1
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Oh D, Chae YJ, Teoh JY, Yim B, Yoo D, Park Y, Kim J. Detection of α-Thrombin with Platelet Glycoprotein Ibα (GP1bα) for the Development of a Coagulation Marker. ACS OMEGA 2024; 9:13418-13426. [PMID: 38524497 PMCID: PMC10956406 DOI: 10.1021/acsomega.4c00010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 02/05/2024] [Accepted: 02/21/2024] [Indexed: 03/26/2024]
Abstract
The detection of prothrombotic markers is crucial for understanding thromboembolism and assessing the effectiveness of anticoagulant drugs. α-Thrombin is a marker that plays a critical role in the coagulation cascade process. However, the detection of this enzymatic molecule was hindered by the absence of an efficient modality in the clinical environment. Previously, we reported that one α-thrombin interacts with two α-chains of glycoprotein Ib (GPIbα), i.e., multivalent protein binding (MPB), using bioresponsive hydrogel nanoparticles (nanogels) and optical microscopy. In this study, we demonstrated that GPIbα-mediated platforms led to the highly sensitive and quantitative detection of α-thrombin in various diagnostic systems. Initially, a bioresponsive nanogel-based surface plasmon resonance (nSPR) assay was developed that responds to the MPB of α-thrombin to GPIbα. The use of GPIbα for the detection of α-thrombin was further validated using the enzyme-linked immunosorbent assay, which is a gold-standard protein detection technique. Additionally, GPIbα-functionalized latex beads were developed to perform latex agglutination (LA) assays, which are widely used with hospital diagnostic instruments. Notably, the nSPR and LA assays exhibited a nearly 1000-fold improvement in sensitivity for α-thrombin detection compared to our previous optical microscopy method. The superiority of our GPIbα-mediated platforms lies in their stability for α-thrombin detection through protein-protein interactions. By contrast, assays relying on α-thrombin enzymatic activity using substrates face the challenge of a rapid decrease in postsample collection. These results suggested that the MPB of α-thrombin to GPIbα is an ideal mode for clinical α-thrombin detection, particularly in outpatient settings.
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Affiliation(s)
- Doogie Oh
- R&D
Center, Scholar Foxtrot Co. Ltd., Seoul 02796, Republic of Korea
- Department
of Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Republic
of Korea
| | - Yun Jin Chae
- R&D
Center, Scholar Foxtrot Co. Ltd., Seoul 02796, Republic of Korea
| | - Jie Ying Teoh
- Department
of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Bora Yim
- R&D
Center, Scholar Foxtrot Co. Ltd., Seoul 02796, Republic of Korea
| | - Dongwon Yoo
- Department
of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
- Center
for Nanoparticle Research, Institute for
Basic Science (IBS), Seoul 08826, Republic
of Korea
| | - Yongdoo Park
- Department
of Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Republic
of Korea
| | - Jongseong Kim
- R&D
Center, Scholar Foxtrot Co. Ltd., Seoul 02796, Republic of Korea
- Department
of Biomedical Sciences, College of Medicine, Korea University, Seoul 02841, Republic
of Korea
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2
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Kellogg GE, Cen Y, Dukat M, Ellis KC, Guo Y, Li J, May AE, Safo MK, Zhang S, Zhang Y, Desai UR. Merging cultures and disciplines to create a drug discovery ecosystem at Virginia commonwealth university: Medicinal chemistry, structural biology, molecular and behavioral pharmacology and computational chemistry. SLAS DISCOVERY : ADVANCING LIFE SCIENCES R & D 2023; 28:255-269. [PMID: 36863508 PMCID: PMC10619687 DOI: 10.1016/j.slasd.2023.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/10/2023] [Accepted: 02/21/2023] [Indexed: 03/04/2023]
Abstract
The Department of Medicinal Chemistry, together with the Institute for Structural Biology, Drug Discovery and Development, at Virginia Commonwealth University (VCU) has evolved, organically with quite a bit of bootstrapping, into a unique drug discovery ecosystem in response to the environment and culture of the university and the wider research enterprise. Each faculty member that joined the department and/or institute added a layer of expertise, technology and most importantly, innovation, that fertilized numerous collaborations within the University and with outside partners. Despite moderate institutional support with respect to a typical drug discovery enterprise, the VCU drug discovery ecosystem has built and maintained an impressive array of facilities and instrumentation for drug synthesis, drug characterization, biomolecular structural analysis and biophysical analysis, and pharmacological studies. Altogether, this ecosystem has had major impacts on numerous therapeutic areas, such as neurology, psychiatry, drugs of abuse, cancer, sickle cell disease, coagulopathy, inflammation, aging disorders and others. Novel tools and strategies for drug discovery, design and development have been developed at VCU in the last five decades; e.g., fundamental rational structure-activity relationship (SAR)-based drug design, structure-based drug design, orthosteric and allosteric drug design, design of multi-functional agents towards polypharmacy outcomes, principles on designing glycosaminoglycans as drugs, and computational tools and algorithms for quantitative SAR (QSAR) and understanding the roles of water and the hydrophobic effect.
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Affiliation(s)
- Glen E Kellogg
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA.
| | - Yana Cen
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA
| | - Malgorzata Dukat
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA
| | - Keith C Ellis
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA
| | - Youzhong Guo
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA
| | - Jiong Li
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA
| | - Aaron E May
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA
| | - Martin K Safo
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA
| | - Shijun Zhang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA
| | - Yan Zhang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA
| | - Umesh R Desai
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia, 23298-0540, USA.
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3
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Abdelfadiel E, Gunta R, Villuri BK, Afosah DK, Sankaranarayanan NV, Desai UR. Designing Smaller, Synthetic, Functional Mimetics of Sulfated Glycosaminoglycans as Allosteric Modulators of Coagulation Factors. J Med Chem 2023; 66:4503-4531. [PMID: 37001055 PMCID: PMC10108365 DOI: 10.1021/acs.jmedchem.3c00132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Indexed: 04/03/2023]
Abstract
Natural glycosaminoglycans (GAGs) are arguably the most diverse collection of natural products. Unfortunately, this bounty of structures remains untapped. Decades of research has realized only one GAG-like synthetic, small-molecule drug, fondaparinux. This represents an abysmal output because GAGs present a frontier that few medicinal chemists, and even fewer pharmaceutical companies, dare to undertake. GAGs are heterogeneous, polymeric, polydisperse, highly water soluble, synthetically challenging, too rapidly cleared, and difficult to analyze. Additionally, GAG binding to proteins is not very selective and GAG-binding sites are shallow. This Perspective attempts to transform this negative view into a much more promising one by highlighting recent advances in GAG mimetics. The Perspective focuses on the principles used in the design/discovery of drug-like, synthetic, sulfated small molecules as allosteric modulators of coagulation factors, such as antithrombin, thrombin, and factor XIa. These principles will also aid the design/discovery of sulfated agents against cancer, inflammation, and microbial infection.
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Affiliation(s)
- Elsamani
I. Abdelfadiel
- Institute
for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
| | - Rama Gunta
- Institute
for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
- Department
of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Bharath Kumar Villuri
- Institute
for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
- Department
of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Daniel K. Afosah
- Institute
for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
- Department
of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Nehru Viji Sankaranarayanan
- Institute
for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
- Department
of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Umesh R. Desai
- Institute
for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
- Department
of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
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4
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Zia A, Wu Y, Nguyen T, Wang X, Peter K, Ta HT. The choice of targets and ligands for site-specific delivery of nanomedicine to atherosclerosis. Cardiovasc Res 2021; 116:2055-2068. [PMID: 32077918 DOI: 10.1093/cvr/cvaa047] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/23/2019] [Accepted: 02/17/2020] [Indexed: 12/22/2022] Open
Abstract
As nanotechnologies advance into clinical medicine, novel methods for applying nanomedicine to cardiovascular diseases are emerging. Extensive research has been undertaken to unlock the complex pathogenesis of atherosclerosis. However, this complexity presents challenges to develop effective imaging and therapeutic modalities for early diagnosis and acute intervention. The choice of ligand-receptor system vastly influences the effectiveness of nanomedicine. This review collates current ligand-receptor systems used in targeting functionalized nanoparticles for diagnosis and treatment of atherosclerosis. Our focus is on the binding affinity and selectivity of ligand-receptor systems, as well as the relative abundance of targets throughout the development and progression of atherosclerosis. Antibody-based targeting systems are currently the most commonly researched due to their high binding affinities when compared with other ligands, such as antibody fragments, peptides, and other small molecules. However, antibodies tend to be immunogenic due to their size. Engineering antibody fragments can address this issue but will compromise their binding affinity. Peptides are promising ligands due to their synthetic flexibility and low production costs. Alongside the aforementioned binding affinity of ligands, the choice of target and its abundance throughout distinct stages of atherosclerosis and thrombosis is relevant to the intended purpose of the nanomedicine. Further studies to investigate the components of atherosclerotic plaques are required as their cellular and molecular profile shifts over time.
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Affiliation(s)
- Adil Zia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Yuao Wu
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia.,School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Woolloongabba, QLD 4102, Australia
| | - Tuan Nguyen
- School of Chemical Engineering, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Xiaowei Wang
- Baker Heart and Diabetes Institute, Melbourne, VIC 3000, Australia
| | - Karlheinz Peter
- Baker Heart and Diabetes Institute, Melbourne, VIC 3000, Australia
| | - Hang T Ta
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia.,School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Woolloongabba, QLD 4102, Australia
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5
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Agten SM, Watson EE, Ripoll‐Rozada J, Dowman LJ, Wu MCL, Alwis I, Jackson SP, Pereira PJB, Payne RJ. Potent Trivalent Inhibitors of Thrombin through Hybridization of Salivary Sulfopeptides from Hematophagous Arthropods. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202015127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Stijn M. Agten
- School of Chemistry and ARC Centre of Excellence for Innovations in Peptide and Protein Science The University of Sydney Sydney NSW 2006 Australia
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM) Maastricht University Universiteitssingel 50 6229 ER Maastricht The Netherlands
| | - Emma E. Watson
- School of Chemistry and ARC Centre of Excellence for Innovations in Peptide and Protein Science The University of Sydney Sydney NSW 2006 Australia
| | - Jorge Ripoll‐Rozada
- IBMC—Instituto de Biologia Molecular e Celular and Instituto de Investigação e Inovação em Saúde Universidade do Porto 4200-135 Porto Portugal
| | - Luke J. Dowman
- School of Chemistry and ARC Centre of Excellence for Innovations in Peptide and Protein Science The University of Sydney Sydney NSW 2006 Australia
| | - Mike C. L. Wu
- Charles Perkins Centre The University of Sydney Sydney NSW 2006 Australia
- Heart Research Institute Sydney NSW 2042 Australia
| | - Imala Alwis
- Charles Perkins Centre The University of Sydney Sydney NSW 2006 Australia
- Heart Research Institute Sydney NSW 2042 Australia
| | - Shaun P. Jackson
- Charles Perkins Centre The University of Sydney Sydney NSW 2006 Australia
- Heart Research Institute Sydney NSW 2042 Australia
| | - Pedro José Barbosa Pereira
- IBMC—Instituto de Biologia Molecular e Celular and Instituto de Investigação e Inovação em Saúde Universidade do Porto 4200-135 Porto Portugal
| | - Richard J. Payne
- School of Chemistry and ARC Centre of Excellence for Innovations in Peptide and Protein Science The University of Sydney Sydney NSW 2006 Australia
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6
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Agten SM, Watson EE, Ripoll-Rozada J, Dowman LJ, Wu MCL, Alwis I, Jackson SP, Pereira PJB, Payne RJ. Potent Trivalent Inhibitors of Thrombin through Hybridization of Salivary Sulfopeptides from Hematophagous Arthropods. Angew Chem Int Ed Engl 2021; 60:5348-5356. [PMID: 33345438 DOI: 10.1002/anie.202015127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/14/2020] [Indexed: 12/20/2022]
Abstract
Blood feeding arthropods, such as leeches, ticks, flies and mosquitoes, provide a privileged source of peptidic anticoagulant molecules. These primarily operate through inhibition of the central coagulation protease thrombin by binding to the active site and either exosite I or exosite II. Herein, we describe the rational design of a novel class of trivalent thrombin inhibitors that simultaneously block both exosites as well as the active site. These engineered hybrids were synthesized using tandem diselenide-selenoester ligation (DSL) and native chemical ligation (NCL) reactions in one-pot. The most potent trivalent inhibitors possessed femtomolar inhibition constants against α-thrombin and were selective over related coagulation proteases. A lead hybrid inhibitor possessed potent anticoagulant activity, blockade of both thrombin generation and platelet aggregation in vitro and efficacy in a murine thrombosis model at 1 mg kg-1 . The rational engineering approach described here lays the foundation for the development of potent and selective inhibitors for a range of other enzymatic targets that possess multiple sites for the disruption of protein-protein interactions, in addition to an active site.
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Affiliation(s)
- Stijn M Agten
- School of Chemistry and ARC Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Sydney, 2006, NSW, Australia
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands
| | - Emma E Watson
- School of Chemistry and ARC Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Jorge Ripoll-Rozada
- IBMC-Instituto de Biologia Molecular e Celular and Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Luke J Dowman
- School of Chemistry and ARC Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Mike C L Wu
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
- Heart Research Institute, Sydney, NSW, 2042, Australia
| | - Imala Alwis
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
- Heart Research Institute, Sydney, NSW, 2042, Australia
| | - Shaun P Jackson
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
- Heart Research Institute, Sydney, NSW, 2042, Australia
| | - Pedro José Barbosa Pereira
- IBMC-Instituto de Biologia Molecular e Celular and Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Richard J Payne
- School of Chemistry and ARC Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney, Sydney, 2006, NSW, Australia
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7
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Troisi R, Balasco N, Vitagliano L, Sica F. Molecular dynamics simulations of human α-thrombin in different structural contexts: evidence for an aptamer-guided cooperation between the two exosites. J Biomol Struct Dyn 2020; 39:2199-2209. [PMID: 32202471 DOI: 10.1080/07391102.2020.1746693] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Human α-thrombin (thrombin) is a multifunctional enzyme that plays a pivotal role in the coagulation pathway. Thrombin activity can be effectively modulated by G-quadruplex-based oligonucleotide aptamers that specifically interact with the two positively charged regions (exosites I and II) on the protein surface. Although insightful atomic-level snapshots of the recognition between thrombin and aptamers have been recently achieved through crystallographic analyses, some dynamic aspects of this interaction have not been fully characterized. We here report molecular dynamics simulations of thrombin in different association states: ligand-free and binary/ternary complexes with the aptamers TBA (at exosite I) and HD22_27mer (at exosite II). The simulations carried out on the binary and ternary complexes formed by thrombin with these aptamers provide a dynamic view of the interactions that stabilize them in a crystal-free environment. Interestingly, the analysis of the dynamics of the exosites in different thrombin binding states clearly indicates that the HD22_27mer binding at the exosite II favours conformations of exosite I that are prone to the TBA binding. Similar effects are observed upon the binding of TBA to the exosite I. These observations provide an atomic-level picture of the exosite inter-communication in thrombin and explain the experimentally detected cooperativity of the TBA/HD22_27mer binding.
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Affiliation(s)
- Romualdo Troisi
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, Naples, Italy
| | - Nicole Balasco
- Institute of Biostructures and Bioimaging, CNR, Naples, Italy
| | | | - Filomena Sica
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, Naples, Italy
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8
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Afosah DK, Al-Horani RA. Sulfated Non-Saccharide Glycosaminoglycan Mimetics as Novel Drug Discovery Platform for Various Pathologies. Curr Med Chem 2020; 27:3412-3447. [PMID: 30457046 PMCID: PMC6551317 DOI: 10.2174/0929867325666181120101147] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 11/06/2018] [Accepted: 11/13/2018] [Indexed: 01/14/2023]
Abstract
Glycosaminoglycans (GAGs) are very complex, natural anionic polysaccharides. They are polymers of repeating disaccharide units of uronic acid and hexosamine residues. Owing to their template-free, spatiotemporally-controlled, and enzyme-mediated biosyntheses, GAGs possess enormous polydispersity, heterogeneity, and structural diversity which often translate into multiple biological roles. It is well documented that GAGs contribute to physiological and pathological processes by binding to proteins including serine proteases, serpins, chemokines, growth factors, and microbial proteins. Despite advances in the GAG field, the GAG-protein interface remains largely unexploited by drug discovery programs. Thus, Non-Saccharide Glycosaminoglycan Mimetics (NSGMs) have been rationally developed as a novel class of sulfated molecules that modulate GAG-protein interface to promote various biological outcomes of substantial benefit to human health. In this review, we describe the chemical, biochemical, and pharmacological aspects of recently reported NSGMs and highlight their therapeutic potentials as structurally and mechanistically novel anti-coagulants, anti-cancer agents, anti-emphysema agents, and anti-viral agents. We also describe the challenges that complicate their advancement and describe ongoing efforts to overcome these challenges with the aim of advancing the novel platform of NSGMs to clinical use.
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Affiliation(s)
- Daniel K. Afosah
- Department of Medicinal Chemistry and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219
| | - Rami A. Al-Horani
- Division of Basic Pharmaceutical Sciences, College of Pharmacy, Xavier University of Louisiana, New Orleans, Louisiana 70125
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9
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Billur R, Sabo TM, Maurer MC. Thrombin Exosite Maturation and Ligand Binding at ABE II Help Stabilize PAR-Binding Competent Conformation at ABE I. Biochemistry 2019; 58:1048-1060. [PMID: 30672691 DOI: 10.1021/acs.biochem.8b00943] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Thrombin, derived from zymogen prothrombin (ProT), is a serine protease involved in procoagulation, anticoagulation, and platelet activation. Thrombin's actions are regulated through anion-binding exosites I and II (ABE I and ABE II) that undergo maturation during activation. Mature ABEs can utilize exosite-based communication to fulfill thrombin functions. However, the conformational basis behind such long-range communication and the resultant ligand binding affinities are not well understood. Protease activated receptors (PARs), involved in platelet activation and aggregation, are known to target thrombin ABE I. Unexpectedly, PAR3 (44-56) can already bind to pro-ABE I of ProT. Nuclear magnetic resonance (NMR) ligand-enzyme titrations were used to characterize how individual PAR1 (49-62) residues interact with pro-ABE I and mature ABE I. 1D proton line broadening studies demonstrated that binding affinities for native PAR1P (49-62, P54) and for the weak binding variant PAR1G (49-62, P54G) increased as ProT was converted to mature thrombin. 1H,15N-HSQC titrations revealed that PAR1G residues K51, E53, F55, D58, and E60 exhibited less affinity to pro-ABE I than comparable residues in PAR3G (44-56, P51G). Individual PAR1G residues then displayed tighter binding upon exosite maturation. Long-range communication between thrombin exosites was examined by saturating ABE II with phosphorylated GpIbα (269-282, 3Yp) and monitoring the binding of PAR1 and PAR3 peptides to ABE I. Individual PAR residues exhibited increased affinities in this dual-ligand environment supporting the presence of interexosite allostery. Exosite maturation and beneficial long-range allostery are proposed to help stabilize an ABE I conformation that can effectively bind PAR ligands.
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Affiliation(s)
- Ramya Billur
- Department of Chemistry , University of Louisville , Louisville , Kentucky 40292 , United States
| | - T Michael Sabo
- Department of Medicine, James Graham Brown Cancer Center , University of Louisville , Louisville , Kentucky 40202 , United States
| | - Muriel C Maurer
- Department of Chemistry , University of Louisville , Louisville , Kentucky 40292 , United States
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10
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Dong X, Gu R, Zhu X, Gan H, Liu J, Jin J, Meng Z, Dou G. Evaluating prodrug characteristics of a novel anticoagulant fusion protein neorudin, a prodrug targeting release of hirudin variant 2-Lys47 at the thrombosis site, by means of in vitro pharmacokinetics. Eur J Pharm Sci 2018; 121:166-177. [PMID: 29802897 DOI: 10.1016/j.ejps.2018.05.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Revised: 05/18/2018] [Accepted: 05/23/2018] [Indexed: 11/27/2022]
Abstract
Recombinant neorudin (EPR-hirudin, EH), a low-bleeding anticoagulant fusion protein, is an inactive prodrug designed to be converted to the active metabolite, hirudin variant 2-Lys47 (HV2), locally at the thrombus site by FXa and/or FXIa, following activation of the coagulation system. Our aim was to evaluate the prodrug characteristics of EH by comparing the biotransformation of EH and HV2 in biological matrices, including rat blood, liver, and kidney homogenates, demonstrating the cleavage of EH to HV2 by FXa and FXIa, and comparing the conversion of EH to HV2 between fresh whole blood and whole-blood clot homogenate, using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). Both EH and HV2 were stable in blood and unstable in the liver and kidney homogenates. Eight EH metabolites and eight HV2 metabolites identified as N-terminal fragments were found in the liver and kidney. C-terminal proteolysis is therefore the major metabolic pathway, with serine/cysteine carboxypeptidases and metallocarboxypeptidases being responsible for the degradation of EH and HV2 in the liver and kidney, respectively. EH was cleaved to release HV2 by FXIa. Higher levels of HV2 were produced from EH in the whole-blood clot homogenate, in which the coagulation system was activated compared with those in fresh whole blood. In conclusion, the metabolism of EH and HV2 shares the same cleavage pattern, and EH is transformed into HV2 when the coagulation system is activated, where FXIa is a specific enzyme. Our in vitro study revealed the anticipated prodrug characteristics of EH newly designed as an inactive prodrug of hirudin.
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Affiliation(s)
- Xiaona Dong
- State Key Laboratory of Drug Metabolism and Pharmacokinetics, Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, China
| | - Ruolan Gu
- State Key Laboratory of Drug Metabolism and Pharmacokinetics, Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, China
| | - Xiaoxia Zhu
- State Key Laboratory of Drug Metabolism and Pharmacokinetics, Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, China
| | - Hui Gan
- State Key Laboratory of Drug Metabolism and Pharmacokinetics, Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, China
| | | | - Jide Jin
- Laboratory of Experimental Hematology, Beijing Institute of Radiation Medicine, China
| | - Zhiyun Meng
- State Key Laboratory of Drug Metabolism and Pharmacokinetics, Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, China.
| | - Guifang Dou
- State Key Laboratory of Drug Metabolism and Pharmacokinetics, Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, China.
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11
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Billur R, Ban D, Sabo TM, Maurer MC. Deciphering Conformational Changes Associated with the Maturation of Thrombin Anion Binding Exosite I. Biochemistry 2017; 56:6343-6354. [PMID: 29111672 DOI: 10.1021/acs.biochem.7b00970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Thrombin participates in procoagulation, anticoagulation, and platelet activation. This enzyme contains anion binding exosites, ABE I and ABE II, which attract regulatory biomolecules. As prothrombin is activated to thrombin, pro-ABE I is converted into mature ABE I. Unexpectedly, certain ligands can bind to pro-ABE I specifically. Moreover, knowledge of changes in conformation and affinity that occur at the individual residue level as pro-ABE I is converted to ABE I is lacking. Such changes are transient and were not captured by crystallography. Therefore, we employed nuclear magnetic resonance (NMR) titrations to monitor development of ABE I using peptides based on protease-activated receptor 3 (PAR3). Proton line broadening NMR revealed that PAR3 (44-56) and more weakly binding PAR3G (44-56) could already interact with pro-ABE I on prothrombin. 1H-15N heteronuclear single-quantum coherence NMR titrations were then used to probe binding of individual 15N-labeled PAR3G residues (F47, E48, L52, and D54). PAR3G E48 and D54 could interact electrostatically with prothrombin and tightened upon thrombin maturation. The higher affinity for PAR3G D54 suggests the region surrounding thrombin R77a is better oriented to bind D54 than the interaction between PAR3G E48 and thrombin R75. Aromatic PAR3G F47 and aliphatic L52 both reported on significant changes in the chemical environment upon conversion of prothrombin to thrombin. The ABE I region surrounding the 30s loop was more affected than the hydrophobic pocket (F34, L65, and I82). Our NMR titrations demonstrate that PAR3 residues document structural rearrangements occurring during exosite maturation that are missed by reported X-ray crystal structures.
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Affiliation(s)
- Ramya Billur
- Department of Chemistry, University of Louisville , Louisville, Kentucky 40292, United States
| | - David Ban
- Department of Medicine, James Graham Brown Cancer Center, University of Louisville , Louisville, Kentucky 40202, United States
| | - T Michael Sabo
- Department of Medicine, James Graham Brown Cancer Center, University of Louisville , Louisville, Kentucky 40202, United States
| | - Muriel C Maurer
- Department of Chemistry, University of Louisville , Louisville, Kentucky 40292, United States
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Abstract
Antiplatelet therapy displays a critical role in the treatment and prevention of antithrombotic disorders. Many new antiplatelet agents have been developed following the emergence of various clinical limitations of classical antiplatelet drugs. This review covers mainly the recent advances in the development of P2Y12 antagonists and GPIIb/IIIa antagonists. Meanwhile, it summarizes promising approaches to new platelet surface receptors such as prostanoid EP3 receptor, thromboxane A2 prostanoid receptor, protease-activated receptors, GPIb-IX-V receptor and P-selectin. In addition, PI3Kβ, a critical protein at the inside signaling pathway of platelet activation is also mentioned as an important antiplatelet target. Moreover, the development of respective drug candidates is discussed in detail.
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13
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Chen K, Stafford AR, Wu C, Yeh CH, Kim PY, Fredenburgh JC, Weitz JI. Exosite 2-Directed Ligands Attenuate Protein C Activation by the Thrombin–Thrombomodulin Complex. Biochemistry 2017; 56:3119-3128. [DOI: 10.1021/acs.biochem.7b00250] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kai Chen
- Department of Medicine, ‡Department of Biochemistry
and Biomedical Sciences, and §Thrombosis and
Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Alan R. Stafford
- Department of Medicine, ‡Department of Biochemistry
and Biomedical Sciences, and §Thrombosis and
Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Chengliang Wu
- Department of Medicine, ‡Department of Biochemistry
and Biomedical Sciences, and §Thrombosis and
Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Calvin H. Yeh
- Department of Medicine, ‡Department of Biochemistry
and Biomedical Sciences, and §Thrombosis and
Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Paul Y. Kim
- Department of Medicine, ‡Department of Biochemistry
and Biomedical Sciences, and §Thrombosis and
Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - James C. Fredenburgh
- Department of Medicine, ‡Department of Biochemistry
and Biomedical Sciences, and §Thrombosis and
Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Jeffrey I. Weitz
- Department of Medicine, ‡Department of Biochemistry
and Biomedical Sciences, and §Thrombosis and
Atherosclerosis Research Institute, McMaster University, Hamilton, Ontario, Canada
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14
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Nagarajan B, Sankaranarayanan NV, Patel BB, Desai UR. A molecular dynamics-based algorithm for evaluating the glycosaminoglycan mimicking potential of synthetic, homogenous, sulfated small molecules. PLoS One 2017; 12:e0171619. [PMID: 28182755 PMCID: PMC5300208 DOI: 10.1371/journal.pone.0171619] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 01/23/2017] [Indexed: 01/06/2023] Open
Abstract
Glycosaminoglycans (GAGs) are key natural biopolymers that exhibit a range of biological functions including growth and differentiation. Despite this multiplicity of function, natural GAG sequences have not yielded drugs because of problems of heterogeneity and synthesis. Recently, several homogenous non-saccharide glycosaminoglycan mimetics (NSGMs) have been reported as agents displaying major therapeutic promise. Yet, it remains unclear whether sulfated NSGMs structurally mimic sulfated GAGs. To address this, we developed a three-step molecular dynamics (MD)-based algorithm to compare sulfated NSGMs with GAGs. In the first step of this algorithm, parameters related to the range of conformations sampled by the two highly sulfated molecules as free entities in water were compared. The second step compared identity of binding site geometries and the final step evaluated comparable dynamics and interactions in the protein-bound state. Using a test case of interactions with fibroblast growth factor-related proteins, we show that this three-step algorithm effectively predicts the GAG structure mimicking property of NSGMs. Specifically, we show that two unique dimeric NSGMs mimic hexameric GAG sequences in the protein-bound state. In contrast, closely related monomeric and trimeric NSGMs do not mimic GAG in either the free or bound states. These results correspond well with the functional properties of NSGMs. The results show for the first time that appropriately designed sulfated NSGMs can be good structural mimetics of GAGs and the incorporation of a MD-based strategy at the NSGM library screening stage can identify promising mimetics of targeted GAG sequences.
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Affiliation(s)
- Balaji Nagarajan
- Institute for Structural Biology, Drug Discovery and Development and Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Nehru Viji Sankaranarayanan
- Institute for Structural Biology, Drug Discovery and Development and Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Bhaumik B. Patel
- Hunter Holmes Muire VA Medical Center, Richmond, Virginia, United States of America
- Division of Hematology, Oncology, and Palliative Care, Department of Internal Medicine and Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Umesh R. Desai
- Institute for Structural Biology, Drug Discovery and Development and Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
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15
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Abstract
Thrombosis is a complex process involving multiple pathways. Currently, therapy relies on the combination of two or more antithrombotic drugs, showing that inhibiting more than one target provides benefits in the prevention and treatment of thrombosis. This review focuses on structure-activity relationship studies of molecules possessing multiple actions against thrombosis, namely, dual inhibitors of coagulation, dual inhibitors of coagulation and platelet aggregation, and also dual inhibitors of platelet aggregation. EP217609 has just entered clinical trials, which raise the expectations on the multitarget strategy to prevent or treat thrombosis.
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16
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Allosteric Partial Inhibition of Monomeric Proteases. Sulfated Coumarins Induce Regulation, not just Inhibition, of Thrombin. Sci Rep 2016; 6:24043. [PMID: 27053426 PMCID: PMC4823711 DOI: 10.1038/srep24043] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 03/14/2016] [Indexed: 11/26/2022] Open
Abstract
Allosteric partial inhibition of soluble, monomeric proteases can offer major regulatory advantages, but remains a concept on paper to date; although it has been routinely documented for receptors and oligomeric proteins. Thrombin, a key protease of the coagulation cascade, displays significant conformational plasticity, which presents an attractive opportunity to discover small molecule probes that induce sub-maximal allosteric inhibition. We synthesized a focused library of some 36 sulfated coumarins to discover two agents that display sub-maximal efficacy (~50%), high potency (<500 nM) and high selectivity for thrombin (>150-fold). Michaelis-Menten, competitive inhibition, and site-directed mutagenesis studies identified exosite 2 as the site of binding for the most potent sulfated coumarin. Stern-Volmer quenching of active site-labeled fluorophore suggested that the allosteric regulators induce intermediate structural changes in the active site as compared to those that display ~80–100% efficacy. Antithrombin inactivation of thrombin was impaired in the presence of the sulfated coumarins suggesting that allosteric partial inhibition arises from catalytic dysfunction of the active site. Overall, sulfated coumarins represent first-in-class, sub-maximal inhibitors of thrombin. The probes establish the concept of allosteric partial inhibition of soluble, monomeric proteins. This concept may lead to a new class of anticoagulants that are completely devoid of bleeding.
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Mehta AY, Mohammed BM, Martin EJ, Brophy DF, Gailani D, Desai UR. Allosterism-based simultaneous, dual anticoagulant and antiplatelet action: allosteric inhibitor targeting the glycoprotein Ibα-binding and heparin-binding site of thrombin. J Thromb Haemost 2016; 14:828-38. [PMID: 26748875 PMCID: PMC4828251 DOI: 10.1111/jth.13254] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 12/24/2015] [Indexed: 12/01/2022]
Abstract
BACKGROUND Allosteric inhibition is a promising approach for developing a new group of anticoagulants with potentially reduced bleeding consequences. Recently, we designed sulfated β-O4 lignin (SbO4L) as an allosteric inhibitor that targets exosite 2 of thrombin to reduce fibrinogen cleavage through allostery and compete with glycoprotein Ibα to reduce platelet activation. OBJECTIVE To assess: (i) the antithrombotic potential of a novel approach of simultaneous exosite 2-dependent allosteric inhibition of thrombin and competitive inhibition of platelet activation; and (ii) the promise of SbO4L as the first-in-class antithrombotic agent. METHODS A combination of whole blood thromboelastography, hemostasis analysis, mouse arterial thrombosis models and mouse tail bleeding studies were used to assess antithrombotic potential. RESULTS AND CONCLUSIONS SbO4L extended the clot initiation time, and reduced maximal clot strength, platelet contractile force, and the clot elastic modulus, suggesting dual anticoagulant and antiplatelet effects. These effects were comparable to those observed with enoxaparin. A dose of 1 mg of SbO4L per mouse prevented occlusion in 100% of arteries, and lower doses resulted in a proportionally reduced response. Likewise, the time to occlusion increased by ~ 70% with a 0.5-mg dose in the mouse Rose Bengal thrombosis model. Finally, tail bleeding studies demonstrated that SbO4L does not increase bleeding propensity. In comparison, a 0.3-mg dose of enoxaparin increased the bleeding time and blood volume loss. Overall, this study highlights the promise of the allosteric inhibition approach, and presents SbO4L as a novel anticoagulant with potentially reduced bleeding side effects.
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Affiliation(s)
- Akul Y. Mehta
- Department of Medicinal Chemistry and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Bassem M. Mohammed
- Department of Pharmacotherapy and Outcomes Science, Virginia Commonwealth University, Richmond, VA 23298, USA
- Department of Clinical Pharmacy, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt
| | - Erika J. Martin
- Department of Pharmacotherapy and Outcomes Science, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Donald F. Brophy
- Department of Pharmacotherapy and Outcomes Science, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - David Gailani
- Department of Pathology, Immunology and Microbiology, Vanderbilt University Medical Center, Nashville, TN 37203
| | - Umesh R. Desai
- Department of Medicinal Chemistry and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
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18
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He LW, Dai WC, Li NG. Development of Orally Active Thrombin Inhibitors for the Treatment of Thrombotic Disorder Diseases. Molecules 2015; 20:11046-62. [PMID: 26083038 PMCID: PMC6272601 DOI: 10.3390/molecules200611046] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 06/10/2015] [Indexed: 12/16/2022] Open
Abstract
Thrombotic disorders represent the major share of the various cardiovascular diseases, and significant progress has been made in the development of synthetic thrombin inhibitors as new anticoagulants. In addition to the development of highly potent and selective inhibitors with improved safety and suitable half-life, several allosteric inhibitors have been designed and synthesized, that did not fully nullify the procoagulant signal and thus could result in reduced bleeding complications. Furthermore, natural products with thrombin inhibitory activity have been isolated, and some natural products have been modified in order to improve their inhibitory activity and metabolic stability. This review summarizes the development of orally active thrombin inhibitors for the treatment of thrombotic disorder diseases, which could serve as a reference for the interested researchers.
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Affiliation(s)
- Li-Wei He
- Department of Medicinal Chemistry, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Wei-Chen Dai
- Department of Medicinal Chemistry, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Nian-Guang Li
- Department of Medicinal Chemistry, Nanjing University of Chinese Medicine, Nanjing 210023, China.
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Shi ZH, Li NG, Tang YP, Duan JA. Prolinamide derivatives as thrombin inhibitors for the treatment of thrombin-mediated diseases: a patent evaluation of US2013296245. Expert Opin Ther Pat 2014; 24:1139-48. [PMID: 25231888 DOI: 10.1517/13543776.2014.959493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Thrombotic disorders can lead to deep vein thrombosis, myocardial infarction and stroke. Thrombin plays a vital role in cascade reaction of blood coagulation, inhibition of the activity of thrombin can block the formation of thrombus and direct thrombin inhibitor has a prospect to overcome the limitations in application of the traditional anticoagulant drugs. AREAS COVERED The current patent US2013296245 describes a series of prolinamide derivatives with formula (I) as thrombin inhibitors. These new compounds are defined to be pharmaceutically acceptable salts derived from pharmaceutically acceptable inorganic acid and organic acid, and pharmaceutically acceptable prodrug where N-alkoxycarbonyl is protected or carboxylic acid is protected by ester. EXPERT OPINION The patent used formamidine and its N-alkoxycarbonyl-protected derivatives as the P1 group; these groups were less basic compared with the traditional guanidine group, so their lipophilicity could be optimized to achieve oral absorption. Furthermore, these pharmaceutically acceptable prodrugs where N-alkoxycarbonyl is protected or carboxylic acid is protected by ester could achieve prolonged half-life for a convenient once- or twice-daily oral dosing. These efforts gave a new hope and confidence to treat thrombotic disorders with selective and orally active thrombin inhibitors.
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Affiliation(s)
- Zhi-Hao Shi
- Nanjing University of Chinese Medicine, National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine , 138 Xianlin Road, Nanjing 210023, Jiangsu , PR China +86 25 85811916 ; +86 25 85811916 ; ,
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20
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Substantial non-electrostatic forces are needed to induce allosteric disruption of thrombin's active site through exosite 2. Biochem Biophys Res Commun 2014; 452:813-6. [PMID: 25201728 DOI: 10.1016/j.bbrc.2014.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 09/01/2014] [Indexed: 11/20/2022]
Abstract
Sulfated β-O4 lignin (SbO4L), a non-saccharide glycosaminoglycan mimetic, was recently disclosed as a novel exosite 2-directed thrombin inhibitor with the capability of mimicking sulfated tyrosine sequences of glycoprotein Ibα resulting in dual anticoagulant and antiplatelet activities. SbO4L engages essentially the same residues of exosite 2 as heparin and yet induces allosteric inhibition. Fluorescence spectroscopic studies indicate that SbO4L reduces access of the active site to molecular probes and affinity studies at varying salt concentrations show nearly 6 ionic interactions, similar to heparin, but much higher non-ionic contribution. The results suggest that subtle increase in non-electrostatic forces arising from SbO4L's aromatic scaffold appear to be critical for inducing allosteric dysfunction of thrombin's active site.
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