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El Bouakher A, Lhoste J, Martel A, Comesse S. 2,3-Epoxyamide-alcohols in Domino Reactions: En Route to Molecular Diversity. ChemistryOpen 2024; 13:e202400115. [PMID: 38752792 DOI: 10.1002/open.202400115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Indexed: 10/12/2024] Open
Abstract
The synthesis of polycyclic γ- and δ-lactams bearing up to four contiguous fully controlled stereocenters is presented. For that purpose, we developed an original approach based on the use of 2,3-epoxyamides in domino reactions by taking advantage of the nucleophilic nitrogen atom and electrophilic epoxide. In reaction with enol ethers bearing gem bis-electrophiles on the double bond as Michael acceptors, four different reaction pathways were observed. They all started with a domino oxa-Michael/aza-Michael/epoxide opening sequence and depending on substrates engaged could be followed either by a lactonization or a hemiketalization/retro-aldol cascade. Thus, four original fully-substituted piperidine- or pyrrolidine-2-one scaffolds were selectively synthesized in good to high yields. Moreover, these polycyclic lactams were obtained in high stereo- and chemo-selectively highlighting the efficiency and molecular diversity offered by this new methodology that should offer various synthetic opportunities in the future.
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Affiliation(s)
| | - Jérôme Lhoste
- IMMM, UMR, 6283 CNRS, Le Mans Université, 72085, Le Mans, France
| | - Arnaud Martel
- IMMM, UMR, 6283 CNRS, Le Mans Université, 72085, Le Mans, France
| | - Sébastien Comesse
- Normandie Univ, UNILEHAVRE FR 3038 CNRS, URCOM, 76600, Le Havre, France
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2
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Mader L, Watt SKI, Iyer HR, Nguyen L, Kaur H, Keillor JW. The war on hTG2: warhead optimization in small molecule human tissue transglutaminase inhibitors. RSC Med Chem 2023; 14:277-298. [PMID: 36846370 PMCID: PMC9945866 DOI: 10.1039/d2md00378c] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 11/15/2022] [Indexed: 11/27/2022] Open
Abstract
Human tissue transglutaminase (hTG2) is a multifunctional enzyme with protein cross-linking and G-protein activity, both of which have been implicated in the progression of diseases such as fibrosis and cancer stem cell propagation when dysregulated, prompting the development of small molecule targeted covalent inhibitors (TCIs) possessing a crucial electrophilic 'warhead'. In recent years there have been significant advances in the library of warheads available for the design of TCIs; however, the exploration of warhead functionality in hTG2 inhibitors has remained relatively stagnant. Herein, we describe a structure-activity relationship study entailing rational design and synthesis for systematic variation of the warhead on a previously reported small molecule inhibitor scaffold, and rigorous kinetic evaluation of inhibitory efficiency, selectivity, and pharmacokinetic stability. This study reveals a strong influence on the kinetic parameters k inact and K I with even subtle variation in warhead structure, suggesting that the warhead plays a significant role in not only reactivity, but also binding affinity, which consequently extends to isozyme selectivity. Warhead structure also influences in vivo stability, which we model by measuring intrinsic reactivity with glutathione, as well as stability in hepatocytes and in whole blood, giving insight into degradation pathways and relative therapeutic potential of different functional groups. This work provides fundamental structural and reactivity information highlighting the importance of strategic warhead design for the development of potent hTG2 inhibitors.
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Affiliation(s)
- Lavleen Mader
- Department of Chemistry and Biomolecular Sciences, University of Ottawa Ottawa Ontario K1N 6N5 Canada
| | - Sarah K I Watt
- Department of Chemistry and Biomolecular Sciences, University of Ottawa Ottawa Ontario K1N 6N5 Canada
| | - Harish R Iyer
- Dalriada Drug Discovery Mississauga Ontario L5N 8G4 Canada
| | - Linh Nguyen
- Dalriada Drug Discovery Mississauga Ontario L5N 8G4 Canada
| | - Harpreet Kaur
- Dalriada Drug Discovery Mississauga Ontario L5N 8G4 Canada
| | - Jeffrey W Keillor
- Department of Chemistry and Biomolecular Sciences, University of Ottawa Ottawa Ontario K1N 6N5 Canada
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3
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Rangaswamy AMM, Navals P, Gates EWJ, Shad S, Watt SKI, Keillor JW. Structure-activity relationships of hydrophobic alkyl acrylamides as tissue transglutaminase inhibitors. RSC Med Chem 2022; 13:413-428. [PMID: 35647547 PMCID: PMC9020614 DOI: 10.1039/d1md00382h] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/25/2022] [Indexed: 01/28/2023] Open
Abstract
Tissue transglutaminase (TG2) is a multifunctional protein that plays biological roles based on its ability to catalyse protein cross-linking and to function as a non-canonical G-protein known as Ghα. The non-regulated activity of TG2 has been implicated in fibrosis, celiac disease and the survival of cancer stem cells, underpinning the therapeutic potential of cell permeable small molecule inhibitors of TG2. In the current study, we designed a small library of inhibitors to explore the importance of a terminal hydrophobic moiety, as well as the length of the tether to the irreversible acrylamide warhead. Subsequent kinetic evaluation using an in vitro activity assay provided values for the k inact and K I parameters for each of these irreversible inhibitors. The resulting structure-activity relationship (SAR) clearly indicated the affinity conferred by dansyl and adamantyl moieties, as well as the efficiency provided by the shortest warhead tether. We also provide the first direct evidence of the capability of these inhibitors to suppress the GTP binding ability of TG2, at least partially. However, it is intriguing to note that the SAR trends observed herein are opposite to those predicted by molecular modelling - namely that longer tether groups should improve binding affinity by allowing for deeper insertion of the hydrophobic moiety into a hydrophobic pocket on the enzyme. This discrepancy leads us to question whether the existing crystallographic structures of TG2 are appropriate for docking non-peptidic inhibitors. In the absence of a more relevant crystallographic structure, the data from rigorous kinetic studies, such as those provided herein, are critically important for the development of future small molecule TG2 inhibitors.
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Affiliation(s)
- Alana M. M. Rangaswamy
- Department of Chemistry and Biomolecular Sciences, University of OttawaOttawaOntario K1N 6N5Canada
| | - Pauline Navals
- Department of Chemistry and Biomolecular Sciences, University of OttawaOttawaOntario K1N 6N5Canada
| | - Eric W. J. Gates
- Department of Chemistry and Biomolecular Sciences, University of OttawaOttawaOntario K1N 6N5Canada
| | - Sammir Shad
- Department of Chemistry and Biomolecular Sciences, University of OttawaOttawaOntario K1N 6N5Canada
| | - Sarah K. I. Watt
- Department of Chemistry and Biomolecular Sciences, University of OttawaOttawaOntario K1N 6N5Canada
| | - Jeffrey W. Keillor
- Department of Chemistry and Biomolecular Sciences, University of OttawaOttawaOntario K1N 6N5Canada
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4
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Structure-activity relationships of N-terminal variants of peptidomimetic tissue transglutaminase inhibitors. Eur J Med Chem 2022; 232:114172. [DOI: 10.1016/j.ejmech.2022.114172] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/29/2022] [Accepted: 01/30/2022] [Indexed: 02/07/2023]
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5
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Keillor JW, Johnson GVW. Transglutaminase 2 as a therapeutic target for neurological conditions. Expert Opin Ther Targets 2021; 25:721-731. [PMID: 34607527 DOI: 10.1080/14728222.2021.1989410] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 10/01/2021] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Transglutaminase 2 (TG2) has been implicated in numerous neurological conditions, including neurodegenerative diseases, multiple sclerosis, and CNS injury. Early studies on the role of TG2 in neurodegenerative conditions focused on its ability to 'crosslink' proteins into insoluble aggregates. However, more recent studies have suggested that this is unlikely to be the primary mechanism by which TG2 contributes to the pathogenic processes. Although the specific mechanisms by which TG2 is involved in neurological conditions have not been clearly defined, TG2 regulates numerous cellular processes through which it could contribute to a specific disease. Given the fact that TG2 is a stress-induced gene and elevated in disease or injury conditions, TG2 inhibitors may be useful neurotherapeutics. AREAS COVERED Overview of TG2 and different TG2 inhibitors. A brief review of TG2 in neurodegenerative diseases, multiple sclerosis and CNS injury and inhibitors that have been tested in different models. Database search: https://pubmed.ncbi.nlm.nih.gov prior to 1 July 2021. EXPERT OPINION Currently, it appears unlikely that inhibiting TG2 in the context of neurodegenerative diseases would be therapeutically advantageous. However, for multiple sclerosis and CNS injuries, TG2 inhibitors may have the potential to be therapeutically useful and thus there is rationale for their further development.
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Affiliation(s)
- Jeffrey W Keillor
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Gail V W Johnson
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, Rochester, NY, USA
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6
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Zhang Y, Simpson BK. Food-related transglutaminase obtained from fish/shellfish. Crit Rev Food Sci Nutr 2019; 60:3214-3232. [DOI: 10.1080/10408398.2019.1681357] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Yi Zhang
- Department of Food Science and Agricultural Chemistry, McGill University, Québec, Québec, Canada
| | - Benjamin K. Simpson
- Department of Food Science and Agricultural Chemistry, McGill University, Québec, Québec, Canada
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7
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8
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Akbar A, McNeil NMR, Albert MR, Ta V, Adhikary G, Bourgeois K, Eckert RL, Keillor JW. Structure-Activity Relationships of Potent, Targeted Covalent Inhibitors That Abolish Both the Transamidation and GTP Binding Activities of Human Tissue Transglutaminase. J Med Chem 2017; 60:7910-7927. [PMID: 28858494 DOI: 10.1021/acs.jmedchem.7b01070] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Human tissue transglutaminase (hTG2) is a multifunctional enzyme. It is primarily known for its calcium-dependent transamidation activity that leads to formation of an isopeptide bond between glutamine and lysine residues found on the surface of proteins, but it is also a GTP binding protein. Overexpression and unregulated hTG2 activity have been associated with numerous human diseases, including cancer stem cell survival and metastatic phenotype. Herein, we present a series of targeted covalent inhibitors (TCIs) based on our previously reported Cbz-Lys scaffold. From this structure-activity relationship (SAR) study, novel irreversible inhibitors were identified that block the transamidation activity of hTG2 and allosterically abolish its GTP binding ability with a high degree of selectivity and efficiency (kinact/KI > 105 M-1 min-1). One optimized inhibitor (VA4) was also shown to inhibit epidermal cancer stem cell invasion with an EC50 of 3.9 μM, representing a significant improvement over our previously reported "hit" NC9.
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Affiliation(s)
- Abdullah Akbar
- Department of Chemistry and Biomolecular Sciences, University of Ottawa , 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Nicole M R McNeil
- Department of Chemistry and Biomolecular Sciences, University of Ottawa , 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Marie R Albert
- Department of Chemistry and Biomolecular Sciences, University of Ottawa , 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Viviane Ta
- Department of Chemistry and Biomolecular Sciences, University of Ottawa , 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Gautam Adhikary
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine , Baltimore, Maryland 21201, United States
| | - Karine Bourgeois
- Department of Chemistry and Biomolecular Sciences, University of Ottawa , 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Richard L Eckert
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine , Baltimore, Maryland 21201, United States
| | - Jeffrey W Keillor
- Department of Chemistry and Biomolecular Sciences, University of Ottawa , 10 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada
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9
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Szondy Z, Korponay-Szabó I, Király R, Sarang Z, Tsay GJ. Transglutaminase 2 in human diseases. Biomedicine (Taipei) 2017; 7:15. [PMID: 28840829 PMCID: PMC5571667 DOI: 10.1051/bmdcn/2017070315] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 05/15/2017] [Indexed: 12/30/2022] Open
Abstract
Transglutaminase 2 (TG2) is an inducible transamidating acyltransferase that catalyzes Ca(2+)-dependent protein modifications. In addition to being an enzyme, TG2 also serves as a G protein for several seven transmembrane receptors and acts as a co-receptor for integrin β1 and β3 integrins distinguishing it from other members of the transglutaminase family. TG2 is ubiquitously expressed in almost all cell types and all cell compartments, and is also present on the cell surface and gets secreted to the extracellular matrix via non-classical mechanisms. TG2 has been associated with various human diseases including inflammation, cancer, fibrosis, cardiovascular disease, neurodegenerative diseases, celiac disease in which it plays either a protective role, or contributes to the pathogenesis. Thus modulating the biological activities of TG2 in these diseases will have a therapeutic value.
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Affiliation(s)
- Zsuzsa Szondy
- Dental Biochemistry, Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen 4010, Hungary
| | - Ilma Korponay-Szabó
- Department of Pediatrics and Biochemistry and Molecular Biology, University of Debrecen, Debrecen 4010, Hungary - Celiac Disease Center, Heim Pál Children's Hospital, Budapest 1089, Hungary
| | - Robert Király
- Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen 4010, Hungary
| | - Zsolt Sarang
- Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen 4010, Hungary
| | - Gregory J Tsay
- Division of Immunology and Rheumatology, Department of Internal Medicine, China Medical University Hospital, Taichung 404, Taiwan - School of medicine, College of Medicine, China Medical University, Taichung 404, Taiwan
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Agarwal S, Kovilam O, Zach TL, Agrawal DK. Immunopathogenesis and therapeutic approaches in pediatric celiac disease. Expert Rev Clin Immunol 2016; 12:857-69. [PMID: 26999328 PMCID: PMC4975578 DOI: 10.1586/1744666x.2016.1168294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 03/16/2016] [Indexed: 01/06/2023]
Abstract
Celiac Disease is an autoimmune enteropathy with increasing incidence worldwide in both adults and children. It occurs as an inflammatory condition with destruction of the normal architecture of villi on consumption of gluten and related protein products found in wheat, barley and rye. However, the exact pathogenesis is not yet fully understood. A gluten-free diet remains the main modality of therapy to date. While some patients continue to have symptoms even on a gluten-free diet, adherence to this diet is also difficult, especially for the children. Hence, there is continued interest in novel methods of therapy and the current research focus is on the promising novel non-dietary modalities of treatment. Here, we critically reviewed the existing literature regarding the pathogenesis of celiac disease in children including the role of in-utero exposure leading to neonatal and infant sensitization and its application for the development of new therapeutic approaches for these patients.
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Affiliation(s)
- Shreya Agarwal
- Department of Clinical & Translational Science, Creighton University School of Medicine, Omaha, NE, USA
| | - Oormila Kovilam
- Department of Obstetrics and Gynecology, Creighton University School of Medicine, Omaha, NE, USA
| | - Terence L. Zach
- Department of Pediatrics, Creighton University School of Medicine, Omaha, NE, USA
| | - Devendra K. Agrawal
- Department of Clinical & Translational Science, Creighton University School of Medicine, Omaha, NE, USA
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11
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Plugis NM, Khosla C. Therapeutic approaches for celiac disease. Best Pract Res Clin Gastroenterol 2015; 29:503-21. [PMID: 26060114 PMCID: PMC4465084 DOI: 10.1016/j.bpg.2015.04.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 04/23/2015] [Accepted: 04/26/2015] [Indexed: 02/06/2023]
Abstract
Celiac disease is a common, lifelong autoimmune disorder for which dietary control is the only accepted form of therapy. A strict gluten-free diet is burdensome to patients and can be limited in efficacy, indicating there is an unmet need for novel therapeutic approaches to supplement or supplant dietary therapy. Many molecular events required for disease pathogenesis have been recently characterized and inspire most current and emerging drug-discovery efforts. Genome-wide association studies (GWAS) confirm the importance of human leukocyte antigen genes in our pathogenic model and identify a number of new risk loci in this complex disease. Here, we review the status of both emerging and potential therapeutic strategies in the context of disease pathophysiology. We conclude with a discussion of how genes identified during GWAS and follow-up studies that enhance susceptibility may offer insight into developing novel therapies.
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12
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Inhibitors of tissue transglutaminase. Trends Pharmacol Sci 2014; 36:32-40. [PMID: 25500711 DOI: 10.1016/j.tips.2014.10.014] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 10/23/2014] [Accepted: 10/30/2014] [Indexed: 02/07/2023]
Abstract
Tissue transglutaminase (TG2) catalyzes the cross-linking of proteins by the formation of isopeptide bonds between glutamine (Gln) and lysine (Lys) side chains. Although TG2 is essential for the stabilization of the extracellular matrix, its unregulated activity has been implicated in celiac disease, fibrosis, and cancer metastasis, among other disorders. Given the importance and range of TG2-related pathologies, recent work has focused on the development of potent and selective inhibitors against TG2. In this review, we present the latest and most noteworthy irreversible and reversible inhibitors of TG2, and offer perspectives for the design of future inhibitors, in the hope that lead compounds with therapeutic potential may soon be discovered.
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13
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Hassan K, A-Kader H. Celiac disease: the search for adjunctive or alternative therapies. Expert Rev Gastroenterol Hepatol 2014; 8:313-21. [PMID: 24490653 DOI: 10.1586/17474124.2014.882769] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Celiac disease is a widespread disorder caused by intolerance to gluten, a common protein in food. Currently, a life-long gluten-free diet is the only available treatment for patients with celiac disease. However, adherence to gluten-free diet is difficult due to the widespread use of wheat-derived gluten in the food industry. Therefore, there is a pressing need for the development of novel non-dietary therapies. In this article, we will review several promising strategies focusing on reducing gluten immunogenicity or sequestering to gluten prevent its uptake by the intestinal epithelium. Other possible treatment strategies that will be reviewed include the suppression of the adaptive immune response, permeability modulation and the use of systemic T-cell or cytokine blockers.
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Affiliation(s)
- Kareem Hassan
- Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, The University of Arizona, Tucson AZ, USA
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14
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Imidazolium-based warheads strongly influence activity of water-soluble peptidic transglutaminase inhibitors. Eur J Med Chem 2013; 66:526-30. [PMID: 23835447 DOI: 10.1016/j.ejmech.2013.05.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2012] [Revised: 05/10/2013] [Accepted: 05/16/2013] [Indexed: 11/24/2022]
Abstract
New peptidic water-soluble inhibitors are reported. In addition to the carboxylate moiety, a new polar warhead was explored. Depending on the size of its substituents, the newly appended imidazolium scaffold designed to enhance the hydrophilic character of the inhibitors could induce a good inhibition for tissue transglutaminase (TG2) and blood coagulation factor XIIIa (FXIIIa). Correlated with the narrow tunnel that hosts the target catalytic cysteine residue, the various modulations suggest a bent conformation of the ligands as the binding pattern mode. Analogues in the dialkylsulfonium series were also tested and showed specificity for TG2 over FXIIIa.
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15
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Transglutaminase 2: biology, relevance to neurodegenerative diseases and therapeutic implications. Pharmacol Ther 2011; 133:392-410. [PMID: 22212614 DOI: 10.1016/j.pharmthera.2011.12.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 12/06/2011] [Indexed: 12/24/2022]
Abstract
Neurodegenerative disorders are characterized by progressive neuronal loss and the aggregation of disease-specific pathogenic proteins in hallmark neuropathologic lesions. Many of these proteins, including amyloid Αβ, tau, α-synuclein and huntingtin, are cross-linked by the enzymatic activity of transglutaminase 2 (TG2). Additionally, the expression and activity of TG2 is increased in affected brain regions in these disorders. These observations along with experimental evidence in cellular and mouse models suggest that TG2 can contribute to the abnormal aggregation of disease causing proteins and consequently to neuronal damage. This accumulating evidence has provided the impetus to develop inhibitors of TG2 as possible neuroprotective agents. However, TG2 has other enzymatic activities in addition to its cross-linking function and can modulate multiple cellular processes including apoptosis, autophagy, energy production, synaptic function, signal transduction and transcription regulation. These diverse properties must be taken into consideration in designing TG2 inhibitors. In this review, we discuss the biochemistry of TG2, its various physiologic functions and our current understanding about its role in degenerative diseases of the brain. We also describe the different approaches to designing TG2 inhibitors that could be developed as potential disease-modifying therapies.
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16
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Badarau E, Collighan RJ, Griffin M. Recent advances in the development of tissue transglutaminase (TG2) inhibitors. Amino Acids 2011; 44:119-27. [PMID: 22160259 DOI: 10.1007/s00726-011-1188-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2011] [Accepted: 11/29/2011] [Indexed: 01/04/2023]
Abstract
Tissue transglutaminase (TG2) is a Ca(2+)-dependent enzyme and probably the most ubiquitously expressed member of the mammalian transglutaminase family. TG2 plays a number of important roles in a variety of biological processes. Via its transamidating function, it is responsible for the cross-linking of proteins by forming isopeptide bonds between glutamine and lysine residues. Intracellularly, Ca(2+) activation of the enzyme is normally tightly regulated by the binding of GTP. However, upregulated levels of TG2 are associated with many disease states like celiac sprue, certain types of cancer, fibrosis, cystic fibrosis, multiple sclerosis, Alzheimer's, Huntington's and Parkinson's disease. Selective inhibitors for TG2 both cell penetrating and non-cell penetrating would therefore serve as novel therapeutic tools for the treatment of these disease states. Moreover, they would provide useful tools to fully elucidate the cellular mechanisms TG2 is involved in and help comprehend how the enzyme is regulated at the cellular level. The current paper is intended to give an update on the recently discovered classes of TG2 inhibitors along with their structure-activity relationships. The biological properties of these derivatives, in terms of both activity and selectivity, will also be reported in order to translate their potential for future therapeutic developments.
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Affiliation(s)
- E Badarau
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
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17
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Keillor JW, Chabot N, Roy I, Mulani A, Leogane O, Pardin C. Irreversible inhibitors of tissue transglutaminase. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2011; 78:415-47. [PMID: 22220480 DOI: 10.1002/9781118105771.ch10] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Jeffrey W Keillor
- Department of Chemistry, University of Montréal, Montréal, QC, Canada
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18
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Bergamini CM, Collighan RJ, Wang Z, Griffin M. Structure and regulation of type 2 transglutaminase in relation to its physiological functions and pathological roles. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2011; 78:1-46. [PMID: 22220471 DOI: 10.1002/9781118105771.ch1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Carlo M Bergamini
- Deparment of Biochemistry and Molecular Biology, University of Ferrara, Italy
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Abstract
Coeliac disease is a widespread, lifelong disorder for which dietary control represents the only accepted form of therapy. There is an unmet need for nondietary therapies to treat this condition. Most ongoing and emerging drug-discovery programmes are based on the understanding that coeliac disease is caused by an inappropriate T-cell-mediated immune response to dietary gluten proteins. Recent genome-wide association studies lend further support to this pathogenic model. The central role of human leucocyte antigen genes has been validated, and a number of new risk loci have been identified, most of which are related to the biology of T cells and antigen-presenting cells. Here, we review the status of potential nondietary therapies under consideration for coeliac disease. We conclude that future development of novel therapies will be aided considerably by the identification of new, preferably noninvasive, surrogate markers for coeliac disease activity.
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Affiliation(s)
- L M Sollid
- Centre for Immune Regulation, Institute of Immunology, University of Oslo and Oslo University Hospital, Oslo, Norway.
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20
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Chabot N, Moreau S, Mulani A, Moreau P, Keillor JW. Fluorescent probes of tissue transglutaminase reveal its association with arterial stiffening. ACTA ACUST UNITED AC 2011; 17:1143-50. [PMID: 21035737 DOI: 10.1016/j.chembiol.2010.06.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 06/28/2010] [Accepted: 06/30/2010] [Indexed: 10/18/2022]
Abstract
Tissue transglutaminase (TG2) catalyzes the crosslinking of proteins. TG2 has been implicated in fibrosis and vascular calcification, both of which lead to a common feature of aging known as arterial stiffness. In order to probe the role of TG2 in arterial rigidification, we have prepared a fluorescent irreversible inhibitor as a probe for TG2 activity (RhodB-PGG-K(Acr)-LPF-OH). This probe was synthesized on solid support, characterized kinetically (k(inact) = 0.68 min⁻¹, K(I) = 79 μM), and then used to stain the aorta from rats used as a model of isolated systolic hypertension (ISH). Interestingly, TG2 activity was thus shown to increase over 4 weeks of the hypertension model, corresponding with the previously observed increase in arterial stiffness. These results clearly suggest an association between TG2 and the phenomenon of arterial rigidification.
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Affiliation(s)
- Nicolas Chabot
- Département de Chimie, Université de Montréal, C.P. 6128, Succursale Centre-ville, Montréal, QC H3C3J7, Canada
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Al-Jallad HF, Myneni VD, Piercy-Kotb SA, Chabot N, Mulani A, Keillor JW, Kaartinen MT. Plasma membrane factor XIIIA transglutaminase activity regulates osteoblast matrix secretion and deposition by affecting microtubule dynamics. PLoS One 2011; 6:e15893. [PMID: 21283799 PMCID: PMC3024320 DOI: 10.1371/journal.pone.0015893] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 11/30/2010] [Indexed: 11/19/2022] Open
Abstract
Transglutaminase activity, arising potentially from transglutaminase 2 (TG2) and
Factor XIIIA (FXIIIA), has been linked to osteoblast differentiation where it is
required for type I collagen and fibronectin matrix deposition. In this study we
have used an irreversible TG-inhibitor to ‘block –and-track’
enzyme(s) targeted during osteoblast differentiation. We show that the
irreversible TG-inhibitor is highly potent in inhibiting osteoblast
differentiation and mineralization and reduces secretion of both fibronectin and
type I collagen and their release from the cell surface. Tracking of the dansyl
probe by Western blotting and immunofluorescence microscopy demonstrated that
the inhibitor targets plasma membrane-associated FXIIIA. TG2 appears not to
contribute to crosslinking activity on the osteoblast surface. Inhibition of
FXIIIA with NC9 resulted in defective secretory vesicle delivery to the plasma
membrane which was attributable to a disorganized microtubule network and
decreased microtubule association with the plasma membrane. NC9 inhibition of
FXIIIA resulted in destabilization of microtubules as assessed by cellular
Glu-tubulin levels. Furthermore, NC9 blocked modification of Glu-tubulin into
150 kDa high-molecular weight Glu-tubulin form which was specifically localized
to the plasma membrane. FXIIIA enzyme and its crosslinking activity were
colocalized with plasma membrane-associated tubulin, and thus, it appears that
FXIIIA crosslinking activity is directed towards stabilizing the interaction of
microtubules with the plasma membrane. Our work provides the first mechanistic
cues as to how transglutaminase activity could affect protein secretion and
matrix deposition in osteoblasts and suggests a novel function for plasma
membrane FXIIIA in microtubule dynamics.
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Affiliation(s)
- Hadil F. Al-Jallad
- Division of Biomedical Sciences, Faculty of Dentistry, McGill University,
Montreal, Quebec, Canada
| | - Vamsee D. Myneni
- Division of Biomedical Sciences, Faculty of Dentistry, McGill University,
Montreal, Quebec, Canada
| | - Sarah A. Piercy-Kotb
- Division of Biomedical Sciences, Faculty of Dentistry, McGill University,
Montreal, Quebec, Canada
- Division of Experimental Medicine, Department of Medicine, Faculty of
Medicine, McGill University, Montreal, Quebec, Canada
| | - Nicolas Chabot
- Department of Chemistry, Faculty of Arts and Science, Université
de Montréal, Montreal, Quebec, Canada
| | - Amina Mulani
- Department of Chemistry, Faculty of Arts and Science, Université
de Montréal, Montreal, Quebec, Canada
| | - Jeffrey W. Keillor
- Department of Chemistry, Faculty of Arts and Science, Université
de Montréal, Montreal, Quebec, Canada
| | - Mari T. Kaartinen
- Division of Biomedical Sciences, Faculty of Dentistry, McGill University,
Montreal, Quebec, Canada
- Division of Experimental Medicine, Department of Medicine, Faculty of
Medicine, McGill University, Montreal, Quebec, Canada
- * E-mail:
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22
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Schuppan D, Junker Y, Barisani D. Celiac disease: from pathogenesis to novel therapies. Gastroenterology 2009; 137:1912-33. [PMID: 19766641 DOI: 10.1053/j.gastro.2009.09.008] [Citation(s) in RCA: 409] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Revised: 09/02/2009] [Accepted: 09/11/2009] [Indexed: 02/08/2023]
Abstract
Celiac disease has become one of the best-understood HLA-linked disorders. Although it shares many immunologic features with inflammatory bowel disease, celiac disease is uniquely characterized by (1) a defined trigger (gluten proteins from wheat and related cereals), (2) the necessary presence of HLA-DQ2 or HLA-DQ8, and (3) the generation of circulating autoantibodies to the enzyme tissue transglutaminase (TG2). TG2 deamidates certain gluten peptides, increasing their affinity to HLA-DQ2 or HLA-DQ8. This generates a more vigorous CD4(+) T-helper 1 T-cell activation, which can result in intestinal mucosal inflammation, malabsorption, and numerous secondary symptoms and autoimmune diseases. Moreover, gluten elicits innate immune responses that act in concert with the adaptive immunity. Exclusion of gluten from the diet reverses many disease manifestations but is usually not or less efficient in patients with refractory celiac disease or associated autoimmune diseases. Based on the advanced understanding of the pathogenesis of celiac disease, targeted nondietary therapies have been devised, and some of these are already in phase 1 or 2 clinical trials. Examples are modified flours that have been depleted of immunogenic gluten epitopes, degradation of immunodominant gliadin peptides that resist intestinal proteases by exogenous endopeptidases, decrease of intestinal permeability by blockage of the epithelial ZOT receptor, inhibition of intestinal TG2 activity by transglutaminase inhibitors, inhibition of gluten peptide presentation by HLA-DQ2 antagonists, modulation or inhibition of proinflammatory cytokines, and induction of oral tolerance to gluten. These and other experimental therapies will be discussed critically.
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Affiliation(s)
- Detlef Schuppan
- Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA.
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23
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Elli L, Bergamini CM, Bardella MT, Schuppan D. Transglutaminases in inflammation and fibrosis of the gastrointestinal tract and the liver. Dig Liver Dis 2009; 41:541-50. [PMID: 19195940 DOI: 10.1016/j.dld.2008.12.095] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 11/28/2008] [Accepted: 12/02/2008] [Indexed: 12/11/2022]
Abstract
Transglutaminases are a family of eight currently known calcium-dependent enzymes that catalyze the cross-linking or deamidation of proteins. They are involved in important biological processes such as wound healing, tissue repair, fibrogenesis, apoptosis, inflammation and cell-cycle control. Therefore, they play important roles in the pathomechanisms of autoimmune, inflammatory and degenerative diseases, many of which affect the gastrointestinal system. Transglutaminase 2 is prominent, since it is central to the pathogenesis of celiac disease, and modulates inflammation and fibrosis in inflammatory bowel and chronic liver diseases. This review highlights our present understanding of transglutaminase function in gastrointestinal and liver diseases and therapeutic strategies that target transglutaminase activities.
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Affiliation(s)
- L Elli
- Center for Prevention and Diagnosis of Celiac Disease, Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, via F. Sforza, Milan, Italy.
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24
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25
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Jeitner TM, Muma NA, Battaile KP, Cooper AJ. Transglutaminase activation in neurodegenerative diseases. FUTURE NEUROLOGY 2009; 4:449-467. [PMID: 20161049 DOI: 10.2217/fnl.09.17] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The following review examines the role of calcium in promoting the in vitro and in vivo activation of transglutaminases in neurodegenerative disorders. Diseases such as Alzheimer's disease, Parkinson's disease and Huntington's disease exhibit increased transglutaminase activity and rises in intracellular calcium concentrations, which may be related. The aberrant activation of transglutaminase by calcium is thought to give rise to a variety of pathological moieties in these diseases, and the inhibition has been shown to have therapeutic benefit in animal and cellular models of neurodegeneration. Given the potential clinical relevance of transglutaminase inhibitors, we have also reviewed the recent development of such compounds.
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Affiliation(s)
- Thomas M Jeitner
- Applied Bench Core, Winthrop University Hospital, 222 Station Plaza North, Suite 502, Mineola, NY 11501, USA Tel.: +1 516 663 3455
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26
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Pardin C, Roy I, Chica RA, Bonneil E, Thibault P, Lubell WD, Pelletier JN, Keillor JW. Photolabeling of tissue transglutaminase reveals the binding mode of potent cinnamoyl inhibitors. Biochemistry 2009; 48:3346-53. [PMID: 19271761 DOI: 10.1021/bi802021c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have recently developed a new class of cinnamoyl derivatives as potent tissue transglutaminase (TG2) inhibitors. Herein, we report the synthesis of a diazirine derivative of these inhibitors and its application to the photolabeling of its binding site on guinea pig liver transglutaminase. Two novel homology models were generated for this commonly studied TG2, which differ in the conformational state they represent. Tryptic digest and mass spectrometric analysis of the photolabeling experiment showed that only residue Cys230 was labeled, and our homology models were used to visualize these results. This visualization suggested that Cys230 is somewhat more solvent-exposed in the "closed" conformation of TG2, compared to the "open" conformation. Docking experiments suggested binding modes consistent with the labeling pattern that would block access to the tunnel leading to the active site, consistent with the observed mode of inhibition. However, while these modeling simulations favored the closed conformation as the target of our cinnamoyl inhibitors, native PAGE experiments indicated the open conformation of the enzyme in fact predominates in the presence of our photolabeling derivative. These results are important for understanding the binding modes of TG2 inhibitors in general and will be critical for the structure-based design of future inhibitors.
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27
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Synthesis of potent water-soluble tissue transglutaminase inhibitors. Bioorg Med Chem Lett 2008; 18:5559-62. [PMID: 18812257 DOI: 10.1016/j.bmcl.2008.09.006] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2008] [Revised: 08/29/2008] [Accepted: 09/03/2008] [Indexed: 11/21/2022]
Abstract
Dipeptide-based sulfonium peptidylmethylketones derived from 6-diazo-5-oxo-L-norleucine (DON) have been investigated as potential water-soluble inhibitors of extracellular transglutaminase. The lead compounds were prepared in four steps and exhibited potent activity against tissue transglutaminase.
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28
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Pardin C, Roy I, Lubell WD, Keillor JW. Reversible and competitive cinnamoyl triazole inhibitors of tissue transglutaminase. Chem Biol Drug Des 2008; 72:189-96. [PMID: 18715232 DOI: 10.1111/j.1747-0285.2008.00696.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A series of 15 cinnamoyl triazole derivatives was prepared by Cu(I)-catalyzed azide/alkyne [3+2]-cycloaddition reactions and examined as inhibitors of guinea-pig liver transglutaminase. Several compounds exhibited activity as reversible inhibitors that were competitive with acyl donor transglutaminase substrates. For example, triazole 4d has a K(i) value of 174 nM and represents one of the most potent reversible transglutaminase inhibitors reported to date.
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Affiliation(s)
- Christophe Pardin
- Département de chimie, Université de Montréal, C.P. 6128, Succursale centre-ville, Montréal, QC H3C 3J7, Canada
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29
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Keillor JW, Chica RA, Chabot N, Vinci V, Pardin C, Fortin E, Gillet SM, Nakano Y, Kaartinen MT, Pelletier JN, Lubell WD. The bioorganic chemistry of transglutaminase — from mechanism to inhibition and engineering. CAN J CHEM 2008. [DOI: 10.1139/v08-024] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Through a multidisciplinary approach comprising organic synthesis, molecular biology, and physical organic kinetic studies, we have studied the mechanism of transglutaminase-mediated transamidation. More recently, we have applied our understanding of the mechanism to the design of reversible inhibitors and affinity labels for biological application. We have also undertaken the engineering of transglutaminase for its application as a “peptide synthase”. Herein, we present a brief overview of previously published work as well as recent results presented at the 2007 Merck–Frosst Centre for Therapeutic Research Award Lecture.Key words: transglutaminase, enzyme mechanism, enzyme inhibition, protein engineering
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30
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Wilhelmus MMM, van Dam AM, Drukarch B. Tissue transglutaminase: a novel pharmacological target in preventing toxic protein aggregation in neurodegenerative diseases. Eur J Pharmacol 2008; 585:464-72. [PMID: 18417122 DOI: 10.1016/j.ejphar.2008.01.059] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Revised: 01/10/2008] [Accepted: 01/24/2008] [Indexed: 11/30/2022]
Abstract
Alzheimer's disease, Parkinson's disease and Huntington's disease are neurodegenerative diseases, characterized by the accumulation and deposition of neurotoxic protein aggregates. The capacity of specific proteins to self-interact and form neurotoxic aggregates seems to be a common underlying mechanism leading to pathology in these neurodegenerative diseases. This process might be initiated and/or accelerated by proteins that interact with these aggregating proteins. The transglutaminase (TG) family of proteins are calcium-dependent enzymes that catalyze the formation of covalent epsilon-(gamma-glutamyl)lysine isopeptide bonds, which can result in both intra- and intermolecular cross-links. Intramolecular cross-links might modify self-interacting proteins, and make them more prone to aggregate. In addition, intermolecular cross-links could link self-aggregating proteins and thereby initiate and/or stimulate the aggregation process. So far, increased levels and activity of tissue transglutaminase (tTG), the best characterized member of the TG family, have been observed in many neurodegenerative diseases, and the self-interacting proteins, characteristic of Alzheimer's disease, Parkinson's disease and Huntington's disease, are known substrates of tTG. Here, we focus on the role of tTG in the initiation of the aggregation process of self-interacting proteins in these diseases, and promote the notion that tTG might be an attractive novel target for treatment of neurodegenerative diseases.
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Affiliation(s)
- Micha M M Wilhelmus
- Department of Anatomy and Neurosciences VU University Medical Center, Institute for Clinical and Experimental Neurosciences (ICEN), Amsterdam, The Netherlands.
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31
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Siegel M, Khosla C. Transglutaminase 2 inhibitors and their therapeutic role in disease states. Pharmacol Ther 2007; 115:232-45. [PMID: 17582505 PMCID: PMC1975782 DOI: 10.1016/j.pharmthera.2007.05.003] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Accepted: 05/03/2007] [Indexed: 02/06/2023]
Abstract
Transglutaminase 2 (TG2) is a multi-domain, multi-functional enzyme that post-translationally modifies proteins by catalyzing the formation of intermolecular isopeptide bonds between glutamine and lysine side-chains. It plays a role in diverse biological functions, including extracellular matrix formation, integrin-mediated signaling, and signal transduction involving 7-transmembrane receptors. While some of the roles of TG2 under normal physiological conditions remain obscure, the protein is believed to participate in the pathogenesis of several unrelated diseases, including celiac sprue, neurodegenerative diseases, and certain types of cancer. A variety of small molecule and peptidomimetic inhibitors of the TG2 active site have been identified. Here, we summarize the biochemistry, biology, pharmacology and medicinal chemistry of human TG2.
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Affiliation(s)
- Matthew Siegel
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305
| | - Chaitan Khosla
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305
- Department of Chemistry, Stanford University, Stanford, CA 94305
- Department of Biochemistry, Stanford University, Stanford, CA 94305
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32
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Papeo G, Giordano P, Brasca MG, Buzzo F, Caronni D, Ciprandi F, Mongelli N, Veronesi M, Vulpetti A, Dalvit C. Polyfluorinated Amino Acids for Sensitive 19F NMR-Based Screening and Kinetic Measurements. J Am Chem Soc 2007; 129:5665-72. [PMID: 17417847 DOI: 10.1021/ja069128s] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two novel series of polyfluorinated amino acids (PFAs) were designed and synthesized according to a very short and scalable synthetic sequence. The advantages and limitations of these moieties for screening purposes are presented and discussed. The potential applications of these PFAs were tested with their incorporation into small arginine-containing peptides that represent suitable substrates for the enzyme trypsin. The enzymatic reactions were monitored by 19F NMR spectroscopy, using the 3-FABS (three fluorine atoms for biochemical screening) technique. The high sensitivity achieved with these PFAs permits a reduction in substrate concentration required for 3-FABS. This is relevant in the utilization of 3-FABS in fragment-based screening for identification of small scaffolds that bind weakly to the receptor of interest. The large dispersion of 19F isotropic chemical shifts allows the simultaneous measurement of the efficiency of the different substrates, thus identifying the best substrate for screening purposes. Furthermore, the knowledge of KM and Kcat for the different substrates allows the identification of the structural motifs responsible for the binding affinity to the receptor and those affecting the chemical steps in enzymatic catalysis. This enables the construction of suitable pharmacophores that can be used for designing nonpeptidic inhibitors with high affinity for the enzyme or molecules that mimic the transition state. The novel PFAs can also find useful application in the FAXS (fluorine chemical shift anisotropy and exchange for screening) experiment, a 19F-based competition binding assay for the detection of molecules that inhibit the interaction between two proteins.
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Affiliation(s)
- Gianluca Papeo
- Chemistry Department, Nerviano Medical Sciences, Viale Pasteur 10, 20014 Nerviano, Milano, Italy.
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33
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Watts RE, Siegel M, Khosla C. Structure-activity relationship analysis of the selective inhibition of transglutaminase 2 by dihydroisoxazoles. J Med Chem 2007; 49:7493-501. [PMID: 17149878 PMCID: PMC2526180 DOI: 10.1021/jm060839a] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Human transglutaminase 2 (TG2) is believed to play an important role in the pathogenesis of various human disorders including celiac sprue, certain neurological diseases, and some types of cancer. Selective inhibition of TG2 should therefore enable further investigation of its role in physiology and disease and may lead to effective clinical treatment. Recently we showed that certain 3-halo-4-,5-dihydroisoxazole containing compounds are selective inhibitors of human TG2 with promising pharmacological activities. Here, we present definitive evidence that this class of compounds targets the active site of human TG2. Structure-activity relationship studies have provided insights into the structural prerequisites for selectivity and have led to the discovery of an inhibitor with about 50-fold higher activity than a prototypical dihydroisoxazole inhibitor with good in vivo activity. A method for preparing enantiomerically enriched analogues was also developed. Our studies show that the 5-(S)-dihydroisoxazole is a markedly better inhibitor of human TG2 than its 5-(R) stereoisomer.
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Affiliation(s)
- R Edward Watts
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
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34
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Halim D, Caron K, Keillor JW. Synthesis and evaluation of peptidic maleimides as transglutaminase inhibitors. Bioorg Med Chem Lett 2007; 17:305-8. [PMID: 17092716 DOI: 10.1016/j.bmcl.2006.10.061] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Revised: 10/11/2006] [Accepted: 10/23/2006] [Indexed: 10/24/2022]
Abstract
A series of novel transglutaminase inhibitors was prepared, based on the scaffold of a commonly used peptide substrate and bearing an electrophilic maleimide group. These compounds were evaluated in vitro and shown to lead to irreversible inactivation of tissue transglutaminase. Comparison with inhibitors studied previously provides insight into the steric environment of the enzyme active site.
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Affiliation(s)
- Dany Halim
- Département de chimie, Université de Montréal, C.P. 6128, Succursale centre-ville, Montréal, Que., Canada H3C 3J7
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35
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Pardin C, Gillet SMFG, Keillor JW. Synthesis and evaluation of peptidic irreversible inhibitors of tissue transglutaminase. Bioorg Med Chem 2006; 14:8379-85. [PMID: 17008102 DOI: 10.1016/j.bmc.2006.09.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Revised: 08/29/2006] [Accepted: 09/07/2006] [Indexed: 11/13/2022]
Abstract
Herein we report the synthesis and the evaluation of eight novel compounds as irreversible inhibitors of transglutaminase (TGase). These compounds are based on a minimal peptidic scaffold shown previously [Chem. Biol.2005, 12, 469-475] to confer affinity for the TGase active site and bear electrophilic groups such as alpha,beta-unsaturated amide, chloroacetamide or maleimide; their general structure being Cbz-Phe-spacer-electrophile. The affinity conferred by the Cbz-Phe scaffold was determined by comparison to N-propylacrylamide and the length of the spacer was also varied to evaluate its importance. The inhibitory efficiencies (k(inact)/K(I)) of these compounds vary up to 10(5)M(-1)min(-1), among the highest reported for derivatives based on this simple Cbz-Phe peptidic scaffold.
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Affiliation(s)
- Christophe Pardin
- Département de Chimie, Université de Montréal, C.P. 6128, Succursale Centre-ville, Montréal, Que., Canada H3C 3J7
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36
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Choi K, Siegel M, Piper JL, Yuan L, Cho E, Strnad P, Omary B, Rich KM, Khosla C. Chemistry and Biology of Dihydroisoxazole Derivatives: Selective Inhibitors of Human Transglutaminase 2. ACTA ACUST UNITED AC 2005; 12:469-75. [PMID: 15850984 DOI: 10.1016/j.chembiol.2005.02.007] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2005] [Revised: 02/12/2005] [Accepted: 02/15/2005] [Indexed: 11/16/2022]
Abstract
3-halo-4,5-dihydroisoxazoles are attractive warheads for the selective inhibition of nucleophilic active sites in biological systems. A series of 3-bromo-4,5-dihydroisoxazole compounds were prepared and tested for their ability to irreversibly inhibit human transglutaminase 2 (TG2), an enzyme that plays an important role in the pathogenesis of diverse disorders including Celiac Sprue and certain types of cancers. Several compounds showed high specificity for human TG2 (k(inh)/K(I) > 2000 min(-1)M(-1)) but essentially no reactivity (k < 1 min(-1)M(-1)) toward physiological thiols such as glutathione. The pharmacokinetic and pharmacodynamic properties of a prototype dihydroisoxazole inhibitor, 1b, were evaluated; in mice the compound showed good oral bioavailability, short serum half-life and efficient TG2 inhibition in small intestinal tissue, and low toxicity. It also showed excellent synergism with N,N'-bis(2-chloroethyl)-N-nitrosourea (BCNU, carmustine) against refractory glioblastoma tumors in mice. A fluorescent dihydroisoxazole inhibitor 5 facilitated microscopic visualization of TG2 endocytosis from the extracellular surface of HCT-116 cells. Together, these findings demonstrate the promise of dihydroisoxazole compounds as probes for the biology of TG2 and its role in human disease.
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Affiliation(s)
- Kihang Choi
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
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37
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Lherbet C, Morin M, Castonguay R, Keillor JW. Synthesis of aza and oxaglutamyl-p-nitroanilide derivatives and their kinetic studies with gamma-glutamyltranspeptidase. Bioorg Med Chem Lett 2003; 13:997-1000. [PMID: 12643897 DOI: 10.1016/s0960-894x(03)00083-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A new series of L-glutamic acid p-nitroanilide analogues has been synthesized and tested as substrates and inhibitors of rat kidney gamma-glutamyltranspeptidase (GGT). Kinetic parameters (K(m) and k(cat)) were determined for each analogue and provide insight into the scope and limits of GGT catalytic efficiency.
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Affiliation(s)
- Christian Lherbet
- Département de chimie, Université de Montréal, C.P. 6128, Succursale centre-ville, Montréal, Québec, Canada H3C 3J7
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38
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Hausch F, Halttunen T, Mäki M, Khosla C. Design, synthesis, and evaluation of gluten peptide analogs as selective inhibitors of human tissue transglutaminase. CHEMISTRY & BIOLOGY 2003; 10:225-31. [PMID: 12670536 DOI: 10.1016/s1074-5521(03)00045-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Recent studies have implicated a crucial role for tissue transglutaminase (TG2) in the pathogenesis of Celiac Sprue, a disorder of the small intestine triggered in genetically susceptible individuals by dietary exposure to gluten. Proteolytically stable peptide inhibitors of human TG2 were designed containing acivicin or alternatively 6-diazo-5-oxo-norleucine (DON) as warheads. In biochemical and cell-based assays, the best of these inhibitors, Ac-PQP-(DON)-LPF-NH(2), was considerably more potent and selective than other TG2 inhibitors reported to date. Selective pharmacological inhibition of extracellular TG2 should be useful in exploring the mechanistic implications of TG2-catalyzed modification of dietary gluten, a phenomenon of considerable relevance in Celiac Sprue.
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Affiliation(s)
- Felix Hausch
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
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