1
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Hoy Z, Wright TW, Elliott M, Malone J, Bhagwat S, Wang J, Gigliotti F. Combination Immunotherapy with Passive Antibody and Sulfasalazine Accelerates Fungal Clearance and Promotes the Resolution of Pneumocystis-Associated Immunopathogenesis. Infect Immun 2020; 88:e00640-19. [PMID: 31611280 PMCID: PMC6977122 DOI: 10.1128/iai.00640-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 10/10/2019] [Indexed: 12/31/2022] Open
Abstract
The pulmonary immune response protects healthy individuals against Pneumocystis pneumonia (PcP). However, the immune response also drives immunopathogenesis in patients who develop severe PcP, and it is generally accepted that optimal treatment requires combination strategies that promote fungal killing and also provide effective immunomodulation. The anti-inflammatory drug sulfasalazine programs macrophages for enhanced Pneumocystis phagocytosis and also suppresses PcP-related immunopathogenesis. Anti-Pneumocystis antibody opsonizes Pneumocystis organisms for greater phagocytosis and may also mask antigens that drive immunopathogenesis. Thus, we hypothesized that combining antibody and sulfasalazine would have the dual benefit of enhancing fungal clearance while dampening immunopathogenesis and allow the rescue of severe PcP. To model a clinically relevant treatment scenario in mice, therapeutic interventions were withheld until clear symptoms of pneumonia were evident. When administered individually, both passive antibody and sulfasalazine improved pulmonary function and enhanced Pneumocystis clearance to similar degrees. However, combination treatment with antibody and sulfasalazine produced a more rapid improvement, with recovery of body weight, a dramatic improvement in pulmonary function, reduced lung inflammation, and the rapid clearance of the Pneumocystis organisms. Accelerated fungal clearance in the combination treatment group was associated with a significant increase in macrophage phagocytosis of Pneumocystis Both passive antibody and sulfasalazine resulted in the suppression of Th1 cytokines and a marked increase in lung macrophages displaying an alternatively activated phenotype, which were enhanced by combination treatment. Our data support the concept that passive antibody and sulfasalazine could be an effective and specific adjunctive therapy for PcP, with the potential to accelerate fungal clearance while attenuating PcP-associated immunopathogenesis.
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Affiliation(s)
- Zachary Hoy
- Department of Pediatrics, Division of Infectious Diseases, University of Rochester Medical Center, Rochester, New York, USA
| | - Terry W Wright
- Department of Pediatrics, Division of Infectious Diseases, University of Rochester Medical Center, Rochester, New York, USA
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, USA
| | - Michael Elliott
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, USA
| | - Jane Malone
- Department of Pediatrics, Division of Infectious Diseases, University of Rochester Medical Center, Rochester, New York, USA
| | - Samir Bhagwat
- Department of Pediatrics, Division of Infectious Diseases, University of Rochester Medical Center, Rochester, New York, USA
| | - Jing Wang
- Department of Pediatrics, Division of Infectious Diseases, University of Rochester Medical Center, Rochester, New York, USA
| | - Francis Gigliotti
- Department of Pediatrics, Division of Infectious Diseases, University of Rochester Medical Center, Rochester, New York, USA
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, USA
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2
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Fritzsch R, Donaldson PM, Greetham GM, Towrie M, Parker AW, Baker MJ, Hunt NT. Rapid Screening of DNA–Ligand Complexes via 2D-IR Spectroscopy and ANOVA–PCA. Anal Chem 2018; 90:2732-2740. [DOI: 10.1021/acs.analchem.7b04727] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Robby Fritzsch
- Department
of Physics, University of Strathclyde, SUPA, 107 Rottenrow East, Glasgow G4 0NG, U.K
| | - Paul M. Donaldson
- STFC
Central Laser Facility, Research Complex at Harwell, Rutherford Appleton
Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0QX, U.K
| | - Gregory M. Greetham
- STFC
Central Laser Facility, Research Complex at Harwell, Rutherford Appleton
Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0QX, U.K
| | - Michael Towrie
- STFC
Central Laser Facility, Research Complex at Harwell, Rutherford Appleton
Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0QX, U.K
| | - Anthony W. Parker
- STFC
Central Laser Facility, Research Complex at Harwell, Rutherford Appleton
Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0QX, U.K
| | - Matthew J. Baker
- WestCHEM,
Department of Pure and Applied Chemistry, Technology and Innovation
Centre, University of Strathclyde, 99 George Street, Glasgow G1 1RD, U.K
| | - Neil T. Hunt
- Department
of Physics, University of Strathclyde, SUPA, 107 Rottenrow East, Glasgow G4 0NG, U.K
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3
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Ranjan N, Kellish P, King A, Arya DP. Impact of Linker Length and Composition on Fragment Binding and Cell Permeation: Story of a Bisbenzimidazole Dye Fragment. Biochemistry 2017; 56:6434-6447. [PMID: 29131946 DOI: 10.1021/acs.biochem.7b00929] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Small molecules that modulate biological functions are targets of modern day drug discovery efforts. In a common platform fragment-based drug discovery, two fragments that bind to adjacent sites on a target are identified and are then linked together using different linkers to identify the linkage for optimum activity. What are not known from these studies are the effects these linkers, which typically contain C, H, and O atoms, have on the properties of the individual fragment. Herein, we investigate such effects in a bisbenzimidazole fragment whose derivatives have a wide range of therapeutic applications in nucleic acid recognition, sensing, and photodynamic therapy and as cellular probes. We report a dramatic effect of linker length and composition of alkynyl (clickable) Hoechst 33258 derivatives in target binding and cell uptake. We show that the binding of Hoechst 33258-modeled bisbenzimidazoles (1-9) that contain linkers of varying lengths (3-21 atoms) display length- and composition-dependent variation in B-DNA stabilization using a variety of spectroscopic methods. For a dodecamer DNA duplex, the thermal stabilization varied from 0.3 to 9.0 °C as the linker length increased from 3 to 21 atoms, respectively. Compounds with linker lengths of ≤11 atoms (such as compounds 1 and 5) are localized in the nucleus, while compounds with long linkers (such as compounds 8 and 9) are distributed in the extranuclear space, as well, with possible interactions with extranuclear targets. These findings provide insights into future drug design by revealing how linkers can influence the biophysical and cellular properties of individual drug fragments.
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Affiliation(s)
- Nihar Ranjan
- Laboratory of Medicinal Chemistry, Department of Chemistry, Clemson University , Clemson, South Carolina 29634, United States
| | - Patrick Kellish
- Laboratory of Medicinal Chemistry, Department of Chemistry, Clemson University , Clemson, South Carolina 29634, United States
| | - Ada King
- NUBAD LLC , 900 B West Faris Road, Greenville, South Carolina 29605, United States
| | - Dev P Arya
- Laboratory of Medicinal Chemistry, Department of Chemistry, Clemson University , Clemson, South Carolina 29634, United States.,NUBAD LLC , 900 B West Faris Road, Greenville, South Carolina 29605, United States
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4
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Ranjan N, Story S, Fulcrand G, Leng F, Ahmad M, King A, Sur S, Wang W, Tse-Dinh YC, Arya DP. Selective Inhibition of Escherichia coli RNA and DNA Topoisomerase I by Hoechst 33258 Derived Mono- and Bisbenzimidazoles. J Med Chem 2017; 60:4904-4922. [DOI: 10.1021/acs.jmedchem.7b00191] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Nihar Ranjan
- Laboratory
of Medicinal Chemistry, Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States
| | - Sandra Story
- NUBAD LLC, 900B West Faris
Road, Greenville, South Carolina 29605, United States
| | - Geraldine Fulcrand
- Department
of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States
- Biomolecular
Sciences Institute, Florida International University, Miami, Florida 33199, United States
| | - Fenfei Leng
- Department
of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States
- Biomolecular
Sciences Institute, Florida International University, Miami, Florida 33199, United States
| | - Muzammil Ahmad
- Genome
Instability and Chromatin Remodeling Section, Lab of Genetics, National
Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Baltimore, Maryland 21224, United States
| | - Ada King
- NUBAD LLC, 900B West Faris
Road, Greenville, South Carolina 29605, United States
| | - Souvik Sur
- Laboratory
of Medicinal Chemistry, Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States
| | - Weidong Wang
- Genome
Instability and Chromatin Remodeling Section, Lab of Genetics, National
Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Baltimore, Maryland 21224, United States
| | - Yuk-Ching Tse-Dinh
- Department
of Chemistry and Biochemistry, Florida International University, Miami, Florida 33199, United States
- Biomolecular
Sciences Institute, Florida International University, Miami, Florida 33199, United States
| | - Dev P. Arya
- Laboratory
of Medicinal Chemistry, Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States
- NUBAD LLC, 900B West Faris
Road, Greenville, South Carolina 29605, United States
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5
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Synthesis and investigation of novel benzimidazole derivatives as antifungal agents. Bioorg Med Chem 2016; 24:3680-6. [PMID: 27301676 DOI: 10.1016/j.bmc.2016.06.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 05/27/2016] [Accepted: 06/03/2016] [Indexed: 01/02/2023]
Abstract
The rise and emergence of resistance to antifungal drugs by diverse pathogenic fungal strains have resulted in an increase in demand for new antifungal agents. Various heterocyclic scaffolds with different mechanisms of action against fungi have been investigated in the past. Herein, we report the synthesis and antifungal activities of 18 alkylated mono-, bis-, and trisbenzimidazole derivatives, their toxicities against mammalian cells, as well as their ability to induce reactive oxygen species (ROS) in yeast cells. Many of our bisbenzimidazole compounds exhibited moderate to excellent antifungal activities against all tested fungal strains, with MIC values ranging from 15.6 to 0.975μg/mL. The fungal activity profiles of our bisbenzimidazoles were found to be dependent on alkyl chain length. Our most potent compounds were found to display equal or superior antifungal activity when compared to the currently used agents amphotericin B, fluconazole, itraconazole, posaconazole, and voriconazole against many of the strains tested.
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6
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Thymidine-Dependent Staphylococcus aureus Small-Colony Variants Are Induced by Trimethoprim-Sulfamethoxazole (SXT) and Have Increased Fitness during SXT Challenge. Antimicrob Agents Chemother 2015; 59:7265-72. [PMID: 26369968 DOI: 10.1128/aac.00742-15] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 09/04/2015] [Indexed: 11/20/2022] Open
Abstract
Trimethoprim-sulfamethoxazole (SXT) is a possible alternative for the treatment of community- and hospital-acquired methicillin-resistant Staphylococcus aureus (MRSA) due to the susceptibility of most MRSA strains to the drug. However, after long-term treatment with SXT, thymidine-dependent (TD) SXT-resistant small-colony variants (SCVs) emerge. In TD-SCVs, mutations of thymidylate synthase ([TS] thyA) occur. Until now, it has never been systematically investigated that SXT is triggering the induction and/or selection of TD-SCVs. In our study, we performed induction, reversion, and competition experiments in vitro and in vivo using a chronic mouse pneumonia model to determine the impact of SXT on the emergence of TD-SCVs. SCVs were characterized by light and transmission electron microscopy (TEM) and auxotrophism testing. Short-term exposure of S. aureus to SXT induced the TD-SCV phenotype in S. aureus SH1000, while selection of TD-SCVs with thyA mutations occurred after long-term exposure. In reversion experiments with clinical and laboratory TD-SCVs, all revertants carried compensating mutations at the initially identified mutation site. Competition experiments in vitro and in vivo revealed a survival and growth advantage of the ΔthyA mutant under low-thymidine availability and SXT exposure although this advantage was less profound in vivo. Our results show that SXT induces the TD-SCV phenotype after short-term exposure, while long-term exposure selects for thyA mutations, which provide an advantage for TD-SCVs under specified conditions. Thus, our results further an understanding of the dynamic processes occurring during SXT exposure with induction and selection of S. aureus TD-SCVs.
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7
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Barooah N, Mohanty J, Bhasikuttan AC. pH-Mediated Stoichiometric Switching of Cucurbit[8]uril–Hoechst-33258 Complexes. J Phys Chem B 2013; 117:13595-603. [DOI: 10.1021/jp405553g] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Nilotpal Barooah
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - Jyotirmayee Mohanty
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
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8
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Velagapudi SP, Seedhouse SJ, French J, Disney MD. Defining the RNA internal loops preferred by benzimidazole derivatives via 2D combinatorial screening and computational analysis. J Am Chem Soc 2011; 133:10111-8. [PMID: 21604752 DOI: 10.1021/ja200212b] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
RNA is an important therapeutic target; however, RNA targets are generally underexploited due to a lack of understanding of the small molecules that bind RNA and the RNA motifs that bind small molecules. Herein, we describe the identification of the RNA internal loops derived from a 4096 member 3 × 3 nucleotide loop library that are the most specific and highest affinity binders to a series of four designer, druglike benzimidazoles. These studies establish a potentially general protocol to define the highest affinity and most specific RNA motif targets for heterocyclic small molecules. Such information could be used to target functionally important RNAs in genomic sequence.
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Affiliation(s)
- Sai Pradeep Velagapudi
- Department of Chemistry, The University at Buffalo, The State University of New York, Buffalo, New York 14260, USA
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9
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Lomash S, Nagpal S, Salunke DM. An antibody as surrogate receptor reveals determinants of activity of an innate immune peptide antibiotic. J Biol Chem 2010; 285:35750-8. [PMID: 20837490 PMCID: PMC2975199 DOI: 10.1074/jbc.m110.150516] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 07/15/2010] [Indexed: 11/06/2022] Open
Abstract
Drug discovery initiatives often depend critically on knowledge of ligand-receptor interactions. However, the identity or structure of the target receptor may not be known in every instance. The concept of receptor surrogate, a molecular environment mimic of natural receptor, may prove beneficial under such circumstances. Here, we demonstrate the potential of monoclonal antibodies (mAbs) to act as surrogate receptors for a class of innate immune peptide antibiotics, a strategy that can help comprehend their action mechanism and identify chemical entities crucial for activity. A panel of antibody surrogates was raised against indolicidin, a tryptophan-rich cationic broad spectrum antimicrobial peptide of innate immune origin. Employing an elegant combination of thermodynamics, crystallography, and molecular modeling, interactions of the peptide with a high affinity anti-indolicidin monoclonal antibody were analyzed and were used to identify a motif that contained almost the entire antibiotic activity of native indolicidin. The analysis clarified the interaction of the peptide with previously proposed targets such as bacterial cell membrane and DNA and could further be correlated with antimicrobial compounds whose actions involve varied other mechanisms. These features suggest a multipronged assault pathway for indolicidin. Remarkably, the anti-indolicidin mAb surrogate was able to isolate additional independent bactericidal sequences from a random peptide library, providing compelling evidence as to the physiological relevance of surrogate receptor concept and suggesting applications in receptor-based pharmacophore research.
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MESH Headings
- Amino Acid Motifs
- Amino Acid Sequence
- Animals
- Anti-Infective Agents/immunology
- Anti-Infective Agents/metabolism
- Anti-Infective Agents/pharmacology
- Antibodies, Monoclonal/chemistry
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/metabolism
- Antimicrobial Cationic Peptides/immunology
- Antimicrobial Cationic Peptides/metabolism
- Antimicrobial Cationic Peptides/pharmacology
- Crystallography, X-Ray
- Epitope Mapping
- Epitopes/chemistry
- Epitopes/immunology
- Epitopes/metabolism
- Escherichia coli/drug effects
- Escherichia coli/growth & development
- Immunity, Innate/immunology
- Immunoglobulin Fragments/chemistry
- Immunoglobulin Fragments/immunology
- Immunoglobulin Fragments/metabolism
- Kinetics
- Mice
- Mice, Inbred BALB C
- Models, Molecular
- Peptide Library
- Protein Binding
- Protein Conformation
- Protein Structure, Tertiary
- Receptors, Immunologic/chemistry
- Receptors, Immunologic/immunology
- Receptors, Immunologic/metabolism
- Staphylococcus aureus/drug effects
- Staphylococcus aureus/growth & development
- Thermodynamics
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Affiliation(s)
- Suvendu Lomash
- From the Structural Biology Unit, National Institute of Immunology, Aruna Asaf Ali Road, New Delhi 110067 and
| | - Sushma Nagpal
- From the Structural Biology Unit, National Institute of Immunology, Aruna Asaf Ali Road, New Delhi 110067 and
| | - Dinakar M. Salunke
- From the Structural Biology Unit, National Institute of Immunology, Aruna Asaf Ali Road, New Delhi 110067 and
- the Regional Centre for Biotechnology, Gurgaon 122016, India
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10
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Bhagwat SP, Wright TW, Gigliotti F. Anti-CD3 antibody decreases inflammation and improves outcome in a murine model of Pneumocystis pneumonia. THE JOURNAL OF IMMUNOLOGY 2009; 184:497-502. [PMID: 19949093 DOI: 10.4049/jimmunol.0901864] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The T cell-mediated immune response elicited by Pneumocystis plays a key role in pulmonary damage and dysfunction during Pneumocystis carinii pneumonia (PcP). Mice depleted of CD4(+) and CD8(+) T cells prior to infection are markedly protected from PcP-related respiratory deficit and death, despite progressive lung infection. However, the therapeutic effectiveness of Ab-mediated disruption of T cell function in mice already displaying clinical symptoms of disease has not been determined. Therefore, a murine model of PcP-related immune reconstitution inflammatory syndrome was used to assess whether Ab to the pan-T cell molecule CD3 is effective for reducing the severity of PcP when administered after the onset of disease. Mice that received anti-CD3 Ab exhibited a rapid and dramatic halt in the PcP-associated pulmonary function decline within 1 week after treatment, and a striking enhancement of survival rate compared with mice receiving the control Ab. Physiologic improvement in anti-CD3 treated mice was associated with a significant reduction in the number of CD4(+) and CD8(+) T cells recovered in lung lavage fluid. This effectiveness of anti-CD3 was noted whether the mice also received antibiotic therapy with trimethoprim-sulfamethoxazole. These data suggest that monoclonal Ab-mediated disruption of T cell function may represent a specific and effective adjunctive therapy to rapidly reverse the ongoing pathologic immune response occurring during active PcP. Thus, the anti-human CD3 monoclonal Ab OKT3, which is already in clinical use, has the potential to be developed as an adjunctive therapy for PcP.
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Affiliation(s)
- Samir P Bhagwat
- Department of Pediatrics, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
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11
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Pushechnikov A, Lee MM, Childs-Disney JL, Sobczak K, French JM, Thornton CA, Disney MD. Rational design of ligands targeting triplet repeating transcripts that cause RNA dominant disease: application to myotonic muscular dystrophy type 1 and spinocerebellar ataxia type 3. J Am Chem Soc 2009; 131:9767-79. [PMID: 19552411 PMCID: PMC2731475 DOI: 10.1021/ja9020149] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Herein, we describe the design of high affinity ligands that bind expanded rCUG and rCAG repeat RNAs expressed in myotonic dystrophy type 1 (DM1) and spinocerebellar ataxia type 3. These ligands also inhibit, with nanomolar IC(50) values, the formation of RNA-protein complexes that are implicated in both disorders. The expanded rCUG and rCAG repeats form stable RNA hairpins with regularly repeating internal loops in the stem and have deleterious effects on cell function. The ligands that bind the repeats display a derivative of the bisbenzimidazole Hoechst 33258, which was identified by searching known RNA-ligand interactions for ligands that bind the internal loop displayed in these hairpins. A series of 13 modularly assembled ligands with defined valencies and distances between ligand modules was synthesized to target multiple motifs in these RNAs simultaneously. The most avid binder, a pentamer, binds the rCUG repeat hairpin with a K(d) of 13 nM. When compared to a series of related RNAs, the pentamer binds to rCUG repeats with 4.4- to >200-fold specificity. Furthermore, the affinity of binding to rCUG repeats shows incremental gains with increasing valency, while the background binding to genomic DNA is correspondingly reduced. Then, it was determined whether the modularly assembled ligands inhibit the recognition of RNA repeats by Muscleblind-like 1 (MBNL1) protein, the expanded-rCUG binding protein whose sequestration leads to splicing defects in DM1. Among several compounds with nanomolar IC(50) values, the most potent inhibitor is the pentamer, which also inhibits the formation of rCAG repeat-MBNL1 complexes. Comparison of the binding data for the designed synthetic ligands and MBNL1 to repeating RNAs shows that the synthetic ligand is 23-fold higher affinity and more specific to DM1 RNAs than MBNL1. Further studies show that the designed ligands are cell permeable to mouse myoblasts. Thus, cell permeable ligands that bind repetitive RNAs have been designed that exhibit higher affinity and specificity for binding RNA than natural proteins. These studies suggest a general approach to targeting RNA, including those that cause RNA dominant disease.
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Affiliation(s)
- Alexei Pushechnikov
- Department of Chemistry and The Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, The State University of New York, 657 Natural Sciences Complex, Buffalo, NY 14260
| | - Melissa M. Lee
- Department of Chemistry and The Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, The State University of New York, 657 Natural Sciences Complex, Buffalo, NY 14260
| | | | - Krzysztof Sobczak
- Department of Neurology, University of Rochester, Rochester, NY, 14620
| | - Jonathan M. French
- Department of Chemistry and The Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, The State University of New York, 657 Natural Sciences Complex, Buffalo, NY 14260
| | | | - Matthew D. Disney
- Department of Chemistry and The Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, The State University of New York, 657 Natural Sciences Complex, Buffalo, NY 14260
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12
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Grant L, Sun J, Xu H, Subramony S, Chaires JB, Hebert MD. Rational selection of small molecules that increase transcription through the GAA repeats found in Friedreich's ataxia. FEBS Lett 2006; 580:5399-405. [PMID: 16989817 PMCID: PMC1847611 DOI: 10.1016/j.febslet.2006.09.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Revised: 09/02/2006] [Accepted: 09/05/2006] [Indexed: 02/02/2023]
Abstract
Friedreich's ataxia (FRDA) is an autosomal recessive trinucleotide repeat disease with no effective therapy. Expanded GAA repeats in the first intron of the FRDA gene are thought to form unusual non-B DNA conformations that decrease transcription and subsequently reduce levels of the encoded protein, frataxin. Frataxin plays a crucial role in iron metabolism and detoxification. To discover small molecules that increase transcription through the GAA repeat region in FRDA, we have made stable cell lines containing a portion of expanded intron 1 fused to a GFP reporter. Small molecules identified using the competition dialysis method were found to increase FRDA-intron 1-reporter gene expression. One of these compounds, pentamidine, increases frataxin levels in patient cells. Thus our approach can be used to detect small molecules of potential therapeutic value in FRDA.
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Affiliation(s)
- LaKechia Grant
- Department of Biochemistry, 2500 North State Street, The University of Mississippi Medical Center, Jackson, MS 39216-4505, USAJames Graham Brown Cancer Center
| | - Jun Sun
- Department of Neurology, 2500 North State Street, The University of Mississippi Medical Center, Jackson, MS 39216-4505, USA
| | - Hongzhi Xu
- Department of Biochemistry, 2500 North State Street, The University of Mississippi Medical Center, Jackson, MS 39216-4505, USAJames Graham Brown Cancer Center
| | - S.H. Subramony
- Department of Neurology, 2500 North State Street, The University of Mississippi Medical Center, Jackson, MS 39216-4505, USA
| | - Jonathan B. Chaires
- James Graham Brown Cancer Center, Department of Medicine, Health Sciences Center, 529 South Jackson Street, University of Louisville, KY 40202, USA
| | - Michael D. Hebert
- Department of Biochemistry, 2500 North State Street, The University of Mississippi Medical Center, Jackson, MS 39216-4505, USAJames Graham Brown Cancer Center
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