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1.
World J Gastroenterol ; 18(3): 212-24, 2012 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-22294824

RESUMO

Hepatitis C virus (HCV) infection is an important risk factor for insulin resistance (IR). The latter is the pathogenic foundation underlying metabolic syndrome, steatosis and cirrhosis, and possibly hepatocellular carcinoma (HCC). The interplay between genetic and environmental risk factors ultimately leads to the development of IR. Obesity is considered a major risk factor, with dysregulation of levels of secreted adipokines from distended adipose tissue playing a major role in IR. HCV-induced IR may be due to the HCV core protein inducing proteasomal degradation of insulin receptor substrates 1 and 2, blocking intracellular insulin signaling. The latter is mediated by increased levels of both tumour necrosis factor-α (TNF-α) and suppressor of cytokine signaling 3 (SOC-3). IR, through different mechanisms, plays a role in the development of steatosis and its progression to steatohepatitis, cirrhosis and even HCC. In addition, IR has a role in impairing TNF signaling cascade, which in turn blocks STAT-1 translocation and interferon stimulated genes production avoiding the antiviral effect of interferon.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/metabolismo , Hepatite C/tratamento farmacológico , Resistência à Insulina/fisiologia , Adipocinas/metabolismo , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepacivirus/patogenicidade , Humanos , Obesidade/fisiopatologia
2.
Mediators Inflamm ; 2011: 703031, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22007137

RESUMO

OBJECTIVE: Highlighting the apelin system would present a new therapeutic target for liver disease. Apelin; endogenous ligand for the orphan receptor APJ, was recently suggested to be associated with fibrosis progression and cirrhosis in addition to insulin resistance (IR) and inflammation. The present study was conducted to evaluate blood apelin level changes among 73 chronic hepatitis C (CHC) Egyptian patients and if associated with body mass index (BMI), IR, and tumor necrosis factor-alpha (TNF-α). Serum apelin levels were significantly higher in patients with CHC with median value (3.25) when compared with controls (1.11), at P < 0.0001, with significant apelin variations among asymptomatic carriers (ASC), fibrosis, and cirrhosis patients, and also among obese and nonobese patients. Multiple regression analysis depicted that BMI, triglycerides, and total cholesterol were independent correlation factors to apelin levels, whereas TNF-α was found to be significantly negatively correlated to adjusted apelin in CHC patients (r = -0.5944, P < 0.0001). IR was positively correlated to adjusted apelin in CHC patients (r = 0.2663, P < 0.05). CONCLUSION: Apelin level varies among stages of CHC, which may contribute to fibrosis progression. In addition, obesity and IR could act as comorbid factors affecting apelin level in patients with CHC.


Assuntos
Hepatite C Crônica/sangue , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Apelina , Índice de Massa Corporal , Egito , Feminino , Hepatite C Crônica/patologia , Humanos , Resistência à Insulina , Cirrose Hepática/sangue , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Fator de Necrose Tumoral alfa/sangue
3.
Comp Hepatol ; 10(1): 4, 2011 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-21781333

RESUMO

BACKGROUND: To understand the complex and largely not well-understood apoptotic pathway and immune system evasion mechanisms in hepatitis C virus (HCV)-associated hepatocellular carcinoma (HCC) and HCV associated chronic hepatitis (CH), we studied the expression patterns of a number of pro-apoptotic and anti-apoptotic genes (Fas, FasL, Bcl-2, Bcl-xL and Bak) in HepG2 cell line harboring HCV- genotype-4 replication. For confirmation, we also assessed the expression levels of the same group of genes in clinical samples obtained from 35 HCC and 34 CH patients. METHODS: Viral replication was assessed in the tissue culture medium by RT-PCR, quantitative Real-Time PCR (qRT-PCR); detection of HCV core protein by western blot and inhibition of HCV replication with siRNA. The expression level of Fas, FasL, Bcl-2, Bcl-xL and Bak was assessed by immunohistochemistry and RT-PCR whereas caspases 3, 8 and 9 were assessed by colorimetric assay kits up to 135 days post infection. RESULTS: There was a consistent increase in apoptotic activity for the first 4 weeks post-CV infection followed by a consistent decrease up to the end of the experiment. The concordance between the changes in the expression levels of Fas, FasL, Bcl-2, Bcl-xL and Bak in vitro and in situ was statistically significant (p < 0.05). Fas was highly expressed at early stages of infection in cell lines and in normal control liver tissues followed by a dramatic reduction post-HCV infection and an increase in the expression level of FasL post HCV infection. The effect of HCV infection on other apoptotic proteins started very early post-infection, suggesting that hepatitis C modulating apoptosis by modulating intracellular pro-apoptotic signals. CONCLUSIONS: Chronic HCV infection differently modulates the apoptotic machinery during the course of infection, where the virus induces apoptosis early in the course of infection, and as the disease progresses apoptosis is modulated. This study could open a new opportunity for understanding the various signaling of apoptosis and in the developing a targeted therapy to inhibit viral persistence and HCC development.

4.
Hepatol Int ; 4(2): 500-6, 2010 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-20827407

RESUMO

PURPOSE: Egyptian hepatocellular carcinoma (HCC) patients present at advanced stages. We aimed to study the influence of surveillance versus non-surveillance on HCC staging and the potential therapeutic options. METHODS: A retrospective study to evaluate the effect of surveillance on early detection of HCC among cirrhotic patients from 2003 to 2008. Patients examined every 6 months using ultrasound and α-fetoprotein (α-FP) (group A) and those diagnosed with those that present for the first time symptomatically or incidentally (group B). Groups were compared for α-FP level, tumour characteristics, severity of liver disease; tumour staging was evaluated by Okuda, CLIP and BCLC staging systems, in addition to the potential therapeutic options. RESULTS: Group A comprised 122 HCC cases and group B 473. Surveillance improved HCC detection: at the stage of single nodule in 62.3% in group A versus 52.2% in group B, (P = 0.046) and reduced the percentage of HCC with portal vein thrombosis in 16.4 versus 33.8%, (P = 0.000) and the percentage of α-FP >400 ng/ml in 19.5 versus 32.6%, (P = 0.006) in groups A and B, respectively. Surveillance doubled the detection of HCC at early stage of BCLC (25.4 vs. 11.9% P = 0.000) and doubled the patients' chance for loco-regional ablation (12.3 vs. 5.9%, P = 0.015) and liver transplantation (10.7 vs. 3.2%, P = 0.001) in groups A and B, respectively. CONCLUSION: HCC surveillance increases early detection of HCC and doubled the chances for curative options. Implementation of both HCC surveillance and cadaveric liver transplantation programs should be recommended in Egypt.

5.
Vaccine ; 28(52): 8338-44, 2010 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-19995542

RESUMO

INTRODUCTION: The highest estimated prevalence of HCV infection has been reported in Egypt, nearly 12% mostly type 4. Currently, a commercial vaccine to protect this high risk population as well as global HCV infected patients is not available. OBJECTIVES: In the present study, we aim at: (1) examining the viral binding capacities of purified monospecific polyclonal murine antibodies raised against genetically conserved viral protein sequences, i.e. synthetic peptides derived from those sequences located within envelope proteins and (2) assessment of immunogenic properties and safety parameters of those peptides individually and in a vaccine format in mice. METHODS: Purified IgG Abs from immunized mice were used in immunocapture RT-PCR experiments to test viral neutralization by Abs raised against each of 4 peptides termed p35 (E1), p36 (E2), p37 (E2) and p38 (E2). Swiss mice were immunized with each of the 3 peptides (p35, p37 and p38) which generated neutralizing antibodies in immunocapture experiments. Antibody responses to corresponding peptides were determined using different routes of administration, different adjuvants, different doses and at different time points post-injection. To explore the dose range for future pharmacological studies, three doses namely 50 ng, 10 µg and 50 µg/25 gm mouse body weight were tested for biochemical and histopathological changes in several organs. RESULTS: Murine Abs against p35, p37 and p38 but not p36 showed HCV neutralization in immunocapture experiments. Subcutaneous injection of peptides elicited higher responses than i.m. and i.p. Immunization with Multiple Antigenic Peptide (MAP) form or coupled to Al PO4 elicited the highest Ab responses. Peptide doses of 50 ng/25 gm body weight or less were effective and safe, however dose assessment still requires further study. Histopathological changes were observed in animals that received doses ∼1000 times higher than the potential therapeutic dose. CONCLUSION: Exploration of humoral immunogenicity, neutralization capacity and safety suggested that the peptides presented herein are candidate vaccine components for further preclinical assessment.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Anti-Hepatite C/sangue , Proteínas do Envelope Viral/imunologia , Vacinas contra Hepatite Viral/imunologia , Animais , Feminino , Masculino , Camundongos , Vacinação/métodos , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/efeitos adversos , Vacinas de Subunidades Antigênicas/imunologia , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/toxicidade , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/efeitos adversos
6.
World J Gastroenterol ; 15(40): 4993-9, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19859990

RESUMO

Several studies have demonstrated that the outcome of chronic hepatitis C (CHC) infection is profoundly influenced by a variety of comorbidities. Many of these comorbidities have a significant influence on the response to antiviral therapy. These comorbidities negatively affect the course and outcome of liver disease, often reducing the chance of achieving a sustained virological response with PEGylated interferon and ribavirin treatments. Comorbidities affecting response to antiviral therapy reduce compliance and adherence to inadequate doses of therapy. The most important comorbidities affecting the course of CHC include hepatitis B virus coinfection, metabolic syndrome, and intestinal bacterial overgrowth. Comorbidities affecting the course and response to therapy include schistosomiasis, iron overload, alcohol abuse, and excessive smoking. Comorbidities affecting response to antiviral therapy include depression, anemia, cardiovascular disease, and renal failure.


Assuntos
Gastroenterologia/métodos , Hepatite C/complicações , Hepatite C/terapia , Alcoolismo/complicações , Antivirais/farmacologia , Comorbidade , Humanos , Interferons/uso terapêutico , Sobrecarga de Ferro/complicações , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Esquistossomose/complicações , Fumar , Resultado do Tratamento
7.
Am J Gastroenterol ; 104(4): 906-11, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19293791

RESUMO

OBJECTIVES: A subgroup of HBeAg-negative chronic hepatitis B (CHB) patients with alanine aminotransferase (ALT) and/or hepatitis B virus (HBV)-DNA levels below the cutoff values of international guidelines may have significant liver disease and miss the opportunity for early treatment. Histopathological changes of HBeAg-negative CHB patients at initial presentation irrespective of HBV-DNA and/or ALT levels to increase the likelihood of patients for treatment are evaluated. METHODS: CHB patients attending Cairo Liver Center from January 2006 to May 2008 had biochemical, serological, and virological screening as well as liver biopsy that was assessed by Metavir score. RESULTS: Fifty-two HBeAg-negative CHB patients (46 male and 6 female) with a median age of 37.5 years were included in the study. Significant fibrosis (>or=F2) was found in 26% (5/19) of patients with serum HBV-DNA <2,000 IU/ml, and 53% (21/40) of patients with ALT level <2xULN. Liver biopsy increased candidacy for treatment by nearly 25% before implementation of the recommended lower ALT levels (30 U/l for male and 19 U/l for female patients), and by 21.2% after implementation of the lower ALT level. Implementation of the lower ALT level increased the candidacy of patients for treatment by 4% (two patients), whereas liver biopsy increased eligibility for treatment by 55.8 % (27/49). CONCLUSIONS: Liver biopsy is more reliable than either ALT or HBV-DNA levels in the decision to treat Egyptian HBeAg-negative CHB patients, even with the implementation of the recommended lower ALT levels.


Assuntos
Biópsia por Agulha/métodos , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/patologia , Interferons/uso terapêutico , Fígado/patologia , Adulto , DNA Viral/análise , Diagnóstico Diferencial , Egito/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/epidemiologia , Humanos , Incidência , Fígado/virologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
8.
World J Gastroenterol ; 12(38): 6098-101, 2006 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-17036378

RESUMO

Smoking causes a variety of adverse effects on organs that have no direct contact with the smoke itself such as the liver. It induces three major adverse effects on the liver: direct or indirect toxic effects, immunological effects and oncogenic effects. Smoking yields chemical substances with cytotoxic potential which increase necro-inflammation and fibrosis. In addition, smoking increases the production of pro-inflammatory cytokines (IL-1, IL-6 and TNF- alpha) that would be involved in liver cell injury. It contributes to the development of secondary polycythemia and in turn to increased red cell mass and turnover which might be a contributing factor to secondary iron overload disease promoting oxidative stress of hepatocytes. Increased red cell mass and turnover are associated with increased purine catabolism which promotes excessive production of uric acid. Smoking affects both cell-mediated and humoral immune responses by blocking lymphocyte proliferation and inducing apoptosis of lymphocytes. Smoking also increases serum and hepatic iron which induce oxidative stress and lipid peroxidation that lead to activation of stellate cells and development of fibrosis. Smoking yields chemicals with oncogenic potential that increase the risk of hepatocellular carcinoma (HCC) in patients with viral hepatitis and are independent of viral infection as well. Tobacco smoking has been associated with suppression of p53 (tumour suppressor gene). In addition, smoking causes suppression of T-cell responses and is associated with decreased surveillance for tumour cells. Moreover, it has been reported that heavy smoking affects the sustained virological response to interferon (IFN) therapy in hepatitis C patients which can be improved by repeated phlebotomy. Smoker's syndrome is a clinico-pathological condition where patients complain of episodes of facial flushing, warmth of the palms and soles of feet, throbbing headache, fullness in the head, dizziness, lethargy, prickling sensation, pruritus and arthralgia.


Assuntos
Fígado/patologia , Fumar/efeitos adversos , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/patologia , Humanos , Interferons/uso terapêutico , Processos Neoplásicos , Policitemia/etiologia , Fumaça/análise , Fumar/imunologia , Nicotiana/química
9.
Am J Gastroenterol ; 100(11): 2447-52, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16279899

RESUMO

BACKGROUND AND AIM: Currently, pegylated interferon is the most effective therapy for hepatitis C but its cost is out of reach of most patients in the developing countries. The aim of this study was to assess the response rate of genotype-4 patients to 24 wks of peg-interferon-alpha2b (Peg-IFN-alpha2b) and ribavirin (RBV) or interferon-alpha2b (IFN-alpha2b) with RBV and amantadine (AMD) as an alternative option. METHODS: In a controlled study, 180 biopsy-proven naïve chronic hepatitis C patients were allocated into three groups based on their financial affordability to any of the study regimens. Group I (control) comprised 40 patients who received Peg-IFN-alpha2b in a flat dose of 100 mug/wk (the dose available in Egypt) plus RBV 1,000-1,200 mg per day based on body weight for 48 wks. Group II comprised 70 patients who received the same regimen for 24 wks. Group III comprised 70 patients who received induction-dose triple therapy (IDTT) in the form of IFN-alpha2b 3 MU once daily for the first 4 wks then reduced to TIW for 20 wks plus RBV 1,000-1,200 mg per day based on body weight and AMD 100 mg twice daily for 24 wks. Six patients from group I, eight patients from group II, and four from group III discontinued the study either due to financial limitations and/or intolerable adverse effects of the drugs. RESULTS: Intention-to-treat analysis revealed that sustained virological response (SVR) achieved in 22 (55.0%), 34 (48.6%), and 20 (28.6%) in groups I, II, and III, respectively. Adherence-to-treatment analysis (80/80/80) revealed that SVR achieved in 22 (64.7%), 34 (54.8%), and 20 (30.3%) in groups I, II, and III, respectively. In absence of eradication of hepatitis-C-virus-RNA at week 12, there was virtually no chance of achieving SVR. These data collectively may indicate that genotype 4 is "not difficult to treat" as previously reported. CONCLUSION: Response of genotype-4 patients to 24 wks of Peg-IFN-alpha2b/RBV did not significantly differ from 48 wks, but was significantly higher than IDTT. Although SVR achieved by IDTT is less than Peg-IFN-alpha, yet it might provide a second option when the latter is not affordable. Early virological response should be used as a predictor to SVR to avoid unnecessary expenses in nonresponders patients.


Assuntos
Amantadina/uso terapêutico , Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Amantadina/administração & dosagem , Amantadina/economia , Antivirais/administração & dosagem , Antivirais/economia , Portadores de Fármacos , Combinação de Medicamentos , Custos de Medicamentos , Feminino , Seguimentos , Genótipo , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/economia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis , RNA Viral/sangue , Proteínas Recombinantes , Ribavirina/administração & dosagem , Ribavirina/economia , Fatores de Tempo , Resultado do Tratamento
10.
World J Gastroenterol ; 11(33): 5193-8, 2005 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16127751

RESUMO

AIM: To identify the trend, possible risk factors and any pattern change of hepatocellular carcinoma (HCC) in Egypt over a decade. METHODS: All HCC patients attending Cairo Liver Center between January 1993 and December 2002, were enrolled in the study. Diagnosis of HCC was based on histopathological examination and/or detection of hepatic focal lesions by two imaging techniques plus alpha-fetoprotein level above 200 ng/mL. The duration of the study was divided into two periods of 5 years each; period I (1993-1997) and period II (1998-2002). Trend, demographic features of patients (age, gender, and residence), risk factors (HBsAg, HCV-Ab, schistosomiasis and others) and pattern of the focal lesions were compared between the two periods. Logistic regression model was fitted to calculate the adjusted odds ratios for the potential risk factors. The population attributable risk percentage was calculated to estimate the proportion of HCC attributed to hepatitis B and C viral infections. RESULTS: Over a decade, 1328 HCC patients out of 22,450 chronic liver disease (CLD) patients were diagnosed with an overall proportion of 5.9%. The annual proportion of HCC showed a significant rising trend from 4.0% in 1993 to 7.2% in 2002 (P = 0.000). A significant increase in male proportion from 82.5% to 87.6% (P = 0.009); M/F from 5:1 to 7:1 and a slight increase of the predominant age group (40-59 years) from 62.6% to 66.8% (P = 0.387) in periods I and II respectively, reflecting a shift to younger age group. In the bivariate analysis, HCC was significantly higher in rural residents, patients with history of schistosomiasis and/or blood transfusion. Yet, after adjustment, these variables did not have a significant risk for development of HCC. There was a significant decline of HBsAg from 38.6% to 20.5% (P = 0.000), and a slight increase of HCV-Ab from 85.6% to 87.9% in periods I and II respectively. HBV conferred a higher risk to develop HCC more than HCV in period I (OR 1.9 vs 1.6) and period II (OR 2.7 vs 2.0), but the relative contribution of HBV for development of HCC declined in period II compared to period I (PAR% 4.2%, 21.32%). At presentation, diagnostic alpha-fetoprotein level (> or = 200 ng/mL) was demonstrated in 15.6% vs 28.9% and small HCC (< or = 3 cm) represented 14.9% vs 22.7% (P = 0.0002) in periods I and II respectively. CONCLUSION: Over a decade, there was nearly a twofold increase of the proportion of HCC among CLD patients in Egypt with a significant decline of HBV and slight increase of HCV as risk factors. Alpha-fetoprotein played a limited role in diagnosis of HCC, compared to imaging techniques. Increased detection of small lesions at presentation reflects increased awareness of the condition.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Neoplasias Hepáticas/epidemiologia , Adulto , Distribuição por Idade , Idoso , Egito/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Distribuição por Sexo
11.
Liver Int ; 25(4): 746-51, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15998425

RESUMO

OBJECTIVES: Interferon (IFN) therapy is not affordable by the majority of Egyptian patients. Our aim was to tailor an effective and inexpensive regimen that ameliorates hepatic necro-inflammatory activity among chronic hepatitis C (CHC) patients. METHODS: One hundred and seventy naïve CHC patients with elevated alanine aminotransferase (ALT) (>1.5-fold) and detectable hepatitis C virus (HCV)-RNA by polymerase chain reaction, who cannot afford IFN-based therapy were randomly allocated either to non-interferon-based therapy (N-IFN-BT) (group I) or silymarin therapy (group II). Group I comprised 87 patients (biopsy proved chronic hepatitis in 62 patients) who were administered a daily combination of ribavirin (600-800 mg) plus amantadine (200 mg) and ursodeoxycholic acid (UDCA) (500 mg) for 24 weeks. Group II comprised 83 patients who were administered Silymarin 450 mg/day for 24 weeks. RESULTS: Statistical evaluation was conducted on 82 patients from group I and 72 from group II because of the withdrawal of five and 11 patients from Groups I and II, respectively. Age, sex, social status and biochemical parameters were comparable in both groups. Normalization of ALT at the end of treatment was achieved in 58.5% and 15.3% (P<0.001), whereas end of treatment virologic response (ETVR) was achieved in 2.4% and 0% of Groups I and II, respectively. Twenty-four weeks after cessation of therapy, sustained biochemical response (SBR) was achieved in 28% and 2.8% (P<0.001), while sustained virologic response (SVR) was maintained in 2.4% and 0% of the patients in Groups I and II, respectively. In Group I, histopathological examination revealed a decreased activity index by an average score of 1.5 points among 38/62 of the rebiopsied patients. CONCLUSION: Twenty-four weeks N-IFN-BT achieved a fourfold-higher ETBR and a tenfold-higher SBR compared with silymarin therapy, which reflects an improvement of necroinflammatory activity as proven by repeat histopathology.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferons , Fígado/efeitos dos fármacos , Substâncias Protetoras/uso terapêutico , Silimarina/uso terapêutico , Alanina Transaminase/análise , Amantadina/uso terapêutico , Quimioterapia Combinada , Feminino , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Interferons/economia , Interferons/uso terapêutico , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Necrose , RNA Viral/análise , Ribavirina/uso terapêutico , Resultado do Tratamento , Ácido Ursodesoxicólico/uso terapêutico
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