OBJECTIVETo study the proliferation and apoptosis in carbon tetrachloride induced rat liver fibrosis.

METHODSWistar rats were injected subcutaneously with 40% CCl4-olive oil twice weekly for 12 weeks. Liver tissues were obtained at the end of 4, 8, 12 and 16 weeks for histological examination, hydroxyproline (Hyp) assay and proteomic analysis. After two dimension electrophoresis (2-DE), the silver stained gels were analyzed with PDQUEST 2-DE. More than 30 differentially expressed proteins were identified by MALDI-TOF-MS.

RESULTSThe degree of collagen deposition and hydroxyproline content of the fibrotic livers increased continuously during the 12 weeks of CCl4 administration, peaked at the end of week 12 (P < 0.05) and declined significantly at week 16 (P < 0.05). Significant differences were observed in two parameters at each time point between the control and the model group. Meanwhile, dramatic change of hepatic proteome in the model group rats was also seen. Differentially expressed proteins identified by MALDI-TOF-MS were categorized as proliferation-related proteins/enzymes (proliferating cell nuclear antigen p120, p40 and cyclin F ubiquitin-conjugating enzyme 7 UBC7), and apoptosis-related proteins, mainly caspase-12 which was absent in the control rats.

CONCLUSIONProliferation and apoptosis related proteins are expressed dynamically in different stages of rat liver fibrosis induced by CCl4.

Animals ; Apoptosis ; Carbon Tetrachloride ; Carbon Tetrachloride Poisoning ; Caspase 12 ; metabolism ; Cell Proliferation ; Hydroxyproline ; metabolism ; Liver Cirrhosis, Experimental ; chemically induced ; metabolism ; Male ; Proteins ; metabolism ; Proteome ; metabolism ; Rats ; Rats, Wistar

OBJECTIVETo investigate the dynamic changes of the hepatic proteome during the formation and resolution of rat liver fibrosis induced by carbon tetrachloride and the effect of Fuzheng Huayu Decoction on it.

METHODSLiver fibrosis in Wistar rats was induced by subcutaneous injection of 40% CCl4 in olive oil while the rats in the treatment group received Fuzheng Huayu Decoction. Pathological examination, hydroxyproline content determination and protein extraction of the rats livers were performed at four time points, i.e. at the end of 4, 8, 12 and 16 weeks. After 2-dimensional electrophoresis (2-DE), the gels were analyzed using the PDQUEST 2-DE image analysis software and differentially expressed proteins were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS).

RESULTS(1) The 2-DE examination showed that the model group-specific proteins and differentially expressed proteins presented started at 4 weeks and reached their peaks at 12 weeks, and this was conformed by MALD-TOF-MS identification. (2) In addition, 18 proteins were present at all time points and another 19 proteins were absent in the model group among those identified by MALD-TOF-MS. (3) Fuzheng Huayu Decoction down-regulated proteins and their expressions increased at 4 and 8 weeks, whereas it up-regulated those which decreased at 8, 12 and 16 weeks.

CONCLUSIONS(1) The changes in protein expressions, which effect metabolism, neuroendocrine function and cell proliferation, are the basis of liver fibrosis. (2) The anti-fibrotic effect of Fuzheng Huayu Decoction is holistic, specifically because it can decrease the abnormal cell proliferation and can increase the synthesis of normal proteins.

Animals ; Carbon Tetrachloride ; Carbon Tetrachloride Poisoning ; Drugs, Chinese Herbal ; therapeutic use ; Liver ; metabolism ; Liver Cirrhosis, Experimental ; drug therapy ; metabolism ; Male ; Phytotherapy ; Proteome ; metabolism ; Rats ; Rats, Wistar

Landfill is one of the important sources of carbon tetrachloride (CT) pollution, and it is important to understand the degradation mechanism of CT in landfill cover for better control. In this study, a simulated landfill cover system was set up, and the biotransformation mechanism of CT and the associated micro-ecology were investigated. The results showed that three stable functional zones along the depth, i.e., aerobic zone (0-15 cm), anoxic zone (15-45 cm) and anaerobic zone (> 45 cm), were generated because of long-term biological oxidation in landfill cover. There were significant differences in redox condition and microbial community structure in each zone, which provided microbial resources and favorable conditions for CT degradation. The results of biodegradation indicated that dechlorination of CT produced chloroform (CF), dichloromethane (DCM) and Cl^- in anaerobic and anoxic zones. The highest concentration of dechlorination products occurred at 30 cm, which were degraded rapidly in aerobic zone. In addition, CT degradation rate was 13.2-103.6 μg/(m²·d), which decreased with the increase of landfill gas flux. The analysis of diversity sequencing revealed that Mesorhizobium, Thiobacillus and Intrasporangium were potential CT-degraders in aerobic, anaerobic and anoxic zone, respectively. Moreover, six species of dechlorination bacteria and eighteen species of methanotrophs were also responsible for anaerobic transformation of CT and aerobic degradation of CF and DCM, respectively. Interestingly, anaerobic dechlorination and aerobic transformation occurred simultaneously in the anoxic zone in landfill cover. Furthermore, analysis of degradation mechanism suggested that generation of stable anaerobic-anoxic-aerobic zone by regulation was very important for the harmless removal of full halogenated hydrocarbon in vadose zone, and the increase of anoxic zone scale enhanced their removal. These results provide theoretical guidance for the removal of chlorinated pollutants in landfills.
Bacteria/metabolism* ; Biodegradation, Environmental ; Carbon Tetrachloride/metabolism* ; Methane/metabolism* ; Waste Disposal Facilities

OBJECTIVE: To investigate the effect of prostaglandin E1 (PGE1) on the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) in experimental liver fibrosis rats. METHODS: The liver fibrosis model was established by carbon tetrachloride. Rats were divided into a control group and PGE1-treated group. The pathological changes of the liver tissue from the two groups, the semi-quantitative analysis of hepatitic activity in HE stain sections, the pathological image quantitative analysis of the fibrosis degree, TIMP-1 positive cells, and the content of collagen were synthetically analysed. RESULTS: The mark changes of liver pathology in HE stain sections were that the degree of hepatitic activity in the PGE1-treated group was obviously lower than that in the control group (P < 0.05). The fibrosis degree, TIMP-1 positive cells and the collagenous fibers decreased in the PGE1-treated group (P <0.05). CONCLUSION PGE1 has an anti-hepatofibrosis effect in the experimental rats, the inflammation of liver is light, and the proliferation of collagenous fibers can be restrained, whose mechanism is probably associated with the suppression of TIMP-1 expression caused by PGE1.
Alprostadil ; pharmacology ; Animals ; Carbon Tetrachloride ; Carbon Tetrachloride Poisoning ; Female ; Liver Cirrhosis, Experimental ; chemically induced ; metabolism ; Male ; Random Allocation ; Rats ; Rats, Wistar ; Tissue Inhibitor of Metalloproteinase-1 ; biosynthesis ; genetics

The simultaneous administration of two or more drugs may result in interactions that increase or decrease the intended effects of one or both drugs. These interactions are often the result of induced alterations in the metabolism of the drugs. A wide variety of unrelated chemical agents are also capable of enhancing the activity of drug-metabolizing enzymea in the smooth-surfaced endoplasmic reticulum of the liver, and this accelerated metabolism alters the duration and intensity of action of a variety of pharmacological agents. Phenobarbital is a well known drug which promotes the metabolism of durgs in the liver. Some volatile or intravenous anesthetics were reported that enhance hepatic microspmal metabolism for themselves or for other drugs. Of these, Chang and Glazko (1974) reported that ketamine pretreatment did not influence the demethylation rate of drug metabolism and the liver weight in rats. However many opposite opinions have been expressed that ketamine enhanced mierosomal drug metabolism. Marietta et al (1975 and 1976) reported that the demethylating enzyme fraction of the ketamine-pretreated group was double of that of the control group in vitro. Thus we have made a study to evaluate the enhancement of drug metabolism induced by ketamine hydrochloride. Our experimental mice were divided into 4 groups, preteated with saline, phenobarbital, ketamine or carbon tetracbloride for 3 days. On the 1 st, 3 rd, 5th, 7th and 14th day after the pretreatment, we selected 10 mice randomly in each group, and hexobarbital(100mg/kg) was administered intraperitonealy. Then we evaluated the sleeping time, liver weight and microscopic findings of liver tissue. The results are as follows: 1) On the 1 st, 3 rd and 5th day after the pretreatment, the duration of hexobarbital induced hypnosis was significantly shorter in the ketamine-pretreated group than that in the control group, but not as long as that in the phenobarbital-pretreated group. 2) There was no remarkable change of the liver weight in the ketamine pretreated group. On the 1st and 3rd day after the pretreatment, liver weight was significanty increased in the phenobarbital and carbon tetrachloride pretreated groups. 3). Microscopic findings of liver showed no remarkable change in the ketamine-pretreated group, but there were significant cholestasis and hydrophic degeneration in the phenobarbital-and carbon tetrachloride-pretreated group respectively. In conclusion, it may be indicated that ketamine enhances hepatic microsomal drug metabolism because of shortening of the duration of hexobarbital-induced hypnosis.
Anesthetics, Intravenous ; Animals ; Carbon ; Carbon Tetrachloride ; Cholestasis ; Endoplasmic Reticulum ; Hexobarbital ; Hypnosis* ; In Vitro Techniques ; Ketamine ; Liver ; Metabolism ; Mice ; Phenobarbital ; Rats

OBJECTIVETo investigate the expression of PDGF receptor-beta and its correlation with extracellular matrix in hepatic tissue during hepatic fibrosis.

METHODSThe model of hepatic fibrosis in rats was induced by carbon tetrachloride. PDGF receptor-beta subunit, collagen I, collagen III and a-SMA in hepatic tissues of these rats were examined using immunohistochemistry. The correlation between PDGF receptor-beta subunit and collagen I, III was analyzed using SAS software after the results of immunohistochemistry were semi-quantified.

RESULTSPDGF receptor-beta subunit and a-SMA were not detected in normal controls. Collagen I and III were distributed in the portal tracts and beneath the endothelia of the central veins and of the Disse spaces. Two weeks after CCl4 injection, the PDGF receptor-beta and a-SMA were detected, and the expression of collagen I and III increased. At the end of 4 and 6 weeks, the above four proteins were further increased. Two weeks after CCl4 injection, PDGF receptor-beta had no apparent correlation with collagen I and III. However, PDGF receptor-beta had a significant correlation with collagen I and III 2 weeks later, and the correlation coefficient was 0.74 and 0.60 respectively at 4 weeks, and 0.83 and 0.67 respectively at 6 weeks. PDGF receptor-beta had a significant correlation with a-SMA during the whole process of hepatic fibrosis and the correlation coefficient was 0.62, 0.69 and 0.81, respectively at the time of 2, 4 and 6 weeks after CCl4 injection.

CONCLUSIONThe PDGF receptor-beta was overexpressed during the process of hepatic fibrosis development, and it significantly correlated with collagen I and collagen III.

Animals ; Carbon Tetrachloride ; Carbon Tetrachloride Poisoning ; Collagen Type I ; biosynthesis ; genetics ; Collagen Type III ; biosynthesis ; genetics ; Extracellular Matrix ; metabolism ; Liver ; metabolism ; Liver Cirrhosis, Experimental ; chemically induced ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Receptor, Platelet-Derived Growth Factor beta ; biosynthesis ; genetics

OBJECTIVETo study the changes of advanced glycation end products (AGEs) in different phases of a rat liver fibrosis model induced by CCl4, and the interventional effect of aminoguanidin (AG).

METHODSFifty-four SD rats were divided into three groups: a control group, a CCl4 model group and an intervention group. Their blood serum AGEs and hyaluronic acid (HA) and AGEs in their liver homogenates were measured. These measurements were correlatively assessed to the degrees of liver fibrosis at different phases of the rat model before and after the intervention with aminoguanidin.

RESULTSThe content of AGEs in their blood sera and liver homogenates, and the level of blood serum HA, and the score of liver fibrosis degree at week 12 in our rat liver fibrosis mode groups were significantly higher than those in the control group (P < 0.01). In the intervention group with aminoguanidin, these figures were lower than those in the liver fibrosis model group (P < 0.05). The content of AGEs in their blood sera and liver homogenates had a linear correlation with the level of HA in their blood sera.

CONCLUSIONThe contents of AGEs in their blood sera and liver homogenates were increased in the late phase of our rat liver fibrosis model. To some extent, the level of AGEs may reflect the fibrosis degree of the rat livers. Aminoguanidin has an interventional effect in our CCl4 induced rat liver fibrosis model.

Animals ; Carbon Tetrachloride ; Carbon Tetrachloride Poisoning ; Glycation End Products, Advanced ; metabolism ; Guanidines ; therapeutic use ; Liver ; metabolism ; pathology ; Liver Cirrhosis, Experimental ; chemically induced ; drug therapy ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To determine whether there is an impaired Akt and eNOS activation in cirrhotic livers, and to investigate the feasibility of transferring adenovirus-mediated Akt gene to the liver for portal hypertension. METHODS: Recombinant adenovirus Ad-myr-HA-Akt and Ad-EGFP were produced by homologoas recombination in 293 cells . The Methods of compound factor, carbon tetrachloride (CCl4), corn flour, and cholesterol plus alcohol were used to construct the hepatic cirrhosis rat models. Ten normal rats were served as a normal control group, and 40 cirrhotic rats were divided into 4 groups randomly: an untreated group, an Ad-myr-HA-Akt treated group, an Ad-EGFP group, and a saline group. Ad-myr-HA-Akt, Ad-EGFP, and saline were transduced into the Ad-myr-HA-Akt treated group, Ad-EGFP group, and saline group via the tail vein respectively. Portal vein pressure, mean arterial pressure, and heart rate were measured in all rats. Protein abundance and phosphorylation status of Akt and eNOS were examined by Western blot. Spectrophotometry was used to measure the NO level. Frozen sections of the liver, heart, lung, kidney, brain, spleen, and testis were made to examine the expression of enhanced green fluorescent protein (EGFP) by fluorescence microscopy on Day 3 in the Ad-EGFP group. RESULTS: The concentration of recombinant adenovirus Ad-myr-HA-Akt after the purification was 5.5 x 10(11)vp/mL and that of Ad-EGFP was 6.0 x 10(11)vp/mL. Akt and eNOS phosphorylations in the liver of cirrhotic rats were obviously impaired. Adenoviral delivery of myr-Akt restored eNOS phosphorylation, increased the NO level and decreased the portal pressure after 3 days of adenoviral infection. In contrast, the livers infected with Ad-EGFP and saline were not changed. The EGFP expression was mainly found under the fluorescence microscopy on the frozen section of liver. Very little fluorescence was detected in the lung and kidney; and there was no detectable EGFP in other organs. CONCLUSION There is an impaired Akt and eNOS activation in the cirrhotic livers; myr-Akt gene therapy can restore the Akt activation and NO production in the cirrhotic liver, suggesting that this therapy may be helpful in treating portal hypertension.
Adenoviridae ; genetics ; metabolism ; Animals ; Carbon Tetrachloride ; Carbon Tetrachloride Poisoning ; Genetic Therapy ; Hypertension, Portal ; etiology ; therapy ; Liver Cirrhosis, Experimental ; complications ; metabolism ; therapy ; Male ; Nitric Oxide Synthase Type III ; metabolism ; Proto-Oncogene Proteins c-akt ; genetics ; Random Allocation ; Rats ; Rats, Sprague-Dawley

BACKGROUNDLiver fibrosis normally progresses to cirrhosis and destroys the normal architecture of the liver, resulting in liver dysfunction and irreversible cirrhosis. The aim of this study was to investigate the anti-fibrosis effect and the possible underlying mechanisms of decorin.

METHODSThe mice model of liver fibrosis was induced by intraperitoneal injection of 50% (v/v) of carbon tetrachloride (CCl4) diluted in olive oil (1 ml/kg body weight) once every 2 days for 5 weeks. Three weeks after injecting CCl4 intraperitoneally, mice were randomly divided into normal control with vehicles only (olive oil), mouse model given CCl4 only, and CCl4 plus decorin (DCN, 250 µg/kg). Two weeks later, all the mice were sacrificed and their liver tissues were analyzed for the expressions of genes related to liver fibrosis and under hematoxylin-eosin staining, Masson staining, and immunohistochemical staining of all groups. Aspartate transaminase, alanine transaminase, and total bilirubin of the serum were determined for evaluation of the liver function.

RESULTSExogenous protein decorin could reduce liver fibrosis induced by CCl4 in mice. The degree of fibrosis in the experimental group was alleviated, and the contents of collagen fibers were lower in the experimental group than those of the control group. In addition, expressions of transforming growth factor β1 and α-smooth muscle actin decreased in the experimental group.

CONCLUSIONSTaking liver fibrosis model of mouse as the experimental target and by injecting exogenous protein decorin into the model, we confirmed that decorin could inhibit the expression of proteins related to fibrosis and reduce the formation of liver fibrosis in mice.

Animals ; Carbon Tetrachloride ; toxicity ; Decorin ; therapeutic use ; Immunohistochemistry ; Liver Cirrhosis ; chemically induced ; prevention & control ; Mice ; Transforming Growth Factor beta1 ; metabolism

Angiotensin II ; biosynthesis ; genetics ; Animals ; Carbon Tetrachloride ; Carbon Tetrachloride Poisoning ; Curcuma ; chemistry ; Drugs, Chinese Herbal ; therapeutic use ; Liver Cirrhosis, Experimental ; chemically induced ; drug therapy ; metabolism ; Male ; Phytotherapy ; Rats ; Rats, Sprague-Dawley ; Receptor, Angiotensin, Type 1 ; biosynthesis ; genetics