completely abrogated by either c-Met inhibitor or MEK inhibitor, suggesting that HGF induction is a crucial contributor to the acceleration of cell dedifferentiation and growth. All these findings indicate that MV-induced HGF synthesis in damaged tubular cells via RNA transfer facilitates cell dedifferentiation and growth, which are important regenerative mechanisms.

  8. Emerging growth factor receptor antagonists for the treatment of renal cell carcinoma.

    PubMed

    Zahoor, Haris; Rini, Brian I

    2016-12-01

    The landscape of systemic treatment for metastatic renal cell carcinoma (RCC) has dramatically changed with the introduction of targeted agents including vascular endothelial growth factor (VEGF) inhibitors. Recently, multiple new agents including growth factor receptor antagonists and a checkpoint inhibitor were approved for the treatment of refractory metastatic RCC based on encouraging benefit shown in clinical trials. Areas covered: The background and biological rationale of existing treatment options including a brief discussion of clinical trials which led to their approval, is presented. This is followed by reviewing the limitations of these therapeutic options, medical need to develop new treatments and major goals of ongoing research. We then discuss two recently approved growth factor receptor antagonists i.e. cabozantinib and lenvatinib, and a recently approved checkpoint inhibitor, nivolumab, and issues pertaining to drug development, and future directions in treatment of metastatic RCC. Expert opinion: Recently approved growth factor receptor antagonists have shown encouraging survival benefit but associated drug toxicity is a major issue. Nivolumab, a programmed death 1 (PD-1) checkpoint inhibitor, has similarly shown survival benefit and is well tolerated. With multiple options now available in this patient population, the right sequence of these agents remains to be determined.

  9. The effect of platelet rich fibrin on growth factor levels in urethral repair.

    PubMed

    Soyer, Tutku; Ayva, Şebnem; Boybeyi, Özlem; Aslan, Mustafa Kemal; Çakmak, Murat

    2013-12-01

    Platelet rich fibrin (PRF) is an autologous source of growth factors and promotes wound healing. An experimental study was performed to evaluate the effect of PRF on growth factor levels in urethral repair. Eighteen Wistar albino rats were included in the study. Rats were allocated in three groups (n:6): control (CG), sham (SG), and PRF (PRFG). In SG, a 5 mm vertical incision was performed in the penile urethra and repaired with 10/0 Vicryl® under a microscope. In PRFG, during the urethral repair as described in SG, 1 cc of blood was sampled from each rat and centrifuged for 10 minutes at 2400 rpm. PRF obtained from the centrifugation was placed on the repair site during closure. Penile urethras were sampled 24 hours after PRF application in PRFG and after urethral repair in SG. Transforming growth factor beta receptor (TGF-β-R-CD105), vascular endothelial growth factor (VEGF) and its receptor (VEGF-R), as well as endothelial growth factor receptor (EGFR), were evaluated in subepithelia of the penile skin and urethra. Groups were compared for growth factor levels and growth factor receptor expression with the Kruskal Wallis test. TGF-β-R levels were significantly decreased in SG when compared to CG (p<0.05). In PRFG, TGF-β-R was increased in both subepithelia of penile skin and urethra with respect to SG (p<0.05). When VEGF levels and its receptor expression were compared between SG and PRFG, VEGF levels were found to be increased in penile skin subepithelium, whereas VEGF-R expressions were decreased in urethral subepithelia in PRFG (p<0.05). There was no difference between groups for EGFR levels (p>0.05). Use of PRF after urethral repair increases TGF-β-R and VEGF expressions in urethral tissue. PRF can be considered as an alternative measure to improve the success of urethral repair. © 2013.

  10. Multiple Mechanisms are Responsible for Transactivation of the Epidermal Growth Factor Receptor in Mammary Epithelial Cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rodland, Karin D.; Bollinger, Nikki; Ippolito, Danielle L.

    2008-11-14

    REVIEW ENTIRE DOCUMENT AT: https://pnlweb.pnl.gov/projects/bsd/ERICA%20Manuscripts%20for%20Review/KD%20Rodland%20D7E80/HMEC_transactivation_ms01_15+Figs.pdf ABSTRACT: Using a single nontransformed strain of human mammary epithelial cells, we found that the ability of multiple growth factors and cytokines to induce ERK phosphorylation was dependent on EGFR activity. These included lysophosphatidic acid (LPA), uridine triphosphate, growth hormone, vascular endothelial growth factor, insulin-like growth factor-1 (IGF-1), and tumor necrosis factoralpha. In contrast, hepatocyte growth factor could stimulate ERK phosphorylation independent of EGFR activity...

  11. Nuclear actions of insulin-like growth factor binding protein-3.

    PubMed

    Baxter, Robert C

    2015-09-10

    In addition to its actions outside the cell, cellular uptake and nuclear import of insulin-like growth factor binding protein-3 (IGFBP-3) has been recognized for almost two decades, but knowledge of its nuclear actions has been slow to emerge. IGFBP-3 has a functional nuclear localization signal and interacts with the nuclear transport protein importin-β. Within the nucleus IGFBP-3 appears to have a role in transcriptional regulation. It can bind to the nuclear receptor, retinoid X receptor-α and several of its dimerization partners, including retinoic acid receptor, vitamin D receptor (VDR), and peroxisome proliferator-activated receptor-γ (PPARγ). These interactions modulate the functions of these receptors, for example inhibiting VDR-dependent transcription in osteoblasts and PPARγ-dependent transcription in adipocytes. Nuclear IGFBP-3 can be detected by immunohistochemistry in cancer and other tissues, and its presence in the nucleus has been shown in many cell culture studies to be necessary for its pro-apoptotic effect, which may also involve interaction with the nuclear receptor Nur77, and export from the nucleus. IGFBP-3 is p53-inducible and in response to DNA damage, forms a complex with the epidermal growth factor receptor (EGFR), translocating to the nucleus to interact with DNA-dependent protein kinase. Inhibition of EGFR kinase activity or downregulation of IGFBP-3 can inhibit DNA double strand-break repair by nonhomologous end joining. IGFBP-3 thus has the ability to influence many cell functions through its interactions with intranuclear pathways, but the importance of these interactions in vivo, and their potential to be targeted for therapeutic benefit, require further investigation. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Epidermal growth factor enhances osteogenic differentiation of dental pulp stem cells in vitro.

    PubMed

    Del Angel-Mosqueda, Casiano; Gutiérrez-Puente, Yolanda; López-Lozano, Ada Pricila; Romero-Zavaleta, Ricardo Emmanuel; Mendiola-Jiménez, Andrés; Medina-De la Garza, Carlos Eduardo; Márquez-M, Marcela; De la Garza-Ramos, Myriam Angélica

    2015-09-03

    Epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) play an important role in extracellular matrix mineralization, a complex process required for proper bone regeneration, one of the biggest challenges in dentistry. The purpose of this study was to evaluate the osteogenic potential of EGF and bFGF on dental pulp stem cells (DPSCs). Human DPSCs were isolated using CD105 magnetic microbeads and characterized by flow cytometry. To induce osteoblast differentiation, the cells were cultured in osteogenic medium supplemented with EGF or bFGF at a low concentration. Cell morphology and expression of CD146 and CD10 surface markers were analyzed using fluorescence microscopy. To measure mineralization, an alizarin red S assay was performed and typical markers of osteoblastic phenotype were evaluated by RT-PCR. EGF treatment induced morphological changes and suppression of CD146 and CD10 markers. Additionally, the cells were capable of producing calcium deposits and increasing the mRNA expression to alkaline phosphatase (ALP) and osteocalcin (OCN) in relation to control groups (p < 0.001). However, bFGF treatment showed an inhibitory effect. These data suggests that DPSCs in combination with EGF could be an effective stem cell-based therapy for bone tissue engineering applications in periodontics and oral implantology.

  13. Transforming growth factor beta-3 and environmental factors and cleft lip with/without cleft palate.

    PubMed

    Guo, Zeqiang; Huang, Chengle; Ding, Kaihong; Lin, Jianyan; Gong, Binzhong

    2010-07-01

    To identify the interactions among two loci (C641A and G15572-) of transforming growth factor beta 3 (TGFbeta3), and exposures in pregnancy with cleft lip with/without cleft palate (CL/P), a hospital-based case-control study was conducted. Associations among offspring polymorphisms of TGFbeta3 C641A and G15572-, paternal smoking, paternal high-risk drinking, maternal passive smoking, and maternal multivitamin supplement with CL/P were analyzed by logistic regression analysis, and the results showed that maternal passive smoking exposures and maternal multivitamin use were associated with the risk of CL/P but offspring polymorphisms of TGFbeta3 C641A and G15572-, paternal smoking, and paternal high-risk drinking were not. Interactions among these variables were analyzed using the multifactor dimensionality reduction method, and the results showed that the two-factor model, including maternal passive smoking and TGFbeta3 C641A, among all models evaluated had the best ability to predict CL/P risk with a maximum cross-validation consistency (9/10) and a maximum average testing accuracy (0.5892; p = 0.0010). These findings suggested that maternal passive smoking exposure is a risk factor for CL/P, whereas maternal multivitamin supplement is a protective factor. The polymorphism of TGFbeta3 C641A participates in interaction effect for CL/P with environmental exposures, although the polymorphism was not associated with CL/P in single-locus analysis, and synergistic effect of TGFbeta3 C641A and maternal passive smoking could provide a new tool for identifying high-risk individuals of CL/P and also an additional evidence that CL/P is determined by both genetic and environmental factors.

  14. PLACENTAL GROWTH FACTOR ADMINISTRATION ABOLISHES PLACENTAL ISCHEMIA-INDUCED HYPERTENSION

    PubMed Central

    Spradley, Frank T.; Tan, Adelene Y.; Joo, Woo S.; Daniels, Garrett; Kussie, Paul; Karumanchi, S. Ananth; Granger, Joey P.

    2016-01-01

    Preeclampsia is a pregnancy-specific disorder of new-onset hypertension. Unfortunately, the most effective treatment is early delivery of the fetus and placenta. Placental ischemia appears central to the pathogenesis of preeclampsia as placental ischemia/hypoxia induced in animals by reduced uterine perfusion pressure (RUPP) or in humans stimulates release of hypertensive placental factors into the maternal circulation. The anti-angiogenic factor soluble fms-like tyrosine kinase-1 (sFlt-1), which antagonizes and reduces bioavailable vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), is elevated in RUPP rats and preeclampsia. Although PlGF and VEGF are both natural ligands for sFlt-1, VEGF also has high affinity to VEGFR2 (Flk-1) causing side effects like edema. PlGF is specific for sFlt-1. We tested the hypothesis that PlGF treatment reduces placental ischemia-induced hypertension by antagonizing sFlt-1 without adverse consequences to the mother or fetus. On gestational day 14, rats were randomized to four groups: normal pregnant (NP) or RUPP ± infusion of rhPlGF (180 μg/kg/day; AG31, a purified, recombinant human form of PlGF) for 5 days via intraperitoneal osmotic minipumps. On day 19, mean arterial blood pressure and plasma sFlt-1 were higher and glomerular filtration rate lower in RUPP than NP rats. Infusion of rhPlGF abolished these changes seen with RUPP along with reducing oxidative stress. These data indicate that the increased sFlt-1 and reduced PlGF resulting from placental ischemia contribute to maternal hypertension. Our novel finding that rhPlGF abolishes placental ischemia-induced hypertension, without major adverse consequences, suggests a strong therapeutic potential for this growth factor in preeclampsia. PMID:26831193

  15. 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. 2011 John Wiley & Sons A/S.

  16. Growth factor-induced morphological, physiological and molecular characteristics in cerebral endothelial cells.

    PubMed

    Krizbai, I A; Bauer, H; Amberger, A; Hennig, B; Szabó, H; Fuchs, R; Bauer, H C

    2000-09-01

    The capacity of vascular endothelial cells to modulate their phenotype in response to changes in environmental conditions is one of the most important characteristics of this cell type. Since different growth factors may play an important signalling role in this adaptive process we have investigated the effect of endothelial cell growth factor (ECGF) on morphological, physiological and molecular characteristics of cerebral endothelial cells (CECs). CECs grown in the presence of ECGF and its cofactor heparin exhibit an epithelial-like morphology (type I CECs). Upon removal of growth factors, CECs develop an elongated spindle-like shape (type II CECs) which is accompanied by the reorganization of actin filaments and the induction of alpha-actin expression. Since one of the most important functions of CECs is the creation of a selective diffusion barrier between the blood and the central nervous system (CNS), we have studied the expression of junction-related proteins in both cell types. We have found that removal of growth factors from endothelial cultures leads to the downregulation of cadherin and occludin protein levels. The loss of junctional proteins was accompanied by a significant increase in the migratory activity and an altered protease activity profile of the cells. TGF-beta1 suppressed endothelial migration in all experiments. Our data provide evidence to suggest that particular endothelial functions are largely controlled by the presence of growth factors. The differences in adhesiveness and migration may play a role in important physiological and pathological processes of endothelial cells such as vasculogenesis or tumor progression.

  17. Cycles of Ubiquitination and Deubiquitination Critically Regulate Growth Factor-Mediated Activation of Akt Signaling

    PubMed Central

    Yang, Wei-Lei; Jin, Guoxiang; Li, Chien-Feng; Jeong, Yun Seong; Moten, Asad; Xu, Dazhi; Feng, Zizhen; Chen, Wei; Cai, Zhen; Darnay, Bryant; Gu, Wei; Lin, Hui-Kuan

    2013-01-01

    K63-linked ubiquitination of Akt is a posttranslational modification that plays a critical role in growth factor-mediated membrane recruitment and activation of Akt. Although E3 ligases involved in growth factor-induced Akt ubiquitination have been defined, the deubiquitinating enzyme (DUB) that triggers deubiquitination of Akt and the function of Akt deubiquitination remain largely unclear. Here, we showed that CYLD was a DUB for Akt and suppressed growth factor-mediated Akt ubiquitination and activation. CYLD directly removed ubiquitin moieties on Akt under serum-starved conditions. CYLD dissociated from Akt upon growth factor stimulation, thereby allowing E3 ligases to induce ubiquitination and activation of Akt. CYLD deficiency also promoted cancer cell proliferation, survival, glucose uptake and growth of prostate tumors. Our findings reveal the crucial role of cycles of ubiquitination and deubiquitination of Akt in its membrane recruitment and activation, and further identifies CYLD as a molecular switch for these processes. PMID:23300340

  18. Multiple faces of fibroblast growth factor-23.

    PubMed

    Han, Xiaobin; Quarles, L Darryl

    2016-07-01

    This review examines the role of fibroblast growth factor-23 (FGF-23) in mineral metabolism, innate immunity and adverse cardiovascular outcomes. FGF-23, produced by osteocytes in bone, activates FGFR/α-Klotho (α-Kl) complexes in the kidney. The resulting bone-kidney axis coordinates renal phosphate reabsorption with bone mineralization, and creates a counter-regulatory feedback loop to prevent vitamin D toxicity. FGF-23 acts to counter-regulate the effects of vitamin D on innate immunity and cardiovascular responses. FGF-23 is ectopically expressed along with α-Kl in activated macrophages, creating a proinflammatory paracrine signaling pathway that counters the antiinflammatory actions of vitamin D. FGF-23 also inhibits angiotensin-converting enzyme 2 expression and increases sodium reabsorption in the kidney, leading to hypertension and left ventricular hypertrophy. Finally, FGF-23 is purported to cause adverse cardiac and impair neutrophil responses through activation of FGFRs in the absence of α-Kl. Although secreted forms of α-Kl have FGF-23 independent effects, the possibility of α-Kl independent effects of FGF-23 is controversial and requires additional experimental validation. FGF-23 participates in a bone-kidney axis regulating mineral homeostasis, proinflammatory paracrine macrophage signaling pathways, and in a bone-cardio-renal axis regulating hemodynamics that counteract the effects of vitamin D.

  19. The role of growth factors in maintenance of stemness in bone marrow-derived mesenchymal stem cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eom, Young Woo; Oh, Ji-Eun; Lee, Jong In

    2014-02-28

    Highlights: • Expression of FGF-2, FGF-4, EGF, and HGF decreased during long-term culture of BMSCs. • Loss of growth factors induced autophagy, senescence and decrease of stemness. • FGF-2 increased proliferation potential via AKT and ERK activation in BMSCs. • FGF-2 suppressed LC3-II expression and down-regulated senescence of BMSCs. • HGF was important in maintenance of the differentiation potential of BMSCs. - Abstract: Mesenchymal stem cells (MSCs) are an active topic of research in regenerative medicine due to their ability to secrete a variety of growth factors and cytokines that promote healing of damaged tissues and organs. In addition, thesemore » secreted growth factors and cytokines have been shown to exert an autocrine effect by regulating MSC proliferation and differentiation. We found that expression of EGF, FGF-4 and HGF were down-regulated during serial passage of bone marrow-derived mesenchymal stem cells (BMSCs). Proliferation and differentiation potentials of BMSCs treated with these growth factors for 2 months were evaluated and compared to BMSCs treated with FGF-2, which increased proliferation of BMSCs. FGF-2 and -4 increased proliferation potentials at high levels, about 76- and 26-fold, respectively, for 2 months, while EGF and HGF increased proliferation of BMSCs by less than 2.8-fold. Interestingly, differentiation potential, especially adipogenesis, was maintained only by HGF treatment. Treatment with FGF-2 rapidly induced activation of AKT and later induced ERK activation. The basal level of phosphorylated ERK increased during serial passage of BMSCs treated with FGF-2. The expression of LC3-II, an autophagy marker, was gradually increased and the population of senescent cells was increased dramatically at passage 7 in non-treated controls. But FGF-2 and FGF-4 suppressed LC3-II expression and down-regulated senescent cells during long-term (i.e. 2 month) cultures. Taken together, depletion of growth factors during serial

  20. Vascular endothelial growth factors: A comparison between invertebrates and vertebrates.

    PubMed

    Kipryushina, Yulia O; Yakovlev, Konstantin V; Odintsova, Nelly A

    2015-12-01

    This review aims to summarize recent data concerning the structure and role of the members of the vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor (VEGFR) families in the context of early development, organogenesis and regeneration, with a particular emphasis on the role of these factors in the development of invertebrates. Homologs of VEGF and/or VEGFR have been found in all Eumetazoa, in both Radiata and Bilateria, where they are expressed in the descendants of different germ layers and play a pivotal role in the development of animals with and without a vascular system. VEGF is a well-known angiogenesis regulator, but this factor also control cell migration during neurogenesis and the development of branching organs (the trachea) in invertebrate and vertebrate species. A possible explanation for the origin of Vegf/Vegfr in the animal kingdom and a pathway of Vegf/Vegfr evolution are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Biological properties of human skeletal myoblasts genetically modified to simultaneously overexpress the pro-angiogenic factors vascular endothelial growth factor-A and fibroblast growth factor-4.

    PubMed

    Zimna, A; Janeczek, A; Rozwadowska, N; Fraczek, M; Kucharzewska, P; Rucinski, M; Mietkiewski, T; Kurpisz, M

    2014-04-01

    Myocardial infarction results in cardiomyocyte loss and may eventually lead to cardiac failure. Skeletal myoblast transplantation into the scar area may compensate for this observed cell loss by strengthening the weakened myocardium and inducing myogenesis. Moreover, skeletal myoblasts may serve as potential transgene carriers for the myocardium (i.e., delivering pro-angiogenic factors, which may potentially improve blood perfusion in infarcted heart). We examined the influence of the simultaneous overexpression of two potent pro-angiogenic factors, fibroblast growth factor-4 (FGF-4) and vascular endothelial growth factor (VEGF), on human primary myoblast proliferation, cell cycle, resistance to hypoxic stress conditions and myogenic gene expression, as well as the induction of pro-angiogenic activities. We used a bicistronic plasmid vector encoding two factors introduced via an efficient myoblast electroporation method. The levels of overexpressed proteins were assessed, and their functionality at capillary formation was evaluated. This combined approach led to a high level of non-viral transient overexpression of both pro-angiogenic proteins, which proved to be potent regulators of blood vessel development assayed in capillary formation tests. We demonstrated in in vitro conditions that the transfection of human skeletal myoblasts with both FGF-4 and VEGF did not affect their basic biological properties such as the cell cycle, proliferation or expression of myogenic lineage-specific genes, and the modified cells adapted to oxidative stress conditions. Overall, the results obtained suggest that the applied combined approach with the use of two pro-angiogenic genes overexpressed in skeletal muscle stem cells may be an interesting alternative for the effective therapy of myocardial infarction in animal models and/or prospective clinical trials.

  2. Selenoprotein W controls epidermal growth factor receptor surface expression, activation and degradation via receptor ubiquitination

    USDA-ARS?s Scientific Manuscript database

    Epidermal growth factor (EGF) receptor (EGFR) is the founding member of the ErbB family of growth factor receptors that modulate a complex network of intracellular signaling pathways controlling growth, proliferation and differentiation. Selenoprotein W (SEPW1) is a diet-regulated, highly conserved...

  3. Basic fibroblastic growth factor affects the osteogenic differentiation of dental pulp stem cells in a treatment-dependent manner.

    PubMed

    Qian, J; Jiayuan, W; Wenkai, J; Peina, W; Ansheng, Z; Shukai, S; Shafei, Z; Jun, L; Longxing, N

    2015-07-01

    To determine how basic fibroblastic growth factor (bFGF) affected the osteogenic differentiation of human dental pulp stem cells (DPSCs) in vitro and in vivo. Basic fibroblastic growth factor stimulation of DPSCs was divided into a pre-treatment period and an osteogenic differentiation period. Alizarin red quantification experiments and alkaline phosphatase activity quantification assay were performed to examine the osteogenic differentiation of DPSCs after different bFGF stimulation. Quantification reverse transcription polymerase chain reaction was used to analyze the osteogenic gene expression of DPSCs after different bFGF stimulation. In addition, DPSCs that received the 1 and 2 weeks bFGF pre-treatments as in the in vitro experiments were mineralized for 1 week and seeded into hydroxyapatite/tricalcium phosphate (HA/TCP) pills and subcutaneously transplanted into naked mice for 2 or 3 months. The transplants were removed, sliced and stained using Modified Ponceau Trichrome Stain to observe the formation of mineralized tissue. Basic fibroblastic growth factor stimulation in the osteogenic differentiation period decreased the in vitro osteogenic differentiation ability of DPSCs. One week pre-treatment with bFGF increased the in vitro osteogenic differentiation ability of DPSCs, whereas 2 weeks pre-treatment with bFGF decreased the in vitro osteogenic differentiation ability of DPSCs. The pre-treatment period was vital for the osteogenic differentiation of DPSCs in vitro. The in vivo results were similar to the in vitro results. Basic fibroblastic growth factor affected the osteogenic differentiation of DPSCs in a treatment-dependent manner both in vitro and in vivo. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  4. Arabidopsis WRKY46, WRKY54, and WRKY70 Transcription Factors Are Involved in Brassinosteroid-Regulated Plant Growth and Drought Responses

    PubMed Central

    Chen, Jiani; Nolan, Trevor M.; Zhang, Mingcai; Tong, Hongning; Xin, Peiyong; Chu, Jinfang; Li, Zhaohu

    2017-01-01

    Plant steroid hormones, brassinosteroids (BRs), play important roles in growth and development. BR signaling controls the activities of BRASSINOSTERIOD INSENSITIVE1-EMS-SUPPRESSOR1/BRASSINAZOLE-RESISTANT1 (BES1/BZR1) family transcription factors. Besides the role in promoting growth, BRs are also implicated in plant responses to drought stress. However, the molecular mechanisms by which BRs regulate drought response have just begun to be revealed. The functions of WRKY transcription factors in BR-regulated plant growth have not been established, although their roles in stress responses are well documented. Here, we found that three Arabidopsis thaliana group III WRKY transcription factors, WRKY46, WRKY54, and WRKY70, are involved in both BR-regulated plant growth and drought response as the wrky46 wrky54 wrky70 triple mutant has defects in BR-regulated growth and is more tolerant to drought stress. RNA-sequencing analysis revealed global roles of WRKY46, WRKY54, and WRKY70 in promoting BR-mediated gene expression and inhibiting drought responsive genes. WRKY54 directly interacts with BES1 to cooperatively regulate the expression of target genes. In addition, WRKY54 is phosphorylated and destabilized by GSK3-like kinase BR-INSENSITIVE2, a negative regulator in the BR pathway. Our results therefore establish WRKY46/54/70 as important signaling components that are positively involved in BR-regulated growth and negatively involved in drought responses. PMID:28576847

  5. Expression of basic fibroblast growth factor mRNA in benign prostatic hyperplasia and prostatic carcinoma.

    PubMed

    Mydlo, J H; Michaeli, J; Heston, W D; Fair, W R

    1988-01-01

    In our previous work we demonstrated that prostate-derived growth factor (PrGF) is homologous to basic fibroblast growth factor (bFGF), not acidic fibroblast growth factor (aFGF). Using Northern blot analysis we now show that the messenger RNA for bFGF but not aFGF is expressed in benign prostatic hyperplastic (BPH) tissue as well as in carcinoma of the prostate (CAP). This not only corroborates our previous results, but suggests that PrGF is produced locally and not merely stored in the prostate. The demonstration of local production of bFGF by prostate tissue may indicate that this growth factor plays a role, either alone or in conjunction with other factors, in the etiology of benign hyperplasia or prostatic cancer.

  6. Circulating growth factors data associated with insulin secretagogue use in women with incident breast cancer.

    PubMed

    Wintrob, Zachary A P; Hammel, Jeffrey P; Nimako, George K; Gaile, Dan P; Forrest, Alan; Ceacareanu, Alice C

    2017-04-01

    Oral drugs stimulating insulin production may impact growth factor levels. The data presented shows the relationship between pre-existing insulin secretagogues use, growth factor profiles at the time of breast cancer diagnosis and subsequent cancer outcomes in women diagnosed with breast cancer and type 2 diabetes mellitus. A Pearson correlation analysis evaluating the relationship between growth factors stratified by diabetes pharmacotherapy and controls is also provided.

  7. Steroid hormone and epidermal growth factor receptors in meningiomas.

    PubMed

    Horsfall, D J; Goldsmith, K G; Ricciardelli, C; Skinner, J M; Tilley, W D; Marshall, V R

    1989-11-01

    A prospective study of steroid hormone and epidermal growth factor receptor expression in 57 meningiomas is presented. Scatchard analysis of radioligand binding identified 20% of meningiomas as expressing classical oestrogen receptors (ER) at levels below that normally accepted for positivity, the remainder being negative. ER could not be visualized in any meningioma using immunocytochemistry. Alternatively, 74% of meningiomas demonstrated the presence of progesterone receptors (PR) by Scatchard analysis, the specificity of which could not be attributed to glucocorticoid or androgen receptors. Confirmation of classical PR presence was determined by immunocytochemical staining. The presence of epidermal growth factor receptor (EGFR) was demonstrated in 100% of meningiomas using immunocytochemical staining. These data are reviewed in the context of previously reported results and are discussed in relation to the potential for medical therapy as an adjunct to surgery.

  8. Stem cell- and growth factor-based regenerative therapies for avascular necrosis of the femoral head

    PubMed Central

    2012-01-01

    Avascular necrosis (AVN) of the femoral head is a debilitating disease of multifactorial genesis, predominately affects young patients, and often leads to the development of secondary osteoarthritis. The evolving field of regenerative medicine offers promising treatment strategies using cells, biomaterial scaffolds, and bioactive factors, which might improve clinical outcome. Early stages of AVN with preserved structural integrity of the subchondral plate are accessible to retrograde surgical procedures, such as core decompression to reduce the intraosseous pressure and to induce bone remodeling. The additive application of concentrated bone marrow aspirates, ex vivo expanded mesenchymal stem cells, and osteogenic or angiogenic growth factors (or both) holds great potential to improve bone regeneration. In contrast, advanced stages of AVN with collapsed subchondral bone require an osteochondral reconstruction to preserve the physiological joint function. Analogously to strategies for osteochondral reconstruction in the knee, anterograde surgical techniques, such as osteochondral transplantation (mosaicplasty), matrix-based autologous chondrocyte implantation, or the use of acellular scaffolds alone, might preserve joint function and reduce the need for hip replacement. This review summarizes recent experimental accomplishments and initial clinical findings in the field of regenerative medicine which apply cells, growth factors, and matrices to address the clinical problem of AVN. PMID:22356811

  9. Enhanced Growth and Hepatic Differentiation of Fetal Liver Epithelial Cells through Combinational and Temporal Adjustment of Soluble Factors

    PubMed Central

    Qian, Lichuan; Krause, Diane S.; Saltzman, W. Mark

    2012-01-01

    Fetal liver epithelial cells (FLEC) are valuable for liver cell therapy and tissue engineering, but methods for culture and characterization of these cells are not well developed. This work explores the influence of multiple soluble factors on FLEC, with the long-term goal of developing an optimal culture system to generate functional liver tissue. Our comparative analysis suggests hepatocyte growth factor (HGF) is required throughout the culture period. In the presence of HGF, addition of oncostatin M (OSM) at culture initiation results in concurrent growth and maturation, while constant presence of protective agents like ascorbic acid enhances cell survival. Study observations led to the development of a culture medium that provided optimal growth and hepatic differentiation conditions. FLEC expansion was observed to be ~2 fold of that under standard conditions, albumin secretion rate was 2 – 3 times greater than maximal values obtained with other media, and the highest level of glycogen accumulation among all conditions was observed with the developed medium. Our findings serve to advance culture methods for liver progenitors in cell therapy and tissue engineering applications. PMID:21922669

  10. Up-Regulation of Bcl-xl by Hepatocyte Growth Factor in Human Mesothelioma Cells Involves ETS Transcription Factors

    PubMed Central

    Cao, Xiaobo; Littlejohn, James; Rodarte, Charles; Zhang, Lidong; Martino, Benjamin; Rascoe, Philip; Hamid, Kamran; Jupiter, Daniel; Smythe, W. Roy

    2009-01-01

    Bcl-xl and the hepatocyte growth factor (HGF) receptor c-Met are both highly expressed in mesotheliomas, where they protect cells from apoptosis and can confer resistance to conventional therapeutic agents. In our current study, we investigate a model for the transcriptional control of Bcl-xl that involves ETS transcription factors and the HGF/Met axis. In addition, the effects of activated c-Met on the phosphorylation of the ETS family transcriptional factors were examined. The transient expression of ETS-2 and PU.1 cDNAs in mesothelioma cell lines resulted in an increase in the promoter activity of Bcl-xl and consequently in its mRNA and protein expression levels, whereas the transcriptional repressor Tel suppressed Bcl-xl transcription. The activation of the HGF/Met axis led to rapid phosphorylation of ETS family transcription factors in mesothelioma cells through the mitogen-activated protein kinase pathway and via nuclear accumulation of ETS-2 and PU.1. A chromatin immunoprecipitation assay further demonstrated that the activation of c-Met enhanced the binding of ETS transcriptional factors to the Bcl-x promoter. Finally, we determined the Bcl-xl and phosphorylated c-Met expression levels in mesothelioma patient samples; these data suggest a strong correlation between Bcl-xl and phosphorylated c-Met levels. Taken together, these findings support a role for c-Met as an inhibitor of apoptosis and an activator of Bcl-xl. PMID:19834061

  11. Synergistic apoptosis in head and neck squamous cell carcinoma cells by co-inhibition of insulin-like growth factor-1 receptor signaling and compensatory signaling pathways.

    PubMed

    Axelrod, Mark J; Mendez, Rolando E; Khalil, Ashraf; Leimgruber, Stephanie S; Sharlow, Elizabeth R; Capaldo, Brian; Conaway, Mark; Gioeli, Daniel G; Weber, Michael J; Jameson, Mark J

    2015-12-01

    In head and neck squamous cell carcinoma (HNSCC), resistance to single-agent targeted therapy may be overcome by co-targeting of compensatory signaling pathways. A targeted drug screen with 120 combinations was used on 9 HNSCC cell lines. Multiple novel drug combinations demonstrated synergistic growth inhibition. Combining the insulin-like growth factor-1 receptor (IGF-1R) inhibitor, BMS754807, with either the human epidermal growth factor receptor (HER)-family inhibitor, BMS599626, or the Src-family kinase inhibitor, dasatinib, resulted in substantial synergy and growth inhibition. Depending on the cell line, these combinations induced synergistic or additive apoptosis; when synergistic apoptosis was observed, AKT phosphorylation was inhibited to a greater extent than either drug alone. Conversely, when additive apoptosis occurred, AKT phosphorylation was not reduced by the drug combination. Combined IGF-1R/HER family and IGF-1R/Src family inhibition may have therapeutic potential in HNSCC. AKT may be a node of convergence between IGF-1R signaling and pathways that compensate for IGF-1R inhibition. © 2015 Wiley Periodicals, Inc.

  12. 3D axon growth by exogenous electrical stimulus and soluble factors.

    PubMed

    Tang-Schomer, Min D

    2018-01-01

    Axon growth and alignment are fundamental processes during nervous system development and neural regeneration after injury. The present study investigates the effects of exogenous stimulus of electrical signals and soluble factors on axon 3D growth, using a silk protein material-based 3D brain tissue model. Electrical stimulus was delivered via embedded gold wires positioned at the interface of the scaffold region and the center matrix gel-filled region, spanning the axon growth area. This setup delivered applied electrical field directly to growing axons, and the effects were compared to micro-needle assisted local delivery of soluble factors of extracellular (ECM) components and neurotrophins. Dissociated rat cortical neurons were exposed to an alternating field of 80 mV/mm at 0.5 Hz to 2 kHz or soluble factors for up to 4 days, and evaluated by of β III-tubulin immunostaining, confocal imaging and 3D neurite tracing. 0.5-20 Hz were found to promote axon growth, with 2 Hz producing the biggest effect of ∼30% axon length increase compared to control cultures. Delivery of ECM components of laminin and fibronectin resulted significantly greater axon initial length increases compared to neurotrophic factors, such as BDNF, GDNF, NGF and NT3 (all at 1 μM). Though axon lengths under 2 Hz stimulation and LN or FN exposure were statistically similar, significant AC-induced axon alignment was found under all frequencies tested. The effects included perpendicular orientation of axons trespassing an electrode, large populations of aligned axon tracts in parallel to the field direction with a few perpendicularly aligned along the middle point of the EF. These findings are consistent with the hypothesis that an electrode in AC field could act as an alternating cathode that attracts the growing tip of the axon. These results demonstrate the use of alternating electric field stimulation to direct axon 3D length growth and orientation. Our study provides basis

  13. A combined model of human erythropoiesis and granulopoiesis under growth factor and chemotherapy treatment

    PubMed Central

    2014-01-01

    Background Haematotoxicity of conventional chemotherapies often results in delays of treatment or reduction of chemotherapy dose. To ameliorate these side-effects, patients are routinely treated with blood transfusions or haematopoietic growth factors such as erythropoietin (EPO) or granulocyte colony-stimulating factor (G-CSF). For the latter ones, pharmaceutical derivatives are available, which differ in absorption kinetics, pharmacokinetic and -dynamic properties. Due to the complex interaction of cytotoxic effects of chemotherapy and the stimulating effects of different growth factor derivatives, optimal treatment is a non-trivial task. In the past, we developed mathematical models of thrombopoiesis, granulopoiesis and erythropoiesis under chemotherapy and growth-factor applications which can be used to perform clinically relevant predictions regarding the feasibility of chemotherapy schedules and cytopenia prophylaxis with haematopoietic growth factors. However, interactions of lineages and growth-factors were ignored so far. Results To close this gap, we constructed a hybrid model of human granulopoiesis and erythropoiesis under conventional chemotherapy, G-CSF and EPO applications. This was achieved by combining our single lineage models of human erythropoiesis and granulopoiesis with a common stem cell model. G-CSF effects on erythropoiesis were also implemented. Pharmacodynamic models are based on ordinary differential equations describing proliferation and maturation of haematopoietic cells. The system is regulated by feedback loops partly mediated by endogenous and exogenous EPO and G-CSF. Chemotherapy is modelled by depletion of cells. Unknown model parameters were determined by fitting the model predictions to time series data of blood counts and cytokine profiles. Data were extracted from literature or received from cooperating clinical study groups. Our model explains dynamics of mature blood cells and cytokines after growth-factor applications in

  14. Cardiac Regeneration using Growth Factors: Advances and Challenges.

    PubMed

    Rebouças, Juliana de Souza; Santos-Magalhães, Nereide Stela; Formiga, Fabio Rocha

    2016-09-01

    Myocardial infarction is the most significant manifestation of ischemic heart disease and is associated with high morbidity and mortality. Novel strategies targeting at regenerating the injured myocardium have been investigated, including gene therapy, cell therapy, and the use of growth factors. Growth factor therapy has aroused interest in cardiovascular medicine because of the regeneration mechanisms induced by these biomolecules, including angiogenesis, extracellular matrix remodeling, cardiomyocyte proliferation, stem-cell recruitment, and others. Together, these mechanisms promote myocardial repair and improvement of the cardiac function. This review aims to address the strategic role of growth factor therapy in cardiac regeneration, considering its innovative and multifactorial character in myocardial repair after ischemic injury. Different issues will be discussed, with emphasis on the regeneration mechanisms as a potential therapeutic resource mediated by growth factors, and the challenges to make these proteins therapeutically viable in the field of cardiology and regenerative medicine. Resumo O infarto do miocárdio representa a manifestação mais significativa da cardiopatia isquêmica e está associado a elevada morbimortalidade. Novas estratégias vêm sendo investigadas com o intuito de regenerar o miocárdio lesionado, incluindo a terapia gênica, a terapia celular e a utilização de fatores de crescimento. A terapia com fatores de crescimento despertou interesse em medicina cardiovascular, devido aos mecanismos de regeneração induzidos por essas biomoléculas, incluindo angiogênese, remodelamento da matriz extracelular, proliferação de cardiomiócitos e recrutamento de células-tronco, dentre outros. Em conjunto, tais mecanismos promovem a reparação do miocárdio e a melhora da função cardíaca. Esta revisão pretende abordar o papel estratégico da terapia, com fatores de crescimento, para a regeneração cardíaca, considerando seu car

  15. GP88 (PC-Cell Derived Growth Factor, progranulin) stimulates proliferation and confers letrozole resistance to aromatase overexpressing breast cancer cells

    PubMed Central

    2011-01-01

    Background Aromatase inhibitors (AI) that inhibit breast cancer cell growth by blocking estrogen synthesis have become the treatment of choice for post-menopausal women with estrogen receptor positive (ER+) breast cancer. However, some patients display de novo or acquired resistance to AI. Interactions between estrogen and growth factor signaling pathways have been identified in estrogen-responsive cells as one possible reason for acquisition of resistance. Our laboratory has characterized an autocrine growth factor overexpressed in invasive ductal carcinoma named PC-Cell Derived Growth Factor (GP88), also known as progranulin. In the present study, we investigated the role GP88 on the acquisition of resistance to letrozole in ER+ breast cancer cells Methods We used two aromatase overexpressing human breast cancer cell lines MCF-7-CA cells and AC1 cells and their letrozole resistant counterparts as study models. Effect of stimulating or inhibiting GP88 expression on proliferation, anchorage-independent growth, survival and letrozole responsiveness was examined. Results GP88 induced cell proliferation and conferred letrozole resistance in a time- and dose-dependent fashion. Conversely, naturally letrozole resistant breast cancer cells displayed a 10-fold increase in GP88 expression when compared to letrozole sensitive cells. GP88 overexpression, or exogenous addition blocked the inhibitory effect of letrozole on proliferation, and stimulated survival and soft agar colony formation. In letrozole resistant cells, silencing GP88 by siRNA inhibited cell proliferation and restored their sensitivity to letrozole. Conclusion Our findings provide information on the role of an alternate growth and survival factor on the acquisition of aromatase inhibitor resistance in ER+ breast cancer. PMID:21658239

  16. Subglottic injury, gastric juice, corticosteroids, and peptide growth factors in a porcine model.

    PubMed

    Yellon, R F; Szeremeta, W; Grandis, J R; Diguisseppe, P; Dickman, P S

    1998-06-01

    To study the effects of mucosal injury, gastric juice, and corticosteroids and to determine the presence of peptide growth factors in the subglottic mucosa in a porcine model. Prospective cohort animal study. In this model of subglottic injury, five groups (n = 5 each) of piglets were used. Injury was induced by electrocautery (acute), electrocautery plus repeated saline application (chronic), electrocautery plus repeated gastric juice application (chronic plus gastric juice), or repeated gastric juice application (gastric). Control piglets had normal saline applied repeatedly. Histopathologic findings for the gastric juice group included basal cell hyperplasia (80%), squamous metaplasia (80%), and mucosal ulceration (40%). Control piglets showed squamous metaplasia (80%) but no basilar hyperplasia or ulceration. Immunohistochemistry detected peptide growth factors and epidermal growth factor receptor (EGFR) in all groups. Decreased staining was most frequent in the acute injury group. Quantitative reverse transcriptase polymerase chain reaction (RT-PCR) documented lower expression of EGFR in the gastric juice group (P = .01). These findings suggest that peptide growth factors and EGFR are part of normal subglottic mucosal turnover. Noxious stimuli decrease production of these factors. Gastric juice had adverse effects documented by histopathology and molecular techniques.

  17. Prohormone convertase and autocrine growth factor mRNAs are coexpressed in small cell lung carcinoma.

    PubMed

    Rounseville, M P; Davis, T P

    2000-08-01

    A hallmark of small cell lung carcinoma (SCLC) is the expression of autocrine growth factors such as neurotensin and gastrin-releasing peptide, which bind to cellular receptors and stimulate cell division. The biological activity of autocrine growth factors requires the concurrent expression of prohormone convertases that cleave the growth factors to their active form, suggesting the expression of these genes is linked in SCLCs. RNase protection assays were used to detect the expression of autocrine growth factor and prohormone convertase mRNAs in a panel of lung cancer cell lines. These mRNAs are coexpressed in SCLC and lung carcinoid cell lines, but not in normal lung epithelium or in non-small cell lung cancers. These findings, together with earlier results from our laboratory, suggest the expression of prohormone convertases has an important role in the development and maintenance of the SCLC phenotype and that autocrine growth factor and prohormone convertase genes respond to a common transcriptional activator in SCLC.

  18. Selective role for RGS12 as a Ras/Raf/MEK scaffold in nerve growth factor-mediated differentiation

    PubMed Central

    Willard, Melinda D; Willard, Francis S; Li, Xiaoyan; Cappell, Steven D; Snider, William D; Siderovski, David P

    2007-01-01

    Regulator of G-protein signaling (RGS) proteins accelerate GTP hydrolysis by heterotrimeric G-protein α subunits and thus inhibit signaling by many G protein-coupled receptors. Several RGS proteins have a multidomain architecture that adds further complexity to their roles in cell signaling in addition to their GTPase-accelerating activity. RGS12 contains a tandem repeat of Ras-binding domains but, to date, the role of this protein in Ras-mediated signal transduction has not been reported. Here, we show that RGS12 associates with the nerve growth factor (NGF) receptor tyrosine kinase TrkA, activated H-Ras, B-Raf, and MEK2 and facilitates their coordinated signaling to prolonged ERK activation. RGS12 is required for NGF-mediated neurite outgrowth of PC12 cells, but not outgrowth stimulated by basic fibroblast growth factor. siRNA-mediated knockdown of RGS12 expression also inhibits NGF-induced axonal growth in dissociated cultures of primary dorsal root ganglia neurons. These data suggest that RGS12 may play a critical, and receptor-selective, role in coordinating Ras-dependent signals that are required for promoting and/or maintaining neuronal differentiation. PMID:17380122

  19. Synergistic inhibition with a dual epidermal growth factor receptor/HER-2/neu tyrosine kinase inhibitor and a disintegrin and metalloprotease inhibitor.

    PubMed

    Witters, Lois; Scherle, Peggy; Friedman, Steven; Fridman, Jordan; Caulder, Eian; Newton, Robert; Lipton, Allan

    2008-09-01

    The ErbB family of receptors is overexpressed in numerous human tumors. Overexpression correlates with poor prognosis and resistance to therapy. Use of ErbB-specific antibodies to the receptors (Herceptin or Erbitux) or ErbB-specific small-molecule inhibitors of the receptor tyrosine kinase activity (Iressa or Tarceva) has shown clinical efficacy in several solid tumors. An alternative method of affecting ErbB-initiated tumor growth and survival is to block sheddase activity. Sheddase activity is responsible for cleavage of multiple ErbB ligands and receptors, a necessary step in availability of the soluble, active form of the ligand and a constitutively activated ligand-independent receptor. This sheddase activity is attributed to the ADAM (a disintegrin and metalloprotease) family of proteins. ADAM 10 is the main sheddase of epidermal growth factor (EGF) and HER-2/neu cleavage, whereas ADAM17 is required for cleavage of additional EGF receptor (EGFR) ligands (transforming growth factor-alpha, amphiregulin, heregulin, heparin binding EGF-like ligand). This study has shown that addition of INCB3619, a potent inhibitor of ADAM10 and ADAM17, reduces in vitro HER-2/neu and amphiregulin shedding, confirming that it interferes with both HER-2/neu and EGFR ligand cleavage. Combining INCB3619 with a lapatinib-like dual inhibitor of EGFR and HER-2/neu kinases resulted in synergistic growth inhibition in MCF-7 and HER-2/neu-transfected MCF-7 human breast cancer cells. Combining the INCB7839 second-generation sheddase inhibitor with lapatinib prevented the growth of HER-2/neu-positive BT474-SC1 human breast cancer xenografts in vivo. These results suggest that there may be an additional clinical benefit of combining agents that target the ErbB pathways at multiple points.

  20. All about running: synaptic plasticity, growth factors and adult hippocampal neurogenesis.

    PubMed

    Vivar, Carmen; Potter, Michelle C; van Praag, Henriette

    2013-01-01

    Accumulating evidence from animal and human research shows exercise benefits learning and memory, which may reduce the risk of neurodegenerative diseases, and could delay age-related cognitive decline. Exercise-induced improvements in learning and memory are correlated with enhanced adult hippocampal neurogenesis and increased activity-dependent synaptic plasticity. In this present chapter we will highlight the effects of physical activity on cognition in rodents, as well as on dentate gyrus (DG) neurogenesis, synaptic plasticity, spine density, neurotransmission and growth factors, in particular brain-derived nerve growth factor (BDNF).

  1. Platelet-rich plasma preparation for regenerative medicine: optimization and quantification of cytokines and growth factors.

    PubMed

    Amable, Paola Romina; Carias, Rosana Bizon Vieira; Teixeira, Marcus Vinicius Telles; da Cruz Pacheco, Italo; Corrêa do Amaral, Ronaldo José Farias; Granjeiro, José Mauro; Borojevic, Radovan

    2013-06-07

    Platelet-rich plasma (PRP) is nowadays widely applied in different clinical scenarios, such as orthopedics, ophthalmology and healing therapies, as a growth factor pool for improving tissue regeneration. Studies into its clinical efficiency are not conclusive and one of the main reasons for this is that different PRP preparations are used, eliciting different responses that cannot be compared. Platelet quantification and the growth factor content definition must be defined in order to understand molecular mechanisms behind PRP regenerative strength. Standardization of PRP preparations is thus urgently needed. PRP was prepared by centrifugation varying the relative centrifugal force, temperature, and time. Having quantified platelet recovery and yield, the two-step procedure that rendered the highest output was chosen and further analyzed. Cytokine content was determined in different fractions obtained throughout the whole centrifugation procedure. Our method showed reproducibility when applied to different blood donors. We recovered 46.9 to 69.5% of total initial platelets and the procedure resulted in a 5.4-fold to 7.3-fold increase in platelet concentration (1.4 × 10(6) to 1.9 × 10(6) platelets/μl). Platelets were highly purified, because only <0.3% from the initial red blood cells and leukocytes was present in the final PRP preparation. We also quantified growth factors, cytokines and chemokines secreted by the concentrated platelets after activation with calcium and calcium/thrombin. High concentrations of platelet-derived growth factor, endothelial growth factor and transforming growth factor (TGF) were secreted, together with the anti-inflammatory and proinflammatory cytokines interleukin (IL)-4, IL-8, IL-13, IL-17, tumor necrosis factor (TNF)-α and interferon (IFN)-α. No cytokines were secreted before platelet activation. TGF-β3 and IFNγ were not detected in any studied fraction. Clots obtained after platelet coagulation retained a high concentration

  2. Nerve Growth Factor: Early Studies And Recent Clinical Trials.

    PubMed

    Rocco, Maria Luisa; Soligo, Marzia; Manni, Luigi; Aloe, Luigi

    2018-04-11

    Since its discovery, nerve growth factor (NGF) has long occupied a critical role in developmental and adult neurobiology for its many important regulatory functions on the survival, growth and differentiation of nerve cells in the peripheral and central nervous system. NGF is the first discovered member of a family of neurotrophic factors, collectively indicated as neurotrophins, (which include brain-derived neurotrophic factor, neurotrophin-3 and neurotrophin 4/5). NGF was discovered for its action on the survival and differentiation of selected populations of peripheral neurons. Since then, an enormous number of basic and human studies were undertaken to explore the role of purified NGF to prevent the death of NGF-receptive cells. These studies revealed that NGF possesses important therapeutic properties, after topical administration, on human cutaneous pressure ulcer, corneal ulcers, glaucoma, retinal maculopathy, Retinitis Pigmentosa and in pediatric optic gliomas and brain traumas. The aim of this review is to present our previous, recent and ongoing clinical studies on the therapeutic properties of NGF. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Comparison between tocotrienol and omeprazole on gastric growth factors in stress-exposed rats.

    PubMed

    Nur Azlina, Mohd Fahami; Qodriyah, Hj Mohd Saad; Chua, Kien Hui; Kamisah, Yusof

    2017-08-28

    To investigate and compare the effects of tocotrienol and omeprazole on gastric growth factors in rats exposed to water-immersion restraint stress (WIRS). Twenty-eight male Wistar rats were randomly assigned to four groups of seven rats. The two control groups were administered vitamin-free palm oil (vehicle) and the two treatment groups were given omeprazole (20 mg/kg) or tocotrienol (60 mg/kg) by oral gavage. After 28 d of treatment, rats from one control group and both treated groups were subjected to WIRS one time for 3.5 h. Gastric lesions were measured and gastric tissues were obtained to measure vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and transforming growth factor-alpha (TGF-α) mRNA expression. Rats exposed to WIRS for 3.5 h demonstrated the presence of considerable ulcers in the form of gastric erosion. The lesion index in the stressed control (S) group was increased ( P < 0.001) compared to the tocotrienol treated and omeprazole treated groups. Stress led to a decrease in gastric VEGF ( P < 0.001), bFGF ( P < 0.001) and TGF-α ( P < 0.001) mRNA levels and caused an increase in EGF mRNA ( P < 0.001) that was statistically significant compared to the non-stressed control group. Although both treatment agents exerted similar ulcer reducing ability, only treatment with tocotrienol led to increased expression of VEGF ( P = 0.008), bFGF ( P = 0.001) and TGF-α ( P = 0.002) mRNA. Tocotrienol provides gastroprotective effects in WIRS-induced ulcers. Compared to omeprazole, tocotrienol exerts a similar protective effect, albeit through multiple mechanisms of protection, particularly through up-regulation of growth factors that assist in repair of gastric tissue injuries.

  4. Platelet-derived growth factor predicts prolonged relapse-free period in multiple sclerosis.

    PubMed

    Stampanoni Bassi, Mario; Iezzi, Ennio; Marfia, Girolama A; Simonelli, Ilaria; Musella, Alessandra; Mandolesi, Georgia; Fresegna, Diego; Pasqualetti, Patrizio; Furlan, Roberto; Finardi, Annamaria; Mataluni, Giorgia; Landi, Doriana; Gilio, Luana; Centonze, Diego; Buttari, Fabio

    2018-04-14

    In the early phases of relapsing-remitting multiple sclerosis (RR-MS), a clear correlation between brain lesion load and clinical disability is often lacking, originating the so-called clinico-radiological paradox. Different factors may contribute to such discrepancy. In particular, synaptic plasticity may reduce the clinical expression of brain damage producing enduring enhancement of synaptic strength largely dependent on neurotrophin-induced protein synthesis. Cytokines released by the immune cells during acute inflammation can alter synaptic transmission and plasticity possibly influencing the clinical course of MS. In addition, immune cells may promote brain repair during the post-acute phases, by secreting different growth factors involved in neuronal and oligodendroglial cell survival. Platelet-derived growth factor (PDGF) is a neurotrophic factor that could be particularly involved in clinical recovery. Indeed, PDGF promotes long-term potentiation of synaptic activity in vitro and in MS and could therefore represent a key factor improving the clinical compensation of new brain lesions. The aim of the present study is to explore whether cerebrospinal fluid (CSF) PDGF concentrations at the time of diagnosis may influence the clinical course of RR-MS. At the time of diagnosis, we measured in 100 consecutive early MS patients the CSF concentrations of PDGF, of the main pro- and anti-inflammatory cytokines, and of reliable markers of neuronal damage. Clinical and radiological parameters of disease activity were prospectively collected during follow-up. CSF PDGF levels were positively correlated with prolonged relapse-free survival. Radiological markers of disease activity, biochemical markers of neuronal damage, and clinical parameters of disease progression were instead not influenced by PDGF concentrations. Higher CSF PDGF levels were associated with an anti-inflammatory milieu within the central nervous system. Our results suggest that PDGF could promote a

  5. Preclinical and clinical studies on the use of growth factors for bone repair: a systematic review.

    PubMed

    Fisher, Daniel Mark; Wong, James Min-Leong; Crowley, Conor; Khan, Wasim S

    2013-05-01

    Bone healing is a complex process. Whilst the majority of fractures heal with conventional treatment, open fractures, large bone defects and non unions still provide great challenges to Orthopaedic Surgeons. Whilst autologous bone graft is seen as the gold standard, the use of growth factors is a growing area of research to find an effective alternative with lower side effects such as donor site morbidity and the finite amount available. This systematic review aims to summarize the pre clinical in-vivo studies and examine the clinical studies on the use of growth factors in bone healing. Databases: PubMed, Medline, OVID, and Cochrane library. The following key words and search terms were used: Growth Factors, Bone Healing, Bone Morphogenic Protein, Transforming Growth Factor Beta, Insulin Like Growth Factor, Platelet Derived Growth Factor, Fracture. All articles were screened based on title with abstracts and full text articles reviewed as appropriate. Reference lists were reviewed from relevant articles to ensure comprehensive and systematic review. Three tables of studies were constructed focussing on Bone Morphogenic Proteins, Platelet Rich Plasma and Growth Factors and Tissue Engineering. Bone Morphogenic Proteins and Platelet Rich Plasma, which contains multiple growth factors, have been shown in preclinical and clinical trials to be an effective alternative to autologous bone graft. Bone Morphogenic Proteins have been shown to be effective in fracture non union, and in open tibial fractures. Platelet Rich Plasma has shown promise in preclinical trials and some small clinical trials, however numbers are limited. Bone Morphogenic Proteins have been shown to be superior to Platelet Rich Protein in one trial. Combining these growth factors with tissue engineering techniques is the focus of ongoing research, and through further clinical trials the most effective techniques for enhancing bone healing will be revealed.

  6. Differential effects of caffeine on hair shaft elongation, matrix and outer root sheath keratinocyte proliferation, and transforming growth factor-β2/insulin-like growth factor-1-mediated regulation of the hair cycle in male and female human hair follicles in vitro.

    PubMed

    Fischer, T W; Herczeg-Lisztes, E; Funk, W; Zillikens, D; Bíró, T; Paus, R

    2014-11-01

    Caffeine reportedly counteracts the suppression of hair shaft production by testosterone in organ-cultured male human hair follicles (HFs). We aimed to investigate the impact of caffeine (i) on additional key hair growth parameters, (ii) on major hair growth regulatory factors and (iii) on male vs. female HFs in the presence of testosterone. Microdissected male and female human scalp HFs were treated in serum-free organ culture for 120 h with testosterone alone (0·5 μg mL(-1)) or in combination with caffeine (0·005-0·0005%). The following effects on hair shaft elongation were evaluated by quantitative (immuno)histomorphometry: HF cycling (anagen-catagen transition); hair matrix keratinocyte proliferation; expression of a key catagen inducer, transforming growth factor (TGF)-β2; and expression of the anagen-prolonging insulin-like growth factor (IGF)-1. Caffeine effects were further investigated in human outer root sheath keratinocytes (ORSKs). Caffeine enhanced hair shaft elongation, prolonged anagen duration and stimulated hair matrix keratinocyte proliferation. Female HFs showed higher sensitivity to caffeine than male HFs. Caffeine counteracted testosterone-enhanced TGF-β2 protein expression in male HFs. In female HFs, testosterone failed to induce TGF-β2 expression, while caffeine reduced it. In male and female HFs, caffeine enhanced IGF-1 protein expression. In ORSKs, caffeine stimulated cell proliferation, inhibited apoptosis/necrosis, and upregulated IGF-1 gene expression and protein secretion, while TGF-β2 protein secretion was downregulated. This study reveals new growth-promoting effects of caffeine on human hair follicles in subjects of both sexes at different levels (molecular, cellular and organ). © 2014 British Association of Dermatologists.

  7. Partial characterization of a putative new growth factor present in pathological human vitreous.

    PubMed

    Pombo, C; Bokser, L; Casabiell, X; Zugaza, J; Capeans, M; Salorio, M; Casanueva, F

    1996-03-01

    Several growth factors have been implicated in the development of proliferative eye diseases, and some of those are present in human vitreous (HV). The effects of HV on cellular responses which modulate proliferative cell processes were studied. This study describes the partial characterization of a vitreous factor activity which does not correspond to any of the previously reported growth factors in pathological HV. Vitreous humour was obtained from medical vitrectomies, from patients with PDR and PVR. The biological activity of the vitreous factor was determined by its ability to increase cytosolic calcium concentration ([Ca2+]i), increase production of inositol phosphates, and induce cell proliferation in the cell line EGFR T17. In some experiments other cell lines, such as NIH 3T3, 3T3-L1, FRTL5, A431, PC12, Y79, and GH3, were also employed. Measurement of [Ca2+]i in cell suspensions was performed using the fluorescent Ca2+ indicator fura-2. The activity of the factor present in HV was compared with other growth factors by means of: (a) [Ca2+]i mobilization pattern, (b) sequential homologous and heterologous desensitization of receptors, (c) effects of phorbol esters on their action, and (d) inactivation after treatment with different proteolytic enzymes. The HV-induced cell proliferation and increases in [Ca2+]i concentration were characterized by a peculiar time pattern. The different approaches used ruled out its identity with PDGF, bFGF, EGF, TGF-beta, IGFs, TNF-alpha, NGF, and other compounds such as ATP, angiotensin I, and bradykinin. Vitreous factor actions are mediated by specific receptors apparently regulated by PKC. This factor is able to induce [Ca2+]i mobilization in most of the cell lines studied, indicating that its effects are not tissue specific. These results suggest the presence of a growth factor activity in pathological HV which may be due to the presence of an undescribed growth factor in the eye.

  8. Role of insulin-like growth factor-I in the regulation of skeletal muscle adaptation to increased loading

    NASA Technical Reports Server (NTRS)

    Adams, G. R.

    1998-01-01

    Adaptations in muscle mass stimulated by changes in muscle loading state entail alternations in the synthesis and degradation of myofiber proteins and the modulation of myonuclear number such that the ratio between the number of myonuclei and the size of the myofibers remains relatively constant. As depicted schematically in Figure 2.6, the literature regarding the role of IGF-in mediating muscle adaptation to alterations in loading state suggests the following conclusions: During periods of increased loading, myofibers upregulate the expression and secretion of IGF-I. Acting as an autocrine and/or paracrine growth factor, IGF-I stimulates myofiber anabolic processes. Acting as a paracrine growth factor, IGF-I also stimulates adjacent satellite cells to enter the cell cycle and proliferate. Continued myofiber production of IGF-I stimulates some satellite cells to differentiate and then fuse with myofibers, thus providing additional myonuclei in order to maintain or reestablish the myonucleus to myofiber size ratios of the enlarged myofibers.

  9. Diagnostic Usefulness of Insulin-Like Growth Factor 1 and Insulin-Like Growth Factor Binding Protein 3 in Children with Suspected Pituitary Dwarfism.

    PubMed

    Zelazowska-Rutkowska, Beata; Trusiak, Marta; Bossowski, Artur; Cylwik, Bogdan

    2018-05-01

    Pituitary dwarfism (also known as short stature) is a medical condition in which the pituitary gland does not produce enough growth hormone (GH). To confirm the diagnosis of growth hormone deficiency the overnight profile of GH secretion and GH provocative tests are usually performed; however, due to wide GH fluctuations throughout the day and night and the invasiveness of stimulation tests, their clinical utility is limited. Therefore, screening for IGF-1 (insulin-like growth factor 1) and IGFBP-3 (insulin-like growth factor binding protein type 3) is proposed, suggesting that these tests provide a more accurate reflection of the mean plasma GH level, although the results of these tests are still problematic. In this context, the aim of this study was to assess the diagnostic usefulness of IGF-1 and IGFBP-3 in children with suspected pituitary dwarfism. Studies were carried out in 127 children with abnormal growth and low spontaneous 24-hour plasma GH profiles and abnormal results of GH stimulation tests. Fasting serum IGF-1 and IGFBP-3 were determined by chemiluminescent quantitative measurement using the IMMULITE 1000 IGF-1 and IGFBP-3 kits (Siemens Healthcare Diagnostics, United Kingdom) on the IMMULITE 1000 analyzer (Siemens Healthcare Diagnostics, USA). Results were compared to the normal range by children's age. Mean serum IGF-1 concentrations were within the lower normal range (41.7% cases), and 58.3% results were below the normal reference range in the study group. The average serum IGFBP-3 levels were within the lower normal range. We conclude that IGF-1 test can be a useful tool in the diagnosis of pituitary dwarfism in children suspected of this condition, but due to relatively poor sensitivity the testing cannot be performed alone, but in combination with other tests. The IGFBP-3 test is not useful for the diagnosis of this disease.

  10. Insulin-Like Growth Factor-1 Deficiency and Cirrhosis Establishment

    PubMed Central

    de la Garza, Rocio G.; Morales-Garza, Luis Alonso; Martin-Estal, Irene; Castilla-Cortazar, Inma

    2017-01-01

    Cirrhosis represents the final stage of chronic liver damage, which can be due to different factors such as alcohol, metabolic syndrome with liver steatosis, autoimmune diseases, drugs, toxins, and viral infection, among others. Nowadays, cirrhosis is an important health problem and it is an increasing cause of morbidity and mortality, being the 14th most common cause of death worldwide. The physiopathological pathways that lead to fibrosis and finally cirrhosis partly depend on the etiology. Nevertheless, some common features are shared in this complex mechanism. Recently, it has been demonstrated that cirrhosis is a dynamic process that can be altered in order to delay or revert fibrosis. In addition, when cirrhosis has been established, insulin-like growth factor-1 (IGF-1) deficiency or reduced availability is a common condition, independently of the etiology of chronic liver damage that leads to cirrhosis. IGF-1 deprivation seriously contributes to the progressive malnutrition of cirrhotic patient, increasing the vulnerability of the liver to establish an inflammatory and oxidative microenvironment with mitochondrial dysfunction. In this context, IGF-1 deficiency in cirrhotic patients can justify some of the common characteristics of these individuals. Several studies in animals and humans have been done in order to test the replacement of IGF-1 as a possible therapeutic option, with promising results. PMID:28270882

  11. Combination of three angiogenic growth factors has synergistic effects on sprouting of endothelial cell/mesenchymal stem cell-based spheroids in a 3D matrix.

    PubMed

    Kim, Sook Kyoung; Lee, Jaeyeon; Song, Myeongjin; Kim, Mirim; Hwang, Soon Jung; Jang, Hwanseok; Park, Yongdoo

    2016-11-01

    Combinations of angiogenic growth factors have been shown to have synergistic effects on angiogenesis and natural wound healing in various animal models. Each growth factor has unique roles during angiogenesis; vascular endothelial growth factor (VEGF) plays a key role during the initial step of angiogenesis, whereas PDGF functions in the maturation of blood vessels. We used a combination of three angiogenic growth factors to increase angiogenesis in vitro and in vivo. We chose VEGF as a basic factor and added platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) to induce angiogenesis in three in vitro and in vivo models: 3D angiogenesis assay, 3D co-culture, and matrigel plug implantation assay. Cell proliferation was significantly higher in co-cultured cells treated with PDGF + VEGF + FGF than in the control, single, or dual combination groups. mRNA expression of α-smooth muscle actin (α-SMA), von Willebrand factor (vWF), and CD105 was higher in the triple group (PDGF + VEGF + FGF) than in control, single, or dual combination groups. In the PDGF + VEGF + FGF group, the length and number of branches of spheroids was also significantly higher than in the control, single, or dual combination groups. Furthermore, in a nude mouse model, α-SMA expression was significantly higher in the PDGF + VEGF + FGF group than in other groups. In conclusion, the addition of PDGF and FGF to VEGF showed synergistic effects on angiogenesis in vitro and in vivo. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1535-1543, 2016. © 2015 Wiley Periodicals, Inc.

  12. Nerve Growth Factor Inhibits Sympathetic Neurons' Response to an Injury Cytokine

    NASA Astrophysics Data System (ADS)

    Shadiack, Annette M.; Vaccariello, Stacey A.; Sun, Yi; Zigmond, Richard E.

    1998-06-01

    Axonal damage to adult peripheral neurons causes changes in neuronal gene expression. For example, axotomized sympathetic, sensory, and motor neurons begin to express galanin mRNA and protein, and recent evidence suggests that galanin plays a role in peripheral nerve regeneration. Previous studies in sympathetic and sensory neurons have established that galanin expression is triggered by two consequences of nerve transection: the induction of leukemia inhibitory factor (LIF) and the reduction in the availability of the target-derived factor, nerve growth factor. It is shown in the present study that no stimulation of galanin expression occurs following direct application of LIF to intact neurons in the superior cervical sympathetic ganglion. Injection of animals with an antiserum to nerve growth factor concomitant with the application of LIF, on the other hand, does stimulate galanin expression. The data suggest that the response of neurons to an injury factor, LIF, is affected by whether the neurons still receive trophic signals from their targets.

  13. Growth differentiation factor-15 (GDF-15) suppresses in vitro angiogenesis through a novel interaction with connective tissue growth factor (CCN2).

    PubMed

    Whitson, Ramon J; Lucia, Marshall Scott; Lambert, James R

    2013-06-01

    Growth differentiation factor-15 (GDF-15) and the CCN family member, connective tissue growth factor (CCN2), are associated with cardiac disease, inflammation, and cancer. The precise role and signaling mechanism for these factors in normal and diseased tissues remains elusive. Here we demonstrate an interaction between GDF-15 and CCN2 using yeast two-hybrid assays and have mapped the domain of interaction to the von Willebrand factor type C domain of CCN2. Biochemical pull down assays using secreted GDF-15 and His-tagged CCN2 produced in PC-3 prostate cancer cells confirmed a direct interaction between these proteins. To investigate the functional consequences of this interaction, in vitro angiogenesis assays were performed. We demonstrate that GDF-15 blocks CCN2-mediated tube formation in human umbilical vein endothelial (HUVEC) cells. To examine the molecular mechanism whereby GDF-15 inhibits CCN2-mediated angiogenesis, activation of αV β3 integrins and focal adhesion kinase (FAK) was examined. CCN2-mediated FAK activation was inhibited by GDF-15 and was accompanied by a decrease in αV β3 integrin clustering in HUVEC cells. These results demonstrate, for the first time, a novel signaling pathway for GDF-15 through interaction with the matricellular signaling molecule CCN2. Furthermore, antagonism of CCN2 mediated angiogenesis by GDF-15 may provide insight into the functional role of GDF-15 in disease states. Copyright © 2012 Wiley Periodicals, Inc.

  14. Survival and growth of Cochlodinium polykrikoides red tide after addition of yellow loess.

    PubMed

    Lee, Young Sik; Kim, Jung Dong; Lim, Weol Ae; Lee, Sam Geun

    2009-11-01

    We examined the survival rate of Cochlodinium polykrikoides after yellow loess addition and conducted culture experiments to investigate the possibility that red tides maybe caused by C. polykrikoides individuals that are precipitated when loess is added. At least 15% of the C. polykrikoides cells that precipitated to the bottom layer either by the addition of loess or no addition survived for 1 week at all growth phases, rather than disappearing immediately after precipitating. However no live cells were observed after 20 days, regardless of phase or loess addition. In the exponential phase, the number of C. polykrikoides cells increased to >2886 cells ml(-1) after loess was added. However in the stationary phase, the number of cells did not increase until 18 days. In the exponential phase, those C. polykrikoides that survived precipitation caused by scattering loess on cultures did not appear to have the ability to cause red tides again because of the short red tide periods in the field, long lag time after loess addition, and low survival rate after loess addition.

  15. Carcass addition does not enhance juvenile salmonid biomass, growth, or retention in six Northwestern California streams.

    Treesearch

    Bret Harvey; Margaret A. Wilzbach

    2010-01-01

    Fisheries managers commonly consider the addition of salmon carcasses when seeking to enhance salmonid populations. However, the range of environmental conditions under which the technique is effective remains poorly defined. We addressed this issue by measuring the effects of wintertime addition of salmon carcasses on the biomass, growth, and retention of juvenile...

  16. Lactoferrin – A Novel Bone Growth Factor

    PubMed Central

    Naot, Dorit; Grey, Andrew; Reid, Ian R; Cornish, Jillian

    2005-01-01

    Lactoferrin is an iron-binding glycoprotein that belongs to the transferrin family. It is present in breast milk, in epithelial secretions, and in the secondary granules of neutrophils. In healthy subjects lactoferrin circulates at concentrations of 2–7 x 10−6 g/ml. Lactoferrin is a pleiotropic factor with potent antimicrobial and immunomodulatory activities. Recently, we have shown that lactoferrin can also promote bone growth. At physiological concentrations, lactoferrin potently stimulates the proliferation and differentiation of primary osteoblasts and also acts as a survival factor inhibiting apoptosis induced by serum withdrawal. Lactoferrin also affects osteoclast formation and, in murine bone marrow culture, lactoferrin potently inhibits osteoclastogenesis. In vivo, local injection of lactoferrin above the hemicalvaria of adult mice results in substantial increases in the dynamic histomorphometric indices of bone formation and bone area. The mitogenic effect of lactoferrin in osteoblast-like cells is mediated mainly through LRP1, a member of the family of low-density lipoprotein receptor-related proteins that are primarily known as endocytic receptors. Using confocal laser scanning microscopy, we demonstrated that fluorescently labeled lactoferrin is endocytosed and can be visualized in the cytoplasm of primary osteoblastic cells. Lactoferrin also induces activation of p42/44 MAPK signaling in primary osteoblasts, but the two pathways seem to operate independently as activation of MAPK signaling, but not endocytosis, is necessary for the mitogenic effect of lactoferrin. We conclude that lactoferrin may have a physiological role in bone growth and healing, and a potential therapeutic role as an anabolic factor in osteoporosis. PMID:16012127

  17. Comparison of human dermal fibroblasts (HDFs) growth rate in culture media supplemented with or without basic fibroblast growth factor (bFGF).

    PubMed

    Abdian, Narges; Ghasemi-Dehkordi, Payam; Hashemzadeh-Chaleshtori, Morteza; Ganji-Arjenaki, Mahbobe; Doosti, Abbas; Amiri, Beheshteh

    2015-12-01

    Basic fibroblast growth factor (bFGF or FGF-2) is a member of the FGF family secreted by different kinds of cells like HDFs and it is an important nutritional factor for cell growth and differentiation. The HDFs release bFGF in culture media at very low. The present study aims to investigate the HDFs growth rate in culture media supplemented either with or without bFGF. In brief, HDFs were isolated from human foreskin sample and were cultured in vitro in media containing bFGF and lack of this factor. The cells growth rate was calculated by trypan blue. The karyotyping was performed using G-banding to investigate the chromosomal abnormality of HDFs in both groups. Total RNA of each groups were extracted and cDNA samples were synthesized then, real-time Q-PCR was used to measure the expression level of p27kip1 and cyclin D1 genes normalized to internal control gene (GAPDH). The karyotype analysis showed that HDFs cultured in media or without bFGF had normal karyotype (46 chromosomes, XY) and chromosomal abnormalities were not observed. The cell growth rates in both groups were normal with proliferated exponentially but the slope of growth curve in HDFs cultured in media containing bFGF was increased. Karyotyp test showed that bFGF does not affect on cytogenetic stability of cells. The survey of p27kip1 and cyclin D1 genes by real-time Q-PCR showed that the expression level of these genes were up-regulated when adding bFGF in culture media (p < 0.05). The findings of the present study demonstrate that appropriate supplementation of culture media with growth factor like bFGF could enhance the proliferation and differentiation capacity of cells and improve cells growth rate. Similarly, fibroblast growth factors did not induce any chromosomal abnormality in cells. Furthermore, in HDFs cultured in bFGF supplemented media, the p27kip1 and cyclin D1 genes were up-regulated and suggesting an important role for bFGF in cell-cycle regulation and progression and fibroblast

  18. Alginate Sulfates Mitigate Binding Kinetics of Proangiogenic Growth Factors with Receptors toward Revascularization.

    PubMed

    Schmidt, John; Lee, Min Kyung; Ko, Eunkyung; Jeong, Jae Hyun; DiPietro, Luisa A; Kong, Hyunjoon

    2016-07-05

    Ever since proangiogenic growth factors have been used as a vascular medicine to treat tissue ischemia, efforts have been increasingly made to develop a method to enhance efficacy of growth factors in recreating microvascular networks, especially at low dose. To this end, we hypothesized that polysaccharides substituted with sulfate groups would amplify growth factor receptor activation and stimulate phenotypic activities of endothelial cells involved in neovascularization. We examined this hypothesis by modifying alginate with a controlled number of sulfates and using it to derive a complex with vascular endothelial growth factor (VEGF), as confirmed with fluorescence resonance energy transfer (FRET) assay. Compared with the bare VEGF and with a mixture of VEGF and unmodified alginates, the VEGF complexed with alginate sulfates significantly reduced the dissociation rate with the VEGFR-2, elevated VEGFR-2 phosphorylation level, and increased the number of endothelial sprouts in vitro. Furthermore, the VEGF-alginate sulfate complex improved recovery of perfusion in an ischemic hindlimb of a mouse due to the increase of the capillary density. Overall, this study not only demonstrates an important cofactor of VEGF but also uncovers an underlying mechanism by which the cofactor mitigates the VEGF-induced signaling involved in the binding kinetics and activation of VEGFR. We therefore believe that the results of this study will be highly useful in improving the therapeutic efficacy of various growth factors and expediting their uses in clinical treatments of wounds and tissue defects.

  19. Involvement of Vascular Endothelial Growth Factor in Kaposi's Sarcoma Associated with Acquired Immunodeficiency Syndrome

    PubMed Central

    Sakurada, Shinsaku; Kato, Tetsuji; Mashiba, Kohichi; Mori, Shigeo

    1996-01-01

    To examine the role of vascular endothelial growth factor (VEGF) in the development of edema associated with Kaposi's sarcoma (KS) in acquired immunodeficiency syndrome (AIDS), we exploited animal model systems to detect the activity that induces vascular hyper‐permeability (VHP) using cultured AIDS‐KS spindle cells. Cultured AIDS‐KS spindle cells and conditioned medium (AIDS‐KS‐CM) that had been semi‐purified through a heparin affinity column were tested for the ability to induce VHP in animals. The AIDS‐KS spindle cells and AIDS‐KS‐CM induced VHP that was histamine‐independent. The VHP‐inducing activity was detected in the 0.5 M NaCl fraction from the heparin affinity column and was blocked by anti‐VEGF neutralizing antibody. In addition, the production of VEGF was demonstrated in fresh AIDS‐KS tissue as well as in cultured AIDS‐KS cells, while control cells were negative for VEGF production. From these observations, we concluded that AIDS‐KS cells produce a factor(s) that promotes VHP, and this factor could be VEGF. PMID:9045943

  20. Increased and correlated expression of connective tissue growth factor and transforming growth factor beta 1 in surgically removed periodontal tissues with chronic periodontitis.

    PubMed

    Mize, T W; Sundararaj, K P; Leite, R S; Huang, Y

    2015-06-01

    Both gingival tissue destruction and regeneration are associated with chronic periodontitis, although the former overwhelms the latter. Studies have shown that transforming growth factor beta 1 (TGF-β1), a growth factor largely involved in tissue regeneration and remodeling, is upregulated in chronic periodontitis. However, the gingival expression of connective tissue growth factor (CTGF or CCN2), a TGF-β1-upregulated gene, in patients with periodontitis remains undetermined. Although both CTGF/CCN2 and TGF-b1 increase the production of extracellular matrix, they have many different biological functions. Therefore, it is important to delineate the impact of periodontitis on gingival CTGF/CCN2 expression. Periodontal tissue specimens were collected from seven individuals without periodontitis (group 1) and from 14 with periodontitis (group 2). The expression of CTGF and TGFβ1 mRNAs were quantified using real-time PCR. Analysis using the nonparametric Mann-Whitney U-test showed that the levels of expression of both CTGF/CCN2 and TGFβ1 mRNAs were significantly increased in individuals with periodontitis compared with individuals without periodontitis. Furthermore, analysis using a nonparametric correlation (Spearman r) test showed a positive correlation between TGFβ1 and CTGF/CCN2 mRNAs. The gingival expression levels of CTGF/CCN2 and TGFβ1 mRNAs in individuals with periodontitis are upregulated and correlated. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Phenotypic differences between oral and skin fibroblasts in wound contraction and growth factor expression.

    PubMed

    Shannon, Diane B; McKeown, Scott T W; Lundy, Fionnuala T; Irwin, Chris R

    2006-01-01

    Wounds of the oral mucosa heal in an accelerated fashion with reduced scarring compared with cutaneous wounds. The differences in healing outcome between oral mucosa and skin could be because of phenotypic differences between the respective fibroblast populations. This study compared paired mucosal and dermal fibroblasts in terms of collagen gel contraction, alpha-smooth muscle actin expression (alpha-SMA), and production of the epithelial growth factors: keratinocyte growth factor (KGF) and hepatocyte growth factor/scatter factor (HGF). The effects of transforming growth factor -beta1 and -beta3 on each parameter were also determined. Gel contraction in floating collagen lattices was determined over a 7-day period. alpha-SMA expression by fibroblasts was determined by Western blotting. KGF and HGF expression were determined by an enzyme-linked immunosorbent assay. Oral fibroblasts induced accelerated collagen gel contraction, yet surprisingly expressed lower levels of alpha-SMA. Oral cells also produced significantly greater levels of both KGF and HGF than their dermal counterparts. Transforming growth factor-beta1 and -beta3, over the concentration range of 0.1-10 ng/mL, had similar effects on cell function, stimulating both gel contraction and alpha-SMA production, but inhibiting KGF and HGF production by both cell types. These data indicate phenotypic differences between oral and dermal fibroblasts that may well contribute to the differences in healing outcome between these two tissues.

  2. Expression of insulin-like growth factor-2 receptors on EL4 lymphoma cells overexpressing growth hormone.

    PubMed

    Farmer, John T; Weigent, Douglas A

    2007-01-01

    In the present study, we report the upregulation of functional IGF-2Rs in cells overexpressing growth hormone (GH). EL4 lymphoma cells stably transfected with an rGH cDNA overexpression vector (GHo) exhibited an increase in the binding of (125)I-IGF-2 with no change in the binding affinity compared to vector alone controls. An increase in the expression of the insulin-like growth factor-2 receptor (IGF-2R) in cells overexpressing GH was confirmed by Western blot analysis and IGF-2R promoter luciferase assays. EL4 cells produce insulin-like growth factor-2 (IGF-2) as detected by the reverse transcription-polymerase chain reaction (RT-PCR); however, no IGF-2 protein was detected by Western analysis. The increase in the expression of the IGF-2R resulted in greater levels of IGF-2 uptake in GHo cells compared to vector alone controls. The data suggest that one of the consequences of the overexpression of GH is an increase in the expression of the IGF-2R.

  3. Structure of a highly stable mutant of human fibroblast growth factor 1.

    PubMed

    Szlachcic, Anna; Zakrzewska, Małgorzata; Krowarsch, Daniel; Os, Vibeke; Helland, Ronny; Smalås, Arne O; Otlewski, Jacek

    2009-01-01

    Fibroblast growth factors (FGFs) are involved in diverse cellular processes such as cell migration, angiogenesis, osteogenesis, wound healing and embryonic and foetal development. Human acidic fibroblast growth factor (FGF-1) is the only member of the FGF family that binds with high affinity to all four FGF receptors and thus is considered to be the human mitogen with the broadest specificity. However, pharmacological applications of FGF-1 are limited owing to its low stability. It has previously been reported that the introduction of single mutations can significantly improve the stability of FGF-1 and its resistance to proteolytic degradation. Here, the structure of the Q40P/S47I/H93G triple mutant of FGF-1, which exhibits much higher stability, a prolonged half-life and enhanced mitogenic activity, is presented. Compared with the wild-type structure, three localized conformational changes in the stable triple mutant were observed, which is in agreement with the perfect energetic additivity of the single mutations described in a previous study. The huge change in FGF-1 stability (the denaturation temperature increased by 21.5 K, equivalent to DeltaDeltaG(den) = 24.3 kJ mol(-1)) seems to result from the formation of a short 3(10)-helix (position 40), an improvement in the propensity of amino acids to form beta-sheets (position 47) and the rearrangement of a local hydrogen-bond network (positions 47 and 93).

  4. Connective tissue growth factor is expressed in bone marrow stromal cells and promotes interleukin-7-dependent B lymphopoiesis.

    PubMed

    Cheung, Laurence C; Strickland, Deborah H; Howlett, Meegan; Ford, Jette; Charles, Adrian K; Lyons, Karen M; Brigstock, David R; Goldschmeding, Roel; Cole, Catherine H; Alexander, Warren S; Kees, Ursula R

    2014-07-01

    Hematopoiesis occurs in a complex bone marrow microenvironment in which bone marrow stromal cells provide critical support to the process through direct cell contact and indirectly through the secretion of cytokines and growth factors. We report that connective tissue growth factor (Ctgf, also known as Ccn2) is highly expressed in murine bone marrow stromal cells. In contrast, connective tissue growth factor is barely detectable in unfractionated adult bone marrow cells. While connective tissue growth factor has been implicated in hematopoietic malignancies, and is known to play critical roles in skeletogenesis and regulation of bone marrow stromal cells, its role in hematopoiesis has not been described. Here we demonstrate that the absence of connective tissue growth factor in mice results in impaired hematopoiesis. Using a chimeric fetal liver transplantation model, we show that absence of connective tissue growth factor has an impact on B-cell development, in particular from pro-B to more mature stages, which is linked to a requirement for connective tissue growth factor in bone marrow stromal cells. Using in vitro culture systems, we demonstrate that connective tissue growth factor potentiates B-cell proliferation and promotes pro-B to pre-B differentiation in the presence of interleukin-7. This study provides a better understanding of the functions of connective tissue growth factor within the bone marrow, showing the dual regulatory role of the growth factor in skeletogenesis and in stage-specific B lymphopoiesis. Copyright© Ferrata Storti Foundation.

  5. Connective tissue growth factor is expressed in bone marrow stromal cells and promotes interleukin-7-dependent B lymphopoiesis

    PubMed Central

    Cheung, Laurence C.; Strickland, Deborah H.; Howlett, Meegan; Ford, Jette; Charles, Adrian K.; Lyons, Karen M.; Brigstock, David R.; Goldschmeding, Roel; Cole, Catherine H.; Alexander, Warren S.; Kees, Ursula R.

    2014-01-01

    Hematopoiesis occurs in a complex bone marrow microenvironment in which bone marrow stromal cells provide critical support to the process through direct cell contact and indirectly through the secretion of cytokines and growth factors. We report that connective tissue growth factor (Ctgf, also known as Ccn2) is highly expressed in murine bone marrow stromal cells. In contrast, connective tissue growth factor is barely detectable in unfractionated adult bone marrow cells. While connective tissue growth factor has been implicated in hematopoietic malignancies, and is known to play critical roles in skeletogenesis and regulation of bone marrow stromal cells, its role in hematopoiesis has not been described. Here we demonstrate that the absence of connective tissue growth factor in mice results in impaired hematopoiesis. Using a chimeric fetal liver transplantation model, we show that absence of connective tissue growth factor has an impact on B-cell development, in particular from pro-B to more mature stages, which is linked to a requirement for connective tissue growth factor in bone marrow stromal cells. Using in vitro culture systems, we demonstrate that connective tissue growth factor potentiates B-cell proliferation and promotes pro-B to pre-B differentiation in the presence of interleukin-7. This study provides a better understanding of the functions of connective tissue growth factor within the bone marrow, showing the dual regulatory role of the growth factor in skeletogenesis and in stage-specific B lymphopoiesis. PMID:24727816

  6. Novel vascular endothelial growth factor blocker improves cellular viability and reduces hypobaric hypoxia-induced vascular leakage and oedema in rat brain.

    PubMed

    Saraswat, Deepika; Nehra, Sarita; Chaudhary, Kamal; CVS, Siva Prasad

    2015-05-01

    Vascular endothelial growth factor (VEGF) is an important cerebral angiogenic and permeability factor under hypoxia. There is a need to find effective molecules that may ameliorate hypoxia-induced cerebral oedema. In silico identification of novel candidate molecules that block VEGF-A site were identified and validated with a Ramachandran plot. The active site residues of VEGF-A were detected by Pocketfinder, CASTp, and DogSiteScorer. Based on in silico data, three VEGF-A blocker (VAB) candidate molecules (VAB1, VAB2, and VAB3) were checked for improvement in cellular viability and regulation of VEGF levels in N2a cells under hypoxia (0.5% O2 ). Additionally, the best candidate molecule's efficacy was assessed in male Sprague-Dawley rats for its ameliorative effect on cerebral oedema and vascular leakage under hypobaric hypoxia 7260 m. All experimental results were compared with the commercially available VEGF blocker sunitinib. Vascular endothelial growth factor-A blocker 1 was found most effective in increasing cellular viability and maintaining normal VEGF levels under hypoxia (0.5% oxygen) in N2a cells. Vascular endothelial growth factor-A blocker 1 effectively restored VEGF levels, decreased cerebral oedema, and reduced vascular leakage under hypobaric hypoxia when compared to sunitinib-treated rats. Vascular endothelial growth factor-A blocker 1 may be a promising candidate molecule for ameliorating hypobaric hypoxia-induced vasogenic oedema by regulating VEGF levels. © 2015 Wiley Publishing Asia Pty Ltd.

  7. Promotion of human early embryonic development and blastocyst outgrowth in vitro using autocrine/paracrine growth factors.

    PubMed

    Kawamura, Kazuhiro; Chen, Yuan; Shu, Yimin; Cheng, Yuan; Qiao, Jie; Behr, Barry; Pera, Renee A Reijo; Hsueh, Aaron J W

    2012-01-01

    Studies using animal models demonstrated the importance of autocrine/paracrine factors secreted by preimplantation embryos and reproductive tracts for embryonic development and implantation. Although in vitro fertilization-embryo transfer (IVF-ET) is an established procedure, there is no evidence that present culture conditions are optimal for human early embryonic development. In this study, key polypeptide ligands known to be important for early embryonic development in animal models were tested for their ability to improve human early embryo development and blastocyst outgrowth in vitro. We confirmed the expression of key ligand/receptor pairs in cleavage embryos derived from discarded human tri-pronuclear zygotes and in human endometrium. Combined treatment with key embryonic growth factors (brain-derived neurotrophic factor, colony-stimulating factor, epidermal growth factor, granulocyte macrophage colony-stimulating factor, insulin-like growth factor-1, glial cell-line derived neurotrophic factor, and artemin) in serum-free media promoted >2.5-fold the development of tri-pronuclear zygotes to blastocysts. For normally fertilized embryos, day 3 surplus embryos cultured individually with the key growth factors showed >3-fold increases in the development of 6-8 cell stage embryos to blastocysts and >7-fold increase in the proportion of high quality blastocysts based on Gardner's criteria. Growth factor treatment also led to a 2-fold promotion of blastocyst outgrowth in vitro when day 7 surplus hatching blastocysts were used. When failed-to-be-fertilized oocytes were used to perform somatic cell nuclear transfer (SCNT) using fibroblasts as donor karyoplasts, inclusion of growth factors increased the progression of reconstructed SCNT embryos to >4-cell stage embryos. Growth factor supplementation of serum-free cultures could promote optimal early embryonic development and implantation in IVF-ET and SCNT procedures. This approach is valuable for infertility

  8. Diminished survival of human cytotrophoblast cells exposed to hypoxia/reoxygenation injury and associated reduction of heparin-binding epidermal growth factor-like growth factor.

    PubMed

    Leach, Richard E; Kilburn, Brian A; Petkova, Anelia; Romero, Roberto; Armant, D Randall

    2008-04-01

    The antiapoptotic action of heparin-binding epidermal growth factor (HBEGF)-like growth factor and its regulation by O(2) constitutes a key factor for trophoblast survival. The hypothesis that cytotrophoblast survival is compromised by exposure to hypoxia-reoxygenation (H/R) injury, which may contribute to preeclampsia and some missed abortions, prompted us to investigate HBEGF regulation and its role as a survival factor during H/R in cytotrophoblast cells. A transformed human first-trimester cytotrophoblast cell line HTR-8/SVneo was exposed to H/R (2% O(2) followed by 20% O(2)) and assessed for HBEGF expression and cell death. Cellular HBEGF declined significantly within 30 minutes of reoxygenation after culture at 2% O(2). H/R significantly reduced proliferation and increased cell death when compared with trophoblast cells cultured continuously at 2% or 20% O(2). Restoration of cell survival also was achieved by adding recombinant HBEGF during reoxygenation. HBEGF inhibited apoptosis through its binding to either human epidermal receptor (HER)-1 or HER4, its cognate receptors. These results provide evidence that cytotrophoblast exposure to H/R induces apoptosis and decreased cell proliferation. HBEGF accumulation is diminished under these conditions, whereas restoration of HBEGF signaling improves trophoblast survival.

  9. Inhibitory effects of hepatocyte growth factor and interleukin-6 on transforming growth factor-beta1 mediated vocal fold fibroblast-myofibroblast differentiation.

    PubMed

    Vyas, Bimal; Ishikawa, Keiko; Duflo, Suzy; Chen, Xia; Thibeault, Susan L

    2010-05-01

    The role of myofibroblasts in vocal fold scarring has not been extensively studied, partly because of the lack of a robust in vitro model. The objective of this investigation was to develop and characterize a myofibroblast in vitro model that could be utilized to investigate the molecular mechanism of myofibroblast differentiation and function in injured vocal fold tissue. Differentiation of human primary vocal fold fibroblasts (hVFFs) to myofibroblasts was stimulated with 5, 10, or 20 ng/mL of recombinant transforming growth factor-beta1 (TGF-beta1). Cultures were analyzed by immunofluorescence and Western blotting, with an alpha-smooth muscle actin (alpha-SMA) antibody used as a myofibroblast marker. Normal rabbit vocal folds were treated with 10 ng/mL of TGF-beta1 for 7 days for in vivo corroboration. The effects of interleukin-6 (IL-6) and hepatocyte growth factor (HGF) on myofibroblast differentiation were studied with Western blots. The hVFFs demonstrated positive alpha-SMA labeling in cells stimulated by 10 and 20 ng/mL TGF-beta1, indicating that hVFFs were capable of differentiation to myofibroblasts. Transforming growth factor-beta1 induced the largest increase in alpha-SMA at 10 ng/mL on day 5 of treatment. Both HGF and IL-6 suppressed the expression of TGF-beta1-induced alpha-SMA. Our work characterizes a useful in vitro model of TGF-beta1-mediated vocal fold fibroblast-myofibroblast differentiation. The extent of differentiation appears to be attenuated by HGF, suggesting a potential mechanism to support prior work indicating that HGF plays a protective role in reducing scar formation in vocal fold injuries. Paradoxically, IL-6, which has been shown to play a profibrotic role in dermal studies, also attenuated the TGF-beta1 response.

  10. Diversification of the insulin-like growth factor 1 gene in mammals.

    PubMed

    Rotwein, Peter

    2017-01-01

    Insulin-like growth factor 1 (IGF1), a small, secreted peptide growth factor, is involved in a variety of physiological and patho-physiological processes, including somatic growth, tissue repair, and metabolism of carbohydrates, proteins, and lipids. IGF1 gene expression appears to be controlled by several different signaling cascades in the few species in which it has been evaluated, with growth hormone playing a major role by activating a pathway involving the Stat5b transcription factor. Here, genes encoding IGF1 have been evaluated in 25 different mammalian species representing 15 different orders and ranging over ~180 million years of evolutionary diversification. Parts of the IGF1 gene have been fairly well conserved. Like rat Igf1 and human IGF1, 21 of 23 other genes are composed of 6 exons and 5 introns, and all 23 also contain recognizable tandem promoters, each with a unique leader exon. Exon and intron lengths are similar in most species, and DNA sequence conservation is moderately high in orthologous exons and proximal promoter regions. In contrast, putative growth hormone-activated Stat5b-binding enhancers found in analogous locations in rodent Igf1 and in human IGF1 loci, have undergone substantial variation in other mammals, and a processed retro-transposed IGF1 pseudogene is found in the sloth locus, but not in other mammalian genomes. Taken together, the fairly high level of organizational and nucleotide sequence similarity in the IGF1 gene among these 25 species supports the contention that some common regulatory pathways had existed prior to the beginning of mammalian speciation.

  11. ACTINOMYCES NEUII ENDOPHTHALMITIS AFTER INTRAVITREAL ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR INJECTION.

    PubMed

    Sahni, Sakshi; Watson, Randee Miller; Sheth, Veeral S

    2017-01-01

    To describe a case of acute endophthalmitis caused by Actinomyces neuii after intravitreal anti-vascular endothelial growth factor injection. Observational case report, review of published literature. A 67-year-old white man with wet age-related macular degeneration developed endophthalmitis secondary to A. neuii on the 10th day after intravitreal anti-vascular endothelial growth factor injection. Both anterior chamber and vitreous cultures were positive for A. neuii. He was treated successfully with intravitreal injection of vancomycin and ceftazidime. This is the first published report of culture-positive endophthalmitis caused by A. neuii after intravitreal injection.

  12. Role of fibroblast growth factor receptor signaling in kidney development.

    PubMed

    Bates, Carlton M

    2007-03-01

    Fibroblast growth factor receptors (Fgfrs) are expressed in the ureteric bud and metanephric mesenchyme of the developing kidney. Furthermore, in vitro and in vivo studies have shown that exogenous fibroblast growth factors (Fgfs) increase growth and maturation of the metanephric mesenchyme and ureteric bud. Deletion of fgf7, fgf10, and fgfr2IIIb (the receptor isoform that binds Fgf7 and Fgf10) in mice lead to smaller kidneys with fewer collecting ducts and nephrons. Overexpression of a dominant negative receptor isoform in transgenic mice has revealed more striking defects including renal aplasia or severe dysplasia. Moreover, deletion of many fgf ligands and receptors in mice results in early embryonic lethality, making it difficult to determine their roles in kidney development. Recently, conditional targeting approaches revealed that deletion of fgf8 from the metanephric mesenchyme interrupts nephron formation. Furthermore, deletion of fgfr2 from the ureteric bud resulted in both ureteric bud branching and stromal mesenchymal patterning defects. Deletion of both fgfr1 and fgfr2 in the metanephric mesenchyme resulted in renal aplasia, characterized by defects in metanephric mesenchyme formation and initial ureteric bud elongation and branching. Thus, Fgfr signaling is critical for growth and patterning of all renal lineages at early and later stages of kidney development.

  13. Assessment of insulin-like growth factor-1 (IGF-I) level in patients with rheumatic mitral stenosis.

    PubMed

    Deveci, Onur S; Yavuz, Bunyamin; Sen, Omer; Deniz, Ali; Ozkan, Selcuk; Dal, Kursat; Ata, Naim; Baser, Salih; Akin, Kadir O; Kucukazman, Metin; Beyan, Esin; Ertugrul, Derun T

    2015-03-01

    Insulin-like growth factor-1 may serve some regulatory function in the immune system. Rheumatic mitral stenosis is related to autoimmune heart valve damage after streptococcal infection. The aim of this study was to assess the level of insulin-like growth factor-1 and its correlation with the Wilkins score in patients with rheumatic mitral stenosis. A total of 65 patients with rheumatic mitral stenosis and 62 age- and sex-matched control subjects were enrolled in this study. All subjects underwent transthoracic echocardiography. The mitral valve area and Wilkins score were evaluated for all patients. Biochemical parameters and serum insulin-like growth factor-1 levels were measured. Demographic data were similar in the rheumatic mitral stenosis and control groups. The mean mitral valve area was 1.6±0.4 cm2 in the rheumatic mitral stenosis group. The level of insulin-like growth factor-1 was significantly higher in the rheumatic mitral stenosis group than in the control group (104 (55.6-267) versus 79.1 (23.0-244.0) ng/ml; p=0.039). There was a significant moderate positive correlation between insulin-like growth factor-1 and thickening of leaflets score of Wilkins (r=0.541, p<0.001). The present study demonstrated that serum insulin-like growth factor-1 levels were significantly higher in the rheumatic mitral stenosis group compared with control subjects and that insulin-like growth factor-1 level was also correlated with the Wilkins score. It can be suggested that there may be a link between insulin-like growth factor-1 level and immune pathogenesis of rheumatic mitral stenosis.

  14. Sustained Partial Sleep Deprivation: Effects on Immune Modulation and Growth Factors

    NASA Technical Reports Server (NTRS)

    Mullington, Janet M.

    1999-01-01

    from this larger study: a 4.2 hour per night condition, and a 8.2 hour per night condition. During space flight, muscle mass and bone density are reduced, apparently due to loss of GH and IGF-I, associated with microgravity. Since >70% of growth hormone (GH) is secreted at night in normal adults, we hypothesized that the chronic sleep restriction to 4 hours per night would reduce GH levels as measured in the periphery. In this synergy project, in collaboration with the "Muscle Alterations and Atrophy Team ", we are measuring insulin-like growth factor-I (IGF-I) in peripheral circulation to test the prediction that it will be reduced by chronic sleep restriction. In addition to stress modulation of immune function, recent research suggests that sleep is also involved. While we all have the common experience of being sleepy when suffering from infection, and being susceptible to infection when not getting enough sleep, the mechanisms involved in this process are not understood and until recently have gone largely overlooked. We believe that the immune function changes seen in spaceflight may also be related to the cumulative effects of sleep loss. Moreover, in space flight, the possibility of compromised immune function or of the reactivation of latent viruses are serious potential hazards for the success of long term missions. Confined living conditions, reduced sleep, altered diet and stress are all factors that may compromise immune function, thereby increasing the risks of developing and transmitting disease. Medical complications, which would not pose serious problems on earth, may be disastrous if they emerged in space.

  15. The diagnostic value of plasma N-terminal connective tissue growth factor levels in children with heart failure.

    PubMed

    Li, Gang; Song, Xueqing; Xia, Jiyi; Li, Jing; Jia, Peng; Chen, Pengyuan; Zhao, Jian; Liu, Bin

    2017-01-01

    The aim of this study was to assess the diagnostic value of plasma N-terminal connective tissue growth factor in children with heart failure. Methods and results Plasma N-terminal connective tissue growth factor was determined in 61 children, including 41 children with heart failure, 20 children without heart failure, and 30 healthy volunteers. The correlations between plasma N-terminal connective tissue growth factor levels and clinical parameters were investigated. Moreover, the diagnostic value of N-terminal connective tissue growth factor levels was evaluated. Compared with healthy volunteers and children without heart failure, plasma N-terminal connective tissue growth factor levels were significantly elevated in those with heart failure (p0.05), but it obviously improved the ability of diagnosing heart failure in children, as demonstrated by the integrated discrimination improvement (6.2%, p=0.013) and net re-classification improvement (13.2%, p=0.017) indices. Plasma N-terminal connective tissue growth factor is a promising diagnostic biomarker for heart failure in children.

  16. Gab1 Mediates Hepatocyte Growth Factor-Stimulated Mitogenicity and Morphogenesis in Multipotent Myeloid Cells

    PubMed Central

    Felici, Angelina; Giubellino, Alessio; Bottaro, Donald P.

    2012-01-01

    Hepatocyte growth factor (HGF)-stimulated mitogenesis, motogenesis and morphogenesis in various cell types begins with activation of the Met receptor tyrosine kinase and the recruitment of intracellular adaptors and kinase substrates. The adapter protein Gab1 is a critical effector and substrate of activated Met, mediating morphogenesis, among other activities, in epithelial cells. To define its role downstream of Met in hematopoietic cells, Gab1 was expressed in the HGF-responsive, Gab1-negative murine myeloid cell line 32D. Interestingly, the adhesion and motility of Gab1-expressing cells were significantly greater than parental cells, independent of growth factor treatment. Downstream of activated Met, Gab1 expression was specifically associated with rapid Shp-2 recruitment and activation, increased mitogenic potency, suppression of GATA-1 expression and concomitant upregulation of GATA-2 transcription. In addition to enhanced proliferation, continuous culture of Gab1-expressing 32D cells in HGF resulted in cell attachment, filopodia extension and phenotypic changes suggestive of monocytic differentiation. Our results suggest that in myeloid cells, Gab1 is likely to enhance HGF mitogenicity by coupling Met to Shp-2 and GATA-2 expression, thereby potentially contributing to normal myeloid differentiation as well as oncogenic transformation. PMID:20506405

  17. New insights into the molecular interaction of the C-terminal sequence of CXCL4 with fibroblast growth factor-2.

    PubMed

    Ragona, Laura; Tomaselli, Simona; Quemener, Cathy; Zetta, Lucia; Bikfalvi, Andreas

    2009-04-24

    Full-length CXCL4 chemokine and a peptide derived from its carboxyl-terminal domain exhibits significant antiangiogenic and anti-tumor activity in vivo and in vitro by interacting with fibroblast growth factor (FGF). In this study we used NMR spectroscopy to characterize at a molecular level the interactions between CXCL4 (47-70) and FGF-2 identifying the peptide residues mainly involved in the contact area with the growth factor. Altogether NMR data point to a major role of the hydrophobic contributions of the C-terminal region of CXCL4 (47-70) peptide in addition to specific contacts established by the N-terminal region through cysteine side chain. The proposed recognition mode constitutes a rationale for the observed effects of CXCL4 (47-70) on FGF-2 biological activity and lays the basis for developing novel inhibitors of angiogenesis.

  18. Hepatocyte growth factor/scatter factor enhances the invasion of mesothelioma cell lines and the expression of matrix metalloproteinases

    PubMed Central

    Harvey, P; Clark, I M; Jaurand, M-C; Warn, R M; Edwards, D R

    2000-01-01

    Hepatocyte growth factor/scatter factor (HGF/SF) is a multifunctional factor involved both in development and tissue repair, as well as pathological processes such as cancer and metastasis. It has been identified in vivo in many types of tumours together with its tyrosine kinase receptor, Met. We show here that exogenous HGF/SF acts as a strong chemoattractant for human mesothelioma cell lines. The factor also enhanced cell adhesion to and invasion into Matrigel. The mesothelioma cell lines synthesized a panel of matrix metalloproteinases critical for tumour progression such as MMP-1, 2, 3, 9 and membrane-bound MT1-MMP. HGF/SF stimulated the expression of MMP-1, 9 and MT1-MMP and had a slight effect on expression of the MMP inhibitor TIMP-1 but not TIMP-2. However, there was no simple correlation between the levels of MMPs and TIMPs of the cell lines and their different invasion properties or between HGF/SF stimulatory effects on MMP expression and invasion. In addition, effects of protease inhibitors on invasion suggested that serine proteases were also expressed in human mesothelioma cell lines and were involved in HGF/SF-induced invasion. The results show a predominant role for HGF/SF in mesothelioma cell invasion, stimulating simultaneously adhesion, motility, invasion and regulation of MMP and TIMP levels. © 2000 Cancer Research Campaign PMID:11027427

  19. Low-level laser therapy promotes dendrite growth via upregulating brain-derived neurotrophic factor expression

    NASA Astrophysics Data System (ADS)

    Meng, Chengbo; He, Zhiyong; Xing, Da

    2014-09-01

    Downregulation of brain-derived neurotrophic factor (BDNF) in the hippocampus occurs early in the progression of Alzheimer's disease (AD). Since BDNF plays a critical role in neuronal survival and dendrite growth, BDNF upregulation may contribute to rescue dendrite atrophy and cell loss in AD. Low-level laser therapy (LLLT) has been demonstrated to regulate neuronal function both in vitro and in vivo. In the present study, we found that LLLT rescued neurons loss and dendritic atrophy via the increase of both BDNF mRNA and protein expression. In addition, dendrite growth was improved after LLLT, characterized by upregulation of PSD95 expression, and the increase in length, branching, and spine density of dendrites in hippocampal neurons. Together, these studies suggest that upregulation of BDNF with LLLT can ameliorate Aβ-induced neurons loss and dendritic atrophy, thus identifying a novel pathway by which LLLT protects against Aβ-induced neurotoxicity. Our research may provide a feasible therapeutic approach to control the progression of Alzheimer's disease.

  20. 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.