Operculina turpethum attenuates N-nitrosodimethylamine induced toxic liver injury and clastogenicity in rats

The root extract of Operculina turpethum (OTE) has been used as an anti-inflammatory, purgative, and hepato-protective agent. N-Nitrosodimethylamine (NDMA) is a potent hepatotoxin that induces fibrosis of the liver. In the present study, we examined the therapeutic effects of OTE root extract against NDMA-induced hepatotoxicity and clastogenicity in rats. Hepatic fibrosis was induced in adult male albino rats through serial intraperitoneal administrations of NDMA at a concentration of 10 mg/kg body weight on three consecutive days of each week over a period of three weeks. A group of rats received OTE orally in doses of 75, 150 and 200 mg/kg body weight at 5 h after the administration of NDMA. The controls and treated animals were sacrificed on days-7, 14 and 21 after the start of the administration of NDMA. The progression of hepatic fibrosis as well as the amelioration effect of OTE was evaluated through histopathologically as well as by immunohistochemical staining for the activation of hepatic stellate cells. Alterations in serum and liver biochemical parameters and LDH isoenzymes were also studied. Serial administration of NDMA resulted in well formed fibrosis in the liver and induction of micronuclei in the bone marrow cells. Staining of α-SMA demonstrated activated stellate cells from day-7 onwards which was dramatically increased on day-21. An elevation of micronuclei count, liver function enzymes, serum hydroxyproline levels and LDH isoenzymes 4 and 5 were also observed. All these changes were remarkably reduced in OTE administered animals and fibrogenesis was completely absent. Our results suggest that OTE has hepatoprotective and anti-clastogenic effects against NDMA-induced hepatic fibrosis. Therefore OTE may be used as a hepatoprotective agent against various liver diseases including toxic liver injury.     

The effect of oxidized isoprenaline on the chick embryonic heart

Intra-amnial administration of isoprenaline (IPRO) to chick embryos induces a number of myocardial lesions. The purpose of the present study was to investigate whether similar changes may also be induced after injection of spontaneously oxidized isoprenaline and commercially obtained adrenochrome. Cardiotoxicity of these substances has been demonstrated in adult animals. IPRO, oxidized IPRO, or adrenochrome were administered intra-amnially to 10-day-old chick embryos at doses of 0.1, 1.0, 10.0, and 100.0 mg X kg-1. Parallel experimental groups received propranolol at a dose of 1 mg X kg-1, 15 s before injection of IPRO or oxidized IPRO. The cAMP level in the heart was determined by radioimmunoassay 2 and 30 min after administration of IPRO, oxidized IPRO, or adrenochrome at a single dose of 10.0 mg X kg-1. It has been found that in embryos the effect of IPRO and oxidized IPRO is dose dependent. The rise in mortality and development of cardiomegaly together with increased hydration and disturbances of the development of coronary vascularization were highly significant starting from the dose of 10 mg X kg-1. Furthermore, both drugs significantly increased cAMP levels in the embryonic heart. On the other hand, the administration of adrenochrome was without any effect. The changes induced by IPRO were prevented by the administration of the beta-blocking agent propranolol; the lesions induced by spontaneously oxidized IPRO were, however, prevented only partially.     

Development of the controlled model of persisting infection , caused by Pseudomonas aeruginosa and bacteria of the complex Burkholderia cepacia

As the result of testing three different variants, the experimental models of persisting infection for P. aeruginosa and B. cepacia have been developed. These doses differ in the time of administration, doses of antibiotics and the infective doses of the microorganisms. The administration of the sub-inhibiting concentration of antibiotics for 5 days and the subsequent infection of laboratory animals (non-inbred mice) B. cepacia strains in a dose of LD50 leads to a considerable increase in the survival rate of mice and to a longer period (up to 20 days) of obtaining inoculative material from the spleen. The isolated cultures are characterized by a sharply slower growth on artificial culture media (up to 5-7 days as compared with 24-48 hours for the initial culture). The newly developed models have made it possible to control different stages of the infectious process in the induced increase or decrease of the virulent properties of the infective agent and in changes in the immune status of the host. As the result of these studies, in some mice (10%) infected with B. cepacia after the injection of gamma-hydroxybutyric acid lactone the infection has taken the acute form, while in the mice infected with P. aeruginosa no such effect has been observed. On the contrary, in the mice infected with P. aeruginosa and then receiving cyclophosphamide the transition of the infection into the acute form has been observed in 30% of the animals. In the mice infected with B. cepacia no such effect has been noted after the injection of this preparation. Different effects produced by cyclophosphamide and lactone are discussed from the positions of "quorum sensing" in pathogenic bacteria.     

High-fat emulsion-induced rat model of nonalcoholic steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is emerging as a common medical problem. Nonalcoholic steatohepatitis (NASH) is the critical turning point at which NAFLD progresses to more advanced stages such as hepatic fibrosis, cirrhosis and even hepatocellular carcinoma. However, the study of the pathogenic or therapeutic factors involved in NASH has been hampered by the absence of a suitable experimental model. The aim of the present work was to establish a high-fat emulsion-induced rat model of NASH. Male Sprague-Dawley rats were fed a high-fat emulsion via gavage for 6 weeks. Animals were examined for weight gain, serum and hepatic biochemistry, insulin sensitivity, hepatic malondialdehyde (MDA), superoxide dismutase (SOD) and tissue morphology, as well as cytochrome P-450 2E1 (CYP2E1) and peroxisome proliferator-activated receptor alpha (PPARalpha) expression in the liver. The results showed that rats treated with high-fat emulsion became obese, demonstrated abnormal aminotransferase activity, hyperlipoidemia, hyperinsulinemia, hyperglycemia and insulin resistance. The model rats exhibited an increased concentration of serum TNF-alpha, total cholesterol (TC), triglyceride (TG), MDA and reduced SOD levels in the liver. Immunoblot analysis showed that the expression of CYP2E1 was increased, whereas PPARalpha was reduced in the NASH model rat liver. Moreover, morphological evaluation revealed that hepatic steatosis, inflammation and mitochondrial lesions were also reproduced in this model. In conclusion, a practical and repeatable new rat model of steatohepatitis was established by feeding with high-fat emulsion via gavage. This model provides a valuable research tool and reproduces many of the clinical indices of human NASH.     

Marked reduction of Helicobacter pylori-induced gastritis by urease inhibitors, acetohydroxamic acid and flurofamide, in Mongolian gerbils.

Urease has been suggested to be essential for colonization and pathogenesis of Helicobacter pylori infection. In the present study, we evaluated the effects of urease inhibitors [acetohydroxamic acid (AHA) and flurofamide (FFA)] on H. pylori-induced gastritis in Mongolian gerbils. Animals were orally inoculated with H. pylori, and given urease inhibitors in their diet throughout the experimental period of six weeks or four weeks, starting from two weeks after H. pylori inoculation. With the administration of AHA at doses of 100, 500, and 2500 ppm throughout the experimental period, H. pylori-induced gastritis in animals was decreased in a dose-dependent manner, significantly so at 2500 ppm. Suppression of gastric lesions was also evident in animals administered 2500 ppm AHA after the H. pylori infection. Bacterial infection rates were reduced to 40-50% of the control value of 100%, by the highest dose of AHA. The potent urease inhibitor, FFA, also caused marked amelioration of H. pylori-associated gastritis on administration at 100 ppm throughout the six-week experimental period or for four weeks after H. pylori infection. Animals treated with FFA had few visible gastric lesions, and the proportion infected with H. pylori was reduced to less than 10%. Since antibiotic-resistant strains of H. pylori have become a serious problem, nonantibiotic urease inhibitors may be very useful to control H. pylori-associated gastroduodenal disease.     

Acetaminophen: a practical pharmacologic overview.

Acetaminophen is an effective analgesic and antipyretic agent with few adverse effects when used in recommended dosages. The drug is metabolized mainly in the liver, and the several end products have no harmful effects. An intermediate compound in a minor metabolic pathway, however, is toxic; it is normally inactivated by glutathione. In the case of an acetaminophen overdose the hepatic stores of glutathione seem to become depleted, leaving the toxic intermediate free to damage liver tissue. Such damage is unlikely to occur unless the plasma concentration of acetaminophen peaks above 150 micrograms/mL--a level far in excess of the 5 to 20 micrograms/mL achieved with therapeutic doses of the drug. Long-term therapeutic use of acetaminophen does not appear to be associated with liver damage, although some case reports suggest the possibility. Acetaminophen poisoning follows an acute overdose and, if untreated, is manifested clinically by an initial phase of nonspecific signs and symptoms, a latent period in which the liver transaminase levels rise and then, 3 to 5 days after the ingestion, signs of more serious hepatic dysfunction. Most patients do not progress beyond the first or second phase. They and those who survive the third phase recover with no residual injury to the liver. Appropriate antidotal therapy markedly reduces the severity of the initial damage.     

Intradermal administration of lipopolysaccharide in treatment of human cancer

 Lipopolysaccharide (LPS) has been recognized as a potent antitumor agent in animal tumor models; however, its use in human cancer therapy has been limited to only one trial, in which LPS from Salmonella was given intravenously. It was not very successful because of poor tumor response and was also toxic. We originally developed LPS prepared from Pantoea agglomerans (LPSp), and this was a well-purified, small-molecular-mass (5 kDa) agent. We chose intradermal rather than intravenous administration in the hope that the former would release LPS slowly into the bloodstream, and thus be less toxic while preserving antitumor activity. In our animal tumor models, intradermal administration was indeed less toxic and more beneficial for tumor regression than intravenous administration. We made a pilot study with intradermal administration of LPSp on the treatment of ten advanced cancer patients. Five of them had evaluable tumor, which had failed earlier to respond to conventional chemotherapy. Cyclophosphamide was also administered in this trial, in anticipation of its synergistic effect with LPSp. In this study LPSp was injected intradermally into each patient twice a week, starting with an initial dose of 0.4 ng/kg, and raising it to 600 or 1800 ng/kg. A 400-mg/m² dose of cyclophosphamide was given intravenously every 2 weeks. After completion of the dose escalation, the treatment was continued for at least 4 months, and it was found that 1800 ng/kg LPSp was well tolerated. A significant level of cytokines was observed in the sera for at least 8 h. These results indicate higher tolerable doses and remarkably more continuous induction of the cytokines than were reported in a previous study by others using intravenous administration. Three of the five evaluable tumors showed a significant response to our combined therapy. Intradermally administered, LPS was less toxic and elicited a tumor response in combination with cyclophosphamide; it can thus can be applied to cancer treatment even in humans. Received: 3 August 1995 / Accepted: 2 April 1996     

Dynamic metabolic change is indicative of inflammation-induced transformation of hepatic cells

The observation that prolonged inflammation plays a causative role in cancer development has been well documented. However, an incremental process that leads from healthy to malignant phenotypes has not yet been described. Experimentally induced hepatocellular carcinoma is considered one of the representative laboratory models for studying this process. Hepatic exposure to viral infection or toxic reagents leads to chronic inflammation and gradual transformation into hepatocellular carcinoma. Here we present metabolomic profiles of hepatic cells at different stages during inflammation-induced cellular transformation by N-nitrosodiethylamine. Using gas chromatography–mass spectrometry, we quantitatively assessed the changes in cellular metabolites during the transformation process in hepatitis and liver cirrhosis. Further pathway analysis of the differentially expressed metabolites showed that carbohydrate metabolism and lipid metabolism were greatly altered in hepatitis and liver cirrhosis, respectively. Additionally, the enhanced inflammation in cirrhosis was associated with a shift from carbohydrate metabolism to lipid and amino acid metabolism. Among the differentially expressed metabolites found in diseased mouse livers, d-glucose and d-mannitol showed the most significant changes, highlighting them as potential early-diagnostic biomarkers of hepatocellular carcinoma development. Taken together, these investigations into the dynamic metabolic changes that occur during the precancerous stages of hepatocellular carcinoma add to and refine understanding of how chronic inflammation ultimately leads to cancer. Furthermore, the findings set the stage for identifying metabolites that may serve as early-diagnostic indicators of these unfolding events.     

Potency of peroral and parenteral administration of Zinc-DTPA for decorporation of 241Am from the gastrointestinal tract

An effect of cincacine at three doses (25, 150 and 300 mumol/kg) has been studied in rats receiving 241Am citrate intragastrically. The radionuclide was introduced every other day for 2 weeks. The total content was 925 kBq/kg. A cincacine administration leads to limitation of radionuclide accumulation in the major organs of deposition independent of the modes of intake. At gastrointestinal 241Am intake peroral cincacine administration is more effective in limiting this radionuclide accumulation in skeleton but less effective in reduction of its accumulation in liver compared to parenteral cincacine. No reliable dependence of cincacine efficacy on dosage has been revealed. A morphology study of organs has shown that cincacine ingestion at a dose of 150 mumol/kg for 4 weeks and at a dose of 300 mumol/kg for 2 weeks produces a toxic effect on the small intestine mucosa. 25 mumol/kg is the optimum dose and per os administration of higher doses is not expedient.     

Human amniotic epithelial cell transplantation induces markers of alternative macrophage activation and reduces established hepatic fibrosis

Chronic hepatic inflammation from multiple etiologies leads to a fibrogenic response that can progress to cirrhosis and liver failure. Transplantation of human amniotic epithelial cells (hAEC) from term delivered placenta has been shown to decrease mild to moderate hepatic fibrosis in a murine model. To model advanced human liver disease and assess the efficacy of hAEC therapy, we transplanted hAEC in mice with advanced hepatic fibrosis. Immunocompetent C57BL/6 mice were administered carbon tetrachloride (CCl(4)) twice weekly resulting in bridging fibrosis by 12 weeks. hAEC (2 × 10(6)) were infused via the tail vein at week 8 or weeks 8 and 10 (single and double dose, respectively). Human cells were detected in mouse liver four weeks after transplantation showing hAEC engraftment. CCl(4) treated mice receiving single or double hAEC doses showed a significant but similar decrease in liver fibrosis area associated with decreased activation of collagen-producing hepatic stellate cells and decreased hepatic protein levels of the pro-fibrogenic cytokine, transforming growth factor-beta1. CCl(4) administration caused hepatic T cell infiltration that decreased significantly following hAEC transplantation. Hepatic macrophages play a crucial role in both fibrogenesis and fibrosis resolution. Mice exposed to CCl(4) demonstrated increased numbers of hepatic macrophages compared to normal mice; the number of macrophages decreased significantly in CCl(4) treated mice given hAEC. These mice had significantly lower hepatic protein levels of the chemokine monocyte chemoattractant protein-1 than mice given CCl(4) alone. Alternatively activated M2 macrophages are associated with fibrosis resolution. CCl(4) treated mice given hAEC showed increased expression of genes associated with M2 macrophages including YM-1, IL-10 and CD206. We provide novel data showing that hAEC transplantation induces a wound healing M2 macrophage phenotype associated with reduction of established hepatic fibrosis that justifies further investigation of this potential cell-based therapy for advanced hepatic fibrosis.     

Cysteamine in combination with N-acetylcysteine prevents acetaminophen-induced hepatotoxicity.

N-Acetylcysteine (NAC) is protective against acetaminophen-induced hepatotoxicity primarily by providing precursor for the glutathione synthetase pathway, while cysteamine has been demonstrated to alter the cytochrome P-450 dependent formation of toxic acetaminophen metabolite. Mice administered acetaminophen (500 mg/kg) had elevations of serum alanine aminotransferase (ALT) to 273.0 +/- 37.5 and 555.8 +/- 193.4 U/mL at 12 and 24 h, respectively, after injection. Administration of cysteamine (100 mg/kg) or NAC (500 mg/kg) significantly reduced serum ALT activity (p less than 0.001). Reducing the dose of NAC or cysteamine by 50% greatly reduced their hepatoprotective effect while the co-administration of the reduced doses of NAC (250 mg/kg) and cysteamine (50 mg/kg) following acetaminophen overdose prevented elevation of serum ALT activity (39.2 +/- 1.17 and 32.5 +/- 5.63 U/mL at 12 and 24 h post-injection, p less than 0.001) and preserved normal mouse hepatic histology. Neither NAC (500 mg/kg), cysteamine (100 mg/kg), or the lower doses in combination of both agents were found to alter the half-life or peak levels of acetaminophen. Liver microsomal aryl hydrocarbon hydroxylase activity measured 24 h after drug administration was not significantly different between treatment groups and controls receiving only saline. These results indicate a possible role for the concomitant use of NAC and cysteamine in the prevention of hepatic necrosis following toxic doses of acetaminophen. Neither decrease in plasma acetaminophen levels nor depression of cytochrome P-450 enzyme activity appears to be the mechanism of protection when these doses of NAC, cysteamine, or both drugs together are administered with a toxic dose of acetaminophen in mice.     

Hepatic production of apolar aldehydes in rats with carbon tetrachloride-induced cirrhosis

The aim of this study was to identify apolar aldehydes in liver homogenates from rats with CCl₄-induced cirrhosis and, as a corollary, the antioxidant effect of zinc administration. The study was performed in five control rats and in ten cirrhotic rats which were further sub-divided into two groups to receive either a standard diet or one supplemented with zinc. The percentage of hepatic fibrosis, plasma malondialdehyde concentration and alanine aminotransferase activity were measured as well as the following aldehydes: hexanal, octanal, decanal, 2-hexenal, 2-octenal, 2-nonenal, 2,4-heptadienal and 2,4-decadienal. Of the 10 cirrhotic rats, 4 had elevated concentrations of the highly toxic 2,4-dialkenals which coincided with a higher percentage of fibrosis and plasma alanine aminotransferase activity. These aldehydes were not observed in the control group. Zinc administration was associated with a reduction of the hepatic malondialdehyde concentration and an amelioration on the degree of hepatic injury. In conclusion, this study demonstrates the presence of the highly toxic 2,4-dialkenals in hepatic tissue of rats whith CCl₄-induced cirrhosis. Results obtained would suggest that these particular aldehydes may be related to the severity of the hepatic injury.     

Pharmacokinetics and disposition characteristics of recombinant decorin after intravenous injection into mice

The pharmacokinetics and disposition characteristics of recombinant decorin after intravenous administration were investigated in mice. Following bolus injection of 111In-labeled decorin at doses of 0.02 and 0.1 mg/kg, radioactivity rapidly disappeared from the circulation and approximately 70% of the dose accumulated in liver within 10 min. 111In-labeled decorin was preferentially localized in hepatic nonparenchymal cells. At a higher dose of 1 mg/kg, clearance from the circulation and hepatic uptake of [111In]decorin were slower than at lower doses. Both the accumulation in other tissues and urinary excretion of [111In]decorin were 5% or less. Pharmacokinetic analysis demonstrated that hepatic uptake clearance was large and accounted almost completely for total body clearance; in addition the clearance values decreased as the dose increased, suggesting that the hepatic uptake of decorin is mediated by a specific mechanism which becomes saturated at higher doses. In competitive inhibition experiments, hepatic uptake of 111In-labeled decorin was partially inhibited (about 20-30%) by several sulfated glycans such as glycosaminoglycans and dextran sulfate and by mannosylated bovine serum albumin (BSA), mannan and mannose to a lesser extent (about 10%). On the other hand, polyinosinic acid, polycytidylic acid and succinylated BSA were ineffective, suggesting that the scavenger receptor for polyanions in the liver is not involved in the hepatic uptake of decorin. A basic protein, protamine, and a ligand of the apoE receptor, lactoferrin, also had no effect. Taken together, the present results have demonstrated that recombinant decorin is rapidly eliminated from the blood circulation through extensive uptake by the liver, primarily by the nonparenchymal cells, following systemic administration. The sugar structure and mannose residue in decorin have also been suggested to play an important role in the hepatic uptake of decorin. These findings provide useful information for the development of decorin as a therapeutic agent.     

Liver engraftment potential of hepatic cells derived from patient-specific induced pluripotent stem cells

Human induced pluripotent stem cells (iPSCs) are potential renewable sources of hepatocytes for drug development and cell therapy. Differentiation of human iPSCs into different developmental stages of hepatic cells has been achieved and improved during the last several years. We have recently demonstrated the liver engraftment and regenerative capabilities of human iPSC-derived multistage hepatic cells in vivo. Here we describe the in vitro and in vivo activities of hepatic cells derived from patientspecific iPSCs, including multiple lines established from either inherited or acquired liver diseases, and discuss basic and clinical applications of these cells for disease modeling, drug screening and discovery, gene therapy and cell replacement therapy.Key words: induced pluripotent stem cells (iPSCs), hepatic differentiation, liver ngraftment, disease modeling, drug testing, alpha-1 antitrypsin, liver cirrhosis, hepatocellular carcinoma, cell therapy     

Pioglitazone prevents hepatic steatosis, fibrosis, and enzyme-altered lesions in rat liver cirrhosis induced by a choline-deficient L-amino acid-defined diet

Non-alcoholic steatohepatitis (NASH) may progress to liver cirrhosis, and NASH patients with liver cirrhosis have a risk of development of hepatocellular carcinoma. Peroxisome proliferator-activated receptor (PPAR) gamma ligand has recently been reported to have improved the condition of patients with NASH. The aim of this study was to investigate whether pioglitazone, a PPARgamma ligand, has any influence on the animal model of NASH as well as isolated hepatic stellate cells. In vivo, the effects of pioglitazone were examined using the choline-deficient L-amino acid-defined (CDAA)-diet liver fibrosis model. After two weeks, pioglitazone improved hepatic steatosis, prevented liver fibrosis, and reduced preneoplastic lesions in the liver after 10 weeks. Pioglitazone reduced the expression of TIMP-1 and TIMP-2 mRNA without changing MMP-13 mRNA expression compared to the liver fed a CDAA diet alone. In vitro, pioglitazone prevented the activation of hepatic stellate cells resulting in reducing the expression of type I procollagen, MMP-2, TIMP-1, and TIMP-2 mRNA with increased MMP-13 mRNA expression. These results indicate that pioglitazone may be one of the candidates for the benefit drugs for the liver disease of patients with NASH.     

Chemopreventive effect of orange oil on the development of hepatic preneoplastic lesions induced by N-nitrosodiethylamine in rats: an ultrastructural study

Orange peel oil is used extensively as an approved flavour enhancer in fruit drinks, carbonated beverages and as a scenting agent in soaps and cosmetics. Limonene, which is a monocyclic monoterpene is present in orange peel oil from 90 to 95% (w/w). Monoterpenes have been shown to be very effective chemopreventive agents against several rodent tumors and are currently in clinical trials. However, not much information is available regarding the ultrastructural changes associated with the chemopreventive effects of the monoterpenes. The effect of orange oil on the suppression of preneoplastic hepatic lesions during N-nitrosodiethylamine (DEN) induced hepatocarcinogenesis was studied electron microscopically. Rats were administered 200 ppm DEN through drinking water for a period of 1 month. After an interval of 2 weeks, the animals were administered orange oil by gavage for a period of 5 1/2 months. The chemopreventive effect of orange oil was monitored on the basis of liver weight profile, histological pattern by light microscopy and ultrastructural alterations by electronmicroscopy. Orange oil administration following DEN treatment showed decreased liver weights, increased intercellular gap junctional complexes, cell density and polarity when compared with only the DEN treated rats. In the present study chemopreventive effect of orange oil on DEN-induced hepatic preneoplasia in rats which is associated with the restoration of the normal phenotype and upregulation of junctional complexes has been demonstrated.     

High-dose atorvastatin causes a rapid sustained increase in human serum PCSK9 and disrupts its correlation with LDL cholesterol

Proprotein convertase subtilisin kexin type 9 (PCSK9) is a key regulator of serum LDL-cholesterol (LDL-C) levels. PCSK9 is secreted by the liver into the plasma and binds the hepatic LDL receptor (LDLR), causing its subsequent degradation. We first demonstrated that a moderate dose of atorvastatin (40 mg) increases PCSK9 serum levels, suggesting why increasing statin doses may have diminished efficacy with regard to further LDL-C lowering. Since that initial observation, at least two other groups have reported statin-induced PCSK9 increases. To date, no analysis of the effect of high-dose atorvastatin (80 mg) on PCSK9 over time has been conducted. Therefore, we studied the time course of atorvastatin (80 mg) in human subjects. We measured PCSK9 and lipid levels during a 2-week lead-in baseline period and every 4 weeks thereafter for 16 weeks. We observed that atorvastatin (80 mg) caused a rapid 47% increase in serum PCSK9 at 4 weeks that was sustained throughout 16 weeks of dosing. Importantly, while PCSK9 levels were highly correlated with total cholesterol (TC), LDL-C, and triglyceride (TG) levels at baseline, atorvastatin (80 mg) completely abolished all of these correlations. Together, these results further suggest an explanation for why increasing doses of statins fail to achieve proportional LDL-C lowering.     

Evaluation of the spontaneous reversibility of carbon tetrachloride-induced liver cirrhosis in rabbits

There is a general consensus that liver fibrosis in humans is potentially reversible, while scepticism prevails on the concept that cirrhosis can be truly reversed. The availability of suitable experimental models is fundamental for disease research. The experimental murine model of liver cirrhosis induced by carbon tetrachloride (CCl(4)) reproduces both the histological picture of the postnecrotic cirrhosis and its biochemical and clinical parameters. Normal hepatic structure is modified by formation of regeneration nodules. Fibrosis represents a morphological element of disease and an effect of hepatocyte necrosis. However, the relevance for research of this well-established model of liver cirrhosis is hampered by some spontaneous cirrhosis regression reported in mice and rats. It has been reported that CCl(4) also induces experimental liver cirrhosis in rabbits, but it is not known whether the process is reversible in this species. The aim of our study was to investigate this question. Male New Zealand White rabbits were treated intragastrically with CCl(4) or the vehicle only for 19 weeks and groups were sacrificed three and five months after treatment interruption. Cirrhotic and control livers were processed for routine light microscopy and for morphometric study of fibrosis by semiquantitative evaluation. The degree of fibrosis was based on the Knodell's scoring system.     

基于决策树的代偿期和失代偿期肝硬化自动诊断的方法

决策树方法因结构简单、便于理解和具有较高的分类精度而在数据挖掘中被广泛采用.本文利用改进的决策树算法C4.5从201例肝硬化病例中自动地提取相应的肝硬化状态识别规则,得到决策树分类模型并归纳出代偿性肝硬化和失代偿性肝硬化的诊断规则,识别正确率为84.6%.实验结果表明决策树能较好的自动从肝硬化病例中归纳出代偿性和失代偿性肝硬化的诊断规则.     

Reversal of chemical-induced liver fibrosis in Wistar rats by puerarin

Puerarin is a major isoflavonoid compound isolated from Pueraria lobata, an edible vine used widely for various medicinal purposes. It has been used for centuries in China to counteract alcohol intoxication. However, the effects of puerarin on chemical-induced liver fibrosis have not been reported. In the present study, we investigated the effects of puerarin on liver fibrosis in Wistar rats induced by alcohol plus carbon tetrachloride administration. Liver fibrosis was produced in rats by treatment with a mixture (50% alcohol, 8 g/kg per day; corn oil, 2 g/kg per day; pyrazole, 24 mg/kg per day; ig) once a day and by intraperitoneal injection of 0.25 ml/kg of a 25% solution of carbon tetrachloride in olive oil twice a week for 8 weeks. After 8 weeks, treatment with puerarin (0.4 and 0.8 g/kg ig, daily for 4 weeks) was conducted to examine its therapeutic effects. At the same time, the model group and treatment group continued to receive the chemical mixture, while the control group received saline instead of the chemical mixture. Upon pathological examination, the puerarin-treated rats significantly reversed the symptoms of liver fibrosis and other hepatic lesions. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), as indexes of hepatic cell disruption, were reduced with puerarin treatment, whereas no significant effect was discovered in the levels of alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT) activities. A significant increase in apoptosis of activated hepatic stellate cell (HSC) was found by flow cytometric analysis of the hepatic tissues. And the expression of bcl-2 mRNA was down-regulated after puerarin administration. Consequently, all these results showed that puerarin could effectively reverse chemical-induced liver fibrosis in experimental rats, via the recovery of hepatic injury as well as the induction of apoptosis in activated HSC.