Bile Duct Ligation Group Research Articles

MODULATION OF TOLL-LIKE RECEPTOR GENES WITH SELECTIVE GUT DECONTAMINATION IN CIRRHOTIC ANIMALS PREVENTS THE DEVELOPMENT OF ACUTE-ON CHRONIC LIVER FAILURE (ACLF)

Introduction Acute deterioration in the liver function following precipitating illness in patients with cirrhosis often lead to multiple organ failure. Inflammation is thought to be a major contributing factor. We hypothesised that toll like receptor9s (TLRs) play a pivotal role in lipopolysaccharide (LPS) mediated cytokine surge in patients with cirrhosis culminating in acute-on-chronic liver failure (ACLF). Selective gut decontamination with Norfloxacin would dampen this inflammatory cascade. Methods Global hepatic gene expression was studied in a rodent model of cirrhosis induced by bile duct ligation (BDL) (Agilent microarray) and compared the results to sham animals. TLR related genes were among the differentially expressed genes in the liver. We validated gene expression in the Liver and Kidney in a second set of experiment in Sham, BDL, BDL+LPS, BDL+Norfloxacin, BDL+Norfloxacin+LPS groups using the quantitative real-time PCR. Cytokines (Becton Dickenson) and biochemistry were measured (COBAS Integra 400). Results Among the several genes with high expression in the BDL group as detected by the microarray, both TLR 4 and 2 had significantly higher expression in liver and Kidney compared with the sham group. We also found a marked upregulation of the C-C motif ligand 2 (CCl2) and C-X-C motif ligand 2(CxCl2) Furthermore, LPS administration in BDL animals accentuated not only the TLRs (4 and 2) expression in both kidney and liver but also the Cxcl2 and CCl2 in both these organs associated with deterioration organ function as suggested with a rise in the liver enzyme, creatinine and a rise in plasma and tissue cytokines. Norfloxacin pre-treatment in BDL group (BDL+Norfloxacin) attenuated the TLR4 and TLR2 expression in both liver and kidney. Selective decontamination with Norfloxacin in BDL +LPS animals limited the upregulation of TLR4 and TLR2 in the Liver and Kidney. It also prevented the upregulation of the CxcL2 and CCl2 in both these organs. This was associated with significant improvement in liver enzymes, creatinine and cytokines. Conclusion This study shows that the liver and kidneys in cirrhotic animals are primed by upregulation of TLR9s and its downstream inflammatory mediators in the Liver and Kidney which make them exquisitely sensitive to the effects of superimposed infection/inflammation leading to organ failure. Selective decontamination with Norfloxacin prevents the progression of ACLF by reducing gene expression of TLR 2 and 4 and its associated inflammatory adaptors. Competing interests None declared.

577 ALBUMIN IS CENTRAL IN MEDIATING THE CARDIO-RENAL DYSFUNCTION OF CIRRHOSIS: A STUDY IN ANALBUMINAEMIC RATS

Introduction Albumin is a multifunctional protein which is reduced in concentration and function in liver disease. Albumin infusion prevents and improves renal dysfunction in patients with advanced liver failure but the mechanisms of its beneficial properties are unclear. We hypothesised that albumin is central in the maintenance of cardio-renal function in cirrhosis and albumin impairment worsens outcome. In order to answer this question we investigated analbuminaemic rats, characterised by lack of albumin but with normal protein concentration, following induction of cirrhosis with bile duct ligation (BDL). Methods Male Sprague-Dawley (SD) and Nagase analbuminaemic (NAR) rats were studied 6 weeks after BDL or sham surgery (n=6 sham-SD, 8 sham-NAR, 7 SD-BDL, 7 NAR-BDL). Rats underwent systemic mean arterial pressure (MAP) and portal pressure (PP) assessment under terminal anaesthesia. Plasma and urine were collected for measurements of renal function and protein profile. Plasma renin activity (PRA) was measured as a marker of cardio-renal dysfunction. Urinary neopterin, a marker of macrophage activation was assessed. Results NARs showed plasma total protein concentration similar to SD despite lack of albumin before (72±15 vs 82±8) and after BDL (67±7 vs 75±22). After BDL both groups of animals showed histological evidence of severe liver damage, though the NARs showed a significantly worse systemic haemodynamics with lower MAP (p=0.01), evidence of renal dysfunction indicated by higher plasma creatinine and higher PRA (p Conclusion A lack of albumin was associated with a raised PRA and a marked deterioration in systemic haemodynamics and renal function after liver injury (BDL), despite normal total plasma protein concentration. This worsened outcome in the absence of albumin strongly supports the central role of albumin in maintenance of cardio-renal function in liver failure and may indicate that albumin plays a crucial role in moderating inflammation. Competing interests None declared.

Protective effects of thymoquinone against cholestatic oxidative stress and hepatic damage after biliary obstruction in rats

The aim of this study was to examine the preventive and therapeutic effects of thymoquinone (TQ) against cholestatic oxidative stress and liver damage in common bile duct ligated rats. A total of 24 male Sprague-Dawley rats were divided into three groups: control, bile duct ligation (BDL) and BDL + received TQ; each group contain 8 animals. The rats in TQ treated groups were given TQ (50 mg/kg body weight) once a day orally for 2 weeks starting 3 days prior to BDL operation. To date, no more biochemical and histopathological changes on common bile duct ligated rats by TQ treatment have been reported. The application of BDL clearly increased the tissue hydroxyproline (HP) content, malondialdehyde (MDA) levels and decreased the antioxidant enzyme [superoxide dismutase (SOD), glutathione peroxidase (GPx)] activities. TQ treatment significantly decreased the elevated tissue HP content, and MDA levels and raised the reduced of SOD, and GPx enzymes in the tissues. The changes demonstrating the bile duct proliferation and fibrosis in expanded portal tracts include the extension of proliferated bile ducts into lobules, mononuclear cells, and neutrophil infiltration into the widened portal areas were observed in BDL group. Treatment of BDL with TQ attenuated alterations in liver histology. The immunopositivity of alpha smooth muscle actin and proliferating cell nuclear antigen in BDL were observed to be reduced with the TQ treatment. The present study demonstrates that oral administration of TQ in bile duct ligated rats maintained antioxidant defenses and reduces liver oxidative damage and ductular proliferation. This effect of TQ may be useful in the preservation of liver function in cholestasis.

Cytokine response to portal endotoxaemia and neutrophil stimulation in obstructive jaundice

An exaggerated proinflammatory response to endotoxaemia can occur in obstructive jaundice. The aims of this study were to determine the hepatic proinflammatory and anti-inflammatory cytokine response to endotoxaemia in experimental biliary obstruction and to determine the source of interleukin-6 (IL-6) using immunohistochemistry. Male Wistar rats were randomized into three groups: bile duct ligation (BDL), sham operation, and control groups. They were weighed before surgery and after 1 week. On day 8, hepatic perfusion was performed with endotoxin (Escherichia coli 0111:B4). Serial samples of blood, effluent, and influent perfusate were analyzed for proinflammatory and anti-inflammatory cytokines. Ultrastructural assessment of sections of the liver was performed. BDL animals lost weight in the first week compared with the sham and the control animals that gained weight. Liver function tests were elevated in the BDL group. Effluent biochemistry did not reveal liver injury as a result of perfusion. Ultrastructurally, there was no evidence of liver injury, with only active Kupffer cells, preservation of liver architecture, and minimal liver injury being detected. Serum tumor necrosis factor-α was not detected in any group before perfusion; however, serum IL-6 was higher in the BDL group. Portal endotoxaemia resulted in an increase in tumor necrosis factor-α, IL-6, and IL-10 in the BDL group. Fluorescence immunohistochemistry demonstrated IL-6 in the sinusoidal spaces and the cytoplasm of Kupffer cells. There is an exaggerated proinflammatory and anti-inflammatory cytokine response to portal endotoxaemia in animals with jaundice compared with the sham group.

The protective role of natural phytoalexin resveratrol on inflammation, fibrosis and regeneration in cholestatic liver injury

Liver injuries can trigger a cascade of inflammatory responses and as a result, initiate the process of hepatic regeneration and fibrogenesis. Resveratrol (RSV) has multiple health-promoting benefits. This study evaluated the potential protective effects and mechanism of RSV as related to cholestatic liver injury. RSV was given (4 mg/kg/day, i.p.) for either 3 days or 7 days after bile duct ligation (BDL) injury. RSV significantly reduced serum ALT, AST but not T-bil on Day 3. At this early stage of injury, RSV significantly reduced TNF-α and IL-6 mRNA and decreased the number of Kupffer cells (CD68(+) ) recruited in the injured liver. RSV decreased hepatic fibrosis and reduced collagen Iα1 and TIMP-1 mRNA on Day 7. At the later stages of injury, RSV increased the number of Ki67(+) hepatocytes indicating that RSV promoted hepatocyte proliferation. Additionally, it resulted in decreased expression of 4-hydroxynonenal and increased expression of the hepatocyte growth factor protein and mRNA in the RSV-treated BDL group. Meanwhile, RSV reduced the mortality rate of BDL mice. In conclusion, RSV attenuated inflammation and reduced Kupffer cells activation. RSV decreased fibrosis and promoted hepatocyte regeneration, which increased the survival of BDL mice. RSV was beneficial for the treatment of cholestatic liver injury.

Assessment of proteolytic degradation of the basement membrane: a fragment of type IV collagen as a biochemical marker for liver fibrosis

BackgroundCollagen deposition and an altered matrix metalloproteinase (MMP) expression profile are hallmarks of fibrosis. Type IV collagen is the most abundant structural basement membrane component of tissue, which increases 14-fold during fibrogenesis in the liver. Proteolytic degradation of collagens by proteases produces small fragments, so-called neoepitopes, which are released systemically. Technologies investigating MMP-generated fragments of collagens may provide more useful information than traditional serological assays that crudely measure total protein. In the present study, we developed an ELISA for the quantification of a neoepitope generated by MMP degradation of type IV collagen and evaluated the association of this neoepitope with liver fibrosis in two animal models.MethodsType IV collagen was degraded in vitro by a variety of proteases. Mass spectrometric analysis revealed more than 200 different degradation fragments. A specific peptide sequence, 1438'GTPSVDHGFL'1447 (CO4-MMP), in the α1 chain of type IV collagen generated by MMP-9 was selected for ELISA development. ELISA was used to determine serum levels of the CO4-MMP neoepitope in two rat models of liver fibrosis: inhalation of carbon tetrachloride (CCl4) and bile duct ligation (BDL). The levels were correlated to histological findings using Sirius red staining.ResultsA technically robust assay was produced that is specific to the type IV degradation fragment, GTPSVDHGFL. CO4-MMP serum levels increased significantly in all BDL groups compared to baseline, with a maximum increase of 248% seen two weeks after BDL. There were no changes in CO4-MMP levels in sham-operated rats. In the CCl4 model, levels of CO4-MMP were significantly elevated at weeks 12, 16 and 20 compared to baseline levels, with a maximum increase of 88% after 20 weeks. CO4-MMP levels correlated to Sirius red staining results.ConclusionThis ELISA is the first assay developed for assessment of proteolytic degraded type IV collagen, which, by enabling quantification of basement membrane degradation, could be relevant in investigating various fibrogenic pathologies. The CO4-MMP degradation fragment was highly associated with liver fibrosis in the two animal models studied.

The efficiency of CAPE on retardation of hepatic fibrosis in biliary obstructed rats

The aim of this study was to evaluate the possible protective effects of caffeic acid phenethyl ester (CAPE) against cholestatic oxidative stress and liver damage in the common bile duct ligated rats. A total of 18 male Sprague-Dawley rats were divided into three groups: control, bile duct ligation (BDL) and BDL + received CAPE; each group contain 6 animals. The rats in CAPE treated groups were given CAPE (10 μmol/kg) once a day intraperitoneally (i.p) for 2 weeks starting just after BDL operation. The changes demonstrating the bile duct proliferation and fibrosis in expanded portal tracts include the extension of proliferated bile ducts into lobules, inflammatory cell infiltration into the widened portal areas were observed in BDL group. Treatment of BDL with CAPE attenuated alterations in liver histology. The proliferating cell nuclear antigen and the activity of TUNEL in the BDL were observed to be reduced with the QE treatment. The application of BDL clearly increased the tissue hydroxyproline (HP) content, malondialdehyde (MDA) levels and decreased the antioxidant enzyme (superoxide dismutase (SOD), glutathione peroxidase (GPx)) activities. CAPE treatment significantly decreased the elevated tissue HP content, and MDA levels and raised the reduced of SOD, and GPx enzymes in the tissues. The data indicate that CAPE attenuates BDL-induced cholestatic liver injury, bile duct proliferation, and fibrosis. The hepatoprotective effect of CAPE is associated with antioxidative potential.

Pravastatin for thioacetamide-induced hepatic failure and encephalopathy

Nitric oxide (NO) inhibition aggravates hepatic damage and encephalopathy and increases mortality in rats with thioacetamide (TAA)-induced acute liver failure. Statins enhance NO production but whether they influence the above parameters are unknown. Male Sprague-Dawley rats were used. In the first series, TAA (350 mg/kg per day, i.p. for 3 days) was administered to induce acute liver failure. Control rats received saline. Rats received distilled water or pravastatin (20 mg/kg per day, p.o.) from 2 days before to 3 days after TAA or saline injection. In the second series, liver cirrhosis was induced by common bile duct ligation (BDL). Sham-operated rats served as controls. Rats received distilled water or pravastatin for 5 or 14 days until the 42nd day after operation. On the last day of treatment, survival, motor activities, serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, ammonia and brain histology were evaluated. Thioacetamide and BDL rats showed higher ALT, AST, bilirubin and ammonia levels and lower motor activity counts compared with their corresponding control groups. In TAA rats, pravastatin elicited higher total and ambulatory motor activity counts and lower AST and total bilirubin levels. Survival was improved, whereas brain H&E staining was not significantly different in TAA rats with or without pravastatin treatment. In BDL groups, rats with or without pravastatin treatment were not different in motor activity counts and liver biochemistry. Pravastatin ameliorates hepatic encephalopathy and liver biochemistry and improves survival in rats with acute liver failure, but not in those with cirrhosis.

Beneficial effect of docosahexaenoic acid on cholestatic liver injury in rats

Bile duct obstruction and subsequent cholestasis are associated with hepatocellular injury, cholangiocyte proliferation, stellate cell activation, Kupffer cell activation, oxidative stress, inflammation and fibrosis. Docosahexaenoic acid (DHA) is an essential polyunsaturated fatty acid that has been shown to possess health beneficial effects, including hepatoprotection. However, the molecular mechanism of DHA-mediated hepatoprotection is not fully understood. In the present study, we report the protective effect of DHA on cholestatic liver injury. Cholestasis was produced by bile duct ligation (BDL) in male Sprague–Dawley rats for 3 weeks. Daily administration of DHA was started 2 weeks before injury and lasted for 5 weeks. In comparison with the control group, the BDL group showed hepatic damage as evidenced by histological changes and elevation in serum biochemicals, ductular reaction, fibrosis, inflammation and oxidative stress. These pathophysiological changes were attenuated by chronic DHA supplementation. DHA alleviated BDL-induced transforming growth factor beta-1 (TGF-β1), intereukin-1beta, connective tissue growth factor and collagen expression. The anti-fibrotic effect of DHA was accompanied by reductions in α-smooth muscle actin-positive matrix-producing cells and Smad 2/3 activity critical to the fibrogenic potential of TGF-β1. DHA also attenuated BDL-induced leukocyte accumulation and nuclear factor-κB (NF-κB) activation. Further studies demonstrated an inhibitory effect of DHA on redox-sensitive intracellular signaling molecule extracellular signal-regulated kinase (ERK). Taken together, the hepatoprotective, anti-inflammatory and anti-fibrotic effects of DHA seem to be multifactorial. The beneficial effects of chronic DHA supplementation are associated with anti-oxidative and anti-inflammatory potential as well as down-regulation of NF-κB and transforming growth factor beta/Smad signaling probably via interference with ERK activation.

Dexamethasone decreases cholestatic liver injury via inhibition of intrinsic pathway with simultaneous enhancement of mitochondrial biogenesis

Background Mitochondria are known to be involved in cholestatic liver injury. We tested the hypothesis that glucocorticoids can modulate mitochondrial function to alleviate cholestatic liver injury. Methods A rat model of cholestasis was established by bile duct ligation (BDL), with a sham group receiving laparotomy without BDL, and a group receiving dexamethasone (DEX) treatment after BDL. Results The liver function including total bilirubin levels, alanine transaminase and aspartate transaminase activities was significantly improved in the DEX treatment group in comparison to the BDL group. There was a significant upregulation of liver peroxisome proliferator-activated receptor γ coactivator-1α and mitochondrial transcriptional factor A protein between 6 and 72 h was found in the DEX group. DEX treatment significantly down-regulated Bax, caspase 9 and caspase 3 expression induced by BDL at 24–72 h, but had little effect on the expression of caspase 8, Bcl 2, Fas and Fas-FasL complex. Consequently, the number of apoptotic liver cells in the DEX group was significantly less than in the BDL group at 72 h. Conclusion Our results indicate that glucocorticoids decreases cholestatic liver injury within hours after BDL. Early glucocorticoids treatment can enhance the mitochondrial biogenesis and modulate the intrinsic but not extrinsic pathway of apoptosis following BDL.

Therapeutic effects of vitamin A on experimental cholestatic rats with hepatic fibrosis

The aim of this study is to investigate the role of hepatic stellate cells (HSCs) and the effect of vitamin A administration on liver damage induced by bile duct ligation (BDL) and administration of CCl(4). Two types of animal model were used; one was BDL as a model of biliary atresia, the other was CCl(4)-induced hepatic fibrosis. Pathological changes of the liver with or without administration of vitamin A were compared by light and electron microscopy with focusing on HSCs in each experimental group. Immunohistochemical examination was performed with anti-keratinocyte growth factor (KGF), anti-alpha-smooth muscle actin (α-SMA), and anti-glial fibrillary acidic protein (GFAP) antibodies, as markers of fibrosis. On light microscopic findings, periportal inflammation with bile ductular proliferation was obvious in BDL group and pericentral necrosis with fatty degeneration was observed in CCl(4) group, both of which were ameliorated by subcutaneous injection of vitamin A. Electron microscopy showed lipid droplets were almost depleted in the HSCs treated with BDL or CCl(4), which improved with vitamin A administration. Immunohistochemistry demonstrated that enhanced expression of all three fibrotic markers in the BDL group was diminished by vitamin A administration. Although most of our data are qualitative observation, vitamin A may ameliorate hepatic fibrosis in the BDL model by restoring vitamin A in the HSCs.

Protective effect of quercetin on liver damage induced by biliary obstruction in rats

The aim of this study was to evaluate the possible protective effects of quercetin (QE) against cholestatic oxidative stress and liver damage in the common bile duct ligated rats. A total of 24 male Wistar albino rats were divided into three groups: control, bile duct ligation (BDL) and BDL+received QE; each group contain 8 animals. The rats in QE treated groups were given QE (15mg/kg) once a day intraperitoneally for 4weeks starting 3days prior to BDL operation. The changes demonstrating the bile duct proliferation and fibrosis in expanded portal tracts include the extension of proliferated bile ducts into lobules, mononuclear cells, and neutrophil infiltration into the widened portal areas were observed in BDL group. Treatment of BDL with QE attenuated alterations in liver histology. The alpha smooth muscle actin (α-SMA), transforming growth factor beta (TGF-β1) positive cells and the activity of TUNEL in the BDL were observed to be reduced with the QE treatment. The data indicate that QE attenuates BDL-induced cholestatic liver injury, bile duct proliferation, and fibrosis. The hepatoprotective effect of QE is associated with antioxidative potential.

P57 Administration of branched chain amino acids to hyperammonemic cirrhotic animals is associated with worsening of hyperammonemia and increase in brain oedema

IntroductionDespite branched chain amino acids (BCAA) being used for over 30 years, its efficacy in treating hyperammonemia remains controversial. Recent studies suggest that the use of BCAA in cirrhosis is...

Effects of a long-acting somatostatin analogue, lanreotide, on bile duct ligation-induced liver fibrosis in rats

Somatostatin receptors have been shown on hepatic stellate cells, and somatostatin infusion has been shown to inhibit hepatic stellate cells activation. We aimed to test the effects of a long-acting somatostatin analogue, lanreotide, on bile duct ligation-induced liver fibrosis in rats. Thirty-seven Wistar rats were divided into 5 groups as follows: Group 1, bile duct ligation+lanreotide; Group 2, bile duct ligation; Group 3, sham+lanreotide; Group 4, sham; and Group 5, control group. Lanreotide-autogel (20 mg/kg/month) or saline in intraperitoneal doses was administered. Serum biochemical parameters, liver collagen level, and oxidative stress and histological parameters were determined after 28 days. The tissue collagen level, biochemical parameters (AST, ALT, bilirubins, alkaline phosphatase, γ-glutamyl transpeptidase) and oxidative stress parameters (malondialdehyde, luminal, lucigenin) in the bile duct ligation groups were higher than in the sham-operated and control groups (p<0.001 for all). Lanreotide improved malondialdehyde and glutathione levels in the bile duct ligation+lanreotide group. In histopathological examination, bile duct ligation groups showed stage-3 liver fibrosis, while all the controls were normal. Lanreotide did not improve the liver fibrosis histologically or biochemically. A monthly active somatostatin analogue, lanreotide, improved malondialdehyde and glutathione; however, it was not able to improve bile duct ligation-induced liver fibrosis in rats. Although lanreotide is a long-acting medication, it did not show anti-fibrotic effects in the model.

P58 Evidence of dendritic cell dysfunction in cirrhosis and its restoration by Toll-like receptor 4 antagonism

IntroductionInfection complicates the course of cirrhosis and is the main cause of admission of patients to hospital. Recent studies have shown evidence of immune paralysis during severe decompensation. Our studies...

OP08 Evidence for early astrocyte activation, cellular stress and compensatory microglial related transforming growth factor-α responses in bile-duct ligated rats

IntroductionInflammation and ammonia are important mediators in the pathogenesis of hepatic encephalopathy and though the mechanisms are unclear astrocytes are thought to have a central role. Recently Microglia, which also...

P60 Acute lowering of portal pressure in cirrhotic rats by Anti-TNF therapy is associated with reduced NFkB-driven inflammation and improved eNOS function through the asymmetric dimethylarginine-dimethylarginine-diaminohydrolase axis

IntroductionAnti-TNF (Infliximab) monotherapy has been shown to reduce hepatic inflammation and lower portal pressure in alcoholic hepatitis patients. Although the side effect profile of Infliximab limits its clinical use in...

The effects of the selective mineralocorticoid receptor antagonist eplerenone on hepatic fibrosis induced by bile duct ligation in rat

The aim of this study was to examine the effects of eplerenone on hepatic fibrosis induced by bile duct ligation (BDL) in rat. Low- (1.0 mg/kg body weight, BW) and high- (4.0 mg/kg BW) dose eplerenone was administered orally for 21 days immediately following BDL. Fibrosis was assessed by measuring the fibrotic area after Sirius red staining. Immunostaining for alpha-smooth muscle actin (SMA), 4-hydroxy-2-nonenal (4-HNE) and 8-hydroxy-2-deoxyguanosine (8-OHdG) was also carried out. Gene expression levels of procollagen-I, transforming growth factor-beta1 (TGF-beta1), connective tissue growth factor (CTGF), tissue inhibitor of metalloproteinases-1 (TIMP-1) and matrix metalloproteinase-13 (MMP-13) in the liver were examined by real-time reverse transcriptase polymerase chain reaction. Plasma angiotensin II (ATII) concentration was measured via radioimmunoassay. The area of hepatic fibrosis and alpha-SMA positivity in the high-dose group was significantly decreased compared with that in the BDL group, but not in the low-dose group. 8-OHdG-positive cells in the low- and high-dose groups were significantly decreased compared with those in the BDL group. Immunostaining of 4-HNE in the high-dose group was significantly lower compared with that in the BDL group. Furthermore, TIMP-1 mRNA levels in the low- and high-dose groups were lower than that in the BDL group. The expression of TGF-beta1, CTGF, procollagen-1 and MMP-13 showed no differences. Plasma ATII concentration in the high-dose group was significantly decreased. Eplerenone attenuated the development of BDL-induced hepatic fibrosis by reducing oxidative stress, suppressing activated hepatic stellate cells and decreasing plasma ATII levels. Eplerenone may prove useful as an alternative treatment for antifibrosis therapy.

Procollagen type I N-terminal propeptide (PINP) is a marker for fibrogenesis in bile duct ligation-induced fibrosis in rats

BackgroundFibrosis can be described as the excess deposition of extracellular matrix (ECM) components, such as collagens and proteoglycans. Fibrosis of the liver, which eventually leads to cirrhosis, is a major global health problem. Being able to measure fibrosis progression may enable timely preventative intervention. The aim of the current study was to investigate the utility of serum procollagen type I N-terminal propeptide (PINP) as a marker of hepatic fibrosis, as distinct from bone formation, during three different periods of fibrosis development following hepatic injury induced by bile duct ligation (BDL) in rats.MethodsBDL was performed on 30 female Sprague-Dawley rats aged 6 months, and sham operations on 30 controls. Animals were killed after 14, 28, or 35 days. The extent of liver fibrosis was evaluated by quantitative histology after Sirus Red staining. Levels of serum PINP and osteocalcin (a marker solely for osteoblastic bone formation) were determined using ELISA at baseline and post termination.ResultsCollagen formation increased by 30% compared to 3% in sham-operated animals (P < 0.0001). PINP levels increased significantly in all BDL groups compared with baseline (14 days: baseline 13.9 ng/ml, termination 17.7 ng/ml, P = 0.047; 28 days: baseline 17.9 ng/ml, termination 26.2 ng/ml, P = 0.005; 35 days: baseline 18.0 ng/ml, termination 27.4 ng/ml P = 0.015, an increase of 52%). PINP levels did not change from baseline in the sham-operated rats, indicating that the increased PINP levels were due to hepatic injury. The bone-specific marker, osteocalcin, did not increase in either BDL or sham-operated rats. PINP measured in serum correlated to the extent of liver fibrosis as evaluated by quantitative histology (R2 = 0.42, P < 0.001).ConclusionPINP was associated with the development of liver fibrosis, but not bone formation, in mature rats subjected to BDL. Thus, PINP may be useful in studying the pathogenesis of liver fibrosis. However, caution should be applied when interpreting PINP levels in other disease states.

Effect of rosuvastatin on cholestasis‐induced hepatic injury in rat livers

Recent studies reported that 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors have pleotropic effects independent of their lipid-lowering properties. The present study was undertaken to determine whether treatment with rosuvastatin (RO) would be beneficial in a rat model of bile duct ligation (BDL). Animals were divided into three groups: a sham group (group I), a BDL group treated with vehicle (group II), and a BDL group treated with RO (10 mg/kg) (group III). Serum levels of total bilirubin, gamma-glutamyl transpeptidase, alanine aminotransferase, and aspartate aminotransferase decreased significantly in group III when compared to group II. Lipid peroxides and NO levels of group III were found to be significantly lower than those of group II. Antioxidant enzymes (superoxide dismutase, glutathione-S-transferase, and catalase) activity in liver tissues markedly decreased in group II, whereas treatment with RO preserved antioxidant enzyme activity. DT-diaphorase activity in group II was significantly higher than that in group III. The histopathological results showed multiple numbers of newly formed bile ductules with inflammatory cells infiltration in group II. These pathological changes were improved in group III. Our data indicate that RO ameliorates hepatic injury, inflammation, lipid peroxidation and increases antioxidant enzymes activity in rats subjected to BDL. RO may have a beneficial effect on treatment of cholestatic liver diseases.