Telomerase is highly activated in human immortal cell lines and tumor tissues, whereas it is not activated in primary cell strains and many tumor-adjacent tissues. It is suggested that telomerase activation is one of the critical steps in malignant transformation. In the present study, the telomerase activity was investigated in hepatocellular carcinoma tissues and non-tumor liver tissues from Korean patients with chronic hepatitis and cirrhosis. Eighty two liver tissues (24 chronic hepatitis specimens, 34 cirrhosis specimens, and 24 hepatocellular carcinomas) were obtained from 23 chronic viral hepatitis patients, 19 cirrhosis patients (including 7 liver transplants), and 24 patients with hepatocellular carcinoma, of which the surrounding non-tumor liver tissues were available in 16 patients (1 chronic hepatitis and 15 cirrhosis). As negative controls, 3 normal liver tissues were included. Protein from liver specimens was purified by a detergent lysis method as described elsewhere, and telomerase activity was measured in 2 diluents of each sample (1:1 and 1:100) by a telomeric repeat amplification protocol (TRAP). Telomerase was strongly activated in 79% (19/24) of the hepatocellular carcinomas, while weakly in 8% (2/24) of the chronic hepatitis tissues and in 24% (8/34) of the cirrhosis tissues. All of 3 normal control livers showed no telomerase activation. No relationship could be observed between the enhancement of telomerase activity and tumor nature. None of the chronic heaptitis or cirrhosis patients with mild telomerase activation in the liver have developed hepatocellular carcinoma for at least 2 years of follow-up period. These results suggest that the strong enhancement of telomerase activity may be a critical part of hepatocarcinogenesis, although the exact mechanism of such high activation in hepatocellular carcinoma is not clear. In addition, further study will be necessary to clarify the reason why no telomerase activity detectable by a conventional TRAP can be seen in some hepatocellular carcinoma.
Adult ; Aged ; Carcinoma, Hepatocellular/pathology ; Carcinoma, Hepatocellular/enzymology* ; Cell Transformation, Neoplastic* ; Comparative Study ; Enzyme Activation ; Female ; Hepatitis, Chronic/enzymology ; Human ; Liver Cirrhosis/enzymology ; Liver Neoplasms/pathology ; Liver Neoplasms/enzymology* ; Male ; Middle Age ; Precancerous Conditions/enzymology* ; Telomerase/analysis*

Animals ; Immunohistochemistry ; In Situ Hybridization ; Liver ; enzymology ; pathology ; Liver Cirrhosis ; enzymology ; etiology ; pathology ; Male ; Matrix Metalloproteinase 2 ; analysis ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Wistar

BACKGROUND/AIMS: An ideal noninvasive diagnostic test for hepatic fibrosis should be simple, inexpensive, and accurate. We aimed to find the simple marker for predicting hepatic fibrosis and to compare the accuracy of AST, platelet, AST/ALT ratio and AST to platelet ratio index (APRI) in chronic hepatitis B patients without clinical evidence of cirrhosis. METHODS: A total of one hundred and twenty-six chronic hepatitis B patients who underwent liver biopsy at the Ajou University Hospital from August 1998 to December 2003 were enrolled. Hepatic fibrosis was assessed using the Ludwig classification. Significant fibrosis was defined as fibrosis score of 3 or more. The AST/ALT ratio and APRI were calculated and correlations with hepatic fibrosis were analyzed. RESULTS: APRI showed a significant correlation (r=0.501, p=0.000) with hepatic fibrosis, and was superior to AST, AST/ALT ratio and platelet in predicting fibrosis. Patients with significant fibrosis (fibrosis stage 3, 4) can be identified to have APRI=1 with sensitivity 71.2% and specificity 70.3%. The sensitivity and specificity of an APRI = 1.5 for cirrhosis (stage 4) were 83.3% and 75.0%. CONCLUSIONS: Simple index using AST and platelet value can predict the presence of significant fibrosis and cirrhosis in chronic hepatitis B patients without clinical evidence of cirrhosis.
Adult ; Alanine Transaminase/blood ; Aspartate Aminotransferases/*blood ; Female ; Hepatitis B, Chronic/blood/enzymology/*pathology ; Humans ; Liver/pathology ; Liver Cirrhosis/*pathology/virology ; Male ; *Platelet Count ; Sensitivity and Specificity

OBJECTIVETo investigate the relevant factors of liver histological changes in chronic hepatitis B (CHB) patients with mildly elevated ALT and to explore the clinical values of these factors on anti-viral treatment.

METHODSA total of 152 CHB patients with mildly elevated ALT (less than 2 x ULN) who underwent liver biopsy were included in the study. Correlations between routine laboratory markers, liver histological inflammation grade and fibrosis stage were statistically assessed by Spearman correlation analysis, one-way ANOVA, area under the curve (AUC) of the receiver operating characteristic curves (ROC) and Logistic regression statistical analysis.

RESULTSAll patients in the study showed various hepatic histological damages. Among the 152 patients 50 (32.9%) were found with inflammation grade 1 (G1), 42 (27.6%) with G2, 46 (30.3%) with G3 and 14 (9.2%) with G4. 16 patients (10.5%) were found with fibrosis stage 2 (S2), 25 (16.5%) with S3 and 41 (27.0%) with S4. Routine laboratory markers Alb, BPC and WBC were significantly correlated with hepatic histological inflammation grade and fibrosis stage. Marked liver fibrosis and moderate to severe liver damage were significantly higher in patients aged more than 40 years as compared to those less than 40 years of age (P = 0.002, P = 0.010). The regression equation P = 1/[1+e-(9.36250-1625Alb-0.0234BPC)] was established with sensitivity and specificity of 83.3% and 65.0%, respectively.

CONCLUSION67.8% of CHB patients with mildly elevated ALT have significant injury to the liver tissue. CHB patients aged more than 40 years have a significant increase of marked liver fibrosis and moderate to severe liver damage. The regression equation is valuable to predict whether CHB patients need antiviral therapy or not.

Adolescent ; Adult ; Alanine Transaminase ; metabolism ; Female ; Hepatitis B, Chronic ; enzymology ; metabolism ; pathology ; Humans ; Liver ; pathology ; Liver Cirrhosis ; pathology ; Male ; Middle Aged ; Young Adult

OBJECTIVETo investigate the mechanism of salvianolic acid B (Sal B) action against liver fibrosis through preventing lipid peroxidation and regulating MMP-2 activity in liver.

METHODThe liver fibrotic model was induced through intraperitoneally injection of DMN at a dose of 10 microg x kg(-1) for every other day and lasting for 4 weeks. Sal B was administered (10 mg x kg(-1)), and perindopril (5 mg x kg(-1)) was used as positive control. Hepatic inflammation and collagen were observed with HE and sirius red staining. The liver function including serum ALT, AST activity, Alb and total bilirubin (T. Bil) level were determined. The hepatic lipid peroxidation including SOD and GST activities and GSH content were measured. Hepatic hydroxyproline (Hyp) content was detected with Jamall's method. The activity of metalloproteinase was assayed by gelatin zymography. The expressions of alpha-SMA, Col I in liver tissue were analyzed by Western blot.

RESULTThe model rats had higher serum T. Bil content, ALT and AST activities but lower Alb content than the normal rats, also had remarkable inflammatory necrosis and collagen deposition in liver, with much higher Hyp content, protein expression of alpha-SMA and collagen I and MMP-2 activity in liver, but had a decreased GSH content, SOD and GST activities. Both Sal B and perindopril attenuated hepatic injury and collagen deposition in model rats, decreased serum ALT activity and hepatic Hyp content, down-regulated alpha-SMA and collagen I protein expressions and metalloproteinase-2 activity than those in the model group, but increased SOD activity and GSH content, and Sal B decreased serum T. Bil content and increased GST activity. Sal B had a much better comprehensive actions than perindopril.

CONCLUSIONSal B has a good preventive action against liver fibrosis, the action mechanism is related to the prevention from lipid peroxidation and down-regulation of metalloproteinase-2 activity in fibrotic liver.

Animals ; Benzofurans ; therapeutic use ; Lipid Peroxidation ; drug effects ; Liver ; drug effects ; enzymology ; metabolism ; pathology ; Liver Cirrhosis ; drug therapy ; enzymology ; metabolism ; pathology ; Male ; Matrix Metalloproteinase 2 ; metabolism ; Rats ; Rats, Sprague-Dawley

NADPH oxidase (NOX) is a multicomponent enzyme complex that generates reactive oxygen species (ROS) in response to a wide range of stimuli. ROS is involved as key secondary messengers in numerous signaling pathways, and NADPH oxidases complex has been increasingly recognized as key elements of intracellular signaling of hepatic fibrogenesis. In the liver, NADPH oxidase is functionally expressed both in the phagocytic form and in the non-phagocytic form. The non-phagocytic NADPH oxidase complex is structurally and functionally similar to the phagocytic NADPH, resulting in reduction of molecular oxygen to generate superoxide. There are six homologous NOX proteins in the non-phagocytic forms of NADPH oxidase. An emerging concept is that both phagocytic and nonphagocytic NADPH oxidase components in hepatic stellate cells (HSCs) mediate hepatic fibrosis, suggesting its potential role as a pharmacological target for anti-fibrotic therapy. The molecular components and signaling pathways of various NADPH oxidase homologues that are critical for the fibrotic activity in HSCs need to be more clearly identified.
Angiotensin II/metabolism ; Hepatic Stellate Cells/metabolism ; Humans ; Liver Cirrhosis/*enzymology/pathology ; NADPH Oxidase/*metabolism ; Oxidative Stress ; Reactive Oxygen Species/metabolism

OBJECTIVETo investigate the expression dynamics and significance of matrix metalloproteinase-2 (MMP-2) membrane type-matrix metalloproteinase-2 (MT-MMP-2) in hepatic fibrosis and its reversal counterpart.

METHODSAn experimental CCl4 induced hepatic fibrosis rat model was established by intraperitoneal administration of carbon tetrachloride for 2, 4, 6, 8, 10 weeks, and normal rats were used as a control group. The immunohistochemical methods and in situ hybridization were used to detect MMP-2,MT-MMP-2 mRNA and related antigens in the liver.

RESULTSMMP-2,MT-MMP-2 mRNA and related antigens were expressed in mesenchymal cells and parts of hepatocytes besides active pathological changes, especially in the fibrous septum and portal area. Expression of MMP-2,MT-MMP-2 mRNA and related antigens were increased in hepatic fibrosis and decreased gradually in its reversal counterpart.

CONCLUSIONThis study suggested that mesenchymal cells are the main cellular origins of MMPs. The levels of MMP-2 and MT-MMP-2 antigens and gene expression were closely related to hepatic fibrosis. MMP-2 and MT-MMP-2 may play important roles in hepatic fibrosis and its reversal counterpart.

Animals ; Carbon Tetrachloride Poisoning ; Gene Expression Regulation, Enzymologic ; Hepatocytes ; enzymology ; Liver ; enzymology ; pathology ; Liver Cirrhosis, Experimental ; enzymology ; etiology ; pathology ; Male ; Matrix Metalloproteinase 2 ; biosynthesis ; genetics ; Matrix Metalloproteinases ; biosynthesis ; genetics ; Matrix Metalloproteinases, Membrane-Associated ; Mesenchymal Stromal Cells ; enzymology ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Wistar

OBJECTIVETo investigate the underlying molecular mechanism of the cholesterol-blocking drug, simvastatin, in treating nonalcoholic fatty liver fibrosis.

METHODA rat model of nonalcoholic fatty liver fibrosis was established by feeding Wistar rats a fat-rich diet. After treatment with simvastatin (4 mg/kg/day), liver histological specimens were stained with hematoxylin-eosin and Masson's trichrome for microscopic analysis. Expression of adenosine monophosphate-activated protein kinase-alpha (AMPKa) was evaluated by reverse transcription-polymerase chain reaction (RT-PCR; for mRNA) and Western blotting (protein). The levels of serum total cholesterol (TC), triglycerides (TG), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and tumor necrosis factor-alpha (TNFa) were measured by standard biochemical assays. The human hepatic stellate cell line, LX-2 (quiescent or activated), was treated with transforming growth factor-beta 1 (TGF-b1) alone, simvastatin alone, or TGF-b1 + simvastatin. RT-PCR and Western blotting were used to determine changes in AMPKa mRNA and protein expression, respectively.

RESULTSIn the rat model of nonalcoholic fatty liver fibrosis, the extent of pathological changes in hepatic tissues correlated with severity of disease progression. The levels of serum TC, TG, ALT, AST and TNFa were increased significantly in model rats (vs. healthy controls; all, P less than 0.01). AMPKa mRNA expression and activity was significantly decreased in model rats (vs. healthy controls; P less than 0.01 and P less than 0.05, respectively). Simvastatin, treatment significantly improved all of these parameters in model rats (vs. untreated model rats; all, P less than 0.05). In vitro simvastatin treatment of human HSCs significantly increased AMPKa activity (quiescent LX-2: 0.93+/-0.10 vs. 0.72+/-0.09, activated LX-2: 0.72+/-0.10 vs. 0.54+/-0.10, q=7.00, 6.00; all, P less than 0.01), decreased a-smooth muscle actin expression (mRNA: 0.30+/-0.02 vs. 0.36+/-0.02, protein: 0.30+/-0.03 vs. 0.38+/-0.02, q=11.245, 11.216; all, P less than 0.01), and decreased collagen I expression (mRNA: 0.30+/-0.03 vs. 0.37+/-0.03, protein: 0.25+/-0.03 vs. 0.33+/-0.03, q=8.791, 11.163; all, P less than 0.01).

CONCLUSIONSimvastatin may improve nonalcoholic fatty liver fibrosis by inducing AMPK phosphorylation.

Adenylate Kinase ; metabolism ; Animals ; Cell Line ; Fatty Liver ; drug therapy ; metabolism ; pathology ; Hepatic Stellate Cells ; drug effects ; enzymology ; Humans ; Liver Cirrhosis ; metabolism ; pathology ; Male ; Rats ; Rats, Wistar ; Simvastatin ; pharmacology ; therapeutic use

Adolescent ; Adult ; Aged ; Ascites ; enzymology ; Ascitic Fluid ; enzymology ; pathology ; Diagnosis, Differential ; Female ; Glucuronidase ; biosynthesis ; genetics ; Humans ; Liver Cirrhosis ; diagnosis ; Male ; Middle Aged ; Peritoneal Neoplasms ; diagnosis ; secondary ; RNA, Messenger ; biosynthesis ; genetics

OBJECTIVETo investigate the molecular mechanisms of diaphragm injury in rats with liver cirrhosis.

METHODSThirty adult male Sprague-Dawley rats were randomized into control group (n=10) and carbon tetrachloride-induced liver cirrhosis group (LC group, n=20). In the 9th week, the rat body weight and diaphragm to body weight ratio were measured, and the parameters of diaphragm contractility including peak twitch tension (Pt), maximum tetanic tension (Po), time to peak contraction (CT), half relaxation time (1/2RT), and force-frequency curve were assessed using a Medlab-U/4C biological signal collecting system. The activities of superoxide dismutase (SOD), succinic dehydrogenase (SDH) and myeloperoxidase (MPO) and malondiadehyde (MDA) content in the diaphragm were detected. The mRNA expression levels of sarcoplasmic reticulum calcium ATPase (SERCA) and cytoskeletal proteins (titin and nebulin) in the diaphragm were detected by RT-PCR, and the diaphragm ultrastructure was examined with electron microscopy.

RESULTSCompared with those in the control group, body weight, diaphragm to body weight ratio, Pt, Po, and tetanic force under the stimulus frequency of 10, 20, 40, 60, 100 Hz were all significantly decreased (P<0.01), while CT and 1/2RT were significantly prolonged in LC group (P<0.01). SOD and SDH activities were significantly lowered (P<0.01) while the contents of MDA and MPO activity were significantly increased in LC group (P<0.01) with significantly decreased SERCA, titin and nebulin mRNA expressions in the diaphragm (P<0.01). Electron microscopy of the diaphragm in LC group revealed myofibrillar degeneration, absence of the Z line, and mitochondria swelling and edema.

CONCLUSIONLiver cirrhosis increases free radicals and aggravates inflammatory response and lipid peroxidation in the diaphragm, thus leading to mitochondrial damages and decreased expressions of cytoskeletal proteins and SERCA to cause diaphragmatic dysfunction.

Animals ; Body Weight ; Carbon Tetrachloride ; Connectin ; metabolism ; Diaphragm ; metabolism ; Lipid Peroxidation ; Liver ; enzymology ; pathology ; Liver Cirrhosis ; metabolism ; Male ; Muscle Contraction ; Muscle Proteins ; metabolism ; Oxidation-Reduction ; Rats ; Rats, Sprague-Dawley ; Sarcoplasmic Reticulum Calcium-Transporting ATPases ; metabolism