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Wu P, Becker FB, Ogelman R, Camci ED, Linbo TH, Simon JA, Rubel EW, Raible DW. Multiple mechanisms of aminoglycoside ototoxicity are distinguished by subcellular localization of action. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.30.596537. [PMID: 39005374 PMCID: PMC11244871 DOI: 10.1101/2024.05.30.596537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Mechanosensory hair cells of the inner ears and lateral line of vertebrates display heightened vulnerability to environmental insult, with damage resulting in hearing and balance disorders. An important example is hair cell loss due to exposure to toxic agents including therapeutic drugs such as the aminoglycoside antibiotics such as neomycin and gentamicin and antineoplastic agents. We describe two distinct cellular pathways for aminoglycoside-induced hair cell death in zebrafish lateral line hair cells. Neomycin exposure results in death from acute exposure with most cells dying within 1 hour of exposure. By contrast, exposure to gentamicin results primarily in delayed hair cell death, taking up to 24 hours for maximal effect. Washout experiments demonstrate that delayed death does not require continuous exposure, demonstrating two mechanisms where downstream responses differ in their timing. Acute damage is associated with mitochondrial calcium fluxes and can be alleviated by the mitochondrially-targeted antioxidant mitoTEMPO, while delayed death is independent of these factors. Conversely delayed death is associated with lysosomal accumulation and is reduced by altering endolysosomal function, while acute death is not sensitive to lysosomal manipulations. These experiments reveal the complexity of responses of hair cells to closely related compounds, suggesting that intervention focusing on early events rather than specific death pathways may be a successful therapeutic strategy.
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Affiliation(s)
- Patricia Wu
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195, United States
- Department of Biological Structure, University of Washington, Seattle, WA 98195, United States
| | - Francisco Barros Becker
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195, United States
- Department of Otolaryngology-HNS, University of Washington, Seattle, WA 98195, United States
| | - Roberto Ogelman
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195, United States
- Department of Biological Structure, University of Washington, Seattle, WA 98195, United States
| | - Esra D. Camci
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195, United States
- Department of Otolaryngology-HNS, University of Washington, Seattle, WA 98195, United States
| | - Tor H. Linbo
- Department of Biological Structure, University of Washington, Seattle, WA 98195, United States
- Department of Otolaryngology-HNS, University of Washington, Seattle, WA 98195, United States
| | - Julian A. Simon
- Clinical Research, Human Biology, and Public Health Sciences Divisions, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, United States
| | - Edwin W Rubel
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195, United States
| | - David W. Raible
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195, United States
- Department of Biological Structure, University of Washington, Seattle, WA 98195, United States
- Department of Otolaryngology-HNS, University of Washington, Seattle, WA 98195, United States
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2
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Ward C, Beharry A, Tennakoon R, Rozik P, Wilhelm SDP, Heinemann IU, O’Donoghue P. Mechanisms and Delivery of tRNA Therapeutics. Chem Rev 2024; 124:7976-8008. [PMID: 38801719 PMCID: PMC11212642 DOI: 10.1021/acs.chemrev.4c00142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/11/2024] [Accepted: 04/26/2024] [Indexed: 05/29/2024]
Abstract
Transfer ribonucleic acid (tRNA) therapeutics will provide personalized and mutation specific medicines to treat human genetic diseases for which no cures currently exist. The tRNAs are a family of adaptor molecules that interpret the nucleic acid sequences in our genes into the amino acid sequences of proteins that dictate cell function. Humans encode more than 600 tRNA genes. Interestingly, even healthy individuals contain some mutant tRNAs that make mistakes. Missense suppressor tRNAs insert the wrong amino acid in proteins, and nonsense suppressor tRNAs read through premature stop signals to generate full length proteins. Mutations that underlie many human diseases, including neurodegenerative diseases, cancers, and diverse rare genetic disorders, result from missense or nonsense mutations. Thus, specific tRNA variants can be strategically deployed as therapeutic agents to correct genetic defects. We review the mechanisms of tRNA therapeutic activity, the nature of the therapeutic window for nonsense and missense suppression as well as wild-type tRNA supplementation. We discuss the challenges and promises of delivering tRNAs as synthetic RNAs or as gene therapies. Together, tRNA medicines will provide novel treatments for common and rare genetic diseases in humans.
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Affiliation(s)
- Cian Ward
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Aruun Beharry
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Rasangi Tennakoon
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Peter Rozik
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Sarah D. P. Wilhelm
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Ilka U. Heinemann
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
| | - Patrick O’Donoghue
- Department of Biochemistry, Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada
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3
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Vishy CE, Thomas C, Vincent T, Crawford DK, Goddeeris MM, Freedman BS. Genetics of cystogenesis in base-edited human organoids reveal therapeutic strategies for polycystic kidney disease. Cell Stem Cell 2024; 31:537-553.e5. [PMID: 38579684 PMCID: PMC11325856 DOI: 10.1016/j.stem.2024.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 12/19/2023] [Accepted: 03/08/2024] [Indexed: 04/07/2024]
Abstract
In polycystic kidney disease (PKD), microscopic tubules expand into macroscopic cysts. Among the world's most common genetic disorders, PKD is inherited via heterozygous loss-of-function mutations but is theorized to require additional loss of function. To test this, we establish human pluripotent stem cells in allelic series representing four common nonsense mutations, using CRISPR base editing. When differentiated into kidney organoids, homozygous mutants spontaneously form cysts, whereas heterozygous mutants (original or base corrected) express no phenotype. Using these, we identify eukaryotic ribosomal selective glycosides (ERSGs) as PKD therapeutics enabling ribosomal readthrough of these same nonsense mutations. Two different ERSGs not only prevent cyst initiation but also limit growth of pre-formed cysts by partially restoring polycystin expression. Furthermore, glycosides accumulate in cyst epithelia in organoids and mice. Our findings define the human polycystin threshold as a surmountable drug target for pharmacological or gene therapy interventions, with relevance for understanding disease mechanisms and future clinical trials.
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Affiliation(s)
- Courtney E Vishy
- Division of Nephrology, Department of Medicine, Institute for Stem Cell and Regenerative Medicine, and Kidney Research Institute, University of Washington, Seattle, WA 98109, USA
| | - Chardai Thomas
- Division of Nephrology, Department of Medicine, Institute for Stem Cell and Regenerative Medicine, and Kidney Research Institute, University of Washington, Seattle, WA 98109, USA
| | - Thomas Vincent
- Division of Nephrology, Department of Medicine, Institute for Stem Cell and Regenerative Medicine, and Kidney Research Institute, University of Washington, Seattle, WA 98109, USA
| | - Daniel K Crawford
- Eloxx Pharmaceuticals, Inc., 950 Winter Street, Waltham, MA 02451, USA
| | | | - Benjamin S Freedman
- Division of Nephrology, Department of Medicine, Institute for Stem Cell and Regenerative Medicine, and Kidney Research Institute, University of Washington, Seattle, WA 98109, USA; Plurexa, 1209 6th Ave. N., Seattle, WA 98109, USA.
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4
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Wittenstein A, Caspi M, Rippin I, Elroy-Stein O, Eldar-Finkelman H, Thoms S, Rosin-Arbesfeld R. Nonsense mutation suppression is enhanced by targeting different stages of the protein synthesis process. PLoS Biol 2023; 21:e3002355. [PMID: 37943958 PMCID: PMC10684085 DOI: 10.1371/journal.pbio.3002355] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 11/28/2023] [Accepted: 09/29/2023] [Indexed: 11/12/2023] Open
Abstract
The introduction of premature termination codons (PTCs), as a result of splicing defects, insertions, deletions, or point mutations (also termed nonsense mutations), lead to numerous genetic diseases, ranging from rare neuro-metabolic disorders to relatively common inheritable cancer syndromes and muscular dystrophies. Over the years, a large number of studies have demonstrated that certain antibiotics and other synthetic molecules can act as PTC suppressors by inducing readthrough of nonsense mutations, thereby restoring the expression of full-length proteins. Unfortunately, most PTC readthrough-inducing agents are toxic, have limited effects, and cannot be used for therapeutic purposes. Thus, further efforts are required to improve the clinical outcome of nonsense mutation suppressors. Here, by focusing on enhancing readthrough of pathogenic nonsense mutations in the adenomatous polyposis coli (APC) tumor suppressor gene, we show that disturbing the protein translation initiation complex, as well as targeting other stages of the protein translation machinery, enhances both antibiotic and non-antibiotic-mediated readthrough of nonsense mutations. These findings strongly increase our understanding of the mechanisms involved in nonsense mutation readthrough and facilitate the development of novel therapeutic targets for nonsense suppression to restore protein expression from a large variety of disease-causing mutated transcripts.
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Affiliation(s)
- Amnon Wittenstein
- Department of Clinical Microbiology and Immunology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Michal Caspi
- Department of Clinical Microbiology and Immunology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ido Rippin
- The Department of Human Molecular Genetics & Biochemistry School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Orna Elroy-Stein
- Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Hagit Eldar-Finkelman
- The Department of Human Molecular Genetics & Biochemistry School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Sven Thoms
- Biochemistry and Molecular Medicine, Medical School EWL, Bielefeld University, Bielefeld, Germany
| | - Rina Rosin-Arbesfeld
- Department of Clinical Microbiology and Immunology, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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5
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Li S, Li J, Shi W, Nie Z, Zhang S, Ma F, Hu J, Chen J, Li P, Xie X. Pharmaceuticals Promoting Premature Termination Codon Readthrough: Progress in Development. Biomolecules 2023; 13:988. [PMID: 37371567 DOI: 10.3390/biom13060988] [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: 04/25/2023] [Revised: 05/27/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
Around 11% of all known gene lesions causing human genetic diseases are nonsense mutations that introduce a premature stop codon (PTC) into the protein-coding gene sequence. Drug-induced PTC readthrough is a promising therapeutic strategy for treating hereditary diseases caused by nonsense mutations. To date, it has been found that more than 50 small-molecular compounds can promote PTC readthrough, known as translational readthrough-inducing drugs (TRIDs), and can be divided into two major categories: aminoglycosides and non-aminoglycosides. This review summarizes the pharmacodynamics and clinical application potential of the main TRIDs discovered so far, especially some newly discovered TRIDs in the past decade. The discovery of these TRIDs brings hope for treating nonsense mutations in various genetic diseases. Further research is still needed to deeply understand the mechanism of eukaryotic cell termination and drug-induced PTC readthrough so that patients can achieve the greatest benefit from the various TRID treatments.
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Affiliation(s)
- Shan Li
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Juan Li
- Central Laboratory, The First Hospital of Lanzhou University, Lanzhou 730000, China
- Gansu Key Laboratory of Genetic Study of Hematopathy, The First Hospital of Lanzhou University, Lanzhou 730000, China
| | - Wenjing Shi
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Ziyan Nie
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Shasha Zhang
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Fengdie Ma
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jun Hu
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jianjun Chen
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China
| | - Peiqiang Li
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Xiaodong Xie
- School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
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6
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Guchhait S, Khononov A, Pieńko T, Belakhov V, Baasov T. Balancing Nonsense Mutation Readthrough and Toxicity of Designer Aminoglycosides for Treatment of Genetic Diseases. ACS Med Chem Lett 2023; 14:794-801. [PMID: 37312846 PMCID: PMC10258827 DOI: 10.1021/acsmedchemlett.3c00089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 04/17/2023] [Indexed: 06/15/2023] Open
Abstract
New derivatives of aminoglycosides with a side chain 1,2-aminoalcohol at the 5" position of ring III were designed, synthesized, and biologically evaluated. The novel lead structure (compound 6), exhibiting substantially enhanced selectivity toward eukaryotic versus prokaryotic ribosome, high readthrough activity, and considerably lower toxicity than the previous lead compounds, was discovered. Balanced readthrough activity and toxicity of 6 were demonstrated in three different nonsense DNA-constructs underlying the genetic diseases, cystic fibrosis and Usher syndrome, and in two different cell lines, baby hamster kidney and human embryonic kidney cells. Molecular dynamics simulations within the A site of the 80S yeast ribosome demonstrated a remarkable kinetic stability of 6, which potentially determines its high readthrough activity.
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7
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Chen J, Thrasher K, Fu L, Wang W, Aghamohammadzadeh S, Wen H, Tang L, Keeling KM, Falk Libby E, Bedwell DM, Rowe SM. The synthetic aminoglycoside ELX-02 induces readthrough of G550X-CFTR producing superfunctional protein that can be further enhanced by CFTR modulators. Am J Physiol Lung Cell Mol Physiol 2023; 324:L756-L770. [PMID: 37014818 PMCID: PMC10202470 DOI: 10.1152/ajplung.00038.2023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/29/2023] [Accepted: 04/02/2023] [Indexed: 04/05/2023] Open
Abstract
Ten percent of cystic fibrosis (CF) patients carry a premature termination codon (PTC); no mutation-specific therapies exist for these individuals. ELX-02, a synthetic aminoglycoside, suppresses translation termination at PTCs (i.e., readthrough) by promoting the insertion of an amino acid at the PTC and restoring expression of full-length CFTR protein. The identity of amino acids inserted at PTCs affects the processing and function of the resulting full-length CFTR protein. We examined readthrough of the rare G550X-CFTR nonsense mutation due to its unique properties. We found that forskolin-induced swelling in G550X patient-derived intestinal organoids (PDOs) was significantly higher than in G542X PDOs (both UGA PTCs) with ELX-02 treatment, indicating greater CFTR function from the G550X allele. Using mass spectrometry, we identified tryptophan as the sole amino acid inserted in the G550X position during ELX-02- or G418-mediated readthrough, which differs from the three amino acids (cysteine, arginine, and tryptophan) inserted in the G542X position after treatment with G418. Compared with wild-type CFTR, Fischer rat thyroid (FRT) cells expressing the G550W-CFTR variant protein exhibited significantly increased forskolin-activated Cl- conductance, and G550W-CFTR channels showed increased PKA sensitivity and open probability. After treatment with ELX-02 and CFTR correctors, CFTR function rescued from the G550X allele in FRTs reached 20-40% of the wild-type level. These results suggest that readthrough of G550X produces greater CFTR function because of gain-of-function properties of the CFTR readthrough product that stem from its location in the signature LSGGQ motif found in ATP-binding cassette (ABC) transporters. G550X may be a particularly sensitive target for translational readthrough therapy.NEW & NOTEWORTHY We found that forskolin-induced swelling in G550X-CFTR patient-derived intestinal organoids (PDOs) was significantly higher than in G542X-CFTR PDOs after treatment with ELX-02. Tryptophan (W) was the sole amino acid inserted in the G550X position after readthrough. Resulting G550W-CFTR protein exhibited supernormal CFTR activity, PKA sensitivity, and open probability. These results show that aminoglycoside-induced readthrough of G550X produces greater CFTR function because of the gain-of-function properties of the CFTR readthrough product.
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Affiliation(s)
- Jianguo Chen
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Kari Thrasher
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Lianwu Fu
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Wei Wang
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | | | - Hui Wen
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Liping Tang
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Kim M Keeling
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Emily Falk Libby
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - David M Bedwell
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Steven M Rowe
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States
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8
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Siddiqui A, Dundar H, Sharma J, Kaczmarczyk A, Echols J, Dai Y, Sun CR, Du M, Liu Z, Zhao R, Wood T, Sanders S, Rasmussen L, Bostwick JR, Augelli-Szafran C, Suto M, Rowe SM, Bedwell DM, Keeling KM. Triamterene Functions as an Effective Nonsense Suppression Agent for MPS I-H (Hurler Syndrome). Int J Mol Sci 2023; 24:4521. [PMID: 36901952 PMCID: PMC10003437 DOI: 10.3390/ijms24054521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 02/20/2023] [Accepted: 02/22/2023] [Indexed: 03/03/2023] Open
Abstract
Mucopolysaccharidosis I-Hurler (MPS I-H) is caused by the loss of α-L-iduronidase, a lysosomal enzyme that degrades glycosaminoglycans. Current therapies cannot treat many MPS I-H manifestations. In this study, triamterene, an FDA-approved, antihypertensive diuretic, was found to suppress translation termination at a nonsense mutation associated with MPS I-H. Triamterene rescued enough α-L-iduronidase function to normalize glycosaminoglycan storage in cell and animal models. This new function of triamterene operates through premature termination codon (PTC) dependent mechanisms that are unaffected by epithelial sodium channel activity, the target of triamterene's diuretic function. Triamterene represents a potential non-invasive treatment for MPS I-H patients carrying a PTC.
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Affiliation(s)
- Amna Siddiqui
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Halil Dundar
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Next Generation Sequencing Transplant Diagnostics, Thermo-Fisher Scientific, West Hills, CA 91304, USA
| | - Jyoti Sharma
- Cystic Fibrosis Research Center, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Division of Infectious Diseases, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Aneta Kaczmarczyk
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- ARUP Laboratories, Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Josh Echols
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yanying Dai
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Chuanxi Richard Sun
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Ming Du
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Cystic Fibrosis Research Center, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Zhong Liu
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Rui Zhao
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Tim Wood
- Greenwood Genetic Center, Greenwood, SC 29646, USA
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | | | | | | | | | - Mark Suto
- Southern Research, Birmingham, AL 35205, USA
| | - Steven M. Rowe
- Cystic Fibrosis Research Center, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - David M. Bedwell
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Cystic Fibrosis Research Center, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Kim M. Keeling
- Department of Biochemistry & Molecular Genetics, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Cystic Fibrosis Research Center, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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9
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Recoding of Nonsense Mutation as a Pharmacological Strategy. Biomedicines 2023; 11:biomedicines11030659. [PMID: 36979640 PMCID: PMC10044939 DOI: 10.3390/biomedicines11030659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/18/2023] [Accepted: 02/20/2023] [Indexed: 02/24/2023] Open
Abstract
Approximately 11% of genetic human diseases are caused by nonsense mutations that introduce a premature termination codon (PTC) into the coding sequence. The PTC results in the production of a potentially harmful shortened polypeptide and activation of a nonsense-mediated decay (NMD) pathway. The NMD pathway reduces the burden of unproductive protein synthesis by lowering the level of PTC mRNA. There is an endogenous rescue mechanism that produces a full-length protein from a PTC mRNA. Nonsense suppression therapies aim to increase readthrough, suppress NMD, or are a combination of both strategies. Therefore, treatment with translational readthrough-inducing drugs (TRIDs) and NMD inhibitors may increase the effectiveness of PTC suppression. Here we discuss the mechanism of PTC readthrough and the development of novel approaches to PTC suppression. We also discuss the toxicity and bioavailability of therapeutics used to stimulate PTC readthrough.
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10
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Pranke IM, Varilh J, Hatton A, Faucon C, Girodon E, Dreano E, Chevalier B, Karri S, Reix P, Durieu I, Bidou L, Namy O, Taulan M, Hinzpeter A, Sermet-Gaudelus I. The U UGA C sequence provides a favorable context to ELX-02 induced CFTR readthrough. J Cyst Fibros 2022:S1569-1993(22)01392-3. [DOI: 10.1016/j.jcf.2022.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 09/22/2022] [Accepted: 10/24/2022] [Indexed: 11/18/2022]
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11
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Liu C, Wang L, Sun Y, Zhao X, Chen T, Su X, Guo H, Wang Q, Xi X, Ding Y, Chen Y. Probe Synthesis Reveals Eukaryotic Translation Elongation Factor 1 Alpha 1 as the Anti‐Pancreatic Cancer Target of BE‐43547A
2. Angew Chem Int Ed Engl 2022; 61:e202206953. [DOI: 10.1002/anie.202206953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Indexed: 12/17/2022]
Affiliation(s)
- Can Liu
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
| | - Liang Wang
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
- College of Chemistry Nankai University 94 Weijin Road Tianjin 300071 P. R. China
| | - Yuanjun Sun
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
| | - Xiuhe Zhao
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
| | - Tianyang Chen
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
| | - Xiuwen Su
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
| | - Hui Guo
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
| | - Qin Wang
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
| | - Xiaonan Xi
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
| | - Yahui Ding
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
- College of Chemistry Nankai University 94 Weijin Road Tianjin 300071 P. R. China
| | - Yue Chen
- State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University 38 Tongyan Road Tianjin 300353 P. R. China
- College of Chemistry Nankai University 94 Weijin Road Tianjin 300071 P. R. China
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12
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Ataluren suppresses a premature termination codon in an MPS I-H mouse. J Mol Med (Berl) 2022; 100:1223-1235. [PMID: 35857082 PMCID: PMC9329424 DOI: 10.1007/s00109-022-02232-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/26/2022] [Accepted: 06/28/2022] [Indexed: 11/26/2022]
Abstract
Abstarct Suppressing translation termination at premature termination codons (PTCs), termed readthrough, is a potential therapy for genetic diseases caused by nonsense mutations. Ataluren is a compound that has shown promise for clinical use as a readthrough agent. However, some reports suggest that ataluren is ineffective at suppressing PTCs. To further evaluate the effectiveness of ataluren as a readthrough agent, we examined its ability to suppress PTCs in a variety of previously untested models. Using NanoLuc readthrough reporters expressed in two different cell types, we found that ataluren stimulated a significant level of readthrough. We also explored the ability of ataluren to suppress a nonsense mutation associated with Mucopolysaccharidosis I-Hurler (MPS I-H), a genetic disease that is caused by a deficiency of α-L-iduronidase that leads to lysosomal accumulation of glycosaminoglycans (GAGs). Using mouse embryonic fibroblasts (MEFs) derived from Idua-W402X mice, we found that ataluren partially rescued α-L-iduronidase function and significantly reduced GAG accumulation relative to controls. Two-week oral administration of ataluren to Idua-W402X mice led to significant GAG reductions in most tissues compared to controls. Together, these data reveal important details concerning the efficiency of ataluren as a readthrough agent and the mechanisms that govern its ability to suppress PTCs. Key messages Ataluren promotes readthrough of PTCs in a wide variety of contexts. Ataluren reduces glycosaminoglyan storage in MPS I-H cell and mouse models. Ataluren has a bell-shaped dose–response curve and a narrow effective range.
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13
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Liu C, Wang L, Sun Y, Zhao X, Chen T, Su X, Guo H, Wang Q, Xi X, Ding Y, Chen Y. Probe Synthesis Reveals Eukaryotic Translation Elongation Factor 1 Alpha 1 as the Anti‐Pancreatic Cancer Target of BE‐43547A2. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Can Liu
- Nankai University College of Pharmacy CHINA
| | - Liang Wang
- Nankai University College of Chemistry CHINA
| | | | - Xiuhe Zhao
- Nankai University College of Pharmacy CHINA
| | | | - Xiuwen Su
- Nankai University College of Pharmacy CHINA
| | - Hui Guo
- Nankai University College of Pharmacy CHINA
| | - Qin Wang
- Nankai University College of Pharmacy CHINA
| | - Xiaonan Xi
- Nankai University College of Pharmacy CHINA
| | - Yahui Ding
- Nankai University College of Chemistry CHINA
| | - Yue Chen
- Nankai University College of Pharmacy Weijin RoadNankai district 300071 Tianjin CHINA
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14
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Kim J, Hemachandran S, Cheng AG, Ricci AJ. Identifying targets to prevent aminoglycoside ototoxicity. Mol Cell Neurosci 2022; 120:103722. [PMID: 35341941 PMCID: PMC9177639 DOI: 10.1016/j.mcn.2022.103722] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 03/14/2022] [Accepted: 03/19/2022] [Indexed: 12/21/2022] Open
Abstract
Aminoglycosides are potent antibiotics that are commonly prescribed worldwide. Their use carries significant risks of ototoxicity by directly causing inner ear hair cell degeneration. Despite their ototoxic side effects, there are currently no approved antidotes. Here we review recent advances in our understanding of aminoglycoside ototoxicity, mechanisms of drug transport, and promising sites for intervention to prevent ototoxicity.
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Affiliation(s)
- Jinkyung Kim
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Sriram Hemachandran
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Alan G Cheng
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Anthony J Ricci
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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15
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Zhang Q, Wu Y, Yu Y, Niu Y, Fang Q, Chen X, Qi J, Zhang C, Wu G, Su K, Chai R. Tetrandrine Prevents Neomycin-Induced Ototoxicity by Promoting Steroid Biosynthesis. Front Bioeng Biotechnol 2022; 10:876237. [PMID: 35519614 PMCID: PMC9065337 DOI: 10.3389/fbioe.2022.876237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 03/18/2022] [Indexed: 11/23/2022] Open
Abstract
Aminoglycoside antibiotics are widely used for the treatment of serious acute infections, life-threatening sepsis, and tuberculosis, but all aminoglycosides cause side effects, especially irreversible ototoxicity. The mechanisms underlying the ototoxicity of aminoglycosides need further investigation, and there are no effective drugs in the clinic. Here we showed that tetrandrine (TET), a bioactive bisbenzylisoquinoline alkaloid derived from Stephania tetrandra, ameliorated neomycin-induced cochlear hair cell injury. In both in vitro and in vivo experiments we found that TET administration significantly improved auditory function and reduced hair cell damage after neomycin exposure. In addition, we observed that TET could significantly decrease oxidative stress and apoptosis in hair cells after neomycin exposure. Finally, RNA-seq analysis suggested that TET protected against neomycin-induced ototoxicity mainly by promoting steroid biosynthesis. Collectively, our results provide pharmacological evidence showing that TET may be a promising agent in preventing aminoglycosides-induced ototoxicity.
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Affiliation(s)
- Qilei Zhang
- The Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang, China
| | - Yunhao Wu
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
- *Correspondence: Yunhao Wu, ; Geping Wu, ; Kaiming Su, ; Renjie Chai,
| | - Yan Yu
- The Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang, China
| | - Yuguang Niu
- Department of Ambulatory Medicine, the First Medical Center of PLA General Hospital, Beijing, China
| | - Qiaojun Fang
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Xin Chen
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Jieyu Qi
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
| | - Chen Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Key Laboratory of Neural Regeneration and Repair, Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Geping Wu
- The Affiliated Zhangjiagang Hospital of Soochow University, Zhangjiagang, China
- *Correspondence: Yunhao Wu, ; Geping Wu, ; Kaiming Su, ; Renjie Chai,
| | - Kaiming Su
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- *Correspondence: Yunhao Wu, ; Geping Wu, ; Kaiming Su, ; Renjie Chai,
| | - Renjie Chai
- State Key Laboratory of Bioelectronics, Department of Otolaryngology Head and Neck Surgery, Zhongda Hospital, School of Life Sciences and Technology, Advanced Institute for Life and Health, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China
- Department of Otolaryngology Head and Neck Surgery, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Science, Beijing, China
- Beijing Key Laboratory of Neural Regeneration and Repair, Capital Medical University, Beijing, China
- *Correspondence: Yunhao Wu, ; Geping Wu, ; Kaiming Su, ; Renjie Chai,
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16
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Scalcon V, Folda A, Lupo MG, Tonolo F, Pei N, Battisti I, Ferri N, Arrigoni G, Bindoli A, Holmgren A, Coppo L, Rigobello MP. Mitochondrial depletion of glutaredoxin 2 induces metabolic dysfunction-associated fatty liver disease in mice. Redox Biol 2022; 51:102277. [PMID: 35290904 PMCID: PMC8921303 DOI: 10.1016/j.redox.2022.102277] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/18/2022] [Accepted: 02/26/2022] [Indexed: 12/13/2022] Open
Abstract
Glutaredoxin 2 (Grx2) is a glutathione-dependent oxidoreductase that facilitates glutathionylation/de-glutathionylation of target proteins. The main variants of Grx2 are the mitochondrial Grx2a and the cytosolic Grx2c. The aim of this study was to investigate the specific role of mitochondrial Grx2 in vivo using a mitochondrial Grx2 depleted (mGD) mouse model. mGD mice displayed an altered mitochondrial morphology and functioning. Furthermore, the lack of Grx2 in the mitochondrial compartment is responsible for increased blood lipid levels under a normal diet, a metabolic dysfunction-associated fatty liver disease (MAFLD) phenotype and a decreased glycogen storage capacity. In addition, depleting Grx2a leads to an alteration in abundance and in glutathionylation pattern of different mitochondrial enzymes, highlighting the selective role of Grx2 in the regulation of metabolic pathways. Overall, our findings identify the involvement of mitochondrial Grx2a in the regulation of cell metabolism and highlight a previously unknown association between Grx2 and MAFLD. Mitochondrial Grx2 depleted (mGD) mice display mitochondrial impairment. mGD mice show alterations in lipid metabolism and glycogen storage in the liver. Upon Grx2 deficiency the glutathionylation pattern of metabolic enzymes changes Mitochondrial Grx2 depletion is associated with MAFLD development
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Affiliation(s)
- Valeria Scalcon
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy
| | - Alessandra Folda
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy
| | | | - Federica Tonolo
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy
| | - Naixuan Pei
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17165, Stockholm, Sweden
| | - Ilaria Battisti
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy; Proteomics Center, University of Padova and Azienda Ospedaliera di Padova, 35129, Padova, Italy
| | - Nicola Ferri
- Department of Medicine, University of Padova, 35121, Padova, Italy
| | - Giorgio Arrigoni
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy; Proteomics Center, University of Padova and Azienda Ospedaliera di Padova, 35129, Padova, Italy
| | - Alberto Bindoli
- Institute of Neuroscience, CNR c/o Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy
| | - Arne Holmgren
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17165, Stockholm, Sweden
| | - Lucia Coppo
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17165, Stockholm, Sweden.
| | - Maria Pia Rigobello
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy.
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17
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Omachi K, Kai H, Roberge M, Miner JH. Full-length and split-NanoLuc reporters identify pathogenic COL4A5 nonsense mutations susceptible to premature termination codon readthrough. iScience 2022; 25:103891. [PMID: 35243249 PMCID: PMC8866893 DOI: 10.1016/j.isci.2022.103891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 12/22/2021] [Accepted: 02/04/2022] [Indexed: 11/02/2022] Open
Abstract
Alport syndrome, a disease of kidney, ear, and eye, is caused by pathogenic variants in the COL4A3, COL4A4, or COL4A5 genes encoding collagen α3α4α5(IV) of basement membranes. Collagen IV chains that are truncated due to nonsense variants/premature termination codons (PTCs) cannot assemble into heterotrimers or incorporate into basement membranes. To investigate the feasibility of PTC readthrough therapy for Alport syndrome, we utilized two NanoLuc reporters in transfected cells: full-length for monitoring translation, and a split version for assessing readthrough product function. Full-length assays of 49 COL4A5 nonsense variants identified eleven as susceptible to PTC readthrough using various readthrough drugs. In split-NanoLuc assays, the predicted missense α5(IV) readthrough products of five nonsense mutations could heterotrimerize with α3(IV) and α4(IV). Readthrough was also observed in kidney cells from an engineered Col4a5 PTC mouse model. These results suggest that readthrough therapy is a feasible approach for a fraction of patients with Alport syndrome. NanoLuc fusion constructs identified COL4A5 mutants susceptible to PTC readthrough Readthrough enhancer and “designer” compounds promoted PTC readthrough Split-NanoLuc fusion constructs identified functional missense readthrough products Cultured Col4a5 nonsense mutant mouse kidney cells were susceptible to readthrough
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18
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Diepstraten FA, Hoetink AE, van Grotel M, Huitema ADR, Stokroos RJ, van den Heuvel-Eibrink MM, Meijer AJM. Aminoglycoside- and glycopeptide-induced ototoxicity in children: a systematic review. JAC Antimicrob Resist 2021; 3:dlab184. [PMID: 34917943 PMCID: PMC8669239 DOI: 10.1093/jacamr/dlab184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 11/16/2021] [Indexed: 11/25/2022] Open
Abstract
Background Ototoxicity has been reported after administration of aminoglycosides and glycopeptides. Objectives To identify available evidence for the occurrence and determinants of aminoglycoside- and glycopeptide-related ototoxicity in children. Materials and methods Systematic electronic literature searches that combined ototoxicity (hearing loss, tinnitus and/or vertigo) with intravenous aminoglycoside and/or glycopeptide administration in children were performed in PubMed, EMBASE and Cochrane Library databases. Studies with sample sizes of ≥50 children were included. The QUIPS tool and Cochrane criteria were used to assess the quality and risk of bias of included studies. Results Twenty-nine aminoglycoside-ototoxicity studies met the selection criteria (including 7 randomized controlled trials). Overall study quality was medium/low. The frequency of hearing loss within these studies ranged from 0%–57%, whereas the frequency of tinnitus and vertigo ranged between 0%–53% and 0%–79%, respectively. Two studies met the criteria on glycopeptide-induced ototoxicity and reported hearing loss frequencies of 54% and 55%. Hearing loss frequencies were higher in gentamicin-treated children compared to those treated with other aminoglycosides. In available studies aminoglycosides had most often been administered concomitantly with platinum agents, diuretics and other co-medication. Conclusions In children the reported occurrence of aminoglycoside/glycopeptide ototoxicity highly varies and seems to depend on the diagnosis, aminoglycoside subtype and use of co-administered medication. More research is needed to investigate the prevalence and determinants of aminoglycoside/glycopeptide ototoxicity. Our results indicate that age-dependent audiological examination may be considered for children frequently treated with aminoglycosides/glycopeptides especially if combined with other ototoxic medication.
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Affiliation(s)
- F A Diepstraten
- Princess Máxima Center for pediatric oncology, Utrecht, The Netherlands
| | - A E Hoetink
- Department of Otorhinolaryngology-Head and Neck Surgery, University Medical Centre Utrecht, UMC Brain Centre, Utrecht, The Netherlands
| | - M van Grotel
- Princess Máxima Center for pediatric oncology, Utrecht, The Netherlands
| | - A D R Huitema
- Princess Máxima Center for pediatric oncology, Utrecht, The Netherlands.,Department of Pharmacy and Pharmacology, Netherlands Cancer Institute, Amsterdam, The Netherlands.,Department of Clinical Pharmacy, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - R J Stokroos
- Department of Otorhinolaryngology-Head and Neck Surgery, University Medical Centre Utrecht, UMC Brain Centre, Utrecht, The Netherlands
| | - M M van den Heuvel-Eibrink
- Princess Máxima Center for pediatric oncology, Utrecht, The Netherlands.,Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - A J M Meijer
- Princess Máxima Center for pediatric oncology, Utrecht, The Netherlands
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19
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Jia G, Mao H, Zhang Y, Ni Y, Chen Y. Apigenin alleviates neomycin-induced oxidative damage via the Nrf2 signaling pathway in cochlear hair cells. Front Med 2021; 16:637-650. [PMID: 34921675 DOI: 10.1007/s11684-021-0864-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 04/25/2021] [Indexed: 10/19/2022]
Abstract
Oxidative stress plays an important role in the pathogenesis of aminoglycoside-induced hearing loss and represents a promising target for treatment. We tested the potential effect of apigenin, a natural flavonoid with anticancer, anti-inflammatory, and antioxidant activities, on neomycin-induced ototoxicity in cochlear hair cells in vitro. Results showed that apigenin significantly ameliorated the loss of hair cells and the accumulation of reactive oxygen species upon neomycin injury. Further evidence suggested that the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway was activated by apigenin treatment. Disruption of the Nrf2 axis abolished the effects of apigenin on the alleviation of oxidative stress and subsequent apoptosis of hair cells. This study provided evidence of the protective effect of apigenin on cochlear hair cells and its underlying mechanism.
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Affiliation(s)
- Gaogan Jia
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, 200031, China.,NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Huanyu Mao
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, 200031, China.,NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Yanping Zhang
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, 200031, China.,NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Yusu Ni
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, 200031, China. .,NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China.
| | - Yan Chen
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, 200031, China. .,NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China.
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20
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Yusupova G, Yusupov M. A Path to the Atomic-Resolution Structures of Prokaryotic and Eukaryotic Ribosomes. BIOCHEMISTRY (MOSCOW) 2021; 86:926-941. [PMID: 34488570 DOI: 10.1134/s0006297921080046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Resolving first crystal structures of prokaryotic and eukaryotic ribosomes by our group has been based on the knowledge accumulated over the decades of studies, starting with the first electron microscopy images of the ribosome obtained by J. Pallade in 1955. In 1983, A. Spirin, then a Director of the Protein Research Institute of the USSR Academy of Sciences, initiated the first study aimed at solving the structure of ribosomes using X-ray structural analysis. In 1999, our group in collaboration with H. Noller published the first crystal structure of entire bacterial ribosome in a complex with its major functional ligands, such as messenger RNA and three transport RNAs at the A, P, and E sites. In 2011, our laboratory published the first atomic-resolution structure of eukaryotic ribosome solved by the X-ray diffraction analysis that confirmed the conserved nature of the main ribosomal functional components, such as the decoding and peptidyl transferase centers, was confirmed, and eukaryote-specific elements of the ribosome were described. Using X-ray structural analysis, we investigated general principles of protein biosynthesis inhibition in eukaryotic ribosomes, along with the mechanisms of antibiotic resistance. Structural differences between bacterial and eukaryotic ribosomes that determine the differences in their inhibition were established. These and subsequent atomic-resolution structures of the functional ribosome demonstrated for the first time the details of binding of messenger and transport RNAs, which was the first step towards understanding how the ribosome structure ultimately determines its functions.
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Affiliation(s)
- Gulnara Yusupova
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR7104, Université de Strasbourg, Illkirch, 67404, France
| | - Marat Yusupov
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR7104, Université de Strasbourg, Illkirch, 67404, France. .,Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, 420008, Russia
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21
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Brönstrup M, Sasse F. Natural products targeting the elongation phase of eukaryotic protein biosynthesis. Nat Prod Rep 2021; 37:752-762. [PMID: 32428051 DOI: 10.1039/d0np00011f] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Covering: 2000 to 2020 The translation of mRNA into proteins is a precisely regulated, complex process that can be divided into three main stages, i.e. initiation, elongation, termination, and recycling. This contribution is intended to highlight how natural products interfere with the elongation phase of eukaryotic protein biosynthesis. Cycloheximide, isolated from Streptomyces griseus, has long been the prototype inhibitor of eukaryotic translation elongation. In the last three decades, a variety of natural products from different origins were discovered to also address the elongation step in different manners, including interference with the elongation factors eEF1 and eEF2 as well as binding to A-, P- or E-sites of the ribosome itself. Recent advances in the crystallization of the ribosomal machinery together with natural product inhibitors allowed characterizing similarities as well as differences in their mode of action. Since aberrations in protein synthesis are commonly observed in tumors, and malfunction or overexpression of translation factors can cause cellular transformation, the protein synthesis machinery has been realized as an attractive target for anticancer drugs. The therapeutic use of the first natural products that reached market approval, plitidepsin (Aplidin®) and homoharringtonine (Synribo®), will be introduced. In addition, we will highlight two other potential indications for translation elongation inhibitors, i.e. viral infections and genetic disorders caused by premature termination of translation.
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Affiliation(s)
- Mark Brönstrup
- Department of Chemical Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany. and Center of Biomolecular Drug Research (BMWZ), Leibniz University, 30159 Hannover, Germany and German Center for Infection Research (DZIF), partner site Hannover-Braunschweig, Germany
| | - Florenz Sasse
- Department of Chemical Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany.
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22
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Kador PF, Salvi R. Multifunctional Redox Modulators Protect Auditory, Visual, and Cognitive Function. Antioxid Redox Signal 2021; 36:1136-1157. [PMID: 34162214 PMCID: PMC9221172 DOI: 10.1089/ars.2021.0129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 06/18/2021] [Indexed: 12/26/2022]
Abstract
Significance: Oxidative stress contributes to vision, hearing and neurodegenerative disorders. Currently, no treatments prevent these disorders; therefore, there is an urgent need for redox modulators that can prevent these disorders. Recent Advances: Oxidative stress is associated with the generation of reactive oxygen species (ROS) and reactive nitrogen species, metal dyshomeostasis, and mitochondrial dysfunction. Here, we discuss the role that oxidative stress and metal dyshomeostasis play in hearing loss, visual impairments, and neurodegeneration and discuss the benefits of a new class of multifunctional redox modulators (MFRMs) that suppress sensory and neural degeneration. MFRMs not only reduce free radicals but also independently bind transition metals associated with the generation of hydroxyl radicals. The MFRMs redistribute zinc from neurotoxic amyloid beta zinc (Aβ:Zn) complexes to the cytoplasm, facilitating the degradation of Aβ plaques by matrix metalloprotease-2 (MMP-2). Although MFRMs bind copper (Cu1+, Cu2+), iron (Fe2+, Fe3+), zinc (Zn2+), and manganese (Mn2+), they do not deplete free cytoplasmic Zn+2 and they protect mitochondria from Mn+2-induced dysfunction. Oral administration of MFRMs reduce ROS-induced cataracts, protect the retina from light-induced degeneration, reduce neurotoxic Aβ:Zn plaque formation, and protect auditory hair cells from noise-induced hearing loss. Critical Issues: Regulation of redox balance is essential for clinical efficacy in maintaining sensory functions. Future Directions: Future use of these MFRMs requires additional pharmacokinetic, pharmacodynamics, and toxicological data to bring them into widespread clinical use. Additional animal studies are also needed to determine whether MFRMs can prevent neurodegeneration, dementia, and other forms of vision and hearing loss.
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Affiliation(s)
- Peter F. Kador
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, New York, USA
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23
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Effects of Moringa Extract on Aminoglycoside-Induced Hair Cell Death and Organ of Corti Damage. Otol Neurotol 2021; 42:1261-1268. [PMID: 34049329 DOI: 10.1097/mao.0000000000003193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
HYPOTHESIS Moringa extract, a naturally occurring anti-oxidant, protects against aminoglycoside-induced hair cell death and hearing loss within the organ of Corti. BACKGROUND Reactive oxygen species (ROS) arise primarily in the mitochondria and have been implicated in aminoglycoside-induced ototoxicity. Mitochondrial dysfunction results in loss of membrane potential, release of caspases, and cell apoptosis. Moringa extract has not previously been examined as a protective agent for aminoglycoside-induced ototoxicity. METHODS Putative otoprotective effects of moringa extract were investigated in an organotypic model using murine organ of Corti explants subjected to gentamicin-induced ototoxicity. Assays evaluated hair cell loss, cytochrome oxidase expression, mitochondrial membrane potential integrity, and caspase activity. RESULTS In vitro application of moringa conferred significant protection from gentamicin-induced hair cell loss at dosages from 25 to 300 μg/mL, with dosages above 100 μg/mL conferring near complete protection. Assays demonstrated moringa extract suppression of ROS, preservation of cytochrome oxidase activity, and reduction in caspase production. CONCLUSION Moringa extract demonstrated potent antioxidant properties with significant protection against gentamicin ototoxicity in cochlear explants.
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24
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Baradaran-Heravi A, Balgi AD, Hosseini-Farahabadi S, Choi K, Has C, Roberge M. Effect of small molecule eRF3 degraders on premature termination codon readthrough. Nucleic Acids Res 2021; 49:3692-3708. [PMID: 33764477 PMCID: PMC8053119 DOI: 10.1093/nar/gkab194] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/04/2021] [Accepted: 03/10/2021] [Indexed: 12/16/2022] Open
Abstract
Premature termination codon (PTC) readthrough is considered a potential treatment for genetic diseases caused by nonsense mutations. High concentrations of aminoglycosides induce low levels of PTC readthrough but also elicit severe toxicity. Identifying compounds that enhance PTC readthrough by aminoglycosides or reduce their toxicity is a continuing challenge. In humans, a binary complex of eukaryotic release factors 1 (eRF1) and 3 (eRF3a or eRF3b) mediates translation termination. They also participate in the SURF (SMG1-UPF1-eRF1-eRF3) complex assembly involved in nonsense-mediated mRNA decay (NMD). We show that PTC readthrough by aminoglycoside G418 is considerably enhanced by eRF3a and eRF3b siRNAs and cereblon E3 ligase modulators CC-885 and CC-90009, which induce proteasomal degradation of eRF3a and eRF3b. eRF3 degradation also reduces eRF1 levels and upregulates UPF1 and selectively stabilizes TP53 transcripts bearing a nonsense mutation over WT, indicating NMD suppression. CC-90009 is considerably less toxic than CC-885 and it enhances PTC readthrough in combination with aminoglycosides in mucopolysaccharidosis type I-Hurler, late infantile neuronal ceroid lipofuscinosis, Duchenne muscular dystrophy and junctional epidermolysis bullosa patient-derived cells with nonsense mutations in the IDUA, TPP1, DMD and COL17A1 genes, respectively. Combination of CC-90009 with aminoglycosides such as gentamicin or ELX-02 may have potential for PTC readthrough therapy.
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Affiliation(s)
- Alireza Baradaran-Heravi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Aruna D Balgi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Sara Hosseini-Farahabadi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Kunho Choi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Cristina Has
- Department of Dermatology, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Michel Roberge
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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Hosseini-Farahabadi S, Baradaran-Heravi A, Zimmerman C, Choi K, Flibotte S, Roberge M. Small molecule Y-320 stimulates ribosome biogenesis, protein synthesis, and aminoglycoside-induced premature termination codon readthrough. PLoS Biol 2021; 19:e3001221. [PMID: 33939688 PMCID: PMC8118496 DOI: 10.1371/journal.pbio.3001221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 05/13/2021] [Accepted: 04/09/2021] [Indexed: 11/18/2022] Open
Abstract
Premature termination codons (PTC) cause over 10% of genetic disease cases. Some aminoglycosides that bind to the ribosome decoding center can induce PTC readthrough and restore low levels of full-length functional proteins. However, concomitant inhibition of protein synthesis limits the extent of PTC readthrough that can be achieved by aminoglycosides like G418. Using a cell-based screen, we identified a small molecule, the phenylpyrazoleanilide Y-320, that potently enhances TP53, DMD, and COL17A1 PTC readthrough by G418. Unexpectedly, Y-320 increased cellular protein levels and protein synthesis, measured by SYPRO Ruby protein staining and puromycin labeling, as well as ribosome biogenesis measured using antibodies to rRNA and ribosomal protein S6. Y-320 did not increase the rate of translation elongation and it exerted its effects independently of mTOR signaling. At the single cell level, exposure to Y-320 and G418 increased ribosome content and protein synthesis which correlated strongly with PTC readthrough. As a single agent, Y-320 did not affect translation fidelity measured using a luciferase reporter gene but it enhanced misincorporation by G418. RNA-seq data showed that Y-320 up-regulated the expression of CXC chemokines CXCL10, CXCL8, CXCL2, CXCL11, CXCL3, CXCL1, and CXCL16. Several of these chemokines exert their cellular effects through the receptor CXCR2 and the CXCR2 antagonist SB225002 reduced cellular protein levels and PTC readthrough in cells exposed to Y-320 and G418. These data show that the self-limiting nature of PTC readthrough by G418 can be compensated by Y-320, a potent enhancer of PTC readthrough that increases ribosome biogenesis and protein synthesis. They also support a model whereby increased PTC readthrough is enabled by increased protein synthesis mediated by an autocrine chemokine signaling pathway. The findings also raise the possibility that inflammatory processes affect cellular propensity to readthrough agents and that immunomodulatory drugs like Y-320 might find application in PTC readthrough therapy.
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Affiliation(s)
- Sara Hosseini-Farahabadi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alireza Baradaran-Heravi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Carla Zimmerman
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kunho Choi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephane Flibotte
- UBC/LSI Bioinformatics Facility, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michel Roberge
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
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26
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Translation error clusters induced by aminoglycoside antibiotics. Nat Commun 2021; 12:1830. [PMID: 33758186 PMCID: PMC7987974 DOI: 10.1038/s41467-021-21942-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 02/08/2021] [Indexed: 02/04/2023] Open
Abstract
Aminoglycoside antibiotics target the ribosome and induce mistranslation, yet which translation errors induce bacterial cell death is unclear. The analysis of cellular proteins by quantitative mass spectrometry shows that bactericidal aminoglycosides induce not only single translation errors, but also clusters of errors in full-length proteins in vivo with as many as four amino acid substitutions in a row. The downstream errors in a cluster are up to 10,000-fold more frequent than the first error and independent of the intracellular aminoglycoside concentration. The prevalence, length, and composition of error clusters depends not only on the misreading propensity of a given aminoglycoside, but also on its ability to inhibit ribosome translocation along the mRNA. Error clusters constitute a distinct class of misreading events in vivo that may provide the predominant source of proteotoxic stress at low aminoglycoside concentration, which is particularly important for the autocatalytic uptake of the drugs. Aminoglycoside antibiotics target the ribosome and induce misreading, yet which translation errors induce bacterial cell death is unclear. Here authors use quantitative mass spectrometry and show that bactericidal aminoglycosides induce clusters of errors in full-length proteins in vivo with as many as four amino acid substitutions in a row.
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Dalhoff A. Selective toxicity of antibacterial agents-still a valid concept or do we miss chances and ignore risks? Infection 2021; 49:29-56. [PMID: 33367978 PMCID: PMC7851017 DOI: 10.1007/s15010-020-01536-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 10/04/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Selective toxicity antibacteribiotics is considered to be due to interactions with targets either being unique to bacteria or being characterized by a dichotomy between pro- and eukaryotic pathways with high affinities of agents to bacterial- rather than eukaryotic targets. However, the theory of selective toxicity oversimplifies the complex modes of action of antibiotics in pro- and eukaryotes. METHODS AND OBJECTIVE This review summarizes data describing multiple modes of action of antibiotics in eukaryotes. RESULTS Aminoglycosides, macrolides, oxazolidinones, chloramphenicol, clindamycin, tetracyclines, glycylcyclines, fluoroquinolones, rifampicin, bedaquillin, ß-lactams inhibited mitochondrial translation either due to binding to mitosomes, inhibition of mitochondrial RNA-polymerase-, topoisomerase 2ß-, ATP-synthesis, transporter activities. Oxazolidinones, tetracyclines, vancomycin, ß-lactams, bacitracin, isoniazid, nitroxoline inhibited matrix-metalloproteinases (MMP) due to chelation with zinc and calcium, whereas fluoroquinols fluoroquinolones and chloramphenicol chelated with these cations, too, but increased MMP activities. MMP-inhibition supported clinical efficacies of ß-lactams and daptomycin in skin-infections, and of macrolides, tetracyclines in respiratory-diseases. Chelation may have contributed to neuroprotection by ß-lactams and fluoroquinolones. Aminoglycosides, macrolides, chloramphenicol, oxazolidins oxazolidinones, tetracyclines caused read-through of premature stop codons. Several additional targets for antibiotics in human cells have been identified like interaction of fluoroquinolones with DNA damage repair in eukaryotes, or inhibition of mucin overproduction by oxazolidinones. CONCLUSION The effects of antibiotics on eukaryotes are due to identical mechanisms as their antibacterial activities because of structural and functional homologies of pro- and eukaryotic targets, so that the effects of antibiotics on mammals are integral parts of their overall mechanisms of action.
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Affiliation(s)
- Axel Dalhoff
- Christian-Albrechts-University of Kiel, Institue for Infection Medicine, Brunswiker Str. 4, D-24105, Kiel, Germany.
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28
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Cavinato M, Madreiter-Sokolowski CT, Büttner S, Schosserer M, Zwerschke W, Wedel S, Grillari J, Graier WF, Jansen-Dürr P. Targeting cellular senescence based on interorganelle communication, multilevel proteostasis, and metabolic control. FEBS J 2020; 288:3834-3854. [PMID: 33200494 PMCID: PMC7611050 DOI: 10.1111/febs.15631] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 11/02/2020] [Accepted: 11/13/2020] [Indexed: 02/06/2023]
Abstract
Cellular senescence, a stable cell division arrest caused by severe damage and stress, is a hallmark of aging in vertebrates including humans. With progressing age, senescent cells accumulate in a variety of mammalian tissues, where they contribute to tissue aging, identifying cellular senescence as a major target to delay or prevent aging. There is an increasing demand for the discovery of new classes of small molecules that would either avoid or postpone cellular senescence by selectively eliminating senescent cells from the body (i.e., ‘senolytics’) or inactivating/switching damage‐inducing properties of senescent cells (i.e., ‘senostatics/senomorphics’), such as the senescence‐associated secretory phenotype. Whereas compounds with senolytic or senostatic activity have already been described, their efficacy and specificity has not been fully established for clinical use yet. Here, we review mechanisms of senescence that are related to mitochondria and their interorganelle communication, and the involvement of proteostasis networks and metabolic control in the senescent phenotype. These cellular functions are associated with cellular senescence in in vitro and in vivo models but have not been fully exploited for the search of new compounds to counteract senescence yet. Therefore, we explore possibilities to target these mechanisms as new opportunities to selectively eliminate and/or disable senescent cells with the aim of tissue rejuvenation. We assume that this research will provide new compounds from the chemical space which act as mimetics of caloric restriction, modulators of calcium signaling and mitochondrial physiology, or as proteostasis optimizers, bearing the potential to counteract cellular senescence, thereby allowing healthy aging.
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Affiliation(s)
- Maria Cavinato
- Institute for Biomedical Aging Research, Leopold-Franzens Universität Innsbruck, Austria.,Center for Molecular Biosciences Innsbruck (CMBI), Leopold-Franzens Universität Innsbruck, Austria
| | - Corina T Madreiter-Sokolowski
- Department of Health Sciences and Technology, Institute of Translational Medicine, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland.,Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Austria
| | - Sabrina Büttner
- Institute of Molecular Biosciences, University of Graz, Austria.,Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Sweden
| | - Markus Schosserer
- Christian Doppler Laboratory for Skin Multimodal Analytical Imaging of Aging and Senescence, Institute of Molecular Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Austrian Cluster for Tissue Regeneration, Medical University of Vienna, Austria
| | - Werner Zwerschke
- Institute for Biomedical Aging Research, Leopold-Franzens Universität Innsbruck, Austria.,Center for Molecular Biosciences Innsbruck (CMBI), Leopold-Franzens Universität Innsbruck, Austria
| | - Sophia Wedel
- Institute for Biomedical Aging Research, Leopold-Franzens Universität Innsbruck, Austria.,Center for Molecular Biosciences Innsbruck (CMBI), Leopold-Franzens Universität Innsbruck, Austria
| | - Johannes Grillari
- Christian Doppler Laboratory for Skin Multimodal Analytical Imaging of Aging and Senescence, Institute of Molecular Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Austrian Cluster for Tissue Regeneration, Medical University of Vienna, Austria.,Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria
| | - Wolfgang F Graier
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Austria.,BioTechMed Graz, Austria
| | - Pidder Jansen-Dürr
- Institute for Biomedical Aging Research, Leopold-Franzens Universität Innsbruck, Austria.,Center for Molecular Biosciences Innsbruck (CMBI), Leopold-Franzens Universität Innsbruck, Austria
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Dissociating antibacterial from ototoxic effects of gentamicin C-subtypes. Proc Natl Acad Sci U S A 2020; 117:32423-32432. [PMID: 33288712 DOI: 10.1073/pnas.2013065117] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Gentamicin is a potent broad-spectrum aminoglycoside antibiotic whose use is hampered by ototoxic side-effects. Hospital gentamicin is a mixture of five gentamicin C-subtypes and several impurities of various ranges of nonexact concentrations. We developed a purification strategy enabling assaying of individual C-subtypes and impurities for ototoxicity and antimicrobial activity. We found that C-subtypes displayed broad and potent in vitro antimicrobial activities comparable to the hospital gentamicin mixture. In contrast, they showed different degrees of ototoxicity in cochlear explants, with gentamicin C2b being the least and gentamicin C2 the most ototoxic. Structure-activity relationships identified sites in the C4'-C6' region on ring I that reduced ototoxicity while preserving antimicrobial activity, thus identifying targets for future drug design and mechanisms for hair cell toxicity. Structure-activity relationship data suggested and electrophysiological data showed that the C-subtypes both bind and permeate the hair cell mechanotransducer channel, with the stronger the binding the less ototoxic the compound. Finally, both individual and reformulated mixtures of C-subtypes demonstrated decreased ototoxicity while maintaining antimicrobial activity, thereby serving as a proof-of-concept of drug reformulation to minimizing ototoxicity of gentamicin in patients.
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30
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Tokhmafshan F, Dickinson K, Akpa MM, Brasell E, Huertas P, Goodyer PR. A no-nonsense approach to hereditary kidney disease. Pediatr Nephrol 2020; 35:2031-2042. [PMID: 31807928 DOI: 10.1007/s00467-019-04394-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 07/05/2019] [Accepted: 10/07/2019] [Indexed: 01/12/2023]
Abstract
The advent of a new class of aminoglycosides with increased translational readthrough of nonsense mutations and reduced toxicity offers a new therapeutic strategy for a subset of patients with hereditary kidney disease. The renal uptake and retention of aminoglycosides at a high intracellular concentration makes the kidney an ideal target for this approach. In this review, we explore the potential of aminoglycoside readthrough therapy in a number of hereditary kidney diseases and discuss the therapeutic window of opportunity for subclasses of each disease, when caused by nonsense mutations.
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Affiliation(s)
- Fatima Tokhmafshan
- Research Institute of the McGill University Health Center, 1001 Décarie Boulevard, EM1.2232, Montreal, QC, H4A 3J1, Canada
| | - Kyle Dickinson
- Research Institute of the McGill University Health Center, 1001 Décarie Boulevard, EM1.2232, Montreal, QC, H4A 3J1, Canada.,Department of Experimental Medicine, McGill University, Montreal, Canada
| | - Murielle M Akpa
- Research Institute of the McGill University Health Center, 1001 Décarie Boulevard, EM1.2232, Montreal, QC, H4A 3J1, Canada
| | - Emma Brasell
- Department of Human Genetics, McGill University, Montreal, Canada
| | | | - Paul R Goodyer
- Research Institute of the McGill University Health Center, 1001 Décarie Boulevard, EM1.2232, Montreal, QC, H4A 3J1, Canada. .,Department of Experimental Medicine, McGill University, Montreal, Canada. .,Department of Human Genetics, McGill University, Montreal, Canada. .,Department of Pediatrics, McGill University, Montreal, Canada.
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31
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Palma M, Lejeune F. Deciphering the molecular mechanism of stop codon readthrough. Biol Rev Camb Philos Soc 2020; 96:310-329. [PMID: 33089614 DOI: 10.1111/brv.12657] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 09/23/2020] [Accepted: 09/26/2020] [Indexed: 12/11/2022]
Abstract
Recognition of the stop codon by the translation machinery is essential to terminating translation at the right position and to synthesizing a protein of the correct size. Under certain conditions, the stop codon can be recognized as a coding codon promoting translation, which then terminates at a later stop codon. This event, called stop codon readthrough, occurs either by error, due to a dedicated regulatory environment leading to generation of different protein isoforms, or through the action of a readthrough compound. This review focuses on the mechanisms of stop codon readthrough, the nucleotide and protein environments that facilitate or inhibit it, and the therapeutic interest of stop codon readthrough in the treatment of genetic diseases caused by nonsense mutations.
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Affiliation(s)
- Martine Palma
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, UMR9020 - U1277 - CANTHER - Cancer Heterogeneity Plasticity and Resistance to Therapies, F-59000 Lille, France
| | - Fabrice Lejeune
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, UMR9020 - U1277 - CANTHER - Cancer Heterogeneity Plasticity and Resistance to Therapies, F-59000 Lille, France
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32
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Kerem E. ELX-02: an investigational read-through agent for the treatment of nonsense mutation-related genetic disease. Expert Opin Investig Drugs 2020; 29:1347-1354. [DOI: 10.1080/13543784.2020.1828862] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Eitan Kerem
- Department of Pediatrics and CF Center, Hadassah Hebrew University Medical Center, Jerusalem, Israel
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33
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Idowu T, Ammeter D, Brizuela M, Jackson G, Alam S, Schweizer F. Overcoming β-Lactam resistance in Pseudomonas aeruginosa using non-canonical tobramycin-based antibiotic adjuvants. Bioorg Med Chem Lett 2020; 30:127575. [PMID: 32980511 DOI: 10.1016/j.bmcl.2020.127575] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 12/18/2022]
Abstract
β-Lactam antibiotics have for long been a mainstay in antimicrobial chemotherapy. However, due to its ubiquitous usage, bacteria have evolved multiple concerted pathways to evade its actions, underscoring the complexity of resistance to this class of drug. Current strategies to mitigate this problem are geared towards developing inhibitors that can shield the β-lactam core from enzymatic hydrolysis. In reality, a combination of factors including porin loss, overexpressed efflux pumps, expression of β-lactamases, reduced outer membrane permeability, and target modifications are characteristics of phenotypes that are microbiologically resistant to β-lactam antibiotics, especially Pseudomonas aeruginosa. Herein, we describe a strategy that may simultaneously address multiple mechanisms of resistance to β-lactams. A triple combination with β-lactam/β-lactamase inhibitors offers better microbiological response against carbapenem-resistant P. aeruginosa than the current standard of care. The observed interactions are also unaffected by efflux pumps. We conclude that a multicomponent combination therapy may be the way forward in addressing the myriads of emerging therapy failure associated with β-lactam resistance.
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Affiliation(s)
- Temilolu Idowu
- Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Derek Ammeter
- Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Marc Brizuela
- Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Gregory Jackson
- Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Shadman Alam
- Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Frank Schweizer
- Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2, Canada; Department of Medical Microbiology/Infectious Diseases, University of Manitoba, Winnipeg, MB R3T 1R9, Canada.
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Sensing through Non-Sensing Ocular Ion Channels. Int J Mol Sci 2020; 21:ijms21186925. [PMID: 32967234 PMCID: PMC7554890 DOI: 10.3390/ijms21186925] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/12/2022] Open
Abstract
Ion channels are membrane-spanning integral proteins expressed in multiple organs, including the eye. In the eye, ion channels are involved in various physiological processes, like signal transmission and visual processing. A wide range of mutations have been reported in the corresponding genes and their interacting subunit coding genes, which contribute significantly to an array of blindness, termed ocular channelopathies. These mutations result in either a loss- or gain-of channel functions affecting the structure, assembly, trafficking, and localization of channel proteins. A dominant-negative effect is caused in a few channels formed by the assembly of several subunits that exist as homo- or heteromeric proteins. Here, we review the role of different mutations in switching a “sensing” ion channel to “non-sensing,” leading to ocular channelopathies like Leber’s congenital amaurosis 16 (LCA16), cone dystrophy, congenital stationary night blindness (CSNB), achromatopsia, bestrophinopathies, retinitis pigmentosa, etc. We also discuss the various in vitro and in vivo disease models available to investigate the impact of mutations on channel properties, to dissect the disease mechanism, and understand the pathophysiology. Innovating the potential pharmacological and therapeutic approaches and their efficient delivery to the eye for reversing a “non-sensing” channel to “sensing” would be life-changing.
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35
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Wang K, Romm EL, Kouznetsova VL, Tsigelny IF. Prediction of Premature Termination Codon Suppressing Compounds for Treatment of Duchenne Muscular Dystrophy Using Machine Learning. Molecules 2020; 25:molecules25173886. [PMID: 32858918 PMCID: PMC7503396 DOI: 10.3390/molecules25173886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/14/2020] [Accepted: 08/20/2020] [Indexed: 11/16/2022] Open
Abstract
A significant percentage of Duchenne muscular dystrophy (DMD) cases are caused by premature termination codon (PTC) mutations in the dystrophin gene, leading to the production of a truncated, non-functional dystrophin polypeptide. PTC-suppressing compounds (PTCSC) have been developed in order to restore protein translation by allowing the incorporation of an amino acid in place of a stop codon. However, limitations exist in terms of efficacy and toxicity. To identify new compounds that have PTC-suppressing ability, we selected and clustered existing PTCSC, allowing for the construction of a common pharmacophore model. Machine learning (ML) and deep learning (DL) models were developed for prediction of new PTCSC based on known compounds. We conducted a search of the NCI compounds database using the pharmacophore-based model and a search of the DrugBank database using pharmacophore-based, ML and DL models. Sixteen drug compounds were selected as a consensus of pharmacophore-based, ML, and DL searches. Our results suggest notable correspondence of the pharmacophore-based, ML, and DL models in prediction of new PTC-suppressing compounds.
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Affiliation(s)
- Kate Wang
- MAP program, University of California San Diego (UCSD), La Jolla, CA 92093, USA;
| | - Eden L. Romm
- Curematch Inc., 6440 Lusk Blvd, Suite D206, San Diego, CA 92121, USA;
| | - Valentina L. Kouznetsova
- San Diego Supercomputer Center, University of California San Diego (UCSD), La Jolla, CA 92093, USA;
| | - Igor F. Tsigelny
- Curematch Inc., 6440 Lusk Blvd, Suite D206, San Diego, CA 92121, USA;
- San Diego Supercomputer Center, University of California San Diego (UCSD), La Jolla, CA 92093, USA;
- Dept. of Neurosciences, University of California San Diego (UCSD), La Jolla, CA 92093, USA
- Correspondence:
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36
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RNA-targeted drug discovery: moving beyond promiscuous small-molecule scaffolds. Future Med Chem 2020; 11:2487-2490. [PMID: 31633403 DOI: 10.4155/fmc-2019-0200] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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37
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Sharma J, Keeling KM, Rowe SM. Pharmacological approaches for targeting cystic fibrosis nonsense mutations. Eur J Med Chem 2020; 200:112436. [PMID: 32512483 DOI: 10.1016/j.ejmech.2020.112436] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/04/2020] [Accepted: 05/06/2020] [Indexed: 12/11/2022]
Abstract
Cystic fibrosis (CF) is a monogenic autosomal recessive disorder. The clinical manifestations of the disease are caused by ∼2,000 mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) protein. It is unlikely that any one approach will be efficient in correcting all defects. The recent approvals of ivacaftor, lumacaftor/ivacaftor and elexacaftor/tezacaftor/ivacaftor represent the genesis of a new era of precision combination medicine for the CF patient population. In this review, we discuss targeted translational readthrough approaches as mono and combination therapies for CFTR nonsense mutations. We examine the current status of efficacy of translational readthrough/nonsense suppression therapies and their limitations, including non-native amino acid incorporation at PTCs and nonsense-mediated mRNA decay (NMD), along with approaches to tackle these limitations. We further elaborate on combining various therapies such as readthrough agents, NMD inhibitors, and corrector/potentiators to improve the efficacy and safety of suppression therapy. These mutation specific strategies that are directed towards the basic CF defects should positively impact CF patients bearing nonsense mutations.
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Affiliation(s)
- Jyoti Sharma
- Department of Medicine, University of Alabama at Birmingham (UAB), USA; Department of Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), USA
| | - Kim M Keeling
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham (UAB), USA; Department of Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), USA
| | - Steven M Rowe
- Department of Medicine, University of Alabama at Birmingham (UAB), USA; Department of Pediatrics, University of Alabama at Birmingham (UAB), USA; Department of Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham (UAB), USA.
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Crawford DK, Alroy I, Sharpe N, Goddeeris MM, Williams G. ELX-02 Generates Protein via Premature Stop Codon Read-Through without Inducing Native Stop Codon Read-Through Proteins. J Pharmacol Exp Ther 2020; 374:264-272. [PMID: 32376628 DOI: 10.1124/jpet.120.265595] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 04/30/2020] [Indexed: 12/17/2022] Open
Abstract
ELX-02 is a clinical stage, small-molecule eukaryotic ribosomal selective glycoside acting to induce read-through of premature stop codons (PSCs) that results in translation of full-length protein. However, improved read-through at PSCs has raised the question of whether native stop codon (NSC) fidelity would be impacted. Here, we compare read-through by ELX-02 in PSC and NSC contexts. DMS-114 cells containing a PSC in the TP53 gene were treated with ELX-02 and tested for increased nuclear p53 protein expression while also monitoring two other proteins for NSC read-through. Additionally, blood samples were taken from healthy subjects pre- and post-treatment with ELX-02 (0.3-7.5 mg/kg). These samples were processed to collect white blood cells and then analyzed by western blot to identify native and potentially elongated proteins from NSC read-through. In a separate experiment, lymphocytes cultivated with vehicle or ELX-02 (20 and 100 μg/ml) were subjected to proteomic analysis. We found that ELX-02 produced significant read-through of the PSC found in TP53 mRNA in DMS-114 cells, resulting in increased p53 protein expression and consistent with decreased nonsense-mediated mRNA degradation. NSC read-through protein products were not observed in either DMS-114 cells or in clinical samples from subjects dosed with ELX-02. The number of read-through proteins identified by using proteomic analysis was lower than estimated, and none of the NSC read-through products identified with >2 peptides showed dose-dependent responses to ELX-02. Our results demonstrate significant PSC read-through by ELX-02 with maintained NSC fidelity, thus supporting the therapeutic utility of ELX-02 in diseases resulting from nonsense alleles. SIGNIFICANCE STATEMENT: ELX-02 produces significant read-through of premature stop codons leading to full-length functional protein, demonstrated here by using the R213X mutation in the TP53 gene of DMS-114 cells. In addition, three complementary techniques suggest that ELX-02 does not promote read-through of native stop codons at concentrations that lead to premature stop codon read-through. Thus, ELX-02 may be a potential therapeutic option for nonsense mutation-mediated genetic diseases.
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Affiliation(s)
| | - Iris Alroy
- Eloxx Pharmaceuticals, Inc., Waltham, Massachusetts
| | - Neal Sharpe
- Eloxx Pharmaceuticals, Inc., Waltham, Massachusetts
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Way CM, Lima Cunha D, Moosajee M. Translational readthrough inducing drugs for the treatment of inherited retinal dystrophies. EXPERT REVIEW OF OPHTHALMOLOGY 2020. [DOI: 10.1080/17469899.2020.1762489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Christopher M Way
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK
| | - Dulce Lima Cunha
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK
| | - Mariya Moosajee
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
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2,6-Diaminopurine as a highly potent corrector of UGA nonsense mutations. Nat Commun 2020; 11:1509. [PMID: 32198346 PMCID: PMC7083880 DOI: 10.1038/s41467-020-15140-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 02/21/2020] [Indexed: 12/21/2022] Open
Abstract
Nonsense mutations cause about 10% of genetic disease cases, and no treatments are available. Nonsense mutations can be corrected by molecules with nonsense mutation readthrough activity. An extract of the mushroom Lepista inversa has recently shown high-efficiency correction of UGA and UAA nonsense mutations. One active constituent of this extract is 2,6-diaminopurine (DAP). In Calu-6 cancer cells, in which TP53 gene has a UGA nonsense mutation, DAP treatment increases p53 level. It also decreases the growth of tumors arising from Calu-6 cells injected into immunodeficient nude mice. DAP acts by interfering with the activity of a tRNA-specific 2′-O-methyltransferase (FTSJ1) responsible for cytosine 34 modification in tRNATrp. Low-toxicity and high-efficiency UGA nonsense mutation correction make DAP a good candidate for the development of treatments for genetic diseases caused by nonsense mutations. Nonsense mutations can be corrected by several molecules that activate readthrough of premature termination codon. Here, the authors report that 2,6-diaminopurine efficiently corrects UGA nonsense mutations with no significant toxicity.
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A Dimer, but Not Monomer, of Tobramycin Potentiates Ceftolozane against Multidrug-Resistant and Extensively Drug-Resistant Pseudomonas aeruginosa and Delays Resistance Development. Antimicrob Agents Chemother 2020; 64:AAC.02055-19. [PMID: 31907191 DOI: 10.1128/aac.02055-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 01/01/2020] [Indexed: 12/11/2022] Open
Abstract
Ceftolozane-tazobactam is a potent β-lactam/β-lactamase inhibitor combination approved for the treatment of complicated intraabdominal and complicated urinary tract infections and, more recently, the treatment of hospital-acquired and ventilator-associated bacterial pneumonia. Although the activities of ceftolozane are not enhanced by tazobactam against Pseudomonas aeruginosa, it remains the most potent antipseudomonal agent approved to date. Emerging data worldwide has included reports of microbiological failure in patients with serious bacterial infections caused by multidrug-resistant (MDR) P. aeruginosa as a result of ceftolozane resistance developed within therapy. The objective of this study is to compare the efficacy of a tobramycin homodimer plus ceftolozane versus ceftolozane-tazobactam alone against MDR and extensively drug-resistant (XDR) P. aeruginosa Tobramycin homodimer, a synthetic dimer of two monomeric units of tobramycin, was developed to abrogate the ribosomal properties of tobramycin with a view to mitigating aminoglycoside-related toxicity and resistance. Herein, we report that tobramycin homodimer, a nonribosomal aminoglycoside derivative, potentiates the activities of ceftolozane versus MDR/XDR P. aeruginosa in vitro and delays the emergence of resistance to ceftolozane-tazobactam in the wild-type PAO1 strain. This combination is also more potent than a standard ceftazidime-avibactam combination against these isolates. Conversely, a tobramycin monomer with intrinsic ribosomal properties does not potentiate ceftolozane under similar conditions. Susceptibility and checkerboard studies were assessed using serial 2-fold dilution assays, following the Clinical and Laboratory Standards Institute (CLSI) guidelines. This strategy provides an avenue to further preserve the clinical utility of ceftolozane and enhances its spectrum of activity against one of the most difficult-to-treat pathogens in hospitals.
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Zada SL, Baruch BB, Simhaev L, Engel H, Fridman M. Chemical Modifications Reduce Auditory Cell Damage Induced by Aminoglycoside Antibiotics. J Am Chem Soc 2020; 142:3077-3087. [PMID: 31958945 DOI: 10.1021/jacs.9b12420] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Although aminoglycoside antibiotics are effective against Gram-negative infections, these drugs often cause irreversible hearing damage. Binding to the decoding site of the eukaryotic ribosomes appears to result in ototoxicity, but there is evidence that other effects are involved. Here, we show how chemical modifications of apramycin and geneticin, considered among the least and most toxic aminoglycosides, respectively, reduce auditory cell damage. Using molecular dynamics simulations, we studied how modified aminoglycosides influence the essential freedom of movement of the decoding site of the ribosome, the region targeted by aminoglycosides. By determining the ratio of a protein translated in mitochondria to that of a protein translated in the cytoplasm, we showed that aminoglycosides can paradoxically elevate rather than reduce protein levels. We showed that certain aminoglycosides induce rapid plasma membrane permeabilization and that this nonribosomal effect can also be reduced through chemical modifications. The results presented suggest a new paradigm for the development of safer aminoglycoside antibiotics.
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Affiliation(s)
- Sivan Louzoun Zada
- School of Chemistry, Raymond and Beverley Sackler Faculty of Exact Sciences , Tel Aviv University , Tel Aviv , Israel , 6997801
| | - Bar Ben Baruch
- School of Chemistry, Raymond and Beverley Sackler Faculty of Exact Sciences , Tel Aviv University , Tel Aviv , Israel , 6997801
| | - Luba Simhaev
- Blavatnik Center for Drug Discovery , Tel Aviv University , Tel Aviv , 6997801 , Israel
| | - Hamutal Engel
- Blavatnik Center for Drug Discovery , Tel Aviv University , Tel Aviv , 6997801 , Israel
| | - Micha Fridman
- School of Chemistry, Raymond and Beverley Sackler Faculty of Exact Sciences , Tel Aviv University , Tel Aviv , Israel , 6997801
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Ban YH, Song MC, Park JW, Yoon YJ. Minor components of aminoglycosides: recent advances in their biosynthesis and therapeutic potential. Nat Prod Rep 2020; 37:301-311. [DOI: 10.1039/c9np00041k] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
This Highlight covers the recent advances in the biosynthetic pathways of aminoglycosides including their minor components, together with the therapeutic potential for minor aminoglycoside components and semi-synthetic aminoglycosides.
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Affiliation(s)
- Yeon Hee Ban
- Department of Chemistry and Nanoscience
- Ewha Womans University
- Seoul 03760
- Republic of Korea
| | - Myoung Chong Song
- Department of Chemistry and Nanoscience
- Ewha Womans University
- Seoul 03760
- Republic of Korea
| | - Je Won Park
- School of Biosystems and Biomedical Sciences
- Korea University
- Seoul 02841
- Republic of Korea
| | - Yeo Joon Yoon
- Department of Chemistry and Nanoscience
- Ewha Womans University
- Seoul 03760
- Republic of Korea
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Brasell EJ, Chu LL, Akpa MM, Eshkar-Oren I, Alroy I, Corsini R, Gilfix BM, Yamanaka Y, Huertas P, Goodyer P. The novel aminoglycoside, ELX-02, permits CTNSW138X translational read-through and restores lysosomal cystine efflux in cystinosis. PLoS One 2019; 14:e0223954. [PMID: 31800572 PMCID: PMC6892560 DOI: 10.1371/journal.pone.0223954] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 10/02/2019] [Indexed: 12/19/2022] Open
Abstract
Background Cystinosis is a rare disorder caused by recessive mutations of the CTNS gene. Current therapy decreases cystine accumulation, thus slowing organ deterioration without reversing renal Fanconi syndrome or preventing eventual need for a kidney transplant.15-20% of cystinosis patients harbour at least one nonsense mutation in CTNS, leading to premature end of translation of the transcript. Aminoglycosides have been shown to permit translational read-through but have high toxicity level, especially in the kidney and inner ear. ELX-02, a modified aminoglycoside, retains it read-through ability without the toxicity. Methods and findings We ascertained the toxicity of ELX-02 in cells and in mice as well as the effect of ELX-02 on translational read-through of nonsense mutations in cystinotic mice and human cells. ELX-02 was not toxic in vitro or in vivo, and permitted read-through of nonsense mutations in cystinotic mice and human cells. Conclusions ELX-02 has translational read-through activity and produces a functional CTNS protein, as evidenced by reduced cystine accumulation. This reduction is comparable to cysteamine treatment. ELX-02 accumulates in the kidney but neither cytotoxicity nor nephrotoxicity was observed.
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Affiliation(s)
- Emma J. Brasell
- McGill University, Department of Human Genetics, Montreal, Canada
| | - Lee Lee Chu
- Research Institute of the McGill University Health Centre, Montreal, Canada
| | - Murielle M. Akpa
- Research Institute of the McGill University Health Centre, Montreal, Canada
| | - Idit Eshkar-Oren
- McGill University, Department of Experimental Medicine, Montreal, Canada
| | - Iris Alroy
- McGill University, Department of Experimental Medicine, Montreal, Canada
| | - Rachel Corsini
- Research Institute of the McGill University Health Centre, Montreal, Canada
| | - Brian M. Gilfix
- Research Institute of the McGill University Health Centre, Montreal, Canada
| | - Yojiro Yamanaka
- McGill University, Department of Human Genetics, Montreal, Canada
| | - Pedro Huertas
- McGill University, Department of Experimental Medicine, Montreal, Canada
| | - Paul Goodyer
- McGill University, Department of Human Genetics, Montreal, Canada
- Research Institute of the McGill University Health Centre, Montreal, Canada
- Montreal Children’s Hospital, Department of Nephrology, Montreal, Canada
- Eloxx Pharmaceuticals, Inc., Waltham, United States of America
- * E-mail:
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Serum starvation enhances nonsense mutation readthrough. J Mol Med (Berl) 2019; 97:1695-1710. [PMID: 31786671 DOI: 10.1007/s00109-019-01847-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 10/03/2019] [Accepted: 10/23/2019] [Indexed: 12/13/2022]
Abstract
Of all genetic mutations causing human disease, premature termination codons (PTCs) that result from splicing defaults, insertions, deletions, and point mutations comprise around 30%. From these mutations, around 11% are a substitution of a single nucleotide that change a codon into a premature termination codon. These types of mutations affect several million patients suffering from a large variety of genetic diseases, ranging from relatively common inheritable cancer syndromes to muscular dystrophy or very rare neuro-metabolic disorders. Over the past three decades, genetic and biochemical studies have revealed that certain antibiotics and other synthetic molecules can act as nonsense mutation readthrough-inducing drugs. These compounds bind a specific site on the rRNA and, as a result, the stop codon is misread and an amino acid (that may or may not differ from the wild-type amino acid) is inserted and translation occurs through the premature termination codon. This strategy has great therapeutic potential. Unfortunately, many readthrough agents are toxic and cannot be administered over the extended period usually required for the chronic treatment of genetic diseases. Furthermore, readthrough compounds only restore protein production in very few disease models and the readthrough levels are usually low, typically achieving no more than 5% of normal protein expression. Efforts have been made over the years to overcome these obstacles so that readthrough treatment can become clinically relevant. Here, we present the creation of a stable cell line system that constitutively expresses our dual-reporter vector harboring two cancer initiating nonsense mutations in the adenomatous polyposis coli (APC) gene. This system will be used as an improved screening method for isolation of new nonsense mutation readthrough inducers. Using these cell lines as well as colorectal cancer cell lines, we demonstrate that serum starvation enhances drug-induced readthrough activity, an observation which may prove beneficial in a therapeutic scenario that requires higher levels of the restored protein. KEY MESSAGES: Nonsense mutations affects millions of people worldwide. We have developed a nonsense mutation read-through screening tool. We find that serum starvation enhances antibiotic-induced nonsense mutation read-through. Our results suggest new strategies for enhancing nonsense mutation read-through that may have positive effects on a large number of patients.
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Idowu T, Ammeter D, Rossong H, Zhanel GG, Schweizer F. Homodimeric Tobramycin Adjuvant Repurposes Novobiocin as an Effective Antibacterial Agent against Gram-Negative Bacteria. J Med Chem 2019; 62:9103-9115. [PMID: 31557020 DOI: 10.1021/acs.jmedchem.9b00876] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Low permeability across the outer membrane is a major reason why most antibiotics are ineffective against Gram-negative bacteria. Agents that permeabilize the outer membrane are typically toxic at their effective concentrations. Here, we report the development of a broad-spectrum homodimeric tobramycin adjuvant that is nontoxic and more potent than the gold standard permeabilizing agent, polymyxin B nonapeptide. In pilot studies, the adjuvant confers potent bactericidal activity on novobiocin against Gram-negative bacteria, including carbapenem-resistant and colistin-resistant strains bearing plasmid-borne mcr-1 genes. Resistance development to the combination was significantly reduced, relative to novobiocin alone, and there was no induction of cross-resistance to other antibiotics, including the gyrase-acting fluoroquinolones. Tobramycin homodimer may allow the use of lower doses of novobiocin, overcoming its twin problem of efficacy and toxicity.
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Affiliation(s)
- Temilolu Idowu
- Department of Chemistry , University of Manitoba , Winnipeg , MB R3T 2N2 , Canada
| | - Derek Ammeter
- Department of Chemistry , University of Manitoba , Winnipeg , MB R3T 2N2 , Canada
| | - Heather Rossong
- Department of Chemistry , University of Manitoba , Winnipeg , MB R3T 2N2 , Canada
| | - George G Zhanel
- Department of Medical Microbiology/Infectious Diseases , University of Manitoba , Winnipeg , MB R3T 1R9 , Canada
| | - Frank Schweizer
- Department of Chemistry , University of Manitoba , Winnipeg , MB R3T 2N2 , Canada.,Department of Medical Microbiology/Infectious Diseases , University of Manitoba , Winnipeg , MB R3T 1R9 , Canada
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Huang L, Aghajan M, Quesenberry T, Low A, Murray SF, Monia BP, Guo S. Targeting Translation Termination Machinery with Antisense Oligonucleotides for Diseases Caused by Nonsense Mutations. Nucleic Acid Ther 2019; 29:175-186. [PMID: 31070517 PMCID: PMC6686700 DOI: 10.1089/nat.2019.0779] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Efforts to develop treatments for diseases caused by nonsense mutations have focused on identification of small molecules that promote translational read-through of messenger RNAs (mRNAs) harboring nonsense stop codons to produce full-length proteins. However, to date, no small molecule read-through drug has received FDA approval, probably because of a lack of balance between efficacy and safety. Depletion of translation termination factors eukaryotic release factor (eRF) 1 and eRF3a in cells was shown to promote translational read-through of a luciferase reporter gene harboring a nonsense mutation. In this study, we identified antisense oligonucleotides (ASOs) targeting translation termination factors and determined if ASO-mediated depletion of these factors could be a potentially effective and safe therapeutic approach for diseases caused by nonsense mutations. We found that ASO-mediated reduction of either eRF1 or eRF3a to 30%–40% of normal levels in the mouse liver is well tolerated. Hemophilia mice that express a mutant allele of human coagulation factor IX (FIX) containing nonsense mutation R338X were treated with eRF1- or eRF3a-ASO. We found that although eRF1- or eRF3a-ASO alone only elicited a moderate read-through effect on hFIX-R338X mRNA, both worked in synergy with geneticin, a small molecule read-through drug, demonstrating significantly increased production of functional full-length hFIX protein to levels that would rescue disease phenotypes in these mice. Overall our results indicate that modulating the translation termination pathway in the liver by ASOs may provide a novel approach to improving the efficacy of small molecule read-through drugs to treat human genetic diseases caused by nonsense mutations.
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Affiliation(s)
- Lulu Huang
- Ionis Pharmaceuticals, Carlsbad, California
| | | | | | - Audrey Low
- Ionis Pharmaceuticals, Carlsbad, California
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48
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Lower ototoxicity and absence of hidden hearing loss point to gentamicin C1a and apramycin as promising antibiotics for clinical use. Sci Rep 2019; 9:2410. [PMID: 30787404 PMCID: PMC6382871 DOI: 10.1038/s41598-019-38634-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 11/29/2018] [Indexed: 11/08/2022] Open
Abstract
Spread of antimicrobial resistance and shortage of novel antibiotics have led to an urgent need for new antibacterials. Although aminoglycoside antibiotics (AGs) are very potent anti-infectives, their use is largely restricted due to serious side-effects, mainly nephrotoxicity and ototoxicity. We evaluated the ototoxicity of various AGs selected from a larger set of AGs on the basis of their strong antibacterial activities against multidrug-resistant clinical isolates of the ESKAPE panel: gentamicin, gentamicin C1a, apramycin, paromomycin and neomycin. Following local round window application, dose-dependent effects of AGs on outer hair cell survival and compound action potentials showed gentamicin C1a and apramycin as the least toxic. Strikingly, although no changes were observed in compound action potential thresholds and outer hair cell survival following treatment with low concentrations of neomycin, gentamicin and paromomycin, the number of inner hair cell synaptic ribbons and the compound action potential amplitudes were reduced. This indication of hidden hearing loss was not observed with gentamicin C1a or apramycin at such concentrations. These findings identify the inner hair cells as the most vulnerable element to AG treatment, indicating that gentamicin C1a and apramycin are promising bases for the development of clinically useful antibiotics.
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Shahi PK, Hermans D, Sinha D, Brar S, Moulton H, Stulo S, Borys KD, Capowski E, Pillers DAM, Gamm DM, Pattnaik BR. Gene Augmentation and Readthrough Rescue Channelopathy in an iPSC-RPE Model of Congenital Blindness. Am J Hum Genet 2019; 104:310-318. [PMID: 30686507 DOI: 10.1016/j.ajhg.2018.12.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 12/21/2018] [Indexed: 12/11/2022] Open
Abstract
Pathogenic variants of the KCNJ13 gene are known to cause Leber congenital amaurosis (LCA16), an inherited pediatric blindness. KCNJ13 encodes the Kir7.1 subunit that acts as a tetrameric, inwardly rectifying potassium ion channel in the retinal pigment epithelium (RPE) to maintain ionic homeostasis and allow photoreceptors to encode visual information. We sought to determine whether genetic approaches might be effective in treating blindness arising from pathogenic variants in KCNJ13. We derived human induced pluripotent stem cell (hiPSC)-RPE cells from an individual carrying a homozygous c.158G>A (p.Trp53∗) pathogenic variant of KCNJ13. We performed biochemical and electrophysiology assays to confirm Kir7.1 function. We tested both small-molecule readthrough drug and gene-therapy approaches for this "disease-in-a-dish" approach. We found that the LCA16 hiPSC-RPE cells had normal morphology but did not express a functional Kir7.1 channel and were unable to demonstrate normal physiology. After readthrough drug treatment, the LCA16 hiPSC cells were hyperpolarized by 30 mV, and the Kir7.1 current was restored. Similarly, we rescued Kir7.1 channel function after lentiviral gene delivery to the hiPSC-RPE cells. In both approaches, Kir7.1 was expressed normally, and there was restoration of membrane potential and the Kir7.1 current. Loss-of-function variants of Kir7.1 are one cause of LCA. Using either readthrough therapy or gene augmentation, we rescued Kir7.1 channel function in iPSC-RPE cells derived from an affected individual. This supports the development of precision-medicine approaches for the treatment of clinical LCA16.
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Affiliation(s)
- Pawan K Shahi
- Division of Neonatology, Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706, USA; McPherson Eye Research, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Dalton Hermans
- Division of Neonatology, Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Divya Sinha
- McPherson Eye Research, University of Wisconsin-Madison, Madison, WI 53705, USA; Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Simran Brar
- Division of Neonatology, Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Hannah Moulton
- Division of Neonatology, Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Sabrina Stulo
- Division of Neonatology, Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Katarzyna D Borys
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Elizabeth Capowski
- McPherson Eye Research, University of Wisconsin-Madison, Madison, WI 53705, USA; Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - De-Ann M Pillers
- Division of Neonatology, Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706, USA; McPherson Eye Research, University of Wisconsin-Madison, Madison, WI 53705, USA; Medical Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - David M Gamm
- McPherson Eye Research, University of Wisconsin-Madison, Madison, WI 53705, USA; Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Bikash R Pattnaik
- Division of Neonatology, Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53706, USA; McPherson Eye Research, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI 53705, USA.
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Leubitz A, Frydman-Marom A, Sharpe N, van Duzer J, Campbell KCM, Vanhoutte F. Safety, Tolerability, and Pharmacokinetics of Single Ascending Doses of ELX-02, a Potential Treatment for Genetic Disorders Caused by Nonsense Mutations, in Healthy Volunteers. Clin Pharmacol Drug Dev 2019; 8:984-994. [PMID: 30650260 DOI: 10.1002/cpdd.647] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 12/03/2018] [Indexed: 12/13/2022]
Abstract
ELX-02 is an investigational synthetic eukaryotic ribosome-selective glycoside optimized as a translational read-through molecule that induces read through of nonsense mutations, resulting in normally localized full-length functional proteins. ELX-02 is being developed as a therapy for genetic diseases caused by nonsense mutations. Two phase 1a, randomized, double-blind placebo-controlled, single-ascending-dose studies were conducted in healthy human subjects to evaluate the safety and pharmacokinetics of ELX-02. Single subcutaneously injected doses of ELX-02 between 0.3 mg/kg and 7.5 mg/kg showed an acceptable safety profile without severe or serious drug-related adverse events, including a lack of renal and ototoxicity events. Injection of ELX-02 resulted in a rapid time to peak concentration and elimination phase, with complete elimination from the vascular compartment within 10 hours. ELX-02 area under the concentration-time curve to infinity showed dose-exposure linearity (24-fold increase for a 25-fold dose increase), and the maximum concentration showed dose proportionality (17-fold increase for a 25-fold increase). The mean apparent volume of distribution was dose dependent, suggesting an increased distribution and tissue uptake of ELX-02 at higher doses. The primary route of excretion was in the urine, with the majority of the compound excreted unchanged. These results support the evaluation of the safety, pharmacokinetics, and efficacy of repeat dosing in future studies.
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