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1.
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
2.
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
3.
Scand J Gastroenterol ; 46(1): 91-7, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20809771

RESUMEN

OBJECTIVE: The novel adipokines omentin, chemerin, and adipsin are associated with insulin resistance and the components of the metabolic syndrome. We assayed circulating levels of these molecules and examined their association with clinical, biochemical, and histological phenotypes in patients with nonalcoholic fatty liver disease (NAFLD). MATERIAL AND METHODS: Serum levels of omentin, chemerin, and adipsin were assayed by enzyme-linked immunosorbent assay in 99 patients with biopsy-proven NAFLD and 75 control subjects. We analyzed associations between adipokines and the characteristics of patients with NAFLD using multivariable linear regression models. RESULTS: Adipsin levels did not differ between patients and controls, whereas both omentin and chemerin levels were significantly higher in patients with biopsy-proven NAFLD than in controls (both p values <0.001). Serum omentin levels were significantly associated with C-reactive protein (r = 0.29, p < 0.01) and the degree of hepatocyte ballooning (r = 0.27, p < 0.01), whereas chemerin showed a modest association with liver fibrosis (r = 0.22, p = 0.04). After stepwise linear regression analysis adjusting for potential confounders, serum omentin levels retained their independent significance as a predictor of hepatocyte ballooning in patients with NAFLD (ß = 1.42; t = 2.79, p < 0.01). CONCLUSIONS: Our results suggest that serum omentin levels are raised in patients with NAFLD regardless of potential confounders and represent an independent predictor of hepatocyte ballooning.


Asunto(s)
Quimiocinas/sangre , Factor D del Complemento/análisis , Citocinas/sangre , Hígado Graso/sangre , Hígado Graso/patología , Lectinas/sangre , Biopsia , Estudios de Casos y Controles , Femenino , Proteínas Ligadas a GPI/sangre , Humanos , Péptidos y Proteínas de Señalización Intercelular , Masculino , Persona de Mediana Edad
4.
Clin Chem Lab Med ; 49(1): 93-7, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21077793

RESUMEN

BACKGROUND: Evidence suggests that zinc-α(2)-glycoprotein (ZAG) might serve as a biomarker for human metabolic alterations. We measured serum ZAG in patients with non-alcoholic fatty liver disease (NAFLD), a hepatic manifestation of the metabolic syndrome, and examined its association with clinical, biochemical, and histological phenotypes. METHODS: Serum ZAG was determined using ELISA in 90 patients with biopsy-proven NAFLD and 81 controls. RESULTS: Serum ZAG concentrations did not differ in patients with NAFLD (median 61 µg/mL; interquartile range: 56-73 µg/mL) compared with healthy controls (median 66 µg/mL; interquartile range: 56-78 µg/mL, Mann-Whitney U-test, p=NS). However, among patients with NAFLD serum ZAG concentrations were significantly higher in males and in those with the metabolic syndrome. After stepwise linear regression analysis, serum ZAG concentrations were the only independent predictor of the number of metabolic syndrome components in patients with NAFLD (ß=0.22; t=2.001, p<0.05). CONCLUSIONS: In summary, the hypothesis of an association between NAFLD and serum ZAG concentrations is not supported by the present results. However, ZAG remains an interesting molecule for further research in the field of human metabolic disorders.


Asunto(s)
Proteínas de Plasma Seminal/sangre , Biomarcadores/sangre , Biomarcadores/metabolismo , Estudios de Casos y Controles , Hígado Graso/sangre , Hígado Graso/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico , Zn-alfa-2-Glicoproteína
5.
Scand J Clin Lab Invest ; 71(8): 631-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21859358

RESUMEN

Our aim was to examine the relation of serum osteocalcin (OCN) levels with the clinical, biochemical, and histological characteristics of patients with biopsy-proven nonalcoholic fatty liver disease (NAFLD). We carried out a case-control study including 99 patients with biopsy-proven NAFLD and 75 age- and sex-matched controls. Concentrations of OCN were measured in aprotinin-treated serum samples using a solid-phase enzyme amplified sensitivity immunoassay. Serum OCN levels were significantly lower in patients with NAFLD than in healthy controls. In patients with NAFLD, serum OCN levels were inversely associated with ALT (r = -0.36, p < 0.001), AST (r =-0.39, p < 0.001), HOMA-IR (r = -0.30, p < 0.01) and the degree of hepatocyte ballooning (r =-0.20, p < 0.05). Serum OCN was the only independent predictor of the degree of hepatocyte ballooning in NAFLD patients (ß = -0.24; t = -2.146, p < 0.05). Compared with controls, NAFLD patients have a decrease in serum OCN concentrations, which is significantly associated with serum transaminases and the extent of hepatocyte ballooning.


Asunto(s)
Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Hígado Graso/sangre , Hígado Graso/enzimología , Hepatocitos/enzimología , Hígado/enzimología , Osteocalcina/sangre , Adulto , Aprotinina/metabolismo , Biomarcadores/sangre , Biopsia , Estudios de Casos y Controles , Hígado Graso/patología , Femenino , Hepatocitos/patología , Histocitoquímica , Humanos , Inmunoensayo , Hígado/patología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico , Turquía
6.
South Med J ; 104(8): 579-83, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21886067

RESUMEN

OBJECTIVES: First-line standard eradication efficacy with lansoprazole, amoxicillin and clarithromycin regressed over 10 years. The aim of this study was to evaluate the efficacy and tolerability of a levofloxacin-based regimen in patients with peptic ulcer after failure of the standard first-line H.pylori eradication therapy in a country with a high rate of infection. METHODS: A total of 91 peptic ulcer patients who were diagnosed H.pylori positive proven by rapid urease test and histology between November 2005 to March 2008 were given lansoprazole 30 mg bid, amoxicillin 1 g bid and clarithromycin 500 mg bid (LAC) for 14 days. After three months from the first line eradication treatment omeprazole 20 mg bid, levofloxacin 500 mg bid, amoxicillin 1 g bid (OLA) 7 day treatment regimen was recommended as a second-line therapy for 37 patients who failed at first-line standard triple therapy. RESULTS: Eradication rates for LAC regimen were found to be 57.14% (52/91) for intention to treat and 58.42% (52/89) for per protocol analysis. Eradication rates for OLA regimen were found to be 37.83% (14/37) for ITT and 41.17% (14/34) for PP analysis. CONCLUSION: OLA regimen eradication rate was successful only in 40% of patients who failed in the first-line eradication. New eradication treatment strategies must be performed, at least in Turkey.


Asunto(s)
Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Levofloxacino , Ofloxacino/uso terapéutico , Omeprazol/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Amoxicilina/efectos adversos , Antiulcerosos/uso terapéutico , Quimioterapia Combinada , Femenino , Infecciones por Helicobacter/microbiología , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Ofloxacino/efectos adversos , Omeprazol/efectos adversos , Úlcera Péptica/tratamiento farmacológico , Úlcera Péptica/microbiología , Resultado del Tratamiento , Adulto Joven
7.
Eur J Clin Invest ; 40(10): 887-92, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20624171

RESUMEN

BACKGROUND: The fibroblast growth factor 21 (FGF21) hormonal pathway is a metabolic signalling cascade and has been recently identified as the master hormonal regulator of glucose, lipids and overall energy balance. In this observational, case-control study, we assayed serum levels of FGF21 in patients with nonalcoholic fatty liver disease (NAFLD), a hepatic manifestation of the metabolic syndrome, and examined their association with clinical, biochemical and histological phenotypes. MATERIALS AND METHODS: Serum levels of FGF21 were assayed by ELISA in 82 patients with biopsy-proven NAFLD and 77 controls. We analysed associations between FGF21 and the characteristics of patients with NAFLD by multiple linear regression analysis. RESULTS: Levels of FGF21 were significantly higher in patients with NAFLD (median 200 pg mL(-1) ; interquartile range: 87-410 pg mL(-1)) than in healthy controls (median 93 pg mL(-1) ; interquartile range: 70-180 pg mL(-1) , Mann-Whitney U-test, P<0·001). There was a stepwise increase in serum FGF21 levels according to the liver steatosis score (median level in subjects with score 1: 170 pg mL(-1) ; score 2: 220 pg mL(-1) ; score 3: 280 pg mL(-1) , P for trend <0·01). After stepwise linear regression analysis, serum FGF21 levels were the only independent predictor of hepatic steatosis scores in patients with NAFLD (ß=0·26; t=2·659, P<0·01). CONCLUSIONS: Serum FGF21 levels are increased in patients with NAFLD regardless of potential confounders and represent an independent predictor of liver steatosis. These findings support further investigation of this molecule in metabolic liver diseases.


Asunto(s)
Hígado Graso/sangre , Factores de Crecimiento de Fibroblastos/metabolismo , Adulto , Anciano , Estudios de Casos y Controles , Hígado Graso/metabolismo , Hígado Graso/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico , Adulto Joven
8.
Scand J Clin Lab Invest ; 70(8): 541-6, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20942739

RESUMEN

OBJECTIVE: Osteoprotegerin (OPG) is a member of the tumor necrosis factor superfamily with pleiotropic effects on inflammation, endocrine function and the immune system. Reduced OPG levels are related to insulin resistance. We tested the hypothesis that serum levels of OPG may be associated with nonalcoholic fatty liver disease (NAFLD). MATERIAL AND METHODS: Four groups of patients were enrolled in the present study: subjects with definite nonalcoholic steatohepatitis (NASH, n = 56), borderline NASH (n = 26), simple fatty liver (n = 17) and healthy controls without evidence of liver disease (n = 58). Serum levels of OPG were measured by ELISA. RESULTS: Concentrations of OPG were significantly lower in patients with definite NASH (median: 45 pg/mL, p < 0.001) and borderline NASH (57 pg/mL, p < 0.001) than in controls (92 pg/mL). The area under the ROC curve for distinguishing between steatohepatitis (definite NASH plus borderline NASH) and healthy controls using OPG was 0.82. The use of a cut-off level < 74 pg/mL for serum OPG levels yielded sensitivity and specificity values of 75.6% and 75.9%, respectively. CONCLUSIONS: Serum osteoprotegerin concentrations are reduced in patients with the more severe forms of NAFLD and may serve as a noninvasive biomarker to identify patients with NASH.


Asunto(s)
Hígado Graso/sangre , Osteoprotegerina/sangre , Alcoholes , Estudios de Casos y Controles , Diagnóstico Diferencial , Hígado Graso/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC
9.
Diseases ; 8(4)2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33182651

RESUMEN

BACKGROUND AND AIM: Although constitutional and respiratory symptoms such as cough and fever are the most common symptoms in patients infected with COVID-19, gastrointestinal (GI) tract involvement has been observed by endoscopic biopsies. Multiple GI symptoms, including diarrhea, nausea or vomiting and abdominal pain, have also been reported. This review aims to present the currently available data regarding the GI symptoms of COVID-19 patients, and to compare the frequency of GI symptoms in early stage (Eastern) mostly Chinese data to the current stage (Western) non-Chinese data. METHODS: We performed a systematic literature search to identify both published studies by using PubMed, Google Scholar, and CNKI (Chinese medical search engine), and yet unpublished studies through medRxiv and bioRxiv. We also reviewed the cross references of the detected articles. We conducted a Medical Subject Headings (MeSH) search up until 20 September 2020. We pooled the prevalence of symptoms of diarrhea, anorexia, nausea, vomiting, and abdominal pain by using the Freeman-Tukey's transforming random effect model. RESULTS: A total of 118 studies were included in the systematic review and 44 of them were included in the meta-analysis. There was a significant heterogeneity between the studies; therefore, the random effects model was used. The pooled prevalence estimate of any GI symptoms reported was found to be 0.21 (95%CI, 0.16-0.27). Anorexia was the most commonly reported GI symptom at 18% (95%CI, 0.10-0.27) followed by diarrhea at 15% (95%CI, 0.12-0.19). Diarrhea, abdominal pain, nausea/vomiting, and respiratory symptoms were more common in non-Chinese studies. The prevalence of abdominal pain was lower in the "inpatient-only" studies when compared with studies that included outpatients only and those including both inpatients and outpatients. CONCLUSIONS: In this comprehensive systematic review and meta-analysis study, we observed higher rates of diarrhea, nausea/vomiting, and abdominal pain in COVID-19 infected patients among non-Chinese studies compared to Chinese studies. We also observed a higher prevalence of GI symptoms in Chinese studies than was reported previously. Non-respiratory symptoms, including GI tract symptoms, should be more thoroughly and carefully evaluated and reported in future studies.

10.
Cancers (Basel) ; 11(10)2019 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-31547152

RESUMEN

Hepatitis C virus (HCV) infection compromises the natural defense mechanisms of the liver leading to a progressive end stage disease such as cirrhosis and hepatocellular carcinoma (HCC). The hepatic stress response generated due to viral replication in the endoplasmic reticulum (ER) undergoes a stepwise transition from adaptive to pro-survival signaling to improve host cell survival and liver disease progression. The minute details of hepatic pro-survival unfolded protein response (UPR) signaling that contribute to HCC development in cirrhosis are unknown. This study shows that the UPR sensor, the protein kinase RNA-like ER kinase (PERK), mediates the pro-survival signaling through nuclear factor erythroid 2-related factor 2 (NRF2)-mediated signal transducer and activator of transcription 3 (STAT3) activation in a persistent HCV infection model of Huh-7.5 liver cells. The NRF2-mediated STAT3 activation in persistently infected HCV cell culture model resulted in the decreased expression of hepatocyte nuclear factor 4 alpha (HNF4A), a major liver-specific transcription factor. The stress-induced inhibition of HNF4A expression resulted in a significant reduction of liver-specific microRNA-122 (miR-122) transcription. It was found that the reversal of hepatic adaptive pro-survival signaling and restoration of miR-122 level was more efficient by interferon (IFN)-based antiviral treatment than direct-acting antivirals (DAAs). To test whether miR-122 levels could be utilized as a biomarker of hepatic adaptive stress response in HCV infection, serum miR-122 level was measured among healthy controls, and chronic HCV patients with or without cirrhosis. Our data show that serum miR-122 expression level remained undetectable in most of the patients with cirrhosis (stage IV fibrosis), suggesting that the pro-survival UPR signaling increases the risk of HCC through STAT3-mediated suppression of miR-122. In conclusion, our data indicate that hepatic pro-survival UPR signaling suppresses the liver-specific HNF4A and its downstream target miR-122 in cirrhosis. These results provide an explanation as to why cirrhosis is a risk factor for the development of HCC in chronic HCV infection.

12.
Clin Appl Thromb Hemost ; 13(4): 439-42, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17911198

RESUMEN

Testicular cancer is the most common solid tumor among young men aged 15 to 35 years. Combination chemotherapy with cisplatin, etoposide, and bleomycin remains the mainstay of treatment. We present a 27-year-old man who presented with an acute anterior myocardial infarction during the second course of chemotherapy for seminoma. Because the patient had no significant risk factors for coronary heart disease, the infarction was likely caused by the chemotherapy regimen.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Infarto del Miocardio/inducido químicamente , Seminoma/tratamiento farmacológico , Neoplasias Testiculares/tratamiento farmacológico , Adulto , Bleomicina/administración & dosificación , Bleomicina/efectos adversos , Coagulación Sanguínea/efectos de los fármacos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Etopósido/administración & dosificación , Etopósido/efectos adversos , Humanos , Masculino , Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Factores de Riesgo
15.
Hormones (Athens) ; 5(1): 67-71, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16728387

RESUMEN

A patient with an intrasellar germinoma leading to pituitary stalk thickening is reported. The patient, a 24-year old woman, presented with hyperprolactinemia, secondary hypothyroidism, and hypogonadotropic hypogonadism with no evidence of diabetes insipidus. Cerebrospinal fluid (CSF) examination revealed an increased number of lymphocytes and histiocytes. Although beta-HCG concentration was normal (<2 mIU/mL) in the CSF, increased beta-HCG concentration was detected in the serum. Systemic glucocorticoid treatment led to a decrease in CSF cell count, but no regression of the sellar mass was noted. A diagnostic biopsy was performed and showed an intrasellar germinoma. The patient underwent conventional radiotherapy. Complete resolution of the mass lesion and normalization of beta-HCG concentration in the serum were observed three months after radiotherapy. The presence of intrasellar mass lesion in association with pituitary stalk thickening may cause difficulties in the differential diagnosis. Histopathological examination is essential in equivocal cases in order to reach accurate diagnosis and apply the most appropriate therapy.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Gonadotropina Coriónica Humana de Subunidad beta/líquido cefalorraquídeo , Germinoma/diagnóstico , Enfermedades de la Hipófisis , Adulto , Biopsia , Neoplasias Encefálicas/líquido cefalorraquídeo , Neoplasias Encefálicas/radioterapia , Recuento de Células , Líquido Cefalorraquídeo/citología , Diagnóstico Diferencial , Femenino , Germinoma/líquido cefalorraquídeo , Germinoma/radioterapia , Glucocorticoides/uso terapéutico , Histiocitos/patología , Humanos , Hiperprolactinemia , Hipogonadismo , Hipotiroidismo , Linfocitos/patología
16.
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
17.
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
18.
Noro Psikiyatr Ars ; 51(2): 103-109, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28360608

RESUMEN

INTRODUCTION: Myocardial infarction (MI) as a life-threatening event, carrying high risk of recurrence and chronic disabling complications, increases the risk of developing acute stress disorder (ASD), posttraumatic stress disorder (PTSD), or both. The aim of this study was to investigate the relationship between illness perceptions and having ASD, PTSD, or both in patients after MI. METHOD: Seventy-six patients diagnosed with acute MI were enrolled into our prospective study. We evaluated patients during the first week and six months after MI. Patients were assessed by using the Clinician Administered PTSD Scale (CAPS), the Hamilton Depression Rating Scale (HDRS), the Hamilton Anxiety Rating Scale (HARS), the Brief Illness Perception Questionnaire (BIPQ), and a semi-structured interview for socio-demographic characteristics during both the first and second evaluations. RESULTS: Acute stress disorder (ASD) developed in 9.2% of patients and PTSD developed in 11.9% of patients with MI. Illness perception factors of 'consequences, identity and concern' predicted the occurrence of both ASD and PTSD, whereas 'emotion' predicted only PTSD. CONCLUSION: The factors of illness perceptions predicted the induction of ASD and PTSD in patients who had acute MI.

19.
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
20.
Tumori ; 99(1): 10-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23548993

RESUMEN

AIMS AND BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) are two major causes of liver disease worldwide. Epidemiological and clinical data have clearly demonstrated that NAFLD and its associated metabolic abnormalities are a risk factor for HCC. Traditionally, the mechanisms whereby NAFLD acts as a risk for HCC are believed to include replicative senescence of steatotic hepatocytes and compensatory hyperplasia of progenitor cells as a reaction to chronic hepatic injury. Recent years have witnessed significant advances in our understanding of the mechanisms underlying the link between NAFLD and HCC. METHODS: In the present review, we provide an update on the pathophysiological pathways linking NAFLD and its associated metabolic derangements to malignant hepatic transformation, with a special focus on insulin resistance, adipokines, inflammation, and angiogenesis. We will also discuss the potential therapeutic implications that such molecular links carry. RESULTS: Although treating NAFLD could reduce the risk of malignant hepatic transformation, no long-term studies focusing on this issue have been conducted thus far. Insulin resistance, inflammation as well as derangements in adipokines and angiogenic factors associated with NAFLD are closely intertwined with the risk of developing HCC. CONCLUSIONS: Traditional therapeutic approaches in NAFLD including metformin and statins may theoretically reduce the risk of HCC by acting on common pathophysiological pathways shared by NAFLD and HCC.


Asunto(s)
Carcinoma Hepatocelular , Transformación Celular Neoplásica/metabolismo , Hígado Graso , Neoplasias Hepáticas , Adipoquinas/metabolismo , Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/fisiopatología , Carcinoma Hepatocelular/prevención & control , Ejercicio Físico , Hígado Graso/complicaciones , Hígado Graso/epidemiología , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/fisiopatología , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Hipoglucemiantes/administración & dosificación , Inflamación/metabolismo , Resistencia a la Insulina , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/fisiopatología , Neoplasias Hepáticas/prevención & control , Metformina/administración & dosificación , Neovascularización Patológica , Enfermedad del Hígado Graso no Alcohólico , Pérdida de Peso
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