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Gopalakrishna R, Oh A, Hou L, Lee E, Aguilar J, Li A, Mack WJ. Flavonoid quercetin and its glucuronide and sulfate conjugates bind to 67-kDa laminin receptor and prevent neuronal cell death induced by serum starvation. Biochem Biophys Res Commun 2023; 671:116-123. [PMID: 37300941 PMCID: PMC10527810 DOI: 10.1016/j.bbrc.2023.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 06/01/2023] [Indexed: 06/12/2023]
Abstract
Quercetin, a dietary flavonoid, has been shown to protect against various neurodegenerative diseases with mechanisms largely unknown. After oral administration, quercetin is rapidly conjugated, and the aglycone is not detectable in the plasma and brain. However, its glucuronide and sulfate conjugates are present only at low nanomolar concentrations in the brain. Since quercetin and its conjugates have limited antioxidant capability at low nanomolar concentrations, it is crucial to determine whether they induce neuroprotection by binding to high-affinity receptors. Previously we found that (-)-epigallocatechin-3-gallate (EGCG), a polyphenol from green tea, induces neuroprotection by binding to the 67-kDa laminin receptor (67LR). Therefore, in this study, we determined whether quercetin and its conjugates bind 67LR to induce neuroprotection and compared their ability with EGCG. Based on the quenching of intrinsic tryptophan fluorescence of peptide G (residues 161-180 in 67LR), we found quercetin, quercetin-3-O-glucuronide, and quercetin-3-O-sulfate bind to this peptide with a high affinity comparable to EGCG. Molecular docking using the crystal structure of 37-kDa laminin receptor precursor supported the high-affinity binding of all these ligands to the site corresponding to peptide G. A pretreatment with quercetin (1-1000 nM) did not effectively protect Neuroscreen-1 cells from death induced by serum starvation. Contrarily, a pretreatment with low concentrations (1-10 nM) of quercetin conjugates better protected these cells than quercetin and EGCG. The 67LR-blocking antibody substantially prevented neuroprotection by all these agents, suggesting the role of 67LR in this process. Collectively, these studies reveal that quercetin induces neuroprotection primarily through its conjugates via high affinity binding to 67LR.
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Affiliation(s)
- Rayudu Gopalakrishna
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA.
| | - Andrew Oh
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Lucas Hou
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Emily Lee
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Jennifer Aguilar
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Andrew Li
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - William J Mack
- Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
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2
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Afosah DK, Fayyad RM, Puliafico VR, Merrell S, Langmia EK, Diagne SR, Al-Horani RA, Desai UR. Homogeneous, Synthetic, Non-Saccharide Glycosaminoglycan Mimetics as Potent Inhibitors of Human Cathepsin G. Biomolecules 2023; 13:760. [PMID: 37238630 PMCID: PMC10216581 DOI: 10.3390/biom13050760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 04/25/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
Cathepsin G (CatG) is a pro-inflammatory neutrophil serine protease that is important for host defense, and has been implicated in several inflammatory disorders. Hence, inhibition of CatG holds much therapeutic potential; however, only a few inhibitors have been identified to date, and none have reached clinical trials. Of these, heparin is a well-known inhibitor of CatG, but its heterogeneity and bleeding risk reduce its clinical potential. We reasoned that synthetic small mimetics of heparin, labeled as non-saccharide glycosaminoglycan mimetics (NSGMs), would exhibit potent CatG inhibition while being devoid of bleeding risks associated with heparin. Hence, we screened a focused library of 30 NSGMs for CatG inhibition using a chromogenic substrate hydrolysis assay and identified nano- to micro-molar inhibitors with varying levels of efficacy. Of these, a structurally-defined, octasulfated di-quercetin NSGM 25 inhibited CatG with a potency of ~50 nM. NSGM 25 binds to CatG in an allosteric site through an approximately equal contribution of ionic and nonionic forces. Octasulfated 25 exhibits no impact on human plasma clotting, suggesting minimal bleeding risk. Considering that octasulfated 25 also potently inhibits two other pro-inflammatory proteases, human neutrophil elastase and human plasmin, the current results imply the possibility of a multi-pronged anti-inflammatory approach in which these proteases are likely to simultaneously likely combat important conditions, e.g., rheumatoid arthritis, emphysema, or cystic fibrosis, with minimal bleeding risk.
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Affiliation(s)
- Daniel K. Afosah
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.M.F.)
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Rawan M. Fayyad
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.M.F.)
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Valerie R. Puliafico
- Department of Chemistry and Biochemistry, Washington and Lee University, Lexington, VA 24450, USA
| | - Spencer Merrell
- Department of Chemistry and Biochemistry, Washington and Lee University, Lexington, VA 24450, USA
| | - Eltice K. Langmia
- Department of Chemistry and Biochemistry, Washington and Lee University, Lexington, VA 24450, USA
| | - Sophie R. Diagne
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Rami A. Al-Horani
- Division of Basic Pharmaceutical Sciences, College of Pharmacy, Xavier University of Louisiana, New Orleans, LA 70125, USA
| | - Umesh R. Desai
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.M.F.)
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, 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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Kolodziejczyk-Czepas J, Czepas J. Plant-Derived Compounds and Extracts as Modulators of Plasmin Activity-A Review. Molecules 2023; 28:molecules28041677. [PMID: 36838662 PMCID: PMC9965408 DOI: 10.3390/molecules28041677] [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: 12/30/2022] [Revised: 02/03/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023] Open
Abstract
Functionality of the fibrinolytic system is based on activity of its central enzyme, plasmin, responsible for the removal of fibrin clots. Besides the hemostasis, fibrinolytic proteins are also involved in many other physiological and pathological processes, including immune response, extracellular matrix degradation, cell migration, and tissue remodeling. Both the impaired and enhanced activity of fibrinolytic proteins may result in serious physiological consequences: prothrombotic state or excessive bleeding, respectively. However, current medicine offers very few options for treating fibrinolytic disorders, particularly in the case of plasmin inhibition. Although numerous attempts have been undertaken to identify natural or to develop engineered fibrinolytic system modulators, structural similarities within serine proteases of the hemostatic system and pleiotropic activity of fibrinolytic proteins constitute a serious problem in discovering anti- or profibrinolytic agents that could precisely affect the target molecules and reduce the risk of side effects. Therefore, this review aims to present a current knowledge of various classes of natural inhibitors and stimulators of the fibrinolytic system being well-defined low-molecular plant secondary metabolites or constituents of plant extracts as well as plant peptides. This work also discusses obstacles caused by low specificity of most of natural compounds and, hence, outlines recent trends in studies aimed at finding more efficient modulators of plasmin activity, including investigation of modifications of natural pharmacophore templates.
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Affiliation(s)
- Joanna Kolodziejczyk-Czepas
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland
- Correspondence:
| | - Jan Czepas
- Department of Oncobiology and Epigenetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland
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Morla S, Desai UR. Discovery of Sulfated Small Molecule Inhibitors of Matrix Metalloproteinase-8. Biomolecules 2020; 10:biom10081166. [PMID: 32784891 PMCID: PMC7465109 DOI: 10.3390/biom10081166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 08/05/2020] [Accepted: 08/07/2020] [Indexed: 12/28/2022] Open
Abstract
Elevated matrix metalloproteinase-8 (MMP-8) activity contributes to the etiology of many diseases, including atherosclerosis, pulmonary fibrosis, and sepsis. Yet, very few small molecule inhibitors of MMP-8 have been identified. We reasoned that the synthetic non-sugar mimetics of glycosaminoglycans may inhibit MMP-8 because natural glycosaminoglycans are known to modulate the functions of various MMPs. The screening a library of 58 synthetic, sulfated mimetics consisting of a dozen scaffolds led to the identification of only two scaffolds, including sulfated benzofurans and sulfated quinazolinones, as promising inhibitors of MMP-8. Interestingly, the sulfated quinazolinones displayed full antagonism of MMP-8 and sulfated benzofuran appeared to show partial antagonism. Of the two, sulfated quinazolinones exhibited a >10-fold selectivity for MMP-8 over MMP-9, a closely related metalloproteinase. Molecular modeling suggested the plausible occupancy of the S1′ pocket on MMP-8 as the distinguishing feature of the interaction. Overall, this work provides the first proof that the sulfated mimetics of glycosaminoglycans could lead to potent, selective, and catalytic activity-tunable, small molecular inhibitors of MMP-8.
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Affiliation(s)
- Shravan Morla
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298, USA;
- Drug Discovery and Development, Institute for Structural Biology, Virginia Commonwealth University, Richmond 23219, VA, USA
| | - Umesh R. Desai
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298, USA;
- Drug Discovery and Development, Institute for Structural Biology, Virginia Commonwealth University, Richmond 23219, VA, USA
- Correspondence: ; Tel.: +804-828-7575; Fax: +804-827-3664
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Inhibitors of blood coagulation factor XIII. Anal Biochem 2020; 605:113708. [PMID: 32335064 DOI: 10.1016/j.ab.2020.113708] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 03/11/2020] [Accepted: 03/30/2020] [Indexed: 02/07/2023]
Abstract
The blood coagulation factor XIII (FXIII) plays an essential role in the stabilization of fibrin clots. This factor, belonging to the class of transglutaminases, catalyzes the final step of secondary hemostasis, i.e. the crosslinking of fibrin polymers. These crosslinks protect the clots against premature fibrinolysis. Consequently, FXIII is an interesting target for the therapeutic treatment of cardiovascular diseases. In this context, inhibitors can influence FXIII in the activation process of the enzyme itself or in its catalytic activity. To date, there is no FXIII inhibitor in medical application, but several studies have been conducted in the past. These studies provided a better understanding of FXIII and identified new lead structures for FXIII inhibitors. Next to small molecule inhibitors, the most promising candidates for the development of clinically applicable FXIII inhibitors are the peptide inhibitors tridegin and transglutaminase-inhibiting Michael acceptors (TIMAs) due to their selectivity towards activated FXIII (FXIIIa). In this review, select FXIII inhibitors and their pharmacological potential are discussed.
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7
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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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8
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Al-Horani RA, Abdelfadiel EI, Afosah DK, Morla S, Sistla JC, Mohammed B, Martin EJ, Sakagami M, Brophy DF, Desai UR. A synthetic heparin mimetic that allosterically inhibits factor XIa and reduces thrombosis in vivo without enhanced risk of bleeding. J Thromb Haemost 2019; 17:2110-2122. [PMID: 31397071 PMCID: PMC6893084 DOI: 10.1111/jth.14606] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 07/15/2019] [Accepted: 08/07/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND Human factor XIa (FXIa) is an actively pursued target for development of safer anticoagulants. Our long-standing hypothesis has been that allosterism originating from heparin-binding site(s) on coagulation enzymes is a promising approach to yield safer agents. OBJECTIVES To develop a synthetic heparin mimetic as an inhibitor of FXIa so as to reduce clot formation in vivo but not carry high bleeding risk. METHODS We employed a gamut of methods involving synthetic chemistry, biophysical biochemistry, enzyme assays, blood and plasma coagulation assays, and in vivo thrombosis models in this work. RESULTS Sulfated chiro-inositol (SCI), a non-saccharide mimetic of heparin, was synthesized in three steps in overall yields of >50%. SCI inhibited FXIa with potency of 280 nmol/L and preferentially engaged FXIa's heparin-binding site to conformationally alter its active site. SCI inhibition of FXIa could be rapidly reversed by common antidotes, such as protamine. SCI preferentially prolonged plasma clotting initiated with recalcification, rather than thromboplastin, alluding to its intrinsic pathway-based mechanism. Human blood thromboelastography indicated good ex vivo anticoagulation properties of SCI. Rat tail bleeding and maximum-dose-tolerated studies indicated that no major bleeding or toxicity concerns for SCI suggesting a potentially safer anticoagulation outcome. FeCl3 -induced arterial and thromboplastin-induced venous thrombosis model studies in the rat showed reduced thrombus formation by SCI at 250 μg/animal, which matched enoxaparin at 2500 μg/animal. CONCLUSIONS Overall, SCI is a highly promising, allosteric inhibitor of FXIa that induces potent anticoagulation in vivo. Further studies are necessary to assess SCI in animal models mimicking human clinical indications.
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Affiliation(s)
- Rami A. Al-Horani
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219
| | - Elsamani I. Abdelfadiel
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219
- Department of Biochemistry, Virginia Commonwealth University, Richmond, VA 23298
| | - Daniel K. Afosah
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219
| | - Shravan Morla
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219
| | - Jyothi C. Sistla
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219
| | - Bassem Mohammed
- Department of Pharmacotherapy and Outcomes Sciences, Virginia Commonwealth University, Richmond, VA 23298
| | - Erika J. Martin
- Department of Pharmacotherapy and Outcomes Sciences, Virginia Commonwealth University, Richmond, VA 23298
| | - Masahiro Sakagami
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298
| | - Donald F. Brophy
- Department of Pharmacotherapy and Outcomes Sciences, Virginia Commonwealth University, Richmond, VA 23298
| | - Umesh R. Desai
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298
- Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219
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Steinmetzer T, Pilgram O, Wenzel BM, Wiedemeyer SJA. Fibrinolysis Inhibitors: Potential Drugs for the Treatment and Prevention of Bleeding. J Med Chem 2019; 63:1445-1472. [PMID: 31658420 DOI: 10.1021/acs.jmedchem.9b01060] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Hyperfibrinolytic situations can lead to life-threatening bleeding, especially during cardiac surgery. The approved antifibrinolytic agents such as tranexamic acid, ε-aminocaproic acid, 4-aminomethylbenzoic acid, and aprotinin were developed in the 1960s without the structural insight of their respective targets. Crystal structures of the main antifibrinolytic targets, the lysine binding sites on plasminogen's kringle domains, and plasmin's serine protease domain greatly contributed to the structure-based drug design of novel inhibitor classes. Two series of ligands targeting the lysine binding sites have been recently described, which are more potent than the most-widely used antifibrinolytic agent, tranexamic acid. Furthermore, four types of promising active site inhibitors of plasmin have been developed: tranexamic acid conjugates targeting the S1 pocket and primed sites, substrate-analogue linear homopiperidylalanine-containing 4-amidinobenzylamide derivatives, macrocyclic inhibitors addressing nonprimed binding regions, and bicyclic 14-mer SFTI-1 analogues blocking both, primed and nonprimed binding sites of plasmin. Furthermore, several allosteric plasmin inhibitors based on heparin mimetics have been developed.
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Affiliation(s)
- Torsten Steinmetzer
- Department of Pharmacy, Institute of Pharmaceutical Chemistry , Philipps University Marburg , Marbacher Weg 6 , D-35032 Marburg , Germany
| | - Oliver Pilgram
- Department of Pharmacy, Institute of Pharmaceutical Chemistry , Philipps University Marburg , Marbacher Weg 6 , D-35032 Marburg , Germany
| | - Benjamin M Wenzel
- Department of Pharmacy, Institute of Pharmaceutical Chemistry , Philipps University Marburg , Marbacher Weg 6 , D-35032 Marburg , Germany
| | - Simon J A Wiedemeyer
- Department of Pharmacy, Institute of Pharmaceutical Chemistry , Philipps University Marburg , Marbacher Weg 6 , D-35032 Marburg , Germany
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Al-Horani RA, Clemons D, Mottamal M. The In Vitro Effects of Pentamidine Isethionate on Coagulation and Fibrinolysis. Molecules 2019; 24:E2146. [PMID: 31174390 PMCID: PMC6600542 DOI: 10.3390/molecules24112146] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 05/30/2019] [Accepted: 05/30/2019] [Indexed: 12/13/2022] Open
Abstract
Pentamidine is bis-oxybenzamidine-based antiprotozoal drug. The parenteral use of pentamidine appears to affect the processes of blood coagulation and/or fibrinolysis resulting in rare but potentially life-threatening blood clot formation. Pentamidine was also found to cause disseminated intravascular coagulation syndrome. To investigate the potential underlying molecular mechanism(s) of pentamidine's effects on coagulation and fibrinolysis, we studied its effects on clotting times in normal and deficient human plasmas. Using normal plasma, pentamidine isethionate doubled the activated partial thromboplastin time at 27.5 µM, doubled the prothrombin time at 45.7 µM, and weakly doubled the thrombin time at 158.17 µM. Using plasmas deficient of factors VIIa, IXa, XIa, or XIIa, the concentrations to double the activated partial thromboplastin time were similar to that obtained using normal plasma. Pentamidine also inhibited plasmin-mediated clot lysis with half-maximal inhibitory concentration (IC50) value of ~3.6 μM. Chromogenic substrate hydrolysis assays indicated that pentamidine inhibits factor Xa and plasmin with IC50 values of 10.4 µM and 8.4 µM, respectively. Interestingly, it did not significantly inhibit thrombin, factor XIa, factor XIIIa, neutrophil elastase, or chymotrypsin at the highest concentrations tested. Michaelis-Menten kinetics and molecular modeling studies revealed that pentamidine inhibits factor Xa and plasmin in a competitive fashion. Overall, this study provides quantitative mechanistic insights into the in vitro effects of pentamidine isethionate on coagulation and fibrinolysis via the disruption of the proteolytic activity of factor Xa and plasmin.
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Affiliation(s)
- Rami A Al-Horani
- Division of Basic Pharmaceutical Sciences, College of Pharmacy, Xavier University of Louisiana, New Orleans, LA 70125, USA.
| | - Daytriona Clemons
- Division of Basic Pharmaceutical Sciences, College of Pharmacy, Xavier University of Louisiana, New Orleans, LA 70125, USA.
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11
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Morla S, Sankaranarayanan NV, Afosah DK, Kumar M, Kummarapurugu AB, Voynow JA, Desai UR. On the Process of Discovering Leads That Target the Heparin-Binding Site of Neutrophil Elastase in the Sputum of Cystic Fibrosis Patients. J Med Chem 2019; 62:5501-5511. [PMID: 31074986 DOI: 10.1021/acs.jmedchem.9b00379] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cystic fibrosis (CF) is a disease of dysregulated salt and fluid homeostasis that results in the massive accumulation of neutrophil elastase, resulting in lung degradation and death. The current CF therapy relies on inhaled deoxyribonuclease and hypertonic saline but does not address the elastolytic degradation of the lung. We reasoned that allosteric agents targeting the heparin-binding site of neutrophil elastase would offer a therapeutic paradigm. Screening a library of 60 nonsaccharide glycosaminoglycan mimetics (NSGMs) led to the discovery of 23 hits against neutrophil elastase. To identify a lead NSGM that works in sync with the current CF-relieving agents, we developed a rigorous protocol based on fundamental computational, biochemical, mechanistic, and adverse effect studies. The lead NSGM so identified neutralized neutrophil elastase present in the sputum of CF patients in the presence of deoxyribonuclease and high-salt conditions. Our work presents the process for discovering potent, small, synthetic, allosteric, anti-CF agents, while also identifying a novel lead for further studies in animal models of CF.
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Affiliation(s)
- Shravan Morla
- Department of Medicinal Chemistry , Virginia Commonwealth University , Richmond , Virginia 23298 , United States.,Institute for Structural Biology, Drug Discovery and Development , Virginia Commonwealth University , Richmond , Virginia 23219 , United States
| | - Nehru Viji Sankaranarayanan
- Department of Medicinal Chemistry , Virginia Commonwealth University , Richmond , Virginia 23298 , United States.,Institute for Structural Biology, Drug Discovery and Development , Virginia Commonwealth University , Richmond , Virginia 23219 , United States
| | - Daniel K Afosah
- Department of Medicinal Chemistry , Virginia Commonwealth University , Richmond , Virginia 23298 , United States.,Institute for Structural Biology, Drug Discovery and Development , Virginia Commonwealth University , Richmond , Virginia 23219 , United States
| | - Megh Kumar
- Department of Medicinal Chemistry , Virginia Commonwealth University , Richmond , Virginia 23298 , United States.,Institute for Structural Biology, Drug Discovery and Development , Virginia Commonwealth University , Richmond , Virginia 23219 , United States
| | - Apparao B Kummarapurugu
- Children's Hospital of Richmond at Virginia Commonwealth University , Richmond , Virginia 23298 , United States
| | - Judith A Voynow
- Children's Hospital of Richmond at Virginia Commonwealth University , Richmond , Virginia 23298 , United States
| | - Umesh R Desai
- Department of Medicinal Chemistry , Virginia Commonwealth University , Richmond , Virginia 23298 , United States.,Institute for Structural Biology, Drug Discovery and Development , Virginia Commonwealth University , Richmond , Virginia 23219 , United States
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12
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Structural studies of plasmin inhibition. Biochem Soc Trans 2019; 47:541-557. [DOI: 10.1042/bst20180211] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/28/2019] [Accepted: 01/31/2019] [Indexed: 12/24/2022]
Abstract
Abstract
Plasminogen (Plg) is the zymogen form of the serine protease plasmin (Plm), and it plays a crucial role in fibrinolysis as well as wound healing, immunity, tissue remodeling and inflammation. Binding to the targets via the lysine-binding sites allows for Plg activation by plasminogen activators (PAs) present on the same target. Cellular uptake of fibrin degradation products leads to apoptosis, which represents one of the pathways for cross-talk between fibrinolysis and tissue remodeling. Therapeutic manipulation of Plm activity plays a vital role in the treatments of a range of diseases, whereas Plm inhibitors are used in trauma and surgeries as antifibrinolytic agents. Plm inhibitors are also used in conditions such as angioedema, menorrhagia and melasma. Here, we review the rationale for the further development of new Plm inhibitors, with a particular focus on the structural studies of the active site inhibitors of Plm. We compare the binding mode of different classes of inhibitors and comment on how it relates to their efficacy, as well as possible future developments.
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Kolodziejczyk-Czepas J, Pasiński B, Ponczek MB, Moniuszko-Szajwaj B, Kowalczyk M, Pecio Ł, Nowak P, Stochmal A. Bufadienolides from Kalanchoe daigremontiana modulate the enzymatic activity of plasmin - In vitro and in silico analyses. Int J Biol Macromol 2018; 120:1591-1600. [PMID: 30261260 DOI: 10.1016/j.ijbiomac.2018.09.143] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 09/07/2018] [Accepted: 09/23/2018] [Indexed: 01/23/2023]
Abstract
Plasmin (EC 3.4.21.7) is a key enzyme of the fibrinolytic system, responsible for the degradation of fibrin clot and maintaining blood fluidity. Hence, alterations of the fibrinolytic capacity of blood plasma may contribute to thrombotic or bleeding complications. The aim of this study was to determine effects of a bufadienolide-rich fraction, isolated from roots of Kalanchoe daigremontiana (0.05-50 μg/ml) on enzymatic properties of plasmin. Hydrolysis of a synthetic substrate S-2251 (H-D-Valyl-l-leucyl-l-lysine-p-nitroaniline dihydrochloride) by plasmin revealed that the bufadienolide-rich fraction had a diverse effect on this enzyme, dependently on the concentration range. While the lower concentrations of the examined fraction (0.05-2.5 μg/ml) significantly enhanced the amidolytic activity of plasmin, at 25-50 μg/ml concentrations, the enzyme was evidently inhibited (by about 60%). The Lineweaver-Burk plot indicated on an uncompetitive inhibition of plasmin. Inhibitory effects (up to 80%) were also found in the streptokinase-induced plasminogen activation to plasmin. Docking results suggest that only some of compounds (mostly bersaldegenin 1-acetate (10), bryotoxin (13) and hovetrichoside C (17)) were bound to plasminogen/plasmin, depending on the presence or absence of the substrate in the active site. The obtained findings suggest allosteric regulation of plasminogen activation and plasmin activity by components of the examined fraction.
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Affiliation(s)
- Joanna Kolodziejczyk-Czepas
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland.
| | - Bartłomiej Pasiński
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland
| | - Michal B Ponczek
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland
| | - Barbara Moniuszko-Szajwaj
- Department of Biochemistry, Institute of Soil Science and Plant Cultivation, State Research Institute, Czartoryskich 8, 24-100 Pulawy, Poland
| | - Mariusz Kowalczyk
- Department of Biochemistry, Institute of Soil Science and Plant Cultivation, State Research Institute, Czartoryskich 8, 24-100 Pulawy, Poland
| | - Łukasz Pecio
- Department of Biochemistry, Institute of Soil Science and Plant Cultivation, State Research Institute, Czartoryskich 8, 24-100 Pulawy, Poland
| | - Pawel Nowak
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland
| | - Anna Stochmal
- Department of Biochemistry, Institute of Soil Science and Plant Cultivation, State Research Institute, Czartoryskich 8, 24-100 Pulawy, Poland
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Maza S, Gandia-Aguado N, de Paz JL, Nieto PM. Fluorous-tag assisted synthesis of a glycosaminoglycan mimetic tetrasaccharide as a high-affinity FGF-2 and midkine ligand. Bioorg Med Chem 2018; 26:1076-1085. [DOI: 10.1016/j.bmc.2018.01.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/22/2018] [Accepted: 01/24/2018] [Indexed: 02/01/2023]
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15
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The Association of Plasminogen Activator Inhibitor Type 1 (PAI-1) Level and PAI-1 4G/5G Gene Polymorphism with the Formation and the Grade of Endometrial Cancer. Biochem Genet 2017; 55:314-321. [DOI: 10.1007/s10528-017-9796-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 03/13/2017] [Indexed: 02/06/2023]
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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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Afosah DK, Al-Horani RA, Sankaranarayanan NV, Desai UR. Potent, Selective, Allosteric Inhibition of Human Plasmin by Sulfated Non-Saccharide Glycosaminoglycan Mimetics. J Med Chem 2017; 60:641-657. [DOI: 10.1021/acs.jmedchem.6b01474] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Daniel K. Afosah
- Department of Medicinal Chemistry,
and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
| | - Rami A. Al-Horani
- Department of Medicinal Chemistry,
and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
| | - Nehru Viji Sankaranarayanan
- Department of Medicinal Chemistry,
and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
| | - Umesh R. Desai
- Department of Medicinal Chemistry,
and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia 23219, United States
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18
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Glycosaminoglycans and Their Mimetics. Molecules 2016; 22:molecules22010020. [PMID: 28029141 PMCID: PMC6155932 DOI: 10.3390/molecules22010020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 12/22/2016] [Accepted: 12/22/2016] [Indexed: 11/30/2022] Open
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19
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Plug T, Meijers JC. Stimulation of thrombin- and plasmin-mediated activation of thrombin-activatable fibrinolysis inhibitor by anionic molecules. Thromb Res 2016; 146:7-14. [DOI: 10.1016/j.thromres.2016.08.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 06/29/2016] [Accepted: 08/14/2016] [Indexed: 11/25/2022]
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20
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Al-Horani RA, Karuturi R, Lee M, Afosah DK, Desai UR. Allosteric Inhibition of Factor XIIIa. Non-Saccharide Glycosaminoglycan Mimetics, but Not Glycosaminoglycans, Exhibit Promising Inhibition Profile. PLoS One 2016; 11:e0160189. [PMID: 27467511 PMCID: PMC4965010 DOI: 10.1371/journal.pone.0160189] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 07/14/2016] [Indexed: 12/13/2022] Open
Abstract
Factor XIIIa (FXIIIa) is a transglutaminase that catalyzes the last step in the coagulation process. Orthostery is the only approach that has been exploited to design FXIIIa inhibitors. Yet, allosteric inhibition of FXIIIa is a paradigm that may offer a key advantage of controlled inhibition over orthosteric inhibition. Such an approach is likely to lead to novel FXIIIa inhibitors that do not carry bleeding risks. We reasoned that targeting a collection of basic amino acid residues distant from FXIIIa’s active site by using sulfated glycosaminoglycans (GAGs) or non-saccharide GAG mimetics (NSGMs) would lead to the discovery of the first allosteric FXIIIa inhibitors. We tested a library of 22 variably sulfated GAGs and NSGMs against human FXIIIa to discover promising hits. Interestingly, although some GAGs bound to FXIIIa better than NSGMs, no GAG displayed any inhibition. An undecasulfated quercetin analog was found to inhibit FXIIIa with reasonable potency (efficacy of 98%). Michaelis-Menten kinetic studies revealed an allosteric mechanism of inhibition. Fluorescence studies confirmed close correspondence between binding affinity and inhibition potency, as expected for an allosteric process. The inhibitor was reversible and at least 9-fold- and 26-fold selective over two GAG-binding proteins factor Xa (efficacy of 71%) and thrombin, respectively, and at least 27-fold selective over a cysteine protease papain. The inhibitor also inhibited the FXIIIa-mediated polymerization of fibrin in vitro. Overall, our work presents the proof-of-principle that FXIIIa can be allosterically modulated by sulfated non-saccharide agents much smaller than GAGs, which should enable the design of selective and safe anticoagulants.
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Affiliation(s)
- Rami A. Al-Horani
- Department of Medicinal Chemistry & Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Rajesh Karuturi
- Department of Medicinal Chemistry & Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Michael Lee
- Department of Medicinal Chemistry & Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Daniel K. Afosah
- Department of Medicinal Chemistry & Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Umesh R. Desai
- Department of Medicinal Chemistry & Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia, United States of America
- * E-mail:
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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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de Paz JL, Nieto PM. Improvement on binding of chondroitin sulfate derivatives to midkine by increasing hydrophobicity. Org Biomol Chem 2016; 14:3506-9. [DOI: 10.1039/c6ob00389c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The relative binding affinities of sulfated, fully protected chondroitin sulfate oligosaccharides for midkine are much higher than those displayed by the natural deprotected sequences.
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Affiliation(s)
- J. L. de Paz
- Glycosystems Laboratory
- Instituto de Investigaciones Químicas (IIQ)
- cicCartuja
- CSIC and Universidad de Sevilla
- 41092 Sevilla
| | - P. M. Nieto
- Glycosystems Laboratory
- Instituto de Investigaciones Químicas (IIQ)
- cicCartuja
- CSIC and Universidad de Sevilla
- 41092 Sevilla
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