Citations
All
Search in:AllTitleAbstractAuthor name
Publications
(1K+)
Patents
Grants
Pathways
Clinical trials
Publication
Journal: Traffic
May/23/2006
Abstract
<em>Growth</em> <em>factors</em> must be secreted appropriately to co-ordinate cell proliferation, specification and movement during development and to control cell numbers and migrations in adult animals. Previous results showed that the secretion of the Caenorhabditis elegans <em>fibroblast</em> <em>growth</em> <em>factor</em> homologue, EGL-<em>17</em>, from vulval precursor cells in vivo involves the cytoplasmic adaptor protein Ce-DAB-1 and two lipoprotein receptors that bind Ce-DAB-1 and EGL-<em>17</em>. Here, we confirm the Ce-DAB-1 requirement for EGL-<em>17</em> secretion using mutant animals. In vitro, Ce-DAB-1 binds to clathrin and APT-4, the C. elegans homologue of the alpha-adaptin subunit of adaptor protein 2 (AP2), and weakly to the gamma-appendage domains of APT-1 (AP1gamma-adaptin) and APT-9 (GGA protein). In tissue-culture cells, Ce-DAB-1 localizes to various compartments, including AP2-containing vesicles near the cell surface and perinuclear vesicles that contain AP1. The latter also contain Rab8, but not Rab5 or Rab11, as well as proteins en route from the trans Golgi network (TGN) to the surface. In vivo, EGL-<em>17</em> secretion was inhibited by depletion of apt-1, apt-9 or ce-rab-8 and partially inhibited by RNAi of ce-rab-5, consistent with an important role for these proteins in the secretion of EGL-<em>17</em> in vivo. These results suggest that Ce-DAB-1 might co-ordinate the assembly of endocytic or secretory vesicles in vivo and may mediate EGL-<em>17</em> secretion directly, by recruiting clathrin to lipoprotein receptors at the TGN, or indirectly, by affecting lipoprotein receptor endocytosis and recycling.
Publication
Journal: Molecular and Cellular Endocrinology
January/9/1995
Abstract
Hepatocyte <em>growth</em> <em>factor</em> (HGF) is expressed in a variety of tissues and cell types under normal conditions and in response to various stimuli such as tissue injury. In the present study, we demonstrate that the transcription of the HGF gene is stimulated by estrogen in mouse ovary. A single injection of <em>17</em> beta-estradiol results in a dramatic and transient elevation of the levels of mouse HGF mRNA. Sequence analysis has found that two putative estrogen responsive elements (ERE) reside at -872 in the 5'-flanking region and at +511 in the first intron, respectively, of the mouse HGF gene. To test whether these ERE elements are responsible for estrogen induction of HGF gene expression, chimeric plasmids containing variable regions of the 5'-flanking sequence of HGF gene and the coding region for chloramphenicol acetyltransferase (CAT) gene were transiently transfected into both human endometrial carcinoma RL 95-2 cells and mouse <em>fibroblast</em> NIH 3T3 cells to assess hormone responsiveness. Transfection results indicate that the ERE elements of the mouse HGF gene can confer estrogen action to either homologous or heterologous promoters. Nuclear protein extracts either from RL95-2 cells transfected with the estrogen receptor expression vector or from mouse liver bound in vitro to ERE elements specifically, as shown by band shift assay. Therefore, our results demonstrate that the HGF gene is transcriptionally regulated by estrogen in mouse ovary; and such regulation is mediated via a direct interaction of the estrogen receptor complex with cis-acting ERE elements identified in the mouse HGF gene.
Publication
Journal: Journal of Biological Chemistry
May/18/2003
Abstract
The neural cell adhesion molecule (NCAM) plays a key role in morphogenesis of the nervous system and in remodeling of neuronal connections accompanying regenerative and cognitive processes. Recently, a new synthetic ligand of NCAM, the C3-peptide, which binds to the NCAM IgI module, has been identified by means of combinatorial chemistry (Rønn, L. C. B, Olsen, M., Ostergaard, S., Kiselyov, V., Berezin, V., Mortensen, M. T., Lerche, M. H., Jensen, P. H., Soroka, V., Saffell, J. L., Doherty, P., Poulsen, F. M., Bock, E., Holm, A., and Saffells, J. L. (1999) Nat. Biotechnol. <em>17</em>, 1000-1005). In vitro, the dendrimeric form of C3, termed C3d, disrupts NCAM-mediated cell adhesion, induces neurite out<em>growth</em>, and triggers intracellular signaling cascades similar to those activated by homophilic NCAM binding. The peptide may therefore be expected to regulate regeneration and synaptic plasticity. Here we demonstrate that in primary cultures of hippocampal neurons: 1) C3d induces a sustained neuritogenic response, the neuritogenic activity of the compound being dependent on the dose, starting time, and duration of peptide application; 2) the peptide triggers the neuritogenic response by forming an adhesive substratum necessary for NCAM-mediated neurite formation and elongation; 3) C3d promotes synapse formation; and 4) C3d modulates the presynaptic function, causing a transient increase of the function at low (2 and 5 microm) doses and a reduction when applied at a higher concentration (10 microm). The effect of the peptide is dependent on the activation of the <em>fibroblast</em> <em>growth</em> <em>factor</em> receptor. We suggest that C3d may constitute a useful lead for the development of compounds for treatment of various neurodegenerative disorders.
Publication
Journal: European Journal of Cancer
October/31/2004
Abstract
The competitive inhibitory effects of NK4 (a specific hepatocyte <em>growth</em> <em>factor</em> (HGF)-antagonist) on the interaction between HGF and the c-Met/HGF receptor has been shown in HGF-mediated invasion of some distinct types of human cancer cells. Furthermore, NK4 has inhibitory effects on the angiogenic pathways driven by basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) and vascular endothelial <em>growth</em> <em>factor</em> (VEGF), as well as by HGF. In this study, to evaluate the therapeutic efficacy of adenoviral-mediated NK4 gene treatment, we employed animal models of peritoneal metastasis using two gastric cancer cell lines, the strongly c-Met expressing MKN45 cell line and the weakly c-Met-expressing cell line, TMK1. In both models, the total number and weight of peritoneal tumours per mouse and ascites treated early with AxCANK4 (administered 3 times 2, 7 and 12 days after the tumour inoculation) were significantly reduced compared with those treated with phosphate-buffered solution (PBS) and AxCALacZ (P < 0.05). In <em>Factor</em>-VIII-related-antigen-stained sections from peritoneal metastatic tumours, the inhibition of intratumour vessels was observed in tissues from tumours of MKN45 and TMK1 treated with AxCANK4. We also compared the therapeutic effect of early AxCANK4 treatment with that of late treatment (at 7, 12 and <em>17</em> days). Peritoneal metastases and ascites treated late with AxCANK4 showed less of an improvement than those treated early with AxCANK4 in both models. In addition, the inhibitory effect of cisplatin (CDDP) on peritoneal metastasis was significantly enhanced by AxCANK4, suggesting that the combination of intraperitoneal (i.p.) chemotherapy with NK4 gene therapy might be effective, even in cases of advanced peritoneal metastasis from gastric cancer. To conclude, these results show clearly that NK4 gene therapy inhibits peritoneal metastases from gastric cancer, regardless of the level of c-Met/HGF receptor expression in the tumour cells, and especially in the early stages of peritoneal metastasis.
Publication
Journal: Endocrinology
October/23/1994
Abstract
We have previously reported the presence of proteolytic activity in conditioned medium from human <em>fibroblast</em> cultures that cleaves insulin-like <em>growth</em> <em>factor</em>-binding protein-5 (IGFBP-5) into non-IGF-I-binding fragments. Coincubation of IGF-I or IGF-II and IGFBP-5 with <em>fibroblast</em> cultures decreased proteolysis. The protease was purified by heparin-Sepharose affinity chromatography. The purified protease cleaved IGFBP-5 into 22-, 20-, and <em>17</em>-kilodalton non-IGF-I-binding fragments. Protease inhibitor profiles obtained using partially purified enzyme showed that it was a calcium-dependent serine protease. After chelation with EDTA, the activity could only be partially restored with zinc, indicating that it was probably not a metalloprotease. The protease was specific for IGFBP-5 and did not cleave pure IGFBP-1, -2, -3, or -4. IGF-I and IGF-II caused minimal inhibition of proteolysis in vitro. This suggests that the IGF-I-induced increase in IGFBP-5 in <em>fibroblast</em> medium is only partially due to direct protease inhibition. Heparin, antithrombin-III (AT-III), and heparin co<em>factor</em>-II had inhibitory activity, and heparin potentiated the activity of AT-III. Synthetic peptides, that contained the active sites of AT-III and alpha 1-antichymotrypsin, were also inhibitory. Peptides containing sequences found in two basic regions of IGFBP-5 were tested, and one had inhibitory activity. In summary, <em>fibroblasts</em> secrete a serine protease that cleaves IGFBP-5 and is specific for this form of IGFBP. The protease has properties that are similar to kallikreins, a family of serine proteases that is known to cleave epidermal and nerve <em>growth</em> <em>factor</em>-binding proteins.
Publication
Journal: Hippocampus
October/3/2004
Abstract
Progenitor cells that endure in different regions of the CNS after the initial neurogenesis can be expanded in culture and used as a source of donor tissue for grafting in neurodegenerative diseases. However, the proliferation and differentiation characteristics of residual neural progenitor cells from distinct regions of the CNS are mostly unknown. This study elucidated the characteristics of progenitor cells that endure in the CA3 region of the hippocampus after neurogenesis, by in vitro analyses of cells that are responsive to epidermal <em>growth</em> <em>factor</em> (EGF) or <em>fibroblast</em> <em>growth</em> <em>factor</em>-2 (FGF-2) in the embryonic day 19 (E19) rat hippocampus. Isolated cells from the E19 CA3 region formed neurospheres in the presence of either EGF or FGF-2, but the yield of neurospheres was greater with FGF-2 exposure, Differentiation cultures revealed a greater yield of neurons from FGF-2 neurospheres (60%) than from EGF neurospheres (35%). Exposure to brain-derived neurotrophic <em>factor</em> (BDNF) enhanced the yield of neurons from EGF neurospheres but had no consequence on FGF-2 neurospheres. A large number of neurons from EGF/FGF-2 neurospheres demonstrated clearly palpable morphological features of CA3 pyramidal neurons and lacked gamma-aminobutyric acid (GABA) expression. However, a fraction of neurons (<em>17</em>-20%) from EGF/FGF-2 neurospheres expressed GABA, and exposure to BDNF increased the number of GABAergic neurons (30%) from EGF neurospheres. Neurons from EGF/FGF-2 neurospheres also contained smaller populations of calbindin- and calretinin-positive interneuron-like cells. Thus, progenitor cells responsive to FGF-2 are prevalent in the CA3 region of the E19 rat hippocampus and give rise to a greater number of neurons than progenitor cells responsive to EGF. However, both FGF-2- and EGF-responsive progenitor cells from E19 CA3 region are capable of giving rise to CA3 field-specific phenotypic neurons. These results imply that progenitor cells that persist in the hippocampus after neurogenesis remain regionally restricted and hence retain their ability to give rise to region-specific phenotypic neurons even after isolation and expansion in vitro.
Publication
Journal: Journal of neurobiology
September/28/1994
Abstract
One function of Alzheimer amyloid protein precursor (APP) is the regulation of <em>growth</em> and differentiation in several types of cells, including <em>fibroblasts</em>, PC12 cells, and neurons. This activity is represented by a small stretch of amino acids in the center of the molecule around RERMS. The APP <em>17</em>-mer peptide containing the RERMS domain supported survival and neurite extension of rat cortical neurons in a dose-dependent and sequence-specific manner. The APP fragment synthesized in Escherichia coli supported the survival and neurite extension of rat cortical neurons, whereas the mutant APP fragment lacking the 30 amino acids around the RERMS domain had drastically reduced activity to support the survival and neurite extension. The current study established APP as a neuron survival <em>factor</em> and determined that the sequence around RERMS is important for this function.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
May/13/1980
Abstract
Nerve <em>growth</em> <em>factor</em> was measured in cultured human skin <em>fibroblasts</em> from controls and from patients with familial dysautonomia and dystonia musculoram deformans. Cells from these sources grown over a range of cell densities contained similar levels of beta-nerve <em>growth</em> <em>factor</em> as measured by radioimmunoassay. Results of bioassay demonstrated that the nerve <em>growth</em> <em>factor</em> from dysautonomic cells was only approximately 10% as active per ng of immunoreactive protein as that from control and dystonic cells. Treatment of <em>fibroblasts</em> with the beta-adrenergic agonist isoproterenol resulted in a <em>17</em>- to <em>17</em>0-fold rise in the cyclic AMP content of both control and dysautonomic cells in 10 min. The content of immunoreactive beta-nerve <em>growth</em> <em>factor</em> in control <em>fibroblasts</em> increased 50--300% after 3--4 hr of exposure to isoproterenol. At no time, throughout a 7.5 hr period, was there a change in the amount of immunoreactive beta-nerve <em>growth</em> <em>factor</em> in the dysautonomic cells. These studies suggest that the molecular basis of the genetic defect in familial dysautonomia may lie in processing of the precursor or in the structure of the biologically active beta subunit of nerve <em>growth</em> <em>factor</em>.
Publication
Journal: Journal of Neurosurgery
May/20/2010
Abstract
OBJECTIVE
Fibroblast growth factor receptors (FGFRs)-1, -2, and -3 are expressed in the developing brain and may participate in CNS neoplasia. Fibroblast growth receptor-3 has not been demonstrated in the human CNS or its tumors. Nonetheless, it has been implicated in the pathogenesis of several other forms of neoplasia.
METHODS
Twenty-four human meningiomas were evaluated using Western blot analysis for expression of FGFR3, its ligand acidic FGF, and concomitant phosphorylation/activation of p44/42 mitogen-activated protein kinase (MAPK), Akt, and STAT3. Mutations in exons 7 and 10 of the FGFR3 gene were analyzed by polymerase chain reaction in 10 meningiomas. Primary meningioma cells cultured from 10 human meningiomas were also treated with acidic FGF and evaluated for cell proliferation or activation/phosphorylation of p44/42 MAPK, Akt, and STAT3.
RESULTS
Immunoblotting demonstrated the presence of FGFR3 in 12 (71%) of 17 primarily fibroblastic and transitional WHO Grade I meningiomas. The FGFR3 was detected in 4 (80%) of 5 WHO Grade II, and 2 of 2 Grade III tumors. Acidic FGF was detected in 3 (18%) of 17 Grade I, 1 (20%) of 5 Grade II, and 1 (50%) of 2 Grade III meningiomas. In WHO Grade I meningiomas, 3 of 6 tumors with no detectable FGFR3 had no detectable p-STAT3. In WHO Grades II and III meningiomas, FGFR3 expression was associated with p-STAT3, p-Akt, and p-p44/42 MAPK expression. No mutations were demonstrated in exons 7 or 10 by polymerase chain reaction in any meningioma. Treatment with acidic FGF, a ligand for FGFR3, stimulated meningioma cell proliferation and activation of Akt and STAT3 in primary meningioma cell cultures.
CONCLUSIONS
These findings suggest that FGFR3 and acidic FGF are expressed in adult human leptomeninges as well as WHO Grades I and II meningiomas. Fibroblast growth factor receptor-3 activation stimulates meningioma cell proliferation by activation of the phosphoinositide 3 kinase-Akt-PRAS40-mTOR and STAT3 pathways.
Publication
Journal: Journal of Investigative Dermatology
April/14/1991
Abstract
Basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) is a mitogen for normal human melanocytes and keratinocytes in culture. Experiments in vitro suggest that keratinocytes supply bFGF to melanocytes through a paracrine mechanism and that the aberrant expression of bFGF in melanomas confers <em>growth</em> independence from bFGF-producing cells. To determine whether bFGF is expressed in vivo, we examined a series of benign and malignant melanocytic lesions in situ using bFGF riboprobes on tissue sections, and correlated bFGF expression with histologic phenotype. Seventeen melanocytic neoplasms were studied, including four common acquired nevi, four dysplastic nevi, four primary malignant melanomas, and five metastatic melanomas. Nevic cells in benign intradermal nevi showed low signal intensity (1+), whereas compound and dysplastic nevi showed 2+ to 3+ expression in the junctional nevic cell population and 1+ expression in the dermal nevic cell population. Melanocytes in primary melanomas had intermediate (2+) and those in metastatic melanomas had low (1+) levels of bFGF gene transcripts. <em>Fibroblasts</em> expressed high levels (3+) and epidermal and adnexal keratinocytes moderate (2+) levels of bFGF in all cases studied. Basic FGF expression in endothelial cells, known to produce and respond to this <em>growth</em> <em>factor</em> in vitro, was lower than that in the <em>fibroblast</em> and keratinocyte cell population and, in 10 of <em>17</em> cases, no bFGF mRNA was detectable. This study shows that bFGF is expressed in nevomelanocytes in vivo in all melanocytic lesions studied and thus cannot be used as a marker for transformation. The presence of bFGF gene transcripts in the various dermal cell types and in keratinocytes suggests that it may act as an autocrine and paracrine <em>growth</em> <em>factor</em> in regulating cellular proliferation in the skin.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
November/26/2007
Abstract
Aldosterone elicits physiological responses through the modulation of gene expression and by stimulating signaling processes. Here we investigated the activation pathway of protein kinase D1 (PKD1) by aldosterone in the murine M1 renal cortical collecting duct cell line. Aldosterone stimulated a rapid increase in PKD1 activity peaking at 2-5 min and at 30 min after treatment that was insensitive to inhibitors of transcription or translation. PKD1 was not activated by aldosterone in MR null NIH-3T3 <em>fibroblasts</em> or M1-CCD cells propagated without dexamethasone, which did not express MR. PKD1 activation was sensitive to the MR antagonists spironolactone and RU28318 but not to the glucocorticoid receptor antagonist RU486. Aldosterone activation of PKD1 was inhibited by the epidermal <em>growth</em> <em>factor</em> (EGFR) antagonist tyrphostin AG1478 and by the c-Src inhibitor PP2. Western blotting revealed EGFR phosphorylation following aldosterone treatment at the c-Src tyrosine kinase-specific residue Tyr845. The activation of c-Src was dependent on its interaction with HSP84, since HSP84 antagonist <em>17</em>-AAG inhibited both the phosphorylation of EGFR in response to aldosterone by c-Src and also the subsequent activation of PKD1.
Publication
Journal: Journal of Cellular Physiology
January/11/1989
Abstract
Basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) has been demonstrated to exert an angiogenic activity in vivo. Here, the ability of bFGF to stimulate plasminogen activator (PA) production in bovine capillary endothelial cells was used as an assay for the presence of bFGF-like molecules in the extracts of the human endometrial adenocarcinoma AN3CA, HEC-1-A, and HEC-1-B cell lines. The identity of the PA-stimulating activity with bFGF was confirmed by its high affinity for heparin and by its cross-reactivity with antibodies to human placental bFGF. Western blot analysis and immunoprecipitation experiments showed that, in the extracts of the three cell lines, these antibodies recognize a protein with an apparent molecular weight of approximately <em>17</em>,000 daltons. <em>17</em> beta-Estradiol stimulates the synthesis of this bFGF-like molecule in all the endometrial cell lines tested. This stimulation can be abolished by treating the cells with progesterone. These data demonstrate the capacity of sex hormones to regulate bFGF synthesis in tumor endometrial cells, and they suggest that bFGF may play a role in the vascularization of the endometrial adenocarcinoma as well as of the normal endometrium.
Authors
Publication
Journal: Journal of Neurochemistry
November/19/2002
Abstract
In this study, the internalization mechanism of basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) at the blood-brain barrier (BBB) was investigated using a conditionally immortalized mouse brain capillary endothelial cell line (TM-BBB4 cells) as an in vitro model of the BBB and the corresponding receptor was identified using immunohistochemical analysis. The heparin-resistant binding of [125I]bFGF to TM-BBB4 cells was found to be time-, temperature-, osmolarity- and concentration-dependent. Kinetic analysis of the cell-surface binding of [125I]bFGF to TM-BBB4 cells revealed saturable binding with a half-saturation constant of 76 +/- 24 nm and a maximal binding capacity of 183 +/- <em>17</em> pmol/mg protein. The heparin-resistant binding of [125I]bFGF to TM-BBB4 was significantly inhibited by a cationic polypeptide poly-L-lysine (300 micro m), and compounds which contain a sulfate moiety, e.g. heparin and chondroitin sulfate-B (each 10 micro g/mL). Moreover, the heparin-resistant binding of [125I]bFGF in TM-BBB4 cells was significantly reduced by 50% following treatment with sodium chlorate, suggesting the loss of perlecan (a core protein of heparan sulfate proteoglycan, HSPG) from the extracellular matrix of the cells. This type of binding is consistent with the involvement HSPG-mediated endocytosis. RT-PCR analysis revealed that HSPG mRNA and FGFR1 and FGFR2 (tyrosine-kinase receptors for bFGF) mRNA are expressed in TM-BBB4 cells. Moreover, immunohistochemical analysis demonstrated that perlecan is expressed on the abluminal membrane of the mouse brain capillary. These results suggest that bFGF is internalized via HSPG, which is expressed on the abluminal membrane of the BBB. HSPG at the BBB may play a role in maintaining the BBB function due to acceptance of the bFGF secreted from astrocytes.
Publication
Journal: DNA and Cell Biology
January/28/2014
Abstract
The incidence of premature ovarian failure (POF), a condition causing amenorrhea and hypergonadotropic hypoestrogenism in women before the age of 40, has been increasing in recent years. As an irreversible pathological change, improved treatment strategies for this disease are urgently needed. In this study, a type of microRNA (miR-<em>17</em>-3p) was used to guide the differentiation of human-induced pluripotent stem (iPS) cells into hormone-sensitive ovarian epithelial (OSE)-like cells in vitro. To prevent their morphological transformation into <em>fibroblast</em>-like cells, MiR-<em>17</em>-3p, a microRNA that suppresses vimentin expression, was transfected into human iPS cells. Subsequently, these cells were successfully induced into OSE-like cells in vitro after treatment with estrogen and cell <em>growth</em> <em>factors</em>. Compared with controls, iPS cells transfected with miR-<em>17</em>-3p expressed higher levels of epithelial markers (cytokeratin 7, AE1, AE3, and E-cadherin) and estrogen receptors (ERα and ERβ) while levels of mesenchymal markers (fibronectin, vimentin, and N-cadherin) lowered after the induction. The human iPS cell-derived OSE-like cells were then injected into cyclophosphamide-induced POF model mice to determine their potential benefit as grafts to repair ovarian tissues. The OSE-like cells survived within POF mouse ovaries for at least 14 days in vivo. Compared with the negative controls, expressions of cytokeratin 7 and ERβ proteins were elevated while fibronectin and vimentin levels in ovarian tissues were downregulated in the OSE-like cell transplantation group. Moreover, the ovarian weight and plasma E2 level increased over time in the transplantation with OSE-like cells, compared with control groups. Hence, we can draw the conclusion that iPS cells can be induced to differentiate into OSE-like cells in vitro.
Publication
Journal: European journal of biochemistry
March/12/1995
Abstract
Aldose reductase (alditol:NAD(P)+ 1-oxidoreductase), an enzyme implicated in the pathogenesis of various diabetic complications, catalyzes the reduction of a variety of aldehydes. From a mouse kidney library, we isolated aldose reductase cDNA that encodes a 316-amino-acid protein with approximately 97% identity to rat lens aldose reductase, approximately 69% identity to the mouse vas deferens protein and also approximately 69% identity to mouse <em>fibroblast</em> <em>growth</em>-<em>factor</em>-1-regulated protein. RNA-blot analysis demonstrated abundant expression of the enzyme transcript in the testis, skeletal muscle and kidney. However, a very low level of the transcript was detected in the sciatic nerve and lens, where abundant expression and involvement of the enzyme in diabetic complications were documented in other animals species. The isolated cDNA was expressed in Escherichia coli and the recombinant protein was purified to homogeneity by affinity chromatography and chromatofocusing. The expressed enzyme demonstrated reductase activity for various aldo sugars but not for the steroids. The enzyme reaction with DL-glyceraldehyde was, however, competitively inhibited by progesterone or <em>17</em> alpha-hydroxyprogesterone. The results not only indicate a unique tissue distribution and enzyme attribute of mouse aldose reductase, but also the presence of a closely related subgroup within the aldo-oxidoreductase superfamily in mouse tissues.
Publication
Journal: Molecular Vision
December/7/2015
Abstract
OBJECTIVE
The aim of this study was to assess the roles of plasma cytokines in diabetic retinopathy (DR) and their relationship with the severity of DR.
METHODS
This study included 59 diabetic patients and 19 non-diabetic controls. The plasma concentrations of endothelial <em>growth</em> <em>factor</em> (EGF), eotaxin, <em>fibroblast</em> <em>growth</em> <em>factor</em> 2 (FGF-2), Flt-3 ligand (Flt-3L), fractalkine, granulocyte colony-stimulating <em>factor</em> (G-CSF), granulocyte-macrophage colony-stimulating <em>factor</em> (GM-CSF), <em>growth</em>-related oncogene (GRO), interferon (IFN)-α2, IFN-γ, interleukin (IL)-1α, IL-1β, IL-1Ra, IL-2, IL-3, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-10, IL-12 (p40), IL-12 (p70), IL-13, IL-15, IL-<em>17</em>, IFN-inducible protein-10 (IP-10), monocyte chemoattractant protein (MCP)-1, MCP-3, macrophage-derived cytokine (MDC), macrophage inflammatory protein (MIP)-1α, MIP-1β, sCD40L, sIL-2Rα, transforming <em>growth</em> <em>factor</em> (TGF)-α, tumor necrosis <em>factor</em> (TNF)- α, TNF-β, and VEGF were measured with Luminex multiplex bead immunoassay. The levels of these cytokines were investigated according to the DR stage.
RESULTS
The plasma level of ten cytokines-MCP-1, IL-6, IL-7, IL-9, IL-13, IL-15, IL-<em>17</em>, sCD40L, sIL-2Rα and TNF-β-increased significantly in the diabetic group compared to the controls. The Flt-3L, IL-1Ra, IL-3, IL-5, and IL-12 (p40) levels were lower in the diabetic group than in the control group. The TNF-α plasma level was significantly elevated in patients with proliferative diabetic retinopathy (PDR) compared with the levels in patients with non-proliferative diabetic retinopathy (NPDR) and patients with no apparent diabetic retinopathy (NDR).
CONCLUSIONS
TNF-α might be involved in the progression of DR, especially in the pathogenesis of PDR. TNF-α is a potential cytokine for the prognosis of DR and might act as a therapeutic target in DR.
Publication
Journal: International Journal of Radiation Oncology Biology Physics
July/24/2008
Abstract
OBJECTIVE
In addition to invasive tumor cells, endothelial cells (ECs) of the tumor vasculature are an important target for anticancer radiotherapy. The purpose of the present work is to investigate how <em>17</em>-N-allilamino-<em>17</em>-demethoxygeldanamycin (<em>17</em>AAG), known as an anticancer drug inhibiting heat shock protein 90 (Hsp90), modifies radiation responses of human vascular ECs.
METHODS
The ECs cultured from human umbilical veins were exposed to gamma-irradiation, whereas some EC samples were pretreated with growth factors and/or <em>17</em>AAG. Postirradiation cell death/survival and morphogenesis were assessed by means of terminal deoxynucleotidyl transferase biotin-deoxyuridine triphosphate nick end labeling or annexin V staining and clonogenic and tube-formation assays. The <em>17</em>AAG-affected expression and phosphorylation of radioresistance-related proteins were probed by means of immunoblotting. Dominant negative or constitutively activated Akt was transiently expressed in ECs to manipulate Akt activity.
RESULTS
It was found that nanomolar concentrations of <em>17</em>AAG sensitize ECs to relatively low doses (2-6 Gy) of gamma-irradiation and abolish the radioprotective effects of vascular endothelial growth factor and basic fibroblast growth factor. The drug-induced radiosensitization of ECs seems to be caused by prevention of Hsp90-dependent phosphorylation (activation) of Akt that results in blocking the radioprotective phosphatidylinositol 3-kinase/Akt pathway.
CONCLUSIONS
Clinically achievable concentrations of <em>17</em>AAG can decrease the radioresistance intrinsic to vascular ECs and minimize the radioprotection conferred upon them by tumor-derived growth factors. These findings characterize <em>17</em>AAG as a promising radiosensitizer for the tumor vasculature.
Publication
Journal: Journal of Vascular Surgery
November/12/2008
Abstract
OBJECTIVE
The importance of wound cytokine function in chronic venous leg ulcers remains poorly understood. This study evaluated the relationship between local and systemic concentrations of wound cytokines and wound healing in patients with chronic venous ulceration.
METHODS
This prospective observational study was set in a community- and hospital-based leg ulcer clinic. Consecutive patients with chronic leg ulceration and ankle-brachial pressure index >0.85 were prospectively investigated. All patients were treated with multilayer compression bandaging. Wound fluid and venous blood samples were collected at recruitment and 5 weeks later. In the wound fluid and venous blood, cytokines and factors reflecting the processes of inflammation (interleukin 1beta, tumor necrosis factor-alpha), proteolysis (matrix metalloproteinases-2 and -9), angiogenesis (basic fibroblast growth factor [bFGF], vascular endothelial growth factor), and fibrosis (transforming growth factor-beta(1) [TGFbeta(1)]) were measured. Ulcer healing was assessed using digital planimetry at both assessments.
RESULTS
The study comprised 80 patients (43 men, 37 women). Median (range) ulcer size reduced from 4.4 (0.1-142.4) cm(2) to 2.2 (0-135.5) cm(2) after 5 weeks (P < .001; Wilcoxon signed rank), although 17 of 80 ulcers increased in size. The volume of wound fluid collected strongly correlated with ulcer size (Spearman rank = 0.801, P < .01). Initial wound fluid concentrations of bFGF correlated with ulcer size (Pearson coefficient = 0.641, P < .01), and changes in wound fluid TGFbeta(1) concentrations inversely correlated with changes in ulcer size (Spearman rank = -0.645, P = .032). There were no significant correlations between changes in other factors and ulcer healing. Wound fluid and serum cytokine concentrations correlated poorly.
CONCLUSIONS
Wound fluid collection volume correlates with ulcer size. Ulcer healing correlated with increased concentrations of TGFbeta(1), possibly reflecting increased fibrogenesis in the proliferating wound. Aside from this, there was a large variation in wound and serum cytokine levels that largely limits their usefulness as markers of healing.
Publication
Journal: Wound Repair and Regeneration
June/29/2015
Abstract
Peritoneal adhesions are fibrous tissues formed after surgery. Both cytokines and transforming <em>growth</em> <em>factors</em> (TGFs) are involved in this process. The objective of this study was to investigate the cross talk between these entities. Peritoneal drainage fluid after surgery from patients and rodent models was examined by enzyme-linked immunosorbent assay and fluorescence-activated cell sorter. Data showed that the concentrations of interferon (IFN)-γ and interleukin (IL)-<em>17</em> reached their peaks 6-12 hours after surgery, whereas TGF-β1 concentrations showed two postoperative peak time points at 2 and 72-96 hours. By neutralizing IFN-γ, IL-<em>17</em> 6-12 hours, and TGF-β1 72-96 hours after surgery, the degree of adhesion reduced significantly. However, neutralizing TGF-β1 2 hours after surgery did not affect adhesion formation. Furthermore, in vitro studies showed that compared with the <em>fibroblasts</em> that were directly stimulated with TGF-β1, the prestimulation of IL-<em>17</em> promoted plasminogen activator inhibitor-1 production while inhibiting tissue-type plasminogen activator production. Moreover, additional stimulation with IFN-γ enhanced this effect. Together, these data indicate that IL-<em>17</em> may promote adhesion formation by increasing the reaction of <em>fibroblasts</em> against TGF-β1. Blocking IL-<em>17</em> might have a therapeutic potential in preventing adhesion formation after surgery.
Publication
Journal: Journal of Investigative Dermatology
May/1/2003
Abstract
Reorganization of skin during wound healing, inflammatory disorders, or cancer <em>growth</em> is the result of expression changes of multiple genes associated with tissue morphogenesis. We wanted to identify proteins involved in skin remodeling and select those that may be targeted for agonistic or antagonist therapeutic approaches in various disease processes. Full-thickness human skin was grafted to severe combined immunodeficient mice and injected intradermally with 38 different adenoviral vectors inserted with 37 different genes coding for <em>growth</em> <em>factors</em>, cytokines, proteolytic enzymes and their inhibitors, adhesion receptors, oncogenes, and tumor suppressor genes. Responses were characterized for infiltration of inflammatory cells, vascular density, matrix formation, <em>fibroblast</em>-like cell proliferation, and epidermal hyperplasia. Of the <em>17</em> <em>growth</em> <em>factor</em> vectors, 16 induced histological changes in human skin. Members of the VEGF and angiopoietin families induced neovascularization. PDGFs and TGF-betas stimulated connective tissue formation, and the chemokines IL-8 and MCP-1 attracted inflammatory neutrophils and monocytes, respectively. The serine protease uPA induced a vascular response similar to that of VEGF. Vectors with adhesion receptors, oncogenes and tumor suppressor genes had, with few exceptions, little effects on skin architecture. The overall results suggest that adenoviral vectors can effectively remodel the architecture of human skin for studies in morphogenesis, inflammatory skin disorders, wound healing, and cancer development.
Publication
Journal: American Journal of Clinical Nutrition
October/31/2019
Abstract
<AbstractText>Epidemiological studies have shown that increased circulating branched-chain amino acids (BCAAs) are associated with insulin resistance and type 2 diabetes (T2D). This may result from altered energy metabolism or dietary habits.</AbstractText><AbstractText>We hypothesized that a lower intake of BCAAs improves tissue-specific insulin sensitivity.</AbstractText><AbstractText>This randomized, placebo-controlled, double-blinded, crossover trial examined well-controlled T2D patients receiving isocaloric diets (protein: 1 g/kg body weight) for 4 wk. Protein requirements were covered by commercially available food supplemented ≤60% by an AA mixture either containing all AAs or lacking BCAAs. The dietary intervention ensured sufficient BCAA supply above the recommended minimum daily intake. The patients underwent the mixed meal tolerance test (MMT), hyperinsulinemic-euglycemic clamps (HECs), and skeletal muscle and white adipose tissue biopsies to assess insulin signaling.</AbstractText><AbstractText>After the BCAA- diet, BCAAs were reduced by <em>17</em>% during fasting (P < 0.001), by 13% during HEC (P < 0.01), and by 62% during the MMT (P < 0.001). Under clamp conditions, whole-body and hepatic insulin sensitivity did not differ between diets. After the BCAA- diet, however, the oral glucose sensitivity index was 24% (P < 0.01) and circulating <em>fibroblast</em>-<em>growth</em> <em>factor</em> 21 was 21% higher (P < 0.05), whereas meal-derived insulin secretion was 28% lower (P < 0.05). Adipose tissue expression of the mechanistic target of rapamycin was 13% lower, whereas the mitochondrial respiratory control ratio was 1.7-fold higher (both P < 0.05). The fecal microbiome was enriched in Bacteroidetes but depleted of Firmicutes.</AbstractText><AbstractText>Short-term dietary reduction of BCAAs decreases postprandial insulin secretion and improves white adipose tissue metabolism and gut microbiome composition. Longer-term studies will be needed to evaluate the safety and metabolic efficacy in diabetes patients.This trial was registered at clinicaltrials.gov as NCT03261362.</AbstractText>
Publication
Journal: Small
October/7/2008
Abstract
The tumor-inhibitory effect of C60(OH)x was tested on the murine H22 hepatocarcinoma model. Doses of 0.2 and 1.0 mg kg(-1) body weight both showed significant antitumor activity with tumor inhibition rates of 31.9 and 38.4%, respectively, when mice were treated for <em>17</em> consecutive days. The damnification of liver was prominently reduced. Furthermore, histological examination indicated that an envelope of <em>fibroblasts</em> and lymphocytes was formed surrounding tumor tissues in the C60(OH)x-treated group, which inhibited the infiltration of tumor to the neighboring normal skeleton muscle tissues. To understand the antitumor mechanism, the immunomodulatory activity of C60(OH)x was investigated. The results indicate that C60(OH)x enhances the phagocytosis of peritoneal macrophages and elevates the activity of arginase and acid phosphatase in vivo. The tumor necrosis <em>factor</em> alpha production of C60(OH)x-treated macrophages also increases in vitro. These results suggest that C60(OH)x can enhance the innate immunity of tumor-bearing mice, and therefore inhibits <em>growth</em> of the tumor.
Publication
Journal: Mechanisms of Development
March/7/2001
Abstract
Members of the <em>fibroblast</em> <em>growth</em> <em>factor</em> (Fgf) family are important signaling molecules in several inductive and patterning processes, and act as brain organizer-derived signals during formation of the early vertebrate nervous system. We isolated a new member of the Fgf8/<em>17</em>/18 subgroup of Fgfs from the zebrafish, and studied its expression and function during somitogenesis, optic stalk and midbrain-hindbrain boundary (MHB) development. In spite of a slightly higher aminoacid similarity to Fgf8, expression analysis and mapping to a chromosome stretch that is syntenic with mammalian chromosomes shows that this gene is orthologous to mammalian Fgf<em>17</em>. These data provide a further example of conserved chromosomal organization between zebrafish and mammalian genomes. Using an mRNA injection assay, we show that fgf<em>17</em> can act similar to fgf8 during gastrulation, when fgf<em>17</em> is not normally expressed. Direct comparison of the expression patterns of fgf<em>17</em> and fgf8 suggest however a possible cooperation of these Fgfs at later stages in several tissues requiring Fgf signaling. Analysis of zebrafish MHB mutants demonstrates a gene-dosage dependent requirement of fgf<em>17</em> expression for the no isthmus// pax2.1 gene, showing that no isthmus/pax2.1 functions upstream of fgf<em>17</em> at the MHB in a haplo-insufficient manner, similar to what has been reported for mammalian pax2 mutants. In contrast, only maintenance of fgf<em>17</em> expression is disturbed at the MHB of acerebellar/fgf8 mutants. Consistent with a requirement for fgf8 function, implantation of FGF8-soaked beads induces fgf<em>17</em> expression, and expression is upregulated in aussicht mutants, which display upregulation of the Fgf8 signaling pathway. Taken together, our results argue that Fgf8 and Fgf<em>17</em> act as hierarchically organized signaling molecules during development of the MHB organizer and possibly other organizers in the developing nervous system.
Publication
Journal: Cornea
September/30/2010
Abstract
OBJECTIVE
To evaluate the efficacy of topically applied autologous plasma rich in growth factors (PRGF) as a treatment for persistent epithelial defects (PEDs) of the cornea.
METHODS
A series of prospective noncomparative cases.
METHODS
Twenty eyes from 18 patients with PED with various underlying etiopathologies: neurogenic, iatrogenic, associated with burning or secondary to severe dry eye. Patients were treated with a PRGF eyedrop solution. Serial photographs of the cornea were taken until epithelialization was complete. We had previously characterized the levels of a panel of growth factors (platelet-derived growth factor, epithelial growth factor, vascular endothelial growth factor, hepatocyte growth factor, fibroblast growth factor, and nerve growth factor) in the PRGF of 11 of these patients. The following variables were additionally recorded: (1) duration of PED before treatment, (2) previous treatments, (3) time for complete epithelialization, and (4) treatments required concomitantly with PRGF.
RESULTS
Epithelial defects healed in 17 of 20 cases (85%), with a mean therapeutic time of 10.9 weeks (range 2-39 weeks). Mean progression time before treatment was 26.7 weeks (range 2-104 weeks). Growth factor concentrations were platelet-derived growth factor 12645.9 +/- 1690.0 pg/mL, epithelial growth factor 468.9 +/- 97.6 pg/mL, vascular endothelial growth factor 204.5 +/- 119.4 pg/mL, hepatocyte growth factor 149.5 +/- 173.5 pg/mL, fibroblast growth factor 82.6 +/- 95.9 pg/mL, and nerve growth factor 37.7 +/- 18.6 pg/mL.
CONCLUSIONS
PRGF, when applied as eyedrops, is a highly effective therapeutic agent for the treatment of a broad etiopathological spectrum of corneal PEDs.
load more...