Hepatoprotective effect of Spirulina platensis against carbon tetrachloride-induced liver injury in male rats

OBJECTIVES

Spirulina platensis (SP) is an edible Cyanobacterium with ethnomedicinal significance. This study aims at evaluating the beneficial effect of SP against carbon tetrachloride (CCl4)-induced liver toxicity in male rats.

METHODS

Rats received intraperitoneal injections of CCl4 (2 ml/kg body weight [b.w.] per every other day) for 40 days, alone or in combination with oral treatments of SP (400 mg/kg b.w. per day).

KEY FINDINGS

SP attenuated haematological disturbances, serum liver markers, hepatic necrosis and inflammation, and dyslipidemia in CCl4-intoxicated rats. SP also reduced CCl4-induced oxidative stress by increasing the activities of antioxidant enzymes, such as glutathione peroxidase, superoxide dismutase and catalase and glutathione content, and inhibiting lipid peroxidation products and nitric oxide levels in the rat liver. Further investigations revealed that SP counteracted CCl4-induced increased hepatic levels of Ki-67 (a parameter of cell proliferation), interleukin-6, and tumour necrosis factor-alpha and cyclooxygenase-2 messenger RNA expression. Noticeably, the supplementation of SP restored the decrease of proapoptotic p53 protein levels in the liver of rats treated with CCl4.

CONCLUSIONS

SP prevented liver damage in CCl4-treated rats via augmentation of antioxidant defense mechanisms and inhibition of inflammatory cytokines/mediators and antiproliferative effects.

Fecal microbiota transplantation prevents hepatic encephalopathy in rats with carbon tetrachloride-induced acute hepatic dysfunction

AIM

To investigate whether fecal microbiota transplantation (FMT) prevents hepatic encephalopathy (HE) in rats with carbon tetrachloride (CCl₄)-induced acute hepatic dysfunction.

METHODS

A rat model of HE was established with CCl₄. Rat behaviors and spatial learning capability were observed, and hepatic necrosis, intestinal mucosal barrier, serum ammonia levels and intestinal permeability were determined in HE rats receiving FMT treatment. Furthermore, the expression of tight junction proteins (Claudin-1, Claudin-6 and Occludin), Toll-like receptor (TLR) 4/TLR9, interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α was examined.

RESULTS

FMT improved rat behaviors, HE grade and spatial learning capability. Moreover, FMT prevented hepatic necrosis and intestinal mucosal barrier damage, leading to hepatic clearance of serum ammonia levels and reduced intestinal permeability. The expression of TLR4 and TLR9, two potent mediators of inflammatory response, was significantly downregulated in the liver of rats treated with FMT. Consistently, circulating pro-inflammatory factors such as interleukin (IL)-1β, IL-6 and tumor necrosis factor-α were remarkably decreased, indicating that FMT is able to limit systemic inflammation by decreasing the expression of TLR4 and TLR9. Importantly, HE-induced loss of tight junction proteins (Claudin-1, Claudin-6 and Occludin) was restored in intestinal tissues of rats receiving FMT treatment.

CONCLUSION

FMT enables protective effects in HE rats, and it improves the cognitive function and reduces the liver function indexes. FMT may cure HE by altering the intestinal permeability and improving the TLR response of the liver.

Renal replacement therapy in acute poisonings--one center experience

The authors described three groups of patients after acute poisonings. In the first group were 60 patients after carbon tetrachioride poisoning, the second group consisted of 81 patients after mushroom poisoning and 20 patients after ethylene glycol poisoning were in the third group. Besides two patients with rare poisonings after potassium dichromate and after paraquat poisoning were analysed. All groups of patients with the kidney damage were presented from the diagnostic, differential diagnostic, conservative, ntra- and extracorporeal elimination treatment point of view. In the group of patients suffering from acute carbon tetrachloride poisoning and with acute renal failure following therapy was used: conservative treatment, exchange blood transfusion--in 4 patients in hepatic coma, renal replacement therapy (peritoneal dialysis, haemodialysis, plasmapheresis). From the total number of 60 patients 58 survived and 2 patients died in liver coma. Survival of patients after mushroom poisoning depended on amount of oral use of mushroom (Amanita phalloides), on early admission in dialysis centre and on early beginning of renal replacement therapy within 24 hr after acute poisoning. Twenty four patients from 81 patients of this group died. Main clinical signs of ethylene glycol poisoning were various neurological symptoms (cramps, hemiparesis, coma), severe metabolic acidosis (pH = 7.06 +/- 0.14), leucocytosis (26.4 +/- 5.5x 10(9)/L) and the signs of acute toxic hepatitis and of acute renal failure. Calcium oxalic crystals in urine were present in 17 patients and leucocytosis was observed in every patient. In the first 4 patients we administered intravenously ethylalcohol as an antidotum and later in other patients we used ethylalcohol in dialysis solution. The concentration of ethylalcohol in dialysis solution was 100 mg%. Severe metabolic acidosis improved in 17 patients using bicarbonate haemodialysis and 3 patients died before the possibility to use bicarbonate haemodialysis. Eighty-four hours after acute potassium dichromate poisoning and 24 hours after exchange blood transfusion during haemodialysis a 41-year old man died in haemorhagic shock, which developed after the extensive chemical burns of mucous membrane of gastrointestinal tract caused by this poison. Our patient after paraquat poisoning was treated by repeated charcoal haemoperfusion and haemodialysis. Despite of that therapy the patient died in severe respiratory insufficiency.

In vitro and in vivo antifibrotic effects of rosmarinic acid on experimental liver fibrosis

This study was carried out to investigate whether rosmarinic acid (RA) has antifibrotic effect on experimental liver fibrosis in vitro and in vivo and its possible mechanism. Culture of hepatic stellate cells (HSCs) determine proliferation and expression of transforming growth factor-beta1 (TGF-beta1), connective transforming growth factor (CTGF) and alpha-smooth muscle actin (alpha-SMA). In carbon tetrachloride (CCL(4))-induced rat liver fibrosis model, determined biochemical indicator, liver fibrosis grade and histopathological changes, immunohistochemical detected liver TGF-beta1 and CTGF expression. The results indicated that RA could inhibit HSCs proliferation, inhibit TGF-beta1, CTGF and alpha-SMA expression in cultured HSCs. It has marked evident in reducing fibrosis grade, ameliorating biochemical indicator and histopathological morphology, reducing liver TGF-beta1 and CTGF expression in CCL(4)-induced liver fibrosis. These findings suggest that RA has potentially conferring antifibrogenic effects.

Potential therapeutic effects of a traditional Chinese formulation, BJ-JN, on liver fibrosis induced by carbon tetrachloride in rats

AIM OF THE STUDY

To evaluate the anti-fibrotic effects of BJ-JN (a traditional Chinese formulation) in CCl(4)-induced liver fibrosis in rats.

MATERIALS AND METHODS

BJ-JN (0.5, 1.0, 2.0 g/kg) was administrated via gavage once a day starting from the fifth weeks after the CCl(4) treatment for subsequent 9 weeks. Evaluated with liver and spleen index, serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronic acid (HA), nitric oxide (NO), hepatic malondialdehyde (MDA) content and superoxide dismutase (SOD) activity, as well as with histopathologic changes of liver. The proliferation and collagen synthesis of primary hepatic stellate cells (HSCs) from normal, model and BJ-JN (2.0 g/kg) treatment rats were examined with (3)H-TdR and (3)H-Pro uptake assay, respectively.

RESULTS

BJ-JN (0.5, 1.0, 2.0 g/kg) effectively reduced the elevated levels of liver and spleen index, serum ALT, AST, NO, HA, and hepatic MDA contents, enhance the reduced hepatic SOD activity in CCl(4)-treated rats. The histopathological analysis suggested that BJ-JN obviously alleviated the degree of liver fibrosis induced by CCl(4). The proliferation and collagen synthesis of HSC isolated from BJ-JN (2.0 g/kg) treatment rats were remarkably inhibited.

CONCLUSIONS

Those results suggest BJ-JN has a protective and therapeutic effect on liver fibrosis induced by CCl(4), which might be associated with its anti-oxidative activity, inhibitory activity on HSC proliferation and collagen synthesis.

Resveratrol and trimethylated resveratrol protect from acute liver damage induced by CCl4 in the rat

The importance of hydroxyl groups in the antioxidant and hepatoprotective properties of resveratrol was investigated. To achieve this, resveratrol or its trimethylated analog were administered (10 mg kg(-1), p.o.) to male Wistar rats and liver damage was induced by acute administration of CCl4 (4 g kg(-1), p.o.); appropriate controls were performed. The animals were killed 24 h after CCl4 intoxication. The amount of reduced glutathione (GSH) in the liver was not modified by any treatment; interestingly, the GSH/GSSG (oxidized glutathione) ratio decreased in the groups receiving CCl4 and resveratrol associated with an increase in GSSG. In blood GSH and the GSH/GSSG ratio were decreased by CCl4; both effects were completely prevented by any of the compounds tested. Lipid peroxidation and the activity of gamma-glutamyl transpeptidase were increased significantly after CCl4. Resveratrol partially prevented these increases and surprisingly, trimethylated resveratrol completely prevented the increase of these markers. Both compounds partially but significantly prevented the increase in the activity of alanine aminotransferase; this result agrees with observations in the histological analysis. Both tested compounds administered alone produced no effect. The results of the present study suggest that OH groups are important for the antioxidant and hepatoprotective properties of the molecule of resveratrol; nevertheless, these effects can be improved by replacing hydrogen by a methyl in these groups. The differences in the antioxidant and hepatoprotective effects of these compounds could be due to the possibility that the trimethylated resveratrol acts like a prodrug, prolonging, probably, the half-life of the original compound.

Increase of ceramide in the liver and plasma after carbon tetrachloride intoxication in the rat

In fulminant hepatic failure, various toxins causing multi-organ failure increase in plasma. As a novel toxin, levels of ceramide, a well-studied lipid mediator of apoptosis, were determined by LC-MS/MS in the liver and plasma of carbon tetrachloride (CCl4)-intoxicated rats. After 6 h of oral administration of CCl4 (4 mL/kg body weight as a 1:1 mixture of CCl4 and mineral oil) to rats, extensive hepatic failure occurred as evidenced by a severe elevation in plasma AST and ALT. The liver concentration of major ceramide components (C16:0, C24:0, C24:1, C18:0, C22:0, and C24:2 in decreasing order), and the sum of these ceramides increased significantly 2 h after CCl4 intoxication compared to that in the control group given mineral oil. The total ceramide concentration in the plasma was also increased to 4.1 times that in the control 24 h after administration of CCl4. In conclusion, the early increase in liver ceramides may contribute to hepatic cell death and the increase in plasma ceramides during fulminant hepatic failure may cause damage in other organs including the brain and kidney.

Thirteen-week inhalation toxicity of carbon tetrachloride in rats and mice

Subchronic toxicity of carbon tetrachloride (CCl4) was examined by inhalation exposure of F344 rats and BDF1 mice of both sexes to 0, 10, 30, 90, 270 or 810 ppm (v/v) CCl4 vapor for 13 wk (6 h/d and 5 d/wk). In the high exposure levels at 270 and 810 ppm, altered cell foci in the livers of both rats and mice, and fibrosis and cirrhosis in the rat liver were observed. Hematoxylin and eosin-stained altered cell foci of rats were recognized as glutathione-S-transferase placental form (GST-P) positive foci, which are preneoplastic lesions of hepatocarcinogenesis. The most sensitive endpoint of CCl4-induced toxicity was fatty change with large droplets in rats of both sexes and male mice, and cytoplasmic globules in male mice, as well as increased relative liver weight in male rats. Those endpoints were manifested at 10 ppm and the LOAEL was determined as 10 ppm for the hepatic endpoints in rats and mice. Enhanced cytolytic release of liver transaminases into plasma in rats and mice and its close association with hepatic collapse in mice were observed at medium and high levels of inhalation exposure. Both CCl4-induced hematotoxicity and nephrotoxicity were observed in both rats and mice, but those toxicities were manifested at higher exposure concentrations than hepatotoxicity. The LOAEL for the hepatic endpoint and the GST-P-stained altered cell foci provide relevant animal data for reconsidering the occupational exposure limit val1ue of 5 ppm for CCl4 and strengthen the evidence of CCl4-induced hepatocarcinogenicity which is used in its carcinogenicity classification.

Effect of the administration of fermentable and non-fermentable dietary fibre on intestinal bacterial translocation in ascitic cirrhotic rats

BACKGROUND

Bacterial infections are frequent in cirrhosis. Experimental studies suggest a pathogenic role of intestinal bacterial translocation in them. Both fermentable and non-fermentable fibre avoided intestinal bacterial translocation (IBT) in animal models of gut starvation and critical illness.

AIM

To assess the effect of fermentable (pectin) or non-fermentable (lignin) fibre on IBT in ascitic cirrhotic rats.

METHODS

Thirty-six rats induced to cirrhosis with oral CCl4 were randomized (6 weeks after the first CCl4 dose) to receive rat chow+5% lignin (LIG, n=13), rat chow+5% pectin (PEC, n=13), or rat chow only (CON, n=10). Once ascites developed, animals were laparotomized and samples of mesenteric lymph nodes (MLN), ascitic fluid, portal and peripheral blood and liver, were obtained for culture.

RESULTS

IBT rate was: LIG=5/13, PEC=4/13, CON=5/10 (P=N.S.). The median amount of translocated bacteria in rats with IBT was lower in the PEC group (2 x 10(2) CFU/g MLN), than in LIG (10(5) CFU/g MLN) and CON (10(4) CFU/g MLN) groups (P<0.05). All other samples were sterile except for a portal blood sample (Enterococcus faecalis) of the LIG group.

CONCLUSIONS

IBT incidence is not decreased by either pectin or lignin in ascitic cirrhotic rats, but pectin supplementation reduces the amount of translocated bacteria.

Toxic acute liver failure treatment by isolated hepatocytes allotransplantation in experimental

Acute liver failure treatment nowadays is a common problem in modern hepatology, despite of well studied pathogenesis and treatment modalities, lethality of the disease is still high, and in 21 century in the world's best clinics it accounts to 70-80%. For uptake of isolated hepatocytes we uses the fermental-mechanical method modified by Korukhov (1983) for the treatment of acute liver failure by hepatocyte allotransplantation and to stimulate liver reparative regeneration processes, which gives a chance to liver for the function restoration by replacement of injured hepatocytes with transplanted liver cells. We provide experiments on 45 white laboratory Vistar line rats (150-200gr) which were kept on standard environment, animals were divided into three equal groups: I group (n=20) was served as a control group, in which we provide acute liver failure modelling, by toxic agent (carbontetrachloride CCL4 ) treatment by naso-gastric tube, After acute liver failure modelling, in the II group (n=20) of animals we were conducting liver cell transplantation, III group (n=5) animals were served as donors for isolated hepatocyte uptake. Cell ultrastructure element proliferation clearly seen by morphological evaluation and animals which have acute liver failure had a chance for survival and it may be concluded that our proposed method can be the curative treatment method of acute liver failure in experiment.

Inhibition of hepatic fibrogenesis by matrix metalloproteinase‐9 mutants in mice

Tissue inhibitor of metalloproteinases-1 (TIMP-1) plays a crucial role in the pathogenesis of hepatic fibrosis and thus may represent an important therapeutic target in the design of anti-fibrotic strategies for chronic liver disease. We present an innovative therapy based on the assignment of inactivated enzymes acting as scavengers for TIMP-1. Hepatic fibrosis was induced in BALB/c mice by repetitive intraperitoneal CCl4 injection. The animals were treated with proteolytic inactive matrix metalloproteinase-9 mutants (E402Q, H401A, E402H/H411E) using adenovirus-mediated gene transfer. Application of these MMP-9 mutants inhibited fibrogenesis, which was indicated by decreasing portal and periportal accumulation of collagen. Total hydroxyproline of liver tissue, the morphometric stage of fibrosis as well as mRNA expression of marker proteins for hepatic fibrosis in livers of E402Q- and H401A-treated mice were significantly reduced. MMP-9 mutants suppressed transdifferentiation of hepatic stellate cells to the myofibroblast like phenotype in vitro and in vivo. Moreover, adenoviral application of the mutants MMP-9-H401A and -E402Q led to increased apoptosis of activated hepatic stellate cells, thought to be the main promoters of hepatic fibrosis. Application of MMP-9 mutants as TIMP-1 scavengers may provide a new therapeutic strategy for hepatic fibrosis.

Protective effect of Indigofera aspalathoides against CCl4-induced hepatic damage in rats

The alcoholic extract of stem of Indigofera aspalathoides was evaluated for its antihepatotoxic activity against CCl(4)-induced hepatic damage in rats. The activity was evaluated by using biochemical parameters, such as serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), total bilirubin and gama glutamate transpeptidase (GGTP). The histopathological changes of liver sample were compared with respective control. The extract showed remarkable hepatoprotective effect.

Lesson from the GFP/CCl4 model--translational research project: the development of cell therapy using autologous bone marrow cells in patients with liver cirrhosis

The plasticity of bone marrow has been confirmed by the analysis of autopsy findings in female recipients of bone marrow cells transplanted from male donors. To establish new clinical cell therapies using autologous bone marrow cells for patients with liver failure, we developed a new in vivo model, the "green fluorescent protein (GFP)/carbon tetrachloride (CCl(4)) model". Using the GFP/CCl(4) model, we found that transplanted Liv8-negative cells efficiently repopulated into cirrhotic liver tissue and trans-differentiated into albumin-producing hepatocytes under conditions of persistent liver damage induced by CCl(4). Moreover, one marrow cell transplantation into liver cirrhosis mice improved their liver function, ameliorated liver fibrosis, and improved their survival rate. Results from the GFP/CCl(4) model showed that cell therapy using autologous bone marrow cells has the potential to become an effective treatment for patients with liver failure. Here we describe the findings from the GFP/CCl(4) model and the scope of the translational research project.

Hepatoprotective effect of lactic acid bacteria, inhibitors of β-glucuronidase production against intestinal microflora

The hepatoprotective activity of lactic acid bacteria (Lactobacillus brevis HY7401, Lactobacillus acidophilus CSG and Bifidobacterium longum HY8001), which inhibited beta-glucuronidase productivity of intestinal microflora, on t-BHP- or CCl4-induced hepatotoxicity of mice were evaluated. These oral administration of lactic acid bacteria lowered beta-glucuronidase production of intestinal microflora as well as Escherichia coli HGU-3. When lactic acid bacteria at a dose of 0.5 or 2 g (wet weight)/kg was orally administered on CCl4-induced liver injury in mice, these bacteria significantly inhibited the increase of plasma alanine transferase and aspartate transferase activities by 17-57% and 57-66% of the CCl4 control group, respectively. These lactic acid bacteria also showed the potent hepatoprotective effect against t-BHP-induced liver injury in mice. The inhibitory effects of these lactic acid bacteria were more potent than that of dimethyl diphenyl bicarboxylate (DDB), which have been used as a commercial hepatoprotective agent. Among these lactic acid bacteria, L. acidophilus CSG exhibited the most potent hepatoprotective effect. Based on these findings, we insist that an inhibitor of beta-glucuronidase production in intestine, such as lactic acid bacteria, may be hepatoprotective.

Protective effect of Lycium chinense fruit on carbon tetrachloride-induced hepatotoxicity

In the present study, we investigated the protective effect of Lycium chinense Miller (Solanaceae) fruit (LFE) against CCl(4)-induced hepatotoxicity and the mechanism underlying these protective effects in rats. The pretreatment of LFE has shown to possess a significant protective effect by lowering the serum aspartate and alanine aminotransferase (AST and ALT) and alkaline phosphatase (ALP). This hepatoprotective action was confirmed by histological observation. In addition, pretreatment of LFE prevented the elevation of hepatic malondialdehyde (MDA) formation and the depletion of reduced glutathione (GSH) content and catalase activity in the liver of CCl(4)-injected rats. The LFE also displayed hydroxide radical scavenging activity in a dose-dependent manner (IC(50) = 83.6 microg/ml), as assayed by electron spin resonance (ESR) spin-trapping technique. The expression level of cytochrome P450 2E1 (CYP2E1) mRNA and protein, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and western blot analysis, was significantly decreased in the liver of LFE-pretreated rats when compared with that in the liver of control group. Based on these results, it was suggested that the hepatoprotective effects of the LFE might be related to antioxidative activity and expressional regulation of CYP2E1.

Effects of post low-dose X-ray irradiation on carbon tetrachloride-induced acatalasemic mice liver damage

The catalase activities in the blood and organs of the acatalasemic (C3H/AnLCsb-Csb) mouse of the C3H strain are lower than those of the normal (C3H/AnLCSa-Csa) mouse. We examined the effects of post low-dose (0.5 Gy) X-ray irradiation which reduced the oxidative damage under carbon tetrachloride-induced hepatopathy in acatalasemic or normal mice. As a result, the 0.5 Gy irradiation after carbon tetrachloride administration decreased the glutamic oxaloacetic and glutamic pyruvic transaminase activity in the acatalasemic mouse blood to a level similar to that of the acatalasemic mouse blood not treated with carbon tetrachloride; this is in contrast to a high-dose (15 Gy) irradiation. In the same manner, pathological disorder was improved by 0.5 Gy irradiation. The fat degeneration in normal mice was quickly reduced, in contrast to acatalasemic mice. These findings suggest that low-dose irradiation after carbon tetrachloride administration accelerates the rate of recovery and that catalase plays an important role in the recovery from hepatopathy induced by carbon tetrachloride, in contrast to high-dose irradiation.

[Morphological and functional characteristics of thyroid gland in the offspring of female rats with experimental chronic liver disease of various etiology]

The peculiarities of structural and functional development of the thyroid gland were studied in the offspring of female rats with experimental chronic liver disease. Morphometric methods as well as immune enzyme analysis were used. Impairment in the development of thyroid gland structure was found in experimental animals, as evidenced by lower magnitudes of volume density of follicular and intrafollicular epithelium, as well as by reduced values of thyrocyte height. Morphological changes of the thyroid gland in the offspring of female rats with chronic liver disease were accompanied by the impairment of the gland endocrine function (decreased serum levels of T3 and T4).

Protective effects of melatonin against carbon tetrachloride hepatotoxicity in rats

Melatonin is an indolamine, mainly secreted by the pineal gland into the blood of mammalian species. The potential for protective effects of melatonin on carbon tetrachloride (CCl(4))-induced acute liver injury in rats was investigated in this work. CCl(4) exerts its toxic effects by generation of free radicals; it was intragastrically administered to male Wistar rats (4 g kg(-1) body weight) at 20 h before the animals were decapitated. Melatonin (15 mg kg(-1) body weight) was administered intraperitoneally three times: 30 min before and at 2 and 4 h after CCl(4) injection. Rats injected with CCl(4) alone showed significant lipid and hydropic dystrophy of the liver, massive necrosis of hepatocytes, marked increases in free and conjugated bilirubin levels, elevation of hepatic enzymes (alanine aminotransferase and aspartate aminotransferase) in plasma, as well as NO accumulation in liver and in blood. Melatonin administered at a pharmacological dose diminished the toxic effects of CCl(4). Thus it decreased both the structural and functional injury of hepatocytes and clearly exerted hepatoprotective effects. Melatonin administration also reduced CCl(4)-induced NO generation. These findings suggest that the effect of melatonin on CCl(4)-induced acute liver injury depends on the antioxidant action of melatonin.

[Therapeutic effect of "anti-hepatic-fibrosis 268" on hepatic fibrosis in rats]

OBJECTIVE

To investigate the effects of the proprietary Chinese Medicine "anti-hepatic-fibrosis 268" on hepatic fibrosis and the related mechanisms.

METHODS

The model of CCl4-induced hepatic damage was established in SD rats. 54 male rats were divided into four groups, namely high dose and low dose "anti-hepatic-fibrosis 268" groups, colchicine control group, and model control group. Using Masson stain and light microscope, the authors examined the rats' hepatic tissues and counted the hepatic fiber components, then examined and counted TGF-beta1, alpha-SMA, FN, Type I, III collagen by means of immunohistochemical technique. The groups were compared and the internal relationships of the data were analyzed.

RESULTS

The levels of FN, LN, Type I and III collagen, TGF-beta1, and alpha-SMA of the CCl4 damaged rats increased (P<0.01). After 3 weeks of high dose "anti-hepatic-fibrosis 268" treatment, the levels of TGF-beta1, alpha-SMA, FN, LN, Type I and III collagen decreased (P<0.01) and the degree hepatic fibrosis took a favorable turn significantly (P<0.05) as compared with the model control. In the rats of the low dose group, the levels of TGF-beta1, alpha-SMA, FN, Type III collagen significantly decreased (P<0.05), the levels of LN, Type I collagen were not different from the model control; The hepatic fibrosis improved to a certain extent (P<0.05).

CONCLUSION

The mechanism of reversing hepatic fibrosis by "anti-hepatic-fibrosis 268" in this experiment is that the medicine regulates TGF-beta1 and further affects alpha-SMA, thus resulting in the decline of FN, Type I, III collagen levels in liver extracellular matrix.

[Pathological study of the therapeutic effect of wen-yang herbs on experimental liver cirrhosis]

OBJECTIVE

To observe the pathological effect of wen-yang herbs on experimental hepatic fibrosis.

METHODS

Thirty-two male Wistar rats were used in this study comprising four groups. To start with, 24 rats of three groups were given subcutaneous injection of CCl4 and drinking 10% alcohol so as to make the model of hepatic fibrosis. After the establishment of the pathologic model, the rats were divided into the model group, the pathological control group and the therapeutic group by randomization. The rats of the therapeutic group were given the herbal remedies via gastrogavage, q.d. x 30. The rats of the pathological control group were given normal saline via gastrogavage, q.d. x 30. Then liver tissue Hydroxyproline (Hyp) content was examined in these 3 groups and the normal group. Quantitative marks were done according to a modified semiquantitative scoring system (SSS). The results of SSS marks and Hyp contents were analysed using Pearson's coefficient of correlation.

RESULTS

The Hyp content and SSS marks of the therapeutic group decreased remarkably as compared with those of the control group (P<0.01), and the SSS marks had a strong positive correlation with Hyp content (r=0.804).

CONCLUSION

Wen-yang herbs can mitigate the rats' hepatic fibrosis and promote a recovery of their experimental illness.

The effects of allyl sulfides on the induction of phase II detoxification enzymes and liver injury by carbon tetrachloride

Allyl sulfides, e.g., diallyl sulfide (DAS), diallyl disulfide (DADS), and diallyl trisulfide (DATS), are principal constituents of garlic oil. In the present study, we investigated the in vivo effect of these sulfides on the phase I and phase II drug-metabolizing enzymes, and elucidated their structure-function relationship. A highly purified form of each sulfide (more than 99% purity) was administered i.p. as a bolus to rats at a concentration of 10 or 100 micromol/kg body weight for 14 consecutive days. As to the phase I enzymes, DAS (100 micromol/kg) slightly but significantly increased cytochrome P-450 (CYP) 2E1 activity (1.6-fold vs. control), whereas DADS and DATS did not affect it or the hepatic total CYP level or CYP1A1/2 activity. With respect to the phase II enzymes, DATS (10 micromol/kg) and DADS at a 10-fold higher dose (100 micromol/kg) significantly increased the activities of glutathione S-transferase, quinone reductase, and antioxidative enzyme glutathione peroxidase; whereas DAS did not. In the carbon tetrachloride (CCl4)-induced acute liver injury model of rats, either DATS (10 micromol/kg) or DADS (100 micromol/kg) significantly reduced the injury caused by the induction of phase II enzymes with CCl4. In conclusion, the sulfides affected both phase I and phase II enzymes, the former being stimulated by the monosulfide only and the latter, strongly by the trisulfide and weakly by the disulfide. Therefore, the polysulfide DATS may be one of the important factors in garlic oil that protects our body against the injury caused by radical molecules encountered in daily life.

Induction of Mx-2 in rat liver by toxic injury

BACKGROUND/AIMS

Mx proteins are supposed to be strictly regulated by viruses or interferon-alpha (IFN-alpha). We used a non-viral model of acute liver injury to study Mx expression.

METHODS

We induced toxic liver injury by CCl(4), and studied the expression of IFN-alpha, IFN-gamma, and IFN-inducible antiviral genes (Mx-2; 2'-5' oligoadenylate synthetase, 2-5 A; double-stranded RNA-activated protein kinase, PKR).

RESULTS

Similar to 2-5 A and PKR, Mx-2 gene expression was biphasically induced after CCl(4) administration with a maximum at 24 h, and a second peak at 72 h. On protein level, Mx-2 only was up-regulated. IFN-alpha remained constant for the first 24 h while IFN-gamma peaked at 6 h. Thereafter, IFN-alpha increased to a maximum at 72 h while IFN-gamma decreased to 77+/-4%. Small monocyte-like liver macrophages, but not large macrophages, expressed Mx-2 constitutively. In vitro, IFN-alpha but not IFN-gamma induced Mx-2 in different liver cell populations. IFN-gamma, instead, reduced the susceptibility of liver macrophages to the actions of IFN-alpha.

CONCLUSIONS

Our data suggest that Mx expression does not invariably result from the presence of a viral particle or IFN-alpha synthesis but may represent an innate defensive armamentarium that may be up-regulated without antigen specificity upon liver injury.

[Antioxidant action of oligomeric proanthocyanidins isolated from viburnum in liver lesions by carbon tetrachloride and prevention of the latter's toxicity]

The effect of a set of oligomeric anthocyanidins, isolated from viburnum, produced on the indices of lipid metabolism, lipid peroxidation (LPO) and on the hepatic antioxidant system in rats, who were subjected to the impact of carbon tetrachloride (CTC), was studied versus such effect exerted by preparations "Piknogenol" and "Legalon". The set of oligomeric anthocyanidins had a pronounced antitoxic and antioxidant action preventing the development of fat infiltration of the liver. The discussed preparation inhibited the processes of LPO, it normalized the level of antiradical hepatic activity and had a pronounced glutathione-saving effect, which is preconditioned by the biological activity of oligomeric anthocyanidins (traps for free radicals). The preparation can be used in prevention and treatment of toxic hepatic lesions.

Central injection of astressin inhibits carbon tetrachloride-induced acute liver injury in rats

The effect of intracisternal astressin, a specific and potent corticotropin-releasing factor (CRF)(1) and CRF(2) receptor antagonist on carbon tetrachloride (CCl(4))-induced acute liver injury was investigated in rats. Intracisternal astressin inhibited the elevation of serum alanine aminotransferase level induced by CCl(4). Intracisternal astressin also reduced CCl(4)-induced liver histological changes. The protective effect of central astressin on CCl(4)-induced liver damage was abolished by sympathectomy but not by hepatic branch vagotomy. These findings demonstrate that astressin acts in the central nervous system to induce hepatic cytoprotection, possibly through the sympathetic pathways in rats. These results further establish a role of endogenous CRF in the brain in hepatic pathophysiological regulation.

[Dynamics of glycogen content in the normal and cirrhotic liver following glucose administration to starving rats]

Using biochemical, cytofluorimetric and television cytophotometric methods, glycogen contents were studied in normal and cirrhotic rat liver at various intervals after glucose administration to fasting animals. The obtained data indicate that after a 48 h fasting glycogen contents in normal and cirrhotic liver are equally poor. A marked rise of glycogen content in cirrhotic liver was observed only 20-30 min after glucose administration to rats. It has been established that at all intervals after glucose administration to rats hepatocytes of the portal lobule zone, both in normal and in cirrhotic liver, accumulate more glycogen than those of the central zone. Again, the intensity of glycogen accumulation in cirrhotically altered liver is significantly lower than in normal liver, due, presumably, to a lower rate of glycogen synthesis in pathologically changed liver.

[Glutamine metabolism in the brain and in the liver in critical conditions]

Experiments on cats and rats have established that critical conditions caused by acute hemorrhage, hepatotoxin, and hepatectomy lead to ammonia accumulation in the brain and liver due to the predominance of decay of glutamine over its formation in these organs. With this, the depressed formation of glutamine is a universal cell response to a pathogenic agent whereas a change in glutamine deamination in disease depends on both the nature of a pathogenic agent and the organ wherein this reaction occurs.

[Relationship of propranolol pharmacokinetic parameters with portosystemic shunt in CCl4-induced cirrhotic rats]

BACKGROUND/AIMS

This study was designed to determine the relationship of propranolol pharmacokinetic parameters with portosystemic shunt in CCl4-induced cirrhotic rats.

METHODS

Cirrhotic rats(n=6) were induced by intramuscular injection of CCl4 in olive oil(two time per weeks) for 12 weeks. Controls (n=6) were injected intramuscularly with the same dose of olive oil for 12 weeks. We evaluated the amount of portosystemic shunt by thallium-201 per rectal scintigraphy. After intravenous bolus injection of propranolol (2mg/kg) to rats, the serum propranolol concentrations were analyzed by a HPLC-fluorimetric detector system. Pharmacokinetic parameters such as C0, AUC, t1/2(beta), and CLp were determined in each group. Then, a small amount of heptic tissue was obtained and subjected to determination of the hepatic collagen content by quantitating 4-hydroxyproline and were inspected by microscope after hematoxylin and eosin stain.

RESULTS

In liver biopsy, liver fibrosis progressed in CCl4-induced cirrhotic rats. The serum concentrations of propranolol were significantly (p < 0.01) elevated in CCl4-induced cirrhotic rats. Mean amount of 4-hydroxyproline, mean H/L ratio, and mean AUC in CCl4-induced cirrhotic rats was significantly (p < 0.01) higher than that in control rats. There was a relationship between AUC, H/L ratio, and amount of 4-hydroxyproline.

CONCLUSION

H/L ratio may help in the selection of drug dosage (especially blood flow dependent drug) in pre-clinical studies for chronic liver disease during the drug development process.

[Effect and mechanism of action of Tinospora bakis roots on biliary secretion using in vivo models]

The aim of this study is to determine the choleretic properties of lyophilized aqueous extract of Tinospora bakis roots. For thus, we have used healthy and cholestatic Wistar rats. After administration of the extract (4 mg/100 g of weight) biliary flow, biliary acids flow, biliary glutathione and glucose concentrations were measured by specific methods. Comparative results between treated rats and non treated rats show: For healthy rats: a significant increase of biliary flow, biliary acids flow in the group of treated rats versus non treated healthy rats. There were no significant difference in the glutathione and glucose concentrations. For cholestatic rats: we noted also significant increase of biliary flow, biliary acids flow and glutathione concentration in the treated rats group. These results suggest that Tinospora bakis has a choleretic effect in vivo which depends on biliary acids and/or glutathione concentration.

[An experimental model of hepatic fibrosis induced by alcohol and CCl4: can the lipopolysaccharide prevent liver injury induced by alcohol and CCl4?]

BACKGROUND/AIMS

It is well known that alcohol enhances the toxicity of CCl4. We tried to establish an alcoholic liver cirrhosis model by administration of alcohol and CCl4 to rats. We also wanted to know the hepatoprotective effect of low doses of lipopolysaccharide(LPS) in this animal model.

METHODS

Of 20 female adult rats, 8 were ingested with alcohol ad libitum(group 1) Another 6 were ingested with 10% alcohol and 50% 1mL/kg CCl4 intragastrically by Sonde twice a week(group 2) The remaining 6 were ingested with 10% alcohol, CCl4, and 0.1mg/kg LPS intraperitoneally twice a week(group 3) The fibrosis was evaluated semiquantitatively on a scale of 0(none) to 3(cirrhosis).

RESULTS

1) After 10 weeks, septal fibrosis or cirrhosis was produced in 9 out of 12 rats in groups 2 and 3 but there was no fibrotic change in group 1. 2) There was no significant difference in pathological grading between groups 2 and 3.

CONCLUSIONS

Hepatic fibrosis or cirrhosis can be sufficiently induced by alcohol and repetitive CCl4 ingestion for 10 weeks. We can not prove the hepatoprotective effect of low dose LPS by semiquantitative evaluation of pathological grading.

Hepatoprotective activity of Trichilia roka on carbon tetrachloride-induced liver damage in rats

Trichilia roka Chiov. (Meliaceae) is a tree widely distributed in tropical Africa. It has been used in Mali folk medicine for the treatment of various illnesses. A decoction of the roots is taken as a remedy for colds and pneumonia, and it is used as a diuretic and in hepatic disorders. We have evaluated the hepatoprotective effects of a decoction of Trichilia roka root on CCl4-induced acute liver damage in rats. Treatment with the decoction showed a significant protective action made evident by its effect on the levels of glutamate oxalacetate transaminase and glutamate pyruvate transaminase in the serum, on the protein content and lipid peroxidation levels in the liver homogenate. Histopathological changes produced by CCl4, such as necrosis, fatty change, ballooning degeneration and inflammatory infiltration of lymphocytes around the central veins, were clearly recovered by the treatment with Trichilia root decoction. On fractionating this extract into diethyl ether-soluble and water-soluble fractions, the activity was retained in the diethyl ether-soluble fraction. Moreover, the administration of decoction prevented a preferential deposition of collagen around the sinusoidal cell layer, which is responsible for the perisinusoidal fibrosis in the early stage of CCl4 damage. This study showed that treatment with Trichilia roka extracts or silymarin (as reference) appeared to enhance the recovery from CCl4-induced hepatotoxicity. The hepatoprotective properties of Trichilia roka may be correlated to polyphenol content of the decoction and its diethyl ether-soluble fraction.

[Effectiveness of dietary non-starch polysaccharides in experimental toxic hepatitis]

The efficiency of some polysaccharides was investigated in mice with an experimental toxic hepatitis. Hepatitis was induced by the oral administration of 10% solution CCl4 in olive oil at a dosage of 3 ml/kg body weight every day during 7 days. After that tested substances were administrated every day 30-40 min before a feeding at a dosage of 150 mg/kg body weight during 14-21 days. Results showed that a calcium alginate, two low-methoxyl pectins (one with the degree of esterification about 50% and other with the degree of esterification less 5%), fucoidan, and chitozan, but not lambda-carrageenan and kappa-carrageenan, have beneficial affects on liver total lipid, glycogen, malondialdehyde, and diene conjugates as well as on blood total lipid and alanine aminotransferase activity in animals with experimental toxic hepatitis.

S-adenosylmethionine prevents hepatic tocopherol depletion in carbon tetrachloride-injured rats

In various experimental models, S-adenosylmethionine (SAMe) has been shown to reduce liver injury by preventing depletion of glutathione, one of the antioxidant systems that plays a critical role in defence against oxidative stress. On the other hand, alpha-tocopherol may be decreased in liver diseases, and treatment with this vitamin reduces liver injury in CCl(4)-treated rats. Since there is a close relationship among the different antioxidant systems (mainly glutathione, alpha-tocopherol and ascorbic acid), we have assessed whether, as well as restoring hepatic glutathione content, SAMe has any effect on liver alpha-tocopherol and ascorbic acid levels in CCl(4)-injured rats. Four groups of seven male Wistar rats treated for 9 weeks were studied: rats induced to cirrhosis with CCl(4), rats induced to cirrhosis plus SAMe administration (10 mg x kg(-1) x day(-1)) and their respective controls. Liver samples were obtained for measuring levels of glutathione, alpha-tocopherol, ascorbic acid and thiobarbituric acid-reactive substances (TBARS), and hydroxyproline concentration as an index of collagen content. The hydroxyproline content was higher in CCl(4)-injured rats than in the control group (4.4+/-1.8 and 1.1+/-0.3 micromol/g respectively; P<0.05). In CCl(4)-injured rats, SAMe administration decreased collagen content (2.7+/-1.0 microl/g; P<0.05) and TBARS, and corrected glutathione depletion. alpha-Tocopherol was significantly lower in CCl(4)-injured rats than in controls (17.3+/-4.9 and 23.0+/-4.0 micromol/g respectively; P<0.05). By contrast, alpha-tocopherol levels were similar (23.8+/-5.1 micromol/g) in CCl(4)-injured rats receiving SAMe and in controls. In CCl(4)-injured rats, liver ascorbic acid was decreased in comparison with controls (4.9+/-1.8 and 8.2+/-1.0 micromol/g respectively; P<0.05), levels which were not replenished by SAMe (4.6+/-0.4 micromol/g). In conclusion, SAMe not only decreases fibrosis and protects against hepatic glutathione depletion, but has a further antioxidant effect of preventing alpha-tocopherol depletion in CCl(4)-injured rats.

Hepatoprotective effects of bergenin, a major constituent of Mallotus japonicus, on carbon tetrachloride-intoxicated rats

The hepatoprotective effects of bergenin, a major constituent of Mallotus japonicus, were evaluated against carbon tetrachloride (CCl(4))-induced liver damage in rats. Bergenin at a dose of 50, 100 or 200 mg/kg was administered orally once daily for successive 7 days and then a mixture of 0.5 ml/kg (ip) of CCl(4) in olive oil (1:1) was injected two times each at 12 and 36 h after the final administration of bergenin. The substantially elevated serum enzymatic activities of alanine/aspartate aminotransferase, sorbitol dehydrogenase and gamma-glutamyltransferase due to CCl(4) treatment were dose dependently restored towards normalization. Meanwhile, the decreased activities of glutathione S-transferase and glutathione reductase were restored towards normalization. In addition, bergenin also significantly prevented the elevation of hepatic malondialdehyde formation and depletion of reduced glutathione content in the liver of CCl(4)-intoxicated rats in a dose dependent fashion. The results of this study clearly indicate that bergenin has a potent hepatoprotective action against CCl(4)-induced hepatic damage in rats.

Antihepatotoxic activity of bergenin, the major constituent of Mallotus japonicus, on carbon tetrachloride-intoxicated hepatocytes

To determine the antihepatotoxic activity of bergenin from Mallotus japonicus, carbon tetrachloride (CCl4)-induced cytotoxicity in primary cultured rat hepatocytes has been adopted as an assay system. Bergenin significantly reduced the activities of glutamic pyruvic transaminase and sorbitol dehydrogenase released from the CCl4-intoxicated hepatocytes. The antihepatotoxicity of bergenin was also evidenced by elevating the activities of glutathione S-transferase and glutathione reductase, and content of glutathione in the CCl4-intoxicated hepatocytes. From these results, it is assumed that bergenin exerted antihepatotoxicity against CCl4-induced cytotoxicity through glutathione-mediated detoxification as well as free radical suppressing activity.

Alleviation of carbon tetrachloride-induced chronic liver injury and related dysfunction by L-tryptophan in rats

We examined whether L-tryptophan (Trp) alleviates carbon tetrachloride (CCl4)-induced chronic liver injury and related dysfunction. Fifty rats were classified into four groups: the first (15 rats) served as the control; the second (10 rats) received subcutaneous injections of CCl4 (1.0 mL/kg) twice weekly for 8 weeks; the third (15 rats) received daily intraperitoneal injections of Trp (50 mg/kg) for 2 weeks after 6 weeks of CCl4 treatment; the fourth (10 rats) received both treatments. The activities of serum transaminases and the content of liver total hydroxyproline increased after 6 and 8 weeks of CCl4 treatment. The concentrations of serum albumin and liver protein and the in vitro activity of liver protein synthesis fell after 8 weeks of the treatment. Trp administration alleviated all these changes. At 6 and 8 weeks of CCl4 treatment the serum triglyceride concentration fell, whereas the liver triglyceride and lipid peroxide concentrations were elevated. Trp administration hardly affected these changes. These results indicate that Trp alleviates CCl4-induced chronic liver injury possibly by maintaining the activity of protein synthesis.

[The specific activity of new drug forms of dibunol]

The specific activity of new drug forms (tablets, suppositories, ointments) of dubinal was studies on models of ischemic damage to the heart, toxic hepatitis, aseptic inflammation, damage to the skin and mucosa of the large intestine. It was found that the drug forms under study possessed a cardioprotective, hepatoprotective, anti-inflammatory, and wound-healing effect. This may serve as a prerequisite to their further clinical study.

[The joint use of prednisolone and phospholipid-containing hepatoprotectors in experimental chronic hepatitis]

In chronic CCl4-hepatitis in rats phospholipid-containing hepatoprotectors, essentiale and eplir differ in their influence on the therapeutic effect of prednisolone; essentiale does not change the antiproliferative effect of the glucocorticoid and weakens its membrane-stabilizing effect, eplir increases these therapeutic effects of prednisolone. Besides, eplir, in distinction from essentiale, reduces lipid accumulation in the liver and hypoproteinemia which are induced by prednisolone.

Effectiveness of recombinant human serum albumin in the treatment of ascites in liver cirrhosis: evidence from animal model

1. To investigate the effectiveness of recombinant human serum albumin (rHSA) in the treatment of ascites in liver cirrhosis, we examined its effect on rats with carbon tetrachloride-induced liver cirrhosis. 2. Twenty-five percent rHSA was administered intravenously at a dose of 0.25 to 1.0 g/kg for 2 days to rats with liver cirrhosis accompanied by ascites retention and hypoalbuminemia. 3. rHSA dose dependently decreased abdominal circumference, a clinical index of ascites, with significant difference at a dose of 1.0 g/kg. 4. Although there was no significant difference, rHSA increased blood colloid osmotic pressure (b-COP) and urine volume (UV) in a nearly dose-dependent manner, with significant negative correlation between changes from baseline value in these parameters and in abdominal circumference. 5. These findings suggest that rHSA has abdominal circumference-decreasing action associated with b-COP improvement and UV increase and that it could be effective as a therapeutic drug for ascites in patients with liver cirrhosis accompanied by hypoalbuminemia.

Endothelial dysfunction and decreased production of nitric oxide in the intrahepatic microcirculation of cirrhotic rats

Increased intrahepatic resistance in cirrhotic livers is in part caused by increased vascular tone. Several morphological abnormalities have been described in the sinusoidal endothelial cells of cirrhotic livers, but the functional impact of these abnormalities on the intrahepatic vascular tone has not been studied. The aim of this study was to investigate the intrahepatic endothelial function and the role of nitric oxide (NO) with regard to vascular tone in cirrhotic livers. Isolated rat liver perfusions were performed in cirrhotic rats (induced by chronic carbon tetrachloride inhalation) and weight-matched normal controls. After preconstricting the intrahepatic microcirculation with methoxamine (10(-4) mol/L), response to cumulative doses of receptor-mediated endothelial agonist, acetylcholine (10(-7) mol/L-10(-5) mol/L), was obtained. In another series, response to the receptor-independent endothelial agonist, calcium ionophore A23187 (10(-7) mol/L and 3 x 10(-7) mol/L), was obtained in the absence and presence of Nomega-nitro-L-arginine (NNA) and indomethacin. In a third series of rats, nitrate and nitrite production was measured in the perfusate of perfused normal and cirrhotic livers. There was significantly less vasorelaxation in cirrhotic livers as compared with normal livers in response to acetylcholine and calcium ionophore A23187 (P < .0001). The impaired vasorelaxation was a result of a decrease in both NO-mediated and non-NO-mediated components of vasorelaxation. Cirrhotic livers from ascitic rats had significantly less vasorelaxation as compared with livers from nonascitic rats (P < .005). There was significantly less production of nitrates and nitrites in cirrhotic livers (P < .05). The liver microcirculation of cirrhotic livers is characterized by endothelial dysfunction that results in impaired release of endothelial relaxing factors including NO.

[The hepatoprotective action of ellagotannins]

The hepatoprotective properties of altan (obtained on the basis of ellagotannines from the cones of black alder Alnus glutinosa) are studied on the model of acute damage to the liver with tetrachloromethane. It is found that altan exhibits the hepatoprotective activity even in a dose of 1 mg/kg which is tenfold smaller compared to the dose of traditional flavonoid-based drugs. Altan limits choleopoiesis disorder, has an antiinflammatory and membrane stabilizing effect, and recovers physiological antioxidant system.

Effects of long-term administration of interferon alpha in two models of liver fibrosis in rats

BACKGROUND/AIMS

The aim of this study was to assess the effect of the early and chronic administration of interferon alpha in the prevention of hepatic fibrosis and portal hypertension.

METHODS

Rats with liver fibrosis due to bile duct ligation or CCl4 were divided into three groups: sham, placebo and interferon alpha2a 100,000 UI/day. Liver fibrosis was assessed by the area of fibrosis (image analysis), liver hydroxyproline and mRNA (fibronectin, procollagen alpha2(I)) contents, and serum hyaluronate. Systemic and splanchnic hemodynamics were also evaluated.

RESULTS

Interferon alpha significantly decreased fibrosis in the CCl4 model only: area of fibrosis: 13.9+/-3.7 vs 10.5+/-3.3% (p<0.05), hydroxyproline: 1.8+/-0.6 vs 1.2+/-0.2 mg/g wet liver (p<0.001), respectively placebo vs interferon alpha. There was a significant correlation between the area of fibrosis and hydroxyproline liver content (r=0.77 in the biliary model and r=0.87 in the CCl4 model, p<0.0001). Interferon decreased spleno-renal shunt blood flow (2.0+/-1.8 vs 0.9+/-0.7 ml/min; p<0.05) but not portal pressure in the CCl4 model. No significant effects were observed in rats with biliary fibrosis.

CONCLUSIONS

The early and chronic administration of interferon alpha prevents the development of liver fibrosis and porto-collateral circulation in the CCl4 model but not in the biliary model. However, the antifibrotic effects of interferon need to be confirmed in further studies.

Oral supplementation with branched-chain amino acids improves survival rate of rats with carbon tetrachloride-induced liver cirrhosis

We investigated whether supplementation with branched-chain amino acids (BCAA) improves survival of rats with carbon tetrachloride (CCl4) -induced cirrhosis. Liver cirrhosis was induced in 40 male Sprague-Dawley rats by administering CCl4 for 15 weeks. Twenty rats each were then assigned to the control and BCAA group and fed a casein diet or a BCAA-supplemented casein diet, respectively, for an additional 17 weeks with repeated injections of CCl4. No significant difference occurred in either mean energy or nitrogen intake or in body or liver weight between the two groups. BCAA-supplementation significantly preserved plasma albumin concentrations (P < 0.05) and inhibited significantly the occurrence of ascites and hyperammonemia (P < 0.05). The survival rate was significantly higher in the BCAA group (P=0.03), while no significant difference was found in liver histology between the groups. These results suggest that BCAA improved survival of rats with CCl4-induced cirrhosis by preventing hypoalbuminemia and hyperammonemia without directly reducing hepatic necrosis and fibrosis.

[Rehabilitation of the hepatocyte glycogen-forming function in the rat cirrhotic liver due to carbohydrate rich diet]

By cytofluorometric and biochemical methods the content of total glycogen and its fractions was investigated on the smears of isolated liver cells: labile fraction (LF) and stable fraction (SF) and also activities of glycogen phosphorylase (GP), glucose-6-phosphatase (G-6-Pase) and glycogen synthase. The material was obtained from serial liver biopsies from each investigated animal prior to CCl4 action (control), with cirrhosis (6 months of CCl4 poisoning) and 1, 3 and 6 months after CCl4 poisoning was finished. It was shown that chronic CCl4 poisoning induced a typical liver cirrhosis accompanied with the 2-3 times increase in the total glycogen content, in comparison with the norm, with the decrease in LF to 53%, and also with the fall of G-6-Pase and GP activities by 82 and 25%, resp. After 1, 3 and 6 months following poisoning cessation, the lobule structure, infringed due to cirrhosis, was not restored. But functional parameters of the cirrhotic liver were seen gradually recovering without CCl4 poisoning. The application of carbohydrate rich diet favoured a most complete rehabilitation: the content of total glycogen and its fractions and the activity of G-6-Pase and GP returned to the normal level.

Epidermal growth factor protects against carbon tetrachloride-induced hepatic injury

1. Epidermal growth factor (EGF) is known to protect the gastrointestinal tract against various noxious agents. Its potential value in preventing/ treating hepatic injury is, however, largely unexplored. We therefore examined whether EGF could influence CCl4-induced hepatic injury. 2. Female Sprague-Dawley rats (8 per group) received saline or recombinant EGF (500 or 750 micrograms/kg, intraperitoneal) 30 min before CCl4 (20% v/v, in olive oil, intraperitoneal). Eighteen hours later, animals were killed, serum was collected for assay of biochemical markers of hepatic injury and livers were removed for histological analyses. 3. Administration of CCl4 resulted in severe hepatic necrosis and caused a 10-fold rise in plasma alanine aminotransferase levels compared with levels seen in control animals (218 +/- 15 compared with 23 +/- 9 mumol/l in controls, mean +/- SEM, P < 0.01). Serum malondialdehyde levels, used as a marker of lipid peroxidation, showed a 2-fold rise in response to CCl4 treatment (median 4.0, quartile range 3.3-5.8 units/l compared with median 2.3, quartile range 2.1-2.5 units/l in controls, P < 0.05). Administration of EGF at 500 micrograms/kg, before the CCl4, did not protect against injury, as assessed by histology or rise in plasma alanine aminotransferase levels. In contrast, animals given EGF at 750 micrograms/kg, before the CCl4, had only minimal changes in histology, with only a minor rise in alanine aminotransferase levels (37 +/- 4 compared with 23 +/- 9 mumol/l in animals not given CCl4) and had no significant rise in malondialdehyde levels. 4. EGF protects against CCl4-induced hepatic injury and may provide a novel approach to the treatment of liver damage.