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1.
Hepatology ; 56(4): 1231-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22487892

RESUMO

UNLABELLED: Because the current interferon (IFN)-based treatment for hepatitis C virus (HCV) infection has a therapeutic limitation and side effects, a more efficient therapeutic strategy is desired. Recent studies show that supplementation of vitamin D significantly improves sustained viral response via IFN-based therapy. However, mechanisms and an active molecular form of vitamin D for its anti-HCV effects have not been fully clarified. To address these questions, we infected HuH-7 cells with cell culture-generated HCV in the presence or absence of vitamin D(3) or its metabolites. To our surprise, 25-hydroxyvitamin D(3) [25(OH)D(3) ], but not vitamin D(3) or 1,25-dihydroxyvitamin D(3) , reduced the extra- and intracellular levels of HCV core antigen in a concentration-dependent manner. Single-cycle virus production assay with a CD81-negative cell line reveals that the inhibitory effect of 25(OH)D(3) is at the level of infectious virus assembly but not entry or replication. Long-term 25(OH)D(3) treatment generates a HCV mutant with acquired resistance to 25(OH)D(3) , and this mutation resulting in a N1279Y substitution in the nonstructural region 3 helicase domain is responsible for the resistance. CONCLUSION: 25(OH)D(3) is a novel anti-HCV agent that targets an infectious viral particle assembly step. This finding provides insight into the improved efficacy of anti-HCV treatment via the combination of vitamin D(3) and IFN. Our results also suggest that 25(OH)D(3) , not vitamin D(3) , is a better therapeutic option in patients with hepatic dysfunction and reduced enzymatic activity for generation of 25(OH)D(3) .


Assuntos
Antivirais/farmacologia , Calcifediol/farmacologia , Proliferação de Células/efeitos dos fármacos , Colecalciferol/farmacologia , Hepacivirus/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Hepacivirus/crescimento & desenvolvimento , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/imunologia , Humanos , Interferon alfa-2 , Interferon-alfa/farmacologia , Polietilenoglicóis/farmacologia , Reação em Cadeia da Polimerase/métodos , RNA Viral/efeitos dos fármacos , RNA Viral/metabolismo , Proteínas Recombinantes/farmacologia , Ribavirina/farmacologia , Estudos de Amostragem , Sensibilidade e Especificidade
2.
Gastroenterology ; 137(2): 673-81, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19394333

RESUMO

BACKGROUND & AIMS: Hepatitis C virus (HCV) gains entry into susceptible cells by interacting with cell surface receptor(s). Viral entry is an attractive target for antiviral development because of the highly conserved mechanism. METHODS: HCV culture systems were used to study the effects of phosphorothioate oligonucleotides (PS-ONs), as amphipathic DNA polymers (APs), on HCV infection. The in vivo effects of APs were tested in urokinase plasminogen activator (uPA)/severe combined immunodeficient (SCID) mice engrafted with human hepatocytes. RESULTS: We show the sequence-independent inhibitory effects of APs on HCV infection. APs were shown to potently inhibit HCV infection at submicromolar concentrations. APs exhibited a size-dependent antiviral activity and were equally active against HCV pseudoparticles of various genotypes. Control phosphodiester oligonucleotide (PO-ON) polymer without the amphipathic structure was inactive. APs had no effect on viral replication in the HCV replicon system or binding of HCV to cells but inhibited viral internalization, indicating that the target of inhibition is at the postbinding, cell entry step. In uPA/SCID mice engrafted with human hepatocytes, APs efficiently blocked de novo HCV infection. CONCLUSIONS: Our results demonstrate that APs are a novel class of antiviral compounds that hold promise as a drug to inhibit HCV entry.


Assuntos
DNA/farmacologia , Hepatite C/tratamento farmacológico , Oligonucleotídeos Fosforotioatos/farmacologia , Polímeros/farmacologia , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/farmacologia , Sítios de Ligação , Células Cultivadas , DNA Viral/genética , DNA Viral/metabolismo , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Hepacivirus/fisiologia , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Camundongos , Camundongos SCID , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Oligonucleotídeos Fosforotioatos/metabolismo , Sensibilidade e Especificidade , Transfecção , Ligação Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
3.
J Gastroenterol ; 54(5): 449-458, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30684016

RESUMO

BACKGROUND: The emergence of a deletion mutant at hepatitis C virus (HCV) NS5A-P32 (P32del) has recently been reported in a subset of chronic hepatitis C patients who experience virologic failure after direct-acting antiviral drug (DAA) treatment. This mutation confers extremely high resistance to NS5A inhibitors. No effective treatment has been established for cases with this mutation. METHODS: We used a JFH1-based recombinant virus with NS5A from a genotype 1b strain to introduce a P32del mutation. We inoculated human hepatocyte chimeric mice with sera from a patient with ledipasvir/sofosbuvir therapy failure carrying a genotype 1b HCV with NS5A L31M and P32del or from a DAA-naïve patient carrying wild-type virus. RESULTS: JFH1-based chimeric viruses with P32del showed sufficient levels of replication for in vitro assay despite the suppression of viral growth and infectious virus production. Variants with P32del exhibited severe resistance to all tested NS5A inhibitors, including daclatasvir, ledipasvir, elbasvir and velpatasvir, but were as susceptible to NS3/4A inhibitors, NS5B inhibitors, interferon alfa-2b, and ribavirin as wild-type viruses in the in vitro assay. The P32del mutant virus caused persistent infection in all inoculated chimeric mice with high viral titer and frequency. The virus was resistant to the ledipasvir/GS-558093 (a nucleotide analog inhibitor of NS5B polymerase) regimen but susceptible to either simeprevir plus GS-558093 or peg-interferon alfa-2b, compared to the wild-type virus. CONCLUSION: Therapies combining at least two drugs among NS3/4A inhibitors, NS5B inhibitors and non-selective antiviral agents may be effective for HCV-infected patients with NS5A-P32del.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Proteínas não Estruturais Virais/genética , Idoso , Animais , Antivirais/farmacologia , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Benzofuranos/farmacologia , Carbamatos/farmacologia , Linhagem Celular , Quimera , Farmacorresistência Viral/genética , Quimioterapia Combinada , Fluorenos/farmacologia , Fluorenos/uso terapêutico , Guanosina Monofosfato/análogos & derivados , Guanosina Monofosfato/farmacologia , Guanosina Monofosfato/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatócitos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Imidazóis/farmacologia , Interferon alfa-2/farmacologia , Interferon alfa-2/uso terapêutico , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Masculino , Camundongos , Pessoa de Meia-Idade , Polietilenoglicóis/farmacologia , Polietilenoglicóis/uso terapêutico , Pirrolidinas , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Ribavirina/farmacologia , Deleção de Sequência , Serina Proteases , Simeprevir/farmacologia , Simeprevir/uso terapêutico , Valina/análogos & derivados , Proteínas não Estruturais Virais/antagonistas & inibidores
4.
PLoS One ; 8(5): e63672, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23717463

RESUMO

OBJECTIVE: 1,25(OH)2 vitamin D3 can affect immune cells. However, the mechanism responsible for the favorable effects of 1(OH) vitamin D3, which becomes 1,25(OH)2 vitamin D3 in the liver, is not clear. The aim of this study is to analyze the immunological response of 1(OH) vitamin D3 supplementation in CH-C patients. DESIGN: Forty-two CH-C patients were treated with 1(OH) vitamin D3/Peg-IFNα/RBV. Forty-two case-matched controls were treated with Peg-IFNα/RBV. The expression of Interferon-stimulated genes (ISGs)-mRNA in the liver biopsy samples and JFH-1 replicating Huh-7 cells were quantified by real-time PCR. Ten kinds of cytokines in the plasma were quantified during treatment by using a suspension beads array. A trans-well co-culture system with peripheral blood mononuclear cells (PBMCs) and Huh-7 cells was used to analyze the effect of 1(OH) vitamin D3. The activities of the Th1 response were compared between subjects treated with 1(OH) vitamin D3/Peg-IFN/RBV and those treated with Peg-IFN/RBV therapy alone. RESULTS: 1(OH) vitamin D3/Peg-IFN/RBV treatment could induce rapid viral reduction, especially in IL28B T/T polymorphism. Several kinds of cytokines including IP-10 were significantly decreased after 4 weeks of 1(OH) vitamin D3 treatment (p<0.05). Th1 responses in the subjects treated with 1(OH) vitamin D3/Peg-IFN/RBV were significantly higher than those treated with Peg-IFN/RBV at 12 weeks after Peg-IFN/RBV therapy (p<0.05). The expression of ISGs in the patient's liver biopsy samples was significantly lower than in those treated without 1(OH) vitamin D3 (p<0.05). CONCLUSION: 1(OH) vitamin D3 could improve the sensitivity of Peg-IFN/RBV therapy on HCV-infected hepatocytes by reducing the IP-10 production from PBMCs and ISGs expression in the liver.


Assuntos
Antivirais/uso terapêutico , Calcifediol/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Idoso , Antivirais/farmacologia , Calcifediol/farmacologia , Linhagem Celular Tumoral , Citocinas/sangue , Citocinas/genética , Suplementos Nutricionais , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Expressão Gênica/efeitos dos fármacos , Hepatite C Crônica/imunologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Imunidade Celular/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Ribavirina/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Resultado do Tratamento
5.
J Med Virol ; 73(4): 516-21, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15221894

RESUMO

Clinical lines of evidence have been accumulated that hepatitis B virus (HBV) genotypes have characteristic geographical distributions and distinct clinical impact on liver diseases. The distribution of HBV genotypes was determined with reference to hepatitis B e antigen (HBeAg) and alanine aminotransferase (ALT) levels in 165 patients with hepatitis B in San Francisco. HBV genotypes were determined by enzyme-linked immunosorbent assay (ELISA) and the unclassified samples were sequenced within the S region for phylogenetic analysis. Genotype A occurred in 60 (36%) patients, B in 16 (10%), C in 56 (34%), D in 19 (12%), E in 1 (1%), F in 1 (1%), G in 8 (5%), and H in 4 (2%). Caucasians were infected predominantly with HBV genotype A (HBV/A) (38 of 57 [67%]), Asians with HBV/C (45 of 63 [71%]), and Hispanics with HBV/F and HBV/H (4 of 9 [44%]). Serum ALT levels were higher in the patients infected with HBV/A (P = 0.03) or HBV/G (P = 0.02) than HBV/C. HBeAg was more frequent in patients infected with HBV/G than HBV/C or HBV/D (7 of 8 [88%] vs. 25 of 56 [45%] or 6 of 19 [32%], P = 0.03 or 0.01). In conclusion, eight genotypes (A-H) were identified in San Francisco in association with various ethnicities and then influenced ALT levels as well as the prevalence of serum HBeAg. HBV genotype H might be identified by combination of preS2 serotpe bksf and HBsAg serotype adw.


Assuntos
Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite B Crônica , Adulto , Etnicidade , Feminino , Genótipo , Antígenos de Superfície da Hepatite B/análise , Antígenos de Superfície da Hepatite B/imunologia , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/etnologia , Hepatite B Crônica/fisiopatologia , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Dente Molar , Dados de Sequência Molecular , Filogenia , Prevalência , Precursores de Proteínas , São Francisco/epidemiologia , São Francisco/etnologia , Análise de Sequência de DNA , Sorotipagem , Índice de Gravidade de Doença
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