transforming-growth-factor-beta and Hepatitis--Viral--Human

After hepatitis virus infection, plasma transforming growth factor (TGF)-β increases in either the acute or chronic inflammatory microenvironment. Although TGF-β is upregulated in patients with hepatocellular carcinoma, it is one of the most potent growth inhibitors for hepatocytes. This cytokine also upregulates extracellular matrix (ECM) production of hepatic stellate cells. Therefore, TGF-β is considered to be the major factor regulating liver carcinogenesis and accelerating liver fibrosis. Smad2 and Smad3 act as the intracellular mediators of TGF-β signal transduction pathway. We have generated numerous antibodies against individual phosphorylation sites in Smad2/3, and identified 3 types of phosphorylated forms (phospho-isoforms): COOH-terminally phosphorylated Smad2/3 (pSmad2C and pSmad3C), linker phosphorylated Smad2/3 (pSmad2L and pSmad3L) and dually phosphorylated Smad2/3 (pSmad2L/C and pSmad3L/C). These Smad phospho-isoforms are categorized into 3 groups: cytostatic pSmad3C signaling, mitogenic pSmad3L signaling and invasive/fibrogenic pSmad2L/C signaling. In this review, we describe differential regulation of TGF-β/Smad signaling after acute or chronic liver injuries. In addition, we consider how chronic inflammation associated with hepatitis virus infection promotes hepatic fibrosis and carcinogenesis (fibro-carcinogenesis), focusing on alteration of Smad phospho-isoform signaling. Finally, we show reversibility of Smad phospho-isoform signaling after therapy against hepatitis virus infection.

Topics: Animals; Gene Expression Regulation; Gene Expression Regulation, Neoplastic; Hepatitis, Viral, Human; Humans; Liver Diseases; Phosphorylation; Signal Transduction; Smad Proteins; Transforming Growth Factor beta

Hepatic dendritic cells (DC) unquestionably play important roles in the induction and regulation of immune responses. Due to their paucity, functional characterisation of these important antigen presenting cells has been slow but use of DC growth factors (in particular GM-CSF and Flt3L) that markedly enhance their numbers has proved helpful in furnishing adequate study material. While there is growing evidence that DC function is affected in the pathogenesis of liver disease, most work to date has been performed on non-hepatic DC. Increasing knowledge of hepatic DC biology is likely to improve our understanding of disease pathogenesis and resistance to and therapy of liver disease.

Topics: Antigens, CD; Carcinoma, Hepatocellular; Cell Count; Chemotaxis; Dendritic Cells; Hepatitis, Viral, Human; Humans; Immune Tolerance; Immunity, Cellular; Leukocytes; Liver; Liver Diseases; Liver Neoplasms; Liver Transplantation; Lymph; Lymphoid Tissue; Phagocytosis; Phenotype; Stem Cells; T-Lymphocytes; Transforming Growth Factor beta

Activation of TGFB (transforming growth factor β) promotes liver fibrosis by activating hepatic stellate cells (HSCs), but the mechanisms of TGFB activation are not clear. We investigated the role of ECM1 (extracellular matrix protein 1), which interacts with extracellular and structural proteins, in TGFB activation in mouse livers.. We performed studies with C57BL/6J mice (controls), ECM1-knockout (ECM1-KO) mice, and mice with hepatocyte-specific knockout of EMC1 (ECM1. ECM1-KO mice spontaneously developed liver fibrosis and died by 2 months of age without significant hepatocyte damage or inflammation. In liver tissues of mice, we found that ECM1 stabilized extracellular matrix-deposited TGFB in its inactive form by interacting with αv integrins to prevent activation of HSCs. In liver tissues from patients and in mice with CCl. ECM1, produced by hepatocytes, inhibits activation of TGFB and its activation of HSCs to prevent fibrogenesis in mouse liver. Strategies to increase levels of ECM1 in liver might be developed for treatment of fibrosis.

Topics: Animals; ATP Binding Cassette Transporter, Subfamily B; ATP-Binding Cassette Sub-Family B Member 4; Carbon Tetrachloride; Chemical and Drug Induced Liver Injury; Extracellular Matrix Proteins; Hepatic Stellate Cells; Hepatitis, Alcoholic; Hepatitis, Viral, Human; Humans; Liver; Liver Cirrhosis, Alcoholic; Liver Cirrhosis, Experimental; Male; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Signal Transduction; Transforming Growth Factor beta

Hepatocellular carcinoma (HCC) is one of the most aggressive cancers worldwide. In Egypt, the disease is usually detected in an advanced stage at which no treatment may be effective including surgery. Early detection of the disease is thus an important goal allowing the patient to be treated before the enlargement of the tumor or its metastasis to distant organs. Tumor markers are serological agents which serum level may be useful in predicting the presence of the tumor at early stages. Alpha fetoprotein (AFP) which is the golden marker for HCC is of low sensitivity, therefore, additional markers such as alpha-L-fucosidase (AFU), transforming growth factors alpha and beta (TGF-α and TGF-β) and interleukin-8 (IL-8) are suggested to be simultaneously evaluated in order to enhance the detection of HCC. A total of 96 patients with different liver diseases such as HCC, hepatitis C virus (HCV), hepatitis B virus (HBV) and cirrhotic patients are included in this study. Sixteen healthy volunteers are used as a control group. In patients with HCC each of AFP, AFU, TGF-α and TGF-β recorded significantly higher levels than the other patient groups and controls. HCC patients recorded significantly lower level of IL-8 compared to the other patient groups but significantly higher than the control. For AFP, AFU, TGF-α, TGF-β and IL-8, at the optimal cut-off values (obtained from the receiver operating characteristic (ROC) curves), the calculated sensitivities are 46%, 72.97%, 67.56%, 54.05% and 83.8%, respectively. The simultaneous evaluation using all of the suggested markers resulted in increasing the sensitivity up to 100%. It thus recommended that, if patients with cirrhosis, as high risk patients, are subjected to regular examination using these markers in addition to AFP, HCC may be detected by 100% sensitivity in an early stage and as a consequence an effective treatment can be achieved.

Topics: Adult; Aged; alpha-Fetoproteins; alpha-L-Fucosidase; Biomarkers, Tumor; Carcinoma, Hepatocellular; Case-Control Studies; Early Detection of Cancer; Egypt; Female; Fibrosis; Hepatitis, Viral, Human; Humans; Interleukin-8; Liver Neoplasms; Male; Middle Aged; ROC Curve; Transforming Growth Factor alpha; Transforming Growth Factor beta

Activation-induced cytidine deaminase (AID) plays a role as a genome mutator in activated B cells, and inappropriate expression of AID has been implicated in the immunopathological phenotype of human B-cell malignancies. Notably, we found that the transgenic mice overexpressing AID developed lung adenocarcinoma and hepatocellular carcinoma (HCC), suggesting that ectopic expression of AID can lead to tumorigenesis in epithelial tissues as well. To examine the involvement of AID in the development of human HCC, we analyzed the AID expression and its correlation with mutation frequencies of the p53 gene in liver tissues from 51 patients who underwent resection of primary HCCs. The specific expression, inducibility by cytokine stimulation and mutagenic activity of AID were investigated in cultured human hepatocytes. Only trace amounts of AID transcripts were detected in the normal liver; however, endogenous AID was significantly upregulated in both HCC and surrounding noncancerous liver tissues with underlying chronic hepatitis or liver cirrhosis (p < 0.05). Most liver tissues with underlying chronic inflammation with endogenous AID upregulation already contained multiple genetic changes in the p53 gene. In both hepatoma cell lines and cultured human primary hepatocytes, the expression of AID was substantially induced by TGF-beta stimulation. Aberrant activation of AID in hepatocytes resulted in accumulation of multiple genetic alterations in the p53 gene. Our findings suggest that the aberrant expression of AID is observed in human hepatocytes with several pathological settings, including chronic liver disease and HCC, which might enhance the genetic susceptibility to mutagenesis leading to hepatocarcinogenesis.

Topics: Adult; Aged; Aged, 80 and over; Amino Acid Sequence; Base Sequence; Carcinoma, Hepatocellular; Cell Line, Tumor; Cells, Cultured; Cytidine Deaminase; Enzyme Activation; Female; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Hepatitis, Viral, Human; Hepatocytes; Humans; Immunoblotting; Liver Neoplasms; Male; Middle Aged; Mutation; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transforming Growth Factor beta; Tumor Suppressor Protein p53

TGFbeta(1) has a confirmed role in liver fibrosis and its antiproliferative, proapoptotic, and immunosuppressive activities can play important roles in the pathogenesis of viral hepatitis.. The concentrations of transforming growth factor-beta(1) (TGFbeta(1)) was measured with enzyme immunoassay in the plasma of 70 patients with acute viral hepatitis types A, B, and C to evaluate an association with the course and severity of the disease.. The highest concentrations of TGFbeta(1) were observed in the first week of acute viral hepatitis types A and B (52.8+/-7.4 and 50.0+/-7.7, respectively). They were significantly higher than normal values or levels in patients with hepatitis type C. Significant correlation was observed between TGFbeta(1) concentrations and alanine aminotransferase in all groups, whereas with aspartate aminotransferase only hepatitis A and B. A four-week follow-up showed a gradual decrease in TGFbeta(1) levels in hepatitis A and B patients. In patients with acute C hepatitis, the relatively low initial TGFbeta(1) concentrations increased in the second and third weeks of follow-up. Among HBV-infected patients the highest TGFbeta(1) concentrations (75+/-17 ng/ml) were observed in the severe form of the disease.. These results support an important role of TGF-beta(1) in the pathogenesis of acute viral hepatitis that seems to be connected with the degree of hepatocyte damage, but not with its mechanism or etiology.

Topics: Acute Disease; Adult; Biomarkers; Female; Hepatitis A; Hepatitis B; Hepatitis C; Hepatitis, Viral, Human; Hepatocytes; Humans; Male; Middle Aged; Reference Values; Transforming Growth Factor beta; Transforming Growth Factor beta1

The human serine/threonine kinase hSGK1 is expressed ubiquitously with highest transcript levels in pancreas and liver. This study has been performed to determine the hSGK1 distribution in normal liver and its putative role in fibrosing liver disease. HSGK1-localization was determined by in situ hybridization, regulation of hSGK1-transcription by Northern blotting, fibronectin synthesis and hSGK1 phosphorylation by Western blotting. In normal liver hSGK1 was mainly transcribed by Kupffer cells. In liver tissue from patients with chronic viral hepatitis, hSGK1 transcript levels were excessively high in numerous activated Kupffer cells and inflammatory cells localized within fibrous septum formations. HSGK1 transcripts were also detected in activated hepatic stellate cells. Accordingly, Western blotting revealed that tissue from fibrotic liver expresses excessive hSGK1 protein as compared to normal liver. TGF-beta1 (2 ng/ml) increases hSGK1 transcription in both human U937 macro-phages and HepG2 hepatoma cells. H(2)O(2) (0.3 mM) activated hSGK1 and increased fibronectin formation in HepG2 cells overexpressing hSGK1 but not in HepG2 cells expressing the inactive mutant hSGK1(K127R). In conclusion hSGK1 is upregulated by TGF-beta1 during hepatitis and may contribute to enhanced matrix formation during fibrosing liver disease.

Topics: Blotting, Western; Carcinoma, Hepatocellular; Chronic Disease; Fibronectins; Gene Expression Regulation; Hepatitis B; Hepatitis C; Hepatitis, Viral, Human; Humans; Hydrogen Peroxide; Immediate-Early Proteins; In Situ Hybridization; Kupffer Cells; Liver; Liver Cirrhosis; Macrophages; Nuclear Proteins; Oxidants; Phosphorylation; Protein Serine-Threonine Kinases; RNA, Messenger; Transforming Growth Factor beta; Tumor Cells, Cultured; U937 Cells

Matrix metalloproteases (MMPs) and their inhibitors are effector molecules involved in extracellular matrix remodelling. The serum profile for these proteolytic enzymes and their inhibitors during acute self-limiting viral hepatitis has not been studied. We therefore determined serum concentrations of MMP-1, MMP-3, MMP-2, MMP-9 and their inhibitors (tissue inhibitors of metalloproteinase) TIMP-1, TIMP-2 and alpha2 macroglobulin (AMG) in the serum of patients during the icteric stage of self-limiting acute viral hepatitis. Transforming growth factor-beta (TGF-beta) and interleukin (IL)-10, two cytokines involved in the regulation of MMPs and TIMPs were also assessed. Nineteen patients (12 men, seven women) with a mean age of 29.9 years (range 16-65 years) participated in the study. Fifteen had hepatitis B virus (HBV, two HCV and two HAV infection. The values of patients were compared with those obtained from 15 blood donor controls (eight men, seven women), mean age 36.2 years (range 18-55 years). Serum levels of TGF-beta, IL-10, MMP-1, MMP-3, MMP-2, MMP-9, TIMP-1 and TIMP-2 were assessed by ELISA. MMP-2 and MMP-9 were also measured by a zymogram protease assay. alpha2 macroglobulin (AMG) was measured by nephelometry. Compared with the healthy controls the mean serum concentrations of all MMPs were significantly decreased in the acute hepatitis patients. There was no difference in the serum concentration of TIMP-1 between patients and the controls. Serum levels of TIMP-2 (P < 0001), TGF-beta (P < 0.05), IL-10 (P < 0.001) and AMG (P < 0001) were increased in patients compared to healthy controls. A statistically significant negative correlation by linear regression analysis was found between AMG and MMP-1 (P=0003). The decreased levels of MMPs observed, together with normal and increased levels of TIMP-1 and TIMP-2, may indicate an attempt to limit matrix degradation at this stage of disease resolution. The increased levels of the anti-inflammatory cytokines IL-10 and TGF-beta might be the underlying mechanism responsible for the above effect. AMG inhibition especially for MMP-1 may play an additional important role.

Topics: Acute Disease; Adolescent; Adult; Aged; alpha-Macroglobulins; Female; Hepatitis, Viral, Human; Humans; Interleukin-10; Male; Matrix Metalloproteinase Inhibitors; Matrix Metalloproteinases; Middle Aged; Tissue Inhibitor of Metalloproteinase-1; Tissue Inhibitor of Metalloproteinase-2; Transforming Growth Factor beta

To investigate the relationship between expression of transforming growth factor beta 1(TGF beta 1), TGF beta 1 mRNA in liver tissue of patients with chronic viral hepatitis and degree of liver fibrosis.. TGF beta 1 protein was detected in 45 patients by immunohistochemistry and TGF beta 1 mRNA was detected in 21 of the 45 cases by in situ hybridization.. TGF beta 1 protein was 88.89%(40 of 45) positive in their liver tissues and was mainly distributed in interstitial cells, portal areas and the areas where fibrosis actively occurred, and the expression of TGF beta 1 protein was positively correlated with degree of liver fibrosis(r = 0.73, P < 0.05). TGF beta 1 mRNA was 80.95%(19 of 21)positive in their liver tissues. Positive stains were not only detected in sinusoidal cells and mononuclear cells, but also in some parenchymal cells.. The expression of TGF beta 1 correlated closely with liver fibrosis of viral hepatitis. Not only interstitial cells, but also parenchymal cells in liver might participate in the fibrogenisis by producing TGF beta 1.

Topics: Adolescent; Adult; Aged; Female; Hepatitis, Chronic; Hepatitis, Viral, Human; Humans; Male; Middle Aged; RNA, Messenger; Transforming Growth Factor beta

33 specimens of liver biopsy from patients with different types of viral hepatitis were detected for transforming growth factor-beta 3(TGF-beta 3) by immunohistochemistry. The results showed that TGF-beta 3 mainly distributed in the sinusal walls cells in sinus portal, areas fibrous, septum, hepatocytes in pseudolobes and necrotic areas of severe hepatitis. The expressing intensity of TGF-beta 3, was stronger in the cirrhosis, chronic severe hepatitis than that in the chronic and acute hepatitis. As the expression of TGF-beta 3 increased, the level of serum bilirubin ascended and plasmozyme activity was prolonged. It may be concluded that the expression of TGF-beta 3 is correlated with severe hepatitis and the progress of the liver cirrhosis.

Topics: Adolescent; Adult; Female; Hepatitis B, Chronic; Hepatitis, Viral, Human; Humans; Liver; Liver Cirrhosis; Male; Middle Aged; Prognosis; Transforming Growth Factor beta; Transforming Growth Factor beta3

We examined the relationships among vitronectin (VN), plasminogen activator inhibitor-1 (PAI-1), and transforming growth factor beta 1 (TGF-beta 1) in liver diseases to evaluate the presence of plasmin cascade in human hepatic fibrosis.. Blood and liver tissues were obtained from 57 patients with liver disease. Plasma VN, PAI-1 antigen, and PAI-1 activity levels were evaluated. Biopsied liver specimens were observed by light and electron microscopy after immunohistochemical staining. Morphometric analysis was performed on these specimens.. Plasma VN and PAI-1 activity levels decreased significantly with the progression of hepatic fibrosis and were particularly marked in the liver cirrhosis group. Plasma PAI-1 antigen level increased significantly. The immunolocalization of the active form of TGF-beta became more intense with the progression of hepatic fibrosis, whereas that of the dual-stained positive areas of PAI-1 and VN (PAI-1.VN) decreased. There was a positive correlation between TGF-beta and PAI-1, whereas there was a negative correlation between TGF-beta and PAI-1.VN. Immunoelectron microscopy showed the localization of PAI-1-VN in the extracellular space around the sinusoidal cells or surface of aggregating platelets, TGF-beta mainly in Ito cells, and VN in hepatocytes near the focal necrotic area or fibrous septa.. These findings suggest that VN and PAI-1 are related to the active form of TGF-beta and that it is possible that the plasmin cascade is present in the human liver.

Topics: Adult; Female; Fibrinolysin; Hepatitis, Viral, Human; Humans; Liver; Liver Cirrhosis; Male; Microscopy, Immunoelectron; Middle Aged; Plasminogen Activator Inhibitor 1; Serine Proteinase Inhibitors; Transforming Growth Factor beta; Vitronectin

Transforming growth factor-beta1 is an important cytokine involved in cell growth and inflammation which has been shown to be inhibitory to hepatic DNA synthesis. The aim of this study was to investigate the plasma levels and hepatic mRNA expression of transforming growth factor-beta1 in patients with fulminant hepatic failure in whom liver regeneration may be impaired.. Plasma levels of transforming growth factor-beta1 and human hepatocyte growth factor were measured in 57 fulminant hepatic failure patients and 20 healthy volunteers by ELISA. Northern blot analysis of transforming growth factor-beta1 and H3 histone, a marker for liver proliferation, was performed in liver tissue of 14 fulminant hepatic failure patients.. The plasma levels of total transforming growth factor-beta1 in fulminant hepatic failure patients on admission (median 38.8 ng/ml, range 8.4-108 ng/ml) were significantly higher than those in control subjects (23.0 ng/ml, 8.5-34.9 ng/ml, p<0.001). Significantly higher levels were observed in non-A, non-B hepatitis patients (57.9 ng/ml, 38.8-108 ng/ml, n=10, p<0.001) compared to patients with paracetamol overdose (37.1 ng/ml, 8.4-72.5 ng/ml, n=47). In contrast, the plasma levels of free transforming growth factor beta1 were greater in paracetamol overdose (623 pg/ml, 46.7-1241 pg/ml, n=21) than in non-A, non-B hepatitis (131 pg/ml, 77.2-254 pg/ml, n=9), with both being higher than control (72.3 pg/ml, 28.7-108, n=7, p<0.001). The plasma levels of human hepatocyte growth factor in patients with paracetamol overdose (7.04 ng/ml, 1.00-62.4 ng/ml) were significantly higher than those in patients with non-A, non-B hepatitis (4.48 ng/ml, 0.74-9.10 ng/ml, p<0.05). Northern blots showed increased mRNA expression of transforming growth factor-beta1 in paracetamol-overdose patients (n=8, p<0.05), but not in patients with non-A non-B hepatitis (n=6), compared to controls (n=4).. The increased circulating plasma TGF-beta1 in FHF may be part of the tissue repair process in fulminant hepatic failure. In patients with non-A, non-B hepatitis, the increased total transforming growth factor-beta1 together with a less elevated hepatocyte growth factor could be related to impaired liver regeneration in this group.

Topics: Acetaminophen; Adolescent; Adult; Aged; Analgesics, Non-Narcotic; Blotting, Northern; Enzyme-Linked Immunosorbent Assay; Female; Hepatic Encephalopathy; Hepatitis, Viral, Human; Hepatocyte Growth Factor; Histones; Humans; Liver; Liver Transplantation; Male; Middle Aged; RNA, Messenger; Transforming Growth Factor beta