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Krishna Saxena,
Ulrich Schieborr,
Oliver Anderka,
Elke Duchardt-Ferner,
Bettina Elshorst,
Santosh Lakshmi Gande,
Julia Janzon,
Denis Kudlinzki,
Sridhar Sreeramulu,
Matthias K Dreyer,
K Ulrich Wendt,
Corentin Herbert, Philippe Duchaussoy,
Marc Bianciotto,
Pierre-Alexandre Driguez,
Gilbert Lassalle,
Pierre Savi,
Moosa Mohammadi,
Françoise Bono,
Harald Schwalbe
[show abstract]
[hide abstract]
ABSTRACT: Fibroblast growth factor (FGF) signaling regulates mammalian development and metabolism, and its dysregulation is implicated in many inherited and acquired diseases, including cancer. Heparan sulfate glycosaminoglycans (HSGAGs) are essential for FGF signaling as they promote FGF.FGF receptor (FGFR) binding and dimerization. Using novel organic synthesis protocols to prepare homogeneously sulfated heparin mimetics (HM), including hexasaccharide (HM(6)), octasaccharide (HM(8)), and decasaccharide (HM(10)), we tested the ability of these HM to support FGF1 and FGF2 signaling through FGFR4. Biological assays show that both HM(8) and HM(10) are significantly more potent than HM(6) in promoting FGF2-mediated FGFR4 signaling. In contrast, all three HM have comparable activity in promoting FGF1.FGFR4 signaling. To understand the molecular basis for these differential activities in FGF1/2.FGFR4 signaling, we used NMR spectroscopy, isothermal titration calorimetry, and size-exclusion chromatography to characterize binding interactions of FGF1/2 with the isolated Ig-domain 2 (D2) of FGFR4 in the presence of HM, and binary interactions of FGFs and D2 with HM. Our data confirm the existence of both a secondary FGF1.FGFR4 interaction site and a direct FGFR4.FGFR4 interaction site thus supporting the formation of the symmetric mode of FGF.FGFR dimerization in solution. Moreover, our results show that the observed higher activity of HM(8) relative to HM(6) in stimulating FGF2.FGFR4 signaling correlates with the higher affinity of HM(8) to bind and dimerize FGF2. Notably FGF2.HM(8) exhibits pronounced positive binding cooperativity. Based on our findings we propose a refined symmetric FGF.FGFR dimerization model, which incorporates the differential ability of HM to dimerize FGFs.
Journal of Biological Chemistry 08/2010; 285(34):26628-40. · 4.77 Impact Factor
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Krishna Saxena,
Ulrich Schieborr,
Oliver Anderka,
Elke Duchardt-Ferner,
Bettina Elshorst,
Santosh Lakshmi Gande,
Julia Janzon,
Denis Kudlinzki,
Sridhar Sreeramulu,
Matthias K. Dreyer,
K. Ulrich Wendt,
Corentin Herbert, Philippe Duchaussoy,
Marc Bianciotto,
Pierre-Alexandre Driguez,
Gilbert Lassalle,
Pierre Savi,
Moosa Mohammadi,
Françoise Bono,
Harald Schwalbe
[show abstract]
[hide abstract]
ABSTRACT: Fibroblast growth factor (FGF) signaling regulates mammalian development and metabolism, and its dysregulation is implicated
in many inherited and acquired diseases, including cancer. Heparan sulfate glycosaminoglycans (HSGAGs) are essential for FGF
signaling as they promote FGF·FGF receptor (FGFR) binding and dimerization. Using novel organic synthesis protocols to prepare
homogeneously sulfated heparin mimetics (HM), including hexasaccharide (HM6), octasaccharide (HM8), and decasaccharide (HM10), we tested the ability of these HM to support FGF1 and FGF2 signaling through FGFR4. Biological assays show that both HM8 and HM10 are significantly more potent than HM6 in promoting FGF2-mediated FGFR4 signaling. In contrast, all three HM have comparable activity in promoting FGF1·FGFR4 signaling.
To understand the molecular basis for these differential activities in FGF1/2·FGFR4 signaling, we used NMR spectroscopy, isothermal
titration calorimetry, and size-exclusion chromatography to characterize binding interactions of FGF1/2 with the isolated
Ig-domain 2 (D2) of FGFR4 in the presence of HM, and binary interactions of FGFs and D2 with HM. Our data confirm the existence
of both a secondary FGF1·FGFR4 interaction site and a direct FGFR4·FGFR4 interaction site thus supporting the formation of
the symmetric mode of FGF·FGFR dimerization in solution. Moreover, our results show that the observed higher activity of HM8 relative to HM6 in stimulating FGF2·FGFR4 signaling correlates with the higher affinity of HM8 to bind and dimerize FGF2. Notably FGF2·HM8 exhibits pronounced positive binding cooperativity. Based on our findings we propose a refined symmetric FGF·FGFR dimerization
model, which incorporates the differential ability of HM to dimerize FGFs.
Journal of Biological Chemistry 08/2010; 285(34):26628-26640. · 4.77 Impact Factor
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Maurice Petitou, Philippe Duchaussoy,
Jean-Marc Herbert,
Gérald Duc,
Mohamed El Hajji,
Jean-François Branellec,
François Donat,
José Necciari,
Roger Cariou,
Jean Bouthier,
Eric Garrigou
[show abstract]
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ABSTRACT: Fondaparinux (Arixtra), a synthetic pentasaccharide, is the first in a new class of antithrombotic agents that selectively inhibit coagulation factor Xa. In vitro experiments demonstrated that it is a selective inhibitor of factor Xa. In plasma, fondaparinux selectively binds to antithrombin, catalyzes factor Xa inhibition, and thereby inhibits thrombin generation. Its antithrombotic efficacy has been demonstrated in various animal models mimicking venous and arterial thrombosis. In humans, its pharmacokinetic profile is favorable, with a rapid onset of antithrombotic activity and an elimination half-life allowing a convenient once-daily dosing regimen. In several clinical trials, fondaparinux was more effective than the reference drug, enoxaparin, in preventing venous thromboembolism after hip fracture, major knee, and elective hip replacement surgeries. The overall reduction in the risk of venous thromboembolism ranged between 26.3 and 56.4%, depending on the trial. This superior efficacy was achieved without increasing the risk of clinically relevant bleeding. Fondaparinux also showed promising results in the treatment of patients with venous thromboembolism and acute coronary syndromes. Thus, it is now established that selective factor Xa inhibition is an efficient way to prevent venous thrombosis. The advent of fondaparinux offers an opportunity to improve substantially the management of venous thromboembolism.
Seminars in Thrombosis and Hemostasis 09/2002; 28(4):393-402. · 4.52 Impact Factor
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ABSTRACT: The cover picture shows how thrombosis occurs in the deep veins of the lower limbs. Stasis, which results from slow and turbulent blood flow, combined with hypercoagulation, caused, for example, by a surgical procedure, may result in thrombus formation. The synthetic sulfated pentasaccharide shown in part is a potent antithrombotic compound that exerts its effect by activation of the plasma protein antithrombin III. Conformationally locked monosaccharides have now been synthesized to demonstrate that L-iduronic acid, one part of the pentasaccharide, must adopt an unusual distorted conformation to activate antithrombin III. Such conformational effects might be relevant in explaining the unique biological properties of glycosaminoglycans that contain L-iduronic acid. In the background of the picture, a flight of vampire bats is attracted by the pentasaccharide. Vampire was the name given to South American blood-sucking bats (Latin name: desmodus rotundus) in 1761 by the French naturalist Georges Louis Leclerc Comte de Buffon (1707-1788). These bats are known to attack cattle and, very rarely, sleeping human beings. Although their saliva has been shown to contain an anticoagulant compound, they would also be happy to benefit from the pentasaccharide mentioned above, to suck the blood out of the vein more easily. More details about this compound which would be helpful to vampire bats are reported by Petitou, Sinaÿ et al. on p. 1670 ff.
Angewandte Chemie International Edition 06/2001; 40(9):1557. · 13.45 Impact Factor
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Angewandte Chemie International Edition 06/2001; 40(9):1670-1673. · 13.45 Impact Factor
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[show abstract]
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ABSTRACT: A single disaccharide building block is required to obtain synthetic carbohydrates that reproduce the anticoagulant activity of heparin and inhibit thrombin (n>6) and/or factor Xa (n≥2; see reaction scheme). Thus, there is evidence that heparin fragments with at least 15 saccharide units are required for thrombin inhibition. Lev=levulinoyl.
Angewandte Chemie International Edition 12/1998; 37(21):3009 - 3014. · 13.45 Impact Factor
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[show abstract]
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ABSTRACT: A new synthetic route is described toward the hexasaccharide representing the heparin cofactor II binding region of dermatan sulfate. The anti-thrombin activity of this synthetic hexasaccharide is reported here for the first time. This compd. is about two hundred times less active than dermatan sulfate itself for its ability to inhibit thrombin via heparin cofactor II. [on SciFinder(R)]
Bioorg. Med. Chem. Lett. 01/1997; 7(22):2843-2846.
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[show abstract]
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ABSTRACT: (4-O-Levulinyl-α,β-L-idopyranosid)uronate trichloroacetimidate I [Lev = MeCOCH2CH2CO; R = Ac, R1 = OC(CCl3):NH] and the corresponding n-pentyl glycosides I [R = Bz, R1 = O(CH2)3CH:CH2] are efficient L-iduronic acid glycosyl donors. Both have been used for the high-yielding synthesis of basic disaccharide blocks, e.g. II, which are useful for the subsequent synthesis of complex oligosaccharides related to heparin/heparan sulfate, and dermatan sulfate. In contrast, the corresponding thioethyl glycosides I (R = Bz, R1 = SEt), thiophenyl glycosides I (R = Bz, R1 = SPh), and fluoride I (R = Ac, R1 = F), did not yield the expected disaccharides. [on SciFinder(R)]
Carbohydr. Res. 01/1996; 281(2):253-76.
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ABSTRACT: The synthesis is described of the methyl α-glycoside of the pentasaccharide which represents the sequence in heparin responsible for binding and activation of the anticoagulant protein Antithrombin II. It was obtained in a yield much better than that of the previously synthesised pentasaccharide and exhibited the same biological properties.
Carbohydrate Research.
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Tetrahedron Asymmetry 7(11):3119-3128. · 2.65 Impact Factor
