Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Murine macrophages express high levels of nitric oxide synthase and produce large amounts of nitric oxide (NO) when stimulated with certain cytokines in the presence of a trace amount of lipopolysaccharide (LPS). The stimulatory cytokines include interleukin-1 (IL-1), interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha) and migration inhibitory factor. Activated macrophages are highly effective killers of intra- and extra-cellular pathogens. However, as excessive NO can lead to immunopathology (diabetes, graft-v.-host disease, EAE, liver cirrhosis, rheumatoid arthritis), NO production is necessarily under tight regulation. A number of cytokines, including IL-4, IL-10 and transforming growth factor-beta, can down regulate the induction of NO synthase in macrophages. In addition, macrophages exposed to LPS alone and then stimulated with a mix of IFN-gamma and LPS express significantly lower levels of NO synthase than cells stimulated without pre-exposure to LPS. Furthermore, NO can reduce the activity of NO synthase by feedback inhibition, and also inhibit the production of IFN-gamma by Th1 cells (thus turning off its own synthesis from upstream). The regulatory pathways involve tyrosine kinase and protein kinase C.
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PMID:The role of nitric oxide in parasitic diseases. 751 Jan

Cytokines constitute a complex network of molecules involved in the regulation of the inflammatory response and the homeostasis of organ functions. Cytokines coordinate physiologic and pathologic processes going on in the liver, such as liver growth and regeneration, inflammatory processes including viral liver disease, liver fibrosis and cirrhosis. Liver growth and regeneration are regulated by several cytokines. The platelet-derived hepatocyte growth factor, in particular, delivers a strong mitogenic stimulus for hepatocyte regeneration. The cell-mediated immune response plays a central role in hepatocellular necrosis and in the immunopathogenetic mechanisms involved in viral clearance and persistence in liver disease of viral etiology. In this context, cytokines modulate the immune system and exert direct antiviral activity by cytopathic and non-cytopathic mechanisms, as demonstrated in a transgenic mouse model. IL-6, TNF-alpha, IL-1 and IL-2 increase in acute fulminant viral hepatitis; in fact, they have pro-inflammatory and cytotoxic effects. Reduced IL-2 and IFN-alpha synthesis and increased serum levels of IL-1 and IL-2 soluble receptor (IL-2R) have been observed in HBV chronic liver disease. In HCV chronic hepatitis, IL-2R increases as well, while IFN-gamma and IL-2 decrease. In personal experimental observations, intra-hepatic messenger RNA expression of several cytokines was measured in liver specimens of patients with chronic HBV and HCV infections: patients with HCV chronic liver disease had higher levels of IL-2, IL-6, IL-10, and IFN-gamma. These data are in accordance with immunological studies showing a vigorous cell-mediated immune response in HCV chronic liver disease and a deficient immune response in HBV chronic hepatitis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Cytokine mediators in acute inflammation and chronic course of viral hepatitis]. 772 1

An imbalance between T helper cell (Th)1 and Th2-like cytokines has been described in several chronic infectious diseases. We therefore analyzed the intrahepatic messenger RNA (mRNA) expression of Th1-like (interleukin [IL]-2, interferon [IFN]-gamma) and Th2-like (IL-4, IL-10) cytokines in chronic hepatitis C patients (n = 17) and controls (n = 6) and correlated the results with liver histology and intrahepatic viral load. Intrahepatic cytokine mRNA and hepatitis C virus (HCV) RNA were quantitatively assessed by polymerase chain reaction (PCR) using a dot-blot hybridization technique. Liver biopsy specimens were histologically graded using the Scheuer Score. IFN-gamma and IL-2 mRNA expression were significantly upregulated in chronic HCV vs. controls (P < .002, P < .04, respectively). Both correlated significantly with histological fibrosis and portal tract inflammation. In contrast, the expression of IL-10 mRNA was decreased in cirrhosis and chronic HCV compared with controls (P < .02, P < .0001, respectively). IL-4 mRNA was detected inconsistently at low levels in all groups. Intrahepatic viral load did not correlate with either cytokine expression or tissue injury. In conclusion, the progressive liver injury seen in chronic HCV is associated with the upregulation of intrahepatic Th1-like cytokines and the downregulation of IL-10, a Th2-like cytokine. These results suggest a role for delayed-type hypersensitivity immune reactions in HCV related liver injury.
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PMID:Progressive liver injury in chronic hepatitis C infection correlates with increased intrahepatic expression of Th1-associated cytokines. 885 73

We previously reported that interferon-gamma (IFN-gamma) production by PBMC in response to HCV core protein was increased in patients with type C chronic liver disease. To understand better the pathophysiology of this disease, we evaluated production of IL-10 and IL-12 by PBMC from 41 patients with chronic HCV infection, including asymptomatic HCV carriers with persistently normal serum ALT values. IL-10 is known to inhibit many effector functions of the immune system, suppressing Th1-type cell development, while IL-12 stimulates differentiation of Th1-type cells, facilitating cell-mediated immunity. IL-10 production was determined by culturing lymphocytes with concanavalin A (Con A), while IL-12 was produced by monocytes in the presence of Staphylococcus aureus Cowan 1 (SAC) with or without recombinant HCV core protein, respectively. The cytokine levels in culture supernatants were measured by ELISA. Spontaneous IL-10 production was greater in patients with chronic hepatitis (CH) (229 +/- 119 pg/ml, P < 0.01) and liver cirrhosis (LC) (185 +/- 88 pg/ml, P < 0.05) than in controls (119 +/- 27 pg/ml), while it was decreased during IFN treatment (70 +/- 25 pg/ml). Both HCV core protein and Con A enhanced IL-10 production by cells from HCV-infected patients. IL-12 was not detectable in medium alone cultures, and SAC-induced IL-12 production did not differ between various patient groups and controls. Simultaneous addition of HCV protein resulted in an increase of IL-12 production in chronic liver disease compared with SAC-alone cultures. Addition of IL-10 to the cultures equally suppressed IFN-gamma production for both controls and patient groups, but the enhancing effect of IL-12 on IFN-gamma production was significantly less in LC than in controls and other patient groups. The findings suggest that secretion of IL-10/IL-12 by cells from control individuals and various patient groups may be different, and that the cytokines might show different effects on IFN-gamma production by some cells.
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PMID:Production of interleukins 10 and 12 by peripheral blood mononuclear cells (PBMC) in chronic hepatitis C virus (HCV) infection. 909 22

We previously reported that the number of TNF-alpha-producing cells was increased in the liver of patients with type C chronic liver disease. To understand further the pathophysiology of this change, we examined serum levels of two soluble TNF receptors, TNF-alphaRI (p55) and -alphaRII (p75), and IL-10, all of which act as TNF-alpha buffer, and IL-15, a novel cytokine sharing many immunological activities with IL-2, using ELISA methods. We studied control individuals and patients with type C chronic liver disease, including asymptomatic hepatitis C virus (HCV) carriers with persistently normal serum ALT values, and those with chronic hepatitis (CH), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). Both types of sTNF-alphaR closely correlated with disease progression. Patients with LC and HCC had significantly elevated levels for sTNF-alphaRII compared with the other patient groups and controls. Serum IL-10 levels were significantly greater in all chronic liver disease groups than in controls. With respect to IL-15, the values were high in CH, LC and HCC compared with those of controls. Notably, HCC patients showed highest values for both IL-10 and IL-15, with significant differences from the other patient groups. Serial determinations revealed that interferon (IFN) treatment for CH patients resulted in the suppression of circulating IL-10 and IL-15 levels along with decrease in serum aminotransferase values. Both cytokines remained at decreased levels after cessation of therapy in patients who went into clinical and virological remission. On the other hand, treatment did not affect serum levels of sTNF-alphaRs. These findings indicate that serum levels of these molecules correlated with disease progress in chronic HCV infection, and that IL-10 and IL-15 may reflect the degree of inflammation in the liver. It is also suggested that both cytokines may be related to the development of HCC.
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PMID:Serum levels of IL-10, IL-15 and soluble tumour necrosis factor-alpha (TNF-alpha) receptors in type C chronic liver disease. 932 22

Activated hepatic stellate cells (HSC) participate in matrix remodeling and deposition in liver fibrosis. The present study demonstrates that interleukin (IL)-10 is expressed by HSC upon activation in vitro or in vivo and that autocrine effects of this cytokine include inhibition of collagen production. Culture activation of HSC caused a distinct increase in IL-10 mRNA level compared with freshly isolated quiescent HSC. Treatment of cultured HSC with tumor necrosis factor-alpha, transforming growth factor-beta, or lipopolysaccharide further increased IL-10 mRNA by 2-fold and resulted in the release of IL-10 protein into the medium. HSC isolated from rats after bile duct ligation (BDL) showed prominent increases in IL-10 mRNA (x 100) and protein (x 30) levels at 7 days after BDL, but such induction disappeared in advanced liver fibrosis (19 days after BDL). IL-10 expression correlated positively with mRNA expression of interstitial collagenase and inversely with that of alpha1(I) collagen. Addition of anti-IL-10 IgG to cultured HSC caused enhanced collagen production under a basal or stimulated condition with TGF-beta, tumor necrosis factor-alpha, or lipopolysaccharide. These effects were associated with increased alpha1(I) collagen mRNA and reciprocally reduced collagenase mRNA levels. Co-transfection of HSC with an IL-10 expression vector and collagen reporter genes showed a 40% inhibition of alpha1(I) collagen promoter activity. These results demonstrate that activation of HSC causes enhanced autocrine expression of IL-10 which possesses a negative autoregulatory effect on HSC collagen production mediated at least in part by alpha1(I) collagen transcriptional inhibition and stimulation of collagenase expression. These findings, along with the demonstrated early induction of HSC IL-10 expression and its late disappearance during biliary liver fibrosis, suggest its in vivo role in matrix remodeling and a possibility that failure for HSC to sustain IL-10 expression underlies pathologic progression to liver cirrhosis.
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PMID:Expression of interleukin-10 by in vitro and in vivo activated hepatic stellate cells. 941 80

The aim of this study was to examine the immunomodulating effects of rhIL-12 on the immune response induced by hepatitis B virus (HBV) antigens in clinical subgroups of patients with HBV infection. Peripheral blood mononuclear cells (PBMC) of 80 patients were stimulated with HBsAg, HBcAg, pre-S1Ag and tetanus toxoid in the absence or presence of IL-12 (0.01, 0.1 and 1 ng/ml). Stimulation by anti-CD3+ anti-CD28 and lipopolysaccharide (LPS) were used as controls. Proliferation and cytokine production were determined by 3H-thymidine uptake and ELISA after 72 h. After stimulation with HBV antigens only, production of tumour necrosis factor-alpha (TNF-alpha) or IL-10 was observed in all patients, while interferon-gamma (IFN-gamma) was detectable in only 27 patients. After costimulation with IL-12 and HBV antigens, however, large amounts of IFN-gamma were found in all patients, while HBV-induced IL-10 production remained mostly unchanged. When clinical subgroups including patients with compensated liver cirrhosis were compared, PBMC from patients with HBeAg+ hepatitis showed the lowest capacity to produce IFN-gamma after HBV antigen-positive IL-12. These data suggest that the ability of IL-12 to enhance IFN-gamma production against HBV antigens is correlated with the presence of HBeAg and is not impaired in patients with advanced liver disease. In addition, IL-12 and IL-10 production by antigen-presenting cells may be a critical factor that determines the efficacy of the immune response against the hepatitis B virus.
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PMID:HBV-specific immune defect in chronic hepatitis B (CHB) is correlated with a dysregulation of pro- and anti-inflammatory cytokines. 1019 26

Orthotopic liver transplantation (OLT) is a successful treatment in patients with hepatitis C virus (HCV)-associated end-stage liver disease worldwide. T lymphocytes and their cytokines are believed to have a pivotal role in the defense against HCV and in allograft rejection. An immunosuppressive drug regimen may cause a cytokine imbalance toward a T helper (TH) cell type 2 profile that is associated with the persistence of infection and acceptance of the graft. The aim of this study is to assess whether cytokine imbalances toward a TH1- or TH2-type response may have a role in recurrent HCV infection and rejection after OLT. Twenty-one intrahepatic T-cell lines of 15 patients with recurrent HCV infection after OLT (group A) and 15 lines of 11 patients with rejection (group B) were studied. Both patient groups had received liver allografts because of HCV-associated end-stage liver disease. Patients with HCV-induced liver disease who did not undergo OLT served as controls: 17 patients with chronic hepatitis C (CH-C) and 8 patients with cirrhosis. At the time of liver biopsy, 14 blood-derived T-cell lines of 12 patients with recurrent HCV infection, 7 of 10 patients with rejection, and 18 of 18 control patients were also investigated. Regardless of the underlying disease (recurrent HCV infection, rejection, HCV-induced hepatitis, and cirrhosis), all liver tissue-derived T-cell lines produced interferon-gamma; some additionally produced interleukin-4 (IL-4), but none produced IL-10, indicating that the TH0/1 cytokine profile dominates. T-cell lines showing a TH1 cytokine profile derived from intrahepatic T cells could be established significantly more often in recurrent HCV infection and rejection than in controls with CH-C (Fisher's exact test, P <.05). The cytokine profile of intrahepatic T cells did not differ from that obtained in peripheral blood. TH0/1 cytokine profile dominates the intrahepatic and blood-derived immune response in recurrent HCV infection and rejection after OLT regardless of the mode of immunosuppression. The lymphokine profile of immunocompromised patients with recurrent HCV infection or rejection does not differ principally from that of patients with HCV-induced hepatitis and cirrhosis, but seems to show a TH1 profile significantly more often.
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PMID:Cytokine profile of liver- and blood-derived nonspecific T cells after liver transplantation: T helper cells type 1/0 lymphokines dominate in recurrent hepatitis C virus infection and rejection. 1071 24

The hepatitis C virus (HCV) is the leading cause of chronic liver disease worldwide. It is estimated that about 170 million people are chronically infected with HCV. Chronic hepatitis C is a major cause of cirrhosis and hepatocellular carcinoma and HCV-related end-stage liver disease is, in many countries, the first cause of liver transplantation. HCV infection is characterized by its propensity to chronicity. Because of its high genetic variability, HCV has the capability to escape the immune response of the host. HCV is not directly cytopathic and liver lesions are mainly related to immune-mediated mechanisms, which are characterized by a predominant type 1 helper cell response. Co-factors influencing the outcome of the disease including age, gender and alcohol consumption are poorly understood and other factors such as immunologic and genetic factors may play an important role. Recent studies have shown that the combination therapy with alpha interferon and ribavirin induces a sustained virological response in about 40% of patients with chronic hepatitis C. The sustained response rates are mainly dependent on the viral genotype (roughly 60% in genotype non-1 and 30% in genotype 1). Reliable diagnostic tools are now available and useful for detecting HCV infection, to quantify viral load and to determine the viral type. The assessment of the viral quasispecies and the characterization of viral sequences might be clinically relevant but standardized and simple techniques are needed. The lack of animal models and of in vitro culture systems hampers the understanding of the pathogenesis of chronic hepatitis C and the development of new antivirals. New therapeutic schedules with higher and/or daily doses of alpha interferon do not seem to improve the efficacy greatly. The conjugation with polyethylene glycol (PEG) improved the pharmacodynamics and the efficacy of alpha interferon. Emerging new therapies include inhibitors of viral enzymes (protease, helicase and polymerase), cytokines (IL-12 and IL-10), antisense oligonucleotides and ribozymes. The first candidate compounds should be available in the next few years. The development of an effective vaccine remains the most difficult and pressing challenge. Because of the high protein variability of HCV, protective vaccines could be extremely difficult to produce and therapeutic vaccines seem more realistic. Considerable progress has been made in the field of HCV since its discovery 10 years ago but a major effort needs to be made in the next decade to control HCV-related liver disease.
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PMID:Pathogenesis, diagnosis and management of hepatitis C. 1072 98

Although altered cytokine homeostasis has been implicated in the pathogenesis of both alcoholic liver and pancreas diseases, the serum cytokine pattern characteristic of concomitant alcoholic liver cirrhosis and pancreatitis has not been examined. In this paper we examine the serum levels of proinflammatory cytokines, such as IL-6, IL-8, TNF-alpha, and also antiinflammatory ones, such as IL-10 and TGF-beta, in 22 patients with alcoholic liver cirrhosis and 28 patients with chronic pancreatitis and compare them with those detected in the sera of 14 patients with concomitant alcoholic cirrhosis and pancreatitis. All patients were heavy alcohol drinkers, consuming more than 70 g of pure alcohol per day for at least 5 years. The control group consisted of 33 age- and sex-matched healthy subjects receiving an annual health examination. They were not addicted to alcohol and confirmed to be free of major cardiopulmonary, gastrointestinal and hepatobiliary-pancreatic diseases. The results indicated that the cytokine pattern in the sera of patients with concomitant liver cirrhosis and pancreatitis was characterized by increased levels of two proinflammatory cytokines: TNF-alpha, the concentration of which seemed to be influenced by both liver and pancreas injury, and IL-6, which seemed to be rather connected with pancreas injury. Increased levels of IL-8, which were detected in the sera of patients with cirrhosis, pancreatitis and concomitant cirrhosis and pancreatitis, were rather connected with exacerbation of the disease processes which occurred only in some of the patients. No significant changes in the levels of IL-10 or TGF-beta were detected in the sera of patients with chronic pancreatitis and concomitant cirrhosis and pancreatitis, while in patients with cirrhosis significantly decreased levels of IL-10 were found. A significant imbalance between proinflammatory/antiinflammatory signals was especially characteristic of alcoholic cirrhosis and concomitant cirrhosis with pancreatitis.
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PMID:Serum levels of cytokines in alcoholic liver cirrhosis and pancreatitis. 1105 48


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