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Paoletti F. ATP binding to Nerve Growth Factor (NGF) and pro-Nerve Growth Factor (proNGF): an endogenous molecular switch modulating neurotrophins activity. Biochem Soc Trans 2024; 52:1293-1304. [PMID: 38716884 DOI: 10.1042/bst20231089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/19/2024] [Accepted: 04/22/2024] [Indexed: 06/27/2024]
Abstract
ATP has recently been reconsidered as a molecule with functional properties which go beyond its recognized role of the energetic driver of the cell. ATP has been described as an allosteric modulator as well as a biological hydrotrope with anti-aggregation properties in the crowded cellular environment. The role of ATP as a modulator of the homeostasis of the neurotrophins (NTs), a growth factor protein family whose most known member is the nerve growth factor (NGF), has been investigated. The modulation of NTs by small endogenous ligands is still a scarcely described area, with few papers reporting on the topic, and very few reports on the molecular determinants of these interactions. However, a detailed atomistic description of the NTs interaction landscape is of urgent need, aiming at the identification of novel molecules as potential therapeutics and considering the wide range of potential pharmacological applications for NGF and its family members. This mini-review will focus on the unique cartography casting the interactions of the endogenous ligand ATP, in the interaction with NGF as well as with its precursor proNGF. These interactions revealed interesting features of the ATP binding and distinct differences in the binding mode between the highly structured mature NGF and its precursor, proNGF, which is characterized by an intrinsically unstructured domain. The overview on the recent available data will be presented, together with the future perspectives on the field.
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Affiliation(s)
- Francesca Paoletti
- Institute of Crystallography - C.N.R. - Trieste Outstation, Area Science Park - Basovizza, S.S.14 - Km. 163.5, I-34149 Trieste, Italy
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Paoletti F, Covaceuszach S, Cassetta A, Calabrese AN, Novak U, Konarev P, Grdadolnik J, Lamba D, Golič Grdadolnik S. Distinct conformational changes occur within the intrinsically unstructured pro-domain of pro-Nerve Growth Factor in the presence of ATP and Mg 2. Protein Sci 2023; 32:e4563. [PMID: 36605018 PMCID: PMC9878617 DOI: 10.1002/pro.4563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/24/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023]
Abstract
Nerve growth factor (NGF), the prototypical neurotrophic factor, is involved in the maintenance and growth of specific neuronal populations, whereas its precursor, proNGF, is involved in neuronal apoptosis. Binding of NGF or proNGF to TrkA, p75NTR , and VP10p receptors triggers complex intracellular signaling pathways that can be modulated by endogenous small-molecule ligands. Here, we show by isothermal titration calorimetry and NMR that ATP binds to the intrinsically disordered pro-peptide of proNGF with a micromolar dissociation constant. We demonstrate that Mg2+ , known to play a physiological role in neurons, modulates the ATP/proNGF interaction. An integrative structural biophysics analysis by small angle X-ray scattering and hydrogen-deuterium exchange mass spectrometry unveils that ATP binding induces a conformational rearrangement of the flexible pro-peptide domain of proNGF. This suggests that ATP may act as an allosteric modulator of the overall proNGF conformation, whose likely distinct biological activity may ultimately affect its physiological homeostasis.
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Affiliation(s)
- Francesca Paoletti
- Laboratory for Molecular Structural Dynamics, Theory DepartmentNational Institute of ChemistryLjubljanaSlovenia
| | | | - Alberto Cassetta
- Institute of Crystallography—C.N.R.—Trieste OutstationTriesteItaly
| | - Antonio N. Calabrese
- School of Molecular and Cellular Biology, Astbury Centre for Structural Molecular BiologyUniversity of LeedsLeedsUK
| | - Urban Novak
- Laboratory for Molecular Structural Dynamics, Theory DepartmentNational Institute of ChemistryLjubljanaSlovenia
| | - Petr Konarev
- A.V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics”Russian Academy of SciencesMoscowRussia
| | - Jože Grdadolnik
- Laboratory for Molecular Structural Dynamics, Theory DepartmentNational Institute of ChemistryLjubljanaSlovenia
| | - Doriano Lamba
- Institute of Crystallography—C.N.R.—Trieste OutstationTriesteItaly
- Interuniversity Consortium “Biostructures and Biosystems National Institute”RomeItaly
| | - Simona Golič Grdadolnik
- Laboratory for Molecular Structural Dynamics, Theory DepartmentNational Institute of ChemistryLjubljanaSlovenia
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Paoletti F, Lamba D. Small Endogenous Ligands Modulation of Nerve Growth Factor Bioactivity: A Structural Biology Overview. Cells 2021; 10:cells10123462. [PMID: 34943971 PMCID: PMC8700322 DOI: 10.3390/cells10123462] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/01/2021] [Accepted: 12/03/2021] [Indexed: 01/12/2023] Open
Abstract
Experiments with cell cultures and animal models have provided solid support for the assumption that Nerve Growth Factor (NGF) plays a key role in the regulation of neuronal cell survival and death. Recently, endogenous ligands have been proposed as physiological modulators of NGF biological activity as part of this regulatory cascade. However, the structural and mechanistic determinants for NGF bioactivity remain to be elucidated. We recently unveiled, by an integrated structural biology approach, the ATP binding sites of NGF and investigated the effects on TrkA and p75NTR receptors binding. These results pinpoint ATP as a genuine endogenous modulator of NGF signaling, paving the way to the characterization of not-yet-identified chemical diverse endogenous biological active small molecules as novel modulators of NGF. The present review aims at providing an overview of the currently available 3D structures of NGF in complex with different small endogenous ligands, featuring the molecular footprints of the small molecules binding. This knowledge is essential for further understanding the functional role of small endogenous ligands in the modulation of neurotrophins signaling in physiological and pathological conditions and for better exploiting the therapeutic potentialities of NGF.
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Affiliation(s)
- Francesca Paoletti
- Laboratory for Molecular Structural Dynamics, Theory Department, National Institute of Chemistry, SI-1001 Ljubljana, Slovenia
- Correspondence:
| | - Doriano Lamba
- Institute of Crystallography—C.N.R.—Trieste Outstation, Area Science Park—Basovizza, I-34149 Trieste, Italy;
- Interuniversity Consortium “Biostructures and Biosystems National Institute”, I-00136 Roma, Italy
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Paoletti F, Merzel F, Cassetta A, Ogris I, Covaceuszach S, Grdadolnik J, Lamba D, Golič Grdadolnik S. Endogenous modulators of neurotrophin signaling: Landscape of the transient ATP-NGF interactions. Comput Struct Biotechnol J 2021; 19:2938-2949. [PMID: 34136093 PMCID: PMC8164016 DOI: 10.1016/j.csbj.2021.05.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 04/29/2021] [Accepted: 05/02/2021] [Indexed: 12/02/2022] Open
Abstract
High-resolution solution NMR structure of rhNGF has been determined. Quinary interactions characterize ATP binding to rhNGF. SPR, ITC and STD-NMR reveal ATP binding to rhNGF with mM affinity. NMR and MD analysis pinpoint to the presence of two binding sites of ATP on rhNGF. Stoichiometry of ATP-Mg2+ or Zn2+-rhNGF mixtures affects KD affinity to TrkA/p75NTR.
The Nerve Growth Factor (NGF) neurotrophin acts in the maintenance and growth of neuronal populations. Despite the detailed knowledge of NGF’s role in neuron physiology, the structural and mechanistic determinants of NGF bioactivity modulated by essential endogenous ligands are still lacking. We present the results of an integrated structural and advanced computational approach to characterize the extracellular ATP-NGF interaction. We mapped by NMR the interacting surface and ATP orientation on NGF and revealed the functional role of this interaction in the binding to TrkA and p75NTR receptors by SPR. The role of divalent ions was explored in conjunction with ATP. Our results pinpoint ATP as a likely transient molecular modulator of NGF signaling, in health and disease states.
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Key Words
- ARIA, Ambiguous Restraints for Iterative Assignment
- ATP modulation
- BDNF, Brain Derived Neurotrophic Factor
- CARA, Computer Aided Resonance Assignment
- CS-E, Chrondroitin Sulfate E
- CSP, Chemical Shift Perturbation
- DSF, Differential Scanning Fluorimetry
- EI-MS, Electron Ionization Mass Spectrometry
- Endogenous ligands
- FGF2, Fibroblast Growth Factor 2
- FT-IR, Fourier Transform Infrared Spectroscopy
- HBD, Heparin Binding Domain
- HSQC, Heteronuclear Single Quantum Coherence
- ITC, Isothermal Titration Calorimetry
- MALDI-TOF MS, Matrix Assisted Laser Desorption Ionization-Time Of Flight Mass Spectrometry
- MD, Molecular Dynamics
- MS, Mass Spectrometry
- NGF interactions
- NGF, Nerve Growth Factor
- NMR, Nuclear Magnetic Resonance
- NOE, Nuclear Overhouser Effect
- NOESY, Nuclear Overhauser Effect Spectroscopy
- NT, NeuroTrophin
- Neurotrophins
- P20, Polysorbate 20
- PME, Particle Mesh Ewald
- RMSD, Root Mean Square Deviation
- SAR, Structure-Activity Relationship
- SPR, Surface Plasmon Resonance
- STD, Saturation-Transfer Difference
- TrkA, Tyrosine Kinase Receptor A
- TrkA, p75NTR receptors
- p75NTR, p75 NeuroTrophin Receptor
- proNGF, proNGF – NGF precursor
- rh-proNGF, recombinant human proNGF – NGF precursor
- rhNGF, recombinant human NGF
- rmNGF, recombinant mouse NGF
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Affiliation(s)
- Francesca Paoletti
- Laboratory for Molecular Structural Dynamics, Theory Department, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia
| | - Franci Merzel
- Laboratory for Molecular Structural Dynamics, Theory Department, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia
| | - Alberto Cassetta
- Institute of Crystallography - C.N.R.- Trieste Outstation. Area Science Park - Basovizza, S.S.14 - Km. 163.5, I-34149 Trieste, Italy
| | - Iza Ogris
- Laboratory for Molecular Structural Dynamics, Theory Department, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia
| | - Sonia Covaceuszach
- Institute of Crystallography - C.N.R.- Trieste Outstation. Area Science Park - Basovizza, S.S.14 - Km. 163.5, I-34149 Trieste, Italy
| | - Jože Grdadolnik
- Laboratory for Molecular Structural Dynamics, Theory Department, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia
| | - Doriano Lamba
- Institute of Crystallography - C.N.R.- Trieste Outstation. Area Science Park - Basovizza, S.S.14 - Km. 163.5, I-34149 Trieste, Italy.,Interuniversity Consortium "Biostructures and Biosystems National Institute", Viale delle Medaglie d'Oro 305, I-00136 Roma, Italy
| | - Simona Golič Grdadolnik
- Laboratory for Molecular Structural Dynamics, Theory Department, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia
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Zhang K, Huang D, Yan Z, Wang C. Heparin/collagen encapsulating nerve growth factor multilayers coated aligned PLLA nanofibrous scaffolds for nerve tissue engineering. J Biomed Mater Res A 2017; 105:1900-1910. [PMID: 28256802 DOI: 10.1002/jbm.a.36053] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 02/19/2017] [Accepted: 02/27/2017] [Indexed: 11/06/2022]
Abstract
Biomimicing topological structure of natural nerve tissue to direct axon growth and controlling sustained release of moderate neurotrophic factors are extremely propitious to the functional recovery of damaged nervous systems. In this study, the heparin/collagen encapsulating nerve growth factor (NGF) multilayers were coated onto the aligned poly-L-lactide (PLLA) nanofibrous scaffolds via a layer-by-layer (LbL) self-assembly technique to combine biomolecular signals, and physical guidance cues for peripheral nerve regeneration. Scanning electronic microscopy (SEM) revealed that the surface of aligned PLLA nanofibrous scaffolds coated with heparin/collagen multilayers became rougher and appeared some net-like filaments and protuberances in comparison with PLLA nanofibrous scaffolds. The heparin/collagen multilayers did not destroy the alignment of nanofibers. X-ray photoelectron spectroscopy and water contact angles displayed that heparin and collagen were successfully coated onto the aligned PLLA nanofibrous scaffolds and improved its hydrophilicity. Three-dimensional (3 D) confocal microscopy images further demonstrated that collagen, heparin, and NGF were not only coated onto the surface of aligned PLLA nanofibrous scaffolds but also permeated into the inner of scaffolds. Moreover, NGF presented a sustained release for 2 weeks from aligned nanofibrous scaffolds coated with 5.5 bilayers or above and remained good bioactivity. The heparin/collagen encapsulating NGF multilayers coated aligned nanofibrous scaffolds, in particular 5.5 bilayers or above, was more beneficial to Schwann cells (SCs) proliferation and PC12 cells differentiation as well as the SC cytoskeleton and neurite growth along the direction of nanofibrous alignment compared to the aligned PLLA nanofibrous scaffolds. This novel scaffolds combining sustained release of bioactive NGF and aligned nanofibrous topography presented an excellent potential in peripheral nerve regeneration. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1900-1910, 2017.
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Affiliation(s)
- Kuihua Zhang
- College of Materials and Textile Engineering, Jiaxing University, Jiaxing, 314001, China
| | - Dianwu Huang
- College of Civil Engineering and Architecture, Jiaxing University, Jiaxing, 314001, China
| | - Zhiyong Yan
- College of Materials and Textile Engineering, Jiaxing University, Jiaxing, 314001, China
| | - Chunyang Wang
- Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
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Nerve growth factor and brain-derived neurotrophic factor but not granulocyte colony-stimulating factor, nimodipine and dizocilpine, require ATP for neuroprotective activity after oxygen-glucose deprivation of primary neurons. Brain Res 2012; 1448:20-6. [PMID: 22386494 DOI: 10.1016/j.brainres.2012.02.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 01/31/2012] [Accepted: 02/07/2012] [Indexed: 11/21/2022]
Abstract
In previous work, we have demonstrated by radiolabeling, mass spectrometry and site-directed mutagenesis that nerve growth factor (NGF) as well as brain-derived neurotrophic factor (BDNF) and fibroblast growth factor 2 (FGF2) are capable of ATP-binding and that this binding appears to be essential for their neuroprotective activity. In this study, we attempted to shed some light on the question whether ATP is a general prerequisite for neuroprotection. Therefore, we used the non-ATP-binding granulocyte colony-stimulating factor (GCSF), the calcium antagonist nimodipine and the NMDA antagonist dizocilpine to find out whether they need ATP for neuroprotection comparable to NGF and BDNF. However, ATP was not necessary for the neuroprotective effects of GCSF, nimodipine and dizocilpine on primary cultures of rat cortical neurons damaged by oxygen-glucose deprivation whereas neuroprotection was demonstrable for NGF and BDNF only when ATP was present in the culture medium at a concentration higher than ca. 0.4nmol/l. In circular dichroism studies ATP caused changes of the secondary structure of NGF but not of GCSF. Taken together, we suggest that ATP is not a general prerequisite for neuroprotectivity but some growth factors like NGF and BDNF can stimulate their receptors only if they have bound ATP.
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Ferenz KB, Rose K, König S, Krieglstein J. ATP-NGF-complex, but not NGF, is the neuroprotective ligand. Neurochem Int 2011; 59:989-95. [PMID: 21930174 DOI: 10.1016/j.neuint.2011.08.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 08/25/2011] [Accepted: 08/26/2011] [Indexed: 12/12/2022]
Abstract
We have shown previously that nerve growth factor (NGF) requires only low nanomolar ATP concentrations in the cell culture medium to protect cortical rat neurons (CRN) from cellular damage induced by staurosporine (STS). We have also demonstrated before that NGF and other growth factors form stable non-covalent complexes with ATP. Here we demonstrated that 8N(1)ATP-NGF, but not NGF, protected CRN against damage. The photo-reactive ATP derivative 8N(3)ATP was incubated with NGF and was trapped in its position by UV irradiation forming a covalent bond. The cross-link with a molar ratio of 1:1 (8N(1)ATP:NGF) was confirmed by mass spectrometry. Circular dichroism experiments revealed that 8N(1)ATP altered the secondary structure of NGF in the same way as ATP did. Covalently bound 8N(1)ATP-NGF was shown to be stable in the presence of the ATP-hydrolyzing enzyme alkaline phosphatase while the non-covalent ATP-NGF-complex dissociated with the removal of free ATP from the solution. 8N(1)ATP-NGF protected CRN against damage by STS independently of free ATP in the culture medium. These results suggest that the ATP-NGF-complex, but not NGF, is the active ligand.
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Affiliation(s)
- Katja Bettina Ferenz
- Institut für Pharmazeutische und Medizinische Chemie, Fachbereich Chemie und Pharmazie, Germany
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Gast RE, König S, Rose K, Ferenz KB, Krieglstein J. Binding of ATP to vascular endothelial growth factor isoform VEGF-A165 is essential for inducing proliferation of human umbilical vein endothelial cells. BMC BIOCHEMISTRY 2011; 12:28. [PMID: 21619628 PMCID: PMC3125245 DOI: 10.1186/1471-2091-12-28] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Accepted: 05/27/2011] [Indexed: 01/10/2023]
Abstract
BACKGROUND ATP binding is essential for the bioactivity of several growth factors including nerve growth factor, fibroblast growth factor-2 and brain-derived neurotrophic factor. Vascular endothelial growth factor isoform 165 (VEGF-A(165)) induces the proliferation of human umbilical vein endothelial cells, however a dependence on ATP-binding is currently unknown. The aim of the present study was to determine if ATP binding is essential for the bioactivity of VEGF-A(165). RESULTS We found evidence that ATP binding to VEGF-A(165) induced a conformational change in the secondary structure of the growth factor. This binding appears to be significant at the biological level, as we found evidence that nanomolar levels of ATP (4-8 nm) are required for the VEGF-A(165)-induced proliferation of human umbilical vein endothelial cells. At these levels, purinergic signaling by ATP via P2 receptors can be excluded. Addition of alkaline phosphate to cell culture lowered the ATP concentration in the cell culture medium to 1.8 nM and inhibited cell proliferation. CONCLUSIONS We propose that proliferation of endothelial cells is induced by a VEGF-A(165)-ATP complex, rather than VEGF-A(165) alone.
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Affiliation(s)
- Ronald E Gast
- Institut für Pharmazeutische und Medizinische Chemie, Hittorfstrasse 58-62, 48149 Münster, Germany
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Interaction of ATP with fibroblast growth factor 2: biochemical characterization and consequence for growth factor stability. BMC BIOCHEMISTRY 2011; 12:14. [PMID: 21447157 PMCID: PMC3072325 DOI: 10.1186/1471-2091-12-14] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Accepted: 03/29/2011] [Indexed: 11/30/2022]
Abstract
Background Fibroblast growth factor 2, a well-characterized heparin-binding growth factor, is involved in many biological processes like embryogenesis, cell proliferation and angiogenesis. However, this growth factor is very unstable and shows rapid degradation in aqueous solution. Beside the well-known stabilization of FGF2 by heparin or heparan sulphate, the recently discovered binding to ATP also shows a stabilizing and protective effect on this growth factor. Results Here we determined the dissociation constant of ATP on FGF2 by equilibrium microdialysis (KD: 59.8 μM) and analyzed the impact of this binding on secondary structure by CD-spectroscopy. ATP-binding to FGF2 significantly changed the secondary structure of this growth factor with a shift to random coil structure elements. We also analyzed the influence of this binding on the stability of FGF2 in aqueous solution over a period of 2 h. While the amount of untreated FGF2 is reduced drastically over this period of time, ATP-binding reduces the degradation considerably. Conclusions Taken together, our data suggest an important role of ATP in FGF2-stabilization beside the well known-role of heparin and heparan sulphate.
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Interaction of clodronate with fibroblast growth factor 2 reduces FGF2-activity in endothelial cells. Biomed Pharmacother 2010; 65:46-51. [PMID: 21177067 DOI: 10.1016/j.biopha.2010.10.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Accepted: 10/12/2010] [Indexed: 11/24/2022] Open
Abstract
Stabilization of fibroblast growth factors from heat denaturation and proteolytic digestion by bound heparin and heparan sulphate proteoglycans is known for more than 20 years. Furthermore, ATP-binding to FGF2 also leads to stabilization of this growth factor as discovered recently. The physiological importance of this protection is not yet clear but has become the focal point of interest. In this study we used the method of stabilizing FGF2 from proteolytic degradation to identify some bisphosphonates, namely clodronate and etidronate, which interact with FGF2. These two bisphoshonates protect FGF2 from tryptic digestion in vitro. The circular dichroism spectrum of FGF2 incubated with clodronate was significantly shifted compared to the spectrum of non-treated FGF2 indicating a conformational change of the protein after clodronate-binding. Additionally, clodronate and etidronate at low μM concentrations induce a concentration-dependent reduction of FGF2-induced cell proliferation of human umbilical vein endothelial cells. In contrast, proliferation of these cells after addition of clodronate and etidronate without FGF2 was not influenced by these bisphosphonates. Furthermore, the intracellular signaling via ERK1/2 and AKT was inhibited by clodronate and the tube formation, indicating the beginning process of angiogenesis, was reduced. Our results show for the first time that bisphosphonates I) interact with FGF2, II) reduce FGF2-activity and III) decrease the angiogenic potential of this growth factor.
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