The antioxidant activity of chondroitin-4-sulphate, in carbon tetrachloride-induced acute hepatitis in mice, involves NF-kappaB and caspase activation

BACKGROUND AND PURPOSE

Reactive oxygen species (ROC) are the main causes of carbon tetrachloride (CCl4)-induced acute liver injury. Chondroitin-4-sulphate (C4S) is known to inhibit lipid peroxidation through antioxidant mechanisms. Activation of nuclear factor (NF)-kappaB and caspases may strongly intensify inflammation and cell damage, in addition to that directly exerted by ROS. We investigated whether treatment with C4S, besides exerting antioxidant activity, was able to modulate NF-kappaB and apoptosis activation in CCl4-induced liver injury in mice.

EXPERIMENTAL APPROACH

Acute hepatitis was induced in mice by an i.p. injection of CCl(4). Varying doses of C4S were administered i.p. 1 h before, 6 and 12 h after CCl4 injection. 24 h after CCl4 injection, the mice were killed for biochemical and histological analysis.

KEY RESULTS

CCl4 injection produced: marked elevation of alanine aminotransferase and aspartate aminotransferase; hepatic membrane lipid peroxidation, assayed by 8-isoprostane levels; and depletion of reduced glutathione and superoxide dismutase. CCl4 also decreased NF-kappaB translocation and IkBalpha, and increased gene expression of mRNA and protein of metalloproteases (MMP)-2 and -9, and of pro- and cleaved forms of caspases-3 and -7. There was also increased liver polymorphonuclear infiltration, evaluated by elastase assay, and hepatic cell disruption.C4S treatment inhibited lipid peroxidation; blocked NF-kappaB activation and IkBalpha protein loss; decreased mRNA and proteins for MMPs and caspases; restored endogenous antioxidants; limited hepatic polymorphonuclear accumulation and tissue damage.

CONCLUSIONS AND IMPLICATIONS

As antioxidants may inhibit NF-kappaB and caspase activation, we hypothesize that treatment with C4S was able to inhibit NF-kappaB and apoptosis activation in hepatic injury.

Portulene, a new diterpene from Portulaca oleracea L

Chromatographic fractionation of the chloroform extract of Portulaca oleracea L. growing in Egypt afforded a new clerodene diterpene portulene (1), in addition to the known compounds lupeol (2), beta-sitosterol (3), and daucosterol (4), which were reported for the first time from the title plant. The structures of the isolated compounds were unambiguously established through 1D, 2D, and mass spectral analyses. Co-treatment of CCl(4) hepatic injured rats with 70% alcohol extract of P. oleracea significantly restored the hepatic marker enzymes and total bilirubin to near-normal values, which demonstrated hepatoprotective activity. In addition, the P. oleracea extract showed antibacterial and antifungal activities.

[Curative effect of interferon-alpha on rat liver fibrosis induced by CCl4]

OBJECTIVE

To explore the curative effect and the mechanism of interferon-alpha (IFN-alpha) on rat liver fibrosis induced by CCl4.

METHODS

Thirty-nine male SD rats were randomly divided into 3 groups. The rats in the normal control group (n=10) received subcutaneous injection of peanut oil (0.003 mL/g body weight) for 10 weeks. Rat liver fibrosis was induced in 29 rats by 0.003 mL/g subcutaneous injection of 40% CCl4 (CCl4: peanut oil = 2:3), twice weekly for 10 weeks. In the 7th week, these 29 rats were randomly divided into a liver fibrosis group without treatment (n=15) and an IFN-alpha treatment group (n=14), which received subcutaneous injection of IFN-alpha-2b at 10(6) units per rat. The rats' liver tissue was collected and HE and Masson staining were performed to observe of pathological changes, stage of liver fibrosis,and semi-quantitative scoring. Immunohistochemistry was used to detect the expression of Collagen I, alpha-smooth muscle actin (alpha-SMA),and transforming growth factor-beta1 (TGF-beta1) in the rat liver.

RESULTS

The stage of liver fibrosis, semi-quantitative scoring of Masson staining, and immunohistochemical staining of Collagen I in the liver fibrosis group were significantly higher than those of the normal controls (All P<0.01), and those in the IFN-alpha treatment group were significantly lower than those of the liver fibrosis group(P<0.05). The semi-quantitative immunohistochemical scoring of alpha-SMA and TGF-beta1 in the liver fibrosis group was significantly higher than those of the normal control (All P<0.01), and that in the IFN-alpha treatment group was significantly lower than that of the liver fibrosis group (All P<0.05).

CONCLUSION

Treatment of IFN-alpha can decrease the liver fibrogenesis induced by CCl4 in rats. The anti-fibrosis effect of IFN-alpha may be attributed to the inhibition of the hepatic stellate cells' activation to decrease TGF-beta1 expression.

[Research on active part of Sambucus chinensis against hepatitis mice induced by CCl4]

OBJECTIVE

To investigate the best extraction process of Sambucus chinensis against hepatitis and research on its active part.

METHODS

We studied the protective effects of different extracts of Sambucus chinensis distilled by different extraction process on mice acute hepatic injury induced by CCl4, and searched for the active part of Sambucus chinensis against hepatitis from the best extract by extraction with different solvent and purification with macroporous adsorption resin, then studied their protective effects on mice acute hepatic injury induced by CCl4.

RESULTS

The extraction of Sambucus chinensis by 75% alcohol showed very significantly protective effects on mice acute hepatic injury induced by CCl4 and the effects were better than that of other extraction process. The extraction eluted by 30% alcohol after purification with macroporous adsorption resin and extracted by EtOAc in the extraction of Sambucus chinensis by 75% alcohol all showed significantly protective effects on mice acute hepatic injury induced by CCl4, and the effects of the extraction eluted by 30% alcohol after purification with macroporous adsoption resin were better than extraction with EtOAc.

CONCLUSIONS

The best extraction solvent is 75% alcohol. The active part of Sambucus chinensis against hepatitis is the extraction eluted by 30% alcohol after purification with macroporous adsorption resin and extraction with EtOAc.

[Akt gene therapy for cirrhotic rats with portal hypertension]

OBJECTIVE

To determine whether there is an impaired Akt and eNOS activation in cirrhotic livers, and to investigate the feasibility of transferring adenovirus-mediated Akt gene to the liver for portal hypertension.

METHODS

Recombinant adenovirus Ad-myr-HA-Akt and Ad-EGFP were produced by homologoas recombination in 293 cells . The Methods of compound factor, carbon tetrachloride (CCl4), corn flour, and cholesterol plus alcohol were used to construct the hepatic cirrhosis rat models. Ten normal rats were served as a normal control group, and 40 cirrhotic rats were divided into 4 groups randomly: an untreated group, an Ad-myr-HA-Akt treated group, an Ad-EGFP group, and a saline group. Ad-myr-HA-Akt, Ad-EGFP, and saline were transduced into the Ad-myr-HA-Akt treated group, Ad-EGFP group, and saline group via the tail vein respectively. Portal vein pressure, mean arterial pressure, and heart rate were measured in all rats. Protein abundance and phosphorylation status of Akt and eNOS were examined by Western blot. Spectrophotometry was used to measure the NO level. Frozen sections of the liver, heart, lung, kidney, brain, spleen, and testis were made to examine the expression of enhanced green fluorescent protein (EGFP) by fluorescence microscopy on Day 3 in the Ad-EGFP group.

RESULTS

The concentration of recombinant adenovirus Ad-myr-HA-Akt after the purification was 5.5 x 10(11)vp/mL and that of Ad-EGFP was 6.0 x 10(11)vp/mL. Akt and eNOS phosphorylations in the liver of cirrhotic rats were obviously impaired. Adenoviral delivery of myr-Akt restored eNOS phosphorylation, increased the NO level and decreased the portal pressure after 3 days of adenoviral infection. In contrast, the livers infected with Ad-EGFP and saline were not changed. The EGFP expression was mainly found under the fluorescence microscopy on the frozen section of liver. Very little fluorescence was detected in the lung and kidney; and there was no detectable EGFP in other organs.

CONCLUSION

There is an impaired Akt and eNOS activation in the cirrhotic livers; myr-Akt gene therapy can restore the Akt activation and NO production in the cirrhotic liver, suggesting that this therapy may be helpful in treating portal hypertension.

One-day dietary restriction changes hepatic metabolism and potentiates the hepatotoxicity of carbon tetrachloride and chloroform in rats

Although dietary restriction (DR) is common in modern society, research about hepatic metabolism and the hepatotoxicity induced by DR has been conducted less intensively than that induced by fasting. In the present study, we fed male Wistar rats at five levels of food intake for one day, including conventional feeding (60 kcal), three of DR (45, 30, and 15 kcal), and fasting (0 kcal), and observed the metabolic changes of hepatic cytochrome P450 2E1(CYP2E1) and the hepatotoxicity of chloroform (CHCl(3)) and carbon tetrachloride (CCl(4)). The CYP2E1 content was significantly increased in 15 kcal-food and fasting groups. The hepatic glutathione (GSH) content, which protects the liver from hepatotoxic agents, was depleted in 15 kcal-food and fasting groups. After the challenge by CHCl(3) and CCl(4), the activities of aspartate aminotransferase and alanine aminotransferase, marker enzymes for liver damage, were elevated remarkably at all food groups. Moreover, their activities increased significantly in DR groups, in comparison to the corresponding 60 kcal-food group. After the challenge, the hepatic GSH content was also depleted significantly in 15 kcal-food and fasting groups. CHCl(3) was cleared by hepatic metabolism about 8-10 times faster than that of CCl(4). Similarly, the areas under the blood concentration-time curve of CCl(4) was as much as twice that of the corresponding CHCl(3). In conclusion, when food was restricted to less than half of conventional amount, hepatic metabolism was affected and the hepatotoxicity induced by CCl(4) or CHCl(3) was augmented by, at least in part, CYP2E1 induction and GSH depletion.

Prevention of liver fibrosis by the purinoceptor antagonist pyridoxal-phosphate-6-azophenyl-2',4'-disulfonate (PPADS)

BACKGROUND

Hepatic stellate cells (HSC) are important mediators of liver fibrosis. HSC express purinergic receptors for extracellular ATP that induce fibrogenesis. Pyridoxal-phosphate-6-azophenyl-2', 4'-disulfonate (PPADS) is a highly bioavailable purinoceptor inhibitor. We sought to determine whether PPADS could prevent experimental liver fibrosis in rats.

MATERIALS AND METHODS

The effect of PPADS as an inhibitor of HSC purinoceptors was compared to the effect of suramin using confocal video microscopy. Rats were treated with CCl4, dimethylnitrosamine, or common bile duct ligation in the presence or absence of PPADS. Fibrosis in liver sections was assessed using Trichrome and Sirius red stains. In HSC isolated from experimental animals, proliferation was determined by bromodeoxyuridine uptake, apoptosis was determined using Annexin V flow cytometry, and transcription of alpha(1)-procollagen and fibronectin were determined using quantitative RT-PCR.

RESULTS

Both PPADS and suramin inhibited HSC purinoceptor activation, but PPADS had a more durable effect. PPADS completely blocked the development of cirrhosis due to CCl4 or dimethylnitrosamine but not due to bile duct ligation. PPADS inhibited HSC proliferation, but had no effect on HSC apoptosis. PPADS inhibited transcription of alpha(1)-procollagen and fibronectin by HSC.

CONCLUSION

Blockade of purinergic receptors is a novel approach to prevention of non- biliary liver fibrosis. The primary action of PPADS is to inhibit HSC proliferation and fibrogenesis. Future design of purinergic receptor inhibitors may be an effective pharmacologic treatment to prevent liver fibrosis.

[Synthesis of metabolites of bicyclol]

Bicyclol is a new generation of anti-hepatitis drug with China's own intellectual property rights. The chemical structure of bicyclol is new and original. Pharmacological research showed that it has high clinical efficacy in treating chronic hepatitis (HBV) patients and lower side effects. Two metabolites of bicyclol have been isolated: M2 (4-hydroxy-4'-methoxy-5, 6, 5', 6'-bis (methylenedioxy)-2-hydroxylmethyl-2'-methoxycarbonyl biphenyl) and M3 (4'-hydroxy-4-methoxy-5, 6, 5', 6'-bis (methyl enedioxy)-2-hydroxylmethyl-2'-methoxycarbonyl biphenyl). To further study the mechanism, safety, and effectiveness of bicyclol, the M2 and M3 have been total synthesized. The synthesis route is as following: the carboxyl and phenolic hydroxyl group of the aromatic bromide had been separately protected by bromobenzyl, coupling through the intermolecular asymmetric Ullmann reaction and then catalyst hydrogenated, borane reducted, two metabolites of bicyclol M2 and M3 were obtained. The structures were determined by IR, 1H NMR, HRMS. Comparison of hepatoprotective activity of bicyclol and the two metabolites on experimental liver injury, the potency of the metabolites were lower than that of bicyclol.

Hepatoprotective Properties of Bauhinia variegata Bark Extract

Bauhinia variegata (Leguminosae) commonly known as Kachnar, is widely used in Ayurveda as tonic to the liver. The present work was carried out to assess the potential of Bauhinia variegata bark as hepatoprotective agent. The hepatoprotective activity was investigated in carbon tetrachloride (CCl(4)) intoxicated Sprague-Dawley rats. Bauhinia variegata alcoholic Stem Bark Extract (SBE) at different doses (100 and 200 mg/kg) were administered orally to male Sprague-Dawley rats weighing between 100-120 g. The effect of SBE on the serum marker enzymes, viz., AST, ALT, ALP and GGT and liver protein and lipids were assessed. The extract exhibited significant hepatoprotective activity. Hence, B. variegata appears to be a promising hepatoprotective agent.

Antifibrotic activity of rofecoxib in vivo is associated with reduced portal hypertension in rats with carbon tetrachloride-induced liver injury

BACKGROUND AND AIM

Upregulation of cyclooxygenase-2 (COX-2), an inducible enzyme that is actively involved in inflammation and wound healing, has been found in cirrhotic livers. The aim of this study was to investigate the effects of selective inhibition of COX-2 on the development of liver cirrhosis and portal hypertension in rats.

METHODS

Liver cirrhosis was induced by carbon tetrachloride (CCl(4)) in Sprague-Dawley rats. Rofecoxib, a highly selective COX-2 inhibitor, was orally administered to rats at a dose of 10 mg/kg/day. Portal pressure was measured at 8 weeks post CCl(4) administration with the catheterization method followed by the harvesting of liver samples. Liver histopathology was analyzed with hematoxylin and eosin and Masson's trichrome staining. The activated, alpha smooth muscle actin (alpha-SMA) positive hepatic stellate cells (HSCs) and the protein levels of collagen types I, III, IV, as well as laminin and two fibrogenic mediators, vascular endothelial growth factor (VEGF) and connective tissue growth factor (CTGF) in the livers, were detected with immunohistochemical staining and western blot methods, respectively. The level of hepatic thromboxane B(2) (TXB(2)), a potent vasoconstrictive substance derived from COX, was measured with enzyme immunoassay.

RESULTS

Oral administration of rofecoxib decreased portal pressure in rats that were treated with CCl(4) for 8 weeks. This was associated with a marked reduction in collagen accumulation and TXB(2) level in the rat livers. In addition, rofecoxib administration was found to reduce the number of activated HSCs and to downregulate hepatic protein levels of three detected types of collagen, laminin, VEGF and CTGF in CCl(4)-treated rats.

CONCLUSIONS

COX-2 is involved in the fibrogenesis of livers and the formation of portal hypertension in CCl(4)-treated rats. Selective inhibition of COX-2 by rofecoxib reduces portal hypertension and this is associated with antifibrotic activity as well as a reduction of COX-2-derived vasoactive substance.

Expression of Toll-like receptor 4 in rat liver during the course of carbon tetrachloride-induced liver injury

BACKGROUND AND AIM

It has recently been reported that Toll-like receptor 4 (TLR4) is involved in cellular responses to lipopolysaccharides (LPS) and early liver injury induced by LPS. The aim of the present study was to investigate the alterations of TLR4 gene expression in liver tissues and Kupffer cells during the course of carbon tetrachloride (CCl(4))-induced chronic liver injury and fibrosis and its role in liver injury.

METHODS

Rats were induced with liver injury and fibrosis by CCl(4) administered subcutaneously twice weekly for up to 8 weeks. The Kupffer cells were isolated by the combined collagenase-pronase perfusion method and incubated with varying doses of LPS. The mRNA expression of TLR4 in liver tissues and Kupffer cells was measured by reverse transcriptase polymerase chain reaction. The levels of tumor necrosis factor (TNF)-alpha in Kupffer cell culture supernatants were determined by enzyme-linked immunosorbent assay. The plasma levels of the endotoxin were determined by chromogenic substrate limulus amebocyte lysate assay. The association of the endotoxin receptor expression with plasma endotoxin levels was assessed.

RESULTS

CCl(4) administration elicited extensive changes in liver morphology, including steatosis, inflammation, necrosis, and fibrosis. Low levels of TLR4 mRNA were detected in normal rat liver tissues, but no expression was detected in the Kupffer cells. The expression of TLR4 mRNA in liver tissues and Kupffer cells was increased 2 weeks after CCl(4) administration, peaked at 4 and 6 weeks, and declined at 8 weeks. Basic TNF-alpha production of Kupffer cells isolated from CCl(4)-treated rats at 4 and 6 weeks was significantly higher than that of normal rats (P < 0.05). Upon LPS stimulation, production of TNF-alpha was markedly increased in Kupffer cells isolated from normal and 2-,4-, and 6-week CCl(4)-treated rats. Moreover, LPS-induced TNF-alpha production was dose-dependent. The plasma levels of the endotoxin were increased during the time of liver injury. There was a correlation between plasma endotoxin levels and TLR4 gene expression in the early and middle stage of liver injury.

CONCLUSION

The gene expression of TLR4 was upregulated during the course of CCl(4)-induced liver injury, which is associated with the degree of liver injury and Kupffer cell activation. The gut-derived endotoxin may be involved in the upregulation of TLR4 expression.

[Experimental study of two histological quantitative methods of hepatic fibrosis]

To evaluate the value of two histological quantitative methods of hepatic fibrosis: semiquantative scoring system (SSS) and image analysis by computer. The prophylactic and therapeutic effect of Ganzhifu on hepatic fibrosis induced by CCl4 were studied on a total 73 of specimens from liver tissue of rats. All specimen were analyzed quantatively by two methods of SSS marks and image analysis respectively. Difference between groups was compared and hydroxyproline (Hyp) content of each liver tissue was examined. Correlation analysis was done between SSS marks, image analysis and Hyp content. Both prophylactic and therapeutic study showed the same information. Results of SSS marks, image analysis and Hyp content were coincidence. It suggest that both SSS marks and image analysis were interrelated well with Hyp content (P < 0.01). The result suggests that both SSS marks of hepatic fibrosis and image analysis by computer can be taken as reliable histological quantitative method of hepatic fibrosis.

Antioxidant and protective effect of an oleanolic acid-enriched extract of A. deliciosa root on carbon tetrachloride induced rat liver injury

The ethanol-water extract of A. deliciosa root (EEAD) was fractionated into n-hexane (EEAD-He), ethyl acetate (EEAD-Ea), n-butanol (EEAD-Bu) and aqueous (EEAD-Aq) fractions according to their different polarity and solubility. Among the four extracts, it was found that EEAD-Bu was enriched with oleanolic acid (OLA). The antioxidant and hepatoprotective activities of various EEAD fractions and OLA were carefully investigated by the methods of ferric thiocyanate (FTC) and thiobarbituric acid (TBA), as well as the model of CCL4-induced liver toxicity in rats. The results showed that the EEAD-Bu had higher in vitro antioxidant and in vivo hepatoprotective activities than those of the other types of extracts (p< 0.05). When the CCL4-induced rats were treatment with 120 mg/kg EEAD-Bu, the activities of alanine transaminase (ALT) and aspartate transanimase (AST) in rat serum decreased 90 % and 81 %, respectively, as compared with those of the CCL4 control rats. Furthermore, the lipid peroxidation (MDA) decreased 42 % and glutathione (GSH) increased 114 % in the rats liver homogenate, as compared with those of the control. The results also indicated that the hepatoprotective activity of the EEAD-Bu (at the dose of 120 mg/kg) was higher than that of the reference drug silymarin (at the dose of 60 mg/kg), and OLA acted as an important role in dose-dependent protection against CCL4 hepatotoxicity. The findings indicate that the OLA-enriched EEAD-Bu extract had significant and concentration dependent hepatoprotective effect for the carbon tetrachloride induced rat liver injury.

[Protective effect of heme oxygenase-1 and its reaction product, carbon monoxide on acute liver injury induced by carbon tetrachloride in rats]

OBJECTIVE

To investigate the protective role of heme oxygenase-1 and its reaction product, carbon monoxide against acute liver injury induced by carbon tetrachloride in rats.

METHODS

Thirty male Sprague-Dawley rats were randomly divided into six groups with five in each. The control group received a single dose of corn oil injection. Carbon tetrachloride was injected intraperitoneally (i.p) to establish acute liver injury models in rats. Hemin(50 micromol/kg) was administered i.p. 12 hours before CCl(4) treatment, with an aim to induce HO-1 protein expression in the liver of rats. Carbon monoxide was injected i.p. 12 hours prior to CCl(4) injection, resulting in about 8%-12% carboxyhemoglobin concentration in vivo. The expression of HO-1 in the liver of hemin-treated rats was determined by western blot method at different time points. At 24 h after carbon tetrachloride administration, all rats were sacrificed to collect blood samples for the examination of ALT, AST levels and to remove liver tissues for analysis of MDA concentration, SOD activity and caspase-3 activity as well as TNF-alpha contents. In addition, histopathological changes were investigated and hepatocyte apoptosis was detected by TUNEL method.

RESULTS

The administration of carbon tetrachloride to rats caused a marked hepatic damage, characterized by significant elevation of serum ALT, AST levels(2 136.3+/-163.4 U, 1 422.7+/-221.7 U) and liver MDA content(5.28+/-0.93 micromol/g), caspase-3 activity (optical density value 4.69+/-1.02) and TNF-alpha level(256.3+/-27.3 ng/L) combined with a remarkable reduction in liver SOD activity (45.9+/-14.8 U/mg) as compared with the control rats. Histopathological observations revealed severe damage in the liver and prominent hepatocyte apoptosis took place in CCl(4) -treated rats. However, pretreatment with hemin could induce high expression of HO-1 protein and exert potent protective effects against liver injury, as demonstrated by a significant decrease in ALT, AST levels(287.1+/-24.3 U, 246.2+/- 21.7 U) and MDA concentration(3.27+/-1.34 micromol/g), reduction in caspase-3 activity(optical density value 2.49+/-1.47) and TNF-alpha level(132.6+/-19.5 ng/L), as compared with the CCl(4) -treated rats. Moreover, hepatocyte apoptosis and liver injury were both attenuated remarkably in the liver of rats pretreated with hemin. In contrast to hemin administration, single injection of exogenous CO produced the same protective effects, as indicated by the remarkable reduction of ALT, AST levels and caspase-3 activity and TNF-alpha levels.

CONCLUSION

The above results suggest that HO-1/CO system has a potent protective effect on acute liver injury induced by carbon tetrachloride in rats. Induction of HO-1 expression and low concentration of CO can inhibit the progress of hepatic damage, which might be due to the alleviation of lipid peroxidation and reduction of caspase-3 activity or inhibition of TNF-alpha level.

Evaluation of cirrhotic liver with perfusion-weighted magnetic resonance imaging: a preliminary experimental study in animal models with half-liver cirrhosis

OBJECTIVE

To investigate the role of perfusion-weighted magnetic resonance imaging (MRI) in evaluation of cirrhotic liver.

METHODS

With a 4F catheter, 1% diluted carbon tetrachloride (1 ml/kg) was selectively injected into right or left hepatic artery of 12 dogs fortnightly. The half liver into which carbon tetrachloride was injected was called as study side (SS), while the other half liver without carbon tetrachloride injection was called as study control side (SCS). Conventional and perfusion-weighted MRI were performed in every 4 weeks. Via a 4F catheter, 5ml gadolinium diethylentriamine pentaaceti acid (Gd-DTPA) dilution was injected into superior mesenteric artery at the 5th scan. The signal intensity-time curves of SS, SCS, and portal vein were completed in MR workstation. The maximal relative signal increase (MRSI), peak time (tp), and slope of the curves were measured.

RESULTS

On conventional MR images, no abnormalities of externality and signal intensity were observed in both SS and SCS of liver at each stage. The mean tp, MRSI, and slope of intensity-time curves in normal liver were 10.56 seconds, 1.01, and 10.23 arbitrary unit (au)/s, respectively. Three parameters of curves didn't show obvious change in SCS of liver at every stage. Abnormal perfusion curves occurred in SS of liver at the 12th week after the 1st injection. The abnormality of perfusion curve in SS was more and more serious as the times of injection increased. The mean tp, MRSI, and slope intensity-time curves in SS of liver were 19.45 seconds, 0.43, and 3.60 au/s respectively at the 24th week.

CONCLUSION

Perfusion-weighted imaging can potentially provide information about portal perfusion of hepatic parenchyma, and to some degree, reflect the severity of cirrhosis.

Effect of β-alanine administration on carbon tetrachloride-induced acute hepatotoxicity

Mice were supplemented with beta-alanine (3%) in drinking water for one week. beta-Alanine intake reduced hepatic taurine levels, but elevated cysteine levels significantly. Hepatotoxicity of CCl4 in mice fed with beta-alanine was decreased as determined by changes in serum enzyme activities. Hepatic glutathione and taurine concentrations after CCl4 challenge were increased markedly by beta-alanine intake. The enhanced availability of cysteine for synthesis of glutathione and/or taurine appears to account for the hepatoprotective effects of beta-alanine against CCl4-induced liver injury.

[Effects and mechanisms of shaoqiduogan on mice with chemical liver injury]

OBJECTIVE

To study the therapeutic effects and mechanisms of SQDG on carbon tetrachloride-induced chemical liver injury in mice as well as its possible mechanisms. At the same time the pharmacodynamics of SQDG was compared with TGP or ASTs of effective dose.

METHOD

The model of carbon tetrachloride-induced chemical liver injury in mice was prepared. The levels of ALT, AST, MDA content, SOD and GSH-Px activities in liver homogenate were assayed by spectrophotometry; Meanwhile, hepatic pathological examination was observed.

RESULT

Protective effect of SQDG on carbon tetrachloride-induced chemical liver injury: SQDG was able to significantly decrease serum transaminase levels of chemical liver injury's mice induced by carbon tetrachloride, decreased MDA content and improved the reduced SOD and GSH-px levels in liver homogenate. Furthermore, SQDG also attenuate the area and extent of necrosis and reduce the infiltration of inflammatory cell. Compared with TGP or ASTs of effective dose, SQDG has a better effect on carbon tetrachloride-induced chemical liver injury in mice.

CONCLUSION

SQDG can protect mice injured by carbon tetrachloride-induced chemical.

[Protecting effect of brevifolin and 8,9-single-epoxy brevifolin of Phyllanthus simplex on rat liver injury]

OBJECTIVE

To investigate the effect of protecting liver of brevifolin and 8,9-single-epoxy brevifolin of Phyllanthus simplex.

METHOD

Rats were administered with CCl4 (ip) or alcohol (ig) to establish acute or chronic liver injured model, respectively. ALT, AST and TBIL in serum were measured using colorimetric analysis to evaluate liver function. MDA content or SOD activity in serum and liver tissue was measured by thiobarbituric acid chromatometry and xanthine oxidase methods, respectively. The hemorheological parameters were observed.

RESULT

Brevifolin and 8,9-single-epoxy brevifolin reduced the increase of ALT induced by CCl4, but they did not influence the increase of AST. And it could inhibit the pathologic increase of serum TBIL induced by alcohol. They could ameliorate the MDA increase or SOD decrease in serum and liver tissue in rats with liver injury, and decrease abnormal changed hemorheological parameters.

CONCLUSION

Brevifolin and 8,9-single-epoxy brevifolin show protective effective against acute and chronic liver injuries, and the mechanism is relevant to antagonizing the lipid peroxidation of free radical and improving the blood circulation.

Hepatoprotective effects of Pittosporum neelgherrense Wight&Arn., a popular Indian ethnomedicine

The stem bark of Pittosporum neelgherrense Wight&Arn. is used by the Kani and Malapandaram tribes of Kerala as an effective antidote to snake bite and for the treatment of various hepatic disorders. In the present study, the effect of the methanolic extract of the stem bark of Pittosporum neelgherrense was studied against carbon tetrachloride (CCl(4))-, d-galactosamine (D-GalN)- and acetaminophen (APAP)-induced acute hepatotoxicity in Wistar rats. Significant hepatoprotective effects were obtained against liver damage induced by all the three liver toxins, as evident from decreased levels of serum enzymes, glutamate oxaloacetate transaminase (SGOT), glutamate pyruvate transaminase (SGPT) and an almost normal architecture of the liver in the treated groups, compared to the toxin controls. Thus the present study provides a scientific rationale for the traditional use of this plant in the management of liver diseases.

[Change of zero-stress state of portal vein in the rat during the pathogenesis of intrahepatic portal hypertension]

A model of intrahepatic portal hypertension was established in SD rats by injection of carbon tetrachloride (CCl4). By observing the opening angle of the portal vein, the zero-stress state of the portal veins was studied at different time during the pathogenesis of intrahepatic portal hypertension. After CCl4 injection, the opening angles of the portal veins were increased, in the tenth week, they were much greater than those in the corresponding controls (P<0.05). The results suggest that during the pathogenesis of portal hypertension, unequal remodeling exists in the portal veins to change its biomechanical properties, and the residual stress and strain of the portal veins in portal hypertensive rats are greater than those in normal controls.