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Hoogstraten CA, Schirris TJJ, Russel FGM. Unlocking mitochondrial drug targets: The importance of mitochondrial transport proteins. Acta Physiol (Oxf) 2024; 240:e14150. [PMID: 38666512 DOI: 10.1111/apha.14150] [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: 10/04/2023] [Revised: 03/02/2024] [Accepted: 04/12/2024] [Indexed: 05/12/2024]
Abstract
A disturbed mitochondrial function contributes to the pathology of many common diseases. These organelles are therefore important therapeutic targets. On the contrary, many adverse effects of drugs can be explained by a mitochondrial off-target effect, in particular, due to an interaction with carrier proteins in the inner membrane. Yet this class of transport proteins remains underappreciated and understudied. The aim of this review is to provide a deeper understanding of the role of mitochondrial carriers in health and disease and their significance as drug targets. We present literature-based evidence that mitochondrial carrier proteins are associated with prevalent diseases and emphasize their potential as drug (off-)target sites by summarizing known mitochondrial drug-transporter interactions. Studying these carriers will enhance our knowledge of mitochondrial drug on- and off-targets and provide opportunities to further improve the efficacy and safety of drugs.
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Affiliation(s)
- Charlotte A Hoogstraten
- Department of Pharmacy, Division of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands
- Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Tom J J Schirris
- Department of Pharmacy, Division of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands
- Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Frans G M Russel
- Department of Pharmacy, Division of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands
- Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
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2
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Aslamkhan AG, Michna L, Podtelezhnikov A, Vlasakova K, Suemizu H, Ohnishi Y, Liu L, Lane P, Xu Q, Kuhls MC, Wang Z, Pacchione S, Erdos Z, Tracy RW, Koeplinger K, Muniappa N, Valentine J, Galijatovic-Idrizbegovic A, Glaab WE, Sistare FD, Lebron J. A mechanistic biomarker investigation of fialuridine hepatotoxicity using the chimeric TK-NOG Hu-liver mouse model and in vitro micropatterned hepatocyte cocultures. Toxicol Res (Camb) 2024; 13:tfad120. [PMID: 38223529 PMCID: PMC10784659 DOI: 10.1093/toxres/tfad120] [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: 05/31/2023] [Revised: 10/20/2023] [Accepted: 12/01/2023] [Indexed: 01/16/2024] Open
Abstract
Fialuridine (FIAU) is a nucleoside-based drug that caused liver failure and deaths in a human clinical trial that were not predicted by nonclinical safety studies. A recent report concluded that a TK-NOG humanized liver (hu-liver) mouse model detected human-specific FIAU liver toxicity, and broader use of that model could improve drug safety testing. We further evaluated this model at similar dose levels to assess FIAU sensitivity and potential mechanistic biomarkers. Although we were unable to reproduce the marked acute liver toxicity with two separate studies (including one with a "sensitized" donor), we identified molecular biomarkers reflecting the early stages of FIAU mitochondrial toxicity, which were not seen with its stereoisomer (FIRU). Dose dependent FIAU-induced changes in hu-liver mice included more pronounced reductions in mitochondrial to nuclear DNA (mtDNA/nucDNA) ratios in human hepatocytes compared to mouse hepatocytes and kidneys of the same animals. FIAU treatment also triggered a p53 transcriptional response and opposing changes in transcripts of nuclear- and mitochondrial-encoded mitochondrial proteins. The time dependent accumulation of FIAU into mtDNA is consistent with the ≥9-week latency of liver toxicity observed for FIAU in the clinic. Similar changes were observed in an in vitro micro-patterned hepatocyte coculture system. In addition, FIAU-dependent mtDNA/nucDNA ratio and transcriptional alterations, especially reductions in mitochondrially encoded transcripts, were seen in livers of non-engrafted TK-NOG and CD-1 mice dosed for a shorter period. Conclusion: These mechanistic biomarker findings can be leveraged in an in vitro model and in a more routine preclinical model (CD-1 mice) to identify nucleosides with such a FIAU-like mitochondrial toxicity mechanistic liability potential. Further optimization of the TK-NOG hu-liver mouse model is necessary before broader adoption for drug safety testing.
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Affiliation(s)
- Amy G Aslamkhan
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Laura Michna
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Alexei Podtelezhnikov
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Katerina Vlasakova
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Hiroshi Suemizu
- Laboratory Animal Research, Central Institute for Experimental Animals, 210-0821 Kawasaki-ku, Kawasaki 3-25-12 Tonomachi, Japan
| | - Yasuyuki Ohnishi
- Laboratory Animal Research, Central Institute for Experimental Animals, 210-0821 Kawasaki-ku, Kawasaki 3-25-12 Tonomachi, Japan
| | - Liping Liu
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Pamela Lane
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Qiuwei Xu
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Matthew C Kuhls
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Zhibin Wang
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Stephen Pacchione
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Zoltan Erdos
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Rodger William Tracy
- Pharmacokinetics, Dynamics, Metabolism and Bioanalytics, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA, United States
| | - Kenneth Koeplinger
- Pharmacokinetics, Dynamics, Metabolism and Bioanalytics, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA, United States
| | - Nagaraja Muniappa
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - John Valentine
- Pharmacokinetics, Dynamics, Metabolism and Bioanalytics, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA, United States
| | | | - Warren E Glaab
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Frank D Sistare
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
| | - Jose Lebron
- Nonclinical Drug Safety, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA 19486, United States
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3
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Hau RK, Wright SH, Cherrington NJ. Addressing the Clinical Importance of Equilibrative Nucleoside Transporters in Drug Discovery and Development. Clin Pharmacol Ther 2023; 114:780-794. [PMID: 37404197 PMCID: PMC11347013 DOI: 10.1002/cpt.2984] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 05/30/2023] [Indexed: 07/06/2023]
Abstract
The US Food and Drug Administration (FDA), European Medicines Agency (EMA), and Pharmaceuticals and Medical Devices Agency (PMDA) guidances on small-molecule drug-drug interactions (DDIs), with input from the International Transporter Consortium (ITC), recommend the evaluation of nine drug transporters. Although other clinically relevant drug uptake and efflux transporters have been discussed in ITC white papers, they have been excluded from further recommendation by the ITC and are not included in current regulatory guidances. These include the ubiquitously expressed equilibrative nucleoside transporters (ENT) 1 and ENT2, which have been recognized by the ITC for their potential role in clinically relevant nucleoside analog drug interactions for patients with cancer. Although there is comparatively limited clinical evidence supporting their role in DDI risk or other adverse drug reactions (ADRs) compared with the nine highlighted transporters, several in vitro and in vivo studies have identified ENT interactions with non-nucleoside/non-nucleotide drugs, in addition to nucleoside/nucleotide analogs. Some noteworthy examples of compounds that interact with ENTs include cannabidiol and selected protein kinase inhibitors, as well as the nucleoside analogs remdesivir, EIDD-1931, gemcitabine, and fialuridine. Consequently, DDIs involving the ENTs may be responsible for therapeutic inefficacy or off-target toxicity. Evidence suggests that ENT1 and ENT2 should be considered as transporters potentially involved in clinically relevant DDIs and ADRs, thereby warranting further investigation and regulatory consideration.
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Affiliation(s)
- Raymond K Hau
- Department of Pharmacology & Toxicology, College of Pharmacy, The University of Arizona, Tucson, Arizona, USA
| | - Stephen H Wright
- Department of Physiology, College of Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Nathan J Cherrington
- Department of Pharmacology & Toxicology, College of Pharmacy, The University of Arizona, Tucson, Arizona, USA
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4
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Wu X, Jiang D, Yang Y, Li S, Ding Q. Modeling drug-induced liver injury and screening for anti-hepatofibrotic compounds using human PSC-derived organoids. CELL REGENERATION (LONDON, ENGLAND) 2023; 12:6. [PMID: 36864321 PMCID: PMC9981852 DOI: 10.1186/s13619-022-00148-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 11/01/2022] [Indexed: 03/04/2023]
Abstract
Preclinical models that can accurately predict the toxicity and efficacy of candidate drugs to human liver tissue are in urgent need. Human liver organoid (HLO) derived from human pluripotent stem cells offers a possible solution. Herein, we generated HLOs, and demonstrated the utility of these HLOs in modeling a diversity of phenotypes associated with drug-induced liver injury (DILI), including steatosis, fibrosis, and immune responses. Phenotypic changes in HLOs after treatment with tool compounds such as acetaminophen, fialuridine, methotrexate, or TAK-875 showed high concordance with human clinical data in drug safety testings. Moreover, HLOs were able to model liver fibrogenesis induced by TGFβ or LPS treatment. We further devised a high-content analysis system, and established a high-throughput anti-fibrosis drug screening system using HLOs. SD208 and Imatinib were identified that can significantly suppress fibrogenesis induced by TGFβ, LPS, or methotrexate. Taken together, our studies demonstrated the potential applications of HLOs in drug safety testing and anti-fibrotic drug screening.
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Affiliation(s)
- Xiaoshan Wu
- grid.28056.390000 0001 2163 4895School of Biotechnology, East China University of Science and Technology, Shanghai, 200237 P. R. China ,grid.410726.60000 0004 1797 8419CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031 P. R. China ,School of Pharmacy, Fujian Health College, Fujian, 350101 P. R. China
| | - Dacheng Jiang
- grid.410726.60000 0004 1797 8419CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031 P. R. China
| | - Yi Yang
- grid.28056.390000 0001 2163 4895School of Biotechnology, East China University of Science and Technology, Shanghai, 200237 P. R. China
| | - Shuang Li
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, P. R. China.
| | - Qiurong Ding
- School of Biotechnology, East China University of Science and Technology, Shanghai, 200237, P. R. China. .,CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, P. R. China. .,Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China. .,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, P. R. China.
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5
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Özvegy-Laczka C, Ungvári O, Bakos É. Fluorescence-based methods for studying activity and drug-drug interactions of hepatic solute carrier and ATP binding cassette proteins involved in ADME-Tox. Biochem Pharmacol 2023; 209:115448. [PMID: 36758706 DOI: 10.1016/j.bcp.2023.115448] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/11/2023]
Abstract
In humans, approximately 70% of drugs are eliminated through the liver. This process is governed by the concerted action of membrane transporters and metabolic enzymes. Transporters mediating hepatocellular uptake of drugs belong to the SLC (Solute carrier) superfamily of transporters. Drug efflux either toward the portal vein or into the bile is mainly mediated by active transporters of the ABC (ATP Binding Cassette) family. Alteration in the function and/or expression of liver transporters due to mutations, disease conditions, or co-administration of drugs or food components can result in altered pharmacokinetics. On the other hand, drugs or food components interacting with liver transporters may also interfere with liver function (e.g., bile acid homeostasis) and may even cause liver toxicity. Accordingly, certain transporters of the liver should be investigated already at an early stage of drug development. Most frequently radioactive probes are applied in these drug-transporter interaction tests. However, fluorescent probes are cost-effective and sensitive alternatives to radioligands, and are gaining wider application in drug-transporter interaction tests. In our review, we summarize our current understanding about hepatocyte ABC and SLC transporters affected by drug interactions. We provide an update of the available fluorescent and fluorogenic/activable probes applicable in in vitro or in vivo testing of these ABC and SLC transporters, including near-infrared transporter probes especially suitable for in vivo imaging. Furthermore, our review gives a comprehensive overview of the available fluorescence-based methods, not directly relying on the transport of the probe, suitable for the investigation of hepatic ABC or SLC-type drug transporters.
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Affiliation(s)
- Csilla Özvegy-Laczka
- Institute of Enzymology, RCNS, Eötvös Loránd Research Network, H-1117 Budapest, Magyar tudósok krt. 2., Hungary.
| | - Orsolya Ungvári
- Institute of Enzymology, RCNS, Eötvös Loránd Research Network, H-1117 Budapest, Magyar tudósok krt. 2., Hungary; Doctoral School of Biology, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Éva Bakos
- Institute of Enzymology, RCNS, Eötvös Loránd Research Network, H-1117 Budapest, Magyar tudósok krt. 2., Hungary
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6
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Bhardwaj G, Kaur R, Kaur N, Singh N. Gold nanoparticles capped DHPMs for meliorate detection of antiretroviral drug: Azidothymidine. Talanta 2022; 249:123591. [DOI: 10.1016/j.talanta.2022.123591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 12/10/2021] [Accepted: 05/25/2022] [Indexed: 11/17/2022]
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7
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Wang AQ, Hagen NR, Padilha EC, Yang M, Shah P, Chen CZ, Huang W, Terse P, Sanderson P, Zheng W, Xu X. Preclinical Pharmacokinetics and In Vitro Properties of GS-441524, a Potential Oral Drug Candidate for COVID-19 Treatment. Front Pharmacol 2022; 13:918083. [PMID: 36052127 PMCID: PMC9424906 DOI: 10.3389/fphar.2022.918083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 06/15/2022] [Indexed: 01/02/2023] Open
Abstract
Preclinical pharmacokinetics (PK) and In Vitro ADME properties of GS-441524, a potential oral agent for the treatment of Covid-19, were studied. GS-441524 was stable in vitro in liver microsomes, cytosols, and hepatocytes of mice, rats, monkeys, dogs, and humans. The plasma free fractions of GS-441524 were 62-78% across all studied species. The in vitro transporter study results showed that GS-441524 was a substrate of MDR1, BCRP, CNT3, ENT1, and ENT2; but not a substrate of CNT1, CNT2, and ENT4. GS-441524 had a low to moderate plasma clearance (CLp), ranging from 4.1 mL/min/kg in dogs to 26 mL/min/kg in mice; the steady state volume distribution (Vdss) ranged from 0.9 L/kg in dogs to 2.4 L/kg in mice after IV administration. Urinary excretion appeared to be the major elimination process for GS-441524. Following oral administration, the oral bioavailability was 8.3% in monkeys, 33% in rats, 39% in mice, and 85% in dogs. The PK and ADME properties of GS-441524 support its further development as an oral drug candidate.
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Affiliation(s)
- Amy Q. Wang
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, United States
| | | | | | | | | | | | | | | | | | | | - Xin Xu
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, United States
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8
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Huttunen KM, Terasaki T, Urtti A, Montaser AB, Uchida Y. Pharmacoproteomics of Brain Barrier Transporters and Substrate Design for the Brain Targeted Drug Delivery. Pharm Res 2022; 39:1363-1392. [PMID: 35257288 PMCID: PMC9246989 DOI: 10.1007/s11095-022-03193-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/08/2022] [Indexed: 12/12/2022]
Abstract
One of the major reasons why central nervous system (CNS)-drug development has been challenging in the past, is the barriers that prevent substances entering from the blood circulation into the brain. These barriers include the blood-brain barrier (BBB), blood-spinal cord barrier (BSCB), blood-cerebrospinal fluid barrier (BCSFB), and blood-arachnoid barrier (BAB), and they differ from each other in their transporter protein expression and function as well as among the species. The quantitative expression profiles of the transporters in the CNS-barriers have been recently revealed, and in this review, it is described how they affect the pharmacokinetics of compounds and how these expression differences can be taken into account in the prediction of brain drug disposition in humans, an approach called pharmacoproteomics. In recent years, also structural biology and computational resources have progressed remarkably, enabling a detailed understanding of the dynamic processes of transporters. Molecular dynamics simulations (MDS) are currently used commonly to reveal the conformational changes of the transporters and to find the interactions between the substrates and the protein during the binding, translocation in the transporter cavity, and release of the substrate on the other side of the membrane. The computational advancements have also aided in the rational design of transporter-utilizing compounds, including prodrugs that can be actively transported without losing potency towards the pharmacological target. In this review, the state-of-art of these approaches will be also discussed to give insights into the transporter-mediated drug delivery to the CNS.
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Affiliation(s)
- Kristiina M Huttunen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland.
| | - Tetsuya Terasaki
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland.
| | - Arto Urtti
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Ahmed B Montaser
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Yasuo Uchida
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba-ku, Sendai, 980-8578, Japan
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9
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Gilmore JC, Zhang G, Cameron DW, Serghides L, Bendayan R. Impact of in-utero antiretroviral drug exposure on expression of membrane-associated transporters in mouse placenta and fetal brain. AIDS 2021; 35:2249-2258. [PMID: 34175869 DOI: 10.1097/qad.0000000000003009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Although antiretroviral therapy (ART) during pregnancy is effective in limiting vertical HIV transmission, adverse outcomes persist amongst uninfected children exposed to antiretroviral drugs in utero. Membrane-associated drug transporters, metabolic enzymes, and tight junction proteins play important roles in adult antiretroviral drug disposition and toxicity; however, the fetal expression of these proteins in the context of ART, and their impact on in-utero antiretroviral drug distribution remain poorly understood. This study aimed to characterize the role of these proteins in modulating in-utero antiretroviral drug exposure. METHODS Pregnant mice were exposed to an ART regimen consisting of lamivudine, abacavir, atazanavir, and ritonavir, at clinically relevant doses. Fetal brain, liver, placenta amniotic fluid, and maternal plasma were collected on gestational day 18.5 and concentration of antiretroviral drugs in fetal tissues was measured by LC/MS/MS, whereas transporter expression was assessed by qPCR. RESULTS Abacavir and lamivudine were detected in fetal brain and amniotic fluid, whereas atazanavir and ritonavir were detected in amniotic fluid only. Robust mRNA expression of key transporters was observed in adult and fetal tissues, and sex differences were identified in the expression of Abcc1 and Slc29a1 in the placenta. Antiretroviral drug exposure was associated with a reduction in relative placental Abcg2, Abcc1, and Slc29a1 expression. CONCLUSION These findings identify a novel effect of fetal sex and antiretroviral drug treatment on the expression of placental transporters in a mouse model, and characterize the penetration of lamivudine and abacavir into fetal brain, uncovering a potential role of transporters in modulating fetal exposure to antiretroviral drugs.
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Affiliation(s)
- Julian C Gilmore
- Department of Pharmaceutical Sciences, University of Toronto, Toronto
| | - Guijun Zhang
- Clinical Investigation Unit, University of Ottawa at the Ottawa Hospital/Research Institute, Ottawa
| | - D William Cameron
- Clinical Investigation Unit, University of Ottawa at the Ottawa Hospital/Research Institute, Ottawa
| | - Lena Serghides
- Department of Immunology and Institute of Medical Sciences, University of Toronto
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Reina Bendayan
- Department of Pharmaceutical Sciences, University of Toronto, Toronto
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10
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Emerging roles of dysregulated adenosine homeostasis in brain disorders with a specific focus on neurodegenerative diseases. J Biomed Sci 2021; 28:70. [PMID: 34635103 PMCID: PMC8507231 DOI: 10.1186/s12929-021-00766-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 10/04/2021] [Indexed: 02/07/2023] Open
Abstract
In modern societies, with an increase in the older population, age-related neurodegenerative diseases have progressively become greater socioeconomic burdens. To date, despite the tremendous effort devoted to understanding neurodegenerative diseases in recent decades, treatment to delay disease progression is largely ineffective and is in urgent demand. The development of new strategies targeting these pathological features is a timely topic. It is important to note that most degenerative diseases are associated with the accumulation of specific misfolded proteins, which is facilitated by several common features of neurodegenerative diseases (including poor energy homeostasis and mitochondrial dysfunction). Adenosine is a purine nucleoside and neuromodulator in the brain. It is also an essential component of energy production pathways, cellular metabolism, and gene regulation in brain cells. The levels of intracellular and extracellular adenosine are thus tightly controlled by a handful of proteins (including adenosine metabolic enzymes and transporters) to maintain proper adenosine homeostasis. Notably, disruption of adenosine homeostasis in the brain under various pathophysiological conditions has been documented. In the past two decades, adenosine receptors (particularly A1 and A2A adenosine receptors) have been actively investigated as important drug targets in major degenerative diseases. Unfortunately, except for an A2A antagonist (istradefylline) administered as an adjuvant treatment with levodopa for Parkinson's disease, no effective drug based on adenosine receptors has been developed for neurodegenerative diseases. In this review, we summarize the emerging findings on proteins involved in the control of adenosine homeostasis in the brain and discuss the challenges and future prospects for the development of new therapeutic treatments for neurodegenerative diseases and their associated disorders based on the understanding of adenosine homeostasis.
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Mikdar M, González-Menéndez P, Cai X, Zhang Y, Serra M, Dembele AK, Boschat AC, Sanquer S, Chhuon C, Guerrera IC, Sitbon M, Hermine O, Colin Y, Le Van Kim C, Kinet S, Mohandas N, Xia Y, Peyrard T, Taylor N, Azouzi S. The equilibrative nucleoside transporter ENT1 is critical for nucleotide homeostasis and optimal erythropoiesis. Blood 2021; 137:3548-3562. [PMID: 33690842 PMCID: PMC8225918 DOI: 10.1182/blood.2020007281] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 02/21/2021] [Indexed: 12/13/2022] Open
Abstract
The tight regulation of intracellular nucleotides is critical for the self-renewal and lineage specification of hematopoietic stem cells (HSCs). Nucleosides are major metabolite precursors for nucleotide biosynthesis and their availability in HSCs is dependent on their transport through specific membrane transporters. However, the role of nucleoside transporters in the differentiation of HSCs to the erythroid lineage and in red cell biology remains to be fully defined. Here, we show that the absence of the equilibrative nucleoside transporter (ENT1) in human red blood cells with a rare Augustine-null blood type is associated with macrocytosis, anisopoikilocytosis, an abnormal nucleotide metabolome, and deregulated protein phosphorylation. A specific role for ENT1 in human erythropoiesis was demonstrated by a defective erythropoiesis of human CD34+ progenitors following short hairpin RNA-mediated knockdown of ENT1. Furthermore, genetic deletion of ENT1 in mice was associated with reduced erythroid progenitors in the bone marrow, anemia, and macrocytosis. Mechanistically, we found that ENT1-mediated adenosine transport is critical for cyclic adenosine monophosphate homeostasis and the regulation of erythroid transcription factors. Notably, genetic investigation of 2 ENT1null individuals demonstrated a compensation by a loss-of-function variant in the ABCC4 cyclic nucleotide exporter. Indeed, pharmacological inhibition of ABCC4 in Ent1-/- mice rescued erythropoiesis. Overall, our results highlight the importance of ENT1-mediated nucleotide metabolism in erythropoiesis.
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Affiliation(s)
- Mahmoud Mikdar
- Université de Paris, Unité Mixte de Recherche (UMR) S1134, Biologie Intégrée du Globule Rouge, INSERM, Paris, France
- Centre National de Référence pour les Groupes Sanguins (CNRGS), Institut National de la Transfusion Sanguine, Paris, France
- Laboratoire d'Excellence (GR-Ex), Paris, France
| | - Pedro González-Menéndez
- Laboratoire d'Excellence (GR-Ex), Paris, France
- Institut de Génétique Moléculaire de Montpellier, Universite Montpellier, Centre National de la Recherche Scientifique (CNRS), Montpellier, France
| | - Xiaoli Cai
- Department of Biochemistry and Molecular Biology, University of Texas McGovern Medical School at Houston, Houston, TX
| | - Yujin Zhang
- Department of Biochemistry and Molecular Biology, University of Texas McGovern Medical School at Houston, Houston, TX
| | - Marion Serra
- Université de Paris, Unité Mixte de Recherche (UMR) S1134, Biologie Intégrée du Globule Rouge, INSERM, Paris, France
- Centre National de Référence pour les Groupes Sanguins (CNRGS), Institut National de la Transfusion Sanguine, Paris, France
- Laboratoire d'Excellence (GR-Ex), Paris, France
| | - Abdoul K Dembele
- Université de Paris, Unité Mixte de Recherche (UMR) S1134, Biologie Intégrée du Globule Rouge, INSERM, Paris, France
- Centre National de Référence pour les Groupes Sanguins (CNRGS), Institut National de la Transfusion Sanguine, Paris, France
- Laboratoire d'Excellence (GR-Ex), Paris, France
| | | | - Sylvia Sanquer
- INSERM UMR S1124, Université de Paris, Service de Biochimie Métabolomique et Protéomique, Hôpital Necker Enfants Malades, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Cerina Chhuon
- Université de Paris, Proteomics Platform 3P5-Necker, Structure Fédérative de Recherche Necker, INSERM US24/CNRS, Paris, France
| | - Ida Chiara Guerrera
- Université de Paris, Proteomics Platform 3P5-Necker, Structure Fédérative de Recherche Necker, INSERM US24/CNRS, Paris, France
| | - Marc Sitbon
- Institut de Génétique Moléculaire de Montpellier, Universite Montpellier, Centre National de la Recherche Scientifique (CNRS), Montpellier, France
| | - Olivier Hermine
- Laboratoire d'Excellence (GR-Ex), Paris, France
- Université de Paris, UMR 8147, CNRS, Paris, France
| | - Yves Colin
- Université de Paris, Unité Mixte de Recherche (UMR) S1134, Biologie Intégrée du Globule Rouge, INSERM, Paris, France
- Centre National de Référence pour les Groupes Sanguins (CNRGS), Institut National de la Transfusion Sanguine, Paris, France
- Laboratoire d'Excellence (GR-Ex), Paris, France
| | - Caroline Le Van Kim
- Université de Paris, Unité Mixte de Recherche (UMR) S1134, Biologie Intégrée du Globule Rouge, INSERM, Paris, France
- Centre National de Référence pour les Groupes Sanguins (CNRGS), Institut National de la Transfusion Sanguine, Paris, France
- Laboratoire d'Excellence (GR-Ex), Paris, France
| | - Sandrina Kinet
- Laboratoire d'Excellence (GR-Ex), Paris, France
- Institut de Génétique Moléculaire de Montpellier, Universite Montpellier, Centre National de la Recherche Scientifique (CNRS), Montpellier, France
| | | | - Yang Xia
- Department of Biochemistry and Molecular Biology, University of Texas McGovern Medical School at Houston, Houston, TX
| | - Thierry Peyrard
- Université de Paris, Unité Mixte de Recherche (UMR) S1134, Biologie Intégrée du Globule Rouge, INSERM, Paris, France
- Centre National de Référence pour les Groupes Sanguins (CNRGS), Institut National de la Transfusion Sanguine, Paris, France
- Laboratoire d'Excellence (GR-Ex), Paris, France
| | - Naomi Taylor
- Laboratoire d'Excellence (GR-Ex), Paris, France
- Institut de Génétique Moléculaire de Montpellier, Universite Montpellier, Centre National de la Recherche Scientifique (CNRS), Montpellier, France
- Pediatric Oncology Branch, National Cancer Institute, Center for Cancer Research, National Institutes of Health, Bethesda, MD
| | - Slim Azouzi
- Université de Paris, Unité Mixte de Recherche (UMR) S1134, Biologie Intégrée du Globule Rouge, INSERM, Paris, France
- Centre National de Référence pour les Groupes Sanguins (CNRGS), Institut National de la Transfusion Sanguine, Paris, France
- Laboratoire d'Excellence (GR-Ex), Paris, France
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12
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Ramón J, Vila-Julià F, Molina-Granada D, Molina-Berenguer M, Melià MJ, García-Arumí E, Torres-Torronteras J, Cámara Y, Martí R. Therapy Prospects for Mitochondrial DNA Maintenance Disorders. Int J Mol Sci 2021; 22:6447. [PMID: 34208592 PMCID: PMC8234938 DOI: 10.3390/ijms22126447] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 06/10/2021] [Accepted: 06/11/2021] [Indexed: 02/07/2023] Open
Abstract
Mitochondrial DNA depletion and multiple deletions syndromes (MDDS) constitute a group of mitochondrial diseases defined by dysfunctional mitochondrial DNA (mtDNA) replication and maintenance. As is the case for many other mitochondrial diseases, the options for the treatment of these disorders are rather limited today. Some aggressive treatments such as liver transplantation or allogeneic stem cell transplantation are among the few available options for patients with some forms of MDDS. However, in recent years, significant advances in our knowledge of the biochemical pathomechanisms accounting for dysfunctional mtDNA replication have been achieved, which has opened new prospects for the treatment of these often fatal diseases. Current strategies under investigation to treat MDDS range from small molecule substrate enhancement approaches to more complex treatments, such as lentiviral or adenoassociated vector-mediated gene therapy. Some of these experimental therapies have already reached the clinical phase with very promising results, however, they are hampered by the fact that these are all rare disorders and so the patient recruitment potential for clinical trials is very limited.
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Affiliation(s)
- Javier Ramón
- Research Group on Neuromuscular and Mitochondrial Diseases, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (J.R.); (F.V.-J.); (D.M.-G.); (M.M.-B.); (M.J.M.); (E.G.-A.); (J.T.-T.); (Y.C.)
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Ferran Vila-Julià
- Research Group on Neuromuscular and Mitochondrial Diseases, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (J.R.); (F.V.-J.); (D.M.-G.); (M.M.-B.); (M.J.M.); (E.G.-A.); (J.T.-T.); (Y.C.)
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - David Molina-Granada
- Research Group on Neuromuscular and Mitochondrial Diseases, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (J.R.); (F.V.-J.); (D.M.-G.); (M.M.-B.); (M.J.M.); (E.G.-A.); (J.T.-T.); (Y.C.)
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Miguel Molina-Berenguer
- Research Group on Neuromuscular and Mitochondrial Diseases, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (J.R.); (F.V.-J.); (D.M.-G.); (M.M.-B.); (M.J.M.); (E.G.-A.); (J.T.-T.); (Y.C.)
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Maria Jesús Melià
- Research Group on Neuromuscular and Mitochondrial Diseases, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (J.R.); (F.V.-J.); (D.M.-G.); (M.M.-B.); (M.J.M.); (E.G.-A.); (J.T.-T.); (Y.C.)
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Elena García-Arumí
- Research Group on Neuromuscular and Mitochondrial Diseases, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (J.R.); (F.V.-J.); (D.M.-G.); (M.M.-B.); (M.J.M.); (E.G.-A.); (J.T.-T.); (Y.C.)
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Javier Torres-Torronteras
- Research Group on Neuromuscular and Mitochondrial Diseases, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (J.R.); (F.V.-J.); (D.M.-G.); (M.M.-B.); (M.J.M.); (E.G.-A.); (J.T.-T.); (Y.C.)
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Yolanda Cámara
- Research Group on Neuromuscular and Mitochondrial Diseases, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (J.R.); (F.V.-J.); (D.M.-G.); (M.M.-B.); (M.J.M.); (E.G.-A.); (J.T.-T.); (Y.C.)
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Ramon Martí
- Research Group on Neuromuscular and Mitochondrial Diseases, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (J.R.); (F.V.-J.); (D.M.-G.); (M.M.-B.); (M.J.M.); (E.G.-A.); (J.T.-T.); (Y.C.)
- Biomedical Network Research Centre on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
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13
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AZT oxidative damage in the liver. Toxicology 2021. [DOI: 10.1016/b978-0-12-819092-0.00029-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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14
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Cox CR, Lynch S, Goldring C, Sharma P. Current Perspective: 3D Spheroid Models Utilizing Human-Based Cells for Investigating Metabolism-Dependent Drug-Induced Liver Injury. FRONTIERS IN MEDICAL TECHNOLOGY 2020; 2:611913. [PMID: 35047893 PMCID: PMC8757888 DOI: 10.3389/fmedt.2020.611913] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/04/2020] [Indexed: 12/21/2022] Open
Abstract
Drug-induced liver injury (DILI) remains a leading cause for the withdrawal of approved drugs. This has significant financial implications for pharmaceutical companies, places increasing strain on global health services, and causes harm to patients. For these reasons, it is essential that in-vitro liver models are capable of detecting DILI-positive compounds and their underlying mechanisms, prior to their approval and administration to patients or volunteers in clinical trials. Metabolism-dependent DILI is an important mechanism of drug-induced toxicity, which often involves the CYP450 family of enzymes, and is associated with the production of a chemically reactive metabolite and/or inefficient removal and accumulation of potentially toxic compounds. Unfortunately, many of the traditional in-vitro liver models fall short of their in-vivo counterparts, failing to recapitulate the mature hepatocyte phenotype, becoming metabolically incompetent, and lacking the longevity to investigate and detect metabolism-dependent DILI and those associated with chronic and repeat dosing regimens. Nevertheless, evidence is gathering to indicate that growing cells in 3D formats can increase the complexity of these models, promoting a more mature-hepatocyte phenotype and increasing their longevity, in vitro. This review will discuss the use of 3D in vitro models, namely spheroids, organoids, and perfusion-based systems to establish suitable liver models to investigate metabolism-dependent DILI.
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Affiliation(s)
- Christopher R. Cox
- Department of Pharmacology and Experimental Therapeutics, MRC Centre for Drug Safety Science, Institute of Systems, Molecular & Integrative Biology, University of Liverpool, Liverpool, United Kingdom
- Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
- *Correspondence: Christopher R. Cox
| | - Stephen Lynch
- Department of Pharmacology and Experimental Therapeutics, MRC Centre for Drug Safety Science, Institute of Systems, Molecular & Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Christopher Goldring
- Department of Pharmacology and Experimental Therapeutics, MRC Centre for Drug Safety Science, Institute of Systems, Molecular & Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Parveen Sharma
- Department of Pharmacology and Experimental Therapeutics, MRC Centre for Drug Safety Science, Institute of Systems, Molecular & Integrative Biology, University of Liverpool, Liverpool, United Kingdom
- Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
- Liverpool Centre for Cardiovascular Science, Liverpool, United Kingdom
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15
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Jolly CE, Douglas O, Kamalian L, Jenkins RE, Beckett AJ, Penman SL, Williams DP, Monshouwer M, Simic D, Snoeys J, Park BK, Chadwick AE. The utility of a differentiated preclinical liver model, HepaRG cells, in investigating delayed toxicity via inhibition of mitochondrial-replication induced by fialuridine. Toxicol Appl Pharmacol 2020; 403:115163. [PMID: 32730777 PMCID: PMC7456776 DOI: 10.1016/j.taap.2020.115163] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/21/2020] [Accepted: 07/24/2020] [Indexed: 01/29/2023]
Abstract
During its clinical development fialuridine caused liver toxicity and the death of five patients. This case remains relevant due to the continued development of mechanistically-related compounds against a back-drop of simple in vitro models which remain limited for the preclinical detection of such delayed toxicity. Here, proteomic investigation of a differentiated, HepaRG, and proliferating, HepG2 cell model was utilised to confirm the presence of the hENT1 transporter, thymidine kinase-1 and -2 (TK1, TK2) and thymidylate kinase, all essential in order to reproduce the cellular activation and disposition of fialuridine in the clinic. Acute metabolic modification assays could only identify mitochondrial toxicity in HepaRG cells following extended dosing, 2 weeks. Toxic effects were observed around 10 μM, which is within a range of 10-15 X approximate Cmax. HepaRG cell death was accompanied by a significant decrease in mitochondrial DNA content, indicative of inhibition of mitochondrial replication, and a subsequent reduction in mitochondrial respiration and the activity of mitochondrial respiratory complexes, not replicated in HepG2 cells. The structural epimer of fialuridine, included as a pharmacological negative control, was shown to have no cytotoxic effects in HepaRG cells up to 4 weeks. Overall, these comparative studies demonstrate the HepaRG model has translational relevance for fialuridine toxicity and therefore may have potential in investigating the inhibition of mitochondrial replication over prolonged exposure for other toxicants.
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Affiliation(s)
- Carol E Jolly
- MRC Centre for Drug Safety Science, The Department of Pharmacology and Therapeutics, The University of Liverpool, Ashton Street, Liverpool L69 3GE, UK
| | - Oisin Douglas
- MRC Centre for Drug Safety Science, The Department of Pharmacology and Therapeutics, The University of Liverpool, Ashton Street, Liverpool L69 3GE, UK
| | - Laleh Kamalian
- MRC Centre for Drug Safety Science, The Department of Pharmacology and Therapeutics, The University of Liverpool, Ashton Street, Liverpool L69 3GE, UK
| | - Rosalind E Jenkins
- MRC Centre for Drug Safety Science, The Department of Pharmacology and Therapeutics, The University of Liverpool, Ashton Street, Liverpool L69 3GE, UK
| | - Alison J Beckett
- Cellular and Molecular Physiology, The University of Liverpool, Crown Street, Liverpool L69 3BX, UK
| | - Sophie L Penman
- MRC Centre for Drug Safety Science, The Department of Pharmacology and Therapeutics, The University of Liverpool, Ashton Street, Liverpool L69 3GE, UK
| | - Dominic P Williams
- Innovative Medicines and Early Development, Drug Safety and Metabolism, Translational Safety, AstraZeneca, Cambridge, UK
| | - Mario Monshouwer
- Pharmacokinetics Dynamics and Metabolism, Janssen Research and Development, Beerse, Belgium
| | - Damir Simic
- Mechanistic and Investigative Toxicology, Janssen Research and Development, Spring House, PA, USA
| | - Jan Snoeys
- Pharmacokinetics Dynamics and Metabolism, Janssen Research and Development, Beerse, Belgium
| | - B Kevin Park
- MRC Centre for Drug Safety Science, The Department of Pharmacology and Therapeutics, The University of Liverpool, Ashton Street, Liverpool L69 3GE, UK
| | - Amy E Chadwick
- MRC Centre for Drug Safety Science, The Department of Pharmacology and Therapeutics, The University of Liverpool, Ashton Street, Liverpool L69 3GE, UK.
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16
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Sommerville EW, Dalla Rosa I, Rosenberg MM, Bruni F, Thompson K, Rocha M, Blakely EL, He L, Falkous G, Schaefer AM, Yu‐Wai‐Man P, Chinnery PF, Hedstrom L, Spinazzola A, Taylor RW, Gorman GS. Identification of a novel heterozygous guanosine monophosphate reductase (GMPR) variant in a patient with a late-onset disorder of mitochondrial DNA maintenance. Clin Genet 2020; 97:276-286. [PMID: 31600844 PMCID: PMC7004030 DOI: 10.1111/cge.13652] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 09/18/2019] [Accepted: 09/27/2019] [Indexed: 12/18/2022]
Abstract
Autosomal dominant progressive external ophthalmoplegia (adPEO) is a late-onset, Mendelian mitochondrial disorder characterised by paresis of the extraocular muscles, ptosis, and skeletal-muscle restricted multiple mitochondrial DNA (mtDNA) deletions. Although dominantly inherited, pathogenic variants in POLG, TWNK and RRM2B are among the most common genetic defects of adPEO, identification of novel candidate genes and the underlying pathomechanisms remains challenging. We report the clinical, genetic and molecular investigations of a patient who presented in the seventh decade of life with PEO. Oxidative histochemistry revealed cytochrome c oxidase-deficient fibres and occasional ragged red fibres showing subsarcolemmal mitochondrial accumulation in skeletal muscle, while molecular studies identified the presence of multiple mtDNA deletions. Negative candidate screening of known nuclear genes associated with PEO prompted diagnostic exome sequencing, leading to the prioritisation of a novel heterozygous c.547G>C variant in GMPR (NM_006877.3) encoding guanosine monophosphate reductase, a cytosolic enzyme required for maintaining the cellular balance of adenine and guanine nucleotides. We show that the novel c.547G>C variant causes aberrant splicing, decreased GMPR protein levels in patient skeletal muscle, proliferating and quiescent cells, and is associated with subtle changes in nucleotide homeostasis protein levels and evidence of disturbed mtDNA maintenance in skeletal muscle. Despite confirmation of GMPR deficiency, demonstrating marked defects of mtDNA replication or nucleotide homeostasis in patient cells proved challenging. Our study proposes that GMPR is the 19th locus for PEO and highlights the complexities of uncovering disease mechanisms in late-onset PEO phenotypes.
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Affiliation(s)
- Ewen W. Sommerville
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Ilaria Dalla Rosa
- Department of Clinical and Movement Neurosciences, UCL Queens Square Institute of Neurology, Royal Free CampusUniversity College LondonLondonUK
| | | | - Francesco Bruni
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
- Department of Biosciences, Biotechnologies and BiopharmaceuticsUniversity of Bari “ldo Moro”BariItaly
| | - Kyle Thompson
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Mariana Rocha
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Emma L. Blakely
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Langping He
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Gavin Falkous
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Andrew M. Schaefer
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Patrick Yu‐Wai‐Man
- NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of OphthalmologyLondonUK
- MRC Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
- Cambridge Centre for Brain Repair, Department of Clinical NeurosciencesUniversity of CambridgeCambridgeUK
| | - Patrick F. Chinnery
- Department of Clinical Neuroscience & Medical Research Council Mitochondrial Biology UnitSchool of Clinical Medicine, University of CambridgeCambridgeUK
| | - Lizbeth Hedstrom
- Department of BiologyBrandeis UniversityWalthamMA
- Department of ChemistryBrandeis University, 415 South St.WalthamMA
| | - Antonella Spinazzola
- Department of Clinical and Movement Neurosciences, UCL Queens Square Institute of Neurology, Royal Free CampusUniversity College LondonLondonUK
- MRC Centre for Neuromuscular DiseasesUCL Institute of Neurology and National Hospital for Neurology and NeurosurgeryLondonUK
| | - Robert W. Taylor
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
| | - Gráinne S. Gorman
- Wellcome Centre for Mitochondrial Research, Institute of NeuroscienceNewcastle UniversityNewcastle upon TyneUK
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17
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Managing the challenge of drug-induced liver injury: a roadmap for the development and deployment of preclinical predictive models. Nat Rev Drug Discov 2019; 19:131-148. [DOI: 10.1038/s41573-019-0048-x] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2019] [Indexed: 12/13/2022]
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18
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Hendriks DFG, Hurrell T, Riede J, van der Horst M, Tuovinen S, Ingelman-Sundberg M. Mechanisms of Chronic Fialuridine Hepatotoxicity as Revealed in Primary Human Hepatocyte Spheroids. Toxicol Sci 2019; 171:385-395. [PMID: 31505000 DOI: 10.1093/toxsci/kfz195] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 07/12/2019] [Accepted: 07/16/2019] [Indexed: 12/17/2022] Open
Abstract
AbstractDrug hepatotoxicity is often delayed in onset. An exemplar case is the chronic nature of fialuridine hepatotoxicity, which resulted in the deaths of several patients in clinical trials as preclinical studies failed to identify this human-specific hepatotoxicity. Conventional preclinical in vitro models are mainly designed to evaluate the risk of acute drug toxicity. Here, we evaluated the utility of 3D spheroid cultures of primary human hepatocytes (PHHs) to assess chronic drug hepatotoxicity events using fialuridine as an example. Fialuridine toxicity was only detectable after 7 days of repeated exposure. Clinical manifestations, including reactive oxygen species formation, lipid accumulation, and induction of apoptosis, were readily identified. Silencing the expression or activity of the human equilibrative nucleoside transporter 1 (ENT1), implicated in the mitochondrial transport of fialuridine, modestly protected PHH spheroids from fialuridine toxicity. Interference with the phosphorylation of fialuridine into the active triphosphate metabolites by silencing of thymidine kinase 2 (TK2) provided substantial protection, whereas simultaneous silencing of ENT1 and TK2 provided near-complete protection. Fialuridine-induced mitochondrial dysfunction was suggested by a decrease in the expression of mtDNA-encoded genes, which correlated with the onset of toxicity and was prevented under the simultaneous silencing of ENT1 and TK2. Furthermore, interference with the expression or activity of ribonucleotide reductase (RNR), which is critical to deoxyribonucleoside triphosphate (dNTP) pool homeostasis, resulted in selective potentiation of fialuridine toxicity. Our findings demonstrate the translational applicability of the PHH 3D spheroid model for assessing drug hepatotoxicity events which manifest only under chronic exposure conditions.
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Affiliation(s)
- Delilah F G Hendriks
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Tracey Hurrell
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Julia Riede
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Muriëlle van der Horst
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Sarianna Tuovinen
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm SE-171 77, Sweden
| | - Magnus Ingelman-Sundberg
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm SE-171 77, Sweden
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19
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Beninger P. Pharmacovigilance: An Overview. Clin Ther 2018; 40:1991-2004. [DOI: 10.1016/j.clinthera.2018.07.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 07/14/2018] [Accepted: 07/18/2018] [Indexed: 10/28/2022]
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20
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Guo Y, Chu X, Parrott NJ, Brouwer KL, Hsu V, Nagar S, Matsson P, Sharma P, Snoeys J, Sugiyama Y, Tatosian D, Unadkat JD, Huang SM, Galetin A. Advancing Predictions of Tissue and Intracellular Drug Concentrations Using In Vitro, Imaging and Physiologically Based Pharmacokinetic Modeling Approaches. Clin Pharmacol Ther 2018; 104:865-889. [PMID: 30059145 PMCID: PMC6197917 DOI: 10.1002/cpt.1183] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This white paper examines recent progress, applications, and challenges in predicting unbound and total tissue and intra/subcellular drug concentrations using in vitro and preclinical models, imaging techniques, and physiologically based pharmacokinetic (PBPK) modeling. Published examples, regulatory submissions, and case studies illustrate the application of different types of data in drug development to support modeling and decision making for compounds with transporter-mediated disposition, and likely disconnects between tissue and systemic drug exposure. The goals of this article are to illustrate current best practices and outline practical strategies for selecting appropriate in vitro and in vivo experimental methods to estimate or predict tissue and plasma concentrations, and to use these data in the application of PBPK modeling for human pharmacokinetic (PK), efficacy, and safety assessment in drug development.
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Affiliation(s)
- Yingying Guo
- Investigational Drug Disposition, Eli Lilly and Company, Lilly Corporate Center, DC0714, Indianapolis, IN 46285, USA; Tel: 317-277-4324
| | - Xiaoyan Chu
- Department of Pharmacokinetics, Pharmacodynamics and Drug Metabolism, Merck & Co., Inc., Kenilworth, New Jersey 07033, USA; 732-594-0977
| | - Neil J. Parrott
- Pharmaceutical Sciences, Pharmaceutical Research and Early Development, Roche Innovation Centre Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, CH-4070 Basel, Switzerland
| | - Kim L.R. Brouwer
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, CB #7569 Kerr Hall, Chapel Hill, NC 27599-7569, USA; Tel: (919) 962-7030
| | - Vicky Hsu
- Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, 10903 New Hampshire Ave, Silver Spring, MD 20993, USA; 301-796-1541
| | - Swati Nagar
- Temple University School of Pharmacy, Department of Pharmaceutical Sciences, 3307 N Broad Street, Philadelphia PA 19140, USA; 215-707-9110
| | - Pär Matsson
- Department of Pharmacy, Uppsala University, Box 580, SE-75123 Uppsala, Sweden +46-(0)18-471 46 30
| | - Pradeep Sharma
- Safety and ADME Translational Sciences, Drug Safety and Metabolism, IMED Biotech Unit, AstraZeneca R&D, Cambridge CB4 0WG, UK
| | - Jan Snoeys
- Department of Pharmacokinetics, Dynamics and Metabolism, Janssen R&D, Beerse, Belgium; Tel: +32-14606812
| | - Yuichi Sugiyama
- Sugiyama Laboratory, RIKEN Innovation Center, RIKEN Research Cluster for Innovation, Yokohama 230-0045, Japan; Tel: (045) 506-1814
| | - Daniel Tatosian
- Department of Pharmacokinetics, Pharmacodynamics and Drug Metabolism, Merck & Co., Inc., Kenilworth, New Jersey 07033, USA; 908-464-2375
| | - Jashvant D. Unadkat
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA; 206-685-2869
| | - Shiew-Mei Huang
- Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, 10903 New Hampshire Ave, Silver Spring, MD 20993, USA; 301-796-1541
| | - Aleksandra Galetin
- Centre for Applied Pharmacokinetic Research, School of Health Sciences, The University of Manchester, Manchester M13 9PT, UK; + 44-161-275-6886
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21
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Li Q, Zhou T, Wu F, Li N, Wang R, Zhao Q, Ma YM, Zhang JQ, Ma BL. Subcellular drug distribution: mechanisms and roles in drug efficacy, toxicity, resistance, and targeted delivery. Drug Metab Rev 2018; 50:430-447. [PMID: 30270675 DOI: 10.1080/03602532.2018.1512614] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
After administration, drug molecules usually enter target cells to access their intracellular targets. In eukaryotic cells, these targets are often located in organelles, including the nucleus, endoplasmic reticulum, mitochondria, lysosomes, Golgi apparatus, and peroxisomes. Each organelle type possesses unique biological features. For example, mitochondria possess a negative transmembrane potential, while lysosomes have an intraluminal delta pH. Other properties are common to several organelle types, such as the presence of ATP-binding cassette (ABC) or solute carrier-type (SLC) transporters that sequester or pump out xenobiotic drugs. Studies on subcellular drug distribution are critical to understand the efficacy and toxicity of drugs along with the body's resistance to them and to potentially offer hints for targeted subcellular drug delivery. This review summarizes the results of studies from 1990 to 2017 that examined the subcellular distribution of small molecular drugs. We hope this review will aid in the understanding of drug distribution within cells.
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Affiliation(s)
- Qiao Li
- a Department of Pharmacology , Shanghai University of Traditional Chinese Medicine , Shanghai , China
| | - Ting Zhou
- a Department of Pharmacology , Shanghai University of Traditional Chinese Medicine , Shanghai , China
| | - Fei Wu
- b Engineering Research Center of Modern Preparation Technology of TCM of Ministry of Education , Shanghai University of Traditional Chinese Medicine , Shanghai , China
| | - Na Li
- c Department of Chinese materia medica , School of Pharmacy , Shanghai , China
| | - Rui Wang
- b Engineering Research Center of Modern Preparation Technology of TCM of Ministry of Education , Shanghai University of Traditional Chinese Medicine , Shanghai , China
| | - Qing Zhao
- a Department of Pharmacology , Shanghai University of Traditional Chinese Medicine , Shanghai , China
| | - Yue-Ming Ma
- a Department of Pharmacology , Shanghai University of Traditional Chinese Medicine , Shanghai , China
| | - Ji-Quan Zhang
- b Engineering Research Center of Modern Preparation Technology of TCM of Ministry of Education , Shanghai University of Traditional Chinese Medicine , Shanghai , China
| | - Bing-Liang Ma
- a Department of Pharmacology , Shanghai University of Traditional Chinese Medicine , Shanghai , China
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22
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Damaraju VL, Kuzma M, Cass CE, Putman CT, Sawyer MB. Multitargeted kinase inhibitors imatinib, sorafenib and sunitinib perturb energy metabolism and cause cytotoxicity to cultured C2C12 skeletal muscle derived myotubes. Biochem Pharmacol 2018; 155:162-171. [PMID: 29983397 DOI: 10.1016/j.bcp.2018.07.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 07/01/2018] [Indexed: 12/12/2022]
Abstract
Tyrosine kinase inhibitors (TKIs) have advanced cancer treatment and prognosis but have also resulted in adverse effects such as fatigue, diarrhea, hypothyroidism, and other toxicities. We investigated TKI effects on skeletal muscle as a possible explanation of TKI induced fatigue. Changes in mitochondrial function due to inhibition of oxidative phosphorylation complexes, generation of superoxides, and inhibition of key transporters involved in uptake of glucose and/or nucleosides may result in alteration of energy metabolism and/or mitochondrial function. We investigated effects of imatinib, sorafenib and sunitinib on these processes in cultured C2C12 murine skeletal muscle cells. Imatinib, sorafenib and sunitinib were cytotoxic to C2C12 cells with IC50 values of 20, 8 and 8 µM, respectively. Imatinib stimulated glucose uptake and inhibited complex V activity by 35% at 50 µM. Sorafenib inhibited complex II/III and V with IC50 values of 32 and 28 µM, respectively. Sorafenib caused activation of caspase 3/7 and depolarization of mitochondrial membranes occurred very rapidly with complete loss at 5-10 µM. Sunitinib inhibited Complex I with an IC50 value of 38 µM and caused ATP depletion, caspase 3/7 activation, an increase in reactive oxygen species (ROS), and decreased nucleoside and glucose uptake. In conclusion, imatinib, sunitinib and sorafenib caused changes in mitochondrial complex activities, glucose and nucleoside uptake leading to decreased energy production and mitochondrial function in a skeletal muscle cell model, suggesting that these changes may play a role in fatigue, one of the most common adverse effects of TKIs.
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Affiliation(s)
- Vijaya L Damaraju
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave NW, Edmonton, Alberta T6G1Z2, Canada.
| | - Michelle Kuzma
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave NW, Edmonton, Alberta T6G1Z2, Canada.
| | - Carol E Cass
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave NW, Edmonton, Alberta T6G1Z2, Canada.
| | - Charles T Putman
- Faculty of Kinesiology, Sport, and Recreation
- Medicine & Dentistry, University of Alberta, Edmonton, Alberta T6G2H9, Canada.
| | - Michael B Sawyer
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave NW, Edmonton, Alberta T6G1Z2, Canada; Department of Medical Oncology, Cross Cancer Institute, 11560 University Avenue NW, Edmonton, Alberta T6G1Z2, Canada.
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23
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Molecular signature pathway of gene protein interaction in human mitochondrial DNA (mtDNA) metabolism linked disease. INDIAN JOURNAL OF MEDICAL SPECIALITIES 2018. [DOI: 10.1016/j.injms.2018.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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24
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Singh US, Mulamoottil VA, Chu CK. 2′-Fluoro-6′-methylene carbocyclic adenosine and its phosphoramidate prodrug: A novel anti-HBV agent, active against drug-resistant HBV mutants. Med Res Rev 2018; 38:977-1002. [DOI: 10.1002/med.21490] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 01/04/2018] [Accepted: 01/12/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Uma S. Singh
- Department of Pharmaceutical and Biomedical Sciences; University of Georgia; Athens GA USA
| | | | - Chung K. Chu
- Department of Pharmaceutical and Biomedical Sciences; University of Georgia; Athens GA USA
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25
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Patel M, Taskar KS, Zamek-Gliszczynski MJ. Importance of Hepatic Transporters in Clinical Disposition of Drugs and Their Metabolites. J Clin Pharmacol 2017; 56 Suppl 7:S23-39. [PMID: 27385177 DOI: 10.1002/jcph.671] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 10/16/2015] [Indexed: 01/04/2023]
Abstract
This review provides a practical clinical perspective on the relevance of hepatic transporters in pharmacokinetics and drug-drug interactions (DDIs). Special emphasis is placed on transporters with clear relevance to clinical DDIs, efficacy, and safety. Basolateral OATP1B1 and 1B3 emerged as important hepatic drug uptake pathways, sites for systemic DDIs, and sources of pharmacogenetic variability. As the first step in hepatic drug removal from the circulation, OATPs are an important determinant of systemic pharmacokinetics, specifically influencing systemic absorption, clearance, and hepatic distribution for subsequent metabolism and/or excretion. Biliary excretion of parent drugs is a less prevalent clearance pathway than metabolism or urinary excretion, but BCRP and MRP2 are critically important to biliary/fecal elimination of drug metabolites. Inhibition of biliary excretion is typically not apparent at the level of systemic pharmacokinetics but can markedly increase liver exposure. Basolateral efflux transporters MRP3 and MRP4 mediate excretion of parent drugs and, more commonly, polar metabolites from hepatocytes into blood. Basolateral excretion is an area in need of further clinical investigation, which will necessitate studies more complex than just systemic pharmacokinetics. Clinical relevance of hepatic uptake is relatively well appreciated, and clinical consequences of hepatic excretion (biliary and basolateral) modulation remain an active research area.
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Affiliation(s)
- Mitesh Patel
- Mechanistic Safety and Disposition, GlaxoSmithKline, King of Prussia, PA, USA
| | - Kunal S Taskar
- Mechanistic Safety and Disposition, GlaxoSmithKline, Ware, Hertfordshire, UK
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26
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A Single Zidovudine (AZT) Administration Delays Hepatic Cell Proliferation by Altering Oxidative State in the Regenerating Rat Liver. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:8356175. [PMID: 28479956 PMCID: PMC5396445 DOI: 10.1155/2017/8356175] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 02/01/2017] [Accepted: 02/21/2017] [Indexed: 12/29/2022]
Abstract
The 3′-azido-3′-deoxythymidine or Zidovudine (AZT) was the first antiretroviral drug used in the treatment of HIV patients, which has good effectiveness but also hepatotoxic side effects that include cell cycle arrest and oxidative/nitrative mitochondrial damage. Whether such an oxidative damage may affect the proliferative-regenerative capacity of liver remains to be clearly specified at doses commonly used in the clinical practice. In this study, we described the oxidative-proliferative effect of AZT administered at a common clinical dose in rat liver submitted to 70% partial hepatectomy (PH). The results indicate that AZT significantly decreased DNA synthesis and the number of mitosis in liver subjected to PH in a synchronized way with the promotion of organelle-selective lipid peroxidation events (especially those observed in plasma membrane and cytosolic fractions) and with liver enzyme release to the bloodstream. Then at the dose used in clinical practice AZT decreased liver regeneration but stimulates oxidative events involved during the proliferation process in a way that each membrane system inside the cell preserves its integrity in order to maintain the cell proliferative process. Here, the induction of large amounts of free ammonia in the systemic circulation could become a factor capable of mediating the deleterious effects of AZT on PH-induced rat liver regeneration.
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27
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Zhong XZ, Zou Y, Sun X, Dong G, Cao Q, Pandey A, Rainey JK, Zhu X, Dong XP. Inhibition of Transient Receptor Potential Channel Mucolipin-1 (TRPML1) by Lysosomal Adenosine Involved in Severe Combined Immunodeficiency Diseases. J Biol Chem 2017; 292:3445-3455. [PMID: 28087698 DOI: 10.1074/jbc.m116.743963] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 01/09/2017] [Indexed: 11/06/2022] Open
Abstract
Impaired adenosine homeostasis has been associated with numerous human diseases. Lysosomes are referred to as the cellular recycling centers that generate adenosine by breaking down nucleic acids or ATP. Recent studies have suggested that lysosomal adenosine overload causes lysosome defects that phenocopy patients with mutations in transient receptor potential channel mucolipin-1 (TRPML1), a lysosomal Ca2+ channel, suggesting that lysosomal adenosine overload may impair TRPML1 and then lead to subsequent lysosomal dysfunction. In this study, we demonstrate that lysosomal adenosine is elevated by deleting adenosine deaminase (ADA), an enzyme responsible for adenosine degradation. We also show that lysosomal adenosine accumulation inhibits TRPML1, which is rescued by overexpressing ENT3, the adenosine transporter situated in the lysosome membrane. Moreover, ADA deficiency results in lysosome enlargement, alkalinization, and dysfunction. These are rescued by activating TRPML1. Importantly, ADA-deficient B-lymphocytes are more vulnerable to oxidative stress, and this was rescued by TRPML1 activation. Our data suggest that lysosomal adenosine accumulation impairs lysosome function by inhibiting TRPML1 and subsequently leads to cell death in B-lymphocytes. Activating TRPML1 could be a new therapeutic strategy for those diseases.
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Affiliation(s)
| | | | - Xue Sun
- Departments of Physiology and Biophysics; Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, 130024 Jilin, China
| | | | - Qi Cao
- Departments of Physiology and Biophysics
| | - Aditya Pandey
- Biochemistry and Molecular Biology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College Street, Halifax, Nova Scotia B3H 4R2, Canada
| | - Jan K Rainey
- Biochemistry and Molecular Biology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College Street, Halifax, Nova Scotia B3H 4R2, Canada; Department of Chemistry, Dalhousie University, 6274 Coburg Road, Halifax, Nova Scotia B3H 4R2, Canada
| | - Xiaojuan Zhu
- Key Laboratory of Molecular Epigenetics of Ministry of Education, Institute of Cytology and Genetics, Northeast Normal University, Changchun, 130024 Jilin, China
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28
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Neurotoxicity in the Post-HAART Era: Caution for the Antiretroviral Therapeutics. Neurotox Res 2016; 30:677-697. [PMID: 27364698 DOI: 10.1007/s12640-016-9646-0] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 06/15/2016] [Accepted: 06/20/2016] [Indexed: 12/19/2022]
Abstract
Despite the advent of highly active antiretroviral therapy (HAART), HIV-associated neurological disorders (HAND) remain a major challenge in human immunodeficiency virus (HIV) treatment. The early implementation of HAART in the infected individuals helps suppress the viral replication in the plasma and other compartments. Several studies also report the beneficial effect of drugs that successfully penetrate central nervous system (CNS). However, recent data in both clinical setup and in in vitro studies indicate CNS toxicity of the antiretrovirals (ARVs). Although the evidence is limited, correlation between prolonged use of ARVs and neurotoxicity strongly suggests that it is essential to study the underlying mechanisms responsible for such toxicity. Furthermore, closer attention toward clinical outcomes is required to screen various ARV regimens for their association with HAND and other comorbidities. A growing body of literature also indicates a possible role of accelerated aging in the antiretroviral therapy-associated neurotoxicity. Lastly, owing to high pill burden, multiple drugs in the HIV treatment also invite a possible role of drug-drug interaction via various cytochrome P450 enzymes. The particular emphasis of this review is to highlight the need to identify alternative approaches in reducing the CNS toxicity of the ARV drugs in HIV-infected individuals.
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29
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Dalla Rosa I, Cámara Y, Durigon R, Moss CF, Vidoni S, Akman G, Hunt L, Johnson MA, Grocott S, Wang L, Thorburn DR, Hirano M, Poulton J, Taylor RW, Elgar G, Martí R, Voshol P, Holt IJ, Spinazzola A. MPV17 Loss Causes Deoxynucleotide Insufficiency and Slow DNA Replication in Mitochondria. PLoS Genet 2016; 12:e1005779. [PMID: 26760297 PMCID: PMC4711891 DOI: 10.1371/journal.pgen.1005779] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 12/08/2015] [Indexed: 11/21/2022] Open
Abstract
MPV17 is a mitochondrial inner membrane protein whose dysfunction causes mitochondrial DNA abnormalities and disease by an unknown mechanism. Perturbations of deoxynucleoside triphosphate (dNTP) pools are a recognized cause of mitochondrial genomic instability; therefore, we determined DNA copy number and dNTP levels in mitochondria of two models of MPV17 deficiency. In Mpv17 ablated mice, liver mitochondria showed substantial decreases in the levels of dGTP and dTTP and severe mitochondrial DNA depletion, whereas the dNTP pool was not significantly altered in kidney and brain mitochondria that had near normal levels of DNA. The shortage of mitochondrial dNTPs in Mpv17-/- liver slows the DNA replication in the organelle, as evidenced by the elevated level of replication intermediates. Quiescent fibroblasts of MPV17-mutant patients recapitulate key features of the primary affected tissue of the Mpv17-/- mice, displaying virtual absence of the protein, decreased dNTP levels and mitochondrial DNA depletion. Notably, the mitochondrial DNA loss in the patients’ quiescent fibroblasts was prevented and rescued by deoxynucleoside supplementation. Thus, our study establishes dNTP insufficiency in the mitochondria as the cause of mitochondrial DNA depletion in MPV17 deficiency, and identifies deoxynucleoside supplementation as a potential therapeutic strategy for MPV17-related disease. Moreover, changes in the expression of factors involved in mitochondrial deoxynucleotide homeostasis indicate a remodeling of nucleotide metabolism in MPV17 disease models, which suggests mitochondria lacking functional MPV17 have a restricted purine mitochondrial salvage pathway. Mitochondrial DNA depletion syndrome (MDS) is a genetically heterogeneous condition characterized by a decrease of mitochondrial DNA (mtDNA) copy number and decreased activities of respiratory chain enzymes. Depletion of mtDNA has been associated with mutations in several genes, which encode either proteins directly involved in mtDNA replication or factors regulating the homeostasis of the mitochondrial deoxynucleotide pool. However, for some genes the mechanism linking mutations and mtDNA depletion is not known. One such gene is MPV17, whose loss-of-function causes mtDNA abnormalities in human, mouse and yeast. Here we show that MPV17 dysfunction leads to a shortage of the precursors for DNA synthesis in the mitochondria, slowing DNA replication in the organelle. Not only does mtDNA copy number correlate with dNTP pool size in both mouse tissues and human cells, deoxynucleoside supplementation of the growth medium prevents depletion and restores mtDNA copy number in quiescent MPV17-deficient cells. Hence, our study links MPV17 deficiency, insufficiency of mitochondrial dNTPs, and slow replication in mitochondria to depletion of mtDNA manifesting in the human disease, and places MPV17-related disease firmly in the category of mtDNA disorders caused by deoxynucleotide perturbation. The prevention and reversal of mtDNA loss in MPV17 patient-derived cells identifies potential therapeutic strategy for a currently untreatable disease.
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Affiliation(s)
| | - Yolanda Cámara
- Laboratory of Mitochondrial Disorders, Vall d’Hebron Institut de Recerca, Universitat Autònoma de Barcelona, Barcelona, Catalonia
- Biomedical Network Research Centre on Rare Diseases, Instituto de Salud Carlos III, Madrid, Spain
| | | | | | - Sara Vidoni
- MRC Mitochondrial Biology Unit, Wellcome Trust-MRC Building, Cambridge, United Kingdom
| | - Gokhan Akman
- MRC Mill Hill Laboratory, London, United Kingdom
| | - Lilian Hunt
- MRC Mill Hill Laboratory, London, United Kingdom
| | - Mark A. Johnson
- MRC Mitochondrial Biology Unit, Wellcome Trust-MRC Building, Cambridge, United Kingdom
| | - Sarah Grocott
- Mitochondrial Genetics Group, Nuffield Department of Obstetrics and Gynaecology, Women's Centre, The John Radcliffe Hospital, Oxford, United Kingdom
| | - Liya Wang
- Department of Anatomy, Physiology and Biochemistry, The Swedish University of Agricultural Sciences, Biomedical Center, Uppsala, Sweden
| | - David R. Thorburn
- Murdoch Childrens Research Institute and University of Melbourne Department of Paediatrics, Royal Children's Hospital, Flemington Road, Parkville, Victoria, Australia
| | - Michio Hirano
- Department of Neurology, Columbia University Medical Center, New York, New York, United States of America
| | - Joanna Poulton
- Mitochondrial Genetics Group, Nuffield Department of Obstetrics and Gynaecology, Women's Centre, The John Radcliffe Hospital, Oxford, United Kingdom
| | - Robert W. Taylor
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, The Medical School, Newcastle upon Tyne, United Kingdom
| | - Greg Elgar
- MRC Mill Hill Laboratory, London, United Kingdom
| | - Ramon Martí
- Laboratory of Mitochondrial Disorders, Vall d’Hebron Institut de Recerca, Universitat Autònoma de Barcelona, Barcelona, Catalonia
- Biomedical Network Research Centre on Rare Diseases, Instituto de Salud Carlos III, Madrid, Spain
| | - Peter Voshol
- Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - Ian J. Holt
- MRC Mill Hill Laboratory, London, United Kingdom
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30
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Cabrera-Pérez R, Torres-Torronteras J, Vila-Julià F, Ortega FJ, Cámara Y, Barquinero J, Martí R. Prospective therapeutic approaches in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). Expert Opin Orphan Drugs 2015. [DOI: 10.1517/21678707.2015.1090307] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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31
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Franzolin E, Salata C, Bianchi V, Rampazzo C. The Deoxynucleoside Triphosphate Triphosphohydrolase Activity of SAMHD1 Protein Contributes to the Mitochondrial DNA Depletion Associated with Genetic Deficiency of Deoxyguanosine Kinase. J Biol Chem 2015; 290:25986-96. [PMID: 26342080 PMCID: PMC4646252 DOI: 10.1074/jbc.m115.675082] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Indexed: 11/22/2022] Open
Abstract
The dNTP triphosphohydrolase SAMHD1 is a nuclear antiviral host restriction factor limiting HIV-1 infection in macrophages and a major regulator of dNTP concentrations in human cells. In normal human fibroblasts its expression increases during quiescence, contributing to the small dNTP pool sizes of these cells. Down-regulation of SAMHD1 by siRNA expands all four dNTP pools, with dGTP undergoing the largest relative increase. The deoxyguanosine released by SAMHD1 from dGTP can be phosphorylated inside mitochondria by deoxyguanosine kinase (dGK) or degraded in the cytosol by purine nucleoside phosphorylase. Genetic mutations of dGK cause mitochondrial (mt) DNA depletion in noncycling cells and hepato-cerebral mtDNA depletion syndrome in humans. We studied if SAMHD1 and dGK interact in the regulation of the dGTP pool during quiescence employing dGK-mutated skin fibroblasts derived from three unrelated patients. In the presence of SAMHD1 quiescent mutant fibroblasts manifested mt dNTP pool imbalance and mtDNA depletion. When SAMHD1 was silenced by siRNA transfection the composition of the mt dNTP pool approached that of the controls, and mtDNA copy number increased, compensating the depletion to various degrees in the different mutant fibroblasts. Chemical inhibition of purine nucleoside phosphorylase did not improve deoxyguanosine recycling by dGK in WT cells. We conclude that the activity of SAMHD1 contributes to the pathological phenotype of dGK deficiency. Our results prove the importance of SAMHD1 in the regulation of all dNTP pools and suggest that dGK inside mitochondria has the function of recycling the deoxyguanosine derived from endogenous dGTP degraded by SAMHD1 in the nucleus.
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Affiliation(s)
- Elisa Franzolin
- From the Department of Biology, University of Padova, 35131 Padova, Italy and
| | - Cristiano Salata
- Department of Molecular Medicine, University of Padova, 35121 Padova, Italy
| | - Vera Bianchi
- From the Department of Biology, University of Padova, 35131 Padova, Italy and
| | - Chiara Rampazzo
- From the Department of Biology, University of Padova, 35131 Padova, Italy and
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32
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Demir M, Laywell ED. Neurotoxic effects of AZT on developing and adult neurogenesis. Front Neurosci 2015; 9:93. [PMID: 25852464 PMCID: PMC4367529 DOI: 10.3389/fnins.2015.00093] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 03/05/2015] [Indexed: 11/18/2022] Open
Abstract
Azidothymidine (AZT) is a synthetic, chain-terminating nucleoside analog used to treat HIV-1 infection. While AZT is not actively transported across the blood brain barrier, it does accumulate at high levels in cerebrospinal fluid, and subsequently diffuses into the overlying parenchyma. Due to the close anatomical proximity of the neurogenic niches to the ventricular system, we hypothesize that diffusion from CSF exposes neural stem/progenitor cells and their progeny to biologically relevant levels of AZT sufficient to perturb normal cell functions. We employed in vitro and in vivo models of mouse neurogenesis in order to assess the effects of AZT on developing and adult neurogenesis. Using in vitro assays we show that AZT reduces the population expansion potential of neural stem/progenitor cells by inducing senescence. Additionally, in a model of in vitro neurogenesis AZT severely attenuates neuroblast production. These effects are mirrored in vivo by clinically-relevant animal models. We show that in utero AZT exposure perturbs both population expansion and neurogenesis among neural stem/progenitor cells. Additionally, a short-term AZT regimen in adult mice suppresses subependymal zone neurogenesis. These data reveal novel negative effects of AZT on neural stem cell biology. Given that the sequelae of HIV infection often include neurologic deficits—subsumed under AIDS Dementia Complex (Brew, 1999)—it is important to determine to what extent AZT negatively affects neurological function in ways that contribute to, or exacerbate, ADC in order to avoid attributing iatrogenic drug effects to the underlying disease process, and thereby skewing the risk/benefit analysis of AZT therapy.
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Affiliation(s)
- Meryem Demir
- Department of Anatomy and Cell Biology, College of Medicine, University of Florida Gainesville, FL, USA
| | - Eric D Laywell
- Department of Biomedical Sciences, College of Medicine, Florida State University Tallahassee, FL, USA
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33
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Di Noia MA, Todisco S, Cirigliano A, Rinaldi T, Agrimi G, Iacobazzi V, Palmieri F. The human SLC25A33 and SLC25A36 genes of solute carrier family 25 encode two mitochondrial pyrimidine nucleotide transporters. J Biol Chem 2014; 289:33137-48. [PMID: 25320081 DOI: 10.1074/jbc.m114.610808] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The human genome encodes 53 members of the solute carrier family 25 (SLC25), also called the mitochondrial carrier family, many of which have been shown to transport inorganic anions, amino acids, carboxylates, nucleotides, and coenzymes across the inner mitochondrial membrane, thereby connecting cytosolic and matrix functions. Here two members of this family, SLC25A33 and SLC25A36, have been thoroughly characterized biochemically. These proteins were overexpressed in bacteria and reconstituted in phospholipid vesicles. Their transport properties and kinetic parameters demonstrate that SLC25A33 transports uracil, thymine, and cytosine (deoxy)nucleoside di- and triphosphates by an antiport mechanism and SLC25A36 cytosine and uracil (deoxy)nucleoside mono-, di-, and triphosphates by uniport and antiport. Both carriers also transported guanine but not adenine (deoxy)nucleotides. Transport catalyzed by both carriers was saturable and inhibited by mercurial compounds and other inhibitors of mitochondrial carriers to various degrees. In confirmation of their identity (i) SLC25A33 and SLC25A36 were found to be targeted to mitochondria and (ii) the phenotypes of Saccharomyces cerevisiae cells lacking RIM2, the gene encoding the well characterized yeast mitochondrial pyrimidine nucleotide carrier, were overcome by expressing SLC25A33 or SLC25A36 in these cells. The main physiological role of SLC25A33 and SLC25A36 is to import/export pyrimidine nucleotides into and from mitochondria, i.e. to accomplish transport steps essential for mitochondrial DNA and RNA synthesis and breakdown.
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Affiliation(s)
- Maria Antonietta Di Noia
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, via Orabona 4, 70125 Bari, Italy, Department of Sciences, University of Basilicata, via N. Sauro 85, 85100 Potenza, Italy
| | - Simona Todisco
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, via Orabona 4, 70125 Bari, Italy
| | - Angela Cirigliano
- Pasteur Institute-Cenci Bolognetti Foundation, Department of Biology and Biotechnology "Charles Darwin," University of Rome La Sapienza, 00185 Rome, Italy, Associazione Gian Franco Lupo "Un Sorriso alla Vita," ASM Azienda Sanitaria Locale di Matera, via Montescaglioso 75100 Matera, Italy, and
| | - Teresa Rinaldi
- Pasteur Institute-Cenci Bolognetti Foundation, Department of Biology and Biotechnology "Charles Darwin," University of Rome La Sapienza, 00185 Rome, Italy
| | - Gennaro Agrimi
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, via Orabona 4, 70125 Bari, Italy
| | - Vito Iacobazzi
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, via Orabona 4, 70125 Bari, Italy, Center of Excellence in Comparative Genomics, University of Bari, via Orabona 4, 70125 Bari, Italy
| | - Ferdinando Palmieri
- From the Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, via Orabona 4, 70125 Bari, Italy, Center of Excellence in Comparative Genomics, University of Bari, via Orabona 4, 70125 Bari, Italy
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34
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Sahin U, Karikó K, Türeci Ö. mRNA-based therapeutics--developing a new class of drugs. Nat Rev Drug Discov 2014; 13:759-80. [PMID: 25233993 DOI: 10.1038/nrd4278] [Citation(s) in RCA: 1367] [Impact Index Per Article: 136.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In vitro transcribed (IVT) mRNA has recently come into focus as a potential new drug class to deliver genetic information. Such synthetic mRNA can be engineered to transiently express proteins by structurally resembling natural mRNA. Advances in addressing the inherent challenges of this drug class, particularly related to controlling the translational efficacy and immunogenicity of the IVTmRNA, provide the basis for a broad range of potential applications. mRNA-based cancer immunotherapies and infectious disease vaccines have entered clinical development. Meanwhile, emerging novel approaches include in vivo delivery of IVT mRNA to replace or supplement proteins, IVT mRNA-based generation of pluripotent stem cells and genome engineering using IVT mRNA-encoded designer nucleases. This Review provides a comprehensive overview of the current state of mRNA-based drug technologies and their applications, and discusses the key challenges and opportunities in developing these into a new class of drugs.
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Affiliation(s)
- Ugur Sahin
- 1] TRON Translational Oncology at the University Medical Center of the Johannes Gutenberg University, Langenbeckstrasse 1, 55131 Mainz, Germany. [2] BioNTech Corporation, An der Goldgrube 12, 55131 Mainz, Germany
| | - Katalin Karikó
- 1] BioNTech Corporation, An der Goldgrube 12, 55131 Mainz, Germany. [2] Department of Neurosurgery, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Özlem Türeci
- TRON Translational Oncology at the University Medical Center of the Johannes Gutenberg University, Langenbeckstrasse 1, 55131 Mainz, Germany
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Nucleotides and Nucleosides: Transport, Metabolism, and Signaling Function of Extracellular ATP. PROGRESS IN BOTANY 2014. [DOI: 10.1007/978-3-642-38797-5_4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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36
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Cámara Y, González-Vioque E, Scarpelli M, Torres-Torronteras J, Martí R. Feeding the deoxyribonucleoside salvage pathway to rescue mitochondrial DNA. Drug Discov Today 2013; 18:950-7. [DOI: 10.1016/j.drudis.2013.06.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 05/27/2013] [Accepted: 06/19/2013] [Indexed: 12/16/2022]
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Young JD, Yao SYM, Baldwin JM, Cass CE, Baldwin SA. The human concentrative and equilibrative nucleoside transporter families, SLC28 and SLC29. Mol Aspects Med 2013; 34:529-47. [PMID: 23506887 DOI: 10.1016/j.mam.2012.05.007] [Citation(s) in RCA: 244] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 04/11/2012] [Indexed: 12/23/2022]
Abstract
Nucleoside transport in humans is mediated by members of two unrelated protein families, the SLC28 family of cation-linked concentrative nucleoside transporters (CNTs) and the SLC29 family of energy-independent, equilibrative nucleoside transporters (ENTs). These families contain three and four members, respectively, which differ both in the stoichiometry of cation coupling and in permeant selectivity. Together, they play key roles in nucleoside and nucleobase uptake for salvage pathways of nucleotide synthesis. Moreover, they facilitate cellular uptake of several nucleoside and nucleobase drugs used in cancer chemotherapy and treatment of viral infections. Thus, the transporter content of target cells can represent a key determinant of the response to treatment. In addition, by regulating the concentration of adenosine available to cell surface receptors, nucleoside transporters modulate many physiological processes ranging from neurotransmission to cardiovascular activity. This review describes the molecular and functional properties of the two transporter families, with a particular focus on their physiological roles in humans and relevance to disease treatment.
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Affiliation(s)
- James D Young
- Membrane Protein Research Group, Edmonton, Alberta, Canada T6G 2H7.
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38
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Gil L, Pérez D, Tápanes R, Pérez J, Grune T. Does mitochondrial dysfunction during antiretroviral therapy in human immunodeficiency virus infection suggest antioxidant supplementation as a beneficial option? Redox Rep 2013; 10:113-9. [PMID: 16156949 DOI: 10.1179/135100005x38905] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Over the last few years, a relative decline of the morbidity and mortality of human immunodeficiency virus (HIV) infection in industrialised countries has been observed due to the use of a potent combined therapy known as high active antiretroviral therapies (HAARTs). It has led to a decrease of viral load and a quantitative and qualitative improvement of immune function in patients, especially CD4+ T-lymphocyte count, having as a consequence a decrease of infectious complications and a global clinical improvement. Besides the positive effects of HAARTs on immune and metabolic alterations during HIV infection, it has been reported that the commonly used drugs AZT, ddI, and ddC are toxic to hepatocytes. Recent reports continue to point to the mitochondria as targets for toxicity. The prevalence of these symptoms is continued during acquired immunodeficiency syndrome (AIDS). The effects of oxidative stress occurring as a consequence of mitochondrial toxicity may amplify some of the pathophysiological and phenotypic events during infection. Mitochondrial stabilisation and antioxidative strategies are possible new therapeutic aims since the antiretroviral treatment is prolonged with increased longevity from AIDS, which has become a more manageable chronic illness. The aim of the present review article is to summarize the current knowledge about mitochondrial dysfunction during HAART and its consequence for patients with chronic treatment. Oxidative stress may serve as one pathway for cellular damage in AIDS and its treatment. One important future goal is to prevent or attenuate the side effects of HAART so that improved disease management can be achieved.
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Affiliation(s)
- Lizette Gil
- Laboratory of Clinical Pharmacology, Hospital, Institute of Tropical Medicine Pedro Kourí (IPK), Ciudad Habana, Cuba
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39
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Prasad B, Lai Y, Lin Y, Unadkat JD. Interindividual variability in the hepatic expression of the human breast cancer resistance protein (BCRP/ABCG2): effect of age, sex, and genotype. J Pharm Sci 2013; 102:787-93. [PMID: 23280364 DOI: 10.1002/jps.23436] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 11/08/2012] [Accepted: 12/07/2012] [Indexed: 12/21/2022]
Abstract
Breast cancer resistance protein (BCRP), an efflux transporter expressed at the bile canalicular membrane, is responsible for the biliary clearance of many drugs. Data on the interindividual variability of hepatic BCRP expression are needed for in vitro to in vivo extrapolation of the biliary clearance of a BCRP substrate drug. Therefore, we measured the expression of BCRP in human livers (n = 65) by liquid chromatography coupled with tandem mass spectrometry. A calibration curve was generated using a synthetic signature peptide (SSLLDVLAAR) as the calibrator and the corresponding synthetic stable isotope-labeled peptide as the internal standard. The analytical method was accurate and precise. BCRP expression in 50 livers, where it was measurable, was 137.9 ± 42.1 atmol/µg of membrane protein (range 69.7-246.4 atmol/µg of membrane protein). BCRP expression was not associated with age (7-70 years), sex, or mRNA expression. BCRP expression in livers with the variant C421A (rs2231142) allele (14 heterozygotes, two homozygotes; among these, eight livers were below lower limit of quantification) was significantly lower than that in the wild-type livers (p < 0.002). Integration of these data with data on the hepatic expression of other transporters will allow refinement of physiologically based pharmacokinetic models to predict the pharmacokinetics, hepatic exposure, and drug-drug interactions of drugs (and/or their metabolites).
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Affiliation(s)
- Bhagwat Prasad
- Department of Pharmaceutics, University of Washington, Seattle, Washington 98195, USA
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40
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2′-Fluoro-6′-methylene-carbocyclic adenosine phosphoramidate (FMCAP) prodrug: In vitro anti-HBV activity against the lamivudine–entecavir resistant triple mutant and its mechanism of action. Bioorg Med Chem Lett 2013; 23:503-6. [PMID: 23237841 DOI: 10.1016/j.bmcl.2012.11.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 11/08/2012] [Indexed: 12/30/2022]
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41
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Shitara Y, Nakamichi N, Norioka M, Shima H, Kato Y, Horie T. Role of organic cation/carnitine transporter 1 in uptake of phenformin and inhibitory effect on complex I respiration in mitochondria. Toxicol Sci 2012; 132:32-42. [PMID: 23221006 DOI: 10.1093/toxsci/kfs330] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Phenformin causes lactic acidosis in clinical situations due to inhibition of mitochondrial respiratory chain complex I. It is reportedly taken up by hepatocytes and exhibits mitochondrial toxicity in the liver. In this study, uptake of phenformin and [(14)C]tetraethylammonium (TEA) and complex I inhibition by phenformin were examined in isolated liver and heart mitochondria. Uptake of phenformin into isolated rat liver mitochondria was higher than that into heart mitochondria. It was inhibited by several cat ionic compounds, which suggests the involvement of multispecific transport system(s). Similar characteristics were also observed for uptake of TEA; however, uptake of phenformin into mitochondria of organic cation/carnitine transporter 1 (OCTN1) knockout mice was lower than that in wild-type mice, whereas uptake of TEA was comparable between the two strains, suggesting the involvement of distinct transport mechanisms for these two cations in mitochondria. Inhibition by phenformin of oxygen consumption via complex I respiration in isolated rat liver mitochondria was greater than that in heart mitochondria, whereas inhibitory effect of phenformin on complex I respiration was similar in inside-out structured submitochondrial particles prepared from rat livers and hearts. Lactic acidosis provoked by iv infusion of phenformin was weaker in octn1(-/-) mice than that in wild-type mice. These observations suggest that uptake of phenformin into liver mitochondria is at least partly mediated by OCTN1 and functionally relevant to its inhibition potential of complex I respiration. This study was, thus, the first to demonstrate OCTN1-mediated mitochondrial transport and toxicity of biguanide in vivo in rodents.
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Affiliation(s)
- Yoshihisa Shitara
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
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42
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Arnold JJ, Sharma SD, Feng JY, Ray AS, Smidansky ED, Kireeva ML, Cho A, Perry J, Vela JE, Park Y, Xu Y, Tian Y, Babusis D, Barauskus O, Peterson BR, Gnatt A, Kashlev M, Zhong W, Cameron CE. Sensitivity of mitochondrial transcription and resistance of RNA polymerase II dependent nuclear transcription to antiviral ribonucleosides. PLoS Pathog 2012; 8:e1003030. [PMID: 23166498 PMCID: PMC3499576 DOI: 10.1371/journal.ppat.1003030] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Accepted: 09/28/2012] [Indexed: 12/29/2022] Open
Abstract
Ribonucleoside analogues have potential utility as anti-viral, -parasitic, -bacterial and -cancer agents. However, their clinical applications have been limited by off target effects. Development of antiviral ribonucleosides for treatment of hepatitis C virus (HCV) infection has been hampered by appearance of toxicity during clinical trials that evaded detection during preclinical studies. It is well established that the human mitochondrial DNA polymerase is an off target for deoxyribonucleoside reverse transcriptase inhibitors. Here we test the hypothesis that triphosphorylated metabolites of therapeutic ribonucleoside analogues are substrates for cellular RNA polymerases. We have used ribonucleoside analogues with activity against HCV as model compounds for therapeutic ribonucleosides. We have included ribonucleoside analogues containing 2′-C-methyl, 4′-methyl and 4′-azido substituents that are non-obligate chain terminators of the HCV RNA polymerase. We show that all of the anti-HCV ribonucleoside analogues are substrates for human mitochondrial RNA polymerase (POLRMT) and eukaryotic core RNA polymerase II (Pol II) in vitro. Unexpectedly, analogues containing 2′-C-methyl, 4′-methyl and 4′-azido substituents were inhibitors of POLRMT and Pol II. Importantly, the proofreading activity of TFIIS was capable of excising these analogues from Pol II transcripts. Evaluation of transcription in cells confirmed sensitivity of POLRMT to antiviral ribonucleosides, while Pol II remained predominantly refractory. We introduce a parameter termed the mitovir (mitochondrial dysfunction caused by antiviral ribonucleoside) score that can be readily obtained during preclinical studies that quantifies the mitochondrial toxicity potential of compounds. We suggest the possibility that patients exhibiting adverse effects during clinical trials may be more susceptible to damage by nucleoside analogs because of defects in mitochondrial or nuclear transcription. The paradigm reported here should facilitate development of ribonucleosides with a lower potential for toxicity. Ribonucleoside analogues have potential utility as anti-viral, -parasitic, -bacterial and -cancer agents. However, their clinical applications have been limited by side effects of unknown origin. Here we show in biochemical and cell-based studies that antiviral ribonucleotide analogues are substrates for human mitochondrial RNA polymerase (POLRMT) and eukaryotic core RNA polymerase II (Pol II) in vitro. Analogues that terminate RNA synthesis by viral RNA polymerases also inhibit these cellular RNA polymerase. Importantly, the TFIIS proofreading activity of Pol II is capable of excising these analogues from Pol II transcripts. We introduce a parameter termed the mitovir (mitochondrial dysfunction caused by antiviral ribonucleoside) score that can be readily obtained during preclinical studies that quantifies the mitochondrial toxicity potential of compounds. We suggest the possibility that patients exhibiting adverse effects during clinical trials may be more susceptible to damage by nucleoside analogs because of defects in mitochondrial or nuclear transcription. The paradigm reported here should facilitate development of ribonucleosides with a lower potential for toxicity.
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Affiliation(s)
- Jamie J. Arnold
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- * E-mail: (JJA); (CEC)
| | - Suresh D. Sharma
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Joy Y. Feng
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Adrian S. Ray
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Eric D. Smidansky
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Maria L. Kireeva
- Frederick National Laboratory for Cancer Research, NCI, Frederick, Maryland, United States of America
| | - Aesop Cho
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Jason Perry
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Jennifer E. Vela
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Yeojin Park
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Yili Xu
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Yang Tian
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Darius Babusis
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Ona Barauskus
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Blake R. Peterson
- Department of Medicinal Chemistry, The University of Kansas, Lawrence, Kansas, United States of America
| | - Averell Gnatt
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Mikhail Kashlev
- Frederick National Laboratory for Cancer Research, NCI, Frederick, Maryland, United States of America
| | - Weidong Zhong
- Gilead Sciences, Inc., Foster City, California, United States of America
| | - Craig E. Cameron
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- * E-mail: (JJA); (CEC)
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Franzolin E, Miazzi C, Frangini M, Palumbo E, Rampazzo C, Bianchi V. The pyrimidine nucleotide carrier PNC1 and mitochondrial trafficking of thymidine phosphates in cultured human cells. Exp Cell Res 2012; 318:2226-36. [PMID: 22677043 DOI: 10.1016/j.yexcr.2012.05.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 05/26/2012] [Accepted: 05/28/2012] [Indexed: 10/28/2022]
Abstract
In cycling cells cytosolic de novo synthesis of deoxynucleotides is the main source of precursors for mitochondrial (mt) DNA synthesis. The transfer of deoxynucleotides across the inner mt membrane requires protein carriers. PNC1, a SLC25 family member, exchanges pyrimidine nucleoside triphosphates in liposomes and its downregulation decreases mtUTP concentration in cultured cells. By an isotope-flow protocol we confirmed transport of uridine nucleotides by PNC1 in intact cultured cells and investigated PNC1 involvement in the mt trafficking of thymidine phosphates. Key features of our approach were the manipulation of PNC1 expression by RNA interference or inducible overexpression, the employment of cells proficient or deficient for cytosolic thymidine kinase (TK1) to distinguish the direction of flow of thymidine nucleotides across the mt membrane during short pulses with [(3)H]-thymidine, the determination of mtdTTP specific radioactivity to quantitate the rate of mtdTTP export to the cytoplasm. Downregulation of PNC1 in TK1(-) cells increased labeled dTTP in mitochondria due to a reduced rate of export. Overexpression of PNC1 in TK1(+) cells increased mtdTTP pool size and radioactivity, suggesting an involvement in the import of thymidine phosphates. Thus PNC1 is a component of the network regulating the mtdTTP pool in human cells.
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Affiliation(s)
- Elisa Franzolin
- Department of Biology, University of Padova, Via Ugo Bassi 58B, I-35131 Padova, Italy
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44
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Arnold JJ, Smidansky ED, Moustafa IM, Cameron CE. Human mitochondrial RNA polymerase: structure-function, mechanism and inhibition. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2012; 1819:948-60. [PMID: 22551784 DOI: 10.1016/j.bbagrm.2012.04.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 04/09/2012] [Accepted: 04/11/2012] [Indexed: 11/29/2022]
Abstract
Transcription of the human mitochondrial genome is required for the expression of 13 subunits of the respiratory chain complexes involved in oxidative phosphorylation, which is responsible for meeting the cells' energy demands in the form of ATP. Also transcribed are the two rRNAs and 22 tRNAs required for mitochondrial translation. This process is accomplished, with the help of several accessory proteins, by the human mitochondrial RNA polymerase (POLRMT, also known as h-mtRNAP), a nuclear-encoded single-subunit DNA-dependent RNA polymerase (DdRp or RNAP) that is distantly related to the bacteriophage T7 class of single-subunit RNAPs. In addition to its role in transcription, POLRMT serves as the primase for mitochondrial DNA replication. Therefore, this enzyme is of fundamental importance for both expression and replication of the human mitochondrial genome. Over the past several years rapid progress has occurred in understanding POLRMT and elucidating the molecular mechanisms of mitochondrial transcription. Important accomplishments include development of recombinant systems that reconstitute human mitochondrial transcription in vitro, determination of the X-ray crystal structure of POLRMT, identification of distinct mechanisms for promoter recognition and transcription initiation, elucidation of the kinetic mechanism for POLRMT-catalyzed nucleotide incorporation and discovery of unique mechanisms of mitochondrial transcription inhibition including the realization that POLRMT is an off target for antiviral ribonucleoside analogs. This review summarizes the current understanding of POLRMT structure-function, mechanism and inhibition. This article is part of a Special Issue entitled: Mitochondrial Gene Expression.
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Affiliation(s)
- Jamie J Arnold
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA.
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Koczor CA, Torres RA, Lewis W. The role of transporters in the toxicity of nucleoside and nucleotide analogs. Expert Opin Drug Metab Toxicol 2012; 8:665-76. [PMID: 22509856 DOI: 10.1517/17425255.2012.680885] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Two families of nucleoside analogs have been developed to treat viral infections and cancer, but these compounds can cause tissue- and cell-specific toxicity related to their uptake and subcellular activity, which are dictated by host enzymes and transporters. Cellular uptake of these compounds requires nucleoside transporters that share functional similarities but differ in substrate specificity. Tissue-specific cellular expression of these transporters enables nucleoside analogs to produce their tissue-specific toxic effects, a limiting factor in the treatment of retroviruses and cancer. AREAS COVERED This review discusses the families of nucleoside transporters and how they mediate cellular uptake of nucleoside analogs. Specific focus is placed on examples of known cases of transporter-mediated cellular toxicity and classification of the toxicities resulting. Efflux transporters are also explored as a contributor to analog toxicity and cell-specific effects. EXPERT OPINION Efforts to modulate transporter uptake/clearance remain long-term goals of oncologists and virologists. Accordingly, subcellular approaches that either increase or decrease intracellular nucleoside analog concentrations are eagerly sought and include transporter inhibitors and targeting transporter expression. However, additional understanding of nucleoside transporter kinetics, tissue expression and genetic polymorphisms is required to design better molecules and better therapies.
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46
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Leung GPH. Iatrogenic mitochondriopathies: a recent lesson from nucleoside/nucleotide reverse transcriptase inhibitors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 942:347-69. [PMID: 22399431 DOI: 10.1007/978-94-007-2869-1_16] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The use of nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) has revolutionized the treatment of infection by human immunodeficiency virus (HIV) and hepatitis-B virus. NRTIs can suppress viral replication in the long-term, but possess significant toxicity that can seriously compromise treatment effectiveness. The major toxicity of NRTIs is mitochondrial toxicity. This manifests as serious side effects such as myopathy, peripheral neuropathy and lactic acidosis. In general, it is believed that the mitochondrial pathogenesis is closely related to the effect of NRTIs on mitochondrial DNA polymerase-γ. Depletion and mutation of mitochondrial DNA during chronic NRTI therapy may lead to cellular respiratory dysfunction and release of reactive oxidative species, resulting in cellular damage. It is now apparent that the etiology is far more complex than originally thought. It appears to involve multiple mechanisms as well as host factors such as HIV per se, inborn mitochondrial mutation, and sex. Management of mitochondrial toxicity during NRTI therapy remains a challenge. Interruption of NRTI therapy and substitution of the causative agents with alternative better-tolerated NRTIs represents the mainstay of management for mitochondrial toxicity and its clinical manifestations. A range of pharmacological approaches has been proposed as treatments and prophylaxes.
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Affiliation(s)
- George P H Leung
- Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China.
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Minuesa G, Huber-Ruano I, Pastor-Anglada M, Koepsell H, Clotet B, Martinez-Picado J. Drug uptake transporters in antiretroviral therapy. Pharmacol Ther 2011; 132:268-79. [DOI: 10.1016/j.pharmthera.2011.06.007] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Accepted: 06/30/2011] [Indexed: 01/11/2023]
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48
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Okayama T, Yoshisue K, Kuwata K, Komuro M, Ohta S, Nagayama S. Involvement of Concentrative Nucleoside Transporter 1 in Intestinal Absorption of Trifluorothymidine, a Novel Antitumor Nucleoside, in Rats. J Pharmacol Exp Ther 2011; 340:457-62. [DOI: 10.1124/jpet.111.186296] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Abstract
BACKGROUND Nucleoside/nucleobase transporters have been investigated since the 1960s. In particular, equilibrative nucleoside transporters were thought to be valuable drug targets, since they are involved in various kinds of viral and parasitic diseases as well as cancers. DISCUSSION In the postgenomic era multiple transporters, including different subtypes, have been cloned and characterized on the molecular level. In this article we summarize recent advances regarding structure, function and localization of nucleoside/nucleobase transporters as well as the pharmacological profile of selected drugs. CONCLUSION Knowledge of the different kinetic properties and structural features of nucleoside transporters can either be used for the rational design of therapeutics directly targeting the transporter itself or for the delivery of drugs using the transporter as a port of entry into the target cell. Equilibrative nucleoside transporters are of considerable pharmacological interest as drug targets for the development of drugs tailored to each patient's need for the treatment of cardiac disease, cancer and viral infections.
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Amacher DE. The mechanistic basis for the induction of hepatic steatosis by xenobiotics. Expert Opin Drug Metab Toxicol 2011; 7:949-65. [PMID: 21510823 DOI: 10.1517/17425255.2011.577740] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Hepatic steatosis is the histological observation of numerous lipid inclusions due to an excess accumulation of triacylglycerols. They are a concern with new therapeutic candidates because they signify altered lipid metabolism that can progress to more serious liver toxicity. AREAS COVERED This article is based on an article search using the PubMed database from 1987 to 2011 and confirms associations for several previously marketed drugs with four basic hepatocellular mechanisms. The article also describes how these mechanisms are controlled by master regulators of lipid metabolism, which include gene transcription factors, nuclear receptors, hormonal signaling, energy sensing proteins, endoplasmic reticulum stress signaling and certain key metabolic intermediates. EXPERT OPINION Drug-induced hepatic steatosis is typically not detectable by conventional means other than invasive histological examinations. By understanding the basic mechanisms, key regulators and energy signaling systems of the liver, the investigator is better equipped to avoid xenobiotics with steatogenic potential in the drug discovery or early development process. There are now a number of methods for detecting this potential, specifically gene expression or metabolomic profiling and pathway analysis or mechanism-based in vitro systems.
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