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Camici M, Garcia-Gil M, Allegrini S, Pesi R, Bernardini G, Micheli V, Tozzi MG. Inborn Errors of Purine Salvage and Catabolism. Metabolites 2023; 13:787. [PMID: 37512494 PMCID: PMC10383617 DOI: 10.3390/metabo13070787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/20/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
Cellular purine nucleotides derive mainly from de novo synthesis or nucleic acid turnover and, only marginally, from dietary intake. They are subjected to catabolism, eventually forming uric acid in humans, while bases and nucleosides may be converted back to nucleotides through the salvage pathways. Inborn errors of the purine salvage pathway and catabolism have been described by several researchers and are usually referred to as rare diseases. Since purine compounds play a fundamental role, it is not surprising that their dysmetabolism is accompanied by devastating symptoms. Nevertheless, some of these manifestations are unexpected and, so far, have no explanation or therapy. Herein, we describe several known inborn errors of purine metabolism, highlighting their unexplained pathological aspects. Our intent is to offer new points of view on this topic and suggest diagnostic tools that may possibly indicate to clinicians that the inborn errors of purine metabolism may not be very rare diseases after all.
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Affiliation(s)
- Marcella Camici
- Unità di Biochimica, Dipartimento di Biologia, Università di Pisa, Via San Zeno 51, 56127 Pisa, Italy
| | - Mercedes Garcia-Gil
- Unità di Fisiologia Generale, Dipartimento di Biologia, Università di Pisa, Via San Zeno 31, 56127 Pisa, Italy
- CISUP, Centro per l'Integrazione Della Strumentazione Dell'Università di Pisa, 56127 Pisa, Italy
- Centro di Ricerca Interdipartimentale Nutrafood "Nutraceuticals and Food for Health", Università di Pisa, 56126 Pisa, Italy
| | - Simone Allegrini
- Unità di Biochimica, Dipartimento di Biologia, Università di Pisa, Via San Zeno 51, 56127 Pisa, Italy
- CISUP, Centro per l'Integrazione Della Strumentazione Dell'Università di Pisa, 56127 Pisa, Italy
- Centro di Ricerca Interdipartimentale Nutrafood "Nutraceuticals and Food for Health", Università di Pisa, 56126 Pisa, Italy
| | - Rossana Pesi
- Unità di Biochimica, Dipartimento di Biologia, Università di Pisa, Via San Zeno 51, 56127 Pisa, Italy
| | - Giulia Bernardini
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Vanna Micheli
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, Via A. Moro 2, 53100 Siena, Italy
- LND Famiglie Italiane ODV-Via Giovanetti 15-20, 16149 Genova, Italy
| | - Maria Grazia Tozzi
- Unità di Biochimica, Dipartimento di Biologia, Università di Pisa, Via San Zeno 51, 56127 Pisa, Italy
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Zou J, Zhang G, Li H, Zhao Z, Zhang Q, Pyykkö I, Mäkitie A. Multiple genetic variants involved in both autoimmunity and autoinflammation detected in Chinese patients with sporadic Meniere's disease: a preliminary study. Front Neurol 2023; 14:1159658. [PMID: 37273692 PMCID: PMC10232973 DOI: 10.3389/fneur.2023.1159658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 04/20/2023] [Indexed: 06/06/2023] Open
Abstract
Background The mechanisms of Meniere's disease (MD) remain largely unknown. The purpose of this study was to identify possible genetic variants associated with immune regulation in MD. Methods The whole immune genome of 16 Chinese patients diagnosed with sporadic MD was sequenced using next-generation sequencing. Results Definite pathological variants of MEFV (c.1223G>A, c.1105C>T), COL7A1 (c.5287C>T), and ADA (c.445C>T) contributing to the clinical phenotype were found in three patients. Limited and likely pathological variants of TLR3 (c.2228G>A) and RAB27A (c.560G>A) were detected in one patient each. The following definite pathological variants impairing the structure and function of translated proteins were detected in 10 patients, and multigene variants occurred in five patients: PRF1 (c.710C>A), UNC13D (c.1228A>C), COLEC11 (c.169C>T), RAG2 (c.200G>C), BLM (c.1937G>T), RNF31 (c.2533G>A), FAT4 (c.11498A>G), PEPD (c.788A>G), TNFSF12 (c.470G>A), VPS13B (c.11972A>T), TNFRSF13B (c.226G>A), ERCC6L2 (c.4613A>G), TLR3 (c.2228G>A), ADA (c.445C>T), PEPD (c.151G>A), and MOGS (c.2470G>A). The following limited pathological variants impairing the structure and function of translated proteins were detected in five patients, with double gene variants identified in one patient: EXTL3 (c.1396G>A), MTHFD1 (c.2057G>A), FANCA (c.2039T>C), LPIN2 (c.1814C>T), NBAS (c.4049T>C), and FCN3 (c.734G>A). Conclusion Patients with sporadic MD carry multiple genetic variants involved in multiple steps of immune regulation, which might render patients susceptible to developing inflammation via both autoimmune and autoinflammation mechanisms upon internal stress.
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Affiliation(s)
- Jing Zou
- Department of Otolaryngology-Head and Neck Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
- Research Program in Systems Oncology, Department of Otorhinolaryngology-Head and Neck Surgery, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | - Guoping Zhang
- Department of Otolaryngology-Head and Neck Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Hongbin Li
- Department of Otolaryngology-Head and Neck Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Zikai Zhao
- Department of Otolaryngology-Head and Neck Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Qing Zhang
- Department of Otolaryngology-Head and Neck Surgery, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Ilmari Pyykkö
- Hearing and Balance Research Unit, Field of Otolaryngology, School of Medicine, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Antti Mäkitie
- Research Program in Systems Oncology, Department of Otorhinolaryngology-Head and Neck Surgery, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
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Vlajkovic SM, Thorne PR. Purinergic Signalling in the Cochlea. Int J Mol Sci 2022; 23:ijms232314874. [PMID: 36499200 PMCID: PMC9741428 DOI: 10.3390/ijms232314874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/24/2022] [Accepted: 11/25/2022] [Indexed: 11/29/2022] Open
Abstract
The mammalian cochlea is the sensory organ of hearing with a delicate, highly organised structure that supports unique operating mechanisms. ATP release from the secretory tissues of the cochlear lateral wall (stria vascularis) triggers numerous physiological responses by activating P2 receptors in sensory, supporting and neural tissues. Two families of P2 receptors, ATP-gated ion channels (P2X receptors) and G protein-coupled P2Y receptors, activate intracellular signalling pathways that regulate cochlear development, homeostasis, sensory transduction, auditory neurotransmission and response to stress. Of particular interest is a purinergic hearing adaptation, which reflects the critical role of the P2X2 receptor in adaptive cochlear response to elevated sound levels. Other P2 receptors are involved in the maturation of neural processes and frequency selectivity refinement in the developing cochlea. Extracellular ATP signalling is regulated by a family of surface-located enzymes collectively known as "ectonucleotidases" that hydrolyse ATP to adenosine. Adenosine is a constitutive cell metabolite with an established role in tissue protection and regeneration. The differential activation of A1 and A2A adenosine receptors defines the cochlear response to injury caused by oxidative stress, inflammation, and activation of apoptotic pathways. A1 receptor agonism, A2A receptor antagonism, and increasing adenosine levels in cochlear fluids all represent promising therapeutic tools for cochlear rescue from injury and prevention of hearing loss.
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Affiliation(s)
- Srdjan M. Vlajkovic
- Department of Physiology and The Eisdell Moore Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Correspondence: ; Tel.: +64-9-9239782
| | - Peter R. Thorne
- Department of Physiology and The Eisdell Moore Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- Section of Audiology, School of Population Health, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
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Zou J, Zhao Z, Zhang G, Zhang Q, Pyykkö I. MEFV, IRF8, ADA, PEPD, and NBAS gene variants and elevated serum cytokines in a patient with unilateral sporadic Meniere’s disease and vascular congestion over the endolymphatic sac. J Otol 2022; 17:175-181. [PMID: 35847575 PMCID: PMC9270563 DOI: 10.1016/j.joto.2022.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/05/2022] [Accepted: 03/09/2022] [Indexed: 10/25/2022] Open
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Tsui M, Min W, Ng S, Dobbs K, Notarangelo LD, Dror Y, Grunebaum E. The Use of Induced Pluripotent Stem Cells to Study the Effects of Adenosine Deaminase Deficiency on Human Neutrophil Development. Front Immunol 2021; 12:748519. [PMID: 34777360 PMCID: PMC8582638 DOI: 10.3389/fimmu.2021.748519] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/30/2021] [Indexed: 11/13/2022] Open
Abstract
Inherited defects that abrogate the function of the adenosine deaminase (ADA) enzyme and consequently lead to the accumulation of toxic purine metabolites cause profound lymphopenia and severe combined immune deficiency. Additionally, neutropenia and impaired neutrophil function have been reported among ADA-deficient patients. However, due to the rarity of the disorder, the neutrophil developmental abnormalities and the mechanisms contributing to them have not been characterized. Induced pluripotent stem cells (iPSC) generated from two unrelated ADA-deficient patients and from healthy controls were differentiated through embryoid bodies into neutrophils. ADA deficiency led to a significant reduction in the number of all early multipotent hematopoietic progenitors. At later stages of differentiation, ADA deficiency impeded the formation of granulocyte colonies in methylcellulose cultures, leading to a significant decrease in the number of neutrophils generated from ADA-deficient iPSCs. The viability and apoptosis of ADA-deficient neutrophils isolated from methylcellulose cultures were unaffected, suggesting that the abnormal purine homeostasis in this condition interferes with differentiation or proliferation. Additionally, there was a significant increase in the percentage of hyperlobular ADA-deficient neutrophils, and these neutrophils demonstrated significantly reduced ability to phagocytize fluorescent microspheres. Supplementing iPSCs and methylcellulose cultures with exogenous ADA, which can correct adenosine metabolism, reversed all abnormalities, cementing the critical role of ADA in neutrophil development. Moreover, chemical inhibition of the ribonucleotide reductase (RNR) enzyme, using hydroxyurea or a combination of nicotinamide and trichostatin A in iPSCs from healthy controls, led to abnormal neutrophil differentiation similar to that observed in ADA deficiency, implicating RNR inhibition as a potential mechanism for the neutrophil abnormalities. In conclusion, the findings presented here demonstrate the important role of ADA in the development and function of neutrophils while clarifying the mechanisms responsible for the neutrophil abnormalities in ADA-deficient patients.
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Affiliation(s)
- Michael Tsui
- Developmental and Stem Cell Biology Program, Hospital for Sick Children, Toronto, ON, Canada.,The Institute of Medical Sciences, The University of Toronto, Toronto, ON, Canada
| | - Weixian Min
- Developmental and Stem Cell Biology Program, Hospital for Sick Children, Toronto, ON, Canada
| | - Stephanie Ng
- The Institute of Medical Sciences, The University of Toronto, Toronto, ON, Canada.,Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - Kerry Dobbs
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Luigi D Notarangelo
- Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Yigal Dror
- The Institute of Medical Sciences, The University of Toronto, Toronto, ON, Canada.,Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, ON, Canada.,Marrow Failure and Myelodysplasia Program, Division of Hematology/Oncology, Department of Pediatrics, The Hospital for Sick Children, Toronto, ON, Canada
| | - Eyal Grunebaum
- Developmental and Stem Cell Biology Program, Hospital for Sick Children, Toronto, ON, Canada.,The Institute of Medical Sciences, The University of Toronto, Toronto, ON, Canada.,Division of Immunology and Allergy, Department of Pediatrics, The Hospital for Sick Children, Toronto, ON, Canada
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Hearing characteristics of infantile-onset Pompe disease after early enzyme-replacement therapy. Orphanet J Rare Dis 2021; 16:348. [PMID: 34353347 PMCID: PMC8340467 DOI: 10.1186/s13023-021-01817-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Accepted: 04/06/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Studies suggest that enzyme-replacement therapy (ERT) is crucial to the survival of patients with infantile-onset Pompe disease (IOPD). Hearing impairment (HI) is one of the clinical sequelae observed in long-term survivors. However, the benefits of early ERT for hearing outcomes have not yet been reported. This study aimed to investigate the impact of early ERT on IOPD patients. METHODS This retrospective longitudinal study recruited IOPD patients who were referred by newborn screening for confirmatory diagnosis based on our rapid diagnostic criteria and received early ERT treatment between January 1, 2010, and January 31, 2018. The hearing test battery included a tympanogram, otoacoustic emission, auditory brainstem evoked response (ABR), pure-tone audiometry or conditioned play audiometry. RESULTS Nineteen patients with IOPD were identified, 6 of whom had hearing impairment (HI); 1 had conductive HI, 2 had sensorineural HI (one had bilateral mild HI and one had mild HI in a single ear) and 1 had moderate mixed-type HI. Two patients failed the newborn screening test and had mild HI in the ABR. The mean age of the initial time to ERT was 11.05 ± 4.31 days, and the HI rate was 31.6% (6/19). CONCLUSION Our study is the largest cohort to show the characteristic hearing outcomes of IOPD patients after ERT. Early ERT within 2 weeks after birth may contribute to better hearing outcomes. Clinicians should be vigilant in testing for the hearing issues associated with IOPD and should intervene early if any HI is detected.
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Garcia-Gil M, Camici M, Allegrini S, Pesi R, Tozzi MG. Metabolic Aspects of Adenosine Functions in the Brain. Front Pharmacol 2021; 12:672182. [PMID: 34054547 PMCID: PMC8160517 DOI: 10.3389/fphar.2021.672182] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 04/27/2021] [Indexed: 12/13/2022] Open
Abstract
Adenosine, acting both through G-protein coupled adenosine receptors and intracellularly, plays a complex role in multiple physiological and pathophysiological processes by modulating neuronal plasticity, astrocytic activity, learning and memory, motor function, feeding, control of sleep and aging. Adenosine is involved in stroke, epilepsy and neurodegenerative pathologies. Extracellular concentration of adenosine in the brain is tightly regulated. Adenosine may be generated intracellularly in the central nervous system from degradation of AMP or from the hydrolysis of S-adenosyl homocysteine, and then exit via bi-directional nucleoside transporters, or extracellularly by the metabolism of released nucleotides. Inactivation of extracellular adenosine occurs by transport into neurons or neighboring cells, followed by either phosphorylation to AMP by adenosine kinase or deamination to inosine by adenosine deaminase. Modulation of the nucleoside transporters or of the enzymatic activities involved in the metabolism of adenosine, by affecting the levels of this nucleoside and the activity of adenosine receptors, could have a role in the onset or the development of central nervous system disorders, and can also be target of drugs for their treatment. In this review, we focus on the contribution of 5'-nucleotidases, adenosine kinase, adenosine deaminase, AMP deaminase, AMP-activated protein kinase and nucleoside transporters in epilepsy, cognition, and neurodegenerative diseases with a particular attention on amyotrophic lateral sclerosis and Huntington's disease. We include several examples of the involvement of components of the adenosine metabolism in learning and of the possible use of modulators of enzymes involved in adenosine metabolism or nucleoside transporters in the amelioration of cognition deficits.
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Affiliation(s)
- Mercedes Garcia-Gil
- Department of Biology, Unit of Physiology, University of Pisa, Pisa, Italy.,Interdepartmental Research Center "Nutraceuticals and Food for Health", University of Pisa, Pisa, Italy
| | - Marcella Camici
- Department of Biology, Unit of Biochemistry, University of Pisa, Pisa, Italy
| | - Simone Allegrini
- Department of Biology, Unit of Biochemistry, University of Pisa, Pisa, Italy
| | - Rossana Pesi
- Department of Biology, Unit of Biochemistry, University of Pisa, Pisa, Italy
| | - Maria Grazia Tozzi
- Department of Biology, Unit of Biochemistry, University of Pisa, Pisa, Italy
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Siu JM, Negandhi J, Harrison RV, Wolter NE, James A. Ultrasonic bone removal from the ossicular chain affects cochlear structure and function. J Otolaryngol Head Neck Surg 2021; 50:23. [PMID: 33810814 PMCID: PMC8017701 DOI: 10.1186/s40463-021-00491-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 01/11/2021] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Ultrasonic bone removal devices (UBD) are capable of cutting through bony tissue without injury to adjacent soft tissue. The feasibility and safety of using this technology for removal of bone from an intact ossicular chain (as might be required for otosclerosis or congenital fixation) was investigated in an animal model. METHODS This was a prospective animal study conducted on seven anesthetised adult chinchillas. An UBD was used to remove bone from the malleus head in situ. Pre and post-operative distortion product otoacoustic emission (DPOAE) levels and auditory brainstem response (ABR) thresholds were recorded. Scanning electron microscopy (SEM) was used to assess cochlear haircell integrity. RESULTS Precise removal of a small quantity of bone from the malleus head was achieved by a 30s application of UBD without disruption of the ossicular chain or tympanic membrane. DPOAEs became undetectable after the intervention with signal-to-noise ratios (SNR) < 5 dB SPL in all ears. Furthermore, ABR thresholds were elevated > 85 dB SPL in 13 ears. SEM showed significant disruption of structural integrity of the organ of Corti, specifically loss and damage of outer haircells. CONCLUSIONS Although UBD can be used to reshape an ossicle without middle ear injury, prolonged contact with the ossicular chain can cause structural and functional injury to the cochlea. Extensive cochlea pathology was found, but we did not investigate for recovery from any temporary threshold shift. In the authors' opinion, further study should be undertaken before consideration is given to use of the device for release of ossicular fixation.
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Affiliation(s)
- Jennifer M Siu
- Department of Otolaryngology - Head & Neck Surgery, University of Toronto, Toronto, Canada
| | - Jaina Negandhi
- Program in Neuroscience and Mental Health, Hospital for Sick Children, Toronto, Canada
| | - Robert V Harrison
- Department of Otolaryngology - Head & Neck Surgery, University of Toronto, Toronto, Canada
- Program in Neuroscience and Mental Health, Hospital for Sick Children, Toronto, Canada
- Department of Otolaryngology, Hospital for Sick Children, University of Toronto, 555 University Avenue, Room 6133, Burton Wing, Toronto, ON, M5G 1X8, Canada
| | - Nikolaus E Wolter
- Department of Otolaryngology - Head & Neck Surgery, University of Toronto, Toronto, Canada
- Department of Otolaryngology, Hospital for Sick Children, University of Toronto, 555 University Avenue, Room 6133, Burton Wing, Toronto, ON, M5G 1X8, Canada
| | - Adrian James
- Department of Otolaryngology - Head & Neck Surgery, University of Toronto, Toronto, Canada.
- Department of Otolaryngology, Hospital for Sick Children, University of Toronto, 555 University Avenue, Room 6133, Burton Wing, Toronto, ON, M5G 1X8, Canada.
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Manalo JM, Liu H, Ding D, Hicks J, Sun H, Salvi R, Kellems RE, Pereira FA, Xia Y. Adenosine A2B receptor: A pathogenic factor and a therapeutic target for sensorineural hearing loss. FASEB J 2020; 34:15771-15787. [PMID: 33131093 DOI: 10.1096/fj.202000939r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/04/2020] [Accepted: 08/24/2020] [Indexed: 12/14/2022]
Abstract
Over 466 million people worldwide are diagnosed with hearing loss (HL). About 90% of HL cases are sensorineural HL (SNHL) with treatments limited to hearing aids and cochlear implants with no FDA-approved drugs. Intriguingly, ADA-deficient patients have been reported to have bilateral SNHL, however, its underlying cellular and molecular basis remain unknown. We report that Ada-/- mice, phenocopying ADA-deficient humans, displayed SNHL. Ada-/- mice cochlea with elevated adenosine caused substantial nerve fiber demyelination and mild hair cell loss. ADA enzyme therapy in these mice normalized cochlear adenosine levels, attenuated SNHL, and prevented demyelination. Additionally, ADA enzyme therapy rescued SNHL by restoring nerve fiber structure in Ada-/- mice post two-week drug withdrawal. Moreover, elevated cochlear adenosine in untreated mice was associated with enhanced Adora2b gene expression. Preclinically, ADORA2B-specific antagonist treatment in Ada-/- mice significantly improved HL, nerve fiber density, and myelin compaction. We also provided genetic evidence that ADORA2B is detrimental for age-related SNHL by impairing cochlear myelination in WT aged mice. Overall, understanding purinergic molecular signaling in SNHL in Ada-/- mice allows us to further discover that ADORA2B is also a pathogenic factor underlying aged-related SNHL by impairing cochlear myelination and lowering cochlear adenosine levels or blocking ADORA2B signaling are effective therapies for SNHL.
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Affiliation(s)
- Jeanne M Manalo
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, USA.,Graduate School of Biomedical Science, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Hong Liu
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, USA.,Graduate School of Biomedical Science, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Dalian Ding
- Department of Communicative Disorders and Sciences, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - John Hicks
- Department of Pathology, Texas Children's Hospital, Houston, TX, USA
| | - Hong Sun
- Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, China
| | - Richard Salvi
- Department of Communicative Disorders and Sciences, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - Rodney E Kellems
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, USA.,Graduate School of Biomedical Science, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Fred A Pereira
- Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
| | - Yang Xia
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, USA.,Graduate School of Biomedical Science, University of Texas Health Science Center at Houston, Houston, TX, USA
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Murguia-Favela L, Min W, Loves R, Leon-Ponte M, Grunebaum E. Comparison of elapegademase and pegademase in ADA-deficient patients and mice. Clin Exp Immunol 2020; 200:176-184. [PMID: 31989577 DOI: 10.1111/cei.13420] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2020] [Indexed: 01/08/2023] Open
Abstract
The absence of adenosine deaminase (ADA) causes severe combined immune deficiency (SCID), which has been treated with PEGylated bovine-extracted ADA (ADAGEN). ADAGEN was recently replaced by a PEGylated recombinant bovine ADA, expressed in Escherichia coli (elapegademase, ELA-ADA). Limited information on ELA-ADA is available. ADA enzymatic activity of ELA-ADA and ADAGEN was assessed in vitro at diverse dilutions. ADA activity and immune reconstitution in an ADA-SCID patient treated with ELA-ADA were compared with age-matched patients previously treated with ADAGEN. ADA activity and thymus reconstitution were evaluated in ADA-deficient mice following ELA-ADA or ADAGEN administered from 7 days postpartum. In vitro, ADA activity of ELA-ADA and ADAGEN were similar at all dilutions. In an ADA-SCID patient, ELA-ADA treatment led to a marked increase in trough plasma ADA activity, which was 20% higher than in a patient previously treated with ADAGEN. A marked increase in T cell numbers and generation of naive T cells was evident following 3 months of ELA-ADA treatment, while T cell numbers increased following 4 months in 3 patients previously treated with ADAGEN. T cell proliferations stimulation normalized and thymus shadow became evident following ELA-ADA treatment. ADA activity was significantly increased in the blood of ADA-deficient mice following ELA-ADA compared to ADAGEN, while both treatments improved the mice weights, the weight, number of cells in their thymus and thymocyte subpopulations. ELA-ADA has similar in- vitro and possibly better in-vivo activity than ADAGEN. Future studies will determine whether ELA-ADA results in improved long-term immune reconstitution.
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Affiliation(s)
- L Murguia-Favela
- Section of Hematology and Immunology, Department of Pediatrics, Alberta Children's Hospital and University of Calgary, Calgary, Canada
| | - W Min
- Developmental and Stem Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - R Loves
- Developmental and Stem Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - M Leon-Ponte
- Developmental and Stem Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - E Grunebaum
- Developmental and Stem Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, Canada.,Division of Immunology and Allergy, Department of Pediatrics, Hospital for Sick Children, Toronto, Canada
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