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1.
Nutrition ; 22(2): 114-22, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16459223

RESUMO

OBJECTIVE: We investigated the effects of vitamin E and C supplementation on the fatty acid composition of mononuclear cells and on the clinical observations in patients who had chronic hepatitis C and received interferon-alpha-2b (IFN-alpha-2b) and ribavirin combination therapy. METHODS: Patients were randomly allocated to receive daily 500 mg of vitamin E and 750 mg of vitamin C (vitamin group, n = 14) or no supplement (non-vitamin group, n = 16) in addition to IFN-alpha-2b and ribavirin therapy. The fatty acid composition of mononuclear cell phospholipids was analyzed before and at 2, 4, and 8 wk after treatment. RESULTS: After vitamin supplementation, plasma and red blood cell alpha-tocopherol and plasma ascorbic acid levels increased in the vitamin group. Serum levels of alanine aminotransferase decreased significantly after 2 wk of treatment in both groups. At the start of treatment, a lower level of eicosapentaenoic acid (EPA) and a higher level of the molar ratio of arachidonic acid to EPA in mononuclear cells were observed in the present patients compared with healthy volunteers, and a significant correlation between the molar ratio and serum alanine aminotransferase level was found. The EPA level of mononuclear cells was maintained in the vitamin group during treatment, whereas a significant decrease was observed in the non-vitamin group at 4 and 8 wk after treatment. CONCLUSIONS: Antioxidant vitamin supplementation during IFN-alpha-2b and ribavirin therapy prevented a decrease in EPA of mononuclear cell phospholipids. If a further decrease in the ratio of arachidonic acid to EPA can be achieved by using oral EPA supplementation, the efficacy of IFN-alpha-2b and ribavirin therapy may be improved.


Assuntos
Antivirais/uso terapêutico , Ácido Ascórbico/uso terapêutico , Ácidos Graxos Insaturados/metabolismo , Hepatite C Crônica/tratamento farmacológico , Leucócitos Mononucleares/química , Vitamina E/uso terapêutico , Vitaminas/uso terapêutico , Alanina Transaminase/metabolismo , Ácido Ascórbico/sangue , Suplementos Nutricionais , Sinergismo Farmacológico , Quimioterapia Combinada , Ácido Eicosapentaenoico , Ácidos Graxos Insaturados/análise , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Ribavirina/uso terapêutico , Resultado do Tratamento , Carga Viral , Vitamina E/sangue
2.
J Gastroenterol ; 40(6): 617-24, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16007396

RESUMO

BACKGROUND: Oxidative stress contributes to the pathogenesis of chronic hepatitis C. The aim of this study was to assess the peroxidation of n-3 polyunsaturated fatty acids (PUFAs) in the liver and its relation to hepatic steatosis in chronic hepatitis C. METHODS: We immunohistochemically detected malondialdehyde (MDA)-, 4-hydroxy-2-nonenal (HNE)-, and 4-hydroxy-2-hexenal (HHE)-protein adducts in liver biopsy specimens from 55 patients with chronic hepatitis C. Cells stained positively for HHE-protein adducts were quantified using computer-based image analysis. Fatty-acid composition was determined, by gas chromatography, for the noncancerous portions of resected livers, with or without steatosis, obtained from two patients with hepatitis C virus-associated hepatocellular carcinoma. RESULTS: The detection rate of HHE-protein adducts (63.6%) was significantly higher than that of MDA-protein adducts (21.8%; P < 0.001) or HNE-protein adducts (29.1%; P < 0.001). Areas positively stained for HHE-protein adducts (HHE-positive areas) were significantly larger in 18 patients with steatosis (6.2 +/- 3.6%) than in 17 patients without steatosis (3.4 +/- 2.6%; P = 0.01). Resected liver tissue with steatosis showed a larger HHE-positive area (18.6%) and higher ratio of n-6 PUFA content to n-3 PUFA content (3 : 1) than liver tissue without steatosis (7.2%; 2 : 3). On multivariate analysis, the HHE-positive area (odds ratio, 1.55; 95% confidence interval [CI], 1.08-2.23; P = 0.019) was a factor associated with the presence of hepatic steatosis. CONCLUSIONS: HHE-protein adducts, which are a good marker for oxidative stress, are associated with steatosis in chronic hepatitis C.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Fígado Gorduroso/metabolismo , Hepatite C Crônica/metabolismo , Peroxidação de Lipídeos , Triglicerídeos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Aldeídos/metabolismo , Biomarcadores/metabolismo , Biópsia , Cromatografia Gasosa , Ácidos Graxos Ômega-3 , Fígado Gorduroso/etiologia , Fígado Gorduroso/patologia , Feminino , Hepatite C Crônica/complicações , Hepatite C Crônica/patologia , Humanos , Imuno-Histoquímica , Masculino , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Estresse Oxidativo , Índice de Gravidade de Doença
3.
Hepatol Res ; 26(1): 15-22, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12787799

RESUMO

To assess whether hepatitis C virus infection (HCV) affects type I interferon (IFN) receptor expression, the expression levels of two subunits of this receptor, IFNAR1 and IFNAR2, in peripheral blood mononuclear cells (PBMCs) were determined by flow-cytometric assay in 68 anti-HCV antibody-positive patients (47 positive for HCV RNA and 21 negative for HCV RNA) and 14 healthy controls. The percentages of IFNAR1- and IFNAR2-expressing cells were significantly higher in HCV RNA-positive patients than in HCV RNA-negative patients or healthy controls. In multiple regression analysis, the presence of HCV RNA in serum was independently associated with the expression of both IFNAR1 and IFNAR2 in PBMCs (P=0.007 for IFNAR1 and P=0.003 for IFNAR2). The frequency of IFN-gamma-producing peripheral CD4(+) and CD8(+) cells was also significantly higher in HCV RNA-positive patients than in HCV RNA-negative patients or healthy controls and there was a significant correlation between IFN receptor expression and the frequency of IFN-gamma-producing cells. These results suggest that HCV infection upregulates the expression of the type I IFN receptor in PBMCs through enhanced IFN-gamma production by peripheral CD4(+) and CD8(+) cells as one of mechanisms that regulate the expression of the type I IFN receptor.

4.
J Gastroenterol Hepatol ; 21(8): 1269-75, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16872308

RESUMO

BACKGROUND: Oxidative damage of the erythrocyte membrane plays an important role in ribavirin-induced anemia. The purpose of the present paper was to assess whether supplementation of alpha-tocopherol and ascorbic acid (vitamins) causes changes in the erythrocyte membrane fatty acid composition during interferon and ribavirin combination therapy for chronic hepatitis C patients. METHODS: Fatty acid compositions in erythrocyte membrane phospholipids were determined by gas chromatography at 0, 2, 4, 8 weeks, and at the end of combination therapy (26 weeks) for interferon with ribavirin in 32 patients with chronic hepatitis C who were randomized to receive vitamins or not (controls). RESULTS: Good compliance with orally administered vitamins and ribavirin were confirmed by their concentrations in erythrocytes or plasma. The hemoglobin level was negatively correlated with the ribavirin concentration at 8 weeks (r = 0.59, P = 0.01) after initiation of therapy in controls, but not in the vitamin group. Among the 26 kinds of fatty acids analyzed, only eicosapentaenoic acid (EPA) significantly decreased at 8 weeks after initiation of therapy (P = 0.03) and at the end of therapy (P = 0.004) in controls. Vitamins did not inhibit ribavirin-induced anemia, but attenuated the decrease of EPA in erythrocytes. The EPA level was negatively correlated with the drop in hemoglobin levels at 8 weeks after initiation of therapy in controls (r = 0.58, P = 0.015), but not in the vitamin group. CONCLUSIONS: Supplementation of alpha-tocopherol and ascorbic acid attenuates the ribavirin-induced decrease of EPA in erythrocyte membrane phospholipids in chronic hepatitis C patients.


Assuntos
Ácido Ascórbico/farmacologia , Ácido Eicosapentaenoico/metabolismo , Membrana Eritrocítica/efeitos dos fármacos , Hepatite C Crônica/sangue , Ribavirina/farmacologia , alfa-Tocoferol/farmacologia , Quimioterapia Combinada , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
Gastroenterology ; 130(7): 2087-98, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16762631

RESUMO

BACKGROUND & AIMS: Despite the evidence of hepatic iron overload in patients with chronic hepatitis C, it remains unknown if iron overload is related to hepatocarcinogenesis in this condition. The aim of this study was to determine whether iron overload contributes to development of hepatocellular carcinoma (HCC) in transgenic mice expressing the hepatitis C virus (HCV) polyprotein. METHODS: Male C57BL/6 transgenic mice expressing the HCV polyprotein and nontransgenic littermates were fed an excess-iron diet or control diet. Mice in each group were assessed for altered liver morphology and function and the development of liver tumors. RESULTS: Hepatic iron concentrations in mice fed the excess-iron diet were comparable to those of patients with chronic hepatitis C. There was no inflammation in transgenic and nontransgenic livers. Compared with mice in 3 other groups, transgenic mice fed the excess-iron diet showed marked hepatic steatosis including the centrilobular microvesicular type, ultrastructural alterations of the mitochondria and decreased degradation activity of fatty acid at 6 months, and greater hepatic content of lipid peroxidation products and 8-hydroxy-2'-deoxyguanosine at 12 months after initiation of feeding. The number of proliferating hepatocytes was significantly increased in mice fed the excess-iron diet but was not different between transgenic and nontransgenic mice. Hepatic tumors including HCC developed in 5 of 11 (45%) transgenic mice fed the excess-iron diet but not in mice in other groups at 12 months after initiation of feeding. CONCLUSIONS: Iron overload induces mitochondrial injury and increases the risk of HCC development in transgenic mice expressing the HCV polyprotein.


Assuntos
Carcinoma Hepatocelular/etiologia , Hepacivirus/metabolismo , Sobrecarga de Ferro/complicações , Neoplasias Hepáticas/etiologia , Poliproteínas/metabolismo , Proteínas do Core Viral/análise , Animais , Carcinoma Hepatocelular/patologia , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Hepacivirus/genética , Hepatócitos/citologia , Hepatócitos/metabolismo , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Ferro/metabolismo , Testes de Função Hepática , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Poliproteínas/genética , Probabilidade , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença , Estatísticas não Paramétricas
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