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2.
Am J Gastroenterol ; 113(6): 863-871, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29695828

RESUMEN

OBJECTIVES: Although direct-acting antiviral regimens have dramatically improved the treatment of hepatitis C virus (HCV) infection, there is some evidence that black race may be an independent predictor of treatment failure. We report a retrospective analysis of black participants receiving elbasvir/grazoprevir (EBR/GZR) in nine phase 2/3 clinical trials. METHODS: Black participants with chronic HCV genotype 1 or 4 (GT1 or GT4) infection who received EBR 50 mg/GZR 100 mg once daily for 12 weeks, or in combination with ribavirin for 16 weeks, were included. The primary end point was sustained virologic response 12 weeks after completion of therapy (SVR12, HCV RNA < 15 IU/mL). RESULTS: Compared with nonblack participants (n = 1310), black participants (n = 332) were more likely to have chronic kidney disease stage 4/5 (9.2% vs. 31.0%, respectively), while other comorbidities were similar between the groups. In black and nonblack participants receiving EBR/GZR for 12 weeks, SVR12 rates were 93.7% (282/301) and 94.2% (1072/1138) in those with GT1 infection, and 93.8% (15/16) and 94.6% (88/93) in those with GT4 infection. SVR12 was 100.0% (15/15) in black participants and 97.5% (77/79) in nonblack participants with GT1 infection receiving EBR/GZR plus ribavirin for 16 weeks. Rates of drug-related adverse events (AEs) were 30% vs. 36.6%, and serious AEs were 7.6% vs. 3.4% in black and nonblack participants, respectively. CONCLUSION: EBR/GZR showed high efficacy in black participants with HCV GT1 or GT4 infection and was generally well tolerated, with a safety profile similar to that reported overall in phase 2/3 clinical trials.


Asunto(s)
Antivirales/uso terapéutico , Benzofuranos/uso terapéutico , Negro o Afroamericano/estadística & datos numéricos , Hepatitis C Crónica/tratamiento farmacológico , Imidazoles/uso terapéutico , Quinoxalinas/uso terapéutico , Ribavirina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Combinación de Medicamentos , Quimioterapia Combinada , Femenino , Genotipo , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , ARN Viral/aislamiento & purificación , Estudios Retrospectivos , Respuesta Virológica Sostenida , Insuficiencia del Tratamiento , Adulto Joven
3.
Surgery ; 163(3): 612-616, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29370927

RESUMEN

BACKGROUND: Sources of liver transplant disparities are not understood adequately, particularly in terms of race and region. METHODS: Fixed effects multivariate logistic regression augmented by modified forward and backward stepwise regression of transplanted patients from the United Network for Organ Sharing Standard Transplant Analysis and Research database (1985-2016) was performed to assess causal inference of such disparities. RESULTS: In the study sample (N = 258,602), significant disparities in the odds of receiving a liver were found: African Americans odds ratio 1.12 (95% confidence interval, 1.08-1.17), Asians 1.12 (95% confidence interval, 1.07-1.18), females 0.80 (95% confidence interval, 0.78-0.83), and malignancy 1.18 (95% confidence interval, 1.13-1.22). Region 7 (IL, MN, ND, SD, and WI) was set as the reference level since its transplantation rate most closely approximated the sex and race-matched rate of the national post-Share 35 average. Significant racial disparities by region were identified using Caucasian Region 7 as the reference: Hispanic Region 9 (New York, West Vermont) 1.22 (1.02-1.45), Hispanic Region 1 (New England) 1.26 (1.01-1.57), Hispanic Region 4 (Oklahoma, TX) 1.23 (1.05-1.43), and Asian Region 4 (Oklahoma, TX) 1.35 (1.05-1.73). CONCLUSION: Despite numerous adjustments to liver allocation, we identified with causal inference statistics on a large dataset spanning ≥30 years there remain racial and regional overweighting.


Asunto(s)
Etnicidad/estadística & datos numéricos , Disparidades en Atención de Salud/etnología , Trasplante de Hígado , Obtención de Tejidos y Órganos , Población Blanca/estadística & datos numéricos , Adulto , Anciano , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estados Unidos , Listas de Espera
4.
Sci Rep ; 7(1): 9223, 2017 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-28835697

RESUMEN

The mechanism of how chronic hepatitis C virus (HCV) infection leads to such a high rate of hepatocellular carcinoma (HCC) is unknown. We found that the PERK axis of endoplasmic reticulum (ER) stress elicited prominent nuclear translocation of Nrf2 in 100% of HCV infected hepatocytes. The sustained nuclear translocation of Nrf2 in chronically infected culture induces Mdm2-mediated retinoblastoma protein (Rb) degradation. Silencing PERK and Nrf2 restored Mdm2-mediated Rb degradation, suggesting that sustained activation of PERK/Nrf2 axis creates oncogenic stress in chronically infected HCV culture model. The activation of Nrf2 and its nuclear translocation were prevented by ER-stress and PERK inhibitors, suggesting that PERK axis is involved in the sustained activation of Nrf2 signaling during chronic HCV infection. Furthermore, we show that HCV clearance induced by interferon-α based antiviral normalized the ER-stress response and prevented nuclear translocation of Nrf2, whereas HCV clearance by DAAs combination does neither. In conclusion, we report here a novel mechanism for how sustained activation of PERK axis of ER-stress during chronic HCV infection activates oncogenic Nrf2 signaling that promotes hepatocyte survival and oncogenesis by inducing Mdm2-mediated Rb degradation.


Asunto(s)
Hepatitis C Crónica/metabolismo , Hepatitis C Crónica/virología , Factor 2 Relacionado con NF-E2/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína de Retinoblastoma/metabolismo , Transducción de Señal , eIF-2 Quinasa/metabolismo , Transporte Activo de Núcleo Celular , Línea Celular , Células Cultivadas , Estrés del Retículo Endoplásmico , Silenciador del Gen , Inestabilidad Genómica , Hepatitis C Crónica/patología , Hepatocitos/metabolismo , Hepatocitos/virología , Humanos , Inmunohistoquímica , Proteolisis , Especies Reactivas de Oxígeno/metabolismo , Replicación Viral
5.
HPB (Oxford) ; 19(9): 793-798, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28647164

RESUMEN

BACKGROUND: Racial disparity in access to liver transplantation among African Americans (AA) compared to Caucasians (CA) has been well described. The aim of this investigation was to examine the presentation of AA liver transplant recipients in a socioeconomically challenged region. METHODS: 680 adult liver transplant candidates and 233 resultant recipients between 2007 and 2015 were analyzed using univariate and multivariate analyses to evaluate factors significant for transplantation. RESULTS: Percentages of wait list patients transplanted were similar between CA and AA (34.9% vs. 32.2%, p = 0.5205). AA were younger (50.4 ± 1.8 vs. 56.3 ± 0.7 yrs, p = 0.0003) with higher average MELD scores (22.9 ± 1.6 vs. 19.4 ± 0.7, p = 0.0230). Overall patient mortality was similar (AA 22.7% vs. CA 26.3%, p = 0.5931). A multiple linear regression showed that male gender was strongly associated with transplantation. CONCLUSIONS: Equal access to liver transplantation remains challenging for racial minorities. At our institution, AA were accepted and transplanted at an equivalent rate as CA despite a higher AA population, HCV rate and diagnosed HCC. AA were younger and sicker at the time of transplant, but overall had similar outcomes compared to CA. Our study highlights the need for studies to delineate the underpinnings of disparity in transplantation access.


Asunto(s)
Negro o Afroamericano , Enfermedad Hepática en Estado Terminal/cirugía , Accesibilidad a los Servicios de Salud , Disparidades en Atención de Salud/etnología , Trasplante de Hígado/métodos , Evaluación de Procesos, Atención de Salud , Población Blanca , Factores de Edad , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/etnología , Enfermedad Hepática en Estado Terminal/mortalidad , Femenino , Supervivencia de Injerto , Humanos , Estimación de Kaplan-Meier , Modelos Lineales , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Nueva Orleans/epidemiología , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores Sexuales , Factores de Tiempo , Resultado del Tratamiento , Listas de Espera
6.
Hepatol Commun ; 1(3): 256-269, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-29404458

RESUMEN

The mechanism why hepatitis C virus (HCV) clearance by direct-acting antivirals (DAAs) does not eliminate the risk of hepatocellular carcinoma (HCC) among patients with advanced cirrhosis is unclear. Many viral and bacterial infections degrade p53 in favor of cell survival to adapt an endoplasmic reticulum (ER)-stress response. In this study, we examined whether HCV clearance by interferon-alpha or DAAs normalizes the ER stress and restores the expression of p53 tumor suppressor in cell culture. We found that HCV infection induces chronic ER stress and unfolded protein response in untransformed primary human hepatocytes. The unfolded protein response induces chaperone-mediated autophagy (CMA) in infected primary human hepatocytes and Huh-7.5 cells that results in degradation of p53 and induced expression of mouse double minute 2 (Mdm2). Inhibition of p53/Mdm2 interactions by small molecule (nutlin-3) or silencing Mdm2 did not rescue the p53 degradation, indicating that HCV infection induces degradation of p53 independent of the Mdm2 pathway. Interestingly, we found that HCV infection degrades p53 in a lysosome-dependent mechanism because lysosome-associated membrane protein 2A silencing restored p53 degradation. Our results show that HCV clearance induced by interferon-alpha-based antiviral therapies normalizes the ER-stress response and restores p53, whereas HCV clearance by DAAs does neither. We show that decreased expression of p53 in HCV-infected cirrhotic liver is associated with expression of chaperones associated with ER stress and the CMA response. Conclusion: HCV-induced ER stress and CMA promote p53 degradation in advanced liver cirrhosis. HCV clearance by DAAs does not restore p53, which provides a potential explanation for why a viral cure by DAAs does not eliminate the HCC risk among patients with advanced liver disease. We propose that resolving the ER-stress response is an alternative approach to reducing HCC risk among patients with cirrhosis after viral cure. (Hepatology Communications 2017;1:256-269).

7.
Viruses ; 8(5)2016 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-27223299

RESUMEN

Hepatitis C virus (HCV) infection frequently leads to chronic liver disease, liver cirrhosis and hepatocellular carcinoma (HCC). The molecular mechanisms by which HCV infection leads to chronic liver disease and HCC are not well understood. The infection cycle of HCV is initiated by the attachment and entry of virus particles into a hepatocyte. Replication of the HCV genome inside hepatocytes leads to accumulation of large amounts of viral proteins and RNA replication intermediates in the endoplasmic reticulum (ER), resulting in production of thousands of new virus particles. HCV-infected hepatocytes mount a substantial stress response. How the infected hepatocyte integrates the viral-induced stress response with chronic infection is unknown. The unfolded protein response (UPR), an ER-associated cellular transcriptional response, is activated in HCV infected hepatocytes. Over the past several years, research performed by a number of laboratories, including ours, has shown that HCV induced UPR robustly activates autophagy to sustain viral replication in the infected hepatocyte. Induction of the cellular autophagy response is required to improve survival of infected cells by inhibition of cellular apoptosis. The autophagy response also inhibits the cellular innate antiviral program that usually inhibits HCV replication. In this review, we discuss the physiological implications of the HCV-induced chronic ER-stress response in the liver disease progression.


Asunto(s)
Autofagia , Estrés del Retículo Endoplásmico , Hepacivirus/fisiología , Hepatitis C/patología , Interacciones Huésped-Patógeno , Respuesta de Proteína Desplegada , Replicación Viral , Animales , Humanos , Ratones SCID
8.
Hepat Med ; 8: 9-20, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26955295

RESUMEN

Autophagy is an intracellular lysosomal degradation process performed by the cells to maintain energy balance. The autophagy response plays an important role in the progression of liver disease due to hepatitis virus infection, alcoholic liver disease, nonalcoholic fatty liver disease, liver cirrhosis, and hepatocellular carcinoma (HCC). An increased autophagy response also contributes to the pathogenesis of liver disease through modulation of innate and adaptive immune responses; a defective cellular autophagy response leads to the development of HCC. Recent progress in the field indicates that autophagy modulation provides a novel targeted therapy for human liver cancer. The purpose of this review is to update our understanding of how the cellular autophagy response impacts the pathophysiology of liver disease and HCC treatment.

9.
Am J Pathol ; 186(4): 938-51, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26896692

RESUMEN

The single nucleotide polymorphism located within the IFNL3 (also known as IL28B) promoter is one of the host factors associated with hepatitis C virus (HCV) clearance by interferon (IFN)-α therapy; however the mechanism remains unknown. We investigated how IL28B gene polymorphism influences HCV clearance with infected primary human hepatocytes, liver biopsies, and hepatoma cell lines. Our study confirms that the rs12979860-T/T genotype has a strong correlation with ss469415590-ΔG/ΔG single nucleotide polymorphism that produces IFN-λ4 protein. We found that IFN-α and IFN-λ1 antiviral activity against HCV was impaired in IL28B T/T infected hepatocytes compared with C/C genotype. Western blot analysis showed that IL28B TT genotype hepatocytes expressed higher levels of IFN-λ proteins (IL28B, IL-29), preactivated IFN-stimulated gene (ISG) expression, and impaired Stat phosphorylation when stimulated with either IFN-α or IFN-λ1. Furthermore, we showed that silencing IFN-λ1 in T/T cell line reduced basal ISG expression and improved antiviral activity. Likewise, overexpression of IFN-λ (1 to 4) in C/C cells induced basal ISG expression and prevented IFN-α antiviral activity. We showed that IFN-λ4, produced at low level only in T/T cells induced expression of IL28B and IL-29 and prevented IFN-α antiviral activity in HCV cell culture. Our results suggest that IFN-λ4 protein expression associated with the IL28B-T/T variant preactivates the Janus kinase-Stat signaling, leading to impaired HCV clearance by both IFN-α and IFN-λ.


Asunto(s)
Hepatitis C Crónica/tratamiento farmacológico , Interleucinas/genética , Polimorfismo de Nucleótido Simple/genética , Antivirales/farmacología , Genotipo , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/virología , Hepatocitos/metabolismo , Humanos , Interferón-alfa/metabolismo , Interferón-alfa/farmacología , Interferones , Neoplasias Hepáticas/metabolismo
10.
PLoS One ; 10(12): e0141655, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26657215

RESUMEN

BACKGROUND: HCV replication in persistently infected cell culture remains resistant to IFN-α/RBV combination treatment, whereas IFN-λ1 induces viral clearance. The antiviral mechanisms by which IFN-λ1 induces sustained HCV clearance have not been determined. AIM: To investigate the mechanisms by which IFN-λ clears HCV replication in an HCV cell culture model. METHODS: IFN-α sensitive (S3-GFP) and resistant (R4-GFP) cells were treated with equivalent concentrations of either IFN-α or IFN-λ. The relative antiviral effects of IFN-α and IFN-λ1 were compared by measuring the HCV replication, quantification of HCV-GFP expression by flow cytometry, and viral RNA levels by real time RT-PCR. Activation of Jak-Stat signaling, interferon stimulated gene (ISG) expression, and miRNA-122 transcription in S3-GFP and R4-GFP cells were examined. RESULTS: We have shown that IFN-λ1 induces HCV clearance in IFN-α resistant and sensitive replicon cell lines in a dose dependent manner through Jak-Stat signaling, and induces STAT 1 and STAT 2 activation, ISRE-luciferase promoter activation and ISG expression. Stat 3 activation is also involved in IFN-λ1 induced antiviral activity in HCV cell culture. IFN-λ1 induced Stat 3 phosphorylation reduces the expression of hepatocyte nuclear factor 4 alpha (HNF4α) through miR-24 in R4-GFP cells. Reduced expression of HNF4α is associated with decreased expression of miR-122 resulting in an anti-HCV effect. Northern blot analysis confirms that IFN-λ1 reduces miR-122 levels in R4-GFP cells. Our results indicate that IFN-λ1 activates the Stat 3-HNF4α feedback inflammatory loop to inhibit miR-122 transcription in HCV cell culture. CONCLUSIONS: In addition to the classical Jak-Stat antiviral signaling pathway, IFN-λ1 inhibits HCV replication through the suppression of miRNA-122 transcription via an inflammatory Stat 3-HNF4α feedback loop. Inflammatory feedback circuits activated by IFNs during chronic inflammation expose non-responders to the risk of hepatocellular carcinoma.


Asunto(s)
Antivirales/farmacología , Hepacivirus/efectos de los fármacos , Factor Nuclear 4 del Hepatocito/genética , Interleucinas/farmacología , MicroARNs/antagonistas & inhibidores , ARN Viral/antagonistas & inhibidores , Factor de Transcripción STAT3/genética , Línea Celular Tumoral , Retroalimentación Fisiológica , Regulación de la Expresión Génica , Hepacivirus/genética , Hepacivirus/metabolismo , Factor Nuclear 4 del Hepatocito/metabolismo , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hepatocitos/virología , Interacciones Huésped-Patógeno , Humanos , Interferón-alfa/farmacología , Interferones , Janus Quinasa 1/genética , Janus Quinasa 1/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Fosforilación , ARN Viral/biosíntesis , Ribavirina/farmacología , Factor de Transcripción STAT2/genética , Factor de Transcripción STAT2/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Replicación Viral/efectos de los fármacos
11.
Therap Adv Gastroenterol ; 8(5): 263-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26327916

RESUMEN

OBJECTIVES: Although effective, direct acting antiviral (DAA) therapies for genotype 1 (GT 1) hepatitis C virus (HCV) have been associated with compliance challenges. Additionally, treatment at predominantly community-based centers has been associated with low retention of patients on treatment and higher dropout rates. The OPTIMAL Phase IV interventional trial (ClinicalTrials.gov Identifier: NCT01405027) was designed to evaluate the impact of an education program for community investigator (CI) sites participating in a Chronic Liver Disease Foundation study treating chronic GT 1 HCV patients. METHODS: This physician educational program was administered by 22 Hepatology Centers of Educational Expertise (HCEE) academic sites to 33 CI sites asked to participate from December 2011 to July 2012. The HCEE mentors from DAA-experienced academic sites educated those at CI sites on therapeutic management, practice, and patient outcomes through a series of four standardized educational sequence visits regarding the use of first generation HCV protease inhibitors and the overall treatment of HCV. RESULTS: Treatment duration compliance rates for patients treated at CI sites versus those treated at HCEE academic sites were evaluable in 77 of 84 HCEE academic site patients, 102 of 113 patients treated at CI sites, and 179 of 197 overall patients. The treatment duration compliance rates for patients treated at HCEE academic sites, CI sites and overall were 85.4 ± 25.39%, 83.8 ± 27.37%, and 84.5 ± 26.48%, respectively, and did not differ statistically between the groups (p = 0.49). Almost half (47%) of the patients in the study achieved a sustained virological response for 24 weeks (SVR24) regardless of the type of site (p = 0.64). Safety profiles were similar at both HCEE and CI sites. CONCLUSIONS: These results demonstrated that education of CI sites unfamiliar with DAAs resulted in patient outcomes consistent with those observed at DAA-experienced academic sites.

12.
Clin Liver Dis ; 19(3): 529-37, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26195206

RESUMEN

Hepatic encephalopathy (HE) is a commonly encountered sequela of chronic liver disease and cirrhosis with significant associated morbidity and mortality. Although ammonia is implicated in the pathogenesis of HE, the exact underlying mechanisms still remain poorly understood. Its role in the urea cycle, astrocyte swelling, and glutamine and gamma-amino-n-butyric acid systems suggests that the pathogenesis is multifaceted. Greater understanding in its underlying mechanism may offer more targeted therapeutic options in the future, and thus further research is necessary to fully understand the pathogenesis of HE.


Asunto(s)
Amoníaco/sangre , Astrocitos/metabolismo , Encefalopatía Hepática/etiología , Encefalopatía Hepática/metabolismo , Animales , Astrocitos/patología , Barrera Hematoencefálica , Enfermedad Crónica , Glutamina/metabolismo , Encefalopatía Hepática/clasificación , Humanos , Hepatopatías/complicaciones , Ácido gamma-Aminobutírico/metabolismo
13.
Clin Transl Gastroenterol ; 6: e91, 2015 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-26087059

RESUMEN

There is a fine balance in the mutual relationship between the intestinal microbiota and its mammalian host. It is thought that disruptions in this fine balance contribute/account for the pathogenesis of many diseases. Recently, the significance of the relationship between gut microbiota and its mammalian host in the pathogenesis of obesity and the metabolic syndrome has been demonstrated. Emerging data has linked intestinal dysbiosis to several gastrointestinal diseases including inflammatory bowel disease, irritable bowel syndrome, nonalcoholic fatty liver disease, and gastrointestinal malignancy. This article is intended to review the role of gut microbiota maintenance/alterations of gut microbiota as a significant factor as a significant factor discriminating between health and common diseases. Based on current available data, the role of microbial manipulation in disease management remains to be further defined and a focus for further clinical investigation.

14.
PLoS One ; 10(5): e0125962, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25961570

RESUMEN

BACKGROUND: Hepatic steatosis is a risk factor for both liver disease progression and an impaired response to interferon alpha (IFN-α)-based combination therapy in chronic hepatitis C virus (HCV) infection. Previously, we reported that free fatty acid (FFA)-treated HCV cell culture induces hepatocellular steatosis and impairs the expression of interferon alpha receptor-1 (IFNAR1), which is why the antiviral activity of IFN-α against HCV is impaired. AIM: To investigate the molecular mechanism by which IFNAR1 expression is impaired in HCV cell culture with or without free fatty acid-treatment. METHOD: HCV-infected Huh 7.5 cells were cultured with or without a mixture of saturated (palmitate) and unsaturated (oleate) long-chain free fatty acids (FFA). Intracytoplasmic fat accumulation in HCV-infected culture was visualized by oil red staining. Clearance of HCV in FFA cell culture treated with type I IFN (IFN-α) and Type III IFN (IFN-λ) was determined by Renilla luciferase activity, and the expression of HCV core was determined by immunostaining. Activation of Jak-Stat signaling in the FFA-treated HCV culture by IFN-α alone and IFN-λ alone was examined by Western blot analysis and confocal microscopy. Lysosomal degradation of IFNAR1 by chaperone-mediated autophagy (CMA) in the FFA-treated HCV cell culture model was investigated. RESULTS: FFA treatment induced dose-dependent hepatocellular steatosis and lipid droplet accumulation in HCV-infected Huh-7.5 cells. FFA treatment of infected culture increased HCV replication in a concentration-dependent manner. Intracellular lipid accumulation led to reduced Stat phosphorylation and nuclear translocation, causing an impaired IFN-α antiviral response and HCV clearance. Type III IFN (IFN-λ), which binds to a separate receptor, induces Stat phosphorylation, and nuclear translocation as well as antiviral clearance in FFA-treated HCV cell culture. We show here that the HCV-induced autophagy response is increased in FFA-treated cell culture. Pharmacological inhibitors of lysosomal degradation, such as ammonium chloride and bafilomycin, prevented IFNAR1 degradation in FFA-treated HCV cell culture. Activators of chaperone-mediated autophagy, including 6-aminonicotinamide and nutrient starvation, decreased IFNAR1 levels in Huh-7.5 cells. Co-immunoprecipitation, colocalization and siRNA knockdown experiments revealed that IFNAR1 but not IFNLR1 interacts with HSC70 and LAMP2A, which are core components of chaperone-mediated autophagy (CMA). CONCLUSION: Our study presents evidence indicating that chaperone-mediated autophagy targets IFNAR1 degradation in the lysosome in FFA-treated HCV cell culture. These results provide a mechanism for why HCV induced autophagy response selectively degrades type I but not the type III IFNAR1.


Asunto(s)
Autofagia/efectos de los fármacos , Ácidos Grasos no Esterificados/metabolismo , Lisosomas/metabolismo , Receptor de Interferón alfa y beta/metabolismo , Antivirales/farmacología , Línea Celular , Células Cultivadas , Ácidos Grasos no Esterificados/farmacología , Hígado Graso/genética , Hígado Graso/metabolismo , Hígado Graso/virología , Expresión Génica , Hepacivirus/efectos de los fármacos , Hepacivirus/fisiología , Humanos , Interferón Tipo I/farmacología , Interferón gamma/farmacología , Quinasas Janus/metabolismo , Fosforilación , Unión Proteica , Proteolisis/efectos de los fármacos , Receptor de Interferón alfa y beta/genética , Factores de Transcripción STAT/metabolismo , Transducción de Señal/efectos de los fármacos , Replicación Viral/efectos de los fármacos
15.
World J Hepatol ; 7(3): 498-506, 2015 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-25848473

RESUMEN

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the most common causes of chronic liver diseases and hepatocelluar carcinomas. Over the past few years, the liver-enriched microRNA-122 (miR-122) has been shown to differentially regulate viral replication of HBV and HCV. It is notable that the level of miR-122 is positively and negatively regulated by HCV and HBV, respectively. Consistent with the well-documented phenomenon that miR-122 promotes HCV accumulation, inhibition of miR-122 has been shown as an effective therapy for the treatment of HCV infection in both chimpanzees and humans. On the other hand, miR-122 is also known to block HBV replication, and HBV has recently been shown to inhibit miR-122 expression; such a reciprocal inhibition between miR-122 and HBV suggests an intriguing possibility that miR-122 replacement may represent a potential therapy for treatment of HBV infection. As HBV and HCV have shared transmission routes, dual infection is not an uncommon scenario, which is associated with more advanced liver disease than either HBV or HCV mono-infection. Thus, there is a clear need to further understand the interaction between HBV and HCV and to delineate the role of miR-122 in HBV/HCV dual infection in order to devise effective therapy. This review summarizes the current understanding of HBV/HCV dual infection, focusing on the pathobiological role and therapeutic potential of miR-122.

17.
Clin Immunol ; 157(2): 103-13, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25638412

RESUMEN

IL-18 is induced in food allergy and EoE is food allergen-induced disease. Therefore, we tested the hypothesis whether IL-18 is involved in food allergen-induced EoE pathogenesis. Accordingly, we examined normal SPT+ and SPT- EoE patient blood and biopsy samples for IL-18, IL-18Rα, ICAM and VCAM expression. Herein, we show increased IL-18 level is highly significant in food allergen SPT+ compared to SPT- EoE patients. We also report that IL-18Rα+ cells and mRNA levels are induced in the esophageal biopsies of EoE patients and blood IL-18 levels correlate with esophageal eosinophilia (P<0.01). Additionally, we report that the levels of esophageal eosinophil and mast cells correlate with ICAM expression in human EoE. Mechanistically, we show that IL-18 in vitro stimulates iNKT cells and endothelial cells and induce eosinophil active cytokines IL-5 and IL-13. We provide the evidence that IL-18 is critical cytokine involved in activation of iNKT cells and ICAM in promoting human EoE.


Asunto(s)
Esofagitis Eosinofílica/inmunología , Esófago/inmunología , Hipersensibilidad a los Alimentos/inmunología , Molécula 1 de Adhesión Intercelular/genética , Subunidad alfa del Receptor de Interleucina-18/inmunología , Interleucina-18/inmunología , Células T Asesinas Naturales/inmunología , ARN Mensajero/metabolismo , Molécula 1 de Adhesión Celular Vascular/genética , Adolescente , Estudios de Casos y Controles , Línea Celular , Niño , Preescolar , Esofagitis Eosinofílica/etiología , Esofagitis Eosinofílica/genética , Esófago/metabolismo , Esófago/patología , Femenino , Hipersensibilidad a los Alimentos/complicaciones , Hipersensibilidad a los Alimentos/genética , Humanos , Lactante , Molécula 1 de Adhesión Intercelular/metabolismo , Interleucina-13/genética , Interleucina-13/inmunología , Interleucina-13/metabolismo , Subunidad alfa del Receptor de Interleucina-18/genética , Subunidad alfa del Receptor de Interleucina-18/metabolismo , Interleucina-5/genética , Interleucina-5/inmunología , Interleucina-5/metabolismo , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa , Pruebas Cutáneas , Molécula 1 de Adhesión Celular Vascular/metabolismo
18.
J Virol ; 89(1): 626-42, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25339775

RESUMEN

UNLABELLED: Ribavirin (RBV) continues to be an important component of interferon-free hepatitis C treatment regimens, as RBV alone does not inhibit hepatitis C virus (HCV) replication effectively; the reason for this ineffectiveness has not been established. In this study, we investigated the RBV resistance mechanism using a persistently HCV-infected cell culture system. The antiviral activity of RBV against HCV was progressively impaired in the persistently infected culture, whereas interferon lambda 1 (IFN-λ1), a type III IFN, showed a strong antiviral response and induced viral clearance. We found that HCV replication in persistently infected cultures induces an autophagy response that impairs RBV uptake by preventing the expression of equilibrative nucleoside transporter 1 (ENT1). The Huh-7.5 cell line treated with an autophagy inducer, Torin 1, downregulated membrane expression of ENT1 and terminated RBV uptake. In contrast, the autophagy inhibitors hydroxychloroquine (HCQ), 3-methyladenine (3-MA), and bafilomycin A1 (BafA1) prevented ENT1 degradation and enhanced RBV antiviral activity. The HCV-induced autophagy response, as well as treatment with Torin 1, degrades clathrin heavy chain expression in a hepatoma cell line. Reduced expression of the clathrin heavy chain by HCV prevents ENT1 recycling to the plasma membrane and forces ENT1 to the lysosome for degradation. This study provides a potential mechanism for the impairment of RBV antiviral activity in persistently HCV-infected cell cultures and suggests that inhibition of the HCV-induced autophagy response could be used as a strategy for improving RBV antiviral activity against HCV infection. IMPORTANCE: The results from this work will allow a review of the competing theories of antiviral therapy development in the field of HCV virology. Ribavirin (RBV) remains an important component of interferon-free hepatitis C treatment regimens. The reason why RBV alone does not inhibit HCV replication effectively has not been established. This study provides a potential mechanism for why RBV antiviral activity is impaired in persistently HCV-infected cell cultures and suggests that inhibition of the HCV-induced autophagy response could be used as a strategy to increase RBV antiviral activity against HCV infection. Therefore, it is anticipated that this work would generate a great deal of interest, not only among virologists but also among the general public.


Asunto(s)
Antivirales/metabolismo , Clatrina/metabolismo , Resistencia a Medicamentos , Tranportador Equilibrativo 1 de Nucleósido/metabolismo , Hepacivirus/efectos de los fármacos , Ribavirina/metabolismo , Línea Celular , Hepatocitos/metabolismo , Hepatocitos/virología , Humanos , Transporte de Proteínas
19.
Lancet ; 385(9973): 1075-86, 2015 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-25467591

RESUMEN

BACKGROUND: There is a high medical need for an interferon-free, all-oral, short-duration therapy for hepatitis C virus (HCV) that is highly effective across diverse patient populations, including patients with cirrhosis or previous null response to pegylated interferon (peginterferon) plus ribavirin (PR-null responders). We aimed to assess the efficacy, safety, and effective treatment duration of grazoprevir (an HCV NS3/4A protease inhibitor) combined with elbasvir (an HCV NS5A inhibitor) with or without ribavirin in patients with HCV genotype 1 infection with baseline characteristics of poor response. METHODS: The C-WORTHY trial is a randomised, open-label phase 2 trial of grazoprevir plus elbasvir with or without ribavirin; here we report findings for two cohorts of previously untreated patients with cirrhosis (cohort 1) and those with previous PR-null response with or without cirrhosis (cohort 2) enrolled in part B of the study. Eligible patients were adults aged 18 years or older with chronic HCV genotype 1 infection and HCV RNA concentrations of 10 000 IU/mL or higher in peripheral blood. We randomly assigned patients to receive grazoprevir (100 mg daily) and elbasvir (50 mg daily) with or without ribavirin for 12 or 18 weeks. Randomisation was done centrally with an interactive voice response system; patients and study investigators were masked to treatment duration up to week 12 but not to treatment allocation. The primary endpoint was the proportion of patients achieving HCV RNA less than 25 IU/mL at 12 weeks after end of treatment (SVR12), assessed by COBAS TaqMan version 2.0. This study is registered with ClinicalTrials.gov, number NCT01717326. FINDINGS: We describe findings for 253 patients enrolled in cohort 1 (n=123) or cohort 2 (n=130). In cohort 1, we randomly assigned 60 patients to the 12-week regimen (31 with ribavirin and 29 with no ribavirin) and 63 to the 18-week regimen (32 with ribavirin and 31 with no ribavirin); in cohort 2, we randomly assigned 65 patients to the 12-week regimen (32 with ribavirin and 33 with no ribavirin) and 65 to the 18-week regimen (33 with ribavirin and 32 with no ribavirin. High SVR12 rates were achieved irrespective of the use of ribavirin or extension of the treatment duration from 12 to 18 weeks; SVR12 rates ranged from 90% (95% CI 74-98; 28/31; cohort 1, 12 weeks, ribavirin-containing) to 100% (95% CI 89-100; 33/33; cohort 2, 18 weeks, ribavirin-containing). Among patients treated for 12 weeks with grazoprevir plus elbasvir without ribavirin, 97% (95% CI 82-100, 28/29) of patients in cohort 1 and 91% (76-98, 30/33) of patients in cohort 2 achieved SVR12. Adverse events reported in more than 10% of patients were fatigue (66 patients, 26% [95% CI 21-32]), headache (58 patients, 23% [95% CI 18-29]), and asthenia (35 patients, 14% [95% CI 10-19]). INTERPRETATION: Treatment with grazoprevir plus elbasvir, both with and without ribavirin and for both 12 and 18 weeks' treatment duration, showed high rates of efficacy in previously untreated patients with cirrhosis and previous PR-null responders with and without cirrhosis. These results support the phase 3 development of grazoprevir plus elbasvir. FUNDING: Merck & Co, Inc.


Asunto(s)
Antivirales/administración & dosificación , Benzofuranos/administración & dosificación , Hepatitis C Crónica/tratamiento farmacológico , Imidazoles/administración & dosificación , Cirrosis Hepática/etiología , Quinoxalinas/administración & dosificación , ARN Viral/sangre , Ribavirina/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Amidas , Carbamatos , Ciclopropanos , Esquema de Medicación , Quimioterapia Combinada , Femenino , Hepacivirus/genética , Hepatitis C Crónica/complicaciones , Humanos , Interferones/uso terapéutico , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Sulfonamidas , Insuficiencia del Tratamiento , Resultado del Tratamiento , Carga Viral , Adulto Joven
20.
PLoS One ; 9(9): e108616, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25265476

RESUMEN

PURPOSE: Chronic Hepatitis C Virus (HCV)-infected patients with liver cirrhosis (LC) respond poorly to interferon-alpha (IFN-α) and ribavirin (RBV) combination therapy, but the reason for this is unclear. We previously reported that HCV-infection induces endoplasmic reticulum (ER) stress and autophagy response that selectively down regulates the type I IFN-α receptor-1 (IFNAR1) and RBV transporters (CNT1 and ENT1), leading to IFN-α/RBV resistance. The goal of this study is to verify whether an increase in ER stress and autophagy response is also associated with the reduced expression of IFNAR1 and RBV transporters in chronic HCV-infected patients. METHODS: Primary human hepatocytes (PHH) were infected with cell culture grown HCV particles (JFH-ΔV3-Rluc). HCV replication was confirmed by the detection of viral RNA by RT-qPCR and HCV-core protein by Western blotting. The ER stress and autophagy response and expression of IFN receptors and RBV transporters in HCV infected PHH and liver tissues derived from patients were measured by Western blotting. RESULT: HCV infection of PHH showed impaired expression of IFNAR1, IFNγR1 (Type II IFN receptor) and RBV transporters but not IL10Rß (Type III IFN-λ receptor). ER stress markers (BiP, IRE1α and peIF2α) and autophagy response (LC3II, Beclin 1 and ATG5) were induced in HCV infected chronic liver disease (CLD) and LC patients. Liver biopsies (CLD) show a 50% reduced expression of IFNAR1 and RBV transporters. Furthermore, the expression of IFNAR1 and RBV transporters was impaired in almost all LC patients. CONCLUSION: HCV infection induces ER stress and autophagy response in infected PHH and chronically infected liver tissues. The expression of IFNAR1, IFNγR1 and RBV transporters were significantly impaired in CLD and cirrhotic livers. Our study provides a potential explanation for the reduced response rate of IFN-α and RBV combination therapy in HCV infected patients with liver cirrhosis.


Asunto(s)
Hepacivirus/fisiología , Hepatitis C Crónica/metabolismo , Hepatitis C Crónica/virología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/virología , Receptor de Interferón alfa y beta/metabolismo , Receptores de Interferón/metabolismo , Autofagia , Transporte Biológico , Biopsia , Células Cultivadas , Regulación hacia Abajo , Estrés del Retículo Endoplásmico , Etanol/farmacología , Ácidos Grasos no Esterificados/farmacología , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/patología , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Hepatocitos/virología , Humanos , Hígado/patología , Hígado/virología , Cirrosis Hepática/patología , Ribavirina , Replicación Viral
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