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Prodrug Therapies for Infectious and Neurodegenerative Diseases. Pharmaceutics 2022; 14:pharmaceutics14030518. [PMID: 35335894 PMCID: PMC8953076 DOI: 10.3390/pharmaceutics14030518] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/17/2022] [Accepted: 02/22/2022] [Indexed: 02/06/2023] Open
Abstract
Prodrugs are bioreversible drug derivatives which are metabolized into a pharmacologically active drug following chemical or enzymatic modification. This approach is designed to overcome several obstacles that are faced by the parent drug in physiological conditions that include rapid drug metabolism, poor solubility, permeability, and suboptimal pharmacokinetic and pharmacodynamic profiles. These suboptimal physicochemical features can lead to rapid drug elimination, systemic toxicities, and limited drug-targeting to disease-affected tissue. Improving upon these properties can be accomplished by a prodrug design that includes the careful choosing of the promoiety, the linker, the prodrug synthesis, and targeting decorations. We now provide an overview of recent developments and applications of prodrugs for treating neurodegenerative, inflammatory, and infectious diseases. Disease interplay reflects that microbial infections and consequent inflammation affects neurodegenerative diseases and vice versa, independent of aging. Given the high prevalence, personal, social, and economic burden of both infectious and neurodegenerative disorders, therapeutic improvements are immediately needed. Prodrugs are an important, and might be said a critical tool, in providing an avenue for effective drug therapy.
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2
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Dezani TM, Dezani AB, Serra CHDR. Development and validation of RP-HPLC method for simultaneous determination of lamivudine, stavudine, and zidovudine in perfusate samples: Application to the Single-Pass Intestinal Perfusion (SPIP) studies. BRAZ J PHARM SCI 2021. [DOI: 10.1590/s2175-97902020000419073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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3
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Nguyen K, Kubota M, Arco JD, Feng C, Singha M, Beasley S, Sakr J, Gandhi SP, Blurton-Jones M, Fernández Lucas J, Spitale RC. A Bump-Hole Strategy for Increased Stringency of Cell-Specific Metabolic Labeling of RNA. ACS Chem Biol 2020; 15:3099-3105. [PMID: 33222436 DOI: 10.1021/acschembio.0c00755] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Profiling RNA expression in a cell-specific manner continues to be a grand challenge in biochemical research. Bioorthogonal nucleosides can be utilized to track RNA expression; however, these methods currently have limitations due to background and incorporation of analogs into undesired cells. Herein, we design and demonstrate that uracil phosphoribosyltransferase can be engineered to match 5-vinyluracil for cell-specific metabolic labeling of RNA with exceptional specificity and stringency.
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Affiliation(s)
- Kim Nguyen
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697, United States
| | - Miles Kubota
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697, United States
| | - Jon del Arco
- Universidad Europea de Madrid, E-28670 Villaviciosa de Odon, Madrid Spain
| | - Chao Feng
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697, United States
| | - Monika Singha
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697, United States
| | - Samantha Beasley
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697, United States
| | - Jasmine Sakr
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697, United States
| | - Sunil P. Gandhi
- Neurobiology and Behavior, University of California, Irvine, Irvine, California 92697, United States
| | - Matthew Blurton-Jones
- Neurobiology and Behavior, University of California, Irvine, Irvine, California 92697, United States
| | - Jesus Fernández Lucas
- Universidad Europea de Madrid, E-28670 Villaviciosa de Odon, Madrid Spain
- Grupo de Investigación en Ciencias Naturales y Exactas, GICNEX, Universidad de la Costa, CUC, Barranquilla, Colombia
| | - Robert C. Spitale
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697, United States
- Department of Chemistry, University of California, Irvine. Irvine, California 92697, United States
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, California 92697, United States
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Sun Y, Ke Y, Li C, Wang J, Tu L, Hu L, Jin Y, Chen H, Gong J, Yu Z. Bifunctional and Unusual Amino Acid β- or γ-Ester Prodrugs of Nucleoside Analogues for Improved Affinity to ATB0,+ and Enhanced Metabolic Stability: An Application to Floxuridine. J Med Chem 2020; 63:10816-10828. [DOI: 10.1021/acs.jmedchem.0c00149] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Yongbing Sun
- Division of Pharmaceutics, Jiangxi University of Traditional Chinese Medicine, No. 1688 Meiling Road, Nanchang 330004, China
| | - Yu Ke
- Division of Pharmaceutics, Jiangxi University of Traditional Chinese Medicine, No. 1688 Meiling Road, Nanchang 330004, China
| | - Chunshi Li
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang 110016, China
| | - Jian Wang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, No. 103 Wenhua Road, Shenyang 110016, China
| | - Liangxing Tu
- Division of Pharmaceutics, Jiangxi University of Traditional Chinese Medicine, No. 1688 Meiling Road, Nanchang 330004, China
| | - Lvjiang Hu
- Division of Pharmaceutics, Jiangxi University of Traditional Chinese Medicine, No. 1688 Meiling Road, Nanchang 330004, China
| | - Yi Jin
- Division of Pharmaceutics, Jiangxi University of Traditional Chinese Medicine, No. 1688 Meiling Road, Nanchang 330004, China
| | - Hao Chen
- Division of Pharmaceutics, Jiangxi University of Traditional Chinese Medicine, No. 1688 Meiling Road, Nanchang 330004, China
| | - Jianping Gong
- Division of Pharmaceutics, Jiangxi University of Traditional Chinese Medicine, No. 1688 Meiling Road, Nanchang 330004, China
| | - Zhiqiang Yu
- School of Pharmaceutical Sciences, Southern Medical University, No. 1023, Shatai South Road, Guangzhou 510515, China
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Halling Folkmar Andersen A, Tolstrup M. The Potential of Long-Acting, Tissue-Targeted Synthetic Nanotherapy for Delivery of Antiviral Therapy Against HIV Infection. Viruses 2020; 12:E412. [PMID: 32272815 PMCID: PMC7232358 DOI: 10.3390/v12040412] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 03/30/2020] [Accepted: 04/01/2020] [Indexed: 12/18/2022] Open
Abstract
Oral administration of a combination of two or three antiretroviral drugs (cART) has transformed HIV from a life-threatening disease to a manageable infection. However, as the discontinuation of therapy leads to virus rebound in plasma within weeks, it is evident that, despite daily pill intake, the treatment is unable to clear the infection from the body. Furthermore, as cART drugs exhibit a much lower concentration in key HIV residual tissues, such as the brain and lymph nodes, there is a rationale for the development of drugs with enhanced tissue penetration. In addition, the treatment, with combinations of multiple different antiviral drugs that display different pharmacokinetic profiles, requires a strict dosing regimen to avoid the emergence of drug-resistant viral strains. An intriguing opportunity lies within the development of long-acting, synthetic scaffolds for delivering cART. These scaffolds can be designed with the goal to reduce the frequency of dosing and furthermore, hold the possibility of potential targeting to key HIV residual sites. Moreover, the synthesis of combinations of therapy as one molecule could unify the pharmacokinetic profiles of different antiviral drugs, thereby eliminating the consequences of sub-therapeutic concentrations. This review discusses the recent progress in the development of long-acting and tissue-targeted therapies against HIV for the delivery of direct antivirals, and examines how such developments fit in the context of exploring HIV cure strategies.
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Affiliation(s)
- Anna Halling Folkmar Andersen
- Department of Infectious Diseases, Aarhus University Hospital, 8200 Aarhus, Denmark;
- Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark
| | - Martin Tolstrup
- Department of Infectious Diseases, Aarhus University Hospital, 8200 Aarhus, Denmark;
- Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark
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Understanding of human ATP binding cassette superfamily and novel multidrug resistance modulators to overcome MDR. Biomed Pharmacother 2018; 100:335-348. [PMID: 29453043 DOI: 10.1016/j.biopha.2018.02.038] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/08/2018] [Accepted: 02/09/2018] [Indexed: 01/27/2023] Open
Abstract
Indeed, multi-drug resistance (MDR) is a significant obstacle to effective chemotherapy. The overexpression of ATP-binding cassette (ABC) membrane transporters is a principal cause of enhanced cytotoxic drug efflux and treatment failure in various types of cancers. At cellular level, the pumps of ABC family regulate the transportation of numerous substances including drugs in and out of the cells. In past, the overexpression of ABC pumps suggested a well-known mechanism of drug resistance in cancers as well as infectious diseases. In oncology, the search for new compounds for the inhibition of these hyperactive ABC pumps either genetically or functionally, growing interest to reverse multi-drug resistance and increase chemotherapeutic effects. Several ABC pump inhibitor/modulators has been explored to address the cancer associated MDR. However, the clinical results are still disappointing and conventional chemotherapies are constantly failed in successful eradication of MDR tumors. In this context, the structural and functional understanding of different ATP pumps is most important. In this concise review, we elaborated basic crystal structure of ABC transporter proteins as well as its critical elements such as different domains, motifs as well as some important amino acids which are responsible for ATP binding and drug efflux as well as demonstrated an ATP-switch model employed by various ABC membrane transporters. Furthermore, we briefly summarized different newly identified MDR inhibitors/modulators, deployed alone or in combination with cytotoxic agents to deal with MDR in different types of cancers.
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Slusarczyk M, Serpi M, Pertusati F. Phosphoramidates and phosphonamidates (ProTides) with antiviral activity. Antivir Chem Chemother 2018; 26:2040206618775243. [PMID: 29792071 PMCID: PMC5971382 DOI: 10.1177/2040206618775243] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 04/09/2018] [Indexed: 12/15/2022] Open
Abstract
Following the first report on the nucleoside phosphoramidate (ProTide) prodrug approach in 1990 by Chris McGuigan, the extensive investigation of ProTide technology has begun in many laboratories. Designed with aim to overcome limitations and the key resistance mechanisms associated with nucleoside analogues used in the clinic (poor cellular uptake, poor conversion to the 5'-monophosphate form), the ProTide approach has been successfully applied to a vast number of nucleoside analogues with antiviral and anticancer activity. ProTides consist of a 5'-nucleoside monophosphate in which the two hydroxyl groups are masked with an amino acid ester and an aryloxy component which once in the cell is enzymatically metabolized to deliver free 5'-monophosphate, which is further transformed to the active 5'-triphosphate form of the nucleoside analogue. In this review, the seminal contribution of Chris McGuigan's research to this field is presented. His technology proved to be extremely successful in drug discovery and has led to two Food and Drug Administration-approved antiviral agents.
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Affiliation(s)
| | - Michaela Serpi
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, UK
| | - Fabrizio Pertusati
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, UK
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Murakami T. A Minireview: Usefulness of Transporter-Targeted Prodrugs in Enhancing Membrane Permeability. J Pharm Sci 2016; 105:2515-2526. [DOI: 10.1016/j.xphs.2016.05.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 04/28/2016] [Accepted: 05/03/2016] [Indexed: 11/26/2022]
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Dezani TM, Dezani AB, Junior JBDS, Serra CHDR. Single-Pass Intestinal Perfusion (SPIP) and prediction of fraction absorbed and permeability in humans: A study with antiretroviral drugs. Eur J Pharm Biopharm 2016; 104:131-9. [PMID: 27130787 DOI: 10.1016/j.ejpb.2016.04.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 03/17/2016] [Accepted: 04/24/2016] [Indexed: 10/21/2022]
Abstract
In recent years, the prediction of oral drug absorption in humans has been a challenge for researchers and many techniques for permeability studies have been developed for several purposes, including biowaiver processes. The Single-Pass Intestinal Perfusion (SPIP) method performed in rats can provide permeability results closest to in vivo condition. The purpose of the present study was to evaluate the intestinal permeability of the antiretroviral drugs lamivudine, stavudine and zidovudine using the SPIP method in rats and to predict their permeability (Peff,humans) and fraction absorbed (Fa) in humans. Metoprolol and fluorescein were used as marker compounds of high and low permeability, respectively. The effective permeability (Peff) results showed that stavudine and zidovudine have high permeability characteristics while lamivudine presented the lowest result. From Peff values obtained in rats, the Peff,humans and Fa were calculated. The use of SPIP in rats and calculations for absorption prediction in humans may indicate the transport mechanisms and/or pre-systemic metabolism involved on permeation processes of drugs, since this model is the closest to in vivo conditions.
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Affiliation(s)
- Thaisa Marinho Dezani
- Department of Pharmacy, Faculty of Pharmaceutical Sciences of the University of São Paulo, Avenida Professor Lineu Prestes, 580, Bl. 13, 05508-900 São Paulo, SP, Brazil
| | - André Bersani Dezani
- Department of Pharmacy, Faculty of Pharmaceutical Sciences of the University of São Paulo, Avenida Professor Lineu Prestes, 580, Bl. 13, 05508-900 São Paulo, SP, Brazil
| | - João Batista da Silva Junior
- Department of Pharmacy, Faculty of Pharmaceutical Sciences of the University of São Paulo, Avenida Professor Lineu Prestes, 580, Bl. 13, 05508-900 São Paulo, SP, Brazil
| | - Cristina Helena Dos Reis Serra
- Department of Pharmacy, Faculty of Pharmaceutical Sciences of the University of São Paulo, Avenida Professor Lineu Prestes, 580, Bl. 13, 05508-900 São Paulo, SP, Brazil.
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Alexander P, Kucera G, Pardee TS. Improving nucleoside analogs via lipid conjugation: Is fatter any better? Crit Rev Oncol Hematol 2016; 100:46-56. [PMID: 26829896 DOI: 10.1016/j.critrevonc.2016.01.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 12/22/2015] [Accepted: 01/16/2016] [Indexed: 10/22/2022] Open
Abstract
In the past few decades, nucleoside analog drugs have been used to treat a large variety of cancers. These anti-metabolite drugs mimic nucleosides and interfere with chain lengthening upon incorporation into the DNA or RNA of actively replicating cells. However, efficient delivery of these drugs is limited due to their pharmacokinetic properties, and tumors often develop drug resistance. In addition, nucleoside analogs are generally hydrophilic, resulting in poor bioavailability and impaired blood-brain barrier penetration. Conjugating these drugs to lipids modifies their pharmacokinetic properties and may improve in vivo efficacy. This review will cover recent advances in the field of conjugation of phospholipids to nucleoside analogs. This includes conjugation of myristic acid, 12-thioethyldodecanoic acid, 5-elaidic acid esters, phosphoramidate, and self-emulsifying formulations. Relevant in vitro and in vivo data will be discussed for each drug, as well as any available data from clinical trials.
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Affiliation(s)
- Peter Alexander
- Cancer Biology, Comprehensive Cancer Center of Wake Forest University, Winston-Salem, NC, United States
| | - Gregory Kucera
- Internal Medicine, Wake Forest Baptist Health, Winston-Salem, NC, United States; Cancer Biology, Comprehensive Cancer Center of Wake Forest University, Winston-Salem, NC, United States
| | - Timothy S Pardee
- Internal Medicine, Wake Forest Baptist Health, Winston-Salem, NC, United States; Cancer Biology, Comprehensive Cancer Center of Wake Forest University, Winston-Salem, NC, United States.
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Liu JA, Guo XP, Liang S, An F, Shen HY, Xu YJ. Regioselective synthesis of 5′-amino acid esters of some nucleosides via orthogonal protecting protocol. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.01.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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12
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Ferreira da Silva C, Severino P, Martins F, Santana MHA, Souto EB. Didanosine-loaded chitosan microspheres optimized by surface-response methodology: a modified "Maximum Likelihood Classification" approach formulation for reverse transcriptase inhibitors. Biomed Pharmacother 2015; 70:46-52. [PMID: 25776478 DOI: 10.1016/j.biopha.2014.12.047] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 12/30/2014] [Indexed: 12/13/2022] Open
Abstract
Didanosine-loaded chitosan microspheres were developed applying a surface-response methodology and using a modified Maximum Likelihood Classification. The operational conditions were optimized with the aim of maintaining the active form of didanosine (ddI), which is sensitive to acid pH, and to develop a modified and mucoadhesive formulation. The loading of the drug within the chitosan microspheres was carried out by ionotropic gelation technique with sodium tripolyphosphate (TPP) as cross-linking agent and magnesium hydroxide (Mg(OH)₂) to assure the stability of ddI. The optimization conditions were set using a surface-response methodology and applying the "Maximum Likelihood Classification", where the initial chitosan concentration, TPP and ddI concentration were set as the independent variables. The maximum ddI-loaded in microspheres (i.e. 1433 mg of ddI/g chitosan), was obtained with 2% (w/v) chitosan and 10% TPP. The microspheres depicted an average diameter of 11.42 μm and ddI was gradually released during 2 h in simulated enteric fluid.
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Affiliation(s)
- Classius Ferreira da Silva
- Departamento de Ciências Exatas e da Terra, Universidade Federal de São Paulo, Rua Arthur Riedel, 275, Diadema 09972-270, Brazil
| | - Patrícia Severino
- Department of Biotechnological Processes, School of Engineering Chemical, University of Campinas, Campinas 13083-970, Brazil; University of Tiradentes and Institute of Technology and Research, Av. Murilo Dantas 300, 49010-390 Aracaju, Brazil
| | - Fernanda Martins
- Department of Biotechnological Processes, School of Engineering Chemical, University of Campinas, Campinas 13083-970, Brazil
| | - Maria Helena A Santana
- Department of Biotechnological Processes, School of Engineering Chemical, University of Campinas, Campinas 13083-970, Brazil.
| | - Eliana B Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; Center for Neuroscience and Cell Biology & Institute for Biomedical Imaging and Life Sciences (CNC-IBILI), University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal.
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Estimation of intracellular concentration of stavudine triphosphate in HIV-infected children given a reduced dose of 0.5 milligrams per kilogram twice daily. Antimicrob Agents Chemother 2013; 58:1084-91. [PMID: 24295968 DOI: 10.1128/aac.01717-13] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The antiviral efficacy of stavudine depends on the trough concentration of its intracellular metabolite, stavudine-triphosphate (d4T-TP), while the degree of stavudine's mitochondrial toxicity depends on its peak concentration. Rates of mitochondrial toxicity are high when stavudine is used at the current standard pediatric dose (1 mg/kg twice daily [BID]). Evidence from adult work suggests that half of the original standard adult dose (i.e., 20 mg BID) may be equally effective, with markedly less mitochondrial toxicity. We present a population pharmacokinetic model to predict intracellular d4T-TP concentrations in pediatric HIV-infected patients administered a dose of 0.5 mg/kg BID. Our model predicted that the reduced pediatric dose would result in a trough intracellular d4T-TP concentration above that of the reduced 20-mg adult dose and a peak concentration below that of the 20-mg adult dose. The simulated pediatric intracellular d4T-TP at 0.5 mg/kg BID resulted in median peak and trough values of approximately 23.9 fmol/10(6) cells (95% prediction interval [PI], 14.2 to 41 fmol/10(6) cells) and 14.8 fmol/10(6) cells (95% PI, 7.2 to 31 fmol/10(6) cells), respectively. The peak and trough concentrations resulting from a 20-mg BID adult dose were 28.4 fmol/10(6) cells (95% PI, 17.3 to 45.5 fmol/10(6) cells) and 13 fmol/10(6) cells (95% PI, 6.8 to 28.6 fmol/10(6) cells), respectively. Halving the current standard pediatric dose should therefore not compromise antiviral efficacy, while markedly reducing mitochondrial toxicity.
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Wang C, Lin W, Playa H, Sun S, Cameron K, Buolamwini J. Dipyridamole analogs as pharmacological inhibitors of equilibrative nucleoside transporters. Identification of novel potent and selective inhibitors of the adenosine transporter function of human equilibrative nucleoside transporter 4 (hENT4). Biochem Pharmacol 2013; 86:1531-40. [PMID: 24021350 PMCID: PMC3866046 DOI: 10.1016/j.bcp.2013.08.063] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 08/27/2013] [Accepted: 08/27/2013] [Indexed: 01/04/2023]
Abstract
To identify needed human equilibrative nucleoside transporter 4 (hENT4) inhibitors, we cloned and stably expressed the recombinant protein in PK15NTD (nucleoside transporter deficient) cells, and, investigated its interaction with a series of dipyridamole analogs synthesized in our laboratory. Compounds were tested in this newly established hENT4 expressing system as well in previous stably expressed hENT1 and hENT2 expressing systems. Of the dipyridamole analogs evaluated, about one fourth of the compounds inhibited hENT4 with higher potencies than dipyridamole. The most potent of them, Compound 30 displayed an IC₅₀ of 74.4 nM, making it about 38 times more potent than dipyridamole (IC₅₀=2.8 μM), and selectivities of about 80-fold and 20-fold relative to ENT1 and ENT2, respectively. Structure-activity relationship showed nitrogen-containing monocyclic rings and noncyclic substituents at the 4- and 8-positions of the pyrimido[5,4-d]pyrimidine were important for the inhibitory activity against hENT4. The most potent and selective hENT4 inhibitors tended to have a 2,6-di(N-monohydroxyethyl) substitution on the pyrimidopyrimidine ring system. The inhibitors of hENT4 identified in this study are the most selective and potent inhibitors of hENT4 adenosine transporter function to date, and should serve as useful pharmacological/biochemical tools and/or potential leads for ENT4-based therapeutics. Also, the new hENT4-expressing PK15 cell line established will serve as a useful screening tool for the discovery and design of hENT4 ligands.
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Affiliation(s)
- Chunmei Wang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | | | - Hilaire Playa
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | - Shan Sun
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | - Kenyuna Cameron
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | - John Buolamwini
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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Sosnik A. Reversal of multidrug resistance by the inhibition of ATP-binding cassette pumps employing "Generally Recognized As Safe" (GRAS) nanopharmaceuticals: A review. Adv Drug Deliv Rev 2013; 65:1828-51. [PMID: 24055628 DOI: 10.1016/j.addr.2013.09.002] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 09/06/2013] [Accepted: 09/10/2013] [Indexed: 12/17/2022]
Abstract
Pumps of the ATP-binding cassette superfamily (ABCs) regulate the access of drugs to the intracellular space. In this context, the overexpression of ABCs is a well-known mechanism of multidrug resistance (MDR) in cancer and infectious diseases (e.g., viral hepatitis and the human immunodeficiency virus) and is associated with therapeutic failure. Since their discovery, ABCs have emerged as attractive therapeutic targets and the search of compounds that inhibit their genetic expression and/or their functional activity has gained growing interest. Different generations of pharmacological ABC inhibitors have been explored over the last four decades to address resistance in cancer, though clinical results have been somehow disappointing. "Generally Recognized As Safe" (GRAS) is a U.S. Food and Drug Administration designation for substances that are accepted as safe for addition in food. Far from being "inert", some amphiphilic excipients used in the production of pharmaceutical products have been shown to inhibit the activity of ABCs in MDR tumors, emerging as a clinically translatable approach to overcome resistance. The present article initially overviews the classification, structure and function of the different ABCs, with emphasis on those pumps related to drug resistance. Then, the different attempts to capitalize on the activity of GRAS nanopharmaceuticals as ABC inhibitors are discussed.
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Affiliation(s)
- Alejandro Sosnik
- The Group of Biomaterials and Nanotechnology for Improved Medicines (BIONIMED), Department of Pharmaceutical Technology, Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Argentina; National Science Research Council (CONICET), Argentina; Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel.
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Chiappetta DA, Hocht C, Opezzo JAW, Sosnik A. Intranasal administration of antiretroviral-loaded micelles for anatomical targeting to the brain in HIV. Nanomedicine (Lond) 2012; 8:223-37. [PMID: 23173734 DOI: 10.2217/nnm.12.104] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
AIM To investigate the intranasal administration of poly(ethylene oxide)-poly(propylene oxide) polymeric micelles loaded with high payloads of the first-line antiretroviral drug efavirenz for targeting to the CNS. METHODS & MATERIALS The effect of micellar size and composition and drug payload was assessed, employing simple micelles made of a highly hydrophilic copolymer, poloxamer F127, loaded with 20 mg/ml drug and mixed micelles containing 75% of a poloxamine of intermediate hydrophobicity, T904, and 25% F127 loaded with 20 and 30 mg/ml drug. F127 confers high physical stability, while T904 substantially improves the encapsulation capacity of the micelles. RESULTS The bioavailability of the drug in the CNS was increased fourfold and the relative exposure index (ratio between the area under the curve in the CNS and plasma) was increased fivefold with respect to the same system administered intravenously. CONCLUSION These findings demonstrate the potential of this scalable and cost-viable strategy to address the HIV sanctuary in the CNS.
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Affiliation(s)
- Diego A Chiappetta
- The Group of Biomaterials & Nanotechnology for Improved Medicines (BIONIMED), Department of Pharmaceutical Technology, Faculty of Pharmacy & Biochemistry, University of Buenos Aires, 956 Junín St, 6th Floor, Buenos Aires CP1113, Argentina
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Seremeta KP, Chiappetta DA, Sosnik A. Poly(ε-caprolactone), Eudragit® RS 100 and poly(ε-caprolactone)/Eudragit® RS 100 blend submicron particles for the sustained release of the antiretroviral efavirenz. Colloids Surf B Biointerfaces 2012; 102:441-9. [PMID: 23010128 DOI: 10.1016/j.colsurfb.2012.06.038] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 06/12/2012] [Accepted: 06/24/2012] [Indexed: 10/28/2022]
Abstract
The design of simple and scalable drug delivery systems to target the central nervous system (CNS) could represent a breakthrough in the addressment of the HIV-associated neuropathogenesis. The intranasal (i.n.) route represents a minimally invasive strategy to surpass the blood-brain barrier, though it demands the use of appropriate nanocarriers bearing high drug payloads and displaying sufficiently long residence time. The present work explored the development of submicron particles made of poly(ε-caprolactone) (PCL), Eudragit(®) RS 100 (RS a copolymer of ethylacrylate, methylmethacrylate and methacrylic acid esterified with quaternary ammonium groups) and their blends, loaded with the first-choice antiretroviral efavirenz (EFV) as an approach to fine tune the particle size and the release kinetics. Particles displaying hydrodynamic diameters between 90 and 530 nm were obtained by two methods: nanoprecipitation and emulsion/solvent diffusion/evaporation. In general, the former resulted in smaller particles and narrower size distributions. The encapsulation efficiency was greater than 94%, the drug weight content approximately 10% and the yield in the 72.5-90.0% range. The highly positive surface (>+30 mV) rendered the suspensions physically stable for more than one month. In vitro release assays indicated that the incorporation of the poly(methacrylate) into the composition reduced the burst effect and slowed the release rate down with respect to pure poly(ε-caprolactone) particles. The analysis of the release profile indicated that, in all cases, the kinetics adjusted well to the Higuchi model with R(adj)(2) values >0.9779. These findings suggested that the release was mainly controlled by diffusion. In addition, when data were analyzed by the Korsmeyer-Peppas model, n values were in the 0.520-0.587 range, indicating that the drug release was accomplished by the combination of two phenomena: diffusion and polymer chain relaxation. Based on ATR/FT-IR analysis that investigated drug/polymer matrix interactions, the potential role of the hydrophobic interactions of C-F groups of EFV with carbonyl groups in the backbone of PCL and poly(methacrylate) could be ruled out. The developed EFV-loaded particles appear as a useful platform to investigate the intranasal administration to increase the bioavailability in the CNS.
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Affiliation(s)
- Katia P Seremeta
- The Group of Biomaterials and Nanotechnology for Improved Medicines (BIONIMED), Department of Pharmaceutical Technology, Faculty of Pharmacy and Biochemistry, University of Buenos Aires, 956 Junín St., Buenos Aires CP1113, Argentina
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Silva AL, Cristofoletti R, Storpirtis S, Sousa VD, Junginger HE, Shah VP, Stavchansky S, Dressman JB, Barends DM. Biowaiver Monographs for Immediate-Release Solid Oral Dosage Forms: Stavudine. J Pharm Sci 2012; 101:10-6. [DOI: 10.1002/jps.22756] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2011] [Accepted: 08/23/2011] [Indexed: 11/11/2022]
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Hurwitz SJ, Schinazi RF. In silico study supports the efficacy of a reduced dose regimen for stavudine. Antiviral Res 2011; 92:372-7. [PMID: 21875620 DOI: 10.1016/j.antiviral.2011.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 08/03/2011] [Accepted: 08/04/2011] [Indexed: 01/09/2023]
Abstract
Stavudine (d4T) is used extensively as part of HAART in resource poor settings, despite its toxicities. The revised WHO guidelines specify replacement of d4T with less toxic but more expensive drugs when feasible, and that d4T doses be standardized to 30 mg twice daily (bid) (irrespective of body-weight), from the approved 40 mg bid in adults (body-weight ≥60 kg). Therefore, an in silico population pharmacokinetic and biochemical model was utilized to compare relative efficacies of the two doses in humans. Assessment of predicted quartile ranges of simulated concentrations of the triphosphate of d4T suggested sufficient trough concentrations to inhibit wild type HIV-1 reverse transcriptase at the reduced dose, lending support to the revised WHO recommendations.
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Affiliation(s)
- Selwyn J Hurwitz
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
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Janneh O, Khoo SH. Interactions of tenofovir, Lamivudine, abacavir and Didanosine in primary human cells. Pharmaceutics 2011; 3:326-37. [PMID: 24310499 PMCID: PMC3864238 DOI: 10.3390/pharmaceutics3020326] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 06/08/2011] [Accepted: 06/21/2011] [Indexed: 12/04/2022] Open
Abstract
Certain triple nucleoside/tide reverse transcriptase inhibitor (NRTI) regimens containing tenofovir (TDF) have been associated with rapid early treatment failure. The mechanism is unknown, but may be at the level of drug transport. We measured the lipophilicity of the drugs [3H]-lamivudine (3TC), -didanosine (ddI), -TDF and -ABC. Peripheral blood mononuclear cells (PBMCs) were used to evaluate drug–drug interactions at the level of drug transport. PBMCs were measured for the expression of P-glycoprotein (P-gp), multidrug resistance-associated protein-1 (MRP-1) and breast cancer resistance protein (BCRP) by flow cytometry. The rank order of the lipophilicity of the drugs were ABC⋙3TC≥ddI>TDF. The accumulation of [3H]-3TC, -ddI and -TDF were temperature sensitive (suggesting facilitated transport), in contrast to [3H]-ABC. ABC reduced the accumulation of [3H]-3TC, and cell fractionation experiments suggested this was mainly in membrane-bound [3H]-3TC. ABC/TDF and ABC/ddI increased the accumulation of [3H]-3TC and 3TC/TDF also increased the accumulation of [3H]-TDF. In contrast, none of the NRTI/NtRTI incubations (alone or in combination) altered the accumulation of [3H]-ABC and -ddI. PBMC expression of P-gp, MRP1 and BCRP were detected, but none correlated with the accumulation of the drugs. The high failure rates seen with TDF, ABC and 3TC are not fully explained by an interaction at transporter level.
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Affiliation(s)
- Omar Janneh
- Department of Biomolecular and Sport Sciences, Coventry University, Priory Street, Coventry CV1 5FB, UK.
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Kohler JJ, Hosseini SH, Green E, Abuin A, Ludaway T, Russ R, Santoianni R, Lewis W. Tenofovir renal proximal tubular toxicity is regulated by OAT1 and MRP4 transporters. J Transl Med 2011; 91:852-8. [PMID: 21403643 PMCID: PMC3103636 DOI: 10.1038/labinvest.2011.48] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Tenofovir disoproxil fumarate (TDF) is an oral prodrug and acyclic nucleotide analog of adenosine monophosphate that inhibits HIV-1 (HIV) reverse transcriptase. A growing subset of TDF-treated HIV(+) individuals presented with acute renal failure, suggesting tenofovir-associated kidney-specific toxicity. Our previous studies using an HIV transgenic mouse model (TG) demonstrated specific changes in renal proximal tubular mitochondrial DNA (mtDNA) abundance. Nucleosides are regulated in biological systems via transport and metabolism in cellular compartments. In this study, the role(s) of organic anion transporter type 1 (OAT1) and multidrug-resistant protein type 4 (MRP4) in transport and regulation of tenofovir in proximal tubules were assessed. Renal toxicity was assessed in kidney tissues from OAT1 knockout (KO) or MRP4 KO compared with wild-type (WT, C57BL/6) mice following treatment with TDF (0.11 mg/day), didanosine (ddI, a related adenosine analog, 0.14 mg/day) or vehicle (0.1 M NaOH) daily gavage for 5 weeks. Laser-capture microdissection (LCM) was used to isolate renal proximal tubules for molecular analyses. mtDNA abundance and ultrastructural pathology were analyzed. mtDNA abundance in whole kidneys from both KO and WT was unchanged regardless of treatment. Renal proximal tubular mtDNA abundance from OAT1 KO also remained unchanged, suggesting prevention of TDF toxicity due to loss of tenofovir transport into proximal tubules. In contrast, renal proximal tubules from MRP4 KO exhibited increased mtDNA abundance following TDF treatment compared with WT littermates, suggesting compensation. Renal proximal tubules from TDF-treated WT and MRP4 KO exhibited increased numbers of irregular mitochondria with sparse, fragmented cristae compared with OAT1 KO. Treatment with ddI had a compensatory effect on mtDNA abundance in OAT1 KO but not in MRP4 KO. Both OAT1 and MRP4 have a direct role in transport and efflux of tenofovir, regulating levels of tenofovir in proximal tubules. Disruption of OAT1 activity prevents tenofovir toxicity but loss of MRP4 can lead to increased renal proximal tubular toxicity. These data help to explain mechanisms of human TDF renal toxicity.
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Affiliation(s)
- James J. Kohler
- Correspondence: Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA.
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Quevedo MA, Nieto LE, Briñón MC. P-glycoprotein limits the absorption of the anti-HIV drug zidovudine through rat intestinal segments. Eur J Pharm Sci 2011; 43:151-9. [DOI: 10.1016/j.ejps.2011.04.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 03/17/2011] [Accepted: 04/12/2011] [Indexed: 12/13/2022]
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Yan Z, Sun J, Chang Y, Liu Y, Fu Q, Xu Y, Sun Y, Pu X, Zhang Y, Jing Y, Yin S, Zhu M, Wang Y, He Z. Bifunctional Peptidomimetic Prodrugs of Didanosine for Improved Intestinal Permeability and Enhanced Acidic Stability: Synthesis, Transepithelial Transport, Chemical Stability and Pharmacokinetics. Mol Pharm 2011; 8:319-29. [DOI: 10.1021/mp100376q] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zhongtian Yan
- Beijing Winsunny Pharmaceutical Co., LTD, Beijing, 101113, China
| | | | | | | | | | | | | | | | | | - Yongkui Jing
- Division of Hematology/Oncology, Department of Medicine, Mount Sinai School of Medicine, New York, New York 10029-6547, United States
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Alvarez-Lorenzo C, Rey-Rico A, Brea J, Loza MI, Concheiro A, Sosnik A. Inhibition of P-glycoprotein pumps by PEO–PPO amphiphiles: branched versus linear derivatives. Nanomedicine (Lond) 2010; 5:1371-83. [DOI: 10.2217/nnm.10.53] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Inhibition of the activity of efflux transporters may relevantly improve the chemotherapy of cancer and infectious diseases. Aim: To explore the ability of poloxamines (Tetronic®, X-shaped structure with a central ethylendiamine group and four branches of poly[ethylene oxide]–poly[propylene oxide] [PEO–PPO]) to inhibit the activity of P-glycoprotein (P-gp) on Caco-2 cell monolayers and to elucidate the incidence of the molecular architecture of PEO–PPO block copolymers on the intracellular accumulation of a relevant substrate, doxorubicin, by comparison with poloxamers (Pluronic®, linear triblock copolymers), well-known inhibitors of this efflux transporter. Methods: Both pristine and N-methylated poloxamines displaying a wide range of molecular weights and EO/PO ratios were tested regarding cytocompatibility and accumulation of doxorubicin in Caco-2 monolayers. Verapamil was used as a control. Results: The most active anti-P-gp poloxamines (which enhanced two- to three-fold doxorubicin accumulation compared with verapamil) resulted to be pristine medium-to-high hydrophobic T304, T904, T1301, T901 and T150R1. A notable dependence of the anti-P-gp activity on the copolymer concentration was found. A joint diagram of the inhibitory activity of poloxamers and poloxamines as a function of the effective length of the PPO block is proposed. Conclusion: The anti-P-gp activity is maxima for block copolymers possessing a low-to-medium hydrophilic–lipophilic balance and an ‘effective number’ of PO units ranging from 30 to 50.
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Affiliation(s)
- Carmen Alvarez-Lorenzo
- Departamento de Farmacia y Tecnología Farmacéutica, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
- Instituto de Farmacia Industrial, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
| | - Ana Rey-Rico
- Departamento de Farmacia y Tecnología Farmacéutica, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
- Instituto de Farmacia Industrial, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
| | - Jose Brea
- Instituto de Farmacia Industrial, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
- Departamento de Farmacología, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
| | - Maria Isabel Loza
- Instituto de Farmacia Industrial, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
- Departamento de Farmacología, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
| | - Angel Concheiro
- Departamento de Farmacia y Tecnología Farmacéutica, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
- Instituto de Farmacia Industrial, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782-Santiago de Compostela, Spain
| | - Alejandro Sosnik
- The Group of Biomaterials & Nanotechnologies for Improved Medicines (BIONIMED), Department of Pharmaceutical Technology, Faculty of Pharmacy & Biochemistry, University of Buenos Aires, Argentina; Department of Pharmaceutical Technology, Faculty of Pharmacy & Biochemistry, University of Buenos Aires, 956 Junín St., 6th Floor, Buenos Aires CP1113, Argentina
- National Science Research Council (CONICET), 1113-Buenos Aires, Argentina
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Jonckers THM, Lin TI, Buyck C, Lachau-Durand S, Vandyck K, Van Hoof S, Vandekerckhove LAM, Hu L, Berke JM, Vijgen L, Dillen LLA, Cummings MD, de Kock H, Nilsson M, Sund C, Rydegård C, Samuelsson B, Rosenquist Å, Fanning G, Van Emelen K, Simmen K, Raboisson P. 2′-Deoxy-2′-spirocyclopropylcytidine Revisited: A New and Selective Inhibitor of the Hepatitis C Virus NS5B Polymerase. J Med Chem 2010; 53:8150-60. [DOI: 10.1021/jm101050a] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Tim H. M. Jonckers
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Tse-I Lin
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Christophe Buyck
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Sophie Lachau-Durand
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Koen Vandyck
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Steven Van Hoof
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Leen A. M. Vandekerckhove
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Lili Hu
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Jan Martin Berke
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Leen Vijgen
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Lieve L. A. Dillen
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Maxwell D. Cummings
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Herman de Kock
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | | | | | | | | | | | - Gregory Fanning
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Kristof Van Emelen
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Kenneth Simmen
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Pierre Raboisson
- Tibotec BVBA, A Division of Janssen Pharmaceutical Companies of Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium
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Janneh O, Owen A, Bray PG, Back DJ, Pirmohamed M. The accumulation and metabolism of zidovudine in 3T3-F442A pre-adipocytes. Br J Pharmacol 2009; 159:484-93. [PMID: 20015290 DOI: 10.1111/j.1476-5381.2009.00552.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE Cultured pre-adipocytes accumulate and metabolize zidovudine (ZDV), but its mode of accumulation into these cells is unclear. We investigated the mode of accumulation of [(3)H]-ZDV, and the impact of changes in external pH and modulators of drug transporters on its accumulation and metabolism. EXPERIMENTAL APPROACH The initial rate and steady-state accumulation of [(3)H]-ZDV were measured in 3T3-F442A cells. P-glycoprotein (P-gp) expression was detected by Western blotting. External pH was varied, and modulators of intracellular pH and drug transporters were used to study the mode of accumulation of ZDV. Phosphorylated ZDV metabolites were detected by high-performance liquid chromatography. KEY RESULTS Intracellular accumulation of ZDV was rapid, reaching equilibrium within 20 min; nigericin increased accumulation by 1.9-fold, but this did not alter the generation of ZDV mono-, di- and triphosphate. The accumulation and metabolism were pH dependent, being maximal at pH 7.4 and least at pH 5.1. Monensin, carbonyl cyanide p-trifluoromethoxy) phenyl hydrazone, brefeldin A, bafilomycin A1 and concanamycin A increased accumulation; 2-deoxyglucose, dipyridamole, thymidine and tetraphenylphosphonium inhibited accumulation. The accumulation was saturable; the derived K(d) and capacity of binding were 250 nmol per 10(6) cells and 265 nM respectively. 3T3-F442A cells express P-gp; inhibitors of P-gp (XR9576 and verapamil), P-gp/BCRP (GF120918), multidrug resistance protein (MRP) (MK571) and MRP/OATP (probenecid) increased the accumulation of ZDV. Saquinavir, ritonavir, amprenavir and lopinavir increased accumulation. CONCLUSIONS AND IMPLICATIONS The accumulation of ZDV in 3T3-F442A cells was rapid, energy dependent, saturable and pH sensitive. Western blot analysis showed that 3T3-F442A cells express P-gp, and direct inhibition assays suggest that ZDV is a substrate of P-gp and MRP.
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Affiliation(s)
- Omar Janneh
- Department of Biomolecular and Sports Sciences, Coventry University, Coventry, UK.
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Simultaneous determination of didanosine and its amino acid prodrug, valdidanosine by hydrophilic interaction chromatography coupled with electrospray ionization tandem mass spectrometry: application to a pharmacokinetic study in rats. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 878:466-70. [PMID: 20022566 DOI: 10.1016/j.jchromb.2009.11.041] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2009] [Revised: 11/10/2009] [Accepted: 11/20/2009] [Indexed: 11/21/2022]
Abstract
A rapid, sensitive and selective ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method with hydrophilic interaction chromatography has been developed and validated for the simultaneous determination of didanosine and valdidanosine (L-valine amino acid ester prodrug of didanosine) in rat plasma. Solid-phase extraction (SPE) column was employed to extract the analytes from rat plasma, with high extraction recovery (>85%) for both didanosine and valdidanosine. The analytes were then separated by hydrophilic interaction chromatography (HILIC column) and detected by a triple-quadrupole mass spectrometry equipped with an electrospray ionization (ESI) source. The method was linear over the concentration ranges of 2-20,000 ng/mL for didanosine and 4-300 ng/mL for valdidanosine. The lower limit of quantitation (LLOQ) of didanosine and valdidanosine was 2 and 4 ng/mL, respectively. The intra-day and inter-day relative standard deviation (RSD) were less than 15% and the relative errors (RE) were all within 15%. Finally, the validated UPLC-MS/MS method was successfully applied to the pharmacokinetic study after either didanosine or valdidanosine orally administrated to the Sprague-Dawley rats.
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Sosnik A, Chiappetta DA, Carcaboso ÁM. Drug delivery systems in HIV pharmacotherapy: What has been done and the challenges standing ahead. J Control Release 2009; 138:2-15. [DOI: 10.1016/j.jconrel.2009.05.007] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Accepted: 05/04/2009] [Indexed: 01/04/2023]
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Quevedo MA, Briñón MC. In vitro and in vivo pharmacokinetic characterization of two novel prodrugs of zidovudine. Antiviral Res 2009; 83:103-11. [DOI: 10.1016/j.antiviral.2009.03.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2009] [Revised: 03/18/2009] [Accepted: 03/27/2009] [Indexed: 01/15/2023]
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Majumdar S, Macha S, Pal D, Mitra AK. Mechanism of ganciclovir uptake by rabbit retina and human retinal pigmented epithelium cell line ARPE-19. Curr Eye Res 2009; 29:127-36. [PMID: 15512959 DOI: 10.1080/02713680490504678] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE The objective of this study was to elucidate the mechanism of ganciclovir uptake by the rabbit retina and the human retinal pigmented epithelium cell line ARPE-19. MATERIALS AND METHODS [(3)H]Adenine, [(3)H]adenosine, [(3)H]thymidine, and [(3)H]ganciclovir were used to elucidate the mechanism of ganciclovir uptake by the ARPE-19 cell line and the isolated rabbit retinal tissue. Uptake studies using ARPE-19 cell line and isolated rabbit retina were carried out at 37 degrees C and 25 degrees C, respectively, for 5 min. RESULTS Uptake of [(3)H]adenine by ARPE-19 cells decreased by 95% in the presence of unlabeled adenine. Other nucleobases such as guanine, thymine, and uracil and the nucleosides adenosine, guanosine, thymidine, uridine, and inosine also reduced uptake of [(3)H]adenine by the ARPE-19 cells. Although [(3)H]adenosine and [(3)H]thymidine uptake was inhibited by nucleosides, nucleobases did not demonstrate any inhibitory effect, indicating that nucleosides can only bind to the nucleobase transporter but are not translocated by it. Uptake of the nucleosides and nucleobases by the ARPE-19 cells was sodium and pH independent. [(3)H]adenosine and [(3)H]thymidine uptake by the ARPE-19 cells was inhibited by nanomolar quantities of nitrobenzylthioinosine. Uptake of [(3)H]adenine by the isolated rabbit retina was drastically reduced in the presence of unlabeled adenine. Unlabeled thymidine and guanosine, and removal of sodium from the uptake medium, inhibited uptake of [(3)H]thymidine by the rabbit retina. Nucleosides, nucleobases, and unlabeled ganciclovir did not exhibit any inhibitory effect on [(3)H]ganciclovir uptake by the isolated rabbit retina or ARPE-19 cells. CONCLUSIONS Our results indicate that although the rabbit retina and the ARPE-19 cell line express nucleoside and nucleobase transporters, translocation of ganciclovir does not involve any carrier-mediated transport process. Rather, ganciclovir uptake by the rabbit retina and ARPE-19 cells is governed primarily by passive diffusion.
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Affiliation(s)
- Soumyajit Majumdar
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64110-2499, USA
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Schinazi RF, Coats SJ, Bassit LC, Lennerstrand J, Nettles JH, Hurwitz SJ. Approaches for the development of antiviral compounds: the case of hepatitis C virus. Handb Exp Pharmacol 2009:25-51. [PMID: 19048196 DOI: 10.1007/978-3-540-79086-0_2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Traditional methods for general drug discovery typically include evaluating random compound libraries for activity in relevant cell-free or cell-based assays. Success in antiviral development has emerged from the discovery of more focused libraries that provide clues about structure activity relationships. Combining these with more recent approaches including structural biology and computational modeling can work efficiently to hasten discovery of active molecules, but that is not enough. There are issues related to biology, toxicology, pharmacology, and metabolism that have to be addressed before a hit compound becomes nominated for clinical development. The objective of gaining early preclinical knowledge is to reduce the risk of failure in Phases 1, 2, and 3, leading to the goal of approved drugs that benefit the infected individual. This review uses hepatitis C virus (HCV), for which we still do not have an ideal therapeutic modality, as an example of the multidisciplinary efforts needed to discover new antiviral drugs for the benefit of humanity.
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Affiliation(s)
- Raymond F Schinazi
- Laboratory of Biochemical Pharmacology, VA Medical Center, Emory University School of Medicine, 1670 Clairmont Road, Decatur, GA 30033, USA.
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Bourgeois J, Lalanne M, Pierson LA, Marsaud V, Nicolas V, Tsapis N, Ball R, Stanimirovic D, Couvreur P, Andrieux K. Formulation of glycerolipidic prodrugs into PEGylated liposomes for brain delivery. J Drug Deliv Sci Technol 2009. [DOI: 10.1016/s1773-2247(09)50008-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Development of an optimized dose for coformulation of zidovudine with drugs that select for the K65R mutation using a population pharmacokinetic and enzyme kinetic simulation model. Antimicrob Agents Chemother 2008; 52:4241-50. [PMID: 18838591 DOI: 10.1128/aac.00054-08] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
In vitro selection studies and data from large genotype databases from clinical studies have demonstrated that tenofovir disoproxil fumarate and abacavir sulfate select for the K65R mutation in the human immunodeficiency virus type 1 polymerase region. Furthermore, other novel non-thymine nucleoside reverse transcriptase (RT) inhibitors also select for this mutation in vitro. Studies performed in vitro and in humans suggest that viruses containing the K65R mutation remained susceptible to zidovudine (ZDV) and other thymine nucleoside antiretroviral agents. Therefore, ZDV could be coformulated with these agents as a "resistance repellent" agent for the K65R mutation. The approved ZDV oral dose is 300 mg twice a day (b.i.d.) and is commonly associated with bone marrow toxicity thought to be secondary to ZDV-5'-monophosphate (ZDV-MP) accumulation. A simulation study was performed in silico to optimize the ZDV dose for b.i.d. administration with K65R-selecting antiretroviral agents in virtual subjects using the population pharmacokinetic and cellular enzyme kinetic parameters of ZDV. These simulations predicted that a reduction in the ZDV dose from 300 to 200 mg b.i.d. should produce similar amounts of ZDV-5'-triphosphate (ZDV-TP) associated with antiviral efficacy (>97% overlap) and reduced plasma ZDV and cellular amounts of ZDV-MP associated with toxicity. The simulations also predicted reduced peak and trough amounts of cellular ZDV-TP after treatment with 600 mg ZDV once a day (q.d.) rather than 300 or 200 mg ZDV b.i.d., indicating that q.d. dosing with ZDV should be avoided. These in silico predictions suggest that 200 mg ZDV b.i.d. is an efficacious and safe dose that could delay the emergence of the K65R mutation.
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Hurwitz SJ, Asif G, Schinazi RF. Development of a population simulation model for HIV monotherapy virological outcomes using lamivudine. Antivir Chem Chemother 2008; 18:329-41. [PMID: 18320937 DOI: 10.1177/095632020701800605] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Current highly active antiretroviral therapy (HAART) requires the use of combinations of three drugs to minimize the early emergence of drug-resistant HIV strains. Therefore, long-term monotherapy data with new agents are unavailable. However, the development of computer models for Monte-Carlo-type simulations of antiviral monotherapy, which incorporate HIV infection dynamic distributions from previously studied populations, together with pharmacokinetics and pharmacodynamic parameters of the new agent, could serve as an important tool. The nucleoside lamivudine (3TC) was used as a representative drug to standardize an improved pharmacodynamic and infection dynamic monotherapy model. 3TC plasma concentration versus time profiles was used to drive the cellular accumulation of 3TC-triphosphate (TP) in primary human lymphocytes in the model, over a 16 week period. The fraction of HIV reverse transcription inhibited was calculated using the median inhibitory concentration and intracellular 3TC-TP levels. Virus loads and activated CD4+ T-cell counts were generated for 2,200 theoretical individuals and compared with the outcomes of an actual 3TC monotherapy trial at the same dose. Pharmacokinetic variance alone did not account for the interindividual HIV-load variability. However, selection of appropriate distributions of the various pharmacokinetic and infection dynamics parameters produced a similar range of virus load reductions to actual observations. Therefore, once parameter and variance distributions are standardized, this modelling approach could be helpful in planning clinical trials and predicting the antiviral contribution of each agent in a HAART modality.
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Affiliation(s)
- Selwyn J Hurwitz
- Center for AIDS Research and Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA.
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Li F, Maag H, Alfredson T. Prodrugs of nucleoside analogues for improved oral absorption and tissue targeting. J Pharm Sci 2008; 97:1109-34. [PMID: 17696166 DOI: 10.1002/jps.21047] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Nucleoside analogues are widely used for the treatment of antiviral infections and anticancer chemotherapy. However, many nucleoside analogues suffer from poor oral bioavailability due to their high polarity and low intestinal permeability. In order to improve oral absorption of these polar drugs, prodrugs have been employed to increase lipophilicity by chemical modification of the parent. Alternatively, prodrugs targeting transporters present in the intestine have been exploited to facilitate the transport of the nucleoside analogues. Valacyclovir and valganciclovir are two successful valine ester prodrugs transported by the PepT1 transporter. Recently, research efforts have focused on design of prodrugs for tissue specific delivery to improve efficacy and safety. This review presents advances of prodrug approaches for improved oral absorption of nucleoside analogues and recent developments in tissue targeting.
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Affiliation(s)
- Fujun Li
- Department of Pharmaceutics, Roche Palo Alto LLC, 3431 Hillview Avenue, Palo Alto, CA 94304, USA.
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Lalanne M, Andrieux K, Paci A, Besnard M, Ré M, Bourgaux C, Ollivon M, Desmaele D, Couvreur P. Liposomal formulation of a glycerolipidic prodrug for lymphatic delivery of didanosine via oral route. Int J Pharm 2007; 344:62-70. [PMID: 17616448 DOI: 10.1016/j.ijpharm.2007.05.064] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2007] [Revised: 05/24/2007] [Accepted: 05/25/2007] [Indexed: 11/23/2022]
Abstract
Didanosine is a polar drug with poor membrane absorption and high hepatic first pass metabolism. This study aimed at developing a lipidic formulation of a glycerolipidic prodrug of didanosine in order to improve its bioavailability. In the course of a preformulation study, the glycerolipidic prodrug of didanosine was characterized by microscopy, DSC and XRDT. In anhydrous conditions, the prodrug displayed a polymorphic behaviour similar to that of triglycerides. Then, we evaluated three types of lipidic formulations (emulsions, mixed micelles and liposomes) in order to encapsulate the prodrug. Solubilities in water - even in the presence of taurocholate micelles - but also in some oils were very low (max 244 microg/mL) as the prodrug was found to be amphiphilic (log P=2). On the contrary, the prodrug was found to be perfectly incorporated in dipalmitoylphosphatidylcholine (DPPC) multilamellar liposomes up to a ratio of 1:5 (mol:mol) prodrug:DPPC as suggested by HPLC-UV and DSC experiments. Moreover, these liposomes could be freeze-dried whereas the chemical integrity of the prodrug was preserved. Then, the freeze-dried liposomal preparation could be formulated as gastro-resistant capsules to prevent didanosine from acidic degradation. Further experiments are on the way to evaluate in vitro the absorption of prodrug incorporated in liposomes by enterocytes.
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Affiliation(s)
- M Lalanne
- Univ. Paris-Sud, UMR CNRS 8612, IFR 141, F-92296 Châtenay-Malabry, France
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Hecker SJ, Reddy KR, van Poelje PD, Sun Z, Huang W, Varkhedkar V, Reddy MV, Fujitaki JM, Olsen DB, Koeplinger KA, Boyer SH, Linemeyer DL, MacCoss M, Erion MD. Liver-Targeted Prodrugs of 2‘-C-Methyladenosine for Therapy of Hepatitis C Virus Infection. J Med Chem 2007; 50:3891-6. [PMID: 17636948 DOI: 10.1021/jm0701021] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
2'-C-Methyladenosine exhibits impressive inhibitory activity in the cell-based hepatitis C virus (HCV) subgenomic replicon assay, by virtue of intracellular conversion to the corresponding nucleoside triphosphate (NTP) and inhibition of NS5B RNA-dependent RNA polymerase (RdRp). However, rapid degradation by adenosine deaminase (ADA) limits its overall therapeutic potential. To reduce ADA-mediated deamination, we prepared cyclic 1-aryl-1,3-propanyl prodrugs of the corresponding nucleoside monophosphate (NMP), anticipating cytochrome P450 3A-mediated oxidative cleavage to the NMP in hepatocytes. Lead compounds identified in a primary rat hepatocyte screen were shown to result in liver levels of NTP predictive of efficacy after intravenous dosing to rats. The oral bioavailability of the initial lead was below 5%; therefore, additional analogues were synthesized and screened for liver NTP levels after oral administration to rats. Addition of a 2',3'-carbonate prodrug moiety proved to be a successful strategy, and the 1-(4-pyridyl)-1,3-propanyl prodrug containing a 2',3'-carbonate moiety displayed oral bioavailability of 39%.
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Affiliation(s)
- Scott J Hecker
- Departments of Biochemistry and Medicinal Chemistry, Metabasis Therapeutics, Inc., 11119 North Torrey Pines Road, La Jolla, CA 92037, USA.
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40
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Kim HR, Park SW, Cho HJ, Chae KA, Sung JM, Kim JS, Landowski CP, Sun D, Abd El-Aty AM, Amidon GL, Shin HC. Comparative gene expression profiles of intestinal transporters in mice, rats and humans. Pharmacol Res 2007; 56:224-36. [PMID: 17681807 DOI: 10.1016/j.phrs.2007.06.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2007] [Revised: 05/10/2007] [Accepted: 06/01/2007] [Indexed: 10/23/2022]
Abstract
We have studied gene expression profiles of intestinal transporters in model animals and humans. Total RNA was isolated from duodenum and the mRNA expression was measured using Affymetrix GeneChip oligonucleotide arrays. Detected genes from the intestine of mice, rats, and humans were about 60% of 22,690 sequences, 40% of 8739, and 47% of 12,559, respectively. A total of 86 genes involving transporters expressed in mice, 50 genes in rats, and 61 genes in humans were detected. Mice exhibited abundant mRNA expressions for peptide transporter HPT1, amino acid transporters CSNU3, CT1 and ASC1, nucleoside transporter CNT2, organic cation transporter SFXN1, organic anion transporter NBC3, glucose transporter SGLT1, and fatty acid transporters FABP1 and FABP2. Rats showed high expression profiles of peptide transporter PEPT1, amino acid transporters CSNU1 and 4F2HC, nucleoside transporter CNT2, organic cation transporter OCT5, organic anion transporter SDCT1, glucose transporter GLUT2 and GLUT5, and folate carrier FOLT. In humans, the highly expressed genes were peptide transporter HPT1, amino acid transporters LAT3, 4F2HC and PROT, nucleoside transporter CNT2, organic cation transporter OCTN2, organic anion transporters NADC1, NBC1 and SBC2, glucose transporters SGLT1 and GLUT5, multidrug resistance-associated protein RHO12, fatty acid transporters FABP1 and FABP2, and phosphate carrier PHC. Overall these data reveal diverse transcriptomic profiles for intestinal transporters among these species. Therefore, this transcriptional data may lead to more effective use of the laboratory animals as a model for oral drug development.
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Affiliation(s)
- Hye-Ryoung Kim
- Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, Seoul 143-701, Republic of Korea
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Lalanne M, Paci A, Andrieux K, Dereuddre-Bosquet N, Clayette P, Deroussent A, Ré M, Vassal G, Couvreur P, Desmaële D. Synthesis and biological evaluation of two glycerolipidic prodrugs of didanosine for direct lymphatic delivery against HIV. Bioorg Med Chem Lett 2007; 17:2237-40. [PMID: 17276686 DOI: 10.1016/j.bmcl.2007.01.062] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2006] [Revised: 01/18/2007] [Accepted: 01/19/2007] [Indexed: 11/29/2022]
Abstract
Novel glycerolipidic prodrugs of didanosine and didanosine monophosphate designed to by-pass the hepatic first pass metabolism were synthesized and tested for their cytotoxicity and anti-HIV-1 activity. Formulation as liposomes of dipalmitoylphosphatidylcholine was elaborated. A simple quantitative HPLC-UV method was developed and validated, and ESI-MS was used for qualitative purpose. These two prodrugs exhibited promising biological activities against HIV-1 in in vitro infected cell culture.
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Affiliation(s)
- Muriel Lalanne
- Université Paris-Sud, UMR CNRS 8612, IFR 141, F-92296 Châtenay-Malabry, France
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Holen E, Bjørge OA, Jonsson R. Dietary nucleotides and human immune cells. II. Modulation of PBMC growth and cytokine secretion. Nutrition 2006; 22:90-6. [PMID: 16615178 DOI: 10.1016/j.nut.2006.01.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVE The immune system is dependent on purines and pyrimidines as building blocks for DNA and RNA synthesis to enable rapid cell proliferation and protein synthesis. Emerging evidence suggests that dietary nucleotides optimize immune function. We investigated whether growth and function of human immune cells were affected by an exogenous source of nucleotides during specific antigen challenge. METHODS Peripheral blood mononuclear cells from healthy individuals (n = 10) were stimulated with influenza virus antigen and either DNA sodium from fish soft roe (DNA), RNA from bakers yeast (Saccharomyces cerevisiae) (RNA), 2' deoxyadenosine 5'-monophosphate sodium (dAMP), 2' deoxycytidine 5'-monophosphate sodium (dCMP), 2' deoxyguanosine 5'-monophosphate sodium (dGMP), 2' deoxyuridine 5'-monophosphate sodium (dUMP) or thymidine sodium (TMP). Growth effects were ascertained by measuring the amount of tritium-labeled thymidine, incorporated into cell DNA. Cell function was measured by detection of IFN-gamma, TNF-alpha and IL-10 production. RESULTS Specific nucleotide derivatives alone did not affect the growth of healthy peripheral blood mononuclear cells. However, the nucleotide derivatives influenced immune cell growth and cytokine secretion when cocultured with specific antigen. DNA, RNA, dAMP, dCMP and dUMP increased influenza virus antigen induced immune cell proliferation. In contrast dGMP and TMP inhibited the antigen-induced growth response. RNA and dAMP cocultured with virus antigen significantly increased peripheral blood mononuclear cell secretion of IFN-gamma, IL-10 and TNF-alpha. DNA increased virus antigen-induced immune cell secretion of IFN-gamma only, whereas dUMP significantly increased secretion of IL-10 only. dGMP completely inhibited virus-triggered IFN-gamma secretion, whereas TMP did not change the virus induced secretion pattern of measured cytokines. CONCLUSION Nucleotide derivatives affect growth and function of specific virus antigen-stimulated human immune cells in vitro.
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Affiliation(s)
- Elisabeth Holen
- Broegelmann Research Laboratory, University of Bergen, Norway.
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Shin HC, Kim JS, Vig BS, Song X, Drach JC, Amidon GL. Interaction of intestinal nucleoside transporter hCNT2 with amino acid ester prodrugs of floxuridine and 2-bromo-5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole. Biol Pharm Bull 2006; 29:247-52. [PMID: 16462026 DOI: 10.1248/bpb.29.247] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Amino acid ester prodrugs of antiviral and anticancer nucleoside drugs were developed to improve oral bioavailability or to reduce systemic toxicity. We studied the interaction of human concentrative nucleoside transporter (hCNT2) cloned from intestine with various amino acid ester prodrugs of floxuridine (FUdR) and 5,6-dichloro-2-bromo-1-beta-D-ribofuranosylbenzimidazole (BDCRB). Na(+)-dependent uptakes of [(3)H]-inosine and [(3)H]-adenosine were measured in U251 cells transiently expressing intestinal hCNT2. FUdR significantly inhibited the uptake of both [(3)H]-inosine and [(3)H]-adenosine (60-70% of control), while its amino acid ester prodrugs including Val, Phe, Pro, Asp, and Lys esters exhibited markedly decreased inhibition potency (10-30% of control). On the other hand, BDCRB and its amino acid prodrugs markedly inhibited the uptake of both [(3)H]-inosine and [(3)H]-adenosine. Val, Phe, and Pro ester prodrugs of BDCRB showed similar inhibition capacities as parent compound BDCRB (80-90% for adenosine and 60-80% for inosine). The amino acid site of attachment (3'- and 5'-monoesters) and stereochemistry (L- and D-amino acid esters), did not significantly affect the uptake of [(3)H]-inosine and [(3)H]-adenosine. These results demonstrate that the hCNT2 favorably interacts with BDCRB and its amino acid prodrugs, compared to those of FUdR, and that neutral amino acid esters of BDCRB have a high affinity toward this transporter. Therefore, the intestinal hCNT2 may be a target transporter as a factor for modulating oral pharmacokinetics of BDCRB prodrugs.
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Affiliation(s)
- Ho-Chul Shin
- Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, Seoul 143-701, Korea.
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Holen E, Bjørge OA, Jonsson R. Dietary nucleotides and human immune cells. II. Modulation of PBMC growth and cytokine secretion. Nutrition 2006; 21:1003-9. [PMID: 16157237 DOI: 10.1016/j.nut.2005.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2004] [Accepted: 03/24/2005] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The immune system is dependent on purines and pyrimidines as building blocks for DNA and RNA synthesis to enable rapid cell proliferation and protein synthesis. Emerging evidence suggests that dietary nucleotides optimize immune function. We investigated whether growth and function of human immune cells were affected by an exogenous source of nucleotides during specific antigen challenge. METHODS Peripheral blood mononuclear cells from healthy individuals (n = 10) were stimulated with influenza virus antigen and DNA-Na+ from fish soft roe, RNA from bakers yeast (Saccharomyces cerevisiae), 2'deoxyadenosine 5'-monophosphate sodium, 2'deoxycytidine 5'-monophosphate sodium, 2'deoxyguanosine 5'-monophosphate sodium, or 2'deoxyuridine 5'-monophosphate disodium. Growth effects were ascertained by measuring the amount of tritium-labeled Thymidine 5'-monophosphate sodium incorporated into cell DNA. Cell function was measured by detection of interferon-gamma (IFN-gamma), tumor necrosis factor-alpha, and interleukin-10 production. RESULTS Specific nucleotide derivatives alone did not affect the growth of healthy peripheral blood mononuclear cells. However, the nucleotide derivatives influenced immune cell growth and cytokine secretion when cocultured with specific antigen. DNA, RNA, deoxyadenosine monophosphate, deoxycytidine monophosphate, and deoxyuridine monophosphate increased influenza virus antigen-induced immune cell proliferation. In contrast, deoxyadenosine monophosphate and thymosine monophosphate inhibited the antigen-induced growth response. RNA and deoxyadenosine monophosphate cocultured with virus antigen significantly increased peripheral blood mononuclear cell secretion of IFN-gamma, interleukin-10, and tumor necrosis factor-alpha. DNA increased virus antigen-induced immune cell secretion of IFN-gamma only, whereas deoxyuridine monophosphate significantly increased secretion of interleukin-10 only. Deoxyguanosine monophosphate completely inhibited virus-triggered IFN-gamma secretion, whereas thymosine monophosphate did not change the secretion pattern of measured cytokines. CONCLUSION Nucleotide derivatives affect growth and function of specific virus antigen-stimulated human immune cells in vitro.
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Affiliation(s)
- Elisabeth Holen
- Broegelmann Research Laboratory, University of Bergen, Bergen, Norway.
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Endres CJ, Sengupta DJ, Unadkat JD. Mutation of leucine-92 selectively reduces the apparent affinity of inosine, guanosine, NBMPR [S6-(4-nitrobenzyl)-mercaptopurine riboside] and dilazep for the human equilibrative nucleoside transporter, hENT1. Biochem J 2004; 380:131-7. [PMID: 14759222 PMCID: PMC1224139 DOI: 10.1042/bj20031880] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2003] [Revised: 01/30/2004] [Accepted: 02/03/2004] [Indexed: 11/17/2022]
Abstract
We developed a yeast-based assay for selection of hENT1 (human equilibrative nucleoside transporter 1) mutants that have altered affinity for hENT1 inhibitors and substrates. In this assay, expression of hENT1 in a yeast strain deficient in adenine biosynthesis (ade2) permits yeast growth on a plate lacking adenine but containing adenosine, a hENT1 substrate. This growth was prevented when inhibitors of hENT1 [e.g. NBMPR [S6-(4-nitrobenzyl)-mercaptopurine riboside], dilazep or dipyridamole] were included in the media. To identify hENT1 mutants resistant to inhibition by these compounds, hENT1 was randomly mutagenized and introduced into this strain. Mutation(s) that allowed growth of yeast cells in the presence of these inhibitors were then identified and characterized. Mutants harbouring amino acid changes at Leu92 exhibited resistance to NBMPR and dilazep but not dipyridamole. The IC50 values of NBMPR and dilazep for [3H]adenosine transport by one of these mutants L92Q (Leu92-->Gln) were approx. 200- and 4-fold greater when compared with the value for the wild-type hENT1, whereas that for dipyridamole remained unchanged. Additionally, when compared with the wild-type transporter, [3H]adenosine transport by L92Q transporter was significantly resistant to inhibition by inosine and guanosine but not by adenosine or pyrimidines. The Km value for inosine transport was approx. 4-fold greater for the L92Q mutant (260+/-16 mM) when compared with the wild-type transporter (65+/-7.8 mM). We have identified for the first time an amino acid residue (Leu92) of hENT1 that, when mutated, selectively alters the affinity of hENT1 to transport the nucleosides inosine and guanosine and its sensitivity to the inhibitors NBMPR and dilazep.
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Affiliation(s)
- Christopher J Endres
- Department of Pharmaceutics, University of Washington, Box 357610, Seattle, WA 98195, USA
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Majumdar S, Duvvuri S, Mitra AK. Membrane transporter/receptor-targeted prodrug design: strategies for human and veterinary drug development. Adv Drug Deliv Rev 2004; 56:1437-52. [PMID: 15191791 DOI: 10.1016/j.addr.2004.02.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2003] [Accepted: 02/18/2004] [Indexed: 01/12/2023]
Abstract
The bioavailability of drugs is often severely limited due to the presence of biological barriers in the form of epithelial tight junctions, efflux proteins and enzymatic degradation. Physicochemical properties, such as lipophilicity, molecular weight, charge, etc., also play key roles in determining the permeation properties of drug candidates. As a result, many potential drug candidates may be dropped from the initial screening portfolio. Prodrug derivatization targeting transporters and receptors expressed on mammalian cells holds tremendous potential. Enhanced cellular delivery can significantly improve drug absorption. Such approaches of drug targeting and delivery have been the subject of intense research. Various prodrugs have been designed that demonstrate enhanced bioavailability and tissue specificity. This approach is equally applicable to human and veterinary pharmaceuticals since most of the transporters and receptors expressed by human tissues are also expressed in animals. This review highlights studies conducted on the use of transporters and receptors in an effort to improve drug bioavailability and to develop targeted drug delivery systems.
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Affiliation(s)
- Soumyajit Majumdar
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 5005 Rockhill Road, Kansas City, MO 64110, USA
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Patel J, Hussain A, Pal D, Mitra AK. A Mathematical Simulation to Explain the Coordinated Functions of Efflux and Metabolism Limiting the Transport of Anti-HIV Agents Across Caco-2 Cells. Am J Ther 2004; 11:114-23. [PMID: 14999363 DOI: 10.1097/00045391-200403000-00006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The purpose of this study was to simulate a mathematical model that explains the coordinated function of P-glycoprotein (P-gp) and/or CYP3A4 in human intestinal enterocytes. In addition, this study aimed to determine the efflux interactions of anti-HIV protease inhibitors. METHODS Human colon carcinoma-derived Caco-2 cells were selected as a model system to evaluate the effects of P-gp-mediated efflux of HIV protease inhibitors. Anti-HIV agents ritonavir and saquinavir were selected as model drugs to determine efflux interactions. An absorption-metabolism classification system is hence proposed based on substrate specificities of drugs toward P-gp and/or CYP3A4 and their probable interactions with other compounds. RESULTS Enhanced apical to basal (A-B) ritonavir transport was observed on coadministration of saquinavir. Saturable, concentration-dependent inhibition of ritonavir efflux from Caco-2 monolayers was also observed with saquinavir. The IC(50) values of ritonavir (as a self-inhibitor) and saquinavir from dose-response curves, estimated by fitting the data to nonlinear equations, were found to be 7.15 and 33.2 micromol/L, respectively. The respective K(i) values determined were 8.5 and 28.91 micromol/L. The experimentally obtained K(i) values decreased in the close approximation with the IC(50) values. CONCLUSION Proposed mathematical simulations may prove to be a useful tool in predicting drug interactions by inhibition of P-gp mediated efflux and CYP3A4-mediated metabolism.
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Affiliation(s)
- Jignesh Patel
- Wyeth Research, 401 N Middletown Rd, Pearl River, NY 10965, USA
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48
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Shin HC, Landowski CP, Sun D, Vig BS, Kim I, Mittal S, Lane M, Rosania G, Drach JC, Amidon GL. Functional expression and characterization of a sodium-dependent nucleoside transporter hCNT2 cloned from human duodenum. Biochem Biophys Res Commun 2003; 307:696-703. [PMID: 12893280 DOI: 10.1016/s0006-291x(03)01259-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We have cloned and functionally expressed a sodium-dependent human nucleoside transporter, hCNT2, from a CNS cancer cell line U251. Our cDNA clone of hCNT2 had the same predicted amino acid sequence as the previously cloned hCNT2 transporter. Of the several cell lines studied, the best hCNT2 transport function was obtained when transiently expressed in U251 cells. Na(+)-dependent uptake of [3H]inosine in U251 cells transiently expressing hCNT2 was 50-fold greater than that in non-transfected cells, and uptake in Na(+)-containing medium was approximately 30-fold higher than that at Na(+)-free condition. The hCNT2 displayed saturable uptake of [3H]inosine with K(m) of 12.8 microM and V(max) of 6.66 pmol/mg protein/5 min. Uptake of [3H]inosine was significantly inhibited by the purine nucleoside drugs dideoxyinosine and cladribine, but not by acyclic nucleosides including acyclovir, ganciclovir, and their prodrugs valacyclovir and valganciclovir. This indicates that the closed ribose ring is important for binding of nucleoside drugs to hCNT2. Among several pyrimidine nucleosides, hCNT2 favorably interacted with the uridine analogue floxuridine. Interestingly, we found that benzimidazole analogues, including maribavir, 5,6-dichloro-2-bromo-1-beta-D-ribofuranosylbenzimidazole (BDCRB), and 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB), were strong inhibitors of inosine transport, even though they have a significantly different heterocycle structure compared to a typical purine ring. As measured by GeneChip arrays, mRNA expression of hCNT2 in human duodenum was 15-fold greater than that of hCNT1 or hENT2. Further, the rCNT2 expression in rat duodenum was 20-fold higher than rCNT1, rENT1 or rENT2. This suggests that hCNT2 (and rCNT2) may have a significant role in uptake of nucleoside drugs from the intestine and is a potential transporter target for the development of nucleoside and nucleoside-mimetic drugs.
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Affiliation(s)
- Ho-Chul Shin
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
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Majumdar S, Tirucherai GS, Pal D, Mitra AK. Functional differences in nucleoside and nucleobase transporters expressed on the rabbit corneal epithelial cell line (SIRC) and isolated rabbit cornea. AAPS PHARMSCI 2003; 5:E15. [PMID: 12866942 PMCID: PMC2751523 DOI: 10.1208/ps050215] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The purpose of this study was to investigate the expression of nucleoside/nucleobase transporters on the Statens Seruminstitut rabbit corneal (SIRC) epithelial cell line and to evaluate SIRC as an in vitro screening tool for delineating the mechanism of corneal permeation of nucleoside analogs. SIRC cells (passages 410-425) were used to study uptake of [3H]thymidine, [3H]adenine, and [3H]ganciclovir. Transport of [3H]adenine and [3H]ganciclovir was studied across isolated rabbit cornea. Uptake and transport studies were performed for 2 minutes and 120 minutes, respectively, at 34 degrees C. Thymidine uptake by SIRC displayed saturable kinetics (K(m) = 595.9 +/- 80.4 microM, and V(max) = 289.5 +/- 17.2 pmol/min/mg protein). Uptake was inhibited by both purine and pyrimidine nucleosides but not by nucleobases. [3H]thymidine uptake was sodium and energy independent but was inhibited by nitrobenzylthioinosine at nanomolar concentrations. Adenine uptake by SIRC consisted of a saturable component (K(m) = 14.4 +/- 2.3 microM, V(max) = 0.4 +/- 0.04 nmol/min/mg protein) and a nonsaturable component. Uptake of adenine was inhibited by purine nucleobases but not by the nucleosides or pyrimidine nucleobases and was independent of sodium, energy, and nitrobenzylthioinosine. [3H]ganciclovir uptake involved a carrier-mediated component and was inhibited by the purine nucleobases but not by the nucleosides or pyrimidine nucleobases. However, transport of [3H]adenine across the isolated rabbit cornea was not inhibited by unlabeled adenine. Further, corneal permeability of ganciclovir across a 100-fold concentration range remained constant, indicating that ganciclovir permeates the cornea primarily by passive diffusion. Nucleoside and nucleobase transporters on rabbit cornea and corneal epithelial cell line, SIRC, are functionally different, undermining the utility of the SIRC cell line as an in vitro screening tool for elucidating the corneal permeation mechanism of nucleoside analogs.
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Affiliation(s)
- Soumyajit Majumdar
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 5005 Rockhill Road, 64110 Kansas City, MO
| | - Giridhar S. Tirucherai
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 5005 Rockhill Road, 64110 Kansas City, MO
- Department of Clinical Pharmacology, Quintiles Inc, 10245 Hickman Mills Drive, 64137 Kansas City, MO
| | - Dhanajay Pal
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 5005 Rockhill Road, 64110 Kansas City, MO
| | - Ashim K. Mitra
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 5005 Rockhill Road, 64110 Kansas City, MO
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Desmoulin F, Gilard V, Malet-Martino M, Martino R. Metabolism of capecitabine, an oral fluorouracil prodrug: (19)F NMR studies in animal models and human urine. Drug Metab Dispos 2002; 30:1221-9. [PMID: 12386128 DOI: 10.1124/dmd.30.11.1221] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Capecitabine (Xeloda; CAP) is a recently developed oral antineoplastic prodrug of 5-fluorouracil (5-FU) with enhanced tumor selectivity. Previous studies have shown that CAP activation follows a pathway with three enzymatic steps and two intermediary metabolites, 5'-deoxy-5-fluorocytidine (5'-DFCR) and 5'-deoxy-5-fluorouridine (5'-DFUR), to form 5-FU preferentially in tumor tissues. In the present work, we investigated all fluorinated compounds present in liver, bile, and perfusate medium of isolated perfused rat liver (IPRL) and in liver, plasma, kidneys, bile, and urine of healthy rats. Moreover, data obtained from rat urine were compared with those from mice and human urine. According to a low cytidine deaminase (3.5.4.5) activity in rats, 5'-DFCR was by far the main product in perfusate medium from IPRL and plasma and urine from rats. Liver and circulating 5'-DFCR in perfusate and plasma equilibrated at the same concentration value in the range 25 to 400 microM, which supports the involvement of es-type nucleoside transporter in the liver. 5'-DFUR and alpha-fluoro-beta-ureidopropionic acid (FUPA) + alpha-fluoro-beta-alanine (FBAL) were the main products in urine of mice, making up 23 to 30% of the administered dose versus 3 to 4% in rat. In human urine, FUPA + FBAL represented 50% of the administered dose, 5'-DFCR 10%, and 5'-DFUR 7%. Since fluorine-19 nuclear magnetic resonance spectroscopy gives an overview of all the fluorinated compounds present in a sample, we observed the following unreported metabolites of CAP: 1) 5-fluorocytosine and its hydroxylated metabolite, 5-fluoro-6-hydroxycytosine, 2) fluoride ion, 3) 2-fluoro-3-hydroxypropionic acid and fluoroacetate, and 4) a glucuroconjugate of 5'-DFCR.
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Affiliation(s)
- Franck Desmoulin
- Groupe de Résonance Magnétique Nucléaire Biomédicale, Unité Mixte Recherche Centre National de la Recherche Scientifique 5623, Université Paul Sabatier, Toulouse, France.
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