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Gniech T, Humboldt A, Keith KA, James SH, Richert C. A ProTide of AZT Shows Activity Against Human Papillomaviruses. ChemMedChem 2024; 19:e202300661. [PMID: 38241205 DOI: 10.1002/cmdc.202300661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 01/18/2024] [Accepted: 01/18/2024] [Indexed: 01/21/2024]
Abstract
Infection by human papillomaviruses (HPV) can cause warts and tumors. So far, no small molecule antiviral has been approved for the treatment of infections with this DNA virus, although preclinical studies show activity for nucleosidic compounds, such as 9-(2-phosphonylmethoxy)ethylguanine (PMEG) or cidofovir. This prompted us to test new prodrug versions of the nucleoside analog 3'-azido-2',3'-dideoxythymidine (AZT), known to be active against reverse transcriptases and approved for the treatment of HIV. Here we report the synthesis of an ethylbutyl alaninyl ester phosphosphoramidate prodrug of AZT, dubbed AZAEB, and its activity against HPV, a target not known to be sensitive to AZT. A methyl ester derivative was found to be inactive against this and three other DNA viruses, while the phosphoramidate prodrug AZAEB showed a modest inhibitory effect against HPV types 6, 11, 18 and 31. Our results open up new avenues of study for the treatment of diseases caused by members of the papillomaviridae family.
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Affiliation(s)
- Tim Gniech
- Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Adrian Humboldt
- Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Kathy A Keith
- Department of Pediatrics, Division of Pediatric Infectious Diseases, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Scott H James
- Department of Pediatrics, Division of Pediatric Infectious Diseases, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Clemens Richert
- Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
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2
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Kovalishyn V, Severin O, Kachaeva M, Kobzar O, Keith KA, Harden EA, Hartline CB, James SH, Vovk A, Brovarets V. In Silico Design and Experimental Validation of Novel Oxazole Derivatives Against Varicella zoster virus. Mol Biotechnol 2024; 66:707-717. [PMID: 36709460 DOI: 10.1007/s12033-023-00670-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 01/14/2023] [Indexed: 01/30/2023]
Abstract
Varicella zoster virus (VZV) infection causes severe disease such as chickenpox, shingles, and postherpetic neuralgia, often leading to disability. Reactivation of latent VZV is associated with a decrease in specific cellular immunity in the elderly and in patients with immunodeficiency. However, due to the limited efficacy of existing therapy and the emergence of antiviral resistance, it has become necessary to develop new and effective antiviral drugs for the treatment of diseases caused by VZV, particularly in the setting of opportunistic infections. The goal of this work is to identify potent oxazole derivatives as anti-VZV agents by machine learning, followed by their synthesis and experimental validation. Predictive QSAR models were developed using the Online Chemical Modeling Environment (OCHEM). Data on compounds exhibiting antiviral activity were collected from the ChEMBL and uploaded in the OCHEM database. The predictive ability of the models was tested by cross-validation, giving coefficient of determination q2 = 0.87-0.9. The validation of the models using an external test set proves that the models can be used to predict the antiviral activity of newly designed and known compounds with reasonable accuracy within the applicability domain (q2 = 0.83-0.84). The models were applied to screen a virtual chemical library with expected activity of compounds against VZV. The 7 most promising oxazole derivatives were identified, synthesized, and tested. Two of them showed activity against the VZV Ellen strain upon primary in vitro antiviral screening. The synthesized compounds may represent an interesting starting point for further development of the oxazole derivatives against VZV. The developed models are available online at OCHEM http://ochem.eu/article/145978 and can be used to virtually screen for potential compounds with anti-VZV activity.
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Affiliation(s)
- Vasyl Kovalishyn
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Science of Ukraine, Kyiv, 02094, Ukraine.
| | - Oleksandr Severin
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Science of Ukraine, Kyiv, 02094, Ukraine
| | - Maryna Kachaeva
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Science of Ukraine, Kyiv, 02094, Ukraine
| | - Oleksandr Kobzar
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Science of Ukraine, Kyiv, 02094, Ukraine
| | - Kathy A Keith
- Department of Pediatrics, Division of Pediatric Infectious Diseases, University of Alabama at Birmingham, Birmingham, Alabama, 35233, USA
| | - Emma A Harden
- Department of Pediatrics, Division of Pediatric Infectious Diseases, University of Alabama at Birmingham, Birmingham, Alabama, 35233, USA
| | - Caroll B Hartline
- Department of Pediatrics, Division of Pediatric Infectious Diseases, University of Alabama at Birmingham, Birmingham, Alabama, 35233, USA
| | - Scott H James
- Department of Pediatrics, Division of Pediatric Infectious Diseases, University of Alabama at Birmingham, Birmingham, Alabama, 35233, USA
| | - Andriy Vovk
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Science of Ukraine, Kyiv, 02094, Ukraine
| | - Volodymyr Brovarets
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Science of Ukraine, Kyiv, 02094, Ukraine
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Lipka E, Chadderdon AM, Harteg CC, Doherty MK, Simon ES, Domagala JM, Reyna DM, Hutchings KM, Gan X, White AD, Hartline CB, Harden EA, Keith KA, Prichard MN, James SH, Cardin RD, Bernstein DI, Spencer JF, Tollefson AE, Wold WSM, Toth K. NPP-669, a Novel Broad-Spectrum Antiviral Therapeutic with Excellent Cellular Uptake, Antiviral Potency, Oral Bioavailability, Preclinical Efficacy, and a Promising Safety Margin. Mol Pharm 2023; 20:370-382. [PMID: 36484496 PMCID: PMC9811456 DOI: 10.1021/acs.molpharmaceut.2c00668] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
DNA viruses are responsible for many diseases in humans. Current treatments are often limited by toxicity, as in the case of cidofovir (CDV, Vistide), a compound used against cytomegalovirus (CMV) and adenovirus (AdV) infections. CDV is a polar molecule with poor bioavailability, and its overall clinical utility is limited by the high occurrence of acute nephrotoxicity. To circumvent these disadvantages, we designed nine CDV prodrug analogues. The prodrugs modulate the polarity of CDV with a long sulfonyl alkyl chain attached to one of the phosphono oxygens. We added capping groups to the end of the alkyl chain to minimize β-oxidation and focus the metabolism on the phosphoester hydrolysis, thereby tuning the rate of this reaction by altering the alkyl chain length. With these modifications, the prodrugs have excellent aqueous solubility, optimized metabolic stability, increased cellular permeability, and rapid intracellular conversion to the pharmacologically active diphosphate form (CDV-PP). The prodrugs exhibited significantly enhanced antiviral potency against a wide range of DNA viruses in infected human foreskin fibroblasts. Single-dose intravenous and oral pharmacokinetic experiments showed that the compounds maintained plasma and target tissue levels of CDV well above the EC50 for 24 h. These experiments identified a novel lead candidate, NPP-669. NPP-669 demonstrated efficacy against CMV infections in mice and AdV infections in hamsters following oral (p.o.) dosing at a dose of 1 mg/kg BID and 0.1 mg/kg QD, respectively. We further showed that NPP-669 at 30 mg/kg QD did not exhibit histological signs of toxicity in mice or hamsters. These data suggest that NPP-669 is a promising lead candidate for a broad-spectrum antiviral compound.
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Affiliation(s)
- Elke Lipka
- TSRL,
Inc., 540 Avis Dr., Suite
A, Ann Arbor, Michigan 48108, United States,. Phone: 734-663-4233 ext. 236. Fax: 734-663-3607
| | | | - Cheryl C. Harteg
- TSRL,
Inc., 540 Avis Dr., Suite
A, Ann Arbor, Michigan 48108, United States
| | - Matthew K. Doherty
- TSRL,
Inc., 540 Avis Dr., Suite
A, Ann Arbor, Michigan 48108, United States
| | - Eric S. Simon
- TSRL,
Inc., 540 Avis Dr., Suite
A, Ann Arbor, Michigan 48108, United States
| | - John M. Domagala
- TSRL,
Inc., 540 Avis Dr., Suite
A, Ann Arbor, Michigan 48108, United States
| | - Dawn M. Reyna
- TSRL,
Inc., 540 Avis Dr., Suite
A, Ann Arbor, Michigan 48108, United States
| | - Kim M. Hutchings
- College
of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Xinmin Gan
- College
of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Andrew D. White
- College
of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Caroll B. Hartline
- Department
of Pediatrics, University of Alabama School
of Medicine, Birmingham, Alabama 35233, United
States
| | - Emma A. Harden
- Department
of Pediatrics, University of Alabama School
of Medicine, Birmingham, Alabama 35233, United
States
| | - Kathy A. Keith
- Department
of Pediatrics, University of Alabama School
of Medicine, Birmingham, Alabama 35233, United
States
| | - Mark N. Prichard
- Department
of Pediatrics, University of Alabama School
of Medicine, Birmingham, Alabama 35233, United
States
| | - Scott H. James
- Department
of Pediatrics, University of Alabama School
of Medicine, Birmingham, Alabama 35233, United
States
| | - Rhonda D. Cardin
- School
of Veterinary Medicine, Louisiana State
University, Baton
Rouge, Louisiana 70803, United States
| | - David I. Bernstein
- Cincinnati
Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio 45229, United States
| | | | - Ann E. Tollefson
- Saint Louis
University School of Medicine, St. Louis, Missouri 63104, United States
| | - William S. M. Wold
- Saint Louis
University School of Medicine, St. Louis, Missouri 63104, United States
| | - Karoly Toth
- Saint Louis
University School of Medicine, St. Louis, Missouri 63104, United States
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Hartline CB, Keith KA, Eagar J, Harden EA, Bowlin TL, Prichard MN. A standardized approach to the evaluation of antivirals against DNA viruses: Orthopox-, adeno-, and herpesviruses. Antiviral Res 2018; 159:104-112. [PMID: 30287226 DOI: 10.1016/j.antiviral.2018.09.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 09/25/2018] [Accepted: 09/28/2018] [Indexed: 01/07/2023]
Abstract
The search for new compounds with a broad spectrum of antiviral activity is important and requires the evaluation of many compounds against several distinct viruses. Researchers attempting to develop new antiviral therapies for DNA virus infections currently use a variety of cell lines, assay conditions and measurement methods to determine in vitro drug efficacy, making it difficult to compare results from within the same laboratory as well as between laboratories. In this paper we describe a common assay platform designed to facilitate the parallel evaluation of antiviral activity against herpes simplex virus type 1, herpes simplex virus type 2, varicella-zoster virus, cytomegalovirus, vaccinia virus, cowpox virus, and adenovirus. The automated assays utilize monolayers of primary human foreskin fibroblast cells in 384-well plates as a common cell substrate and cytopathic effects and cytotoxicity are quantified with CellTiter-Glo. Data presented demonstrate that each of the assays is highly robust and yields data that are comparable to those from other traditional assays, such as plaque reduction assays. The assays proved to be both accurate and robust and afford an in depth assessment of antiviral activity against the diverse class of viruses with very small quantities of test compounds. In an accompanying paper, we present a standardized approach to evaluating antivirals against lymphotropic herpesviruses and polyomaviruses and together these studies revealed new activities for reference compounds. This approach has the potential to accelerate the development of broad spectrum therapies for the DNA viruses.
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Affiliation(s)
- Caroll B Hartline
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, 35233, United States
| | - Kathy A Keith
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, 35233, United States
| | - Jessica Eagar
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, 35233, United States
| | - Emma A Harden
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, 35233, United States
| | | | - Mark N Prichard
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL, 35233, United States.
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5
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Beadle JR, Valiaeva N, Yang G, Yu JH, Broker TR, Aldern KA, Harden EA, Keith KA, Prichard MN, Hartman T, Buckheit RW, Chow LT, Hostetler KY. Synthesis and Antiviral Evaluation of Octadecyloxyethyl Benzyl 9-[(2-Phosphonomethoxy)ethyl]guanine (ODE-Bn-PMEG), a Potent Inhibitor of Transient HPV DNA Amplification. J Med Chem 2016; 59:10470-10478. [PMID: 27933957 DOI: 10.1021/acs.jmedchem.6b00659] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Human papillomavirus (HPV) high-risk genotypes such as HPV-16 and HPV-18 cause the majority of anogenital tract carcinomas, including cervical cancer, the second most common malignancy in women worldwide. Currently there are no approved antiviral agents that reduce or eliminate HPV and reverse virus-associated pathology. We synthesized and evaluated several alkoxyalkyl acyclic nucleoside phosphonate diesters and identified octadecyloxyethyl benzyl 9-[(2-phosphonomethoxy)ethyl]guanine (ODE-Bn-PMEG) as an active compound which strongly inhibited transient amplification of HPV-11, -16, and -18 origin-containing plasmid DNA in transfected cells at concentrations well below its cytotoxic concentrations. ODE-Bn-PMEG demonstrated increased uptake in human foreskin fibroblast cells and was readily converted in vitro to the active antiviral metabolite, PMEG diphosphate. The P-chiral enantiomers of ODE-Bn-PMEG were obtained and appeared to have equivalent antiviral activities against HPV. ODE-Bn-PMEG is a promising candidate for the local treatment of HPV-16 and HPV-18 and other high-risk types, an important unmet medical need.
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Affiliation(s)
- James R Beadle
- University of California, San Diego , La Jolla, California 92093, United States
| | - Nadejda Valiaeva
- University of California, San Diego , La Jolla, California 92093, United States
| | - Guang Yang
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Jei-Hwa Yu
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Thomas R Broker
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Kathy A Aldern
- University of California, San Diego , La Jolla, California 92093, United States
| | - Emma A Harden
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Kathy A Keith
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Mark N Prichard
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Tracy Hartman
- ImQuest BioSciences , Frederick, Maryland 21704, United States
| | | | - Louise T Chow
- University of Alabama at Birmingham , Birmingham, Alabama 35233, United States
| | - Karl Y Hostetler
- University of California, San Diego , La Jolla, California 92093, United States.,Antiva Biosciences, Inc. , South San Francisco, California 94080, United States
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Selvam P, Murugesh N, Chandramohan M, Keith KA, Kern ER. Inhibitory Activity of 4-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene)amino]-N-(4,6-dimethylpyrimidin-2-yl) Benzenesulphonamide and its Derivatives against Orthopoxvirus Replication in vitro. ACTA ACUST UNITED AC 2016; 17:107-10. [PMID: 17042332 DOI: 10.1177/095632020601700206] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
4-[(1,2-Dihydro-2-oxo-3H-indol-3-ylidene)amino]-N-(4,6-dimethylpyrimidin-2-yl) benzenesulphonamide and its derivatives were tested in vitro for antiviral activity against vaccinia and cowpox virus replication in human foreskin fibroblast (HFF) cells, and their activity was compared with cidofovir (CDV). Among the tested compounds, 4-[(5-methyl-1,2-dihydro-2-oxo-3-H-indol-3-ylidene)amino]- N-(4,6-dimethylpyrimidin-2-yl)benzene-sulphonamide was the most active against vaccinia virus, with a 50% effective concentration (EC50) value of 18 µM and 4-[(N-acetyl-1,2–dihydro-2-oxo-3-H-indol-3-ylidene)amino]- N-(4,6-dimethylpyrimidin-2-yl) benzenesulphonamide was the most active against cowpox virus (EC50=33 µM). Cidofovir was found to have an EC50 of 20 µM and 32 µM against vaccinia and cowpox virus, respectively. Most of the tested compounds were non-cytotoxic (>300 µM) in HFF cells as determined by a neutral red uptake assay. The substitution of a halogen atom at the 5-position of isatin abolished the antiviral activity.
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Affiliation(s)
- Periyasamy Selvam
- Arulmigu Kalasalingam College of Pharmacy, Anandnagar, Krishnankoil, Tamilnadu, India.
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Williams JD, Khan AR, Harden EA, Hartline CB, Jefferson GM, Keith KA, Prichard MN, Zemlicka J, Peet NP, Bowlin TL. Synthesis and antiviral activity of certain second generation methylenecyclopropane nucleosides. Bioorg Med Chem 2012; 20:3710-8. [PMID: 22607883 DOI: 10.1016/j.bmc.2012.04.049] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 04/17/2012] [Accepted: 04/25/2012] [Indexed: 11/15/2022]
Abstract
A second-generation series of substituted methylenecyclopropane nucleosides (MCPNs) has been synthesized and evaluated for antiviral activity against a panel of human herpesviruses, and for cytotoxicity. Although alkylated 2,6-diaminopurine analogs showed little antiviral activity, the compounds containing ether and thioether substituents at the 6-position of the purine did demonstrate potent and selective antiviral activity against several different human herpesviruses. In the 6-alkoxy series, antiviral activity depended on the length of the ether carbon chain, with the optimum chain length being about four carbon units long. For the corresponding thioethers, compounds containing secondary thioethers were more potent than those with primary thioethers.
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Affiliation(s)
- John D Williams
- Microbiotix, Inc., One Innovation Drive, Worcester, MA 01605, USA.
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Valiaeva N, Prichard MN, Buller RM, Beadle JR, Hartline CB, Keith KA, Schriewer J, Trahan J, Hostetler KY. Antiviral evaluation of octadecyloxyethyl esters of (S)-3-hydroxy-2-(phosphonomethoxy)propyl nucleosides against herpesviruses and orthopoxviruses. Antiviral Res 2009; 84:254-9. [PMID: 19800369 DOI: 10.1016/j.antiviral.2009.09.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 09/22/2009] [Accepted: 09/23/2009] [Indexed: 11/27/2022]
Abstract
Our previous studies showed that esterification of 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine (HPMPA) or 1-(S)-[3-hydroxy-2-(phosphonomethoxy)-propyl]cytosine (HPMPC) with alkoxyalkyl groups such as hexadecyloxypropyl (HDP) or octadecyloxyethyl (ODE) resulted in large increases in antiviral activity and oral bioavailability. The HDP and ODE esters of HPMPA were shown to be active in cells infected with human immunodeficiency virus, type 1 (HIV-1), while HPMPA itself was virtually inactive. To explore this approach in greater detail, we synthesized four new compounds in this series, the ODE esters of 9-(S)-[3-hydroxy-2-(phosphonomethoxy)-propyl]guanine (HPMPG), 1-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]thymine (HPMPT), 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]-2,6-diaminopurine (HPMPDAP) and 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]-2-amino-6-cyclopropylaminopurine (HPMP-cPrDAP) and evaluated their antiviral activity against herpes simplex virus, type 1 (HSV-1), human cytomegalovirus (HCMV), and vaccinia, cowpox and ectromelia. Against HSV-1, subnanomolar EC(50) values were observed with ODE-HPMPA and ODE-HPMPC while ODE-HPMPG had intermediate antiviral activity with an EC(50) of 40 nM. In HFF cells infected with HCMV, the lowest EC(50) values were observed with ODE-HPMPC, 0.9 nM. ODE-HPMPA was highly active with an EC(50) of 3 nM, while ODE-HPMPG and ODE-HPMPDAP were also highly active with EC(50)s of 22 and 77 nM, respectively. Against vaccinia and cowpox viruses, ODE-HPMPG and ODE-HPMPDAP were the most active and selective compounds with EC(50) values of 20-60 nM and selectivity index values of 600-3500. ODE-HPMPG was also active against ectromelia virus with an EC(50) value of 410 nM and a selectivity index value of 166. ODE-HPMPG and ODE-HPMPDAP are proposed for further preclinical evaluation as possible candidates for treatment of HSV, HCMV or orthopoxvirus diseases.
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Affiliation(s)
- Nadejda Valiaeva
- Department of Medicine, Division of Infectious Disease, University of California, San Diego, La Jolla, CA 92093-0676, USA
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9
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Valiaeva N, Trahan J, Keith KA, Hartline C, Prichard M, Beadle JR, Hostetler KY. Evaluation of Octadecyloxyethyl Esters of 3-Hydroxy-2-(phosphonomethoxy)propyl Nucleosides Against HCMV, HSV and Poxviruses. Antiviral Res 2009. [DOI: 10.1016/j.antiviral.2009.02.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Becker MN, Obraztsova M, Kern ER, Quenelle DC, Keith KA, Prichard MN, Luo M, Moyer RW. Isolation and characterization of cidofovir resistant vaccinia viruses. Virol J 2008; 5:58. [PMID: 18479513 PMCID: PMC2397383 DOI: 10.1186/1743-422x-5-58] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Accepted: 05/14/2008] [Indexed: 12/04/2022] Open
Abstract
Background The emergence of drug resistant viruses, together with the possibility of increased virulence, is an important concern in the development of new antiviral compounds. Cidofovir (CDV) is a phosphonate nucleotide that is approved for use against cytomegalovirus retinitis and for the emergency treatment of smallpox or complications following vaccination. One mode of action for CDV has been demonstrated to be the inhibition of the viral DNA polymerase. Results We have isolated several CDV resistant (CDVR) vaccinia viruses through a one step process, two of which have unique single mutations within the DNA polymerase. An additional resistant virus isolate provides evidence of a second site mutation within the genome involved in CDV resistance. The CDVR viruses were 3–7 fold more resistant to the drug than the parental viruses. The virulence of the CDVR viruses was tested in mice inoculated intranasally and all were found to be attenuated. Conclusion Resistance to CDV in vaccinia virus can be conferred individually by at least two different mutations within the DNA polymerase gene. Additional genes may be involved. This one step approach for isolating resistant viruses without serial passage and in the presence of low doses of drug minimizes unintended secondary mutations and is applicable to other potential antiviral agents.
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Prichard MN, Kern ER, Quenelle DC, Keith KA, Moyer RW, Turner PC. Vaccinia virus lacking the deoxyuridine triphosphatase gene (F2L) replicates well in vitro and in vivo, but is hypersensitive to the antiviral drug (N)-methanocarbathymidine. Virol J 2008; 5:39. [PMID: 18321387 PMCID: PMC2276199 DOI: 10.1186/1743-422x-5-39] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Accepted: 03/05/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The vaccinia virus (VV) F2L gene encodes a functional deoxyuridine triphosphatase (dUTPase) that catalyzes the conversion of dUTP to dUMP and is thought to minimize the incorporation of deoxyuridine residues into the viral genome. Previous studies with with a complex, multigene deletion in this virus suggested that the gene was not required for viral replication, but the impact of deleting this gene alone has not been determined in vitro or in vivo. Although the crystal structure for this enzyme has been determined, its potential as a target for antiviral therapy is unclear. RESULTS The F2L gene was replaced with GFP in the WR strain of VV to assess its effect on viral replication. The resulting virus replicated well in cell culture and its replication kinetics were almost indistinguishable from those of the wt virus and attained similar titers. The virus also appeared to be as pathogenic as the WR strain suggesting that it also replicated well in mice. Cells infected with the dUTPase mutant would be predicted to affect pyrimidine deoxynucleotide pools and might be expected to exhibit altered susceptibility to pyrimidine analogs. The antiviral activity of cidofovir and four thymidine analogs were evaluated both in the mutant and the parent strain of this virus. The dUTPase knockout remained fully susceptible to cidofovir and idoxuridine, but was hypersensitive to the drug (N)-methanocarbathymidine, suggesting that pyrimidine metabolism was altered in cells infected with the mutant virus. The absence of dUTPase should reduce cellular dUMP pools and may result in a reduced conversion to dTMP by thymidylate synthetase or an increased reliance on the salvage of thymidine by the viral thymidine kinase. CONCLUSION We confirmed that F2L was not required for replication in cell culture and determined that it does not play a significant role on virulence of the virus in intranasally infected mice. The recombinant virus is hypersensitive to (N)-methanocarbathymidine and may reflect metabolic differences in the mutant virus.
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Affiliation(s)
- Mark N Prichard
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL 35233, USA.
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12
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Quenelle DC, Collins DJ, Herrod BP, Keith KA, Trahan J, Beadle JR, Hostetler KY, Kern ER. Effect of oral treatment with hexadecyloxypropyl-[(S)-9-(3-hydroxy-2- phosphonylmethoxypropyl)adenine] [(S)-HPMPA] or octadecyloxyethyl-(S)-HPMPA on cowpox or vaccinia virus infections in mice. Antimicrob Agents Chemother 2007; 51:3940-7. [PMID: 17846137 PMCID: PMC2151427 DOI: 10.1128/aac.00184-07] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have previously reported that (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine, or (S)-HPMPA, is active in vitro against cowpox virus (CV) and vaccinia virus (VV) but is not active orally in animals. However, the ether lipid esters of (S)-HPMPA, hexadecyloxypropyl-[(S)-HPMPA] [HDP-(S)-HPMPA] and octadecyloxyethyl-[(S)-HPMPA] [ODE-(S)-HPMPA], had significantly enhanced activity in vitro and are orally bioavailable in mice. In the current study, HDP-(S)-HPMPA and ODE-(S)-HPMPA were prepared in water and administered once daily by oral gavage to mice at doses of 30, 10, and 3 mg/kg of body weight for 5 days beginning 24, 48, or 72 h after inoculation with CV or VV. Oral HDP-(S)-HPMPA and ODE-(S)-HPMPA were both highly effective (P < 0.001) at preventing mortality due to CV at 30 mg/kg, even when treatments were delayed until up to 72 h postinfection. ODE-(S)-HPMPA or HDP-(S)-HPMPA were also highly effective (P < 0.001) at preventing mortality in mice infected with VV at 30 mg/kg when treatments were delayed until to 48 or 72 h postinfection, respectively. Protection against both viruses was associated with a significant reduction of virus replication in the liver, spleen, and kidney but not in the lung. These data indicate that HDP-(S)-HPMPA and ODE-(S)-HPMPA are active when given orally against lethal CV and VV infections in mice, and further evaluation is warranted to provide additional information on the potential of these orally active compounds for treatment of human orthopoxvirus infection.
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Affiliation(s)
- Debra C Quenelle
- Department of Pediatrics, The University of Alabama at Birmingham, School of Medicine, CHB 128, 1600 6th Avenue South, Birmingham, AL 35233, USA.
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Quenelle DC, Prichard MN, Keith KA, Hruby DE, Jordan R, Painter GR, Robertson A, Kern ER. Synergistic efficacy of the combination of ST-246 with CMX001 against orthopoxviruses. Antimicrob Agents Chemother 2007; 51:4118-24. [PMID: 17724153 PMCID: PMC2151443 DOI: 10.1128/aac.00762-07] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The combination of ST-246 and hexadecyloxypropyl-cidofovir or CMX001 was evaluated for synergistic activity in vitro against vaccinia virus and cowpox virus (CV) and in vivo against CV. In cell culture the combination was highly synergistic against both viruses, and the results suggested that combined treatment with these agents might offer superior efficacy in vivo. For animal models, ST-246 was administered orally with or without CMX001 to mice lethally infected with CV. Treatments began 1, 3, or 6 days postinfection using lower dosages than previously used for single-drug treatment. ST-246 was given at 10, 3, or 1 mg/kg of body weight with or without CMX001 at 3, 1, or 0.3 mg/kg to evaluate potential synergistic interactions. Treatment beginning 6 days post-viral inoculation with ST-246 alone only increased the mean day to death at 10 or 3 mg/kg but had no effect on survival. CMX001 alone also had no effect on survival. When the combination of the two drugs was begun 6 days after viral infection using various dosages of the two, a synergistic reduction in mortality was observed. No evidence of increased toxicity was noted with the combination either in vitro or in vivo. These results indicate that combinations of ST-246 and CMX001 are synergistic both in vitro and in vivo and suggest that combination therapy using ST-246 and CMX001 for treatment of orthopoxvirus disease in humans or animals may provide an additional benefit over the use of the two drugs by themselves.
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Affiliation(s)
- Debra C Quenelle
- Department of Pediatrics, The University of Alabama at Birmingham, Birmingham, AL 35233-1711, USA.
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14
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Bailey TR, Rippin SR, Opsitnick E, Burns CJ, Pevear DC, Collett MS, Rhodes G, Tohan S, Huggins JW, Baker RO, Kern ER, Keith KA, Dai D, Yang G, Hruby D, Jordan R. N-(3,3a,4,4a,5,5a,6,6a-Octahydro-1,3-dioxo-4,6- ethenocycloprop[f]isoindol-2-(1H)-yl)carboxamides: Identification of novel orthopoxvirus egress inhibitors. J Med Chem 2007; 50:1442-4. [PMID: 17335190 PMCID: PMC4067006 DOI: 10.1021/jm061484y] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of novel, potent orthopoxvirus egress inhibitors was identified during high-throughput screening of the ViroPharma small molecule collection. Using structure--activity relationship information inferred from early hits, several compounds were synthesized, and compound 14 was identified as a potent, orally bioavailable first-in-class inhibitor of orthopoxvirus egress from infected cells. Compound 14 has shown comparable efficaciousness in three murine orthopoxvirus models and has entered Phase I clinical trials.
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Affiliation(s)
- Thomas R Bailey
- ViroPharma Incorporated, 397 Eagleview Boulevard, Exton, Pennsylvania 19341, USA.
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15
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Prichard MN, Keith KA, Johnson MP, Harden EA, McBrayer A, Luo M, Qiu S, Chattopadhyay D, Fan X, Torrence PF, Kern ER. Selective phosphorylation of antiviral drugs by vaccinia virus thymidine kinase. Antimicrob Agents Chemother 2007; 51:1795-803. [PMID: 17325220 PMCID: PMC1855528 DOI: 10.1128/aac.01447-06] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The antiviral activity of a new series of thymidine analogs was determined against vaccinia virus (VV), cowpox virus (CV), herpes simplex virus, and varicella-zoster virus. Several compounds were identified that had good activity against each of the viruses, including a set of novel 5-substituted deoxyuridine analogs. To investigate the possibility that these drugs might be phosphorylated preferentially by the viral thymidine kinase (TK) homologs, the antiviral activities of these compounds were also assessed using TK-deficient strains of some of these viruses. Some of these compounds were shown to be much less effective in the absence of a functional TK gene in CV, which was unexpected given the high degree of amino acid identity between this enzyme and its cellular homolog. This unanticipated result suggested that the CV TK was important in the mechanism of action of these compounds and also that it might phosphorylate a wider variety of substrates than other type II enzymes. To confirm these data, we expressed the VV TK and human TK1 in bacteria and isolated the purified enzymes. Enzymatic assays demonstrated that the viral TK could efficiently phosphorylate many of these compounds, whereas most of the compounds were very poor substrates for the cellular kinase, TK1. Thus, the specific phosphorylation of these compounds by the viral kinase may be sufficient to explain the TK dependence. This unexpected result suggests that selective phosphorylation by the viral kinase may be a promising new approach in the discovery of highly selective inhibitors of orthopoxvirus replication.
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Affiliation(s)
- Mark N Prichard
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL 35233, USA.
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16
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Choo H, Beadle JR, Kern ER, Prichard MN, Keith KA, Hartline CB, Trahan J, Aldern KA, Korba BE, Hostetler KY. Antiviral activities of novel 5-phosphono-pent-2-en-1-yl nucleosides and their alkoxyalkyl phosphonoesters. Antimicrob Agents Chemother 2006; 51:611-5. [PMID: 17130297 PMCID: PMC1797766 DOI: 10.1128/aac.00444-06] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Three acyclic nucleoside phosphonates are currently approved for clinical use against infections caused by cytomegalovirus (Vistide), hepatitis B virus (Hepsera), and human immunodeficiency virus type 1 (Viread). This important antiviral class inhibits viral polymerases after cellular uptake and conversion to their diphosphates, bypassing the first phosphorylation, which is required for conventional nucleoside antivirals. Small chemical alterations in the acyclic side chain lead to marked differences in antiviral activity and the spectrum of activity of acyclic nucleoside phosphonates against various classes of viral agents. We synthesized a new class of acyclic nucleoside phosphonates based on a 5-phosphono-pent-2-en-1-yl base motif in which the oxygen heteroatom usually present in acyclic nucleoside phosphonates has been replaced with a double bond. Since the intrinsic phosphonate moiety leads to low oral bioavailability and impaired cellular penetration, we also prepared the hexadecyloxypropyl esters of the 5-phosphono-pent-2-en-1-yl nucleosides. Our earlier work showed that this markedly increases antiviral activity and oral bioavailability. Although the 5-phosphono-pent-2-en-1-yl nucleosides themselves were not active, the hexadecyloxypropyl esters were active against DNA viruses and hepatitis B virus, in vitro. Notably, the hexadecyloxypropyl ester of 9-(5-phosphono-pent-2-en-1-yl)-adenine was active against hepatitis B virus mutants resistant to lamivudine, emtricitabine, and adefovir.
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Affiliation(s)
- Hyunah Choo
- Department of Medicine (0676), University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0676, USA
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17
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Quenelle DC, Buller RML, Parker S, Keith KA, Hruby DE, Jordan R, Kern ER. Efficacy of delayed treatment with ST-246 given orally against systemic orthopoxvirus infections in mice. Antimicrob Agents Chemother 2006; 51:689-95. [PMID: 17116683 PMCID: PMC1797744 DOI: 10.1128/aac.00879-06] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ST-246 was evaluated for activity against cowpox virus (CV), vaccinia virus (VV), and ectromelia virus (ECTV) and had an in vitro 50% effective concentration (EC50) of 0.48 microM against CV, 0.05 microM against VV, and 0.07 microM against ECTV. The selectivity indices were >208 and >2,000 for CV and VV, respectively. The in vitro antiviral activity of ST-246 was significantly greater than that of cidofovir, which had an EC50 of 41.1 microM against CV and 29.2 microM against VV, with selectivity indices of >7 and >10, respectively. ST-246 administered once daily by oral gavage to mice infected intranasally with CV beginning 4 h or delayed until 72 h postinoculation was highly effective when given for a 14-day duration using 100, 30, or 10 mg/kg of body weight. When 100 mg/kg of ST-246 was administered to VV-infected mice, a duration of 5 days was sufficient to significantly reduce mortality even when treatment was delayed 24 h postinoculation. Viral replication in liver, spleen, and kidney, but not lung, of CV- or VV-infected mice was reduced by ST-246 compared to levels for vehicle-treated mice. When 100 mg/kg of ST-246 was given once daily to mice infected by the intranasal route with ECTV, treatment for 10 days prevented mortality even when treatment was delayed up to 72 h after viral inoculation. Viral replication in target organs of ECTV-infected mice was also reduced.
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Affiliation(s)
- Debra C Quenelle
- University of Alabama at Birmingham, School of Medicine, Department of Pediatrics, 128 Children's Harbor Building, 1600 6th Avenue South, Birmingham, AL 35233-1711, USA.
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18
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Ruiz JC, Beadle JR, Aldern KA, Keith KA, Hartline CB, Kern ER, Hostetler KY. Synthesis and antiviral evaluation of alkoxyalkyl-phosphate conjugates of cidofovir and adefovir. Antiviral Res 2006; 75:87-90. [PMID: 17367874 PMCID: PMC1899528 DOI: 10.1016/j.antiviral.2006.09.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Revised: 09/13/2006] [Accepted: 09/16/2006] [Indexed: 11/24/2022]
Abstract
Esterification of cidofovir (CDV), an antiviral nucleoside phosphonate, with alkyl or alkoxyalkyl groups increases antiviral activity by enhancing cell uptake and conversion to CDV diphosphate. Hexadecyloxypropyl-CDV (HDP-CDV) has been shown to be 40-100 times more active than CDV in vitro in cells infected with herpes group viruses, variola, cowpox, vaccinia or ectromelia viruses. Since the first phosphorylation of CDV may be rate limiting, we synthesized the hexadecyloxypropyl-phosphate (HDP-P-) and octadecyloxyethyl-phosphate (ODE-P-) conjugates of CDV and phosphonomethoxy-ethyl-adenine (PMEA, adefovir). We tested the CDV analogs in cells infected with human cytomegalovirus, herpes simplex virus, cowpox virus and vaccinia virus; the analogs of PMEA were tested in cells infected with the human immunodeficiency virus, type 1. In general, the alkoxyalkyl-phosphate conjugates of CDV were substantially more active than CDV. HDP-P-CDV and ODE-P-CDV were 4.6-40 times more active against HCMV and 7-30 times more active against cowpox and vaccinia in vitro. Although the compounds of this type were more cytotoxic than the unmodified bases, their selectivity for virally infected cells was generally greater than the parent nucleotides except that HDP-P-PMEA showed little or no selectivity in HIV-1 infected MT-2 cells. Although the new compounds with an interposed phosphate were generally less active than the corresponding alkoxyalkyl esters of CDV and PMEA, the present approach provides a possible alternative method for enhancing the antiviral activity of drugs of this class.
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Affiliation(s)
- Jacqueline C Ruiz
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0676, United States
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19
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Fan X, Zhang X, Zhou L, Keith KA, Prichard MN, Kern ER, Torrence PF. Toward orthopoxvirus countermeasures: a novel heteromorphic nucleoside of unusual structure. J Med Chem 2006; 49:4052-4. [PMID: 16821766 PMCID: PMC4298854 DOI: 10.1021/jm060404n] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Two privileged drug scaffolds have been hybridized to create the novel heteromorphic nucleoside 5-(2-amino-3-cyano-5-oxo-5,6,7,8-tetrahydro-4H-chromen-4-yl)-1-(2-deoxypentofuranosyl)pyrimidine-2,4(1H,3H)-dione (2). Compound 2 inhibited the replication of two orthopoxviruses, vaccinia virus (VV) (EC(50) = 4.6 +/- 2.0 microM), and cowpox virus (CV) (EC(50) = 2.0 +/- 0.3 microM). Compound 2 exhibited reduced activity against a thymidine kinase (TK) negative strain of CV, implying a requirement for 5'-monophosphorylation for antiorthopoxvirus activity. Compound 2 was efficiently phosphorylated by VV TK, establishing that VV TK is more promiscuous than previously believed.
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Affiliation(s)
| | | | | | | | | | | | - Paul F. Torrence
- To whom correspondence should be addressed. Phone: 928-523-0298. Fax: 928-523-8111.
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20
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Fan X, Zhang X, Zhou L, Keith KA, Kern ER, Torrence PF. Assembling a smallpox biodefense by interrogating 5-substituted pyrimidine nucleoside chemical space. Antiviral Res 2006; 71:201-5. [PMID: 16759713 DOI: 10.1016/j.antiviral.2006.04.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Accepted: 04/19/2006] [Indexed: 11/20/2022]
Abstract
The nucleoside 5-formyl-2'-deoxyuridine has been used as a starting point for the generation of novel 5-substituted pyrimidine nucleosides that are shown to possess significant antiviral activity against two representative orthopoxviruses, namely vaccinia virus and cowpox virus.
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Affiliation(s)
- Xuesen Fan
- Department of Chemistry and Biochemistry, Northern Arizona University, Flagstaff, AZ 86011, USA
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21
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Fan X, Zhang X, Zhou L, Keith KA, Kern ER, Torrence PF. 5-(Dimethoxymethyl)-2'-deoxyuridine: a novel gem diether nucleoside with anti-orthopoxvirus activity. J Med Chem 2006; 49:3377-82. [PMID: 16722657 PMCID: PMC4262926 DOI: 10.1021/jm0601710] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To provide potential new leads for the treatment of orthopoxvirus infections, the 5-position of the pyrimidine nucleosides have been modified with a gem diether moiety to yield the following new nucleosides: 5-(dimethoxymethyl)-2'-deoxyuridine (2b), 5-(diethoxymethyl)-2'-deoxyuridine (3b), 5-formyl-2'-deoxyuridine ethylene acetal (4b), and 5-formyl-2'-deoxyuridine propylene acetal (5b). These were evaluated in human foreskin fibroblast cells challenged with the vaccinia virus or cowpox virus. Of the four gem diether nucleosides, only the dimethyl gem diether congener showed significant antiviral activity against both viruses. This antiviral activity did not appear to be related to the decomposition to the 5-formyl-2'-deoxyuridine, which was itself devoid of anti-orthopoxvirus activity in these assays. Moreover, at the pH of the in vitro assays, 2b was very stable with a decomposition (to aldehyde) half-life of >15 d. The anti-orthopoxvirus activity of pyrimidine may be favored by the introduction of hydrophilic moieties to the 5-position side chain.
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Affiliation(s)
| | | | | | | | | | - Paul F. Torrence
- To whom correspondence should be addressed. Tel: (928) 523-0298. Fax: (928) 523-8111.
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22
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Prichard MN, Keith KA, Quenelle DC, Kern ER. Activity and mechanism of action of N-methanocarbathymidine against herpesvirus and orthopoxvirus infections. Antimicrob Agents Chemother 2006; 50:1336-41. [PMID: 16569849 PMCID: PMC1426929 DOI: 10.1128/aac.50.4.1336-1341.2006] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
N-Methanocarbathymidine [(N)-MCT] is a conformationally locked nucleoside analog that is active against some herpesviruses and orthopoxviruses in vitro. The antiviral activity of this molecule is dependent on the type I thymidine kinase (TK) in herpes simplex virus and also appears to be dependent on the type II TK expressed by cowpox and vaccinia viruses, suggesting that it is a substrate for both of these divergent forms of the enzyme. The drug is also a good inhibitor of viral DNA synthesis in both viruses and is consistent with inhibition of the viral DNA polymerase once it is activated by the viral TK homologs. This mechanism of action explains the rather unusual spectrum of activity, which is limited to orthopoxviruses, alphaherpesviruses, and Epstein-Barr virus, since these viruses express molecules with TK activity that can phosphorylate and thus activate the drug. The compound is also effective in vivo and reduces the mortality of mice infected with orthopoxviruses, as well as those infected with herpes simplex virus type 1 when treatment is initiated 24 h after infection. These results indicate that (N)-MCT is active in vitro and in vivo, and its mechanism of action suggests that the molecule may be an effective therapeutic for orthopoxvirus and herpesvirus infections, thus warranting further development.
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Affiliation(s)
- Mark N Prichard
- Department of Pediatrics, University of Alabama School of Medicine, Birmingham, AL 35233, USA.
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23
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Fan X, Zhang X, Zhou L, Keith KA, Kern ER, Torrence PF. A pyrimidine–pyrazolone nucleoside chimera with potent in vitro anti-orthopoxvirus activity. Bioorg Med Chem Lett 2006; 16:3224-8. [PMID: 16603351 DOI: 10.1016/j.bmcl.2006.03.043] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2006] [Revised: 03/13/2006] [Accepted: 03/14/2006] [Indexed: 11/30/2022]
Abstract
Synthetic hybridization of two privileged drug scaffolds, pyrazolone on the one hand and pyrimidine nucleoside on the other, resulted in the generation of two novel 5-substituted pyrimidine nucleosides with potent in vitro antiviral activity against two representative orthopoxviruses, vaccinia virus and cowpox virus.
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Affiliation(s)
- Xuesen Fan
- Department of Chemistry and Biochemistry, Northern Arizona University, Flagstaff, AZ 86011, USA
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24
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Quenelle DC, Keith KA, Kern ER. In vitro and in vivo evaluation of isatin-beta-thiosemicarbazone and marboran against vaccinia and cowpox virus infections. Antiviral Res 2006; 71:24-30. [PMID: 16621041 DOI: 10.1016/j.antiviral.2006.02.010] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2005] [Revised: 01/25/2006] [Accepted: 02/22/2006] [Indexed: 11/18/2022]
Abstract
It has been reported previously that some thiosemicarbazone compounds have prophylactic activity against smallpox disease and therapeutic activity against vaccinia virus (VV) infections. In these studies, isatin-beta-thiosemicarbazone (IBT) and marboran were administered once daily by intraperitoneal (ip) injection to mice using 30, 10 or 3 mg/kg for 5 days beginning 24, 48 or 72 h after inoculation with VV or cowpox virus (CV). Both compounds were highly effective (p < 0.01) at preventing mortality due to VV even when treatment was delayed up to 72 h postinfection. In CV-infected mice, neither IBT nor Marboran were effective in preventing mortality at any dosage tested when administered at 24 h postinoculation. Viral replication in liver, spleen and kidney was delayed or reduced by 100-to 10,000-fold by 10 mg/kg of marboran, but not IBT, in VV infections. Neither compound was effective against CV infection. Neither IBT nor marboran treatment of mice cutaneously infected with VV or CV reduced viral replication or clinical disease. These results suggest that this class of compound has little therapeutic potential for orthopoxvirus infections since the in vivo activity against CV, a surrogate virus for variola, is lacking.
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25
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Prichard MN, Williams AD, Keith KA, Harden EA, Kern ER. Distinct thymidine kinases encoded by cowpox virus and herpes simplex virus contribute significantly to the differential antiviral activity of nucleoside analogs. Antiviral Res 2006; 71:1-6. [PMID: 16530858 DOI: 10.1016/j.antiviral.2006.01.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Revised: 01/19/2006] [Accepted: 01/19/2006] [Indexed: 11/21/2022]
Abstract
Orthopoxviruses and herpesviruses are both large enveloped DNA viruses, yet these virus families exhibit very different susceptibilities to antiviral drugs. We investigated the activation of nucleoside analogs by the types I and II thymidine kinase (TK) homologs expressed by herpes simplex virus type 1 (HSV-1) and cowpox virus (CV). Antiviral activity against TK(-) and TK(+) strains of HSV-1 and CV was determined, and the ratio of the EC(50) values was used as a measurement of TK dependence. As to HSV-1, most of the selected compounds were markedly less effective against the TK(-) strains, suggesting that this enzyme was required for the activation of these nucleoside analogs. This differs from the results for CV where only idoxuridine and bromodeoxyuridine appeared to be activated, putatively by the type II TK expressed by this virus. These data confirm that the type II TK encoded by CV exhibits a more limited substrate specificity than the type I TK encoded by HSV-1. These data suggest that the inefficient activation of nucleoside analogs by the orthopoxvirus TK significantly limits their activity. Additional screening against orthopoxviruses will be required to identify nucleoside analogs that are efficiently activated by their type II TK.
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Affiliation(s)
- Mark N Prichard
- University of Alabama School of Medicine, Department of Pediatrics, Birmingham, 35233, USA.
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26
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Beadle JR, Wan WB, Ciesla SL, Keith KA, Hartline C, Kern ER, Hostetler KY. Synthesis and Antiviral Evaluation of Alkoxyalkyl Derivatives of 9-(S)-(3-Hydroxy-2-phosphonomethoxypropyl)adenine against Cytomegalovirus and Orthopoxviruses. J Med Chem 2006; 49:2010-5. [PMID: 16539388 DOI: 10.1021/jm050473m] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
9-(S)-(3-Hydroxy-2-phosphonomethoxypropyl)adenine [(S)-HPMPA] was one of the first acyclic nucleoside phosphonates described and has been reported to have good antiviral activity against most double-stranded DNA viruses, including the herpes group viruses and the orthopoxviruses. However, (S)-HPMPA is not orally bioavailable and has not been developed for clinical use. We have prepared orally bioavailable lipid esters of (S)-HPMPA and report their synthesis and antiviral evaluation against cytomegalovirus and orthopoxviruses. These esters were evaluated in vitro in cells infected with human cytomegalovirus (HCMV), murine cytomegalovirus (MCMV), vaccinia (VV), and cowpox viruses (CV). The most active compound, oleyloxyethyl-(S)-HPMPA, was found to have EC50 value of 0.003 microM against HCMV vs 1.4 microM for unmodified HPMPA. In cells infected with VV and CV, octadecyloxyethyl-(S)-HPMPA had EC50 values of 0.01-0.02 microM versus 2.7-4.0 microM for unmodified HPMPA. When compared with the alkoxyalkyl esters of cidofovir, the corresponding alkoxyalkyl esters of (S)-HPMPA were equally active against HCMV and MCMV but were 15-20-fold more active against VV and CV in vitro. The alkoxyalkyl esters of (S)-HPMPA are promising new compounds worthy of further investigation for treatment of infections caused by herpes viruses and orthopoxviruses.
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Affiliation(s)
- James R Beadle
- Department of Medicine, VA San Diego Healthcare System and the University of California, San Diego, La Jolla, California 92093-0676, USA
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Roy A, Schneller SW, Keith KA, Hartline CB, Kern ER. The 4',4'-difluoro analog of 5'-noraristeromycin: a new structural prototype for possible antiviral drug development toward orthopoxvirus and cytomegalovirus. Bioorg Med Chem 2005; 13:4443-9. [PMID: 15908221 DOI: 10.1016/j.bmc.2005.04.044] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Revised: 04/18/2005] [Accepted: 04/18/2005] [Indexed: 11/23/2022]
Abstract
As a surrogate for 4'-hydroxy-5'-noraristeromycin and related carbocyclic nucleosides, an efficient, enantiodivergent synthetic route to both enantiomers of 5-(6-amino-9H-purin-9-yl)-3,3-difluorocyclopentane-1,2-diol (6 and ent-6) has been developed from a common starting material ((+)-(1R,4S)-4-hydroxy-2-cyclopenten-1-yl acetate, 10). Both compounds were assayed versus a series of viruses. The only response found was for compound 6 toward vaccinia and cowpox (EC50 of 143 and 94 microM, respectively) and human cytomegalovirus (EC50 of 6.2 microM). Both compounds were non-cytotoxic. While not as active as cidofovir toward the orthopox viruses and ganciclovir toward cytomegalovirus, compound 6 offers a new structural prototype upon which to build for uncovering new agents effective against these viral types.
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Affiliation(s)
- Atanu Roy
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849, USA
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Abstract
Novel strategies are required to combat pox virus infections, whether caused by escape of viruses such as monkeypox from indigenous areas or intentional release of smallpox. Anti-smallpox drugs with a unique mode of antiviral action, inhibition of transcription termination, were known but not therapeutically useful. Using a combinatorial method, variants of the basic isatin-beta-thiosemicarbazone structure were prepared and examined for cytotoxicity and antiviral activity in vaccinia virus- and cowpox virus-infected human cells. Potent and much more selective N-aminomethyl-isatin-beta-thiosemicarbazones were discovered.
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Affiliation(s)
- Michael C Pirrung
- Department of Chemistry, Levine Science Research Center, Box 90317, Duke University, Durham, North Carolina 27708-0317, USA.
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Keith KA, Wan WB, Ciesla SL, Beadle JR, Hostetler KY, Kern ER. Inhibitory activity of alkoxyalkyl and alkyl esters of cidofovir and cyclic cidofovir against orthopoxvirus replication in vitro. Antimicrob Agents Chemother 2004; 48:1869-71. [PMID: 15105146 PMCID: PMC400568 DOI: 10.1128/aac.48.5.1869-1871.2004] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A new series of ether lipid esters of cidofovir (CDV) were evaluated against vaccinia and cowpox viruses. Activity was dependent on number of atoms in the alkyl or alkoxyalkyl chain, the linker moiety, and the presence of a double bond in the alkoxyalkyl chains linked to the phosphonate moiety of CDV.
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Affiliation(s)
- Kathy A Keith
- University of Alabama School of Medicine, Birmingham, Alabama 35233, USA
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Keith KA, Hitchcock MJM, Lee WA, Holý A, Kern ER. Evaluation of nucleoside phosphonates and their analogs and prodrugs for inhibition of orthopoxvirus replication. Antimicrob Agents Chemother 2003; 47:2193-8. [PMID: 12821467 PMCID: PMC161877 DOI: 10.1128/aac.47.7.2193-2198.2003] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In the event of a bioterrorism attack using smallpox virus, there currently is no approved drug for the treatment of infections with this virus. We have reported previously that (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]cytosine (HPMPC) (also known as cidofovir [CDV]) has good activity against poxvirus infections; however, a major limitation is the requirement for intravenous administration. Two related acyclic nucleoside phosphonates (ANPs), adefovir (PMEA) and tenofovir (PMPA), are active against human immunodeficiency virus or hepatitis B virus but do not have activity against the orthopoxviruses. Therefore, we have evaluated a number of analogs and potential oral prodrugs of these three compounds for their ability to inhibit the replication of vaccinia virus or cowpox virus in tissue culture cells. The most-active compounds within the CDV series were (S)-HPMPA and (butyl L-alaninyl) cyclic HPMPC, with 50% effective concentrations (EC(50)s) from 4 to 8 microM, compared with 33 to 43 microM for CDV. Although PMEA itself was not active, adefovir dipivoxil [bis[(pivaloyl)oxymethyl] PMEA] and bis(butyl L-alaninyl) PMEA were active against both viruses, and bis(butyl L-alaninyl) PME-N6-(cyclopropyl)DAP and (isopropyl L-alaninyl)phenyl PME-N6-(cyclopropyl)DAP were the most active compounds tested, with EC(50)s of 0.1 to 2.6 microM. In the PMPA series, none of the analogs tested had significantly better activity than PMPA itself. These data indicate that a number of these ANP derivatives have activity against vaccinia virus and cowpox virus in vitro and should be evaluated for their efficacies in animal models.
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Affiliation(s)
- Kathy A Keith
- University of Alabama School of Medicine, Birmingham, Alabama 35233, USA.
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Lewenson SB, Keith KA, Kelleher C, Polansky E. Carrying on the legacy of Lillian Wald. Partnership with the Henry Street Settlement and the Lienhard School of Nursing at Pace University. Nurs Leadersh Forum 2002; 5:116-21. [PMID: 12004649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
The Lienhard School of Nursing (LSN) at Pace University and the Henry Street Settlement (HSS) developed a partnership to bring nursing back to the HSS founded by nursing leader, Lillian Wald. Through this partnership HSS and LSN faculty and students explored how they could accomplish the goal of providing nursing care to a diverse urban population. Struggles to understand the community and the role of nursing in this kind of setting provided students with unique and complex community and leadership experiences. Students learned not only from the nursing care they provided but also from the behaviors of the stakeholders in the partnership. The partnership has provided an ongoing opportunity for continuing the legacy of Lillian Wald.
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Affiliation(s)
- S B Lewenson
- Pace University, Lienhard School of Nursing, 861 Bedford Road, Pleasantville, NY 10570, USA
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Keith KA. Infant feeding choice among first-time mothers. Res Theory Nurs Pract 1998; 11:199-224; discussion 225-9. [PMID: 9481181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The choice of an infant feeding method is a poorly understood phenomenon. In all societies women are the infant feeders, regardless of the method of infant feeding. How women decide on an infant feeding method is not known; the decision making is complex and frequently unconscious. A qualitative study using the methods of grounded theory was undertaken to understand how women make an infant feeding decision. Eight women were interviewed; 14 themes were identified through the analysis of interview transcripts, field notes, researcher memos, and related literature. The themes were distilled into six conceptual categories which were used as a basis for a model: Conceptualization of the Decision-Making Process in Infant Feeding.
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Affiliation(s)
- K A Keith
- Department of Graduate Studies, Lienhard School of Nursing, Pace University, Pleasantville, NY 10570, USA
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Quenelle DC, Keith KA, Dunleavy KE, Taylor BA, Bowdon BJ, Brazier AD, Mullon CJ, Allen LB. Evaluation of anti-AIDS drugs in conventional mice implanted with a permeable membrane device containing human T cells infected with HIV. Antiviral Res 1997; 35:123-9. [PMID: 9217249 DOI: 10.1016/s0166-3542(97)00014-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We now report the confirmation of the work of Hollingshead et al. (1995) on development of a cell based hollow fiber (HF) system for evaluating potential anti-AIDS drugs in vivo using conventional mice rather than SCID mice. CD4 +, CEM-SS cells infected with HIV/1, strain RF, at a multiplicity of infection of 0.1 were placed into HFs. The fibers were implanted into the peritoneal cavity of outbred Swiss mice. Using this model, the antiviral activity of azidothymidine (AZT) at doses of approximately 150, 75 and 37.5 mg/kg/day was evaluated by administering AZT to the mice in drinking water. Upon fiber removal on day 6, AZT treatment was shown to significantly increase CEM cell viability over the untreated, virus control group and significantly reduced the levels of HIV p24 and HIV RT activity.
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Affiliation(s)
- D C Quenelle
- Life Sciences Division, Southern Research Institute, Lexington, MA 02173, USA
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Vince R, Kilama J, Pham PT, Beers SA, Bowdon BJ, Keith KA, Parker WB. 6-Substituted Derivatives of Carbovir: Anti-HIV Activity. ACTA ACUST UNITED AC 1995. [DOI: 10.1080/15257779508009751] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
Synthetic peptides described as dog renin inhibitors were found to effectively inhibit the aspartyl protease of human immunodeficiency virus (HIV). The selection of oligopeptides for the HIV protease inhibition study was based on 1) the current strategy of inhibiting aspartyl proteases with transition state analogs, and 2) our previous observations regarding optimal structural differentiation at the P2 position among human, dog, and rat renin inhibitors. In an in vitro assay system consisting of recombinant HIV protease and a synthetic decapeptide substrate (at pH 5.5), results show that HIV protease was unaffected by statine-containing analogs carrying histidine at the P2 position whereas analogs containing valine at the same position yielded anti-protease IC50 values ranging from 50 to 500 nM. As anticipated, some analogs were also shown to inhibit processing of recombinant polyprotein substrate by HIV protease in vitro. The anti-viral activity of three inhibitors was studied in HIV-infected CEM and MT-2 cells. Results showed that one compound, Ac-Naphthylalanyl-Pro-Phe-Val-Statine-Leu-Phe-NH2 (antiprotease IC50 value = 0.4 microM), protected the infected cells effectively with IC50 values (0.73 microM for CEM cells and 0.88 microM for MT-2 cells). This antiviral effect is comparable to those obtained with AZT and ddC in parallel studies of MT-2 cells.
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Affiliation(s)
- K Y Hui
- Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, Indiana 46285
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Abstract
In this study we have shown that NHS-biotin and I125-streptavidin can detect cuticular polypeptides of Ostertagia spp. The labelled polypeptide profile of intact nematodes is simple compared to the profile obtained by labelling homogenates. None of the major internal polypeptides are labelled and the subset of proteins labelled in intact nematodes appears to be mainly surface associated. The results presented here demonstrate that NHS-biotin may be used as a reagent for the analysis of surface polypeptides. The surface polypeptide profiles of the five major developmental stages (L1, L2, L3, L4 and adult) of Ostertagia circumcincta show a series of stage-specific molecules with no polypeptides common to all stages, indicating that the cuticle is a dynamic structure which changes throughout the life cycle. Similarily comparison of Ostertagia ostertagi L3 and L4 stage surface profiles showed that each stage is clearly distinct; comparison of these stages between the two species shows an overall similarity.
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Affiliation(s)
- K A Keith
- Wellcome Unit of Molecular Parasitology, University of Glasgow, U.K
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Abstract
Twelve cultivars of rice (Oryza sativa L.), representing deepwater, short-statured, and semidwarf types, were tested for their response to submergence. The magnitude of the response varied between cultivars; however, all cultivars responded to submergence by rapid growth once internodal elongation had started. Three of these cultivars were tested for elongation capacity at four ages. The deepwater rice was capable of rapid internodal elongation in response to submergence at 4 weeks of age. Growth of the short-statured and semidwarf cultivars was not stimulated by submergence until about 10 weeks of age. In air, the internodes of deepwater rice grew slower than did those of the short-statured and semidwarf cultivars. We also investigated the elongation response of stem sections of all 12 cultivars to an atmosphere containing 3% O(2), 6% CO(2), 91% N(2) (all by volume), and 1 microliter per liter ethylene. We found that the response of each of the non-deepwater cultivars was qualitatively and quantitatively similar to that of the deepwater rice.
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Affiliation(s)
- K A Keith
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
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