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2.
Eur Eat Disord Rev ; 23(4): 312-7, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25988537

ABSTRACT

Women with type 1 diabetes are at high risk for eating disorders (ED), a combination that can increase medical complications and mortality. As little is known about treatment response in this population, clinical presentation and treatment outcome in an extended case series were assessed. A chart review at the Eating Disorders Day Hospital Program at Toronto General Hospital identified a total of 100 individuals with type 1 diabetes assessed 1990-2012. Of 37 who attended day hospital, most experienced improvement in ED symptoms, but only 18.8% had a good immediate treatment outcome, while 43.8% had an intermediate outcome and 37.5% had a poor outcome (meeting diagnostic criteria at discharge). This is poorer than program outcomes in individuals without diabetes (χ(2) = 12.2, df = 2; p = 0.002). Factors influencing treatment engagement and outcome must be further studied and used to improve treatment results in this high-risk group.


Subject(s)
Day Care, Medical , Diabetes Mellitus, Type 1/therapy , Feeding and Eating Disorders/therapy , Adult , Comorbidity , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 1/psychology , Feeding and Eating Disorders/diagnosis , Feeding and Eating Disorders/psychology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Ontario , Retrospective Studies , Risk Factors , Treatment Outcome , Young Adult
3.
Eur Eat Disord Rev ; 23(4): 294-303, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25823423

ABSTRACT

Multi-family therapy (MFT) has yet to be evaluated in families of adults with anorexia nervosa (AN). The study aims were: (i) assess the feasibility of MFT for AN; and, (ii) assess whether MFT is associated with improved outcomes for families compared with single-family therapy (SFT). Adult patients with AN consecutively referred to an eating disorder treatment program were assigned (non-randomly) to receive eight sessions of SFT or MFT. Assessment occurred pre-therapy, immediately post-therapy, and at 3-month follow-up. A total of 37 female patients (13 SFT, 24 MFT) and 45 family members (16 SFT, 29 MFT) completed treatment. There were significant time effects for patients' BMI, eating disorder-related psychopathology and multiple family outcome measures. There were no differences between MFT and SFT on family outcome measures at end of treatment and 3 months post treatment. MFT is a feasible intervention that can be used in adult intensive treatment for those with AN.


Subject(s)
Family Therapy/methods , Psychotherapy, Group/methods , Adolescent , Adult , Anorexia Nervosa/diagnosis , Anorexia Nervosa/psychology , Anorexia Nervosa/therapy , Combined Modality Therapy , Cooperative Behavior , Feasibility Studies , Female , Humans , Interdisciplinary Communication , Middle Aged , Pilot Projects , Surveys and Questionnaires , Treatment Outcome , Young Adult
4.
Artif DNA PNA XNA ; 1(1): 17-26, 2010 Jul.
Article in English | MEDLINE | ID: mdl-21687523

ABSTRACT

Chronic infection with the hepatitis B virus (HBV) occurs in approximately 6% of the world's population and carriers of the virus are at risk for complicating hepatocellular carcinoma. Current treatment options have limited efficacy and chronic HBV infection is likely to remain a significant global medical problem for many years to come. Silencing HBV gene expression by harnessing RNA interference (RNAi) presents an attractive option for development of novel and effective anti HBV agents. However, despite significant and rapid progress, further refinement of existing technologies is necessary before clinical application of RNAi-based HBV therapies is realized. Limiting off target effects, improvement of delivery efficiency, dose regulation and preventing reactivation of viral replication are some of the hurdles that need to be overcome. To address this, we assessed the usefulness of the recently described class of altritol-containing synthetic siRNAs (ANA siRNAs), which were administered as lipoplexes and tested in vivo in a stringent HBV transgenic mouse model. Our observations show that ANA siRNAs are capable of silencing of HBV replication in vivo. Importantly, non specific immunostimulation was observed with unmodified siRNAs and this undesirable effect was significantly attenuated by ANA modification. Inhibition of HBV replication of approximately 50% was achieved without evidence for induction of toxicity. These results augur well for future application of ANA siRNA therapeutic lipoplexes.

5.
J Control Release ; 143(2): 222-32, 2010 Apr 19.
Article in English | MEDLINE | ID: mdl-19969034

ABSTRACT

We report the syntheses of novel cationic lipids comprised of cholesteryl-moieties linked to guanidinium functional groups, and also cationic lipids comprising a dialkylglycylamide moiety conjugated with a polyamine or a guanidinium functional group. In plasmid DNA (pDNA) transfection studies, these cationic lipids were formulated into cationic liposomes with the neutral co-lipid dioleoyl-L-alpha-phosphatidylethanolamine (DOPE) or with a recently reported neutral lipophosphoramidate derivative of histamine (MM27). We observe that cationic liposomes prepared from the cationic lipid N',N'-dioctadecyl-N-4,8-diaza-10-aminodecanoylglycine amide (DODAG) and DOPE frequently mediate the highest levels of transfection in vitro in all three different cell lines studied (OVCAR-3, IGROV-1 and HeLa) both in the presence or absence of serum. In addition, in vitro cellular toxicity was found to be minimal. Alternatively, we observe that DODAG alone forms lipoplex nanoparticles with small interfering RNA (siRNA) that are able to mediate the functional delivery of two previously validated anti-hepatitis B virus (HBV)--siRNAs to murine liver in vivo with minimal observable liver toxicity and immune stimulation. Specific knock-down of HBV infection parameters (virion and hepatic mRNA levels) is observed that is at least equivalent to the impact of extensive treatment with lamivudine (a licensed antiviral drug).


Subject(s)
DNA/administration & dosage , Dipeptides/chemistry , Plasmids/administration & dosage , RNA, Small Interfering/administration & dosage , Transfection , Animals , Cations/chemistry , Cell Line , Cell Survival , Hepatitis B virus/genetics , Humans , Liposomes/chemistry , Mice , Mice, Transgenic , Nanoparticles/chemistry , RNA, Small Interfering/genetics
6.
Toxicol Pathol ; 37(3): 333-42, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19258306

ABSTRACT

The authors investigated the spectrum of tumors and Trp53 mutations in genetically engineered models using the FVB/N mouse that expressed the hepatitis B virus genome and/or carried a Trp53 null and wildtype allele and/or were exposed to aflatoxin B1. Liver tumor incidence was increased when all three risk factors were present. Without aflatoxin B1 exposure, neither Trp53 haploinsufficiency nor HBV expression affected liver tumor development. Liver tumor prevalence increased with aflatoxin B1 exposure (p < .001), as thirteen of fourteen mice with liver tumors were initiated with aflatoxin B1. Liver tumors were more frequent in males (12/190) than females (2/170). Seventy-three mice developed sarcomas. Trp53 haploinsufficiency was associated with increased sarcoma incidence in males and females (p < .001). In Trp53 haploinsufficient mice, the HBV transgene increased the risk of sarcoma in males and females (p < .001). Lymphoma was significantly increased in Trp53 haploinsufficient FVB/N mice. There was no loss of heterozygosity at the wildtype Trp53 locus in twenty-five sarcomas or four hepatocellular tumors examined. No mutations were identified in the mRNA (exons 2-11) of Trp53 in six liver neoplasms or twenty-four sarcomas. In this model system, HBV expression affected only hepatocellular neoplasia in association with both aflatoxin B1 initiation and p53 haploinsufficiency.


Subject(s)
Aflatoxin B1/genetics , Disease Models, Animal , Hepatitis B virus/genetics , Liver Neoplasms, Experimental/genetics , Animals , Female , Genetic Engineering/adverse effects , Hepatitis B Surface Antigens/genetics , Immunohistochemistry , Kaplan-Meier Estimate , Ki-67 Antigen/genetics , Liver Neoplasms, Experimental/chemically induced , Liver Neoplasms, Experimental/pathology , Liver Neoplasms, Experimental/virology , Male , Mice , Mice, Inbred Strains , Mice, Transgenic , Sex Factors , Survival Analysis , Tumor Suppressor Protein p53/genetics
7.
Mol Pharm ; 6(3): 706-17, 2009.
Article in English | MEDLINE | ID: mdl-19159285

ABSTRACT

Harnessing RNA interference (RNAi) to inhibit hepatitis B virus (HBV) gene expression has promising application to therapy. Here we describe a new hepatotropic nontoxic lipid-based vector system that is used to deliver chemically unmodified small interfering RNA (siRNA) sequences to the liver. Anti HBV formulations were generated by condensation of siRNA (A component) with cationic liposomes (B component) to form AB core particles. These core particles incorporate an aminoxy cholesteryl lipid for convenient surface postcoupling of polyethylene glycol (PEG; C component, stealth/biocompatibility polymer) to give triggered PEGylated siRNA-nanoparticles (also known as siRNA-ABC nanoparticles) with uniform small sizes of 80-100 nm in diameter. The oxime linkage that results from PEG coupling is pH sensitive and was included to facilitate acidic pH-triggered release of nucleic acids from endosomes. Nanoparticle-mediated siRNA delivery results in HBV replication knockdown in cell culture and in murine hydrodynamic injection models in vivo. Furthermore repeated systemic administration of triggered PEGylated siRNA-nanoparticles to HBV transgenic mice results in the suppression of markers of HBV replication by up to 3-fold relative to controls over a 28 day period. This compares favorably to silencing effects seen during lamivudine treatment. Collectively these observations indicate that our PEGylated siRNA-nanoparticles may have valuable applications in RNAi-based HBV therapy.


Subject(s)
Hepatitis B virus/genetics , Hepatitis B virus/physiology , Nanoparticles/chemistry , Polyethylene Glycols/chemistry , RNA, Small Interfering/physiology , Virus Replication/physiology , Animals , Cell Line, Tumor , Humans , Injections, Intravenous , Liposomes/chemistry , Mice , Molecular Structure , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/chemistry , RNA, Small Interfering/genetics , Virus Replication/genetics
8.
J Gene Med ; 10(8): 878-89, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18470951

ABSTRACT

BACKGROUND: RNA interference based therapeutic approaches hold promise for the treatment of patients chronically infected with hepatitis B virus (HBV). To conquer HBV infection, long-term suppression of target transcripts in all hepatocytes without toxic effects may be required. The present study explored gene-deleted adenoviral vectors (GD-AdV) lacking all viral coding sequences for delivery of the previously described short hairpin RNA (shRNA) HBVU6no.2, which was demonstrated to result in post-transcriptional knock-down of HBV transcripts. METHODS: We established conditions for shRNA delivery expressed from GD-AdV in vitro and in vivo and observed up to 96% shRNA-mediated knockdown of luciferase expressed in mouse liver. To investigate in vivo efficacy of HBVU6no.2 expressed from a GD-AdV, we explored a transient and a transgenic mouse model for HBV infection. RESULTS: We observed an up to 68% drop in serum HBV surface antigen (HBsAg) levels in the transient and the transgenic mouse model for HBV infection, respectively. Interestingly, we detected an up to 86% drop in HBsAg levels in both animal models after administration of a control GD-AdV encoding beta-galactosidase. In concordance with reduced serum HBsAg levels, we observed reduced HBV replication as demonstrated by Southern blot analysis of HBV genomes. CONCLUSIONS: The present study demonstrates that GD-AdV can be used against HBV infection but the design of DNA sequences including shRNAs contained in the vector and virus-host interactions during superinfection needs to be carefully considered.


Subject(s)
Adenoviridae/genetics , Genetic Therapy/methods , Hepatitis B virus/genetics , Hepatitis B/therapy , RNA, Small Interfering/therapeutic use , Animals , Genetic Vectors , Hepatitis B Surface Antigens/genetics , Mice , Mice, Transgenic , RNA Interference
9.
Hum Gene Ther ; 19(11): 1325-31, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19848584

ABSTRACT

Achieving safe delivery of anti-hepatitis B virus (HBV) RNA interference (RNAi) effectors is an important objective of this gene-silencing technology. Adenoviruses (Ads) have a natural tropism for the liver after systemic administration, and are useful for delivery of expressed anti-HBV RNAi sequences. However, a drawback of Ad vectors is diminished efficacy and toxicity that results from stimulation of innate and adaptive immunity. To attenuate these effects we used monomethoxy polyethylene glycol-succinimidyl propionate (mPEG-SPA) to modify first-generation vectors that express an anti-HBV RNAi effector. Efficient hepatocyte transduction and knockdown of HBV replication were achieved after intravenous administration of 5 x 10(9) PEGylated or native recombinant Ads to HBV transgenic mice. After the first injection, circulating HBV viral particle equivalents (VPEs) remained low for 3 weeks and began to increase after 5 weeks. A second dose of PEGylated anti-HBV Ad caused a less sustained decrease in circulating VPEs, but no silencing after a second dose was observed in animals treated with unmodified vector. Release of inflammatory cytokines, including monocyte chemoattractant protein-1 (MCP-1), interferon-gamma, interleukin-6, and tumor necrosis factor-alpha, was elevated in animals receiving unmodified vectors. However, only a modest increase in MCP-1 was observed in mice that received a second dose of PEG Ads. Also, polymer-conjugated vectors induced a weaker adaptive immune response and were less hepatotoxic than their unmodified counterparts. Collectively, these observations show that PEG modification of Ads expressing RNAi effectors improves their potential for therapeutic application against HBV infection.


Subject(s)
Adenoviridae/genetics , Genetic Vectors , Hepatitis B virus/physiology , Polyethylene Glycols/chemistry , RNA, Small Interfering/physiology , Virus Replication/physiology , Alanine Transaminase/metabolism , Animals , Aspartate Aminotransferases/metabolism , Blotting, Northern , Cytokines/metabolism , Enzyme-Linked Immunosorbent Assay , Mice , Mice, Transgenic , RNA Interference/physiology
10.
Nature ; 441(7092): 537-41, 2006 May 25.
Article in English | MEDLINE | ID: mdl-16724069

ABSTRACT

RNA interference (RNAi) is a universal and evolutionarily conserved phenomenon of post-transcriptional gene silencing by means of sequence-specific mRNA degradation, triggered by small double-stranded RNAs. Because this mechanism can be efficiently induced in vivo by expressing target-complementary short hairpin RNA (shRNA) from non-viral and viral vectors, RNAi is attractive for functional genomics and human therapeutics. Here we systematically investigate the long-term effects of sustained high-level shRNA expression in livers of adult mice. Robust shRNA expression in all the hepatocytes after intravenous infusion was achieved with an optimized shRNA delivery vector based on duplex-DNA-containing adeno-associated virus type 8 (AAV8). An evaluation of 49 distinct AAV/shRNA vectors, unique in length and sequence and directed against six targets, showed that 36 resulted in dose-dependent liver injury, with 23 ultimately causing death. Morbidity was associated with the downregulation of liver-derived microRNAs (miRNAs), indicating possible competition of the latter with shRNAs for limiting cellular factors required for the processing of various small RNAs. In vitro and in vivo shRNA transfection studies implied that one such factor, shared by the shRNA/miRNA pathways and readily saturated, is the nuclear karyopherin exportin-5. Our findings have fundamental consequences for future RNAi-based strategies in animals and humans, because controlling intracellular shRNA expression levels will be imperative. However, the risk of oversaturating endogenous small RNA pathways can be minimized by optimizing shRNA dose and sequence, as exemplified here by our report of persistent and therapeutic RNAi against human hepatitis B virus in vivo.


Subject(s)
MicroRNAs/metabolism , MicroRNAs/toxicity , Nucleic Acid Conformation , RNA/metabolism , RNA/toxicity , Animals , Hepatitis B virus/physiology , Humans , Karyopherins/metabolism , Liver/drug effects , Liver/injuries , Liver/metabolism , Liver/pathology , Liver Regeneration , Mice , Mice, Transgenic , MicroRNAs/genetics , RNA/chemistry , RNA/genetics , RNA Interference , Survival Analysis
11.
Mol Ther ; 13(2): 411-21, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16337206

ABSTRACT

Exploiting the RNA interference pathway has shown promise for developing novel and effective treatment of hepatitis B virus (HBV) infection. To advance this approach, we analyzed the antiviral efficacy of a panel of 10 Pol III U6 promoter-encoded short hairpin RNAs (shRNAs) that target conserved sequences of the oncogenic HBx open reading frame. To facilitate intracellular processing, the shRNAs included mismatches in the 25-bp stem region and a terminal loop of miRNA-23. Two shRNAs (shRNA 5 and shRNA 6) showed knockdown of HBV markers by 80-100% in transfected hepatocytes and also in a murine hydrodynamic injection model of HBV replication. Intracellular processing of hairpin RNA with the intended strand bias correlated with antiviral efficacy. Moreover, markers of HBV replication were inhibited without inducing genes associated with the nonspecific interferon response. To assess the antiviral efficacy of the shRNAs in a context that is similar to natural HBV infection, shRNA-encoding cassettes were tested against the virus in a HBV transgenic murine model. When delivered using recombinant adenovirus vectors, U6 shRNA 5 and U6 shRNA 6 mediated significant HBV knockdown. Collectively, these observations indicate that U6 shRNA 5 and U6 shRNA 6 are promising candidates for therapy of chronic HBV infection.


Subject(s)
Hepatitis B virus/growth & development , RNA Interference , RNA, Antisense/therapeutic use , RNA, Viral/therapeutic use , Trans-Activators/antagonists & inhibitors , Trans-Activators/genetics , Virus Replication/genetics , Adenoviridae/genetics , Animals , Cell Line , Cell Line, Tumor , Genetic Vectors , Hepatitis B virus/genetics , Hepatitis B virus/physiology , Humans , Mice , Mice, Transgenic , Plasmids/genetics , RNA, Viral/antagonists & inhibitors , Viral Regulatory and Accessory Proteins
12.
J Med Virol ; 77(1): 57-65, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16032730

ABSTRACT

Hepatitis B virus (HBV) transgenic mice that replicate HBV in the liver generally do not exhibit gross liver pathology, while maintaining a high level (10(7) or greater) of viral titer in the blood. We have used this model to determine the minimum effects of HBV replication in the liver on cellular gene transcription, using cDNA microarrays. cDNA microarray data from sets of HBV versus control cDNA microarrays revealed a very small impact of HBV on the cellular transcriptome. After deletion of genes that were variable in control cDNA microarrays and applying significance analysis of microarrays (SAM), an application to detect statistically significantly regulated genes, we identified 18 upregulated genes and 14 downregulated genes. Most of the regulated genes show a change in expression with respect to control of less than 40% in either direction, demonstrating small effects of HBV. The largest functional category for upregulated genes was lipid biosynthesis, in which ATP citrate lyase, fatty acid synthase, sterol regulatory element binding factor 2, and retinol binding protein 1 were all upregulated. The most strongly downregulated genes were in the cytochrome p450 group, particularly p450, 4a14. Several growth regulatory genes including cyclin D1, IGF binding protein 3, and PCNA were moderately upregulated. These data are the first to specifically identify enzymes involved in fatty acid and NADPH-electron transport pathways that are altered by the presence of HBV. The data also demonstrates that HBV is well adapted to non-cytopathic replication in hepatocytes. Cellular genes expected to be affected by viral secretion from membranes are clearly upregulated, and upregulation of growth regulatory genes may facilitate replacement of dying hepatocytes during persistent infection.


Subject(s)
Hepatitis B virus/genetics , Lipids/biosynthesis , Liver/metabolism , Oligonucleotide Array Sequence Analysis , Animals , DNA, Complementary/analysis , Disease Models, Animal , Hepatitis B/genetics , Hepatitis B/immunology , Hepatitis B/virology , Hepatitis B virus/immunology , Hepatitis B virus/pathogenicity , Hepatitis B virus/physiology , Liver/virology , Mice , Mice, Transgenic
13.
J Clin Invest ; 112(3): 407-14, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12897208

ABSTRACT

Hepatitis delta virus (HDV) can dramatically worsen liver disease in patients coinfected with hepatitis B virus (HBV). No effective medical therapy exists for HDV. The HDV envelope requires HBV surface antigen proteins provided by HBV. Once inside a cell, however, HDV can replicate its genome in the absence of any HBV gene products. In vitro, HDV virion assembly is critically dependent on prenyl lipid modification, or prenylation, of its nucleocapsid-like protein large delta antigen. To overcome limitations of current animal models and to test the hypothesis that pharmacologic prenylation inhibition can prevent the production of HDV virions in vivo, we established a convenient mouse-based model of HDV infection capable of yielding viremia. Such mice were then treated with the prenylation inhibitors FTI-277 and FTI-2153. Both agents were highly effective at clearing HDV viremia. As expected, HDV inhibition exhibited duration-of-treatment dependence. These results provide the first preclinical data supporting the in vivo efficacy of prenylation inhibition as a novel antiviral therapy with potential application to HDV and a wide variety of other viruses.


Subject(s)
Hepatitis Delta Virus/drug effects , Methionine/analogs & derivatives , Protein Prenylation/drug effects , Alkyl and Aryl Transferases/antagonists & inhibitors , Animals , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Disease Models, Animal , Drug Design , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Farnesyltranstransferase , Hepatitis B/complications , Hepatitis B Surface Antigens/genetics , Hepatitis D/complications , Hepatitis D/drug therapy , Hepatitis D/virology , Hepatitis Delta Virus/genetics , Hepatitis Delta Virus/physiology , Humans , Methionine/chemistry , Methionine/pharmacology , Mice , Mice, Transgenic , Oligopeptides/chemistry , Oligopeptides/pharmacology , RNA Editing , Viremia/drug therapy , Virus Replication/drug effects
14.
Antimicrob Agents Chemother ; 47(8): 2624-35, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12878529

ABSTRACT

This study was designed to test the efficacy of antiviral treatment with entecavir (ETV) in combination with DNA vaccines expressing duck hepatitis B virus (DHBV) antigens as a therapy for persistent DHBV infection in ducks. Ducks were inoculated with 10(9) DHBV genomes at 7 days of age, leading to widespread infection of the liver and viremia within 7 days, and were then treated orally with either ETV (0.1 mg/kg of body weight/day) or distilled water from 21 days posthatch for 244 days. Treatment with ETV caused a 4-log drop in serum DHBV DNA levels within 80 days and a slower 2- to 3-log drop in serum DHBV surface antigen (DHBsAg) levels within 120 days. Following withdrawal of ETV, levels of serum DHBV DNA and DHBsAg rebounded to match those in the water-treated animals within 40 days. Sequential liver biopsy samples collected throughout the study showed that ETV treatment reduced DHBV DNA replicative intermediates 70-fold in the liver, while the level of the stable, template form, covalently closed circular DNA decreased only 4-fold. ETV treatment reduced both the intensity of antigen staining and the percentage of antigen-positive hepatocytes in the liver, but the intensity of antigen staining in bile duct cells appeared not to be effected. Intramuscular administration of five doses of a DNA vaccine expressing the DHBV presurface, surface, precore, and core antigens, both alone and concurrently with ETV treatment, on days 50, 64, 78, 127, and 141 did not result in any significant effect on viral markers.


Subject(s)
Antiviral Agents/therapeutic use , Ducks/virology , Guanine/analogs & derivatives , Guanine/therapeutic use , Hepatitis B Virus, Duck/immunology , Hepatitis, Viral, Animal/therapy , Vaccines, DNA/therapeutic use , Viral Hepatitis Vaccines/therapeutic use , Animals , Combined Modality Therapy , DNA, Viral/blood , DNA, Viral/metabolism , Hepatitis B Surface Antigens/blood , Hepatitis, Viral, Animal/drug therapy , Hepatitis, Viral, Animal/immunology , Hepatocytes/metabolism , Hepatocytes/virology , Liver/metabolism , Liver/pathology , Liver/virology , Liver Function Tests , Vaccination , Virus Replication/drug effects
15.
Nat Biotechnol ; 21(6): 639-44, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12740585

ABSTRACT

Hepatitis B virus (HBV) infection substantially increases the risk of chronic liver disease and hepatocellular carcinoma in humans. RNA interference (RNAi) of virus-specific genes has emerged as a potential antiviral mechanism. Here we show that RNAi can be applied to inhibit production of HBV replicative intermediates in cell culture and in immunocompetent and immunodeficient mice transfected with an HBV plasmid. Cotransfection with plasmids expressing short hairpin RNAs (shRNAs) homologous to HBV mRNAs induced an RNAi response. Northern and Southern analyses of mouse liver RNA and DNA showed substantially reduced levels of HBV RNAs and replicated HBV genomes upon RNAi treatment. Secreted HBV surface antigen (HBsAg) was reduced by 94.2% in cell culture and 84.5% in mouse serum, whereas immunohistochemical detection of HBV core antigen (HBcAg) revealed >99% reduction in stained hepatocytes upon RNAi treatment. Thus, RNAi effectively inhibited replication initiation in cultured cells and mammalian liver, showing that such an approach could be useful in the treatment of viral diseases.


Subject(s)
Hepatitis B virus/drug effects , Hepatitis B virus/growth & development , RNA Interference , RNA, Double-Stranded/pharmacology , RNA, Viral/pharmacology , Virus Replication/drug effects , Animals , Cell Line , Female , Gene Expression Regulation, Viral/genetics , Hepatitis B Core Antigens/biosynthesis , Hepatitis B Core Antigens/drug effects , Hepatitis B virus/genetics , Liver/drug effects , Liver/virology , Mice , Mice, Inbred BALB C/genetics , Mice, Inbred C57BL/genetics , Mice, Inbred NOD/genetics , Virus Replication/genetics
16.
J Virol ; 76(20): 10465-72, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12239323

ABSTRACT

Hepatitis delta virus (HDV) causes both acute and chronic liver disease throughout the world. Effective medical therapy is lacking. Previous work has shown that the assembly of HDV virus-like particles (VLPs) could be abolished by BZA-5B, a compound with farnesyltransferase inhibitory activity. Here we show that FTI-277, another farnesyltransferase inhibitor, prevented the production of complete, infectious HDV virions of two different genotypes. Thus, in spite of the added complexity and assembly determinants of infectious HDV virions compared to VLPs, the former are also sensitive to pharmacological prenylation inhibition. Moreover, production of HDV genotype III virions, which is associated with particularly severe clinical disease, was as sensitive to prenylation inhibition as was that of HDV genotype I virions. Farnesyltransferase inhibitors thus represent an attractive potential class of novel antiviral agents for use against HDV, including the genotypes associated with most severe disease.


Subject(s)
Alkyl and Aryl Transferases/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Hepatitis Delta Virus/drug effects , Methionine/analogs & derivatives , Methionine/pharmacology , Protein Prenylation/drug effects , Virus Assembly/drug effects , Cells, Cultured , Farnesyltranstransferase , Hepatitis Delta Virus/physiology , Hepatocytes/cytology , Hepatocytes/virology , Humans , Tumor Cells, Cultured , Virion , Virus Replication
17.
Antimicrob Agents Chemother ; 46(1): 82-8, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11751115

ABSTRACT

The ability of entecavir (ETV) to inhibit Duck hepatitis B virus (DHBV) infection in duck hepatocytes and ducklings was examined using lamivudine (3TC) as a comparator drug. ETV exhibited antiviral activity (50% effective concentration [EC(50)], 0.13 nM) in DHBV-infected duck hepatocytes that was >1,000-fold more potent than that of 3TC (EC(50), 138 nM). A 21-day treatment of ducklings with 1 mg of ETV per kg of body weight per day by oral gavage resulted in a mean reduction of log(10) 3.1 in serum DHBV DNA levels. Daily treatment with 0.1 mg of ETV/kg was nearly as effective, achieving an average viral DNA level decrease of log(10) 2.1. Reducing the daily dose of ETV to only 0.01 mg/kg resulted in an average viral DNA level decrease of log(10) 0.97. Daily treatment with 25 mg of 3TC/kg resulted in an average viral DNA level decrease of log(10) 0.66, compared to the log(10) 0.20 drop seen for ducklings given the vehicle alone. ETV was also more effective in decreasing the DHBV DNA levels in duck livers after 21 days of treatment, causing average drops of log(10) 1.41, log(10) 0.76, and log(10) 0.26 for dose levels of 1.0, 0.1, and 0.01 mg/kg, respectively, compared to a decrease of log(10) 0.06 for 3TC at a dose level of 25 mg/kg. Levels of viral covalently closed circular DNA in the treatment group receiving 1 mg of ETV/kg were reduced compared to those in the vehicle-treated group. ETV and 3TC were both well tolerated in all treated animals. These results show that ETV is a highly potent and effective antiviral in the DHBV duck model.


Subject(s)
Antiviral Agents/therapeutic use , Guanine/analogs & derivatives , Guanine/therapeutic use , Hepatitis B/drug therapy , Animals , Antiviral Agents/adverse effects , DNA, Viral , Disease Models, Animal , Drug Tolerance , Ducks , Guanine/adverse effects , Hepatitis B virus/drug effects , Hepatocytes/drug effects , Hepatocytes/virology , Treatment Outcome
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