Reversibility of secondary biliary fibrosis by biliodigestive anastomosis in the rat

Elastography for Evaluation of Regression in Liver Fibrosis After Surgical Biliary Drainage for Benign Biliary Strictures: A Practical Possibility?

BACKGROUND

Hepatic fibrosis and secondary biliary cirrhosis are consequences of long-standing benign biliary strictures. Evidence on the reversibility of fibrosis after the repair is incongruous.

METHODOLOGY

A prospective observational study on patients who underwent Roux-en-Y hepaticojejunostomy for benign biliary stricture. A liver biopsy was performed during repair and correlated with preoperative elastography. The improvement in liver functions and regression of fibrosis was compared with preoperative liver function tests and elastography.

RESULTS

A Total of 47 patients [mean age-38.9 y (Range: 21 to 66)] with iatrogenic benign biliary stricture were included. A strong female preponderance was noted. High strictures (type III and IV) comprised 72.7% of the study group. The median interval (injury to repair) was 7 months (2 to 72 mo). The median duration of jaundice was 3 months (1 to 20 mo). Both factors had a significant correlation with the stage of fibrosis ( P =0.001 and P =0.03, respectively). Liver biopsy revealed stage I, II, III, and IV fibrosis in 26 (55.3%), 11 (23.4%), 2 (4.3%), and 2(4.3%), respectively. The remaining 6 (12.8%) had no fibrosis. The severity of fibrosis had a good correlation with preoperative liver stiffness measurement-value on FibroScan. Significant improvement in liver function tests (bilirubin-3.55±3.48 vs. 0.59±0.52; Albumin-3.85±0.61 vs. 4.14±0.37; ALP-507.66±300.65 vs. 167±132.07; P value 0.00) and regression of fibrosis (liver stiffness measurement; 10.42±5.91 vs. 5.85±3.01, P value 0.00) was observed after repair of the strictures.

CONCLUSION

Improved biliary function and regression of liver fibrosis can be achieved with timely repair of benign biliary stricture and it is feasible to be evaluated using elastography.

Liver fibrosis: the good, the bad, and the patchy-an update

The purpose of this article is to review fibrosis staging systems, reversibility of fibrosis, histologic pattern of fibrosis regression, and recently proposed fibrosis staging systems that address the more nuanced fibrosis information needed clinically for management purposes. In most chronic liver diseases, the extent of liver fibrosis often drives patient outcomes. The evolving knowledge of the reversibility of fibrosis and the observed patterns of fibrosis seen in the setting of remodeling/regression can create staging difficulties, and problems in applying the existing "conventional" staging systems. The heterogeneity of liver fibrosis in congestive liver disease is an emerging problem in biopsies from patients with congestive heart failure. The fibrosis staging in these biopsies is of significant import as it is used to determine suitability of some congestive heart disease patients for heart transplantation alone, dual heart and liver transplantation, or be denied transplantation. Pathologist should be aware of these newly recognized concepts, the recently proposed staging systems that attempt to incorporate these new fibrosis patterns and be able to apply the knowledge in daily practice.

Species specific morphological alterations in liver tissue after biliary occlusion in rat and mouse: Similar but different

Background

The selection of the appropriate species is one of the key issues in experimental medicine. Bile duct ligation is the mostly used experimental model in rodents to explore special aspects of occlusive cholestasis. We aimed to clarify if rats or mice are suitable for the same or different aspects in cholestasis research.

Methods

We induced biliary occlusion by ligation and transection of the common bile duct (tBDT) in rats and mice (each n = 25). Recovery from surgical stress was assessed by daily scoring (stress score, body weight). At five different time points (days 1, 3, 7, 14, 28 after tBDT) we investigated hepatic morphometric and architectural alterations (Haematoxylin-Eosin staining, Elastica van Gieson staining) and the proliferative activities of parenchyma cells (Bromodeoxyuridine staining); as well as established systemic markers for liver synthesis, hepatocellular damage and renal dysfunction.

Results

We found substantial differences regarding survival (rats: 100%, 25/25 vs. mice 92%, 22/25, p = 0.07) and body weight gain (p<0.05 at postoperative days 14 and 28 (POD)). Rats showed a faster and progressive hepatobiliary remodelling than mice (p<0.05 at POD 7+14+28), resulting in: i) stronger relative loss of hepatocellular mass (rats by 31% vs. mice by 15% until POD 28; p<0.05 at POD 7+14+28); ii) rapidly progressing liver fibrosis (p<0.05 at POD 14); iii) a faster and stronger proliferative response of parenchyma cells (hepatocytes: p<0.05 at POD 1+14+18; cholangiocytes: p<0.05 at POD 1+3+7+28); and iv) only tiny bile infarcts compared to mice (p<0.05 at POD 1+3+7+14). Both species showed comparable elevated markers of hepatocellular damage and serum bilirubin.

Conclusion

The key difference between rats and mice are the severity and dynamics of histological alterations, possibly accounting for their different susceptibilities for (septic) complications with low survival (mice).

MicroRNA-92b-3p promotes the progression of liver fibrosis by targeting CREB3L2 through the JAK/STAT signaling pathway

Liver fibrosis is a common feature of almost all chronic liver diseases, which eventually leads to cirrhosis and even hepatocellular carcinoma (HCC). The current study showed that miR-92b plays an important role in the progression of HCC but its role in liver fibrosis is still unclear. Here we aimed to explore the role and underlying molecular mechanism of miR-92b-3p in the activated hepatic stellate cells (HSCs) and the pathological process of hepatic fibrosis. We found that miR-92b-3p was highly expressed both in fibrotic liver tissues from patients and model mice and in activated LX-2 cells stimulated with TGF-β1. However, the expression of miR-92b-3p was downregulated in inactivated LX-2 cells treated with adipogenic differentiation mixture (MDI). In addition, we found that miR-92b-3p mimic could promote the activation, proliferation, and migration of LX-2 and HSC-T6 cells, while miR-92b-3p inhibitor could reverse this process. From the TargetScan databases, we found that CREB3L2 is a potential target of miR-92b-3p and the luciferase assay revealed the suppressed CREB3L2 expression by miR-92b-3p. Mechanistically, we found that miR-92b-3p promotes the activation of HSCs and thereby the progression of liver fibrosis by activating JAK/STAT pathway via targeting CREB3L2, providing a new target for the diagnosis and treatment of liver fibrosis.

Reversible biliary occlusion in a small animal model: first description of a new technique

Background

Experimental models with reversible biliary occlusion resulted in a high mortality of the animals, up to 20–60% according to the literature. Our aim was to assess a safe and valid technique for reversible biliary occlusion with a low mortality.

Methods

We randomized 30 rats into two groups: with bile duct occlusion (BDO, n=18) and with sham manipulation of the extrahepatic bile duct (control, n=12). We used a removable vascular clip for temporary occlusion of the extrahepatic bile duct. The clip was removed on postoperative day (POD) 2. On POD 2, 3, and 5, we measured the hepatocellular injury and metabolic function markers in serum. Activation of mononuclear cells (HIS36) and expression of regeneration markers [cytokeratin 19, hepatic growth factor (HGF)-α, and HGF-β] were determined by immunohistochemistry.

Results

The survival rate was 96.67% (1/30); one animal died. The mortality in the BDO group was 6% (1/18) and that in the control group was 0% (0/12). BDO resulted in a sharp increase of hepatocellular injury and cholestatic parameters on POD 2 with a rapid decline till POD 3. Significantly strongest activation of Kupffer cells and expression of proliferation markers were found until POD 5 after BDO.

Conclusion

The clip technique is a safe, cheap, and valid method for reversible biliary occlusion with an extremely low mortality.

Targeting Hepatic Fibrosis in Autoimmune Hepatitis

Hepatic fibrosis develops or progresses in 25 % of patients with autoimmune hepatitis despite corticosteroid therapy. Current management regimens lack reliable noninvasive methods to assess changes in hepatic fibrosis and interventions that disrupt fibrotic pathways. The goals of this review are to indicate promising noninvasive methods to monitor hepatic fibrosis in autoimmune hepatitis and identify anti-fibrotic interventions that warrant evaluation. Laboratory methods can differentiate cirrhosis from non-cirrhosis, but their accuracy in distinguishing changes in histological stage is uncertain. Radiological methods include transient elastography, acoustic radiation force impulse imaging, and magnetic resonance elastography. Methods based on ultrasonography are comparable in detecting advanced fibrosis and cirrhosis, but their performances may be compromised by hepatic inflammation and obesity. Magnetic resonance elastography has excellent performance parameters for all histological stages in diverse liver diseases, is uninfluenced by inflammatory activity or body habitus, has been superior to other radiological methods in nonalcoholic fatty liver disease, and may emerge as the preferred instrument to evaluate fibrosis in autoimmune hepatitis. Promising anti-fibrotic interventions are site- and organelle-specific agents, especially inhibitors of nicotinamide adenine dinucleotide phosphate oxidases, transforming growth factor beta, inducible nitric oxide synthase, lysyl oxidases, and C-C chemokine receptors types 2 and 5. Autoimmune hepatitis has a pro-fibrotic propensity, and noninvasive radiological methods, especially magnetic resonance elastography, and site- and organelle-specific interventions, especially selective antioxidants and inhibitors of collagen cross-linkage, may emerge to strengthen current management strategies.

Postoperative biological and clinical outcomes following uncomplicated pancreaticoduodenectomy

Backgrounds/Aims

The aim of this study was to describe clinical and biological changes in a group of patients who underwent pancreaticoduodenectomy (PD) without any complication during the postoperative period. These changes reflect the "natural history" of PD, and a deviation should be considered as a warning sign.

Methods

Between January 2000 and December 2009, 131 patients underwent PD. We prospectively collected and retrospectively analyzed demographic data, pathological variables, associated pathological conditions, and preoperative, intraoperative, and postoperative variables. Postoperative variables were validated using an external prospective database of 158 patients.

Results

The mean postoperative length of hospital stay was 20.3±4 days. The mean number of days until removal of nasogastric tube was 6.3±1.6 days. The maximal fall in hemoglobin level occurred on day 3 and began to increase after postoperative day (POD) 5, in patients with or without transfusions. The white blood cell count increased on POD 1 and persisted until POD 7. There was a marked rise in aminotransferase levels at POD 3. The peak was significantly higher in patients with hepatic pedicle occlusion (866±236 IU/L versus 146±48 IU/L; p<0.001). For both γ-glutamyl transpeptidase and alkaline phosphatase, there was a fall on POD1, which persisted until POD 5, followed with a stabilization. Bilirubin decreased progressively from POD 1 onwards.

Conclusions

This study facilitates a standardized biological and clinical pathway of follow-up. Patients who do not follow this recovery indicator could be at risk of complications and additional exams should be made to prevent consequences of such complications.

Morphological changes in the liver and kidneys of rats subjected to terminal ileum exclusion during obstructive cholestasis

PURPOSE

To investigate the effects of ileal exclusion on hepatic and renal morphology in extra-hepatic cholestasis.

METHODS

Twenty four rats were distributed into three groups. Group 1 (control) underwent laparotomy and laparorrhaphy. The animals in groups 2 and 3 underwent hepatic duct ligature and kept in cholestasis for four weeks. After this period, the rats in groups 2 and 3 underwent internal biliary derivation. In Group 3, the last ten centimeters of the terminal ileum were by passed and excluded. Four weeks later, histological and biochemical analysis were performed in all animals of the three groups.

RESULTS

In Group 1, no abnormalities regarding hepatic morphology were observed. All animals from groups 2 and 3 presented hepatic fibrosis. No difference was observed between the two groups. No morphological differences in renal histology could be identified among the three groups. There were differences in AST (p<0.05), ALT (p<0.05), direct bilirubin (p<0.05), ƔGT (p<0.05), urea (p<0.05) and creatinine (p<0.05) in Group 3 compared to control.

CONCLUSION

The distal ileum exclusion had no influence upon the hepatic and renal morphological alterations, and biochemical liver and kidney tests have worsened.

Changes in liver stiffness using acoustic radiation force impulse imaging in patients with obstructive cholestasis and cholangitis

BACKGROUND

Acoustic radiation force impulse imaging is used to assess stages of liver fibrosis. The aim of our study was to evaluate liver stiffness changes in patients with biliary obstruction with or without sclerosing cholangitis after biliary drainage.

METHODS

A total of 71 patients were enrolled in this prospective study (cohort N=51, control group N=20); 51 patients with obstructive cholestasis, indicated for endoscopic retrograde cholangiography, received stiffness measurement by acoustic radiation force impulse imaging before and 1-2 days after endoscopic retrograde cholangiography. Seventeen patients with obstructive cholestasis had primary or secondary sclerosing cholangitis. Forty one patients had a follow-up acoustic radiation force impulse imaging measurement after 3.0 ± 9.31 weeks.

RESULTS

In all patients with obstructive cholestasis, stiffness decreased significantly after biliary drainage (p<0.001). The main decrease was observed within 2 days after endoscopic retrograde cholangiography (1.92-1.57 m/s, p<0.001) and correlated with the decrease of bilirubin and alkaline phosphatase (p=0.04 and p=0.002, respectively). In patients with sclerosing cholangitis, the initial decrease of stiffness after biliary drainage was weaker than in those without (2.1-1.85 m/s vs. 1.81-1.43 m/s, p=0.016).

CONCLUSION

Acoustic radiation force impulse imaging elastography shows that liver stiffness is increased by biliary obstruction, and decreases after endoscopic retrograde cholangiography irrespective of the aetiology. In patients with sclerosing cholangitis the reduction in stiffness after biliary drainage is impaired.

Influence of distal ileum exclusion on hepatic and renal functions in presence of extrahepatic cholestasis

OBJECTIVE

To verify whether the ileal exclusion interferes with liver and kidney functional changes secondary to extrahepatic cholestasis.

METHODS

We studied 24 rats, divided into three groups with eight individuals each: Group 1 (control), Group 2 (ligation of the hepatic duct combined with internal biliary drainage), and Group 3 (bile duct ligation combined with internal biliary drainage and exclusion of the terminal ileum). Animals in Group 1 (control) underwent sham laparotomy. The animals of groups 2 and 3 underwent ligation and section of the hepatic duct and were kept in cholestasis for four weeks. Next, they underwent an internal biliary bypass. In Group 3, besides the biliary-enteric bypass, we associated the exclusion of the last ten centimeters of the terminal ileum and carried out an ileocolic anastomosis. After four weeks of monitoring, blood was collected from all animals of the three groups for liver and kidney biochemical evaluation (albumin, ALT, AST, direct and indirect bilirubin, alkaline phosphatase, cGT, creatinine and urea).

RESULTS

there were increased values of ALT, AST, direct bilirubin, cGT, creatinine and urea in rats from Group 3 (p < 0.05).

CONCLUSION

ileal exclusion worsened liver and kidney functions in the murine model of extrahepatic cholestasis, being disadvantageous as therapeutic procedure for cholestatic disorders.

Review article: The prevention and reversal of hepatic fibrosis in autoimmune hepatitis

BACKGROUND

Immunosuppressive treatment of autoimmune hepatitis can prevent or reverse hepatic fibrosis, but these anti-fibrotic effects are inconsistent secondary gains.

AIM

To describe the anti-fibrotic effects of current therapies for autoimmune hepatitis, discuss the pathogenic mechanisms of hepatic fibrosis that might be targeted by anti-fibrotic interventions, indicate the non-invasive diagnostic tests of hepatic fibrosis that must be validated in autoimmune hepatitis and to suggest promising treatment opportunities.

METHODS

Studies cited in PubMed from 1972 to 2013 for autoimmune hepatitis, hepatic fibrosis, cirrhosis, anti-fibrotic therapy and non-invasive tests of hepatic fibrosis were selected.

RESULTS

Hepatic fibrosis improves in 53-57% of corticosteroid-treated patients with autoimmune hepatitis; progressive fibrosis slows or is prevented in 79%; and cirrhosis may be reversed. Progressive hepatic fibrosis is associated with liver inflammation, and the inability to fully suppress inflammatory activity within 12 months is associated with progression to cirrhosis (54%) and death or need for liver transplantation (15%). Liver tissue examination remains the gold standard for assessing hepatic fibrosis, but laboratory and radiological tests may be useful non-invasive methods to measure the fibrotic response. Severe liver inflammation can confound radiological assessments, and the preferred non-invasive test in autoimmune hepatitis is uncertain. Individualised treatment adjustments and adjunctive anti-fibrotic therapies are poised for study in this disease.

CONCLUSIONS

The prevention and reversal of hepatic fibrosis are achievable objectives in autoimmune hepatitis. Strategies that evaluate individualised therapies adjusted to the rapidity and completeness of the inflammatory response, and the use of adjunctive anti-fibrotic interventions, must be evaluated.

Persistent fibrosis in the liver of choline-deficient and iron-supplemented L-amino acid-defined diet-induced nonalcoholic steatohepatitis rat due to continuing oxidative stress after choline supplementation

Nonalcoholic steatohepatitis (NASH) is characterized by combined pathology of steatosis, lobular inflammation, fibrosis, and hepatocellular degeneration, with systemic symptoms of diabetes or hyperlipidemia, all in the absence of alcohol abuse. Given the therapeutic importance and conflicting findings regarding the potential for healing the histopathologic features of NASH in humans, particularly fibrosis, we investigated the reversibility of NASH-related findings in Wistar rats fed a choline-deficient and iron-supplemented l-amino acid-defined (CDAA) diet for 12weeks, with a recovery period of 7weeks, during which the diets were switched to a choline-sufficient and iron-supplemented l-amino acid-defined (CSAA) one. Analysis showed that steatosis and inflammation were significantly resolved by the end of the recovery period, along with decreases in AST and ALT activities within 4weeks. In contrast, fibrosis remained even after the recovery period, to an extent similar to that in continuously CDAA-fed animals. Real-time reverse transcriptase-polymerase chain reaction, Western blot, and immunohistochemical investigations revealed that expression of some factors indicating oxidative stress (CYP2E1, 4-HNE, and iNOS) were elevated, whereas catalase and SOD1 were decreased, and a hypoxic state and CD34-positive neovascularization were evident even after the recovery period, although the fibrogenesis pathway by activated α-SMA-positive hepatic stellate cells via TGF-β and TIMPs decreased to the CSAA group level. In conclusion, persistent fibrosis was noted after the recovery period of 7weeks, possibly due to sustained hypoxia and oxidative stress supposedly caused by capillarization. Otherwise, histopathological features of steatosis and inflammation, as well as serum AST and ALT activities, were recovered.

Influence of biliary anastomosis on recovery from secondary biliary cirrhosis

OBJECTIVE

The influence of choledochoduodenostomy and choledochojejunostomy on the repair of hepatic lesions secondary to biliary obstruction is not well known. The aim of the present study was to compare the effects of choledochoduodenostomy and choledochojejunostomy on the recovery of these lesions in rats with biliary obstruction.

METHODS

Rats subjected to 4 weeks of biliary obstruction underwent choledochoduodenostomy (n=10) or choledochojejunostomy (n=10). The following variables were measured: total bilirubin, alkaline phosphatase, aminotransferases, and albumin. Hepatic mitochondrial energy metabolism was evaluated by calculating the respiratory control ratio and the oxidative phosphorylation index. Hepatic morphometry was used to estimate the mass of the hepatocytes, bile ducts, and fibrosis, as well as the hepatic stellate cell count.

RESULTS

After choledochoduodenostomy and choledochojejunostomy, there was a regression in cholestasis and a reduction in the oxidative phosphorylation index. However, the total bilirubin, alkaline phosphatase, albumin, and respiratory control ratio values improved only after choledochojejunostomy. The mass of the liver, spleen, and fibrosis was reduced after both choledochoduodenostomy and choledochojejunostomy, but the number of hepatic stellate cells increased. After choledochojejunostomy, the hepatic mass recovered completely, and the spleen mass was significantly reduced compared with that after choledochoduodenostomy. After both choledochoduodenostomy and choledochojejunostomy, enterobiliary reflux, biliary contamination, and an exacerbation in hepatic inflammation developed.

CONCLUSION

Choledochojejunostomy was more effective than choledochoduodenostomy, but both techniques induced enterobiliary reflux and biliary contamination, which may explain the maintenance of hepatic alterations, especially after choledochoduodenostomy.

The effects of L-arginine on liver damage in experimental acute cholestasis an immunohistochemical study

Obstructive jaundice damages critical functions in the liver. Nitric oxide modulation would influence liver damage induced by biliary obstruction, and little is known about it Acute cholestasis was induced by bile duct ligation (BDL) in two groups of male Sprague-Dawley rats. L-Arginine or serum physiologic was administered to treatment and control group. Histopathological and immunohistochemical iNOS expression was investigated in hepatic tissue. Plasma enzyme activities were increased in acute cholestasis, and that L-arginine treatment partially but significantly prevented the elevation of these markers of liver damage (P <  .05). Also histopathology scoring showed that the liver injury was prevented and immunohistochemical iNOS activity was increased significantly in L-arginine group (P <  .05). This study shows that, after 7 days of biliary obstruction, liver damage is well established and exogenous L-arginine treatment partially but significantly prevented the liver injury in acute cholestasis.

Animal models for the study of hepatic fibrosis

Animal models are being used for several decades to study fibrogenesis and to evaluate the anti-fibrotic potential of therapies and strategies. Although immensely valuable for our understanding of pathophysiological processes, they remain models and none of them reproduces a human disease. Each model (meaning stimulus, design, strain and species) displays specific characteristics in the nature of the pathogenesis, the topography and the evolution of fibrosis. We review here the most used as well as some newly described but potentially interesting models including models for studying biliary, immune, alcohol-induced, NASH-associated and viral fibrosis and provide insight on underlying disease processes and practical details. We attempted to delineate the benefits, advantages, limitations and drawbacks of those models. We also report the new opportunities provided by genetically engineered mice for tracking and manipulating cells that participate to fibrosis. Finally, we emphasize the importance of adapting study design to the question addressed.

Effects of carbon dioxide pneumoperitoneum on hepatic function in obstructive jaundice: an experimental study in a rat model

BACKGROUND AND AIMS

The physiology of the patient during laparoscopy differs from that of open surgery. Both pneumoperitoneum and obstructive jaundice impair the hepatic function, but the combined insult has not been previously examined. In this study, we aimed to investigate the effects of carbon dioxide (CO(2)) pneumoperitoneum on hepatic function in a rat model of obstructive jaundice.

METHODS

Forty-four male Sprague-Dawley rats were divided into four groups: group 1 (n = 10), sham-operated group; group 2 (n = 12), obstructive jaundice group; group 3 (n = 10), CO(2) pneumoperitoneum group; and group 4 (n = 12), obstructive jaundice and CO(2) pneumoperitoneum group. Common bile duct was ligated and divided in the obstructive jaundice groups. After 6 days, a 12-mmHg pneumoperitoneum was induced, maintained for 60 min, and released for 120 min. Blood samples were drawn for the measurement of white blood cell and platelet counts, serum liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], total bilirubin). Tissue samples were obtained for analyses of malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) levels. We evaluated the degree of liver injury on a grading scale from 0 to 4, histopathologically.

RESULTS

Pneumoperitoneum after biliary obstruction resulted in an increase in AST and ALT levels and a decrease in white blood cell and platelet counts. However, changes in liver tissue MDA, GSH, and SOD levels did not correlate with the changes in AST and ALT levels and white blood cell and platelet counts. After sham operation with pneumoperitoneum, the GSH levels in liver homogenate were significantly decreased in the group 3 when compared to the group 2. On the other hand, obstructive jaundice itself caused significant reduction in the SOD activity of liver homogenate in comparison to the group 3. Histopathologically, sinusoidal congestion and vacuolization were more severe in the group 3.

CONCLUSIONS

Alterations in hepatic function occur in pneumoperitoneum applied jaundiced subjects. However, there were no statistically significant differences between the groups 2 and 4 with regard to white blood cell and platelet counts, serum liver enzymes including AST, ALT, and total bilirubin values, MDA and GSH levels and SOD activity of liver homogenate, and histologic damage. These results indicate that there is no additional risk on liver function associated with pneumoperitoneum performed in obstructive jaundice.

Evaluation of the mitochondrial respiration of cardiac myocytes in rats submitted to mechanical bile duct obstruction

PURPOSE

The objective of the present study was to evaluate the capacity of the myocardium for energy production by the analysis of mitochondrial respiration in rats with jaundice submitted to bile duct ligature.

METHODS

Sixteen male Wistar rats were divided into 2 Groups: Group SO submitted to nontherapeutic laparotomy (sham operation) and Group IC (icteric group) submitted to bile duct ligature. After 7 days, laparotomy was again performed in all animals for cardiac muscle extraction and analysis. Mitochondrial oxygen consumption was determined by stage 3 velocity and stage 4 velocity. The respiratory control ratio (RCR) was obtained by the ratio of stage 3 to stage 4 velocity. Statistical analysis was performed by the Mann-Whitney test, with the level of significance set at 5% (p<0.05).

RESULTS

Statistical analysis revealed a significant drop in oxygen consumption during stage 3 mitochondrial respiration in group IC compared with SO, whereas the values obtained during stage 4 were basically identical for the two groups. Likewise, RCR values exhibited a significant reduction.

CONCLUSION

The cellular respiration of the "jaundiced heart" is depressed. This was demonstrated by the reduced capacity of cardiac mitochondria to consume oxygen and synthesize ATP, supporting the idea of a latent cardiac impairment responsible for the hemodynamic decompensation occurring during cholestasis.

Regression of fibrosis in paediatric autoimmune hepatitis: morphometric assessment of fibrosis versus semiquantiatative methods

Background

Regression of hepatic fibrosis in patients with autoimmune hepatitis (AIH) has been described in response to immunosuppressive therapy. These studies, however, besides being few in number, were conducted on adult populations. Our aim was to assess the regression of hepatic fibrosis, using morphometric assessment of fibrosis versus semi-quantitative methods, in children with AIH who achieved clinical and biochemical remission. Thirteen patients who achieved clinical and biochemical remission were included in the study, out of 62 children with AIH. Repeat biopsy was performed after 6 to 12 months of clinical and biochemical remission. Morphometric assessment of fibrosis was performed and correlated with METAVIR and Ishak semi-quantitative scores.

Results

The study group included eight male and five female patients. The median age at presentation was 4 years (range 2 to 12 years). The mean duration of treatment was 22 ± 7.3 months, and the mean interval between biopsies was 26.2 ± 6.5 months. Following therapy, there was significant reduction in aspartate aminotransferase, ALT and IgG levels as well as improvement of necroinflammation. The mean fibrosis scores were significantly decreased from 4.5 ± 1.19 and 2.9 ± 0.7 before therapy to 2.7 ± 1.16 and 2 ± 0.8 after treatment as assessed by Ishak and METAVIR scores, respectively (P = 0.001 and 0.004). The mean morphometric assessment of fibrosis before treatment was 20% ± 9.7 and following therapy it decreased to 5.6% ± 3.9 (P = 0.000).

Conclusion

Significant regression of fibrosis in paediatric AIH could occur with current therapeutic regimens. Morphometric assessment of fibrosis is more sensitive than semi-quantitative methods to identify changes in fibrosis.

Liver histology in benign biliary stricture: fibrosis to cirrhosis . . . and reversal?

BACKGROUND

Secondary biliary cirrhosis is a potential complication of post-cholecystectomy bile duct stricture (PCBDS). This study addresses the factors that determine the severity of pathological changes on liver biopsy and the correlation with long-term outcome following repair.

METHODS

Liver biopsies obtained at surgery for repair of PCBDS in 71 patients were reviewed and pathological changes were scored from 0 to 3. Patients with fibrosis score 0-2 were categorized as the non-cirrhotic group and those with score 3 (secondary biliary cirrhosis) were categorized as the cirrhotic group. Clinical and biochemical parameters, stricture type and outcome were analyzed by univariate and multivariate analysis for correlation with degree of fibrosis. Follow-up liver biopsies (3-60 months) after stricture repair were obtained in five patients.

RESULTS

There were 58 patients in the non-cirrhotic group and 13 in the cirrhotic group. On univariate analysis, portal hypertension and prolonged injury-repair duration correlated with secondary biliary cirrhosis. Patients with a fair outcome in the cirrhotic group (4/13) had derangements in liver function tests but had patent biliary enteric anastomosis on evaluation. Of the five patients in whom liver biopsies were obtained at follow up, two had regression, two were static, and one had progression.

CONCLUSION

All patients with PCBDS had varying degrees of fibrosis. Prolonged injury-repair interval and portal hypertension were the important parameters correlating with secondary biliary cirrhosis. Early repair of biliary stricture is recommended to prevent liver fibrosis. A successful relief of biliary obstruction may halt and/or reverse pathological changes in the liver.

Effect of biliary obstruction and internal biliary drainage on hepatic cytochrome P450 isozymes in rats

AIM: To investigate the total cytochrome P450 (CYP) content, microsomal mixed-function oxidase (MFO) activity, and expression of mRNAs for various CYP isozymes in a simple rat model of reversible obstructive jaundice.

METHODS: Obstructive jaundice was created in male rats by causing bile duct obstruction with polyester tape. In another group of rats, bile duct obstruction was followed by internal biliary drainage after releasing the tape. The expression of various CYP isozyme mRNAs was semi-quantitatively assessed by competitive RT-PCR.

RESULTS: The total CYP content and microsomal MFO activity showed a significant decrease after biliary obstruction, but returned to respective control levels after biliary drainage. A marked reduction in the expression of CYP1A2, 2B1/2, 2C11, 2E1, 3A1, and 3A2 mRNA was detected during biliary obstruction, while expression increased significantly toward the control level after biliary drainage. Although expression of CYP4A1 mRNA showed no reduction during biliary obstruction, it still increased significantly after biliary drainage.

CONCLUSION: These results suggest that not only obstructive jaundice, but also the subsequent internal biliary drainage may affect regulatory medications of the synthesis of individual CYP isozymes differently.

Management of patients of postcholecystectomy benign biliary stricture complicated by portal hypertension

BACKGROUND

Portal hypertension (PHT) is seen in 15% to 20% of patients with postcholecystectomy benign biliary stricture (BBS). Preliminary portosystemic shunt (PSS) has been recommended to reduce the morbidity and mortality associated with direct stricture repair. Single-center experience of primary repair without preceding PSS in patients of BBS with PHT and a patent portal vein is presented.

METHODS

A retrospective study of 13 patients with postcholecystectomy BBS with PHT managed between January 1, 2000 and March 31, 2006.

RESULTS

Roux-en-Y hepaticojejunostomy was performed in 11 patients. There was no major morbidity or mortality with minor complications seen in 3 patients. The median duration of surgery was 3.5 hours with a median blood loss of 300 mL. All patients were asymptomatic at a median follow-up of 17 months.

CONCLUSION

Hepaticojejunostomy can be performed safely without prior portal decompression in patients with postcholecystectomy BBS complicated by PHT but with a patent portal vein.

Effect of preoperative endoscopic biliary drainage on infectious morbidity after pancreatoduodenectomy: a case-control study

BACKGROUND

The utility of preoperative endoscopic biliary drainage (PEBD) in jaundiced patients before pancreatoduodenectomy (PD) is still debated. This is in part due to the heterogeneity of the studied population, including different tumor location, drainage techniques, and surgical procedures. The aim of the current study was to report the influence of PEBD on postoperative infectious morbidity of PD.

MATERIALS AND METHODS

Between January 1996 and December 2004, 124 patients underwent a PD and 28. Twenty-eight (22.6%) of these patients underwent a PEBD. This group of patients was matched to 28 control patients who underwent PD without PEBD during the same period. The 2 groups were matched for age, sex, indication of surgery, and serum bilirubin levels.

RESULTS

The specific morbidity of PEBD before surgery was 10.7% (n = 3). The postoperative overall morbidity, medical morbidity, and surgical morbidity rates were not different between the 2 groups. At the time of surgery, 89.3% (n = 25) of the patients in the PEBD group had positive bile culture in comparison to 19.4% (n = 4) in the control group (P < .001). The number of patients with 1 or more infectious complications was higher in the PEBD group (50%; n = 14) than in the control group (21.4%; n = 6) (P = .05).

CONCLUSIONS

Before PD, PEBD should be routinely avoided whenever possible in patients with potentially resectable pancreatic and peripancreatic lesions. In patients with cholangitis, requiring extensive preoperative assessment (such as liver biopsy) or neoadjuvant treatment, PEBD might still be indicated.

Evaluation of hepatobiliary excretion and enterobiliary reflux in rats with biliary obstruction submitted to bilioduodenal or biliojejunal anastomosis

Bilioduodenal and biliojejunal anastomoses are effective for the treatment of biliary obstruction. The objective of this study was to compare the effects of these anastomoses on hepatobiliary excretion and enterobiliary reflux. Enterobiliary reflux and biliary excretion were evaluated respectively after oral administration of technetium ((99m)Tc) in combination with sodium phytate and intravenous infusion of (99m)Tc with diisopropyl-iminodiacetic acid. Enterobiliary reflux occurred to an equal degree in the bilioduodenal and biliojejunal groups. Maximum hepatic activity time (T(max)) and radiotracer clearance half-time (T(1/2)) were similar in both groups. However, when compared with that found for the sham-operated group, T(max), and T(1/2) were higher in the biliojejunal group (P = 0.02 and P = 0.01, respectively). Histopathological analysis showed marked reduction in ductal proliferation in both groups. These data undermine the theoretical advantages attributed to biliojejunal anastomosis and further the understanding of the pathophysiology of cholangitis that occurs even with patent anastomosis.

Complex bile duct injuries: management

Laparoscopic cholecystectomy is the present treatment of choice for patients with gallbladder stones, despite its being associated with a higher incidence of biliary injuries compared with the open procedure. Injuries occurring during the laparoscopic approach seem to be more complex. A complex biliary injury is a disease that is difficult to diagnose and treat. We considered complex injuries: 1) injuries that involve the confluence; 2) injuries in which repair attempts have failed; 3) any bile duct injury associated with a vascular injury; 4) or any biliary injury in association with portal hypertension or secondary biliary cirrhosis. The present review is an evaluation of our experience in the treatment of these complex biliary injuries and an analysis of the international literature on the management of patients.

Role of alphavbeta6 integrin in acute biliary fibrosis

Acute biliary obstruction leads to periductal myofibroblasts and fibrosis, the origin of which is uncertain. Our study provides new information on this question in mice and humans. We show that bile duct obstruction induces a striking increase in cholangiocyte alphavbeta6 integrin and that expression of this integrin is directly linked to fibrogenesis through activation of transforming growth factor beta (TGF-beta). Administration of blocking antibody to alphavbeta6 significantly reduces the extent of acute fibrosis after bile duct ligation. Moreover, in beta6-null mice subjected to the injury, fibrosis is reduced by 50% relative to that seen in wild-type mice, whereas inflammation occurs to the same extent. The data indicate that alphavbeta6, rather than inflammation, is linked to fibrogenesis. It is known that alphavbeta6 binds latent TGF-beta and that binding results in release of active TGFbeta. Consistent with this, intracellular signaling from the TGFbeta receptor is increased after bile duct ligation in wild-type mice but not in beta6(-/-) mice, and a competitive inhibitor of the TGFbeta receptor type II blocks fibrosis to the same extent as antibody to alphavbeta6. In a survey of human liver disease, expression of alphavbeta6 is increased in acute, but not chronic, biliary injury and is localized to cholangiocyte-like cells.

CONCLUSION

Cholangiocytes respond to acute bile duct obstruction with markedly increased expression of alphavbeta6 integrin, which is closely linked to periductal fibrogenesis. The findings provide a rationale for the use of inhibitors of alphavbeta6 integrin or TGFbeta for down-regulating fibrosis in the setting of acute or ongoing biliary injury.

The beneficial effect of aspirin and enoxaparin on fibrosis progression and regenerative activity in a rat model of cirrhosis

The aim of this study was to examine the effect of the antithrombotic drugs aspirin and enoxaparin on fibrosis progression and regenerative activity in a rat model of liver cirrhosis and to determine if these two drugs are beneficial in animals with advanced fibrosis or with established cirrhosis undergoing partial hepatectomy. Thioacetamide-induced cirrhotic rats received saline (N=10), aspirin (N=7), or enoxaparin (N=11) for a 5-week treatment period. Hepatic fibrosis was assessed according to METAVIR score. Liver regeneration was monitored using PCNA immunostaining. Compared to untreated cirrhotic controls, a significant improvement in fibrosis grade was observed in the aspirin (43%; chi(2)=54, P<0.001) and enoxaparin (36%; chi(2)=43, P<0.001) treated groups. Postoperatively, total serum bilirubin levels were lower in the aspirin (1.4+/-0.18 mg/dl; P<0.01) and enoxaparin (1.8+/-0.35 mg/dl; P<0.05)-treated groups compared to untreated cirrhotic controls (3.2+/-0.6 mg/dl). Hepatic regenerative activity was significantly improved in the aspirin group (57.3%+/-6.8%, versus 34.2%+/-7.2% in untreated cirrhotic controls; P<0.01) but unchanged in the enoxaparin group. We conclude that aspirin and enoxaparin hold promise as a useful therapy for patients with extensive fibrosis.

Bile duct injuries: management of late complications

BACKGROUND

Laparoscopic cholecystectomy is the treatment of choice for gallbladder stones. In the current study, this approach was associated with a higher incidence of biliary injuries. The authors evaluate their experience treating complex biliary injuries and analyze the literature.

METHODS

In a 15-year period, 169 patients with bile duct injuries (BDIs) resulting from open and laparoscopic cholecystectomies were treated. The patients were retrospectively evaluated through their records. Biliary injury and associated lesions were evaluated with imaging studies. Surgical management included therapeutic endoscopy, percutaneous interventions, hepaticojejunostomy, liver resection, and liver transplantation. Postoperative outcome was recorded. Survival analysis was performed with G-Stat and NCSS programs using the Kaplan-Meier method.

RESULTS

Of the 169 patients treated for BDIs, 148 were referred from other centers. The injuries included 115 lesions resulting from open cholecystectomy and 54 lesions resulting from laparoscopic cholecystectomy. A total of 110 patients (65%) fulfilled the criteria for complex injuries, 11 of whom met more than one criteria. Injuries resulting from laparoscopic and open cholecystectomies were complex in 87.5% and 72% of the patients, respectively. The procedures used were percutaneous transhepatic biliary drainage for 30 patients, hepaticojejunostomy for 96 patients, rehepaticojejunostomy for 16 patients, hepatic resection for 9 patients, and liver transplantation projected for 18 patients. Hepaticojejunostomy was effective for 85% of the patients. The mean follow-up period was 77.8 months (range, 4-168 months). The mortality rate for noncomplex BDI was 0%, as compared with the mortality rate of 7.2% (8/110) for complex BDI. Mortality after hepatic resection was nil, and morbidity was 33.3%. The actuarial survival rate for liver transplantation at 1 year was 91.7%.

CONCLUSIONS

Complex BDIs after laparoscopic cholecystectomy are potentially life-threatening complications. In this study, late complications of complex BDIs appeared when there was a delay in referral or the patient received multiple procedures. On occasion, hepatic resections and liver transplantation proved to be the only definitive treatments with good long-term outcomes and quality of life.

Direct and indirect evidence for the reversibility of cirrhosis

The aim of this study was to assess the reversibility of cirrhosis after therapy in a large series of patients with cirrhosis from various etiologies. We performed a retrospective study of 113 patients with biopsy-proven cirrhosis who underwent specific therapy and follow-up biopsies. Two pathologists performed blinded analyses of indirect biochemical and morphological signs of cirrhosis. Fourteen (12.4%) of the 113 cirrhotic patients had biopsy-proven disappearance of cirrhosis, defined as a decrease of 2 or greater in their METAVIR fibrosis score: 8 were related to hepatitis C virus, 3 to hepatitis B virus, and 3 to autoimmune cirrhosis. Necro-inflammatory activity decreased from 2.4 +/- 0.65 to 0.85 +/- 0.9 (P = .004), and fibrosis from 4 to 1.7 +/- 0.61 (P = .001). Prothrombin time (n = 1), platelet count (n = 2), serum albumin level (n = 2), and ultrasound abnormalities (n = 6) normalized in patients who had initial abnormalities. Hyaluronic acid and procollagen type III serum level decreased in all. In the 11 patients with regression of viral cirrhosis, 2 were nonresponders and 9 were responders, including 2 relapsers. The 3 patients with regressive autoimmune cirrhosis were complete responders to immunosupressive therapy. Using repeated liver biopsies, clinicobiochemical, radiologic, and endoscopic tests, we provide evidence for potential reversibility of cirrhosis after long-lasting suppression of the necro-inflammatory activity of liver disease.

Reversibility of hepatic fibrosis in treated genetic hemochromatosis: a study of 36 cases

The current study was undertaken to assess whether fibrosis could regress under venesection therapy in patients with C282Y homozygous genetic hemochromatosis. The 36 patients studied were recruited from a subfile of our database consisting of 125 C282Y homozygotes with either severe fibrosis or cirrhosis (F3 or F4 fibrosis stage, respectively, according to the METAVIR grading system). The second liver biopsy was performed for management of liver cancer, extrahepatic surgery, or assessment of liver fibrosis. All paired biopsies were reviewed by two pathologists without knowledge of clinical data. Among the 13 patients who had F3 fibrosis on their initial liver biopsy, 3 had F0, 6 had F1, and 2 had F2 on their second liver biopsy. Among the 23 patients with cirrhosis on their initial liver biopsy, 1 had F0, 4 had F1, 3 had F2, and 2 had F3 on their second liver biopsy. When defining regression of fibrosis as a decrease of at least 2 METAVIR units, fibrosis regressed in 9 of 13 (69%) F3 and in 8 of 23 (35%) F4. When the ratio of gammaglobulins (g/L) to (platelets [n/mm(3)] x prothrombin activity [%]) was greater than 7.5, fibrosis never regressed. In conclusion, these data extend the concept of regression of fibrosis to patients with treated genetic hemochromatosis and suggest that some simple biochemical tests would be predictive of further regression of fibrosis as a result of venesection therapy. If confirmed on larger series, this could modify the ultrasound screening policy of hepatocellular carcinoma in genetic hemochromatosis.

Estrogens maintain bile duct mass and reduce apoptosis after biliodigestive anastomosis in bile duct ligated rats

BACKGROUND/AIMS

Disapperacence of bile ducts (ductopenia) represents the terminal, common stage of human cholangiopathies, and estrogens exert a major role in stimulating cholangiocyte proliferation. We thus evaluated whether estrogen administration protect from the bile duct loss induced by the biliary-digestive diversion in bile duct ligated (BDL) rats.

METHODS

After 3 weeks of BDL, rats were subjected to biliary-digestive diversion and treated with daily injections of 17beta-estradiol or a control solution.

RESULTS

Both after 7 and 14 days from the biliary-digestive diversion a marked increase of the number of apoptotic cholangiocytes was observed. In contrast, 17beta-estradiol significantly reduced cholangiocyte apoptosis. 17beta-estradiol also prevented the biliary-digestive diversion-induced loss of PCNA-positive cholangiocytes and of the bile duct mass. Biliary-digestive diversion determined a marked reduction of ERK1/2 phopsphorylation in cholangiocytes that was reversed by the administration of 17beta-estradiol.

CONCLUSIONS

This study indicates that estrogens prevent the increase of cholangiocyte apoptosis and loss of cholangiocyte proliferation induced by the biliary-digestive diversion in the BDL rat. In parallel, 17beta-estradiol also enhanced ERK1/2 phosphorylation, which is instead strongly reduced by the biliary-digestive diversion. These novel findings suggest that estrogens could prevent the evolution of cholangiopathies toward ductopenia.

Efeito da ressecção do íleo terminal na fibrose hepática secundária à ligadura do ducto hepático comum em ratas

OBJETIVO: A evolução para fibrose hepática e, posteriormente, para cirrose são fatos bem estabelecidos na colestase extra-hepática prolongada. A despeito dos avanços nos métodos diagnósticos e terapêuticos, essas complicações continuam de difícil solução, principalmente, quando não é possível reverter a causa da colestase. Neste trabalho, procurou-se verificar, em modelo experimental de colestase pela ligadura do ducto hepático comum, se a exclusão do íleo terminal reduziria o desenvolvimento de fibrose hepática. Não houve abordagem direta da causa da colestase, mas atuou-se nos mecanismos de secreção e regulação do fluxo biliar êntero-hepático. MÉTODO: Foram utilizadas trinta e cinco ratas Wistar, distribuídas em três grupos: Grupo 1, apenas laparotomia e laparorrafia; Grupo 2, ligadura do ducto hepático comum; Grupo 3, ligadura do ducto hepático comum associada a ressecção do íleo terminal, com reconstrução do trânsito intestinal, por meio de anastomose íleo-cólon ascendente. Após trinta dias, os animais foram mortos e o fígado de cada rata foi retirado, para a análise histológica. RESULTADOS: Os resultados foram submetidos a análise estatística pelo teste de Kuskal-Wallis, com nível de significância de 95 % (p < 0,05). Verificou-se que houve fibrose hepática nos grupos 2 e 3, porém sem cirrose. O Grupo 3 apresentou fibrose menos acentuada que o Grupo 2. CONCLUSÕES: Conclui-se que a ressecção do íleo terminal associa-se a menor alteração histológica, no fígado de ratas, decorrente de colestase obstrutiva.

Halofuginone can worsen liver fibrosis in bile duct obstructed rats

BACKGROUND/AIMS

Halofuginone (HF) is an antifibrotic agent in rat models of liver fibrosis caused by repetitive intoxications. A beneficial effect of HF on a biliary type of liver fibrosis has not been proven yet.

METHODS

Bile duct-obstructed rats were given HF from the moment of obstruction onwards and compared with no treatment. After 3 weeks, respectively, 6 weeks, aminopyrine breath test (ABT) and haemodynamic measurements including of portal pressure were carried out. Liver pieces were taken for Sirius red quantitative scoring, as well as for semiquantitative determinations of collagen type I and III RNA levels.

RESULTS

ABT was significantly worse in HF-treated rats as compared with no treatment (P=0.02). Haemodynamic data and collagen type I and III determinations were not significantly different between groups. Biliary fibrosis scores were significantly higher in HF-treated rats as compared with no treatment (P=0.03). More Sirius red staining was associated with more proliferation of bile ductules.

CONCLUSIONS

HF may worsen biliary fibrosis. This contrasts sharply with antifibrotic effects in other models of liver fibrosis. Distinctive cellular mechanisms in biliary fibrosis may explain this discrepancy. One should be cautious for chronic application of HF in man with cholestasis.

Improved effects of viral gene delivery of human uPA plus biliodigestive anastomosis induce recovery from experimental biliary cirrhosis

Gene therapy may represent a new avenue for the development of multimodal treatment for diverse forms of cirrhosis. This study explores the potential benefits of combining adenovirus-mediated human urokinase-plasminogen activator (AdHuPA) gene delivery and biliodigestive anastomosis to enhance the therapeutic efficacy of each treatment alone for cholestatic disorders resulting in secondary biliary cirrhosis. In an experimental model of secondary biliary cirrhosis, application of 6 x 10(11) vp/kg AdHuPA adenovirus vector resulted in 25.8% liver fibrosis reduction and some improvement in liver histology. The relief of bile cholestasis by a surgical procedure (biliodigestive anastomosis) combined with AdHuPA hepatic gene delivery rendered a synergistic effect, with a substantial 56.9 to 42.9% fibrosis decrease. AdHuPA transduction resulted in clear-cut expression of human uPA protein detected by immunohistochemistry and induction of up-regulation in the expression of metalloproteinases MMP-3, MMP-9, and MMP-2. Importantly, functional hepatic tests, specifically direct bilirubin, were improved. Also, hepatic cell regeneration, rearrangement of hepatic architecture, ascites, and gastric varices improved in cirrhotic rats treated with AdHuPA but not in counterpart AdGFP cirrhotic animals. We believe this might represent a novel therapeutic strategy for human cholestatic diseases.

Decreased fibrosis during corticosteroid therapy of autoimmune hepatitis

BACKGROUND/AIMS

Reduction in hepatic fibrosis and reversibility of cirrhosis has been described in chronic liver disease. Our goal was to determine changes in fibrosis and the frequency of histological cirrhosis in corticosteroid-treated autoimmune hepatitis (AIH).

METHODS

Three hundred twenty-five liver specimens from 87 treated patients were reviewed in batch under code by one pathologist and graded by the Ishak method.

RESULTS

Fibrosis scores improved (3.4+/-0.2 versus 2.6+/-0.2, P=0.0002) during 63+/-6 months, and histological activity indices decreased concurrently (6.8+/-0.5 versus 2.1+/-0.2, P<0.0001). Fibrosis scores improved in 46 patients (53%) during 57+/-7 months and did not progress in 23 patients during 62+/-12 months. The fibrosis score improved more commonly in patients who had improvement in the histological activity indices than in others (61 versus 32%, P=0.02), and the frequency of histological cirrhosis decreased from 16% (14 patients) to 11% (10 patients).

CONCLUSIONS

Fibrosis commonly improves or does not progress during corticosteroid therapy of AIH, and histological cirrhosis may disappear. Improvements in fibrosis are associated with suppression of inflammatory activity. Improvement or prevention of fibrosis may be a common but unheralded advantage of corticosteroid therapy.

Hepatocellular apoptosis after hepatectomy in obstructive jaundice in rats

AIM: To investigate the hepatocellular apoptosis after hepatectomy in obstructive jaundice and biliary decompression rats.

METHODS: After bile duct ligation for 7 days, rats were randomly divided into OB group in which the rats underwent 70% hepatectomy, OB-CD group in which the rats underwent hepatectomy accompanied by choledochoduodenostomy, CD-Hx group in which the rats underwent choledochoduodenostomy and then received 70% hepatectomy on the fifth day after biliary decompression. The control group (Hx group) only underwent hepatectomy.

RESULTS: The level of total serum bilirubin and serum enzymes was significantly lower in CD-Hx group than in OB-CD and OB groups on day 1, 3 and 5 after hepatectomy. The apoptotic index was significantly lower in CD-Hx group than in OB-CD and OB groups on day 3 and 5. The oligonucleosomal DNA fragments and Caspase-3 activity were also lower in CD-Hx group than in OB-CD and OB groups 3 days after hepatectomy, without differences between CD-Hx and Hx groups.

CONCLUSION: Hepatocellular apoptosis plays vital roles in jaundice rats, and biliary decompression is more effective in treatment of patients with severe jaundice before operation.

Role of apoptosis in the remodeling of cholestatic liver injury following release of the mechanical stress

It has been known for a long time that portal fibrosis consecutive to experimental common bile duct ligation is reversible following obstacle removal, but the mechanisms involved remain unknown. We have studied the effect of bilioduodenal anastomosis and of simple biliary decompression on the remodeling of the lesion in bile duct-ligated rats. Rats were subjected to common bile duct ligation for 7 days or 14 days. Bilioduodenal anastomosis was performed after 14 days of bile duct ligation and animals sacrificed at intervals. In other animals, after 7 days or 14 days of ligation, the common bile duct was merely decompressed by bile aspiration and animals sacrificed 24 h later. Collagen deposition, alpha-smooth muscle actin expression and apoptosis were evaluated. Bile was collected and the bile acid profile assessed. After anastomosis, collagen deposition and alpha-smooth muscle actin expression decreased and were back to control values after 7 days. These parameters remained practically unchanged 24 h after biliary decompression. Bile duct ligation by itself induced apoptosis of some fibroblastic and bile ductular cells after 7 days; this was back to normal after 14 days. After anastomosis or decompression, apoptosis of both fibroblastic and bile ductular cells increased greatly and was accompanied by ultrastructural features of extracellular matrix degradation. Total bile acid content decreased after common bile duct ligation, the proportion of dihydroxylated bile acids decreasing and that of trihydroxylated bile acids increasing. Biliary decompression and anastomosis did not modify total concentration and composition of the biliary bile acid pool. In summary, we show that mere biliary decompression, by relieving the mechanical stress, is as effective as bilioduodenal anastomosis to induce apoptosis of portal cells that likely triggers portal fibrosis regression.

Impaired ketogenesis is a major mechanism for disturbed hepatic fatty acid metabolism in rats with long-term cholestasis and after relief of biliary obstruction

BACKGROUND/AIMS

Rats with long-term cholestasis have reduced ketosis of unknown origin.

METHODS

Fatty acid metabolism was studied in starved rats with biliary obstruction for 4 weeks (bile duct ligated rats = BDL rats), and 3, 7, 14, 28 and 84 days after reversal of biliary obstruction by Roux-en-Y anastomosis (RY rats), and in sham-operated control rats.

RESULTS

BDL rats had reduced beta-hydroxybutyrate concentrations in plasma (0.25 +/- 0.10 vs. 0.75 +/- 0.20 mmol/l) and liver (2.57 +/- 0.20 vs. 4.63 +/- 0.61 micromol/g) which increased after restoring bile flow. Hepatic expression and activity of carnitine palmitoyltransferase I (CPT I) or CPT II were unaffected or decreased in BDL rats, respectively, and increased after restoring bile flow. Oxidative metabolism of different substrates by isolated liver mitochondria and activation of palmitate were reduced in BDL rats and recovered 7-14 days after restoring bile flow. Ketogenesis was decreased in mitochondria from BDL rats and recovered 3 months after restoring bile flow. Both mRNA and protein expression of hydroxymethylglutaryl-coenzyme A synthase (HMG-CoA synthase), the rate-limiting enzyme of ketogenesis, was reduced in livers of BDL rats and increased after reversing biliary obstruction.

CONCLUSIONS

In BDL rats, impairment of hepatic fatty acid metabolism is multifactorial. After reversing biliary obstruction, reduced activity of HMG-CoA synthase is the major factor.

Hepatic and skeletal muscle glycogen metabolism in rats with short-term cholestasis

BACKGROUND/AIMS

To study the effect of short-term cholestasis on glycogen metabolism.

METHODS

Rats were bile duct ligated (BDL) for 4 or 8 days and compared to sham-operated control rats pair-fed to BDL (pair-fed CON) or fed ad libitum (ad libitum-fed CON).

RESULTS

Four days after surgery, the hepatic glycogen content was 21.6+/-7.6 mg/g in BDL, 21.2+/-8.5 mg/g in pair-fed CON and 72.9+/-7.7 mg/g in ad libitum-fed CON, respectively. Eight days after surgery, the hepatic glycogen content was reduced in BDL as compared to pair-fed (31.2+/-8.9 vs. 59.1+/-5.4 mg/g) or ad libitum-fed CON (58.3+/-4.7 mg/g). Similar findings were obtained with the glycogen content expressed per ml hepatocytes or per liver. Histological analysis of BDL livers showed that most hepatocytes were affected. As compared to CON, activities and mRNA levels of glycogen synthase and phosphorylase were reduced in BDL, whereas plasma glucagon and endotoxin levels were increased at both time points. In contrast to liver, skeletal muscle glycogen metabolism remained unaffected.

CONCLUSIONS

While reduced intake of food explains the decrease in the hepatic glycogen stores in BDL and pair-fed CON 4 days after surgery, reduced glycogen synthesis, possibly related to endotoxinemia, is the most probable cause of the decrease in the hepatic glycogen content in BDL 8 days after surgery.

Selective versus total drainage for biliary obstruction in the hepatic hilus: an experimental study

BACKGROUND

Controversy exists as to whether selective biliary drainage (SBD) or total biliary drainage (TBD) is preferable as a preoperative procedure before extended hemihepatectomy for hilar cholangiocarcinoma, especially with regard to the functional reserve of the future remnant liver.

METHODS

SBD or TBD was performed after 1 week of total biliary obstruction in rats. In SBD, the biliary trees of the left lobes (approximately 70% of the liver) were kept obstructed, whereas the right lobes were drained selectively. Mitochondrial function and microsomal cytochrome content were examined before and 1, 2, and 4 weeks after drainage.

RESULTS

The right lobes weighed significantly more after SBD than after TBD. There were no significant differences in mitochondrial function between the two groups. The microsomal cytochrome content per milligram of microsomal protein significantly decreased 1 week after biliary obstruction and then recovered to a similar extent after SBD and TBD in the right lobes. However, the total microsomal cytochrome content (nanomoles per 100 g body weight) and the overall rate of mitochondrial adenosine triphosphate synthesis (mmoles per minute per 100 g of body weight) in the right lobes 4 weeks after SBD were significantly greater than those after TBD.

CONCLUSIONS

SBD is superior to TBD with regard to the functional reserve of the future remnant liver.

Characterisation of portal hypertension models by microspheres in anaesthetised rats: a comparison of liver flow

Several portal hypertensive animal models are available and frequently used for haemodynamic studies. The portal venous inflows, measured with microspheres in pentobarbital anaesthetised rats, are compared here. The partial portal vein ligation model is characterised by a high portal venous inflow, together with extensive portal systemic shunting, at the cost of portal sinusoidal flow. In carbon tetrachloride-induced micronodular cirrhosis, portal sinusoidal flow, which reaches liver parenchyma, is high, and this is more pronounced in the presence of ascites. In bile duct ligation and excision-induced cirrhosis, an increase in liver weight was not equally followed by an increase in portal sinusoidal flow, pointing to a relatively underperfused liver.

Regression of liver fibrosis after biliary drainage in patients with chronic pancreatitis and stenosis of the common bile duct

BACKGROUND

Chronic obstruction of the common bile duct may cause hepatic fibrosis and secondary biliary cirrhosis.

METHODS

We studied liver-biopsy specimens from 11 patients with chronic stenosis of the common bile duct due to chronic pancreatitis; all the patients had undergone liver biopsy before or at the time of surgical biliary decompression and underwent a subsequent liver biopsy for various clinical reasons. The patients were followed as part of a prospective study of 501 patients who had been treated for chronic pancreatitis. Two pathologists, who were unaware of the sequence of specimens, graded fibrosis on a scale of 0 (none) to 3 (cirrhosis).

RESULTS

The 11 patients were all men. Chronic pancreatitis was due to alcohol abuse in 10 of the men; 1 had idiopathic disease. The median age at diagnosis was 38 years. The median interval between the first and second liver biopsies was 2.5 years (range, 0.3 to 9.0). The two patients who had restenosis of the biliary anastomosis were excluded from the analysis of fibrosis. In the group of nine patients without restenosis, the second specimen showed significant improvement in fibrosis (P=0.01). The fibrosis improved by two grades in two patients and by one grade in four patients; in three patients, the grade did not change. The pathologists agreed on the grading of specimens from 10 of the 11 patients.

CONCLUSIONS

In patients with chronic pancreatitis and stenosis of the common bile duct, liver fibrosis may regress after biliary drainage.

Effect of preoperative biliary drainage on surgical outcome after pancreatoduodenectomy

BACKGROUND

The role of preoperative biliary drainage in patients with biliary obstruction undergoing pancreatoduodenectomy remains controversial. Several authors failed to show any effect of preoperative biliary drainage, whereas others even reported an increased morbidity following pancreatoduodenectomy.

METHODS

Retrospective analysis was performed in a consecutive series of 257 patients undergoing pancreatoduodenectomy between November 1993 and November 1999.

RESULTS

Ninety-nine patients (38%) underwent preoperative biliary drainage for a median time period of 10 days (range 1 to 41) prior to resection. Cumulative postoperative morbidity was 47% (120 patients), the reoperation rate was 4.3% (11 patients), and mortality was 2.3% (6 patients). There was no difference in total morbidity, infectious complications, reoperation rate, mortality, or long-term survival between patients with or without preoperative biliary drainage.

CONCLUSIONS

Preoperative biliary instrumentation and biliary drainage do not affect early or late outcome in patients undergoing pancreatoduodenectomy.

O, Ceneviva R. EVOLUÇÃO DA FIBROSE BILIAR SECUNDÁRIA EM RATOS TRATADOS MEDIANTE DERIVAÇÃO BÍLIO-DUODENAL OU BÍLIO-JEJUNAL COM ALÇA DE ROUX MEDINDO 5, 10 E 15 CM

A modalidade de derivação bílio-digestiva empregada no tratamento da colestase extra-hepática crônica pode influenciar na reparação das lesões hepáticas. Avaliou-se o desempenho das derivações bílio-duodenal e bílio-jejunal em Y de Roux com alça exclusa de diferentes comprimentos na reparação das lesões morfológicas e funcionais do fígado de ratos com fibrose biliar secundária. Foram utilizados ratos Wistar, com 15 dias de obstrução biliar, alocados em 5 grupos de 6 animais. O grupo OB caracterizou as alterações da fibrose biliar. Os animais remanescentes foram tratados mediante derivação com o duodeno (grupo DBD), e com o jejuno, em alça exclusa de 5cm (grupo DBJ5), 10cm (grupo DBJ10) e 15cm (grupo DBJ15), sendo reavaliados 3 meses depois. Outros 6 animais foram submetidos à intervenção simulada e considerados grupo controle (IS). Todos animais foram submetidos à avaliação morfométrica do fígado, análise bioquímica do sangue e microbiológica da bile, estudo da função mitocondrial hepática e verificação do peso úmido do fígado e do baço. Na análise estatística adotou-se o nível de significância de 5%. Houve aumento significativo do peso estimado, em g/Kg de peso corporal, dos ductos biliares, da fibrose e dos hepatócitos nos animais do grupo OB (medianas de 1,30; 10,03 e 37,0) em relação aos animais controles (IS) (medianas de 0,03; zero e 29,37). Após tratamento, ocorreu regressão significativa do peso estimado dos ductos biliares e da fibrose, com valores medianos de 0,22 e 0,22 para o grupo DBD, 0,45 e 3,31 para o grupo DBJ5 e 0,22 e 5,0 para o grupo DBJ15. Houve regressão significativa do peso estimado dos hepatócitos apenas nos grupos derivados com o jejuno, com valores medianos de 31,93; 24,46 e 28,52. Ocorreu aumento significativo do peso úmido do fígado e do baço no grupo OB (medianas em g/Kg de peso corporal de 49,85 e 5,71) em relação ao grupo IS (30,0 e 3,04). Houve regressão significativa do peso do fígado em todos os tratamentos e do peso do baço nos animais tratados com derivação bílio-jejunal, (valores medianos de 35,59 e 2,53 para DBJ5, 37,54 e 2,82 para DBJ10 e 32,73 e 2,93 para DBJ15). Após o tratamento, surgiram infiltrado inflamatório misto, nos espaços portais, refluxo enterobiliar e contaminação bacteriana da bile. Houve aumento significativo no consumo de oxigênio pela mitocôndrias hepáticas nos estados 3 e 4 no grupo OB (medianas de 101,55 e 31,05 nanoátomos de O2/mgprot./min), em relação ao grupo IS (medianas de 57,22 e 15,51). Após o tratamento, normalizou-se o consumo energético apenas nos animais do grupo DBJ15 (medianas de 52,38 e 14,8). O desempenho da derivação bíilio-jejunal indica a importância de avaliar alternativas que possam minimizar o contato do conteúdo entérico com a via biliar.

The increment of purine specific sodium nucleoside cotransporter mRNA in experimental fibrotic liver induced by bile duct ligation and scission

We investigated the expression profiles of rat fibrotic liver induced by bile duct ligation and scission (BDL/S) using the 3'-directed cDNA libraries. The possibility that the 3'directed cDNA library represents the mRNA population faithfully was examined by northern blots. During the northern analysis based on fibrotic liver expression profile, we found for the first time that purine specific sodium nucleoside cotransporter (SPNT) was upregulated in BDL/S-induced fibrotic liver. To determine whether the accumulation of bile juice could affect the expression of SPNT mRNA or not, we examined the change of SPNT mRNA expression at 3, 14, 28 days after BDL/S operation. No change in SPNT expression was observed in rat liver at 3 days after surgery. In contrast, there were significant increases in SPNT expression at 14 and 28 days after surgery. We also examined whether chronic liver damage affected SPNT mRNA expression. SPNT mRNA level was significantly increased in BDL/S-induced fibrotic rat liver, whereas no significant change was obserbed in fibrotic livers chronically exposed to carbon tetrachloride or dimethylnitrosamine. From the above results, although further study might be needed, it was considered that the increment of SPNT mRNA in BDL/S liver morphological compatibility to human was remarkable.

Regression of human cirrhosis. Morphologic features and the genesis of incomplete septal cirrhosis

CONTEXT

Cirrhosis is widely regarded as being irreversible. Recent studies have demonstrated that fibrosis may decrease with time in humans and experimental animals if the disease activity becomes quiescent. The histologic appearance of regressing cirrhosis in the human has not been described in detail.

OBJECTIVES

To define histologic parameters that indicate regression of cirrhosis and to provide an interpretation of how regression occurs from a histologic point of view.

DESIGN

A patient who underwent a series of biopsies that showed apparent regression of hepatitis B cirrhosis is presented. In addition, 52 livers removed at transplantation having cirrhosis or incomplete septal cirrhosis were graded for histologic parameters that suggest progression or regression of fibrosis. Progression parameters were steatohepatitis, inflammation, bridging necrosis, and piecemeal necrosis. The regression parameters (collectively called the hepatic repair complex) were delicate perforated septa, isolated thick collagen fibers, delicate periportal fibrous spikes, portal tract remnants, hepatic vein remnants with prolapsed hepatocytes, hepatocytes within portal tracts or splitting septa, minute regenerative nodules, and aberrant parenchymal veins.

RESULTS AND CONCLUSIONS

Regression parameters were found in all livers and were prominent in the majority. Livers with micronodular cirrhosis, macronodular cirrhosis, and incomplete septal cirrhosis demonstrate a histologic continuum. A continuum of regressive changes was also seen within individual livers. These appearances allow one to understand visually how fibrous regions of hepatic parenchyma can be returned toward a normal appearance. Many examples of incomplete septal cirrhosis could be the product of regressed cirrhosis.

Epidermal growth factor is decreased in liver of rats with biliary cirrhosis but does not act as paracrine growth factor immediately after hepatectomy

BACKGROUND/AIMS

Epidermal growth factor, a potent mitogen for hepatocytes and cholangiocytes, is thought to act as an immediate-early gene after partial hepatectomy. Since regeneration is impaired in cirrhosis, we explored the expression of epidermal growth factor in cirrhotic rat liver immediately after partial hepatectomy.

METHODS

Cirrhosis was induced by bile duct ligation (n=21); sham-operated animals served as controls (n=21). Twenty-five days after initial surgery animals were subjected to 70% partial hepatectomy or sham operation; the liver was sampled before surgery and 20, 40 and 90 min thereafter. Epidermal growth factor mRNA levels were assessed by quantitative reverse transcription polymerase chain reaction. Protein expression was estimated by immunohistochemistry using a polyclonal antibody against epidermal growth factor.

RESULTS

Before hepatectomy, epidermal growth factor mRNA averaged 70.3+/-39.9 pg/microg of total RNA in controls; this was markedly decreased to 21.9+/-12.7 pg/microg RNA in bile duct ligation (p<0.01). Epidermal growth factor mRNA did not increase after partial hepatectomy in either group, with the exception of sham-operated controls. Immunohistochemistry revealed that partial hepatectomy had no effect on epidermal growth factor expression. Hepatocytes showed uniformly cytosolic epidermal growth factor in controls, while in bile duct ligation immunostaining was faint or absent. Cholangiocytes exhibited a strong cytosolic staining in all experimental groups.

CONCLUSIONS

The present study shows that epidermal growth factor is reduced in the cirrhotic liver. This could contribute to the loss of parenchymal liver tissue observed in cirrhosis. The lack of up-regulation after PH sheds doubt on the role of epidermal growth factor as an immediate-early gene in hepatic regeneration. Further, we demonstrate that epidermal growth factor accumulates in cholangiocytes. This observation is strong evidence for involvement of the mitogen epidermal growth factor in the proliferation of bile ducts during cirrhogenesis.