1
|
Song M, Finley SD. Mechanistic characterization of endothelial sprouting mediated by pro-angiogenic signaling. Microcirculation 2021; 29:e12744. [PMID: 34890488 PMCID: PMC9285777 DOI: 10.1111/micc.12744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 11/04/2021] [Accepted: 12/01/2021] [Indexed: 11/30/2022]
Abstract
Objective We aim to quantitatively characterize the crosstalk between VEGF‐ and FGF‐mediated angiogenic signaling and endothelial sprouting, to gain mechanistic insights and identify novel therapeutic strategies. Methods We constructed an experimentally validated hybrid agent‐based mathematical model that characterizes endothelial sprouting driven by FGF‐ and VEGF‐mediated signaling. We predicted the total sprout length, number of sprouts, and average length by the mono‐ and co‐stimulation of FGF and VEGF. Results The experimentally fitted and validated model predicts that FGF induces stronger angiogenic responses in the long‐term compared with VEGF stimulation. Also, FGF plays a dominant role in the combination effects in endothelial sprouting. Moreover, the model suggests that ERK and Akt pathways and cellular responses contribute differently to the sprouting process. Last, the model predicts that the strategies to modulate endothelial sprouting are context‐dependent, and our model can identify potential effective pro‐ and anti‐angiogenic targets under different conditions and study their efficacy. Conclusions The model provides detailed mechanistic insight into VEGF and FGF interactions in sprouting angiogenesis. More broadly, this model can be utilized to identify targets that influence angiogenic signaling leading to endothelial sprouting and to study the effects of pro‐ and anti‐angiogenic therapies.
Collapse
Affiliation(s)
- Min Song
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA
| | - Stacey D Finley
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA.,Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California, USA.,Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, California, USA
| |
Collapse
|
2
|
Song M, Finley SD. ERK and Akt exhibit distinct signaling responses following stimulation by pro-angiogenic factors. Cell Commun Signal 2020; 18:114. [PMID: 32680529 PMCID: PMC7368799 DOI: 10.1186/s12964-020-00595-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 05/11/2020] [Indexed: 02/07/2023] Open
Abstract
Background Angiogenesis plays an important role in the survival of tissues, as blood vessels provide oxygen and nutrients required by the resident cells. Thus, targeting angiogenesis is a prominent strategy in many different settings, including both tissue engineering and cancer treatment. However, not all of the approaches that modulate angiogenesis lead to successful outcomes. Angiogenesis-based therapies primarily target pro-angiogenic factors such as vascular endothelial growth factor-A (VEGF) or fibroblast growth factor (FGF) in isolation, and there is a limited understanding of how these promoters combine together to stimulate angiogenesis. Targeting one pathway could be insufficient, as alternative pathways may compensate, diminishing the overall effect of the treatment strategy. Methods To gain mechanistic insight and identify novel therapeutic strategies, we have developed a detailed mathematical model to quantitatively characterize the crosstalk of FGF and VEGF intracellular signaling. The model focuses on FGF- and VEGF-induced mitogen-activated protein kinase (MAPK) signaling to promote cell proliferation and the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathway, which promotes cell survival and migration. We fit the model to published experimental datasets that measure phosphorylated extracellular regulated kinase (pERK) and Akt (pAkt) upon FGF or VEGF stimulation. We validate the model with separate sets of data. Results We apply the trained and validated mathematical model to characterize the dynamics of pERK and pAkt in response to the mono- and co-stimulation by FGF and VEGF. The model predicts that for certain ranges of ligand concentrations, the maximum pERK level is more responsive to changes in ligand concentration compared to the maximum pAkt level. Also, the combination of FGF and VEGF indicates a greater effect in increasing the maximum pERK compared to the summation of individual effects, which is not seen for maximum pAkt levels. In addition, our model identifies the influential species and kinetic parameters that specifically modulate the pERK and pAkt responses, which represent potential targets for angiogenesis-based therapies. Conclusions Overall, the model predicts the combination effects of FGF and VEGF stimulation on ERK and Akt quantitatively and provides a framework to mechanistically explain experimental results and guide experimental design. Thus, this model can be utilized to study the effects of pro- and anti-angiogenic therapies that particularly target ERK and/or Akt activation upon stimulation with FGF and VEGF. Video Abstract
Collapse
Affiliation(s)
- Min Song
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, USA
| | - Stacey D Finley
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, USA. .,Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, USA. .,Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA.
| |
Collapse
|
3
|
Nilasaroya A, Kop AM, Morrison DA. Heparin-functionalized hydrogels as growth factor-signaling substrates. J Biomed Mater Res A 2020; 109:374-384. [PMID: 32515102 DOI: 10.1002/jbm.a.37030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/29/2020] [Accepted: 05/07/2020] [Indexed: 01/08/2023]
Abstract
Tuneable, bioactive hydrogels present an attractive option as cell-instructive substrates for tissue regeneration. Properties mimicking the extracellular matrix at the site of injury are sought after, in particular the ability to regulate growth factors that are key to the regeneration process. This study demonstrates the successful formation of hydrogels with heparin functionalities and fibroblast growth factor-2 (FGF-2). Poly(2-hydroxyethyl methacrylate)-heparin hydrogels were capable of retaining FGF-2 by specific binding to heparin and subsequently showed sustained presentation of the growth factor to mesenchymal stromal cells (MSC). Heparin acted as stable anchoring molecules for FGF-2 on the substrate and the synergistic effect of the ensuing heparin-FGF-2 complex was evident in supporting long term cell growth. The presence of heparin during 3D scaffold formation was also found to introduce surface roughness and microporosity to the resulting hydrogels. While FGF-2 has been known to encourage MSC growth and maintain their multilineage potential, other heparin-binding ligands such as bone morphogenetic proteins are potent differentiation stimuli for MSC. Therefore preserving MSC multipotency or a push toward a differentiation pathway may be pursued by the choice of ligand applied to and bound by the heparin functionalities on the current substrate.
Collapse
Affiliation(s)
- Anastasia Nilasaroya
- Department of Medical Engineering and Physics, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Alan Matthew Kop
- Department of Medical Engineering and Physics, Royal Perth Hospital, Perth, Western Australia, Australia
| | - David Anthony Morrison
- Department of Medical Engineering and Physics, Royal Perth Hospital, Perth, Western Australia, Australia
| |
Collapse
|
4
|
Song M, Finley SD. Mechanistic insight into activation of MAPK signaling by pro-angiogenic factors. BMC SYSTEMS BIOLOGY 2018; 12:145. [PMID: 30591051 PMCID: PMC6307205 DOI: 10.1186/s12918-018-0668-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 11/30/2018] [Indexed: 01/14/2023]
Abstract
Background Angiogenesis is important in physiological and pathological conditions, as blood vessels provide nutrients and oxygen needed for tissue growth and survival. Therefore, targeting angiogenesis is a prominent strategy in both tissue engineering and cancer treatment. However, not all of the approaches to promote or inhibit angiogenesis lead to successful outcomes. Angiogenesis-based therapies primarily target pro-angiogenic factors such as vascular endothelial growth factor-A (VEGF) or fibroblast growth factor (FGF) in isolation. However, pre-clinical and clinical evidence shows these therapies often have limited effects. To improve therapeutic strategies, including targeting FGF and VEGF in combination, we need a quantitative understanding of the how the promoters combine to stimulate angiogenesis. Results In this study, we trained and validated a detailed mathematical model to quantitatively characterize the crosstalk of FGF and VEGF intracellular signaling. This signaling is initiated by FGF binding to the FGF receptor 1 (FGFR1) and heparan sulfate glycosaminoglycans (HSGAGs) or VEGF binding to VEGF receptor 2 (VEGFR2) to promote downstream signaling. The model focuses on FGF- and VEGF-induced mitogen-activated protein kinase (MAPK) signaling and phosphorylation of extracellular regulated kinase (ERK), which promotes cell proliferation. We apply the model to predict the dynamics of phosphorylated ERK (pERK) in response to the stimulation by FGF and VEGF individually and in combination. The model predicts that FGF and VEGF have differential effects on pERK. Additionally, since VEGFR2 upregulation has been observed in pathological conditions, we apply the model to investigate the effects of VEGFR2 density and trafficking parameters. The model predictions show that these parameters significantly influence the response to VEGF stimulation. Conclusions The model agrees with experimental data and is a framework to synthesize and quantitatively explain experimental studies. Ultimately, the model provides mechanistic insight into FGF and VEGF interactions needed to identify potential targets for pro- or anti-angiogenic therapies. Electronic supplementary material The online version of this article (10.1186/s12918-018-0668-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Min Song
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA
| | - Stacey D Finley
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA. .,Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California, USA. .,Department of Biological Sciences, Computational Biology section, University of Southern California, 1042 Downey Way, CRB 140, Los Angeles, CA, 90089, USA.
| |
Collapse
|
5
|
Ikpegbu E, Basta L, Clements DN, Fleming R, Vincent TL, Buttle DJ, Pitsillides AA, Staines KA, Farquharson C. FGF-2 promotes osteocyte differentiation through increased E11/podoplanin expression. J Cell Physiol 2018; 233:5334-5347. [PMID: 29215722 PMCID: PMC5900964 DOI: 10.1002/jcp.26345] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 11/29/2017] [Indexed: 01/15/2023]
Abstract
E11/podoplanin is critical in the early stages of osteoblast‐to‐osteocyte transitions (osteocytogenesis), however, the upstream events which regulate E11 expression are unknown. The aim of this study was to examine the effects of FGF‐2 on E11‐mediated osteocytogenesis and to reveal the nature of the underlying signaling pathways regulating this process. Exposure of MC3T3 osteoblast‐like cells and murine primary osteoblasts to FGF‐2 (10 ng/ml) increased E11 mRNA and protein expression (p < 0.05) after 4, 6, and 24 hr. FGF‐2 induced changes in E11 expression were also accompanied by significant (p < 0.01) increases in Phex and Dmp1 (osteocyte markers) expression and decreases in Col1a1, Postn, Bglap, and Alpl (osteoblast markers) expression. Immunofluorescent microscopy revealed that FGF‐2 stimulated E11 expression, facilitated the translocation of E11 toward the cell membrane, and subsequently promoted the formation of osteocyte‐like dendrites in MC3T3 and primary osteoblasts. siRNA knock down of E11 expression achieved >70% reduction of basal E11 mRNA expression (p < 0.05) and effectively abrogated FGF‐2‐related changes in E11 expression and dendrite formation. FGF‐2 strongly activated the ERK signaling pathway in osteoblast‐like cells but inhibition of this pathway did not block the ability of FGF‐2 to enhance E11 expression or to promote acquisition of the osteocyte phenotype. The results of this study highlight a novel mechanism by which FGF‐2 can regulate osteoblast differentiation and osteocyte formation. Specifically, the data suggests that FGF‐2 promotes osteocytogenesis through increased E11 expression and further studies will identify if this regulatory pathway is essential for bone development and maintenance in health and disease.
Collapse
Affiliation(s)
- Ekele Ikpegbu
- Roslin Institute and R(D)SVS, The University of Edinburgh, Edinburgh, UK.,Michael Okpara University of Agriculture, Abia, Nigeria
| | - Lena Basta
- Roslin Institute and R(D)SVS, The University of Edinburgh, Edinburgh, UK
| | - Dylan N Clements
- Roslin Institute and R(D)SVS, The University of Edinburgh, Edinburgh, UK
| | - Robert Fleming
- Roslin Institute and R(D)SVS, The University of Edinburgh, Edinburgh, UK
| | - Tonia L Vincent
- Arthritis Research UK Centre for Osteoarthritis Pathogenesis, Kennedy Institute of Rheumatology, University of Oxford, Oxford, UK
| | - David J Buttle
- Department of Infection, Immunity & Cardiovascular Disease, The University of Sheffield Medical School, Sheffield, UK
| | | | | | - Colin Farquharson
- Roslin Institute and R(D)SVS, The University of Edinburgh, Edinburgh, UK
| |
Collapse
|
6
|
Xeno-Free Strategies for Safe Human Mesenchymal Stem/Stromal Cell Expansion: Supplements and Coatings. Stem Cells Int 2017; 2017:6597815. [PMID: 29158740 PMCID: PMC5660800 DOI: 10.1155/2017/6597815] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 08/01/2017] [Indexed: 12/13/2022] Open
Abstract
Human mesenchymal stem/stromal cells (hMSCs) have generated great interest in regenerative medicine mainly due to their multidifferentiation potential and immunomodulatory role. Although hMSC can be obtained from different tissues, the number of available cells is always low for clinical applications, thus requiring in vitro expansion. Most of the current protocols for hMSC expansion make use of fetal bovine serum (FBS) as a nutrient-rich supplement. However, regulatory guidelines encourage novel xeno-free alternatives to define safer and standardized protocols for hMSC expansion that preserve their intrinsic therapeutic potential. Since hMSCs are adherent cells, the attachment surface and cell-adhesive components also play a crucial role on their successful expansion. This review focuses on the advantages/disadvantages of FBS-free media and surfaces/coatings that avoid the use of animal serum, overcoming ethical issues and improving the expansion of hMSC for clinical applications in a safe and reproducible way.
Collapse
|
7
|
Moscaroli A, Jones G, Lühmann T, Meinel L, Wälti S, Blanc A, Fischer E, Hilbert M, Schibli R, Béhé M. Radiolabeled 111In-FGF-2 Is Suitable for In Vitro/Ex Vivo Evaluations and In Vivo Imaging. Mol Pharm 2017; 14:639-648. [PMID: 28221043 DOI: 10.1021/acs.molpharmaceut.6b00913] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Fibroblast growth factor-2 (FGF-2) is a potent modulator of cell growth and regulation, with improper FGF-2 signaling being involved in impaired responses to injury or even cancer. Therefore, the exploitation of FGF-2 as a therapeutic drives the prerequisite for effective insight into drug disposition kinetics. In this article, we present an 111In-radiolabeled FGF-2 derivative for noninvasive imaging in small animals deploying single photon emission tomography (SPECT). 111In-FGF-2 is equally well suitable for in vitro and ex vivo investigations as 125I-FGF-2. Furthermore, 111In-FGF-2 permits the performance of in vivo imaging, for example for the analysis of FGF-2 containing pharmaceutical formulations in developmental or preclinical stages. 111In-FGF-2 had affinity for the low-molecular-weight heparin enoxaparin identical to that of unlabeled FGF-2 (Kd: 0.6 ± 0.07 μM and 0.33 ± 0.03 μM, respectively) as assessed by isothermal titration calorimetry. The binding of 111In-FGF-2 to heparan sulfate proteoglycans (HPSGs) and the biological activity were comparable to those of unlabeled FGF-2, with EC50 values of 12 ± 2 pM and 25 ± 6 pM, respectively. In vivo biodistribution in healthy nude mice indicated a predominant accumulation of 111In-FGF-2 in filtering organs and minor uptake in the retina and the salivary and pituitary glands, which was confirmed by SPECT imaging. Therefore, 111In-FGF-2 is a valid tracer for future noninvasive animal imaging of FGF-2 in pharmaceutical development.
Collapse
Affiliation(s)
- Alessandra Moscaroli
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute , 5232 Villigen PSI, Switzerland
| | - Gabriel Jones
- Institute for Pharmacy and Food Chemistry, University of Wurzburg , 97074 Wurzburg, Germany
| | - Tessa Lühmann
- Institute for Pharmacy and Food Chemistry, University of Wurzburg , 97074 Wurzburg, Germany
| | - Lorenz Meinel
- Institute for Pharmacy and Food Chemistry, University of Wurzburg , 97074 Wurzburg, Germany
| | - Stephanie Wälti
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich , 8092 Zurich, Switzerland
| | - Alain Blanc
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute , 5232 Villigen PSI, Switzerland
| | - Eliane Fischer
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute , 5232 Villigen PSI, Switzerland
| | - Manuel Hilbert
- Laboratory of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institute , 5232 Villigen PSI, Switzerland
| | - Roger Schibli
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute , 5232 Villigen PSI, Switzerland.,Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich , 8092 Zurich, Switzerland
| | - Martin Béhé
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute , 5232 Villigen PSI, Switzerland
| |
Collapse
|
8
|
Lakshmanan R, Kumaraswamy P, Krishnan UM, Sethuraman S. Engineering a growth factor embedded nanofiber matrix niche to promote vascularization for functional cardiac regeneration. Biomaterials 2016; 97:176-95. [DOI: 10.1016/j.biomaterials.2016.02.033] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 02/17/2016] [Accepted: 02/22/2016] [Indexed: 12/20/2022]
|
9
|
NMR structural determination of unique invertebrate glycosaminoglycans endowed with medical properties. Carbohydr Res 2015; 413:41-50. [DOI: 10.1016/j.carres.2015.05.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 05/13/2015] [Accepted: 05/15/2015] [Indexed: 01/29/2023]
|
10
|
Ribatti D, Nico B, Vacca A. Multiple myeloma as a model for the role of bone marrow niches in the control of angiogenesis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 314:259-82. [PMID: 25619720 DOI: 10.1016/bs.ircmb.2014.10.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Bone marrow (BM) contains hematopoietic stem cells (HSCs) and nonhematopoietic cells. HSCs give rise to all types of mature blood cells, while the nonhematopoietic component includes osteoblasts/osteoclasts, endothelial cells (ECs), endothelial progenitor cells (EPCs), and mesenchymal stem cells (MSCs). These cells form specialized "niches" which are close to the vasculature ("vascular niche") or to the endosteum ("osteoblast niche"). The "vascular niche", rich in blood vessels where ECs and mural cells (pericytes and smooth muscle cells), create a microenvironment affecting the behavior of several stem and progenitor cells. The vessel wall acts as an independent niche for the recruitment of EPCs and MSCs. This chapter will focus on the description of the role of BM niches in the control of angiogenesis occurring during multiple myeloma progression.
Collapse
Affiliation(s)
- Domenico Ribatti
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, University of Bari Medical School, Bari, Italy; National Cancer Institute "Giovanni Paolo II", Bari, Italy
| | - Beatrice Nico
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, University of Bari Medical School, Bari, Italy
| | - Angelo Vacca
- Department of Internal Medicine and Oncology, University of Bari Medical School, Bari, Italy
| |
Collapse
|
11
|
Cappariello A, Maurizi A, Veeriah V, Teti A. Reprint of: The Great Beauty of the osteoclast. Arch Biochem Biophys 2014; 561:13-21. [DOI: 10.1016/j.abb.2014.08.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 06/02/2014] [Accepted: 06/05/2014] [Indexed: 12/17/2022]
|
12
|
Cappariello A, Maurizi A, Veeriah V, Teti A. The Great Beauty of the osteoclast. Arch Biochem Biophys 2014; 558:70-8. [DOI: 10.1016/j.abb.2014.06.017] [Citation(s) in RCA: 148] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 06/02/2014] [Accepted: 06/05/2014] [Indexed: 12/12/2022]
|
13
|
Mario Cheong GL, Lim KS, Jakubowicz A, Martens PJ, Poole-Warren LA, Green RA. Conductive hydrogels with tailored bioactivity for implantable electrode coatings. Acta Biomater 2014; 10:1216-26. [PMID: 24365707 DOI: 10.1016/j.actbio.2013.12.032] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 11/27/2013] [Accepted: 12/16/2013] [Indexed: 11/19/2022]
Abstract
The development of high-resolution neuroprosthetics has driven the need for better electrode materials. Approaches to achieve both electrical and mechanical improvements have included the development of hydrogel and conducting polymer composites. However, these composites have limited biological interaction, as they are often composed of synthetic polymers or non-ideal biological polymers, which lack the required elements for biorecognition. This study explores the covalent incorporation of bioactive molecules within a conducting hydrogel (CH). The CH was formed from the biosynthetic co-hydrogel poly(vinyl alcohol)-heparin and the conductive polymer (CP), poly(3,4-ethylene dioxythiophene). Adhesive biomolecules sericin and gelatin were covalently incorporated via methacrylate crosslinking within the CH. Electrical properties of the bioactive CH were assessed, and it was shown that the polar biomolecules improved charge transfer. The bioactivity of heparin within the hybrid assessed by examining stimulation of B-lymphocyte (BaF3) proliferation showed that bioactivity was retained after electropolymerization of the CP through the hydrogel. Similarly, incorporation of sericin and gelatin in the CH promoted neural cell adhesion and proliferation, with only small percentages (⩽ 2 wt.%) required to achieve optimal results. Sericin provided the best support for the outgrowth of neural processes, and 1 wt.% was sufficient to facilitate adhesion and differentiation of neurons. The drug delivery capability of CH was shown through incorporation of nerve growth factor during polymer fabrication. NGF was delivered to the target cells, resulting in outgrowth of neural processes. The CH system is a flexible technology platform, which can be tailored to covalently incorporate bioactive protein sequences and deliver mobile water-soluble drug molecules.
Collapse
Affiliation(s)
- G L Mario Cheong
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Khoon S Lim
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Anais Jakubowicz
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Penny J Martens
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Laura A Poole-Warren
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Rylie A Green
- Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, NSW 2052, Australia.
| |
Collapse
|
14
|
Chim SM, Tickner J, Chow ST, Kuek V, Guo B, Zhang G, Rosen V, Erber W, Xu J. Angiogenic factors in bone local environment. Cytokine Growth Factor Rev 2013; 24:297-310. [DOI: 10.1016/j.cytogfr.2013.03.008] [Citation(s) in RCA: 173] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 03/26/2013] [Indexed: 01/11/2023]
|
15
|
Lim TC, Rokkappanavar S, Toh WS, Wang LS, Kurisawa M, Spector M. Chemotactic recruitment of adult neural progenitor cells into multifunctional hydrogels providing sustained SDF-1α release and compatible structural support. FASEB J 2012. [PMID: 23193174 DOI: 10.1096/fj.12-221515] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Without chemotactic cues and structural support, cavitary brain lesions typically fail to recruit endogenous neural progenitor cells (NPCs). Toward resolving this, we engineered multifunctional biomaterials comprising injectable gelatin-hydroxyphenylpropionic acid (Gtn-HPA) hydrogels and dextran sulfate/chitosan polyelectrolyte complex nanoparticles (PCNs) that delivered stromal cell-derived factor-1α (SDF-1α). Over 7 d of interface with in vitro tissue simulant containing adult rat hippocampal NPCs (aNPCs) and their neuronal progeny, Gtn-HPA/SDF-1α-PCN hydrogels promoted chemotactic recruitment to enhance infiltration of aNPCs by 3- to 45-fold relative to hydrogels that lacked SDF-1α or vehicles to sustain SDF-1α release. When cross-linked with 0.85-0.95 mM HO, Gtn-HPA/SDF-1α-PCN hydrogels provided optimally permissive structural support for migration of aNPCs. Specific matrix metalloproteinase (MMP) inhibitors revealed that 42, 30, and 55% of cell migration into Gtn-HPA/SDF-1α-PCN hydrogels involved MMP-2, 3, and 9, respectively, demonstrating the hydrogels to be compatible toward homing endogenous NPCs, given their expression of similar MMPs. Interestingly, PCNs utilized FGF-2 found in situ to induce chemokinesis, potentiate SDF-1α chemotactic recruitment, and increase proliferation of recruited cells, which collectively orchestrated a higher number of migrated aNPCs. Overall, Gtn-HPA/SDF-1α-PCN hydrogels prove to be promising biomaterials for injection into cavitary brain lesions to recruit endogenous NPCs and enhance neural tissue repair/regeneration.
Collapse
Affiliation(s)
- Teck Chuan Lim
- Tissue Engineering Laboratories, VA Boston Healthcare System, Mail Stop 151 Research, 150 S. Huntington Ave., Boston, MA 02130, USA
| | | | | | | | | | | |
Collapse
|
16
|
Simón-Yarza T, Formiga FR, Tamayo E, Pelacho B, Prosper F, Blanco-Prieto MJ. Vascular endothelial growth factor-delivery systems for cardiac repair: an overview. Am J Cancer Res 2012; 2:541-52. [PMID: 22737191 PMCID: PMC3381347 DOI: 10.7150/thno.3682] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 12/23/2011] [Indexed: 11/05/2022] Open
Abstract
Since the discovery of the Vascular Endothelial Growth Factor (VEGF) and its leading role in the angiogenic process, this has been seen as a promising molecule for promoting neovascularization in the infarcted heart. However, even though several clinical trials were initiated, no therapeutic effects were observed, due in part to the short half life of this factor when administered directly to the tissue. In this context, drug delivery systems appear to offer a promising strategy to overcome limitations in clinical trials of VEGF.The aim of this paper is to review the principal drug delivery systems that have been developed to administer VEGF in cardiovascular disease. Studies published in the last 5 years are reviewed and the main features of these systems are explained. The tissue engineering concept is introduced as a therapeutic alternative that holds promise for the near future.
Collapse
|
17
|
Nilasaroya A, Martens PJ, Whitelock JM. Enzymatic degradation of heparin-modified hydrogels and its effect on bioactivity. Biomaterials 2012; 33:5534-40. [PMID: 22575836 DOI: 10.1016/j.biomaterials.2012.04.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Accepted: 04/08/2012] [Indexed: 01/02/2023]
Abstract
The extracellular matrix is continually remodelled by the action of various enzymes such as heparanase, which specifically targets heparan sulfate (HS) and is found in human platelets at high levels. The activity of heparin-containing hydrogels following incubation with platelet extract (PE) was investigated in order to simulate the responses that might occur when the hydrogels, as tissue engineered scaffolds, come in contact with blood products at the site of an injury. The heparanase activity of PE on heparin, used as a model of HS, was confirmed by the decrease in molecular weight. PE treatment diminished heparin's anticoagulation property but increased its FGF-2 signalling activity, suggesting that the PE's heparanase activity cleaves at the 3-O-sulfated glucosamine to produce large fragments that can signal cell receptors. The dual effect observed when poly(vinyl alcohol)/heparin co-hydrogels were incubated with PE supports the hypothesis of platelets having the capacity to limit anticoagulation and thus promote blood clot formation, which may be critical in the process of tissue repair.
Collapse
Affiliation(s)
- Anastasia Nilasaroya
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
| | | | | |
Collapse
|
18
|
Kraushaar DC, Rai S, Condac E, Nairn A, Zhang S, Yamaguchi Y, Moremen K, Dalton S, Wang L. Heparan sulfate facilitates FGF and BMP signaling to drive mesoderm differentiation of mouse embryonic stem cells. J Biol Chem 2012; 287:22691-700. [PMID: 22556407 DOI: 10.1074/jbc.m112.368241] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Heparan sulfate (HS) has been implicated in regulating cell fate decisions during differentiation of embryonic stem cells (ESCs) into advanced cell types. However, the necessity and the underlying molecular mechanisms of HS in early cell lineage differentiation are still largely unknown. In this study, we examined the potential of EXT1(-/-) mouse ESCs (mESCs), that are deficient in HS, to differentiate into primary germ layer cells. We observed that EXT1(-/-) mESCs lost their differentiation competence and failed to differentiate into Pax6(+)-neural precursor cells and mesodermal cells. More detailed analyses highlighted the importance of HS for the induction of Brachyury(+) pan-mesoderm as well as normal gene expression associated with the dorso-ventral patterning of mesoderm. Examination of developmental cell signaling revealed that EXT1 ablation diminished FGF and BMP but not Wnt signaling. Furthermore, restoration of FGF and BMP signaling each partially rescued mesoderm differentiation defects. We further show that BMP4 is more prone to degradation in EXT1(-/-) mESCs culture medium compared with that of wild type cells. Therefore, our data reveal that HS stabilizes BMP ligand and thereby maintains the BMP signaling output required for normal mesoderm differentiation. In summary, our study demonstrates that HS is required for ESC pluripotency, in particular lineage specification into mesoderm through facilitation of FGF and BMP signaling.
Collapse
Affiliation(s)
- Daniel C Kraushaar
- Complex Carbohydrate Research Center and Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Kim JH, Jiang S, Elwell CA, Engel JN. Chlamydia trachomatis co-opts the FGF2 signaling pathway to enhance infection. PLoS Pathog 2011; 7:e1002285. [PMID: 21998584 PMCID: PMC3188521 DOI: 10.1371/journal.ppat.1002285] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 08/10/2011] [Indexed: 12/12/2022] Open
Abstract
The molecular details of Chlamydia trachomatis binding, entry, and spread are incompletely understood, but heparan sulfate proteoglycans (HSPGs) play a role in the initial binding steps. As cell surface HSPGs facilitate the interactions of many growth factors with their receptors, we investigated the role of HSPG-dependent growth factors in C. trachomatis infection. Here, we report a novel finding that Fibroblast Growth Factor 2 (FGF2) is necessary and sufficient to enhance C. trachomatis binding to host cells in an HSPG-dependent manner. FGF2 binds directly to elementary bodies (EBs) where it may function as a bridging molecule to facilitate interactions of EBs with the FGF receptor (FGFR) on the cell surface. Upon EB binding, FGFR is activated locally and contributes to bacterial uptake into non-phagocytic cells. We further show that C. trachomatis infection stimulates fgf2 transcription and enhances production and release of FGF2 through a pathway that requires bacterial protein synthesis and activation of the Erk1/2 signaling pathway but that is independent of FGFR activation. Intracellular replication of the bacteria results in host proteosome-mediated degradation of the high molecular weight (HMW) isoforms of FGF2 and increased amounts of the low molecular weight (LMW) isoforms, which are released upon host cell death. Finally, we demonstrate the in vivo relevance of these findings by showing that conditioned medium from C. trachomatis infected cells is enriched for LMW FGF2, accounting for its ability to enhance C. trachomatis infectivity in additional rounds of infection. Together, these results demonstrate that C. trachomatis utilizes multiple mechanisms to co-opt the host cell FGF2 pathway to enhance bacterial infection and spread. Chlamydia trachomatis is an obligate intracellular bacterium that is an important cause of human disease, including sexually transmitted diseases and acquired blindness in developing countries. The inability to carry out conventional genetic manipulations limits our understanding of the mechanisms of C. trachomatis binding, entry, and spread. Previous studies have shown that heparan sulfate proteoglycans (HSPGs) play a role in early binding events. As cell surface HSPGs facilitate the interactions of many growth factors with their receptors, we investigated whether HSPG-associated growth factors affect C. trachomatis binding or entry. Here, we report the novel finding that Fibroblast Growth Factor 2 (FGF2), a ubiquitously expressed growth factor, enhances C. trachomatis binding to host cells in an HSPG-dependent manner. Furthermore, C. trachomatis infection stimulates production and release of FGF2 through distinct signaling pathways. Released FGF2 is sufficient to enhance the subsequent rounds of infection. Together, these results demonstrate that C. trachomatis utilizes multiple mechanisms to co-opt the host cell FGF2 pathway that sets up a positive feedback loop to enhance bacterial infection and spread.
Collapse
Affiliation(s)
- Jung Hwa Kim
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
- Microbial Pathogenesis and Host Defense Program, University of California San Francisco, San Francisco, California, United States of America
| | - Shaobo Jiang
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
- Microbial Pathogenesis and Host Defense Program, University of California San Francisco, San Francisco, California, United States of America
| | - Cherilyn A. Elwell
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
- Microbial Pathogenesis and Host Defense Program, University of California San Francisco, San Francisco, California, United States of America
| | - Joanne N. Engel
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
- Microbial Pathogenesis and Host Defense Program, University of California San Francisco, San Francisco, California, United States of America
- Department of Microbiology and Immunology, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
| |
Collapse
|
20
|
Dreyfuss JL, Regatieri CV, Jarrouge TR, Cavalheiro RP, Sampaio LO, Nader HB. Heparan sulfate proteoglycans: structure, protein interactions and cell signaling. AN ACAD BRAS CIENC 2010; 81:409-29. [PMID: 19722012 DOI: 10.1590/s0001-37652009000300007] [Citation(s) in RCA: 171] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Accepted: 10/08/2008] [Indexed: 01/18/2023] Open
Abstract
Heparan sulfate proteoglycans are ubiquitously found at the cell surface and extracellular matrix in all the animal species. This review will focus on the structural characteristics of the heparan sulfate proteoglycans related to protein interactions leading to cell signaling. The heparan sulfate chains due to their vast structural diversity are able to bind and interact with a wide variety of proteins, such as growth factors, chemokines, morphogens, extracellular matrix components, enzymes, among others. There is a specificity directing the interactions of heparan sulfates and target proteins, regarding both the fine structure of the polysaccharide chain as well precise protein motifs. Heparan sulfates play a role in cellular signaling either as receptor or co-receptor for different ligands, and the activation of downstream pathways is related to phosphorylation of different cytosolic proteins either directly or involving cytoskeleton interactions leading to gene regulation. The role of the heparan sulfate proteoglycans in cellular signaling and endocytic uptake pathways is also discussed.
Collapse
Affiliation(s)
- Juliana L Dreyfuss
- Departamento de Bioquímica, Universidade Federal de São Paulo, São Paulo, SP, Brasil
| | | | | | | | | | | |
Collapse
|
21
|
Abstract
We present many examples of surface engineered polymeric biomaterials with nanosize modified layers, controlled protein adsorption, and cellular interactions potentially applicable for tissue and/or blood contacting devices, scaffolds for cell culture and tissue engineering, biosensors, biological microchips as well as approaches to their preparation.
Collapse
|
22
|
Nilasaroya A, Poole-Warren LA, Whitelock JM, Jo Martens P. Structural and functional characterisation of poly(vinyl alcohol) and heparin hydrogels. Biomaterials 2008; 29:4658-64. [DOI: 10.1016/j.biomaterials.2008.08.011] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Accepted: 08/20/2008] [Indexed: 12/31/2022]
|
23
|
Tholozan FMD, Gribbon C, Li Z, Goldberg MW, Prescott AR, McKie N, Quinlan RA. FGF-2 release from the lens capsule by MMP-2 maintains lens epithelial cell viability. Mol Biol Cell 2007; 18:4222-31. [PMID: 17699594 PMCID: PMC2043559 DOI: 10.1091/mbc.e06-05-0416] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The lens is an avascular tissue, separated from the aqueous and vitreous humors by its own extracellular matrix, the lens capsule. Here we demonstrate that the lens capsule is a source of essential survival factors for lens epithelial cells. Primary and immortalized lens epithelial cells survive in low levels of serum and are resistant to staurosporine-induced apoptosis when they remain in contact with the lens capsule. Physical contact with the capsule is required for maximal resistance to stress. The lens capsule is also a source of soluble factors including fibroblast growth factor 2 (FGF-2) and perlecan, an extracellular matrix component that enhances FGF-2 activity. Matrix metalloproteinase 2 (MMP-2) inhibition as well as MMP-2 pretreatment of lens capsules greatly reduced the protective effect of the lens capsule, although this could be largely reversed by the addition of either conditioned medium or recombinant FGF-2. These data suggest that FGF-2 release from the lens capsule by MMP-2 is essential to lens epithelial cell viability and survival.
Collapse
Affiliation(s)
- Frederique M D Tholozan
- School of Biological and Biomedical Sciences, Durham University, Durham DH1 3LE, United Kingdom
| | | | | | | | | | | | | |
Collapse
|
24
|
Chung HJ, Park TG. Surface engineered and drug releasing pre-fabricated scaffolds for tissue engineering. Adv Drug Deliv Rev 2007; 59:249-62. [PMID: 17482310 DOI: 10.1016/j.addr.2007.03.015] [Citation(s) in RCA: 312] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2006] [Accepted: 03/28/2007] [Indexed: 01/08/2023]
Abstract
A wide range of polymeric scaffolds have been intensively studied for use as implantable and temporal devices in tissue engineering. Biodegradable and biocompatible scaffolds having a highly open porous structure and good mechanical strength are needed to provide an optimal microenvironment for cell proliferation, migration, and differentiation, and guidance for cellular in-growth from host tissue. A variety of natural and synthetic polymeric scaffolds can be fabricated in the form of a solid foam, nanofibrous matrix, microsphere, or hydrogel. Biodegradable porous scaffolds can be surface engineered to provide an extracellular matrix mimicking environment for better cell adhesion and tissue in-growth. Furthermore, scaffolds can be designed to release bioactive molecules, such as growth factors, DNA, or drugs, in a sustained manner to facilitate tissue regeneration. This paper reviews the current status of surface engineered and drug releasing scaffolds for tissue engineering.
Collapse
Affiliation(s)
- Hyun Jung Chung
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | | |
Collapse
|
25
|
Suarez ER, Nohara AS, Mataveli FD, de Matos LL, Nader HB, Pinhal MAS. Glycosaminoglycan synthesis and shedding induced by growth factors are cell and compound specific. Growth Factors 2007; 25:50-9. [PMID: 17454150 DOI: 10.1080/08977190701272701] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The interactions between growth factors and sulphated glycosaminoglycans (GAG) have been extensively studied. The aim of this study is to investigate if growth factors would show specificity of action on the synthesis and shedding of sulphated GAG, using two different cell lines: endothelial and smooth muscle cells. The cells were grown in the presence or absence of growth factors: EGF, FGF2, VEGF121, VEGF165. Transfection assays were also performed using recombinant pcDNA3.1, containing VEGF165 cDNA. In order to analyse the different types of GAG the cells were metabolically labelled with [(35)S]-sulphate. At low doses, VEGF121 was the only growth factor able to increase both the synthesis and secretion of heparan sulphate (HS) in endothelial cells. Over expression of VEGF165 stimulated HS synthesis in both cells. The combined results showed that growth factors affect GAG synthesis in a cell specific and dose dependent manner.
Collapse
Affiliation(s)
- Eloah R Suarez
- Departamento de Bioquímica, Faculdade de Medicina, Fundação do ABC (FMABC), Av. Principe de Gales, 821, Santo André, SP, CEP 09060-650, Brazil
| | | | | | | | | | | |
Collapse
|
26
|
Berry D, Lynn DM, Berry E, Sasisekharan R, Langer R. Heparin localization and fine structure regulate Burkitt’s lymphoma growth. Biochem Biophys Res Commun 2006; 348:850-6. [PMID: 16904641 DOI: 10.1016/j.bbrc.2006.07.128] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2006] [Accepted: 07/18/2006] [Indexed: 11/15/2022]
Abstract
Burkitt's lymphoma (BL) is a B-cell malignancy associated with the Epstein-Barr virus (EBV). Mounting evidence has implicated heparan sulfate proteoglycans and heparan sulfate-like glycosaminoglycans (HSGAGs) in the initiation, severity, and progression of the malignancy. The importance of HSGAGs in regulating BL cell growth was therefore examined. Extracellular exogenous heparin inhibited cell growth >30%, while heparin internalized with poly(beta-amino ester)s promoted proliferation up to 58%. The growth-modulating effects of heparin and internalized heparin were dependent on cell surface HSGAGs, PI3K, and Erk/Mek. Treatment of cells with protamine sulfate or with heparinases potently inhibited proliferation, with the greatest effects induced by heparinase I. Cell surface HSGAGs therefore play an important role in regulating BL proliferation and may offer a potential target for therapeutic intervention.
Collapse
Affiliation(s)
- David Berry
- Harvard Medical School, Boston, MA 02215, USA
| | | | | | | | | |
Collapse
|
27
|
Dupree MA, Pollack SR, Levine EM, Laurencin CT. Fibroblast growth factor 2 induced proliferation in osteoblasts and bone marrow stromal cells: a whole cell model. Biophys J 2006; 91:3097-112. [PMID: 16861274 PMCID: PMC1578487 DOI: 10.1529/biophysj.106.087098] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Fibroblast growth factor 2 (FGF2) can enhance the proliferative capacity of bone and bone marrow stromal cells; however, the mechanisms behind this effect are not well described. We present a whole-cell kinetic model relating receptor-mediated binding, internalization, and processing of FGF2 to osteoblastic proliferative response. Focusing on one of the potential signaling complex stoichiometries, we utilized experimentally measured and modeled estimated rate constants to predict in vitro proliferation and distinguish between potential binding orders. We found that piecewise assemblage of a ternary signaling complex may occur in several ways depending on the local binding environment. Using experimental data of endocytosed FGF2 as a constraint, we have also shown evidence of potential multistep processes involved in heparan-sulfate proteoglycans-bound FGF2 release, internalization, and fragment formation in conjunction with the normal metabolism of the proteoglycan.
Collapse
Affiliation(s)
- Melissa A Dupree
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | | | | |
Collapse
|
28
|
Chu CL, Goerges AL, Nugent MA. Identification of common and specific growth factor binding sites in heparan sulfate proteoglycans. Biochemistry 2005; 44:12203-13. [PMID: 16142919 DOI: 10.1021/bi050241p] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The structural complexity within heparan sulfate has suggested that it contains multiple protein-specific binding sites. To evaluate the selectivity of growth factor binding to heparan sulfate, we conducted a detailed study of the intercompetition of fibroblast growth factor-2 (FGF-2) and heparin-binding epidermal growth factor-like growth factor (HB-EGF) binding to heparan sulfate (HS) on bovine aortic smooth muscle cells. Radioligand binding assays were conducted, and an analytical method was developed for determining the apparent binding constants and numbers of specific and shared binding sites within HS. These studies revealed the presence of two general classes of HS-binding sites for FGF-2 and HB-EGF. The major class (approximately 10(6) sites per cell) was able to bind to either growth factor with relatively low affinity (K(d) = 12 and 44 nM for FGF-2 and HB-EGF, respectively) and was termed "common" binding sites. However, both FGF-2 and HB-EGF also showed specific high affinity (0.6 and 6.1 nM for FGF-2 and HB-EGF, respectively) binding to a minor subset (118,000 and 28,000 sites per cell for FGF-2 and HB-EGF, respectively) of "unique" binding sites, which were unable to bind the other growth factor. These studies indicate that growth factor binding to HS involves multiple binding sites of variable affinity, density, and selectivity. The approach outlined in this study could be applied to aid in the evaluation of the relative biological roles of these selective and nonselective growth factor binding domains within HS.
Collapse
Affiliation(s)
- Chia Lin Chu
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118, USA
| | | | | |
Collapse
|
29
|
Berry D, Lynn DM, Sasisekharan R, Langer R. Poly(beta-amino ester)s promote cellular uptake of heparin and cancer cell death. ACTA ACUST UNITED AC 2004; 11:487-98. [PMID: 15123243 DOI: 10.1016/j.chembiol.2004.03.023] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2003] [Revised: 01/06/2004] [Accepted: 01/09/2004] [Indexed: 11/23/2022]
Abstract
Heparin/heparan sulfate-like glycosaminoglycans (HSGAGs) are involved in diverse cellular processes in the extracellular matrix (ECM). The biological effect of HSGAGs depends on disaccharide content and physiological location within the ECM. HSGAGs are also brought into cells during membrane transcytosis and growth factor signaling while protein bound. We sought to probe the impact of free HSGAGs within the cell by using heparin as a model HSGAG. A library of poly(beta-amino ester)s, which internalize DNA, was examined for the capacity of its members to internalize heparin. Fourteen polymers enabled heparin internalization. The most efficacious polymer reduced murine melanoma cell growth by 73%. No glycosaminoglycan was as efficacious as highly sulfated, full-length heparin. Internalized heparin likely interferes with transcription factor function and subsequently induces apoptotic cell death. Therefore, internalized heparin is a novel mechanism for inducing apoptosis of cancer cells.
Collapse
Affiliation(s)
- David Berry
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | | | | | | |
Collapse
|
30
|
Berry D, Shriver Z, Venkataraman G, Sasisekharan R. Quantitative assessment of FGF regulation by cell surface heparan sulfates. Biochem Biophys Res Commun 2004; 314:994-1000. [PMID: 14751231 DOI: 10.1016/j.bbrc.2003.12.188] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Heparin/heparan sulfate-like glycosaminoglycans (HSGAGs) modulate the activity of the fibroblast growth factor (FGF) family of proteins. Through interactions with both FGFs and FGF receptors (FGFRs), HSGAGs mediate FGF-FGFR binding and oligomerization leading to FGFR phosphorylation and initiation of intracellular signaling cascades. We describe a methodology to examine the impact of heparan sulfate fine structure and source on FGF-mediated signaling. Mitogenic assays using BaF3 cells transfected with specific FGFR isoforms allow for the quantification of FGF1 and FGF2 induced responses independent of conflicting influences. As such, this system enables a systematic investigation into the role of cell surface HSGAGs on FGF signaling. We demonstrate this approach using cell surface-derived HSGAGs and find that distinct HSGAGs elicit differential FGF response patterns through FGFR1c and FGFR3c. We conclude that this assay system can be used to probe the ability of distinct HSGAG species to regulate the activity of specific FGF-FGFR pairs.
Collapse
Affiliation(s)
- David Berry
- Harvard Medical School, Boston, MA 02115, USA
| | | | | | | |
Collapse
|
31
|
Zamfir A, Seidler DG, Kresse H, Peter-Katalinić J. Structural investigation of chondroitin/dermatan sulfate oligosaccharides from human skin fibroblast decorin. Glycobiology 2003; 13:733-42. [PMID: 12799343 DOI: 10.1093/glycob/cwg086] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Hybrid chondroitin/dermatan sulfate (CS/DS) glycosaminoglycan chains, derived from decorin secreted by human skin fibroblasts, were shown to interact with FGF-2, as did oligosaccharides derived therefrom by chondroitin B lyase digestion. In a first attempt to identify the biologically active sequence, a novel protocol for structural analysis of enzyme-resistant oligosaccharides larger than standard trisulfated hexasaccharides was developed. The method bases on capillary electrophoresis (CE) for separating oversulfated species in offline combination with nanoelectrospray ionization quadrupole time-of-flight tandem mass spectrometry (nanoESI-QTOF-MS/MS) in the negative ion mode. Under optimized CE and ESI-MS conditions, up to 12-mer oligosaccharides with different degrees of sulfation were identified. A novel tandem MS protocol (CID-VE) was applied to elucidate the structure of a previously undescribed pentasulfated CS/DS hexasaccharide, Delta-4,5-IdoAGalNAc[GlcAGalNAc]2(5S). In this molecular species, detected as a triply charged ion at m/z 511.38, three sulfates are found in the IdoAGalNAcGlcA moiety offering two structural variants: one containing sulfated IdoA together with a disulfated GalNAc moiety and in the other one both uronic acids, that is, GlcA and IdoA and the amino sugar each carry a sulfate ester group.
Collapse
Affiliation(s)
- Alina Zamfir
- Institute for Medical Physics and Biophysics, Biomedical Analysis Department, University of Münster, Robert-Koch-Str. 31, D-48149, Münster, Germany
| | | | | | | |
Collapse
|
32
|
Berry D, Shriver Z, Natke B, Kwan CP, Venkataraman G, Sasisekharan R. Heparan sulphate glycosaminoglycans derived from endothelial cells and smooth muscle cells differentially modulate fibroblast growth factor-2 biological activity through fibroblast growth factor receptor-1. Biochem J 2003; 373:241-9. [PMID: 12659634 PMCID: PMC1223466 DOI: 10.1042/bj20021760] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2002] [Revised: 03/11/2003] [Accepted: 03/27/2003] [Indexed: 11/17/2022]
Abstract
Fibroblast growth factor (FGF) signalling is involved in a wide range of important biological activities with differential effects in various cell types. The activity of FGF is modulated by heparin/heparan sulphate-like glycosaminoglycans (HSGAGs), found both in the extracellular matrix and on the cell surface. HSGAGs affect FGF signalling by interacting with both the growth factor and the FGF receptor (FGFR). In this study we sought to investigate whether HSGAGs at the cell surface of bovine aortic endothelial cells (BAEC) and smooth muscle cells (SMC) can differentially modulate FGF signalling in these cell types and modulate their differential response to FGF. We find that SMC and BAEC express the same FGFR isoforms and bind FGF2 with equal affinity at the cell surface, yet FGF has a markedly higher proliferative effect on SMC than on BAEC. Isolated HSGAGs from these two cell types were found to elicit distinct patterns of proliferation in chlorate-treated cells. Furthermore, examination of focal sequences reveals that HSGAGs from SMC, but not those from BAEC, retain the sulphation pattern necessary to induce FGF2 activity. As such, the differences in FGF2-mediated proliferation can be explained by the distinct cell surface HSGAGs of the two cell types. We conclude that the focal sequences of cell surface HSGAGs from SMC and BAEC govern, at least in part, the differential activity of FGF2 on these two cell types.
Collapse
MESH Headings
- Animals
- Aorta
- Base Sequence
- Cattle
- Cell Division/drug effects
- Cell Line
- DNA Primers
- Disaccharides/chemistry
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/physiology
- Fibroblast Growth Factor 2/pharmacokinetics
- Fibroblast Growth Factor 2/pharmacology
- Heparitin Sulfate/chemistry
- Heparitin Sulfate/physiology
- Kinetics
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Protein Isoforms/genetics
- Receptor Protein-Tyrosine Kinases/genetics
- Receptor Protein-Tyrosine Kinases/physiology
- Receptor, Fibroblast Growth Factor, Type 1
- Receptors, Fibroblast Growth Factor/genetics
- Receptors, Fibroblast Growth Factor/physiology
- Recombinant Proteins/metabolism
- Recombinant Proteins/pharmacology
- Reverse Transcriptase Polymerase Chain Reaction
Collapse
Affiliation(s)
- David Berry
- Harvard Medical School, 160 Longwood Avenue, Boston, MA 02215, USA
| | | | | | | | | | | |
Collapse
|
33
|
Qiao D, Meyer K, Mundhenke C, Drew SA, Friedl A. Heparan sulfate proteoglycans as regulators of fibroblast growth factor-2 signaling in brain endothelial cells. Specific role for glypican-1 in glioma angiogenesis. J Biol Chem 2003; 278:16045-53. [PMID: 12591930 DOI: 10.1074/jbc.m211259200] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fibroblast growth factor-2 (FGF2) is a potent angiogenic factor in gliomas. Heparan sulfate promotes ligand binding to receptor tyrosine kinase and regulates signaling. The goal of this study was to examine the contribution of heparan sulfate proteoglycans (HSPGs) to glioma angiogenesis. Here we show that all brain endothelial cell HSPGs carry heparan sulfate chains similarly capable of forming a ternary complex with FGF2 and fibroblast growth factor receptor-1c and of promoting a mitogenic signal. Immunohistochemical analysis revealed that glypican-1 was overexpressed in glioma vessel endothelial cells, whereas this cell-surface HSPG was consistently undetectable in normal brain vessels. To determine the effect of increased glypican-1 expression on FGF2 signaling, we transfected normal brain endothelial cells, which express low base-line levels of glypican-1, with this proteoglycan. Glypican-1 expression enhanced growth of brain endothelial cells and sensitized them to FGF2-induced mitogenesis despite the fact that glypican-1 remained a minor proteoglycan. In contrast, overexpression of syndecan-1 had no effect on growth or FGF2 sensitivity. We conclude that the glypican-1 core protein has a specific role in FGF2 signaling. Glypican-1 overexpression may contribute to angiogenesis and the radiation resistance characteristic of this malignancy.
Collapse
Affiliation(s)
- Dianhua Qiao
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Clinical Sciences Center K4/850, Madison, WI 53562-8550, USA
| | | | | | | | | |
Collapse
|
34
|
Facchiano A, Russo K, Facchiano AM, De Marchis F, Facchiano F, Ribatti D, Aguzzi MS, Capogrossi MC. Identification of a novel domain of fibroblast growth factor 2 controlling its angiogenic properties. J Biol Chem 2003; 278:8751-60. [PMID: 12496262 DOI: 10.1074/jbc.m209936200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fibroblast growth factor 2 (FGF-2) is a potent factor modulating the activity of many cell types. Its dimerization and binding to high affinity receptors are considered to be necessary steps to induce FGF receptor phosphorylation and signaling activation. A structural analysis was carried out and a region encompassing residues 48-58 of human FGF-2 was identified, as potentially involved in FGF-2 dimerization. A peptide (FREG-48-58) derived from this region strongly and specifically inhibited FGF-2 induced proliferation and migration of primary bovine aorta endothelial cells (BAEC) in vitro, and markedly reduced FGF-2-dependent angiogenesis in two distinct in vivo assays. To further investigate the role of region 48-58, a polyclonal antibody raised against FREG-(48-58) was tested and was found to block FGF-2 action in vitro. Human FGF-2 has three histidine residues, one falling within the region 48-58. Chemical modification of histidine residues blocked FGF-2 activity and FREG-(48-58) inhibitory effect in vitro, indicating that histidine residues, in particular the one within FREG-(48-58) region, play a crucial role in the observed activity. Additional experiments showed that FREG-(48-58) specifically interacted with FGF-2, impaired FGF-2-interaction with itself, with heparin and with FGF receptor 1, and inhibited FGF-2-induced receptor phosphorylation and FGF-2 internalization. These data indicate for the first time that region 48-58 of FGF-2 is a functional domain controlling FGF-2 activity.
Collapse
Affiliation(s)
- Antonio Facchiano
- Laboratorio Patologia Vascolare, Istituto Dermopatico dell'Immacolata, IRCCS, 00167 Roma, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Collin-Osdoby P, Rothe L, Bekker S, Anderson F, Huang Y, Osdoby P. Basic fibroblast growth factor stimulates osteoclast recruitment, development, and bone pit resorption in association with angiogenesis in vivo on the chick chorioallantoic membrane and activates isolated avian osteoclast resorption in vitro. J Bone Miner Res 2002; 17:1859-71. [PMID: 12369790 DOI: 10.1359/jbmr.2002.17.10.1859] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Increased local osteoclast (OC)-mediated bone resorption coincides with angiogenesis in normal bone development and fracture repair, as well as in pathological disorders such as tumor-associated osteolysis and inflammatory-related rheumatoid arthritis or periodontal disease. Angiogenic stimulation causes recruitment, activation, adhesion, transmigration, and differentiation of hematopoietic cells which may therefore enable greater numbers of pre-OC to emigrate from the circulation and develop into bone-resorptive OCs. A chick chorioallantoic membrane (CAM) model, involving coimplantation of a stimulus in an agarose plug directly adjacent to a bone chip was used to investigate if a potent angiogenic stimulator, basic fibroblast growth factor (bFGF), could promote OC recruitment, differentiation, and resorption in vivo. Angiogenesis elicited by bFGF on the CAM was accompanied by increased OC formation and bone pit resorption (both overall and on a per OC basis) on the bone implants in vivo. In complementary in vitro assays, bFGF did not directly stimulate avian OC development from bone marrow mononuclear cell precursors, consistent with their low mRNA expression of the four avian signaling FGF receptors (FGFR)-1, FGFR-2, FGFR-3, and FGFR-like embryonic kinase (FREK). In contrast, bFGF activated isolated avian OC bone pit resorption via mechanisms inhibited by a selective cyclo-oxygenase (COX)-2 prostaglandin inhibitor (NS-398) or p42/p44 MAPK activation inhibitor (PD98059), consistent with a relatively high expression of FGFR-1 by differentiated avian OCs. Thus, bFGF may sensitively regulate local bone resorption and remodeling through direct and indirect mechanisms that promote angiogenesis and OC recruitment, formation, differentiation, and activated bone pit resorption. The potential for bFGF to coinduce angiogenesis and OC bone remodeling may find clinical applications in reconstructive surgery, fracture repair, or the treatment of avascular necrosis. Alternatively, inhibiting such bFGF-dependent processes may aid in the treatment of inflammatory-related or metastatic bone loss.
Collapse
|
36
|
Iozzo RV, San Antonio JD. Heparan sulfate proteoglycans: heavy hitters in the angiogenesis arena. J Clin Invest 2001. [DOI: 10.1172/jci200113738] [Citation(s) in RCA: 336] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
37
|
Iozzo RV, San Antonio JD. Heparan sulfate proteoglycans: heavy hitters in the angiogenesis arena. J Clin Invest 2001; 108:349-55. [PMID: 11489925 PMCID: PMC209371 DOI: 10.1172/jci13738] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Affiliation(s)
- R V Iozzo
- Department of Pathology, Anatomy and Cell Biology, Cellular Biology and Signaling Program, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
| | | |
Collapse
|
38
|
Kwan CP, Venkataraman G, Shriver Z, Raman R, Liu D, Qi Y, Varticovski L, Sasisekharan R. Probing fibroblast growth factor dimerization and role of heparin-like glycosaminoglycans in modulating dimerization and signaling. J Biol Chem 2001; 276:23421-9. [PMID: 11292822 DOI: 10.1074/jbc.m010786200] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
For a number of growth factors and cytokines, ligand dimerization is believed to be central to the formation of an active signaling complex. In the case of fibroblast growth factor-2 (FGF2) signaling, heparin/heparan sulfate-like glycosaminoglycans (HLGAGs) are involved through interaction with both FGF2 and its receptors (FGFRs) in assembling a tertiary complex and modulating FGF2 activity. Biochemical data have suggested different modes of HLGAG-induced FGF2 dimerization involving specific protein-protein contacts. In addition, several recent x-ray crystallography studies of FGF.FGFR and FGF.FGFR.HLGAG complexes have revealed other modes of molecular assemblage, with no FGF-FGF contacts. All these different biochemical and structural findings have clarified less and in fact raised more questions as to which mode of FGF2 dimerization, if any, is essential for signaling. In this study, we address the issue of FGF2 dimerization in signaling using a combination of biochemical, biophysical, and site-directed mutagenesis approaches. Our findings presented here provide direct evidence of FGF2 dimerization in mediating FGF2 signaling.
Collapse
Affiliation(s)
- C P Kwan
- Division of Bioengineering and Environmental Health, the Harvard-Massachusetts Institute of Technology Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Berry D, Kwan CP, Shriver Z, Venkataraman G, Sasisekharan R. Distinct heparan sulfate glycosaminoglycans are responsible for mediating fibroblast growth factor-2 biological activity through different fibroblast growth factor receptors. FASEB J 2001; 15:1422-4. [PMID: 11387244 DOI: 10.1096/fj.00-0661fje] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- D Berry
- Division of Bioengineering and Environmental Health, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | | | | | | |
Collapse
|
40
|
Cailliau K, Browaeys-Poly E, Vilain JP. Fibroblast growth factors 1 and 2 differently activate MAP kinase in Xenopus oocytes expressing fibroblast growth factor receptors 1 and 4. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1538:228-33. [PMID: 11336793 DOI: 10.1016/s0167-4889(01)00074-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The mitogen-activated protein kinase (MAP kinase) signalling cascade activated by fibroblast growth factors (FGF1 and FGF2) was analysed in a model system, Xenopus oocytes, expressing fibroblast growth factor receptors (FGFR1 and FGFR4). Stimulation of FGFR1 by FGF1 or FGF2 and FGFR4 by FGF1 induced a sustained phosphorylation of extracellular signal-regulated protein kinase 2 (ERK2) and meiosis reinitiation. In contrast, FGFR4 stimulation by FGF2 induced an early transient activation of ERK2 and no meiosis reinitiation. FGFR4 transduction cascades were differently activated by FGF1 and FGF2. Early phosphorylation of ERK2 was blocked by the dominant negative form of growth factor-bound protein 2 (Grb2) and Ras, for FGF1-FGFR4 and FGF2-FGFR4. The phosphatidylinositol 3-kinase (PI3 kinase) inhibitors wortmannin and LY294002 only prevented the early ERK2 phosphorylation triggered by FGF2-FGFR4 but not by FGF1-FGFR4. ERK2 phosphorylation triggered by FGFR4 depended on the Grb2/Ras pathway and also involved PI3 kinase in a time-dependent manner.
Collapse
Affiliation(s)
- K Cailliau
- Université des Sciences et Technologies de Lille, Laboratoire de Biologie du Développement, UE 1033, Bâtiment SN3, 59655 Cedex, Villeneuve D'Ascq, France
| | | | | |
Collapse
|
41
|
Bush MA, Samara E, Whitehouse MJ, Yoshizawa C, Novicki DL, Pike M, Laham RJ, Simons M, Chronos NA. Pharmacokinetics and pharmacodynamics of recombinant FGF-2 in a phase I trial in coronary artery disease. J Clin Pharmacol 2001; 41:378-85. [PMID: 11304894 DOI: 10.1177/00912700122010230] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fibroblast growth factor-2 (FGF-2) is a heparin-binding protein capable of inducing angiogenesis in multiple animal models of chronic ischemia. The pharmacokinetics and pharmacodynamics of a single dose of recombinant FGF-2 (rFGF-2) administered by intracoronary or intravenous infusion were evaluated in a Phase I trial in 66 patients with severe coronary artery disease. rFGF-2 displayed biphasic elimination with a mean studywide distribution t1/2 of 21 minutes and a mean apparent terminal elimination t1/2 of 7.6 hours. Systemic exposure to rFGF-2 was comparable following intracoronary or intravenous administration. Peak plasma concentration and area under the concentration-time curve increased proportionally with dose, indicating linear pharmacokinetics over the dose range examined (0.33 to 48.0 micrograms/kg). Greater systemic exposure was observed when heparin was administered closer to rFGF-2 infusion, consistent with slower clearance of heparin/rFGF-2 complexes. Infusion of rFGF-2 was associated with changes in acute hemodynamics. While a clear PK/PD dose-response relationship was not established, a trend toward hypotension and tachycardia with higher rFGF-2 doses was observed.
Collapse
Affiliation(s)
- M A Bush
- Chiron Corporation, 4560 Horton Street M/S 4. 178, Emeryville, CA 94608-2916, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Keiser N, Venkataraman G, Shriver Z, Sasisekharan R. Direct isolation and sequencing of specific protein-binding glycosaminoglycans. Nat Med 2001; 7:123-8. [PMID: 11135627 DOI: 10.1038/83263] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- N Keiser
- Division of Bioengineering & Environmental Health, Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | | | | |
Collapse
|