Ursodeoxycholic acid treatment improves hepatocyte ultrastructure in rat liver fibrosis

Ultrastructural changes of donor livers in liver transplantation indicate hepatocytes injury

The use of electron microscopy (EM) can provide details about cells and tissue down to the nanometer level. We aim to observe ultrastructural changes in the donor liver by EM and analyze the relationship with prognosis. Data from 89 liver transplant recipients were collected and analyzed for recovery of graft function. The results revealed significantly higher organelle injury scores in the primary liver graft nonfunction (PNF) group. High-score group had higher peak alanine aminotransferases, peak aspartate aminotransferases, and peak international normalized ratio (p = .041, .006 and .036, respectively). Warm ischemia time, score of rough endoplasmic reticulum and nucleus was larger in low-score group (p = .007, .006, and .025, respectively). Patients in high-score group had a significantly short survival time (60.0% vs. 92.9%, p = .0039). No significant difference was found in the analysis of 3-year survival rate (60% vs. 84.5%, p = .07). EM is one of feasible and effective strategy for evaluating the quality of donor liver and the patient's prognosis. Ultrastructural changes under EM indicate hepatocytes injury and a high score indicates a worse outcome in early period but does not affect long-term survival.

Management strategies for liver fibrosis

Liver fibrosis resulting from chronic liver injury are major causes of morbidity and mortality worldwide. Among causes of hepatic fibrosis, viral infection is most common (hepatitis B and C). In addition, obesity rates worldwide have accelerated the risk of liver injury due to nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Also liver fibrosis is associated with the consumption of alcohol, or autoimmune hepatitis and chronic cholangiophaties. The response of hepatocytes to inflammation plays a decisive role in the physiopathology of hepatic fibrosis, which involves the recruitment of both pro- and anti-inflammatory cells such as monocytes and macrophages. As well as the production of other cytokines and chemokines, which increase the stimulus of hepatic stellate cells by activating proinflammatory cells. The aim of this review is to identify the therapeutic options available for the treatment of the liver fibrosis, enabling the prevention of progression when is detected in time.

Protective effect of ursodeoxycholic acid, resveratrol, and N-acetylcysteine on nonalcoholic fatty liver disease in rats

CONTEXT

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Resveratrol (RSV) and N-acetylcysteine (NAC) are safe representatives of natural and synthetic antioxidants, respectively.

OBJECTIVE

The objective of this study was to evaluate protective effects of RSV and NAC, compared with ursodeoxycholic acid (UDCA), on experimental NAFLD.

MATERIALS AND METHODS

NAFLD was induced by feeding rats a methionine choline-deficient diet (MCDD) for four cycles, each of 4 d of MCDD feeding and 3 d of fasting. Animals were divided into normal control, steatosis control, and five treatment groups, receiving UDCA (25 mg/kg/d), RSV (10 mg/kg/d), NAC (20 mg/kg/d), UDCA + RSV, and UDCA + NAC orally for 28 d. Liver integrity markers (liver index and serum transaminases), serum tumor necrosis factor-α (TNF-α), glucose, albumin, renal functions (urea, creatinine), lipid profile (total cholesterol; TC, triglycerides, high density lipoproteins, low density lipoproteins; LDL-C, very low density lipoproteins, leptin), and oxidative stress markers (hepatic malondialdehyde; MDA, glutathione; GSH, glutathione-S-transferase; GST) were measured using automatic analyzer, colorimetric kits, and ELISA kits, supported by a liver histopathological study.

RESULTS

RSV and NAC administration significantly improved liver index (RSV only), alanine transaminase (52, 52%), TNF-α (70, 70%), glucose (69, 80%), albumin (122, 114%), MDA (55, 63%), GSH (160, 152%), GST (84, 84%), TC (86, 86%), LDL-C (83, 81%), and leptin (59, 70%) levels compared with steatosis control values. A combination of RSV or NAC with UDCA seems to ameliorate their effects.

DISCUSSION AND CONCLUSION

RSV and NAC are effective on NAFLD through antioxidant, anti-inflammatory, and lipid-lowering potentials, where as RSV seems better than UDCA or NAC.

A Herbal Formula, CGXII, Exerts Antihepatofibrotic Effect in Dimethylnitrosamine-Induced SD Rat Model

We aimed to evaluate the antihepatofibrotic effects of CGXII, an aqueous extract which is composed of A. iwayomogi, A. xanthioides, and S. miltiorrhiza, against dimethylnitrosamine- (DMN-) induced hepatofibrosis. Male Sprague Dawley rats were intraperitoneally injected with 10 mg/kg of DMN for 4 weeks (three consecutive days weekly). Rats were orally given distilled water, CGXII (50 or 100 mg/kg), or dimethyl dimethoxy biphenyl dicarboxylate (50 mg/kg) daily. DMN injection caused substantial alteration of total body weight and liver and spleen mass, whereas they were notably normalized by CGXII. CGXII treatment also markedly attenuated the elevation of serum aspartate aminotransferase and alanine aminotransferase levels, hepatic lipid peroxidation, and protein carbonyl contents. Collagen accumulation in hepatic tissue evidenced by histopathological analysis and quantitative assessment of hepatic hydroxyproline was ameliorated by CGXII. Immunohistochemistry analysis revealed decreased α-smooth muscle actin supporting the antihepatofibrotic effect of CGXII. The profibrogenic cytokines transforming growth factor-β, platelet-derived growth factor-β, and connective tissue growth factor were increased by DMN injection. Administration of CGXII normalized the protein and gene expression levels of these cytokines. Our findings suggest that CGXII lowers the levels of profibrogenic cytokines and thereby exerts antifibrotic effects.

Protective Effects of Norursodeoxycholic Acid Versus Ursodeoxycholic Acid on Thioacetamide-induced Rat Liver Fibrosis

BACKGROUND/OBJECTIVES

Effects of norursodeoxycholic acid (norUDCA) and ursodeoxycholic acid (UDCA) on liver fibrosis progression and liver fibrosis reversal in thioacetamide (TAA)-treated rats were studied.

METHODS

Advanced liver fibrosis was induced by TAA treatment (200 mg/kg, i.p.) for 12 weeks. In the second experiment resolution of liver fibrosis was assessed after 8 weeks of TAA withdrawal. During 8 last weeks of each trial, fibrotic rats were daily administered with UDCA (80 mg/kg) and norUDCA (equimolar to 80 mg/kg of UDCA) by oral gavage. Liver fibrosis was assessed by Sirius red staining, liver hydroxyproline and serum fibrosis markers determination.

RESULTS

The TAA treatment resulted in advanced fibrosis and increase in liver hydroxyproline content and serum fibrosis markers. These signs of fibrosis were less pronounced in rats after TAA withdrawal. Treatment with of norUDCA significantly decreased the total and relative liver hydroxyproline contents in rats with fibrosis reversal, whereas UDCA did not change these parameters. Both compounds decreased serum TGFβ and type IV collagen contents, whereas other serum markers did not differ from the placebo group. In the fibrosis progression model the square of connective tissue was decreased by norUDCA. Serum type IV collagen and procollagen III-NT contents in these experiments were lowered by both UDCA and norUDCA, whereas rest of serum fibrosis markers were diminished only by norUDCA.

CONCLUSIONS

Both norUDCA and UDCA showed therapeutic and prophylactic antifibrotic effect in rats with TAA-induced liver fibrosis. For most of tested parameters norUDCA was more effective than UDCA, especially in the experiment with liver fibrosis regression.

Pathogenesis of liver cirrhosis

Liver cirrhosis is the final pathological result of various chronic liver diseases, and fibrosis is the precursor of cirrhosis. Many types of cells, cytokines and miRNAs are involved in the initiation and progression of liver fibrosis and cirrhosis. Activation of hepatic stellate cells (HSCs) is a pivotal event in fibrosis. Defenestration and capillarization of liver sinusoidal endothelial cells are major contributing factors to hepatic dysfunction in liver cirrhosis. Activated Kupffer cells destroy hepatocytes and stimulate the activation of HSCs. Repeated cycles of apoptosis and regeneration of hepatocytes contribute to pathogenesis of cirrhosis. At the molecular level, many cytokines are involved in mediation of signaling pathways that regulate activation of HSCs and fibrogenesis. Recently, miRNAs as a post-transcriptional regulator have been found to play a key role in fibrosis and cirrhosis. Robust animal models of liver fibrosis and cirrhosis, as well as the recently identified critical cellular and molecular factors involved in the development of liver fibrosis and cirrhosis will facilitate the development of more effective therapeutic approaches for these conditions.

The protective role of pomegranate juice against carbon tetrachloride–induced oxidative stress in rats

Most pomegranate ( Punica granatum Linn., Punicaceae) fruit parts are known to possess enormous antioxidant activity. The present study was carried out to determine the phenolic and flavonoid contents of Derik pomegranate juice and determine its effect against carbon tetrachloride (CCl4)-induced toxicity in rats. Animals were divided into four groups ( n = 6): group I: control, group II: CCl4 (1 ml/kg), group III: CCl4 + pomegranate juice and group IV: CCl4 + ursodeoxycholic acid (UDCA). Treatment duration was 4 weeks, and the dose of CCl4 was administered once a week to groups II, III and IV during the experimental period. CCl4-treated rats caused a significant increase in serum enzyme levels, such as aspartate aminotransferase, alanine aminotransferase and total bilirubin, and decrease in albumin, when compared with control. Administration of CCl4 along with pomegranate juice or UDCA significantly reduces these changes. Analysis of lipid peroxide (LPO) levels by thiobarbutiric acid reaction showed a significant increase in liver, kidney and brain tissues of CCl4-treated rats. However, both pomegranate juice and UDCA prevented the increase in LPO level. Histopathological reports also revealed that there is a regenerative activity in the liver and kidney cells. Derik pomegranate juice showed to be hepatoprotective against CCl4-induced hepatic injury. In conclusion, present study reveals a biological evidence that supports the use of pomegranate juice in the treatment of chemical-induced hepatotoxicity.

Magnesium chenoursodeoxycholic acid ameliorates carbon tetrachloride-induced liver fibrosis in rats

This study was designed to investigate the hepatoprotective effects of magnesium chenoursodeoxycholic acid (Mg-CUD), a magnesium trihydrate salt of ursodeoxycholic acid and chenodeoxycholic acid, in carbon tetrachloride (CCl(4))-induced liver fibrosis in rats. Rats were treated with CCl(4) dissolved in olive oil (0.5 mL/kg, twice a week) intraperitoneally for eight weeks. Mg-CUD was administered orally at 15.625, 31.25, 62.5 and 125 mg/kg once a day. Chronic CCl(4) administration induced increases in serum transforming growth factor-β1, hepatic hydroxyproline content and serum alanine aminotransferase activity. Mg-CUD attenuated these increases. The levels of α-smooth muscle actin protein and mRNA expression were increased by chronic CCl(4) exposure and Mg-CUD attenuated these increases. Mg-CUD suppressed increases in matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1 mRNA expression and elevation of oxidative stresses by attenuating lipid peroxidation and enhancing reduced glutathione/oxidized glutathione ratio. The overexpression of toll-like receptor 4 and increased nuclear translocation of nuclear factor-κB and phosphorylated c-Jun, a component of activator protein 1, were suppressed by Mg-CUD. Furthermore, CCl(4) increased the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10 and cyclooxygenase (COX)-2. Mg-CUD attenuated the levels of TNF-α, IL-6 and COX-2, while it augmented the level of IL-10. Our results suggest that Mg-CUD may prevent liver fibrosis by modulating collagen accumulation and inflammatory signaling pathways.

Morphine sulphate induced histopathological and histochemical changes in the rat liver

In this study, the histopathological and histochemical changes due to chronic usage of morphine sulphate in liver were assessed in rats with both light and electron microscopes. Twenty male albino rats (Rattus norvegicus) (130-150 g) were included and divided into four groups. Normal saline (5 ml) was given orally as placebo in the control group (N=5). Morphine groups (N=5) received morphine orally at a single dose of 5 ml/kg/day for 10, 20 and 30 days (groups II, III and IV), respectively. Liver specimens from all groups were evaluated for histopathological and histochemical changes. Light microscopy revealed severe centrilobular congestion, portal fibrosis with bile ductal proliferation and an increased inflammatory infiltration and focal parenchymal necrosis. Histochemical study revealed a progressive depletion of general carbohydrates and an increase in total protein contents. These changes were confirmed at ultrastructural level, including the presence of accumulated lipid in the hepatocytes; deposits of a collagen-like fibrous material were seen in the space of Disse and a reduction in the number of endothelial cell fenestrations. Our findings pointed out the risk of increased lipid fibrosis and hepatic damage due to long-term use of morphine. Although opioids are reported to be effective in pain management, their toxic effects should be kept in mind during chronic usage.

Recent advances in biliary atresia: prospects for novel therapies

BACKGROUND

Biliary atresia (BA) is a progressive fibro-obliterative disease of the extrahepatic biliary tree that presents with biliary obstruction before 2 months of age. Untreated BA is a uniformly fatal disease and even with our current therapies only 50% of children with BA will be transplant-free by 2 years of age. Despite descriptions of this disorder dating back to the 1800s our current therapies are palliative. They focus on prompt diagnosis, supportive nutritional care and interventions for sequelae.

OBJECTIVE

To present the literature supporting current treatment strategies and potential future therapies.

METHOD

Each of the aspects of care is described and the literature about nuances of care is provided.

CONCLUSION

Therapies will not improve outcomes until novel treatments are introduced, such as those suggested, which may intervene in the inflammatory or fibrotic steps of the disease process.

Ultrastructural changes in hepatocytes after taurine treatment in CCl4 induced liver injury

AIM: To search the organelle based changes in hepatocytes after taurine treatment in experimental liver fibrosis induced by CCl₄ administration.

METHODS: Thirty rats were divided into two groups. Group 1 (n = 15) was injected with CCl₄ plus taurine and Group 2 (n = 15) with CCl₄ plus saline for 12 wk. At the end of 12th wk, mitochondria, rough and smooth endoplasmic reticulum, and nuclei of hepatocytes were evaluated using a scoring system. The results were compared with histopathological findings, as well.

RESULTS: Taurine treatment reduced fibrosis scores significantly as compared to placebo. Organelle injury scores decreased significantly with taurine treatment. Ultrastructural and histopathological scores in both groups were in strong correlation (r = 0.931 for CCl₄ plus taurine and r = 0.899 for CCl₄ plus saline group).

CONCLUSION: Organelle based transmission electron microscopy findings can reflect successfully histological results as well as tissue healing in hepatocytes from hepatotoxin-induced liver fibrosis.