Serum levels of interleukin-9 during acute rejection in liver transplantation.

INTRODUCTION: Interleukin-9 (IL-9) has been cast as a player in autoimmunity, but its role in liver transplantation remains to be clarified. The aim of our study was to investigate the time course of IL-9 serum levels during hepatic allograft rejection. METHODS: IL-9 serum levels were determined in 34 healthy subjects and 50 hepatic transplant recipients. The patients were divided into two groups: group I was composed of 15 patients with acute rejection episodes, and group II, 35 patients free of this problem. Samples were collected on days 1 and 7 after liver transplantation and on the day of liver biopsy. RESULTS: The concentrations of IL-9 were similar in the rejection and nonrejection groups over the entire postoperative period. The whole transplant group, including those with stable graft function, showed higher IL-9 serum levels than the controls at all times after liver transplantation. CONCLUSIONS: These preliminary results suggest a lack of participation of IL-9 in human liver allograft rejection.

Interleukin-9 in stable liver transplant recipients.

INTRODUCTION: Interleukin-9 (IL-9) has recently been described to be involved in the maintenance of a tolerant environment, but there is no evidence of its role in human liver transplantation. The aim of our study was to measure the serum levels of IL-9 in stable liver transplant recipients and examine their influence on immunosuppressant load. METHODS: Serum IL-9 levels were determined in 34 healthy subjects and 30 stable liver transplant recipients who were free of rejection episodes for at least 8 years. The results were analyzed according to the blood levels of calcineurin inhibitors (CNIs) at the time of the study: 13 patients showed high concentrations of either cyclosporine or tacrolimus (high CNI: cyclosporine > 80 ng/mL or tacrolimus > 5 ng/mL) and another 17 patients showed low CNI levels. RESULTS: The concentrations of IL-9 were significantly higher among liver transplant recipients compared with healthy subjects. In addition, patients with low CNI blood levels showed higher serum levels of IL-9, an effect that was greater with tacrolimus, albeit not significantly. CONCLUSIONS: These preliminary results indicated that increased serum IL-9 concentrations accompanied a lower immunosuppressive load. It remains to be established whether this relates to induction of tolerance in liver transplantation.

Liver transplantation with donors older than 75 years.

INTRODUCTION: Orthotopic liver transplantation has shown successful results over the last years. For this reason there are increased numbers of patients on waiting lists. To expand the pool of liver donors, elderly donors have been used as a strategy. OBJECTIVE: We report our experience comparing donors of ≥ 75 years with younger ages for their characteristics, clinical outcomes, and survivals. METHODS: From January 2001 to December 2009, we performed 174 consecutive liver transplantation from cadaveric donors in 166 patients. During this period, we used 24 liver grafts from donors ≥ 75 years. We analyzed their outcomes retrospectively, describing donors and recipient characteristics and their clinical evolution. RESULTS: The mean follow-up time among the entire study population was 42 ± 39 months. We observed an overall survival of 68.3% with similar incidences in both groups: 83% in the younger versus 78% in the older group at 1 year, and 69% versus 63%, at 5 years respectively. Both groups showed similar lengths of intensive care unit stay, cold and warm ischemia times, and intraoperative transfusion requirements. The older group had a total operative time than was longer and fewer hypotensive episodes than the younger group. There were no significant differences in the rates of rejection and retransplantation between the groups. The use of older donor livers was associated with a significantly higher rate of poor initial graft function (P = .027), an increased number of reinterventions (P = .013) in the older donor group, as well as more frequent vascular and biliar complications, without reaching significance. CONCLUSION: Our data suggested that donor age alone did not engendered a survival disadvantage for graft or recipient. However, careful donor selection is needed to avoid additional risk factors that can increase the morbidity or mortality of the procedure.

Effect of immunosuppressant blood levels on serum concentration of interleukin-17 and -23 in stable liver transplant recipients.

INTRODUCTION: T(H)17 cells have been recently described to be involved in inflammatory and immune-mediated diseases, but there is no evidence of their role in human liver transplantation. Interleukin (IL)-23 is considered an inducer cytokine, whereas IL-17 is the main cytokine released by T(H)17 cells. The aim of our study was to measure the serum levels of IL-17 and IL-23 in stable liver transplant recipients and examine the influence of immunosuppressant concentrations. MATERIALS AND METHODS: Serum levels of IL-23 and IL-17 were determined in 38 healthy subjects and 35 stable hepatic transplant recipients who were free of rejection episodes for at least 8 years. The results were analyzed according to the simultaneous blood levels of cyclosporine (n = 20) or tacrolimus (n = 15). RESULTS: No significant differences were observed in the serum levels of IL-17 and IL-23 between healthy subjects and transplanted patients. In addition, patients with low blood levels of tacrolimus (<6 ng/mL), but not cyclosporine, showed significantly lower serum levels of the 2 cytokines. CONCLUSION: These preliminary results suggested a lack of activation of the T(H)17 pathway, which was more pronounced among the patient subgroup treated with tacrolimus.

[Gene expression in obese patients with non-alcoholic steatohepatitis]. / Expresión génica en pacientes obesos con enfermedad hepática por depósito de grasa.

UNLABELLED: Although the molecular basis for the pathophysiology of non-alcoholic steatohepatitis (NASH) is poorly understood, we evaluate the hepatic gene expression of cytokines, chemokines, cell receptors, growth factors, intracellular transducers and extracellular communication proteins in liver tissue of obese patients (with and without NASH), and we determine the specific intrahepatic gene expression profiles associated with histological severe NASH.Thirty-eight obese patients with BMI > 35 were analyzed, who underwent bariatric surgery. Biopsy specimen samples were snap-frozen in liquid nitrogen. Hepatic gene expression was determined in liver biopsy specimens from 3 groups: a) obese patients without NASH (n = 12); b) patients with NASH without fibrosis (n = 13); and c) patients with NASH and fibrosis (n = 13). Genes were considered to be expressed differentially in NASH only if there was a greater than 2-fold difference in abundance of mRNA when compared with each of the control group. These results were confirmed by real-time PCR. Fourteen genes were differentially expressed (10 overexpressed and 4 underexpressed) in patients with NASH. Genes that were significantly overexpressed included prohibitin, TNF, TNF RI (p55), MCSF, R2-TRAIL, b1-CTGF, FGF, VEGF, and BIGH3OBR. Insulin growth factor-1, insulin growth factor-2, interleukin-2 and tyrosine-receptor were underexpressed in NASH patients. IN CONCLUSION: 1. The obese patients with NASH without fibrosis show an overexpression of proinflammatory and proapoptotic genes. Also, the NASH patients with fibrosis show an overexpression of fibrogenic genes, including the leptin receptor Ob-Rb.2. The up-regulated gene expression of prohibitin suggests mitochondrial dysfunction in NASH patients.

Expresión génica en pacientes obesos con enfermedad hepática por depósito de grasa / No disponible

La fisiopatología de la enfermedad hepática por depósito de grasasólo se conoce de forma parcial. En este trabajo hemos analizadola expresión génica intrahepática de citoquinas, quimioquinas, receptorescelulares, factores de crecimiento, transductores de señalesintracelulares y proteínas de comunicación extracelular en el tejidohepático de sujetos obesos con y sin esteatohepatitis no alcohólica,en un intento de determinar un perfil de expresión génica asociadoa las formas severas de la esteatohepatitis no alcohólica (EHNA).Se analizó un grupo de 38 pacientes obesos con un IMC > 35,que fueron sometidos a cirugía bariátrica. La expresión génica intrahepáticase determinó en el tejido hepático dividiendo a los pacientesen tres grupos: a) pacientes obesos sin datos histológicos sugestivosde EHNA (n = 12); b) pacientes con EHNA sin fibrosis (n =13); y c) pacientes con EHNA y fibrosis (n = 13). Se consideró queexistía una sobreexpresión génica cuando la diferencia en la expresiónera, al menos, de dos veces con respecto al grupo control. Losresultados se confirmaron mediante PCR en tiempo real. Se detectóuna expresión diferencial de 14 genes (10 sobreexpresados y 4infraexpresados). Los genes sobreexpresados incluyeron prohibitina,TNF, TNF RI (p55), MCSF, R2-TRAIL, TGF-b1, CTGF, FGF,VEGF, BIGH3 y ObRb. La expresión de los genes insulin growthfactor-1, insulin growth factor-2, interleuquina-2 y tyrosine-receptorfue menor que en el grupo control.En conclusión:1. Los pacientes obesos con EHNA sin fibrosis muestran unasobreexpresión de genes proinflamatorios y proapoptóticos. Enlos pacientes con EHNA y fibrosis, se observa, además, una sobreexpresiónde genes profibrogénicos, incluyendo el gen del receptorde la leptina.2. La expresión de prohibitiva en los pacientes con EHNA,tanto con fibrosis como sin fibrosis, fue superior que en los controles,lo que sugiere una disfunción mitocondrial en los pacientescon EHNA

Although the molecular basis for the pathophysiology of nonalcoholicsteatohepatitis (NASH) is poorly understood, we evaluatethe hepatic gene expression of cytokines, chemokines, cell receptors,growth factors, intracellular transducers and extracellularcommunication proteins in liver tissue of obese patients (with andwithout NASH), and we determine the specific intrahepatic geneexpression profiles associated with histological severe NASH.Thirty-eight obese patients with BMI > 35 were analyzed, whounderwent bariatric surgery. Biopsy specimen samples were snapfrozenin liquid nitrogen. Hepatic gene expression was determinedin liver biopsy specimens from 3 groups: a) obese patientswithout NASH (n = 12); b) patients with NASH without fibrosis (n= 13); and c) patients with NASH and fibrosis (n = 13). Geneswere considered to be expressed differentially in NASH only ifthere was a greater than 2-fold difference in abundance of mRNAwhen compared with each of the control group. These resultswere confirmed by real-time PCR. Fourteen genes were differentiallyexpressed (10 overexpressed and 4 underexpressed) in patientswith NASH. Genes that were significantly overexpressed includedprohibitin, TNF, TNF RI (p55), MCSF, R2-TRAIL,b1-CTGF, FGF, VEGF, and BIGH3OBR. Insulin growth factor-1,insulin growth factor-2, interleukin-2 and tyrosine-receptor wereunderexpressed in NASH patients.In conclusion:1. The obese patients with NASH without fibrosis show anoverexpression of proinflammatory and proapoptotic genes.Also, the NASH patients with fibrosis show an overexpression offibrogenic genes, including the leptin receptor Ob-Rb.2. The up-regulated gene expression of prohibitin suggestsmitochondrial dysfunction in NASH patients

Increased expression of Ob-Rb and its relationship with the overexpression of TGF-beta1 and the stage of fibrosis in patients with nonalcoholic steatohepatitis.

AIMS: The main aim of this study was to examine the relationship of the leptin system in steatosis and nonalcoholic steatohepatitis (NASH). The study also analysed the pathogenic role of the leptin system in the development of hepatic fibrosis and its relation with the TGF-beta1 system. MATERIALS AND METHODS: The study included 90 subjects, 55 with NASH and 35 with simple steatosis. Gene expression of leptin, leptin receptor and TGF-beta mRNA was analysed by real-time PCR on liver tissue. Leptin serum levels were determined by RIA. Leptin receptor expression was also assessed by immunohistochemistry. RESULTS: Increased expression was found for leptin receptor mRNA (P=0.0016) and its protein (P<0.05) in patients with NASH, especially those with fibrosis. There was a marked increase in gene expression of TGF-beta1 in patients with NASH (P=0.0002). A strong correlation was demonstrated between leptin receptor gene expression and TGF-beta1 gene expression (P=0.023). No leptin expression was found in the liver tissue. All patients showed a marked hyperleptinemia, which was closely related to the anthropometric characteristics analysed and independent of development or not of NASH. CONCLUSIONS: The results of the study demonstrate for the first time increased leptin receptor expression in liver tissue and its relationship with overexpression of TGF-beta1 and the degree of hepatic fibrosis.

Papel del sobrecrecimiento bacteriano intestinal y de la motilidad intestinal en la traslocación bacteriana en un modelo experimental de cirrosis / Role of intestinal bacterial overgrowth and intestinal motility in bacterial translocation in experimental cirrhosis

Introducción: el sobrecrecimiento bacteriano intestinal (SBI) está relacionado con la motilidad del intestino delgado y diferentes trabajos con modelos experimentales han sugerido su relación con el desarrollo de traslocación bacteriana (TB). Tanto el sobrecrecimientobacteriano intestinal como la traslocación bacteriana soneventos frecuentes en la cirrosis hepática. Objetivos: los objetivos de este estudio han sido analizar lapoblación cecal de bacterias aerobias y el tránsito intestinal en un modelo de ratas cirróticas y su relación con la TB. Material y métodos: el estudio se ha realizado en un modelo experimental de cirrosis inducida por tetracloruro de carbono por vía oral en ratas Sprague-Dawley. Se llevaron a cabo cultivos microbiológicosconvencionales a partir de ganglios linfáticos mesentéricos (GLM), sangre portal y periférica, hígado, bazo, y muestras cecales de todos los animales. Además se determinó el tiempo de tránsito intestinal en 10 ratas cirróticas y en 10 controles. Resultados: la prevalencia de la traslocación bacteriana en los animales cirróticos fue de un 56%. La población de gérmenes aerobios en el ciego en las ratas cirróticas fue significativamentemayor (p < 0,01) que en las ratas controles. Las ratas cirróticas con TB presentaron un población bacteriana intestinal más elevada que las ratas sin TB (p < 0,05). La prevalencia de SBI en los animales cirróticos fue de un 67% frente a un 0% en los animales control (p < 0,01); también el SBI fue más frecuente en las ratas cirróticas con TB que en las cirróticas sin TB (93 vs. 33%) (p <0,01). De las bacterias que traslocaron un 95,6% presentaban sobrecrecimiento en ciego. El tránsito intestinal fue más lento en las ratas cirróticas (60,5 ± 12,7 vs. 81,2 ± 5,7 cm) que en los animales controles (p < 0,01). Conclusiones: estos resultados sugieren que el sobrecrecimiento bacteriano es frecuente en ratas cirróticas y predispone al desarrollo de traslocación bacteriana intestinal. Además, este sobrecrecimientoprobablemente está favorecido por la existencia deuna dismotilidad intestinal, frecuente en este modelo de cirrosis experimental

Background: intestinal bacterial overgrowth (IBO) is related to small bowel motility and has been involved in the pathogenesis of bacterial translocation (BT) in experimental models, and both overgrowing gut flora and translocating bacteria to mesenteric lymph nodes are common features in cirrhosis. Objectives: the aims of this study were to analyze cecal aerobic bacteria and intestinal transit in cirrhotic rats, and their relationship with BT, evaluating the role of intestinal bacterial overgrowth and small bowel dismotility in the development of BT in experimental cirrhosis. Material and methods: we included twenty-seven male Sprague-Dawley rats with carbon tetrachloride-induced cirrhosis without ascites and ten controls. Cultures of mesenteric lymph nodes (MLN), peripheral and portal blood, liver, spleen and cecal samples were carried out. Small intestinal transit was determined in ten cirrhotic rats and in ten control rats. Results: the prevalence of bacterial translocation was 56%. Total cecal aerobic bacteria count was significantly higher in cirrhotic rats than in control rats (p < 0.001). Cirrhotic rats with translocated bacteria had higher total aerobic intestinal counts than culture-negative MLN bacteria (p < 0.05). The prevalence of total intestinal bacterial overgrowth in cirrhotic animals was 67%, and 0% in control animals (p < 0.001). According to BT, total IBO was more frequent in cirrhotic rats with BT versus those without BT (93 vs. 33%) (p < 0.001). Of the translocating bacteria, 95.6% were found to be overgrown in the cecum. The mallintestinal transit was slower in cirrhotic rats (60.5 ± 12.7 cm vs. 81.2 ± 5.7 cm) than in control animals (p < 0.001). Conclusions: these results suggest that the increase of intestinal aerobic bacteria in experimental cirrhosis is associated with translocation. In addition, IBO is frequent in cirrhotic rats, and is supposed to play an important role in the development of BT. Impaired motility of the small intestine is a common feature in cirrhosis and may be implicated in the pathogenesis of IBO

Adiponectin and its receptors in non-alcoholic steatohepatitis.

BACKGROUND: Adiponectin, an adipocyte derived polypeptide, has been shown to alleviate steatosis and inflammation in mice with non-alcoholic fatty liver disease. AIM: In the present study, we wished to define liver expression of adiponectin and its receptors in morbidly obese patients undergoing bariatric surgery. Patients with non-alcoholic steatohepatitis (NASH) or simple steatosis were investigated to test whether dysregulation of this system might be involved in these disorders. PATIENTS AND METHODS: Liver mRNA expression of adiponectin and its recently cloned receptors RI and RII (adipoRI and adipoRII) were analysed by fluorescence based real time polymerase chain reaction in 13 patients with NASH and nine with simple steatosis. Adiponectin and adipoRII protein expression were assessed by immunohistochemistry in a subgroup of patients. RESULTS: Adiponectin and adipoRII mRNA expression were significantly reduced in liver biopsies of patients with NASH compared with simple steatosis while no difference was found in adipoRI mRNA expression. In NASH, adipoRII mRNA expression was negatively correlated with serum aspartate aminotransferase levels, serum alanine aminotransferase levels, and grade of fibrosis. Liver adiponectin protein expression was mainly found in endothelial cells of portal vessels and liver sinusoids whereas adipoRII expression was seen in hepatocytes only. Adiponectin and adipoRII staining were lower in biopsies of subjects with NASH compared with simple steatosis. CONCLUSION: Reduced hepatic expression of adiponectin and adipoRII might be of pathophysiological relevance in non-alcoholic fatty liver diseases.

Role of intestinal bacterial overgrowth and intestinal motility in bacterial translocation in experimental cirrhosis.

BACKGROUND: Intestinal bacterial overgrowth (IBO) is related to small bowel motility and has been involved in the pathogenesis of bacterial translocation (BT) in experimental models, and both overgrowing gut flora and translocating bacteria to mesenteric lymph nodes are common features in cirrhosis. OBJECTIVES: The aims of this study were to analyze cecal aerobic bacteria and intestinal transit in cirrhotic rats, and their relationship with BT, evaluating the role of intestinal bacterial overgrowth and small bowel dismotility in the development of BT in experimental cirrhosis. MATERIAL AND METHODS: We included twenty-seven male Sprague-Dawley rats with carbon tetrachloride-induced cirrhosis without ascites and ten controls. Cultures of mesenteric lymph nodes (MLN), peripheral and portal blood, liver, spleen and cecal samples were carried out. Small intestinal transit was determined in ten cirrhotic rats and in ten control rats. RESULTS: The prevalence of bacterial translocation was 56%. Total cecal aerobic bacteria count was significantly higher in cirrhotic rats than in control rats (p < 0.001). Cirrhotic rats with translocated bacteria had higher total aerobic intestinal counts than culture-negative MLN bacteria (p < 0.05). The prevalence of total intestinal bacterial overgrowth in cirrhotic animals was 67%, and 0% in control animals (p < 0.001). According to BT, total IBO was more frequent in cirrhotic rats with BT versus those without BT (93 vs. 33%) (p < 0.001). Of the translocating bacteria, 95.6% were found to be overgrown in the cecum. The small-intestinal transit was slower in cirrhotic rats (60.5 +/- 12.7 cm vs. 81.2 +/- 5.7 cm) than in control animals (p < 0.001). CONCLUSIONS: These results suggest that the increase of intestinal aerobic bacteria in experimental cirrhosis is associated with translocation. In addition, IBO is frequent in cirrhotic rats, and is supposed to play an important role in the development of BT. Impaired motility of the small intestine is a common feature in cirrhosis and may be implicated in the pathogenesis of IBO.

Fiebre, dolor en hipocondrio derecho y masa hepática con calcificación central / Fever, pain in right hypochondrium and liver mass with central calcification

No disponible

[Triple immunosuppressive therapy in the treatment of severe ulcerative colitis]. / Triple terapia inmunosupresora en el tratamiento de la colitis ulcerosa grave.

INTRODUCTION: Severe episodes of steroid-refractory ulcerative colitis (UC) were considered an indication for surgery until the introduction of new immunosuppressive agents such as cyclosporine. OBJECTIVES: 1) To confirm the efficacy of intravenous cyclosporine in inducing remission in severe episodes of steroid-refractory UC; 2) To analyze the efficacy of triple immunosuppressive therapy with cyclosporine, azathioprine and prednisone in the maintenance of remission induced by intravenous cyclosporine. PATIENTS AND METHOD: Fourteen patients diagnosed with a severe episode of steroid-refractory UC were treated with intravenous cyclosporine at a dose of 4 mg/kg/day. In all patients, after response was induced, this regimen was substituted by oral cyclosporine plus azathioprine at a dose of 2-2.5 mg/kg/day and decreasing doses of corticoids. Neoral cyclosporine was progressively reduced until discontinuation within 3 months, coinciding with a simultaneous decrease of oral steroids. RESULTS: All patients showed response to intravenous cyclosporine with a significant reduction in the Truelove index calculated before and after treatment. After remission was induced, all patients followed triple immunosuppressive therapy for 3 months. In the follow-up for a mean of 24 months (range: 14-34) only two patients required admission for a new episode of UC and colectomy was finally indicated in only one. None of the 14 patients treated with cyclosporine showed severe adverse effects attributable to the drug. CONCLUSIONS: Intravenous cyclosporine is a safe and effective alternative in the treatment of severe episodes of steroid-refractory UC. Early initiation of oral administration associated with azathioprine is useful in maintaining response, reducing subsequent relapses and the need for colectomy during the follow-up of these patients.

[Plasma leptin levels in patients with primary biliary cirrhosis and their relationship with degree of fibrosis]. / Concentraciones plasmáticas de leptina en los pacientes con cirrosis biliar primaria y su relación con el grado de fibrosis.

OBJECTIVES: a) To analyze plasma leptin levels in patients with primary biliary cirrhosis (PBC) and b) to investigate the relationship between leptin levels and liver fibrosis stage in a cohort of patients with PBC. PATIENTS AND METHODS: Serum leptin levels were evaluated through radioimmunoassay in 30 patients with PBC (mean age: 37.2 +/- 11.0 years; range:19-75) and in 29 controls matched for age and weight. Venous blood obtained after a 12-hour fast was centrifuged in EDTA tubes. Weight, height and body mass index (BMI) were measured using standard methods. Hepatitis C virus RNA was determined using qualitative and quantitative polymerase chain reaction. In all patients liver biopsies were performed and the degree of fibrosis and extent of inflammatory infiltrate were evaluated. RESULTS: Plasma leptin levels in patients with PBC were lower than those obtained in control subjects (p<0.0001). No significant differences were found between the two groups in age, weight, height, BMI or body fat index. There was a clear increase in serum leptin levels according to histological stage of PBC (stage I: 2.1 ng/ml; stage II: 4.3 ng/ml; stage III: 5.3 ng/ml; stage IV: 12.1 ng/ml; p<0.01) CONCLUSIONS: The present study demonstrates the correlation between leptin and stage of liver fibrosis in a cohort of patients with PBC, providing further evidence of the involvement of leptin in the process of liver fibrosis.

Involvement of the Fas system in liver allograft rejection.

OBJECTIVE: Recent studies suggest that apoptosis is an important mechanism of cell death in the rejection of liver allografts and that this process is mediated via Fas. The aim of this study was to analyze the expression of the Fas system during the liver allograft rejection and its evolution after treatment. METHODS: We evaluated 14 patients with liver allograft rejection before and after treatment. Fas immunostaining was performed by the labeled streptavidin-biotin peroxidase method using a 200-fold dilution of a monoclonal antibody. Assessment of apoptosis was determined by the terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) technique on deparaffined liver samples. Serum levels of soluble Fas antigen (sFas) were detected by an enzyme immunoassay procedure. Twelve liver transplant patients without allograft rejection were analyzed as a control group. RESULTS: The number of hepatocytes expressing Fas antigen, the percentage of apoptotic hepatocytes, and the sFas levels were higher in patients with liver allograft rejection than in controls (27.9+/-23.1% vs 1.4+/-1.2%, p < 0.001; 2.2+/-0.9% vs 1.0+/-0.1%, p = 0.02; 24.2+/-39.6 vs 2.8+/-4.0 IU/ml, p = 0.03, respectively). There was a correlation between the levels of sFas, AST (r = 0.86, p < 0.001), ALT (r = 0.78, p = 0.02), and gamma-globulin levels (r = 0.86, p < 0.001). After the rejection treatment we found a significant decrease in the Fas antigen expression (18.6+/-13.3%, p < 0.05), TUNEL index (0.2+/-0.4, p < 0.05), and levels of sFas (9.9+/-30.25 IU/ml, p = 0.005). CONCLUSIONS: 1) The demonstration of hepatocytes with Fas antigen expression and the labeling of the nuclei by the TUNEL assay suggest that apoptosis mediated by the Fas system plays a role in the pathogenesis of liver allograft rejection. 2) The Fas expression and the sFas levels decreased in patients with treatment response.

Apoptosis mediated by the Fas system in the fulminant hepatitis by hepatitis B virus.

The pathogenesis of the fulminant hepatitis B is poorly understood and both viral factors and the hosts immune response play a role. Previous studies in liver tissues of patients with chronic hepatitis B showed overexpression of Fas antigen and this was correlated with the activity of the hepatitis. The present study was done to determine the role of Fas in fulminant hepatitis B and the virological characteristics of hepatitis B infection. We studied three patients with fulminant hepatitis B. HBV-DNA was detected by dot-blot hybridization and polymerase chain reaction. The S and C gene were sequenced. Levels of serum soluble Fas antigen were detected by enzymoimmunoassays procedure. Apoptosis was determined by the TUNEL technique. Fas antigen expression was evaluated by a immunoperoxidase method. Ten healthy subjects acted as controls. The three patients showed a high expression of Fas antigen particularly among infiltrating lymphocytes; in these areas we also found many cells with in situ DNA nick labelling signals in the nuclei of most viable hepatocytes. Serum levels of soluble Fas antigen were higher in patients with fulminant hepatitis B than in controls. No specific genome mutations of hepatitis B virus were found. These data suggest that the Fas system involved in the liver injury of patients with fulminant hepatitis B.

Gene expression of tumor necrosis factor alpha and TNF-receptors, p55 and p75, in nonalcoholic steatohepatitis patients.

The main objective of this study was to analyze the pathogenic role of the tumor necrosis factor alpha (TNF-alpha) system in the development of nonalcoholic steatohepatitis (NASH). Fifty-two obese patients were studied. We investigated: (1) the expression of mRNA of TNF-alpha and their p55 and p75-receptors by quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) in hepatic and adipose tissues; and (2) the relationship between TNF-alpha, p55, and p75 and the severity of NASH. Obese patients without NASH were the control group. A remarkable increase in the expression of mRNA of TNF-alpha was found in patients with NASH in hepatic tissue (0.65 +/- 0.54) and in peripheral fat (0.43 +/- 0.45); in the control samples, the mRNA expression was 0.28 +/- 0.32, P <.007, and 0.26 +/- 0.22, P <.018, respectively. Furthermore, we found a significant increase in the mRNA levels of p55 receptor (2.42 +/- 1.81 vs. 1.56 +/- 1.17; P <.05); however, the mRNA expression of the p75 receptor was similar in both patients. Those patients with NASH with significant fibrosis presented an increase in the expression of mRNA TNF-alpha in comparison with those with a slight or nonexistent fibrosis. An overexpression of TNF-alpha mRNA is found in the liver and in the adipose tissue of NASH patients. The levels of mRNA-p55 are increased in the liver tissue of NASH patients. This overexpression is more elevated in patients with more advanced NASH. These findings suggest that the TNF-alpha system may be involved in the pathogenesis of NASH.

Dendroaspis natriuretic peptide in hepatic cirrhosis.

OBJECTIVES: Dendroaspis natriuretic peptide (DNP) is a novel peptide that is structurally similar to atrial, brain, and C-type natriuretic peptides. Many natriuretic peptides are increased in hepatic cirrhosis, but the role of DNP in cirrhosis is unknown at present. The aim of the study was to investigate plasma levels of dendroaspis natriuretic-like immunoreactivity in cirrhosis. METHODS: We measured plasma concentrations of DNP by radioimmunoassay methods in 12 cirrhotic patients without ascites and 44 cirrhotic patients with ascites, and compared these values with 20 age-matched healthy subjects. Renal function, plasma cGMP concentration, plasma renin activity, and plasma endothelin concentration were measured in each patient. RESULTS: Patients without ascites had circulating levels of DNP similar to those of healthy subjects. By contrast, patients with ascites had increased circulating DNP levels compared to both patients without ascites and healthy subjects. In addition, circulating levels of DNP increased in relation to the severity of cirrhosis. Significant positive correlations were also found between DNP levels, endothelin concentrations, and plasma renin activity. CONCLUSIONS: The results of this study indicate that plasma DNP is increased in cirrhotic patients with ascites.