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Zhu W, Xu M, Chen CZ, Guo H, Shen M, Hu X, Shinn P, Klumpp-Thomas C, Michael SG, Zheng W. Identification of SARS-CoV-2 3CL Protease Inhibitors by a Quantitative High-Throughput Screening. ACS Pharmacol Transl Sci 2020; 3:1008-1016. [PMID: 33062953 PMCID: PMC7507806 DOI: 10.1021/acsptsci.0c00108] [Citation(s) in RCA: 140] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Indexed: 12/13/2022]
Abstract
The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emphasized the urgency to develop effective therapeutics. Drug repurposing screening is regarded as one of the most practical and rapid approaches for the discovery of such therapeutics. The 3C-like protease (3CLpro), or main protease (Mpro) of SARS-CoV-2 is a valid drug target as it is a specific viral enzyme and plays an essential role in viral replication. We performed a quantitative high-throughput screening (qHTS) of 10 755 compounds consisting of approved and investigational drugs, and bioactive compounds using a SARS-CoV-2 3CLpro assay. Twenty-three small molecule inhibitors of SARS-CoV-2 3CLpro have been identified with IC50s ranging from 0.26 to 28.85 μM. Walrycin B (IC50 = 0.26 μM), hydroxocobalamin (IC50 = 3.29 μM), suramin sodium (IC50 = 6.5 μM), Z-DEVD-FMK (IC50 = 6.81 μM), LLL-12 (IC50 = 9.84 μM), and Z-FA-FMK (IC50 = 11.39 μM) are the most potent 3CLpro inhibitors. The activity of the anti-SARS-CoV-2 viral infection was confirmed in 7 of 23 compounds using a SARS-CoV-2 cytopathic effect assay. The results demonstrated a set of SARS-CoV-2 3CLpro inhibitors that may have potential for further clinical evaluation as part of drug combination therapies to treating COVID-19 patients and as starting points for chemistry optimization for new drug development.
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Affiliation(s)
- Wei Zhu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
| | - Miao Xu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
| | - Catherine Z Chen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
| | - Hui Guo
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
| | - Min Shen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
| | - Xin Hu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
| | - Paul Shinn
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
| | - Carleen Klumpp-Thomas
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
| | - Samuel G Michael
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
| | - Wei Zheng
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850, United States
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Zhu W, Xu M, Chen CZ, Guo H, Shen M, Hu X, Shinn P, Klumpp-Thomas C, Michael SG, Zheng W. Identification of SARS-CoV-2 3CL Protease Inhibitors by a Quantitative High-throughput Screening. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.07.17.207019. [PMID: 32803196 PMCID: PMC7427131 DOI: 10.1101/2020.07.17.207019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emphasized the urgency to develop effective therapeutics. Drug repurposing screening is regarded as one of the most practical and rapid approaches for the discovery of such therapeutics. The 3C like protease (3CL pro ), or main protease (M pro ) of SARS-CoV-2 is a valid drug target as it is a specific viral enzyme and plays an essential role in viral replication. We performed a quantitative high throughput screening (qHTS) of 10,755 compounds consisting of approved and investigational drugs, and bioactive compounds using a SARS-CoV-2 3CL pro assay. Twenty-three small molecule inhibitors of SARS-CoV-2 3CL pro have been identified with IC50s ranging from 0.26 to 28.85 μM. Walrycin B (IC 50 = 0.26 µM), Hydroxocobalamin (IC 50 = 3.29 µM), Suramin sodium (IC 50 = 6.5 µM), Z-DEVD-FMK (IC 50 = 6.81 µM), LLL-12 (IC 50 = 9.84 µM), and Z-FA-FMK (IC 50 = 11.39 µM) are the most potent 3CL pro inhibitors. The activities of anti-SARS-CoV-2 viral infection was confirmed in 7 of 23 compounds using a SARS-CoV-2 cytopathic effect assay. The results demonstrated a set of SARS-CoV-2 3CL pro inhibitors that may have potential for further clinical evaluation as part of drug combination therapies to treating COVID-19 patients, and as starting points for chemistry optimization for new drug development.
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Affiliation(s)
| | | | - Catherine Z. Chen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Hui Guo
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Min Shen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Xin Hu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Paul Shinn
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Carleen Klumpp-Thomas
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Samuel G. Michael
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Wei Zheng
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
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Zhao L, Mwaliko C, Atoni E, Wang Y, Zhang Y, Zhan J, Hu X, Xia H, Yuan Z. Characterization of a Novel Tanay Virus Isolated From Anopheles sinensis Mosquitoes in Yunnan, China. Front Microbiol 2019; 10:1963. [PMID: 31507570 PMCID: PMC6714596 DOI: 10.3389/fmicb.2019.01963] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 08/09/2019] [Indexed: 12/13/2022] Open
Abstract
Globally, mosquitoes are known to be competent vectors to various arboviruses that cause serious and debilitating diseases to humans and animals. Conversely, mosquitoes harbor a wide array of insect specific viruses (ISVs) that are generally neglected. Extensive characterization of these ISVs is important in understanding their persistence infection effect on host behavior and arbovirus transmission. Herein, we report first time isolation of Tanay virus (TANAV) isolate YN15_103_01 in Anopheles sinensis mosquitoes from Yunnan Province, China. Phylogenetically, the isolate’s nucleotide identity had more than 14.47% variance compared to previous TANAV isolates, and it clustered into an independent branch within the genus Sandewavirus in the newly proposed taxon Negevirus. TANAV growth and high titers was attained in Aag2 cells (107 PFU/mL) but with no CPE observed up to 7 days.p.i. compared to C6/36 cells that exhibited extensive CPE at 48 h.p.i. with titers of 107 PFU/mL. Contrarywise, the viral isolate did not replicate in vertebrate cell lines. Electron microscopy analyses showed that its final maturation process takes place in the cell cytoplasm. Notably, the predicted viral proteins were verified to be corresponding to the obtained SDS-PAGE protein bands. Our findings advance forth new and vital knowledge important in understanding insect specific viruses, especially TANAV.
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Affiliation(s)
- Lu Zhao
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Caroline Mwaliko
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Evans Atoni
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yujuan Wang
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yunzhi Zhang
- Yunnan Institute of Endemic Disease Control and Prevention, Dali, China
| | - Jianbo Zhan
- Division for Viral Disease with Detection, Hubei Provincial Center for Disease Control and Prevention, Wuhan, China
| | - Xiaomin Hu
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Han Xia
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Zhiming Yuan
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
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Mechie NC, Goralzcyk AD, Reinhardt L, Mihm S, Amanzada A. Association of serum vitamin B12 levels with stage of liver fibrosis and treatment outcome in patients with chronic hepatitis C virus genotype 1 infection: a retrospective study. BMC Res Notes 2015; 8:260. [PMID: 26109044 PMCID: PMC4479221 DOI: 10.1186/s13104-015-1248-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 06/17/2015] [Indexed: 12/18/2022] Open
Abstract
Background Chronic hepatitis C (CHC) is a global health challenge. New therapeutic agents with excellent sustained virological response (SVR) rates are available mainly in developed countries, while the majority of CHC patients live in countries with low health budget. Predictors of therapeutic response are therefore necessary. Vitamin B12 appears to be involved in hepatitis C virus replication. Methods We therefore studied retrospectively the relationship between baseline serum vitamin B12 levels and clinical features in 116 CHC genotype 1 infected patients. Logistic regression models with univariate and multivariate analysis were used in the statistical analysis. Results Baseline serum vitamin B12 levels were found to be positively associated with serum transaminase activities (AST, p = 0.002, ALT, p = 0.04), baseline viral load (p < 0.0001), stage of fibrosis (p = 0.0001) and favorable interferon-λ3/4 (IFNL3/IFNL4) rs12979860 genotypes (p = 0.04), and inversely with SVR (p < 0.001) as well as with rapid virological response (p = 0.001). Patients with baseline serum vitamin B12 levels below a cut-off value of 570 ng/L achieved a SVR rate of 59% with an odds ratio (OR) of 13.4 [confidence interval (CI) 4.3–41.9, p < 0.0001] compared to patients above the cut-off value. By combining serum vitamin B12 levels and IFNL3/IFNL4 rs12979860 genotypes, patients with baseline serum vitamin B12 levels below the cut-off value of 570 ng/L and IFNL3/IFNL4 rs12979860 CC genotype achieved a SVR rate of even 80% with an OR of 54 (CI 9.9–293, p < 0.0001) compared to patients above the cut-off value and non-CC-genotypes. Conclusion Our data suggest baseline serum vitamin B12 levels as useful noninvasive marker for characterizing CHC patients. They might further help to identify responders to a standard treatment.
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Affiliation(s)
- Nicolae-Catalin Mechie
- Department of Gastroenterology and Endocrinology, University Medical Center Goettingen, Georg-August University Goettingen, Robert Koch Strasse 40, 37075, Göttingen, Germany.
| | - Armin D Goralzcyk
- Division of Internal Medicine, Clinic of Herzberg and Osterode, Dr Froessel Allee, 37412, Herzberg am Harz, Germany.
| | - Lars Reinhardt
- Department of Gastroenterology and Endocrinology, University Medical Center Goettingen, Georg-August University Goettingen, Robert Koch Strasse 40, 37075, Göttingen, Germany.
| | - Sabine Mihm
- Department of Gastroenterology and Endocrinology, University Medical Center Goettingen, Georg-August University Goettingen, Robert Koch Strasse 40, 37075, Göttingen, Germany.
| | - Ahmad Amanzada
- Department of Gastroenterology and Endocrinology, University Medical Center Goettingen, Georg-August University Goettingen, Robert Koch Strasse 40, 37075, Göttingen, Germany.
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Masri OA, Chalhoub JM, Sharara AI. Role of vitamins in gastrointestinal diseases. World J Gastroenterol 2015; 21:5191-5209. [PMID: 25954093 PMCID: PMC4419060 DOI: 10.3748/wjg.v21.i17.5191] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 02/23/2015] [Accepted: 03/31/2015] [Indexed: 02/06/2023] Open
Abstract
A tremendous amount of data from research was published over the past decades concerning the roles of different vitamins in various gastrointestinal diseases. For instance, most vitamins showed an inverse relationship with the risk of colorectal carcinoma as well as other malignancies like gastric and esophageal cancer in observational trials, however interventional trials failed to prove a clear beneficial preventive role. On the other hand, more solid evidence was obtained from high quality studies for a role of certain vitamins in specific entities. Examples for this include the therapeutic role of vitamin E in patients with non-alcoholic steatohepatitis, the additive role of vitamins B12 and D to the standard therapy of chronic hepatitis C virus, the role of vitamin C in reducing the risk of gallstones, the positive outcome with vitamin B12 in patients with aphthous stomatitis, and the beneficial effect of vitamin D and B1 in patients with inflammatory bowel disease. Other potential uses are yet to be elaborated, like those on celiac disease, pancreatic cancer, pancreatitis, cholestasis and other potential fields. Data from several ongoing interventional trials are expected to add to the current knowledge over the coming few years. Given that vitamin supplementation is psychologically accepted by patients as a natural compound with relative safety and low cost, their use should be encouraged in the fields where positive data are available.
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Scalabrino G, Veber D, Tredici G. Relationships between cobalamin, epidermal growth factor, and normal prions in the myelin maintenance of central nervous system. Int J Biochem Cell Biol 2014; 55:232-41. [PMID: 25239885 DOI: 10.1016/j.biocel.2014.09.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/06/2014] [Accepted: 09/08/2014] [Indexed: 01/08/2023]
Abstract
Cobalamin (Cbl), epidermal growth factor (EGF), and prions (PrPs) are key molecules for myelin maintenance in the central and peripheral nervous systems. Cbl and EGF increase normal prion (PrP(C)) synthesis and PrP(C) levels in rat spinal cord (SC) and elsewhere. Cbl deficiency increases PrP(C) levels in rat SC and cerebrospinal fluid (CSF), and decreases PrP(C)-mRNA levels in rat SC. The administration of anti-octapeptide repeat PrP(C) region antibodies (Abs) to Cbl-deficient (Cbl-D) rats prevents SC myelin lesions and a local increase in tumor necrosis factor (TNF)-α levels, whereas anti-TNF-α Abs prevent SC myelin lesions and the increase in SC and CSF PrP(C) levels. As it is known that both Cbl and EGF regulate SC PrP(C) synthesis independently, and that Cbl regulates SC EGF synthesis, EGF may play both Cbl-independent and Cbl-dependent roles. When Cbl-D rats undergo Cbl replacement therapy, SC PrP(C) levels are similar to those observed in Cbl-D rats. In rat frontal cortex (which is marginally affected by Cbl deficiency in histological terms), Cbl deficiency decreases PrP(C) levels and the increase induced by Cbl replacement leads to their normalization. Increased nerve PrP(C) levels are detected in the myelin lesions of the peripheral neuropathy of Cbl-D rats, and CSF PrP(C) levels are also increased in Cbl-D patients (but not in patients with Cbl-unrelated neurological diseases). Various common steps in the downstream signaling pathway of Cbl, EGF, and PrP(C) underlines the close relationship between the three molecules in keeping myelin normal.
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Affiliation(s)
- Giuseppe Scalabrino
- Department of Biomedical Sciences, Laboratory of Neuropathology, University of Milan, 20133 Milano, Italy.
| | - Daniela Veber
- Department of Biomedical Sciences, Laboratory of Neuropathology, University of Milan, 20133 Milano, Italy
| | - Giovanni Tredici
- Department of Translational Medicine and Surgery, University of Milano-Bicocca, 20052 Monza, Italy
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7
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Lee TH, Tillmann HL, Patel K. Individualized therapy for hepatitis C infection: focus on the interleukin-28B polymorphism in directing therapy. Mol Diagn Ther 2014; 18:25-38. [PMID: 24022240 DOI: 10.1007/s40291-013-0053-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Hepatitis C virus—a major global cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma—affects millions of people worldwide. Pegylated interferon (Peg-IFN) and ribavirin (RBV) had been the standard treatment for a decade until availability of the protease inhibitors in 2011. However, current antiviral therapy is still IFN-based and is associated with significant side effects and variable treatment response. Thus, various host and viral factors have been evaluated before and during treatment for the prediction of sustained virologic response to antiviral therapy. In 2009, genome-wide association studies found the single-nucleotide polymorphisms, located near the host interleukin-28B (IL28B) gene that encodes IFN-λ3, to be the best pretreatment predictor of virologic response to Peg-IFN and RBV therapy in chronic hepatitis C genotype 1 patients. Additionally, inosine triphosphatase (ITPA) gene variants were found to be associated with RBV-induced hemolytic anemia, which could affect treatment dose for selected patients. IL28B, ITPA, and other treatment predictors allowed for a potential individualized approach to treat hepatitis C. In the era of increased overall virologic response rates and good tolerability of the rapidly developing non-IFN oral direct-acting antiviral therapy regimens, the need for individualized treatment is likely to diminish. Various predictors of response, including IL28B will likely be of reduced importance in the near future.
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Abstract
The lack of small animal models for hepatitis C virus has impeded the discovery and development of anti-HCV drugs. HCV-IRES plays an important role in HCV gene expression, and is an attractive target for antiviral therapy. In this study, we report a zebrafish model with a biscistron expression construct that can co-transcribe GFP and HCV-core genes by human hepatic lipase promoter and zebrafish liver fatty acid binding protein enhancer. HCV core translation was designed mediated by HCV-IRES sequence and gfp was by a canonical cap-dependent mechanism. Results of fluorescence image and in situ hybridization indicate that expression of HCV core and GFP is liver-specific; RT-PCR and Western blotting show that both core and gfp expression are elevated in a time-dependent manner for both transcription and translation. It means that the HCV-IRES exerted its role in this zebrafish model. Furthermore, the liver-pathological impact associated with HCV-infection was detected by examination of gene markers and some of them were elevated, such as adiponectin receptor, heparanase, TGF-β, PDGF-α, etc. The model was used to evaluate three clinical drugs, ribavirin, IFNα-2b and vitamin B12. The results show that vitamin B12 inhibited core expression in mRNA and protein levels in dose-dependent manner, but failed to impact gfp expression. Also VB12 down-regulated some gene transcriptions involved in fat liver, liver fibrosis and HCV-associated pathological process in the larvae. It reveals that HCV-IRES responds to vitamin B12 sensitively in the zebrafish model. Ribavirin did not disturb core expression, hinting that HCV-IRES is not a target site of ribavirin. IFNα-2b was not active, which maybe resulted from its degradation in vivo for the long time. These findings demonstrate the feasibility of the zebrafish model for screening of anti-HCV drugs targeting to HCV-IRES. The zebrafish system provides a novel evidence of using zebrafish as a HCV model organism.
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9
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Tillmann HL. Vitamins? The magic bullet against hepatitis C. Expert Rev Anti Infect Ther 2012; 10:1273-1277. [DOI: 10.1586/eri.12.127] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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10
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Rosenberg P, Hagen K. Serum B12 levels predict response to treatment with interferon and ribavirin in patients with chronic HCV infection. J Viral Hepat 2011; 18:129-34. [PMID: 20196801 DOI: 10.1111/j.1365-2893.2010.01288.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Vitamin B12 is stored in hepatocytes and inhibits hepatitis C virus (HCV) RNA translation. The implication of B12 in the setting of antiviral treatment is unknown. This study aims to retrospectively evaluate the discriminative efficacy of pretreatment B12 serum levels (s-B12) on end-of-treatment response (ETR) in patients with chronic HCV. Ninety-nine treatment naïve HCV patients, treated with interferon and ribavirin were studied. Serum B12 (s-B12) was analysed in samples collected before treatment start. Pretreatment s-B12 levels were correlated to ETR using univariate analysis. S-B12 and clinical data were evaluated in a multivariate logistic regression model. Mean pretreatment s-B12 was 331 pm in ETR and 260 pm in nonresponders (NR) (P = 0.012). In patients with s-B12 levels ≤ 360 pm, 23 (31.5%) were NR and 50 (68.5%) had ETR. In patients with s-B12 > 360 pm, one (3.8%) was NR and 25 (96.2%) had ETR (P = 0.0034). The results of the multivariate analysis were as follows: Pretreatment s-B12 > 360 vs ≤ 360 pm: OR 28.6 CI 2.31-354, P = 0.008. Fibrosis stage 3-4 vs 0-2: OR 0.29 CI 0.074-1.12, P = 0.068. Genotype 2/3 vs 1/4/5: OR 15.5 CI 2.87-83.9, P = 0.0012. Dose reduction vs no dose reduction: OR 0.21, CI 0.048-0.91 P = 0.034. Standard interferon vs pegylated-interferon: OR 0.079, CI 0.0091-0.68 P = 0.019. Age and gender were not correlated to ETR. S-B12 > 360 pm is independently correlated to ETR in HCV patients treated with interferon and ribavirin. This suggests that B12 is involved in suppression of viral replication during anti-HCV treatment.
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Affiliation(s)
- P Rosenberg
- Department of Medicine, Karolinska Institute, Stockholm, Sweden.
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11
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Takeshita M, Ishida YI, Akamatsu E, Ohmori Y, Sudoh M, Uto H, Tsubouchi H, Kataoka H. Proanthocyanidin from blueberry leaves suppresses expression of subgenomic hepatitis C virus RNA. J Biol Chem 2009; 284:21165-76. [PMID: 19531480 DOI: 10.1074/jbc.m109.004945] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Hepatitis C virus (HCV) infection is a major cause of chronic liver disease such as chronic hepatitis, cirrhosis, and hepatocellular carcinoma. While searching for new natural anti-HCV agents in agricultural products, we found a potent inhibitor of HCV RNA expression in extracts of blueberry leaves when examined in an HCV subgenomic replicon cell culture system. This activity was observed in a methanol extract fraction of blueberry leaves and was purified by repeated fractionations in reversed-phase high-performance liquid chromatography. The final purified fraction showed a 63-fold increase in specific activity compared with the initial methanol extracts and was composed only of carbon, hydrogen, and oxygen. Liquid chromatography/mass-ion trap-time of flight analysis and butanol-HCl hydrolysis analysis of the purified fraction revealed that the blueberry leaf-derived inhibitor was proanthocyanidin. Furthermore, structural analysis using acid thiolysis indicated that the mean degree of polymerization of the purified proanthocyanidin was 7.7, consisting predominantly of epicatechin. Proanthocyanidin with a polymerization degree of 8 to 9 showed the greatest potency at inhibiting the expression of subgenomic HCV RNA. Purified proanthocyanidin showed dose-dependent inhibition of expression of the neomycin-resistant gene and the NS-3 protein gene in the HCV subgenome in replicon cells. While characterizing the mechanism by which proanthocyanidin inhibited HCV subgenome expression, we found that heterogeneous nuclear ribonucleoprotein A2/B1 showed affinity to blueberry leaf-derived proanthocyanidin and was indispensable for HCV subgenome expression in replicon cells. These data suggest that proanthocyanidin isolated from blueberry leaves may have potential usefulness as an anti-HCV compound by inhibiting viral replication.
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Affiliation(s)
- Masahiko Takeshita
- Research Division, Minami Nippon Dairy Co-op Co., Ltd., Miyazaki 885-0073, Japan
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12
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Solomon LR. Disorders of cobalamin (Vitamin B12) metabolism: Emerging concepts in pathophysiology, diagnosis and treatment. Blood Rev 2007; 21:113-30. [DOI: 10.1016/j.blre.2006.05.001] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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13
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Haqshenas G, Dong X, Netter H, Torresi J, Gowans EJ. A chimeric GB virus B encoding the hepatitis C virus hypervariable region 1 is infectious in vivo. J Gen Virol 2007; 88:895-902. [PMID: 17325362 DOI: 10.1099/vir.0.82467-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Two GB virus B (GBV-B) chimeric genomes, GBV-HVR and GBV-HVRh (with a hinge), containing the coding region of the immunodominant hypervariable region 1 (HVR1) of the E2 envelope protein of Hepatitis C virus (HCV) were constructed. Immunoblot analysis confirmed that HVR1 was anchored to the GBV-B E2 protein. To investigate the replication competence and in vivo stability of in vitro-generated chimeric RNA transcripts, two naïve marmosets were inoculated intrahepatically with the transcripts. The GBV-HVR chimeric genome was detectable for 2 weeks post-inoculation (p.i.), whereas GBV-HVRh reverted to wild type 1 week p.i. Sequencing analysis of the HVR1 and flanking regions from GBV-HVR RNA isolated from marmoset serum demonstrated that the HVR1 insert remained unaltered in the GBV-HVR chimera for 2 weeks. Inoculation of a naïve marmoset with serum collected at 1 week p.i. also resulted in viraemia and confirmed that the serum contained infectious particles. All animals cleared the infection by 3 weeks p.i. and remained negative for the remaining weeks. The chimera may prove useful for the in vivo examination of any HCV HVR1-based vaccine candidates.
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Affiliation(s)
- G Haqshenas
- The Macfarlane Burnet Institute, GPO Box 2284, Melbourne, VIC 3001, Australia
| | - X Dong
- Department of Microbiology, Monash University, Clayton, VIC 3800, Australia
- The Macfarlane Burnet Institute, GPO Box 2284, Melbourne, VIC 3001, Australia
| | - H Netter
- Department of Microbiology, Monash University, Clayton, VIC 3800, Australia
| | - J Torresi
- Department of Medicine (RMH/WH), University of Melbourne, Centre for Clinical Research Excellence, Royal Melbourne Hospital, Parkville, VIC, Australia
| | - E J Gowans
- Department of Microbiology, Monash University, Clayton, VIC 3800, Australia
- The Macfarlane Burnet Institute, GPO Box 2284, Melbourne, VIC 3001, Australia
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14
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Foloppe N, Matassova N, Aboul-Ela F. Towards the discovery of drug-like RNA ligands? Drug Discov Today 2006; 11:1019-27. [PMID: 17055412 DOI: 10.1016/j.drudis.2006.09.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2006] [Revised: 08/18/2006] [Accepted: 09/04/2006] [Indexed: 10/24/2022]
Abstract
Targeting RNA with small molecule drugs is an area of great potential for therapeutic treatment of infections and possibly genetic and autoimmune diseases. However, a mature set of precedents and established methodology is lacking. The physicochemical properties of RNA raise specific issues and obstacles to development, and contribute to explain the distinct characteristics of natural RNA ligands, including antibiotics. Yet, RNA-targeting strategies are being implemented to reinvigorate antibacterial discovery by using the ribosomal X-ray structures to modify known antibiotics. To exploit further these structures, we suggest the use of existing protein kinase-directed libraries of drug-like compounds to target the A-site of the bacterial ribosome, on the basis of a specific structural hypothesis.
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Affiliation(s)
- Nicolas Foloppe
- Vernalis (R&D) Ltd., Granta Park, Abington, Cambridge, CB1 6GB, UK
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Jang SK. Internal initiation: IRES elements of picornaviruses and hepatitis c virus. Virus Res 2005; 119:2-15. [PMID: 16377015 DOI: 10.1016/j.virusres.2005.11.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2005] [Revised: 08/29/2005] [Accepted: 11/02/2005] [Indexed: 02/08/2023]
Abstract
The scanning hypothesis provides an explanation for events preceding the first peptide bond formation during the translation of the vast majority of eukaryotic mRNAs. However, this hypothesis does not explain the translation of eukaryotic mRNAs lacking the cap structure required for scanning. The existence of a group of positive sense RNA viruses lacking cap structures (e.g. picornaviruses) indicates that host cells also contain a 5' cap-independent translation mechanism. This review discusses the translation mechanisms of atypical viral mRNAs such as picornaviruses and hepatitis c virus, and uses these mechanisms to propose a general theme for all translation, including that of both eukaryotic and prokaryotic mRNAs.
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Affiliation(s)
- Sung Key Jang
- NRL, PBC, Department of Life Science, Division of Molecular and Life Sciences, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
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