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Yang N, Wang J, Wang ZW, Wang QH, Yang HG, Wang XJ, Cheng MS. Computational insights into the inhibition of inosine 5'-monophosphate dehydrogenase by mycophenolic acid analogs: three-dimensional quantitative structure-activity relationship and molecular docking studies. Chem Biol Drug Des 2012; 79:1063-71. [PMID: 22405057 DOI: 10.1111/j.1747-0285.2012.01375.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Inosine 5'-monophosphate dehydrogenase (IMPDH) is a key enzyme in the de novo synthesis of guanosine nucleotides. It is considered as an important target in the quest for drugs in the immunosuppressive, antiviral, antibacterial, and anticancer therapeutic areas. Herein, we report the 3D-QSAR analyses using comparative molecular field analysis (CoMFA), comparative molecular similarity indices analysis (CoMSIA) and docking on mycophenolic acid derivates for the first time. We obtained cross-validated q(2) value of 0.805 for CoMFA and 0.620 for CoMSIA, while the non-cross-validated r(2) values for them were 0.969 and 0.935, respectively. Based on the CoMFA and CoMSIA contour maps and docking analyses, some key structural factors responsible for inhibitory activity were revealed. The results obtained from this study could be used for the rational design of potent inhibitors against IMPDH.
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52
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Yang N, Wang QH, Wang WQ, Wang J, Li F, Tan SP, Cheng MS. The design, synthesis and in vitro immunosuppressive evaluation of novel isobenzofuran derivatives. Bioorg Med Chem Lett 2011; 22:53-6. [PMID: 22172700 DOI: 10.1016/j.bmcl.2011.11.078] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 10/21/2011] [Accepted: 11/19/2011] [Indexed: 11/27/2022]
Abstract
The synthesis and biological evaluation of a series of novel isobenzofuran-based compounds are described. The compounds were evaluated for their immunosuppressive effects of T-cell proliferation and IMPDH type II inhibitor activity in vitro, as well as their structure-activity relationships were assessed. Several compounds demonstrated highly efficacious immunosuppressive properties, especially compounds 2d, 2e, 2h and 2j, which were superior to MPA, while compounds 2k, 2m, 2n, 4c and 5d exhibited an equipotent inhibitory activity compared to MPA. Generally, it was obviously demonstrated that α,β-unsaturated amides proved more potent than the diamide and urea series. The present study provides a guide for further research on development of safe and effective immunosuppressive agents.
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Affiliation(s)
- Na Yang
- Key Laboratory of Structure-Based Drugs Design & Discovery of Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, PR China
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53
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Sepúlveda CS, García CC, Fascio ML, D'Accorso NB, Docampo Palacios ML, Pellón RF, Damonte EB. Inhibition of Junin virus RNA synthesis by an antiviral acridone derivative. Antiviral Res 2011; 93:16-22. [PMID: 22027649 DOI: 10.1016/j.antiviral.2011.10.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 09/06/2011] [Accepted: 10/07/2011] [Indexed: 01/31/2023]
Abstract
There are no specific approved drugs for the treatment of agents of viral hemorrhagic fevers (HF) and antiviral therapies against these viruses are urgently needed. The present study characterizes the potent and selective antiviral activity against the HF causing arenavirus Junin virus (JUNV) of the compound 10-allyl-6-chloro-4-methoxy-9(10H)-acridone, designated 3f. The effectiveness of 3f to inhibit JUNV multiplication was not importantly affected by the initial multiplicity of infection, with similar effective concentration 50% (EC(50)) values in virus yield inhibition assays performed in Vero cells in the range of 0.2-40 plaque forming units (PFU)/cell. Mechanistic studies demonstrated that 3f did not affect the initial steps of adsorption and internalization. The subsequent process of viral RNA synthesis was strongly inhibited, as quantified by real time RT-PCR in compound-treated cells relative to non-treated cells. The addition of exogenous guanosine rescued the infectivity and RNA synthesis of JUNV in 3f-treated cells in a dose-dependent manner, but the reversal was partial, suggesting that the reduction of the GTP pool contributed to the antiviral activity of 3f, but it was not the main operative mechanism. The comparison of 3f with two other viral RNA inhibitors, ribavirin and mycophenolic acid, showed that ribavirin did not act against JUNV through the cellular enzyme inosine monophosphate dehydrogenase (IMPDH) inhibition whereas the anti-JUNV activity of mycophenolic acid was mainly targeted at this enzyme.
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Affiliation(s)
- Claudia S Sepúlveda
- Laboratorio de Virología, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, Piso 4, 1428 Buenos Aires, Argentina
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Hedstrom L, Liechti G, Goldberg JB, Gollapalli DR. The antibiotic potential of prokaryotic IMP dehydrogenase inhibitors. Curr Med Chem 2011; 18:1909-18. [PMID: 21517780 DOI: 10.2174/092986711795590129] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Accepted: 04/04/2011] [Indexed: 12/30/2022]
Abstract
Inosine 5'-monophosphate dehydrogenase (IMPDH) catalyzes the first committed step of guanosine 5'-monophosphate (GMP) biosynthesis, and thus regulates the guanine nucleotide pool, which in turn governs proliferation. Human IMPDHs are validated targets for immunosuppressive, antiviral and anticancer drugs, but as yet microbial IMPDHs have not been exploited in antimicrobial chemotherapy. Selective inhibitors of IMPDH from Cryptosporidium parvum have recently been discovered that display anti-parasitic activity in cell culture models of infection. X-ray crystal structure and mutagenesis experiments identified the structural features that determine inhibitor susceptibility. These features are found in IMPDHs from a wide variety of pathogenic bacteria, including select agents and multiply drug resistant strains. A second generation inhibitor displays antibacterial activity against Helicobacter pylori, demonstrating the antibiotic potential of IMPDH inhibitors.
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Affiliation(s)
- L Hedstrom
- Brandeis University, Departments of Biology, Waltham, MA 02454-9110, USA.
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55
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Ranjith-Kumar CT, Wen Y, Baxter N, Bhardwaj K, Cheng Kao C. A cell-based assay for RNA synthesis by the HCV polymerase reveals new insights on mechanism of polymerase inhibitors and modulation by NS5A. PLoS One 2011; 6:e22575. [PMID: 21799903 PMCID: PMC3142182 DOI: 10.1371/journal.pone.0022575] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 06/24/2011] [Indexed: 12/24/2022] Open
Abstract
RNA synthesis by the genotype 1b hepatitis C virus (HCV) polymerase (NS5B) transiently expressed in Human embryonic kidney 293T cells or liver hepatocytes was found to robustly stimulate RIG-I-dependent luciferase production from the interferon β promoter in the absence of exogenously provided ligand. This cell-based assay, henceforth named the 5BR assay, could be used to examine HCV polymerase activity in the absence of other HCV proteins. Mutations that decreased de novo initiated RNA synthesis in biochemical assays decreased activation of RIG-I signaling. In addition, NS5B that lacks the C-terminal transmembrane helix but remains competent for RNA synthesis could activate RIG-I signaling. The addition of cyclosporine A to the cells reduced luciferase levels without affecting agonist-induced RIG-I signaling. Furthermore, non-nucleoside inhibitor benzothiadiazines (BTDs) that bind within the template channel of the 1b NS5B were found to inhibit the readout from the 5BR assay. Mutation M414T in NS5B that rendered the HCV replicon resistant to BTD was also resistant to BTDs in the 5BR assay. Co-expression of the HCV NS5A protein along with NS5B and RIG-I was found to inhibit the readout from the 5BR assay. The inhibition by NS5A was decreased with the removal of the transmembrane helix in NS5B. Lastly, NS5B from all six major HCV genotypes showed robust activation of RIG-I in the 5BR assay. In summary, the 5BR assay could be used to validate inhibitors of the HCV polymerase as well as to elucidate requirements for HCV-dependent RNA synthesis.
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Affiliation(s)
- C. T. Ranjith-Kumar
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana, United States of America
| | - Yahong Wen
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana, United States of America
| | - Nielson Baxter
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana, United States of America
| | - Kanchan Bhardwaj
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana, United States of America
| | - C. Cheng Kao
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana, United States of America
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56
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Yang N, Wang J, Li J, Wang QH, Wang Y, Cheng MS. A three-dimensional pharmacophore model for IMPDH inhibitors. Chem Biol Drug Des 2011; 78:175-82. [PMID: 21507206 DOI: 10.1111/j.1747-0285.2011.01128.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Inosine 5'-monophosphate dehydrogenase (IMPDH) is a key enzyme in the de novo synthesis of guanosine nucleotides. It is considered an important target in the quest for drugs in the immunosuppressive, antiviral, antibacterial and anticancer therapeutic areas. In this study, a chemical feature-based pharmacophore model of IMPDH inhibitors has been firstly developed with the aid of the HypoRefine protocol within Discovery Studio 2.5. The best model for IMPDH inhibitors, Hypo1-1, was characterized by the best correlation coefficient (0.97595) and the lowest RMSD (0.582058). It consisted of one hydrogen-bond donor, one hydrogen-bond acceptor, one aromatic ring and one hydrophobic feature, as well as two excluded volumes. The model was validated using a wide range of test molecules and a cross-validation. Furthermore, the pharmacophore features were confirmed by molecular docking studies. The pharmacophore model could quantitatively predict inhibitor activity and identify highly potent molecules. Therefore, the present results could be valuable for the discovery and development of specific IMPDH inhibitors.
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Affiliation(s)
- Na Yang
- Key Laboratory of Structure-Based Drugs Design and Discovery of Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang, China
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57
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Host-based ribavirin resistance influences hepatitis C virus replication and treatment response. J Virol 2011; 85:7273-83. [PMID: 21543469 DOI: 10.1128/jvi.00629-11] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Many individuals infected with hepatitis C virus (HCV) develop a chronic infection, and of those who are treated with pegylated interferon and ribavirin (RBV), many do not respond. While the nucleoside analog RBV improves treatment outcome, and will likely be an important component of therapy with next-generation viral inhibitors, RBV's mechanism is controversial. Most of RBV's proposed mechanisms require RBV import into cells. Therefore, we explored whether host-based RBV resistance develops through reduced cellular uptake, akin to chemotherapy resistance in some cancers. We examined the effect of host-based RBV resistance on HCV replication in cultured hepatoma Huh7.5 liver cells and whether RBV resistance develops in HCV patients. When Huh7.5 cells were exposed to RBV, resistance developed through reduced RBV uptake via the ENT1 nucleoside transporter and antiviral efficacy was reduced. The uptake defect in RBV-resistant cells was specific to RBV, since transport of another ENT1 substrate, cytidine, was unaffected. Importantly, RBV uptake significantly declined in HCV patient peripheral blood mononuclear cells (PBMCs) following 4 weeks of therapy. Furthermore, maintenance of RBV uptake correlated with rapid treatment response. Our results uncovered a novel form of antiviral drug resistance and suggest that host-based RBV resistance develops in HCV patients undergoing therapy and that maintenance of RBV uptake may contribute to rapid viral clearance.
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58
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Toubiana J, Rossi AL, Grimaldi D, Belaidouni N, Chafey P, Clary G, Courtine E, Pene F, Mira JP, Claessens YE, Chiche JD. IMPDHII protein inhibits Toll-like receptor 2-mediated activation of NF-kappaB. J Biol Chem 2011; 286:23319-33. [PMID: 21460227 DOI: 10.1074/jbc.m110.201210] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Toll-like receptor 2 (TLR2) plays an essential role in innate immunity by the recognition of a large variety of pathogen-associated molecular patterns. It induces its recruitment to lipid rafts induces the formation of a membranous activation cluster necessary to enhance, amplify, and control downstream signaling. However, the exact composition of the TLR2-mediated molecular complex is unknown. We performed a proteomic analysis in lipopeptide-stimulated THP1 and found IMPDHII protein rapidly recruited to lipid raft. Whereas IMPDHII is essential for lymphocyte proliferation, its biologic function within innate immune signal pathways has not been established yet. We report here that IMPDHII plays an important role in the negative regulation of TLR2 signaling by modulating PI3K activity. Indeed, IMPDHII increases the phosphatase activity of SHP1, which participates to the inactivation of PI3K.
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59
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Intracellular GTP level determines cell's fate toward differentiation and apoptosis. Toxicol Appl Pharmacol 2011; 253:188-96. [PMID: 21396949 DOI: 10.1016/j.taap.2011.02.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 02/09/2011] [Accepted: 02/28/2011] [Indexed: 01/23/2023]
Abstract
Since the adequate supply of guanine nucleotides is vital for cellular activities, limitation of their syntheses would certainly result in modulation of cellular fate toward differentiation and apoptosis. The aim of this study was to set a correlation between the intracellular level of GTP and the induction of relevant signaling pathways involved in the cell's fate toward life or death. In that regard, we measured the GTP level among human leukemia K562 cells exposed to mycophenolic acid (MPA) or 3-hydrogenkwadaphnin (3-HK) as two potent inosine monophosphate dehydrogenase inhibitors. Our results supported the maturation of the cells when the intracellular GTP level was reduced by almost 30-40%. Under these conditions, 3-HK and/or MPA caused up-regulation of PKCα and PI3K/AKT pathways. Furthermore, co-treatment of cells with hypoxanthine plus 3-HK or MPA, which caused a reduction of about 60% in the intracellular GTP levels, led to apoptosis and activation of mitochondrial pathways through inverse regulation of Bcl-2/Bax expression and activation of caspase-3. Moreover, our results demonstrated that attenuation of GTP by almost 60% augmented the intracellular ROS and nuclear localization of p21 and subsequently led to cell death. These results suggest that two different threshold levels of GTP are needed for induction of differentiation and/or ROS-associated apoptosis.
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60
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Gollapalli DR, Macpherson IS, Liechti G, Gorla SK, Goldberg JB, Hedstrom L. Structural determinants of inhibitor selectivity in prokaryotic IMP dehydrogenases. ACTA ACUST UNITED AC 2011; 17:1084-91. [PMID: 21035731 DOI: 10.1016/j.chembiol.2010.07.014] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2010] [Revised: 06/26/2010] [Accepted: 07/20/2010] [Indexed: 10/18/2022]
Abstract
The protozoan parasite Cryptosporidium parvum is a major cause of gastrointestinal disease; no effective drug therapy exists to treat this infection. Curiously, C. parvum IMPDH (CpIMPDH) is most closely related to prokaryotic IMPDHs, suggesting that the parasite obtained its IMPDH gene via horizontal transfer. We previously identified inhibitors of CpIMPDH that do not inhibit human IMPDHs. Here, we show that these compounds also inhibit IMPDHs from Helicobacter pylori, Borrelia burgdorferi, and Streptococcus pyogenes, but not from Escherichia coli. Residues Ala165 and Tyr358 comprise a structural motif that defines susceptible enzymes. Importantly, a second-generation CpIMPDH inhibitor has bacteriocidal activity on H. pylori but not E. coli. We propose that CpIMPDH-targeted inhibitors can be developed into a new class of antibiotics that will spare some commensal bacteria.
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61
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Nakanishi T, Morokata T, Noto T, Kubo K, Umeno H, Kinugasa F, Eikyu Y, Kozuki Y, Seki N. Effect of the inosine 5'-monophosphate dehydrogenase inhibitor BMS-566419 on renal fibrosis in unilateral ureteral obstruction in rats. Int Immunopharmacol 2010; 10:1434-9. [PMID: 20832515 DOI: 10.1016/j.intimp.2010.08.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Revised: 08/12/2010] [Accepted: 08/18/2010] [Indexed: 02/07/2023]
Abstract
Chronic allograft nephropathy (CAN) is a major cause of late allograft loss. One morphological characteristic of CAN is renal interstitial fibrosis. Mycophenolate mofetil (MMF), the inosine 5'-monophosphate dehydrogenase (IMPDH) inhibitor, has been reported to attenuate the progression of renal interstitial fibrosis. However, the question of whether the newly synthesized IMPDH inhibitors with structures different from MMF have an antifibrotic effect remains unanswered. We evaluated the antifibrotic effects of BMS-566419, a chemically synthesized IMPDH inhibitor, using an experimental rat model, unilateral ureteral obstruction (UUO), in comparison with those of MMF. Expression levels of monocyte chemoattractant protein-1 (MCP-1) and transforming growth factor-beta1 (TGF-β1), which play important roles in UUO-induced renal fibrosis, were also investigated to determine the mechanism by which BMS-566419 affects the progression of renal fibrosis. After 14 days of UUO, interstitial fibrosis was frequently observed in the renal cortex of rats administered vehicle control. BMS-566419 by oral administration showed a significant and dose-dependent suppressive effect on UUO-induced renal fibrosis in histopathological experiments. BMS-566419 treatment also decreased collagen content, as indicated by hydroxyproline concentration, and the expression of collagen type 1 mRNA. BMS-566419 also decreased the expression of mRNA for both MCP-1 and TGF-β1. The antifibrotic effects of treatment with BMS-566419 at 60 mg/kg seemed comparable to those with MMF at 40 mg/kg. These results suggest that BMS-566419 and other chemically synthesized IMPDH inhibitors have beneficial pharmacological effects similar to those of MMF, and are potential pharmaceutical candidates in the treatment of fibrotic renal disease, including CAN.
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Affiliation(s)
- Tomonori Nakanishi
- Pharmacology Research Laboratories, Astellas Pharma Inc., Tsukuba-shi, Ibaraki, Japan.
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62
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Chen L, Petrelli R, Gao G, Wilson DJ, McLean GT, Jayaram HN, Sham YY, Pankiewicz KW. Dual inhibitors of inosine monophosphate dehydrogenase and histone deacetylase based on a cinnamic hydroxamic acid core structure. Bioorg Med Chem 2010; 18:5950-64. [PMID: 20650640 DOI: 10.1016/j.bmc.2010.06.081] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Revised: 06/19/2010] [Accepted: 06/23/2010] [Indexed: 11/17/2022]
Abstract
Small molecules that act on multiple biological targets have been proposed to combat the drug resistance commonly observed for cancer chemotherapy. By combining the structural features of known inhibitors of inosine monophosphate dehydrogense (IMPDH) and histone deacetylase (HDAC), dual inhibitors of IMPDH and HDAC based on the scaffold of cinnamic hydroxamic acid (CHA) have been designed, synthesized, and evaluated in biological assays. Key features, including the linker length, linker functionality, substitution position, and interacting groups, have been explored. Their individual contribution to the inhibitory activities against human IMPDH1 and IMPDH2 as well as HDAC has been assessed.
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Affiliation(s)
- Liqiang Chen
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA.
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63
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Jain MK, Zoellner C. Role of ribavirin in HCV treatment response: now and in the future. Expert Opin Pharmacother 2010; 11:673-83. [PMID: 20163278 DOI: 10.1517/14656560903580001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
IMPORTANCE OF THE FIELD Ribavirin is a broad spectrum antiviral agent that is used with pegylated IFN (Peg-IFN) for HCV treatment. Ribavirin does not significantly reduce HCV viral load when used alone but increases rates of sustained virologic response (SVR) when combined with Peg-IFN. HCV genotype 1 infected patients require higher doses of ribavirin administered for a longer duration of time versus HCV genotypes 2 and 3 patients who respond effectively to Peg-IFN with lower doses of ribavirin and shorter duration of therapy. Higher serum concentrations of ribavirin are associated with higher response rates but also higher rates of hemolytic anemia which is a dose limiting side effect. Alternatives to current therapy are under clinical evaluation. AREAS COVERED IN THIS REVIEW Systematic literature review of ribavirin use in HCV patients from 1995 to 2009 was conducted. WHAT THE READER WILL GAIN To review the efficacy and safety of ribavirin in current HCV treatment and in new therapies in Phase III clinical trials. TAKE HOME MESSAGE Ribavirin is a drug which is essential to produce higher SVR rates both with Peg-IFN and HCV protease inhibitors currently in Phase III clinical trials. Thus, ribavirin is and will remain an important drug to achieving higher SVR rates in HCV infected persons.
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Affiliation(s)
- Mamta K Jain
- UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, Texas 75390-9113, USA.
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64
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Macpherson IS, Kirubakaran S, Gorla SK, Riera TV, D'Aquino JA, Zhang M, Cuny GD, Hedstrom L. The structural basis of Cryptosporidium -specific IMP dehydrogenase inhibitor selectivity. J Am Chem Soc 2010; 132:1230-1. [PMID: 20052976 DOI: 10.1021/ja909947a] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Cryptosporidium parvum is a potential biowarfare agent, an important AIDS pathogen, and a major cause of diarrhea and malnutrition. No vaccines or effective drug treatment exist to combat Cryptosporidium infection. This parasite relies on inosine 5'-monophosphate dehydrogenase (IMPDH) to obtain guanine nucleotides, and inhibition of this enzyme blocks parasite proliferation. Here, we report the first crystal structures of CpIMPDH. These structures reveal the structural basis of inhibitor selectivity and suggest a strategy for further optimization. Using this information, we have synthesized low-nanomolar inhibitors that display 10(3) selectivity for the parasite enzyme over human IMPDH2.
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Affiliation(s)
- Iain S Macpherson
- Departments of Biology, Brandeis University, MS009, 415 South Street, Waltham, Massachusetts 02454, USA
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65
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Skibo EB, Jamil A, Austin B, Hansen D, Ghodousi A. Triple molecular target approach to selective melanoma cytotoxicity. Org Biomol Chem 2010; 8:1577-87. [PMID: 20237668 DOI: 10.1039/b920260a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Phenylalanine-linked pyrrolo[1,2-a]benzimidazoles were successfully designed to target melanoma cells in vitro. Our design utilised three molecular targets: a phenylalanine pump, the reducing enzyme DT-diaphorase, and IMP dehydrogenase. We describe the synthesis of these compounds as well as the results of in vitro, in vivo, and QSAR studies.
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Affiliation(s)
- Edward B Skibo
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604, USA.
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66
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Bairagya HR, Mukhopadhyay BP, Sekar K. An insight to the dynamics of conserved water molecular triad in IMPDH II (human): recognition of cofactor and substrate to catalytic Arg 322. J Biomol Struct Dyn 2009; 27:149-58. [PMID: 19583440 DOI: 10.1080/07391102.2009.10507304] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Inosine 5' monophosphate dehydrogenase (IMPDH II) is a key enzyme involved in the de novo biosynthesis pathway of purine nucleotides and is also considered to be an excellent target for cancer inhibitor design. The conserve R 322 residue (in human) is thought to play some role in the recognition of inhibitor and cofactor through the catalytic D 364 and N 303. The 15 ns simulation and the water dynamics of the three different PDB structures (1B3O, 1NF7, and 1NFB) of human IMPDH by CHARMM force field have clearly indicated the involvement of three conserved water molecules (W(L), W(M), and W(C)) in the recognition of catalytic residues (R 322, D 364, and N 303) to inhibitor and cofactor. Both the guanidine nitrogen atoms (NH1 and NH 2) of the R 322 have anchored the di- and mono-nucleotide (cofactor and inhibitor) binding domains via the conserved W(C) and W(L) water molecules. Another conserved water molecule WM seems to bridge the two domains including the R 322 and also the W(C) and W(L) through seven centers H-bonding coordination. The conserved water molecular triad (W(C)-W(M)-W(L)) in the protein complex may thought to play some important role in the recognition of inhibitor and cofactor to the protein through R 322 residue.
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Affiliation(s)
- Hridoy R Bairagya
- Department of Chemistry, National Institute of Technology-Durgapur, West Bengal Durgapur-713209, India
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67
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Effect of the inosine 5'-monophosphate dehydrogenase inhibitor BMS-566419 on rat cardiac allograft rejection. Int Immunopharmacol 2009; 10:91-7. [PMID: 19840872 DOI: 10.1016/j.intimp.2009.09.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 09/15/2009] [Accepted: 09/19/2009] [Indexed: 01/06/2023]
Abstract
Inosine 5'-monophosphate dehydrogenase (IMPDH) inhibition is a critical target in solid organ transplantation, and the development of mycophenolate mofetil (MMF) represents a major advance in transplant medicine. In this study, the in vitro and in vivo pharmacological effects of BMS-566419, a novel chemically synthesized IMPDH inhibitor, were compared to those of mycophenolic acid (MPA) and MMF based on results from several immunological experiments. The in vitro inhibitory activity of BMS-566419 on IMPDH type I/II, immune cell proliferation and antibody production from lipopolysaccharide (LPS)-stimulated B cells was similar, albeit slightly less potent than that of MPA. In a rat heterotopic cardiac transplant model, monotherapy using orally administered BMS-566419 60mg/kg or MMF 40mg/kg prolonged the median survival time (MST) of transplanted grafts in the vehicle group from 5 to 18 and 18.5 days, respectively. In the presence of a sub-therapeutic dose of FK506, BMS-566419 30mg/kg and MMF 20mg/kg showed identical efficacy with an MST of 21.5 days. In dinitrophenol-LPS-stimulated rats in which calcineurin inhibitors failed to inhibit antibody production, in vivo oral administration of BMS-566419 resulted in antibody production suppression with similar efficacy to MMF. The in vivo antibody production against alloantigen was also suppressed by MMF or BMS-566419 treatment. In addition, gastrointestinal toxicity, considered a dose-limiting factor of MMF, was reduced in BMS-566419 treatment. These results suggest that BMS-566419 and other chemically synthesized IMPDH inhibitors have beneficial pharmacological effects similar to those of MMF, and are potential pharmaceutical candidates in transplant indications.
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Abstract
BACKGROUND: Drug discovery is a complex and unpredictable endeavor with a high failure rate. Current trends in the pharmaceutical industry have exasperated these challenges and are contributing to the dramatic decline in productivity observed over the last decade. The industrialization of science by forcing the drug discovery process to adhere to assembly-line protocols is imposing unnecessary restrictions, such as short project time-lines. Recent advances in nuclear magnetic resonance are responding to these self-imposed limitations and are providing opportunities to increase the success rate of drug discovery. OBJECTIVE/METHOD: A review of recent advancements in NMR technology that have the potential of significantly impacting and benefiting the drug discovery process will be presented. These include fast NMR data collection protocols and high-throughput protein structure determination, rapid protein-ligand co-structure determination, lead discovery using fragment-based NMR affinity screens, NMR metabolomics to monitor in vivo efficacy and toxicity for lead compounds, and the identification of new therapeutic targets through the functional annotation of proteins by FAST-NMR. CONCLUSION: NMR is a critical component of the drug discovery process, where the versatility of the technique enables it to continually expand and evolve its role. NMR is expected to maintain this growth over the next decade with advancements in automation, speed of structure calculation, in-cell imaging techniques, and the expansion of NMR amenable targets.
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Affiliation(s)
- Robert Powers
- Department of Chemistry, University of Nebraska Lincoln, Lincoln, NE 68588
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69
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Popsavin M, Spaić S, Svirčev M, Kojić V, Bogdanović G, Pejanović V, Popsavin V. Synthesis of highly cytotoxic tiazofurin mimics bearing a 2,3-anhydro function in the furanose ring. Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.06.100] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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70
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Affiliation(s)
- Lizbeth Hedstrom
- Department of Biology, Brandeis University, MS009, 415 South Street, Waltham, Massachusetts 02454, USA.
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71
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Su H, Gunter JH, de Vries M, Connor T, Wanyonyi S, Newell FS, Segal D, Molero JC, Reizes O, Prins JB, Hutley LJ, Walder K, Whitehead JP. Inhibition of inosine monophosphate dehydrogenase reduces adipogenesis and diet-induced obesity. Biochem Biophys Res Commun 2009; 386:351-5. [PMID: 19523919 DOI: 10.1016/j.bbrc.2009.06.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 06/08/2009] [Indexed: 11/30/2022]
Abstract
We previously described a putative role for inosine monophosphate dehydrogenase (IMPDH), a rate-limiting enzyme in de novo guanine nucleotide biosynthesis, in lipid accumulation. Here we present data which demonstrate that IMPDH activity is required for differentiation of preadipocytes into mature, lipid-laden adipocytes and maintenance of adipose tissue mass. In 3T3-L1 preadipocytes inhibition of IMPDH with mycophenolic acid (MPA) reduced intracellular GTP levels by 60% (p<0.05) and blocked adipogenesis (p<0.05). Co-treatment with guanosine, a substrate in the salvage pathway of nucleotide biosynthesis, restored GTP levels and adipogenesis demonstrating the specificity of these effects. Treatment of diet-induced obese mice with mycophenolate mofetil (MMF), the prodrug of MPA, for 28 days did not affect food intake or lean body mass but reduced body fat content (by 36%, p=0.002) and adipocyte size (p=0.03) and number. These data suggest that inhibition of IMPDH may represent a novel strategy to reduce adipose tissue mass.
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Affiliation(s)
- Hua Su
- Diamantina Institute for Cancer, Immunology and Metabolic Medicine, University of Queensland, Princess Alexandra Hospital, Brisbane, Qld 4102, Australia
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72
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Nair V, Chi G, Shu Q, Julander J, Smee DF. A heterocyclic molecule with significant activity against dengue virus. Bioorg Med Chem Lett 2009; 19:1425-7. [PMID: 19185487 PMCID: PMC2692961 DOI: 10.1016/j.bmcl.2009.01.031] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Revised: 01/06/2009] [Accepted: 01/12/2009] [Indexed: 11/25/2022]
Abstract
There are no specific approved drugs or vaccines for the treatment or prevention of infectious dengue virus and there are very few compounds known that inhibit the replication of this virus. This letter describes the concise synthesis of two uracil-based multifunctional compounds. One of these compounds (1) has strong activity against dengue virus. It also exhibits low activity against a few other RNA viruses, but is highly active against yellow fever virus, a related flavivirus. It is likely that the mechanism of action of the antiviral activity of this compound is through its inhibition of the enzyme, inosine monophosphate dehydrogenase (IMPDH). Molecular modeling studies reveal that the compound can have specific hydrogen bonding interactions with a number of amino acids in the active site of IMPDH, a stacking interaction with the bound natural substrate, IMP, and the ability to interfere with the binding of NAD(+) with IMPDH, prior to the hydration step.
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Affiliation(s)
- Vasu Nair
- Department of Pharmaceutical and Biomedical Sciences and the Center for Drug Discovery, University of Georgia, Athens, GA 30602, USA
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73
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Reduced ribavirin antiviral efficacy via nucleoside transporter-mediated drug resistance. J Virol 2009; 83:4538-47. [PMID: 19244331 DOI: 10.1128/jvi.02280-08] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Treatment for hepatitis C virus infection currently consists of pegylated interferon and ribavirin (RBV), a nucleoside analog. Although RBV clearly plays a role in aiding the treatment response, its antiviral mechanism is unclear. Regardless of the specific mechanism of RBV, we hypothesize that differences in levels of cellular uptake of RBV may affect antiviral efficacy and treatment success and that cells may become RBV resistant through reduced uptake. We monitored RBV uptake in various cell lines and determined the effect of uptake capacity on viral replication. RBV-resistant cells demonstrated reduced RBV uptake and increased growth of a model RNA virus, poliovirus, in the presence of RBV. Overexpression of equilibrative nucleoside transporter 1 (ENT1) or concentrative nucleoside transporter 3 (CNT3) increased RBV uptake in RBV-sensitive cell lines and restored the uptake defect in most RBV-resistant cell lines. However, CNT3 is not expressed in Huh-7 liver cells, and inhibition of concentrative transport did not affect RBV uptake. Blocking equilibrative transport using the inhibitor nitrobenzylmercaptopurine riboside recapitulated the RBV-resistant phenotype in RBV-sensitive cell lines, with a reduction in RBV uptake and increased poliovirus growth. Taken together, these results indicate that RBV uptake is restricted primarily to ENT1 in the cell lines examined. Interestingly, some RBV-resistant cell lines may compensate for reduced ENT1-mediated nucleoside uptake by increasing the activity of an alternative nucleoside transporter, ENT2. It is possible that RBV uptake affects the antiviral treatment response, either through natural differences in patients or through acquired resistance.
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74
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Chen L, Wilson DJ, Labello NP, Jayaram HN, Pankiewicz KW. Mycophenolic acid analogs with a modified metabolic profile. Bioorg Med Chem 2008; 16:9340-5. [DOI: 10.1016/j.bmc.2008.08.062] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Revised: 08/20/2008] [Accepted: 08/26/2008] [Indexed: 11/26/2022]
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75
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Chen L, Petrelli R, Olesiak M, Wilson DJ, Labello NP, Pankiewicz KW. Bis(sulfonamide) isosters of mycophenolic adenine dinucleotide analogues: inhibition of inosine monophosphate dehydrogenase. Bioorg Med Chem 2008; 16:7462-9. [PMID: 18583139 DOI: 10.1016/j.bmc.2008.06.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 06/03/2008] [Accepted: 06/05/2008] [Indexed: 11/25/2022]
Abstract
Synthesis of novel inhibitors of human IMP dehydrogenase is described. These inhibitors are isosteric methylenebis(sulfonamide) analogues 5-8 of earlier reported mycophenolic adenine methylenebis(phosphonate)s 1-3. The parent bis(phosphonate) 1 and its bis(sulfonamide) analogue 5 showed similar sub-micromolar inhibitory activity against IMPDH2 (K(i) approximately 0.2 microM). However, the bis(sulfonamide) analogues 6 and 8 substituted at the position 2 of adenine were approximately 3- to 10-fold less potent inhibitors of IMPDH2 (K(i)=0.3-0.4 microM) than the corresponding parent bis(phosphonate)s 2 and 3 (K(i)=0.04-0.11 microM), respectively.
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Affiliation(s)
- Liqiang Chen
- Center for Drug Design, Academic Health Center, University of Minnesota, 516 Delaware Street S.E., Minneapolis, MN 55455, USA
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76
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Shu Q, Nair V. Inosine monophosphate dehydrogenase (IMPDH) as a target in drug discovery. Med Res Rev 2008; 28:219-32. [PMID: 17480004 DOI: 10.1002/med.20104] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Inosine monophosphate dehydrogenase (IMPDH) is a key enzyme of de novo purine nucleotide biosynthesis and is viewed as an important target in the quest for discovery of drugs in the antiviral, antibacterial and anticancer therapeutic areas. This review focuses on the medicinal chemistry, drug discovery and chemical biology of IMPDH. Examples of IMP and cofactor site-directed inhibitors, allosteric inhibitors and isoform-selective inhibitors are presented. Comparison of IMPDHs from different organisms is also made to facilitate the design of species-selective IMPDH inhibitors for drug discovery. Special emphasis in the review is placed on IMPDH from Mycobacterium tuberculosis.
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Affiliation(s)
- Qingning Shu
- The Center for Drug Discovery and the Department of Pharmaceutical and Biomedical Sciences, R. C. Wilson PH, University of Georgia, Athens, Georgia 30602, USA
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77
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Polyak SJ. Resistance of HBV and HCV to antiviral therapies. Future Virol 2008. [DOI: 10.2217/17460794.3.3.221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Stephen J Polyak
- University of Washington, Department of Laboratory Medicine, Virology 359690, 325 9th Avenue, Seattle, WA 98104, USA
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78
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Nair V, Shu Q. Inosine monophosphate dehydrogenase as a probe in antiviral drug discovery. Antivir Chem Chemother 2008; 18:245-58. [PMID: 18046958 DOI: 10.1177/095632020701800501] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Inosine monophosphate (IMP) dehydrogenase (IMPDH) is a significant enzyme in the purine nucleotide biosynthetic pathway. IMPDH is viewed as an important biological target in the quest for drugs in the antiviral therapeutic area. This review article is focused on the chemistry and biology of IMPDH inhibitors and the use of IMPDH inhibition data as a probe in antiviral drug discovery. Examples of both inosine 5' monophosphate and NAD+ site-directed inhibitors are presented. Correlation of antiviral activities with IMPDH inhibition is discussed.
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Affiliation(s)
- Vasu Nair
- The Center for Drug Discovery, Department of Pharmaceutical and Biomedical Sciences, The University of Georgia, Athens, GA, USA.
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79
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Chen L, Wilson D, Jayaram HN, Pankiewicz KW. Dual inhibitors of inosine monophosphate dehydrogenase and histone deacetylases for cancer treatment. J Med Chem 2007; 50:6685-91. [PMID: 18038969 DOI: 10.1021/jm070864w] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mycophenolic acid (MPA), an inhibitor of IMP-dehydrogenase (IMPDH), is used worldwide in transplantation. Recently, numerous studies showed its importance in cancer treatment. Consequently, MPA entered clinical trials in advanced multiple myeloma patients. Suberoylanilide hydroxamic acid (SAHA), a potent differentiation agent acting through inhibition of histone deacetylases (HDACs), was recently approved for treatment of cutaneous T cell lymphoma. We report herein the synthesis of dual inhibitors of IMPDH and HDACs. We found that mycophenolic hydroxamic acid (9, MAHA) inhibits both IMPDH (Ki=30 nM) and HDAC (IC50=5.0 microM). A modification of SAHA with groups known to interact with IMPDH afforded a SAHA analogue 14, which inhibits IMPDH (Ki=1.7 microM) and HDAC (IC50=0.06 microM). Both MAHA (IC50=4.8 microM) and SAHA analogue 14 (IC50=7.7 microM) were more potent than parent compounds as antiproliferation agents. They were also significantly more potent as differentiation inducers.
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Affiliation(s)
- Liqiang Chen
- Center for Drug Design, University of Minnesota, Minneapolis 55455, USA
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80
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Watterson SH, Chen P, Zhao Y, Gu HH, Dhar TGM, Xiao Z, Ballentine SK, Shen Z, Fleener CA, Rouleau KA, Obermeier M, Yang Z, McIntyre KW, Shuster DJ, Witmer M, Dambach D, Chao S, Mathur A, Chen BC, Barrish JC, Robl JA, Townsend R, Iwanowicz EJ. Acridone-based inhibitors of inosine 5'-monophosphate dehydrogenase: discovery and SAR leading to the identification of N-(2-(6-(4-ethylpiperazin-1-yl)pyridin-3-yl)propan-2-yl)-2- fluoro-9-oxo-9,10-dihydroacridine-3-carboxamide (BMS-566419). J Med Chem 2007; 50:3730-42. [PMID: 17585753 DOI: 10.1021/jm070299x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Inosine monophosphate dehydrogenase (IMPDH), a key enzyme in the de novo synthesis of guanosine nucleotides, catalyzes the irreversible nicotinamide-adenine dinucleotide dependent oxidation of inosine-5'-monophosphate to xanthosine-5'-monophosphate. Mycophenolate Mofetil (MMF), a prodrug of mycophenolic acid, has clinical utility for the treatment of transplant rejection based on its inhibition of IMPDH. The overall clinical benefit of MMF is limited by what is generally believed to be compound-based, dose-limiting gastrointestinal (GI) toxicity that is related to its specific pharmacokinetic characteristics. Thus, development of an IMPDH inhibitor with a novel structure and a different pharmacokinetic profile may reduce the likelihood of GI toxicity and allow for increased efficacy. This article will detail the discovery and SAR leading to a novel and potent acridone-based IMPDH inhibitor 4m and its efficacy and GI tolerability when administered orally in a rat adjuvant arthritis model.
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Affiliation(s)
- Scott H Watterson
- Bristol-Myers Squibb Pharmaceutical Research Institute, Post Office Box 4000, Princeton, New Jersey 08543, USA.
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81
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Cornberg M, Deterding K, Manns MP. Present and future therapy for hepatitis C virus. Expert Rev Anti Infect Ther 2007; 4:781-93. [PMID: 17140355 DOI: 10.1586/14787210.4.5.781] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The treatment of hepatitis C virus (HCV) infection has developed enormously over recent years. Early treatment of acute HCV infection with interferon-alpha can prevent chronicity and a significant proportion of patients with chronic HCV can be cured with the current standard therapy consisting of pegylated interferon-alpha and ribavirin. However, the improvement of current treatment regimens and the development of new antiviral drugs will be essential within the next few years. This review focuses on the present and future concepts for treating HCV infection, including prevention of infection, antiviral therapy of acute and chronic HCV and the management of patients after liver transplantation.
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Affiliation(s)
- Markus Cornberg
- German Competence Network for Viral Hepatitis (Kompetenznetz Hepatitis), Medizinische Hochschule Hannover, Department of Gastroenterology, Hepatology, and Endocrinology, Carl-Neuberg Str. 1, D-30625 Hannover, Germany.
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82
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Abstract
Therapy of hepatitis C virus (HCV) infection may prevent progression to cirrhosis, hepatocellular carcinoma and end-stage liver disease. The cornerstone of treatment has long been standard IFN-alpha, the use of which was associated with a sustained biochemical and viral response in only a small proportion of patients. More recently, the success of interferon-based regimens has substantially improved due to the combination with the guanosine analogue ribavirin and to the advent of pegylated interferon formulations. However, even the most up-to-date regimens fail to cure the infection in many cases and are limited by side effects and high costs. A better understanding of the HCV genomic organisation, the elucidation of the three-dimensional structures of virally encoded enzymes and the recent development of a HCV-replicon system in human hepatoma (Huh-7) cells have led to significant advances in the development of new antiviral compounds, many of which are under evaluation in clinical trials. The aim of this review is to trace a brief overview of the progress made by interferon-based treatments for hepatitis C since their introduction in the early 1990s, and to highlight the results of recent clinical studies concerning new and emerging drugs.
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Affiliation(s)
- Pierluigi Toniutto
- Internal Medicine, Medical Liver Transplantation Unit, DPMSC, University of Udine, Clinica Medica, Policlinico Universitario, Piazzale SM della Misericordia 1, 33100 Udine, Italy.
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83
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Stein RA. Antiviral Drug Discovery for Emerging Diseases and Bioterrorism Threats. Edited by Paul F. Torrence, John Wiley and Sons Inc., Hoboken, NJ, 2005, x + 420 pp. ISBN 0-471-66827-3. Ann Biomed Eng 2006. [DOI: 10.1007/s10439-006-9166-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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84
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Daurel-Receveur M, Titier K, Picard SP, Ducint D, Moore N, Molimard M. Fully Automated Analytical Method for Mycophenolic Acid Quantification in Human Plasma Using On-line Solid Phase Extraction and High Performance Liquid Chromatography With Diode Array Detection. Ther Drug Monit 2006; 28:505-11. [PMID: 16885717 DOI: 10.1097/00007691-200608000-00004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We have developed a new fully automated method for mycophenolic (MPA) acid quantification in plasma to optimize therapeutic drug monitoring of tranplant patients. This method involved solid-phase extraction on disposable extraction cartridges and reversed-phase high-performance liquid chromatography with diode array detection. Solid-phase extraction was performed automatically by an automated sample with extraction catridges system. After washing, MPA was eluted from the cartridge onto a Chromolith RP-18e column. MPA and the internal standard were detected at 306 nm. The retention time of MPA was 6.3 minutes. The developed method was linear from 0.2 to 20 microg/mL. The limit of quantification was 0.2 microg/mL. The method showed a good precision with intraday and interday variation coefficient less than 6%. The intraday accuracy ranged from 97.6% to 100.4% and the interday accuracy varied from 97.1% to 100.8%. The extraction efficiency was greater than 90%. This method is simple and shows a good specificity with respect to commonly co-prescripted drugs.
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Affiliation(s)
- Mathilde Daurel-Receveur
- CHU de Bordeaux, Département de Pharmacologie Clinique et de Toxicologie, Bordeaux F33000, France
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85
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Miles KK, Kessler FK, Webb LJ, Smith PC, Ritter JK. Adenovirus-Mediated Gene Therapy to Restore Expression and Functionality of Multiple UDP-Glucuronosyltransferase 1A Enzymes in Gunn Rat Liver. J Pharmacol Exp Ther 2006; 318:1240-7. [PMID: 16763095 DOI: 10.1124/jpet.106.104810] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The Gunn rat has been a valuable model for investigating the effect of UDP-glucuronosyltransferase 1A (UGT1A) deficiencies on drug metabolism and toxicity, but it is limited in some aspects. For example, the native Gunn rat model cannot distinguish between hepatic and extrahepatic UGT1A deficiencies in toxicological mechanisms. To extend the model's utility, we investigated the use of replication-defective recombinant UGT1A adenoviruses for the purpose of selectively restoring hepatic UGT1A function. Mycophenolic acid, the active metabolite of the anti-transplant rejection drug mycophenolate mofetil and suspected gastrointestinal toxicant, was used as a model UGT1A-dependent substrate. Treatment with UGT1A adenoviruses normalized the plasma mycophenolic acid and 7-O-mycophenolate glucuronide (MPAG) (concentration-time curves after mycophenolic acid administration (80 mg/kg intraperitoneally). Functional reconstitution was also apparent in the correction of the mycophenolic acid t(1/2alpha) and the area under the curve (AUC)(MPA,0-8 h)/AUC(MPAG,0-8 h) ratio. Twenty-four hours after administration of mycophenolic acid, severe signs of toxicity were noted in the naive Gunn group, including reduced food consumption. The effect on food consumption was reduced but not completely prevented in the UGT adenovirus-treated Gunn rats. In vitro analyses indicated adenovirus dose-dependent reconstitution of mycophenolic acid UGT activities and UGT1A contents in liver but not intestinal microsomes. In the highest adenovirus dose group, the liver microsomal UGT1A markers exceeded those of the heterozygote controls. The ability to selectively manipulate multiple hepatic UGT1A enzymes in Gunn rats should provide a novel way to assess the importance of intestinal or other extrahepatic UGT1A enzymes in toxicities induced by mycophenolic acid and other cytotoxic drugs and dietary agents.
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Affiliation(s)
- Kristini K Miles
- Department of Pharmacology and Toxicology, Virginia Commonwealth University Medical Center, Richmond, VA 23298, USA
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86
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Dzidic A, Prgomet C, Mohr A, Meyer K, Bauer J, Meyer HHD, Pfaffl MW. Effects of Mycophenolic Acid on Inosine Monophosphate Dehydrogenase I and II mRNA Expression in White Blood Cells and Various Tissues in Sheep. ACTA ACUST UNITED AC 2006; 53:163-9. [PMID: 16629948 DOI: 10.1111/j.1439-0442.2006.00809.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Mycophenolic acid (MPA) is a mycotoxin commonly found as Penicillium genus secondary metabolite in feedstuffs and silages. Feeding with MPA contaminated silages may modulate the immune system in the farm animals and can cause appetite lost, ketosis, paralysis and abortion. The aim of the present study was to characterize the long-term MPA effect on both the inosine monophosphate dehydrogenase (IMPDH) isoforms I and II mRNA expression in white blood cells (WBC) and various tissue of healthy sheep. In treated animals 300 mg MPA/day/sheep was applied. In all investigated tissues the IMPDH I and II mRNA was abundant: WBC, spleen, thymus, ileum, jejunum, kidney, liver, pharyngeal and mesenterial lymph node. An efficiency-corrected relative quantification of the IMPDH types I and II isoforms mRNA were performed by normalizing with the constant reference gene expression of beta-actin. High IMPDH I mRNA expression levels were seen in kidney > mesenterial lymph node > jejunum > spleen > pharyngeal lymph node. Medium and low abundance was found in ileum > WBC > liver > thymus. Type II mRNA was highly expressed in liver > thymus > jejunum. In pharyngeal lymph node > spleen > ileum > mesenterial lymph node > kidney > WBC medium to low IMPDH II mRNA concentrations were detected. Under MPA treatment the IMPDH I mRNA expression was not significantly regulated in WBC, only trends of down- and upregulation were observed. Surprisingly in jejunum an upregulation could be observed (P < 0.05). In pharyngeal lymph node a tendency to downregulation was shown. This may be due to frequent ruminant activities and frequent exposition of MPA to the pharyngeal lymph nodes. In contrast to type I mRNA expression, IMPDH II mRNA was significantly downregulated in ileum (3.4-fold, P < 0.01) and tendencies in downregulation could be seen in jejunum (5.1-fold, P = 0.14). In addition, significant downregulation of IMPDH II gene expression over the entire feeding experiment could be shown in WBC of MPA-treated animals compared with untreated animals (P < 0.05). In conclusion, the recent study demonstrates that feeding sheep with MPA-contaminated silage did not induce IMPDH I mRNA expression in various tissues and blood, except in jejunum, but has suppressive effects on IMPDH II mRNA expression in WBC and ileum.
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Affiliation(s)
- A Dzidic
- Physiology, Center of Life and Food Science, Technical University of Munich, Freising-Weihenstephan, Germany
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87
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Hodo Y, Tsuji K, Mizukoshi E, Yamashita T, Sakai A, Nakamoto Y, Honda M, Kaneko S. Pure red cell aplasia associated with concomitant use of mycophenolate mofetil and ribavirin in post-transplant recurrent hepatitis C. Transpl Int 2006; 19:170-1. [PMID: 16441367 DOI: 10.1111/j.1432-2277.2005.00242.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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88
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Abstract
The nucleoside analogue ribavirin has antiviral activity against many distinct viruses both in vitro and in vivo. Five distinct mechanisms have been proposed to explain the antiviral properties of ribavirin. These include both indirect mechanisms (inosine monophosphate dehydrogenase inhibition, immunomodulatory effects) and direct mechanisms (interference with RNA capping, polymerase inhibition, lethal mutagenesis). Recent concerns about bioterrorism have renewed interest in exploring the antiviral activity of ribavirin against unique viruses. In this paper, we review the proposed mechanisms of action with emphasis on recent discoveries, as well as the implications of ribavirin resistance. Evidence exists to support each of the five proposed mechanisms of action, and distinct virus/host combinations may preferentially favour one or more of these mechanisms during antiviral therapy. Copyright © 2005 John Wiley & Sons, Ltd.
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Affiliation(s)
- Jason D. Graci
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Craig E. Cameron
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
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89
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Fujita N, Kaito M, Tanaka H, Horiike S, Urawa N, Sugimoto R, Konishi M, Watanabe S, Adachi Y. Hepatitis C virus free-virion and immune-complex dynamics during interferon therapy with and without ribavirin in genotype-1b chronic hepatitis C patients. J Viral Hepat 2006; 13:190-8. [PMID: 16475995 DOI: 10.1111/j.1365-2893.2005.00665.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The Synergistic effect of interferon (IFN) and ribavirin for patients with chronic hepatitis C has been demonstrated, but ribavirin has no apparent direct antiviral effect against hepatitis C virus (HCV) when used as monotherapy. To elucidate the mechanism of ribavirin on enhanced HCV eradication when used in combination therapy, we investigated the serum HCV dynamics of free-virions (FV) and immune-complexes (IC) in genotype-1b infected patients treated with IFN-alpha2b alone (n = 11) or in combination with ribavirin (n = 15). Serum FV- and IC-HCV RNA were separated by immunoprecipitation using anti-human immunoglobulin and quantified serially using real-time detection polymerase chain reaction. At the first phase (day 0-2), the decline of FV- and IC-HCV RNA was similar between the two treatment groups. At the second phase (day 2-28), the decline of IC was significantly faster in patients treated with IFN plus ribavirin compared with IFN alone [exponential decay slope = 0.079 +/- 0.036 vs 0.048 +/- 0.027 log10/day, P = 0.0248; half-life = 81.1 +/- 21.4 vs 135.1 +/- 61.4 h, P = 0.0053], although the second phase FV-decline was not significantly different between the two treatment groups. The fast second phase decline of IC was associated with sustained virological response to therapy. These results suggest that ribavirin may modulate the humoral immune response against HCV and trigger a favourable response to IFN. In conclusion, analysis of early IC-HCV dynamics is useful for predicting the response to therapy and for understanding the mechanism of action of antiviral drugs in chronic hepatitis C patients.
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Affiliation(s)
- N Fujita
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Mie University School of Medicine, Mie, Japan.
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90
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Beevers RE, Buckley GM, Davies N, Fraser JL, Galvin FC, Hannah DR, Haughan AF, Jenkins K, Mack SR, Pitt WR, Ratcliffe AJ, Richard MD, Sabin V, Sharpe A, Williams SC. Low molecular weight indole fragments as IMPDH inhibitors. Bioorg Med Chem Lett 2006; 16:2535-8. [PMID: 16483769 DOI: 10.1016/j.bmcl.2006.01.089] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Revised: 01/19/2006] [Accepted: 01/19/2006] [Indexed: 11/15/2022]
Abstract
The study of non-oxazole containing indole fragments as inhibitors of inosine monophosphate dehydrogenase (IMPDH) is described. The synthesis and in vitro inhibitory values for IMPDH II are discussed.
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91
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Lee CM, Kee KM, Hung CH, Eng HL, Chang CH, Huang CM, Wang JH, Hu TH, Lu SN, Changchien CS, Chen WJ. Hepatic Interferon Receptor Mrna Expression: Clinical Relevance and Its Relationship with Effectiveness of Interferon plus Ribavirin Therapy in Patients with Genotype 1B Hepatitis C Virus Infection. Antivir Ther 2006. [DOI: 10.1177/135965350601100107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background/aims Hepatic expression of interferon (IFN) receptor mRNA has been shown to correlate with the effectiveness of IFN monotherapy in patients with chronic hepatitis C virus (HCV) infection. We investigated the expression of hepatic IFN receptor alpha/beta (IFNAR2c) mRNA and its association with the effectiveness of IFN plus ribavirin (RBV) therapy and with the clinical features in patients with HCV genotype 1b (HCV-1b) infection. Methods A total of 42 naive patients who had chronic HCV-1b infection were treated with IFN alpha-2b 3 MU or 5 MU three times weekly plus RBV for 24 weeks. Hepatic IFNAR2c mRNA was quantified by real-time RT-PCR. Results There was no significant difference in the mean expression level of IFNAR2c mRNA between patients with sustained virological response (SVR) and non-SVR (0.069 ±0.042 versus 0.053 ±0.033, P=0.182). Multiple linear regression analysis showed that lower fibrosis scores ( P=0.006) and younger age ( P=0.03) were associated with hepatic IFNAR2c mRNA expression with r2=0.34. Conclusions Hepatic IFNAR2c mRNA expression may not be useful for predicting the response to IFN plus RBV therapy in patients with HCV-1b infection, but appeared to correlate inversely with the fibrosis stage and age.
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Affiliation(s)
- Chuan-Mo Lee
- Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Kwong-Ming Kee
- Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Chao-Hung Hung
- Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Hock-Liew Eng
- Department of Pathology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Chien-Hwa Chang
- Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Chao-Min Huang
- Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Jing-Houng Wang
- Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Tsung-Hui Hu
- Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Sheng-Nan Lu
- Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Chi-Sin Changchien
- Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Wei-Jen Chen
- Department of Pathology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
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Abstract
A variety of therapeutic options are available to treat psoriasis and atopic dermatitis (AD). Local agents typically are used to treat localized and milder forms of disease, whereas phototherapy and systemic agents are used for more generalized and severe disease. Various combinations and sequences of topical or systemic therapies, or both, have been utilized in the treatment of psoriasis and, less frequently, of AD. Conventional systemic therapies for psoriasis, such as corticosteroids, oral calcineurin inhibitors, antimetabolites, and retinoids, are limited by their propensity to cause serious side effects. More recently, a number of immunobiologic agents, such as monoclonal antibodies, recombinant cytokines, and fusion proteins, have been approved by the Food and Drug Administration or are undergoing development as systemic antipsoriatic treatments. In many of these categories, a number of exciting new therapies are in development that may augment the existing armamentarium available to clinicians for the treatment of inflammatory skin diseases.
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Affiliation(s)
- Alice B Gottlieb
- Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ 08901, USA.
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93
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Birch HL, Buckley GM, Davies N, Dyke HJ, Frost EJ, Gilbert PJ, Hannah DR, Haughan AF, Madigan MJ, Morgan T, Pitt WR, Ratcliffe AJ, Ray NC, Richard MD, Sharpe A, Taylor AJ, Whitworth JM, Williams SC. Novel 7-methoxy-6-oxazol-5-yl-2,3-dihydro-1H-quinazolin-4-ones as IMPDH inhibitors. Bioorg Med Chem Lett 2005; 15:5335-9. [PMID: 16202581 DOI: 10.1016/j.bmcl.2005.06.108] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2004] [Revised: 06/02/2005] [Accepted: 06/23/2005] [Indexed: 11/19/2022]
Abstract
The synthesis and biological activity of a novel series of 7-methoxy-6-oxazol-5-yl-2,3-dihydro-1H-quinazolin-4-ones are described. Some of these compounds were found to be potent inhibitors of inosine 5'-monophosphate dehydrogenase type II (IMPDH II).
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Affiliation(s)
- Helen L Birch
- UCB Celltech, Granta Park, Great Abington, Cambridge, CB1 6GS, UK
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95
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Miles KK, Stern ST, Smith PC, Kessler FK, Ali S, Ritter JK. AN INVESTIGATION OF HUMAN AND RAT LIVER MICROSOMAL MYCOPHENOLIC ACID GLUCURONIDATION: EVIDENCE FOR A PRINCIPAL ROLE OF UGT1A ENZYMES AND SPECIES DIFFERENCES IN UGT1A SPECIFICITY. Drug Metab Dispos 2005; 33:1513-20. [PMID: 16033946 DOI: 10.1124/dmd.105.004663] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mycophenolic acid (MPA; 1,3-dihydro-4-hydroxy-6-methoxy-7-methyl-3-oxo-5-isobenzylfuranyl)-4-methyl-4-hexenoate), the active metabolite of the immunosuppressant prodrug, mycophenolate mofetil, undergoes glucuronidation to its 7-O-glucuronide as a primary route of metabolism. Because differences in glucuronidation may influence the efficacy and/or toxicity of MPA, we investigated the MPA UDP-glucuronosyltransferase (UGT) activities of human liver microsomes (HLMs) and rat liver microsomes with the goal of identifying UGTs responsible for MPA catalysis. HLMs (n = 23) exhibited higher average MPA glucuronidation rates (14.7 versus 6.0 nmol/mg/min, respectively, p < 0.001) and higher apparent affinity for MPA (K(m) = 0.082 mM versus 0.20 mM, p < 0.001) compared with rat liver microsomes. MPA UGT activities were reduced >80% in liver microsomes from Gunn rats. To identify the active enzymes, human and rat UGT1A enzymes were screened for MPA-glucuronidating activity. UGT1A9 was the only human liver-expressed UGT1A enzyme with significant activity and exhibited both high affinity (K(m) = 0.077 mM) and high activity (V(max) = 28 nmol x min(-1) x mg(-1)). Spearman correlation analyses revealed a stronger relationship between HLM MPA UGT activities and 1A9-like content (r(2) = 0.79) relative to 1A1 (r(2) = 0.20), 1A4-like (r(2) = 0.22), and 1A6 (r(2) = 0.41) protein. A different profile was observed for rat with three active liver-expressed UGT1A enzymes: 1A1 (medium affinity/capacity), 1A6 (low affinity/medium capacity), and 1A7 (high affinity/capacity). Our data suggest that UGT1A enzymes are the major contributors to hepatic MPA metabolism in both species, but 1A9 is dominant in human, whereas 1A1 and 1A7 are likely the principal mediators in control rat liver. This information should be useful for interpretation of MPA pharmacokinetic and toxicity data in clinical and animal studies.
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Affiliation(s)
- Kristini K Miles
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Medical College of Virginia Campus, 1217 E. Marshall Street, Richmond, VA 23298-0613, USA
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96
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Buckley GM, Davies N, Dyke HJ, Gilbert PJ, Hannah DR, Haughan AF, Hunt CA, Pitt WR, Profit RH, Ray NC, Richard MD, Sharpe A, Taylor AJ, Whitworth JM, Williams SC. Quinazolinethiones and quinazolinediones, novel inhibitors of inosine monophosphate dehydrogenase: synthesis and initial structure-activity relationships. Bioorg Med Chem Lett 2005; 15:751-4. [PMID: 15664851 DOI: 10.1016/j.bmcl.2004.11.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Revised: 11/02/2004] [Accepted: 11/04/2004] [Indexed: 11/23/2022]
Abstract
The development of a series of novel quinazolinethiones and quinazolinediones as inhibitors of inosine monophosphate dehydrogenase (IMPDH) is described. The synthesis, in vitro inhibitory values for IMPDH II and in vitro inhibitory value for PBMC proliferation are discussed.
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Affiliation(s)
- George M Buckley
- Celltech R and D, Granta Park, Great Abington, Cambridge CB1 6GS, UK
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97
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Whitehead JP, Simpson F, Hill MM, Thomas EC, Connolly LM, Collart F, Simpson RJ, James DE. Insulin and oleate promote translocation of inosine-5' monophosphate dehydrogenase to lipid bodies. Traffic 2005; 5:739-49. [PMID: 15355510 DOI: 10.1111/j.1600-0854.2004.00217.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In the present study we identify inosine-5' monophosphate dehydrogenase (IMPDH), a key enzyme in de novo guanine nucleotide biosynthesis, as a novel lipid body-associated protein. To identify new targets of insulin we performed a comprehensive 2-DE analysis of (32)P-labelled proteins isolated from 3T3-L1 adipocytes (Hill et al. J Biol Chem 2000; 275: 24313-24320). IMPDH was identified by liquid chromatography/tandem mass spectrometry as a protein which was phosphorylated in a phosphatidylinositol (PI) 3-kinase-dependent manner upon insulin treatment. Although insulin had no significant effect on IMPDH activity, we observed translocation of IMPDH to lipid bodies following insulin treatment. Induction of lipid body formation with oleic acid promoted dramatic redistribution of IMPDH to lipid bodies, which appeared to be in contact with the endoplasmic reticulum, the site of lipid body synthesis and recycling. Inhibition of PI 3-kinase blocked insulin- and oleate-induced translocation of IMPDH and reduced oleate-induced lipid accumulation. However, we found no evidence of oleate-induced IMPDH phosphorylation, suggesting phosphorylation and translocation may not be coupled events. These data support a role for IMPDH in the dynamic regulation of lipid bodies and fatty acid metabolism and regulation of its activity by subcellular redistribution in response to extracellular factors that modify lipid metabolism.
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Affiliation(s)
- Jonathan P Whitehead
- Department of Diabetes & Obesity, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia.
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El-Araby ME, Bernacki RJ, Makara GM, Pera PJ, Anderson WK. Synthesis, molecular modeling, and evaluation of nonphenolic indole analogs of mycophenolic acid. Bioorg Med Chem 2005; 12:2867-79. [PMID: 15142547 DOI: 10.1016/j.bmc.2004.03.048] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2003] [Revised: 03/09/2004] [Accepted: 03/19/2004] [Indexed: 11/24/2022]
Abstract
Based on the promising activity of an indole-3-carboxamide derivative, a nonphenolic analog of mycophenolic acid (MPA), we report herein the synthesis of a compound containing two important features for the activity of MPA, the ring methoxy and methyl. The synthesis was accomplished using two strategies; a method dependent on stepwise building of the hexenoate side chain followed by the indolecarboxamide ring system, and a convergent route that depended on 1,3-sigmatropic rearrangement as a key step. Docking experiments on both Chinese Hamster and Human Type-II inosine monophosphate dehydrogenase (IMPDH) showed that this compound has potential binding interactions with the NAD site. The analogs showed no activity against MCF7-S, MCF7-R, or IGR-OV1 cancer cells.
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Affiliation(s)
- Moustafa E El-Araby
- School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York, 14260 USA.
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100
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