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Sample records for hepatoma-derived growth factor

  1. Hepatoma-Derived Growth Factor: Its Possible Involvement in the Progression of Hepatocellular Carcinoma.

    PubMed

    Enomoto, Hirayuki; Nakamura, Hideji; Liu, Weidong; Nishiguchi, Shuhei

    2015-06-19

    The development of hepatocellular carcinoma (HCC) is an important complication of viral infection induced by hepatitis virus C, and our major research theme is to identify a new growth factor related to the progression of HCC. HDGF (hepatoma-derived growth factor) is a novel growth factor that belongs to a new gene family. HDGF was initially purified from the conditioned medium of a hepatoma cell line. HDGF promotes cellular proliferation as a DNA binding nuclear factor and a secreted protein acting via a receptor-mediated pathway. HDGF is a unique multi-functional protein that can function as a growth factor, angiogenic factor and anti-apoptotic factor and it participates in the development and progression of various malignant diseases. The expression level of HDGF may be an independent prognostic factor for predicting the disease-free and overall survival in patients with various malignancies, including HCC. Furthermore, the overexpression of HDGF promotes the proliferation of HCC cells, while a reduction in the HDGF expression inhibits the proliferation of HCC cells. This article provides an overview of the characteristics of HDGF and describes the potential role of HDGF as a growth-promoting factor for HCC.

  2. The regulatory role of hepatoma-derived growth factor as an angiogenic factor in the eye.

    PubMed

    LeBlanc, Michelle E; Wang, Weiwen; Chen, Xiuping; Ji, Yanli; Shakya, Akhalesh; Shen, Chen; Zhang, Chenming; Gonzalez, Vivianne; Brewer, Megan; Ma, Jian-Xing; Wen, Rong; Zhang, Fangliang; Li, Wei

    2016-01-01

    Hepatoma-derived growth factor (HDGF) is a mitogen that promotes endothelial proliferation and neuronal survival. Using a unique technology of ligandomics, we recently identified HDGF as a retinal endothelial binding protein. The purpose of this study is to examine the role of HDGF in regulating ocular vasculature and the expression of HDGF in the retina. HDGF expression in the retinal was analyzed with western blot and immunohistochemistry. Angiogenic activity was investigated in human retinal microvascular endothelial cells (HRMVECs) with in vitro endothelial proliferation, migration, and permeability assays. In vivo angiogenic activity was quantified with a corneal pocket assay. The Evans blue assay and western blot using anti-mouse albumin were performed to detect the capacity of HDGF to induce retinal vascular leakage. Immunohistochemistry revealed that HDGF is expressed in the retina with a distinct pattern. HDGF was detected in retinal ganglion cells and the inner nuclear layer but not in the inner plexiform layer, suggesting that HDGF is expressed in the nucleus, but not in the cytoplasm, of retinal neurons. In contrast to family member HDGF-related protein 3 (HRP-3) that has no expression in photoreceptors, HDGF is also present in the outer nuclear layer and the inner and outer segments of photoreceptors. This suggests that HDGF is expressed in the nucleus as well as the cytoplasm of photoreceptors. In vitro functional assays showed that HDGF induced the proliferation, migration, and permeability of HRMVECs. Corneal pocket assay indicated that HDGF directly stimulated angiogenesis in vivo. Intravitreal injection of HDGF significantly induced retinal vascular leakage. These results suggest that HDGF is an angiogenic factor that regulates retinal vasculature in physiologic and pathological conditions. Identification of HDGF by ligandomics and its independent characterization in this study also support the validity of this new technology for systematic

  3. The regulatory role of hepatoma-derived growth factor as an angiogenic factor in the eye

    PubMed Central

    LeBlanc, Michelle E.; Wang, Weiwen; Chen, Xiuping; Ji, Yanli; Shakya, Akhalesh; Shen, Chen; Zhang, Chenming; Gonzalez, Vivianne; Brewer, Megan; Ma, Jian-xing; Wen, Rong; Zhang, Fangliang

    2016-01-01

    Purpose Hepatoma-derived growth factor (HDGF) is a mitogen that promotes endothelial proliferation and neuronal survival. Using a unique technology of ligandomics, we recently identified HDGF as a retinal endothelial binding protein. The purpose of this study is to examine the role of HDGF in regulating ocular vasculature and the expression of HDGF in the retina. Methods HDGF expression in the retinal was analyzed with western blot and immunohistochemistry. Angiogenic activity was investigated in human retinal microvascular endothelial cells (HRMVECs) with in vitro endothelial proliferation, migration, and permeability assays. In vivo angiogenic activity was quantified with a corneal pocket assay. The Evans blue assay and western blot using anti-mouse albumin were performed to detect the capacity of HDGF to induce retinal vascular leakage. Results Immunohistochemistry revealed that HDGF is expressed in the retina with a distinct pattern. HDGF was detected in retinal ganglion cells and the inner nuclear layer but not in the inner plexiform layer, suggesting that HDGF is expressed in the nucleus, but not in the cytoplasm, of retinal neurons. In contrast to family member HDGF-related protein 3 (HRP-3) that has no expression in photoreceptors, HDGF is also present in the outer nuclear layer and the inner and outer segments of photoreceptors. This suggests that HDGF is expressed in the nucleus as well as the cytoplasm of photoreceptors. In vitro functional assays showed that HDGF induced the proliferation, migration, and permeability of HRMVECs. Corneal pocket assay indicated that HDGF directly stimulated angiogenesis in vivo. Intravitreal injection of HDGF significantly induced retinal vascular leakage. Conclusions These results suggest that HDGF is an angiogenic factor that regulates retinal vasculature in physiologic and pathological conditions. Identification of HDGF by ligandomics and its independent characterization in this study also support the validity of this

  4. Hepatoma-derived growth factor: from the bovine uterus to the in vitro embryo culture.

    PubMed

    Gómez, E; Correia-Álvarez, E; Caamaño, J N; Díez, C; Carrocera, S; Peynot, N; Martín, D; Giraud-Delville, C; Duranthon, V; Sandra, O; Muñoz, M

    2014-10-01

    Early in cow embryo development, hepatoma-derived growth factor (HDGF) is detectable in uterine fluid. The origin of HDGF in maternal tissues is unknown, as is the effect of the induction on developing embryos. Herein, we analyze HDGF expression in day 8 endometrium exposed to embryos, as well as the effects of recombinant HDGF (rHDGF) on embryo growth. Exposure to embryos did not alter endometrial levels of HDGF mRNA or protein. HDGF protein localized to cell nuclei in the luminal epithelium and superficial glands and to the apical cytoplasm in deep glands. After uterine passage, levels of embryonic HDGF mRNA decreased and HDGF protein was detected only in the trophectoderm. In fetal fibroblast cultures, addition of rHDGF promoted cell proliferation. In experiments with group cultures of morulae in protein-free medium containing polyvinyl alcohol, adding rHDGF inhibited blastocyst development and did not affect cell counts when the morulae were early (day 5), whereas it enhanced blastocyst development and increased cell counts when the morulae were compact (day 6). In cultures of individual day 6 morulae, adding rHDGF promoted blastocyst development and increased cell counts. Our experiments with rHDGF indicate that the growth factor stimulates embryonic development and cell proliferation. HDGF is synthesized similarly by the endometrium and embryo, and it may exert embryotropic effects by autocrine and/or paracrine mechanisms.

  5. 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.

  6. Hepatoma-derived growth factor-related protein 2 promotes DNA repair by homologous recombination

    PubMed Central

    Baude, Annika; Aaes, Tania Løve; Zhai, Beibei; Al-Nakouzi, Nader; Oo, Htoo Zarni; Daugaard, Mads; Rohde, Mikkel; Jäättelä, Marja

    2016-01-01

    We have recently identified lens epithelium-derived growth factor (LEDGF/p75, also known as PSIP1) as a component of the homologous recombination DNA repair machinery. Through its Pro-Trp-Trp-Pro (PWWP) domain, LEDGF/p75 binds to histone marks associated with active transcription and promotes DNA end resection by recruiting DNA endonuclease retinoblastoma-binding protein 8 (RBBP8/CtIP) to broken DNA ends. Here we show that the structurally related PWWP domain-containing protein, hepatoma-derived growth factor-related protein 2 (HDGFRP2), serves a similar function in homologous recombination repair. Its depletion compromises the survival of human U2OS osteosarcoma and HeLa cervix carcinoma cells and impairs the DNA damage-induced phosphorylation of replication protein A2 (RPA2) and the recruitment of DNA endonuclease RBBP8/CtIP to DNA double strand breaks. In contrast to LEDGF/p75, HDGFRP2 binds preferentially to histone marks characteristic for transcriptionally silent chromatin. Accordingly, HDGFRP2 is found in complex with the heterochromatin-binding chromobox homologue 1 (CBX1) and Pogo transposable element with ZNF domain (POGZ). Supporting the functionality of this complex, POGZ-depleted cells show a similar defect in DNA damage-induced RPA2 phosphorylation as HDGFRP2-depleted cells. These data suggest that HDGFRP2, possibly in complex with POGZ, recruits homologous recombination repair machinery to damaged silent genes or to active genes silenced upon DNA damage. PMID:26721387

  7. Circulating auto-antibody against hepatoma-derived growth factor (HDGF) in patients with ulcerative colitis.

    PubMed

    Nahamura, Hideji; Yoshida, Kenya; Kishima, Yoshihiko; Enomoto, Hirayuki; Uyama, Hirokazu; Kuroda, Toshifumi; Okuda, Yorihide; Hirotani, Tomonori; Ito, Hiroaki; Kawase, Ichiro

    2004-01-01

    Various circulating auto-antibodies have been reported in patients with ulcerative colitis. Hepatoma-derived growth factor (HDGF) is a mitogen, localized dominantly in the nucleus of proliferating cells. In this study, we demonstrated the circulating anti-HDGF auto-antibody and investigated its clinical roles in patients with ulcerative colitis. Anti-HDGF IgG antibodies were measured by the enzyme-linked immunosorbent assay with recombinant HDGF in 20 healthy volunteers and 40 patients with ulcerative colitis. Circulating anti-HDGF antibody was detected in the serum of a patient with total colitis by Western blotting. Anti-HDGF auto-antibodies were detected at 65.6% in the serum of patients with total/left-sided colitis, compared with healthy subjects at 10%. During active stage, the circulating anti-HDGF auto-antibodies were detected at a higher frequency of 78.3% than those in remission stage at 37.5%. Furthermore, the titers during active colitis were higher than those during the remission stage. Anti-HDGF auto-antibodies were not detected in any patients with proctitis. These findings suggest that anti-HDGF auto-antibodies in the serum of patients with ulcerative colitis would help to classify the total/left-sided colitis from proctitis, and the serial measurement of the titer would also be a good marker for the active colitis.

  8. Hepatoma-derived growth factor regulates breast cancer cell invasion by modulating epithelial--mesenchymal transition.

    PubMed

    Chen, San-Cher; Kung, Mei-Lang; Hu, Tsung-Hui; Chen, Hsuan-Yu; Wu, Jian-Ching; Kuo, Hsiao-Mei; Tsai, Han-En; Lin, Yu-Wei; Wen, Zhi-Hong; Liu, Jong-Kang; Yeh, Ming-Hsin; Tai, Ming-Hong

    2012-10-01

    Hepatoma-derived growth factor (HDGF) participates in tumourigenesis but its role in breast cancer is unclear. We set out to elucidate the expression profile and function of HDGF during breast carcinogenesis. Immunoblot and immunohistochemical studies revealed elevated HDGF expression in human breast cancer cell lines and tissues. Nuclear HDGF labelling index was positively correlated with tumour grade, stage and proliferation index, but negatively correlated with survival rate in breast cancer patients. HDGF over-expression was associated with lymph node metastasis and represented an independent prognostic factor for tumour recurrence. Gene transfer studies were performed to elucidate the influence of cellular HDGF level on the malignant behaviour and epithelial-mesenchymal transition (EMT) of breast cancer cells. Adenovirus-mediated HDGF over-expression stimulated the invasiveness and colony formation of MCF-7 cells. Moreover, HDGF over-expression promoted breast cancer cell EMT by E-cadherin down-regulation and vimentin up-regulation. Conversely, HDGF knockdown by RNA interference in MDA-MB-231 cells attenuated the malignant behaviour and elicited EMT reversal by enhancing E-cadherin expression while depleting vimentin expression. Because HDGF is a secreted protein, we evaluated the cellular function of recombinant HDGF and found that exogenously supplied HDGF enhanced the invasiveness of breast cancer cells by down-regulating E-cadherin and up-regulating vimentin at transcriptional and translational levels. In contrast, blockade of HDGF secretion with an HDGF antibody inhibited the malignant behaviours and EMT. Finally, exogenous HDGF partially reversed benzyl isothiocyanate (BITC)-induced EMT suppression. HDGF over-expression may exert a prognostic role for tumour metastasis and recurrence in breast cancer by modulating EMT. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  9. Prognostic value of nuclear hepatoma-derived growth factor (HDGF) localization in patients with breast cancer.

    PubMed

    Chen, Xiaoyan; Yun, Jun; Fei, Fei; Yi, Jun; Tian, Ruifeng; Li, Sanzhong; Gan, Xiaoqiang

    2012-08-15

    Hepatoma-derived growth factor (HDGF) plays an important role in tumor progression. Highly expressed HDGF has been found to indicate poor prognosis in many cancers. However, no information is available regarding the prognostic value of nuclear or cytoplasmic HDGF staining level in breast cancer. In the present study, the nuclear or cytoplasmic HDGF staining level was investigated in 86 patients with primary breast cancer by immunohistochemistry; the relationship between nuclear or cytoplasmic HDGF staining level and clinicopathological parameters was examined by Two-tailed Mann-Whitney U-test or Krustal-Wallis. The prognostic value of nuclear or cytoplasmic HDGF staining level in disease-free survival and overall survival was analyzed by Kaplan-Meier methods and log-rank test. We found that the percentage of cases with strong nuclear HDGF staining level was significantly higher in the cases with high tumor grade, high stage, high proliferation index (Ki-67 index>20%), as well as in those with lymph node invasion and recurrence (p<0.05) compared to those without. No significant correlation was found between cytoplasmic HDGF expression and any clinicopathological variables. In addition, disease-free survival and overall survival were significantly lower in patients with high nuclear HDGF expression (level 2) than in those with low nuclear HDGF expression (level 0 and level 1). Further Cox multivariate analysis showed that high nuclear HDGF expression is an independent factor for indicating poor prognosis in breast cancer patients. No significant difference in disease-free survival rate and overall survival was found between different cytoplasmic HDGF staining levels. All these findings suggest that increased nuclear HDGF expression is involved in tumor progression and might be used as a new prognosticator for breast cancer. Crown Copyright © 2012. Published by Elsevier GmbH. All rights reserved.

  10. Mapping of the gene encoding the human hepatoma-derived growth factor (HDGF) with homology to the high-mobility group (HMG)-1 protein to Xq25

    SciTech Connect

    Wanschura, S.; Bartnitzke, S.; Bullerdiek, J.

    1996-03-01

    This report describes the localization of the human hepatoma-derived growth factor (HDGF) gene to human chromosome Xq25 using fluorescence in situ hybridization. Homology to the high-mobility group (HMG)-1 protein was also demonstrated. 13 refs., 1 fig.

  11. Hepatoma-derived growth factor: A survival-related protein in prostate oncogenesis and a potential target for vitamin K2.

    PubMed

    Shetty, Aditya; Dasari, Subramanyam; Banerjee, Souresh; Gheewala, Taher; Zheng, Guoxing; Chen, Aoshuang; Kajdacsy-Balla, Andre; Bosland, Maarten C; Munirathinam, Gnanasekar

    2016-11-01

    Hepatoma-derived growth factor (HDGF) is a heparin-binding growth factor, which has previously been shown to be expressed in a variety of cancers. HDGF overexpression has also previously been correlated with a poor prognosis in several cancers. The significance of HDGF in prostate cancer, however, has not been investigated. Here, we show that HDGF is overexpressed in both androgen-sensitive LNCaP cells and androgen-insensitive DU145, 22RV1, and PC-3 cells. Forced overexpression enhanced cell viability of RWPE-1 cells, whereas HDGF knockdown reduced cell proliferation in human prostate cancer cells. We also show that HDGF may serve as a survival-related protein as ectopic overexpression of HDGF in RWPE cells up-regulated the expression of antiapoptosis proteins cyclin E and BCL-2, whereas simultaneously down-regulating proapoptotic protein BAX. Western blot analysis also showed that HDGF overexpression modulated the activity of phospho-AKT as well as NF-kB, and these results correlated with in vitro migration and invasion assays. We next assessed the therapeutic potential of HDGF inhibition with a HDGF monoclonal antibody and vitamin k2, showing reduced cell proliferation as well as inhibition of NF-kB expression in HDGF overexpressed RWPE cells treated with a HDGF monoclonal antibody and vitamin K2. Collectively, our results suggest that HDGF is a relevant protein in prostate oncogenesis and may serve as a potential therapeutic target in prostate cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Depletion of hepatoma-derived growth factor-related protein-3 induces apoptotic sensitization of radioresistant A549 cells via reactive oxygen species-dependent p53 activation

    SciTech Connect

    Yun, Hong Shik; Hong, Eun-Hee; Lee, Su-Jae; Baek, Jeong-Hwa; Lee, Chang-Woo; Yim, Ji-Hye; Um, Hong-Duck; Hwang, Sang-Gu

    2013-09-27

    Highlights: •HRP-3 is a radiation- and anticancer drug-responsive protein in A549 cells. •Depletion of HRP-3 induces apoptosis of radio- and chemoresistant A549 cells. •Depletion of HRP-3 promotes ROS generation via inhibition of the Nrf2/HO-1 pathway. •Depletion of HRP-3 enhances ROS-dependent p53 activation and PUMA expression. -- Abstract: Biomarkers based on functional signaling have the potential to provide greater insight into the pathogenesis of cancer and may offer additional targets for anticancer therapeutics. Here, we identified hepatoma-derived growth factor-related protein-3 (HRP-3) as a radioresistance-related gene and characterized the molecular mechanism by which its encoded protein regulates the radio- and chemoresistant phenotype of lung cancer-derived A549 cells. Knockdown of HRP-3 promoted apoptosis of A549 cells and potentiated the apoptosis-inducing action of radio- and chemotherapy. This increase in apoptosis was associated with a substantial generation of reactive oxygen species (ROS) that was attributable to inhibition of the Nrf2/HO-1 antioxidant pathway and resulted in enhanced ROS-dependent p53 activation and p53-dependent expression of PUMA (p53 upregulated modulator of apoptosis). Therefore, the HRP-3/Nrf2/HO-1/ROS/p53/PUMA cascade is an essential feature of the A549 cell phenotype and a potential radiotherapy target, extending the range of targets in multimodal therapies against lung cancer.

  13. Knockdown of hepatoma-derived growth factor-related protein-3 induces apoptosis of H1299 cells via ROS-dependent and p53-independent NF-κB activation.

    PubMed

    Yun, Hong Shik; Baek, Jeong-Hwa; Yim, Ji-Hye; Lee, Su-Jae; Lee, Chang-Woo; Song, Jie-Young; Um, Hong-Duck; Park, Jong Kuk; Park, In-Chul; Hwang, Sang-Gu

    2014-07-11

    We previously identified hepatoma-derived growth factor-related protein-3 (HRP-3) as a radioresistant biomarker in p53 wild-type A549 cells and found that p53-dependent induction of the PUMA pathway was a critical event in regulating the radioresistant phenotype. Here, we found that HRP-3 knockdown regulates the radioresistance of p53-null H1299 cells through a distinctly different molecular mechanism. HRP-3 depletion was sufficient to cause apoptosis of H1299 cells by generating substantial levels of reactive oxygen species (ROS) through inhibition of the Nrf2/HO-1 antioxidant pathway. Subsequent, ROS-dependent and p53-independent NF-κB activation stimulated expression of c-Myc and Noxa proteins, thereby inducing the apoptotic machinery. Our results thus extend the range of targets for the development of new drugs to treat both p53 wild-type or p53-null radioresistant lung cancer cells.

  14. Knockdown of hepatoma-derived growth factor-related protein-3 induces apoptosis of H1299 cells via ROS-dependent and p53-independent NF-κB activation

    SciTech Connect

    Yun, Hong Shik; Baek, Jeong-Hwa; Yim, Ji-Hye; Lee, Su-Jae; Lee, Chang-Woo; Song, Jie-Young; Um, Hong-Duck; Park, Jong Kuk; Park, In-Chul; Hwang, Sang-Gu

    2014-07-11

    Highlights: • HRP-3 is a radiation- and anticancer drug-responsive protein in H1299 cells. • Depletion of HRP-3 induces apoptosis of radio- and chemoresistant H1299 cells. • Depletion of HRP-3 promotes ROS generation via inhibition of the Nrf2/HO-1 pathway. • ROS generation enhances NF-κB activity, which acts as an upstream signal in the c-Myc/Noxa apoptotic pathway. - Abstract: We previously identified hepatoma-derived growth factor-related protein-3 (HRP-3) as a radioresistant biomarker in p53 wild-type A549 cells and found that p53-dependent induction of the PUMA pathway was a critical event in regulating the radioresistant phenotype. Here, we found that HRP-3 knockdown regulates the radioresistance of p53-null H1299 cells through a distinctly different molecular mechanism. HRP-3 depletion was sufficient to cause apoptosis of H1299 cells by generating substantial levels of reactive oxygen species (ROS) through inhibition of the Nrf2/HO-1 antioxidant pathway. Subsequent, ROS-dependent and p53-independent NF-κB activation stimulated expression of c-Myc and Noxa proteins, thereby inducing the apoptotic machinery. Our results thus extend the range of targets for the development of new drugs to treat both p53 wild-type or p53-null radioresistant lung cancer cells.

  15. Hepatoma-derived growth factor: Protein quantification in uterine fluid, gene expression in endometrial-cell culture and effects on in vitro embryo development, pregnancy and birth.

    PubMed

    Gómez, E; Carrocera, S; Martin, D; Sánchez-Calabuig, M J; Gutiérrez-Adán, A; Murillo, A; Muñoz, M

    2017-07-01

    Hepatoma-derived growth factor (HDGF) is present in the endometrium of cows and other mammals. Recombinant HDGF (rHDGF) improves bovine blastocyst development in vitro. However, specific culture conditions and essential aspects of HDGF uterine physiology are yet unknown. In this work we quantified total HDGF protein in uterine fluid (UF) by multiple reaction monitoring (MRM), and analyzed effects of rHDGF on specific embryonic stages with Day-6 bovine embryos cultured in vitro with and without BSA, and on pregnancy viability and calf phenotypes after embryo transfer to recipients. In addition, mRNA abundance of HDGF in endometrial cells co-cultured with one male or one female embryo was quantified. In the presence of BSA, rHDGF had no effect on blastocyst development; however, in BSA-free culture rHDGF mainly promoted development of early blastocysts in contrast with morulae. As the presence of HDGF contained in commercial BSA replacements was suspected, western blot confirmed HDGF identification in BSA both with and without fatty acids. Total HDGF quantified by MRM tended to increase in UF without vs. UF with embryos (P = 0.083). Pregnancy and birth rates, birth weight and calf measurements did not differ between embryos cultured with rHDGF and controls without rHDGF. However, HDGF abundance in cultured epithelial, endometrial cells tended to increase (P < 0.08) in culture with one male embryo. rHDGF acts selectively on specific embryonic stages, but care should be taken with specific macromolecular supplements in culture. The endometrial expression of HDGF can be regulated by the embryonic sex. The use of rHDGF is compatible with pregnancy and birth of normal calves. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. An endothelial growth factor involved in rat renal development.

    PubMed Central

    Oliver, J A; Al-Awqati, Q

    1998-01-01

    In the kidney, there is a close and intricate association between epithelial and endothelial cells, suggesting that a complex reciprocal interaction may exist between these two cell types during renal ontogeny. Thus, we examined whether metanephrogenic mesenchymal cells secrete endothelial mitogens. With an endothelial mitogenic assay and sequential chromatography of the proteins in the media conditioned by a cell line of rat metanephrogenic mesenchymal cells (7.1.1 cells), we isolated a protein whose amino acid analysis identified it as hepatoma-derived growth factor (HDGF). Media conditioned with Cos-7 cell transfected with HDGF cDNA stimulated endothelial DNA synthesis. With immunoaffinity purified antipeptide antibodies, we found that HDGF was widely distributed in the renal anlage at early stages of development but soon concentrated at sites of active morphogenesis and, except for some renal tubules, disappeared from the adult kidney. From a 7.1.1 cells cDNA library, a clone of most of the translatable region of HDGF was obtained and used to synthesize digoxigenin-labeled riboprobes. In situ hybridization showed that during kidney development mRNA for HDGF was most abundant at sites of nephron morphogenesis and in ureteric bud cells while in the adult kidney transcripts disappeared except for a small population of distal tubules. Thus, HDGF is an endothelial mitogen that is present in embryonic kidney, and its expression is synchronous with nephrogenesis. PMID:9739055

  17. Neutral red uptake inhibition in adhered and adhering rat hepatoma-derived Fa32 cells to predict human toxicity.

    PubMed

    Dierickx, Paul J; Scheers, Ellen M

    2002-01-01

    The cytotoxicity of the MEIC (Multicentre Evaluation of In vitro Cytotoxicity) reference chemicals was investigated by measuring the neutral red uptake inhibition in adhered and adhering rat hepatoma-derived Fa32 cells. The adhered cells were seeded and then treated and the adhering cells were treated simultaneously upon seeding. Five of the 44 test chemicals were twofold more toxic in adhering cells; ethylene glycol was 28-fold more toxic and mercuric chloride was 5.2-fold more toxic than in adhered cells. The cytotoxicity of dithiothreitol was altered in the same way as that of ethylene glycol, probably by interacting with calcium. When the neutral red uptake inhibition was compared with human toxicity, the correlation coefficient for adhering cells was almost identical to that obtained previously in human hepatoma-derived Hep G2 cells and slightly higher for adhered cells. The Hep G2 assay was the best acute in vitro assay for the prediction of human toxicity within the MEIC study. An obviously better correlation was obtained when the strong intoxicant mercuric chloride was withdrawn from the comparison, both for the adhered and the adhering cells. Altogether, the results can be integrated very well with the basal cytotoxicity concept.

  18. Factors affecting bone growth.

    PubMed

    Gkiatas, Ioannis; Lykissas, Marios; Kostas-Agnantis, Ioannis; Korompilias, Anastasios; Batistatou, Anna; Beris, Alexandros

    2015-02-01

    Bone growth and development are products of the complex interactions of genetic and environmental factors. Longitudinal bone growth depends on the growth plate. The growth plate has 5 different zones-each with a different functional role-and is the final target organ for longitudinal growth. Bone length is affected by several systemic, local, and mechanical factors. All these regulation systems control the final length of bones in a complicated way. Despite its significance to bone stability, bone growth in width has not been studied as extensively as longitudinal bone growth. Bone growth in width is also controlled by genetic factors, but mechanical loading regulates periosteal apposition. In this article, we review the most recent data regarding bone growth from the embryonic age and analyze the factors that control bone growth. An understanding of this complex system is important in identifying metabolic and developmental bone diseases and fracture risk.

  19. Human papillomavirus type 18 E6 and E7 genes integrate into human hepatoma derived cell line Hep G2.

    PubMed

    Ma, Tianzhong; Su, Zhongjing; Chen, Ling; Liu, Shuyan; Zhu, Ningxia; Wen, Lifeng; Yuan, Yan; Lv, Leili; Chen, Xiancai; Huang, Jianmin; Chen, Haibin

    2012-01-01

    Human papillomaviruses have been linked causally to some human cancers such as cervical carcinoma, but there is very little research addressing the effect of HPV infection on human liver cells. We chose the human hepatoma derived cell line Hep G2 to investigate whether HPV gene integration took place in liver cells as well. We applied PCR to detect the possible integration of HPV genes in Hep G2 cells. We also investigated the expression of the integrated E6 and E7 genes by using RT-PCR and Western blotting. Then, we silenced E6 and E7 expression and checked the cell proliferation and apoptosis in Hep G2 cells. Furthermore, we analyzed the potential genes involved in cell cycle and apoptosis regulatory pathways. Finally, we used in situ hybridization to detect HPV 16/18 in hepatocellular carcinoma samples. Hep G2 cell line contains integrated HPV 18 DNA, leading to the expression of the E6 and E7 oncogenic proteins. Knockdown of the E7 and E6 genes expression reduced cell proliferation, caused the cell cycle arrest at the S phase, and increased apoptosis. The human cell cycle and apoptosis real-time PCR arrays analysis demonstrated E6 and E7-mediated regulation of some genes such as Cyclin H, UBA1, E2F4, p53, p107, FASLG, NOL3 and CASP14. HPV16/18 was found in only 9% (9/100) of patients with hepatocellular carcinoma. Our investigations showed that HPV 18 E6 and E7 genes can be integrated into the Hep G2, and we observed a low prevalence of HPV 16/18 in hepatocellular carcinoma samples. However, the precise risk of HPV as causative agent of hepatocellular carcinoma needs further study.

  20. 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.

  1. 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.

  2. Peptide growth factors, part A

    SciTech Connect

    Barnes, D.; Sirbasku, D.A.

    1987-01-01

    This book contains information on the following topics: Epidermal Growth Factor;Transforming Growth Factors;Bone and Cartilage Growth Factors;Somatomedin/Insulin-Like Growth Factors;Techniques for the Study of Growth Factor Activity;Assays, Phosphorylation, and Surface Membrane Effects.

  3. New microbial growth factor.

    PubMed Central

    Bok, S H; Casida, L E

    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 new 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 it 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. PMID:327929

  4. 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.

  5. 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.

  6. [Fibroblast growth factor-2].

    PubMed

    Faitová, J

    2004-01-01

    Fibroblast growth factor-2 is a member of a large family of proteins that bind heparin and heparan sulfate and modulate the function of a wide range of cell types. FGF-2 occurs in several isoforms resulting from alternative initiations of traslation: an 18 kDa cytoplasmic isoform and four larger molecular weight nuclear isoforms (22, 22.5, 24 and 34 kDa). It acts mainly through a paracrine/autocrine mechanism involving high affinity transmembrane receptors and heparan sulfate proteoglycan low affinity receptors. It is expressed mostly in tissues of mesoderm and neuroectoderm origin, and plays an important role in mesoderm induction, stimulates the growth and development of the new blood vessels (angiogenesis), normal wound healing and tissue development. FGF-2 positively regulates hematopoiesis by acting on various cellular targets: stromal cells, early and committed hematopoietic progenitors and possibly some mature blood cells. FGF-2 is a potent hematopoietic growth factor that is likely to play an important role in physiological and pathological hematopoiesis.

  7. Sulphation of proteins secreted by a human hepatoma-derived cell line. Sulphation of N-linked oligosaccharides on alpha 2HS-glycoprotein.

    PubMed Central

    Hortin, G; Green, E D; Baenziger, J U; Strauss, A W

    1986-01-01

    Several human glycoproteins, including alpha 1-antitrypsin, alpha 1-acid glycoprotein, transferrin, caeruloplasmin and alpha 2HS-glycoprotein, synthesized by the hepatoma-derived cell line HepG2 were observed to contain covalently linked sulphate. These proteins were estimated to contain about 0.1 mol of sulphate/mol of protein. The most abundant of the sulphated glycoproteins, alpha 2HS-glycoprotein, was analysed in detail. All of the sulphate on this protein was attached to N-linked oligosaccharides which contained sialic acid and resisted release by endoglycosidase H. Several independent analytical approaches established that approx. 10% of the molecules of alpha 2HS-glycoprotein contained sulphate. Our results suggest that a number of human plasma proteins contain small amounts of sulphate linked to oligosaccharides. Images Fig. 1. Fig. 2. Fig. 3. PMID:3017304

  8. Growth hormone, growth factors, and acromegaly

    SciTech Connect

    Ludecke, D.K.; Tolis, G.T.

    1987-01-01

    This book contains five sections, each consisting of several papers. The section headings are: Biochemistry and Physiology of GH and Growth Factors, Pathology of Acromegaly, Clinical Endocrinology of Acromegaly, Nonsurgical Therapy of Acromegaly, and Surgical Therapy of Acromegaly.

  9. Inversely repeating integrated hepatitis B virus DNA and cellular flanking sequences in the human hepatoma-derived cell line huSP.

    PubMed Central

    Mizusawa, H; Taira, M; Yaginuma, K; Kobayashi, M; Yoshida, E; Koike, K

    1985-01-01

    Among recombinant phages carrying integrated hepatitis B virus (HBV) DNA sequences cloned from the human hepatoma-derived cell line huSP, one clone, lambda hu-489, revealed some unusual features. The 2.25-kilobase Eco D fragment from the insert of this clone hybridized to the HBV DNA probe only and its nucleotide sequence was determined. The viral sequence, as well as a cellular flanking sequence, showed extensive rearrangement accompanied by inverted repetition. The Eco D fragment contained HBV DNA from the 5'-end region of gene S to the middle of gene X, followed by a long cellular flanking sequence. Moreover, a part of gene X was found inversely repeated at the head of the same gene S in a head-to-head configuration truncated by the same cellular sequence. Therefore, the same junction sequence of viral DNA and the cellular sequence was found at two different sites in the Eco D fragment in opposite polarities. Images PMID:2982143

  10. Interstitial fibrosis and growth factors.

    PubMed Central

    Lasky, J A; Brody, A R

    2000-01-01

    Interstitial pulmonary fibrosis (IPF) is scarring of the lung caused by a variety of inhaled agents including mineral particles, organic dusts, and oxidant gases. The disease afflicts millions of individuals worldwide, and there are no effective therapeutic approaches. A major reason for this lack of useful treatments is that few of the molecular mechanisms of disease have been defined sufficiently to design appropriate targets for therapy. Our laboratory has focused on the molecular mechanisms through which three selected peptide growth factors could play a role in the development of IPF. Hundreds of growth factors and cytokines could be involved in the complex disease process. We are studying platelet-derived growth factor because it is the most potent mesenchymal cell mitogen yet described, transforming growth factor beta because it is a powerful inducer of extracellular matrix (scar tissue) components by mesenchymal cells, and tumor necrosis factor alpha because it is a pleiotropic cytokine that we and others have shown is essential for the development of IPF in animal models. This review describes some of the evidence from studies in humans, in animal models, and in vitro, that supports the growth factor hypothesis. The use of modern molecular and transgenic technologies could elucidate those targets that will allow effective therapeutic approaches. Images Figure 1 Figure 2 PMID:10931794

  11. Growth factors in synaptic function

    PubMed Central

    Poon, Vivian Y.; Choi, Sojoong; Park, Mikyoung

    2013-01-01

    Synapses are increasingly recognized as key structures that malfunction in disorders like schizophrenia, mental retardation, and neurodegenerative diseases. The importance and complexity of the synapse has fuelled research into the molecular mechanisms underlying synaptogenesis, synaptic transmission, and plasticity. In this regard, neurotrophic factors such as netrin, Wnt, transforming growth factor-β (TGF-β), tumor necrosis factor-α (TNF-α), and others have gained prominence for their ability to regulate synaptic function. Several of these factors were first implicated in neuroprotection, neuronal growth, and axon guidance. However, their roles in synaptic development and function have become increasingly clear, and the downstream signaling pathways employed by these factors have begun to be elucidated. In this review, we will address the role of these factors and their downstream effectors in synaptic function in vivo and in cultured neurons. PMID:24065916

  12. CYP1A1 and CYP1A2 expression: Comparing 'humanized' mouse lines and wild-type mice; comparing human and mouse hepatoma-derived cell lines

    SciTech Connect

    Uno, Shigeyuki; Endo, Kaori; Ishida, Yuji; Tateno, Chise; Makishima, Makoto; Yoshizato, Katsutoshi; Nebert, Daniel W.

    2009-05-15

    Human and rodent cytochrome P450 (CYP) enzymes sometimes exhibit striking species-specific differences in substrate preference and rate of metabolism. Human risk assessment of CYP substrates might therefore best be evaluated in the intact mouse by replacing mouse Cyp genes with human CYP orthologs; however, how 'human-like' can human gene expression be expected in mouse tissues? Previously a bacterial-artificial-chromosome-transgenic mouse, carrying the human CYP1A1{sub C}YP1A2 locus and lacking the mouse Cyp1a1 and Cyp1a2 orthologs, was shown to express robustly human dioxin-inducible CYP1A1 and basal versus inducible CYP1A2 (mRNAs, proteins, enzyme activities) in each of nine mouse tissues examined. Chimeric mice carrying humanized liver have also been generated, by transplanting human hepatocytes into a urokinase-type plasminogen activator(+/+){sub s}evere-combined-immunodeficiency (uPA/SCID) line with most of its mouse hepatocytes ablated. Herein we compare basal and dioxin-induced CYP1A mRNA copy numbers, protein levels, and four enzymes (benzo[a]pyrene hydroxylase, ethoxyresorufin O-deethylase, acetanilide 4-hydroxylase, methoxyresorufin O-demethylase) in liver of these two humanized mouse lines versus wild-type mice; we also compare these same parameters in mouse Hepa-1c1c7 and human HepG2 hepatoma-derived established cell lines. Most strikingly, mouse liver CYP1A1-specific enzyme activities are between 38- and 170-fold higher than human CYP1A1-specific enzyme activities (per unit of mRNA), whereas mouse versus human CYP1A2 enzyme activities (per unit of mRNA) are within 2.5-fold of one another. Moreover, both the mouse and human hepatoma cell lines exhibit striking differences in CYP1A mRNA levels and enzyme activities. These findings are relevant to risk assessment involving human CYP1A1 and CYP1A2 substrates, when administered to mice as environmental toxicants or drugs.

  13. Physiological factors influencing capillary growth.

    PubMed

    Egginton, S

    2011-07-01

    (1) Angiogenesis (growth of new capillaries from an existing capillary bed) may result from a mismatch in microvascular supply and metabolic demand (metabolic error signal). Krogh examined the distribution and number of capillaries to explore the correlation between O(2) delivery and O(2) consumption. Subsequently, the heterogeneity in angiogenic response within a muscle has been shown to reflect either differences in fibre type composition or mechanical load. However, local control leads to targetted angiogenesis in the vicinity of glycolytic fibre types following muscle stimulation, or oxidative fibres following endurance training, while heterogeneity of capillary spacing is maintained during ontogenetic growth. (2) Despite limited microscopy resolution and lack of specific markers, Krogh's interest in the structure of the capillary wall paved the way for understanding the mechanisms of capillary growth. Angiogenesis may be influenced by the response of perivascular or stromal cells (fibroblasts, macrophages and pericytes) to altered activity, likely acting as a source for chemical signals modulating capillary growth such as vascular endothelial growth factor. In addition, haemodynamic factors such as shear stress and muscle stretch play a significant role in adaptive remodelling of the microcirculation. (3) Most indices of capillarity are highly dependent on fibre size, resulting in possible bias because of scaling. To examine the consequences of capillary distribution, it is therefore helpful to quantify the area of tissue supplied by individual capillaries. This allows the spatial limitations inherent in most models of tissue oxygenation to be overcome generating an alternative approach to Krogh's tissue cylinder, the capillary domain, to improve descriptions of intracellular oxygen diffusion. © 2010 The Author. Acta Physiologica © 2010 Scandinavian Physiological Society.

  14. [Neuronal growth factors--neurotrophins].

    PubMed

    Meyer, M; Rasmussen, J Z

    1999-04-05

    Neurotrophic factors are polypeptides primarily known to regulate the survival and differentiation of nerve cells during the development of the peripheral and central nervous systems. The neurotrophic factors act via specific receptors after retrograde axonal transport from the nerve fibre target areas back to the cell bodies, and locally through autocrine and paracrine mechanisms linked to nerve cell activity. In the mature nervous system, neurotrophic factors maintain morphological and neurochemical characteristics of nerve cells and promote activity-dependent dynamic/plastic changes in the synaptic contacts between nerve cells by strengthening functionally active synaptic connections. Induction and increased production of neurotrophic factors in relation to neural injuries are thought to serve protective and reparative purposes. Specific neurotrophic factors have thus been shown to protect nerve cells in a number of experimental models for neurodegenerative diseases, such as Parkinson disease, Alzheimer disease, and amyotrophic lateral sclerosis, just as specific neurotrophic factors have been shown to stimulate regenerative growth of both peripheral and central nerve fibres. Today, problems with continuous and localized delivery of specific neurotrophins or combinations thereof into the nervous system appear to be the most important obstacle for more widespread clinical application.

  15. Growth and growth factors in diabetes mellitus.

    PubMed Central

    Salardi, S; Tonioli, S; Tassoni, P; Tellarini, M; Mazzanti, L; Cacciari, E

    1987-01-01

    Growth of 79 children with diabetes was analysed at diagnosis and again after one to 10.7 years of treatment with insulin. Both sexes were tall at onset, whereas at the last observation boys alone showed significant growth retardation. Height standard deviation score (SDS), however, showed no significant fall either in 32 subjects reassessed after five years of disease or in 18 subjects examined at full stature. Skeletal maturity was not significantly impaired after treatment. Pubertal growth spurt was reduced, especially in girls and in subjects with onset of disease at or around puberty. We found no significant correlation between height and height velocity SDS and glycosylated haemoglobin values or secretion of growth hormone during the arginine test. Somatomedin C values were correlated with height velocity SDS in prepubertal boys. The results of this study suggest that there are interferences in the growth of children with diabetes but that they do not seem to have a significant influence on adult height. PMID:3813637

  16. 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.

  17. Growth Factors in Proliferative Diabetic Retinopathy

    PubMed Central

    Khan, Zia Ali

    2003-01-01

    Many growth factors are implicated in the pathogenesis of proliferative diabetic retinopathy. Alteration of growth factors and their receptors in diabetes has been shown in both experimental and clinical studies. Sustained hyperglycemia resulting from long-standing diabetes leads to several biochemical abnormalities that consequently result in retinal hypoxia. Retinal oxygenation state regulates various growth factors that promote angiogenesis in order to meet the oxygen demands of the tissue. However, unregulated expression of these growth factors and induction of complex cascades leading to augmentation of other proangiogenic factors, which may not be regulated by tissue oxygenation, leads to uncontrolled retinal neovascularization and blindness in diabetic patients. PMID:14668050

  18. Growth factors and acute renal failure.

    PubMed

    Hirschberg, R; Ding, H

    1998-03-01

    During acute renal injury, there are alterations in the expression of several growth factors and their receptors in the kidney. The increased expression of several growth factors and/or their receptors at sites of nephron injury suggests important contributions to repair. Exogenous administration of some growth factors, such as IGF-I, EGF and HGF, accelerates recovery of renal function in experimental acute renal failure (ARF). In ARF growth factors act through several mechanisms, which may include altered cell cycle regulation and mitogenesis, differentiation of recovered cells, regulation of apoptosis, improved renal hemodynamics, and others. There is evidence for interactions of growth factors with other growth factors as well as with other genes resulting in complex orchestration of biologic events contributing to recovery from ARF.

  19. 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.

  20. 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

  1. Autocrine growth factors and solid tumor malignancy.

    PubMed Central

    Walsh, J. H.; Karnes, W. E.; Cuttitta, F.; Walker, A.

    1991-01-01

    The ability of malignant cells to escape the constraint that normally regulate cell growth and differentiation has been a primary focus of attention for investigators of cancer cell biology. An outcome of this attention has been the discovery that the protein products of oncogenes play a role in the activation of growth signal pathways. A second outcome, possibly related to abnormal oncogene expression, has been the discovery that malignant cells frequently show an ability to regulate their own growth by the release of autocrine growth modulatory substances. Most important, the growth of certain malignant cell types has been shown to depend on autocrine growth circuits. A malignant tumor whose continued growth depends on the release of an autocrine growth factor may be vulnerable to treatment with specific receptor antagonists or immunoneutralizing antibodies designed to break the autocrine circuit. Information is rapidly emerging concerning autocrine growth factors in selected human solid tissue malignancy. Images PMID:1926844

  2. 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.

  3. Roles for Growth Factors in Cancer Progression

    PubMed Central

    Witsch, Esther; Sela, Michael; Yarden, Yosef

    2011-01-01

    Under physiological conditions, cells receive fate-determining signals from their tissue surroundings, primarily in the form of polypeptide growth factors. Integration of these extracellular signals underlies tissue homeostasis. Although departure from homeostasis and tumor initiation are instigated by oncogenic mutations rather than by growth factors, the latter are the major regulators of all subsequent steps of tumor progression, namely clonal expansion, invasion across tissue barriers, angiogenesis, and colonization of distant niches. Here, we discuss the relevant growth factor families, their roles in tumor biology, as well as the respective downstream signaling pathways. Importantly, cancer-associated activating mutations that impinge on these pathways often relieve, in part, the reliance of tumors on growth factors. On the other hand, growth factors are frequently involved in evolvement of resistance to therapeutic regimens, which extends the roles for polypeptide factors to very late phases of tumor progression and offers opportunities for cancer therapy. PMID:20430953

  4. Growth factor gene therapy for Alzheimer disease.

    PubMed

    Tuszynski, Mark H; U, Hoi Sang; Alksne, John; Bakay, Roy A; Pay, Mary Margaret; Merrill, David; Thal, Leon J

    2002-11-15

    The capacity to prevent neuronal degeneration and death during the course of progressive neurological disorders such as Alzheimer disease (AD) would represent a significant advance in therapy. Nervous system growth factors are families of naturally produced proteins that, in animal models, exhibit extensive potency in preventing neuronal death due to a variety of causes, reversing age-related atrophy of neurons, and ameliorating functional deficits. The main challenge in translating growth factor therapy to the clinic has been delivery of growth factors to the brain in sufficient concentrations to influence neuronal function. One means of achieving growth factor delivery to the central nervous system in a highly targeted, effective manner may be gene therapy. In this article the authors summarize the development and implementation of nerve growth factor gene delivery as a potential means of reducing cell loss in AD.

  5. Growth factors from genes to clinical application

    SciTech Connect

    Sara, V.R. ); Hall, K.; Low, H. )

    1990-01-01

    The last decade has witnessed an explosion in the identification of growth factors and their receptors. This has been greatly facilitated by recombinant DNA technology, which has provided the tools not only to identify these proteins at the gene level but also to produce recombinant proteins for evaluating their biological activities. With the help of such techniques, we are moving toward an understanding of the biosynthesis of growth factors and their receptors, structure-function relationships, as well as mechanisms for intracellular signal transmission. The possibility of modifying these factors has opened new fields of clinical application. In this paper, four major areas of growth factor research are presented: the characterization of growth factor genes and their protein products, growth factor receptors and signal transduction by the receptors to mediate biological action, the biological actions of the various growth factors, and the role of growth factors in health and disease and their possible clinical application. Some of the topics covered include: structure of the IGFs and their variants; isoforms of PDGF receptor types; tyrosine kinase activation; structure of G-proteins in biological membranes; possible therapeutic application of NGF in the treatment of Parkinson's and Alzheimer's diseases; PDGF's possible role in the development of several fibroproliferative diseases and its therapeutic application in wound healing; and the possible use of angiogenic inhibitors in tumor treatment.

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

    PubMed

    Stoĭka, R S

    1988-01-01

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

  7. Growth factors for the treatment of ischemic brain injury (growth factor treatment).

    PubMed

    Larpthaveesarp, Amara; Ferriero, Donna M; Gonzalez, Fernando F

    2015-04-30

    In recent years, growth factor therapy has emerged as a potential treatment for ischemic brain injury. The efficacy of therapies that either directly introduce or stimulate local production of growth factors and their receptors in damaged brain tissue has been tested in a multitude of models for different Central Nervous System (CNS) diseases. These growth factors include erythropoietin (EPO), vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), and insulin-like growth factor (IGF-1), among others. Despite the promise shown in animal models, the particular growth factors that should be used to maximize both brain protection and repair, and the therapeutic critical period, are not well defined. We will review current pre-clinical and clinical evidence for growth factor therapies in treating different causes of brain injury, as well as issues to be addressed prior to application in humans.

  8. 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.

  9. Angiogenic growth factors in preinvasive breast disease.

    PubMed

    Heffelfinger, S C; Miller, M A; Yassin, R; Gear, R

    1999-10-01

    Recently, we showed that preinvasive breast pathologies, such as usual hyperplasia, atypical hyperplasia, and carcinoma in situ, have an increased vascularity when compared with normal breast tissue (S. C. Heffelfinger et al., Clinical Cancer Res., 2: 1873-1878, 1996). To understand the mechanism of this increased vascularity, we examined by immunohistochemistry each of these pathological lesions for the expression of angiogenic growth factors. These studies showed that normal breast tissue contains numerous angiogenic agents, particularly vascular endothelial cell growth factor and basic fibroblast growth factor. At the transition from normal epithelium to proliferative breast disease, insulin-like growth factor (IGF) II expression was increased, primarily in the stroma and infiltrating leukocytes. However, among proliferative tissues, IGF I decreased with increasing vascularity. Finally, both epithelial vascular endothelial growth factor and epithelial and leukocytic platelet-derived endothelial cell growth factor increased at the transition to carcinoma in situ, whereas stromal and leukocytic basic fibroblast growth factor were elevated only in invasive carcinoma. Therefore, during histological progression there is also a complex progression of angiogenic growth factors. For CIS, two forms of vascularity are found: stromal microvascular density (MVD), and vascularity associated with the epithelial basement membrane (vascular score). There was 35% discordance between these two measurement systems. Among carcinoma in situ cases, decreases in stromal IGF II were associated with increasing vascular scores but not MVD, and increases in platelet-derived endothelial cell growth factor were associated with increasing MVD but not the vascular score. The presence of discordance and differential association with specific angiogenic agents suggests that these two forms of vascularity may be differentially regulated.

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

    DTIC Science & Technology

    2006-09-01

    Factor for Breast Cancer PRINCIPAL INVESTIGATOR: Larry W. Daniel, Ph.D. CONTRACTING ORGANIZATION: Wake Forest University...A Growth Factor for Breast Cancer 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-04-1-0682 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Larry W...Relevance: If PAF is found to be a growth and angiogenic factor for breast cancer cells, these studies can be followed up by in vivo studies in nude

  11. The role of fibroblast growth factors in tumor growth.

    PubMed

    Korc, M; Friesel, R E

    2009-08-01

    Biological processes that drive cell growth are exciting targets for cancer therapy. The fibroblast growth factor (FGF) signaling network plays a ubiquitous role in normal cell growth, survival, differentiation, and angiogenesis, but has also been implicated in tumor development. Elucidation of the roles and relationships within the diverse FGF family and of their links to tumor growth and progression will be critical in designing new drug therapies to target FGF receptor (FGFR) pathways. Recent studies have shown that FGF can act synergistically with vascular endothelial growth factor (VEGF) to amplify tumor angiogenesis, highlighting that targeting of both the FGF and VEGF pathways may be more efficient in suppressing tumor growth and angiogenesis than targeting either factor alone. In addition, through inducing tumor cell survival, FGF has the potential to overcome chemotherapy resistance highlighting that chemotherapy may be more effective when used in combination with FGF inhibitor therapy. Furthermore, FGFRs have variable activity in promoting angiogenesis, with the FGFR-1 subgroup being associated with tumor progression and the FGFR-2 subgroup being associated with either early tumor development or decreased tumor progression. This review highlights the growing knowledge of FGFs in tumor cell growth and survival, including an overview of FGF intracellular signaling pathways, the role of FGFs in angiogenesis, patterns of FGF and FGFR expression in various tumor types, and the role of FGFs in tumor progression.

  12. An unnatural PIP simulates growth factor signaling.

    PubMed

    Swan, Laura

    2009-11-25

    In this issue of Chemistry & Biology, Laketa et al. describe the synthesis of a membrane permeant phosphoinositide lipid that acts to stimulate PI(3,4,5)P(3)-dependent signaling without the need of growth factor stimulation.

  13. New Clue Found to Growth Factor Action.

    ERIC Educational Resources Information Center

    Hoffman, Michelle

    1991-01-01

    Discussed is the discovery which may help to explain epidermal growth factor effects on the cell skeleton. The role of a protein called profilin in the regulation of the microfilament system is described. (CW)

  14. New Clue Found to Growth Factor Action.

    ERIC Educational Resources Information Center

    Hoffman, Michelle

    1991-01-01

    Discussed is the discovery which may help to explain epidermal growth factor effects on the cell skeleton. The role of a protein called profilin in the regulation of the microfilament system is described. (CW)

  15. The function of vascular endothelial growth factor.

    PubMed

    Nieves, Bonnie J; D'Amore, Patricia A; Bryan, Brad A

    2009-01-01

    Vascular endothelial growth factor (VEGF) is considered the master regulator of angiogenesis during growth and development, as well as in disease states such as cancer, diabetes, and macular degeneration. This review details our current understanding of VEGF signaling and discusses the benefits and unexpected side effects of promising anti-angiogenic therapeutics that are currently being used to inhibit neovacularization in tumors.

  16. Placental growth factor and vascular endothelial growth factor receptor-2 in human lung development.

    PubMed

    Janér, Joakim; Andersson, Sture; Haglund, Caj; Karikoski, Riitta; Lassus, Patrik

    2008-08-01

    We examined the pulmonary expression of 2 proangiogenic factors, namely, placental growth factor and vascular endothelial growth factor receptor-2, during lung development and acute and chronic lung injury in newborn infants. Six groups were included in an immunohistochemical study of placental growth factor and vascular endothelial growth factor receptor-2, that is, 9 fetuses, 4 preterm and 8 term infants without lung injury who died soon after birth, 5 preterm infants with respiratory distress syndrome of <2 days and 7 with respiratory distress syndrome of >10 days, and 6 with bronchopulmonary dysplasia. Placental growth factor concentrations in tracheal aspirate fluid were measured in 70 samples from 20 preterm infants during the first postnatal week. In immunohistochemical analyses, placental growth factor staining was seen in bronchial epithelium and macrophages in all groups. Distal airway epithelium positivity was observed mostly in fetuses and in preterm infants who died soon after birth. Vascular endothelial growth factor receptor-2 staining was seen in vascular endothelium in all groups and also in lymphatic endothelium in fetuses. Vascular endothelial growth factor receptor-2 staining in arterial endothelium was associated with higher and staining in venous endothelium with lower gestational age. In capillaries, less vascular endothelial growth factor receptor-2 staining was seen in bronchopulmonary dysplasia. The mean placental growth factor protein concentration in tracheal aspirate fluid during the first postnatal week was 0.64 +/- 0.42 pg/mL per IgA-secretory component unit. Concentrations during the first postnatal week were stable. Lower placental growth factor concentrations correlated with chorioamnionitis and lactosyl ceramide positivity. The vascular endothelial growth factor receptor-2 staining pattern seems to reflect ongoing differentiation and activity of different endothelia. Lower vascular endothelial growth factor receptor-2 expression

  17. Cancer cells. 3: Growth factors and transformation

    SciTech Connect

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

    1985-01-01

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

  18. 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.

  19. Insulin-like growth factor 1 and hair growth.

    PubMed

    Su, H Y; Hickford, J G; Bickerstaffe, R; Palmer, B R

    1999-11-01

    Insulin-like growth factor 1 (IGF-1) has been identified as an important growth factor in many biological systems.[1] It shares considerable structural homology with insulin and exerts insulin-like effects on food intake and glucose metabolism. Recently it has been suggested to play a role in regulating cellular proliferation and migration during the development of hair follicles. [2,3] To exert its biological effects, the IGF-1 is required to activate cells by binding to specific cell-surface receptors. The type I IGF receptor (IGF-1R) is the only IGF receptor to have IGF-mediated signaling functions.[1] In circulation, this growth factor mediates endocrine action of growth hormone (GH) on somatic growth and is bound to specific binding proteins (BPs). The latter control IGF transport, efflux from vascular compartments and association with cell surface receptors.[4] In tissues, IGF-1 is produced by mesenchymal type cells and acts in a paracrine and autocrine fashion by binding to the IGF-1R. This binding activates the receptor tyrosine kinase (RTK) that triggers the downstream responses and finally stimulates cell division.[5] IGF-1 may therefore be able to stimulate the proliferation of hair follicle cells through cellular signaling pathways of its receptors. Local infusion of IGF-1 into sheep has been reported to be capable of stimulating protein synthesis in the skin.[6] It may also increase the production of wool keratin. Recently, transgenic mice overexpressing IGF-1 in the skin have been shown to have earlier hair follicle development than controls.[7] In addition, this growth factor plays an important role in many cell types as a survival factor to prevent cell death.[8] This anti-apoptotic function of IGF-1 may be important to the development of follicle cells as follicles undergo a growth cycle where the regressive, catagen phase is apoptosis driven. In this review, the effects of IGF-1 on follicle cell proliferation and differentiation are discussed. In

  20. Protein kinase C activators inhibit capillary endothelial cell growth

    SciTech Connect

    Doctrow, S.R.

    1986-05-01

    Phorbol 12,13-dibutyrate (PDBu) binds specifically to bovine capillary endothelial (BCE) cells (K/sub d/ = 8nM) and inhibits the proliferation (K/sub 50/ = 6 +/- 4 nM). Under similar conditions, PDBu does not inhibit the growth of bovine aortic endothelial or smooth muscle cells. PDBu markedly attenuates the response of BCE cells to purified human hepatoma-derived growth factor which, in the absence of PDBu, stimulates BCE cell growth by about 3-fold. Several observations suggest that the inhibition of BCE cell growth by PDBu is mediated by protein kinase C: (1) different phorbol compounds inhibit BCE cell growth according to the relative potencies as protein kinase C activators (12-tetradecanoylphorbol 13-acetate > PDBu >> phorbol 12,13-diacetate >>>..beta..-phorbol; ..cap alpha..-phorbol 12,13-didecanoate). (2) Specific binding of PDBu to BCE cells is displaced by sn-1,2-dioctanoylglycerol (diC/sub 8/), a protein kinase C activator and an analog of the putative second messenger activating this kinase in vivo. The weak protein kinase C activator, sn-1,2-dibutyrylglycerol, does not affect PDBu binding. (3) A cytosolic extract from BCE cells contains a Ca/sup 2 +//phosphatidylserine-dependent kinase that is activated by diC/sub 8/ and PDBu, but not by ..beta..-phorbol. These results support a role for protein kinase C in suppressing capillary endothelial cell growth and may therefore have implications in the intracellular regulation of angiogenesis.

  1. Engineering growth factors for regenerative medicine applications.

    SciTech Connect

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

    2016-01-15

    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 trafficking 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.

  2. 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

  3. FACTORS WHICH CONTROL MAXIMAL GROWTH OF BACTERIA

    PubMed Central

    Sinclair, N. A.; Stokes, J. L.

    1962-01-01

    Sinclair, N. A. (Washington State University, Pullman) and J. L. Stokes. Factors which control maximal growth of bacteria. J. Bacteriol. 83:1147–1154. 1962.—In a chemically defined medium containing 1% glucose and 0.1% (NH4)2SO4, both of these compounds are virtually exhausted by the growth of Pseudomonas fluorescens. If these carbon, energy, and nitrogen sources are added back to the culture filtrate, maximal growth to the level of the original culture is obtained. This process can be repeated several times with the same results. Eventually, however, the supply of minerals in the culture limits growth. When the nutrient levels are raised to 3% glucose and 0.3% (NH4)2SO4, lack of oxygen and low pH limit growth before the supply of nutrients is exhausted. There is no evidence that specific autoinhibitory substances are produced either in chemically defined or complex nitrogenous media or that physical crowding of the cells limits growth. The results with Escherichia coli are similar to those with P. fluorescens. However, after a few growth cycles aerobically and after only one growth cycle anaerobically, inhibitory substances, probably organic acids, accumulate and limit growth. PMID:13913264

  4. PROSPECT - GROWTH FACTOR CONTROL OF BONE MASS

    PubMed Central

    Canalis, Ernesto

    2010-01-01

    Bone formation is determined by the number and function of osteoblasts. Cell number is governed by factors that regulate the replication and differentiation of pre-osteoblasts and factors that regulate osteoblastic cell death. Cell function is controlled by signals acting on the mature osteoblast. Platelet derived and fibroblast growth factors are bone cell mitogens. Bone morphogenetic proteins (BMP) and Wnt induce the differentiation of mesenchymal cells toward osteoblasts, and insulin-like growth factor (IGF)-I stimulates the function of mature osteoblasts and prevents their death. The activity of BMP, Wnt and IGF-I is modulated by extracellular antagonists or binding proteins. Changes in growth factor synthesis and activity may play a role in the pathogenesis of selected forms of osteoporosis, and alterations in the expression or binding of the extracellular antagonists can be associated with changes in bone mass. Current approaches to bone anabolic therapies for osteoporosis include the administration of a growth factor, such as IGF-I, or the neutralization of an antagonist. Ideally, the targeting of an anabolic agent should be specific to bone to preclude non-skeletal unwanted side effects. Clinical trials are needed to determine the long-term effectiveness and safety of novel anabolic agents for the management of osteoporosis. PMID:19718659

  5. Epidermal Growth Factor and Intestinal Barrier Function

    PubMed Central

    Liu, Hu; Yang, Shufen; Li, Zuohua; Zhong, Jinfeng

    2016-01-01

    Epidermal growth factor (EGF) is a 53-amino acid peptide that plays an important role in regulating cell growth, survival, migration, apoptosis, proliferation, and differentiation. In addition, EGF has been established to be an effective intestinal regulator helping to protect intestinal barrier integrity, which was essential for the absorption of nutrients and health in humans and animals. Several researches have demonstrated that EGF via binding to the EGF receptor and subsequent activation of Ras/MAPK, PI3K/AKT, PLC-γ/PKC, and STATS signal pathways regulates intestinal barrier function. In this review, the relationship between epidermal growth factor and intestinal development and intestinal barrier is described, to provide a better understanding of the effects of EGF on intestine development and health. PMID:27524860

  6. Role of hematopoietic growth factors in angiogenesis.

    PubMed

    Ribatti, D; Vacca, A; De Falco, G; Ria, R; Roncali, L; Dammacco, F

    2001-01-01

    In early ontogeny, hematopoiesis is closely associated with angiogenesis. This article reviews recent studies of the effect of hematopoietic growth factors on several endothelial cell functions together with recent findings about angiogenesis and antiangiogenic therapies in hematopoietic malignancies such as leukemia, lymphoma and myeloma. Copyright 2001 S. Karger AG, Basel

  7. Nerve Growth Factor and Diabetic Neuropathy

    PubMed Central

    Vinik, Aaron

    2003-01-01

    Neuropathy is one of the most debilitating complications of both type 1 and type 2 diabetes, with estimates of prevalence between 50–90% depending on the means of detection. Diabetic neuropathies are heterogeneous and there is variable involvement of large myelinated fibers and small, thinly myelinated fibers. Many of the neuronal abnormalities in diabetes can be duplicated by experimental depletion of specific neurotrophic factors, their receptors or their binding proteins. In experimental models of diabetes there is a reduction in the availability of these growth factors, which may be a consequence of metabolic abnormalities, or may be independent of glycemic control. These neurotrophic factors are required for the maintenance of the neurons, the ability to resist apoptosis and regenerative capacity. The best studied of the neurotrophic factors is nerve growth factor (NGF) and the related members of the neurotrophin family of peptides. There is increasing evidence that there is a deficiency of NGF in diabetes, as well as the dependent neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) that may also contribute to the clinical symptoms resulting from small fiber dysfunction. Similarly, NT3 appears to be important for large fiber and IGFs for autonomic neuropathy. Whether the observed growth factor deficiencies are due to decreased synthesis, or functional, e.g. an inability to bind to their receptor, and/or abnormalities in nerve transport and processing, remains to be established. Although early studies in humans on the role of neurotrophic factors as a therapy for diabetic neuropathy have been unsuccessful, newer agents and the possibilities uncovered by further studies should fuel clinical trials for several generations. It seems reasonable to anticipate that neurotrophic factor therapy, specifically targeted at different nerve fiber populations, might enter the therapeutic armamentarium. PMID:14668049

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

    PubMed Central

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

    1996-01-01

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

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

    PubMed

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

    2017-02-07

    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.

  10. 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

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

    PubMed

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

    2006-05-01

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

  12. Nerve growth factor promotes human hemopoietic colony growth and differentiation.

    PubMed Central

    Matsuda, H; Coughlin, M D; Bienenstock, J; Denburg, J A

    1988-01-01

    Nerve growth factor (NGF) is a neurotropic polypeptide necessary for the survival and growth of some central neurons, as well as sensory afferent and sympathetic neurons. Much is now known of the structural and functional characteristics of NGF, whose gene has recently been cloned. Since it is synthesized in largest amounts by the male mouse submandibular gland, its role exclusively in nerve growth is questionable. NGF also causes histamine release from rat peritoneal mast cells in vitro, and we have shown elsewhere that it causes significant, dose-dependent, generalized mast cell proliferation in the rat in vivo when administered neonatally. Our experiments now indicate that NGF causes a significant stimulation of granulocyte colonies grown from human peripheral blood in standard hemopoietic methylcellulose assays. Further, NGF appears to act in a relatively selective fashion to induce the differentiation of eosinophils and basophils/mast cells. Depletion experiments show that the NGF effect may be T-cell dependent and that NGF augments the colony-stimulating effect of supernatants from the leukemic T-cell (Mo) line. The hemopoietic activity of NGF is blocked by polyclonal and monoclonal antibodies to NGF. We conclude that NGF may indirectly act as a local growth factor in tissues other than those of the nervous system by causing T cells to synthesize or secrete molecules with colony-stimulating activity. In view of the synthesis of NGF in tissue injury, the involvement of basophils/mast cells and eosinophils in allergic and other inflammatory processes, and the association of mast cells with fibrosis and tissue repair, we postulate that NGF plays an important biological role in a variety of repair processes. PMID:3413109

  13. Epidermal growth factor receptor signaling in tissue

    SciTech Connect

    Shvartsman, Stanislav; Wiley, H. S.; Lauffenburger, Douglas A.

    2004-08-01

    Abstract: A peptide purified from the salivary gland of a mouse was shown few years ago to accelerate incisor eruption and eyelid opening in newborn mice, and was named epidermal growth factor (EGF). The members of this family of peptide growth factors had been identified in numerous physiological and pathological contexts. EGF binds to a cell surface EGF receptor, which induces a biochemical modification (phosphorylation) of the receptor's cytoplasmic tail. There is a growing consensus in the research community that, in addition to cellular and molecular studies, the dynamics of the EGFR network and its operation must be examined in tissues. A key challenge is to integrate the existing molecular and cellular information into a system-level description of the EGFR network at the tissue and organism level. In this paper, the two examples of EGFR signaling in tissues are described, and the recent efforts to model EGFR autocrine loops, which is a predominant mode of EGFR activation in vivo, are summarized.

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

    PubMed Central

    Bortvedt, Sarah F.; Lund, P. Kay

    2013-01-01

    Purpose of review To summarize recent evidence that IGF1 mediates growth effects of multiple trophic factors and discuss clinical relevance. Recent findings Recent reviews and original reports indicate benefits of growth hormone (GH) and long-acting glucagon-like peptide 2 (GLP2) analogues in short bowel syndrome and Crohn’s disease. This review highlights 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 SOCS 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. Summary 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. PMID:22241077

  15. Proteolytic Processing Regulates Placental Growth Factor Activities*

    PubMed Central

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

    2013-01-01

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

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

    PubMed

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

    1999-01-01

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

  17. Expression of transforming growth factor alpha, epidermal growth factor receptor and epidermal growth factor in precursor lesions to gastric carcinoma.

    PubMed Central

    Filipe, M. I.; Osborn, M.; Linehan, J.; Sanidas, E.; Brito, M. J.; Jankowski, J.

    1995-01-01

    Epidermal growth factor (EGF), its related peptide transforming growth factor (TGF-alpha) and their common receptor (EGFR) have been implicated in the control of cell proliferation and differentiation in the gastrointestinal epithelium and may play an important role in gastric carcinogenesis. We compared the immunohistochemical expression and topographic distribution of these peptides using Western blot analysis in gastric carcinoma precursor lesions and in non-cancer tissue. We observed: (i) increased and extended expression of TGF-alpha in normal mucosa and hyperplasia in carcinoma fields compared with non-cancer controls; (ii) increased expression of EGFR in intestinal metaplasia (IM) from carcinoma fields compared with controls; (iii) EGF expression was not detected in normal mucosa and only weakly in IM; (iv) coexpression of TGF-alpha/EGFR and EGF/EGFR was higher in intestinal metaplasia in carcinoma fields than in non-cancer controls. We conclude that altered expression of TGF-alpha/EGFR is associated with morphological changes during gastric carcinogenesis. In this regard increased expression of TGF-alpha is a very early event which is subsequently followed by up-regulation of EGFR and this has important biological and clinical implications. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:7819044

  18. Transforming growth factor beta in Alzheimer's disease.

    PubMed Central

    Chao, C C; Hu, S; Frey, W H; Ala, T A; Tourtellotte, W W; Peterson, P K

    1994-01-01

    Alzheimer's disease (AD) has been hypothesized to be an inflammatory condition. We hypothesized that anti-inflammatory cytokines, such as transforming growth factor beta (TGF-beta), counteract the inflammatory process. In the present study, we found that TGF-beta levels were elevated in both cerebrospinal fluid and serum samples obtained from AD patients < 6 h after death. Serum TGF-beta levels were also markedly elevated before death. These results suggest that elevated TGF-beta levels in AD may represent a protective host response to immunologically mediated neuronal injury. PMID:7496909

  19. Protein kinase C activators suppress stimulation of capillary endothelial cell growth by angiogenic endothelial mitogens

    PubMed Central

    1987-01-01

    The intracellular events regulating endothelial cell proliferation and organization into formalized capillaries are not known. We report that the protein kinase C activator beta-phorbol 12,13-dibutyrate (PDBu) suppresses bovine capillary endothelial (BCE) cell proliferation (K50 = 6 +/- 4 nM) and DNA synthesis in response to human hepatoma-derived growth factor, an angiogenic endothelial mitogen. In contrast, PDBu has no effect on the proliferation of bovine aortic endothelial cells and is mitogenic for bovine aortic smooth muscle and BALB/c 3T3 cells. Several observations indicate that the inhibition of human hepatoma- derived growth factor-stimulated BCE cell growth by PDBu is mediated through protein kinase C. Different phorbol compounds inhibit BCE cell growth according to their potencies as protein kinase C activators (12- O-tetradecanoylphorbol 13-acetate greater than PDBu much greater than beta-phorbol 12,13-diacetate much much greater than beta-phorbol; alpha- phorbol 12,13-dibutyrate; alpha-phorbol 12,13-didecanoate). PDBu binds to a single class of specific, saturable sites on the BCE cell with an apparent Kd of 8 nM, in agreement with reported affinities of PDBu for protein kinase C in other systems. Specific binding of PDBu to BCE cells is displaced by sn-1,2-dioctanoylglycerol, a protein kinase C activator and an analog of the putative second messenger activating this kinase in vivo. The weak protein kinase C activator, sn-1,2- dibutyrylglycerol, does not affect PDBu binding. A cytosolic extract from BCE cells contains a calcium/phosphatidylserine-dependent protein kinase that is activated by sn-1,2-dioctanoylglycerol and PDBu, but not by beta-phorbol. These findings indicate that protein kinase C activation can cause capillary endothelial cells to become desensitized to angiogenic endothelial mitogens. This intracellular regulatory mechanism might be invoked during certain phases of angiogenesis, for example when proliferating endothelial cells become

  20. Autologous Growth Factor Injections in Chronic Tendinopathy

    PubMed Central

    Sandrey, Michelle A.

    2014-01-01

    Reference: de Vos RJ, van Veldhoven PLJ, Moen MH, Weir A, Tol JL. Autologous growth factor injections in chronic tendinopathy: a systematic review. Br Med Bull. 2010;95:63–77. Clinical Question: The authors of this systematic review evaluated the literature to critically consider the effects of growth factors delivered through autologous whole-blood and platelet-rich–plasma (PRP) injections in managing wrist-flexor and -extensor tendinopathies, plantar fasciopathy, and patellar tendinopathy. The primary question was, according to the published literature, is there sufficient evidence to support the use of growth factors delivered through autologous whole-blood and PRP injections for chronic tendinopathy? Data Sources: The authors performed a comprehensive, systematic literature search in October 2009 using PubMed, MEDLINE, EMBASE, CINAHL, and the Cochrane library without time limits. The following key words were used in different combinations: tendinopathy, tendinosis, tendinitis, tendons, tennis elbow, plantar fasciitis, platelet rich plasma, platelet transfusion, and autologous blood or injection. The search was limited to human studies in English. All bibliographies from the initial literature search were also viewed to identify additional relevant studies. Study Selection: Studies were eligible based on the following criteria: (1) Articles were suitable (inclusion criteria) if the participants had been clinically diagnosed as having chronic tendinopathy; (2) the design had to be a prospective clinical study, randomized controlled trial, nonrandomized clinical trial, or prospective case series; (3) a well-described intervention in the form of a growth factor injection with either PRP or autologous whole blood was used; and (4) the outcome was reported in terms of pain or function (or both). Data Extraction: All titles and abstracts were assessed by 2 researchers, and all relevant articles were obtained. Two researchers independently read the full text of

  1. Autologous growth factor injections in chronic tendinopathy.

    PubMed

    Sandrey, Michelle A

    2014-01-01

    de Vos RJ, van Veldhoven PLJ, Moen MH, Weir A, Tol JL. Autologous growth factor injections in chronic tendinopathy: a systematic review. Br Med Bull. 2010;95:63-77. The authors of this systematic review evaluated the literature to critically consider the effects of growth factors delivered through autologous whole-blood and platelet-rich-plasma (PRP) injections in managing wrist-flexor and -extensor tendinopathies, plantar fasciopathy, and patellar tendinopathy. The primary question was, according to the published literature, is there sufficient evidence to support the use of growth factors delivered through autologous whole-blood and PRP injections for chronic tendinopathy? The authors performed a comprehensive, systematic literature search in October 2009 using PubMed, MEDLINE, EMBASE, CINAHL, and the Cochrane library without time limits. The following key words were used in different combinations: tendinopathy, tendinosis, tendinitis, tendons, tennis elbow, plantar fasciitis, platelet rich plasma, platelet transfusion, and autologous blood or injection. The search was limited to human studies in English. All bibliographies from the initial literature search were also viewed to identify additional relevant studies. Studies were eligible based on the following criteria: (1) Articles were suitable (inclusion criteria) if the participants had been clinically diagnosed as having chronic tendinopathy; (2) the design had to be a prospective clinical study, randomized controlled trial, nonrandomized clinical trial, or prospective case series; (3) a well-described intervention in the form of a growth factor injection with either PRP or autologous whole blood was used; and (4) the outcome was reported in terms of pain or function (or both). All titles and abstracts were assessed by 2 researchers, and all relevant articles were obtained. Two researchers independently read the full text of each article to determine if it met the inclusion criteria. If opinions differed on

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

    PubMed Central

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

    1989-01-01

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

  3. 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

  4. [Growth Hormone-Insulin Growth Factor I (GH-IGF-I) axis and growth].

    PubMed

    Castell, A-L; Sadoul, J-L; Bouvattier, C

    2013-10-01

    Normal human linear growth results from an evolutionary process expressing the sum effect of multiple genes. The growth hormone (GH) - insulin like growth factor (IGF)-I axis is one of the main actors in the growth process. Defects in this axis can be responsible for short or tall stature. Short stature is defined as smaller than - 2 standard deviations (SD). It is a very common reason for consultation in pediatrics; indeed, 2.5 % of children are concerned. Multiple causes make diagnosis difficult. In this article, we detail the most common constitutional causes of small size, including those related to a defect in the GH-IGF-I axis. Then, we report, the first results of the clinical and genetic study conducted on 213 patients with gigantism. Tall stature is defined by a height superior to 2 SD. Finally, recent work linking epigenetics and growth - via signaling pathways of GH-IGF-I axis - will be presented.

  5. Insulin-like growth factor and epidermal growth factor signaling in breast cancer cell growth: focus on endocrine resistant disease.

    PubMed

    Voudouri, Kallirroi; Berdiaki, Aikaterini; Tzardi, Maria; Tzanakakis, George N; Nikitovic, Dragana

    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.

  6. Growth factor control of epidermal growth factor receptor kinase activity via an intramolecular mechanism.

    PubMed

    Koland, J G; Cerione, R A

    1988-02-15

    The mechanism by which the protein kinase activity of the epidermal growth factor (EGF) receptor is activated by binding of growth factor was investigated. Detergent-solubilized receptor in monomeric form was isolated by sucrose density gradient centrifugation and both its kinase and autophosphorylation activities monitored. In a low ionic strength medium and with MnCl2 as an activator, the activity of the monomeric receptor was EGF-independent. However, with 0.25 M ammonium sulfate present, the MnCl2-stimulated kinase activity was strikingly EGF-dependent. In contrast, the kinase activity expressed in the presence of MgCl2 showed growth factor control in the absence of added salt. Under the conditions of these experiments there was apparently little tendency for growth factor to induce aggregation of the receptor, indicating that the allosteric activation of the receptor kinase by EGF occurred via an intramolecular mechanism. Whereas detergent-solubilized receptor was the subject of these studies, the kinase activity of cell surface receptors might also be controlled by an intramolecular mechanism. These results indicate that an individual receptor molecule has the potential to function as a transmembrane signal transducer.

  7. Nerve growth factor: neurotrophin or cytokine?

    PubMed

    Bonini, S; Rasi, G; Bracci-Laudiero, M L; Procoli, A; Aloe, L

    2003-06-01

    Nerve growth factor (NGF) is a neutrophin exerting an important role in the development and functions of the central and peripheral nervous system. However, it has recently been documented that several immune cells - such as mast cells, lymphocytes and eosinophils - produce, store and release NGF. Moreover, NGF high and low affinity receptors are widely expressed in the immune system, thus indicating the potential of responding to this neurotrophin through an autocrine mechanism. In fact, NGF influences development differentiation, chemotaxis and mediator release of inflammatory cells as well as fibroblast activation through a complex network influenced by other pro-inflammatory cytokines. Finally, NGF is increased in biological fluids of several allergic, immune and inflammatory diseases. Data reviewed suggest, therefore, that NGF might also be viewed as a (Th2?) cytokine with a modulatory role in allergic inflammation and tissue remodeling. Copyright 2003 S. Karger AG, Basel

  8. The Fibroblast Growth Factor signaling pathway

    PubMed Central

    Ornitz, David M; Itoh, Nobuyuki

    2015-01-01

    The signaling component of the mammalian Fibroblast Growth Factor (FGF) family is comprised of eighteen secreted proteins that interact with four signaling tyrosine kinase FGF receptors (FGFRs). Interaction of FGF ligands with their signaling receptors is regulated by protein or proteoglycan cofactors and by extracellular binding proteins. Activated FGFRs phosphorylate specific tyrosine residues that mediate interaction with cytosolic adaptor proteins and the RAS-MAPK, PI3K-AKT, PLCγ, and STAT intracellular signaling pathways. Four structurally related intracellular non-signaling FGFs interact with and regulate the family of voltage gated sodium channels. Members of the FGF family function in the earliest stages of embryonic development and during organogenesis to maintain progenitor cells and mediate their growth, differentiation, survival, and patterning. FGFs also have roles in adult tissues where they mediate metabolic functions, tissue repair, and regeneration, often by reactivating developmental signaling pathways. Consistent with the presence of FGFs in almost all tissues and organs, aberrant activity of the pathway is associated with developmental defects that disrupt organogenesis, impair the response to injury, and result in metabolic disorders, and cancer. © 2015 Wiley Periodicals, Inc. PMID:25772309

  9. Neuropeptides as lung cancer growth factors.

    PubMed

    Moody, Terry W; Moreno, Paola; Jensen, Robert T

    2015-10-01

    This manuscript is written in honor of the Festschrift for Abba Kastin. I met Abba at a Society for Neuroscience meeting and learned that he was Editor-in-Chief of the Journal Peptides. I submitted manuscripts to the journal on "Neuropeptides as Growth Factors in Cancer" and subsequently was named to the Editorial Advisory Board. Over the past 30 years I have published dozens of manuscripts in Peptides and reviewed hundreds of submitted manuscripts. It was always rewarding to interact with Abba, a consummate professional. When I attended meetings in New Orleans I would sometimes go out to dinner with him at the restaurant "Commanders Palace". When I chaired the Summer Neuropeptide Conference we were honored to have him receive the Fleur Strand Award one year in Israel. I think that his biggest editorial contribution has been the "Handbook of Biologically Active Peptides." I served as a Section Editor on "Cancer/Anticancer Peptides" and again found that it was a pleasure working with him. This review focuses on the mechanisms by which bombesin-like peptides, neurotensin and vasoactive intestinal peptide regulate the growth of lung cancer. Published by Elsevier Inc.

  10. Growth factors and cytokines in acute renal failure.

    PubMed

    Harris, R C

    1997-04-01

    The mammalian kidney is susceptible to injury by ischemia/reperfusion and toxins, and regeneration after injury is characterized by hyperplasia and recovery of the damaged epithelial cells that line the tubules. Locally produced growth factors may serve as mediators of nephrogenesis and differentiation during renal development and of renal regeneration after acute injury. In cultured cells, administration of one or a mixture of growth factors to quiescent cells will initiate progression through the cell cycle and cell division. In the adult kidney, cell division normally is very low, but will increase up to 10-fold after acute injury. In addition to proliferation after lethal injury, there also is cellular repair in cells that have undergone sublethal injury. Recent studies indicate that growth factors inhibit programmed cell death in response to acute injury. Growth factors also may initiate or promote protein and lipid biosynthesis and provide an intracellular milieu that promotes cellular repair. In addition to cellular repair, growth factors also may be involved in the re-establishment of cell-extracellular matrix and cell-cell integrity. Finally, growth factors may limit injury by decreasing the factors that induce damage. Increased local renal expression of growth factors in response to acute injury include heparin binding epidermal growth factor (HB-EGF), hepatocyte growth factor (HGF), insulin-like growth factor-I (IGF-I), transforming growth factor-beta, parathyroid hormone-related peptide, and acidic fibroblast growth factor. In a number of experimental models of acute renal injury, administration of exogenous growth factors has been shown to accelerate both structural and functional recovery. Specifically, EGF, IGF-1, and HGF all have been shown to be effective in this regard. These studies are reviewed and potential therapeutic uses of growth factors and cytokines will be discussed.

  11. [Regulation of uterine cellular proliferation with estrogens and growth factors].

    PubMed

    Alvarez-Rodríguez, C; Baiza-Guzmán, L A

    1996-09-01

    In this paper the role of estrogen and growth factors in the uterine cellular proliferation is analyzed. The evidences indicate that the estradiol-stimulate cell division is associated with the induction of expression of a variety of growth factors from the all major uterine cell types (epithelia, stroma and myometrium). These growth factors amplify the estrogen proliferation signal in autocrine and/or paracrin fashion. The best-studied growth factors in the uterine response to estradiol are epidermal growth factor (EGF) and insulin-like growth factor (IGF-1). Uterine cell proliferation is a complex process that involves interactions of several growth factors, ovarian steroids hormones action and cell to cell signaling.

  12. Hepatocyte growth factor, vascular endothelial growth factor, glial cell-derived neurotrophic factor and nerve growth factor are differentially affected by early chronic ethanol or red wine intake.

    PubMed

    Fiore, Marco; Mancinelli, Rosanna; Aloe, Luigi; Laviola, Giovanni; Sornelli, Federica; Vitali, Mario; Ceccanti, Mauro

    2009-08-10

    Ethanol intake during pregnancy and lactation induces severe changes in brain and liver throughout mechanisms involving growth factors. These are signaling molecules regulating survival, differentiation, maintenance and connectivity of brain and liver cells. Ethanol is an element of red wine which contains also compounds with antioxidant properties. Aim of the study was to investigate differences in hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), glial cell-derived neurotrophic factor (GDNF) and nerve growth factor (NGF) in brain areas and liver by ELISA of 1-month-old male mice exposed perinatally to ethanol at 11 vol.% or to red wine at same ethanol concentration. Ethanol was administered before and during pregnancy up to pups' weaning. Ethanol per se elevated HGF in liver and cortex, potentiated liver VEGF, reduced GDNF in the liver and decreased NGF content in hippocampus and cortex in the offspring. We did not find changes in HGF or NGF due to red wine exposure. However, we revealed elevation in VEGF levels in liver and reduced GDNF in the cortex of animals exposed to red wine but the VEGF liver increase was more marked in animals exposed to ethanol only compared to the red wine group. In conclusion the present findings in the mouse show differences in ethanol-induced toxicity when ethanol is administered alone or in red wine that may be related to compounds with antioxidant properties present in the red wine.

  13. Design of Growth Factor Sequestering Biomaterials

    PubMed Central

    Belair, David G.; Le, Ngoc Nhi; Murphy, William L.

    2014-01-01

    Growth factors (GFs) are major regulatory proteins that can govern cell fate, migration, and organization. Numerous aspects of the cell milieu can modulate cell responses to GFs, and GF regulation is often achieved by the native extracellular matrix (ECM). For example, the ECM can sequester GFs and thereby control GF bioavailability. In addition, GFs can exert distinct effects depending on whether they are sequestered in solution, at two-dimensional interfaces, or within three-dimensional matrices. Understanding how the context of GF sequestering impacts cell function in the native ECM can instruct the design of soluble or insoluble GF sequestering moieties, which can then be used in a variety of bioengineering applications. This Feature Article provides an overview of the natural mechanisms of GF sequestering in the cell milieu, and reviews the recent bioengineering approaches that have sequestered GFs to modulate cell function. Results to date demonstrate that the cell response to GF sequestering depends on the affinity of the sequestering interaction, the spatial proximity of sequestering in relation to cells, the source of the GF (supplemented or endogenous), and the phase of the sequestering moiety (soluble or insoluble). We highlight the importance of context for the future design of biomaterials that can leverage endogenous molecules in the cell milieu and mitigate the need for supplemented factors. PMID:25182455

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

    NASA Technical Reports Server (NTRS)

    Vandenburgh, Herman W.

    1987-01-01

    New muscle tissue culture techniques were developed to grow embryonic skeletal myofibers which are able to differentiate into more adultlike myofibers. Studies on mechanical simulation of cultured muscle cell growth will now be more directly applicable to mechanically-induced growth in adult muscle, and lead to better models for understanding muscle tissue atrophy caused by disuse in the microgravity of space.

  15. Growth factors and their relationship to neoplastic and paraneoplastic disease.

    PubMed

    Badawi, R A; Birns, J; Watson, T; Kalra, L

    2005-04-01

    Growth factors are extracellular signaling molecules that act in an autocrine and paracrine fashion to regulate growth, proliferation, differentiation, and survival of cells. Dysregulation of the growth factor networks is intimately related to the molecular pathogenesis of neoplastic and paraneoplastic disease. Increasing knowledge of the molecular mechanisms underlying growth factors and their actions on cell cycling, cell division, and cell death is shedding light on new therapeutic avenues for molecular targeting of tumors. Epidermal growth factor and vascular endothelial growth factor both offer examples of how growth factor biology and its relationship to cancer can be harnessed to create effective clinical therapeutic tools such as monoclonal antibodies. This approach heralds a future in which rational molecular oncological therapy may increasingly become the norm.

  16. Kinetics of epidermal growth factor in saliva.

    PubMed

    Ino, M; Ushiro, K; Ino, C; Yamashita, T; Kumazawa, T

    1993-01-01

    Human epidermal growth factor (hEGF) stimulates the growth and differentiation of various tissues. We measured EGF levels in saliva (n = 128), urine (n = 94), and serum (n = 99) with radioimmunoassay in order to study the kinetics of hEGF in saliva of normal subjects and patients with oral disease. Salivary EGF levels showed an apparent diurnal rhythm related to the taking of meals. Urinary and serum EGF levels showed no obvious diurnal rhythm. There was no significant correlation between salivary and urinary EGF levels, nor between salivary and serum EGF levels. Salivary EGF levels were significantly lower in the younger group (0-9 years old, 3.06 +/- 0.32 ng/ml, p < 0.05) than in the elder group (10-79 years old, 4.78 +/- 3.5 ng/ml), but did not correlate with age in the elder group. There was no significant difference between males and females between EGF levels in saliva, urine or serum. The relative proportion of EGF levels in submandibular gland saliva, parotid saliva, and whole saliva was 1:6:4. The positive rate of immunohistochemical EGF showed no significant differences between submandibular gland, parotid gland, sublingual gland or minor salivary gland. Salivary EGF levels were markedly low in patients with oral inflammations (stomatitis aphthosa, or peritonsillar abscess) or head and neck tumors (squamous cell carcinoma of the tongue, oral cavity, hypopharynx or larynx). These findings may be significant pathophysiologically. Low salivary EGF levels may reduce the capacity of oral mucosal defense mechanisms to fight against injury by physiochemical agents.

  17. 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…

  18. 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…

  19. Gene expression of growth factors and growth factor receptors for potential targeted therapy of canine hepatocellular carcinoma.

    PubMed

    Iida, Gentoku; Asano, Kazushi; Seki, Mamiko; Sakai, Manabu; Kutara, Kenji; Ishigaki, Kumiko; Kagawa, Yumiko; Yoshida, Orie; Teshima, Kenji; Edamura, Kazuya; Watari, Toshihiro

    2014-03-01

    The purpose of this study was to evaluate the gene expression of growth factors and growth factor receptors of primary hepatic masses, including hepatocellular carcinoma (HCC) and nodular hyperplasia (NH), in dogs. Quantitative real-time reverse transcriptase-polymerase chain reaction was performed to measure the expression of 18 genes in 18 HCCs, 10 NHs, 11 surrounding non-cancerous liver tissues and 4 healthy control liver tissues. Platelet-derived growth factor-B (PDGF-B), transforming growth factor-α, epidermal growth factor receptor, epidermal growth factor and hepatocyte growth factor were found to be differentially expressed in HCC compared with NH and the surrounding non-cancerous and healthy control liver tissues. PDGF-B is suggested to have the potential to become a valuable ancillary target for the treatment of canine HCC.

  20. HDGF-related protein-2 (HRP-2) acts as an oncogene to promote cell growth in hepatocellular carcinoma.

    PubMed

    Gao, Kun; Xu, Chen; Jin, Xiaofeng; Wumaier, Reziya; Ma, Jian; Peng, Jingtao; Wang, Yuqi; Tang, Yan; Yu, Long; Zhang, Pingzhao

    2015-03-20

    HDGFRP2 (HRP-2) belongs to the Hepatoma-derived growth factor (HDGF)-related proteins (HRPs) family, which are characterized by a conserved HATH/PWWP domain at a well-conserved region of the N-terminus. However, the cellular function of HRP-2 remains unknown. In this study, we showed for the first time that HRP-2 is frequently overexpressed in human HCC tissues at mRNA and protein levels. We further showed that HRP-2 can promote HCC cells growth in vitro and xenograft tumors in vivo. Using protein affinity purification methods, we searched for functional partners of HRP-2, and found that HRP-2 interacts with various proteins known to be involved in transcription elongation and processing. Furthermore, we demonstrate HRP-2 interacts and co-localizes with RNA processing regulator IWS1, and positively regulated the mRNA level of Cyclin D1. Together, our study suggests HRP-2 may act as an mRNA processing co-factor to promote cells growth by regulating the mRNA of key oncogenes, which can be explored further for cancer treatment.

  1. [Stem cells and growth factors in wound healing].

    PubMed

    Pikuła, Michał; Langa, Paulina; Kosikowska, Paulina; Trzonkowski, Piotr

    2015-01-02

    Wound healing is a complex process which depends on the presence of various types of cells, growth factors, cytokines and the elements of extracellular matrix. A wound is a portal of entry for numerous pathogens, therefore during the evolution wound healing process has formed very early, being critical for the survival of every individual. Stem cells, which give rise to their early descendants progenitor cells and subsequently differentiated cells, play a specific role in the process of wound healing. Among the most important cells which take part in wound healing the following cells need to be distinguished: epidermal stem cells, dermal precursor of fibroblasts, adipose-derived stem cells as well as bone marrow cells. The activity of these cells is strictly regulated by various growth factors, inter alia epidermal growth factor (EGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), transforming growth factor (TGF), vascular endothelial growth factor (VEGF). Any disorders in functioning of stem cells and biological activity of growth factors may lead to the defects in wound healing, for instance delayed wound healing or creation of hypertrophic scars. Therefore, knowledge concerning the mechanisms of wound healing is extremely essential from clinical point of view. In this review the current state of the knowledge of the role of stem cells and growth factors in the process of wound healing has been presented. Moreover, some clinical aspects of wound healing as well as the possibility of the therapy based on stem cells and growth factors have included.

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

    PubMed Central

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

    1989-01-01

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

  3. Direct binding of hepatocyte growth factor and vascular endothelial growth factor to CD44v6.

    PubMed

    Volz, Yvonne; Koschut, David; Matzke-Ogi, Alexandra; Dietz, Marina S; Karathanasis, Christos; Richert, Ludovic; Wagner, Moritz G; Mély, Yves; Heilemann, Mike; Niemann, Hartmut H; Orian-Rousseau, Véronique

    2015-06-29

    CD44v6, a member of the CD44 family of transmembrane glycoproteins is a co-receptor for two receptor tyrosine kinases (RTKs), Met and VEGFR-2 (vascular endothelial growth factor receptor 2). CD44v6 is not only required for the activation of these RTKs but also for signalling. In order to understand the role of CD44v6 in Met and VEGFR-2 activation and signalling we tested whether CD44v6 binds to their ligands, HGF (hepatocyte growth factor) and VEGF (vascular endothelial growth factor), respectively. FACS analysis and cellular ELISA showed binding of HGF and VEGF only to cells expressing CD44v6. Direct binding of CD44v6 to HGF and VEGF was demonstrated in pull-down assays and the binding affinities were determined using MicroScale Thermophoresis, fluorescence correlation spectroscopy and fluorescence anisotropy. The binding affinity of CD44v6 to HGF is in the micromolar range in contrast with the high-affinity binding measured in the case of VEGF and CD44v6, which is in the nanomolar range. These data reveal a heparan sulfate-independent direct binding of CD44v6 to the ligands of Met and VEGFR-2 and suggest different roles of CD44v6 for these RTKs.

  4. [Growth factors in human tooth development].

    PubMed

    Bellone, C; Barni, T; Pagni, L; Balboni, G C; Vannelli, G B

    1990-03-01

    Our research concerns the immunohistochemical localization of EGF and IGF-I receptors in the tooth germ, using monoclonal antibodies. The results show that in the early phases of human tooth development EGF and IGF-I receptors are present. At bud stage both receptors are localized at dental laminae level, in some epithelial cells of the tooth bud and in some mesenchymal cells. At cap stage the receptors are present in the outer and inner enamel epithelium, and in some cells of stellate reticulum. As far as concerns the mesenchymal cells, some cells of dental papilla in contact with enamel organ, are intensely positive. The immunopositivity is present also in some mesenchymal cells at follicular level. At late cap stage and at early bell stage receptors are not present at inner enamel epithelium level but they can be detectable in the mesenchyma of dental papilla and in some cells of the follicle. On the basis of these results it may be hypothesized that EGF and IGF-I can act as growth factors in the modulation of cellular proliferation and differentiation during the human tooth morphogenesis. Moreover, it is possible that these substances can play a role in the mesenchymal-epithelial interaction in the developing human tooth.

  5. Transforming growth factor beta1 and aldosterone

    PubMed Central

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

    2016-01-01

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

  6. Vascular Endothelial Growth Factor in Eye Disease

    PubMed Central

    Penn, J.S.; Madan, A.; Caldwell, R.B.; Bartoli, M.; Caldwell, R.W.; Hartnett, M.E.

    2012-01-01

    Collectively, angiogenic ocular conditions represent the leading cause of irreversible vision loss in developed countries. In the U.S., for example, retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration are the principal causes of blindness in the infant, working age and elderly populations, respectively. Evidence suggests that vascular endothelial growth factor (VEGF), a 40 kDa dimeric glycoprotein, promotes angiogenesis in each of these conditions, making it a highly significant therapeutic target. However, VEGF is pleiotropic, affecting a broad spectrum of endothelial, neuronal and glial behaviors, and confounding the validity of anti-VEGF strategies, particularly under chronic disease conditions. In fact, among other functions VEGF can influence cell proliferation, cell migration, proteolysis, cell survival and vessel permeability in a wide variety of biological contexts. This article will describe the roles played by VEGF in the pathogenesis of retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration. The potential disadvantages of inhibiting VEGF will be discussed, as will the rationales for targeting other VEGF-related modulators of angiogenesis. PMID:18653375

  7. Nerve growth factor actions on the brain

    SciTech Connect

    Martinez, H.J.

    1989-01-01

    We examined the effect of the trophic protein, nerve growth factor (NGF), on cultures of fetal rat neostriatum and basal forebrain-medial septal area (BF-MS) to define its role in brain development. Treatment of cultures with NGF resulted in an increase in the specific activity of the cholinergic enzyme choline acetyltransferase (CAT) in both brain areas. CAT was immunocytochemically localized to neurons. In the BF-MS, NGF treatment elicited a marked increase in staining intensity and an apparent increase in the number of CAT-positive neurons. Moreover, treatment of BF-MS cultures with NGF increased the activity of acetylcholinesterase, suggesting that the cholinergic neuron as a whole was affected. To begin defining mechanisms of action of NGF in the BF-MS, we detected NGF receptors by two independent methods. Receptors were localized to two different cellular populations: neuron-like cells, and non-neuron-like cells. Dissociation studies with ({sup 125}I)NGF suggested that high affinity receptors were localized to the neuron-like population. Only low-affinity receptors were localized to the non-neuron-like cells. Moreover, employing combined immunocytochemistry and ({sup 125}I)NGF autoradiography, we detected a subpopulation of CAT-containing neutrons that exhibited high-affinity binding. Unexpectedly, a gamma-aminobutyric acid (GABA)-containing cell group also expressed high affinity binding. However, only subsets of cholinergic or GABA neurons expressed high-affinity biding, suggesting that these transmitter populations are composed of differentially response subpopulations.

  8. Nerve growth factor enhances sleep in rabbits.

    PubMed

    Takahashi, S; Krueger, J M

    1999-04-02

    Nerve growth factor (NGF) elicits rapid-eye-movement sleep (REMS) in cats. Removal of NGF receptor-positive cholinergic basal forebrain neurons inhibits REMS in rats. The aim of the present study was to determine the effects of NGF on sleep and brain temperature (Tbr) in rabbits. Male rabbits were implanted with electroencephalograph (EEG) electrodes, a brain thermistor and an intraventricular (i.c.v.) guide cannula. Rabbits received human beta-NGF i.c.v. (0.01, 0.1, 1.0 or 10 microg] and on a separate day, 25 microl pyrogen-free saline i.c.v. as control. EEG and Tbr were recorded for 23 h after injections. The highest two doses of NGF increased both non-REMS and REMS across the 23-h recording period. REMS was enhanced dose-dependently. Tbr was not affected by any dose of NGF. These results suggest that NGF is involved in both REMS and non-REMS regulation.

  9. [Epidermal growth factor, innovation and safety].

    PubMed

    Esquirol Caussa, Jordi; Herrero Vila, Elisabeth

    2015-10-05

    Bioidentical recombinant human epidermal growth factor (rhEGF) is available in concentrations and purity suitable for therapeutic use in long time stable formulations. Beneficial effects in several skin pathologies and lesions have been reported (traumatic and surgical wound healing, laser induced wounds, abnormal scars, keloids, radiation or chemotherapy induced dermatitis, post inflammatory hyperpigmentation or for skin aging damage repairing) and also may be considered for the treatment of several oropharingeal and high gastroesophageal tract mucosa diseases (mouth sores, pharyngeal fistulas, ulcers), and several corneal or conjunctive mucosa lesions. rhEGF has not shown any important side or collateral effects in humans or in laboratory experimentation animals, showing optimal tolerability and safety with continuous use for months. Compounding gives advantages of versatility, individualization, personalization, molecular stability, safety and effectiveness in ideal conditions, showing good tissue penetration, both on intact skin and skin lesions that expose the lower planes to the surface. rhEGF compounds can be considered for prevention or as a treatment of diverse skin and mucosa diseases and conditions through compounding preparations.

  10. [Periodontal regeneration: the use of polypeptide growth factors].

    PubMed

    Di Genio, M; Barone, A; Ramaglia, L; Sbordone, L

    1994-10-01

    Polypeptide growth factors are a class of potent natural biologic mediators which regulate many of the activities of wound healing including cell proliferation, migration and metabolism. Periodontal regeneration is thought to require the migration and proliferation of periodontal ligament cells on the root surface. In fact, repopulation of the detached root surface by cells from periodontal ligament (PDL) is a prerequisite for new attachment formation. Many studies suggested that Polypeptide Growth Factors (PGF) such as Insulin-like Growth Factor I (IGF-I), Platelet Derived Growth Factor (PDGF), Transforming Growth Factor B (TGF-B), Epidermal Growth Factor (EGF), are important mediators of cellular events in wound healing. Studies in vitro analysed the mitogenic effects determined on periodontal ligament cells by growth factors using (3H) Thymidine incorporation during DNA synthesis. The results suggested that recombinant human PDGF and IGF-I stimulate the proliferation of PDL fibroblastic cells and the combination of these growth factors showed a synergistic effect revealing the highest mitogenic effect among all individual growth factors as well as any combination of the growth factors tested. Furthermore these studies demonstrated that rh-PDGF and IGF-I stimulate chemotaxis of PDL fibroblastic cells, and supported a role for TGF-B as a regulator of the mitogenic response to PDGF in these cells. Other studies in vivo showed periodontal tissues regeneration introducing mixtures of recombinant human platelet derived growth factor and insulin-like growth factor into lesions of experimentally induced periodontitis in beagle dogs and monkeys.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Nerve growth factor gene therapy in Alzheimer disease.

    PubMed

    Tuszynski, Mark H

    2007-01-01

    Nervous system growth factors potently stimulate cell function and prevent neuronal death. These broad effects on survival and function arise from direct downstream activation of antiapoptotic pathways, inhibition of proapoptotic pathways, and stimulation of functionally important cellular mechanisms including ERK/MAP kinase and CREB. Thus, as a class, growth factors offer the potential to treat neurodegenerative disorders for the first time by preventing neuronal degeneration rather than compensating for cell loss after it has occurred. Different growth factors affect distinct and specific populations of neurons: the first nervous system growth factor identified, nerve growth factor, potentially stimulates the survival and function of basal forebrain cholinergic neurons, suggesting that nerve growth factor could be a means for reducing the cholinergic component of cell degeneration in Alzheimer disease. This review will discuss the transition of growth factors from preclinical studies to human clinical trials in Alzheimer disease. The implementation of clinical testing of growth factor therapy for neurologic disease has been constrained by the dual need to achieve adequate concentrations of these proteins in specific brain regions containing degenerating neurons, and preventing growth factor spread to nontargeted regions to avoid adverse effects. Gene therapy is one of a limited number of potential methods for achieving these requirements.

  12. Novel Drosophila receptor that binds multiple growth factors

    SciTech Connect

    Rosner, M.R.; Thompson, K.L.; Garcia, V.; Decker, S.J.

    1986-05-01

    The authors have recently reported the identification of a novel growth factor receptor from Drosophila cell cultures that has dual binding specificity for both insulin and epidermal growth factor (EGF). This 100 kDa protein is also antigenically related to the cytoplasmic region of the mammalian EGF receptor-tyrosine kinase. They now report that this protein binds to mammalian nerve growth factor and human transforming growth factor alpha as well as insulin and EGF with apparent dissociation constants ranging from 10/sup -6/ to 10/sup -8/ M. The 100 kDa protein can be affinity-labeled with these /sup 125/I-labeled growth factors after immunoprecipitation with anti-EGF receptor antiserum. These four growth factors appear to share a common binding site, as evidenced by their ability to block affinity labelling by /sup 125/I-insulin. No significant binding to the 100 kDa protein was observed with platelet-derived growth factor, transforming growth factor beta, or glucagon. The 100 kDa Drosophila protein has a unique ligand-binding spectrum with no direct counterpart in mammalian cells and may represent an evolutionary precursor of the mammalian receptors for these growth factors.

  13. Role of tissue growth factors in aqueous humor homeostasis.

    PubMed

    Welge-Lüssen, U; May, C A; Neubauer, A S; Priglinger, S

    2001-04-01

    The aqueous humor supplies nutrients to the nonvascularized cornea, lens, and trabecular meshwork. A number of tissue growth factors have been detected in this fluid. The composition of these proteins changes dramatically with different ocular conditions, such as inflammation and glaucoma. In this review, an overview of new findings regarding effects of aqueous humor growth factors is given. Our main emphasis is on the regulation of the avascular anterior eye compartment, the possible role of growth factors in the pathogenesis of glaucoma, and the importance of growth factors for the special immunosuppressive status of the anterior chamber.

  14. Insulin-Like Growth Factor-Independent Effects of Growth Hormone on Growth Plate Chondrogenesis and Longitudinal Bone Growth.

    PubMed

    Wu, Shufang; Yang, Wei; De Luca, Francesco

    2015-07-01

    GH stimulates growth plate chondrogenesis and longitudinal bone growth directly at the growth plate. However, it is not clear yet whether these effects are entirely mediated by the local expression and action of IGF-1 and IGF-2. To determine whether GH has any IGF-independent growth-promoting effects, we generated (TamCart)Igf1r(flox/flox) mice. The systemic injection of tamoxifen in these mice postnatally resulted in the excision of the IGF-1 receptor (Igf1r) gene exclusively in the growth plate. (TamCart)Igf1r(flox/flox) tamoxifen-treated mice [knockout (KO) mice] and their Igf1r(flox/flox) control littermates (C mice) were injected for 4 weeks with GH. At the end of the 4-week period, the tibial growth and growth plate height of GH-treated KO mice were greater than those of untreated C or untreated KO mice. The systemic injection of GH increased the phosphorylation of Janus kinase 2 and signal transducer and activator of transcription 5B in the tibial growth plate of the C and KO mice. In addition, GH increased the mRNA expression of bone morphogenetic protein-2 and the mRNA expression and protein phosphorylation of nuclear factor-κB p65 in both C and KO mice. In cultured chondrocytes transfected with Igf1r small interfering RNA, the addition of GH in the culture medium significantly induced thymidine incorporation and collagen X mRNA expression. In conclusion, our findings demonstrate that GH can promote growth plate chondrogenesis and longitudinal bone growth directly at the growth plate, even when the local effects of IGF-1 and IGF-2 are prevented. Further studies are warranted to elucidate the intracellular molecular mechanisms mediating the IGF-independent, growth-promoting GH effects.

  15. Transforming growth factor-β and Smads.

    PubMed

    Lan, Hui Yao; Chung, Arthur C K

    2011-01-01

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

  16. Fibroblast Growth Factor Signaling in Metabolic Regulation

    PubMed Central

    Nies, Vera J. M.; Sancar, Gencer; Liu, Weilin; van Zutphen, Tim; Struik, Dicky; Yu, Ruth T.; Atkins, Annette R.; Evans, Ronald M.; Jonker, Johan W.; Downes, Michael Robert

    2016-01-01

    The prevalence of obesity is a growing health problem. Obesity is strongly associated with several comorbidities, such as non-alcoholic fatty liver disease, certain cancers, insulin resistance, and type 2 diabetes, which all reduce life expectancy and life quality. Several drugs have been put forward in order to treat these diseases, but many of them have detrimental side effects. The unexpected role of the family of fibroblast growth factors in the regulation of energy metabolism provides new approaches to the treatment of metabolic diseases and offers a valuable tool to gain more insight into metabolic regulation. The known beneficial effects of FGF19 and FGF21 on metabolism, together with recently discovered similar effects of FGF1 suggest that FGFs and their derivatives carry great potential as novel therapeutics to treat metabolic conditions. To facilitate the development of new therapies with improved targeting and minimal side effects, a better understanding of the molecular mechanism of action of FGFs is needed. In this review, we will discuss what is currently known about the physiological roles of FGF signaling in tissues important for metabolic homeostasis. In addition, we will discuss current concepts regarding their pharmacological properties and effector tissues in the context of metabolic disease. Also, the recent progress in the development of FGF variants will be reviewed. Our goal is to provide a comprehensive overview of the current concepts and consensuses regarding FGF signaling in metabolic health and disease and to provide starting points for the development of FGF-based therapies against metabolic conditions. PMID:26834701

  17. In vivo growth of a bioengineered internal anal sphincter: comparison of growth factors for optimization of growth and survival.

    PubMed

    Miyasaka, Eiichi A; Raghavan, Shreya; Gilmont, Robert R; Mittal, Krittika; Somara, Sita; Bitar, Khalil N; Teitelbaum, Daniel H

    2011-02-01

    Our laboratory has developed and implanted a novel bioengineered internal anal sphincter (IAS) to treat anal incontinence. Fibroblast growth factor-2 (FGF-2) has been used in mice; however, the optimal growth factor for successful IAS implantation is unclear. This study compares several growth factors in order to optimize IAS viability and functionality. Bioengineered IAS rings were implanted subcutaneously into the dorsum of wildtype C57Bl/6 mice, with an osmotic pump dispensing FGF-2, vascular endothelial growth factor (VEGF), or platelet-derived growth factor (PDGF) (n = 4 per group). Control mice received IAS implants but no growth factor. The IAS was harvested approximately 25 days post-implantation. Tissue was subjected to physiologic testing, then histologically analyzed. Muscle phenotype was confirmed by immunofluorescence. All implants supplemented with growth factors maintained smooth muscle phenotype. Histological scores, blood vessel density and muscle fiber thickness were all markedly better with growth factors. Neovascularization was comparable between the three growth factors. Basal tonic force of the constructs was highest with VEGF or PDGF. All growth factors demonstrated excellent performance. As our ultimate goal is clinical implantation, our strong results with PDGF, a drug approved for use in the United States and the European Union, pave the way for translating bioengineered IAS implantation to the clinical realm.

  18. Expression of growth factors and growth factor receptors in human cleft-affected tissue.

    PubMed

    Krivicka, Benita; Pilmane, Mara; Akota, Ilze

    2013-01-01

    OBJECTIVE. To investigate cleft disordered tissue in children with cleft palate and cleft lip with or without alveolar clefting for detection of local tissue growth factors and growth factor receptors and compare findings. Design. Morphological analysis of human tissue. Patients. Three groups were studied: 14 patients with cleft palate at the age from eight months to 18 years and two months, 12 patients with cleft lip with or without alveolar clefting in the age from four months to 15 years and four months and 11 control patients. RESULTS. In general, cleft palate disordered tissue showed more prominent expression of BMP2/4 (z=3.574; p=0.0004) and TGFβ (z=2.127; p=0.033), while expression of TGFBR3 significantly higher was only in connective tissue (z=3.822; p=0.0001). Cleft lip affected tissue showed significantly pronounced expression of FGFR1 in general as well as separately in epithelium. CONCLUSIONS. The marked and statistically significant expression of BMP 2/4 in cleft palate disordered soft tissue probably is delayed, but still proliferation and differentiation as well as tissue, especially, bone remodeling contributing signal. Cleft palate affected tissue show more prominent expression of TGFβ, still the weak regional expression of TGFβ type III receptors prove the disordered tissue growth and changed TGFβ signalling pathway in postnatal pathogenesis. In general, expression of TGFβ, BMP 2/4 and FGFR1 is significantly different, giving evidence to the involvement of these mentioned factors in the cleft severity morphopathogenesis.

  19. 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

  20. An Exploratory Study of Factors Differentiating Freshmen Educational Growth.

    ERIC Educational Resources Information Center

    Lenning, Oscar T.

    The present study was an exploratory investigation of factors that differentiate students who exhibit "negative educational growth" from a group of equally able students who exhibit marked "positive educational growth." Educational growth was operationally defined as estimated true test-retest change on American College Tests (ACT) composite…

  1. 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.

  2. 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.

  3. Expression of vascular endothelial growth factor and basic fibroblast growth factor in extramammary Paget disease.

    PubMed

    Xu, Xiaoyun; Shao, Ning; Qiao, Di; Wang, Zengjun; Song, Ningjing; Song, Ninghong

    2015-01-01

    Extramammary Paget's disease (EMPD) is a special type of cancers. The etiology of the disease is still unclear. We aimed to study the expression differences of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in EMPD tissues and corresponding adjacent normal tissues. The mRNA expression was detected by RT-PCR and the protein expression was explored by immunohistochemistry. Higher immunostaining signal scores of bFGF and VEGF in EMPD tissues had been found (z=-3.827, P<0.001, z=-3.729, P<0.001, respectively). In addition, the mRNA expression of bFGF and VEGF was higher in EMPD tissues, which had been validated by RT-PCR (t=5.771, P<0.001, t=3.304, P=0.004, respectively). The VEGF and bFGF might be the key signaling proteins in angiogenesis of EMPD. How to block the VEGF and bFGF in EMPD and to destroy the blood supply of the tumor cells becomes the focus of our future research.

  4. Nerve growth factor-mediated vascular endothelial growth factor expression of astrocyte in retinal vascular development.

    PubMed

    Kim, You Sun; Jo, Dong Hyun; Lee, Hanjae; Kim, Jin Hyoung; Kim, Kyu-Won; Kim, Jeong Hun

    2013-02-22

    The angiogenic aspect of neurotrophins and their receptors rather than the neuroscientific aspect has been focused. However, their role in retinal vascular development is underdiscovered. The purpose of this study is to understand the role of neurotrophin receptors in retinal vascular development and the mechanisms of their action. To identify the expression of tropomyosin receptor kinase receptor (Trk) in developing retina, tissues of 4, 8, 12, 16 and 26 day-old mice were prepared for experiments. Immunohistochemistry and immunofluorescence double staining against glial fibrillary acidic protein and type IV collagen were performed. TrkA was expressed mainly along the vessel structure in inner part of retina, especially in retinal astrocyte. In cultured primary astrocyte, recombinant nerve growth factor (NGF) was used to activate TrkA. NGF induced the phosphorylation of TrkA, and it also enhanced the level of activated Akt and vascular endothelial growth factor (VEGF) mRNA. Inhibition of phosphoinositide 3-kinase (PI3K) reversed the NGF-induced activation of these two molecules. This study demonstrated that TrkA activation on NGF leads to VEGF elevation by PI3K-Akt pathway and therefore suggested that TrkA could be a stimulator of retinal vascular development. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Epidermal growth factor receptor mutation enhances expression of vascular endothelial growth factor in lung cancer.

    PubMed

    Hung, Ming-Szu; Chen, I-Chuan; Lin, Paul-Yann; Lung, Jr-Hau; Li, Ya-Chin; Lin, Yu-Ching; Yang, Cheng-Ta; Tsai, Ying-Huang

    2016-12-01

    Epidermal growth factor receptor (EGFR) activation has been demonstrated to have a critical role in tumor angiogenesis. In the present study, the correlation between EGFR mutations and vascular endothelial growth factor (VEGF) was investigated in lung cancer cell lines and non-small-cell lung cancer (NSCLC) tumor tissues. VEGF levels were significantly increased in culture medium of lung cancer cells and NSCLC tissues with EGFR mutations (H1650 vs. A549, P=0.0399; H1975 vs. A549, P<0.0001). Stable lung cancer cell lines expressing mutant (exon 19 deletion, E746-A750; exon 21 missense mutation, L858R) and wild-type EGFR genes were established. Significantly increased expression of VEGF and stronger inhibitory effects of gefitinib to VEGF expression were observed in exon 19 deletion stable lung cancer cells (exon 19 deletion vs. wild-type EGFR, P=0.0005). The results of the present study may provide an insight into the association of mutant EGFR and VEGF expression in lung cancer, and may assist with further development of targeted therapy for NSCLC in the future.

  6. Material factors influencing metallic whisker growth

    NASA Astrophysics Data System (ADS)

    Rodekohr, Chad L.

    Whiskering refers to the formation of slender, long, metallic filaments, much thinner than a human hair, that grow on a metallic thin film surface. They are readily observed for pure and alloyed zinc (Zn), silver (Ag), cadmium (Cd), indium (In), and tin (Sn) surfaces. The longest reported whisker length is 4.5 mm long but most high-aspect ratio whiskers range from 1-500 mum. The focus of this research is upon Sn whiskers. Sn whiskers pose serious reliability problems for the electronics industry and are known to be the source of failure in a wide range of electronic devices, such as nuclear power facilities, heart pacemakers, commercial satellites, aviation radar, telecommunication equipment, and desktop computers. The problem with whiskering has been recently exacerbated by the worldwide shift to lead (Pb) free electronics and the continuing reduction in electrical contact pitches. A thorough understanding of the growth mechanism of Sn whiskers is urgently needed. Currently, there is no universally accepted model that explains the broad range of observations on whiskering. The goals of this research are: (1) to develop a more detailed understanding of the physical mechanisms leading to the initiation and growth of Sn whiskers and (2) to outline reasonable mitigation strategies that could be followed to reduce or eliminate the problem of Sn whiskers. The major contributions of this work are: (1) A reliable method for growing Sn whiskers with predictable incubation times has been developed and tested. (2) A surface oxide is not necessary for whisker growth. (3) Intermetallic compounds (IMC) are not necessary for whisker growth. (4) Smoother, not rougher, substrate surfaces promote whisker growth. (5) Whiskers grow under both compressive and tensile thin film stress states. (6) Whisker growth increases with externally applied compression and tension forces. (7) Sn whiskers are composed of pure Sn except for the expected thin, native Sn oxide on their surface. (8) For

  7. Nerve growth factor and epidermal growth factor stimulate clusterin gene expression in PC12 cells.

    PubMed Central

    Gutacker, C; Klock, G; Diel, P; Koch-Brandt, C

    1999-01-01

    Clusterin (apolipoprotein J) is an extracellular glycoprotein that might exert functions in development, cell death and lipid transport. Clusterin gene expression is elevated at sites of tissue remodelling, such as differentiation and apoptosis; however, the signals responsible for this regulation have not been identified. We use here the clusterin gene as a model system to examine expression in PC12 cells under the control of differentiation and proliferation signals produced by nerve growth factor (NGF) and by epidermal growth factor (EGF) respectively. NGF induced clusterin mRNA, which preceded neurite outgrowth typical of neuronal differentiation. EGF also activated the clusterin mRNA, demonstrating that both proliferation and differentiation signals regulate the gene. To localize NGF- and EGF-responsive elements we isolated the clusterin promoter and tested it in PC12 cell transfections. A 2.5 kb promoter fragment and two 1.5 and 0.3 kb deletion mutants were inducible by NGF and EGF. The contribution to this response of a conserved activator protein 1 (AP-1) motif located in the 0.3 kb fragment was analysed by mutagenesis. The mutant promoter was not inducible by NGF or EGF, which identifies the AP-1 motif as an element responding to both factors. Binding studies with PC12 nuclear extracts showed that AP-1 binds to this sequence in the clusterin promoter. These findings suggest that NGF and EGF, which give differential gene regulation in PC12 cells, resulting in neuronal differentiation and proliferation respectively, use the common Ras/extracellular signal-regulated kinase/AP-1 signalling pathway to activate clusterin expression. PMID:10215617

  8. Heparin-binding epidermal growth factor-like growth factor and hepatocyte growth factor inhibit cholestatic liver injury in mice through different mechanisms

    PubMed Central

    Sakamoto, Kouichi; Khai, Ngin Cin; Wang, Yuqing; Irie, Rie; Takamatsu, Hideo; Matsufuji, Hiroshi; Kosai, Ken-Ichiro

    2016-01-01

    In contrast to hepatocyte growth factor (HGF), the therapeutic potential and pathophysiologic roles of heparin-binding epidermal growth factor-like growth factor (HB-EGF) in liver diseases remain relatively unknown. To address the lack of effective pharmacologic treatments for cholestatic liver injuries, as well as to clarify the biologic features of these growth factors, we explored the effects of HB-EGF and HGF in mice with cholestatic liver injury induced by bile duct ligation (BDL). The mice were assessed 3, 5 and/or 14 days after BDL (acute, subacute and/or chronic phases, respectively) and intravenous injection of adenoviral vector expressing LacZ (control), HB-EGF, HGF, or HB-EGF and HGF. HB-EGF, HGF, or a combination of the growth factors exerted potent antioncotic (antinecrotic), antiapoptotic, anticholestatic, and regenerative effects on hepatocytes in vivo, whereas no robust antiapoptotic or regenerative effects were detected in interlobular bile ducts. Based on serum transaminase levels, the acute protective effects of HB-EGF on hepatocytes were greater than those of HGF. On the other hand, liver fibrosis and cholestasis during the chronic phase were more potently inhibited by HGF compared with HB-EGF. Compared with either growth factor alone, combining HB-EGF and HGF produced greater anticholestatic and regenerative effects during the chronic phase. Taken together, these findings suggest that HB-EGF and HGF inhibited BDL-induced cholestatic liver injury, predominantly by exerting acute cytoprotective and chronic antifibrotic effects, respectively; combining the growth factors enhanced the anticholestatic effects and liver regeneration during the chronic phase. Our results contribute to a better understanding of the pathophysiologic roles of HB-EGF and HGF, as well as to the development of novel effective therapies for cholestatic liver injuries. PMID:27779646

  9. 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 ...

  10. The discovery of basic fibroblast growth factor/fibroblast growth factor-2 and its role in haematological malignancies.

    PubMed

    Ribatti, Domenico; Vacca, Angelo; Rusnati, Marco; Presta, Marco

    2007-01-01

    Basic fibroblast growth factor/fibroblast growth factor-2 is one of the best characterized of the pro-angiogenic cytokines. This review describes its history, as well as its role in tumor angiogenesis associated with haematological malignancies, as traced by the main contributions to the international medical literature.

  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. 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

  13. Regulation of transferrin receptor expression at the cell surface by insulin-like growth factors, epidermal growth factor and platelet-derived growth factor

    SciTech Connect

    Davis, R.J.; Kuck, L.; Faucher, M.; Czech, M.P.

    1986-05-01

    Addition of platelet-derived growth factor (PDGF), recombinant insulin-like growth factor I (rIGF-I) or epidermal growth factor (EGF) to BALB/c 3T3 fibroblasts causes a marked increase in the binding of (/sup 125/I) diferric transferrin to cell surface receptors. This effect is very rapid and is complete within 5 minutes. The effect is transient with (/sup 125/I) diferric transferrin binding returning to control values within 25 minutes. In contrast, PDGF and rIGF-I cause a prolonged stimulation of (/sup 125/I) diferric transferrin binding that could be observed up to 2 hours. The increase in the binding of (/sup 125/I) diferric transferrin caused by growth factors was investigated by analysis of the binding isotherm. EGF, PDGF and rIGF-I were found to increase the cell surface expression of transferrin receptors rather than to alter the affinity of the transferrin receptors. Furthermore, PDGF and rIGF-I stimulated the sustained uptake of (/sup 59/Fe) diferric transferrin by BALB/c 3T3 fibroblasts. Thus, the effect of these growth factors to increase the cell surface expression of the transferrin receptor appears to have an important physiological consequence.

  14. High-growth-factor implosions (HEP4)

    SciTech Connect

    Landen, O.L.; Keane, C.J.; Hammel, B.A.

    1996-06-01

    In inertial confinement fusion (ICF), the kinetic energy of an ablating, inward-driven, solid spherical shell is used to compressionally heat the low-density fuel inside. For a given drive, the maximum achievable compressed fuel density and temperature - and hence the maximum neutron production rate depend on the degree of shell isentropy and integrity maintained during the compression. Shell integrity will be degraded by hydrodynamic instability growth of areal density imperfections in the capsule. Surface imperfections on the shell grow as a result of the Richtmyer-Meshkov and Rayleigh-Taylor (RT) instabilities when the shell is accelerated by the ablating lower-density plasma. Perturbations at the outer capsule surface are transferred hydrodynamically to the inner surface, where deceleration of the shell by the lower-density fuel gives rise to further RT growth at the pusher-fuel interface.

  15. Efficacy of glial growth factor and nerve growth factor on the recovery of traumatic facial paralysis.

    PubMed

    Yildiz, Mucahit; Karlidag, Turgut; Yalcin, Sinasi; Ozogul, Candan; Keles, Erol; Alpay, Hayrettin Cengiz; Yanilmaz, Muhammed

    2011-08-01

    The aim of this study was to assess the effects of Glial growth factor (GGF) and nerve growth factor (NGF) on nerve regeneration in facial nerve anastomosis. In this study, approximately a 1-mm segment was resected from the facial nerve and the free ends were anastomosed. All animals underwent the same surgical procedure and 30 rabbits were grouped randomly in three groups. Control group, the group without any medications; NGF group, the group receiving 250 ng/0.1 ml NGF in the epineurium at the site of anastomosis; GBF group, the group receiving 500 ng/0.1 ml GGF in the epineurium at the site of anastomosis. Medications were given at the time of surgery, and at 24 and 48 h postoperatively. After 2 months, the sites of anastomosis were excised and examined using the electron microscope. It was found that the best regeneration was in the group receiving GGF as compared to the control group in terms of nerve regeneration. Schwann cell and glial cell proliferation were found to be significantly higher in the group receiving GGF as compared to the group receiving NGF. Besides, the number of myelin debris, an indicator of degeneration, was significantly lower in the group with GGF as compared to NGF and control groups (p < 0.005). Using GGF and NGF in order to increase regeneration after nerve anastomosis in experimental traumatic facial nerve paralysis may be a hopeful alternative treatment option in the future. However, further studies on human studies are required to support these results.

  16. Maternal growth factor regulation of human placental development and fetal growth.

    PubMed

    Forbes, Karen; Westwood, Melissa

    2010-10-01

    Normal development and function of the placenta is critical to achieving a successful pregnancy, as normal fetal growth depends directly on the transfer of nutrients from mother to fetus via this organ. Recently, it has become apparent from both animal and human studies that growth factors within the maternal circulation, for example the IGFs, are important regulators of placental development and function. Although these factors act via distinct receptors to exert their effects, the downstream molecules activated upon ligand/receptor interaction are common to many growth factors. The expression of numerous signaling molecules is altered in the placentas from pregnancies affected by the fetal growth complications, fetal growth restriction, and macrosomia. Thus, targeting these molecules may lead to more effective treatments for complications of pregnancy associated with altered placental development. Here, we review the maternal growth factors required for placental development and discuss their mechanism of action.

  17. Guanine is a growth factor for Legionella species.

    PubMed Central

    Pine, L; Franzus, M J; Malcolm, G B

    1986-01-01

    Evaluation of previously described chemically defined media for the growth of Legionella pneumophila showed that these media supported poor growth of several strains of L. pneumophila and did not support growth of certain of the Legionella species described later. Growth was stimulated by the dialysate from yeast extract but not by the nondialyzable fraction. Further investigations indicated that the active factors from the yeast extract dialysate were purine or pyrimidine derivatives, and certain known purines and pyrimidines were found to stimulate growth. Of these, guanine universally stimulated growth of all Legionella strains and was a growth requirement for several of the species tested. A balanced, N-(2-acetamido)-2-aminoethanesulfonic acid-buffered, chemically defined medium having guanine or a purine-pyrimidine mix is presented for the general growth of Legionella species. PMID:3700600

  18. Platelet-rich growth factor in oral and maxillofacial surgery

    PubMed Central

    Pal, Uma Shanker; Mohammad, Shadab; Singh, Rakesh K.; Das, Somdipto; Singh, Nimisha; Singh, Mayank

    2012-01-01

    Platelet-rich growth factor is an innovative regenerative therapy used to promote hard and soft tissue healing. It involves the application of autologous platelet-leukocyte-rich plasma containing growth factors and thrombin directly to the site of treatment. It is the intrinsic growth factors released by activated platelets which are concentrated in a topical gel formula. Clinically, it is an affordable treatment with potentially broad spectrum of applications in maxillofacial surgery especially in the treatment of complex or refractory wounds. The present article reviews its various applications not only in the specialization of oral and maxillofacial surgery but also in regenerative medicine. PMID:23833484

  19. 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.

  20. 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.

  1. Body size regulation and insulin-like growth factor signaling.

    PubMed

    Hyun, Seogang

    2013-07-01

    How animals achieve their specific body size is a fundamental, but still largely unresolved, biological question. Over the past decades, studies on the insect model system have provided some important insights into the process of body size determination and highlighted the importance of insulin/insulin-like growth factor signaling. Fat body, the Drosophila counterpart of liver and adipose tissue, senses nutrient availability and controls larval growth rate by modulating peripheral insulin signaling. Similarly, insulin-like growth factor I produced from liver and muscle promotes postnatal body growth in mammals. Organismal growth is tightly coupled with the process of sexual maturation wherein the sex steroid hormone attenuates body growth. This review summarizes some important findings from Drosophila and mammalian studies that shed light on the general mechanism of animal size determination.

  2. Dual control of cell growth by somatomedins and platelet-derived growth factor.

    PubMed Central

    Stiles, C D; Capone, G T; Scher, C D; Antoniades, H N; Van Wyk, J J; Pledger, W J

    1979-01-01

    Quiescent BALB/c 3T3 cells exposed briefly to a platelet-derived growth factor (PDGF) become "competent" to replicate their DNA but do not "progress" into S phase unless incubated with growth factors contained in platelet-poor plasma. Plasma from hypophysectomized rats is deficient in progression activity; it does not stimulate PDGF-treated competent cells to synthesize DNA, demonstrating that somatomedin C is required for progression. Various growth factors were tested for progression activity and competence activity by using BALB/c 3T3 tissue culture assays. Multiplication stimulating activity and other members of the somatomedin family of growth factors are (like somatomedin C) potent mediators of progression. Other mitogenic agents, such as fibroblast growth factor, are (like PDGF) potent inducers of competence. Growth factors with potent progression activity have little or no competence activity and vice versa. In contrast, simian virus 40 provides both competence and progression activity. Coordinate control of BALB/c 3T3 cell growth in vitro by competence factors and somatomedins may be a specific example of a common pattern of growth regulation in animal tissues. PMID:312500

  3. Insulin-like growth factor-I gene expression in three models of accelerated lung growth.

    PubMed

    Nobuhara, K K; DiFiore, J W; Ibla, J C; Siddiqui, A M; Ferretti, M L; Fauza, D O; Schnitzer, J J; Wilson, J M

    1998-07-01

    We have learned previously that in utero tracheal ligation reverses the structural and physiological effects of surgically created congenital diaphragmatic hernia. In addition, we have discovered that postnatal lung growth similarly can be accelerated using liquid-based airway distension with perfluorocarbon. Another model of accelerated lung growth is that of compensatory growth seen after neonatal pneumonectomy. In all of these models, growth has occurred because of an increase in alveolar number rather than enlargement of preexisting alveoli. However, the molecular mechanisms underlying these processes remain unknown. The purpose of this study was to determine if gene expression could be altered by changes in physical forces in the prenatal and postnatal lung. The three models of accelerated lung growth studied were the following: (1) The prenatal group, consisted of fetal lambs (n = 12) that underwent the surgical creation of a left diaphragmatic hernia at 90 days' gestation. Six of these animals also underwent simultaneous tracheal ligation. (2) The PFC group consisted of five neonatal animals that underwent isolation of the superior segment of the right upper lobe, with intrabronchial distension with perfluorocarbon to 7 to 10 mm Hg pressure for a 3-week period. (3) The postpneumonectomy group consisted of four neonatal animals that underwent left pneumonectomy. In the fetal study, lungs were retrieved at term (130 days), and in the postnatal study, lungs were retrieved 3 weeks after initial intervention. In all cases, RNA was extracted from snap-frozen lung samples and Northern blot analysis performed. Insulinlike growth factor-I, insulinlike growth factor-II, and vascular endothelial growth factor gene expression were analyzed by densitometry. Insulinlike growth factor-I gene expression was found to be decreased in association with experimental diaphragmatic hernia (P = .005), but restored to normal with tracheal ligation. Insulinlike growth factor-I gene

  4. 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.

  5. Cardiac Regeneration using Growth Factors: Advances and Challenges

    PubMed Central

    Rebouças, Juliana de Souza; Santos-Magalhães, Nereide Stela; Formiga, Fabio Rocha

    2016-01-01

    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. PMID:27355588

  6. Polyamines: essential factors for growth and survival.

    PubMed

    Kusano, T; Berberich, T; Tateda, C; Takahashi, Y

    2008-08-01

    Polyamines are low molecular weight, aliphatic polycations found in the cells of all living organisms. Due to their positive charges, polyamines bind to macromolecules such as DNA, RNA, and proteins. They are involved in diverse processes, including regulation of gene expression, translation, cell proliferation, modulation of cell signalling, and membrane stabilization. They also modulate the activities of certain sets of ion channels. Because of these multifaceted functions, the homeostasis of polyamines is crucial and is ensured through regulation of biosynthesis, catabolism, and transport. Through isolation of the genes involved in plant polyamine biosynthesis and loss-of-function experiments on the corresponding genes, their essentiality for growth is reconfirmed. Polyamines are also involved in stress responses and diseases in plants, indicating their importance for plant survival. This review summarizes the recent advances in polyamine research in the field of plant science compared with the knowledge obtained in microorganisms and animal systems.

  7. Actions of activin A, connective tissue growth factor, hepatocyte growth factor and teratocarcinoma-derived growth factor 1 on the development of the bovine preimplantation embryo.

    PubMed

    Kannampuzha-Francis, Jasmine; Tribulo, Paula; Hansen, Peter J

    2016-05-17

    The reproductive tract secretes bioactive molecules collectively known as embryokines that can regulate embryonic growth and development. In the present study we tested four growth factors expressed in the endometrium for their ability to modify the development of the bovine embryo to the blastocyst stage and alter the expression of genes found to be upregulated (bone morphogenetic protein 15 (BMP15) and keratin 8, type II (KRT8)) or downregulated (NADH dehydrogenase 1 (ND1) and S100 calcium binding protein A10 (S100A10)) in embryos competent to develop to term. Zygotes were treated at Day 5 with 0.01, 0.1 or 1.0 nM growth factor. The highest concentration of activin A increased the percentage of putative zygotes that developed to the blastocyst stage. Connective tissue growth factor (CTGF) increased the number of cells in the inner cell mass (ICM), decreased the trophectoderm : ICM ratio and increased blastocyst expression of KRT8 and ND1. The lowest concentration of hepatocyte growth factor (HGF) reduced the percentage of putative zygotes becoming blastocysts. Teratocarcinoma-derived growth factor 1 increased total cell number at 0.01 nM and expression of S100A10 at 1.0 nM, but otherwise had no effects. Results confirm the prodevelopmental actions of activin A and indicate that CTGF may also function as an embryokine by regulating the number of ICM cells in the blastocyst and altering gene expression. Low concentrations of HGF were inhibitory to development.

  8. Effect of sericin on diabetic hippocampal growth hormone/insulin-like growth factor 1 axis

    PubMed Central

    Chen, Zhihong; Yang, Songhe; He, Yaqiang; Song, Chengjun; Liu, Yongping

    2013-01-01

    Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats. PMID:25206472

  9. A growth factor phenotype map for ovine preimplantation development.

    PubMed

    Watson, A J; Watson, P H; Arcellana-Panlilio, M; Warnes, D; Walker, S K; Schultz, G A; Armstrong, D T; Seamark, R F

    1994-04-01

    The reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the patterns of expression for several growth factor ligand and receptor genes during ovine preimplantation development. Transcripts for insulin-like growth factor (IGF)-I, IGF-II, and the receptors for insulin and IGF-I were detected throughout ovine preimplantation development from the 1-cell to the blastocyst stage. Transforming growth factor alpha (TGF alpha) transcripts were also detected throughout ovine preimplantation development. The mRNAs encoding basic fibroblast growth factor (bFGF) were detected in all stages of the ovine preimplantation embryo, although the relative abundance of this transcript consistently decreased from the 1-cell to the blastocyst stage, suggesting that it may represent a maternal transcript in early sheep embryos. Transcripts encoding ovine trophoblast protein (oTP) were detected only within blastocyst-stage embryos. Primary ovine oviduct cell cultures express the transcripts for IGF-II, IGF-I, TGF alpha, bFGF, TGF beta 1, and the receptors for insulin and IGF-I, suggesting that paracrine growth factor circuits may exist between the oviduct epithelium and the early ovine embryo. Transcripts for insulin, epidermal growth factor (EGF), and nerve growth factor (NGF) were not detected in any stage of the ovine preimplantation embryo or within the oviduct cell preparations. The expression of growth factor transcripts very early in mammalian development would predict that these molecules fulfil a necessary role(s) in supporting the progression of early embryos through the preimplantation interval. Our future efforts will be directed to understanding the nature of these putative regulatory pathways.

  10. Lifetime growth in wild meerkats: incorporating life history and environmental factors into a standard growth model.

    PubMed

    English, Sinéad; Bateman, Andrew W; Clutton-Brock, Tim H

    2012-05-01

    Lifetime records of changes in individual size or mass in wild animals are scarce and, as such, few studies have attempted to model variation in these traits across the lifespan or to assess the factors that affect them. However, quantifying lifetime growth is essential for understanding trade-offs between growth and other life history parameters, such as reproductive performance or survival. Here, we used model selection based on information theory to measure changes in body mass over the lifespan of wild meerkats, and compared the relative fits of several standard growth models (monomolecular, von Bertalanffy, Gompertz, logistic and Richards). We found that meerkats exhibit monomolecular growth, with the best model incorporating separate growth rates before and after nutritional independence, as well as effects of season and total rainfall in the previous nine months. Our study demonstrates how simple growth curves may be improved by considering life history and environmental factors, which may be particularly relevant when quantifying growth patterns in wild populations.

  11. The neglected role of insulin-like growth factors in the maternal circulation regulating fetal growth.

    PubMed

    Sferruzzi-Perri, A N; Owens, J A; Pringle, K G; Roberts, C T

    2011-01-01

    Maternal insulin-like growth factors (IGFs) play a pivotal role in modulating fetal growth via their actions on both the mother and the placenta. Circulating IGFs influence maternal tissue growth and metabolism, thereby regulating nutrient availability for the growth of the conceptus. Maternal IGFs also regulate placental morphogenesis, substrate transport and hormone secretion, all of which influence fetal growth either via indirect effects on maternal substrate availability, or through direct effects on the placenta and its capacity to supply nutrients to the fetus. The extent to which IGFs influence the mother and/or placenta are dependent on the species and maternal factors, including age and nutrition. As altered fetal growth is associated with increased perinatal morbidity and mortality and a greater risk of developing degenerative diseases in adult life, understanding the role of maternal IGFs during pregnancy is essential in order to identify mechanisms underlying altered fetal growth and offspring programming.

  12. The neglected role of insulin-like growth factors in the maternal circulation regulating fetal growth

    PubMed Central

    Sferruzzi-Perri, A N; Owens, J A; Pringle, K G; Roberts, C T

    2011-01-01

    Maternal insulin-like growth factors (IGFs) play a pivotal role in modulating fetal growth via their actions on both the mother and the placenta. Circulating IGFs influence maternal tissue growth and metabolism, thereby regulating nutrient availability for the growth of the conceptus. Maternal IGFs also regulate placental morphogenesis, substrate transport and hormone secretion, all of which influence fetal growth either via indirect effects on maternal substrate availability, or through direct effects on the placenta and its capacity to supply nutrients to the fetus. The extent to which IGFs influence the mother and/or placenta are dependent on the species and maternal factors, including age and nutrition. As altered fetal growth is associated with increased perinatal morbidity and mortality and a greater risk of developing degenerative diseases in adult life, understanding the role of maternal IGFs during pregnancy is essential in order to identify mechanisms underlying altered fetal growth and offspring programming. PMID:20921199

  13. Therapeutic angiogenesis using novel vascular endothelial growth factor-E/human placental growth factor chimera genes.

    PubMed

    Inoue, Natsuo; Kondo, Takahisa; Kobayashi, Koichi; Aoki, Mika; Numaguchi, Yasushi; Shibuya, Masabumi; Murohara, Toyoaki

    2007-01-01

    Vascular endothelial growth factor-A (VEGF-A) promotes angiogenesis but causes adverse side effects such as edema or tissue inflammation. VEGF-E, found in the genome of the Orf virus, specifically binds to VEGF receptor-2 and shows mitotic activity on endothelial cells. Recently, we created two forms of VEGF-E and human placental growth factor (PlGF) chimera genes (VEGF-E chimera #9 and VEGF-E chimera #33), which are humanized genes with VEGF-E function but showing less antigenicity. We examined potential proangiogenic activities of these chimera genes. Four types of expression plasmids (pCDNA3.1-LacZ, phVEGF-A, pVEGF-Echimera#9, and pVEGF-Echimera#33) were administered in a rat model of hindlimb ischemia. Either pVEGF-Echimera#9, pVEGF-Echimera#33, or phVEGF-A significantly increased the ratio of ischemic/normal hindlimb blood-flow compared with the control pCDNA3.1-LacZ treated group (by 1.5-fold, 1.5-fold, and 1.4-fold, respectively, P<0.05). Histochemical staining by alkaline phosphatase also revealed that either pVEGF-Echimera#9, pVEGF-Echimera#33, or phVEGF-A increased the capillary density compared with the pCDNA3.1-LacZ treated group (1.4-fold, 1.5-fold, and 1.5-fold, respectively, P<0.05). Furthermore, immunostaining for anti-ED1 revealed that fewer macrophages had infiltrated in both pVEGF-Echimera#9 and pVEGF-Echimera#33 groups compared with the phVEGF-A group (P<0.05). Novel VEGF-E/human PlGF chimera genes, pVEGF-Echimera#9, and pVEGF-Echimera#33 significantly stimulated angiogenesis in response to tissue ischemia to an almost identical extent to that induced by phVEGF-A with fewer tissue inflammation responses.

  14. Intrauterine growth correlation to postnatal growth--influence of risk factors and complications in pregnancy.

    PubMed

    Larsen, T; Greisen, G; Petersen, S

    1997-01-20

    In a population of 616 pregnant women with increased risk of intrauterine growth retardation, we examined the relationship of third trimester fetal growth to maternal and pregnancy risk factors, the infants condition at birth, and postnatal growth. Intrauterine growth velocity was calculated from repeated estimations of fetal weight using ultrasound. Postnatal growth up to 3 months was measured in 313 of the infants. Intrauterine growth velocity was directly correlated to birth weight deviation (R = 0.35, P < 0.0001) and inversely correlated to postnatal growth (R = 0.21, P = 0.0001). Heavy smoking throughout pregnancy was the most pronounced factor associated with loss of fetal growth percentiles (P = 0.006), and it was also associated with postnatal catchup (P = 0.01). Infants who needed neonatal care had significantly lower intrauterine growth velocities compared to the rest of the study group; no correlation was found between intrauterine growth velocity and Apgar scores or umbilical pH. It is concluded that growth retardation in the third trimester can be identified by ultrasound fetometry, and is associated with maladaptation at birth and postnatal catchup. However, the correlations were weak suggesting that deviation at birth reflects, only to a limited degree, acceleration or deceleration of growth in the third trimester.

  15. Heparin-binding epidermal growth factor-like growth factor regulates fibroblast growth factor-2 expression in aortic smooth muscle cells.

    PubMed

    Peifley, K A; Alberts, G F; Hsu, D K; Feng, S L; Winkles, J A

    1996-08-01

    Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a vascular smooth muscle cell (SMC) mitogen and chemotactic factor that is expressed by endothelial cells, SMCs, monocytes/macrophages, and T lymphocytes. Both the membrane-anchored HB-EGF precursor and the secreted mature HB-EGF protein are biologically active; thus, HB-EGF may stimulate SMC growth via autocrine, paracrine, and juxtacrine mechanisms. In the present study, we report that HB-EGF treatment of serum-starved at aortic SMCs can induce fibroblast growth factor (FGF)-2 (basic FGF) gene expression but not FGF-1 (acidic FGF) gene expression. Increased FGF-2 mRNA expression is first detectable at 1 hour after HB-EGF addition, and maximal FGF-2 mRNA levels, corresponding to an approximately 46-fold level of induction, are present at 4 hours. The effect of HB-EGF on FGF-2 mRNA levels appears to be mediated primarily by a transcriptional mechanism and requires de novo synthesized proteins. HB-EGF induction of FGF-2 mRNA levels can be inhibited by treating cells with the anti-inflammatory glucocorticoid dexamethasone or the glycosaminoglycan heparin. Finally, Western blot analyses indicate that HB-EGF-treated SMCs also produce an increased amount of FGF-2 protein. These results indicate that HB-EGF expressed at sites of vascular injury or inflammation in vivo may upregulate FGF-2 production by SMCs.

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

    PubMed

    Li, Qinglei

    2014-01-01

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

  17. [The changes of the attributable factors of child growth].

    PubMed

    Chen, Chun-ming; He, Wu; Chang, Su-ying

    2006-11-01

    To rule out the attributable factors of child growth in China and the changes of the factors in the past 15 years for the planning of future nutrition improvement of children in China. The datasets of 1990 - 2005 China Food and Nutrition Surveillance were used and the Multi-factorial Logistic Regression analysis was used. The AR% of these factors and the changes of the attributable factors during the past 15 years were presented. The main factors attributed to the growth of children under 5 in year 2005 were low education level of mothers (AR = 40.5%), floating out-for-job mothers (AR% = 35.5%), No egg introduction in the past 24 hours (AR = 24.2%), No milk introduction in the past 24 hours(18.7%) and household income below national poverty line (21.9%). Many of the attributable factors have improved significantly during the past 15 years. However, the increasing number of floating out-for-job mothers will have more impact on the quality of child feeding and child care. Social economic development is the direct factors to child growth, while other factors such as feeding and mother care are critical factors could either accelerate or counteract the positive effects of the favorable socioeconomic development. To improve height growth is essential to further enhance health and fitness of children under 5 focused nutrition and dietary intervention should be implemented.

  18. Neutrophil biology and the next generation of myeloid growth factors.

    PubMed

    Dale, David C

    2009-01-01

    Neutrophils are the body's critical phagocytic cells for defense against bacterial and fungal infections; bone marrow must produce approximately 10 x 10(9) neutrophils/kg/d to maintain normal blood neutrophil counts. Production of neutrophils depends on myeloid growth factors, particularly granulocyte colony-stimulating factor (G-CSF). After the original phase of development, researchers modified these growth factors to increase their size and delay renal clearance, increase their biologic potency, and create unique molecules for business purposes. Pegylated G-CSF is a successful product of these efforts. Researchers have also tried to identify small molecules to serve as oral agents that mimic the parent molecules, but these programs have been less successful. In 2006, the European Medicines Agency established guidelines for the introduction of new biologic medicinal products claimed to be similar to reference products that had previously been granted marketing authorization in the European community, called bio-similars. Globally, new and copied versions of G-CSF and other myeloid growth factors are now appearing. Some properties of the myeloid growth factors are similar to other agents, offering opportunities for the development of alternative drugs and treatments. For example, recent research shows that hematopoietic progenitor cells can be mobilized with a chemokine receptor antagonist, chemotherapy, G-CSF, and granulocyte macrophage colony-stimulating factor. Advances in neutrophil biology coupled with better understanding and development of myeloid growth factors offer great promise for improving the care of patients with cancer and many other disorders.

  19. [Novel role of growth factors in ovary function].

    PubMed

    Amsterdam, Abraham

    2010-12-01

    The development of the DNA microarray technique facilitated systematic studies of the modulation of gene function. Considerable attention has been focused on members of the growth factor family to elucidate the main regulators of oocyte maturation and ovarian follicle rupture. Among these growth factors, it was found, both in rodents and in humans, that amphiregulin (Ar) and epiregulin (Ep) of the epidermal growth factor (EGF) family were dramatically up-regulated by gonadotrophins in the intact ovary and in primary granulosa cells, respectively. Their role in cumulus expansion and oocyte maturation was established in rodents, and their synthesis under LH stimulation in granulosa cells was demonstrated in humans. To be activated, Ar and Ep must be cleaved by a disintegrin and metalloproteinases (ADAMs) family. However, the precise processing of Ar and Ep by the cumulus cells is still obscure. Future investigations using DNA microarray technique may reveal the repertoire of genes activated in Ar- and Ep-stimulated cumulus cells and may help elucidate the molecular basis of ovulation. EFG-like factors are also involved in triggering ovarian cancer The author hypothesized that the normal ovary maintains cyclicity in the formation of these growth factors preventing the ovary from developing ovarian cancer In ovarian cancer these growth factors are continuously formed in an autocrine manner, leading to transformation and subsequently to ovarian cancer. These growth factors are essential for both normal and neoplastic transformation of the ovary. Taking into consideration these growth factors in the treatment of ovarian malfunction may be one way of curing ovarian cancer.

  20. [Enhancement of epidermal regeneration by recombinant vaccinia virus growth factor].

    PubMed

    Petrov, V S; Cheshenko, I O; Omigov, V V; Azaev, M Sh; Krendel'shchikov, A V; Ovechkina, L G; Cheshenko, N V; Malygin, E G

    1998-01-01

    Examining the specific activity has showed that recombinant vaccinia virus growth factor binds to appropriate receptors on the A-431 cell surface and prompts the healing acceleration of degree III burns in rats. This recombinant factor did not demonstrate pyrogenicity or toxicogenicity in tests on rabbits, guinea-pits, noninbred albino mice.

  1. 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

  2. In situ formation of poly(vinyl alcohol)–heparin hydrogels for mild encapsulation and prolonged release of basic fibroblast growth factor and vascular endothelial growth factor

    PubMed Central

    Roberts, Justine J; Farrugia, Brooke L; Green, Rylie A; Rnjak-Kovacina, Jelena; Martens, Penny J

    2016-01-01

    Heparin-based hydrogels are attractive for controlled growth factor delivery, due to the native ability of heparin to bind and stabilize growth factors. Basic fibroblast growth factor and vascular endothelial growth factor are heparin-binding growth factors that synergistically enhance angiogenesis. Mild, in situ encapsulation of both basic fibroblast growth factor and vascular endothelial growth factor and subsequent bioactive dual release has not been demonstrated from heparin-crosslinked hydrogels, and the combined long-term delivery of both growth factors from biomaterials is still a major challenge. Both basic fibroblast growth factor and vascular endothelial growth factor were encapsulated in poly(vinyl alcohol)-heparin hydrogels and demonstrated controlled release. A model cell line, BaF32, was used to show bioactivity of heparin and basic fibroblast growth factor released from the gels over multiple days. Released basic fibroblast growth factor promoted higher human umbilical vein endothelial cell outgrowth over 24 h and proliferation for 3 days than the poly(vinyl alcohol)-heparin hydrogels alone. The release of vascular endothelial growth factor from poly(vinyl alcohol)-heparin hydrogels promoted human umbilical vein endothelial cell outgrowth but not significant proliferation. Dual-growth factor release of basic fibroblast growth factor and vascular endothelial growth factor from poly(vinyl alcohol)-heparin hydrogels resulted in a synergistic effect with significantly higher human umbilical vein endothelial cell outgrowth compared to basic fibroblast growth factor or vascular endothelial growth factor alone. Poly(vinyl alcohol)-heparin hydrogels allowed bioactive growth factor encapsulation and provided controlled release of multiple growth factors which is beneficial toward tissue regeneration applications. PMID:27895888

  3. In situ formation of poly(vinyl alcohol)-heparin hydrogels for mild encapsulation and prolonged release of basic fibroblast growth factor and vascular endothelial growth factor.

    PubMed

    Roberts, Justine J; Farrugia, Brooke L; Green, Rylie A; Rnjak-Kovacina, Jelena; Martens, Penny J

    2016-01-01

    Heparin-based hydrogels are attractive for controlled growth factor delivery, due to the native ability of heparin to bind and stabilize growth factors. Basic fibroblast growth factor and vascular endothelial growth factor are heparin-binding growth factors that synergistically enhance angiogenesis. Mild, in situ encapsulation of both basic fibroblast growth factor and vascular endothelial growth factor and subsequent bioactive dual release has not been demonstrated from heparin-crosslinked hydrogels, and the combined long-term delivery of both growth factors from biomaterials is still a major challenge. Both basic fibroblast growth factor and vascular endothelial growth factor were encapsulated in poly(vinyl alcohol)-heparin hydrogels and demonstrated controlled release. A model cell line, BaF32, was used to show bioactivity of heparin and basic fibroblast growth factor released from the gels over multiple days. Released basic fibroblast growth factor promoted higher human umbilical vein endothelial cell outgrowth over 24 h and proliferation for 3 days than the poly(vinyl alcohol)-heparin hydrogels alone. The release of vascular endothelial growth factor from poly(vinyl alcohol)-heparin hydrogels promoted human umbilical vein endothelial cell outgrowth but not significant proliferation. Dual-growth factor release of basic fibroblast growth factor and vascular endothelial growth factor from poly(vinyl alcohol)-heparin hydrogels resulted in a synergistic effect with significantly higher human umbilical vein endothelial cell outgrowth compared to basic fibroblast growth factor or vascular endothelial growth factor alone. Poly(vinyl alcohol)-heparin hydrogels allowed bioactive growth factor encapsulation and provided controlled release of multiple growth factors which is beneficial toward tissue regeneration applications.

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

    PubMed

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

    2014-11-01

    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.

  5. 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

  6. Transforming growth factor alpha controls the transition from hypertrophic cartilage to bone during endochondral bone growth.

    PubMed

    Usmani, Shirine E; Pest, Michael A; Kim, Gunwoo; Ohora, Sara N; Qin, Ling; Beier, Frank

    2012-07-01

    We have recently identified transforming growth factor alpha (TGFα) as a novel growth factor involved in the joint disease osteoarthritis. The role of TGFα in normal cartilage and bone physiology however, has not been well defined. The objective of this study was to determine the role of TGFα in bone development through investigation of the Tgfa knockout mouse. The gross skeletons as well as the cartilage growth plates of Tgfa knockout mice and their control littermates were examined during several developmental stages ranging from newborn to ten weeks old. Knockout mice experienced skeletal growth retardation and expansion of the hypertrophic zone of the growth plate. These phenotypes were transient and spontaneously resolved by ten weeks of age. Tgfa knockout growth plates also had fewer osteoclasts along the cartilage/bone interface. Furthermore, knockout mice expressed less RUNX2, RANKL, and MMP13 mRNA in their cartilage growth plates than controls did. Tgfa knockout mice experience a delay in bone development, specifically the conversion of hypertrophic cartilage to true bone. The persistence of the hypertrophic zone of the growth plate appears to be mediated by a decrease in MMP13 and RANKL expression in hypertrophic chondrocytes and a resulting reduction in osteoclast recruitment. Overall, TGFα appears to be an important growth factor regulating the conversion of cartilage to bone during the process of endochondral ossification. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. [Role of maternal risk factors in foetal growth impairment].

    PubMed

    Cieślik, Krystyna; Waszak, Małgorzata

    2007-01-01

    Clinical goal of foetal growth evaluation is primarily to identify foetuses with an accelerated or decelerated growth rate. Chief criterion of normal intrauterine development is a timely delivery of a neonate meeting applicable health norms. Obstetrician's decisions on how a pregnancy should be handled are based on foetal development and growth forecast and take into account whether foetal growth is normal, accelerated or decelerated. Such assessment requires correct determination of foetal age, selection of the most appropriate growth rate standards and defining potential risk factors. The aim of this study was to evaluate the impact of pre-selected risk factors on foetal growth. Material was 3889 foetuses (2203 males and 1686 females) stillborn between 20th and 42nd week of pregnancy. Morphological development of the study material was characterised based upon the values of seven pre-defined somatic features and the weight of eight internal organs. Clinical classification of maternal risk factors revealed four factors of most potent impact on foetal development, ie. maternal age, number of pregnancy and artificial and natural miscarriage history. Verification of developmental status of foetuses, ie. exposed vs. non-exposed to risk factors, allowed to determine the potency of selected risk factors. The non-exposed group was characterised by normal growth rate during each of stage of development meaning that despite being stillborn these foetuses did not differ significantly in their development of the selected features from live born foetuses. In the exposed group, however, the rate of development, compared to the standard, was significantly reduced and starting from the 35th week it was below the 5th percentile. It can, therefore, be seen that the exposed group development was significantly influenced by an adverse impact of risk factors. Our results show that the risk factors for the exposed group are a group of maternal risk factors impairing foetal growth and

  8. Insulin-like growth factors act synergistically with basic fibroblast growth factor and nerve growth factor to promote chromaffin cell proliferation.

    PubMed Central

    Frödin, M; Gammeltoft, S

    1994-01-01

    We have investigated the effects of insulin-like growth factors (IGFs), basic fibroblast growth factor (bFGF), and nerve growth factor (NGF) on DNA synthesis in cultured chromaffin cells from fetal, neonatal, and adult rats by using 5-bromo-2'-deoxyuridine (BrdUrd) pulse labeling for 24 or 48 h and immunocytochemical staining of cell nuclei. After 6 days in culture in the absence of growth factors, nuclear BrdUrd incorporation was detected in 30% of fetal chromaffin cells, 1.5% of neonatal cells, and 0.1% of adult cells. Addition of 10 nM IGF-I or IGF-II increased the fraction of BrdUrd-labeled nuclei to 50% of fetal, 20% of neonatal, and 2% of adult chromaffin cells. The ED50 value of IGF-I- and IGF-II-stimulated BrdUrd labeling in neonatal chromaffin cells was 0.3 nM and 0.8 nM, respectively. In neonatal and adult chromaffin cells, addition of 1 nM bFGF or 2 nM NGF stimulated nuclear BrdUrd incorporation to approximately the same level as 10 nM IGF-I or IGF-II. However, the response to bFGF or NGF in combination with either IGF-I or IGF-II was more than additive, indicating that the combined effect of the IGFs and bFGF or NGF is synergistic. The degree of synergism was 2- to 4-fold in neonatal chromaffin cells and 10- to 20-fold in adult chromaffin cells compared with the effect of each growth factor alone. In contrast, the action of bFGF and NGF added together in the absence of IGFs was not synergistic or additive. IGF-II acted also as a survival factor on neonatal chromaffin cells and the cell survival was further improved when bFGF or NGF was added together with IGF-II. In conclusion, we propose that IGF-I and IGF-II act in synergy with bFGF and NGF to stimulate proliferation and survival of chromaffin cells during neonatal growth and adult maintenance of the adrenal medulla. Our findings may have implications for improving the survival of chromaffin cell implants in diseased human brain. PMID:8127879

  9. The granulin-epithelin precursor/PC-cell-derived growth factor is a growth factor for epithelial ovarian cancer.

    PubMed

    Jones, Monica Brown; Michener, Chad M; Blanchette, James O; Kuznetsov, Vladimir A; Raffeld, Mark; Serrero, Ginette; Emmert-Buck, Michael R; Petricoin, Emanuel F; Krizman, David B; Liotta, Lance A; Kohn, Elise C

    2003-01-01

    The role of growth factors in ovarian cancer development and progression is complex and multifactorial. We hypothesized that new growth factors may be identified through the molecular analysis of ovarian tumors as they exist in their native environment. RNA extracted from microdissected serous low malignant potential (LMP) and invasive ovarian tumors was used to construct cDNA libraries. A total of 7300 transcripts were randomly chosen for sequencing, and those transcripts were statistically evaluated. Reverse transcription-PCR and immunohistochemistry were used to validate the findings in tumor tissue samples. Ovarian cancer cell lines were used to test gene effects on monolayer growth, proliferative capacity, and density-independent growth. Analysis of the pooled library transcripts revealed 26 genes differentially expressed between LMP and invasive ovarian cancers. The granulin-epithelin precursor [GEP/PC-cell derived growth factor (PCDGF)] was expressed only in the invasive ovarian cancer libraries (P < 0.028) and was absent in the LMP libraries (0 of 2872 clones). All of the invasive tumor epithelia, 20% of the LMP tumor epithelia, and all of the stroma from both subsets expressed GEP by reverse transcription-PCR. Immunohistochemical staining for GEP was diffuse and cytosolic in invasive ovarian cancer tumor cells compared with occasional, punctate, and apical staining in LMP tumor epithelia. Antisense transfection of GEP into ovarian cancer cell lines resulted in down-regulation of GEP production, reduction in cell growth (P < 0.002), decrease in the S-phase fraction (P < 0.04), and loss of density-independent growth potential (P < 0.01). cDNA library preparation from microdissected tumor epithelium provided a selective advantage for the identification of growth factors for epithelial ovarian cancer. Differential granulin expression in tumor samples and the antiproliferative effects of its antisense down-regulation suggest that GEP may be a new autocrine

  10. Interactions between fibroblast growth factors and Notch regulate neuronal differentiation.

    PubMed

    Faux, C H; Turnley, A M; Epa, R; Cappai, R; Bartlett, P F

    2001-08-01

    The differentiation of precursor cells into neurons has been shown to be influenced by both the Notch signaling pathway and growth factor stimulation. In this study, the regulation of neuronal differentiation by these mechanisms was examined in the embryonic day 10 neuroepithelial precursor (NEP) population. By downregulating Notch1 expression and by the addition of a Delta1 fusion protein (Delta Fc), it was shown that signaling via the Notch pathway inhibited neuron differentiation in the NEP cells, in vitro. The expression of two of the Notch receptor homologs, Notch1 and Notch3, and the ligand Delta1 in these NEP cells was found to be influenced by a number of different growth factors, indicating a potential interaction between growth factors and Notch signaling. Interestingly, none of the growth factors examined promoted neuron differentiation; however, the fibroblast growth factors (FGFs) 1 and 2 potently inhibited differentiation. FGF1 and FGF2 upregulated the expression of Notch and decreased expression of Delta1 in the NEP cells. In addition, the inhibitory response of the cells to the FGFs could be overcome by downregulating Notch1 expression and by disrupting Notch cleavage and signaling by the ablation of the Presenilin1 gene. These results indicate that FGF1 and FGF2 act via the Notch pathway, either directly or indirectly, to inhibit differentiation. Thus, signaling through the Notch receptor may be a common regulator of neuronal differentiation within the developing forebrain.

  11. 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

  12. Viability and growth of feline preantral follicles in vitro cultured with insulin growth factor and epidermal growth factor supplemented medium.

    PubMed

    Alves, A E; Padilha-Nakaghi, L C; Pires-Butler, E A; Apparicio, M; Silva, Nam; Motheo, T F; Vicente, Wrr; Luvoni, G C

    2017-04-01

    In vitro culture of ovarian preantral follicles has emerged as a reproductive technology aimed at obtaining large amount of oocytes for in vitro embryo production. The addition of growth factors (GF) in the in vitro culture of preantral follicles of different species has provided superior results of follicular development, antrum formation and proliferation of granulosa cells. However, there are only few reports regarding the use of these factors on feline preantral follicle in vitro culture. Thus, the aim of this study was to investigate the effect of a combination of IGF-1 and EGF on in vitro viability and growth of preantral follicles and enclosed oocytes collected from domestic cats. A total of 64 follicles characterized by multilayer granulosa cells were isolated and individually cultured for 6 days (T6) in minimum essential medium supplemented with IGF-1+ EGF (100 ng/ml each) or without (control). A higher percentage of follicles were viable after culture with GF than without, and an increase in size when IGF-1+ EGF were added to the medium (170 ± 32.4 μm (T0) vs. 201 ± 22.3 μm (T6); p < .05) was observed. An increase in the diameter was also observed in follicles cultured without GF, but this increase was only 8.3% compared to 15.4% of those cultured with GF (p < .05). No differences were found in the diameter of oocytes contained in follicles cultured in the non-supplemented or supplemented media (107.9 ± 11.8 μm (T0) vs. 113.2 ± 15.6 μm (T6); p > .05). These data suggest that the addition of IGF-1 and EGF to the culture medium promotes the in vitro development of preantral follicles of cats. © 2016 Blackwell Verlag GmbH.

  13. Cytokine and Growth Factor Responses After Radiotherapy for Localized Ependymoma

    SciTech Connect

    Merchant, Thomas E. Li Chenghong; Xiong Xiaoping; Gaber, M. Waleed

    2009-05-01

    Purpose: To determine the time course and clinical significance of cytokines and peptide growth factors in pediatric patients with ependymoma treated with postoperative radiotherapy (RT). Methods and Materials: We measured 15 cytokines and growth factors (fibroblast growth factor, epidermal growth factor, vascular endothelial growth factor [VEGF], interleukin [IL]-1{beta}, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, interferon-{gamma}, tumor necrosis factor-{alpha}, granulocyte-macrophage colony-stimulating factor, monocyte chemoattractant protein-1, and macrophage inflammatory protein-{alpha}) from 30 patients before RT and 2 and 24 h, weekly for 6 weeks, and at 3, 6, 9, and 12 months after the initiation of RT. Two longitudinal models for the trend of log-transformed measurements were fitted, one during treatment and one through 12 months. Results: During RT, log IL-8 declined at a rate of -0.10389/wk (p = 0.0068). The rate of decline was greater (p = 0.028) for patients with an infratentorial tumor location. The decline in IL-8 after RT was significant when stratified by infratentorial tumor location (p = 0.0345) and more than one surgical procedure (p = 0.0272). During RT, the decline in log VEGF was significant when stratified by the presence of a ventriculoperitoneal shunt. After RT, the log VEGF declined significantly at a rate of -0.06207/mo. The decline was significant for males (p = 0.0222), supratentorial tumors (p = 0.0158), one surgical procedure (p = 0.0222), no ventriculoperitoneal shunt (p = 0.0005), and the absence of treatment failure (p = 0.0028). Conclusion: The pro-inflammatory cytokine IL-8 declined significantly during RT and the decline differed according to tumor location. The angiogenesis factor VEGF declined significantly during the 12 months after RT. The decline was greater in males, those without a ventriculoperitoneal shunt, and in those with favorable disease factors, including one surgical procedure, supratentorial tumor location, and

  14. Insulin-like growth factor I acts as an angiogenic agent in rabbit cornea and retina: comparative studies with basic fibroblast growth factor.

    PubMed

    Grant, M B; Mames, R N; Fitzgerald, C; Ellis, E A; Aboufriekha, M; Guy, J

    1993-04-01

    The release of growth factors from ischaemic retina has been hypothesized as the central stimulus for retinal neovascularization in proliferative diabetic retinopathy. Two of the growth factors implicated are insulin-like growth factor-I and basic fibroblast growth factor. We examined the effect of insulin-like growth factor-I on in vivo neovascularization using the established angiogenic model of the rabbit cornea (n = 30), and also compared the effects of insulin-like growth factor-I and basic fibroblast growth factor using two new in vivo systems. Either supraphysiologic concentrations of each growth factor (600 micrograms) were injected intravitreally into pigmented rabbits (n = 21) or porous polyfluorotetraethylene chambers filled with an emulsion containing collagen and growth factor (500 ng) were placed on the retina surface (n = 8). Our results demonstrate that when insulin-like growth factor-I was implanted together with a slow release carrier into the pocket of the normally avascular cornea, insulin-like growth factor-I (10 micrograms/pellet) induced angiogenesis in all rabbits. This degree of angiogenesis was comparable to that previously shown for basic fibroblast growth factor. For the intravitreal studies, the fibrotic component was greater in the basic fibroblast growth factor injected eyes, whereas the vascular component was accentuated in the eyes injected with insulin-like growth factor-I. Light and electron microscopy demonstrated areas of vascular proliferation in both groups. Porous polyfluorotetraethylene chamber studies with insulin-like growth factor-I and basic fibroblast growth factor demonstrated vascular proliferation in the vicinity of the chamber similar to the intravitreal injected eyes, but to a lesser degree than the injected eyes. Our experiments overall support the angiogenic potential of both insulin-like growth factor-I and basic fibroblast growth factor and support distinct but complimentary roles for each growth factor in the

  15. 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

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

    PubMed Central

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

    2013-01-01

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

  17. Advances in growth factor delivery for therapeutic angiogenesis.

    PubMed

    Said, Somiraa S; Pickering, J Geoffrey; Mequanint, Kibret

    2013-01-01

    Therapeutic angiogenesis is a new revascularization strategy involving the administration of growth factors to induce new vessel formation. The biology and delivery of angiogenic growth factors involved in vessel formation have been extensively studied but success in translating the angiogenic capacity of growth factors into benefits for vascular disease patients is still limited. This could be attributed to issues related to patient selection, growth factor delivery methods or lack of vessel maturation. Comprehensive understanding of the cellular and molecular cross-talk during the different stages of vascular development is needed for the design of efficient therapeutic strategies. The presentation of angiogenic factors either in series or in parallel using a strategy that mimics physiological events, such as concentration and spatio-temporal profiles, is an immediate requirement for functional blood vessel formation. This review provides an overview of the recent delivery strategies of angiogenic factors and discusses targeting neovascular maturation as a promising approach to induce stable and functional vessels for therapeutic angiogenesis.

  18. 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.

  19. Growth factors with heparin binding affinity in human synovial fluid

    SciTech Connect

    Hamerman, D.; Taylor, S.; Kirschenbaum, I.; Klagsbrun, M.; Raines, E.W.; Ross, R.; Thomas, K.A.

    1987-12-01

    Synovial effusions were obtained from the knees of 15 subjects with joint trauma, menisceal or ligamentous injury, or osteoarthritis. Heparin-Sepharose affinity chromatography of these synovial fluids revealed, in general, three major peaks of mitogenic activity as measured by incorporation of /sup 3/H-thymidine into 3T3 cells. Gradient elution patterns showed activities at 0.5M NaCl, which is characteristic of platelet derived growth factor, and at 1.1 M NaCl and 1.6M NaCl, indicative of acidic and basic fibroblast growth factors, respectively. The identities of these mitogenic fractions were confirmed by specific immunologic and receptor-binding assays. The presence of platelet derived, acidic and basic fibroblast growth factors in the synovial fluid may contribute to wound healing in the arthritic joint.

  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. Heparin-conjugated gelatin as a growth factor immobilization scaffold.

    PubMed

    Nakamura, Shintaro; Kubo, Takafumi; Ijima, Hiroyuki

    2013-05-01

    Tissue engineering requires growth factors, cells and a scaffold to permit effective tissue regeneration. This study aimed to develop a scaffold with a focus on immobilizing growth factors within gelatin. We focused on the extracellular matrix and developed a heparin-conjugated gelatin (Hep-gela). Conjugation was confirmed using the alcian blue assay and X-ray diffraction patterns. The mechanical strength and stability of the Hep-gela gel in protease solution were improved compared with collagen gel. Hep-gela was able to immobilize vascular endothelial growth factor (VEGF) even in the presence of albumin, with an efficiency of 54.2%. Immobilized VEGF promoted proliferation of human umbilical vein endothelial cells. Hep-gela-immobilized VEGF maintained its native biological activity. In summary, Hep-gela has the potential to become an effective material in the field of regenerative medicine.

  2. Cultured human foreskin fibroblasts produce a factor that stimulates their growth with properties similar to basic fibroblast growth factor

    SciTech Connect

    Story, M.T. )

    1989-05-01

    To determine if fibroblasts could be a source of fibroblast growth factor (FGF) in tissue, cells were initiated in culture from newborn human foreskin. Fibroblast cell lysates promoted radiolabeled thymidine uptake by cultured quiescent fibroblasts. Seventy-nine percent of the growth-promoting activity of lysates was recovered from heparin-Sepharose. The heparin-binding growth factor reacted on immunoblots with antiserum to human placenta-derived basic FGF and competed with iodinated basic FGF for binding to antiserum to (1-24)bFGF synthetic peptide. To confirm that fibroblasts were the source of the growth factor, cell lysates were prepared from cells incubated with radiolabeled methionine. Heparin affinity purified material was immunoprecipitated with basic FGF antiserum and electrophoresed. Radiolabeled material was detected on gel autoradiographs in the same molecular weight region as authentic iodinated basic FGF. The findings are consistant with the notion that cultured fibroblasts express basic FGF. As these cells also respond to the mitogen, it is possible that the regulation of their growth is under autocrine control. Fibroblasts may be an important source of the growth factor in tissue.

  3. Insulin-like growth factors in the peripheral nervous system.

    PubMed

    Sakowski, Stacey A; Feldman, Eva L

    2012-06-01

    Insulin-like growth factors (IGFs) play an integral role in development, growth, and survival. This article details the current understanding of the effects of IGFs in the peripheral nervous system (PNS) during health and disease, and introduces how the IGF system regulates PNS development and impacts growth and survival of PNS cells. Also discussed are implications of IGF signaling in neurodegeneration and the status and prospects of IGF therapies for PNS conditions. There is substantial support for the application of IGF therapies in the treatment of PNS injury and disease.

  4. Heparin Binding Epidermal Growth Factor-Like Growth Factor Heals Chronic Tympanic Membrane Perforations With Advantage Over Fibroblast Growth Factor 2 and Epidermal Growth Factor in an Animal Model.

    PubMed

    Santa Maria, Peter Luke; Weierich, Kendall; Kim, Sungwoo; Yang, Yunzhi Peter

    2015-08-01

    That heparin binding epidermal growth factor-like growth factor (HB-EGF) heals chronic tympanic membrane (TM) perforations at higher rates than fibroblast growth factor 2 (FGF2) and epidermal growth factor (EGF) in an animal model. A nonsurgical treatment for chronic TM perforation would benefit those unable to access surgery or those unable to have surgery, as well as reducing the cost of tympanoplasty. Growth factor (GF) treatments have been reported in the literature with variable success with the lack of a suitable animal providing a major obstacle. The GFs were tested in a validated mouse model of chronic TM perforation. A bioabsorbable hydrogel polymer was used to deliver the GF at a steady concentration as it dissolved over 4 weeks. A control (polymer only, n = 18) was compared to polymer loaded with HB-EGF (5 μg/ml, n = 18), FGF2 (100 μg/ml, n = 19), and EGF (250 μg/ml, n = 19). Perforations were inspected at 4 weeks. The healing rates, as defined as 100% perforation closure, were control (5/18, 27.8%), HB-EGF (15/18, 83.3%), FGF2 (6/19, 31.6%), and EGF (3/19, 15.8%). There were no differences between FGF2 (p = 0.80) and EGF (p = 0.31) with control healing rates. HB-EGF (p = 0.000001) showed a significant difference for healing. The HB-EGF healed TMs showed layers similar to a normal TM, whereas the other groups showed a lack of epithelial migration. This study confirms the advantage of HB-EGF over two other commonly used growth factors and is a promising nonsurgical treatment of chronic TM perforations.

  5. 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.

  6. Growth factor delivery to re-engineer periodontal tissues.

    PubMed

    Anusaksathien, Orasa; Giannobile, William V

    2002-06-01

    Repair of tooth-supporting structures destroyed by the chronic inflammatory disease periodontitis is a major goal of oral therapy. The field of tissue engineering combines materials science and biology to repair tissues and organs. Periodontal tissue engineering has been achieved with limited success by the utilization of guiding tissue (cell occlusive) membranes and bone grafting techniques. Over the past decade investigators have begun to utilize signaling molecules such as growth factors to restore lost tooth support due to periodontitis, the most common bone disease affecting humans. This review will provide information on the status of growth factor therapies being applied in periodontology to treat advanced alveolar bone loss.

  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. 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.

  9. Cystine knot growth factors and their functionally versatile proregions.

    PubMed

    Schwarz, Elisabeth

    2017-09-05

    The cystine knot disulfide pattern has been found to be widespread in nature, since it has been detected in proteins from plants, marine snails, spiders and mammals. Cystine knot proteins are secreted proteins. Their functions range from defense mechanisms as toxins, e.g. ion channel or enzyme inhibitors, to hormones, blood factors and growth factors. Cystine knot proteins can be divided into two superordinate groups. (i) The cystine knot peptides, also referred to - with other non-cystine knot proteins - as knottins, with linear and cyclic polypeptide chains. (ii) The cystine knot growth factor family, which is in the focus of this article. The disulfide ring structure of the cystine knot peptides is made up by the half-cystines 1-4 and 2-5, and the threading disulfide bond is formed by the half-cystines, 3-6. In the growth factor group, the disulfides of half-cystines 1 and 4 pass the ring structure formed by the half-cystines 2-5 and 3-6. In this review, special emphasis will be devoted to the growth factor cystine knot proteins and their proregions. The latter have shifted into the focus of scientific interest as their important biological roles are just to be unravelled.

  10. Temperature affects insulin-like growth factor I and growth of juvenile southern flounder, Paralichthys lethostigma.

    PubMed

    Luckenbach, J Adam; Murashige, Ryan; Daniels, Harry V; Godwin, John; Borski, Russell J

    2007-01-01

    Temperature profoundly influences growth of heterothermic vertebrates. However, few studies have investigated the effects of temperature on growth and insulin-like growth factor I (IGF-I) in fishes. The aim of this study was to examine effects of temperature on growth and establish whether IGF-I may mediate growth at different temperatures in southern flounder, Paralichthys lethostigma. In two experiments, juvenile flounder were reared at 23 and 28 degrees C and growth was monitored for either 117 or 197 days. Growth was similar across treatments in both experiments until fish reached approximately 100 mm total length. Body size then diverged with fish at 23 degrees C ultimately growing 65-83% larger than those at 28 degrees C. Muscle IGF-I mRNA, plasma IGF-I, and hepatosomatic index (HSI) were significantly higher in flounder at 23 degrees C, whereas hepatic IGF-I mRNA abundance did not differ with treatment. Muscle IGF-I mRNA was correlated with HSI, while plasma IGF-I was correlated with body size, hepatic IGF-I mRNA, and HSI. These results demonstrate a strong effect of temperature on flounder growth and show that temperature-induced variation in growth is associated with differences in systemic IGF-I and local (i.e., muscle) IGF-I mRNA levels. The results also support the use of plasma IGF-I and HSI as indicators of flounder growth status.

  11. Growth Factor Liberation and DPSC Response Following Dentine Conditioning.

    PubMed

    Sadaghiani, L; Gleeson, H B; Youde, S; Waddington, R J; Lynch, C D; Sloan, A J

    2016-10-01

    Liberation of the sequestrated bioactive molecules from dentine by the action of applied dental materials has been proposed as an important mechanism in inducing a dentinogenic response in teeth with viable pulps. Although adhesive restorations and dentine-bonding procedures are routinely practiced, clinical protocols to improve pulp protection and dentine regeneration are not currently driven by biological knowledge. This study investigated the effect of dentine (powder and slice) conditioning by etchants/conditioners relevant to adhesive restorative systems on growth factor solubilization and odontoblast-like cell differentiation of human dental pulp progenitor cells (DPSCs). The agents included ethylenediaminetetraacetic acid (EDTA; 10%, pH 7.2), phosphoric acid (37%, pH <1), citric acid (10%, pH 1.5), and polyacrylic acid (25%, pH 3.9). Growth factors were detected in dentine matrix extracts drawn by EDTA, phosphoric acid, and citric acid from powdered dentine. The dentine matrix extracts were shown to be bioactive, capable of stimulating odontogenic/osteogenic differentiation as observed by gene expression and phenotypic changes in DPSCs cultured in monolayer on plastic. Polyacrylic acid failed to solubilize proteins from powdered dentine and was therefore considered ineffective in triggering a growth factor-mediated response in cells. The study went on to investigate the effect of conditioning dentine slices on growth factor liberation and DPSC behavior. Conditioning by EDTA, phosphoric acid, and citric acid exposed growth factors on dentine and triggered an upregulation in genes associated with mineralized differentiation, osteopontin, and alkaline phosphatase in DPSCs cultured on dentine. The cells demonstrated odontoblast-like appearances with elongated bodies and long extracellular processes extending on dentine surface. However, phosphoric acid-treated dentine appeared strikingly less populated with cells, suggesting a detrimental impact on cell

  12. 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.

  13. Marked stimulation of growth and motility of human keratinocytes by hepatocyte growth factor

    SciTech Connect

    Matsumoto, K.; Hashimoto, K.; Yoshikawa, K.; Nakamura, T. )

    1991-09-01

    Effect of hepatocyte growth factor (HGF) on normal human epidermal keratinocytes cultured under conditions of low Ca2+ (0.1 mM, growth-promoting condition) and physiological Ca2+ (1.8 mM, differentiation-promoting condition) was investigated. In low Ca2+, HGF markedly enhanced the migration of keratinocytes while it suppressed cell growth and DNA synthesis in a dose-dependent manner. In contrast, HGF enhanced the migration, cell growth, and DNA synthesis of keratinocytes cultured under conditions of physiological Ca2+. The maximal stimulation of DNA synthesis (2.4-fold stimulation) in physiological Ca2+ was seen at 2.5-5 ng/ml HGF and the stimulatory effect of HGF was suppressed by transforming growth factor-beta 1. Analysis of the HGF receptor using 125I-HGF as a ligand showed that human keratinocytes expressed a single class of specific, saturable receptor for HGF in both low and physiological Ca2+ conditions, exhibiting a Kd = 17.3 pM and approximately 690 binding sites/cell under physiological Ca2+. Thus, HGF is a potent factor which enhances growth and migration of normal human keratinocytes under conditions of physiological Ca2+. HGF may play an important role in epidermal tissue repair as it enhances both the migration and growth of keratinocytes.

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

    PubMed

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

    1999-09-01

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

  15. Maternal insulin-like growth factor binding protein-1, body mass index, and fetal growth

    PubMed Central

    Holmes, R.; Holly, J; Soothill, P.

    2000-01-01

    AIM—To examine the hypothesis that the maternal insulin-like growth factor system may constrain fetal growth.
METHODS—A prospective observational study of maternal serum insulin-like growth factor binding protein-1 (IGFBP-1) and fetal growth was undertaken in neonates with birthweights below the 5th centile. They had been classified either as having fetal growth restriction (FGR) due to placental dysfunction (increased umbilical artery Doppler pulsatility index (PI); n = 25) or as being small for gestational age (SGA; normal umbilical artery PI, growth velocity and amniotic fluid; n = 27). Eighty nine controls had normal birthweights (5th-95th centile), umbilical artery PI, growth velocity, and amniotic fluid. IGFBP-1 was measured by radioimmunoassay.
RESULTS—Among the controls, there was no significant correlation between IGFBP-1 and birthweight after allowing for body mass index (BMI). Maternal BMI was high in FGR and after adjusting for this, IGFBP-1 was increased (109 ng/ml) compared with SGA babies (69ng/ml) and controls (57 ng/ml) and correlated with the umbilical artery PI.
CONCLUSIONS—Maternal IGFBP-1 is probably not part of normal placental function. Its increase in FGR could be the cause or consequence of impaired placental perfusion, but high IGFBP-1 concentrations might further reduce the availability of maternal IGF-I to the placenta. This could worsen placental function and so adversely affect fetal growth.
 PMID:10685983

  16. Selective decrease in axonal nerve growth factor and insulin-like growth factor I immunoreactivity in axonopathies of unknown etiology.

    PubMed

    Fressinaud, Catherine; Jean, Isabelle; Dubas, Frédéric

    2003-05-01

    In an attempt to approach the mechanisms underlying axonopathies of unknown etiology, we have studied by immunocytochemistry the fate of several growth factors in eight of such cases that we had previously analyzed by morphometry and which were characterized by a decrease in neurofilaments and an increase in beta tubulin immunostaining. Here we establish that, contrary to beta tubulin, growth-associated protein43 (GAP-43) immunolabeling is not up-regulated in theses cases, correlating well with the failure of regeneration. Neurotrophin-3 (NT-3) and its receptor TrkC were not modified compared to controls (five cases). On the contrary, we observed in all cases a pronounced decrease in the number of fibers labeled for nerve growth factor (NGF) and insulin-like growth factor I (IGF-I), which were both approximately half of control values. This decrease could not be ascribed to the reduction in fiber density since it was also present in cases without fiber loss (isolated large fiber atrophy). The fact that only around 50% of fibers were stained, versus all fibers in controls, probably accounted for this decrease. It contrasted also with the normality of NGF and IGF-I immunolabeling in six cases of chronic inflammatory demyelinating neuropathy that were investigated in parallel. These results differ from those reported in experimental diabetic neuropathy, during which NT-3 is also decreased. A deficient supply of specific growth factors delivered by neuronal targets may be responsible for these neuropathies and their associated axonal cytoskeleton abnormalities.

  17. Therapeutic potential of growth factors and their antagonists.

    PubMed Central

    Garner, A.

    1992-01-01

    This article describes studies with four peptides, epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), gastrin-releasing peptide/bombesin (GRP), and gastrin. The mitogenic and anti-secretory activities of EGF/TGF alpha appear to be mediated by a single class of high-affinity membrane receptors but may involve different signal transducing mechanisms. Biological activity of EGF resides in the N-terminal 42 amino acid fragment with the C-terminal undecapeptide determining binding affinity. A parenteral depot formulation of an EGF-related peptide or a small molecule agonist of the EGF receptor could have utility in treating various ulcerative disorders of the gut. Although antagonism of EGF (and thus TGF alpha) receptors and/or transducing mechanisms is frequently cited as a potential therapeutic approach to hyperproliferative diseases, blocking the action of TGF alpha, GRP, or gastrin with neutralizing antibodies or receptor antagonists did not influence the growth of a wide range of solid tumors in nude mice. These findings suggest that, unless tumor growth displays absolute dependency on one particular mitogen, antagonism of a specific growth factor is unlikely to have great effect in cancer therapy. PMID:1341074

  18. Role of various cytokines and growth factors in pubertal development.

    PubMed

    Casazza, Krista; Hanks, Lynae J; Alvarez, Jessica A

    2010-01-01

    Historical data suggest that body composition is intricately involved in pubertal development. Progression through puberty is dependent on the interaction between the growth hormone-insulin-like growth factor-1 (GH-IGF-1) axis, reproductive and metabolic hormones as well as pro- and anti-inflammatory cytokines which induce alterations in feedback mechanisms and therefore mediate body composition and growth. Simultaneous increases in GH and IGF-1, and the concomitant changes in the hormonal milieu (i.e. reproductive hormones, testosterone and estrogen, and insulin)are the major contributors to anabolic effects seen throughout the pubertal transition, and are affected by various factors including (but not limited to) energy status and body composition. Orexigenic agents (i.e. ghrelin and leptin) also play a role at the level of the hypothalamus affecting not only energy intake, but also pubertal onset and progression. Effects of cytokines, many of which may be considered catabolic, extend beyond their traditionally viewed role involving the immune system, accompanying reproductive maturity further regulating aspects of energy and bone metabolism. As such, the signal(s) initiating the hypothalamic response that triggers puberty is likely reliant on a number of neural, metabolic and endocrine networks, all of which are at least partially influenced by pubertal growth factors, and act independently, antagonistically and/or synergistically to regulate anabolic pathways, therefore modifying body composition trajectory and growth during adolescence.

  19. 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.

  20. Growth factors/cytokines/defensins and apoptosis in periodontal pathologies.

    PubMed

    Laurina, Zane; Pilmane, Mara; Care, Ruta

    2009-01-01

    In the recent past there has been an increased emphasis on morphogenetic tissue research of periodontal tissues. The aim of this study was to find qualitative and quantitative correlations in distribution and appearance of growth factors/cytokines/defensins and apoptosis in periodontal pathologies. Tissue was obtained from 5 controls and 6 chronical periodontitis patients 30-50 years of age referred to Latvian Institute of Stomatology. Histological investigations were performed at the Institute of Anatomy and Anthropology of Riga Stradins University. Epithelial cells abundantly expressed IL10 in patients. The expression of b-defensins was very variable in both sulcular and gingival epithelium. TUNEL positive cells were observed in patients and control specimens with dominance in control group. Gingival epithelium showed moderate expression of bFGF whereas few to moderate cells were positive for bFGF in sulcular epithelium. Fibroblast growth factor receptor (FGF-1R) was abundant in gingival epithelium and in connective tissue cells, but almost not detectable in sulcular epithelium. Insulin-like growth factor receptor was not expressed in gingival epithelium and was weakly seen in basal layer of sulcular epithelium. Basic nerve growth factor expresion in both types of epithelium was numerous to abundant. Staining for the NGFR in the gingival epithelium was variable, with prevalence to be moderate whereas sulcular epithelium was free from any factor immunoreactivity. 1. Finding of apoptotic cells are variable and seems to correlate with the expression of defensins in oral epithelium in patients with periodontitis. 2. FGFR was expressed more than the bFGF, but in case with NGFR and bNGF situation was opposite. Although IGFRI was found in sulcular epithelium with no expression in gingival one suggesting about stimulation in regeneration/adaptation in periodontitis affected tissue. 3. The expression of growth factors and their receptors in sulcular epithelium was lower

  1. Heparin-Binding Epidermal Growth Factor-like Growth Factor/Diphtheria Toxin Receptor in Normal and Neoplastic Hematopoiesis

    PubMed Central

    Vinante, Fabrizio; Rigo, Antonella

    2013-01-01

    Heparin-binding EGF-like growth factor (HB-EGF) belongs to the EGF family of growth factors. It is biologically active either as a molecule anchored to the membrane or as a soluble form released by proteolytic cleavage of the extracellular domain. HB-EGF is involved in relevant physiological and pathological processes spanning from proliferation and apoptosis to morphogenesis. We outline here the main activities of HB-EGF in connection with normal or neoplastic differentiative or proliferative events taking place primitively in the hematopoietic microenvironment. PMID:23888518

  2. 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

  3. Role of fibroblast growth factors in organ regeneration and repair.

    PubMed

    El Agha, Elie; Kosanovic, Djuro; Schermuly, Ralph T; Bellusci, Saverio

    2016-05-01

    In its broad sense, regeneration refers to the renewal of lost cells, tissues or organs as part of the normal life cycle (skin, hair, endometrium etc.) or as part of an adaptive mechanism that organisms have developed throughout evolution. For example, worms, starfish and amphibians have developed remarkable regenerative capabilities allowing them to voluntarily shed body parts, in a process called autotomy, only to replace the lost parts afterwards. The bizarre myth of the fireproof homicidal salamander that can survive fire and poison apple trees has persisted until the 20th century. Salamanders possess one of the most robust regenerative machineries in vertebrates and attempting to draw lessons from limb regeneration in these animals and extrapolate the knowledge to mammals is a never-ending endeavor. Fibroblast growth factors are potent morphogens and mitogens that are highly conserved among the animal kingdom. These growth factors play key roles in organogenesis during embryonic development as well as homeostatic balance during postnatal life. In this review, we provide a summary about the current knowledge regarding the involvement of fibroblast growth factor signaling in organ regeneration and repair. We also shed light on the use of these growth factors in previous and current clinical trials in a wide array of human diseases.

  4. 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.

  5. The Study of the Enrollment Growth Factor. Final Report.

    ERIC Educational Resources Information Center

    Whitney, Terry N.; And Others

    This paper presents findings of a study that examined the New Mexico school-finance formula. Specifically, the study assessed the adequacy of the enrollment growth factor (EGF) and its differential impact on New Mexico school districts that grow at different rates. An EGF refers to some type of weighting in a state's basic aid formula to reflect…

  6. Sulodexide induces hepatocyte growth factor release in humans.

    PubMed

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

    2007-03-08

    Heparin influences numerous pleiotropic growth factors, including hepatocyte growth factor (HGF), partially by their release from endothelial and extracellular matrix stores. The effects of sulodexide, a heparin-like glycosaminoglycan medication of growing importance in medicine, on HGF liberation are not known. We performed a 2-week open-label sulodexide trial in healthy male volunteers. The drug was initially administered intravenously (i.v.) in a single dose of 1200 Lipoprotein Lipase Releasing Units (LRU), then -- orally for 12 days (500 LRU twice a day), and -- again by i.v. route (1200 LRU) on day 14. Intravenous sulodexide injections were repeatedly found to induce marked and reproducible increases in immunoreactive plasma HGF levels (more than 3500% vs baseline after 10 min, and more than 1200% after 120 min), and remained unchanged when measured 120 min following oral sulodexide administration. The percentage increments in plasma HGF evoked by i.v. sulodexide at both time points and on both days inversely correlated with baseline levels of the growth factor. On day 14, the HGF levels after 120 min and their percentage increase vs baseline were strongly and directly dependent on i.v. sulodexide dose per kg of body weight. This study shows that sulodexide has a novel, remarkable and plausibly biologically important stimulating effect on the release of pleiotropic hepatocyte growth factor in humans.

  7. 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

  8. Fibroblast Growth Factor-2 Alters the Nature of Extinction

    ERIC Educational Resources Information Center

    Graham, Bronwyn M.; Richardson, Rick

    2011-01-01

    These experiments examined the effects of the NMDA-receptor (NMDAr) antagonist MK801 on reacquisition and re-extinction of a conditioned fear that had been previously extinguished before injection of fibroblast growth factor-2 (FGF2) or vehicle. Recent findings have shown that relearning and re-extinction, unlike initial learning and extinction,…

  9. Fibroblast Growth Factor-2 Alters the Nature of Extinction

    ERIC Educational Resources Information Center

    Graham, Bronwyn M.; Richardson, Rick

    2011-01-01

    These experiments examined the effects of the NMDA-receptor (NMDAr) antagonist MK801 on reacquisition and re-extinction of a conditioned fear that had been previously extinguished before injection of fibroblast growth factor-2 (FGF2) or vehicle. Recent findings have shown that relearning and re-extinction, unlike initial learning and extinction,…

  10. 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

  11. 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.

  12. Auxins as one of the factors of plant growth improvement by plant growth promoting rhizobacteria.

    PubMed

    Ahmed, Ambreen; Hasnain, Shahida

    2014-01-01

    Plant growth promoting rhizobacteria (PGPR) promote plant growth by various mechanisms such as phytohormone production, enhanced water and nutrient uptake, improved nitrogen availability in the soil, production of ACC-deaminase for ethylene breakdown, phosphate solubilization, siderophore production etc. Microbial auxin production is the major factor not only responsible for strengthening the plant-microbe relationship but it also promotes plant growth and development in a positive manner. Thus, bacterial auxin production potential can be exploited for plant growth improvement that may be effective in reducing the hazardous effects of chemical fertilizers on the ecosystem used to obtain higher yields. The present review gives a better understanding of various factors and mechanisms involved in auxin production by PGPR that may be helpful in proper exploitation of these natural resources in a beneficial way.

  13. Steady impact factor growth for MDPI open access journals.

    PubMed

    Thiesen, Alexander

    2012-09-12

    For the past three years MDPI has announced the newly released impact factors for its Open Access journals by the means of an annual editorial [1-3]. In 2012 we are-once again-pleased to report that the growth of the impact factors of MDPI's Open Access journals continues. This year's edition of the Journal Citation Reports (JCR), which is published annually by Thomson Reuters, includes 10 journals published by MDPI, including three that have received their first official Impact Factors- International Journal of Environmental Research and Public Health (IJERPH), Materials Nutrients. Table 1 reports the latest Impact Factors for 2011. Figure 1 graphically depicts the evolution of the Impact Factors for four MDPI open access journals that have received Impact Factors in the past. Table 2 reports the ranking of the MDPI journals within the subject categories of the Science Citation Index Expanded.

  14. Quantitative proteomics of fractionated membrane and lumen exosome proteins from isogenic metastatic and nonmetastatic bladder cancer cells reveal differential expression of EMT factors.

    PubMed

    Jeppesen, Dennis Kjølhede; Nawrocki, Arkadiusz; Jensen, Steffen Grann; Thorsen, Kasper; Whitehead, Bradley; Howard, Kenneth A; Dyrskjøt, Lars; Ørntoft, Torben Falck; Larsen, Martin R; Ostenfeld, Marie Stampe

    2014-03-01

    Cancer cells secrete soluble factors and various extracellular vesicles, including exosomes, into their tissue microenvironment. The secretion of exosomes is speculated to facilitate local invasion and metastatic spread. Here, we used an in vivo metastasis model of human bladder carcinoma cell line T24 without metastatic capacity and its two isogenic derivate cell lines SLT4 and FL3, which form metastases in the lungs and liver of mice, respectively. Cultivation in CLAD1000 bioreactors rather than conventional culture flasks resulted in a 13- to 16-fold increased exosome yield and facilitated quantitative proteomics of fractionated exosomes. Exosomes from T24, SLT4, and FL3 cells were partitioned into membrane and luminal fractions and changes in protein abundance related to the gain of metastatic capacity were identified by quantitative iTRAQ proteomics. We identified several proteins linked to epithelial-mesenchymal transition, including increased abundance of vimentin and hepatoma-derived growth factor in the membrane, and casein kinase II α and annexin A2 in the lumen of exosomes, respectively, from metastatic cells. The change in exosome protein abundance correlated little, although significant for FL3 versus T24, with changes in cellular mRNA expression. Our proteomic approach may help identification of proteins in the membrane and lumen of exosomes potentially involved in the metastatic process.

  15. 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

  16. Expression of protooncogenes during lymphocyte activation by growth factors.

    PubMed

    Bulanova, E G; Budagyan, V M; Yarilin, A A; Mazurenko, N N

    1997-09-01

    Effects of growth factors of non-immune origin including somatotropin (ST) and platelet-derived growth factor (PDGF) on the expression of the proteins encoded by c-fos, c-myc, c-fun, and c-ets family protooncogenes were studied for the first time. The dynamics of the oncoprotein expression in activated CD(3+)-lymphocytes was investigated by immunoblotting. The accumulation of the Fos and Myc proteins was enhanced in T-lymphocytes treated with ST, PDGF, or phytohemagglutinin; the accumulation was maximum at 30-60 min and decreased in 2 h; the data indicate that the oncoproteins participate in the early lymphocyte activation by various growth factors. The Jun protein appears only in 3 h after the onset of lymphocyte activation; this suggests independent participation of Fos in the early stages of lymphocyte activation prior to the appearance of Jun, preceding the joint action of Fos and Jun within the AP-1 transcription complex. The products of the c-ets family are differentially activated by the studied growth factors. Resting lymphocytes actively accumulate the Ets-1 protein; ST and PDGF activation decreases Ets-1 expression in 2 h. The Ets-2 protein is not detected in resting cells and PDGF-activated lymphocytes, whereas lymphocyte activation by ST is associated with accumulation of Ets-2. The data suggest that the product of the c-ets-1 gene is more important in the regulation of resting cells and the product of the c-ets-2 gene is important during activation of lymphocytes by ST. The results indicate that activation of lymphocytes with growth factors of non-immune origin is mediated by several signal transduction pathways.

  17. Role of hypoxia and vascular endothelial growth factors in lymphangiogenesis

    PubMed Central

    Morfoisse, Florent; Renaud, Edith; Hantelys, Fransky; Prats, Anne-Catherine; Garmy-Susini, Barbara

    2014-01-01

    Hypoxia is known to be a major factor in the induction of angiogenesis during tumor development but its role in lymphangiogenesis remains unclear. Blood and lymphatic vasculatures are stimulated by the vascular endothelial family of growth factors – the VEGFs. In this review, we investigate the role of hypoxia in the molecular regulation of synthesis of the lymphangiogenic growth factors VEGF-A, VEGF-C, and VEGF-D. Gene expression can be regulated by hypoxia at either transcriptional or translational levels. In contrast to strong induction of DNA transcription by hypoxia-inducible factors (HIFs), the majority of cellular stresses such as hypoxia lead to inhibition of cap-dependent translation of mRNA and downregulation of protein synthesis. Here, we describe how initiation of translation of VEGF mRNA is induced by hypoxia through an internal ribosome entry site (IRES)-dependent mechanism. Considering the implications of the lymphatic vasculature for metastatic dissemination, it is crucial to understand the molecular regulation of lymphangiogenic growth factors by hypoxia to obtain new insights into cancer therapy. PMID:27308316

  18. [Nerve growth factor in neurodegeneration and neurorestorative therapy].

    PubMed

    Lorigados-Pedre, L; Bergado-Rosado, J

    The purpose of this work was to gather the information currently available about the content of nerve growth factor (NGF) in experimental models of neurodegeneration and in neurodegenerative diseases, including Alzheimer's, Parkinson's and Huntington's diseases, as well as to analyse how NGF content is affected by the application of different neurorestorative therapies (transplant and trophic therapy) in these neurological entities. Neurotrophins are proteins that promote the differentiation, growth and survival of many populations of peripheral neurons and the central nervous system during development and adulthood. NGF is the best known and most widely researched member of this family, which is also made up of the growth factor derived from the brain and neurotrophins 3, 4/5, 6 and 7. In the last few decades, significant progress has been made in the knowledge available about the biological role played by these factors, their molecular characterisation and regulation, as well as their signalling mechanisms. Yet, little is known about the role played by the neurotrophic factors in neurodegenerative diseases or whether the levels of these factors are modified following the use of neurorestorative treatment. Neurodegenerative disorders, especially Parkinson and Alzheimer, are accompanied by modifications in the levels of NGF that depend on the extent to which the disease has progressed. A model of the changes in NGF content during neurodegenerative processes is also proposed.

  19. Hepatocyte growth factor counteracts transforming growth factor-beta1, through attenuation of connective tissue growth factor induction, and prevents renal fibrogenesis in 5/6 nephrectomized mice.

    PubMed

    Inoue, Tsutomu; Okada, Hirokazu; Kobayashi, Tatsuya; Watanabe, Yusuke; Kanno, Yoshihiko; Kopp, Jeffrey B; Nishida, Takashi; Takigawa, Masaharu; Ueno, Munehisa; Nakamura, Toshikazu; Suzuki, Hiromichi

    2003-02-01

    We investigated the mechanism of the anti-fibrotic effects of hepatocyte growth factor (HGF) in the kidney, with respect to its effect on connective tissue growth factor (CTGF), a down-stream, profibrotic mediator of transforming growth factor-beta1 (TGF-beta1). In wild-type (WT) mice with 5/6 nephrectomy (Nx), HGF and TGF-beta1 mRNAs increased transiently in the remnant kidney by week 1 after the Nx, returned to baseline levels, and increased again at weeks 4 to 12. In contrast, CTGF and alpha1(I) procollagen (COLI) mRNAs increased in parallel with HGF and TGF-beta1 during the early stage, but did not re-increase during the late stage. In the case of TGF-beta1 transgenic (TG) mice with 5/6 Nx, excess TGF-beta1 derived from the transgene enhanced CTGF expression significantly in the remnant kidney, accordingly accelerating renal fibrogenesis. Administration of dHGF (5.0 mg/kg/day) to TG mice with 5/6 Nx for 4 weeks from weeks 2 to 6 suppressed CTGF expression in the remnant kidney, attenuating renal fibrosis and improving the survival rate. In an experiment in vitro, renal tubulointerstitial fibroblasts (TFB) were co-cultured with proximal tubular epithelial cells (PTEC). Pretreatment with HGF reduced significantly CTGF induction in PTEC by TGF-beta1, consequently suppressing COLI synthesis in TFB. In conclusion, HGF can block, at least partially, renal fibrogenesis promoted by TGF-beta1 in the remnant kidney, via attenuation of CTGF induction.

  20. Vascular Endothelial growth factor signaling in hypoxia and Inflammation

    PubMed Central

    Ramakrishnan, S.; Anand, Vidhu; Roy, Sabita

    2014-01-01

    Infection, cancer and cardiovascular diseases are the major causes for morbidity and mortality in the United States according to the Center for Disease Control. The underlying etiology that contributes to the severity of these diseases is either hypoxia induced inflammation or inflammation resulting in hypoxia. Therefore, molecular mechanisms that regulate hypoxia-induced adaptive responses in cells are important areas of investigation. Oxygen availability is sensed by molecular switches which regulate synthesis and secretion of growth factors and inflammatory mediators. As a consequence, tissue microenvironment is altered by reprogramming metabolic pathways, angiogenesis, vascular permeability, pH homeostasis to facilitate tissue remodeling. Hypoxia inducible factor (HIF) is the central mediator of hypoxic response. HIF regulates several hundred genes and vascular endothelial growth factor (VEGF) is one of the primary target genes. Understanding the regulation of HIF and its influence on inflammatory response offers unique opportunities for drug development to modulate inflammation and ischemia in pathological conditions. PMID:24610033

  1. [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.

  2. Induction of nerve growth factor receptors on cultured human melanocytes

    SciTech Connect

    Peacocke, M.; Yaar, M.; Mansur, C.P.; Chao, M.V.; Gilchrest, B.A. )

    1988-07-01

    Normal differentiation and malignant transformation of human melanocytes involve a complex series of interactions during which both genetic and environmental factors play roles. At present, the regulation of these processes is poorly understood. The authors have induced the expression of nerve growth factor (NGF) receptors on cultured human melanocytes with phorbol 12-tetradecanoate 13-acetate and have correlated this event with the appearance of a more differentiated, dendritic morphology. Criteria for NGF receptor expression included protein accumulation and cell-surface immunofluorescent staining with a monoclonal antibody directed against the human receptor and induction of the messenger RNA species as determined by blot-hybridization studies. The presence of the receptor could also be induced by UV irradiation or growth factor deprivation. The NGF receptor is inducible in cultured human melanocytes, and they suggest that NGF may modulate the behavior of this neural crest-derived cell in the skin.

  3. Expression of the angiogenic factors vascular endothelial cell growth factor, acidic and basic fibroblast growth factor, tumor growth factor beta-1, platelet-derived endothelial cell growth factor, placenta growth factor, and pleiotrophin in human primary breast cancer and its relation to angiogenesis.

    PubMed

    Relf, M; LeJeune, S; Scott, P A; Fox, S; Smith, K; Leek, R; Moghaddam, A; Whitehouse, R; Bicknell, R; Harris, A L

    1997-03-01

    Angiogenesis is a significant prognostic factor in breast cancer, but the factors that control angiogenesis in vivo are not well defined. Multiple angiogenic polypeptides are known, and we have determined the expression of seven of these in primary human breast cancers; the relationship of expression to estrogen receptor and vascular density was also examined. Vascular endothelial growth factor (VEGF) and its four isoforms (121, 165, 189, and 206 amino acids), transforming growth factor (TGF)-beta1, pleiotrophin, acidic and basic fibroblast growth factor (FGF), placental growth factor, and thymidine phosphorylase (platelet-derived endothelial cell growth factor) were quantitated by RNase protection analysis. beta-FGF was also measured by ELISA. The estrogen receptor (ER), epidermal growth factor receptor, and vascular density were analyzed in 64 primary breast cancers. All tumors expressed at least six different vascular growth factors. VEGF was most abundant, and the transcript for the 121-amino acid form predominated. Other angiogenic factors expressed at high levels were thymidine phosphorylase and TGF-beta1. Expression of most of the angiogenic factors did not correlate with that of ER or vascular density. However, thymidine phosphorylase did, with a correlation coefficient of 0.3 (P = 0.03). There were significant associations of pleiotrophin with acidic FGF expression (P = 0.001) and TGF-beta with platelet-derived endothelial cell growth factor expression (P = 0.001). Thus, angiogenesis may involve a coordinate regulation of some vascular growth factors. High VEGF expression correlated with poor prognosis in univariate analysis (P = 0.03), as did ER and epidermal growth factor receptor expression. Basic FGF was also assessed by ELISA and was more highly expressed in tumors than normal breast tissues (median, 346 microg/ml cytosol; range, 54-1323 versus median, 149; range, 32-509; P = 0.01). Implications for therapy are that broad spectrum agents that block

  4. Vascular endothelial growth factor, basic fibroblast growth factor, insulin-like growth factor-I and platelet-derived growth factor levels in human milk of mothers with term and preterm neonates.

    PubMed

    Ozgurtas, Taner; Aydin, Ibrahim; Turan, Ozden; Koc, Esin; Hirfanoglu, Ibrahim Murat; Acikel, Cengiz Han; Akyol, Mesut; Erbil, M Kemal

    2010-05-01

    Human milk is a complex biological fluid. It contains many nutrients, anti-infectious and biologically active substance. Human milk also contains many angiogenic polypeptides. We have determined four of these: Vascular endothelial growth factor (VEGF), basic fibroblast growth factor (b-FGF), insulin-like growth factor- I (IGF-I) and platelet-derived growth factor (PDGF). The aim of this study was to compare the concentrations of VEGF, b-FGF, IGF-I and PDGF in human milk collected from mothers with preterm and term neonates. Human milk samples were collected from 29 mothers of preterm (<37 weeks) and from 29 mothers of term (38>weeks) infants at days 3, 7 and 28 postpartum. Milk samples were analyzed for VEGF, b-FGF and PDGF by enzyme-linked immunosorbent assay and IGF-I was measured by radioimmunoassay method. Human milk levels of VEGF, IGF-I and b-FGF were significantly higher (p<0.001). Furthermore, within-preterm group concentrations of VEGF, IGF-I and PDGF significantly differed during postpartum days 3-7-28 (p<0.001, p<0.05, p<0.001, respectively), but did not do so for b-FGF concentrations. In term groups, concentrations of IGF-I and VEGF significantly differed (p<0.05, p<0.001, respectively), but did not do so for concentrations of b-FGF and PDGF. This is the first report of simultaneous measurements of four major angiogenic factors in human milk collected from mothers with preterm and term. Our results suggest that three of four angiogenic factors, VEGF, b-FGF and IGF-I, are higher concentration in human milk which collected from preterm mothers than those of terms.

  5. Osteoinductive small molecules: growth factor alternatives for bone tissue engineering.

    PubMed

    Aravamudhan, Aja; Ramos, Daisy M; Nip, Jonathan; Subramanian, Aditi; James, Roshan; Harmon, Matthew D; Yu, Xiaojun; Kumbar, Sangamesh G

    2013-01-01

    Tissue engineering aims to repair, restore, and regenerate lost or damaged tissues by using biomaterials, cells, mechanical forces and factors (chemical and biological) alone or in combination. Growth factors are routinely used in the tissue engineering approach to expedite the process of regeneration. The growth factor approach has been hampered by several complications including high dose requirements, lower half-life, protein instability, higher costs and undesired side effects. Recently a variety of alternative small molecules of both natural and synthetic origin have been explored as alternatives to growth factors for tissue regeneration applications. Small molecules are simple biochemical components that elicit certain cellular responses through signaling cascades. Small molecules present a viable alternative to biological factors. Small molecule strategies can reduce various side effects, maintain bioactivity in a biological environment and minimize cost issues associated with complex biological growth factors. This manuscript focuses on three-osteoinductive small molecules, namely melatonin, resveratrol (from natural sources) and purmorphamine (synthetically designed) as inducers of bone formation and osteogenic differentiation of stem cells. Efforts have been made to summarize possible biological pathways involved in the action of each of these drugs. Melatonin is known to affect Mitogen Activated Protein (MAP) kinase, Bone morphogenic protein (BMP) and canonical wnt signaling. Resveratrol is known to activate cascades involving Wnt and NAD-dependent deacetylase sirtuin-1 (Sirt1). Purmorphamine is a Hedgehog (Hh) pathway agonist as it acts on Smoothened (Smo) receptors. These mechanisms and the way they are affected by the respective small molecules will also be discussed in the manuscript.

  6. 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.

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

    PubMed

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

    2016-05-01

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

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

    DTIC Science & Technology

    2004-01-01

    AE, Bansal R (1993) The oligodendrocyte and its many cellular processes. Trends Cell Biol 3:191-197. Pluchino S, Quattrini A, Brambilla E, Gritti A...Rosenberg D, Cheung SW, Mobley WC, Fisher S, Genain CP (2000) Human nerve growth factor protects common 141 marmosets against autoimmune

  9. Vascular growth factors and receptors in capillary hemangioblastomas and hemangiopericytomas.

    PubMed Central

    Hatva, E.; Böhling, T.; Jääskeläinen, J.; Persico, M. G.; Haltia, M.; Alitalo, K.

    1996-01-01

    Capillary hemangioblastomas and hemangiopericytomas are highly vascular central nervous system tumors of controversial origin. Of interest in their pathogenesis are mechanisms regulating endothelial cell growth. The endothelial cell mitogen vascular endothelial growth factor (VEGF) stimulates angiogenesis, and together with its two receptor tyrosine kinases VEGFR-1(FLT1) and VEGFR-2(KDR), is up-regulated during the malignant progression of gliomas. We have analyzed the expression of VEGF and its receptors, the related placental growth factor (PlGF) and the endothelial receptors FLT4 and Tie by in situ hybridization in capillary hemangioblastomas and hemangiopericytomas. VEGF mRNA was up-regulated in all of the hemangiopericytomas studied and highly expressed in the stromal cells of hemangioblastomas. In addition, some hemangioblastoma tumor cells expressed high levels of PlGF. Significantly elevated levels of Tie mRNA, Tie protein, VEGFR-1, and VEGFR-2 but not FLT4 mRNAs were observed in the endothelia of both tumor types. In hemangioblastomas, however, the receptors were also highly expressed by a subpopulation of stromal cells. Consistent results were obtained for a human hemangioblastoma cell line in culture. Up-regulation of the endothelial growth factors and receptors may result in autocrine or paracrine stimulation of endothelial cells and their precursors involved in the genesis of these two vascular tumors. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:8774132

  10. Therapeutic Targeting of Fibroblast Growth Factor Receptors in Gastric Cancer

    PubMed Central

    Fujimori, Yoshitaka; Otsuki, Sho; Sato, Yuya; Nakagawa, Masatoshi

    2015-01-01

    Chemotherapy has become the global standard treatment for patients with metastatic or unresectable gastric cancer (GC), although outcomes remain unfavorable. Many molecular-targeted therapies inhibiting signaling pathways of various tyrosine kinase receptors have been developed, and monoclonal antibodies targeting human epidermal growth factor receptor 2 (HER2) have become standard therapy for HER2-positive GC. An inhibitor of vascular endothelial growth factor receptor 2 or MET has also produced promising results in patients with GC. Fibroblast growth factor receptors (FGFR) play key roles in tumor growth via activated signaling pathways in GC. Genomic amplification of FGFR2 leads to the aberrant activation found in GC tumors and is related to survival in patients with GC. This review discusses the clinical relevance of FGFR in GC and examines FGFR as a potential therapeutic target in patients with GC. Preclinical studies in animal models suggest that multitargeted tyrosine kinase inhibitors (TKIs), including FGFR inhibitor, suppress tumor cell proliferation and delay tumor progression. Several TKIs are now being evaluated in clinical trials as treatment for metastatic or unresectable GC harboring FGFR2 amplification. PMID:26000013

  11. 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

  12. FGF19 functions as autocrine growth factor for hepatoblastoma.

    PubMed

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

    2016-03-01

    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.

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

    SciTech Connect

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

    1991-01-01

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

  14. Thrombopoietin is a growth factor for rat hepatic progenitors.

    PubMed

    Schmelzer, Eva; Deiwick, Andrea; Bruns, Helge; Fiegel, Henning C; Bader, Augustinus

    2008-03-01

    The liver is the primary site of hematopoiesis during fetal development; it has been shown that thrombopoietin (TPO) produced by the liver during fetal development is a major regulator of megakaryocytopoiesis. As maximum liver growth and hematopoiesis occur simultaneously, we hypothesized that TPO may act as a growth factor for hepatic progenitors. Therefore, the influence of TPO on the proliferation of fetal hepatic progenitors in vitro compared with that of adult hepatocytes was analyzed. The expression of the TPO receptor, c-mpl, was investigated in fetal and adult liver. Cell proliferation was measured by bromodeoxyuridine incorporation and total cell counts. TPO and c-mpl gene expression was investigated by reverse transcription polymerase chain reaction. The cell surface expression of c-mpl was analyzed in fetal and adult human liver by immunohistochemistry. Hepatic progenitors of fetal and adult liver but not hepatocytes expressed the TPO receptor, c-mpl, on the cell surface. Fetal hepatic progenitors expressed mRNA for TPO and its receptor. TPO stimulated cell proliferation and increased cell numbers of cultured rat fetal hepatic progenitors but not adult hepatocytes. We conclude that TPO acts in addition to its known role in megakaryocytopoiesis as a growth factor for hepatic progenitors but not hepatocytes in vitro; thus, TPO represents a growth factor for hepatic progenitors during fetal liver development.

  15. Very-high-growth-factor Planar Ablative Rayleigh Taylor Experiments

    SciTech Connect

    Bradley, D K; Braun, D G; Glendinning, S G; Edwards, M J; Milovich, J L; Sorce, C M; Collins, G W; Haan, S W; Page, R H

    2006-10-30

    The Rayleigh-Taylor (RT) instability is an important factor in bounding the performance envelope of ignition targets. This paper describes an experiment for ablative RT instability that for the first time achieves growth factors close to those expected to occur in ignition targets at the National Ignition Facility (NIF). The large growth allows small seed perturbations to be detected and can be used to place an upper bound on perturbation growth at the ablation front resulting from microstructure in the preferred Be ablator. The experiments were performed on the Omega laser using a halfraum 1.2 mm long by 2 mm diameter with a 75% laser entrance hole. The halfraum was filled with {approx} 1 atm of neopentane to delay gold plasma from closing the diagnostic line of sight down the axis of the halfraum. The ablator was mounted at the base of the halfraum, and was accelerated by a two stepped X-ray pulse consisting of an early time section {approx} 100 eV to emulate the NIF foot followed by an approximately constant {approx} 150 eV drive sustained over an additional 5-7ns. It is this long pulse duration and late time observation that distinguishes the present work from previous experiments, and is responsible for the large growth that is achieved. The growth of a 2D sinusoidal perturbation machined on the drive side of the ablator was measured using face-on radiography. The diagnostic view remained open until {approx} 11 ns with maximum growth factors measured to be {approx} 200. The trajectory of the ablator was measured using streaked backlit radiography. The design and analysis of the experiments is described, and implications for experiments on ignition target ablators are discussed.

  16. Placental phenotype and the insulin-like growth factors: resource allocation to fetal growth.

    PubMed

    Sferruzzi-Perri, Amanda N; Sandovici, Ionel; Constancia, Miguel; Fowden, Abigail L

    2017-03-24

    The placenta is the main determinant of fetal growth and development in utero. It supplies all the nutrients and oxygen required for fetal growth and secretes hormones that facilitate maternal allocation of nutrients to the fetus. Furthermore, the placenta responds to nutritional and metabolic signals in the mother by altering its structural and functional phenotype which can lead to changes in maternal resource allocation to the fetus. The molecular mechanisms by which the placenta senses and responds to environmental cues are poorly understood. This review discusses the role of the insulin-like growth factors (IGFs) in controlling placental resource allocation to fetal growth, particularly in response to adverse gestational environments. In particular, it assesses the impact of the IGFs and their signalling machinery on placental morphogenesis, substrate transport and hormone secretion, primarily in the laboratory species, although it draws on data from human and other species where relevant. It also considers the role of the IGFs as environmental signals in linking resource availability, to fetal growth through changes in the morphological and functional phenotype of the placenta. As altered fetal growth is associated with increased perinatal morbidity and mortality and a greater risk of developing adult-onset diseases in later life, understanding the role of IGFs during pregnancy in regulating placental resource allocation to fetal growth is important for identifying the mechanisms underlying the developmental programming of offspring phenotype by suboptimal intrauterine growth. This article is protected by copyright. All rights reserved.

  17. Blocking Fibroblast Growth Factor Receptor Signaling Inhibits Tumor Growth, Lymphangiogenesis, and Metastasis

    PubMed Central

    Larrieu-Lahargue, Frédéric; Welm, Alana L.; Bouchecareilh, Marion; Alitalo, Kari; Li, Dean Y.; Bikfalvi, Andreas; Auguste, Patrick

    2012-01-01

    Fibroblast Growth Factor receptor (FGFR) activity plays crucial roles in tumor growth and patient survival. However, FGF (Fibroblast Growth Factor) signaling as a target for cancer therapy has been under-investigated compared to other receptor tyrosine kinases. Here, we studied the effect of FGFR signaling inhibition on tumor growth, metastasis and lymphangiogenesis by expressing a dominant negative FGFR (FGFR-2DN) in an orthotopic mouse mammary 66c14 carcinoma model. We show that FGFR-2DN-expressing 66c14 cells proliferate in vitro slower than controls. 66c14 tumor outgrowth and lung metastatic foci are reduced in mice implanted with FGFR-2DN-expressing cells, which also exhibited better overall survival. We found 66c14 cells in the lumen of tumor lymphatic vessels and in lymph nodes. FGFR-2DN-expressing tumors exhibited a decrease in VEGFR-3 (Vascular Endothelial Growth Factor Receptor-3) or podoplanin-positive lymphatic vessels, an increase in isolated intratumoral lymphatic endothelial cells and a reduction in VEGF-C (Vascular Endothelial Growth Factor-C) mRNA expression. FGFs may act in an autocrine manner as the inhibition of FGFR signaling in tumor cells suppresses VEGF-C expression in a COX-2 (cyclooxygenase-2) or HIF1-α (hypoxia-inducible factor-1 α) independent manner. FGFs may also act in a paracrine manner on tumor lymphatics by inducing expression of pro-lymphangiogenic molecules such as VEGFR-3, integrin α9, prox1 and netrin-1. Finally, in vitro lymphangiogenesis is impeded in the presence of FGFR-2DN 66c14 cells. These data confirm that both FGF and VEGF signaling are necessary for the maintenance of vascular morphogenesis and provide evidence that targeting FGFR signaling may be an interesting approach to inhibit tumor lymphangiogenesis and metastatic spread. PMID:22761819

  18. Epidermal Growth Factor-Like Growth Factors Prevent Apoptosis of Alcohol-Exposed Human Placental Cytotrophoblast Cells1

    PubMed Central

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

    2007-01-01

    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. PMID:17392498

  19. Epidermal growth factor and hepatocyte growth factor receptors collaborate to induce multiple biological responses in bovine mammary epithelial cells.

    PubMed

    Accornero, P; Martignani, E; Miretti, S; Starvaggi Cucuzza, L; Baratta, M

    2009-08-01

    The aim of this work was to explore whether epidermal growth factor (EGF) and hepatocyte growth factor (HGF) could increase the biological responses of a mammary epithelial cell line of bovine origin when added simultaneously. We also investigated a possible molecular mechanism underlying this cooperation. The development of mammary gland requires several circulating and locally produced hormones. Hepatocyte growth factor and its tyrosine kinase receptor, mesenchymal-epithelial transition factor (MET), are expressed and temporally regulated during mammary development and differentiation. Epidermal growth factor receptor and its ligands have also been implicated in the growth and morphogenesis of the mammary epithelium. Both EGF and HGF seem to exert a morphogenic program in this tissue; therefore, we hypothesized that these cytokines could act cooperatively in bovine mammary epithelial cells. We have already shown that the bovine BME-UV cell line, a nontumorigenic mammary epithelial line, expresses both MET and EGF receptor. Simultaneous treatment with HGF and EGF elicited an increase in proliferation, dispersion, degradation of extracellular matrix, and motility. Following EGF treatment, BME-UV mammary cells exhibited an increase in MET expression at both the mRNA and protein levels. Long-term treatment of BME-UV cells with HGF and EGF together increased the level of activation of the extracellular signal-regulated kinase 1/2 and protein kinase B signaling pathways when compared with HGF or EGF alone. These data outline a possible cooperative role of the EGF and HGF pathways and indicate that cross-talk between their respective receptors may modulate mammary gland development in the cow.

  20. Growth factor choice is critical for successful functionalization of nanoparticles

    PubMed Central

    Pinkernelle, Josephine; Raffa, Vittoria; Calatayud, Maria P.; Goya, Gerado F.; Riggio, Cristina; Keilhoff, Gerburg

    2015-01-01

    Nanoparticles (NPs) show new characteristics compared to the corresponding bulk material. These nanoscale properties make them interesting for various applications in biomedicine and life sciences. One field of application is the use of magnetic NPs to support regeneration in the nervous system. Drug delivery requires a functionalization of NPs with bio-functional molecules. In our study, we functionalized self-made PEI-coated iron oxide NPs with nerve growth factor (NGF) and glial cell-line derived neurotrophic factor (GDNF). Next, we tested the bio-functionality of NGF in a rat pheochromocytoma cell line (PC12) and the bio-functionality of GDNF in an organotypic spinal cord culture. Covalent binding of NGF to PEI-NPs impaired bio-functionality of NGF, but non-covalent approach differentiated PC12 cells reliably. Non-covalent binding of GDNF showed a satisfying bio-functionality of GDNF:PEI-NPs, but turned out to be unstable in conjugation to the PEI-NPs. Taken together, our study showed the importance of assessing bio-functionality and binding stability of functionalized growth factors using proper biological models. It also shows that successful functionalization of magnetic NPs with growth factors is dependent on the used binding chemistry and that it is hardly predictable. For use as therapeutics, functionalization strategies have to be reproducible and future studies are needed. PMID:26388717

  1. Nerve Growth Factor Potentiates the Neurotoxicity of β Amyloid

    NASA Astrophysics Data System (ADS)

    Yankner, Bruce A.; Caceres, Alfredo; Duffy, Lawrence K.

    1990-11-01

    The role of growth factors in the pathogenesis of Alzheimer disease is unknown. The β-amyloid protein accumulates abnormally in the brain in Alzheimer disease and is neurotoxic to differentiated hippocampal neurons in culture. Nerve growth factor (NGF) increased the neurotoxic potency of a β-amyloid polypeptide by a factor of ≈100,000, which resulted in a reduction of the β-amyloid neurotoxic EC50 from 0.1 μM to 1 pM. This potentiating effect of NGF was reversed by a monoclonal antibody against NGF and was not observed for a variety of other neurotrophic growth factors. Exposure of hippocampal neurons to very low concentrations of β amyloid alone resulted in a marked induction of immunoreactive NGF receptors. Addition of NGF with β amyloid resulted in the appearance of neurodegenerative changes in NGF receptor-positive neurons. The early and profound degeneration of hippocampal and basal forebrain cholinergic neurons that occurs in Alzheimer disease may result from a neurotoxic interaction of β amyloid with NGF.

  2. Nutrition, insulin, insulin-like growth factors and cancer.

    PubMed

    Giovannucci, E

    2003-01-01

    The incidence of colon, pancreatic, and kidney cancers, as well as aggressive prostate cancer in men, and breast and endometrial cancer in women is invariably high in Western countries. Nutritional and related factors have been typically implicated. This review presents a model integrating nutrition, insulin and IGF-1 physiology ("bioactive" IGF-1), and carcinogenesis based on the following: (1) insulin and the IGF-1 axis function in an integrated fashion to promote cell growth and survival; (2) chronic exposure to these growth properties enhances carcinogenesis; (3) factors that influence bioactive IGF-1 will affect cancer risk. The model presented here summarizes the data that chronic exposure to high levels of insulin and IGF-1 may mediate many of the risk factors for some cancers that are high in Western populations. This hypothesis may help explain some of the epidemiologic patterns observed for these cancers, both from a cross-national perspective and within populations. Of particular importance is that some of relevant factors are modifiable through nutritional and lifestyle interventions. Out of a variety of perspectives presented, nutritional manipulation through the insulin pathway may be more feasible than attempting to influence total IGF-1 concentrations, which are determined largely by growth hormone. Further study is required to test these conclusions.

  3. Growth hormone, the insulin-like growth factor axis, insulin and cancer risk.

    PubMed

    Clayton, Peter E; Banerjee, Indraneel; Murray, Philip G; Renehan, Andrew G

    2011-01-01

    Growth hormone (GH), insulin-like growth factor (IGF)-I and insulin have potent growth-promoting and anabolic actions. Their potential involvement in tumor promotion and progression has been of concern for several decades. The evidence that GH, IGF-I and insulin can promote and contribute to cancer progression comes from various sources, including transgenic and knockout mouse models and animal and human cell lines derived from cancers. Assessments of the GH-IGF axis in healthy individuals followed up to assess cancer incidence provide direct evidence of this risk; raised IGF-I levels in blood are associated with a slightly increased risk of some cancers. Studies of human diseases characterized by excess growth factor secretion or treated with growth factors have produced reassuring data, with no notable increases in de novo cancers in children treated with GH. Although follow-up for the vast majority of these children does not yet extend beyond young adulthood, a slight increase in cancers in those with long-standing excess GH secretion (as seen in patients with acromegaly) and no overall increase in cancer with insulin treatment, have been observed. Nevertheless, long-term surveillance for cancer incidence in all populations exposed to increased levels of GH is vitally important.

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

    PubMed Central

    AGROGIANNIS, GEORGIOS D.; SIFAKIS, STAVROS; PATSOURIS, EFSTRATIOS S.; KONSTANTINIDOU, ANASTASIA E.

    2014-01-01

    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. PMID:24859417

  5. 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.

  6. 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

  7. Lenvatinib in combination with golvatinib overcomes hepatocyte growth factor pathway-induced resistance to vascular endothelial growth factor receptor inhibitor

    PubMed Central

    Nakagawa, Takayuki; Matsushima, Tomohiro; Kawano, Satoshi; Nakazawa, Youya; Kato, Yu; Adachi, Yusuke; Abe, Takanori; Semba, Taro; Yokoi, Akira; Matsui, Junji; Tsuruoka, Akihiko; Funahashi, Yasuhiro

    2014-01-01

    Vascular endothelial growth factor receptor (VEGFR) inhibitors are approved for the treatment of several tumor types; however, some tumors show intrinsic resistance to VEGFR inhibitors, and some patients develop acquired resistance to these inhibitors. Therefore, a strategy to overcome VEGFR inhibitor resistance is urgently required. Recent reports suggest that activation of the hepatocyte growth factor (HGF) pathway through its cognate receptor, Met, contributes to VEGFR inhibitor resistance. Here, we explored the effect of the HGF/Met signaling pathway and its inhibitors on resistance to lenvatinib, a VEGFR inhibitor. In in vitro experiments, addition of VEGF plus HGF enhanced cell growth and tube formation of HUVECs when compared with stimulation by either factor alone. Lenvatinib potently inhibited the growth of HUVECs induced by VEGF alone, but cells induced by VEGF plus HGF showed lenvatinib resistance. This HGF-induced resistance was cancelled when the Met inhibitor, golvatinib, was added with lenvatinib. Conditioned medium from tumor cells producing high amounts of HGF also conferred resistance to inhibition by lenvatinib. In s.c. xenograft models based on various tumor cell lines with high HGF expression, treatment with lenvatinib alone showed weak antitumor effects, but treatment with lenvatinib plus golvatinib showed synergistic antitumor effects, accompanied by decreased tumor vessel density. These results suggest that HGF from tumor cells confers resistance to tumor endothelial cells against VEGFR inhibitors, and that combination therapy using VEGFR inhibitors with Met inhibitors may be effective for overcoming resistance to VEGFR inhibitors. Further evaluation in clinical trials is warranted. PMID:24689876

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

    PubMed

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

    2015-10-01

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

  9. Lenvatinib in combination with golvatinib overcomes hepatocyte growth factor pathway-induced resistance to vascular endothelial growth factor receptor inhibitor.

    PubMed

    Nakagawa, Takayuki; Matsushima, Tomohiro; Kawano, Satoshi; Nakazawa, Youya; Kato, Yu; Adachi, Yusuke; Abe, Takanori; Semba, Taro; Yokoi, Akira; Matsui, Junji; Tsuruoka, Akihiko; Funahashi, Yasuhiro

    2014-06-01

    Vascular endothelial growth factor receptor (VEGFR) inhibitors are approved for the treatment of several tumor types; however, some tumors show intrinsic resistance to VEGFR inhibitors, and some patients develop acquired resistance to these inhibitors. Therefore, a strategy to overcome VEGFR inhibitor resistance is urgently required. Recent reports suggest that activation of the hepatocyte growth factor (HGF) pathway through its cognate receptor, Met, contributes to VEGFR inhibitor resistance. Here, we explored the effect of the HGF/Met signaling pathway and its inhibitors on resistance to lenvatinib, a VEGFR inhibitor. In in vitro experiments, addition of VEGF plus HGF enhanced cell growth and tube formation of HUVECs when compared with stimulation by either factor alone. Lenvatinib potently inhibited the growth of HUVECs induced by VEGF alone, but cells induced by VEGF plus HGF showed lenvatinib resistance. This HGF-induced resistance was cancelled when the Met inhibitor, golvatinib, was added with lenvatinib. Conditioned medium from tumor cells producing high amounts of HGF also conferred resistance to inhibition by lenvatinib. In s.c. xenograft models based on various tumor cell lines with high HGF expression, treatment with lenvatinib alone showed weak antitumor effects, but treatment with lenvatinib plus golvatinib showed synergistic antitumor effects, accompanied by decreased tumor vessel density. These results suggest that HGF from tumor cells confers resistance to tumor endothelial cells against VEGFR inhibitors, and that combination therapy using VEGFR inhibitors with Met inhibitors may be effective for overcoming resistance to VEGFR inhibitors. Further evaluation in clinical trials is warranted.

  10. Growth

    Treesearch

    John R. Jones; George A. Schier

    1985-01-01

    This chapter considers aspen growth as a process, and discusses some characteristics of the growth and development of trees and stands. For the most part, factors affecting growth are discussed elsewhere, particularly in the GENETICS AND VARIATION chapter and in chapters in PART 11. ECOLOGY. Aspen growth as it relates to wood production is examined in the WOOD RESOURCE...

  11. Enhanced Growth of amniotic fluid cells in presence of fibroblast growth factor.

    PubMed

    Porreco, R P; Bradshaw, C; Sarkar, S; Jones, O W

    1980-01-01

    A shorter period of time between amniocentesis and cytogenetic diagnosis is of considerable clinical usefulness. Fibroblast growth factor (FGF), a potent mitogen for cells of mesodermal origin, was used to enhance the growth rate of primary cultures of amniotic fluid-derived cells. At the initial harvest and at 5 scored metaphases, culture dishes incubated with FGF showed a 9-day advantage as a group when compared with their untreated, paired controls. In addition, less variability was encountered in the growth time of the FGF-treated dishes; 97% of these treated dishes were harvested initially between 10 and 20 days, while only 48% of the control dishes were harvested initially during this time period. Success was also noted in the recovery of failing cultures. The addition of FGF to the standard enriched medium used in amniotic fluid cell cultures has shortened the processing time and provided a more uniform growth rate in the majority of cultures studied.

  12. Growth factors as mediators of exercise actions on the brain.

    PubMed

    Llorens-Martín, M; Torres-Alemán, I; Trejo, José L

    2008-01-01

    Physical exercise has long been recognized as highly beneficial for brain and body health. The molecular mechanisms responsible for translation of exercise stimuli in the brain have claimed attention due to mounting evidence for the neuroprotective actions of the exercise and its positive effects in preventing both ageing and neurodegenerative disease. These molecular mediators are currently under investigation with new tools able to yield deep insights into the neurobiology of exercise. In the present work we focus on the evidence pertaining to the mediation of exercise effects by insulin-like growth factor 1 (IGF1), as recent reports suggest that this growth factor shows brain area-specific, temporal rank-sensitive, and behavioural task-dependent features in response to exercise.

  13. Purification of human platelet-derived growth factor.

    PubMed Central

    Antoniades, H N; Scher, C D; Stiles, C D

    1979-01-01

    Human platelets contain a polypeptide growth factor that stimulates the proliferation of connective tissue cells. Purification of this platelet-derived growth factor (PDGF) was accomplished by heat (100 degrees C) treatment of washed platelets and subsequent ion-exchange chromatography, gel filtration in 1 M acetic acid, isoelectric focusing, and preparative sodium dodecyl sulfate/polyacrylamide gel electrophoresis. PDGF has an isoelectric point of 9.8 and a molecular weight ranging from 13,000 to 16,000 as judged by gel filtration in 1 M acetic acid or analytical sodium dodecyl sulfate gel electrophoresis under reducing conditions. The specific activity of the purified PDGF is 20 million times greater than that found in unfractionated human serum. Purified PDGF stimulates replicative DNA synthesis and cell proliferation in quiescent density-arrested cultures of BALB/c 3T3 cells at concentrations of 1 ng/ml (0.1 nM). Images PMID:287022

  14. 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.

  15. Epidermal growth factor receptor tyrosine kinase inhibitors as anticancer agents.

    PubMed

    Ciardiello, F

    2000-01-01

    The epidermal growth factor receptor (EGFR)-driven autocrine growth pathway has been implicated in the development and progression of the majority of the most common human epithelial cancers, making the blockade of this growth pathway a promising anticancer therapeutic strategy. Different approaches have been developed to block EGFR activation and/or function in cancer cells. In the past 15 years, various anti-EGFR blocking monoclonal antibodies (MAb), recombinant proteins containing transforming growth factor-alpha (TGFalpha) or EGF fused to toxins, and tyrosine kinase inhibitors (TKIs) have been generated and their biological and potentially therapeutic properties characterised. One of these agents, MAb IMC-C225, a chimeric human-mouse IgG1 MAb, is the first anti-EGFR agent to enter phase II to III clinical trials in patients with cancer. Several small compounds that block the ligand-induced activation of the EGFR tyrosine kinase have been developed. Among these EGFR-TKIs, various quinazoline-derived agents have been synthesised and have shown promising activity as anticancer agents in preclinical models. ZD1839 ('Iressa'), an anilinoquinazoline, is an orally active, selective EGFR-TKI which is currently under clinical evaluation in phase II to III clinical trials in patients with cancer. Preclinical data for ZD1839 strongly support the possibility of potentiating the antitumour activity of conventional chemotherapy with agents that selectively block the EGFR.

  16. Endocrine fibroblast growth factor FGF19 promotes prostate cancer progression.

    PubMed

    Feng, Shu; Dakhova, Olga; Creighton, Chad J; Ittmann, Michael

    2013-04-15

    Prostate cancer is the most common visceral malignancy and the second leading cause of cancer deaths in US men. There is broad evidence that fibroblast growth factor (FGF) receptors are important in prostate cancer initiation and progression, but the contribution of particular FGFs in this disease is not fully understood. The FGF family members FGF19, FGF21, and FGF23 comprise a distinct subfamily that circulate in serum and act in an endocrine manner. These endocrine FGFs require α-Klotho (KL) and/or β-Klotho (KLB), two related single-pass transmembrane proteins restricted in their tissue distribution, to act as coreceptors along with classic FGF receptors (FGFR) to mediate potent biologic activity. Here we show that FGF19 is expressed in primary and metastatic prostate cancer tissues, where it functions as an autocrine growth factor. Exogenous FGF19 promoted the growth, invasion, adhesion, and colony formation of prostate cancer cells at low ligand concentrations. FGF19 silencing in prostate cancer cells expressing autocrine FGF19 decreased invasion and proliferation in vitro and tumor growth in vivo. Consistent with these observations, KL and/or KLB were expressed in prostate cancer cells in vitro and in vivo, raising the possibility that additional endocrine FGFs may also exert biologic effects in prostate cancer. Our findings support the concept that therapies targeting FGFR signaling may have efficacy in prostate cancer and highlight FGF19 as a relevant endocrine FGF in this setting.

  17. Insulin-like growth factor- I and factors affecting it in thalassemia major

    PubMed Central

    Soliman, Ashraf T.; Sanctis, Vincenzo De; Elalaily, Rania; Yassin, Mohamed

    2015-01-01

    Despite improvement of blood transfusion regimens and iron chelation therapy growth and maturational delay, cardiomyopathy, endocrinopathies and osteoporosis still occur in good number of thalassemic patients. Decreased IGF-1 secretion occurs in the majority of the thalassemic patients particularly those with growth and pubertal delay. Many factors contribute to this decreased synthesis of IGF-I including disturbed growth hormone (GH) - insulin-like growth factor - I (IGF-I) axis. The possible factors contributing to low IGF-I synthesis in thalassemia and the possible interaction between low IGF-I secretion and the occurrence of these complications is discussed in this mini-review. Improvement of IGF-I secretion in thalassemic patients should be intended to improve linear growth and bone mineral accretion in thalassemic patients. This can be attained through adequate correction of anemia and proper chelation, nutritional supplementation (increasing caloric intake), correction of vitamin D and zinc deficiencies, induction of puberty and correction of hypogonadism at the proper time and treating GH deficiency. This review paper provides a summary of the current state of knowledge regarding IGF-I and factors affecting it in patients with thalassaemia major (TM). Search on PubMed and reference lists of articles with the term ‘IGF-I, GH, growth, thalassemia, thyroxine, anemia, vitamin D, and zinc’ was carried out. A hundred and forty-eight articles were found and used in the write up and the data analyzed was included in this report. PMID:25729686

  18. Insulin-like growth factor- I and factors affecting it in thalassemia major.

    PubMed

    Soliman, Ashraf T; De Sanctis, Vincenzo; Elalaily, Rania; Yassin, Mohamed

    2015-01-01

    Despite improvement of blood transfusion regimens and iron chelation therapy growth and maturational delay, cardiomyopathy, endocrinopathies and osteoporosis still occur in good number of thalassemic patients. Decreased IGF-1 secretion occurs in the majority of the thalassemic patients particularly those with growth and pubertal delay. Many factors contribute to this decreased synthesis of IGF-I including disturbed growth hormone (GH) - insulin-like growth factor - I (IGF-I) axis. The possible factors contributing to low IGF-I synthesis in thalassemia and the possible interaction between low IGF-I secretion and the occurrence of these complications is discussed in this mini-review. Improvement of IGF-I secretion in thalassemic patients should be intended to improve linear growth and bone mineral accretion in thalassemic patients. This can be attained through adequate correction of anemia and proper chelation, nutritional supplementation (increasing caloric intake), correction of vitamin D and zinc deficiencies, induction of puberty and correction of hypogonadism at the proper time and treating GH deficiency. This review paper provides a summary of the current state of knowledge regarding IGF-I and factors affecting it in patients with thalassaemia major (TM). Search on PubMed and reference lists of articles with the term 'IGF-I, GH, growth, thalassemia, thyroxine, anemia, vitamin D, and zinc' was carried out. A hundred and forty-eight articles were found and used in the write up and the data analyzed was included in this report.

  19. The Role of Growth Hormone and Insulin-Like Growth Factor 1 in Human Breast Cancer Growth in a Mouse Xenograft Model

    DTIC Science & Technology

    1998-10-01

    The purpose of this research is to determine the role of human growth hormone (hGH) and insulin-like growth factor 1(IGF-1) in the development of an...progression of tumor growth in the animal model. In addition, growth hormone may be semi-inhibitory to growth for tumors dependent upon estrogen

  20. The Role of Growth Hormone and Insulin-Like Growth Factor-1 in Human Breast Cancer Growth in a Mouse Xenograft Model

    DTIC Science & Technology

    1999-10-01

    The purpose of this research is to determine the role of human growth hormone (hGH) and insulin-like growth factor 1 (IGF- 1) in the development of...the progression of tumor growth in the animal model. In addition growth hormone may be semi-inhibitory to growth for tumors dependent upon estrogen

  1. Regulation of skeletal muscle growth in fish by the growth hormone--insulin-like growth factor system.

    PubMed

    Fuentes, Eduardo N; Valdés, Juan Antonio; Molina, Alfredo; Björnsson, Björn Thrandur

    2013-10-01

    The growth hormone (GH)-insulin-like growth factor (IGF) system is the key promoter of growth in vertebrates; however, how this system modulates muscle mass in fish is just recently becoming elucidated. In fish, the GH induces muscle growth by modulating the expression of several genes belonging to the myostatin (MSTN), atrophy, GH, and IGF systems as well as myogenic regulatory factors (MRFs). The GH controls the expression of igf1 via Janus kinase 2 (JAK2)/signal transducers and activators of the transcription 5 (STAT5) signaling pathway, but it seems that it is not the major regulator. These mild effects of the GH on igf1 expression in fish muscle seem to be related with the presence of higher contents of truncated GH receptor1 (tGHR1) than full length GHR (flGHR1). IGFs in fish stimulate myogenic cell proliferation, differentiation, and protein synthesis through the MAPK/ERK and PI3K/AKT/TOR signaling pathways, concomitant with abolishing protein degradation and atrophy via the PI3K/AKT/FOXO signaling pathway. Besides these signaling pathways control the expression of several genes belonging to the atrophy and IGF systems. Particularly, IGFs and amino acid control the expression of igf1, thus, suggesting other of alternative signaling pathways regulating the transcription of this growth factor. The possible role of IGF binding proteins (IGFBPs) and the contribution of muscle-derived versus hepatic-produced IGF1 on fish muscle growth is also addressed. Thus, a comprehensive overview on the GH-IGF system regulating fish skeletal muscle growth is presented, as well as perspectives for future research in this field. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. 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.

  3. Nerve Growth Factor: A Focus on Neuroscience and Therapy

    PubMed Central

    Aloe, Luigi; Rocco, Maria Luisa; Omar Balzamino, Bijorn; Micera, Alessandra

    2015-01-01

    Nerve growth factor (NGF) is the firstly discovered and best characterized neurotrophic factor, known to play a critical protective role in the development and survival of sympathetic, sensory and forebrain cholinergic neurons. NGF promotes neuritis outgrowth both in vivo and in vitro and nerve cell recovery after ischemic, surgical or chemical injuries. Recently, the therapeutic property of NGF has been demonstrated on human cutaneous and corneal ulcers, pressure ulcer, glaucoma, maculopathy and retinitis pigmentosa. NGF eye drops administration is well tolerated, with no detectable clinical evidence of systemic or local adverse effects. The aim of this review is to summarize these biological properties and the potential clinical development of NGF. PMID:26411962

  4. Vancouver Experience of Recombinant Human Platelet-Derived Growth Factor.

    PubMed

    Younger, Alistair; Penner, Murray; Montijo, Harvey E

    2016-12-01

    Joint arthrodesis utilizing autogenous bone graft remains the gold standard of treatment in fusion procedures of the foot and ankle. Graft harvest, however, has been associated with increased morbidity to patients as well as increased costs. With this in mind, multiple clinical studies have evaluated the efficacy of recombinant human platelet-derived growth factor (rh-PDGF-BB) with beta-tricalcium phosphate (B-TCP) to augment in foot and ankle arthrodesis with favorable results. These factors have led to the increased use of rh-PDGF-BB with B-TCP in Vancouver with good clinical results. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Methods for studying the platelet-derived growth factor receptor

    SciTech Connect

    Bowen-Pope, D.F.; Ross, R.

    1985-01-01

    Platelet-derived growth factor (PDGF) is a basic 30,000-dalton protein circulating in normal blood sequestered within the platelet alpha granule. Radioiodinated PDGF shows saturable (e.g., 60,000-120,000 receptors per diploid human fibroblast) high affinity binding to culture PDGF-responsive cells. The apparent dissociation constant reported for this binding interaction has varied widely. This paper focuses on factors which affect (/sup 125/I)PGDF binding and on the development of a radioreceptor assay for PDGF.

  6. Purification of human platelet-derived growth factor

    SciTech Connect

    Raines, E.W.; Ross, R.

    1985-01-01

    The paper describes a method for purification of human platelet-derived growth factor (PDGF) from outdated platelet-rich plasma (PRP) using commonly available laboratory reagents and yielding a mitogen purified 800,000-fold over the starting material. (/sup 3/H)thymidine incorporation into DNA of cultured cells responsive to PDGF represents the most readily available method to follow its purification and define the biological activity of a purified preparation. Other assays to quantitate PDGF include radioreceptor assay and radioimmunoassay.

  7. PDGF in gliomas: more than just a growth factor?

    PubMed Central

    Lindberg, Nanna

    2012-01-01

    Platelet-derived growth factor B (PDGF-B) is a growth factor promoting and regulating cell migration, proliferation, and differentiation, involved in both developmental processes and in maintaining tissue homeostasis under strict regulation. What are the implications of prolonged or uncontrolled growth factor signaling in vivo, and when does a growth factor such as PDGF-B become an oncogene? Under experimental conditions, PDGF-B induces proliferation and causes tumor induction. It is not known whether these tumors are strictly a PDGF-B-driven proliferation of cells or associated with secondary genetic events such as acquired mutations or methylation-mediated gene silencing promoting neoplasia. If PDGF-B-driven tumorigenesis was only cellular proliferation, associated changes in gene expression would thus be correlated with proliferation and not associated with secondary events involved in tumorigenesis and neoplastic transformation such as cycle delay, DNA damage response, and cell death. Changes in gene expression might be expected to be reversible, as is PDGF-B-driven proliferation under normal circumstances. Since PDGF signaling is involved in oligodendrocyte progenitor cell differentiation and maintenance, it is likely that PDGF-B stimulates proliferation of a pool of cells with that phenotype, and inhibition of PDGF-B signaling would result in reduced expression of oligodendrocyte-associated genes. More importantly, inhibition of PDGF signaling would be expected to result in reversion of genes induced by PDGF-B accompanied by a decrease in proliferation. However, if PDGF-B-driven tumorigenesis is more than simply a proliferation of cells, inhibition of PDGF signaling may not reverse gene expression or halt proliferation. These fundamental questions concerning PDGF-B as a potential oncogene have not been resolved. PMID:22376240

  8. Cytokines and growth factors cross-link heparan sulfate

    PubMed Central

    Migliorini, Elisa; Thakar, Dhruv; Kühnle, Jens; Sadir, Rabia; Dyer, Douglas P.; Li, Yong; Sun, Changye; Volkman, Brian F.; Handel, Tracy M.; Coche-Guerente, Liliane; Fernig, David G.; Lortat-Jacob, Hugues; Richter, Ralf P.

    2015-01-01

    The glycosaminoglycan heparan sulfate (HS), present at the surface of most cells and ubiquitous in extracellular matrix, binds many soluble extracellular signalling molecules such as chemokines and growth factors, and regulates their transport and effector functions. It is, however, unknown whether upon binding HS these proteins can affect the long-range structure of HS. To test this idea, we interrogated a supramolecular model system, in which HS chains grafted to streptavidin-functionalized oligoethylene glycol monolayers or supported lipid bilayers mimic the HS-rich pericellular or extracellular matrix, with the biophysical techniques quartz crystal microbalance (QCM-D) and fluorescence recovery after photobleaching (FRAP). We were able to control and characterize the supramolecular presentation of HS chains—their local density, orientation, conformation and lateral mobility—and their interaction with proteins. The chemokine CXCL12α (or SDF-1α) rigidified the HS film, and this effect was due to protein-mediated cross-linking of HS chains. Complementary measurements with CXCL12α mutants and the CXCL12γ isoform provided insight into the molecular mechanism underlying cross-linking. Fibroblast growth factor 2 (FGF-2), which has three HS binding sites, was also found to cross-link HS, but FGF-9, which has just one binding site, did not. Based on these data, we propose that the ability to cross-link HS is a generic feature of many cytokines and growth factors, which depends on the architecture of their HS binding sites. The ability to change matrix organization and physico-chemical properties (e.g. permeability and rigidification) implies that the functions of cytokines and growth factors may not simply be confined to the activation of cognate cellular receptors. PMID:26269427

  9. Nerve Growth Factor Effects on the Immune System

    DTIC Science & Technology

    1989-12-19

    growth factor protein, NGF, has been shown to play a physiologic role in the development and regeneration of the peripheral nervous system, acting on...determine the effects of NGF on lymphocytes with an aim to understanding the physiological and developmental role of NGF in the immune system. Our approaches...Thorpe and Perez-Polo, 1987). Although the maximal response of these cells occurs at levels significantly above those considered physiological it is

  10. Fibroblast growth factor signaling during early vertebrate development.

    PubMed

    Böttcher, Ralph T; Niehrs, Christof

    2005-02-01

    Fibroblast growth factors (FGFs) have been implicated in diverse cellular processes including apoptosis, cell survival, chemotaxis, cell adhesion, migration, differentiation, and proliferation. This review presents our current understanding on the roles of FGF signaling, the pathways employed, and its regulation. We focus on FGF signaling during early embryonic processes in vertebrates, such as induction and patterning of the three germ layers as well as its function in the control of morphogenetic movements.

  11. Cytokine and Growth Factor Concentrations in Canine Autologous Conditioned Serum.

    PubMed

    Sawyere, Dominique M; Lanz, Otto I; Dahlgren, Linda A; Barry, Sabrina L; Nichols, Anne C; Werre, Stephen R

    2016-07-01

    To compare cytokine and growth factor concentrations in canine autologous conditioned serum (ACS) to canine plasma. Experimental in vivo study. Client-owned, adult dogs (n=22). Blood collected from 16 medium to large breed dogs was used to produce ACS (Orthokine(®) vet irap 10 syringes) and citrated plasma (control). Canine-specific ELISA assays were run per manufacturers' instructions for interleukin (IL)-10, IL-4, tumor necrosis factor (TNF)-α, insulin-like growth factor (IGF)-1, fibroblast growth factor (FGF)-2, transforming growth factor (TGF)-β1, IL-1β, and interleukin-1 receptor antagonist (IL-1ra). Serum, in addition to plasma and ACS, was collected from an additional 6 dogs for TNF-α, IL-1β, and IL-1ra analysis (total of 22 dogs). Data were analyzed for differences in each cytokine concentration using pairwise comparisons between ACS, plasma, and serum using Wilcoxon signed-rank tests. Significance was set at P<.05. There was a large variability in growth factor and cytokine concentrations in ACS and plasma for individual dogs. There were no significant differences in IL-10, TNF-α, IGF-1, FGF-2, and TGF-β1 concentrations between ACS, plasma, and serum. The IL-1β concentrations in ACS (median, range 46.3 pg/mL, 0-828.8) and IL-4 (0.0 pg/mL, 0-244.1) were significantly higher than plasma (36.6 pg/mL, 0-657.1 and 0.0 pg/mL, 0-0, respectively). The IL-1ra concentration in ACS (median, range 3,458.9 pg/mL, 1,243.1-12,089.0) was significantly higher than plasma (692.3 pg/mL, 422.5-1,475.6). The IL-1ra:IL-1β ratio in ACS was significantly higher than plasma (39.9 vs. 7.2). IL-1ra concentrations in canine ACS were comparable to those published for people and horses and pro-inflammatory cytokines remained low in canine ACS. © Copyright 2016 by The American College of Veterinary Surgeons.

  12. Fibroblast growth factor (FGF) signaling regulates transforming growth factor beta (TGFβ)-dependent smooth muscle cell phenotype modulation

    PubMed Central

    Chen, Pei-Yu; Qin, Lingfeng; Li, Guangxin; Tellides, George; Simons, Michael

    2016-01-01

    Smooth muscle cells (SMCs) in normal blood vessels exist in a highly differentiate state characterized by expression of SMC-specific contractile proteins (“contractile phenotype”). Following blood vessel injury in vivo or when cultured in vitro in the presence of multiple growth factors, SMC undergo a phenotype switch characterized by the loss of contractile markers and appearance of expression of non-muscle proteins (“proliferative phenotype”). While a number of factors have been reported to modulate this process, its regulation remains uncertain. Here we show that induction of SMC FGF signaling inhibits TGFβ signaling and converts contractile SMCs to the proliferative phenotype. Conversely, inhibition of SMC FGF signaling induces TGFβ signaling converting proliferating SMCs to the contractile phenotype, even in the presence of various growth factors in vitro or vascular injury in vivo. The importance of this signaling cross-talk is supported by in vivo data that show that an SMC deletion of a pan-FGF receptor adaptor Frs2α (fibroblast growth factor receptor substrate 2 alpha) in mice profoundly reduces neointima formation and vascular remodelling following carotid artery ligation. These results demonstrate that FGF-TGFβ signaling antagonism is the primary regulator of the SMC phenotype switch. Manipulation of this cross-talk may be an effective strategy for treatment of SMC-proliferation related diseases. PMID:27634335

  13. Synergistic action of fibroblast growth factor-2 and transforming growth factor-beta1 enhances bioprinted human neocartilage formation.

    PubMed

    Cui, Xiaofeng; Breitenkamp, Kurt; Lotz, Martin; D'Lima, Darryl

    2012-09-01

    Bioprinting as a promising but unexplored approach for cartilage tissue engineering has the advantages of high throughput, digital control, and highly accurate placement of cells and biomaterial scaffold to the targeted 3D locations with simultaneous polymerization. This study tested feasibility of using bioprinting for cartilage engineering and examined the influence of cell density, growth, and differentiation factors. Human articular chondrocytes were printed at various densities, stimulated transiently with growth factors and subsequently with chondrogenic factors. Samples were cultured for up to 4 weeks to evaluate cell proliferation and viability, mechanical properties, mass swelling ratio, water content, gene expression, ECM production, DNA content, and histology. Bioprinted samples treated with FGF-2/TGF-β1 had the best chondrogenic properties among all groups apparently due to synergistic stimulation of cell proliferation and chondrogenic phenotype. ECM production per chondrocyte in low cell density was much higher than that in high cell seeding density. This finding was also verified by mechanical testing and histology. In conclusion, cell seeding density that is feasible for bioprinting also appears optimal for human neocartilage formation when combined with appropriate growth and differentiation factors. Copyright © 2012 Wiley Periodicals, Inc.

  14. 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.

  15. Polyethlyene glycol microgels to deliver bioactive nerve growth factor.

    PubMed

    Stukel, Jessica; Thompson, Susan; Simon, Laurent; Willits, Rebecca

    2015-02-01

    Delivery of bioactive molecules is a critical step in fabricating materials for regenerative medicine, yet, this step is particularly challenging in hydrated scaffolds such as hydrogels. Although bulk photocrosslinked poly(ethylene glycol) (PEG) hydrogels have been used for a variety of tissue engineering applications, their capability as drug delivery scaffolds has been limited due to undesirable release profiles and reduction in bioactivity of molecules. To solve these problems, this article presents the fabrication of degradable PEG microgels, which are micron-sized spherical hydrogels, to deliver bioactive nerve growth factor (NGF). NGF release and activity was measured after encapsulation in microgels formed from either 3 kDa or 6 kDa PEG to determine the role of hydrogel mesh size on release. Microgels formed from 6 kDa PEG were statistically larger and had a higher swelling ratio than 3 kDa PEG. The 6 kDa PEG microgels provided a Fickian release with a reduced burst effect and 3 kDa microgels provided anomalous release over ≥20 days. Regardless of molecular weight of PEG, NGF bioactivity was not significantly reduced compared to unprocessed NGF. These results demonstrate that microgels provide easy mechanisms to control the release while retaining the activity of growth factors. As this microgel-based delivery system can be injected at the site of nerve injury to promote nerve repair, the potential to deliver active growth factors in a controlled manner may reduce healing time for neural tissue engineering applications.

  16. UV activates growth factor receptors via reactive oxygen intermediates

    PubMed Central

    1996-01-01

    Exposure of mammalian cells to UV irradiation induces rapid and transient expression of early growth response-1 gene (Egr-1) encoding a transcription factor that plays a role in cell survival. These signals from the irradiated cell surface are likely to involve more than one pathway, and we show here that an essential pathway involves activation of several growth factor receptors by reactive oxygen intermediates (ROI). UVC irradiation causes the tyrosine phosphorylation of EGF receptor (EGFR) in mouse NIH 3T3 fibroblasts and HC11 mouse mammary cells. EGFR activation by irradiation of cells is abrogated by suramin, by antioxidants, and by the presence of a dominant negative EGFR. UV induces the formation of complexes between activated EGFR and SOS, Grb2, PLC gamma, and SHC that can be precipitated with antibodies to EGFR. The activation of EGFR by UV is mimicked by H2O2, suggesting that ROI may function upstream of EGFR activation. Our observations support the hypothesis that ROI and growth factor receptors operate in the early steps of the UV signal that lead to the enhanced expression and activity of Egr-1. PMID:8601609

  17. 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

  18. Astrocyte growth is regulated by neuropeptides through Tis 8 and basic fibroblast growth factor.

    PubMed Central

    Hu, R M; Levin, E R

    1994-01-01

    The important intracellular mechanisms of astrocyte growth are not well defined. Using an inhibitor of astrocyte proliferation, atrial natriuretic peptide (ANP), and the glial mitogen endothelin (ET-3), we sought a common pathway for growth regulation in these neural cells. In cultured fetal rat diencephalic astrocytes, ANP selectively and rapidly inhibited the Tis 8 immediate early gene and protein. After 4 h, ANP selectively inhibited the basic fibroblast growth factor (bFGF) gene and protein. ET-3 significantly stimulated both Tis 8 and bFGF mRNAs and protein, but also stimulated several other immediate early and growth factor/receptor genes. An antisense oligonucleotide to Tis 8 strongly prevented ET-stimulated thymidine incorporation, while the inhibitory action of ANP was enhanced. The Tis 8 antisense oligonucleotide also significantly reversed ET-stimulated bFGF transcription and enhanced the bFGF inhibition caused by ANP. In addition, an antisense oligonucleotide to bFGF significantly reversed the ET-stimulated thymidine incorporation and enhanced the ANP inhibition of DNA synthesis. The sequential modulation of Tis 8, followed by bFGF, provides a novel mechanism for both positive and negative regulation of astrocyte growth by endogenous neuropeptides. Images PMID:8163680

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

    SciTech Connect

    Lokeshwar, V.B.

    1989-01-01

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

  20. 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).

  1. Processing, secretion, and biological properties of a novel growth factor of the fibroblast growth factor family with oncogenic potential

    SciTech Connect

    Delli-Bovi, P.; Curatola, A.M.; Newman, K.M.; Sato, Y.; Moscatelli, D.; Hewick, R.M.; Rifkin, D.B.; Basilico, C.

    1988-07-01

    The authors recently reported that the protein encoded in a novel human oncogene isolated from Kaposi sarcoma DNA was a growth factor with significant homology to basic and acidic fibroblast growth factors (FGFs). To study the properties of this growth factor (referred to as K-FGF) and the mechanism by which the K-fgf oncogene transforms cells, the authors have studied the production and processing of K-FGF in COS-1 cells transfected with a plasmid encoding the K-fgf cDNA. The results show that, unkike basic and acidic FGFs, the K-FGF protein is cleaved after a single peptide, glycosylated, and efficiently secreted as a mature protein of 176 or 175 amino acids. Inhibition of glycosylation impaired secretion, and the stability of the secreted K-FGF was greatly enhanced by the presence of heparin in the cultured medium. They have used the conditioned medium from transfected COS-1 cells to test the K-FGF biological activity. Similar to basic FGF, the K-FGF protein was mitogenic for fibroblasts and endothelial cells and induced the growth of NIH 3T3 mouse cells in serum-free medium. Accordingly, K-fgf-transformed NIH 3T3 cells grew in serum-free medium consistent with an autorcrine mechanism of growth. The authors have also expressed the protein encoded in the K-fgf protooncogene in COS-1 cells, and it was indistinguishable in its molecular weight, glycosylation, secretion, and biological activity from K-FGF. Taken together, these results suggest that the mechanism of activation of this oncogene is due to overexpression rather than to mutations in the coding sequences.

  2. Growth rate and associated factors in small abdominal aortic aneurysms.

    PubMed

    Vega de Céniga, M; Gómez, R; Estallo, L; Rodríguez, L; Baquer, M; Barba, A

    2006-03-01

    To study the growth rate and factors influencing progression of small infrarenal abdominal aortic aneurysms (AAA). Observational, longitudinal, prospective study. We followed patients with AAA <5 cm in diameter in two groups. Group I (AAA 3-3.9 cm, n = 246) underwent annual ultrasound scans. Group II (AAA 4-4.9 cm, n = 106) underwent 6-monthly CT scans. We included 352 patients (333 men and 19 women) followed for a mean of 55.2+/-37.4 months (6.3-199.8). The mean growth rate was significantly greater in group II (4.72+/-5.93 vs. 2.07+/-3.23 mm/year; p<0.0001). Group II had a greater percentage of patients with rapid aneurysm expansion (>4 mm/year) (36.8 vs. 13.8%; p<0.0001). The classical cardiovascular risk factors did not influence the AAA growth rate in group I. Chronic limb ischemia was associated with slower expansion (< or = 4 mm/year) (OR 0.47; CI 95% 0.22-0.99; p = 0.045). Diabetic patients in group II had a significantly smaller mean AAA growth rate than non-diabetics (1.69+/-3.51 vs. 5.22+/-6.11 mm/year; p = 0.032). The expansion rate of small AAA increases with the AAA size. AAA with a diameter of 3-3.9 cm expand slowly, and they are very unlikely to require surgical repair in 5 years. Many 4-4.9 cm AAA can be expected to reach a surgical size in the first 2 years of follow-up. Chronic limb ischemia and diabetes are associated with reduced aneurysm growth rates.

  3. 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.

  4. 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.

  5. Vascular endothelial growth factor is a potential tumour angiogenesis factor in human gliomas in vivo

    NASA Astrophysics Data System (ADS)

    Plate, Karl H.; Breier, Georg; Weich, Herbert A.; Risau, Werner

    1992-10-01

    CLINICAL and experimental studies suggest that angiogenesis is a prerequisite for solid tumour growth1,2. Several growth factors with mitogenic or chemotactic activity for endothelial cells in vitro have been described, but it is not known whether these mediate tumour vascularization in vivo3,4. Glioblastoma, the most common and most malignant brain tumour in humans, is distinguished from astrocytoma by the presence of necroses and vascular prolifer-ations5'6. Here we show that expression of an endothelial cell-specific mitogen, vascular endothelial growth factor (VEGF), is induced in astrocytoma cells but is dramatically upregulated in two apparently different subsets of glioblastoma cells. The high-affinity tyrosine kinase receptor for VEGF, flt, although not expressed in normal brain endothelium, is upregulated in tumour endothelial cells in vivo. These observations strongly support the concept that tumour angiogenesis is regulated by paracrine mechanisms and identify VEGF as a potential tumour angiogenesis factor in vivo.

  6. Placental growth factor is a survival factor for tumor endothelial cells and macrophages.

    PubMed

    Adini, Avner; Kornaga, Tad; Firoozbakht, Farshid; Benjamin, Laura E

    2002-05-15

    The vascular endothelial growth factor (VEGF)-related factor, placental growth factor (PlGF),has been shown recently to play an important role in pathological VEGF-driven angiogenesis. In this study, we examine the effects of mPlGF/PlGF-2 overexpression in tumors grown from glioma cells containing a tetracycline-regulated mPlGF cDNA. Overexpression of mPlGF leads to increased tumor growth and vascular survival. When tetracycline is used to abruptly withdraw mPlGF overexpression, we see increased apoptosis in both vascular cells and macrophages. In addition, PlGF-2 induces survival gene expression and inhibits apoptosis in vitro. Thus, we propose that PlGF-2 contributes to tumor angiogenesis by providing increased survival function to endothelial cells and macrophages.

  7. [Epidermal growth factor during pregnancy- a predictor of fetal growth retardation?].

    PubMed

    Huter, O; Kölle, D; Brezinka, C; Artner-Dworzak, E

    1998-01-01

    Epidermal growth factor (EGF) in urine was measured at 4-week intervals in 83 women referred for suspected intrauterine growth retardation (IUGR); 138 women with normal singleton pregnancies and newborns of normal weight served as controls. Of the 83 women, 30 delivered babies with weight below the 10th percentile after week 37. During pregnancy these women had shown significantly lower EGF levels than women who delivered normal-weight babies. However, due to the wide distribution of individual EGF data, no clear clinical cut-off point between normal and IUGR values could be established.

  8. Regulation of plant growth and development by the GROWTH-REGULATING FACTOR and GRF-INTERACTING FACTOR duo.

    PubMed

    Hoe Kim, Jeong; Tsukaya, Hirokazu

    2015-10-01

    Transcription factors are key regulators of gene expression and play pivotal roles in all aspects of living organisms. Therefore, identification and functional characterization of transcription factors is a prerequisite step toward understanding life. This article reviews molecular and biological functions of the two transcription regulator families, GROWTH-REGULATING FACTOR (GRF) and GRF-INTERACTING FACTOR (GIF), which have only recently been recognized. A myriad of experimental evidence clearly illustrates that GRF and GIF are bona fide partner proteins and form a plant-specific transcriptional complex. One of the most conspicuous outcomes from this research field is that the GRF-GIF duo endows the primordial cells of vegetative and reproductive organs with a meristematic specification state, guaranteeing the supply of cells for organogenesis and successful reproduction. It has recently been shown that GIF1 proteins, also known as ANGUSTIFOLIA3, recruit chromatin remodelling complexes to target genes, and that AtGRF expression is directly activated by the floral identity factors, APETALA1 and SEPALLATA3, providing an important insight into understanding of the action of GRF-GIF. Moreover, GRF genes are extensively subjected to post-transcriptional control by microRNA396, revealing the presence of a complex regulatory circuit in regulation of plant growth and development by the GRF-GIF duo. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  9. Heparin-binding epidermal growth factor-like growth factor/diphtheria toxin receptor expression by acute myeloid leukemia cells.

    PubMed

    Vinante, F; Rigo, A; Papini, E; Cassatella, M A; Pizzolo, G

    1999-03-01

    Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is an EGF family member expressed by numerous cell types that binds to EGF receptor 1 (HER-1) or 4 (HER-4) inducing mitogenic and/or chemotactic activities. Membrane-bound HB-EGF retains growth activity and adhesion capabilities and the unique property of being the receptor for diphtheria toxin (DT). The interest in studying HB-EGF in acute leukemia stems from these mitogenic, chemotactic, and receptor functions. We analyzed the expression of HB-EGF in L428, Raji, Jurkat, Karpas 299, L540, 2C8, HL-60, U937, THP-1, ML-3, and K562 cell lines and in primary blasts from 12 acute myeloid leukemia (AML) cases, by reverse-transcriptase polymerase chain reaction (RT-PCR) and Northern blot and by the evaluation of sensitivity to DT. The release of functional HB-EGF was assessed by evaluation of its proliferative effects on the HB-EGF-sensitive Balb/c 3T3 cell line. HB-EGF was expressed by all myeloid and T, but not B (L428, Raji), lymphoid cell lines tested, as well as by the majority (8 of 12) of ex vivo AML blasts. Cell lines (except for the K562 cell line) and AML blasts expressing HB-EGF mRNA underwent apoptotic death following exposure to DT, thus demonstrating the presence of the HB-EGF molecule on their membrane. Leukemic cells also released a fully functional HB-EGF molecule that was mitogenic for the Balb/c 3T3 cell line. Factors relevant to the biology of leukemic growth, such as tumor necrosis factor-alpha (TNF-alpha), 1alpha,25-(OH)2D3, and especially all-trans retinoic acid (ATRA), upregulated HB-EGF mRNA in HL-60 or ML-3 cells. Granulocyte-macrophage colony-stimulating factor (GM-CSF) induced HB-EGF mRNA and acquisition of sensitivity to DT in one previously HB-EGF-negative leukemia case. Moreover, the U937 and Karpas 299 cell lines expressed HER-4 mRNA. This work shows that HB-EGF is a growth factor produced by primary leukemic cells and regulated by ATRA, 1alpha, 25-(OH)2D3, and GM-CSF.

  10. Vascular endothelial growth factor mediates corneal nerve repair.

    PubMed

    Yu, Charles Q; Zhang, Min; Matis, Krisztina I; Kim, Charles; Rosenblatt, Mark I

    2008-09-01

    To examine the expression of vascular endothelial growth factor (VEGF) and its receptors in the cornea and the trigeminal ganglion and to characterize the role of VEGF in mediating corneal nerve repair. Regeneration of the corneal subbasal nerve plexus after epithelial debridement was measured. The expression of VEGF and its receptors was examined in the trigeminal ganglia and in the cornea by RT-PCR, immunohistochemistry, and Western blotting. VEGF-mediated nerve growth was measured in a trigeminal ganglia explant assay. Anti-VEGF neutralizing antibody was used to examine the VEGF-dependent growth of neurons in vitro and regeneration of the corneal nerves in vivo. After two distinct patterns of nerve regeneration, the subbasal nerves recovered to 65% of the preinjury density after 28 days. RT-PCR demonstrated gene expression of VEGF and VEGF receptors in the trigeminal ganglia. Immunohistochemistry showed staining for VEGF and its receptors in the trigeminal ganglia and for VEGFR1, VEGFR2, and neuropilin (NRP)-1 in the cornea. Western blot confirmed these results. In vitro, VEGF promoted the growth of explanted trigeminal ganglia by 91%. Blockage of VEGF signaling with anti-VEGF antibody reduced the growth of cultured neurons by 17% and the regeneration of subbasal neurons by 23%. In addition to providing new information on the regeneration of murine corneal nerves, this study presents evidence that VEGF signaling influences the repair of corneal nerves by demonstrating that VEGF and VEGF receptors are present in the trigeminal ganglia and that abrogation of VEGF signaling reduces nerve growth in vitro and in vivo.

  11. Vascular endothelial growth factor and fibroblast growth factor 2 delivery from spinal cord bridges to enhance angiogenesis following injury.

    PubMed

    De Laporte, Laura; des Rieux, Anne; Tuinstra, Hannah M; Zelivyanskaya, Marina L; De Clerck, Nora M; Postnov, Andrei A; Préat, Véronique; Shea, Lonnie D

    2011-09-01

    The host response to spinal cord injury can lead to an ischemic environment that can induce cell death and limits cell transplantation approaches to promote spinal cord regeneration. Spinal cord bridges that provide a localized and sustained release of vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF-2) were investigated for their ability to promote angiogenesis and nerve growth within the injury. Bridges were fabricated by fusion of poly(lactide-co-glycolide) microspheres using a gas foaming/particulate leaching technique, and proteins were incorporated by encapsulation into the microspheres and/or mixing with the microspheres before foaming. Compared to the mixing method, encapsulation reduced the losses during leaching and had a slower protein release, while VEGF was released more rapidly than FGF-2. In vivo implantation of bridges loaded with VEGF enhanced the levels of VEGF within the injury at 1 week, and bridges releasing VEGF and FGF-2 increased the infiltration of endothelial cells and the formation of blood vessel at 6 weeks postimplantation. Additionally, substantial neurofilament staining was observed within the bridge; however, no significant difference was observed between bridges with or without protein. Bridges releasing angiogenic factors may provide an approach to overcome an ischemic environment that limits regeneration and cell transplantation-based approaches. Copyright © 2011 Wiley Periodicals, Inc.

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

    PubMed Central

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

    1999-01-01

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

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

    SciTech Connect

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

    1987-05-01

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

  14. Vascular endothelial growth factor stimulates osteoblastic differentiation of cultured human periosteal-derived cells expressing vascular endothelial growth factor receptors.

    PubMed

    Hah, Young-Sool; Jun, Jin-Su; Lee, Seong-Gyun; Park, Bong-Wook; Kim, Deok Ryong; Kim, Uk-Kyu; Kim, Jong-Ryoul; Byun, June-Ho

    2011-02-01

    Angiogenesis plays an important role in bone development and postnatal bone fracture repair. Vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors (VEGFRs) are primarily involved in angiogenesis. This study investigated the expression of VEGF isoforms, VEGFR-1, and VEGFR-2 during the osteoblastic differentiation of cultured human periosteal-derived cells. In addition, the effect of exogenous VEGF on the osteoblastic differentiation of cultured human periosteal-derived cells was also examined. The expression of the VEGF isoforms (VEGF(121), VEGF(165), VEGF(189), and VEGF(206)), VEGFR-1, and VEGFR-2 was observed in the periosteal-derived cells. Administration of KRN633, a VEGFR-1 and VEGFR-2 inhibitor, decreased the alkaline phosphatase (ALP) activity during the osteoblastic differentiation of cultured human periosteal-derived cells. However, the administration of VEGFR2 Kinase Inhibitor IV, a VEGFR-2 inhibitor, did not affect the ALP activity. The addition of recombinant human VEGF(165) elevated the ALP activity and increased the calcium content in the periosteal-derived cells. Treating the periosteal-derived cells with recombinant human VEGF(165) resulted in an increase in Runx2 transactivation in the periosteal-derived cells. These results suggest that exogenous VEGF stimulates the osteoblastic differentiation of cultured human periosteal-derived cells and VEGF might act as an autocrine growth factor for the osteoblastic differentiation of cultured human periosteal-derived cells.

  15. Basic fibroblast growth factor promotes macaque follicle development in vitro.

    PubMed

    Lu, C L; Yan, J; Zhi, X; Xia, X; Wang, T R; Yan, L Y; Yu, Y; Ding, T; Gao, J M; Li, R; Qiao, J

    2015-05-01

    Fertility preservation is an important type of frontier scientific research in the field of reproductive health. The culture of ovarian cortices to i) initiate primordial follicle growth and ii) procure developing follicles for later oocyte maturation is a promising fertility preservation strategy, especially for older women or cancer patients. At present, this goal remains largely unsubstantiated in primates because of the difficulty in attaining relatively large follicles via ovarian cortex culture. To overcome this hurdle, we cultured macaque monkey ovarian cortices with FSH, kit ligand (KL), basic fibroblast growth factor (bFGF), and/or epidermal growth factor (EGF). The various factors and factor combinations promoted primordial follicle development to different extents. Notably, both bFF (bFGF, 100 ng/ml and FSH, 50 ng/ml) and KF (KL, 100 ng/ml and FSH, 50 ng/ml) contributed to the activation of primordial follicles at day 12 (D12) of culture, whereas at D18, the proportions of developing follicles were significantly higher in the bFF and KF groups relative to the other treatment groups, particularly in the bFF group. Estradiol and progesterone production were also highest in the bFF group, and primary follicle diameters were the largest. Up until D24, the bFF group still exhibited the highest proportion of developing follicles. In conclusion, the bFGF-FSH combination promotes nonhuman primate primordial follicle development in vitro, with the optimal experimental window within 18 days. These results provide evidence for the future success of human ovarian cortex culture and the eventual acquisition of mature human follicles or oocytes for fertility restoration. © 2015 Society for Reproduction and Fertility.

  16. 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.

  17. Hepatocyte growth factor in renal failure: promise and reality.

    PubMed

    Vargas, G A; Hoeflich, A; Jehle, P M

    2000-04-01

    Can science discover some secrets of Greek mythology? In the case of Prometheus, we can now suppose that his amazing hepatic regeneration was caused by a peptide growth factor called hepatocyte growth factor (HGF). Increasing evidence indicates that HGF acts as a multifunctional cytokine on different cell types. This review addresses the molecular mechanisms that are responsible for the pleiotropic effects of HGF. HGF binds with high affinity to its specific tyrosine kinase receptor c-met, thereby stimulating not only cell proliferation and differentiation, but also cell migration and tumorigenesis. The three fundamental principles of medicine-prevention, diagnosis, and therapy-may be benefited by the rational use of HGF. In renal tubular cells, HGF induces mitogenic and morphogenetic responses. In animal models of toxic or ischemic acute renal failure, HGF acts in a renotropic and nephroprotective manner. HGF expression is rapidly up-regulated in the remnant kidney of nephrectomized rats, inducing compensatory growth. In a mouse model of chronic renal disease, HGF inhibits the progression of tubulointerstitial fibrosis and kidney dysfunction. Increased HGF mRNA transcripts were detected in mesenchymal and tubular epithelial cells of rejecting kidney. In transplanted patients, elevated HGF levels may indicate renal rejection. When HGF is considered as a therapeutic agent in human medicine, for example, to stimulate kidney regeneration after acute injury, strategies need to be developed to stimulate cell regeneration and differentiation without an induction of tumorigenesis.

  18. 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

  19. Role of fibroblast growth factor receptor signaling in kidney development.

    PubMed

    Bates, Carlton M

    2011-08-01

    Fibroblast growth factor receptors (Fgfrs) consist of four signaling family members and one nonsignaling "decoy" receptor, Fgfr-like 1 (Fgfrl1), all of which are expressed in the developing kidney. Several studies have shown that exogenous fibroblast growth factors (Fgfs) affect growth and maturation of the metanephric mesenchyme (MM) and ureteric bud (UB) in cultured tissues. Transgenic and conditional knockout approaches in whole animals have shown that Fgfr1 and Fgfr2 (predominantly the IIIc isoform) in kidney mesenchyme are critical for early MM and UB formation. Conditional deletion of the ligand, Fgf8, in nephron precursors or global deletion of Fgfrl1 interrupts nephron formation. Fgfr2 (likely the IIIb isoform signaling downstream of Fgf7 and Fgf10) is critical for ureteric morphogenesis. Moreover, Fgfr2 appears to act independently of Frs2α (the major signaling adapter for Fgfrs) in regulating UB branching. Loss of Fgfr2 in the MM leads to many kidney and urinary tract anomalies, including vesicoureteral reflux. Thus Fgfr signaling is critical for patterning of virtually all renal lineages at early and later stages of development.

  20. Role of fibroblast growth factor receptor signaling in kidney development.

    PubMed

    Bates, Carlton M

    2011-09-01

    Fibroblast growth factor receptors (Fgfrs) are expressed throughout the developing kidney. Several early studies have shown that exogenous fibroblast growth factors (Fgfs) affect growth and maturation of the metanephric mesenchyme (MM) and ureteric bud (UB). Transgenic mice that over-express a dominant negative receptor isoform develop renal aplasia/severe dysplasia, confirming the importance of Fgfrs in renal development. Furthermore, global deletion of Fgf7, Fgf10, and Fgfr2IIIb (isoform that binds Fgf7 and Fgf10) in mice leads to small kidneys with fewer collecting ducts and nephrons. Deletion of Fgfrl1, a receptor lacking intracellular signaling domains, causes severe renal dysgenesis. Conditional targeting of Fgf8 from the MM interrupts nephron formation. Deletion of Fgfr2 from the UB results in severe ureteric branching and stromal mesenchymal defects, although loss of Frs2α (major signaling adapter for Fgfrs) in the UB causes only mild renal hypoplasia. Deletion of both Fgfr1 and Fgfr2 in the MM results in renal aplasia with defects in MM formation and initial UB elongation and branching. Loss of Fgfr2 in the MM leads to many renal and urinary tract anomalies as well as vesicoureteral reflux. Thus, Fgfr signaling is critical for patterning of virtually all renal lineages at early and later stages of development.

  1. Production of human epidermal growth factor using adenoviral based system

    PubMed Central

    Negahdari, Babak; Shahosseini, Zahra; Baniasadi, Vahid

    2016-01-01

    Epidermal growth factor (EGF), a growth factor involved in cell growth and differentiation, is a small polypeptide with molecular weight of approximately 6 kDa known to be present in a number of different mammalian species. Experimental studies in animals and humans have demonstrated that the topical application of EGF accelerates the rate of epidermal regeneration of partial-thickness wounds and second-degree burns. Due to its commercial applications, Human EGF (hEGF) has been cloned in several forms. In the present study, adenoviral based expression system was used to produce biologically active recombinant hEGF. The presence of secreted recombinant hEGF was confirmed by a dot blot and its expression level was determined by enzyme-linked immuno-sorbent assay. Moreover, biological activity of secreted hEGF was evaluated by a proliferation assay performed on A549 cells. For production of hEGF in a secretory form, a chimeric gene coding for the hEGF fused to the signal peptide was expressed using adenoviral based method. This method enables the production of hEGF at the site of interest and moreover it could be used for cell proliferation and differentiation assays in tissue engineering research experiments instead of using commercially available EGF. PMID:27051431

  2. Transcription factor LSF (TFCP2) inhibits melanoma growth

    PubMed Central

    Goto, Yuji; Yajima, Ichiro; Kumasaka, Mayuko; Ohgami, Nobutaka; Tanaka, Asami; Tsuzuki, Toyonori; Inoue, Yuji; Fukushima, Satoshi; Ihn, Hironobu; Kyoya, Mikiko; Ohashi, Hiroyuki; Kawakami, Tamihiro; Bennett, Dorothy C.; Kato, Masashi

    2016-01-01

    Late SV40 factor 3 (LSF), a transcription factor, contributes to human hepatocellular carcinoma (HCC). However, decreased expression level of LSF in skin melanoma compared to that in benign melanocytic tumors and nevi in mice and humans was found in this study. Anchorage-dependent and -independent growth of melanoma cells was suppressed by LSF overexpression through an increased percentage of G1 phase cells and an increased p21CIP1 expression level in vitro and in vivo. Anchorage-dependent growth in LSF-overexpressed melanoma cells was promoted by depletion of LSF in the LSF-overexpressed cells. Integrated results of our EMSA and chromatin immunoprecipitation assays showed binding of LSF within a 150-bp upstream region of the transcription start site of p21CIP1 in melanoma cells. Taken together, our results suggest potential roles of LSF as a growth regulator through control of the transcription of p21CIP1 in melanocytes and melanoma cells as well as a biomarker for nevus. PMID:26506241

  3. Myogenic regulatory transcription factors regulate growth in rhabdomyosarcoma

    PubMed Central

    Tenente, Inês M; Hayes, Madeline N; Ignatius, Myron S; McCarthy, Karin; Yohe, Marielle; Sindiri, Sivasish; Gryder, Berkley; Oliveira, Mariana L; Ramakrishnan, Ashwin; Tang, Qin; Chen, Eleanor Y; Petur Nielsen, G; Khan, Javed; Langenau, David M

    2017-01-01

    Rhabdomyosarcoma (RMS) is a pediatric malignacy of muscle with myogenic regulatory transcription factors MYOD and MYF5 being expressed in this disease. Consensus in the field has been that expression of these factors likely reflects the target cell of transformation rather than being required for continued tumor growth. Here, we used a transgenic zebrafish model to show that Myf5 is sufficient to confer tumor-propagating potential to RMS cells and caused tumors to initiate earlier and have higher penetrance. Analysis of human RMS revealed that MYF5 and MYOD are mutually-exclusively expressed and each is required for sustained tumor growth. ChIP-seq and mechanistic studies in human RMS uncovered that MYF5 and MYOD bind common DNA regulatory elements to alter transcription of genes that regulate muscle development and cell cycle progression. Our data support unappreciated and dominant oncogenic roles for MYF5 and MYOD convergence on common transcriptional targets to regulate human RMS growth. DOI: http://dx.doi.org/10.7554/eLife.19214.001 PMID:28080960

  4. Insulin-like growth factors and kidney disease.

    PubMed

    Bach, Leon A; Hale, Lorna J

    2015-02-01

    Insulin-like growth factors (IGF-1 and IGF-2) are necessary for normal growth and development. They are related structurally to proinsulin and promote cell proliferation, differentiation, and survival, as well as insulin-like metabolic effects, in most cell types and tissues. In particular, IGFs are important for normal pre- and postnatal kidney development. IGF-1 mediates many growth hormone actions, and both growth hormone excess and deficiency are associated with perturbed kidney function. IGFs affect renal hemodynamics both directly and indirectly by interacting with the renin-angiotensin system. In addition to the IGF ligands, the IGF system includes receptors for IGF-1, IGF-2/mannose-6-phosphate, and insulin, and a family of 6 high-affinity IGF-binding proteins that modulate IGF action. Disordered regulation of the IGF system has been implicated in a number of kidney diseases. IGF activity is enhanced in early diabetic nephropathy and polycystic kidneys, whereas IGF resistance is found in chronic kidney failure. IGFs have a potential role in enhancing stem cell repair of kidney injury. Most IGF actions are mediated by the tyrosine kinase IGF-1 receptor, and inhibitors recently have been developed. Further studies are needed to determine the optimal role of IGF-based therapies in kidney disease. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  5. Free insulin-like growth factors in human obesity.

    PubMed

    Frystyk, J; Vestbo, E; Skjaerbaek, C; Mogensen, C E; Orskov, H

    1995-10-01

    It is well established that spontaneous and stimulated growth hormone (GH) secretion is diminished in human obesity. In contrast to classic GH deficiency, obesity is not associated with hypopituitary levels of circulating total (extractable) insulin-like growth factor-I (IGF-I) and reduced somatic growth. Thus, the riddle of "normal growth without GH" in obese children and the mechanisms behind the GH suppression have remained unsolved. Insulin reduces hepatic production of IGF-binding protein-1 (IGFBP-1), an in vitro inhibitor of IGF bioactivity, and it has been suggested that the obesity-related hyperinsulinemia may increase free (bioactive) IGF in vivo by reducing the concentration of IGFBP-1. We have recently developed a method that during near in vivo conditions isolates the free, unbound fractions of IGF-I and IGF-II in human serum. Using this method, we have determined overnight fasting serum levels of free IGFs in obese subjects and compared the results with levels of total (extractable) IGFs, IGFBPs, GH, and insulin. The study included 92 healthy subjects (56 males and 36 females) allocated to three age-matched groups depending on body mass index (BMI): 31 controls (BMI < or = 25), 33 subjects with moderate obesity (25 < BMI < 30), and 28 subjects with severe obesity (BMI > or = 30). Fasting serum insulin correlated positively (r = .61, P < .0001) with BMI and was significantly elevated in moderate and severe obesity (P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Environmental estrogens inhibit growth of rainbow trout (Oncorhynchus mykiss) by modulating the growth hormone-insulin-like growth factor system.

    PubMed

    Hanson, Andrea M; Kittilson, Jeffrey D; Martin, Lincoln E; Sheridan, Mark A

    2014-01-15

    Although environmental estrogens (EE) have been found to disrupt a wide variety of developmental and reproductive processes in vertebrates, there is a paucity of information concerning their effects on organismal growth, particularly postembryonic growth. In this study, we exposed juvenile rainbow trout (Oncorhynchus mykiss) to 17β-estradiol (E2) β-sitosterol (βS), or 4-n-nonylphenol (NP) to assess the effects of EE on overall organismal growth and on the growth hormone-insulin-like-growth factor (GH-IGF) system. EE treatment significantly reduced food conversion, body condition, and body growth. EE-inhibited growth resulted from alterations in peripheral elements of the GH-IGF system, which includes multiple GH receptors (GHRs), IGFs, and IGF receptors (IGFRs). In general, E2, βS, and NP reduced the expression of GHRs, IGFs, and IGFRs; however, the effects varied in an EE-, tissue-, element type-specific manner. For example, in liver, E2 was more efficacious than either βS, and NP in reducing GHR expression, and the effect of E2 was greater on GHR 1 than GHR2 mRNA. By contrast, in gill, all EEs affected GHR expression in a similar manner and there was no difference in the effect on GHR1 and GHR 2 mRNA. With regard to IGF expression, all EEs reduced hepatic IGF1 and IGF2 mRNA levels, whereas as in gill, only E2 and NP significantly reduced IGF1 and IGF2 expression. Lastly, E2 and NP reduced the expression of IGFR1A and IGFR1B mRNA expression similarly in gill and red and white muscle, whereas βS had no effect on expression of IGFR mRNAs. These findings indicate that EEs disrupt post-embryonic growth by reducing GH sensitivity, IGF production, and IGF sensitivity. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Effects of Hypergravity Rearing on Growth Hormone and Insulin-Like Growth Factor in Rat Pups

    NASA Technical Reports Server (NTRS)

    Baer, L. A.; Chowdhury, J. H.; Grindeland, R. E.; Wade, C. E.; Ronca, A. E.

    2003-01-01

    Body weights of rat pups reared during exposure to hypergravity (hg) are significantly reduced relative to 1 g controls. In the present study, we examined in hg-reared rat pups two major contributors to growth and development, namely growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Beginning on Gestational day (G)11 of the rats 22 day pregnancy, rat dams and their litters were continuously exposed to either 1.5-g or 2.0-g. On Postnatal day (P)l0, plasma GH and IGF-1 were analyzed using radioimmunoassay (RIA). Both hormones were significantly elevated in hg pups relative to 1-g control pups. Together, these findings suggest that GH and IGF-1 are not primary determinants of reduced body weights observed in hg-reared pups. The significant elevations in pup GH and IGF-1 may be related to increased physical stimulation in hypergravity.

  8. Effects of Hypergravity Rearing on Growth Hormone and Insulin-Like Growth Factor in Rat Pups

    NASA Technical Reports Server (NTRS)

    Baer, L. A.; Chowdhury, J. H.; Grindeland, R. E.; Wade, C. E.; Ronca, A. E.

    2003-01-01

    Body weights of rat pups reared during exposure to hypergravity (hg) are significantly reduced relative to 1 g controls. In the present study, we examined in hg-reared rat pups two major contributors to growth and development, namely growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Beginning on Gestational day (G)11 of the rats 22 day pregnancy, rat dams and their litters were continuously exposed to either 1.5-g or 2.0-g. On Postnatal day (P)l0, plasma GH and IGF-1 were analyzed using radioimmunoassay (RIA). Both hormones were significantly elevated in hg pups relative to 1-g control pups. Together, these findings suggest that GH and IGF-1 are not primary determinants of reduced body weights observed in hg-reared pups. The significant elevations in pup GH and IGF-1 may be related to increased physical stimulation in hypergravity.

  9. 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

  10. Modeling the effect of insulin-like growth factor-1 on human cell growth.

    PubMed

    Phillips, Gemma M A; Shorten, Paul R; Wake, Graeme C; Guan, Jian

    2015-01-01

    Insulin-like growth factor-1 (IGF-1) plays a key role in human growth and development. The interactions of IGF-1 with IGF-1 receptors and IGF-1 binding proteins (IGFBPs) regulate IGF-1 function. Recent research suggests that a metabolite of IGF-1, cyclo-glycyl-proline (cGP), has a role in regulating IGF-1 homeostasis. A component of this interaction is believed to be the competitive binding of IGF-1 and cGP to IGFBPs. In this paper we describe a mathematical model of the interaction between IGF-1 and cGP on human cell growth. The model can be used to understand the interaction between IGF-1, IGFBPs, cGP and IGF-1 receptors along with the kinetics of cell growth. An explicit model of the known interactions between IGF-1, cGP, IGFBPs, IGF-1 receptors explained a large portion of the variance in cell growth (R(2) = 0.83). An implicit model of the interactions between IGF-1, cGP, IGFBPs, IGF-1 receptors that included a hypothesized feedback of cGP on IGF-1 receptors explained nonlinear features of interaction between IGF-1 and cGP not described by the explicit model (R(2) = 0.84). The model also explained the effect of IGFBP antibody on the interaction between cGP and IGF-1 (R(2) = 0.78). This demonstrates that the competitive binding of IGF-1 and cGP to IGFBPs plays a large role in the interaction between IGF-1 and cGP, but that other factors potentially play a role in the interaction between cGP and IGF-1. These models can be used to predict the complex interaction between IGF-1 and cGP on human cell growth and form a basis for further research in this field.

  11. Insulin-Like Growth Factor Binding Proteins--an Update.

    PubMed

    Bach, Leon A

    2015-12-01

    The insulin-like growth factor (IGF) system is essential for normal growth and development, and its perturbation is implicated in a number of diseases. IGF activity is finely regulated by a family of six high-affinity IGF binding proteins (IGFBPs). 1GFBPs usually inhibit IGF actions but may enhance them under certain conditions. Additionally, IGFBPs bind non-IGF ligands in the extracellular space, cell membrane, cytoplasm and nucleus, thereby modulating cell proliferation, survival and migration in an IGF-independent manner. IGFBP activity is regulated by transcriptional mechanisms as well as by post-translational modifications and proteolysis. Understanding the balance between the various actions of IGFBPs in vivo may lead to novel insights into disease processes and possible IGFBP-based therapeutics.

  12. Signal Transduction by Vascular Endothelial Growth Factor Receptors

    PubMed Central

    Koch, Sina; Claesson-Welsh, Lena

    2012-01-01

    Vascular endothelial growth factors (VEGFs) are master regulators of vascular development and of blood and lymphatic vessel function during health and disease in the adult. It is therefore important to understand the mechanism of action of this family of five mammalian ligands, which act through three receptor tyrosine kinases (RTKs). In addition, coreceptors like neuropilins (NRPs) and integrins associate with the ligand/receptor signaling complex and modulate the output. Therapeutics to block several of the VEGF signaling components have been developed with the aim to halt blood vessel formation, angiogenesis, in diseases that involve tissue growth and inflammation, such as cancer. In this review, we outline the current information on VEGF signal transduction in relation to blood and lymphatic vessel biology. PMID:22762016

  13. Anti-Vascular Endothelial Growth Factor Therapy in Breast Cancer

    PubMed Central

    Kristensen, Tina Bøgelund; Knutsson, Malin L. T.; Wehland, Markus; Laursen, Britt Elmedal; Grimm, Daniela; Warnke, Elisabeth; Magnusson, Nils E.

    2014-01-01

    Neo-angiogenesis is a critical process for tumor growth and invasion and has become a promising target in cancer therapy. This manuscript reviews three currently relevant anti-angiogenic agents targeting the vascular endothelial growth factor system: bevacizumab, ramucirumab and sorafenib. The efficacy of anti-angiogenic drugs in adjuvant therapy or as neo-adjuvant treatment has been estimated in clinical trials of advanced breast cancer. To date, the overall observed clinical improvements are unconvincing, and further research is required to demonstrate the efficacy of anti-angiogenic drugs in breast cancer treatments. The outcomes of anti-angiogenic therapy have been highly variable in terms of tumor response. New methods are needed to identify patients who will benefit from this regimen. The development of biomarkers and molecular profiling are relevant research areas that may strengthen the ability to focus anti-angiogenic therapy towards suitable patients, thereby increase the cost-effectiveness, currently estimated to be inadequate. PMID:25514409

  14. A comprehensive pathway map of epidermal growth factor receptor signaling

    PubMed Central

    Oda, Kanae; Matsuoka, Yukiko; Funahashi, Akira; Kitano, Hiroaki

    2005-01-01

    The epidermal growth factor receptor (EGFR) signaling pathway is one of the most important pathways that regulate growth, survival, proliferation, and differentiation in mammalian cells. Reflecting this importance, it is one of the best-investigated signaling systems, both experimentally and computationally, and several computational models have been developed for dynamic analysis. A map of molecular interactions of the EGFR signaling system is a valuable resource for research in this area. In this paper, we present a comprehensive pathway map of EGFR signaling and other related pathways. The map reveals that the overall architecture of the pathway is a bow-tie (or hourglass) structure with several feedback loops. The map is created using CellDesigner software that enables us to graphically represent interactions using a well-defined and consistent graphical notation, and to store it in Systems Biology Markup Language (SBML). PMID:16729045

  15. Insulin-Like Growth Factor System and Sporadic Malignant Melanoma

    PubMed Central

    Capoluongo, Ettore

    2011-01-01

    Insulin and insulin-like growth factors (IGFs) are important regulators of energy metabolism and growth. Several findings have outlined an important role played by this family of molecules in both tumor maintenance and development. Despite the established contribution of the IGF system in carcinogenesis, little and contrasting data have been reported concerning the intertwined relationships between melanoma and this family of molecules. The present minireview aims to summarize the main topics and evidence concerning this malignant skin cancer, with a focus on the following: i) melanoma and cell proliferation effects induced by the IGF system, ii) in vitro and in vivo experimental data, and iii) targeting studies. Because of consistent findings regarding the role of the IGF-1 receptor in the modulation of IGF-1 activity, possible therapeutic strategies combining the use of antisense oligonucleotides against IGF-1 receptor mRNA could be applied in the future. PMID:21224039

  16. Release characteristics of encapsulated formulations incorporating plant growth factors.

    PubMed

    Wybraniec, Slawomir; Schwartz, Liliana; Wiesman, Zeev; Markus, Arie; Wolf, David

    2002-05-01

    The release characteristics of encapsulated formulations containing a combination of plant growth factors (PGF)--plant hormones (IBA, paclobutrazol), nutrients (fertilizers, microelements), and fungicide (prochloraz)--were studied. The formulations were prepared by encapsulating the active ingredients in a polyethylene matrix and, in some cases, subsequently coating the product with polyurethane. Dissolution experiments were carried out with both coated and non-coated formulations to determine the sustained release patterns of the active ingredients. The PGF controlled-release systems obtained have been shown to promote development of root systems, vegetative growth, and reproductive development in cuttings, potted plants, or garden plants of various plant species. These beneficial effects are attributable to the lasting and balanced PGF availability provided by these systems.

  17. Rapamycin promotes Schwann cell migration and nerve growth factor secretion

    PubMed Central

    Liu, Fang; Zhang, Haiwei; Zhang, Kaiming; Wang, Xinyu; Li, Shipu; Yin, Yixia

    2014-01-01

    Rapamycin, similar to FK506, can promote neural regeneration in vitro. We assumed that the mechanisms of action of rapamycin and FK506 in promoting peripheral nerve regeneration were similar. This study compared the effects of different concentrations of rapamycin and FK506 on Schwann cells and investigated effects and mechanisms of rapamycin on improving peripheral nerve regeneration. Results demonstrated that the lowest rapamycin concentration (1.53 nmol/L) more significantly promoted Schwann cell migration than the highest FK506 concentration (100μmol/L). Rapamycin promoted the secretion of nerve growth factors and upregulated growth-associated protein 43 expression in Schwann cells, but did not significantly affect Schwann cell proliferation. Therefore, rapamycin has potential application in peripheral nerve regeneration therapy. PMID:25206862

  18. Blockade of nonhormonal fibroblast growth factors by FP-1039 inhibits growth of multiple types of cancer.

    PubMed

    Harding, Thomas C; Long, Li; Palencia, Servando; Zhang, Hongbing; Sadra, Ali; Hestir, Kevin; Patil, Namrata; Levin, Anita; Hsu, Amy W; Charych, Deborah; Brennan, Thomas; Zanghi, James; Halenbeck, Robert; Marshall, Shannon A; Qin, Minmin; Doberstein, Stephen K; Hollenbaugh, Diane; Kavanaugh, W Michael; Williams, Lewis T; Baker, Kevin P

    2013-03-27

    The fibroblast growth factor (FGF) pathway promotes tumor growth and angiogenesis in many solid tumors. Although there has long been interest in FGF pathway inhibitors, development has been complicated: An effective FGF inhibitor must block the activity of multiple mitogenic FGF ligands but must spare the metabolic hormone FGFs (FGF-19, FGF-21, and FGF-23) to avoid unacceptable toxicity. To achieve these design requirements, we engineered a soluble FGF receptor 1 Fc fusion protein, FP-1039. FP-1039 binds tightly to all of the mitogenic FGF ligands, inhibits FGF-stimulated cell proliferation in vitro, blocks FGF- and vascular endothelial growth factor (VEGF)-induced angiogenesis in vivo, and inhibits in vivo growth of a broad range of tumor types. FP-1039 antitumor response is positively correlated with RNA levels of FGF2, FGF18, FGFR1c, FGFR3c, and ETV4; models with genetic aberrations in the FGF pathway, including FGFR1-amplified lung cancer and FGFR2-mutated endometrial cancer, are particularly sensitive to FP-1039-mediated tumor inhibition. FP-1039 does not appreciably bind the hormonal FGFs, because these ligands require a cell surface co-receptor, klotho or β-klotho, for high-affinity binding and signaling. Serum calcium and phosphate levels, which are regulated by FGF-23, are not altered by administration of FP-1039. By selectively blocking nonhormonal FGFs, FP-1039 treatment confers antitumor efficacy without the toxicities associated with other FGF pathway inhibitors.

  19. Diabetes, growth hormone-insulin-like growth factor pathways and association to benign prostatic hyperplasia.

    PubMed

    Wang, Zongwei; Olumi, Aria F

    2011-01-01

    Diabetes significantly increases the risk of benign prostatic hyperplasia (BPH) and low urinary tract symptoms (LUTS). The major endocrine aberration in connection with the metabolic syndrome is hyperinsulinemia. Insulin is an independent risk factor and a promoter of BPH. Insulin resistance may change the risk of BPH through several biological pathways. Hyperinsulinemia stimulates the liver to produce more insulin-like growth factor (IGF), another mitogen and an anti-apoptotic agent which binds insulin receptor/IGF receptor and stimulates prostate growth. The levels of IGFs and IGF binding proteins (IGFBPs) in prostate tissue and in blood are associated with BPH risk, with the regulation of circulating androgen and growth hormone. Stromal-epithelial interactions play a critical role in the development and growth of the prostate gland and BPH. Previously, we have shown that the expression of c-Jun in the fibroblastic stroma can promote secretion of IGF-I, which stimulates prostate epithelial cell proliferation through activating specific target genes. Here, we will review the epidemiologic, clinical, and molecular findings which have evaluated the relation between diabetes and development of BPH.

  20. The trend and the disease prediction of vascular endothelial growth factor and placenta growth factor in nontuberculous mycobacterial lung disease

    PubMed Central

    Lin, Chou-Han; Shu, Chin-Chung; Hsu, Chia-Lin; Cheng, Shih-Lung; Wang, Jann-Yuan; Yu, Chong-Jen; Lee, Li-Na

    2016-01-01

    Nontuberculous mycobacteria (NTM)-lung disease (LD) is an increasing health problem worldwide. The diagnosis of this disease remains difficult, however the application of placenta growth factor (PlGF) and vascular endothelial growth factor (VEGF) has not yet been studied. We screened patients with Mycobacterium avium complex or M. abscessus isolated from sputum, and enrolled 32 patients with NTM-LD and 93 with NTM pulmonary colonization. The NTM-LD group had a lower body mass index, higher proportion of bronchiectasis, more respiratory symptoms and pulmonary lesions, and higher titers of sputum acid-fast stain than the NTM pulmonary colonization group. The plasma level of PlGF was lower in the NTM-LD group than in the NTM colonization group, whereas the level of VEGF was higher in the NTM-LD group. In multivariable logistic regression analysis excluding NTM cultures, the predictive model for NTM-LD included sputum AFS titer, a nodular-bronchiectasis radiographic pattern, plasma VEGF/PlGF ratio, and chest radiographic score (VEGF/P1GF ratio became not significant as a factor in multivariable generalized linear model). The four-factor predictive index had good positive likelihood ratio and negative likelihood ratio for predicting NTM-LD in the patients with NTM in their sputum. PMID:27876856

  1. Insulin-Like Growth Factor Binding Proteins: A Structural Perspective

    PubMed Central

    Forbes, Briony E.; McCarthy, Peter; Norton, Raymond S.

    2012-01-01

    Insulin-like growth factor binding proteins (IGFBP-1 to -6) bind insulin-like growth factors-I and -II (IGF-I and IGF-II) with high affinity. These binding proteins maintain IGFs in the circulation and direct them to target tissues, where they promote cell growth, proliferation, differentiation, and survival via the type 1 IGF receptor. IGFBPs also interact with many other molecules, which not only influence their modulation of IGF action but also mediate IGF-independent activities that regulate processes such as cell migration and apoptosis by modulating gene transcription. IGFBPs-1 to -6 are structurally similar proteins consisting of three distinct domains, N-terminal, linker, and C-terminal. There have been major advances in our understanding of IGFBP structure in the last decade and a half. While there is still no structure of an intact IGFBP, several structures of individual N- and C-domains have been solved. The structure of a complex of N-BP-4:IGF-I:C-BP-4 has also been solved, providing a detailed picture of the structural features of the IGF binding site and the mechanism of binding. Structural studies have also identified features important for interaction with extracellular matrix components and integrins. This review summarizes structural studies reported so far and highlights features important for binding not only IGF but also other partners. We also highlight future directions in which structural studies will add to our knowledge of the role played by the IGFBP family in normal growth and development, as well as in disease. PMID:22654863

  2. Mechanotransduction and Growth Factor Signalling to Engineer Cellular Microenvironments.

    PubMed

    Cipitria, Amaia; Salmeron-Sanchez, Manuel

    2017-08-01

    Engineering cellular microenvironments involves biochemical factors, the extracellular matrix (ECM) and the interaction with neighbouring cells. This progress report provides a critical overview of key studies that incorporate growth factor (GF) signalling and mechanotransduction into the design of advanced microenvironments. Materials systems have been developed for surface-bound presentation of GFs, either covalently tethered or sequestered through physico-chemical affinity to the matrix, as an alternative to soluble GFs. Furthermore, some materials contain both GF and integrin binding regions and thereby enable synergistic signalling between the two. Mechanotransduction refers to the ability of the cells to sense physical properties of the ECM and to transduce them into biochemical signals. Various aspects of the physics of the ECM, i.e. stiffness, geometry and ligand spacing, as well as time-dependent properties, such as matrix stiffening, degradability, viscoelasticity, surface mobility as well as spatial patterns and gradients of physical cues are discussed. To conclude, various examples illustrate the potential for cooperative signalling of growth factors and the physical properties of the microenvironment for potential applications in regenerative medicine, cancer research and drug testing. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    PubMed Central

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

    1988-01-01

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

  4. A role for platelet-derived growth factor-BB in rat postpneumonectomy compensatory lung growth.

    PubMed

    Yuan, Shizeng; Hannam, Vicky; Belcastro, Rosetta; Cartel, Nicholas; Cabacungan, Judy; Wang, Jinxia; Diambomba, Yenge; Johnstone, Leslie; Post, Martin; Tanswell, A Keith

    2002-07-01

    Unilateral pneumonectomy leads to compensatory growth in the residual lung, the mediators of which are largely unknown. We hypothesized, based on its other known roles in lung cell growth, that platelet-derived growth factor (PDGF)-BB would be an essential mediator of postpneumonectomy compensatory lung growth. Left-sided pneumonectomies were performed on 21-d-old rats, for comparison with sham-operated or unoperated control animals. Body weights were not different between groups. Right lung weights and DNA content were significantly increased (p < 0.05), compared with controls, by 10 d after pneumonectomy. The rate of DNA synthesis was maximal on d 5 postpneumonectomy. Total right lung PDGF-B mRNA and PDGF-BB protein increased after pneumonectomy, but were apparently tightly regulated, relative to total right lung beta-actin mRNA and protein content, respectively. However, PDGF-BB expression after pneumonectomy was apparently not purely constitutive, in that daily i.p. injections of a truncated soluble PDGF beta-receptor both reduced activation of the native PDGF beta-receptor, and attenuated increased lung DNA synthesis on d 3 after pneumonectomy. These findings are consistent with a critical role for PDGF-BB in postpneumonectomy lung growth.

  5. Nerve growth factor released from a novel PLGA nerve conduit can improve axon growth

    NASA Astrophysics Data System (ADS)

    Lin, Keng-Min; Shea, Jill; Gale, Bruce K.; Sant, Himanshu; Larrabee, Patti; Agarwal, Jay

    2016-04-01

    Nerve injury can occur due to penetrating wounds, compression, traumatic stretch, and cold exposure. Despite prompt repair, outcomes are dismal. In an attempt to help resolve this challenge, in this work, a poly-lactic-co-glycolic acid (PLGA) nerve conduit with associated biodegradable drug reservoir was designed, fabricated, and tested. Unlike current nerve conduits, this device is capable of fitting various clinical scenarios by delivering different drugs without reengineering the whole system. To demonstrate the potential of this device for nerve repair, a series of experiments were performed using nerve growth factor (NGF). First, an NGF dosage curve was developed to determine the minimum NGF concentration for optimal axonal outgrowth on chick dorsal root ganglia (DRG) cells. Next, PLGA devices loaded with NGF were evaluated for sustained drug release and axon growth enhancement with the released drug. A 20 d in vitro release test was conducted and the nerve conduit showed the ability to meet and maintain the minimum NGF requirement determined previously. Bioactivity assays of the released NGF showed that drug released from the device between the 15th and 20th day could still promote axon growth (76.6-95.7 μm) in chick DRG cells, which is in the range of maximum growth. These novel drug delivery conduits show the ability to deliver NGF at a dosage that efficiently promotes ex vivo axon growth and have the potential for in vivo application to help bridge peripheral nerve gaps.

  6. Mo polyoxometalate nanoparticles inhibit tumor growth and vascular endothelial growth factor induced angiogenesis

    NASA Astrophysics Data System (ADS)

    Zheng, Wenjing; Yang, Licong; Liu, Ying; Qin, Xiuying; Zhou, Yanhui; Zhou, Yunshan; Liu, Jie

    2014-06-01

    Tumor growth depends on angiogenesis, which can furnish the oxygen and nutrients that proliferate tumor cells. Thus, blocking angiogenesis can be an effective strategy to inhibit tumor growth. In this work, three typical nanoparticles based on polyoxometalates (POMs) have been prepared; we investigated their capability as antitumor and anti-angiogenesis agents. We found that Mo POM nanoparticles, especially complex 3, inhibited the growth of human hepatocellular liver carcinoma cells (HepG2) through cellular reactive oxygen species levels’ elevation and mitochondrial membrane potential damage. Complex 3 also suppressed the proliferation, migration, and tube formation of endothelial cells in vitro and chicken chorioallantoic membrane development ex vivo. Furthermore, western blot analysis of cell signaling molecules indicated that Mo POMs blocked the vascular endothelial growth factor receptor 2-mediated ERK1/2 and AKT signaling pathways in endothelial cells. Using transmission electron microscopy, we demonstrated their cellular uptake and localization within the cytoplasm of HepG2 cells. These results indicate that, owing to the extraordinary physical and chemical properties, Mo POM nanoparticles can significantly inhibit tumor growth and angiogenesis, which makes them potential drug candidates in anticancer and anti-angiogenesis therapies.

  7. Vascular Endothelial Growth Factor Receptor -2 in Breast Cancer

    PubMed Central

    Guo, Shanchun; Colbert, Laronna S.; Fuller, Miles; Zhang, Yuanyuan; Gonzalez-Perez, Ruben R.

    2010-01-01

    Investigations over the last decade have established the essential role of growth factors and their receptors during angiogenesis and carcinogenesis. The vascular endothelial growth factor receptor (VEGFR) family in mammals contains three members, VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1) and VEGFR-3 (Flt-4), which are transmembrane tyrosine kinase receptors that regulate the formation of blood and lymphatic vessels. In the early 1990s, the above VEGFR were structurally characterized by cDNA cloning. Among these three receptors, VEGFR-2 is generally recognized to have a principal role in mediating VEGF-induced responses. VEGFR-2 is considered as the earliest marker for endothelial cell development. Importantly, VEGFR-2 directly regulates tumor angiogenesis. Therefore, several inhibitors of VEGFR-2 have been developed and many of them are now in clinical trials. In addition to targeting endothelial cells, the VEGF/VEGFR-2 system works as an essential autocrine/paracrine process for cancer cell proliferation and survival. Recent studies mark the continuous and increased interest in this related, but distinct, function of VEGF/VEGFR-2 in cancer cells: the autocrine/paracrine loop. Several mechanisms regulate VEGFR-2 levels and modulate its role in tumor angiogenesis and physiologic functions, i.e.: cellular localization/trafficking, regulation of cis-elements of promoter, epigenetic regulation and signaling from Notch, cytokines/growth factors and estrogen, etc. In this review, we will focus on updated information regarding VEGFR-2 research with respect to the molecular mechanisms of VEGFR-2 regulation in human breast cancer. Investigations in the activation, function, and regulation of VEGFR-2 in breast cancer will allow the development of new pharmacological strategies aimed at directly targeting cancer cell proliferation and survival. PMID:20462514

  8. 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.

  9. Autologous fibrin glue with growth factors in reconstructive maxillofacial surgery.

    PubMed

    Thorn, J J; Sørensen, H; Weis-Fogh, U; Andersen, M

    2004-01-01

    The aim of this paper was to describe a method for the preparation of autologous fibrin glue with platelet growth factors and to report its use with particulate cancellous bone in reconstructive maxillofacial surgery. The fibrin glue is a two-component glue, where the one component is a concentrated fibrinogen solution with platelet growth factors and the other component is a thrombin solution. Both components were produced from the patients own blood, thus making the glue entirely autologous. The glue was prepared from platelet rich plasma separated from 200 ml of the patient's blood prior to the operation. The fibrinogen in the glue was precipitated from the platelet rich plasma by ethanol precipitation at low temperature and separated together with the platelets by centrifugation. Raising the temperature to 37 degrees C redissolved the precipitate. The thrombin solution in the glue was produced from prothrombin precipitated from 10 ml of the platelet rich plasma by lowering the pH and the ionic strength. The precipitate was separated by centrifugation and dissolved in a calcium ion solution. Increasing the pH to neutral value induced activation to thrombin. Preparation of the fibrin glue was performed in the blood bank within 60 to 90 min with the use of standard equipment. The outcome from 200 ml of blood was approximately 8 ml of fibrin glue: 6 ml fibrinogen to be coagulated with 2 ml of thrombin. The glue had a fibrinogen concentration of approximately 12 times the value in platelet rich plasma and the concentration of growth factors was approximately eight times the value in platelet rich plasma. We have used this glue successfully with particulate bone grafts for reconstructive purposes within the oral and maxillofacial field. It might as well be applied to other surgical areas. Whenever larger amount of the glue will be needed, a whole unit of blood may be taken from the patient, and the red cells re-transfused to the patient during or after the operation.

  10. Growth differentiation factor 5 is a key physiological regulator of dendrite growth during development.

    PubMed

    Osório, Catarina; Chacón, Pedro J; Kisiswa, Lilian; White, Matthew; Wyatt, Sean; Rodríguez-Tébar, Alfredo; Davies, Alun M

    2013-12-01

    Dendrite size and morphology are key determinants of the functional properties of neurons. Here, we show that growth differentiation factor 5 (GDF5), a member of the bone morphogenetic protein (BMP) subclass of the transforming growth factor β superfamily with a well-characterised role in limb morphogenesis, is a key regulator of the growth and elaboration of pyramidal cell dendrites in the developing hippocampus. Pyramidal cells co-express GDF5 and its preferred receptors, BMP receptor 1B and BMP receptor 2, during development. In culture, GDF5 substantially increased dendrite, but not axon, elongation from these neurons by a mechanism that depends on activation of SMADs 1/5/8 and upregulation of the transcription factor HES5. In vivo, the apical and basal dendritic arbours of pyramidal cells throughout the hippocampus were markedly stunted in both homozygous and heterozygous Gdf5 null mutants, indicating that dendrite size and complexity are exquisitely sensitive to the level of endogenous GDF5 synthesis.

  11. The structure of granulocyte-colony-stimulating factor and its relationship to other growth factors.

    PubMed Central

    Hill, C P; Osslund, T D; Eisenberg, D

    1993-01-01

    We have determined the three-dimensional structure of recombinant human granulocyte-colony-stimulating factor by x-ray crystallography. Phases were initially obtained at 3.0-A resolution by multiple isomorphous replacement and were refined by solvent flattening and by averaging of the electron density of the three molecules in the asymmetric unit. The current R factor is 21.5% for all data between 6.0- and 2.2-A resolution. The structure is predominantly helical, with 104 of the 175 residues forming a four-alpha-helix bundle. The only other secondary structure is also helical. In the loop between the first two long helices a four-residue 3(10)-helix is immediately followed by a 6-residue alpha-helix. Three residues in the short connection between the second and third bundle helices form almost one turn of left-handed helix. The up-up-down-down connectivity with two long crossover connections has been reported previously for five other proteins, which like granulocyte-colony-stimulating factor are all signaling ligands: growth hormone, granulocyte/macrophage-colony-stimulating factor, interferon beta, interleukin 2, and interleukin 4. Structural similarity among these growth factors occurs despite the absence of similarity in their amino acid sequences. Conservation of this tertiary structure suggests that these different growth factors might all bind to their respective sequence-related receptors in an equivalent manner. Images Fig. 2 PMID:7685117

  12. Platelet Derived Growth Factor-B and Human Epidermal Growth Factor Receptor-2 Polymorphisms in Gall Bladder Cancer.

    PubMed

    Mishra, Kumudesh; Behari, Anu; Kapoor, Vinay Kumar; Khan, M Salman; Prakash, Swayam; Agrawal, Suraksha

    2015-01-01

    Gall bladder cancer (GBC) is a gastro-intestinal cancer with high prevalence among north Indian women. Platelet derived growth factor-B (PDGFB) and human epidermal growth factor receptor-2 (HER2) may play roles in the etiology of GBC through the inflammation-hyperplasia-dysplasia-carcinoma pathway. To study the association of PDGFB and HER2 polymorphisms with risk of GBC, 200 cases and 300 controls were considered. PDGFB +286A>G and +1135A>C polymorphisms were investigated with an amplification refractory mutation system and the HER2 Ile655Val polymorphism by restriction fragment length polymorphism. Significant risk associations for PDGFB +286 GG (OR=5.25) and PDGFB +1135 CC (OR=3.19) genotypes were observed for GBC. Gender wise stratification revealed susceptibility for recessive models of PDGFB +1135A>C (OR=3.00) and HER2 Ile655Val (OR=2.52) polymorphisms among female GBC cases. GBC cases with gall stones were predisposed to homozygous +286 GG and +1135 CC genotypes. Significant risk associations were found for ACIle (OR=1.48), GAVal (OR=1.70), GAIle (OR=2.00) haplotypes with GBC cases and GCIle haplotype with female GBC cases (OR=10.37, P=<0.0001). Pair-wise linkage disequilibrium revealed negative associations among variant alleles. On multi-dimensional reduction analysis, a three factor model revealed significant gene-gene interaction for PDGFB +286A>G, PDGFB +1135A>C and HER2 Ile165Val SNPs with GBC. Protein-protein interaction showed significant association of PDGFB and HER2 with the epidermal growth factor receptor signaling pathway.

  13. 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

  14. Stochastic contribution to the growth factor in the LCDM model

    SciTech Connect

    Ribeiro, A. L.B.; Andrade, A. P.A.; Letelier, P. S.

    2009-01-01

    We study the effect of noise on the evolution of the growth factor of density perturbations in the context of the LCDM model. Stochasticity is introduced as a Wiener process amplified by an intensity parameter alpha. By comparing the evolution of deterministic and stochastic cases for different values of alpha we estimate the intensity level necessary to make noise relevant for cosmological tests based on large-scale structure data. Our results indicate that the presence of random forces underlying the fluid description can lead to significant deviations from the nonstochastic solution at late times for alpha>0.001.

  15. Pituitary follicular cells produce basic fibroblast growth factor

    SciTech Connect

    Ferrara, N.; Schweigerer, L.; Neufeld, G.; Mitchell, R.; Gospodarowicz, D.

    1987-08-01

    Cultured monolayers of bovine pituitary follicular cells, which transport ions, contain high amounts of mitogenic activity for endothelial cells which, on the basis of gene expression analysis, heparin-Sepharose elution profile, bioassay, immunoblotting, radioimmunoassay, and radioreceptor assay, has been identified as basic fibroblast growth factor (bFGF). These data indicate that follicular cells may be a major source of bFGF in the pituitary gland. Considering that bFGF has been proposed to play a role in paracrine regulation of pituitary hormone secretion, the data also suggest that these cells may exert important local regulatory functions.

  16. Epidermal growth factor receptors in the canine antrum

    SciTech Connect

    Zimmerman, R.P.; Gates, T.S.; Boehmer, C.G.; Mantyh, P.W.

    1988-11-01

    In this study we localized receptor binding sites for /sup 125/I-human epidermal growth factor (hEGF) in the antrum of the adult canine stomach. High levels of specific /sup 125/I-hEGF binding sites were observed over the mucosa and muscularis mucosa, whereas specific binding sites were not detectable over the submucosa, external circular and longitudinal muscle or myenteric neurons. These results are in agreement with previous studies which indicated that EGF stimulates the proliferation of cultured epithelial cells and inhibits gastric acid secretion. This suggests that EGF may be a useful therapeutic agent in the healing of gastric ulcers.

  17. Therapeutic potential of growth factors in pulmonary emphysematous condition.

    PubMed

    Muyal, Jai Prakash; Muyal, Vandana; Kotnala, Sudhir; Kumar, Dhananjay; Bhardwaj, Harsh

    2013-04-01

    Pulmonary emphysema is a major manifestation of chronic obstructive pulmonary disease (COPD), which is characterized by progressive destruction of alveolar parenchyma with persistent inflammation of the small airways. Such destruction in the distal respiratory tract is irreversible and irreparable. All-trans-retinoic acid was suggested as a novel therapy for regeneration of lost alveoli in emphysema. However, profound discrepancies were evident between studies. At present, no effective therapeutic options are available that allow for the regeneration of lost alveoli in emphysematous human lungs. Recently, some reports on rodent's models have suggested the beneficial effects of various growth factors toward alveolar maintenance and repair processes.

  18. Astrocyte Mitogen Inhibitor Related to Epidermal Growth Factor Receptor

    NASA Astrophysics Data System (ADS)

    Nieto-Sampedro, Manuel

    1988-06-01

    Epidermal growth factor (EGF) is a well-characterized polypeptide hormone with diverse biological activities, including stimulation of astrocyte division. A soluble astrocyte mitogen inhibitor, immunologically related to the EGF receptor, is present in rat brain. Injury to the brain causes a time-dependent reduction in the levels of this inhibitor and the concomitant appearance of EGF receptor on the astrocyte surface. Intracerebral injection of antibody capable of binding the inhibitor caused the appearance of numerous reactive astrocytes. EGF receptor-related inhibitors may play a key role in the control of glial cell division in both normal and injured brain.

  19. Vascular endothelial growth factor: An important molecular target of curcumin.

    PubMed

    Saberi-Karimian, Maryam; Katsiki, Niki; Caraglia, Michele; Boccellino, Mariarosaria; Majeed, Muhammed; Sahebkar, Amirhossein

    2017-08-30

    The discovery of Vascular Endothelial Growth Factor (VEGF), the key modulator of angiogenesis, has triggered intensive research on anti-angiogenic therapeutic modalities. Although several clinical studies have validated anti-VEGF therapeutics, with few of them approved by the U.S. Food and Drug Administration (FDA), anti-angiogenic therapy is still in its infancy. Phytochemicals are compounds that have several metabolic and health benefits. Curcumin, the yellow pigment derived from turmeric (Curcuma longa L.) rhizomes, has a wide range of pharmaceutical properties. It has also been shown to inhibit VEGF by several studies. In this review, we elaborate the effect of curcumin on VEGF and angiogenesis and its therapeutic application.

  20. Fibroblast Growth Factor 21 Analogs for Treating Metabolic Disorders

    PubMed Central

    Zhang, Jun; Li, Yang

    2015-01-01

    Fibroblast growth factor (FGF) 21 is a member of the endocrine FGF subfamily. FGF21 expression is induced under different disease conditions, such as type 2 diabetes, obesity, chronic kidney diseases, and cardiovascular diseases, and it has a broad spectrum of functions in regulating various metabolic parameters. Many different approaches have been pursued targeting FGF21 and its receptors to develop therapeutics for treating type 2 diabetes and other aspects of metabolic conditions. In this article, we summarize some of these key approaches and highlight the potential challenges in the development of these agents. PMID:26594197

  1. [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.

  2. Both epidermal growth factor and insulin-like growth factor receptors are dispensable for structural intestinal adaptation

    PubMed Central

    Sun, Raphael C.; Diaz-Miron, Jose L.; Choi, Pamela M.; Sommovilla, Joshua; Guo, Jun; Erwin, Christopher R.; Warner, Brad W.

    2015-01-01

    Purpose Intestinal adaptation structurally represents increases in crypt depth and villus height in response to small bowel resection (SBR). Previously, we found that neither epidermal growth factor receptor (EGFR) nor insulin-like growth factor 1 receptor (IGF1R) function was individually required for normal adaptation. In this study, we sought to determine the effect of disrupting both EGFR and IGF1R expression on resection-induced adaptation. Methods Intestinal-specific EGFR and IGF1R double knockout mice (EGFR/IGF1R-IKO) (n=6) and wild-type (WT) control mice (n=7) underwent 50% proximal SBR. On postoperative day (POD) 7, structural adaptation was scored by measuring crypt depth and villus height. Rates of crypt cell proliferation, apoptosis, and submucosal capillary density were also compared. Results After 50% SBR, normal adaptation occurred in both WT and EGFR/IGF1R-IKO. Rates of proliferation and apoptosis were no different between the two groups. The angiogenic response was less in the EGFR/IGF1R-IKO compared to WT mice. Conclusion Disrupted expression of EGFR and IGF1R in the intestinal epithelial cells does not affect resection-induced structural adaptation but attenuates angiogenesis after SBR. These findings suggest that villus growth is driven by receptors and pathways that occur outside the epithelial cell component, while angiogenic responses may be influenced by epithelial-endothelial crosstalk. PMID:25818318

  3. Fibroblast growth factor-2 and vascular endothelial growth factor mediated augmentation of angiogenesis and bone formation in vascularized bone allotransplants.

    PubMed

    Larsen, Mikko; Willems, Wouter F; Pelzer, Michael; Friedrich, Patricia F; Dadsetan, Mahrokh; Bishop, Allen T

    2014-05-01

    We previously demonstrated recipient-derived neoangiogenesis to maintain viability of living bone allogeneic transplants without long-term immunosuppression. The effect of cytokine delivery to enhance this process is studied. Vascularized femur transplantation was performed from Dark Agouti to Piebald Virol Glaxo rats. Poly(d,l-lactide-co-glycolide) microspheres loaded with buffer (N = 11), basic fibroblast growth factor (FGF2) (N = 10), vascular endothelial growth factor (VEGF) (N = 11), or both (N = 11) were inserted intramedullarly alongside a recipient-derived arteriovenous bundle. FK-506 was administered for 2 weeks. At 18 weeks, bone blood flow, microangiography, histologic, histomorphometric, and alkaline phosphatase measurements were performed. Bone blood flow was greater in the combined group than control and VEGF groups (P = 0.04). Capillary density was greater in the FGF2 group than in the VEGF and combined groups (P < 0.05). Bone viability, growth, and alkaline phosphatase activity did not vary significantly between groups. Neoangiogenesis in vascularized bone allotransplants is enhanced by angiogenic cytokine delivery, with results using FGF2 that are comparable to isotransplant from previous studies. Further studies are needed to achieve bone formation similar to isotransplants. Copyright © 2013 Wiley Periodicals, Inc.

  4. Epidermal growth factor or transforming growth factor alpha is required for kidney tubulogenesis in matrigel cultures in serum-free medium.

    PubMed Central

    Taub, M; Wang, Y; Szczesny, T M; Kleinman, H K

    1990-01-01

    The ability of matrigel, a reconstituted basement membrane gel, to induce the differentiation of baby mouse kidney cells has been examined in a hormonally defined serum-free medium. Primary cultures of baby mouse kidney cells were observed to form tubules over a time interval of 1-2 weeks in matrigel. Electron microscopic studies showed that tubules with lumens were present, and the tubule morphology was similar to that of the collecting duct. When using matrigel from which the growth factors had been removed, tubule formation no longer occurred, unless the medium was further supplemented with epidermal growth factor (10 ng/ml). Transforming growth factor alpha stimulated tubule formation as effectively as epidermal growth factor, whereas transforming growth factor beta had an inhibitory effect on tubule formation. These data suggest that both an extracellular matrix and specific growth factors may regulate kidney differentiation during development. Images PMID:2339133

  5. Alternative splicing in angiogenesis: the vascular endothelial growth factor paradigm.

    PubMed

    Ladomery, Michael R; Harper, Steven J; Bates, David O

    2007-05-08

    Alternative splicing, first discovered in the 1970s, has emerged as one of the key generators of proteomic diversity. Not surprisingly, alternative splicing is increasingly linked to the etiology of cancer. This is illustrated by vascular endothelial growth factor (VEGF), the dominant angiogenic factor. Recently, an antiangiogenic family of VEGF isoforms was discovered, and termed VEGF(xxx)b. VEGF(xxx)b isoforms arise from an alternative 3' splice site in exon 8, and differ by a mere six amino acids at the C-terminus. These alternative six amino acids radically change the functional properties of VEGF. VEGF(xxx)b isoform expression is regulated in human tissues and development, and disregulated in many pathological states including cancer. Understanding what regulates VEGF(xxx)b alternative splicing, and therefore the balance of pro- and antiangiogenic isoforms is of great importance and will be explored in detail over the next few years.

  6. Transforming growth factor-beta1 to the bone.

    PubMed

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

    2005-10-01

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

  7. Expression of vascular endothelial growth factor in malignant mesothelioma.

    PubMed

    Aoe, Keisuke; Hiraki, Akio; Tanaka, Takehiro; Gemba, Ken-Ichi; Taguchi, Koji; Murakami, Tomoyuki; Sueoka, Naoko; Kamei, Toshiaki; Ueoka, Hiroshi; Sugi, Kazuro; Yoshino, Tadashi; Kishimoto, Takumi

    2006-01-01

    Malignant mesothelioma is the most common primary pleural neoplasm. Angiogenesis is an important component of a variety of pathological processes, including carcinogenesis and tumor metastases. Vascular endothelial growth factor (VEGF) is the most potent known endothelial, cell specific mitogen. The authors assessed the relation between VEGF expression and clinicopathological variables or overall survival, in malignant mesothelioma. We studied 37 patients with malignant pleural mesothelioma and found that 36 out of 37 (97.3%) malignant mesothelioma samples were stained positively for VEGF. An increased expression of VEGF was observed in the epithelioid type compared with the other histological types of malignant mesothelioma, including the biphasic and sarcomatoid types. No statistically significant association was observed between VEGF expression and gender, age, or clinical stage. Furthermore, the expression of VEGF did not impact on the survival of patients with malignant mesothelioma. Although VEGF expression might be important for tumor development and maintenance, it was not identified as a prognostic factor in malignant mesothelioma.

  8. The growth factor myostatin, a key regulator in skeletal muscle growth and homeostasis.

    PubMed

    Matsakas, A; Diel, P

    2005-03-01

    Skeletal muscle possesses the ability to both respond and adapt to changing environmental stimuli, leading to a set of metabolic and morphological adaptations, which allow it to better meet the energy demands of sustained physical activity. Great progress has been achieved over the past years by means of innovative molecular techniques, which has led to the discovery of new growth factors and the identification of molecular mechanisms involved in the regulation of muscle development. These findings provide new starting points to understand the molecular mechanisms involved in the adaptation of skeletal muscle to exercise training. One of these new identified growth factors is myostatin, a member of the transforming growth factor-beta family of proteins that has been demonstrated to play a fundamental role in the regulation of skeletal muscle growth during embryogenesis. Blocking of the myostatin signalling transduction pathway by specific inhibitors and genetic manipulations has been shown to result in a dramatic increase of skeletal muscle mass. This review focuses on the importance of myostatin in mediating skeletal muscle homeostasis in response to training as well as during the progress of myogenic disease, like atrophy or dystrophy. Manipulations of myostatin signalling may be useful for agriculture applications, treatment of muscle diseases, inhibition of muscle atrophy and last but not least as life style drugs in antiaging therapies or manipulations of the muscle to fat ratio. Drugs with the ability to modulate myostatin signalling may have the potential to enhance physical performance in athletes and therefore they probably represent a new class of doping substances.

  9. Extracellular matrix-inspired growth factor delivery systems for bone regeneration.

    PubMed

    Martino, Mikaël M; Briquez, Priscilla S; Maruyama, Kenta; Hubbell, Jeffrey A

    2015-11-01

    Growth factors are very promising molecules to enhance bone regeneration. However, their translation to clinical use has been seriously limited, facing issues related to safety and cost-effectiveness. These problems derive from the vastly supra-physiological doses of growth factor used without optimized delivery systems. Therefore, these issues have motivated the development of new delivery systems allowing better control of the spatiotemporal release and signaling of growth factors. Because the extracellular matrix (ECM) naturally plays a fundamental role in coordinating growth factor activity in vivo, a number of novel delivery systems have been inspired by the growth factor regulatory function of the ECM. After introducing the role of growth factors during the bone regeneration process, this review exposes different issues that growth factor-based therapies have encountered in the clinic and highlights recent delivery approaches based on the natural interaction between growth factor and the ECM. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Extracellular matrix-inspired growth factor delivery systems for bone regeneration

    SciTech Connect

    Martino, Mikaël M.; Briquez, Priscilla S.; Maruyama, Kenta; Hubbell, Jeffrey A.

    2015-04-17

    Growth factors are very promising molecules to enhance bone regeneration. However, their translation to clinical use has been seriously limited, facing issues related to safety and cost-effectiveness. These problems derive from the vastly supra-physiological doses of growth factor used without optimized delivery systems. Therefore, these issues have motivated the development of new delivery systems allowing better control of the spatio-temporal release and signaling of growth factors. Because the extracellular matrix (ECM) naturally plays a fundamental role in coordinating growth factor activity in vivo, a number of novel delivery systems have been inspired by the growth factor regulatory function of the ECM. After introducing the role of growth factors during the bone regeneration process, this review exposes different issues that growth factor-based therapies have encountered in the clinic and highlights recent delivery approaches based on the natural interaction between growth factor and the ECM.

  11. Multiple growth factors, cytokines, and neurotrophins rescue photoreceptors from the damaging effects of constant light.

    PubMed Central

    LaVail, M M; Unoki, K; Yasumura, D; Matthes, M T; Yancopoulos, G D; Steinberg, R H

    1992-01-01

    Recent demonstrations of survival-promoting activity by neurotrophic agents in diverse neuronal systems have raised the possibility of pharmacological therapy for inherited and degenerative disorders of the central nervous system. We have shown previously that, in the retina, basic fibroblast growth factor delays photoreceptor degeneration in Royal College of Surgeons rats with inherited retinal dystrophy and that the growth factor reduces or prevents the rapid photoreceptor degeneration produced by constant light in the rat. This light-damage model now provides an efficient way to assess quantitatively the survival-promoting activity in vivo of a number of growth factors and other molecules. We report here that photoreceptors can be significantly protected from the damaging effects of light by intravitreal injection of eight different growth factors, cytokines, and neurotrophins that typically act through several distinct receptor families. In addition to basic fibroblast growth factor, those factors providing a high degree of photoreceptor rescue include brain-derived neurotrophic factor, ciliary neurotrophic factor, interleukin 1 beta, and acidic fibroblast growth factor; those with less activity include neurotrophin 3, insulin-like growth factor II, and tumor necrosis factor alpha; those showing little or no protective effect are nerve growth factor, epidermal growth factor, platelet-derived growth factor, insulin, insulin-like growth factor I, heparin, and laminin. Although we used at least one relatively high concentration of each agent (the highest available), it is still possible that other concentrations or factor combinations might be more protective. Injecting heparin along with acidic fibroblast growth factor or basic fibroblast growth factor further enhanced the degree of photoreceptor survival and also suppressed the increased incidence of macrophages produced by either factor, especially basic fibroblast growth factor. These results now provide the

  12. Promoted growth of murine hair follicles through controlled release of vascular endothelial growth factor.

    PubMed

    Ozeki, Makoto; Tabata, Yasuhiko

    2002-06-01

    The objective of this study is to investigate whether or not the controlled release of vascular endothelial growth factor (VEGF) is effective in promoting the hair follicle growth of mice in second anagen of hair cycle. VEGF was incorporated into a biodegradable collagen hydrogel for its controlled release. Following implantation of the collagen hydrogel incorporating 0 or 2 microg of VEGF and injection of 0 or 2 microg of VEGF in the solution form into the back subcutis of mice, the hair follicle growth was evaluated photometrically and histologically in terms of the skin color of reverse side of the implanted or injected site, the skin thickness, and the area occupied by hair follicle tissue. Ten days later, the skin color of mice implanted with the collagen hydrogel incorporating 2 microg of VEGF was significantly darker than that injected with 2 pg of VEGF. The collagen hydrogel incorporating VEGF increased the hair follicle area at the implanted site to a significantly greater extent than other agents while significant angiogenetic effect in the skin tissue was observed. VEGF-free, empty collagen hydrogels did not affect the skin darkness, hair follicle growth, and the angiogenesis. Moreover, the hair shaft length was significantly elongated by the collagen hydrogel incorporating VEGF, in marked contrast to other agents. Immunohistolchemicalstaining with proliferating cell nuclear antigen revealed that the collagen hydrogel incorporating VEGF promoted the proliferation of cells around the hair follicle more frequently than free VEGF. We concluded that the controlled release of VEGF more positively acted on the hair growth cycle of mice for hair growth than the injection of free VEGF.

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

    PubMed Central

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

    2006-01-01

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

  14. Vascular endothelial growth factor receptor 3 directly regulates murine neurogenesis

    PubMed Central

    Calvo, Charles-Félix; Fontaine, Romain H.; Soueid, Jihane; Tammela, Tuomas; Makinen, Taija; Alfaro-Cervello, Clara; Bonnaud, Fabien; Miguez, Andres; Benhaim, Lucile; Xu, Yunling; Barallobre, Maria-José; Moutkine, Imane; Lyytikkä, Johannes; Tatlisumak, Turgut; Pytowski, Bronislaw; Zalc, Bernard; Richardson, William; Kessaris, Nicoletta; Garcia-Verdugo, Jose Manuel; Alitalo, Kari; Eichmann, Anne; Thomas, Jean-Léon

    2011-01-01

    Neural stem cells (NSCs) are slowly dividing astrocytes that are intimately associated with capillary endothelial cells in the subventricular zone (SVZ) of the brain. Functionally, members of the vascular endothelial growth factor (VEGF) family can stimulate neurogenesis as well as angiogenesis, but it has been unclear whether they act directly via VEGF receptors (VEGFRs) expressed by neural cells, or indirectly via the release of growth factors from angiogenic capillaries. Here, we show that VEGFR-3, a receptor required for lymphangiogenesis, is expressed by NSCs and is directly required for neurogenesis. Vegfr3:YFP reporter mice show VEGFR-3 expression in multipotent NSCs, which are capable of self-renewal and are activated by the VEGFR-3 ligand VEGF-C in vitro. Overexpression of VEGF-C stimulates VEGFR-3-expressing NSCs and neurogenesis in the SVZ without affecting angiogenesis. Conversely, conditional deletion of Vegfr3 in neural cells, inducible deletion in subventricular astrocytes, and blocking of VEGFR-3 signaling with antibodies reduce SVZ neurogenesis. Therefore, VEGF-C/VEGFR-3 signaling acts directly on NSCs and regulates adult neurogenesis, opening potential approaches for treatment of neurodegenerative diseases. PMID:21498572

  15. Serum concentrations of basic fibroblast growth factor in collagen diseases.

    PubMed

    Kadono, T; Kikuchi, K; Kubo, M; Fujimoto, M; Tamaki, K

    1996-09-01

    Basic fibroblast growth factor (bFGF), a cytoplasmic polypeptide growth regulator that induces endothelial cell and fibroblast proliferation, is produced by endothelial cells and skeletal muscle. We hypothesized that this factor is involved in fibrotic changes in muscle and skin in collagen diseases. The serum level of bFGF was measured in 74 patients with systemic sclerosis, 12 with systemic lupus erythematosus, 33 with dermatomyositis, 13 with Raynaud's disease, and 20 control subjects. bFGF was undetectable in the serum of normal persons, but detectable levels were found in 31 of 74 patients with systemic sclerosis and 7 of 33 patients with dermatomyositis. Elevated serum bFGF level was correlated with an elevated plasma endothelin level and anticentromere antibody in patients with systemic sclerosis. An elevated serum bFGF level correlated with lung fibrosis and an elevated creatine kinase level in the patients with dermatomyositis. Measurement of the serum bFGF level may be useful to detect vascular damage in patients with systemic sclerosis and muscule fibrosis in patients with dermatomyositis.

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

    PubMed Central

    Gabriella, Casalena; Ilse, Daehn; Erwin, Bottinger

    2012-01-01

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

  17. Transgenic Soybean Production of Bioactive Human Epidermal Growth Factor (EGF)

    PubMed Central

    He, Yonghua; Schmidt, Monica A.; Erwin, Christopher; Guo, Jun; Sun, Raphael; Pendarvis, Ken; Warner, Brad W.; Herman, Eliot M.

    2016-01-01

    Necrotizing enterocolitis (NEC) is a devastating condition of premature infants that results from the gut microbiome invading immature intestinal tissues. This results in a life-threatening disease that is frequently treated with the surgical removal of diseased and dead tissues. Epidermal growth factor (EGF), typically found in bodily fluids, such as amniotic fluid, salvia and mother’s breast milk, is an intestinotrophic growth factor and may reduce the onset of NEC in premature infants. We have produced human EGF in soybean seeds to levels biologically relevant and demonstrated its comparable activity to commercially available EGF. Transgenic soybean seeds expressing a seed-specific codon optimized gene encoding of the human EGF protein with an added ER signal tag at the N’ terminal were produced. Seven independent lines were grown to homozygous and found to accumulate a range of 6.7 +/- 3.1 to 129.0 +/- 36.7 μg EGF/g of dry soybean seed. Proteomic and immunoblot analysis indicates that the inserted EGF is the same as the human EGF protein. Phosphorylation and immunohistochemical assays on the EGF receptor in HeLa cells indicate the EGF protein produced in soybean seed is bioactive and comparable to commercially available human EGF. This work demonstrates the feasibility of using soybean seeds as a biofactory to produce therapeutic agents in a soymilk delivery platform. PMID:27314851

  18. Discovery of SNPs in the swine nerve growth factor gene.

    PubMed

    Chung, H Y; Kim, J Y

    2010-10-01

    This study was aimed to search genetic variants for the swine nerve growth factor gene that associated with regulation of proliferation and differentiation of nervous systems. The swine nerve growth factor gene was screened with 5 primer sets for random populations of crossbred pigs born 2005-2007 at National Institute of Animal Science (NIAS). To verify genetic variants of miniature pigs, a total of 288,000 BAC clones generated from NIAS in 2007 were used. The selection of primer sequences was based on sequences of the swine in GenBank (L31898), and genetic variants have been discovered in the crossbred population positioned at 381 (A/C), 412 (C/T), 422 (G/A), 468 (G/C), 496 (A/G), 538 (T/C), 540 (G/A), and 547 (A/G) showing substitutions of amino acids. The identified sequences of miniature pigs including SNPs were submitted into GenBank with an accession number (GQ423508). The sequence alignment conducted to compare genetic distances between species, revealing not many high similarities between swine and human as approximately 0.89 that was a little bit high value than expected. Consequently, we suggest that the identified SNPs of the swine NGF gene may be used in the future to identify genetic markers in coding regions, regarding explanations of phenotypic variations.

  19. Hepatocyte growth factor-modulated rat Leydig cell functions.

    PubMed

    Del Bravo, Jessica; Catizone, Angela; Ricci, Giulia; Galdieri, Michela

    2007-01-01

    Hepatocyte growth factor (HGF) regulates many cellular functions acting through c-Met, its specific tyrosine kinase receptor. We previously reported that in prepuberal rats HGF is secreted by the peritubular myoid cells during the entire postnatal testicular development and by the Sertoli cells only at puberty. We have also demonstrated that germ cells at different stages of development express c-Met and that HGF modulates germ cell proliferation and apoptosis. In the present article, we extend our study to the interstitial compartment of the testis and demonstrate that the c-Met protein is present on Leydig cells. The receptor is functionally active as demonstrated by the detected effects of HGF. We report in this article that HGF significantly increases the amount of testosterone secreted by the Leydig cells and decreases the number of Leydig cells undergoing apoptosis. The antiapoptotic effect of HGF is mediated by caspase-3 activity because the amount of the active fragment of the enzyme is decreased in Leydig cells cultured in the presence of HGF. However, treatment with the growth factor does not modify the expression levels of caspase-3 mRNA. These data indicate that HGF regulates the functional activities of Leydig cells. Interestingly, the steroidogenetic activity of the cells is increased by HGF in cultured explants of testicular tissues as well as the antiapoptotic effect of HGF. Therefore, our data indicate that HGF has a crucial role in the regulation of male fertility.

  20. Polychlorinated Biphenyls Disrupt Hepatic Epidermal Growth Factor Receptor Signaling.

    PubMed

    Hardesty, Josiah E; Wahlang, Banrida; Falkner, K Cameron; Clair, Heather B; Clark, Barbara J; Ceresa, Brian P; Prough, Russell A; Cave, Matthew C

    2016-07-26

    1. Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that disrupt hepatic xenobiotic and intermediary metabolism, leading to metabolic syndrome and nonalcoholic steatohepatitis (NASH). 2. Since phenobarbital indirectly activates Constitutive Androstane Receptor (CAR) by antagonizing growth factor binding to the epidermal growth factor receptor (EGFR), we hypothesised that PCBs may also diminish EGFR signaling. 3. The effects of the PCB mixture Aroclor 1260 on the protein phosphorylation cascade triggered by EGFR activation were determined in murine (in vitro and in vivo) and human models (in vitro). EGFR tyrosine residue phosphorylation was decreased by PCBs in all models tested. 4. The IC50 values for Aroclor 1260 concentrations that decreased Y1173 phosphorylation of EGFR were similar in murine AML-12 and human HepG2 cells (∼2-4 μg/mL). Both dioxin and non-dioxin-like PCB congeners decreased EGFR phosphorylation in cell culture. 5. PCB treatment reduced phosphorylation of downstream EGFR effectors including Akt and mTOR, as well as other phosphoprotein targets including STAT3 and c-RAF in vivo. 6. PCBs diminish EGFR signaling in human and murine hepatocyte models and may dysregulate critical phosphoprotein regulators of energy metabolism and nutrition, providing a new mechanism of action in environmental diseases.

  1. Insulin-like growth factors and fish reproduction.

    PubMed

    Reinecke, Manfred

    2010-04-01

    Knowledge of fish reproduction is of high relevance to basic fish biology and comparative evolution. Furthermore, fish are excellent biomedical models, and the impact of aquaculture on worldwide food production is steadily increasing. Consequently, research on fish reproduction and the potential modes of its manipulation has become more and more important. Reproduction in fish is regulated by the integration of endogenous neuroendocrine (gonadotropins), endocrine, and autocrine/paracrine signals with exogenous (environmental) factors. The main endocrine regulators of gonadal sex differentiation and function are steroid hormones. However, recent studies suggest that other hormones are also involved. Most prominent among these hormones are the insulin-like growth factors (Igfs), i.e., Igf1, Igf2, and, most recently, Igf3. Thus, the present review deals with the expression patterns and potential physiological functions of Igf1 and Igf2 in male and female gonads. It further considers the potential involvement of growth hormone (Gh) and balances the reasons for endocrine vs. autocrine/paracrine action of the Igfs on the gonads of fish. Finally, this review discusses the early and late development of gonadal Igf1 and Igf2 and whether they are targets of endocrine-disrupting compounds. Future topics for novel research investigation on Igfs and fish reproduction are presented.

  2. Understanding Cytokine and Growth Factor Receptor Activation Mechanisms

    PubMed Central

    Atanasova, Mariya; Whitty, Adrian

    2012-01-01

    Our understanding of the detailed mechanism of action of cytokine and growth factor receptors – and particularly our quantitative understanding of the link between structure, mechanism and function – lags significantly behind our knowledge of comparable functional protein classes such as enzymes, G protein-coupled receptors, and ion channels. In particular, it remains controversial whether such receptors are activated by a mechanism of ligand-induced oligomerization, versus a mechanism in which the ligand binds to a pre-associated receptor dimer or oligomer that becomes activated through subsequent conformational rearrangement. A major limitation to progress has been the relative paucity of methods for performing quantitative mechanistic experiments on unmodified receptors expressed at endogenous levels on live cells. In this article we review the current state of knowledge on the activation mechanisms of cytokine and growth factor receptors, critically evaluate the evidence for and against the different proposed mechanisms, and highlight other key questions that remain unanswered. New approaches and techniques have led to rapid recent progress in this area, and the field is poised for major advances in the coming years, which promises to revolutionize our understanding of this large and biologically and medically important class of receptors. PMID:23046381

  3. Upregulation of epidermal growth factor receptor 4 in oral leukoplakia

    PubMed Central

    Kobayashi, Hiroshi; Kumagai, Kenichi; Gotoh, Akito; Eguchi, Takanori; Yamada, Hiroyuki; Hamada, Yoshiki; Suzuki, Satsuki; Suzuki, Ryuji

    2013-01-01

    In the present study, we investigate the expression profile of the epidermal growth factor receptor family, which comprises EGFR/ErbB1, HER2/ErbB2, HER3/ErbB3 and HER4/ErbB4 in oral leukoplakia (LP). The expression of four epidermal growth factor receptor (EGFR) family genes and their ligands were measured in LP tissues from 14 patients and compared with levels in 10 patients with oral lichen planus (OLP) and normal oral mucosa (NOM) from 14 healthy donors by real-time polymerase chain reaction (PCR) and immunohistochemistry. Synchronous mRNA coexpression of ErbB1, ErbB2, ErbB3 and ErbB4 was detected in LP lesions. Out of the receptors, only ErbB4 mRNA and protein was more highly expressed in LP compared with NOM tissues. These were strongly expressed by epithelial keratinocytes in LP lesions, as shown by immunohistochemistry. Regarding the ligands, the mRNA of Neuregulin2 and 4 were more highly expressed in OLP compared with NOM tissues. Therefore, enhanced ErbB4 on the keratinocytes and synchronous modulation of EGFR family genes may contribute to the pathogenesis and carcinogenesis of LP. PMID:23492901

  4. Injectable fibroblast growth factor-2 coacervate for persistent angiogenesis

    PubMed Central

    Chu, Hunghao; Gao, Jin; Chen, Chien-Wen; Huard, Johnny; Wang, Yadong

    2011-01-01

    Enhancing the maturity of the newly formed blood vessels is critical for the success of therapeutic angiogenesis. The maturation of vasculature relies on active participation of mural cells to stabilize endothelium and a basal level of relevant growth factors. We set out to design and successfully achieved robust angiogenesis using an injectable polyvalent coacervate of a polycation, heparin, and fibroblast growth factor-2 (FGF2). FGF2 was loaded into the coacervate at nearly 100% efficiency. In vitro assays demonstrated that the matrix protected FGF2 from proteolytic degradations. FGF2 released from the coacervate was more effective in the differentiation of endothelial cells and chemotaxis of pericytes than free FGF2. One injection of 500 ng of FGF2 in the coacervate elicited comprehensive angiogenesis in vivo. The number of endothelial and mural cells increased significantly, and the local tissue contained more and larger blood vessels with increased circulation. Mural cells actively participated during the whole angiogenic process: Within 7 d of the injection, pericytes were recruited to close proximity of the endothelial cells. Mature vasculature stabilized by vascular smooth muscle cells persisted till at least 4 wk. On the other hand, bolus injection of an identical amount of free FGF2 induced weak angiogenic responses. These results demonstrate the potential of polyvalent coacervate as a new controlled delivery platform. PMID:21808045

  5. Endothelin-1 induces connective tissue growth factor expression in cardiomyocytes.

    PubMed

    Recchia, Anna Grazia; Filice, Elisabetta; Pellegrino, Daniela; Dobrina, Aldo; Cerra, Maria Carmela; Maggiolini, Marcello

    2009-03-01

    Endothelin (ET)-1 is a vasoconstrictor involved in cardiovascular diseases. Connective tissue growth factor/CCN2 (CTGF) is a fibrotic mediator overexpressed in human atherosclerotic lesions, myocardial infarction, and hypertension. In different cell types CTGF regulates cell proliferation/apoptosis, migration, and extracellular matrix (ECM) accumulation and plays important roles in angiogenesis, chondrogenesis, osteogenesis, tissue repair, cancer and fibrosis. In the present study, we investigated the ET-1 signaling which triggers CTGF expression in cultured adult mouse atrial-muscle HL-1 cells used as a model system. ET-1 activated the CTGF promoter and induced CTGF expression at both mRNA and protein levels. Real-time PCR analysis revealed CTGF induction also in isolated rat heart preparations perfused with ET-1. Several intracellular signals elicited by ET-1 via ET receptors and even Epidermal Growth Factor Receptor (EGFR) contributed to the up-regulation of CTGF, including ERK activation and induction of the AP-1 components c-fos and c-jun, as also evaluated by ChIP analysis. Moreover, in cells treated with ET-1 the expression of ECM component decorin was abolished by CTGF silencing, indicating that CTGF is involved in ET-1 induced ECM accumulation not only in a direct manner but also through downstream effectors. Collectively, our data indicate that CTGF could be a mediator of the profibrotic effects of ET-1 in cardiomyocytes. CTGF inhibitors should be considered in setting a comprehensive pharmacological approach towards ET-1 induced cardiovascular diseases.

  6. Fibroblast growth factor-2 promotes in vitro mitral valve interstitial cell repair through transforming growth factor-β/Smad signaling.

    PubMed

    Han, Li; Gotlieb, Avrum I

    2011-01-01

    Transforming growth factor (TGF)-β and fibroblast growth factor (FGF)-2 both promote repair in valve interstitial cell (VIC) injury models; however, the relationship between TGF-β and FGF-2 in wound repair are not well understood. VIC confluent monolayers were wounded by mechanical injury and incubated separately or in combination with FGF-2, neutralizing antibody to FGF-2, neutralizing antibody to TGF-β, and betaglycan antibody for 24 hours after wounding. Phosphorylated Smad2/3 (pSmad2/3) was localized at the wound edge (WE) and at the monolayer away from the WE. Down-regulation of pSmad2/3 protein expression via small-interfering RNA transfection was performed. The extent of wound closure was monitored for up to 96 hours. FGF-2 incubation resulted in a significant increase in nuclear pSmad2/3 staining at the WE. Neutralizing antibody to TGF-β alone or with FGF-2 present resulted in a similar significant decrease in pSmad2/3. Neutralizing antibody to FGF-2 alone or with FGF-2 present showed a similar significant decrease in pSmad2/3; however, significantly more staining was observed than treatment with neutralizing antibody to TGF-β. Incubation with betaglycan antibody inhibited FGF-2-mediated pSmad2/3 signaling. Wound closure corresponded with pSmad2/3 staining at the WE. Down-regulation of pSmad2/3 via small-interfering RNA transfection significantly reduced the extent to which FGF-2 promoted wound closure. Fibroblast growth factor-2 promotes in vitro VIC wound repair, at least in part, through the TGF-β/Smad2/3 signaling pathway.

  7. Oestrogens, via transforming growth factor alpha, modulate basic fibroblast growth factor synthesis in hypothalamic astrocytes: in vitro observations.

    PubMed

    Galbiati, M; Martini, L; Melcangi, R C

    2002-10-01

    The data presented here show that, in cultures of type 1 astrocytes obtained from the hypothalamus of neonatal female rat, 17beta-oestradiol is able to increase both the mRNA and the protein levels of basic fibroblast growth factor (bFGF). In particular, after 24 h of exposure to 17beta-oestradiol (10(-9) and 10(-10) m), an increase of messenger levels of bFGF appears in hypothalamic type 1 astrocytes. Similarly, an induction of bFGF protein is also evident at this time of exposure. The effect on the mRNA and protein levels of bFGF is blocked by the presence in the medium of an antibody raised against the transforming growth factor alpha (TGFalpha) receptor. This observation indicates that, TGFalpha, whose synthesis is modulated by oestrogens in hypothalamic astrocytes and which is able to increase, both the mRNA and the protein levels of bFGF in our experimental model, may act as the mediator of the oestrogenic induction of bFGF. Hypothalamic astrocytes, together with hypothalamic neurones synthesizing and secreting luteinizing hormone-releasing hormone (LHRH), form the LHRH network in conjunction with other neuronal systems. Gonadal steroids in general, and oestrogens in particular, play an important role in the control of the activity of this network. In addition, bFGF and TGFalpha, two growth factors released from astrocytes, are able to influence the activity of LHRH neurones. The present observations suggest that oestrogens may also act on LHRH neurones in an indirect fashion (i.e. by modulating the expression of bFGF and TGFalpha in glial cells).

  8. Synergistic induction of neurite outgrowth by nerve growth factor or epidermal growth factor and interleukin-6 in PC12 cells.

    PubMed

    Wu, Y Y; Bradshaw, R A

    1996-05-31

    Native PC12 cells respond differentially to nerve growth factor (NGF) but not interleukin-6 (IL-6); PC12-E2 cells, a stable variant, respond to both stimuli (and more rapidly to NGF). Neither responds to epidermal growth factor (EGF). NGF primarily induces the RAS/extracellular signal-regulated kinase (ERK) pathway and IL-6 activates a JAK (Janus tyrosine kinase)/STAT (signal transducers and activators of transcription) response. EGF also stimulates RAS/ERK but in a transient manner. When either cell type is treated with combinations of NGF, EGF, and IL-6, at concentrations that produce modest or no response, a substantial augmentation of neurite outgrowth is observed. With PC12-E2 cells, a subthreshold concentration of IL-6 increases NGF response by approximately 2-3-fold after 1-2 days; the increase with EGF is more pronounced. Native PC12 cells show even greater synergistic effects with NGF and IL-6. The most dramatic effect was observed with low levels of EGF, where IL-6 increased the percentage of responsive cells from zero to approximately 60% after 3 days. In addition, two neural-specific transcripts, GAP-43 and SCG-10, are synergistically increased by the combinations of growth factors. Importantly, IL-6 does not enhance ERK phosphorylation in the presence of either NGF or EGF. In contrast, NGF and EGF, in the presence or absence of IL-6, cause mobility shifts of Stat3 that are consistent with serine phosphorylations. Although these modifications do not lead to activation and translocation by themselves, in the presence of the tyrosine phosphorylation induced by IL-6, they may play a role in the synergistic responses. These observations suggest a differentially regulated two-stage mechanism for the differentiative response of PC12 cells to NGF.

  9. Hepatocyte growth factor, a biomarker of macroangiopathy in diabetes mellitus

    PubMed Central

    Konya, Hiroyuki; Miuchi, Masayuki; Satani, Kahori; Matsutani, Satoshi; Tsunoda, Taku; Yano, Yuzo; Katsuno, Tomoyuki; Hamaguchi, Tomoya; Miyagawa, Jun-Ichiro; Namba, Mitsuyoshi

    2014-01-01

    Atherosclerotic involvements are an essential causal element of prospect in diabetes mellitus (DM), with carotid atherosclerosis (CA) being a common risk-factor for prospective crisis of coronary artery diseases (CAD) and/or cerebral infarction (CI) in DM subjects. From another point of view, several reports have supplied augmenting proof that hepatocyte growth factor (HGF) has a physiopathological part in DM involvements. HGF has been a mesenchymal-derived polyphenic factor which modulates development, motion, and morphosis of diverse cells, and has been regarded as a humor intermediator of epithelial-mesenchymal interplays. The serum concentrations of HGF have been elevated in subjects with CAD and CI, especially during the acute phase of both disturbances. In our study with 89 type 2 DM patients, the association between serum concentrations of HGF and risk-factors for macrovascular complications inclusive of CA were examined. The average of serum HGF levels in the subjects was more elevated than the reference interval. The serum HGF concentrations associated positively with both intimal-media thickness (IMT) (r = 0.24, P = 0.0248) and plaque score (r = 0.27, P = 0.0126), indicating a relationship between the elevated HGF concentrations and advancement of CA involvements. Multivariate statistical analysis accentuated that serum concentrations of HGF would be associated independently with IMT (standardized = 0.28, P = 0.0499). The review indicates what is presently known regarding serum HGF might be a new and meaningful biomarker of macroangiopathy in DM subjects. PMID:25317245

  10. Water Activity Limits the Hygroscopic Growth Factor of Organic Aerosols

    NASA Astrophysics Data System (ADS)

    Rodriguez, L. I.; Cabrera, J. A.; Golden, D.; Tabazadeh, A.

    2007-12-01

    In this work we study the hygroscopic behavior of organic aerosols, which has important implications for Earth's climate. The hygroscopic growth factor (HGF) is defined as the ratio of the diameter of a spherical particle when it is exposed to dry conditions to that at humid conditions. We present a new formulation to express the HGF of an aerosol particle as a function of water activity (aw) in the aqueous phase. This new formulation matches reported HGFs for common inorganic salts and water-miscible organic particles that are known to deliquesce into aqueous drops at high relative humidities (RH). Many studies use tandem differential mobility analyzers (TDMA) to determine the HGF of organic aerosols. For example, Brooks et al. used a TDMA to measure a HGF of 1.2 for 2 μm phthalic acid (PA) particles at 90% RH (aw= 0.9). However, water activity limits the growth of a particle that can be attributed to water uptake. We have assembled a vapor pressure apparatus to measure aw of aqueous solutions at room temperature. Measured water activities for PA, used in our growth formulation, yield a HGF of ~ 1.0005 for 2 μm PA particles at 90% RH. Comparing our results against Brooks et al. suggests that TDMA experiments may grossly overestimate the HGF of PA particles since water activity limits this growth to below 1.0005. Alternatively, we suggest that the adsorption of a negligible mass of water by a highly porous PA particle can lead to an apparent growth in particle size by changing its morphology. Other studies also use TDMAs to measure HGFs of secondary organic aerosols (SOAs). HGFs reported for SOAs are very similar to PA, suggesting that the observed growth may be due to morphological changes in particle size rather than water uptake as commonly assumed. We built a smog chamber where an organic precursor, such as d-limonene, reacts with nitrogen oxides under UV radiation to produce SOAs. We compare the HGFs for SOAs obtained with our method to those obtained with

  11. Rapid population growth and environmental degradation: ultimate versus proximate factors.

    PubMed

    Shaw, R P

    1989-01-01

    This philosophical review of 2 arguments about responsibility for and solutions to environmental degradation concludes that both sides are correct: the ultimate and the proximal causes. Ultimate causes of pollution are defined as the technology responsible for a given type of pollution, such as burning fossil fuel; proximate causes are defined as situation-specific factors confounding the problem, such as population density or rate of growth. Commoner and others argue that developed countries with low or negative population growth rates are responsible for 80% of world pollution, primarily in polluting technologies such as automobiles, power generation, plastics, pesticides, toxic wastes, garbage, warfaring, and nuclear weapons wastes. Distortionary policies also contribute; examples are agricultural trade protection, land mismanagement, urban bias in expenditures, and institutional rigidity., Poor nations are responsible for very little pollution because poverty allows little waste or expenditures for polluting, synthetic technologies. The proximal causes of pollution include numbers and rate of growth of populations responsible for the pollution. Since change in the ultimate cause of pollution remains out of reach, altering the numbers of polluters can make a difference. Predictions are made for proportions of the world's total waste production, assuming current 1.6 tons/capita for developed countries and 0.17 tons/capita for developing countries. If developing countries grow at current rates and become more wealthy, they will be emitting half the world's waste by 2025. ON the other hand, unsustainable population growth goes along with inadequate investment in human capital: education, health, employment, infrastructure. The solution is to improve farming technologies in the 117 non-self-sufficient countries, fund development in the most unsustainable enclaves of growing countries, break institutionalized socio-political rigidity in these enclaves, and focus on

  12. Development of the epidermal growth factor receptor inhibitor OSI-774.

    PubMed

    Grünwald, Viktor; Hidalgo, Manuel

    2003-06-01

    The epidermal growth factor receptor (EGFR) is a transmembrane receptor involved in the regulation of a complex array of essential biological processes such as cell proliferation and survival. Dysregulation of the EGFR signaling network has been frequently reported in multiple human cancers and has been associated with the processes of tumor development, growth, proliferation, metastasis, and angiogenesis. Inhibition of the EGFR was associated with antitumor effects in preclinical models. On the basis of these data, therapeutics targeting the EGFR were explored in clinical trials. OSI-774 is a small-molecule selective inhibitor of the EGFR tyrosine kinase. In preclinical studies, OSI-774 inhibited the phosphorylation of the EGFR in a dose-dependent and concentration-dependent manner resulting in cell cycle arrest and induction of apoptosis. In in vivo studies, this agent caused tumor growth inhibition and showed synergistic effects when combined with conventional chemotherapy. Subsequent single-agent phase I studies and phase I studies in combination with chemotherapy showed that the agent has a good safety profile and induced tumor growth inhibition in a substantial number of patients with a variety of different solid tumors. Preliminary reports from phase II studies confirmed the excellent tolerability of OSI-774 and showed encouraging preliminary activity. Phase III studies have either been completed or are ongoing in several tumor types such as lung cancer and pancreatic cancer. In summary, OSI-774 is a novel inhibitor of the EGFR tyrosine kinase that has shown promising activity in initial studies and is currently undergoing full development as an anticancer drug.

  13. Systemic inflammation, growth factors, and linear growth in the setting of infection and malnutrition.

    PubMed

    DeBoer, Mark D; Scharf, Rebecca J; Leite, Alvaro M; Férrer, Alessandra; Havt, Alexandre; Pinkerton, Relana; Lima, Aldo A; Guerrant, Richard L

    2017-01-01

    Deficits in weight gain and linear growth are seen frequently among children in areas where malnutrition and recurrent infections are common. Although both inflammation and malnutrition can result in growth hormone (GH) resistance, the interrelationships of infection, inflammation, and growth deficits in developing areas remain unclear. The aim of this study was to evaluate relationships between low levels of systemic inflammation, growth factors, and anthropometry in a case-control cohort of underweight and normal weight children in northern Brazil. We evaluated data from 147 children ages 6 to 24 mo evaluated in the MAL-ED (Interactions of Malnutrition and Enteric Disease) case-control study following recruitment from a nutrition clinic for impoverished families in Fortaleza, Brazil. We used nonparametric tests and linear regression to evaluate relationships between current symptoms of infections (assessed by questionnaire), systemic inflammation (assessed by high-sensitivity C-reactive protein [hsCRP]), the GH insulin-like growth factor-1 (IGF-1) axis, and measures of anthropometry. All models were adjusted for age and sex. Children with recent symptoms of diarrhea, cough, and fever (compared with those without symptoms) had higher hsCRP levels; those with recent diarrhea and fever also had lower IGF-1 and higher GH levels. Stool myeloperoxidase was positively associated with serum hsCRP. hsCRP was in turn positively associated with GH and negatively associated with IGF-1 and IGF-binding protein-3 (IGFBP-3), suggesting a state of GH resistance. After adjustment for hsCRP, IGF-1 and IGFBP-3 were positively and GH was negatively associated with Z scores for height and weight. Infection and inflammation were linked to evidence of GH resistance, whereas levels of GH, IGF-1, and IGFBP-3 were associated with growth indices independent of hsCRP. These data implicate complex interrelationships between infection, nutritional status, GH axis, and linear growth in

  14. Epidermal homeostasis: the role of the growth hormone and insulin-like growth factor systems.

    PubMed

    Edmondson, Stephanie R; Thumiger, Susan P; Werther, George A; Wraight, Christopher J

    2003-12-01

    GH and IGF-I and -II were first identified by their endocrine activity. Specifically, IGF-I was found to mediate the linear growth-promoting actions of GH. It is now evident that these two growth factor systems also exert widespread activity throughout the body and that their actions are not always interconnected. The literature highlights the importance of the GH and IGF systems in normal skin homeostasis, including dermal/epidermal cross-talk. GH activity, sometimes mediated via IGF-I, is primarily evident in the dermis, particularly affecting collagen synthesis. In contrast, IGF action is an important feature of the dermal and epidermal compartments, predominantly enhancing cell proliferation, survival, and migration. The locally expressed IGF binding proteins play significant and complex roles, primarily via modulation of IGF actions. Disturbances in GH and IGF signaling pathways are implicated in the pathophysiology of several skin perturbations, particularly those exhibiting epidermal hyperplasia (e.g., psoriasis, carcinomas). Additionally, many studies emphasize the potential use of both growth factors in the treatment of skin wounds; for example, burn patients. This overview concerns the role and mechanisms of action of the GH and IGF systems in skin and maintenance of epidermal integrity in both health and disease.

  15. Effects of hepatocyte growth factor on glutathione synthesis, growth, and apoptosis is cell density-dependent

    SciTech Connect

    Yang Heping; Magilnick, Nathaniel; Xia Meng; Lu, Shelly C.

    2008-01-15

    Hepatocyte growth factor (HGF) is a potent hepatocyte mitogen that exerts opposing effects depending on cell density. Glutathione (GSH) is the main non-protein thiol in mammalian cells that modulates growth and apoptosis. We previously showed that GSH level is inversely related to cell density of hepatocytes and is positively related to growth. Our current work examined whether HGF can modulate GSH synthesis in a cell density-dependent manner and how GSH in turn influence HGF's effects. We found HGF treatment of H4IIE cells increased cell GSH levels only under subconfluent density. The increase in cell GSH under low density was due to increased transcription of GSH synthetic enzymes. This correlated with increased protein levels and nuclear binding activities of c-Jun, c-Fos, p65, p50, Nrf1 and Nrf2 to the promoter region of these genes. HGF acts as a mitogen in H4IIE cells under low cell density and protects against tumor necrosis factor {alpha} (TNF{alpha})-induced apoptosis by limiting JNK activation. However, HGF is pro-apoptotic under high cell density and exacerbates TNF{alpha}-induced apoptosis by potentiating JNK activation. The increase in cell GSH under low cell density allows HGF to exert its full mitogenic effect but is not necessary for its anti-apoptotic effect.

  16. Growth hormone and insulin-like growth factor 1 affect the severity of Graves' disease.

    PubMed

    Di Cerbo, Alfredo; Pezzuto, Federica; Di Cerbo, Alessandro

    2017-01-01

    Graves' disease, the most common form of hyperthyroidism in iodine-replete countries, is associated with the presence of immunoglobulins G (IgGs) that are responsible for thyroid growth and hyperfunction. In this article, we report the unusual case of a patient with acromegaly and a severe form of Graves' disease. Here, we address the issue concerning the role of growth hormone (GH) and insulin-like growth factor 1 (IGF1) in influencing thyroid function. Severity of Graves' disease is exacerbated by coexistent acromegaly and both activity indexes and symptoms and signs of Graves' disease improve after the surgical remission of acromegaly. We also discuss by which signaling pathways GH and IGF1 may play an integrating role in regulating the function of the immune system in Graves' disease and synergize the stimulatory activity of Graves' IgGs. Clinical observations have demonstrated an increased prevalence of euthyroid and hyperthyroid goiters in patients with acromegaly.The coexistence of acromegaly and Graves' disease is a very unusual event, the prevalence being <1%.Previous in vitro studies have showed that IGF1 synergizes the TSH-induced thyroid cell growth-activating pathways independent of TSH/cAMP/PKA cascade.We report the first case of a severe form of Graves' disease associated with acromegaly and show that surgical remission of acromegaly leads to a better control of symptoms of Graves' disease.

  17. Nerve growth factor from cobra venom inhibits the growth of Ehrlich tumor in mice.

    PubMed

    Osipov, Alexey V; Terpinskaya, Tatiana I; Kryukova, Elena V; Ulaschik, Vladimir S; Paulovets, Lubov V; Petrova, Elena A; Blagun, Ekaterina V; Starkov, Vladislav G; Utkin, Yuri N

    2014-02-26

    The effects of nerve growth factor (NGF) from cobra venom (cvNGF) on growth of Ehrlich ascites carcinoma (EAC) cells inoculated subcutaneously in mice have been studied. The carcinoma growth slows down, but does not stop, during a course of cvNGF injections and restores after the course has been discontinued. The maximal anti-tumor effect has been observed at a dose of 8 nmoles cvNGF/kg body weight. cvNGF does not impact on lifespan of mice with grafted EAC cells. K252a, a tyrosine kinase inhibitor, attenuates the anti-tumor effect of cvNGF indicating the involvement of TrkA receptors in the process. cvNGF has induced also increase in body weight of the experimental animals. In overall, cvNGF shows the anti-tumor and weight-increasing effects which are opposite to those described for mammalian NGF (mNGF). However in experiments on breast cancer cell line MCF-7 cvNGF showed the same proliferative effects as mNGF and had no cytotoxic action on tumor cells in vitro. These data suggest that cvNGF slows down EAC growth via an indirect mechanism in which TrkA receptors are involved.

  18. Nerve Growth Factor from Cobra Venom Inhibits the Growth of Ehrlich Tumor in Mice

    PubMed Central

    Osipov, Alexey V.; Terpinskaya, Tatiana I.; Kryukova, Elena V.; Ulaschik, Vladimir S.; Paulovets, Lubov V.; Petrova, Elena A.; Blagun, Ekaterina V.; Starkov, Vladislav G.; Utkin, Yuri N.

    2014-01-01

    The effects of nerve growth factor (NGF) from cobra venom (cvNGF) on growth of Ehrlich ascites carcinoma (EAC) cells inoculated subcutaneously in mice have been studied. The carcinoma growth slows down, but does not stop, during a course of cvNGF injections and restores after the course has been discontinued. The maximal anti-tumor effect has been observed at a dose of 8 nmoles cvNGF/kg body weight. cvNGF does not impact on lifespan of mice with grafted EAC cells. K252a, a tyrosine kinase inhibitor, attenuates the anti-tumor effect of cvNGF indicating the involvement of TrkA receptors in the process. cvNGF has induced also increase in body weight of the experimental animals. In overall, cvNGF shows the anti-tumor and weight-increasing effects which are opposite to those described for mammalian NGF (mNGF). However in experiments on breast cancer cell line MCF-7 cvNGF showed the same proliferative effects as mNGF and had no cytotoxic action on tumor cells in vitro. These data suggest that cvNGF slows down EAC growth via an indirect mechanism in which TrkA receptors are involved. PMID:24577582

  19. Osteocalcin induces growth hormone/insulin-like growth factor-1 system by promoting testosterone synthesis in male mice.

    PubMed

    Li, Y; Li, K

    2014-10-01

    Osteocalcin has been shown to enhance testosterone production in men. In the present study, we investigated the effects of osteocalcin on testosterone and on induction of the growth hormone/insulin-like growth factor-1 axis. Osteocalcin injection stimulated growth, which could be inhibited by castration. In addition, osteocalcin induced testosterone secretion in testes both in vivo and in vitro. Using real-time polymerase chain reaction and Western blotting, we showed that growth hormone expression was significantly increased in the pituitary after osteocalcin injection (p<0.05). Growth hormone expression in CLU401 mouse pituitary cells was also significantly stimulated (p<0.05) by osteocalcin-induced MA-10 cells. Osteocalcin injection also promoted hepatic expression of growth hormone receptor and insulin-like growth factor-1 (p<0.05), as demonstrated by real-time polymerase chain reaction and Western blotting. Similarly, osteocalcin-induced MA-10 cells promoted growth hormone receptor and insulin-like growth factor-1 expression in NCTC1469 cells. These results suggest that the growth-stimulating activities of osteocalcin are mediated by testicular testosterone secretion, and thus provide valuable information regarding the regulatory effects of osteocalcin expression on the growth hormone/insulin-like growth factor-1 axis via reproductive activities.

  20. William H. Daughaday and the foundations of modern research into growth hormone and the insulin-like growth factors.

    PubMed

    Rotwein, Peter

    2013-01-01

    This vignette summarizes some of the scientific accomplishments of Dr. William H. Daughaday, a founder of modern research into the biological effects of growth hormone and the insulin-like growth factors, and formulator of the somatomedin hypothesis of GH actions on growth.

  1. 47 CFR 36.604 - Calculation of the rural growth factor.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Calculation of the rural growth factor. 36.604 Section 36.604 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES... § 36.604 Calculation of the rural growth factor. The Rural Growth Factor (RGF) is equal to the sum...

  2. 47 CFR 36.604 - Calculation of the rural growth factor.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Calculation of the rural growth factor. 36.604 Section 36.604 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES... § 36.604 Calculation of the rural growth factor. The Rural Growth Factor (RGF) is equal to the sum...

  3. [The concentration of growth factors in patients with inherent and acquired shortenings of limbs bones].

    PubMed

    Strogov, M V; Luneva, S N; Novikov, K I

    2013-04-01

    The article deals with the results of study of level of growth factors in blood serum of patients with inherent and post-traumatic shortenings of limbs' bones. The detection in blood serum the level of epidermal growth factor insulin-like growth factor I and angiopoetins is proposed to monitor in given patients the reparative bone formation.

  4. Growth hormone, insulin-like growth factor-1 and the aging brain.

    PubMed

    Ashpole, Nicole M; Sanders, Jessica E; Hodges, Erik L; Yan, Han; Sonntag, William E

    2015-08-01

    Growth hormone (GH) and insulin-like growth factor (IGF)-1 regulate the development and function of cells throughout the body. Several clinical diseases that result in a decline in physical and mental functions are marked by mutations that disrupt GH or IGF-1 signaling. During the lifespan there is a robust decrease in both GH and IGF-1. Because GH and IGF-1 are master regulators of cellular function, impaired GH and IGF-1 signaling in aging/disease states leads to significant alterations in tissue structure and function, especially within the brain. This review is intended to highlight the effects of the GH and IGF-1 on neuronal structure, function, and plasticity. Furthermore, we address several potential mechanisms through which the age-related reductions in GH and IGF-1 affect cognition. Together, the studies reviewed here highlight the importance of maintaining GH and IGF-1 signaling in order to sustain proper brain function throughout the lifespan.

  5. The Role of the Growth Hormone/Insulin-Like Growth Factor System in Visceral Adiposity

    PubMed Central

    Lewitt, Moira S

    2017-01-01

    There is substantial evidence that the growth hormone (GH)/insulin-like growth factor (IGF) system is involved in the pathophysiology of obesity. Both GH and IGF-I have direct effects on adipocyte proliferation and differentiation, and this system is involved in the cross-talk between adipose tissue, liver, and pituitary. Transgenic animal models have been of importance in identifying mechanisms underlying these interactions. It emerges that this system has key roles in visceral adiposity, and there is a rationale for targeting this system in the treatment of visceral obesity associated with GH deficiency, metabolic syndrome, and lipodystrophies. This evidence is reviewed, gaps in knowledge are highlighted, and recommendations are made for future research. PMID:28469442

  6. 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

  7. [Study on the expressions of basic fibroblast growth factor and nervous growth factor genes in rat cerebral concussion].

    PubMed

    Peng, Rui-yun; Gao, Ya-bing; Xiao, Xing-yi; Wang, De-wen; Chen, Hao-yu; Wu, Xiao-hong; Liu, Jie; Hu, Wen-hua; Cai, Bao-ren

    2003-04-01

    To study the expressions of basic fibroblast growth factor (bFGF) and nervous growth factor(NGF) genes in rat cerebral concussion. Eighty Wistar male rats were used for animal model of cerebral concussion, which were sacrificed on 1, 3, 7, 14 and 30 days after injury and the brain tissue was taken out. The expressions of bFGF and NGF genes were studied in the course of cerebral concussion by means of immunohistochemistry and in situ hybridization. Rats in 100 g group were seen the clinical manifestation for typical cerebral concussion. The protein and mRNA of bFGF were increased on day 1, obtained at peak on day 3-7, decreased on day 14 and also increased on day 30 compared with controls. The positive area was seen in the plasma of neurons in cerebral cortex, hippocampus, thalamus and cerebellum. NGF protein and mRNA showed strong positive and increased in the plasma of neurons in cerebral cortex, hippocampus, thalamus and cerebellum on day 1, and they were continuously positive but gradually decreased within 30 days after injury. The expression of bFGF gene participates in the course of cerebral concussion, might play an important role in the nervous cells degeneration and necrosis; NGF gene expression participates in the whole course of cerebral concussion, especially in the early phase.

  8. Heparin-Binding Epidermal Growth Factor-Like Growth Factor Enhances Aquaporin 3 Expression and Function During Mouse Embryo Implantation.

    PubMed

    Fang, Chuan-Xiang; Nong, Ying-Qi; Liu, Feng-Hua; Fan, Lin; Chen, Ye

    2017-03-01

    Aquaporin 3 (AQP3) is highly expressed in peri-implantation blastocyst trophoblastic cells, indicating its role in cytotrophoblast invasion during embryo implantation. However, the mechanism underlying the regulation of AQP3 expression during embryo implantation remains unclear. In this study, an in vitro co-culture system of blastocysts on a monolayer of uterine endometrial cells was used to mimic in vivo process of embryo attachment and invasion to uterine endometrium and treated with different concentrations of heparin-binding epidermal growth factor-like growth factor (HB-EGF). The results showed that HB-EGF enhanced AQP3 expression in blastocysts in a dose-dependent manner and promoted the attachment and outgrowth of blastocysts on the monolayer of uterine endometrial cells. When the AQP3 activity was inhibited by copper sulfate, both the attachment and outgrowth of blastocysts were inhibited. Furthermore, HB-EGF induced the phosphorylation of EGF receptor (EGFR) and extracellular signal-regulated kinase (ERK). PD153035 (EGFR inhibitor) and U0126 (ERK inhibitor) inhibited AQP3 expression and also the attachment and outgrowth of blastocysts. Collectively, our findings provide the first evidence that HB-EGF stimulates EGFR/ERK signaling to promote AQP3 expression in trophoblastic cells, and AQP3 plays a vital role in HB-EGF-induced embryo implantation.

  9. Heparin Binding–Epidermal Growth Factor-Like Growth Factor for the Regeneration of Chronic Tympanic Membrane Perforations in Mice

    PubMed Central

    Kim, Sungwoo; Varsak, Yasin Kursad; Yang, Yunzhi Peter

    2015-01-01

    We aim to explore the role of epidermal growth factor (EGF) ligand shedding in tympanic membrane wound healing and to investigate the translation of its modulation in tissue engineering of chronic tympanic membrane perforations. Chronic suppurative otitis media (CSOM) is an infected chronic tympanic membrane perforation. Up to 200 million suffer from its associated hearing loss and it is the most common cause of pediatric hearing loss in developing countries. There is a need for nonsurgical treatment due to a worldwide lack of resources. In this study, we show that EGF ligand shedding is essential for tympanic membrane healing as it's inhibition, with KB-R7785, leads to chronic perforation in 87.9% (n=58) compared with 0% (n=20) of controls. We then show that heparin binding–EGF-like growth factor (5 μg/mL), which acts to shed EGF ligands, can regenerate chronic perforations in mouse models with 92% (22 of 24) compared with 38% (10 of 26), also with eustachian tube occlusion with 94% (18 of 19) compared with 9% (2 of 23) and with CSOM 100% (16 of 16) compared with 41% (7 of 17). We also show the nonototoxicity of this treatment and its hydrogel delivery vehicle. This provides preliminary data for a clinical trial where it could be delivered by nonspecialist trained healthcare workers and fulfill the clinical need for a nonsurgical treatment for chronic tympanic membrane perforation and CSOM. PMID:25567607

  10. Platelet-derived growth factor mimics phorbol diester action on epidermal growth factor receptor phosphorylation at threonine-654

    SciTech Connect

    Davis, R.J.; Czech, M.P.

    1985-06-01

    Addition of platelet-derived growth factor (PDGF) to quiescent WI-38 human fetal lung fibroblasts mimics the effect of tumor-promoting phorbol diesters to inhibit the high-affinity binding of SVI-labeled epidermal growth factor ( SVI-EGF). PDGF, like phorbol diesters, was found to increase the phosphorylation state of EGF receptors immunoprecipitated from intact fibroblasts that were labeled to equilibrium with (TSP)phosphate. Phosphoamino acid analysis of the EGF receptors indicated that both PDGF and phorbol diesters increased the level of (TSP)phosphoserine and (TSP)phosphothreonine. Phosphopeptide mapping of the EGF receptor demonstrated that PDGF increased the phosphorylation of several sites and induced the phosphorylation of a site that was not observed to be phosphorylated on EGF receptors isolated from control cells. This latter phosphorylation site on the EGF receptor was identified as threonine-654. These results are consistent with the hypothesis that increases in diacylglycerol and CaS levels caused by addition of PDGF to fibroblasts activate protein kinase C and that this kinase, at least in part, mediates the effect of PDGF on the phosphorylation of the EGF receptor. The data further suggest that protein kinase C may play an important role in the regulation of cellular metabolism and proliferation by PDGF.

  11. Biochemical characterization of the molecular interaction between recombinant basic fibroblast growth factor and a recombinant soluble fibroblast growth factor receptor.

    PubMed Central

    Caccia, P; Cletini, O; Isacchi, A; Bergonzoni, L; Orsini, G

    1993-01-01

    The extracellular domain of human fibroblast growth factor receptor (XC-FGF-R) was expressed in Escherichia coli. The protein was purified to homogeneity and the interaction with basic fibroblast growth factor (bFGF), its physiological ligand, was examined. Using resins on which bFGF was reversibly bound, we analysed the characteristics of the binding between XC-FGF-R and immobilized bFGF. We also investigated the stoichiometry of the binding between XC-FGF-R and recombinant human bFGF (rhbFGF) applying non-denaturing gel electrophoresis, chemical cross-linking followed by SDS/PAGE, and gel-filtration chromatography. In cross-linking and gel-filtration chromatography experiments, a 1:1 complex between rhbFGF and XC-FGF-R was observed. The complex was separated from the non-complexed proteins using non-denaturing PAGE in the presence of 0.1% Triton X-100. The band corresponding to the complex was recognized by specific antibodies directed against bFGF and its receptor, blotted on poly(vinylidene difluoride) membranes and submitted to sequence and amino acid analysis. The data obtained from these determinations confirmed the formation of a 1:1 complex between rhbFGF and XC-FGF-R. Images Figure 1 Figure 2 Figure 3 Figure 5 PMID:8379918

  12. Expression of Vascular Endothelial Growth Factor and Epidermal Growth Factor Receptor in Pancreatic Ductal Adenocarcinomas, Neuroendocrine Tumours and Chronic Pancreatitis

    PubMed Central

    Angelescu, Radu; Burada, Florin; Angelescu, Cristina; Gheonea, Dan Ionut; Iordache, Sevastița; Mixich, Francisc; Ioana, Mihai; Săftoiu, Adrian

    2013-01-01

    Objective: Angiogenesis is a crucial event for pancreatic carcinogenesis, and it also plays an important role in chronic pancreatitis. The aim of our study was to evaluate the mRNA expression of vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) in chronic inflammatory or malignant pancreatic pathology in order to elucidate the differences in expression patterns and potential clinical implications. Methods: Thirty-five patients who had undergone endoscopic ultrasonography followed by endoscipic ultrasound-guided fine needle aspiration (EUS-FNA) of focal pancreatic masses were included in the study. VEGF and EGFR mRNA expression levels in the samples collected by EUS-FNA were analyzed using quantitative real-time polymerase chain reaction (PCR). Results: VEGF expression was detected in all chronic pancreatitis and adenocarcinoma samples and in only 62.5% of pancreatic neuroendocrine tumors. EGFR expression was detected in only 40% of the chronic pancreatitis cases, 76.9% of adenocarcinomas and in 50% of pancreatic neuroendocrine tumors. Both VEGF and EGFR mRNA levels were significantly higher in pancreatic ductal adenocarcinoma than those in normal tissue. VEGF expression inversely correlated with pancreatic ductal adenocarcinoma size, while EGFR expression was related to local invasiveness of adenocarcinoma. Conclusion: Both VEGF and EGFR mRNA expression in EUS-FNA samples may be used as a diagnostic marker associated with invasiveness in patients with pancreatic adenocarcinoma. PMID:24949370

  13. Mammary tumorigenesis induced by fibroblast growth factor receptor 1 requires activation of the epidermal growth factor receptor.

    PubMed

    Bade, Lindsey K; Goldberg, Jodi E; Dehut, Hazel A; Hall, Majken K; Schwertfeger, Kathryn L

    2011-09-15

    Fibroblast growth factor receptor 1 (FGFR1) is an oncoprotein with known involvement in mammary tumorigenesis. To understand how FGFR1 signaling promotes mammary tumorigenesis, an inducible FGFR1 (iFGFR1) system was created previously. Previous studies have demonstrated that upon iFGFR1 activation in vivo, the epidermal growth factor (EGF) ligands amphiregulin (AREG) and epiregulin (EREG) are upregulated. Both AREG and EREG interact with the EGF receptor (EGFR). Here, we investigated whether the FGFR1-induced increase in AREG and EREG expression might coordinately increase EGFR signaling to promote mammary tumorigenesis. Treatment of mouse mammary epithelial cells with either AREG or EREG conferred a greater migratory potential, increased cellular proliferation and increased extracellular regulated kinase 1/2 (ERK1/2) activation. These effects could be blocked with the EGFR-specific inhibitor erlotinib, suggesting that they are EGFR-dependent. In transgenic mice with iFGFR1 under the control of the mouse mammary tumor virus (MMTV) promoter, iFGFR1 activation also led to increased mammary epithelial cell proliferation that was inhibited with erlotinib. Taken together, these data suggest that AREG and EREG mediate tumorigenic phenotypes by activating EGFR signaling, and that the oncogenic potential of FGFR1 requires EGFR activation to promote mammary tumorigenesis.

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

    PubMed Central

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

    2015-01-01

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

  15. Modeling the epidermal growth factor -- epidermal growth factor receptor l2 domain interaction: implications for the ligand binding process.

    PubMed

    Jorissen, Robert N; Treutlein, Herbert R; Epa, V Chandana; Burgess, Antony W

    2002-06-01

    Signaling from the epidermal growth factor (EGF) receptor is triggered by the binding of ligands such as EGF or transforming growth factor alpha (TGF-alpha) and subsequent receptor dimerization. An understanding of these processes has been hindered by the lack of structural information about the ligand-bound, dimerized EGF receptor. Using an NMR-derived structure of EGF and a homology model of the major ligand binding domain of the EGF receptor and experimental data, we modeled the binding of EGF to this EGF receptor fragment. In this low resolution model of the complex, EGF sits across the second face of the EGF receptor L2 domain and EGF residues 10-16, 36-37, 40-47 bind to this face. The structural model is largely consistent with previously published NMR data describing the residues of TGF-alpha which interact strongly with the EGF receptor. Other EGF residues implicated in receptor binding are accounted by our proposal that the ligand binding is a two-step process with the EGF binding to at least one other site of the receptor. This three-dimensional model is expected to be useful in the design of ligand-based antagonists of the receptor.

  16. Plasma vascular endothelial growth factor A and placental growth factor: novel biomarkers of pulmonary hypertension in congenital diaphragmatic hernia.

    PubMed

    Patel, Neil; Moenkemeyer, Florian; Germano, Susie; Cheung, Michael M H

    2015-02-15

    Pulmonary hypertension (PH) due to abnormal pulmonary vascular development is an important determinant of illness severity in congenital diaphragmatic hernia (CDH). Vascular endothelial growth factor A (VEGFA) and placental growth factor (PLGF) may be important mediators of pulmonary vascular development in health and disease. This prospective study investigated the relationship between plasma VEGFA and PLGF and measures of pulmonary artery pressure, oxygenation, and cardiac function in CDH. A cohort of 10 infants with CDH consecutively admitted to a surgical neonatal intensive care unit (NICU) was recruited. Eighty serial plasma samples were obtained and analyzed by multiplex immunoassay to quantify VEGFA and PLGF. Concurrent assessment of pulmonary artery pressure (PAP) and cardiac function were made by echocardiography. Plasma VEGFA was higher and PLGF was lower in CDH compared with existing normative data. Combined plasma VEGFA:PLGF ratio correlated positively with measures of PAP, diastolic ventricular dysfunction, and oxygenation index. Nonsurvivors had higher VEGFA:PLGF ratio than survivors at days 3-4 of life and in the second week of life. These findings suggest that increased plasma VEGFA and reduced PLGF correlate with clinical severity of pulmonary vascular disease and may be associated with adverse outcome in CDH. This potential role for combined plasma VEGFA and PLGF in CDH as disease biomarkers, pathogenic mediators, and therapeutic targets merits further investigation.

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

    PubMed Central

    Wimmel, A; Wiedenmann, B; Rosewicz, S

    2003-01-01

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

  18. Epidermal growth factor receptor (EGFR) involvement in successful growth hormone (GH) signaling in GH transduction defect.

    PubMed

    Kostopoulou, Eirini; Rojas-Gil, Andrea Paola; Karvela, Alexia; Spiliotis, Bessie E

    2017-02-01

    Growth hormone (GH) transduction defect (GHTD) is a growth disorder with impaired signal transducer and activator of transcription 3 (STAT3) phosphorylation mediated by overexpression of cytokine-inducible SH2-containing protein (CIS), which causes increased growth hormone receptor (GHR) degradation. This study investigated the role of epidermal growth factor (EGF) in the restoration of normal GH signaling in GHTD. Protein expression, cellular localization and physical contact of proteins of the GH and EGF signaling pathways were studied by Western immunoblotting, immunofluorescence and co-immunoprecipitation, respectively. These were performed in fibroblasts of one GHTD patient (P) and one control child (C) at the basal state and after induction with human GH (hGH) 200 μg/L (GH200), either with or without silencing of CIS mRNA, and after induction with hGH 1000 μg/L (GH1000) or 50 ng/mL EGF. The membrane availability of the EGF receptor (EGFR) and the activated EGFR (pEGFR) was increased in P only after simultaneous GH200 and silencing of CIS mRNA or with GH1000, whereas this occurred in C after GH200 alone. After EGF induction, the membrane localization of GHR, STAT3 and that of EGFR were increased in P more than in C. In conclusion, in GHTD, the EGFR seems to participate in successful GH signaling, but induction of GHTD fibroblasts with a higher dose of hGH is needed. The EGF/EGFR pathway, in contrast to the GH/GHR pathway, seems to function normally in P and is more primed compared to C. The involvement of the EGFR in successful GH signaling may explain the catch-up growth seen in the Ps when exogenous hGH is administered.

  19. Transforming growth factor-beta inhibition of proteasomal activity: a potential mechanism of growth arrest.

    PubMed

    Tadlock, Laura; Yamagiwa, Yoko; Hawker, James; Marienfeld, Carla; Patel, Tushar

    2003-08-01

    Although the proteasome plays a critical role in the controlled degradation of proteins involved in cell cycle control, the direct modulation of proteasomal function by growth regulatory signaling has not yet been demonstrated. We assessed the effect of transforming growth factor (TGF)-beta, a potent inhibitor of cell growth, on proteasomal function. TGF-beta selectively decreased hydrolysis of the proteasomal substrate Cbz-Leu-Leu-Leu-7-amido-4-methyl-coumarin (z-LLL-AMC) in a concentration-dependent manner but did not inhibit hydrolysis of other substrates Suc-Leu-Leu-Val-Tyr-AMC (suc-LLVY-AMC) or Cbz-Leu-Leu-Glu-AMC (z-LLE-AMC). An increase in intracellular oxidative injury occurred during incubation with TGF-beta. Furthermore, in vitro hydrolysis of z-LLL-AMC, but not suc-LLVY-AMC, was decreased by hydrogen peroxide. TGF-beta did not increase cellular expression of heat shock protein (HSP)90, a potent inhibitor of z-LLL-AMC hydrolysis in vitro. The physiological relevance of TGF-beta inhibition of proteasomal activity was studied by assessing the role of z-LLL-AMC hydrolysis on cyclin-dependent kinase inhibitor expression and cell growth. TGF-beta increased expression of p27KIP1 but did not alter expression of p21WAF1 or p16INK4A. The peptide aldehyde Cbz-Leu-Leu-leucinal (LLL-CHO or MG132) potently inhibited z-LLL-AMC hydrolysis in cell extracts as well as increasing p27KIP1 and decreasing cell proliferation. Thus growth inhibition by TGF-beta decreases a specific proteasomal activity via an HSP90-independent mechanism that may involve oxidative inactivation or modulation of proteasomal subunit composition and results in altered cellular expression of key cell cycle regulatory proteins such as p27KIP1.

  20. P2X7R suppression promotes glioma growth through epidermal growth factor receptor signal pathway.

    PubMed

    Fang, Jingqin; Chen, Xiao; Zhang, Letian; Chen, Jinhua; Liang, Yi; Li, Xue; Xiang, Jianbo; Wang, Lili; Guo, Guangkuo; Zhang, Bo; Zhang, Weiguo

    2013-06-01

    P2X7 receptor (P2X7R) has been shown to mediate an anticancer effect via apoptosis in different types of cancer. However, whether P2X7R exerts a promoting or suppressive effect on brain glioma is still a controversial issue and its underlying mechanism remains unknown. We showed here that P2X7R suppression exerted a pro-growth effect on glioma through directly promoting cells proliferation and pro-angiogenesis, which was associated with epidermal growth factor receptor (EGFR) signaling. The P2X7R was markedly downregulated by cells exposure to the P2X7R antagonist, brilliant blue G (BBG), moreover, the cells proliferation was enhanced in a dose-dependent manner and the expression of EGFR or p-EGFR protein was significantly upregulated. By constructing C6 cells with reduced expression of P2X7R using shRNA, we also demonstrated strong upregulation in cells proliferation and EGFR/p-EGFR expression. However, this effect of BBG was reversed in the presence of gefitinib or suramin. Magnetic resonance imaging and computed tomography perfusion showed that the BBG or P2X7R shRNA promoted the tumor growth by about 40% and 50%, respectively, and significantly increased angiogenesis. Nissl and Ki-67 staining also confirmed that BBG or P2X7R shRNA notably increased the tumor growth. More importantly, either BBG or P2X7R shRNA could markedly upregulated the expression of EGFR, p-EGFR, HIF-1α and VEGF in glioma cells. In conclusion, P2X7R suppression exerts a promoting effect on glioma growth, which is likely to be related to upregulated EGFR, HIF-1α and VEGF expression. These findings provide important clues to the molecular basis of anticancer effect of targeting purinergic receptors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Targeting fibroblast growth factor receptor signaling in hepatocellular carcinoma.

    PubMed

    Cheng, Ann-Lii; Shen, Ying-Chun; Zhu, Andrew X

    2011-01-01

    Hepatocellular carcinoma (HCC) is the primary type of liver cancer, and both the age-adjusted incidence and mortality of HCC have steadily increased in recent years. Advanced HCC is associated with a very poor survival rate. Despite accumulating data regarding the risk factors for HCC, the mechanisms that contribute to HCC tumorigenesis remain poorly understood. Signaling through the fibroblast growth factor (FGF) family is involved in fibrosis and its progression to cirrhosis of the liver, which is a risk factor for the development of HCC. Furthermore, several alterations in FGF/FGF receptor (FGFR) signaling correlate with the outcomes of HCC patients, suggesting that signaling through this family of proteins contributes to the development or progression of HCC tumors. Currently, there are no established systemic treatments for patients with advanced HCC in whom sorafenib treatment has failed or who were unable to tolerate it. Recently, several multikinase inhibitors that target FGFRs have demonstrated some early evidence of antitumor activity in phase I/II trials. Therefore, this review discusses the molecular implications of FGFR-mediated signaling in HCC and summarizes the clinical evidence for novel FGFR-targeted therapies for HCC currently being studied in clinical trials.

  2. Muscle growth in young horses: Effects of age, cytokines, and growth factors.

    PubMed

    LaVigne, E K; Jones, A K; Londoño, A Sanchez; Schauer, A S; Patterson, D F; Nadeau, J A; Reed, S A

    2015-12-01

    Success as equine athletes requires proper muscle growth in young horses. Muscle hypertrophy occurs through protein synthesis and the contribution of muscle satellite cells, which can be stimulated or inhibited by cytokines and growth factors present during exercise and growth. The hypotheses of this study were that 1) the LM area in young horses would increase over 1 yr, and 2) specific cytokines and growth factors (IL-1β, IL-6, tumor necrosis factor [TNF]-α, IGF-I, and fibroblast growth factor [FGF]-2) would alter proliferation and differentiation of satellite cells isolated from young horses. Fourteen horses were divided into 3 age groups: weanlings ( = 5), yearlings to 2 yr olds ( = 4), and 3 to 4 yr olds ( = 5). The area, height, and subcutaneous fat depth of the LM were measured using ultrasonography, and BW and BCS were taken in October (Fall1), April (Spring), and October of the following year (Fall2). Satellite cells obtained from 10-d-old foals ( = 4) were cultured in the presence of IL-6, IL-1β, TNF-α, IGF-I, or FGF-2 before evaluation of proliferation and differentiation. Data were analyzed using PROC MIXED in SAS. Body weight increased from Fall1 to Spring in weanlings ( < 0.001) and increased in all horses from Spring to Fall2 ( ≤ 0.02). Area and height of the LM increased over time ( < 0.001) and with increasing age group of horse ( ≤ 0.03), although there was no interaction of time and age ( > 0.61). There was a significant increase in LM area in all animals from Spring to Fall2 ( < 0.001) but not from Fall1 to Spring. Interleukin-6 and TNF-α decreased satellite cell proliferation by 14.9 and 11.5%, respectively ( ≤ 0.01). Interleukin-6 increased fusion 6.2%, whereas TNF-α decreased fusion 8.7% compared with control cells ( ≤ 0.001). Interleukin-1β had no effect on proliferation ( = 0.32) but tended to decrease fusion ( = 0.06). Satellite cell proliferation was increased 28.8 and 73.0% by IGF-I and FGF-2, respectively ( < 0

  3. Arteriogenic therapy by intramyocardial sustained delivery of a novel growth factor combination prevents chronic heart failure.

    PubMed

    Banquet, Sébastien; Gomez, Elodie; Nicol, Lionel; Edwards-Lévy, Florence; Henry, Jean-Paul; Cao, Renhai; Schapman, Damien; Dautreaux, Brigitte; Lallemand, Francoise; Bauer, Fabrice; Cao, Yihai; Thuillez, Christian; Mulder, Paul; Richard, Vincent; Brakenhielm, Ebba

    2011-08-30

    Therapeutic angiogenesis is a promising approach for the treatment of cardiovascular diseases, including myocardial infarction and chronic heart failure. We aimed to improve proangiogenic therapies by identifying novel arteriogenic growth factor combinations, developing injectable delivery systems for spatiotemporally controlled growth factor release, and evaluating functional consequences of targeted intramyocardial growth factor delivery in chronic heart failure. First, we observed that fibroblast growth factor and hepatocyte growth factor synergistically stimulate vascular cell migration and proliferation in vitro. Using 2 in vivo angiogenesis assays (n=5 mice per group), we found that the growth factor combination results in a more potent and durable angiogenic response than either growth factor used alone. Furthermore, we determined that the molecular mechanisms involve potentiation of Akt and mitogen-activated protein kinase signal transduction pathways, as well as upregulation of angiogenic growth factor receptors. Next, we developed crosslinked albumin-alginate microcapsules that sequentially release fibroblast growth factor-2 and hepatocyte growth factor. Finally, in a rat model of chronic heart failure induced by coronary ligation (n=14 to 15 rats per group), we found that intramyocardial slow release of fibroblast growth factor-2 with hepatocyte growth factor potently stimulates angiogenesis and arteriogenesis and prevents cardiac hypertrophy and fibrosis, as determined by immunohistochemistry, leading to improved cardiac perfusion after 3 months, as shown by magnetic resonance imaging. These multiple beneficial effects resulted in reduced adverse cardiac remodeling and improved left ventricular function, as revealed by echocardiography. Our data showing the selective advantage of using fibroblast growth factor-2 together with hepatocyte growth factor suggest that this growth factor combination may constitute an efficient novel treatment for chronic

  4. Factors Affecting Growth of Pinus radiata in Chile

    NASA Astrophysics Data System (ADS)

    Alvarez-Munoz, Jose Santos

    The Chilean forestry industry is based on hundreds of thousands of hectares of Pinus radiata plantations that have been established in a variety of soil and climate conditions. This approach has resulted in highly variable plantation productivity even when the best available technology was used. Little information is known about the ecophysiology basis for this variability. We explored the spatial and temporal variation of stand growth in Chile using a network of permanent sample plots from Modelo Nacional de Simulacion de Pino radiata. We hypothesized that the climate would play an important role in the annual variations in productivity. To answer these questions we developed the following projects: (1) Determination of site resource availability from historical data from automatic weather stations (rainfall, temperatures) and a geophysical model for solar irradiation, (2) Determination of peak annual leaf area index (LAI) for selected permanent sample plots using remote sensing technologies, (3) Analysis of soil, climate, canopy and stand factors affecting the Pinus radiata plantation growth and the use efficiency of site resources. For project 1, we estimated solar irradiation using the r.sun , Hargreaves-Samani (HS), and Bristow-Campbell (BC) models and validated model estimates with observations from weather stations. Estimations from a calibrated r.sun model accounted for 94% of the variance (r2=0.94) in monthly mean measured values. The r.sun model performed quite well for a wide range of Chilean conditions when compared with the HS and BC models. Our estimates of global irradiation may be improved with better estimates of cloudiness as they become available. Our model was able to provide spatial estimates of daily, weekly, monthly and yearly solar irradiation. For project 2, we estimated the inter-annual variation of LAI (Leaf Area Index), using remote sensing technologies. We determined LAI using Landsat Thematic Mapper (TM) data covering a 5 year period

  5. Early exposure to ethanol or red wine and long-lasting effects in aged mice. A study on nerve growth factor, brain-derived neurotrophic factor, hepatocyte growth factor, and vascular endothelial growth factor.

    PubMed

    Ceccanti, Mauro; Mancinelli, Rosanna; Tirassa, Paola; Laviola, Giovanni; Rossi, Simona; Romeo, Marina; Fiore, Marco

    2012-02-01

    Prenatal ethanol exposure produces severe changes in brain, liver, and kidney through mechanisms involving growth factors. These molecules regulate survival, differentiation, maintenance, and connectivity of brain, liver, and kidney cells. Despite the abundant available data on the short and mid-lasting effects of ethanol intoxication, only few data show the long-lasting damage induced by early ethanol administration. The aim of this study was to investigate changes in nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), hepatocyte growth factor (HGF), and vascular endothelial growth factor (VEGF) in brain areas, liver, and kidney of 18-mo-old male mice exposed perinatally to ethanol at 11% vol or to red wine at the same ethanol concentration. The authors found that ethanol per se elevated NGF, BDNF, HGF, and VEGF measured by ELISA in brain limbic system areas. In the liver, early exposure to ethanol solution and red wine depleted BDNF and VEGF concentrations. In the kidney, red wine exposure only decreased VEGF. In conclusion, the present study shows that, in aged mice, early administration of ethanol solution induced long-lasting damage at growth factor levels in frontal cortex, hippocampus, and liver but not in kidney. Otherwise, in mice exposed to red wine, significant changes were observed in the liver and kidney but not in the hippocampus and frontal cortex. The brain differences in ethanol-induced toxicity when ethanol is administered alone or in red wine may be related to compounds with antioxidant properties present in the red wine. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  6. Expression of growth factors in canine flexor tendon after laceration in vivo.

    PubMed

    Tsubone, Tetsu; Moran, Steven L; Amadio, Peter C; Zhao, Chunfeng; An, Kai-Nan

    2004-10-01

    Growth factors, transforming growth factor beta (TGF-beta), epidermal growth factor (EGF), platelet-derived growth factor (PDGF), insulin-like growth factor (IGF), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF), are critical components of the cutaneous wound healing process. Little is known, however, about the expression of these growth factors in normal flexor tendon healing. In this study, we wished to examine which of these growth factors are present at 10 days following tendon injury in a canine flexor tendon repair model. Using immunohistochemical analysis, we found positive staining for all growth factors in both timing groups. TGF-beta was detected around the repair site and proximal to it. PDGF-AA, PDGF-BB and VEGF appeared in the whole tendon section following repair. EGF, IGF and bFGF were not seen in tenocytes but were present in inflammatory cells surrounding the repair site. These findings provide evidence that TGF-beta, EGF, PDGF-AA, PDGF-BB, IGF, bFGF and VEGF are all expressed at 10 days after tendon injury but by different cell types and in different locations. The time course of growth factor expression is an important element in wound healing, and a better understanding of where and when such factors are expressed may help in the development of methods to manipulate this expression, accelerate healing, and reduce adhesions.

  7. The Use of Growth Factors and Other Humoral Agents to Accelerate and Enhance Burn Wound Healing

    PubMed Central

    Ching, Yiu-Hei; Sutton, Thomas L.; Pierpont, Yvonne N.; Robson, Martin C.; Payne, Wyatt G.

    2011-01-01

    Objective: Certain cytokines, especially those known as growth factors, have been demonstrated to mediate or modulate burn wound healing. Experimental and clinical evidence suggests that there are therapeutic advantages to the wound healing process when these agents are utilized. Positive effects have been reported for 4 types of wounds seen in the burn patient: partial-thickness wounds, full-thickness wounds, interstices of meshed skin grafts, and skin graft donor sites. Methods: A comprehensive literature search was performed using the MEDLINE, Ovid, and Web of Science databases to identify pertinent articles regarding growth factors and other cytokines in burns and wound healing. Results: The current knowledge about cytokine growth factors and their potential therapeutic applications in burn wound healing are discussed and reviewed. Conclusions: Platelet-derived growth factor, fibroblast growth factors, epidermal growth factors, transforming growth factor alpha, vascular endothelial growth factor, insulin-like growth factor I, nerve growth factor, transforming growth factor beta, granulocyte-macrophage colony-stimulating factor, and amnion-derived cellular cytokine solution have all been suggested to enhance the rate and quality of healing in 1 or more of these wounds encountered in burn care. PMID:22084646

  8. A secreted peptide growth factor, phytosulfokine, acting as a stimulatory factor of carrot somatic embryo formation.

    PubMed

    Hanai, H; Matsuno, T; Yamamoto, M; Matsubayashi, Y; Kobayashi, T; Kamada, H; Sakagami, Y

    2000-01-01

    Somatic embryogenesis of the carrot (Daucus carota L.) depends on a set of factors, some of which accumulate in culture medium (conditioned medium, CM). When embryogenic cell clusters were transferred to an embryo-inducing medium, addition of CM derived from somatic embryo culture markedly stimulated somatic embryo formation. The active principles were purified using a simple bioassay system and identified to be phytosulfokines (PSKs), sulfated oligopeptide growth factors originally isolated from a CM derived from asparagus (Asparagus officinalis L.) mesophyll culture. Quantification studies using a competition ELISA system employing an anti-PSK-alpha polyclonal antibody showed that PSK production might be related to growth of cells, rather than development of somatic embryos. Thus the stimulatory effect of PSK on somatic embryo formation might be due to promotion of cell proliferation.

  9. The Insulin-like Growth Factor System: Towards Clinical Applications

    PubMed Central

    Bach, Leon A

    2004-01-01

    Insulin-like growth factors (IGF-I and II) are important endocrine, paracrine and autocrine mediators of physiological growth. They promote cellular proliferation, survival and differentiation. Their effects are mediated mainly through the IGF-I receptor, but IGFs also bind to the IGF-II/mannose 6-phosphate and insulin receptors. IGF activity is modulated by a family of six high-affinity IGF binding proteins (IGFBPs); in most situations, IGFBPs inhibit IGF actions but they may also enhance them. Assays are now available for IGF-I, IGF-II and individual IGFBPs. IGF-I and IGFBP-3 assays have some utility in the diagnosis and management of acromegaly and growth hormone deficiency. There is a large body of in vitro and in vivo evidence supporting a pathogenic role for alterations in the IGF system in many diseases, including diabetes, cancer, cardiovascular disease and neuromuscular disease. More recently, epidemiological studies have linked high IGF-I levels with some cancers and low IGF-I levels with ischaemic heart disease. Preliminary studies of recombinant IGF-I as a treatment for diabetes, osteoporosis and neuromuscular disease have been performed in humans. In contrast, there is considerable interest in developing IGF inhibitors for the treatment of cancer. This apparent paradox highlights the need to develop therapeutics beyond the natural ligands and inhibitors, with characteristics such as ligand and tissue specificity. This will only become possible as we increase our understanding of this complex system. Additionally, as IGF and IGFBP assays are becoming more readily available, their role in the diagnosis and monitoring of diseases should be more clearly defined in the near future. PMID:18458708

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

    PubMed Central

    Sulaiman, Wale; Nguyen, Doan H.

    2016-01-01

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

  11. Basic Fibroblast Growth Factor Induces Angiogenesis in vitro

    NASA Astrophysics Data System (ADS)

    Montesano, R.; Vassalli, J.-D.; Baird, A.; Guillemin, R.; Orci, L.

    1986-10-01

    Fibroblast growth factors (FGFs) are potent mitogens for vascular and capillary endothelial cells in vitro and can stimulate the formation of blood capillaries (angiogenesis) in vivo. A crucial event in this process is the invasion of the perivascular extracellular matrix by sprouting endothelial cells. Using a recently developed in vitro model of angiogenesis, we show here that highly purified basic pituitary FGF can induce capillary endothelial cells to invade a three-dimensional collagen matrix and to organize themselves to form characteristic tubules that resemble blood capillaries. We also show that basic FGF concomitantly stimulates endothelial cells to produce a urokinase-type plasminogen activator, a protease that has been implicated in the neovascular response. The results demonstrate that basic FGF can stimulate processes that are characteristic of angiogenesis in vivo, including endothelial cell migration, invasion, and production of plasminogen activator.

  12. Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor–Resistant Disease

    PubMed Central

    Ohashi, Kadoaki; Maruvka, Yosef E.; Michor, Franziska; Pao, William

    2013-01-01

    Purpose EGFR-mutant lung cancer was first described as a new clinical entity in 2004. Here, we present an update on new controversies and conclusions regarding the disease. Methods This article reviews the clinical implications of EGFR mutations in lung cancer with a focus on epidermal growth factor receptor tyrosine kinase inhibitor resistance. Results The discovery of EGFR mutations has altered the ways in which we consider and treat non–small-cell lung cancer (NSCLC). Patients whose metastatic tumors harbor EGFR mutations are expected to live longer than 2 years, more than double the previous survival rates for lung cancer. Conclusion The information presented in this review can guide practitioners and help them inform their patients about EGFR mutations and their impact on the treatment of NSCLC. Efforts should now concentrate on making EGFR-mutant lung cancer a chronic rather than fatal disease. PMID:23401451

  13. Insulin-like growth factor binding proteins 4-6.

    PubMed

    Bach, Leon A

    2015-10-01

    Insulin-like growth factor binding proteins (IGFBPs) 4-6 have important roles as modulators of IGF actions. IGFBP-4 and IGFBP-6 predominantly inhibit IGF actions, whereas IGFBP-5 may enhance these actions under some circumstances. IGFBP-6 is unique among the IGFBPs for its marked IGF-II binding preference. IGFBPs 4-6 are found in the circulation as binary complexes with IGFs that can enter tissues. Additionally, about half of the circulating IGFBP-5 is found in ternary complexes with IGFs and an acid labile subunit; this high molecular complex cannot leave the circulation and acts as an IGF reservoir. IGFBPs 4-6 also have IGF-independent actions. These IGFBPs are regulated in a cell-specific manner and their dysregulation may play a role in a range of diseases including cancer. However, there is no clear clinical indication for measuring serum levels of these IGFBPs at present.

  14. Inhibiting the Epidermal Growth Factor Receptor | Center for Cancer Research

    Cancer.gov

    The Epidermal Growth Factor Receptor (EGFR) is a widely distributed cell surface receptor that responds to several extracellular signaling molecules through an intracellular tyrosine kinase, which phosphorylates target enzymes to trigger a downstream molecular cascade. Since the discovery that EGFR mutations and amplifications are critical in a number of cancers, efforts have been under way to develop and use targeted EGFR inhibitors. These efforts have met with some spectacular successes, but many patients have not responded as expected, have subsequently developed drug-resistant tumors, or have suffered serious side effects from the therapies to date. CCR Investigators are studying EGFR from multiple vantage points with the goal of developing even better strategies to defeat EGFR-related cancers.

  15. Topical administration of adrenergic receptor pharmaceutics and nerve growth factor

    PubMed Central

    Steinle, Jena J

    2010-01-01

    Topical application of nerve growth factor (NGF) and adrenergic receptor pharmaceutics are currently in use for corneal ulcers and glaucoma. A recent interest in the neuroprotective abilities of NGF has led to a renewed interest in NGF as a therapeutic for retinal and choroidal diseases. NGF can promote cell proliferation through actions of the TrkA receptor or promote apoptosis through receptor p75NTR. This understanding has led to novel interest in the role of NGF for diseases of the posterior eye. The role of β-adrenergic receptor agonists and antagonists for treatments of glaucoma, diabetic retinopathy, and their potential mechanisms of action, are still under investigation. This review discusses the current knowledge and applications of topical NGF and adrenergic receptor drugs for ocular disease. PMID:20668722

  16. Keratinocyte growth factor induces pancreatic ductal epithelial proliferation.

    PubMed

    Yi, E S; Yin, S; Harclerode, D L; Bedoya, A; Bikhazi, N B; Housley, R M; Aukerman, S L; Morris, C F; Pierce, G F; Ulich, T R

    1994-07-01

    Keratinocyte growth factor (KGF) causes a proliferation of pancreatic ductal epithelial cells in adult rats after daily systemic administration for 1 to 2 weeks. Even before the proliferation of intralobular ducts is histologically evident, KGF also induces proliferating cell nuclear antigen expression within the ductal epithelium of intercalated, intralobular, and interlobular ducts. KGF also causes incorporation of 5-bromodeoxyuridine in ductal epithelial cells. Epithelial cell proliferation is histologically most prominent at the level of the intralobular ducts adjacent to and within the islets of Langerhans. Pancreatic ductal proliferation is not histologically apparent in rats sacrificed 7 to 10 days after the cessation of KGF administration. The pancreatic hormones insulin, glucagon, somatostatin, and pancreatic polypeptide are normally distributed within islets that demonstrate intrainsular ductal proliferation. The proliferating ductal epithelium does not show endocrine differentiation as evidenced by the lack of immunoreactivity for pancreatic hormones. KGF is a potent in vivo mitogen for pancreatic ductal epithelial cells.

  17. Fibroblast Growth Factors in the Gastrointestinal Tract: Twists and Turns.

    PubMed

    Danopoulos, Soula; Schlieve, Christopher R; Grikscheit, Tracy C; Al Alam, Denise

    2017-02-15

    Fibroblast growth factors (FGFs) are a family of conserved peptides that play an important role in the development, homeostasis, and repair processes of many organ systems, including the gastrointestinal tract. All four FGF receptors and several FGF ligands are present in the intestine. They play important roles in controlling cell proliferation, differentiation, epithelial cell restitution, and stem cell maintenance. Several FGFs have also been proven to be protective against gastrointestinal diseases such as inflammatory bowel diseases or to aid in regeneration after intestinal loss associated with short bowel syndrome. Herein, we review the multifaceted actions of canonical FGFs in intestinal development, homeostasis, and repair in rodents and humans. Developmental Dynamics, 2017. © 2017 Wiley Periodicals, Inc.

  18. Fibroblast Growth Factor Signaling in the Developing Neuroendocrine Hypothalamus

    PubMed Central

    Tsai, Pei-San; Brooks, Leah R.; Rochester, Johanna R.; Kavanaugh, Scott I.; Chung, Wilson C. J.

    2011-01-01

    Fibroblast growth factor (FGF) signaling is pivotal to the formation of numerous central regions. Increasing evidence suggests FGF signaling also directs the development of the neuroendocrine hypothalamus, a collection of neuroendocrine neurons originating primarily within the nose and the ventricular zone of the diencephalon. This review outlines evidence for a role of FGF signaling in the prenatal and postnatal development of several hypothalamic neuroendocrine systems. The emphasis is placed on the nasally derived gonadotropin- releasing hormone neurons, which depend on neurotrophic cues from FGF signaling throughout the neurons' lifetime. Although less is known about neuroendocrine neurons derived from the diencephalon, recent studies suggest they also exhibit variable levels of dependence on FGF signaling. Overall, FGF signaling provides a broad spectrum of cues that ranges from genesis, cell survival/death, migration, morphological changes, to hormone synthesis in the neuroendocrine hypothalamus. Abnormal FGF signaling will deleteriously impact multiple hypothalamic neuroendocrine systems, resulting in the disruption of diverse physiological functions. PMID:21129392

  19. Epidermal growth factor receptor-targeted therapy for pancreatic cancer.

    PubMed

    Xiong, Henry Q; Abbruzzese, James L

    2002-10-01

    Epidermal growth factor receptor (EGFR) plays an important role in tumor development and maintenance. It is a cell surface molecule that mediates signal transduction from the cell surface to cytoplasm. Elevated expression of EGFR or its ligand correlates with worse prognosis in a variety of human cancers. Therefore, blockade of EGFR activity would provide a novel strategy for the treatment of cancer. Two classes of EGFR inhibitors, monoclonal antibodies and tyrosine kinase inhibitors, have been described. The preclinical activity of these EGFR inhibitors and phase I clinical data are summarized in this article. A phase II trial of the EGFR inhibitor IMC-C225 in combination with gemcitabine for patients with advanced pancreatic cancer is discussed. Copyright 2002, Elsevier Science (USA). All rights reserved.

  20. Cell and molecular biology of epidermal growth factor receptor.

    PubMed

    Ceresa, Brian P; Peterson, Joanne L

    2014-01-01

    The epidermal growth factor receptor (EGFR) has been one of the most intensely studied cell surface receptors due to its well-established roles in developmental biology, tissue homeostasis, and cancer biology. The EGFR has been critical for creating paradigms for numerous aspects of cell biology, such as ligand binding, signal transduction, and membrane trafficking. Despite this history of discovery, there is a continual stream of evidence that only the surface has been scratched. New ways of receptor regulation continue to be identified, each of which is a potential molecular target for manipulating EGFR signaling and the resultant changes in cell and tissue biology. This chapter is an update on EGFR-mediated signaling, and describes some recent developments in the regulation of receptor biology.

  1. Proteasome Inhibition by Fellutamide B Induces Nerve Growth Factor Synthesis

    PubMed Central

    Hines, John; Groll, Michael; Fahnestock, Margaret; Crews, Craig M.

    2008-01-01

    SUMMARY Neurotrophic small molecules have the potential to aid in the treatment of neuronal injury and neurodegenerative diseases. The natural product fellutamide B, originally isolated from Penicillium fellutanum, potently induces nerve growth factor (NGF) release from fibroblasts and glial-derived cells, although the mechanism for this neurotrophic activity has not been elucidated. Here, we report that fellutamide B potently inhibits proteasome catalytic activity. High resolution structural information obtained from co-crystallization of the 20S proteasome reveals novel aspects regarding β-subunit binding and adduct formation by fellutamide B to inhibit their hydrolytic activity. We demonstrate that fellutamide B and other proteasome inhibitors increased NGF gene transcription via a cis-acting element (or elements) in the promoter. These results demonstrate an unrecognized connection between proteasome inhibition and NGF production, suggesting a possible new strategy in the development of neurotrophic agents. PMID:18482702

  2. Nerve growth factor: stimulation of polymorphonuclear leukocyte chemotaxis in vitro.

    PubMed Central

    Gee, A P; Boyle, M D; Munger, K L; Lawman, M J; Young, M

    1983-01-01

    Topical application of mouse nerve growth factor (NGF) to superficial skin wounds of mice has previously been shown to accelerate the rate of wound contraction. Results of the present study reveal that NGF in the presence of plasma is also chemotactic for human polymorphonuclear leukocytes in vitro, and the concentration of NGF required for this effect is similar to that which stimulates ganglionic neurite outgrowth. This property does not arise from liberation of the C5a fragment of complement, nor does it require the known enzymic activity of NGF. (NGF inactivated with diisopropyl fluorophosphate is equally active.) We conclude that NGF can display biological effects on cells of nonneural origin and function, and this feature might play a role in the early inflammatory response to injury. PMID:6580641

  3. The epidermal growth factor receptor family: Biology driving targeted therapeutics

    PubMed Central

    Wieduwilt, M. J.; Moasser, M. M.

    2011-01-01

    The epidermal growth factor family of receptor tyrosine kinases (ErbBs) plays essential roles in regulating cell proliferation, survival, differentiation and migration. The ErbB receptors carry out both redundant and restricted functions in mammalian development and in the maintenance of tissues in the adult mammal. Loss of regulation of the ErbB receptors underlies many human diseases, most notably cancer. Our understanding of the function and complex regulation of these receptors has fueled the development of targeted therapeutic agents for human malignancies in the last 15 years. Here we review the biology of ErbB receptors, including their structure, signaling, regulation, and roles in development and disease, then briefly touch on their increasing roles as targets for cancer therapy. PMID:18259690

  4. Fibroblast growth factor signaling in skeletal development and disease

    PubMed Central

    Ornitz, David M.; Marie, Pierre J.

    2015-01-01

    Fibroblast growth factor (FGF) signaling pathways are essential regulators of vertebrate skeletal development. FGF signaling regulates development of the limb bud and formation of the mesenchymal condensation and has key roles in regulating chondrogenesis, osteogenesis, and bone and mineral homeostasis. This review updates our review on FGFs in skeletal development published in Genes & Development in 2002, examines progress made on understanding the functions of the FGF signaling pathway during critical stages of skeletogenesis, and explores the mechanisms by which mutations in FGF signaling molecules cause skeletal malformations in humans. Links between FGF signaling pathways and other interacting pathways that are critical for skeletal development and could be exploited to treat genetic diseases and repair bone are also explored. PMID:26220993

  5. Hepatocyte growth factor (HGF) and hemodialysis: physiopathology and clinical implications.

    PubMed

    Libetta, Carmelo; Esposito, Pasquale; Martinelli, Claudia; Grosjean, Fabrizio; Gregorini, Marilena; Rampino, Teresa; Dal Canton, Antonio

    2016-06-01

    Hepatocyte growth factor (HGF) is a pleiotropic cytokine which exerts a variety of effects on several cells, being involved in the regulation of many biological processes, such as inflammation, tissue repair, morphogenesis, angiogenesis, tumour propagation, immunomodulation of viral infections and cardio-metabolic activities. Patients undergoing regular hemodialysis (HD) present elevated levels of HGF, mainly due to the leukocyte activation associated with HD treatment. High HGF levels might account for specific clinical features of HD patients, i.e. mild liver damage in course of HCV-infection and high cardiovascular risk profile. Moreover, in patients with acute kidney injury, the induction of HGF may represent a crucial step to promote renal recovery, which can have important prognostic consequences in the short and long-term. In this review we discuss the mechanisms underlying HGF production in HD patients, the role of HGF in this particular patient population and the potential clinical implications derived from the study of HGF in HD patients.

  6. Circulation a key factor in Mediterranean algal growth

    NASA Astrophysics Data System (ADS)

    Orwig, Jessica

    2014-12-01

    The early appearance of nitrate in December appears to have been the driving force for favorable conditions for algal blooms in the Mediterranean, a new study indicates. To better understand the role of nutrients' availability to enable the growth of phytoplankton in temperate seas, D'Ortenzio et al. installed nitrate concentration sensors on two profiling floats in the northwestern Mediterranean basin in summer 2011. Each spring, the phytoplankton in this basin rapidly grow to form a bloom that blankets the surface and contributes to the transport of carbon from the atmosphere to the deep ocean. Scientists are still unsure exactly what produces the conditions for these blooms, but they know that the availability of nutrients, induced by large-scale circulation in the oceans, during the winter is a factor.

  7. Fibroblast growth factor 21: from pharmacology to physiology.

    PubMed

    Kliewer, Steven A; Mangelsdorf, David J

    2010-01-01

    Fibroblast growth factor 21 (FGF21) is an atypical member of the FGF family that functions as an endocrine hormone. Pharmacologic studies show that FGF21 has broad metabolic actions in obese rodents and primates that include enhancing insulin sensitivity, decreasing triglyceride concentrations, and causing weight loss. In lean rodents, FGF21 expression is strongly induced in liver by prolonged fasting through a mechanism that involves the nuclear receptor peroxisome proliferator-activated receptor alpha. FGF21, in turn, induces the transcriptional coactivator protein peroxisome proliferator-activated receptor gamma coactivator protein 1alpha and stimulates hepatic gluconeogenesis, fatty acid oxidation, and ketogenesis. FGF21 also blocks somatic growth and sensitizes mice to a hibernation-like state of torpor. Thus, FGF21 plays a key role in eliciting and coordinating the adaptive starvation response. Interestingly, FGF21 expression is induced in white adipose tissue by peroxisome proliferator-activated receptor gamma, which suggests that it also regulates metabolism in the fed state. This article highlights recent advances in our understanding of FGF21's pharmacologic and physiologic actions.

  8. Mechanisms of fibroblast growth factor signaling in the ovarian follicle.

    PubMed

    Price, Christopher A

    2016-02-01

    Fibroblast growth factors (FGFs) have been shown to alter growth and differentiation of reproductive tissues in a variety of species. Within the female reproductive tract, the effects of FGFs have been focused on the ovary, and the most studied one is FGF2, which stimulates granulosa cell proliferation and decreases differentiation (decreased steroidogenesis). Other FGFs have also been implicated in ovarian function, and this review summarizes the effects of members of two subfamilies on ovarian function; the FGF7 subfamily that also contains FGF10, and the FGF8 subfamily that also contains FGF18. There are data to suggest that FGF8 and FGF18 have distinct actions on granulosa cells, despite their apparent similar receptor binding properties. Studies of non-reproductive developmental biology also indicate that FGF8 is distinct from FGF18, and that FGF7 is also distinct from FGF10 despite similar receptor binding properties. In this review, the potential mechanisms of differential action of FGF7/FGF10 and FGF8/FGF18 during organogenesis will be reviewed and placed in the context of follicle development. A model is proposed in which FGF8 and FGF18 differentially activate receptors depending on the properties of the extracellular matrix in the follicle. © 2016 Society for Endocrinology.

  9. Manipulation of the nerve growth factor network in prostate cancer.

    PubMed

    Papatsoris, Athanasios G; Liolitsa, Danae; Deliveliotis, Charalambos

    2007-03-01

    Autocrine and paracrine events regulated by nerve growth factor (NGF) and relevant receptors (low- and high affinity; p75 neurotrophin receptor [p75(NTR)] and TrkA, respectively) seem to play a significant role in prostate carcinogenesis. Studies reveal that p75(NTR) is both a tumor suppressor of growth and a metastasis suppressor of human prostate cancer cells. Furthermore, p75(NTR) is progressively lost during prostate carcinogenesis. An imbalance between p75(NTR) and tropomyosin receptor kinase A (TrkA)-mediated signals may be involved in the progression of prostate cancer through increased proliferation and reduced apoptosis. The antiproliferative and apoptotic effects of GnRH analogs in prostate cancer cells may be mediated by altering the TrkA:p75(NTR) NGF receptor ratio. Administration of NGF induces a reversion of the androgen-independent/androgen receptor-negative prostate cancer cell lines to a less malignant phenotype. Finally, Trk inhibition is a novel, attractive and rational approach for prostate cancer therapy. This review unravels the NGF 'circuitry' in prostate cancinogenesis for relevant pharmacologic manipulation to lead to the development of novel therapeutic agents.

  10. Aqueous stability of human epidermal growth factor 1-48.

    PubMed

    Senderoff, R I; Wootton, S C; Boctor, A M; Chen, T M; Giordani, A B; Julian, T N; Radebaugh, G W

    1994-12-01

    Human epidermal growth factor 1-48 (hEGF 1-48, Des(49-53)hEGF) is a single chain polypeptide (48 amino acids; 3 disulfide bonds; 5445 Da) possessing a broad spectrum of biologic activity including the stimulation of cell proliferation and tissue growth. In this study, three primary aqueous degradation products of hEGF 1-48 were isolated using isocratic, reverse phase/ion-pair HPLC. The degradation products were characterized using amino acid sequencing, electrospray ionization mass spectrometry, isoelectric focusing, and degradation kinetics. Results indicate that hEGF 1-48 degrades via oxidation (Met21), deamidation (Asn1), and succinimide formation (Asp11). The relative contribution of each degradation pathway to the overall stability of hEGF 1-48 changes as a function of solution pH and storage condition. Succinimide formation at Asp11 is favored at pH < 6 in which aspartic acid is present mostly in its protonated form. Deamidation of Asn1 is favored at pH > 6. The relative contribution of Met21 oxidation is increased with decreasing temperature, storage as a frozen solution (-20 degrees C), and exposure to fluorescent light.

  11. Upregulation of nerve growth factor following cortical trauma.

    PubMed

    DeKosky, S T; Goss, J R; Miller, P D; Styren, S D; Kochanek, P M; Marion, D

    1994-12-01

    As part of the inflammatory response to brain injury, CSF and tissue levels of interleukin-1 beta (IL-1 beta) are elevated after trauma. This elevation in IL-1 beta initiates a cascade of events among which may be an upregulation in nerve growth factor (NGF) in brain tissue. We infused IL-1 beta into the ventricle of adult rats and found a two- to fourfold increase in NGF in the cerebral cortex, hippocampus, and cerebellum, suggesting that IL-1 beta induced in vivo may also increase NGF in the brain. To test this hypothesis we utilized two models of traumatic brain injury (TBI) in the rat and examined NGF protein and RNA in the cortex over a period of several days. Both weight drop and controlled cortical contusion models of CNS trauma demonstrated large and significant increases in NGF protein in the cortex. NGF RNA was assessed in the controlled cortical contusion model and increased approximately fivefold by 1 day post-trauma. The remarkable elevation of NGF observed following TBI suggests that its role in response to injury may be other than as a target-derived growth substance. We hypothesize that the elevation of NGF in trauma induces upregulation of enzymes which suppress free-radical formation after injury.

  12. Epidermal growth factor and its receptors in human pancreatic carcinoma

    SciTech Connect

    Chen, Y.F.; Pan, G.Z.; Hou, X.; Liu, T.H.; Chen, J.; Yanaihara, C.; Yanaihara, N. )

    1990-05-01

    The role of epidermal growth factor (EGF) in oncogenesis and progression of malignant tumors is a subject of vast interest. In this study, radioimmunoassay and radioreceptor assay of EGF were established. EGF contents in malignant and benign pancreatic tumors, in normal pancreas tissue, and in culture media of a human pancreatic carcinoma cell line were determined. EGF receptor binding studies were performed. It was shown that EGF contents in pancreatic carcinomas were significantly higher than those in normal pancreas or benign pancreatic tumors. EGF was also detected in the culture medium of a pancreatic carcinoma cell line. The binding of 125I-EGF to the pancreatic carcinoma cells was time and temperature dependent, reversible, competitive, and specific. Scatchard analysis showed that the dissociation constant of EGF receptor was 2.1 X 10(-9) M, number of binding sites was 1.3 X 10(5) cell. These results indicate that there is an over-expression of EGF/EGF receptors in pancreatic carcinomas, and that an autocrine regulatory mechanism may exist in the growth-promoting effect of EGF on tumor cells.

  13. Insulin-like growth factor I: a biologic maturation indicator.

    PubMed

    Ishaq, Ramy Abdul Rahman; Soliman, Sanaa Abou Zeid; Foda, Manal Yehya; Fayed, Mona Mohamed Salah

    2012-11-01

    Determination of the maturation level and the subsequent evaluation of growth potential during preadolescence and adolescence are important for optimal orthodontic treatment planning and timing. This study was undertaken to evaluate the applicability of insulin-like growth factor I (IGF-I) blood level as a maturation indicator by correlating it to the cervical vertebral maturation index. The study was conducted with 120 subjects, equally divided into 60 males (ages, 10-18 years) and 60 females (ages, 8-16 years). A lateral cephalometric radiograph and a blood sample were taken from each subject. For each subject, cervical vertebral maturation and IGF-I serum level were assessed. Mean values of IGF-I in each stage of cervical vertebral maturation were calculated, and the means in each stage were statistically compared with those of the other stages. The IGF-I mean value at each cervical vertebral maturation stage was statistically different from the mean values at the other stages. The highest mean values were observed in stage 4, followed by stage 5 in males and stage 3 in females. IGF-I serum level is a reliable maturation indicator that could be applied in orthodontic diagnosis. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  14. Epidermal growth factor receptor activation in developing rat kidney.

    PubMed

    Cybulsky, A V; Goodyer, P R; McTavish, A J

    1994-09-01

    Epidermal growth factor (EGF) binding increases in late-gestational rat kidney and then falls toward basal adult levels postnatally during the 1st wk. We report that the increase in EGF binding is accompanied by an increase in EGF receptor (EGFR) protein and activation of EGFR tyrosine kinase. Multiple proteins were endogenously tyrosine phosphorylated in kidney membranes from fetal rats, and the phosphorylation pattern was similar in rats ranging from 16 to 21 days of gestation. Tyrosine phosphorylation was, however, almost undetectable in 12-wk adult rat kidneys (controls). Among the phosphoproteins in fetal kidney, a prominent 170-kDa protein was identified as EGFR. Endogenous tyrosine phosphorylation of EGFR (reflecting receptor activation) was 30-fold higher in fetal kidney membranes than in adult (3- to 7-fold higher when adjusted for differences in EGF binding or EGFR protein content). The EGFR substrate, phospholipase C-gamma 1, was tyrosine phosphorylated in fetal kidneys but not adult, and a greater proportion was membrane-associated in fetal kidneys, consistent with activation of phospholipase C-gamma 1. Thus EGFR tyrosine kinase activity is increased in late-gestational rat kidney. Induction and activation of EGFR may mediate perinatal renal cell growth and development.

  15. Nerve growth factor signaling in prostate health and disease.

    PubMed

    Arrighi, Nicola; Bodei, Serena; Zani, Danilo; Simeone, Claudio; Cunico, Sergio Cosciani; Missale, Cristina; Spano, Pierfranco; Sigala, Sandra

    2010-06-01

    The prostate is one of the most abundant sources of nerve growth factor (NGF) in different species, including humans. NGF and its receptors are implicated in the control of prostate cell proliferation and apoptosis and it can either support or suppress cell growth. The co-expression of both NGF receptors, p75(NGFR) and tropomyosin-related kinase A (trkA), represents a crucial condition for the antiproliferative effect of NGF; indeed, p75(NGFR) is progressively lost during prostate tumorigenesis and its disappearance represents a malignancy marker of prostate adenocarcinoma (PCa). Interestingly, a dysregulation of NGF signal transduction was found in a number of human tumors. This review summarizes the current knowledge on the role of NGF and its receptors in prostate and in PCa. Conclusions bring to the hypothesis that the NGF network could be a candidate for future pharmacological manipulation in the PCa therapy: in particular the re-expression of p75(NTR) and/or the negative modulation of trkA could represent a target to induce apoptosis and to reduce proliferation and invasiveness of PCa.

  16. Fibroblast growth factor is an inhibitor of chondrocyte terminal differentiation

    SciTech Connect

    Kato, Y.; Iwamoto, M. )

    1990-04-05

    The effects of basic fibroblast growth factor (bFGF) on terminal differentiation of chondrocytes and cartilage-matrix calcification were investigated. Rabbit growth-plate chondrocytes maintained as a pelleted mass in a centrifuge tube produced an abundant proteoglycan matrix during the matrix-maturation stage, yielding a cartilage-like tissue. Thereafter, they terminally differentiated to hypertrophic chondrocytes which produced high levels of alkaline phosphatase. These cells induced extensive calcification of the matrix in the absence of additional phosphate. Addition of bFGF to the chondrocyte cultures abolished the increases in alkaline phosphatase activity, {sup 45}Ca deposition, and the calcium content. These effects were dose-dependent, reversible, and observed in the presence of cytosine arabinoside, an inhibitor of DNA synthesis. The inhibitory effects could be observed only when chondrocytes were exposed to bFGF in a transition period between the matrix-maturation and hypertrophic stages. As chondrocytes differentiated to hypertrophic cells, bFGF became less effective in inhibiting the expression of the mineralization-related phenotypes. The present study also shows that although the rate of ({sup 35}S)sulfate incorporation into large, chondroitin sulfate proteoglycan in the cell-matrix fraction is very high during the matrix-maturation stage, it abruptly decreases by 90% after terminal differentiation. Furthermore, the terminal differentiation-associated decrease in proteoglycan synthesis was delayed by bFGF. These results provide evidence that bFGF inhibits terminal differentiation of chondrocytes and calcification.

  17. Structural basis for agonism and antagonism of hepatocyte growth factor

    SciTech Connect

    Tolbert, W. David; Daugherty-Holtrop, Jennifer; Gherardi, Ermanno; Vande Woude, George; Xu, H. Eric

    2010-11-01

    Hepatocyte growth factor (HGF) is an activating ligand of the Met receptor tyrosine kinase, whose activity is essential for normal tissue development and organ regeneration but abnormal activation of Met has been implicated in growth, invasion, and metastasis of many types of solid tumors. HGF has two natural splice variants, NK1 and NK2, which contain the N-terminal domain (N) and the first kringle (K1) or the first two kringle domains of HGF. NK1, which is a Met agonist, forms a head-to-tail dimer complex in crystal structures and mutations in the NK1 dimer interface convert NK1 to a Met antagonist. In contrast, NK2 is a Met antagonist, capable of inhibiting HGF's activity in cell proliferation without clear mechanism. Here we report the crystal structure of NK2, which forms a 'closed' monomeric conformation through interdomain interactions between the N- domain and the second kringle domain (K2). Mutations that were designed to open up the NK2 closed conformation by disrupting the N/K2 interface convert NK2 from a Met antagonist to an agonist. Remarkably, this mutated NK2 agonist can be converted back to an antagonist by a mutation that disrupts the NK1/NK1 dimer interface. These results reveal the molecular determinants that regulate the agonist/antagonist properties of HGF NK2 and provide critical insights into the dimerization mechanism that regulates the Met receptor activation by HGF.

  18. Anti-Epidermal Growth Factor Receptor Gene Therapy for Glioblastoma

    PubMed Central

    Hicks, Martin J.; Chiuchiolo, Maria J.; Ballon, Douglas; Dyke, Jonathan P.; Aronowitz, Eric; Funato, Kosuke; Tabar, Viviane; Havlicek, David; Fan, Fan; Sondhi, Dolan; Kaminsky, Stephen M.; Crystal, Ronald G.

    2016-01-01

    Glioblastoma multiforme (GBM) is the most common and aggressive primary intracranial brain tumor in adults with a mean survival of 14 to 15 months. Aberrant activation of the epidermal growth factor receptor (EGFR) plays a significant role in GBM progression, with amplification or overexpression of EGFR in 60% of GBM tumors. To target EGFR expressed by GBM, we have developed a strategy to deliver the coding sequence for cetuximab, an anti-EGFR antibody, directly to the CNS using an adeno-associated virus serotype rh.10 gene transfer vector. The data demonstrates that single, local delivery of an anti-EGFR antibody by an AAVrh.10 vector coding for cetuximab (AAVrh.10Cetmab) reduces GBM tumor growth and increases survival in xenograft mouse models of a human GBM EGFR-expressing cell line and patient-derived GBM. AAVrh10.CetMab-treated mice displayed a reduction in cachexia, a significant decrease in tumor volume and a prolonged survival following therapy. Adeno-associated-directed delivery of a gene encoding a therapeutic anti-EGFR monoclonal antibody may be an effective strategy to treat GBM. PMID:27711187

  19. Autologous blood preparations rich in platelets, fibrin and growth factors

    PubMed Central

    FIORAVANTI, C.; FRUSTACI, I.; ARMELLIN, E.; CONDÒ, R.; ARCURI, C.; CERRONI, L.

    2015-01-01

    SUMMARY Objectives Bone regeneration is often needed prior to dental implant treatment due to the lack of adequate quantity and quality after infectious diseases. The greatest regenerative power was obtained with autologous tissue, primarily the bone alive, taken from the same site or adjacent sites, up to the use centrifugation of blood with the selection of the parts with the greatest potential regenerative. In fact, various techniques and technologies were chronologically successive to cope with an ever better preparation of these concentrates of blood. Our aim is to review these advances and discuss the ways in which platelet concentrates may provide such unexpected beneficial therapeutic effects. Methods The research has been carried out in the MEDLINE and Cochrane Central Register of Controlled Trials database by choosing keywords as “platelet rich plasma”, “platelet rich fibrin”, “platelet growth factors”, and “bone regeneration” and “dentistry”. Results Autologous platelet rich plasma is a safe and low cost procedure to deliver growth factors for bone and soft tissue healing. Conclusion The great heterogeneity of clinical outcomes can be explained by the different PRP products with qualitative and quantitative difference among substance. PMID:28042422

  20. [Epidermal growth factor receptor expression and epidermal growth factor blood plasma content in simple and complex endometrial hyperplasia].

    PubMed

    Dznelashvili, N; Kasradze, D; Tavartkiladze, A; Mariamidze, A

    2014-01-01

    The goal of our study was to concurrently determine the prognostic significance of Epidermal Growth Factor Receptor (EGFR) expression in endometrium and Epidermal Growth Factor (EGF) blood content in simple and complex hyperplasia. In order to detect EGFR expression, immunohistochemical examination of endometrial scarp from 35 patients was done along with HPLC (High performance liquid chromatography) method, for measuring EGF blood plasma content. The numerical data obtained were processed statistically using computer program SPSS-12. According to the results: 1. A significant/marked increase in EGF blood plasma level together with pronounced EGFR expression in simple endometrial hyperplasia (without atypia) suggests that simple hyperplasia is likely to transform into complex form, while unchanged level of EGF against the background of mild EGFR expression is probably indicative of not very bad prognosis. 2. Normal indices of EGF blood plasma level in simple endometrial hyperplasia (without atypia), accompanied by mild EGFR expression is suggestive of good prognosis. 3. A sharp or extremely sharp increase in EGF blood plasma level with pronounced EGFR expression in complex endometrial hyperplasia (without atypia) is likely to indicate poor prognosis that may lead to the transformation into atypical form. However, unchanged EGF blood plasma level against the background of mild EGFR expression in complex endometrial hyperplasia (without atypia) is likely to point to not very bad prognosis. 4. A marked increase in EGF blood plasma level with a pronounced EGFR expression in complex endometrial hyperplasia (without atypia) is likely to indicate poor prognosis that may lead to the transformation into atypical form. Because it is evident that drastic increase in EGF blood plasma level is not necessary, other factor should be suspected to play the major role, i.e the substance that will (or will not) withstand neoplasia.

  1. Placental growth factor and vascular endothelial growth factor serum levels in Tunisian Arab women with suspected preeclampsia.

    PubMed

    Ben Ali Gannoun, Marwa; Bourrelly, Séverine; Raguema, Nozha; Zitouni, Hedia; Nouvellon, Eva; Maleh, Wided; Brahim Chemili, Afraa; Elfeleh, Raja; Almawi, Wassim; Mahjoub, Touhami; Gris, Jean-Christophe

    2016-03-01

    The angiogenic factors vascular endothelial growth factor (VEGF) and placental growth factor (PIGF) play a central role in the process of angiogenesis. We evaluated the association of free PIGF and free VEGF levels and the risk of preeclampsia (PE) among Tunisian Arab women, and established the range of VEGF and PIGF in normal healthy pregnancies, between 24 and 42weeks of gestation. This retrospective case-control study included 345 women with PE, and 289 women with uncomplicated pregnancies. PIGF and VEGF plasma levels were quantitated by commercially-available ELISA. Compared to control women, plasma PIGF concentrations were lower in women with PE at all gestation age intervals (P<0.0001), compared to VEGF levels which were significantly lower in women with PE but only during early gestation age intervals ([29-32[ and [32-35[). High odds for developing PE, and correspondingly higher associations, were associated with low PIGF values (less than the 5(th) percentile), at all gestation age intervals. The only exception was recorded for the [29-32 [interval, which was not statistically significant. PIGF testing, recorded at 29-37weeks of gestation, had a higher specificity (93-100%) than sensitivity, and the positive predictive values ranged from 90% to 100% for 24-37weeks of gestation. This indicates that it mainly detects non-PE healthy women as well, and thus may be useful as a screening test, though currently unreliable for diagnostic purposes. Reduced PIGF levels during different gestation age intervals, and reduced VEGF levels during early gestation age intervals are also associated with subsequent development of PE in our population; the gestational age interval adjusted-5(th) percentiles of PIGF provide reference ranges for this marker in normal pregnancy.

  2. Chicken stem cell factor enhances primordial germ cell proliferation cooperatively with fibroblast growth factor 2

    PubMed Central

    MIYAHARA, Daichi; OISHI, Isao; MAKINO, Ryuichi; KURUMISAWA, Nozomi; NAKAYA, Ryuma; ONO, Tamao; KAGAMI, Hiroshi; TAGAMI, Takahiro

    2015-01-01

    An in vitro culture system of chicken primordial germ cells (PGCs) has been recently developed, but the growth factor involved in the proliferation of PGCs is largely unknown. In the present study, we investigated the growth effects of chicken stem cell factor (chSCF) on the in vitro proliferation of chicken PGCs. We established two feeder cell lines (buffalo rat liver cells; BRL cells) that stably express the putative secreted form of chSCF (chSCF1-BRL) and membrane bound form of chSCF (chSCF2-BRL). Cultured PGC lines were incubated on chSCF1 or chSCF2-BRL feeder cells with fibroblast growth factor 2 (FGF2), and growth effects of each chSCF isoform were investigated. The in vitro proliferation rate of the PGCs cultured on chSCF2-BRL at 20 days of culture was more than threefold higher than those cultured on chSCF1-BRL cells and more than fivefold higher than those cultured on normal BRL cells. Thus, use of chSCF2-BRL feeder layer was effective for in vitro proliferation of chicken PGCs. However, the acceleration of PGC proliferation on chSCF2-BRL was not observed without FGF2, suggesting that chSCF2 would act as a proliferation co-factor of FGF2. We transferred the PGCs cultured on chSCF2-BRL cells to recipient embryos, generated germline chimeric chickens and assessed the germline competency of cultured PGCs by progeny test. Donor-derived progenies were obtained, and the frequency of germline transmission was 3.39%. The results of this study demonstrate that chSCF2 induces hyperproliferation of chicken PGCs retaining germline competency in vitro in cooperation with FGF2. PMID:26727404

  3. Epidermal growth factor-stimulated protein phosphorylation in rat hepatocytes

    SciTech Connect

    Connelly, P.A.; Sisk, R.B.; Johnson, R.M.; Garrison, J.C.

    1987-05-01

    Epidermal growth factor (EGF) causes a 6-fold increase in the phosphorylation state of a cytosolic protein (pp36, M/sub r/ = 36,000, pI = 5.5) in hepatocytes isolated from fasted, male, Wistar rats. Stimulation of /sup 32/P incorporation is observed as early as 1 min following treatment of hepatocytes with EGF and is still present at 30 min after exposure to the growth factor. The phosphate incorporated into pp36 in response to EGF is located predominantly in serine but not tyrosine residues. Phosphorylation of pp36 does not occur in response to insulin or to agents which specifically activate the cAMP-dependent protein kinase (S/sub p/ -cAMPS), protein kinase C (PMA) or Ca/sup 2 +//calmodulin-dependent protein kinases (A23187) in these cells. Prior treatment of hepatocytes with the cAMP analog, S/sub p/-cAMPS, or ADP-ribosylation of N/sub i/, the inhibitory GTP-binding protein of the adenylate cyclase complex, does not prevent EGF-stimulated phosphorylation of pp36. However, as seen in other cell types, pretreatment of hepatocytes with PMA abolishes all EGF-mediated responses including phosphorylation of pp36. These results suggest that EGP specifically activates an uncharacterized, serine protein kinase in hepatocytes that is distal to the intrinsic EGF receptor tyrosine protein kinase. The rapid activation of this kinase suggests that it may play an important role in the early response of the cell to EGF.

  4. Growth Differentiation Factor 15 Predicts Chronic Liver Disease Severity

    PubMed Central

    Lee, Eaum Seok; Kim, Seok Hyun; Kim, Hyun Jin; Kim, Kyung Hee; Lee, Byung Seok; Ku, Bon Jeong

    2017-01-01

    Background/Aims Growth differentiation factor 15 (GDF-15) belongs to the transforming growth factor-β superfamily. GDF-15 is emerging as a biomarker for several diseases. The aim of this study was to determine the clinical performances of GDF-15 for the prediction of liver fibrosis and severity in chronic liver disease. Methods The serum GDF-15 levels were examined via enzyme immunoassay in 145 patients with chronic liver disease and 101 healthy individuals. The patients with chronic liver disease consisted of 54 patients with chronic hepatitis, 44 patients with compensated liver cirrhosis, and 47 patients with decompensated liver cirrhosis. Results Of the patients with chronic liver diseases, the decompensated liver cirrhosis patients had an increased serum GDF-15 (3,483 ng/L) level compared with the patients with compensated liver cirrhosis (1,861 ng/L) and chronic hepatitis (1,232 ng/L). The overall diagnostic accuracies of GDF-15, as determined by the area under the receiver operating characteristic curves, were as follows: chronic hepatitis=0.656 (>574 ng/L, sensitivity, 53.7%; specificity, 79.2%), compensated liver cirrhosis=0.886 (>760 ng/L, sensitivity, 75.6%; specificity, 92.1%), and decompensated liver cirrhosis=0.984 (>869 ng/L, sensitivity, 97.9%; specificity, 94.1%). Conclusions This investigation represents the first study to demonstrate the availability of GDF-15 in chronic liver disease. GDF-15 comprised a useful biomarker for the prediction of liver fibrosis and severity in chronic liver disease. PMID:27728964

  5. Fibroblast Growth Factor-23—A Potential Uremic Toxin

    PubMed Central

    Kuczera, Piotr; Adamczak, Marcin; Wiecek, Andrzej

    2016-01-01

    Fibroblast growth factor-23 (FGF23) is a circulating member of the FGF family produced mainly by the osteocytes and osteoblasts that can act as a hormone. The main action of FGF23 is to lower phosphatemia via the reduction of urinary phosphate reabsorption and the decrease of 1,25(OH)2-D generation in the kidney. In the course of chronic kidney disease (CKD), plasma FGF23 concentration rises early, most probably to compensate the inability of the deteriorating kidneys to excrete an adequate amount of phosphate. However, this comes at the cost of FGF23-related target organ toxicity. Results of clinical studies suggest that elevated plasma FGF23 concentration is independently associated with the increased risk of CKD progression, occurrence of cardio-vascular complications, and mortality in different stages of CKD. FGF23 also contributes to cardiomyocyte hypertrophy, vascular calcification, and endothelial dysfunction. The impact of FGF23 on heart muscle is not dependent on Klotho, but rather on the PLCγ–calcineurin–NFAT (nuclear factor of activated T-cells) pathway. Among the factors increasing plasma FGF23 concentration, active vitamin D analogues play a significant role. Additionally, inflammation and iron deficiency can contribute to the increase of plasma FGF23. Among the factors decreasing plasma FGF23, dietary phosphate restriction, some intestinal phosphate binders, cinacalcet (and other calcimimetics), and nicotinamide can be enumerated. Anti-FGF23 antibodies have also recently been developed to inhibit the action of FGF23 in target organs. Still, the best way to normalize plasma FGF23 in maintenance hemodialysis patients is restoring kidney function by successful kidney transplantation. PMID:27941640

  6. Hepatocyte Growth Factor Regulates Angiotensin Converting Enzyme Expression*

    PubMed Central

    Day, Regina M.; Thiel, Gerald; Lum, Julie; Chévere, Rubén D.; Yang, Yongzhen; Stevens, Joanne; Sibert, Laura; Fanburg, Barry L.

    2008-01-01

    Hepatocyte growth factor (HGF) is a mitogen, morphogen, and motogen that functions in tissue healing and acts as an anti-fibrotic factor. The mechanism for this is not well understood. Recent studies implicate somatic angiotensin-converting enzyme (ACE) in fibrosis. We examined the effects of HGF on ACE expression in bovine pulmonary artery endothelial cells (BPAEC). Short term treatment of BPAEC with HGF transiently increased both ACE mRNA (3 h) and activity (24 h), as determined by ACE protease assays and reverse transcription-PCR. Incubation of BPAEC with HGF for longer periods suppressed ACE mRNA (6 h) and activity (72 h). In contrast, phorbol ester (PMA) treatment produced sustained increase in ACE mRNA and activity. We examined the short term molecular effects of HGF on ACE using PMA for comparison. HGF and PMA increased transcription from a luciferase reporter with the core ACE promoter, which contains a composite binding site for SP1/3 and Egr-1. Immunocytochemistry and electrophoretic mobility shift assay showed that both HGF and PMA increased Egr-1 binding. HGF also increased SP3 binding, as measured by EMSA. However, HGF and PMA increased the cellular activity of only Egr-1, not SP3, as measured by luciferase reporter assays. Deletion of the Egr-1 site in the reporter construct completely abrogated HGF-induced transcription but only ~50% of PMA-induced activity. Expression of dominant negative Egr-1 and SP3 blocked up-regulation of the ACE promoter by HGF but only reduced up-regulation by PMA. These results show that HGF transiently increases gene transcription of ACE via activation of Egr-1, whereas PMA regulation involves Egr-1 and additional factor(s). PMID:14679188

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

    SciTech Connect

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

    1988-01-05

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

  8. Coregulation of Epidermal Growth Factor Receptor/Human Epidermal Growth Factor Receptor 2 (HER2) Levels and Locations: Quantitative Analysis of HER2 Overexpression Effects

    SciTech Connect

    Hendriks, Bart S.; Opresko, Lee; Wiley, H. S.; Lauffenburger, Douglas A.

    2003-03-01

    Elevated expression of human epidermal growth factor receptor 2 (HER2) is know to alter cell signalilng and behavioral responses implicated in tumor progression. However, multiple diverse mechanisms may be involved in these overall effects, including signaling by HER2 itself, modulation of signalilng by epidermal growth factor receptor (EGFR) and modification of trafficking dynamics for both EGFR and HER2. Continued....

  9. Vascular endothelial growth factor acts as an osteolytic factor in breast cancer metastases to bone

    PubMed Central

    Aldridge, S E; Lennard, T W J; Williams, J R; Birch, M A

    2005-01-01

    Vascular endothelial growth factor (VEGF) is a proangiogenic cytokine that is expressed highly in many solid tumours often correlating with a poor prognosis. In this study, we investigated the expression of VEGF and its receptors in bone metastases from primary human breast tumours and further characterised its effects on osteoclasts in vitro. Breast cancer metastases to bone were immunohistochemically stained for VEGF, its receptors VEGFR1 and 2 (vascular endothelial growth factor receptor 1 and 2), demonstrating that breast cancer metastases express VEGF strongly and that surrounding osteoclasts express both VEGFR1 and VEGFR2. RAW 264.7 cells (mouse monocyte cell line) and human peripheral blood mononuclear cells (PBMCs) were cultured with VEGF, RANKL and M-CSF. VEGF and RANKL together induced differentiation of multinucleated, tartrate-resistant acid phophatase (TRAP)-positive cells in similar numbers to M-CSF and RANKL. The PBMCs were also able to significantly stimulate resorption of mineralised matrix after treatment with M-CSF with RANKL and VEGF with RANKL. We have shown that VEGF in the presence of RANKL supports PBMC differentiation into osteoclast-like cells, able to resorb substrate. Vascular endothelial growth factor may therefore play a role in physiological bone resorption and in pathological situations. Consequently, VEGF signalling may be a therapeutic target for osteoclast inhibition in conditions such as tumour osteolysis. PMID:15812559

  10. 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.

  11. Quercetin inhibits angiogenesis-mediated human retinoblastoma growth by targeting vascular endothelial growth factor receptor.

    PubMed

    Song, Wei; Zhao, Xiaofei; Xu, Jiarui; Zhang, Han

    2017-09-01

    Retinoblastoma (RB) is the most common malignant intraocular cancer in teenagers, occurrence of which depends on the mutation of multiple genes. Among all the signaling pathways involved in the oncogenesis of RB, the process of angiogenesis has been demonstrated to be associated with the local invasive growth and metastasis of this cancer type. Quercetin (Que) is a typical flavonoid and has been reported to inhibit angiogenesis in various types of tumors. In the present study, the effect of Que on RB cells and angiogenesis of RB was evaluated. The human RB Y79 cell line was subjected to treatment with Que of various concentrations. Viability, invasion and migration ability and apoptosis of Y79 cells were subsequently measured to assess the effect of Que on RB cells. In addition, the expression of vascular endothelial growth factor receptor (VEGFR) was also quantified. It was revealed that Que inhibited RB cell growth and invasion in vitro in a dose-dependent manner, with 100 µM Que exhibiting the strongest inhibitory effect. In addition, Que downregulated the expression of VEGFR, which was an indicator of the blockade of angiogenesis in RB by targeting VEGF. The effect of Que on angiogenesis was also observed to be dose-dependent. The results of the present study indicated that Que may be a potential anti-RB therapy due to its anti-angiogenesis effect.

  12. Isoproterenol inhibits fibroblast growth factor-2-induced growth of renal epithelial cells.

    PubMed

    Izevbigie, E B; Gutkind, J S; Ray, P E

    2000-08-01

    The signal transduction pathways modulating bFGF effects in renal tubular epithelial cells (RTEc) are not completely understood. Since the cAMP and the mitogen-activated protein kinase (MAPK) pathways can modulate the growth of RTEc, we studied whether two cAMP elevating agents, isoproterenol and 8-bromo-cAMP, would modulate basic fibroblast growth factor (bFGF) induction of MAPK activity (ERK-2) and cell proliferation in human renal proximal tubular epithelial cells (RPTEc) and Madin-Darby canine kidney cells (MDCK clone EI1). Isoproterenol, but not bFGF, stimulated cAMP production in RPTEc and MDCKEI1 cells. bFGF, isoproterenol, and 8-bromo-cAMP alone increased ERK-2 activity in both cell types. However, isoproterenol and 8-bromo-cAMP partially inhibited the bFGF induction of ERK-2 activity, but only isoproterenol inhibited the proliferation of both cell types. PD098059 (25 microM), an inhibitor of MAPK kinase (MEK 1/2), blocked the bFGF mitogenic effects, but did not affect the 8-bromo-cAMP-induced mitogenic effects in MDCKEI1 cells. These findings suggest that activation of ERK-2 is required but not sufficient for mitogenesis in RTEc. We conclude that isoproterenol inhibits the growth-promoting effects of bFGF in RTEc via MEK-dependent and -independent pathways.

  13. Magnetic fluid hyperthermia inhibits the growth of breast carcinoma and downregulates vascular endothelial growth factor expression.

    PubMed

    Wang, Guihua; Xu, Derong; Chai, Qin; Tan, Xiaolang; Zhang, Yu; Gu, Ning; Tang, Jintian

    2014-05-01

    The application of magnetic fluid hyperthermia (MFH) with nanoparticles has been shown to inhibit tumor growth in several animal models. However, the feasibility of using MFH in vivo to treat breast cancer is uncertain, and the mechanism is unclear. In the present study, it was observed that the intratumoral administration of MFH induced hyperthermia significantly in rats with Walker-265 breast carcinomas. The hyperthermia treatment with magnetic nanoparticles inhibited tumor growth in vivo and promoted the survival of the tumor-bearing rats. Furthermore, it was found that MFH treatment downregulated the protein expression of vascular endothelial growth factor (VEGF) in the tumor tissue, as observed by immunohistochemistry. MFH treatment also decreased the gene expression of VEGF and its receptors, VEGF receptor 1 and 2, and inhibited angiogenesis in the tumor tissues. Taken together, these results indicate that the application of MFH with nanoparticles is feasible for the treatment of breast carcinoma. The MFH-induced downregulation of angiogenesis may also contribute to the induction of an anti-tumor effect.

  14. Abnormal bone growth and selective translational regulation in basic fibroblast growth factor (FGF-2) transgenic mice.

    PubMed Central

    Coffin, J D; Florkiewicz, R Z; Neumann, J; Mort-Hopkins, T; Dorn, G W; Lightfoot, P; German, R; Howles, P N; Kier, A; O'Toole, B A

    1995-01-01

    Basic fibroblast growth factor (FGF-2) is a pleiotropic growth factor detected in many different cells and tissues. Normally synthesized at low levels, FGF-2 is elevated in various pathologies, most notably in cancer and injury repair. To investigate the effects of elevated FGF-2, the human full-length cDNA was expressed in transgenic mice under control of a phosphoglycerate kinase promoter. Overexpression of FGF-2 caused a variety of skeletal malformations including shortening and flattening of long bones and moderate macrocephaly. Comparison by Western blot of FGF-2 transgenic mice to nontransgenic littermates showed expression of human FGF-2 protein in all major organs and tissues examined including brain, heart, lung, liver, kidney, spleen, and skeletal muscle; however, different molar ratios of FGF-2 protein isoforms were observed between different organs and tissues. Some tissues preferentially synthesize larger isoforms of FGF-2 while other tissues produce predominantly smaller 18-kDa FGF-2. Translation of the high molecular weight isoforms initiates from unconventional CUG codons and translation of the 18-kDa isoform initiates from an AUG codon in the FGF-2 mRNA. Thus the Western blot data from the FGF-2 transgenic mice suggest that tissue-specific expression of FGF-2 isoforms is regulated translationally. Images PMID:8590811

  15. Growth Hormone-Insulin-Like Growth Factor Axis, Thyroid Axis, Prolactin, and Exercise.

    PubMed

    Hackney, Anthony C; Davis, Hope C; Lane, Amy R

    2016-01-01

    This chapter addresses what is known about the endocrine system components growth hormone (GH)-insulin-like growth factor (IGF) axis, thyroid axis, and prolactin relative to exercise and exercise training. Each one of these hormone axes contributes to the maintenance of homeostasis in the body through impact on a multitude of physiological systems. The homeostatic disruption of exercise causes differing responses in each hormone axis. GH levels increase with sufficient stimulation, and IGFs are released in response to GH from the anterior pituitary providing multiple roles including anabolic properties. Changes in the thyroid hormones T3 and T4 vary greatly with exercise, from increases/decreases to no change in levels across different exercise types, intensities and durations. These ambiguous findings could be due to numerous confounding factors (e.g. nutrition status) within the research. Prolactin increases proportionally to the intensity of the exercise. The magnitude may be augmented with extended durations; conflicting findings have been reported with resistance training. While the responses to exercise vary, it appears there may be overall adaptive and regenerative impacts on the body into recovery by these hormones through immune and tissue inflammatory responses/mediations. Nonetheless, well-designed exercise research studies are still needed on each of these hormones, especially thyroid hormones and prolactin.

  16. How does the pathophysiological context influence delivery of bone growth factors?☆

    PubMed Central

    Yu, Xiaohua; Suárez-González, Darilis; Khalil, Andrew S.; Murphy, William L.

    2014-01-01

    “Orthobiologics” represents an important category of therapeutics for the regeneration of bone defects caused by injuries or diseases, and bone growth factors are a particularly rapidly growing sub-category. Clinical application of bone growth factors has accelerated in the last two decades with the introduction of BMPs into clinical bone repair. Optimal use of growth factor-mediated treatments heavily relies on controlled delivery, which can substantially influence the local growth factor dose, release kinetics, and biological activity. The characteristics of the surrounding environment, or “context”, during delivery can dictate growth factor loading efficiency, release and biological activity. This review discusses the influence of the surrounding environment on therapeutic delivery of bone growth factors. We specifically focus on pathophysiological components, including soluble components and cells, and how they can actively influence the therapeutic delivery and perhaps efficacy of bone growth factors. PMID:25453269

  17. End stage renal disease serum contains a specific renal cell growth factor

    SciTech Connect

    Klotz, L.H.; Kulkarni, C.; Mills, G. )

    1991-01-01

    End stage renal disease (ESRD) kidneys display abnormal growth characterized by a continuum of cystic disease, adenoma and carcinoma. This study evaluates the hypothesis that serum of patients with ESRD contains increased amounts of a growth factor which specifically induces proliferation of renal cells. ESRD sera compared to sera from normal controls induced a two to three-fold increase in the proliferative rate of renal cell carcinoma cell lines and normal kidney explants compared to cell lines from other sites. The increased proliferative activity of ESRD sera on renal cells was paralleled by an increase in cytosolic free calcium. The growth factor activity was encoded by a polypeptide of between 15 and 30 kd. The activity of ESRD sera on renal cells was not mimicked or inhibited by epidermal growth factor, basic fibroblast growth factor and platelet derived growth factor indicating that the renal cell specific growth factor activity in ESRD is different from these factors.

  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. Mutual effects of growth hormone and growth factors on avian skeletal muscle satellite cells.

    PubMed

    Hodik, V; Mett, A; Halevy, O

    1997-10-01

    Chicken growth hormone (cGH) has been shown to affect chicken skeletal muscle satellite cell proliferation and differentiation in vitro. This study describes the interactions of cGH with basic fibroblast growth factor (bFGF) and insulin-like growth factor I (IGF-I). Both cGH and bFGF induced cGH receptor (cGH-R) gene expression as well as that of the avian FGF receptor, FREK, when added at low concentrations to satellite cells. bFGF caused a rapid induction of cGH-R mRNA. Combinations of low levels of bFGF and cGH caused a further increase in receptor mRNA expression levels, relative to that caused by each peptide alone, and their effect on DNA synthesis was synergistic. However, combinations of cGH and bFGF at high concentrations decreased cGH-R and FREK mRNA levels and DNA synthesis in a dose-dependent manner. These results imply that the mutual effects of bFGF and cGH on satellite cell proliferation are receptor-mediated and that each peptide regulates both receptors gene expression. IGF-I induced DNA synthesis in satellite cells but did not affect cGH-R gene expression at any of the concentrations tested. Coincubation of 3.5 ng/ml cGH and various concentrations of IGF-I did not significantly change DNA synthesis relative to the effect of cGH alone. However, combinations with high levels of cGH abolished it. Similar time-course (up to 6 hr) induction of DNA synthesis in serum-starved cells was observed in the presence of cGH or IGF-I, suggesting that cGH affects satellite cell proliferation in an IGF-I-independent manner.

  20. Regulation of intestinal epithelial cell growth by transforming growth factor type. beta

    SciTech Connect

    Barnard, J.A.; Beauchamp, R.D.; Coffey, R.J.; Moses, H.L. )

    1989-03-01

    A nontransformed rat jejunal crypt cell line (IEC-6) expresses transforming growth factor type {beta}1 (TGF-{beta}1) mRNA, secretes latent {sup 125}I-labeled TGF-{beta}1 to specific, high-affinity cell surface receptors. IEC-6 cell growth is markedly inhibited by TGF-{beta}1 and TGF-{beta}2 with half-maximal inhibition occurring between 0.1 and 1.0 ng of TGF-{beta}1 per ml. TGF-{beta}1-mediated growth inhibition is not associated with the appearance of biochemical markers of enterocyte differentiation such as alkaline phosphatase expression and sucrase activity. TGF-{beta}1 increases steady-state levels of its own mRNA expression within 8 hr of treatment of rapidly growing IEC-6 cells. In freshly isolated rat jejunal enterocytes that are sequentially eluted from the crypt villus axis, TGF-{beta}1 mRNA expression is most abundant in terminally differentiated villus tip cells and least abundant in the less differentiated, mitotically active crypt cells. The authors conclude that TGF-{beta}1 is an autoregulated growth inhibitor in IEC-6 cells that potentially functions in an autocrine manner. In the rat jejunal epithelium, TGF-{beta}1 expression is most prominently localized to the villus tip--i.e., the region of the crypt villus unit that is characterized by the terminally differentiated phenotype. These data suggest that TGF-{beta}1 may function in coordination of the rapid cell turnover typical for the intestinal ep