Prophylactic effect of tritoqualine (TRQ) on the CCl4-induced chronic liver injury model in rats

Tritoqualine (TRQ) administered at doses of 100 or 200 mg/kg, perorally, had a preventive effect on the liver injury in rats induced by the treatment with CCl4 for 12 weeks consecutively. Rats subjected to this chronic treatment with CCl4 showed a decrease in body weight gain and changes in several serum parameters that are indicators of hepatic function were observed: the increase of transaminases, as a parameter of hepatocyte breakdown; the increase of alkaline phosphatase, as a parameter of biliary system abnormalities, the reduction of prothrombin time, as a marker of protein biosynthesis in the liver; and the change of lipids concentrations, reflecting liver injury. After the administration of TRQ perorally, there was a notable suppression of the increment in leaked enzymes in the serum and a marked improvement of the parameters concerning protein biosynthesis and lipid metabolism in comparison with CCl4 control rats. Marked fibrosis in the liver was observed after CCl4 treatment for 12 weeks, and the collagen content in the liver was 5 times higher than that of control rats. TRQ suppressed the increment in collagen formation and also showed improvement of the decrease of the liver function with regards to protein biosynthesis in CCl4-treated rats. Judging from these results, it was concluded that TRQ had a remarkable protecting action on the liver injury chronically induced by CCl4 treatment and was a effective compound for restoring liver function.     

Suppressive effect of tritoqualine (TRQ) on the acceleration of fibrosis in the liver

Liver cirrhosis was induced by consecutive CCl4-treatment of rats (0.5 ml/kg, s.c., 2 times/week) to investigate the effect of TRQ on the acceleration of fibrosis in the liver. An increase of hydroxyproline content in the liver of rats began 12 weeks after the CCl4 treatment and a 1.9-fold increase was observed at week 14 compared with non-CCl4 treated rats. Histamine in the liver increased about 2 times at week 14. Increased numbers of mast cells were seen in the area of proliferated collagen fiber in the liver under microscopic observation, and also a good correlation was recognized between the number of mast cells and the progression of fibrosis. An administration of TRQ to the rats for 2 weeks from week 13 resulted in significant suppression of both the increase in hydroxyproline and histamine in the liver dose-dependently compared with the CCl4 control group. Both progression of collagen and increase in mast cell numbers were also suppressed by TRQ dose-dependently under histopathological observation; at the same time the decrease in mast cells was recognized to correspond to the decrease in hydroxyproline and histamine in the liver. Thus, it was suggested that increased mast cells participated in the biosynthesis of collagen. Though the elevated serum transaminases, alkaline phosphatase and leucine amino peptidase were also suppressed by TRQ administration, the protein biosynthesis activity of the liver and lowered serum total cholesterol were not improved as much as the other parameters. From these results, it was shown that TRQ was especially and remarkably effective in suppressing the acceleration of fibrosis, and one of the pharmacological mechanisms of this action may be ascribed to the inhibitory effect of TRQ on the activation of mast cells by some stimulants.     

Effect of tritoqualine on liver regeneration after partial hepatectomy in rats

Effect of tritoqualine (TRQ) on liver regeneration after partial hepatectomy in normal rats and chronically injured rats treated with carbon tetrachloride (CCl4) for 12 weeks were investigated by the measurement of serum and liver biochemical parameters concerning the hepatic function. The results are as follows: 1) In normal rats, the liver regeneration rate after partial hepatectomy was increased dose-dependently with the administration of TRQ for 7 days after the operation. TRQ improved BSP retention rate which was decreased after partial hepatectomy. In addition, protein synthetic activity in the liver microsomes prepared from TRQ-administered rats was higher than that prepared from control rats, and the contents of serum total protein, serum albumin and liver protein were also higher in TRQ-administered rats. 2) In the rats treated with CCl4 for 12 weeks, the liver regeneration rate after partial hepatectomy was increased dose-dependently with the administration of TRQ for 6 days. TRQ also improved the contents of serum total protein, serum albumin and liver protein. Though the amount of collagen in the liver chronically injured by CCl4 increased more than twice compared with that in the normal liver, the amount of collagen in the regenerating liver of CCl4-treated rats whose liver regeneration was accelerated by TRQ was not different from that in the normal liver. These results suggest that TRQ has the effect of improving the various hepatic functions through the activation of the protein synthesis in hepatocytes.     

Effects of TJN-101, a lignan compound isolated from Schisandra fruits, on liver fibrosis and on liver regeneration after partial hepatectomy in rats with chronic liver injury induced by CCl4

TJN-101 ((+)-(6S,7S,R-biar)-5,6,7,8-tetrahydro-1,2,3,12-tetramethoxy -6,7-dimethyl-10,11-methylenedioxy-6-dibenzo[a,c]cyclooctenol) is one of the lignan compounds isolated from Schisandra fruits. 1) Effect of TJN-101 on liver fibrosis was investigated in rats which were injected with CCl4 (1 ml/kg) subcutaneously twice a week for 12 weeks. TJN-101 was given orally at the dose of 10 or 30 mg/kg/day for 6 or 3 weeks beginning on the 6th or 9th week after the start of CCl4-intoxication, respectively. The elevations of serum transaminase activities and the increase of liver 4-hydroxyproline content were observed depending on the period of CCl4-intoxication. These changes were marked on the 9th and 12th weeks after. In the histopathological study, the degenerative fatty change on the 6th week after and the formation of pseudolobule caused by fibrosis proliferation on the 9th or 12th week after were mainly observed. When rats were treated with TJN-101, the abnormalities in biochemical parameters and the fibrosis proliferation caused by CCl4-intoxication were improved. 2) Chronic liver injury was induced by the treatment with CCl4 (1 ml/kg) subcutaneously twice a week for 10 weeks to investigate the effect of TJN-101 on liver regeneration after partial hepatectomy. TJN-101, which was given orally at the dose of 10, 30 or 100 mg/kg/day for 6 days from the 1st day after partial hepatectomy, dose-dependently increased the liver regeneration rate and improved the serum BSP retention rate. These results suggest that TJN-101 suppresses the fibrosis proliferation and accelerates both the liver regeneration and the recovery of liver function after partial hepatectomy in chronic liver injury.     

Effects of various methanol extracts of crude drugs on experimental subacute and chronic hepatic injury]

The effects of 5 crude drugs (Myricae Cortex, Polygoni Avicularis Herba, Hyperici Erecti Herba, Forsythiae Fructus, Desmodii Herba) on subacute and chronic hepatic injuries induced by carbon tetrachloride (CCl4) or alpha-naphthylisothiocyanate (ANIT) were investigated in rats. All of these crude drugs suppressed significantly the increase of several biochemical parameters with CCl4-injection twice per week for 4 weeks. Polygoni Avicularis Herba and Desmodii Herba among 5 crude drugs also protected the subacute hepatic injury induced by ANIT-injection for 4 weeks. In addition, the therapeutic effect of Desmodii Herba on the chronic hepatic injury induced by CCl4-injection for 9 weeks was recognized. Desmodii Herba has protective effects on the acute and subacute hepatic injuries induced by CCl4 or ANIT and an improving effect on the chronic injury induced by CCl4. Though the increase of hydroxylproline content in the liver began 4 weeks after the CCl4 or ANIT treatment, every crude drug had no significant effect against the liver fibrosis in these study.     

Protective effects of total flavonoids of Bidens bipinnata L. against carbon tetrachloride-induced liver fibrosis in rats

Bidens bipinnata L. is well known in China as a traditional Chinese medicine and has been used to treat hepatitis in clinics for many years. In a previous study we found that total flavonoids of Bidens bipinnata L. (TFB) had a protective effect against carbon tetrachloride (CCl4)-induced acute liver injury in mice. Now this study was designed to investigate its therapeutic effect against CCl4-induced liver fibrosis in rats and to determine, in part, its mechanism of action. The liver fibrosis model was established by subcutaneous injection of 50% CCl4 twice a week for 18 weeks. TFB (40, 80 and 160 mg kg(-1)) was administered by gastrogavage daily from the 9th week. The results showed that TFB (80 and 160 mg kg(-1)) treatment for 10 weeks significantly reduced the elevated liver index (liver weight/body weight) and spleen index (spleen weight/body weight), elevated levels of serum transaminases (alanine aminotransferase and aspartate aminotransferase), hyaluronic acid, type III procollagen and hepatic hydroxyproline. In addition, TFB markedly inhibited CCl4-induced lipid peroxidation and enhanced the activity of the antioxidant enzymes superoxide dismutase and glutathione peroxidase. Moreover, TFB (80 and 160 mg kg(-1)) treatment improved the morphologic changes of hepatic fibrosis induced by CCl4 and suppressed nuclear factor (NF)-kappaB, alpha-smooth muscle actin (SMA) protein expression and transforming growth factor (TGF)-beta1 gene expression in the liver of liver fibrosis of rats. In conclusion, TFB was able to ameliorate liver injury and protect rats from CCl4-induced liver fibrosis by suppressing oxidative stress. This process may be related to inhibiting the induction of NF-kappaB on hepatic stellate cell activation and the expression of TGF-beta1.     

Isochlorogenic acid A attenuates progression of liver fibrosis through regulating HMGB1/TLR4/NF-κB signaling pathways

OBJECTIVE Liver fibrosis is a chronic damage process related to the further progression of hepatic cirrhosis and has yet no truly effective treatment is available. This study aimed to investigate the effects of isochlorogenic acid A(ICQA) on liver fibrosis induced by carbon tetrachloride(CCl4) and clarify the underlying mechanism. METHODS Rats were treated with CCl4 for eight weeks in order to induce liver fibrosis and simultaneously orally administered with ICQA(10, 20 and 40 mg·kg~(-1)). RESULTS ICQA had significant protective effect on liver injury, inflammation, and fibrosis in rats. Meanwhile, ICQA prevented the activation of hepatic stellate cells(HSC) as indicated by inhibiting the overexpression of a-smooth muscle actin(a-SMA). In addition, reduced fibrosis was found to be associated with decreased protein expression of high-mobility group box 1(HMGB1) and toll like receptor(TLR)4. Moreover, ICQA supressed the cytoplasmic translocation of HMGB1 in rat liver. Further investigations indicated that ICQA treatment significantly attenuated nuclear translocation of the nuclear factor-κB(NF-κB) p65 and inhibited degradation of IkB a expression in the liver of rats with liver fibrosis. CONCLUSION ICQA has hepatoprotective and anti-fibrotic effects in rats with liver fibrosis through modulating the HMGB1/TLR4/NF-κB signaling pathways.     

Inhibitory effect of leflunomide on hepatic fibrosis induced by CCl4 in rats

AIM: To study the effect of leflunomide on CC14-induced hepatic fibrosis in rats. METHODS: Hepatic fibrosis was induced by subcutaneous injection with 50 % CCl4 in Sprague-Dawley rats. The amount of CC14 administered was 1 mg/kg. The alanine aminotransferase (ALT), aspartate aminotransferase (AST), nitric oxide (NO) levels in plasma and hydroxyproline (Hyp) contents in liver tissue were assayed by spectrophotometry. The hyaluronic acid (HA) and procollagen III (PC III) were assessed by radioimmunoassay. The transforming growth factor-β1(TGF-β1) in serum was determined by ELISA. The nuclear factor-kappa B (NF-κB) in liver tissue was examined by immunohistochemistry. Liver samples collected after 12 weeks ofCC14 treatment were stained with hematoxy-lin and eosin. RESULTS: Leflunomide (1, 3, and 9 mg/kg) significantly decreased indices of liver and spleen, the serum transaminase (AST, ALT) activities, HA and PC III levels, and Hyp contents in liver tissue in rats of hepatic fibrosis. Histopathological examination showed leflunomide had inhibitory effect on fibrogenesis and formation of pseudolobulus. Furthermore, leflunomide significantly inhibited NF-κB expression in liver tissue, and reduced elevated serum TGF-κB and NO levels in rats of hepatic fibrosis. CONCLUSION: Leflunomide showed inhibitory action on hepatic fibrosis induced by CC14 in rats.     

Change of hepatic histamine content during hepatic fibrosis

Hepatic function was studied by measuring the time courses of several variables in blood and liver using a chronic liver-injury model produced by administering CCl4 consecutively for 12 weeks in rats. A marked increase in liver histamine content occurred after 10 weeks of treatment with CCl4. At weeks 10 and 12, liver histamine levels in the CCl4-treated group were 1.95 and 4.61 times higher, respectively, than in the control group. This change in liver histamine content appeared after that in other variables such as glutamic pyruvic transaminase, alkaline phosphatase, and white blood cells, but it corresponded to a change in liver hydroxyproline. Increased mast cells were seen in fibrotic foci around Glisson's sheath by microscopic morphological observation of the liver 12 weeks after treatment with CCl4. The histamine concentration in plasma tended to decrease after CCl4 treatment, and at week 12 the decrease was statistically significant compared with control. The liver activities of histamine-metabolizing enzymes, histamine-N-methyltransferase and histaminase, decreased to 1/3.4 and 1/6.0 times those of the nontreated group, respectively, 12 weeks after treatment with CCl4, whereas blood histaminase increased about 9.2 times. The increase in histamine content in injured liver was presumedly derived from the increase in mast cells in the inflamed area of the liver; also, the deficiency of histamine-metabolizing enzymes in liver might have caused the high histamine content in the liver. On the other hand, the decrease in plasma histamine concentration might have occurred as a consequence of the enzyme leakage from hepatocytes that accompanied the breakdown of hepatocytes by CCl4 and thus, of the histamine metabolism in blood by the leaked enzymes. The same kind of experiment was performed using a dimethylnitrosamine-induced liver injury model in rats. The increase of hydroxyproline in the liver occurred 11 days after that of histamine content in liver. These results suggest the possibility that increased histamine in the liver may participate in the biosynthesis of collagen.     

坎地沙坦对肝纤维化大鼠血管紧张素转化酶2表达的影响

目的旨在观察血管紧张素Ⅱ1型受体拮抗剂(ARB)坎地沙坦对四氯化碳(CCl4)大鼠肝纤维化模型的疗效及大鼠肝组织血管紧张素转化酶2(ACE2)表达的影响。方法 42只雄性Wistar大鼠随机分为3组,正常对照组12只,模型组15只,坎地沙坦治疗组15只。除对照组外,给予大鼠首次皮下注射40%CCl4油剂5mL/kg,以后每次皮下注射40%CCL42mL/kg,每周2次。正常对照组给予相同剂量的油剂皮下注射。预防治疗组从实验第1天开始给予坎地沙坦(4mg.kg-1.d-1)灌胃,直至实验结束,共8周。分别于42d(6周)及56d(8周)时,测定各组体质量和门脉压力后,分别杀死6只大鼠,留取血及肝组织标本备用。分离血清测丙氨酸氨基转移酶(ALT),通过苏木素-伊红(HE)及Masson染色观察各组肝纤维化的程度,采用免疫组织化学染色测定ACE2表达情况。结果与对照组相比,模型组体质量降低(P<0.05),血清ALT升高(P<0.05),而预防治疗组体质量增加,ALT水平下降,差异有统计学意义(P<0.05),模型组门脉压力升高,与对照组比较差异有统计学意义(P<0.05),治疗组的门脉压力下降(P<0.05)。ACE2免疫组织化学结果表明:与正常对照组相比,模型组肝组织中ACE2阳性表达增强(P<0.05),坎地沙坦治疗组ACE2表达较模型组明显增高(P<0.05)。结论血管紧张素(Ang)Ⅱ1型受体拮抗剂坎地沙坦具有良好的抗肝纤维化作用,其机制是坎地沙坦可增加肝组织ACE2表达,激活ACE2-Ang-(1-7)-Mas轴,促进Ang-(1-7)的生成增多,从而发挥其抗肝纤维化的作用。     

The protective effects of Hibiscus sabdariffa extract on CCl4-induced liver fibrosis in rats.

Dried flower Hibiscus sabdariffa L. (HSE) extracts, a local soft drink material and medicinal herb, were studied for their protective effects against liver fibrosis induced using carbon tetrachloride (CCl(4)) in rats. Male Wistar rats were administered CCl(4) by intraperitoneal injection for 7weeks and received a normal diet or normal diet with various HSE doses (1-5%) for 9weeks. HSE significantly reduced the liver damage including steatosis and fibrosis in a dose dependent manner. Moreover, HSE significantly decreased the elevation in plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT). It also restored the decrease in glutathione content and inhibited the formation of lipid peroxidative products during CCl(4) treatment. In the primary culture, HSE also significantly inhibited the activation of the hepatic stellate cells. These results suggested that HSE may protect the liver against CCl(4)-induced fibrosis. This protective effect appears due to HSEs antioxidant properties.     

Corn oil enhancing hepatic lipid peroxidation induced by CCl4 does not aggravate liver fibrosis in rats

Lipid peroxidation (LPO) is known to be associated with liver fibrosis in chronic liver injury. However, direct effects of the products of LPO on liver fibrogenesis have not been demonstrated. In this study, we examined the LPO products of carbon tetrachloride (CCl4)+corn oil to evaluate the effect of LPO products on liver fibrosis. CCl4 was given twice a week for 8 weeks. Corn oil was given daily to rats at a dose of 2 or 10ml/kg via gastrogavage throughout the whole experiment period. CCl4 induced both cyclooxygenase (COX)-2 independent and COX-2 dependent LPO. COX-2 independent LPO was enhanced by corn oil treatment while no effect was reflected on COX-2 dependent LPO. CCl4-induced liver fibrosis in rats was not aggravated by corn oil treatment. In addition, the amount of fatty liver induced by CCl4 was increased by corn oil treatment. Though the inflammation-related UCP-2 mRNA expression was induced by CCl4, it was not aggravated by the enhancement of corn oil. Conclusion: corn oil enriches polyunsaturated fatty acids through COX-2 independent pathways to increase LPO products that do not enhance liver fibrosis induced by CCl4.     

Pyridoxol L,2-pyrrolidon-5 carboxylate prevents active fibroplasia in CCl4-treated rats.

In the present study we evaluated the protective activity of pyridoxol L,2-pyrrolidon-5 carboxylate (metadoxine) against CCl4 intoxication in rats, especially in relation to liver fibrosis. After 6 consecutive weeks of CCl4 treatment, the animals developed liver fibrosis and inflammation as revealed by histological analysis which also included semiquantitative scoring of these features. In addition the serum levels of the immunoreactive prolyl hydroxylase (SIRPH), an enzyme involved in the hydroxylation of the procollagen molecule, were significantly higher (44.2 +/- 16.3 micrograms/ml; P less than 0.005) in this group of animals than in controls (26.1 +/- 8.06). On the contrary, animals treated with CCl4 + metadoxine (200 mg/kg i.p.) had less severe liver fibrosis and normal SIRPH levels (21.5 +/- 14.6). These data suggest that metadoxine may be an effective pharmacological tool for preventing the progression of liver disease in rats exposed to CCl4 to cirrhosis.     

Suppressive effect of tritoqualine on lipid peroxidation and enzyme leakage induced by carbon tetrachloride in rat hepatocytes

Since tritoqualine (TRQ) is effective in suppressing the increase of serum transaminases in acute hepatic injured rats induced by some hepatotoxins, protection of the hepatocyte membrane is suggested to be one of the pharmacological effects of TRQ. In the present study, we investigated the effects of TRQ on lipid peroxidation and enzyme leakage caused by carbon tetrachloride (CCl4) exposure in isolated hepatocytes and the liver in vivo, compared with vitamin E. The results were as follows: Hepatocytes isolated from TRQ-administered rats showed less enzyme leakage than those from control rats after CCl4 addition. TRQ displayed strong inhibition of lipid peroxidation in isolated hepatocytes. In comparison with vitamin E, TRQ showed almost the same inhibitory action on lipid peroxidation, but a stronger suppression of enzyme leakage. Vitamin E showed a weaker protection from increase of glutamic oxaloacetic transaminase than TRQ, in spite of its stronger inhibition of lipid peroxidation in vivo. From these results, it is suggested that the membrane protecting action of TRQ is partially derived from its suppression of lipid peroxidation, but "another action" may also play an important role in protecting the fragile membrane.     

乾坤宁保肝作用的实验研究

用四氯化碳（ＣＣｌ_４）诱导大鼠肝脏损伤，同时用乾坤宁灌喂以保护肝脏损伤，实验结束取动物血测定ＡＬＴ、ＡＳＴ、羟脯氨酸等生化指标，并对肝脏作组织病理学观察。实验各组的ＡＬＴ、ＡＳＴ均显著低于单用ＣＣｌ４组（Ｐ＜０．０１）；羟脯氨酸也低于单用ＣＣｌ_４组（０．０５＜Ｐ＜０．１）；组织病理观察发现，实验各组肝脏病理改变均轻于单用ＣＣｌ_４组，结果表明，乾坤宁对ＣＣｌ_４所致大鼠肝脏形态和功能损伤有明显的保护作用，对肝纤维化有一定预防作用。     

大黄酸抑制四氯化碳诱导的大鼠肝纤维化形成

目的:观察大黄酸对实验性肝纤维化的影响.方法:采用60％的四氯化碳(CCl_4)及5％的乙醇制备肝纤维化动物模型,分别用小剂量、大剂量大黄酸(25 mg/kg,100 mg/kg体重)干预,测定血清丙氨酸氨基转移酶(ALT)、透明质酸(HA)、Ⅲ型前胶(PC-Ⅲ)及肝组织丙二醛(MDA)含量,免疫组化方法观察转化生长因子 β1(TGF-β1)、α平滑肌肌动蛋白(α-SMA)的表达情况,并观察肝组织胶原面积及病理变化.结果:大黄酸组较模型组:(1)血清ALT、HA、PC-Ⅲ水平及肝组织中MDA含量显著降低(P<0.01);(2)肝组织中TGF-β1,α-SMA的表达显著减少(P<0.05或P<0.01);③肝组织胶原面积明显减少,纤维化程度明显改善(P<0.05或P<0.01).结论:大黄酸具有保肝作用和抑制肝纤维化作用,其作用机制可能与其抗炎、抗氧化作用及抑制HSC活化、抑制TGF-β1作用有关.     

豹皮樟总黄酮调控瘦素、TGF-β1对肝纤维化大鼠的预防作用研究

目的研究豹皮樟总黄酮(TFLC)调控瘦素(leptin)和转化生长因子-β1(TGF-β1)对肝纤维化大鼠的预防作用。方法采用CCl4诱导大鼠肝纤维化模型,TFLC灌胃给药第12周末,检测ALT、AST及HA、LN、PⅢNP、CⅣ含量;检测Ⅰ型胶原(CollagenⅠ)、瘦素、TGF-β1的含量;检测Hyp及组织病理变化;检测瘦素受体(OB-Rb)、TGFβ1Ⅰ型受体(TGFβR1)、Smad3 mRNA及蛋白表达。结果 TFLC(200、400 g.L-1)能明显降低肝纤维化大鼠肝纤维化指标及血清Ⅰ型胶原、瘦素、TGF-β1水平;降低Ob-Rb、TGFβR1、Smad3的mRNA及蛋白表达。结论 TFLC能有效预防CCl4诱导的大鼠肝纤维化,可能与下调肝内瘦素及其受体,抑制TGF-β1/Smad通路有关。     

Kupffer cells are responsible for liver cirrhosis induced by carbon tetrachloride

Inhibition of Kupffer cells could disrupt the sequence of events leading to organ injury by damping down the fibrogenic stimulus. To elucidate the role of Kupffer cells in liver fibrosis and cirrhosis, rats were treated with gadolinium chloride (GdCl(3)) and cirrhosis was induced by subchronic carbon tetrachoride (CCl(4)) administration. Carbon tetrachloride was administered three times per week for 8 weeks to male Wistar rats treated simultaneously with GdCl(3) (20 mg kg(-1), i.p. daily); appropriate controls were performed. Serum enzyme activities of alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (gamma-GTP) and alanine aminotransferase (ALT) and bilirubin concentration increased significantly by CCl(4), whereas GdCl(3) prevented completely the increase in gamma-GTP and partially prevented the increase in ALP, ALT and bilirubins (P < 0.05). Liver glycogen was depleted by CCl(4), an effect that GdCl(3) was not capable of preventing. Moreover, gadolinium by itself depleted it. Lipid peroxidation increased about 2.5-fold by administration with CCl(4), whereas GdCl(3) preserved lipid peroxidation within normal values. Hepatic collagen increased threefold after subchronic intoxication with CCl(4) (P < 0.05) whereas GdCl(3) prevented partially (P < 0.05) the increase in collagen content, as evidenced by the liver hydroxyproline content and by the histopathological analysis. The present results suggest that Kupffer cells are needed for the production of CCl(4)-induced cirrhosis, because their inactivation with GdCl(3) prevents the disease.     

Lipid peroxidation products do not activate hepatic stellate cells

Lipid peroxidation (LPO) is known to be associated with liver fibrosis in chronic liver injury. However, direct effects of the products of LPO on liver fibrogenesis are still not clear. In this study, we examined the LPO products, such as malondiladehyde (MDA), 8-iso-prostaglandin F(2alpha) (8-iso-PGF(2alpha)), and 15-keto-13,14-dihydro-PGF(2alpha) (15-keto-PGF(2alpha)), on the activation of hepatic stellate cells (HSCs) in vivo and in vitro. Carbon tetrachloride (CCl(4)) was given orally to rats twice a week for 8 weeks. Corn oil was given daily to rats for 8 weeks. CCl(4) induced both free-radical-medicated and cyclooxygenase-2-dependent LPO. Free radical-medicated LPO showed an increase with corn oil treatment, whereas no effect was reflected on COX-2-dependent LPO. CCl(4) induced liver fibrosis in rats, but no liver fibrosis was observed in rats treated with corn oil. In vitro studies demonstrated that MDA, 8-iso-PGF(2alpha) and 15-keto-PGF(2alpha), did not activate HSCs, which were preactivated or not preactivated by TGF-beta1. Our results clearly indicate that LPO products, such as MDA, 8-iso-PGF(2alpha) and 15-keto-PGF(2alpha), cannot directly activate HSCs.     

Effects of cianidanol (KB-53) on liver cirrhosis induced by CCl4 in rats: a pathological investigation

The therapeutic effects of cianidanol on the rat liver cirrhosis induced by CCl4 were investigated by means of pathological examination. Rats were administered with CCl4 subcutaneously twice a week for a consecutive 10 weeks. From a macroscopical viewpoint, pailing grayish discoloration, granular hyperplastic nodules and the disappearance of luster on the surface of the liver, and the formation of pseudolobule on the cut surface were observed in the control group. In the histopathological findings, degenerative fatty change and ballooning degeneration of parenchymal liver cells, a formation of pseudolobule caused by septal fibrosis proliferation, an acinar arrangement caused by pericellular fibrosis, and a cholangiollar proliferation were observed. All these abnormalities were diminished by the oral administration of 200 and 400 mg/kg of cianidanol for 7 days. The therapeutic effects of cianidanol were dose-dependent on the liver cirrhosis rats. Consequently, it is suggested that cianidanol has therapeutic effects on liver cirrhosis induced by CCl4 by relieving hepatocytes disorder, improving regeneration of hepatocytes and the absorption of proliferated fibrotic tissues.