Hepatic Cirrhosis In Rats Research Articles

L-Theanine prevents carbon tetrachloride-induced liver fibrosis via inhibition of nuclear factor κB and down-regulation of transforming growth factor β and connective tissue growth factor.

Here we evaluated the ability of L-theanine in preventing experimental hepatic cirrhosis and investigated the roles of nuclear factor-κB (NF-κB) activation as well as transforming growth factor β (TGF-β) and connective tissue growth factor (CTGF) regulation. Experimental hepatic cirrhosis was established by the administration of carbon tetrachloride (CCl4) to rats (0.4 g/kg, intraperitoneally, three times per week, for 8 weeks), and at the same time, adding L-theanine (8.0 mg/kg) to the drinking water. Rats had ad libitum access to water and food throughout the treatment period. CCl4 treatment promoted NF-κB activation and increased the expression of both TGF-β and CTGF. CCl4 increased the serum activities of alanine aminotransferase and γ-glutamyl transpeptidase and the degree of lipid peroxidation, and it also induced a decrease in the glutathione and glutathione disulfide ratio. L-Theanine prevented increased expression of NF-κB and down-regulated the pro-inflammatory (interleukin (IL)-1β and IL-6) and profibrotic (TGF-β and CTGF) cytokines. Furthermore, the levels of messenger RNA encoding these proteins decreased in agreement with the expression levels. L-Theanine promoted the expression of the anti-inflammatory cytokine IL-10 and the fibrolytic enzyme metalloproteinase-13. Liver hydroxyproline contents and histopathological analysis demonstrated the anti-fibrotic effect of l-theanine. In conclusion, L-theanine prevents CCl4-induced experimental hepatic cirrhosis in rats by blocking the main pro-inflammatory and pro-fibrogenic signals.

Effect of allogeneic umbilical cord mesenchymal stem cell transplantation in a rat model of hepatic cirrhosis

ObjectiveTo determine the effects of human umbilical cord mesenchymal stem cell (UCMSC) transplantation, alone or in combination with tanshinone IIA (Tan IIA) on hepatic cirrhosis in rats. MethodsA rat model of cirrhosis was established. Rats were divided into control, UCMSC, and UCSMC plus Tan IIA groups. Rats in the UCMSC group were injected via the tail vein with 0.2 mL DiI-labeled UCMSC suspension. Intraperitoneal Tan IIA injections (20 mg/kg) were started on the day of UCMSC transplantation in the UCMSC plus Tan IIA group, and continued for 7 consecutive days thereafter. Rats were sacrificed 1 day, 3 days, 1 month, and 3 months after transplantation and the numbers of DiI-labeled UCMSCs colonizing the liver were determined. Albumin (ALB) and alanine aminotransferase (ALT) levels were measured in venous blood, and mRNA and protein expression levels of human ALB and cytokeratin (CK)-18 in liver tissues were determined by reverse transcription-polymerase chain reaction and western blotting, respectively. ResultsSerum ALT levels were significantly lower and serum ALB levels significantly higher in rats in the UCMSC group compared with the control group (P < 0.05). Hepatic CK-18 and ALB mRNA and protein expression levels increased after transplantation, and were significantly higher in the UCMSC plus Tan IIA group compared with the UCMSC group (P < 0.05). ConclusionHuman UCMSCs transplanted into rats with liver cirrhosis can grow and differentiate into hepatocyte-like cells resulting in improved liver function in vivo. Tan IIA further influenced transplantation outcomes.

Thalidomide Accelerates the Degradation of Extracellular Matrix in Rat Hepatic Cirrhosis via Down-Regulation of Transforming Growth Factor-β1.

PurposeThe degradation of the extracellular matrix has been shown to play an important role in the treatment of hepatic cirrhosis. In this study, the effect of thalidomide on the degradation of extracellular matrix was evaluated in a rat model of hepatic cirrhosis.Materials and MethodsCirrhosis was induced in Wistar rats by intraperitoneal injection of carbon tetrachloride (CCl4) three times weekly for 8 weeks. Then CCl4 was discontinued and thalidomide (100 mg/kg) or its vehicle was administered daily by gavage for 6 weeks. Serum hyaluronic acid, laminin, procollagen type III, and collagen type IV were examined by using a radioimmunoassay. Matrix metalloproteinase-13 (MMP-13), tissue inhibitor of metalloproteinase-1 (TIMP-1), and α-smooth muscle actin (α-SMA) protein in the liver, transforming growth factor β1 (TGF-β1) protein in cytoplasm by using immunohistochemistry and Western blot analysis, and MMP-13, TIMP-1, and TGF-β1 mRNA levels in the liver were studied using reverse transcriptase polymerase chain reaction.ResultsLiver histopathology was significantly better in rats given thalidomide than in the untreated model group. The levels of TIMP-1 and TGF-β1 mRNA and protein expressions were decreased significantly and MMP-13 mRNA and protein in the liver were significantly elevated in the thalidomide-treated group.ConclusionThalidomide may exert its effects on the regulation of MMP-13 and TIMP-1 via inhibition of the TGF-β1 signaling pathway, which enhances the degradation of extracellular matrix and accelerates the regression of hepatic cirrhosis in rats.

Preferential increase in splanchnic sympathetic activity induced by hepatic cirrhosis in rats

Increased sympathetic activity and arterial hypotension are found in cirrhotic patients. The aim of this study was to evaluate the control of renal (rSNA) and splanchnic (sSNA) sympathetic nerve activity by the arterial baroreceptors in Wistar rats with cirrhosis induced by bile duct ligation (BDL), experiments were performed four weeks after BDL. Mean arterial pressure (MAP), heart rate (HR), rSNA and sSNA were recorded under anesthesia. The baroreflex sensitivity (BS) was assessed by the reflex changes of rSNA and sSNA induced by alterations in MAP in response to vasoactive drugs. Renal and hepatic noradrenaline was assessed by HPLC. Cirrhotic rats (CR, n=6) showed decreased MAP (control (CO, n=6):108±2 and CR:95±2mmHg) and increased HR (CO:352±10 and CR:396±13bpm). In CR group, significant increase in the basal sSNA (CO:36±8 and CR:115±13pps) accompanied by increased hepatic noradrenaline level (CO:0.7±0.1 and CR:1.4±0.1ng/mL), besides increase in the BS for PHE (CO: −0.47±0.1 and CR: −1.75±0.3) and for SNP (CO: −0.34±0.1 and CR: −1.01±0.2). However, in CR group a significant decrease in rSNA (CO:92±7 and CR:57±5pps) accompanied by no changes in rSNA BS or renal noradrenaline level (0.14±0.1ng/mL). The present study shows that in the initial phase of cirrhosis a preferential increase in sSNA appears independently of arterial baroreceptor dysfunction.Financial support: CAPES and CNPq.

Therapeutic effect of transplantation of human amniotic membrane- and umbilical cord-derived mesenchymal stem cells on hepatic cirrhosis in rats

Therapeutic effect of transplantation of human amniotic membrane- and umbilical cord-derived mesenchymal stem cells on hepatic cirrhosis in rats

Icaritin delays CCl&lt;SUB&gt;4&lt;/SUB&gt;-induced hepatic cirrhosis in rats by protecting hepatocytes from oxidative injury

Icaritin delays CCl&lt;SUB&gt;4&lt;/SUB&gt;-induced hepatic cirrhosis in rats by protecting hepatocytes from oxidative injury

Differential sympathetic activation and baroreceptor reflex sensitivity induced by hepatic cirrhosis in rats

Background/aims: Increase in sympathetic vasomotor activity and cardiovascular dysfunction has been described in patients with chronic liver disease. However, the mechanisms underlying such alterations are not fully understood. The aim of this study was to evaluate the control of renal and splancnic sympathetic nerve activity by the arterial baroreceptors in rats with cirrhosis induced by bile duct ligation (BDL).

부정항암탕(扶正抗癌湯) 추출액이 Diethylnitrosamine과 CCl4로 유발된 흰쥐의 간암 형성 및 간경화에 미치는 영향

Injinho-tang(IJ) has been used for the treatment of hepatobiliary diseases. This study was performed to observe the effect of IJ extract on the hepatocellular carcinogenesis and hepatic cirrhosis induced by Diethylnitrosamine(DENA) and in Rats. Experimental groups were divided into two ; 8th and 12th week group, and subdivided into four; normal group(Nor), hepatocellular cancer and hepatic cirrhosis inducing control group(Con), and IJ extract 260mg/kg/day(IJA) or 520mg/kg/day(IJB) administered groups to Con. The results obtained are as follows: The body weight was decreased in the Con, IJA and IJB compared with the Nor from the 2nd week to the 12th week. The weight of liver and the weight of liver/100g body weight were decreased significantly in Con, IJA and IJB compared with the Nor. The activities of aspartate aminotransferase(AST) and alanine aminotransferase(ALT) were significantly increased in the Con compared with Nor, but decreased in the IJA and IJB compared with Con from the 8th week group. The activities of alkaline phosphatase(ALP), lactacte dehydrogenase (LDH) and alpha fetoprotein(AFP) were increased significantly in the Con compared with Nor, but decreased in the IJA and IJB compared with Con. The activities of superoxide dismutase(SOD) were decreased in the IJA and IJB compared with Con, but the activities of catalase were increased in the IJA and IJB compared with Con. According to the light and electron microscopical observation, IJA and IJB improved the morphological and histopathological changes of the liver injured by DENA and . The number of hepatic p53 positive cells was decreased in the IJA and IJB compared with Con. These results suggest that administration of IJ extract suppress or retard DENA and -induced hepatocelluar carcinogenesis and hepatic cirrhosis in rats.

Effects of 1‐O‐hexyl‐2,3,5‐trimethylhydroquinone on carbon tetrachloride‐induced hepatic cirrhosis in rats

The present study was undertaken to evaluate the effects of 1-O-hexyl-2,3,5-trimethylhydroquinone (HTHQ), a synthesized vitamin E derivative, on carbon tetrachloride (CCl(4))-induced cirrhosis. Rats were treated with hypodermic injections of CCl(4) twice a week to induce the hepatic cirrhosis, and given drinking water containing HTHQ or solvent. Primary cultures of rat hepatocytes were performed to evaluate the effects of HTHQ on the expression of inducible nitric oxide synthase (iNOS). Masson's staining of rat livers showed fibrosis around pseudo-lobules in the CCl(4) group, the lesions being reduced in the CCl(4) HTHQ group. Increases in liver tissue hydroxyproline and alpha(1)(I) collagen, alpha-smooth muscle actin and iNOS induced by CCl(4), were also markedly diminished by HTHQ. Furthermore, both HTHQ and vitamin E attenuated interleukin-1beta-induced iNOS protein expression in cultured hepatocytes, the potency of HTHQ being 10-times higher than that of vitamin E. HTHQ may inhibit development of hepatic cirrhosis in rats, more potently than vitamin E, by inhibiting the iNOS expression in hepatocytes. Because vitamin E has a radical scavenging action, roles of NO and peroxynitrite will be discussed in the effects of HTHQ on the fibrosis.

Ultrastructural changes in TAA induced hepatic cirrhosis in rats

Objective To observe the ultrastructural changes in liver after portal hypertension in rats.Methods A total of 50 rats were divided into the model groups(40)and control groups(10).The rats in the model group accepted 0.03% TAA administration.Five weeks later,the concentration of TAA was changed to 0.04% for induction for 10 weeks to establish the model of portal hypertension.The pressure of superior mesenteric vein was determined and cirrhotic liver samples obtained.The ultrastructuraI changes of were observed under electron microscope.Results The fenestra quantity of endothelial cells was significantly lower in the model group(P＜0.01).The portal vein pressure was markedly higher in the control group(P＜0.01).Conclusion Hepatic sinusoid capillarization plays an important role in occurrence of portal hypertension.The fenestra of endothelial cells in hepatic sinusoid reduces and the diameter of fenestra decreases.The formation of basement membrane impaires the substance exchange between blood and hepatic cells,which results in oxygen deficiency,metabolic product accumulation and cell necrosis. Key words: Liver cirrhosis; Portal hypertension; Fenestra; Endothelial cell; Electron microscope

Reversal Effect of Thalidomide on Established Hepatic Cirrhosis in Rats via Inhibition of Nuclear Factor-κB/Inhibitor of Nuclear Factor-κB Pathway

Suppression of nuclear factor-kappaB (NF-kappaB)/inhibitor of nuclear factor-kappaB (IkappaB) signaling pathway is a potential property of thalidomide. This study was designed to investigate the effects of thalidomide on expressions of NF-kappaB, IkappaB and intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule (VCAM-1) in established rat liver cirrhosis. Rat liver cirrhosis was achieved by IP injection of carbon tetrachloride (CCl4) three times weekly for 8 weeks. CCl4 was then discontinued and thalidomide (100 mg/kg) or its vehicle was administered daily by gavage for 6 weeks. Hydroxyproline (HYP) content in liver was detected by biochemical assay. NF-kappaBp65, ICAM-1, VCAM-1 and alpha-smooth muscle actin (alpha-SMA) protein in the liver, IkappaBalpha protein in cytoplasm and NF-kappaBp65 protein in nucleus and ICAM-1, VCAM-1 mRNA levels in the liver were studied using immunohistochemistry, Western blot, and reverse transcriptase polymerase chain reaction, respectively. Compared with the spontaneous recovery of cirrhosis, the histopathology of liver of rats given thalidomide was significantly improved. HYP content in liver, the expressions of ICAM-1, VCAM-1 mRNA and protein, NF-kappaBp65 and alpha-SMA protein were decreased significantly and IkappaBalpha protein in liver was elevated significantly in this group. Thalidomide may exert its effect on downregulation of NF-kappaB-induced adhesion molecules and activation of hepatic stellate cell via inhibition of degradation of IkappaB to reverse established rat hepatic cirrhosis.

Association between portal endotoxemia and Child-Pugh classification in complex pathogens-induced hepatic cirrhosis in rats

Association between portal endotoxemia and Child-Pugh classification in complex pathogens-induced hepatic cirrhosis in rats

Alterations of mast cells and TGF-β1 on the silymarin treatment for CCl4-induced hepatic fibrosis

Silymarin is a potent antioxidant, antiinflammatory and anti-fibrogenic agent in the liver, which is mediated by alteration of hepatic Kupffer cell function, lipid peroxidation, and collagen production. Especially, in hepatic fibrogenesis, mast cells are expressed in chronic inflammatory conditions, and promote fibroblast growth and stimulate production of the extracellular matrix by hepatic stellate cells. We examined the inhibitory mechanism of silymarin on CCl(4)-induced hepatic cirrhosis in rats. At 4, 8, and 12 wk, liver tissues were examined histopathologically for fibrotic changes produced by silymarin treatment. In the silymarin with CCl(4)-treated group, increase of hepatic stellate cells and TGF-beta1 production were lower than in the CCl(4)-treated group at early stages. Additionally, at the late fibrogenic stage, expressions of TGF-beta1 were weaker and especially not expressed in hepatocytes located in peripheral areas. Moreover, the number of mast cell in portal areas gradually increased and was dependent on the fibrogenic stage, but those of CCl(1)+silymarin-treated group decreased significantly. Anti-fibrotic and antiinflammatory effects of silymarin were associated with activation of hepatic stellate cells through the expression of TGF-beta1 and stabilization of mast cells. These results suggest that silymarin prevent hepatic fibrosis through suppression of inflammation and hypoxia in the hepatic fibrogenesis.

Role of the heme oxygenases in abnormalities of the mesenteric circulation in cirrhotic rats.

Carbon monoxide (CO), a product of heme metabolism by heme-oxygenase (HO), has biological actions similar to those of nitric oxide (NO). The role of CO in decreasing vascular responses to constrictor agents produced by experimental cirrhosis induced by carbon tetrachloride was evaluated before and after inhibition of HO with tin-mesoporphyrin (SnMP) in the perfused superior mesenteric vasculature (SMV) of cirrhotic and normal rats and in normal rats transfected with the human HO-1 (HHO-1) gene. Perfusion pressure and vasoconstrictor responses of the SMV to KCl, phenylephrine (PE), and endothelin-1 (ET-1) were decreased in cirrhotic rats. SnMP increased SMV perfusion pressure and restored the constrictor responses of the SMV to KCl, PE, and ET-1 in cirrhotic rats. The relative roles of NO and CO in producing hyporeactivity of the SMV to PE in cirrhotic rats were examined. Vasoconstrictor responses to PE were successively augmented by stepwise inhibition of CO and NO production, suggesting a complementary role for these gases in the regulation of reactivity of the SMV. Expression of constitutive but not of inducible HO (HO-1) was increased in the SMV of cirrhotic rats as was HO activity. Administration of adenovirus containing HHO-1 gene produced detection of HHO-1 RNA and increased HO activity in the SMV within 7 days. Rats transfected with HO-1 demonstrated reduction in both perfusion pressure and vasoconstrictor responses to PE in the SMV. We propose that HO is an essential component in mechanisms that modulate reactivity of the mesenteric circulation in experimental hepatic cirrhosis in rats.

Prevention of hepatic cirrhosis in rats by hydroxyl radical scavengers

Background/aims : Reactive oxygen species and oxidative stress were implicated in hepatic stellate cell activation and liver fibrosis. The aim of the present study was to examine whether the administration of free radical scavengers in vivo would prevent experimentally-induced hepatic cirrhosis in rats. Methods : Cirrhosis was induced by administration of thioacetamide (TAA; 200 mg/kg, i.p.) twice/week, for 12 weeks. Rats were treated concurrently with either dimethylsulfoxide (DMSO; 4 g/kg, s.c. or p.o.) or dimethylthiourea (DMTU; 200 mg/kg i.p.) three times a week. Results : Liver fibrosis (histopathological score, spleen weight, and hepatic hydroxyproline) was abolished in rats treated with TAA and either DMSO or DMTU ( P <0.001). Accordingly, the hepatic expression of alpha smooth muscle actin, tissue inhibitor of metalloproteinase 2 and collagen type I gene were inhibited. The hepatic level of methanesulfinic acid (produced by the interaction of DMSO with hydroxyl radicals) was increased in rats treated with TAA+DMSO ( P =0.0005) and decreased after pretreatment of these rats with DMTU ( P =0.008). However, the hepatic levels of malondialdehyde, lipid peroxides and protein carbonyls were not lower in the DMSO- and DMTU-treated groups. Conclusions : The administration of free radical scavengers prevented the development of TAA-induced liver cirrhosis probably associated with decreased oxidative stress.

Different roles of free hydroxyl radicals, nitric oxide and tumor necrosis factor α in thioacetamide induced liver cirrhosis in rats

Reactive oxygen species, proinfiammatory cytokines, and nitric oxide have all been implicated in the pathogenesis of hepatic fibrosis. The aim of the present study was to examine the respective roles of these factors in the pathogenesis of thioacetamide-induced hepatic cirrhosis in rats. Methods: Liver cirrhosis was induced by intraperitoneal injections of thioacetamide (200 mg/kg) twice a week, for 12 weeks. Rats were treated concurrently with one of the following agents: the hydroxyl free radical scavenger, dimethylsulfoxide (DMSO, 4 g/kg, i.p. or p.o., 3 times a week), the anti tumor necrosis factor-~x agent pentoxifylline (PTX, 20, 100 and mg/kg, 3 times a week) or the nitric oxide synthase inhibitor N-mono-methyl arginine ester (L-NAME) (0.1 mg/ml in the drinking water), given either alone or together with pentoxifylline 20 mg/kg. Results: The degree of liver fibrosis, spleen weights and hepatic hydroxyproline levels were determined after 12 weeks in the different treatment groups, and shown in the Table:

The production of hepatic cirrhosis in rats

This study investigated the conditions necessary to produce a predictable yield of cirrhosis in rats. A previously published method, using carbon tetrachloride, was used as a basis for the study. Histopathology was used in a semi-quantitative manner to examine which observations could be used for the prediction of progression and final yield of cirrhosis. A comparison of different vehicles for oral carbon tetrachloride administration showed no effect of vehicle on the final yield of cirrhosis. Also, there were no observations during the study that should be used for prediction. Variability in the severity of hepatic impairment is an inherent feature of this model, and supporting histopathology is essential. We recommend a simple protocol for the initiation of cirrhosis in rats using carbon tetrachloride.

Antimicrobial agents in the prevention of dietary hepatic injury (necrosis, cirrhosis) in rats.

The effect of various antimicrobial agents, such as aureomycin, terramycin, streptomycin, chloromycetin, penicillin, polymyxin, and sulfaguanidine on the development of massive dietary necrosis of the liver in rats has been studied. Delay in the production of hepatic necrosis was obtained from aureomycin and, to a lesser extent, from terramycin and streptomycin. Indication of temporary protection was shown by sulfaguanidine, whereas chloromycetin, polymyxin, and penicillin were not protective. B(12), added alone, or in combination with aureomycin, to the basal experimental diet had no influence on the development of hepatic necrosis. A combination of pectin with streptomycin enhanced the protective effect of the antibiotic. All the antimicrobial agents tested, without relation to their effect on hepatic necrosis, produced temporary stimulation of growth in the experimental animals. The beneficial effect of aureomycin was not limited to the delay of hepatic necrosis but manifested itself also in the prevention of hepatic cirrhosis in rats fed a low protein (casein)-high fat diet. In contrast to control animals showing the usual combination of cirrhosis and renal changes, the rats receiving supplements of aureomycin were free of both cirrhosis and renal changes. The rats receiving aureomycin took more food in and gained weight. No microscopic alterations were seen in the pancreas of the control rats with cirrhosis. In both groups of experiments (necrosis and cirrhosis) the antimicrobial agents, with the exception of penicillin, were given mixed with the food. Their possible effect on the intestinal flora is discussed.

TREATMENT OF EXPERIMENTAL DIETARY CIRRHOSIS OF THE LIVER IN RATS

Dietary cirrhosis of the liver was produced in 223 rats, and then therapy of the condition attempted. Administration of lipotropic factors (casein, methionine, choline) was followed not only by reduction of fat infiltration and by regeneration of hepatic parenchyma but, by a reduction of the degree of the fibrosis. In one group of rats, comparison of sections obtained by biopsy, before treatment, with findings at necropsy, after completed therapy, indicated apparent reduction of the fibrosis and of the amount of ceroid and considerable restoration of architecture. This improvement, however, was obtained neither with complete regularity nor in a short time. In very severe cirrhosis, as a rule, the effect of a lipotropic diet was disappointing, even after prolonged treatment up to 200 to 240 days. It is assumed that factors determining prevention are beneficial only to a limited extent in treatment. The therapy of very severe cirrhosis may require the interaction of further beneficial factors (nutritional and hormonal). Best therapeutic results were obtained by the combination of an adequate amount of casein with methionine or liver extract, and by the combination of methionine with liver extract. Methionine and thiouracil, both of which, singly, are effective in the prevention of dietary hepatic cirrhosis in rats, have proved to be less effective for the therapy of cirrhosis, when administered together, than methionine given alone for the same purpose. Under identical conditions, female rats have shown greater resistance to the production of dietary hepatic cirrhosis and a more favorable response to therapeutic dietary factors, than male rats.

Histogenesis and Repair of the Hepatic Cirrhosis in Rats Produced on Low Protein Diets and Preventable with Choline

Histogenesis and Repair of the Hepatic Cirrhosis in Rats Produced on Low Protein Diets and Preventable with Choline