Secondary bile acids and the biliary epithelia: The good and the bad

The biliary tract has been considered for several decades a passive system just leading the hepatic bile to the intestine. Nowadays several researches demonstrated an important role of biliary epithelia (i.e. cholangiocytes) in bile formation. The study of biliary processes therefore maintains a continuous interest since the possible important implications regarding chronic cholestatic human diseases, such as primary biliary cholangitis or primary sclerosing cholangitis. Bile acids (BAs), produced by the liver, are the most represented organic molecules in bile. The physiologic importance of BAs was initially attributed to their behavior as natural detergents but several studies now demonstrate they are also important signaling molecules. In this minireview the effect of BAs on the biliary epithelia are reported focusing in particular on secondary (deriving by bacterial manipulation of primary molecules) ones. This class of BAs is demonstrated to have relevant biological effects, ranging from toxic to therapeutic ones. In this family ursodeoxycholic and lithocholic acid present the most interesting features. The molecular mechanisms linking ursodeoxycholic acid to its beneficial effects on the biliary tract are discussed in details as well as data on the processes leading to lithocholic damage. These findings suggest that expansion of research in the field of BAs/cholangiocytes interaction may increase our understanding of cholestatic diseases and should be helpful in designing more effective therapies for biliary disorders.

Moving forward in the treatment of cholangiocarcinoma

Despite being the second most frequent primary liver tumor in humans, early diagnosis and treatment of cholangiocarcinoma (CCA) are still unsatisfactory. In fact, survival after 5 years is expected in less than one fourth of patients diagnosed with this disease. Rare incidence, late appearance of symptoms and heterogeneous biology are all factors contributing to our limited knowledge of this cancer and determining its poor prognosis in the clinical setting. Several efforts have been made in the last decades in order to achieve an improved classification/understanding with regard to the diverse CCA forms. Location within the biliary tree has helped to distinguish between intrahepatic, perihilar and distal CCA types. Sequence analysis contributed to identifying several characteristic genetic aberrations in CCA that may also serve as possible targets for therapy. Novel findings are expected to significantly improve the management of this malignancy in the near future. In this changing scenario our review focuses on the current and future strategies for CCA treatment. Both systemic and surgical treatments are discussed in detail. The results of the main studies in this field are reported, together with the ongoing trials. The current findings suggest that an integrated multidisciplinary approach to this malignancy would be helpful to improve its outcome.

Chronic rejection after liver transplantation: Opening the Pandora’s box

Chronic rejection (CR) of liver allografts causes damage to intrahepatic vessels and bile ducts and may lead to graft failure after liver transplantation. Although its prevalence has declined steadily with the introduction of potent immunosuppressive therapy, CR still represents an important cause of graft injury, which might be irreversible, leading to graft loss requiring re-transplantation. To date, we still do not fully appreciate the mechanisms underlying this process. In addition to T cell-mediated CR, which was initially the only recognized type of CR, recently a new form of liver allograft CR, antibody-mediated CR, has been identified. This has indeed opened an era of thriving research and renewed interest in the field. Liver biopsy is needed for a definitive diagnosis of CR, but current research is aiming to identify new non-invasive tools for predicting patients at risk for CR after liver transplantation. Moreover, the minimization or withdrawal of immunosuppressive therapy might influence the establishment of subclinical CR-related injury, which should not be disregarded. Therapies for CR may only be effective in the “early” phases, and a tailored management of the immunosuppression regimen is essential for preventing irreversible liver damage. Herein, we provide an overview of the current knowledge and research on CR, focusing on early detection, identification of non-invasive biomarkers, immunosuppressive management, re-transplantation and future perspectives of CR.

Gastrointestinal endoscopy in cirrhotic patient: Issues on the table

Patients with liver cirrhosis are fragile and present specific clinical hallmarks. When undergoing to gastrointestinal (GI) endoscopy, these subjects require an individual pre evaluation, taking into account: Level of haemostasis impairment, the individual risk of infection, the impact of sedation on hepatic encephalopathy and other factors. The overall assessment of liver function, employing common scoring systems, should be also assessed in the preprocedural phase. Beside some common general problems, regarding GI endoscopy in cirrhotic subjects, also specific issues are present for some frequent indications or procedures. For instance, despite an increased incidence of adenomas in cirrhosis, colon cancer screening remains suboptimal in subjects with this disease. Several studies in fact demonstrated liver cirrhosis as a negative factor for an adequate colon cleansing before colonoscopy. On the other hand, also the routine assessment of gastroesophageal varices during upper GI endoscopy presents some concern, since important inter-observer variability or incomplete description of endoscopic findings has been reported in some studies. In this review we discussed in details the most relevant issues that may be considered while performing general GI endoscopic practice, in patient with cirrhosis. For most of these issues there are no guidelines or clear indications. Moreover until now, few studies focused on these aspects. We believe that targeting these issues with corrective measures may be helpful to develop a tailored endoscopic approach for cirrhosis, in the future.

Current Advances in Basic and Translational Research of Cholangiocarcinoma

Simple Summary

Cholangiocarcinoma (CCA) is highly malignant biliary tract cancer, which is characterized by limited treatment options and poor prognosis. Basic science studies to seek therapies for CCA are also limited due to lack of gold-standard experimental models and heterogeneity of CCA resulting in various genetic alterations and origins of tumor cells. Recent studies have developed new experimental models and techniques that may facilitate CCA studies leading to the development of novel treatments. This review summarizes the update in current basic studies of CCA.

Abstract

Cholangiocarcinoma (CCA) is a type of biliary tract cancer emerging from the biliary tree. CCA is the second most common primary liver cancer after hepatocellular carcinoma and is highly aggressive resulting in poor prognosis and patient survival. Treatment options for CCA patients are limited since early diagnosis is challenging, and the efficacy of chemotherapy or radiotherapy is also limited because CCA is a heterogeneous malignancy. Basic research is important for CCA to establish novel diagnostic testing and more effective therapies. Previous studies have introduced new techniques and methodologies for animal models, in vitro models, and biomarkers. Recent experimental strategies include patient-derived xenograft, syngeneic mouse models, and CCA organoids to mimic heterogeneous CCA characteristics of each patient or three-dimensional cellular architecture in vitro. Recent studies have identified various novel CCA biomarkers, especially non-coding RNAs that were associated with poor prognosis or metastases in CCA patients. This review summarizes current advances and limitations in basic and translational studies of CCA.

COVID-19 in normal, diseased and transplanted liver

Starting from December 2019 the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has extended in the entire world giving origin to a pandemic. Although the respiratory system is the main apparatus involved by the infection, several other organs may suffer coronavirus disease 2019 (COVID-19)-related injuries. The human tissues expressing angiotensin-converting enzyme 2 (ACE2) are all possible targets of viral damage. In fact myocarditis, meningo-encephalitis, acute kidney injury and other complications have been described with regard to SARS-CoV-2 infection. The liver has a central role in the body homeostasis contributing to detoxification, catabolism and also synthesis of important factor such as plasma proteins. ACE2 is significantly expressed just by cholangiocytes within the liver, however transaminases are increased in more than one third of COVID-19 patients, at hospital admission. The reasons for liver impairment in the course of this infection are not completely clear at present and multiple factors such as: Direct viral effect, release of cytokines, ischemic damage, use of hepatotoxic drugs, sepsis, and others, may contribute to damage. While COVID-19 seems to elicit just a transient alteration of liver function tests in subjects with normal hepatic function, of concern, more severe sequelae are frequently observed in patients with a reduced hepatic reserve. In this review we report data regarding SARS-CoV-2 infection in subjects with normal or diseased liver. In addition the risks of COVID-19 in immunosuppressed patients (either transplanted or suffering for autoimmune liver diseases) are also described.

Natremia and liver transplantation: The right amount of salt for a good recipe

An adequate balance between electrolytes and clear water is of paramount importance to maintaining physiologic homeostasis. Natremia imbalance and, in particular, hyponatremia is the most frequent electrolyte abnormality observed in hospitalized subjects, involving approximately one-fourth of them. Pathological changes occurring during liver cirrhosis predispose patients to an increased risk of sodium imbalance, and hypervolemic hyponatremia has been reported in nearly 50% of subjects with severe liver disease and ascites. Splanchnic vasodilatation, portal-systemic collaterals’ opening and increased excretion of vasoactive modulators are all factors impairing clear water handling during liver cirrhosis. Of concern, sodium imbalance has been consistently reported to be associated with increased risk of complications and reduced survival in liver disease patients. In the last decades clinical interest in sodium levels has been also extended in the field of liver transplantation. Evidence that [Na⁺] in blood is an independent risk factor for in-list mortality led to the incorporation of sodium value in prognostic scores employed for transplant priority, such as model for end-stage liver disease-Na and UKELD. On the other hand, severe hyponatremic cirrhotic patients are frequently delisted by transplant centers due to the elevated risk of mortality after grafting. In this review, we describe in detail the relationship between sodium imbalance and liver cirrhosis, focusing on its impact on peritransplant phases. The possible therapeutic approaches, in order to improve transplant outcome, are also discussed. 

Hepatitis B virus recurrence after liver transplantation: An old tale or a clear and present danger?

Hepatitis B virus (HBV) recurrence after liver transplantation (LT) has been described more than 50 years ago. Similarly, to other clinical conditions, in which impairment of host immune defense favors viral replication, early reports described in details recurrence and reactivation of HBV in liver transplant recipients. The evidence of a possible, severe, clinical evolution of HBV reappearance in a significant percentage of these patients, allowed to consider, for some years, HBV positivity a contraindication for LT. Moving from the old to the new millennium this picture has changed dramatically. Several studies contributed to establish efficient prophylactic protocols for HBV recurrence and with the advent of more potent anti-viral drugs an increased control of infection was achieved in transplanted patients as well as in the general immune-competent HBV population. Success obtained in the last decade led some authors to the conclusion that HBV is now to consider just as a “mere nuisance”. However, with regard to HBV and LT, outstanding issues are still on the table: (1) A standard HBV prophylaxis protocol after transplant has not yet been clearly defined; (2) The evidence of HBV resistant strains to the most potent antiviral agents is claiming for a new generation of drugs; and (3) The possibility of prophylaxis withdrawal in some patients has been demonstrated, but reliable methods for their selection are still lacking. The evolution of LT for HBV is examined in detail in this review together with the description of the strategies adopted to prevent HBV recurrence and their pros and cons.

Neuroendocrine Changes in Cholangiocarcinoma Growth

Cholangiocarcinoma (CCA) is a highly aggressive malignancy that emerges from the biliary tree. There are three major classes of CCA-intrahepatic, hilar (perihilar), or distal (extrahepatic)-according to the location of tumor development. Although CCA tumors are mainly derived from biliary epithelia (i.e., cholangiocytes), CCA can be originated from other cells, such as hepatic progenitor cells and hepatocytes. This heterogeneity of CCA may be responsible for poor survival rates of patients, limited effects of chemotherapy and radiotherapy, and the lack of treatment options and novel therapies. Previous studies have identified a number of neuroendocrine mediators, such as hormones, neuropeptides, and neurotransmitters, as well as corresponding receptors. The mediator/receptor signaling pathways play a vital role in cholangiocyte proliferation, as well as CCA progression and metastases. Agonists or antagonists for candidate pathways may lead to the development of novel therapies for CCA patients. However, effects of mediators may differ between healthy or cancerous cholangiocytes, or between different subtypes of receptors. This review summarizes current understandings of neuroendocrine mediators and their functional roles in CCA.

Serum Levels of Granulocyte-Macrophage-colony-stimulating Factor and Stem-cell Factor During Liver Regeneration after Partial Hepatectomy in Humans

BACKGROUND

Multiple biological functions have been recognized regarding Granulocyte Macrophage-Colony Stimulating Factor (GM-CSF) and Stem Cell Factor (SCF).

AIM

To evaluate the serum changes of GM-CSF and SCF in patients undergoing surgical resection for liver tumor, in the regenerative phase after surgery in order to identify the possible relationship with the patient, tumor or surgical variables.

METHODS

Thirty-two consecutive patients (50% male, median age 66), undergoing hepatic resection of liver neoplasm, were evaluated. The liver tumor was Hepatocellular Carcinoma (HCC) in 44% of cases. Other tumors were cholangiocarcinoma and metastasis. Serum levels of GM-CSF and SCF were assessed at baseline and 2 days, 7 days and 4 weeks after surgery. Personal and clinical patient data were also recorded. The statistical analysis was carried out using t-test for unpaired data or ANOVA (repeated measure) for continuous variables and Fisher test for discrete variables.

RESULTS

GM-CSF levels remained constant after surgery and were compared to baseline values. SCF levels, on the other hand, increased during the time, after surgery. The evaluation of SCF levels (fold increase) according to surgical, patient and tumor variables evidenced some differences. At day 7 and week 4, SCF levels were statistically increased: i) in patients undergoing a large resection in comparison with others (p<0.05); ii) in patients non-cirrhotic in comparison with cirrhotic ones (p=0.02) and finally; iii) in patients with non-HCC tumor in comparison with HCC ones (p=0.02).

CONCLUSION

During liver regeneration in humans, SCF serum levels are increased allowing to hypothesize a possible role of this chemokine during tissue growth and remodeling.

De novo malignancies after liver transplantation: The effect of immunosuppression-personal data and review of literature

BACKGROUND

Immunosuppression has undoubtedly raised the overall positive outcomes in the post-operative management of solid organ transplantation. However, long-term exposure to immunosuppression is associated with critical systemic morbidities. De novo malignancies following orthotopic liver transplants (OLTs) are a serious threat in pediatric and adult transplant individuals. Data from different experiences were reported and compared to assess the connection between immunosuppression and de novo malignancies in liver transplant patients.

AIM

To study the role of immunosuppression on the incidence of de novo malignancies in liver transplant recipients.

METHODS

A systematic literature examination about de novo malignancies and immunosuppression weaning in adult and pediatric OLT recipients was described in the present review. Worldwide data were collected from highly qualified institutions performing OLTs. Patient follow-up, immunosuppression discontinuation and incidence of de novo malignancies were reported. Likewise, the review assesses the differences in adult and pediatric recipients by describing the adopted immunosuppression regimens and the different type of diagnosed solid and blood malignancy.

RESULTS

Emerging evidence suggests that the liver is an immunologically privileged organ able to support immunosuppression discontinuation in carefully selected recipients. Malignancies are often detected in liver transplant patients undergoing daily immunosuppression regimens. Post-transplant lymphoproliferative diseases and skin tumors are the most detected de novo malignancies in the pediatric and adult OLT population, respectively. To date, immunosuppression withdrawal has been achieved in up to 40% and 60% of well-selected adult and pediatric recipients, respectively. In both populations, a clear benefit of immunosuppression weaning protocols on de novo malignancies is difficult to ascertain because data have not been specified in most of the clinical experiences.

CONCLUSION

The selected populations of tolerant pediatric and adult liver transplant recipients greatly benefit from immunosuppression weaning. There is still no strong clinical evidence on the usefulness of immunosuppression withdrawal in OLT recipients on malignancies. An interesting focus is represented by the complete reconstitution of the immunological pathways that could help in decreasing the incidence of de novo malignancies and may also help in treating liver transplant patients suffering from cancer.

Liver transplantation for hepatocellular carcinoma: Where do we stand?

Hepatocellular carcinoma represents an important cause of morbidity and mortality worldwide. It is the sixth most common cancer and the fourth leading cause of cancer death. Liver transplantation is a key tool for the treatment of this disease in human therefore hepatocellular carcinoma is increasing as primary indication for grafting. Although liver transplantation represents an outstanding therapy for hepatocellular carcinoma, due to organ shortage, the careful selection and management of patients who may have a major survival benefit after grafting remains a fundamental question. In fact, only some stages of the disease seem amenable of this therapeutic option, stimulating the debate on the appropriate criteria to select candidates. In this review we focused on current criteria to select patients with hepatocellular carcinoma for liver transplantation as well as on the strategies (bridging) to avoid disease progression and exclusion from grafting during the stay on wait list. The treatments used to bring patients within acceptable criteria (down-staging), when their tumor burden exceeds the standard criteria for transplant, are also reported. Finally, we examined tumor reappearance following liver transplantation. This occurrence is estimated to be approximately 8%-20% in different studies. The possible approaches to prevent this outcome after transplant are reported with the corresponding results.

Dual Role of Bile Acids on the Biliary Epithelium: Friend or Foe?

Bile acids are a family of amphipathic compounds predominantly known for their role in solubilizing and absorbing hydrophobic compounds (including liposoluble vitamins) in the intestine. Bile acids also are key signaling molecules and inflammatory agents that activate transcriptional factors and cell signaling pathways that regulate lipid, glucose, and energy metabolism in various human disorders, including chronic liver diseases. However, in the last decade increased awareness has been founded on the physiological and chemical heterogeneity of this category of compounds and their possible beneficial or injurious effects on the biliary tree. In this review, we provide an update on the current understanding of the molecular mechanism involving bile acid and biliary epithelium. The last achievements of the research in this field are summarized, focusing on the molecular aspects and the elements with relevance regarding human liver diseases.

Pitfalls in the reporting of upper endoscopy features in cirrhotic patients

BACKGROUND

Upper endoscopy is the main tool for the accurate assessment of the risk of bleeding in cirrhotic patients.

AIM

To evaluate the diagnostic accuracy of upper endoscopy, in cirrhotic subjects, during common clinical practice.

METHODS

120 endoscopic reports produced in different hospitals in our region were retrospectively and randomly selected. After a general evaluation, aimed at assessing the description of various endoscopic features, reports were evaluated by four expert endoscopists and four expert hepatologists. Experts were asked to fill in a questionnaire for each single endoscopic procedure, regarding the diagnostic accuracy of the report.

RESULTS

Endoscopic reports lacked descriptions of the size of esophageal varices and red signs in 14% and 29% of cases respectively. Presence (or absence) of gastric varices or portal hypertensive gastropathy were not reported in 62% and 34% of cases respectively. According to expert endoscopists 41% of the reports were incomplete, while, according to hepatologists, reports were incomplete and inadequate for clinical purposes in 36% of cases.

CONCLUSION

Our study clearly evidenced a significant lack of information in reports on upper endoscopy in cirrhotic patients, and supports the prompt adoption of corrective strategies.

Different expression of VEGF and EGFL7 in human hepatocellular carcinoma

BACKGROUND

Vascular endothelial growth factor (VEGF) is one of several angiogenic factors expressed in cirrhosis and during progression to malignancy, that seem to play a major role in hepatocellular carcinoma development. Lately, another angiogenic factor, epidermal growth factor-like domain multiple 7 (EGFL7), has attracted interest due to its possible relationship with hepatocellular carcinoma metastasis.

AIMS

To evaluate expression of VEGF and EGFL7 in human hepatocellular carcinoma, compared to corresponding cirrhotic surrounding tissue.

METHODS

Tumoural and cirrhotic tissue was harvested from 12 consecutive patients undergoing surgical resection. VEGF and EGFL7 were assessed by immunofluorescence and quantitative reverse transcriptase-polymerase chain reaction, compared with normal controls.

RESULTS

Both angiogenic factors were over-expressed in cirrhotic livers compared to normal controls. VEGF and EGFL7 expressions did not differ according to disease aetiology, nodule size or other clinical variables. While VEGF expression was constant, regardless of tumour differentiation stage and unchanged compared to surrounding cirrhotic tissue, EGFL7 expression increased in less differentiated hepatocellular carcinoma.

CONCLUSIONS

The preferential expression of EGFL7 in less differentiated hepatocellular carcinoma compared to VEGF, suggests a possible important role of this angiogenic factor in a later oncogenic and infiltrative/metastatic phase.

Short-Term, Low-Dose Use of Tolvaptan as a Bridge Therapy to Expedite Liver Transplant for Severe Hyponatremic, Cirrhotic Patients With High Model for End-Stage Liver Disease Scores

For patients on liver transplant waiting lists, hyponatremia is associated with increased mortality before transplant and complications during the early posttransplant period. Conventional therapies, such as fluid restriction or hypertonic saline infusion, are of limited value. We describe 2 patients with high Model for End-Stage Liver Disease scores (> 30) who were referred to our unit for expedited liver transplant. While on waiting lists, these patients developed severe hyponatremia (< 125 mEq/L) that was refractory to conventional therapies. Low-dose, short-term tolvaptan therapy (15 mg/d for 5 d) was then administered, as a bridge therapy to transplant, resulting in prompt restoration of serum sodium levels without any major clinical event. One patient died a few days later as no suitable grafts were available. The other received a liver transplant, and the outcome was uneventful. In conclusion, our report demonstrates that a short-term, low-dose tolvaptan-based strategy promptly resolves hyponatremia in patients who are on expedited waiting lists for liver transplant, allowing surgery with improved sodium levels and possibly limiting peritransplant complications.

Standard bowel cleansing is highly ineffective in cirrhotic patients undergoing screening colonoscopy

BACKGROUND

Few data are available on tolerability and quality of standard bowel cleansing for colonoscopy in patients with chronic disease.

AIM

We seek to evaluate the tolerability and results of lavage solution for colonoscopy in cirrhotic patients in comparison with controls.

METHODS

Fifty-three cirrhotic and fifty-two normal subjects undergoing colonoscopy were prospectively enrolled in the study. Data regarding tolerability of lavage solution were harvested at the pre-procedure visit. Data on level of bowel cleansing and other endoscopic variables were recorded after the procedure.

RESULTS

Rate of failure to complete the prescribed bowel preparation and incidence of side effects during its administration were similar between cirrhotic and normal subjects. Despite this, cirrhotic patients exhibited an insufficient level of bowel preparation with approximately half exhibiting bad colon cleansing level (49% versus 5% control, p<0.001).

CONCLUSION

Alternative bowel cleansing protocols are needed for cirrhotic subjects to better match their colonoscopic screening needs.

Relationship between GH/IGF-1 axis, graft recovery, and early survival in patients undergoing liver transplantation. Biomed Res Int. 2014;2014:240873. [PMID: 24804205 PMCID: PMC3988744 DOI: 10.1155/2014/240873]

Background. High levels of IGF-1 have been reported in patients with initial poor function of the graft after liver transplantation (LT). Correlation with other clinical variables or early survival has not been extensively investigated. Aim. To evaluate the GH/IGF-1 profile as a function of liver recovery and patients' early survival after LT. Methods. 30 transplanted patients (23 survivors and 7 nonsurvivors), were retrospectively enrolled in the study. GH and IGF-1 serum levels were assessed at baseline, graft reperfusion, and 1, 7, 15, 30 , 90, and 360 days after LT. Individual biochemical variables were also recorded. Results. After grafting, IGF-1 in blood linearly correlated with cholesterol (r = 0.6, P = 0.001). IGF-1 levels from day 15 after surgery were statistically higher in survivors as compared to nonsurvivors. ROC curves analysis identified an IGF-1 cut-off >90 μg/L, from day 15 after surgery, as a good predictor of survival (sensitivity 86%, specificity 95%, and P < 0.001). Conclusions. After LT, GH levels correlate with the extent of cytolysis, while IGF-1 is an indicator of liver synthetic function recovery. IGF-1 levels >90 μg/L (day 15–30) seem to be an indicator of short-term survival.

A survey on mortality from non-variceal upper gastrointestinal bleeding: Is the emergency referral system adequate?

BACKGROUND

Non-variceal upper gastrointestinal bleeding (NVUGIB) is an important cause of mortality and morbidity worldwide. Little information is available on the clinical management of non-variceal upper gastrointestinal bleeding in Italy in relation to the current organization of the Italian Emergency Health Services into Level-I and Level-II Emergency Departments (ED), the latter being more complex structures with greater resources.

METHODS

A retrospective survey on clinical, endoscopic, and survival data was conducted by the regional sections of the 3 main Italian gastroenterological societies, AIGO, SIED and SIGE, recording all consecutive episodes of non-variceal upper gastrointestinal bleeding referred to 7 centres (4 of which were Level-II Emergency Departments) in Rome, Italy, during a one-year period. A total of 624 consecutive patients (64% males, mean age 67.6 ± 16.2 years) were included. Thirty-day mortality was 4.6%. Main factors associated with survival at both univariate and multivariate analysis were the presence of full Rockall score <5 and the admission to a Level-II Emergency Departments (p<0.001). Level-I Emergency Departments admitted patients with a full Rockall score ≥ 5 (p=0.02) more frequently than patients with negative endoscopic findings (p<0.001).

CONCLUSIONS

Referral of non-variceal upper gastrointestinal bleeding patients to Emergency Departments with more resources (Level-II) is associated with reduced mortality. Yet, unfortunately, high-risk patients were more often admitted to Level-I Emergency Departments, which suggests the need for a better organization of the emergency referral system.

Leptin attenuates ischemia-reperfusion injury in the rat liver

Leptin is an adipocytokine that reduces ischemic damage in several organs including brain and heart. STAT3 activation is a key step for the attainment of leptin effects in various tissues. We evaluated the possible effect of leptin on liver viability and STAT3 activation, in a rat model of ischemia-reperfusion injury. Rat livers, flushed and stored with Belzer solution (4° C for 24 h), were warmly reperfused (3.5 ml/min/g liver for 1 h at 37° C with O(2) ) with Krebs-Ringer bicarbonate. Treatment group underwent an identical protocol with the adjunct of Leptin (10 ng/ml). Liver effluent was harvested to assess LDH and AST output. Liver tissue was used for pSTAT3 expression (western blot and immunostaining), optical microscopy, TUNEL, and Cell Death Detection assays. The pSTAT3 expression was enhanced by administration of leptin. In parallel, LDH and AST output were reduced (P = 0.04 and P = 0.02 for LDH and AST, respectively). Optical microscopy, TUNEL, and Cell Death Detection assay results demonstrated increased viability in livers treated with leptin in comparison with others (Optical microscopy P = 0.02; TUNEL P = 0.01; Cell death Detection assay P = 0.003). In conclusion, cold storage and reperfusion with leptin reduce liver ischemia-reperfusion injury. This effect is associated with an increased expression of pSTAT-3.

Prevention of hepatitis C recurrence after liver transplantation: An update

Hepatitis C related liver failure and hepatocarcinoma are the most common indications for liver transplantation in Western countries. Recurrent hepatitis C infection of the allograft is universal and immediate following liver transplantation, being associated with accelerated progression to cirrhosis, graft loss and death. Graft and patient survival is reduced in liver transplant recipients with recurrent Hepatitis C virus (HCV) infection compared to HCV-negative recipients. Many variables may impact on recurrent HCV liver disease. Overall, excess immunosuppression is believed to be a key factor; however, no immunosuppressive regimen has been identified to be more beneficial or less harmful. Donor age limitations, exclusion of moderately to severely steatotic livers and minimization of ischemic times could be a potential strategy to minimize the severity of HCV disease in transplanted subjects. After transplantation, antiviral therapy based on pegylated IFN alpha with or without ribavirin is associated with far less results than that reported for immunocompetent HCV-infected patients. New findings in the field of immunotherapy and genomic medicine applied to this context are promising.

Plasma/erythrocyte ribavirin x100 ratio as an indicator of sustained virological response in HCV genotype 1 patients with early virological response

BACKGROUND

On-treatment predictors during antiviral therapy of HCV are useful because they allow discontinuation of an unnecessary treatment in non-responders. Our aim was to evaluate the usefulness of plasma and erythrocyte ribavirin levels in predicting sustained virological response (SVR) in HCV genotype 1 patients undergoing antiviral treatment.

METHODS

A total of 40 HCV genotype 1 patients treated with pegylated interferon-alpha2a 180 microg weekly plus ribavirin 1,000 or 1,200 mg daily (according to body weight) were included in the study. Plasma and erythrocyte ribavirin levels were evaluated in all patients at week 12 by HPLC. At week 24, ribavirin levels were reassessed in those achieving early virological response (EVR).

RESULTS

A total of 27 patients achieved EVR, whereas 17 achieved SVR. There was no difference among EVR and non-EVR patients in terms of plasma and erythrocyte ribavirin concentrations at week 12. At week 24, EVR patients obtaining SVR exhibited higher mean +/-sd levels of ribavirin in plasma and lower levels in erythrocytes compared with non-SVR patients (in plasma 12.8 +/-10 versus 5.8 +/-4 microM [P<0.02] and in erythrocytes 1,053 +/-504 versus 1,613 +/-589 microM [P<0.03]). When the plasma ribavirin/erythrocyte ribavirin x100 ratio was compared, the difference was enhanced (1.5 +/-1.3 versus 0.4 +/-0.3 microM; P<0.01). Receiver operating characteristic curve analysis identified a cutoff for plasma ribavirin/erythrocyte ribavirin x100 ratio in predicting SVR of 0.71 with a negative predictive value of 0.8 and a positive predictive value of 0.9, whereas those related to EVR were 1 and 0.6, respectively.

CONCLUSIONS

Plasma ribavirin/erythrocyte ribavirin x100 ratio at week 24 seems to be a good indicator of SVR in HCV genotype 1 patients achieving EVR.

TUDCA prevents cholestasis and canalicular damage induced by ischemia-reperfusion injury in the rat, modulating PKCalpha-ezrin pathway

Cholestasis, induced by liver ischemia-reperfusion injury (IRI), is characterized by dilatation of bile canaliculi and loss of microvilli. Tauroursodeoxycholic acid (TUDCA) is an anti-cholestatic agent, modulating protein kinase C (PKC) alpha pathway. PKC reduces ischemic damage in several organs, its isoform alpha modulates ezrin, a key protein in the maintenance of cell lamellipoidal extensions. We evaluated the effects of TUDCA on cholestasis, canalicular changes and PKCalpha-ezrin expression in a rat model of liver IRI. Livers flushed and stored with Belzer solution or Belzer + 10 mm TUDCA (4 degrees C for 6 h) were reperfused (37 degrees C with O(2)) with Krebs-Ringer bicarbonate + 2.5 micromol/min of Taurocholate or TUDCA. Bile was harvested for bile flow assessment. Liver tissue was employed for Electron Microscopy (EM) and for PKCalpha and ezrin immunoblot and immunofluorescence. The same experiments were conducted with the PKCalpha inhibitor Go-6976. TUDCA-treated livers showed increased bile flow (0.25+/-0.17 vs. 0.042+/-0.02 microl/min/g liver, P<0.05) and better preservation of microvilli and bile canalicular area at EM. These effects were associated with increased PKCalpha and ezrin expression (P=0.03 and P=0.04 vs. control respectively), as also confirmed by immunofluorescence data. PKCalpha inhibition abolished these TUDCA effects. TUDCA administration during IRI reduces cholestasis and canalicular damage in the liver modulating PKCalpha-ezrin pathway.

Correlation between liver fibrosis and inflammation in patients transplanted for HCV liver disease

Hepatitis C virus (HCV) re-infection after liver transplantation (LT) is characterized by an accelerated disease progression in recent years with unclear mechanisms. We evaluate the relationship between progression of liver fibrosis and histological necro-inflammation in HCV recipients, according to age of transplant. Fifty-five patients transplanted (1993-2002) for HCV liver disease, were included in the study. Recipients were retrospectively stratified in three different age of transplant, of 40 months each: group 1) from January 1993 to May 1996; group 2) from June 1996 to august 1999; group 3) from September 1999 to December 2002. Grading (necro-inflammation) and staging (fibrosis) scores were evaluated in liver biopsies at 1, 2 and 3 years from LT (Ishak classification). For all age of transplant the main factor associated with fibrosis progression, was grading score (p < 0.05). However mean staging score for each point of grading increased from 0.3 +/- 0.2 in older LT to 0.7 +/- 0.5 in newer ones (p = 0.01). In conclusion in HCV-LT patients (1) liver fibrosis is strictly associated to histological necro-inflammation; (2) the proportion of this relationship has been changing in recent years since newer LT patients, show an increased amount of fibrosis in comparison with the older ones, for similar grading score.

Cyclosporine A versus tacrolimus monotherapy. Comparison on bile lipids in the first 3 months after liver transplant in humans

Biliary lipids output is reduced after liver transplantation and tends to normalize thereafter. Cyclosporine A (CyA) is reported to interfere with the normal bile-restoring process after liver grafting, but data are inconclusive, in particular regarding the comparison with the other widely used calcineurin inhibitor tacrolimus (TCR). Furthermore, previous researches were conducted in patients taking multiple immunosuppressive therapies and with a short follow up. In this study we readdressed this issue by comparing biliary lipids in the first 3 months after liver transplant, in 20 patients randomized to receive immunosuppression with CyA or TCR monotherapy. Bile samples, harvested through a T-tube at days 1, 3, 7, 15, 30, 60 and 90 were assessed for cholesterol, phospholipids, and total and individual concentrations of bile acids (BA). Liver and kidney function tests were evaluated as well. We found no differences between CyA and TCR in biochemical findings or in total biliary BAs, cholesterol, and phospholipids. However, CyA-treated patients showed lower levels of glycochenodeoxycholic acid at day 15, compared to those treated with TCR (P < 0.04). This difference normalized thereafter, without any biochemical or clinical effect at 3-month follow up.