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Severin S, Consonni A, Chicanne G, Allart S, Payrastre B, Gratacap MP. SHIP1 Controls Internal Platelet Contraction and α IIbβ 3 Integrin Dynamics in Early Platelet Activation. Int J Mol Sci 2023; 24:ijms24020958. [PMID: 36674478 PMCID: PMC9860818 DOI: 10.3390/ijms24020958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 12/20/2022] [Accepted: 12/21/2022] [Indexed: 01/06/2023] Open
Abstract
The Src homology 2 domain-containing inositol 5-phosphatase 1 (SHIP1) is known to dephosphorylate PtdIns(3,4,5)P3 into PtdIns(3,4)P2 and to interact with several signaling proteins though its docking functions. It has been shown to negatively regulate platelet adhesion and spreading on a fibrinogen surface and to positively regulate thrombus growth. In the present study, we have investigated its role during the early phase of platelet activation. Using confocal-based morphometric analysis, we found that SHIP1 is involved in the regulation of cytoskeletal organization and internal contractile activity in thrombin-activated platelets. The absence of SHIP1 has no significant impact on thrombin-induced Akt or Erk1/2 activation, but it selectively affects the RhoA/Rho-kinase pathway and myosin IIA relocalization to the cytoskeleton. SHIP1 interacts with the spectrin-based membrane skeleton, and its absence induces a loss of sustained association of integrins to this network together with a decrease in αIIbβ3 integrin clustering following thrombin stimulation. This αIIbβ3 integrin dynamics requires the contractile cytoskeleton under the control of SHIP1. RhoA activation, internal platelet contraction, and membrane skeleton integrin association were insensitive to the inhibition of PtdIns(3,4,5)P3 synthesis or SHIP1 phosphatase activity, indicating a role for the docking properties of SHIP1 in these processes. Altogether, our data reveal a lipid-independent function for SHIP1 in the regulation of the contractile cytoskeleton and integrin dynamics in platelets.
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Affiliation(s)
- Sonia Severin
- Institut des Maladies Métabolique et Cardiovasculaire (I2MC), Inserm and Université Toulouse III Paul-Sabatier (UMR-1297), 1 Avenue J. Poulhes, CEDEX 4, 31432 Toulouse, France
- Correspondence: (S.S.); (M.-P.G.); Tel.: +33-5-31-22-41-43 (S.S.); +33-5-31-22-41-50 (M.-P.G.)
| | - Alessandra Consonni
- Institut des Maladies Métabolique et Cardiovasculaire (I2MC), Inserm and Université Toulouse III Paul-Sabatier (UMR-1297), 1 Avenue J. Poulhes, CEDEX 4, 31432 Toulouse, France
- Laboratory of Biochemistry, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy
| | - Gaëtan Chicanne
- Institut des Maladies Métabolique et Cardiovasculaire (I2MC), Inserm and Université Toulouse III Paul-Sabatier (UMR-1297), 1 Avenue J. Poulhes, CEDEX 4, 31432 Toulouse, France
| | - Sophie Allart
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université Toulouse III Paul-Sabatier and Inserm (UMR-1291) and CNRS (UMR-5051), Centre Hospitalier Universitaire Purpan, CEDEX 3, 31024 Toulouse, France
| | - Bernard Payrastre
- Institut des Maladies Métabolique et Cardiovasculaire (I2MC), Inserm and Université Toulouse III Paul-Sabatier (UMR-1297), 1 Avenue J. Poulhes, CEDEX 4, 31432 Toulouse, France
- Laboratoire d’Hématologie, Centre de Référence des Pathologies Plaquettaires, Centre Hospitalier Universitaire Rangueil, CEDEX 4, 31432 Toulouse, France
| | - Marie-Pierre Gratacap
- Institut des Maladies Métabolique et Cardiovasculaire (I2MC), Inserm and Université Toulouse III Paul-Sabatier (UMR-1297), 1 Avenue J. Poulhes, CEDEX 4, 31432 Toulouse, France
- Correspondence: (S.S.); (M.-P.G.); Tel.: +33-5-31-22-41-43 (S.S.); +33-5-31-22-41-50 (M.-P.G.)
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2
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Song G, Luo BH. Atypical structure and function of integrin α V β 8. J Cell Physiol 2020; 236:4874-4887. [PMID: 33368230 DOI: 10.1002/jcp.30242] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/10/2020] [Accepted: 12/12/2020] [Indexed: 12/12/2022]
Abstract
Integrins are heterodimeric transmembrane proteins that play important roles in various biological processes. Most integrins serve as adhesion molecules and transmit bidirectional signaling across the cell membrane through global conformational changes from the bent closed to the extended open conformation. However, integrin β8 is distinctive in structure and function. Its cytoplasmic domain lacks the conserved protein-binding sequence, which is important in transmitting inside-out signals, suggesting that integrin β8 may have a different activation mechanism or lack such signaling. In addition, the ligand-binding or activating metal ion Mn2+ does not induce a global conformational change in integrin β8 . It may have only one conformation, that is, an extended, closed conformation, but with high affinity for ligands under physiological conditions, and is, therefore, considered an atypical integrin member. The extended structure and high ligand-binding affinity of integrin αv β8 make it ideal for encountering and binding ligands expressed on an opposing cell or in the extracellular matrix. In this review, we summarize the progress in integrin β8 research with a focus on its distinctive function and structure among integrin members.
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Affiliation(s)
- Guannan Song
- Department of Life Science, University of Louisiana State University, Baton Rouge, Louisiana, USA
| | - Bing-Hao Luo
- Department of Life Science, University of Louisiana State University, Baton Rouge, Louisiana, USA
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Fong KP, Zhu H, Span LM, Moore DT, Yoon K, Tamura R, Yin H, DeGrado WF, Bennett JS. Directly Activating the Integrin αIIbβ3 Initiates Outside-In Signaling by Causing αIIbβ3 Clustering. J Biol Chem 2016; 291:11706-16. [PMID: 27056329 DOI: 10.1074/jbc.m116.716613] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Indexed: 11/06/2022] Open
Abstract
αIIbβ3 activation in platelets is followed by activation of the tyrosine kinase c-Src associated with the carboxyl terminus of the β3 cytosolic tail. Exogenous peptides designed to interact with the αIIb transmembrane (TM) domain activate single αIIbβ3 molecules in platelets by binding to the αIIb TM domain and causing separation of the αIIbβ3 TM domain heterodimer. Here we asked whether directly activating single αIIbβ3 molecules in platelets using the designed peptide anti-αIIb TM also initiates αIIbβ3-mediated outside-in signaling by causing activation of β3-associated c-Src. Anti-αIIb TM caused activation of β3-associated c-Src and the kinase Syk, but not the kinase FAK, under conditions that precluded extracellular ligand binding to αIIbβ3. c-Src and Syk are activated by trans-autophosphorylation, suggesting that activation of individual αIIbβ3 molecules can initiate αIIbβ3 clustering in the absence of ligand binding. Consistent with this possibility, incubating platelets with anti-αIIb TM resulted in the redistribution of αIIbβ3 from a homogenous ring located at the periphery of discoid platelets into nodular densities consistent with clustered αIIbβ3. Thus, these studies indicate that not only is resting αIIbβ3 poised to undergo a conformational change that exposes its ligand-binding site, but it is poised to rapidly assemble into intracellular signal-generating complexes as well.
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Affiliation(s)
- Karen P Fong
- From the Hematology-Oncology Division, Department of Medicine, and
| | - Hua Zhu
- From the Hematology-Oncology Division, Department of Medicine, and
| | - Lisa M Span
- From the Hematology-Oncology Division, Department of Medicine, and
| | - David T Moore
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Kyungchul Yoon
- From the Hematology-Oncology Division, Department of Medicine, and
| | - Ryo Tamura
- the Department of Chemistry and Biochemistry and the BioFrontiers Institute, University of Colorado, Boulder, Colorado 80030, and
| | - Hang Yin
- the Department of Chemistry and Biochemistry and the BioFrontiers Institute, University of Colorado, Boulder, Colorado 80030, and
| | - William F DeGrado
- the Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94158-9001
| | - Joel S Bennett
- From the Hematology-Oncology Division, Department of Medicine, and
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4
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Yurttaş L, Abu Mohsen U, Ozkan Y, Cobanoglu S, Levent S, Kaplancikli ZA. Synthesis and biological evaluation of some dibenzofuran-piperazine derivatives. J Enzyme Inhib Med Chem 2015; 31:1177-83. [PMID: 26581445 DOI: 10.3109/14756366.2015.1108971] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In the present paper, a novel series of dibenzofuran-piperazine derivatives were synthesized via the treatment of N-(2-methoxy-3-dibenzofuranyl)-2-chloroacetamide with substituted piperazine derivatives. The chemical structures of the compounds were elucidated by (1)H NMR, (13)C NMR, mass spectral data; elemental analysis and HPLC analysis. Each derivative was evaluated for antiplatelet activity and anticholinesterase activity. Compound 2 m with 2-furoyl moiety exhibited high percentage inhibition as much as standard drug aspirin on arachidonic acid (AA)-induced platelet aggregation. None of the compounds presented significant inhibitor effect on collagen-induced platelet aggregation. Furthermore, the anticholinesterase activity of the compounds was determined and they did not show promising inhibitor activity compared with standard drug donepezil.
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Affiliation(s)
- Leyla Yurttaş
- a Department of Pharmaceutical Chemistry, Faculty of Pharmacy , Anadolu University , Eskişehir , Turkey
| | - Usama Abu Mohsen
- b Department of Pharmaceutical Chemistry , Faculty of Pharmacy, Al-Azhar University , Gaza , Palestine , and
| | - Yeşim Ozkan
- c Department of Biochemistry , Faculty of Pharmacy, Gazi University , Ankara , Turkey
| | - Simla Cobanoglu
- c Department of Biochemistry , Faculty of Pharmacy, Gazi University , Ankara , Turkey
| | - Serkan Levent
- a Department of Pharmaceutical Chemistry, Faculty of Pharmacy , Anadolu University , Eskişehir , Turkey
| | - Zafer Asım Kaplancikli
- a Department of Pharmaceutical Chemistry, Faculty of Pharmacy , Anadolu University , Eskişehir , Turkey
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Coimbra LS, Steffens JP, Alsadun S, Albiero ML, Rossa C, Pignolo RJ, Spolidorio LC, Graves DT. Clopidogrel Enhances Mesenchymal Stem Cell Proliferation Following Periodontitis. J Dent Res 2015. [PMID: 26220958 DOI: 10.1177/0022034515598273] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Bone formation is dependent on the differentiation of osteoblasts from mesenchymal stem cells (MSCs). In addition to serving as progenitors, MSCs reduce inflammation and produce factors that stimulate tissue formation. Upon injury, MSCs migrate to the periodontium, where they contribute to regeneration. We examined the effect of clopidogrel and aspirin on MSCs following induction of periodontitis in rats by placement of ligatures. We showed that after the removal of ligatures, which induces resolution of periodontal inflammation, clopidogrel had a significant effect on reducing the inflammatory infiltrate. It also increased the number of osteoblasts and MSCs. Mechanistically, the latter was linked to increased proliferation of MSCs in vivo and in vitro. When given prior to inducing periodontitis, clopidogrel had little effect on MSC or osteoblasts numbers. Applying aspirin before or after induction of periodontitis did not have a significant effect on the parameters measured. These results suggest that clopidogrel may have a positive effect on MSCs in conditions where a reparative process has been initiated.
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Affiliation(s)
- L S Coimbra
- Department of Physiology and Pathology, Faculdade de Odontologia de Araraquara, UNESP-Univ Estadual Paulista-Araraquara, São Paulo, Brazil
| | - J P Steffens
- Department of Physiology and Pathology, Faculdade de Odontologia de Araraquara, UNESP-Univ Estadual Paulista-Araraquara, São Paulo, Brazil
| | - S Alsadun
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - M L Albiero
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - C Rossa
- Department of Diagnosis and Surgery, Faculdade de Odontologia de Araraquara, UNESP-Univ Estadual Paulista-Araraquara, São Paulo, Brazil
| | - R J Pignolo
- Department of Medicine and Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - L C Spolidorio
- Department of Physiology and Pathology, Faculdade de Odontologia de Araraquara, UNESP-Univ Estadual Paulista-Araraquara, São Paulo, Brazil
| | - D T Graves
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Dorsam RT, Murugappan S, Ding Z, Kunapuli SP. Clopidogrel: interactions with the P2Y12 receptor and clinical relevance. ACTA ACUST UNITED AC 2015; 8:359-65. [PMID: 14668029 DOI: 10.1080/10245330310001621260] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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7
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Role of Side-Chain Bioisosteres in Determining the Binding Affinity of Click Chemistry Derived RGD Peptidomimetics to αvβ3Integrin. European J Org Chem 2014. [DOI: 10.1002/ejoc.201403129] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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8
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Kim S, Shin BS, Ma E. Synthesis and Caco-2 cell permeability of N-substituted anthranilamide esters as ADP inhibitor in platelets. Arch Pharm Res 2014; 38:1147-56. [PMID: 25325926 DOI: 10.1007/s12272-014-0353-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 02/03/2014] [Indexed: 11/30/2022]
Abstract
Twelve N-substituted anthranilamide esters (1-5, 8, 9, 12, 13, and 15-17) were synthesized and evaluated for their ability to inhibit the in vitro aggregation by washed human platelets induced by adenosine 5'-diphosphate (10 μM). The antiplatelet activity of DL-n-butyl 5-hydroxy-N-(2-phenoxypropionyl)anthranilate (9, IC50 = 10.5 μM) was most active among the tested compounds and ethyl ester 8 (IC50 = 11.2 μM) showed the second most activity. DL-Ethyl and DL-n-butyl 5-(p-toluenesulfonyloxy)-N-(2-phenoxypropionyl)anthranilate (12, IC50 = 13.1 μM and 13, IC50 = 14.0 μM), DL-methyl N-(2-phenoxybutyryl)anthranilate (2, IC50 = 12.7 μM), DL-N-(2-phenoxypropionyl)anthranilic acid (5, IC50 = 13.7 μM) displayed lower antiplatelet activity than 8 and 9. Compound 5 was more active than methyl ester prodrug 1. n-Butyl 5-hydroxy-N-(4'-acetoxybenzoyl)anthranilate (15, IC50 = 28.3 μM) showed moderate activity. Compounds 1 (IC50 = 42.8 μM), 4 (IC50 = 56.7 μM), 16 (IC50 = 51.0 μM), and 17 (IC50 = 49.8 μM) exhibited low antiplatelet activity. Methyl N-phenoxyacetylanthranilate (3, IC50 = 78.0 μM) showed the lowest antiplatelet activity. The compounds with branched alkyl chain (2 and 5) were more active than compounds with straight chain (3 and 4). The apparent permeability coefficient (Papp, cm/s) values of compounds 2 and 9 were determined as 45.34 ± 4.67 and 33.17 ± 5.15 × 10(-6) cm/s by Caco-2 cell permeability assay.
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Affiliation(s)
- Sohee Kim
- College of Pharmacy, Catholic University of Daegu, 712-702, Hayangro 13-13, Gyeongsan, 712-702, Korea
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9
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Jing BB, Li YX, Zhang H, Ren ST, Wang M, Li YP, Shen XL, Wang YL, Zang WJ, Wang B. Antithrombotic effect of Z4A5 on coronary thrombosis in a canine model of acute unstable angina. Br J Pharmacol 2014; 169:848-59. [PMID: 23083032 DOI: 10.1111/bph.12026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 08/30/2012] [Accepted: 09/24/2012] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND PURPOSE The glycoprotein IIb/IIIa receptor is the final common pathway of platelet aggregation, regardless of the agonist, and thus represents an ideal therapeutic target for blocking coronary thrombosis. In this study, the anti-platelet and antithrombotic actions of Z4A5, a new glycoprotein IIb/IIIa receptor inhibitor, were evaluated in a canine model of acute unstable angina. EXPERIMENTAL APPROACH Z4A5 was given i.v. as a bolus followed by 60 min of continuous infusion at doses of 30 μg·kg⁻¹ + 1 μg·kg⁻¹·min⁻¹, 30 μg·kg⁻¹ + 5 μg·kg⁻¹·min⁻¹ or 300 μg·kg⁻¹ + 5 μg·kg⁻¹·min⁻¹. Its antithrombotic effect was evaluated in a model of coronary thrombosis, the injured, stenosed left circumflex coronary artery, in which platelet-dependent cyclic flow reductions (CFRs) were induced by vascular compression and constriction to simulate clinical acute unstable angina. Platelet aggregation and coagulation parameters were determined in platelet-rich plasma and platelet poor plasma respectively. KEY RESULTS The Z4A5 infusion induced a dose-dependent reduction in CFR frequency, which returned to baseline levels after the termination of the infusion at low doses. At medium dose that inhibited most part of platelet aggregation, it increased tongue bleeding time marginally with no dramatic changes in haemodynamic and coagulation parameters. Furthermore, the inhibition of ADP-induced platelet aggregation and prolonged bleeding time observed during Z4A5 infusion reverted to baseline levels after the termination of the infusion. CONCLUSIONS AND IMPLICATIONS Z4A5 is an effective antithrombotic agent for coronary artery thrombosis with a rapid-on and rapid-off pharmacological profile, and could be used as an alternative treatment of coronary artery ischaemic syndromes.
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Affiliation(s)
- Bo-Bin Jing
- School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi, China
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10
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Tsai WJ, Shen CC, Tsai TH, Lin LC. Lignans from the aerial parts of Saururus chinensis: isolation, structural characterization, and their effects on platelet aggregation. JOURNAL OF NATURAL PRODUCTS 2014; 77:125-131. [PMID: 24387347 DOI: 10.1021/np400772h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Five new diaryldimethylbutane lignans, saurulignans A-E (1-5), four new tetrahydrofuran lignans, saurufurins A-D (6-9), and one arylnaphthalene lignan, saurunarin (10), were isolated from Saururus chinensis, along with 18 known compounds. Lignan 5 showed significant inhibition of ADP-induced aggregation with an IC50 value of 9.8 μM and AA-induced aggregation with an IC50 value of 14.0 μM. Compound 19 showed significant activity to inhibit PAF-induced aggregation with an IC50 value of 9.1 μM. In addition, five isolated compounds could induce platelet aggregation. These results suggest that secondary metabolites in S. chinensis have bidirectional regulation on blood clotting and anticlotting effects.
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Affiliation(s)
- Wei-Jern Tsai
- National Research Institute of Chinese Medicine , Taipei, Taiwan
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11
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Coimbra LS, Steffens JP, Rossa C, Graves DT, Spolidorio LC. Clopidogrel enhances periodontal repair in rats through decreased inflammation. J Clin Periodontol 2014; 41:295-302. [PMID: 24433307 DOI: 10.1111/jcpe.12203] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/17/2013] [Indexed: 12/18/2022]
Abstract
AIM We hypothesized that platelet inactivation induced by drugs might interfere with periodontal repair in experimental periodontitis by suppressing the release of biological mediators from platelets at the site of injury. MATERIAL AND METHODS Sixty rats were randomly assigned to six groups (n = 10) and ligatures were placed around lower first molars of three groups. The other three groups were used as negative controls. Ligatures were removed after 10 days of periodontitis induction and all groups were submitted to treatment with aspirin (Asp) (30 mg/kg), clopidogrel (Clop) (75 mg/kg) or NaCl 0.9% intra-gastrically once daily for 3 days. Periodontal tissue was assessed by the measurement of CXCL12, CXCL4, CCL5 and platelet-derived growth factor (PDGF) by enzyme-linked immunosorbent assay; histomorphometrical analysis of polymorphonuclear (PMN) infiltration, attachment loss, bone loss and osteoclast numbers and quantification of blood vessels by imunnohistochemistry. RESULTS During periodontal repair and treatment with NaCl 0.9%, CCL5 was decreased and CXCL12 increased when compared with negative control groups. Asp and Clop did not affect CCL5 expression, decreased CXCL12 but only Clop decreased CXCL4 and PDGF content compared with saline-treated animals. Clop increased blood vessel number, reduced PMN count and decreased attachment and bone loss, also decreased osteoclast number in animals submitted or not to periodontal repair. CONCLUSION Systemic administration of Clop for 3 days improved the repair process associated with experimental periodontal disease, suggesting that it may have therapeutic value under situations where tissues undergo a transition from inflammation to repair.
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Affiliation(s)
- Leila S Coimbra
- Department of Physiology and Pathology, Faculdade de Odontologia de Araraquara, UNESP-Univ Estadual Paulista, Araraquara, Brazil
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12
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Coimbra LS, Steffens JP, Muscará MN, Rossa C, Spolidorio LC. Antiplatelet drugs reduce the immunoinflammatory response in a rat model of periodontal disease. J Periodontal Res 2013; 49:729-35. [DOI: 10.1111/jre.12155] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2013] [Indexed: 12/01/2022]
Affiliation(s)
- L. S. Coimbra
- Department of Physiology and Pathology; Faculdade de Odontologia de Araraquara; UNESP-Universidade Estadual Paulista; Araraquara SP Brazil
| | - J. P. Steffens
- Department of Physiology and Pathology; Faculdade de Odontologia de Araraquara; UNESP-Universidade Estadual Paulista; Araraquara SP Brazil
| | - M. N. Muscará
- Department of Pharmacology; Institute of Biomedical Sciences; Universidade de São Paulo São Paulo SP Brazil
| | - C. Rossa
- Department of Diagnosis and Surgery; Faculdade de Odontologia de Araraquara; UNESP-Universidade Estadual Paulista; Araraquara SP Brazil
| | - L. C. Spolidorio
- Department of Physiology and Pathology; Faculdade de Odontologia de Araraquara; UNESP-Universidade Estadual Paulista; Araraquara SP Brazil
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13
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Enhanced cell adhesion and mature intracellular structure promoted by squaramide-based RGD mimics on bioinert surfaces. Bioorg Med Chem 2013; 21:2210-2216. [DOI: 10.1016/j.bmc.2013.02.032] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 02/05/2013] [Accepted: 02/13/2013] [Indexed: 01/21/2023]
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14
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Novel 1,3-diarylpyrazole acrylamides: synthesis, antiplatelet activity screening, and in silico evaluation studies. Med Chem Res 2013. [DOI: 10.1007/s00044-013-0580-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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15
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Abstract
Atherothrombosis often underlies coronary artery disease, stroke, and peripheral arterial disease. Antiplatelet drugs have come to the forefront of prophylactic treatment of atherothrombotic disease. Dual antiplatelet therapy of aspirin plus clopidogrel-the current standard-has benefits, but it also has limitations with regard to pharmacologic properties and adverse effects with often severe bleeding complications. For these reasons, within the last decade or so, the investigation of novel antiplatelet targets has prospered. Target identification can be the result of large-scale genomic or proteomic studies, functional genomics in animal models, the genetic analysis of patients with inherited bleeding disorders, or a combination of these techniques.
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16
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Synthesis of 2H-benzo[b][1,4]oxazin-3(4H)-one derivatives as platelet aggregation inhibitors. Bioorg Med Chem Lett 2012; 22:204-6. [DOI: 10.1016/j.bmcl.2011.11.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 10/20/2011] [Accepted: 11/09/2011] [Indexed: 11/24/2022]
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17
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Structure–activity relationships of chalcone analogs as potential inhibitors of ADP- and collagen-induced platelet aggregation. Bioorg Med Chem 2011; 19:7711-9. [DOI: 10.1016/j.bmc.2011.08.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 07/26/2011] [Accepted: 08/02/2011] [Indexed: 11/18/2022]
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18
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Jing BB, Li YX, Zhang H, Ren ST, Wang M, Li YP, Zang WJ, Wang B. Antithrombotic activity of Z4A5, a new platelet glycoprotein IIb/IIIa receptor antagonist evaluated in a rabbit arteriovenous shunt thrombosis model. Thromb Res 2011; 128:463-9. [PMID: 21924458 DOI: 10.1016/j.thromres.2011.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Revised: 07/05/2011] [Accepted: 08/02/2011] [Indexed: 10/17/2022]
Abstract
INTRODUCTION The antithrombotic effect of the glycopreotein IIb/IIIa (GP IIb/IIIa) receptor antagonist Z4A5, exert alone or combination with heparin, and/or aspirin, was examined in a rabbit arteriovenous shunt thrombosis model. MATERIALS AND METHODS Thrombosis was induced by the insertion of a silk thread (thrombogenic substrate) into an extracorporeal shunt. Before and after drug administration (0, 5, and 15 min), ex vivo adenosine diphosphate (ADP)-induced platelet aggregation and coagulation parameters (prothrombin time (PT) and activated partial thromboplastin time (APTT)) were determined in platelet-rich plasma (PRP) and platelet poor-plasma (PPP), respectively. RESULTS Our data demonstrated that, compared to the control, Z4A5 decreased the thrombus weight (31-65%) in a dose-dependent manner and inhibited ADP-induced platelet aggregation (47-98%) 5 min after Z4A5 administration (25-100 mg/kg). However, PT and APTT remained stable, even at the highest dose (100 mg/kg). Heparin (100 U/kg) and aspirin (15 mg/kg) also significantly reduced thrombus mass, but this effect was accompanied by an increase of APTT by heparin. Furthermore, the combination of heparin (100 U/kg) and a low dose of Z4A5 (25 mg/kg) failed to produce an additional benefit beyond that provided by heparin or Z4A5 alone, whereas Z4A5 (25 mg/kg) plus aspirin (15 mg/kg) potentiated the antithrombotic effects of both compounds without further increasing the values of coagulation. CONCLUSIONS Our results indicate that Z4A5 is an effective antithrombotic agent with no significant effects on values of coagulation. Furthermore, Z4A5 can potentiate these antithrombotic effects when prescribed with aspirin.
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Affiliation(s)
- Bo-Bin Jing
- School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi, China
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Investigation of interaction of human platelet membrane components with anticoagulant drugs Abciximab and Eptifibatide. Folia Histochem Cytobiol 2011; 48:687-92. [PMID: 21478117 DOI: 10.2478/v10042-010-0090-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abciximab (Abci) and eptifibatide (Epti) are antiaggregate drugs which may reduce thrombotic complications in acute coronary syndromes. The aim of this work was the investigation of the interaction between the phospholipid-GPIIb/IIIa glycoprotein complex and Abci or Epti, and the influence of these drugs on the phospholipid ratio in the platelet membrane. The interaction between the phospholipid-GPIIb/IIIa glycoprotein complex and antiaggregate drugs were investigated using the Surface Plasmon Resonance Imaging technique (SPRI). Phospholipids phosphatidylinositol (PI), phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM) were first immobilized onto the gold chip surface. The phospholipid ratio in the platelet membrane was determined by the HPLC. Only PI, PS, PE and PC were determined. Human platelets treated 'in vitro' with Abci or Epti exhibit changes in the phospholipid ratio in the platelet membrane. The ratio of PS decreases and PC rises. The SPRI distinctly shows interactions between phospholipids and glycoprotein GPIIb/IIIa, and between the phospholipid-glycoprotein GPIIb/IIIa complex and Abci or Epti. The interaction between phospholipids and glycoprotein GPIIb/IIIa is growing in the sequence: PI<<SM<PE<PC<PS. The interaction between phospholipid-glycoprotein GPIIb/IIIa complex and Abci/Epti is growing in the sequence: PS<PI<PC<PE<SM. SPRI was proved to be excellent tool for observation of such interactions.
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Grice ID, Rogers KL, Griffiths LR. Isolation of Bioactive Compounds That Relate to the Anti-Platelet Activity of Cymbopogon ambiguus. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2011; 2011:467134. [PMID: 20047890 PMCID: PMC3135635 DOI: 10.1093/ecam/nep213] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Accepted: 11/19/2009] [Indexed: 11/17/2022]
Abstract
Infusions and decoctions of Cymbopogon ambiguus have been used traditionally in Australia for the treatment of headache, chest infections and muscle cramps. The aim of the present study was to screen and identify bioactive compounds from C. ambiguus that could explain this plant's anti-headache activity. A dichloromethane extract of C. ambiguus was identified as having activity in adenosine-diphosphate-induced human platelet aggregation and serotonin-release inhibition bioassays. Subsequent fractionation of this extract led to the isolation of four phenylpropenoids, eugenol, elemicin, eugenol methylether and trans-isoelemicin. While both eugenol and elemicin exhibited dose-dependent inhibition of ADP-induced human platelet serotonin release, only eugenol displayed potent inhibitory activity with an IC50 value of 46.6 μM, in comparison to aspirin, with an IC50 value of 46.1 μM. These findings provide evidence to support the therapeutic efficacy of C. ambiguus in the non-conventional treatment of headache and inflammatory conditions.
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Affiliation(s)
- I Darren Grice
- Institute for Glycomics, Gold Coast campus, Griffith University, Queensland, 4222, Australia
| | - Kelly L Rogers
- Plate-forme d'imagerie dynamique, Institut Pasteur, Paris Cedex 15, France; Genomics Research Centre, Gold Coast campus, Griffith University, Queensland, 4222, Australia
| | - Lyn R Griffiths
- Genomics Research Centre, Gold Coast campus, Griffith University, Queensland, 4222, Australia
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Coimbra LS, Rossa C, Guimarães MR, Gerlach RF, Muscará MN, Spolidorio DMP, Herrera BS, Spolidorio LC. Influence of antiplatelet drugs in the pathogenesis of experimental periodontitis and periodontal repair in rats. J Periodontol 2010; 82:767-77. [PMID: 21073332 DOI: 10.1902/jop.2010.100555] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Platelets contain an array of biologic mediators that can modulate inflammation and repair processes including proinflammatory mediators and growth factors. Previous studies have shown that periodontitis and periodontal repair are associated with platelet activation. We hypothesized that drug-induced platelet inactivation may interfere in the processes of inflammation and repair in experimental periodontitis in rats by suppressing the release of biologic mediators from platelets to the site of injury. METHODS To measure the effects on periodontitis, ligatures were placed around first molars, and aspirin (Asp, 30 mg/kg) or clopidogrel (Clo, 75 mg/kg) was given intragastrically once daily for 15 days. Interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and thromboxane A(2) levels were measured by enzyme-linked immunosorbent assay. To evaluate the effects of antiplatelet drugs on periodontal repair, ligatures were removed after 15 days of periodontitis induction, and Asp or Clo were administered beginning the following day for 15 days. Periodontal repair was assessed by microcomputed tomography. RESULTS On periodontitis phase, Asp and Clo significantly reduced levels of TNF-α and Il-6 (P <0.05), but only Asp decreased thromboxane A(2) (P <0.05). Asp and Clo decreased inflammatory infiltration; however, this reduction was more pronounced with Clo treatment (P <0.05). Histometric analysis showed that Asp and Clo impaired alveolar bone resorption. During the repair phase and after removal of the ligatures, microcomputed tomography analysis demonstrated that treatment with Asp and Clo did not impair alveolar bone repair. CONCLUSION Systemic administration of Asp and Clo attenuates the inflammation associated with periodontitis without affecting the repair process when stimulus is removed.
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Affiliation(s)
- Leila S Coimbra
- Department of Physiology and Pathology, Faculdade de Odontologia de Araraquara, UNESP, Universidade Estadual Paulista, Araraquara, SP, Brazil
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Gresham C, Levine M, Ruha AM. Case files of the Medical Toxicology Fellowship at Banner Good Samaritan Medical Center in Phoenix, AZ: a non-warfarin anticoagulant overdose. J Med Toxicol 2010; 5:242-9. [PMID: 19876861 DOI: 10.1007/bf03178275] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
A 50-year-old man presented to the emergency department (ED) following an overdose of his "blood thinners." The patient had become increasingly depressed over financial concerns, prompting a suicide attempt. He declined to provide any details regarding his current medications or his past medical history. A review of the computerized medical record, however, revealed he had a Factor V Leiden mutation with multiple venothromboembolic events. He previously had an inferior vena cava filter placed, and had received tissue plasminogen activator (tPA) for a cerebrovascular accident. A toxicology consult was obtained in the ED.
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Affiliation(s)
- Chip Gresham
- Department of Medical Toxicology, Banner Good Samaritan Medical Center, Banner Poison Control Center, Phoenix, AZ 85006, USA
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23
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Sun D, McNicol A, James AA, Peng Z. Expression of functional recombinant mosquito salivary apyrase: A potential therapeutic platelet aggregation inhibitor. Platelets 2009; 17:178-84. [PMID: 16702045 DOI: 10.1080/09537100500460234] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Excessive platelet activation and accumulation can lead to vessel occlusion and thus present major therapeutic challenges in cardiovascular medicine. Apyrase, an ecto-enzyme with ADPase and ATPase activities, rapidly metabolizes ADP and ATP released from platelets and endothelial cells, thereby reducing platelet activation and recruitment. In the present study, we expressed a 68-kDa recombinant mosquito (Aedes aegypti) salivary apyrase using a baculovirus/insect cell expression system and purified it to homogeneity using anion-exchange chromatography on a large scale. A yield of 18 mg of purified recombinant apyrase was obtained from 1 litre of the medium. Kinetic analysis indicated that the recombinant apyrase had a K(m) of 12.5 microM for ADP and a K(m) of 15.0 microM for ATP. The recombinant apyrase inhibited ADP-, collagen- and thrombin-induced human platelet aggregation in a dose-dependent manner, indicating that the recombinant protein retained nucleotidase activity in a whole cell system, which suggests that it may serve as a therapeutic agent for inhibition of platelet-mediated thrombosis.
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Affiliation(s)
- Dongfeng Sun
- Department of Pediatrics and Child Health, Faculty of Medicine, University of Manitoba, Manitoba, Canada
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Abstract
BACKGROUND Integrins are a family of transmembrane receptors that mediate cell-cell and cell-matrix adhesion. They are involved in stable cell adhesion and migration of cells. In addition, integrin-mediated interactions modulate the response to most, if not all growth factors, cytokines, and other soluble factors. PURPOSE In this review, we briefly explain how integrins can affect the multitude of signal transduction cascades in control of survival, proliferation, and differentiation. Subsequently, we primarily focus on targeting integrins alpha5beta1 and alphanubeta3 in disease and we discuss how antagonists of these integrins, including disintegrins, RGD peptides, small molecules, and function blocking antibodies, may be of therapeutical value either alone or, especially in the treatment of cancer, in combination with existing therapeutical strategies.
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Affiliation(s)
- Stephan Huveneers
- Division of Toxicology, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands
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Adhesion of Plasmodium falciparum-infected erythrocytes to human cells: molecular mechanisms and therapeutic implications. Expert Rev Mol Med 2009; 11:e16. [PMID: 19467172 PMCID: PMC2878476 DOI: 10.1017/s1462399409001082] [Citation(s) in RCA: 249] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Severe malaria has a high mortality rate (15–20%) despite treatment with
effective antimalarial drugs. Adjunctive therapies for severe malaria that target the
underlying disease process are therefore urgently required. Adhesion of erythrocytes
infected with Plasmodium falciparum to human cells has a key role in the
pathogenesis of life-threatening malaria and could be targeted with antiadhesion therapy.
Parasite adhesion interactions include binding to endothelial cells (cytoadherence),
rosetting with uninfected erythrocytes and platelet-mediated clumping of infected
erythrocytes. Recent research has started to define the molecular mechanisms of parasite
adhesion, and antiadhesion therapies are being explored. However, many fundamental
questions regarding the role of parasite adhesion in severe malaria remain unanswered.
There is strong evidence that rosetting contributes to severe malaria in sub-Saharan
Africa; however, the identity of other parasite adhesion phenotypes that are implicated in
disease pathogenesis remains unclear. In addition, the possibility of geographic variation
in adhesion phenotypes causing severe malaria, linked to differences in malaria
transmission levels and host immunity, has been neglected. Further research is needed to
realise the untapped potential of antiadhesion adjunctive therapies, which could
revolutionise the treatment of severe malaria and reduce the high mortality rate of the
disease.
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Vyas SP, Vaidya B. Targeted delivery of thrombolytic agents: role of integrin receptors. Expert Opin Drug Deliv 2009; 6:499-508. [DOI: 10.1517/17425240902878002] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Dupont AG, Gabriel DA, Cohen MG. Antiplatelet therapies and the role of antiplatelet resistance in acute coronary syndrome. Thromb Res 2009; 124:6-13. [DOI: 10.1016/j.thromres.2009.01.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 01/20/2009] [Accepted: 01/25/2009] [Indexed: 11/16/2022]
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Luo BH, Karanicolas J, Harmacek LD, Baker D, Springer TA. Rationally designed integrin beta3 mutants stabilized in the high affinity conformation. J Biol Chem 2008; 284:3917-24. [PMID: 19019827 DOI: 10.1074/jbc.m806312200] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Integrins are important cell surface receptors that transmit bidirectional signals across the membrane. It has been shown that a conformational change of the integrin beta-subunit headpiece (i.e. the beta I domain and the hybrid domain) plays a critical role in regulating integrin ligand binding affinity and function. Previous studies have used coarse methods (a glycan wedge, mutations in transmembrane contacts) to force the beta-subunit into either the open or closed conformation. Here, we demonstrate a detailed understanding of this conformational change by applying computational design techniques to select five amino acid side chains that play an important role in the energetic balance between the open and closed conformations of alphaIIbbeta3. Eight single-point mutants were designed at these sites, of which five bound ligands much better than wild type. Further, these mutants were found to be in a more extended conformation than wild type, suggesting that the conformational change at the ligand binding headpiece was propagated to the legs of the integrin. This detailed understanding of the conformational change will assist in the development of allosteric drugs that either stabilize or destabilize specific integrin conformations without occluding the ligand-binding site.
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Affiliation(s)
- Bing-Hao Luo
- Immune Disease Institute and Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA
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29
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McLane MA, Zhang X, Tian J, Paquette-Straub C. MONOMERIC AND DIMERIC DISINTEGRINS: PLATELET ACTIVE AGENTS FROM VIPER VENOM. TOXIN REV 2008. [DOI: 10.1080/15569540600567420] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Caputo GA, Litvinov RI, Li W, Bennett JS, Degrado WF, Yin H. Computationally designed peptide inhibitors of protein-protein interactions in membranes. Biochemistry 2008; 47:8600-6. [PMID: 18642886 DOI: 10.1021/bi800687h] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We recently reported a computational method (CHAMP) for designing sequence-specific peptides that bind to the membrane-embedded portions of transmembrane proteins. We successfully applied this method to design membrane-spanning peptides targeting the transmembrane domains of the alpha IIb subunit of integrin alpha IIbbeta 3. Previously, we demonstrated that these CHAMP peptides bind specifically with reasonable affinity to isolated transmembrane helices of the targeted transmembrane region. These peptides also induced integrin alpha IIbbeta 3 activation due to disruption of the helix-helix interactions between the transmembrane domains of the alpha IIb and beta 3 subunits. In this paper, we show the direct interaction of the designed anti-alpha IIb CHAMP peptide with isolated full-length integrin alpha IIbbeta 3 in detergent micelles. Further, the behavior of the designed peptides in phospholipid bilayers is essentially identical to their behavior in detergent micelles. In particular, the peptides assume a membrane-spanning alpha-helical conformation that does not disrupt bilayer integrity. The activity and selectivity of the CHAMP peptides were further explored in platelets, comfirming that anti-alpha IIb activates wild-type alpha IIbbeta 3 in whole cells as a result of its disruption of the protein-protein interactions between the alpha and beta subunits in the transmembrane regions. These results demonstrate that CHAMP is a successful chemical biology approach that can provide specific tools for probing the transmembrane domains of proteins.
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Affiliation(s)
- Gregory A Caputo
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, USA
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31
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Kadaveru K, Vyas J, Schiller MR. Viral infection and human disease--insights from minimotifs. FRONT BIOSCI-LANDMRK 2008; 13:6455-71. [PMID: 18508672 DOI: 10.2741/3166] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Short functional peptide motifs cooperate in many molecular functions including protein interactions, protein trafficking, and posttranslational modifications. Viruses exploit these motifs as a principal mechanism for hijacking cells and many motifs are necessary for the viral life-cycle. A virus can accommodate many short motifs in its small genome size providing a plethora of ways for the virus to acquire host molecular machinery. Host enzymes that act on motifs such as kinases, proteases, and lipidation enzymes, as well as protein interaction domains, are commonly mutated in human disease, suggesting that the short peptide motif targets of these enzymes may also be mutated in disease; however, this is not observed. How can we explain why viruses have evolved to be so dependent on motifs, yet these motifs, in general do not seem to be as necessary for human viability? We propose that short motifs are used at the system level. This system architecture allows viruses to exploit a motif, whereas the viability of the host is not affected by mutation of a single motif.
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Affiliation(s)
- Krishna Kadaveru
- University of Connecticut Health Center, Department of Molecular, Microbial, and Structural Biology, Biological Systems Modeling Group, 263 Farmington Ave., Farmington, CT, 06030-3305, USA
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Elad S, Chackartchi T, Shapira L, Findler M. A critically severe gingival bleeding following non-surgical periodontal treatment in patients medicated with anti-platelet. J Clin Periodontol 2008; 35:342-5. [DOI: 10.1111/j.1600-051x.2008.01206.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wassmer SC, Taylor T, Maclennan CA, Kanjala M, Mukaka M, Molyneux ME, Grau GE. Platelet-induced clumping of Plasmodium falciparum-infected erythrocytes from Malawian patients with cerebral malaria-possible modulation in vivo by thrombocytopenia. J Infect Dis 2008; 197:72-8. [PMID: 18171288 DOI: 10.1086/523761] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Platelets may play a role in the pathogenesis of human cerebral malaria (CM), and they have been shown to induce clumping of Plasmodium falciparum-parasitized red blood cells (PRBCs) in vitro. Both thrombocytopenia and platelet-induced PRBC clumping are associated with severe malaria and, especially, with CM. In the present study, we investigated the occurrence of the clumping phenomenon in patients with CM by isolating and coincubating their plasma and PRBCs ex vivo. Malawian children with CM all had low platelet counts, with the degree of thrombocytopenia directly proportional to the density of parasitemia. Plasma samples obtained from these patients subsequently induced weak PRBC clumping. When the assays were repeated, with the plasma platelet concentrations adjusted to within the physiological range considered to be normal, massive clumping occurred. The results of this study suggest that thrombocytopenia may, through reduction of platelet-mediated clumping of PRBCs, provide a protective mechanism for the host during CM.
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Meyers C, Yáñez M, Elmaatougi A, Verhelst T, Coelho A, Fraiz N, Lemière GL, Garcı´a-Mera X, Laguna R, Cano E, Maes BU, Sotelo E. 2-Substituted 4-, 5-, and 6-[(1E)-3-oxo-3-phenylprop-1-en-1-yl]pyridazin-3(2H)-ones and 2-substituted 4,5-bis[(1E)-3-oxo-3-phenylprop-1-en-1-yl]pyridazin-3(2H)-ones as potent platelet aggregation inhibitors: Design, synthesis, and SAR studies. Bioorg Med Chem Lett 2008; 18:793-7. [DOI: 10.1016/j.bmcl.2007.11.034] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Revised: 11/09/2007] [Accepted: 11/10/2007] [Indexed: 12/28/2022]
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35
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Limbach M, Korotkov VS, Es-Sayed M, de Meijere A. High yielding selective access to spirocyclopropanated 5-oxopiperazine-2-carboxylates and 1,4-diazepane-2,5-diones from methyl 2-chloro-2-cyclopropylideneacetate. Org Biomol Chem 2008; 6:3816-22. [DOI: 10.1039/b809174a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Modifying murine von Willebrand factor A1 domain for in vivo assessment of human platelet therapies. Nat Biotechnol 2007; 26:114-9. [PMID: 18084279 DOI: 10.1038/nbt1373] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Accepted: 11/26/2007] [Indexed: 11/09/2022]
Abstract
The A1 domain of von Willebrand factor (VWF-A1) plays a crucial role in hemostasis and thrombosis by initiating platelet adhesion at sites of arterial injury through interactions with the platelet receptor glycoprotein Ib alpha (GPIbalpha). Here we report that murine VWF-A1 supports limited binding of human platelets. However, atomic models of GPIbalpha-VWF-A1 complexes identified an electrostatic 'hot-spot' that, when mutated in murine VWF-A1, switches its binding specificity from mouse to human GPIbalpha. Furthermore, mice expressing this mutant VWF-A1 display a bleeding phenotype that can be corrected by infusion of human platelets. Mechanistically, human platelets correct the phenotype by forming occlusive thrombi, an event that can be abrogated by blockade of GPIbalpha or by the preadministration of inhibitors of platelet activation or adhesion (clopidogrel (Plavix) and abciximab (ReoPro), respectively). Thus, by modifying a protein interface, we have generated a potential biological platform for preclinical screening of antithrombotics that specifically target human platelets.
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Garcia A, Shankar H, Murugappan S, Kim S, Kunapuli S. Regulation and functional consequences of ADP receptor-mediated ERK2 activation in platelets. Biochem J 2007; 404:299-308. [PMID: 17298299 PMCID: PMC1868805 DOI: 10.1042/bj20061584] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We have previously shown that ADP-induced thromboxane generation in platelets requires signalling events from the G(q)-coupled P2Y1 receptor (platelet ADP receptor coupled to stimulation of phospholipase C) and the G(i)-coupled P2Y12 receptor (platelet ADP receptor coupled to inhibition of adenylate cyclase) in addition to outside-in signalling. While it is also known that extracellular calcium negatively regulates ADP-induced thromboxane A2 generation, the underlying mechanism remains unclear. In the present study we sought to elucidate the signalling mechanisms and regulation by extracellular calcium of ADP-induced thromboxane A2 generation in platelets. ERK (extracllular-signal-regulated kinase) 2 activation occurred when outside-in signalling was blocked, indicating that it is a downstream event from the P2Y receptors. However, blockade of either P2Y1 or the P2Y12 receptors with corresponding antagonists completely abolished ERK phosphorylation, indicating that both P2Y receptors are required for ADP-induced ERK activation. Inhibitors of Src family kinases or the ERK upstream kinase MEK [MAPK (mitogen-activated protein kinase)/ERK kinase] abrogated ADP-induced ERK phosphorylation and thromboxane A2 generation. Finally ADP- or G(i)+G(z)-induced ERK phosphorylation was blocked in the presence of extracellular calcium. The present studies show that ERK2 is activated downstream of P2Y receptors through a complex mechanism involving Src kinases and this plays an important role in ADP-induced thromboxane A2 generation. We also conclude that extracellular calcium blocks ADP-induced thromboxane A2 generation through the inhibition of ERK activation.
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Affiliation(s)
- Analia Garcia
- *Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
- †Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
| | - Haripriya Shankar
- *Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
| | - Swaminathan Murugappan
- *Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
- †Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
| | - Soochong Kim
- *Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
- †Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
| | - Satya P. Kunapuli
- *Department of Physiology, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
- †Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
- ‡Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA 19140, U.S.A
- To whom correspondence should be addressed (email )
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39
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Ruiz-Torres MP, Perez-Rivero G, Diez-Marques ML, Griera M, Ortega R, Rodriguez-Puyol M, Rodríguez-Puyol D. Role of activator protein-1 on the effect of arginine-glycine-aspartic acid containing peptides on transforming growth factor-β1 promoter activity. Int J Biochem Cell Biol 2007; 39:133-45. [PMID: 16978906 DOI: 10.1016/j.biocel.2006.07.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2006] [Revised: 07/19/2006] [Accepted: 07/20/2006] [Indexed: 11/24/2022]
Abstract
While arginine-glycine-aspartic acid-based peptidomimetics have been employed for the treatment of cardiovascular disorders and cancer, their use in other contexts remains to be explored. Arginine-glycine-aspartic acid-serine induces Transforming growth factor-beta1 transcription in human mesangial cells, but the molecular mechanisms involved have not been studied extensively. We explored whether this effect could be due to Activator protein-1 activation and studied the potential pathways involved. Addition of arginine-glycine-aspartic acid-serine promoted Activator protein-1 binding to its cognate sequence within the Transforming growth factor-beta1 promoter as well as c-jun and c-fos protein abundance. Moreover, this effect was suppressed by curcumin, a c-Jun N terminal kinase inhibitor, and was absent when the Activator protein-1 cis-regulatory element was deleted. Activator protein-1 binding was dependent on the activity of integrin linked kinase, as transfection with a dominant negative mutant suppressed both Activator protein-1 binding and c-jun and c-fos protein increment. Integrin linked kinase was, in turn, dependent on Phosphoinositol-3 kinase activity. Arginine-glycine-aspartic acid-serine stimulated Phosphoinositol-3 kinase activity, and Transforming growth factor-beta1 promoter activation was abrogated by the use of Phosphoinositol-3 kinase specific inhibitors. In summary, we propose that arginine-glycine-aspartic acid-serine activates Integrin linked kinase via the Phosphoinositol-3 kinase pathway and this leads to activation of c-jun and c-fos and increased Activator protein-1 binding and Transforming growth factor-beta1 promoter activity. These data may contribute to understand the molecular mechanisms involved in the cellular actions of arginine-glycine-aspartic acid-related peptides and enhance their relevance as these products evolve into clinical therapeutic use.
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Affiliation(s)
- M P Ruiz-Torres
- Nephrology Section and Research Unit, Hospital Príncipe de Asturias, Alcalá de Henares, Madrid, Spain.
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Abbracchio MP, Burnstock G, Boeynaems JM, Barnard EA, Boyer JL, Kennedy C, Knight GE, Fumagalli M, Gachet C, Jacobson KA, Weisman GA. International Union of Pharmacology LVIII: update on the P2Y G protein-coupled nucleotide receptors: from molecular mechanisms and pathophysiology to therapy. Pharmacol Rev 2006; 58:281-341. [PMID: 16968944 PMCID: PMC3471216 DOI: 10.1124/pr.58.3.3] [Citation(s) in RCA: 987] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
There have been many advances in our knowledge about different aspects of P2Y receptor signaling since the last review published by our International Union of Pharmacology subcommittee. More receptor subtypes have been cloned and characterized and most orphan receptors de-orphanized, so that it is now possible to provide a basis for a future subdivision of P2Y receptor subtypes. More is known about the functional elements of the P2Y receptor molecules and the signaling pathways involved, including interactions with ion channels. There have been substantial developments in the design of selective agonists and antagonists to some of the P2Y receptor subtypes. There are new findings about the mechanisms underlying nucleotide release and ectoenzymatic nucleotide breakdown. Interactions between P2Y receptors and receptors to other signaling molecules have been explored as well as P2Y-mediated control of gene transcription. The distribution and roles of P2Y receptor subtypes in many different cell types are better understood and P2Y receptor-related compounds are being explored for therapeutic purposes. These and other advances are discussed in the present review.
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Affiliation(s)
- Maria P Abbracchio
- Department of Pharmacological Sciences, University of Milan, Milan, Italy
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41
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Yang J, Yao J, Chen L, Yang J. The Amino-terminal domain of tntegrin beta3 functions as a transcriptional activator in yeast. Mol Cell Biochem 2006; 288:1-5. [PMID: 16858512 DOI: 10.1007/s11010-005-9078-2] [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: 06/26/2005] [Accepted: 11/10/2005] [Indexed: 10/24/2022]
Abstract
A deletion mutant encoding the integrin beta3(4I-F56) with an additional Gln at the carboxyl terminus was found occassionally when we were constructing a counterselection yeast two-hybrid assay modle. This mutant exhibited strong transcriptional activation in yeast cells, bearing the Escherichia coli lacZ reporter gene encoding the beta-galactosidase under the transcriptional control of GAL4 promoter and TATA box. Further analysis revealed that the region between the amino acid residues 23C to S77, an acidic domain involved in the function of several transcriptional activators were critical for optimal level of transactivation.
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Affiliation(s)
- Jianbo Yang
- State Key Laboratory of Pharmaceutical Biotechnology, College of Life Science, Nanjing University, Nanjing, 210093, China.
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42
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Kannan S. Molecular basis of the clinical failure of Clopidogrel therapy. Med Hypotheses 2006; 67:200-1. [PMID: 16504412 DOI: 10.1016/j.mehy.2006.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2005] [Accepted: 01/10/2006] [Indexed: 11/22/2022]
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Abstract
The platelet integrin alpha(IIb)beta(3) is required for platelet aggregation. Like other integrins, alpha(IIb)beta(3) resides on cell surfaces in an equilibrium between inactive and active conformations. Recent experiments suggest that the shift between these conformations involves a global reorganization of the alpha(IIb)beta(3) molecule and disruption of constraints imposed by the heteromeric association of the alpha(IIb) and beta(3) transmembrane and cytoplasmic domains. The biochemical, biophysical, and ultrastructural results that support this conclusion are discussed in this Review.
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Affiliation(s)
- Joel S Bennett
- Hematology-Oncology Division, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6058, USA.
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44
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Israels SJ, Michelson AD. Antiplatelet therapy in children. Thromb Res 2006; 118:75-83. [PMID: 16709476 DOI: 10.1016/j.thromres.2004.12.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2004] [Revised: 07/29/2004] [Accepted: 12/23/2004] [Indexed: 01/19/2023]
Abstract
Platelets are essential for the maintenance of vascular integrity and control of bleeding at sites of injury, but they are also implicated in the progression of atherosclerotic lesions and arterial vascular thrombosis. The use of antiplatelet drugs for the primary and secondary prevention of cardiovascular and cerebrovascular thromboses in adult populations has been extensively evaluated, resulting in defined management strategies. Much less is known about the appropriate use of antiplatelet drugs (primarily aspirin) in infants and children for secondary prevention in ischemic stroke, for prevention of coronary artery thrombosis in Kawasaki disease, or for prevention of thromboembolism following surgery for congenital cardiac disease. Additional studies will be required to evaluate the relative benefits of aspirin and anticoagulants in these settings. A role for newer antiplatelet drugs in the management of pediatric arterial thrombosis is as yet unexplored.
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Affiliation(s)
- Sara J Israels
- Department of Pediatrics and Child Health, and the Manitoba Institute of Cell Biology, University of Manitoba, Winnipeg, Manitoba, Canada R3E 0V9.
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45
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Zhao LM, Jin HS, Sun LP, Piao HR, Quan ZS. Synthesis and evaluation of antiplatelet activity of trihydroxychalcone derivatives. Bioorg Med Chem Lett 2005; 15:5027-9. [PMID: 16169724 DOI: 10.1016/j.bmcl.2005.08.039] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2005] [Revised: 07/16/2005] [Accepted: 08/01/2005] [Indexed: 11/24/2022]
Abstract
In an effort to develop potent antiplatelet agents, a series of trihydroxychalcones was synthesized and screened in vitro for their inhibitory effects on washed rabbit platelet aggregation induced by arachidonic acid (100 microM) and collagen (10 microg/ml). Of five compounds with potent inhibitory effects on arachidonic acid- and collagen-induced platelet aggregation, compound 4e was found to be the most potent. The structure-activity relationships suggested that antiplatelet activity was governed to a greater extent by the substituent on B ring of the chalcone template, and most of the active compounds had methoxy or dimethoxy groups on B ring.
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Affiliation(s)
- Li-Ming Zhao
- College of Pharmacy, Yanbian University, 121 Juzi Street, Yanji 133000, Jilin, China
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46
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Kidane AG, Salacinski H, Tiwari A, Bruckdorfer KR, Seifalian AM. Anticoagulant and antiplatelet agents: their clinical and device application(s) together with usages to engineer surfaces. Biomacromolecules 2005; 5:798-813. [PMID: 15132664 DOI: 10.1021/bm0344553] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An essential aspect of the treatment of patients with cardiovascular disease is the use of anticoagulant and antiplatelet agents for the prevention of further ischaemic events and vascular death resulting from thrombosis. Aspirin and heparin have been the standard therapy for the management of such conditions to date. Recently, numerous more potent platelet inhibitors together with anticoagulant agents have been developed and tested in randomized clinical trials. This article reviews the current state of the art of antiplatelet and anticoagulant therapy in light of its potential clinical efficacy. It then focuses on the usages of these agents in order to improve the performance of clinical devices such as balloon catheters, coronary stents, and femoropopliteal bypass grafting and extra corporeal circuits for cardiopulmonary bypass. The article then goes on to look at the usage of these agents more specifically heparin, heparan, hirudin, and coumarin in the development of more biocompatible scaffolds for tissue engineering.
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Affiliation(s)
- Asmeret G Kidane
- University Department of Surgery, Royal Free and University College Medical School, University College London, Royal Free Hospital, London NW3 2QG, United Kingdom
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47
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Anderluh M, Cesar J, Stefanic P, Kikelj D, Janes D, Murn J, Nadrah K, Tominc M, Addicks E, Giannis A, Stegnar M, Dolenc MS. Design and synthesis of novel platelet fibrinogen receptor antagonists with 2H-1,4-benzoxazine-3(4H)-one scaffold. A systematic study. Eur J Med Chem 2005; 40:25-49. [PMID: 15642407 DOI: 10.1016/j.ejmech.2004.09.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2004] [Revised: 09/01/2004] [Accepted: 09/06/2004] [Indexed: 11/29/2022]
Abstract
New platelet glycoprotein IIb/IIIa (GP IIb/IIIa, integrin alpha(IIb)beta3) antagonists were prepared on a 2H-1,4-benzoxazine-3(4H)-one scaffold. Their anti-aggregatory activities in human platelet rich plasma and their affinity towards alpha(IIb)beta3 and alpha(V)beta3 integrins were assessed. Various substitution positions and side chain variations were studied. In contrast to the generally accepted model, compounds containing ethyl esters as aspartate mimetics were in general more active than the corresponding free acids. We suggest an explanation for the observed behaviour of these new compounds.
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Affiliation(s)
- Marko Anderluh
- Faculty of Pharmacy, University of Ljubljana, Askerceva 7, 1000 Ljubljana, Slovenia
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Hogan DF, Andrews DA, Green HW, Talbott KK, Ward MP, Calloway BM. Antiplatelet effects and pharmacodynamics of clopidogrel in cats. J Am Vet Med Assoc 2004; 225:1406-11. [PMID: 15552317 DOI: 10.2460/javma.2004.225.1406] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate antiplatelet effects and pharmacodynamics of clopidogrel in cats. DESIGN Original study. ANIMALS 5 purpose-bred domestic cats. PROCEDURE Clopidogrel was administered at dosages of 75 mg, p.o., every 24 hours for 10 days; 37.5 mg, p.o., every 24 hours for 10 days; and 18.75 mg, p.o., every 24 hours for 7 days. In all cats, treatments were administered in this order, with at least 2 weeks between treatments. Platelet aggregation in response to ADP and collagen and oral mucosal bleeding times (OMBTs) were measured before and 3, 7, and 10 days (75 and 37.5 mg) or 7 days (18.75 mg) after initiation of drug administration. Serotonin concentration in plasma following stimulation of platelets with ADP or collagen was measured before and on the last day of drug administration. Platelet aggregation, OMBT, and serotonin concentration were evaluated at various times after drug administration was discontinued to determine when drug effects were lost. RESULTS For all 3 dosages, platelet aggregation in response to ADP platelet aggregation in response to collagen, and serotonin concentration were significantly reduced and OMBT was significantly increased at all measurement times during drug administration periods. All values returned to baseline values by 7 days after drug administration was discontinued. No significant differences were identified between doses. None of the cats developed adverse effects associated with drug administration. CONCLUSIONS AND CLINICAL RELEVANCE Results suggest that administration of clopidogrel at dosages ranging from 18.75 to 75 mg, p.o., every 24 hours, results in significant antiplatelet effects in cats.
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Affiliation(s)
- Daniel F Hogan
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA
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Omi H, Okayama N, Shimizu M, Fukutomi T, Nakamura A, Imaeda K, Okouchi M, Itoh M. Cilostazol inhibits high glucose-mediated endothelial-neutrophil adhesion by decreasing adhesion molecule expression via NO production. Microvasc Res 2004; 68:119-25. [PMID: 15313121 DOI: 10.1016/j.mvr.2004.05.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2003] [Indexed: 10/26/2022]
Abstract
OBJECTIVE Endothelial-neutrophil adhesion is crucial for vascular injury, the major cause of diabetic vascular complications. On the other hand, platelet aggregation inhibitors, frequently used for diabetic patients with intermittent claudication, have been shown to decrease the incidence of atherosclerosis-mediated diseases (acute myocardial infarction and stroke). However, whether these agents act directly on the endothelial reactions to hyperglycemia remains unclear. Therefore, we examined their direct effects on endothelial-neutrophil adhesion and expression of endothelial adhesion molecules induced by high glucose. METHODS AND RESULTS After human endothelial cells were cultured in high glucose medium, neutrophils from healthy volunteers were added and allowed to adhere for 30 min. Adhered neutrophils were quantified by measuring their myeloperoxidase (MPO) activities, and surface expression of endothelial adhesion molecules was determined with an enzyme immunoassay. Of the platelet aggregation inhibitors tested, only cilostazol significantly attenuated the adhesion through decreasing expression of intercellular adhesion molecule-1 (ICAM-1) and P-selectin. In addition, nitric oxide (NO) synthase inhibitors reduced the inhibitory effects of cilostazol, but a protein kinase C (PKC) activator did not. CONCLUSIONS Cilostazol may act directly on endothelial cells to inhibit expression of adhesion molecules and neutrophil adhesion induced by high glucose through increasing NO production.
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Affiliation(s)
- Hitoshi Omi
- Department of Internal Medicine and Bioregulation, Nagoya City University Graduate School of Medical Sciences, Nagoya 467-8601, Japan
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50
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Jin YR, Ryu CK, Moon CK, Cho MR, Yun YP. Inhibitory effects of J78, a newly synthesized 1,4-naphthoquinone derivative, on experimental thrombosis and platelet aggregation. Pharmacology 2004; 70:195-200. [PMID: 15001820 DOI: 10.1159/000075548] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2003] [Accepted: 09/17/2003] [Indexed: 11/19/2022]
Abstract
Several compounds with the backbone of 1,4-naphthoquinone chemical structure have been reported to display antiplatelet and antithrombotic activities, indicating that this congener compound may be a new source in the antithrombotic drug development. In the present study, the possible antiplatelet activity and antithrombotic efficacy of J78 (2-chloro-3-[2'-bromo, 4'-fluoro- phenyl]-amino-8-hydroxy-1,4-naphthoquinone), a newly synthesized 1,4-naphthoquinone derivative, were examined. Orally administered J78 (50, 100 mg/kg) dose dependently protected mice against the collagen + epinephrine-induced thromboembolic death. Orally administered J78 also significantly inhibited the ADP- and collagen-induced rat platelet aggregation ex vivo, with inhibition values of 44 and 40%, respectively. J78 inhibited the collagen-, arachidonic acid- and thrombin-induced human platelet aggregation concentration dependently in vitro, with IC(50) values of 7.8 +/- 0.4, 10.1 +/- 0.4 and 18.4 +/- 2.0 micromol/l, respectively. It was also active in inhibiting Ca(2+) ionophore, A23187-induced platelet aggregation, suggesting that J78 may have an inhibitory effect on Ca(2+) mobilization. J78, however, did not alter coagulation parameters such as activated partial thromboplastin time and prothrombin time in human plasma. Taken together, these results suggest that J78 may be a promising antithrombotic agent, and its antithrombotic activity may be due to antiplatelet rather than anticoagulation activity.
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Affiliation(s)
- Yong-Ri Jin
- College of Pharmacy, Chungbuk National University, Cheongju, Korea
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