Systematic review of response criteria and endpoints in autoimmune hepatitis by the International Autoimmune Hepatitis Group

BACKGROUND & AIMS

Autoimmune hepatitis (AIH) has been well characterised and codified through the development of diagnostic criteria. These criteria have been adapted and simplified and are widely used in clinical practice. However, there is a need to update and precisely define the criteria for both treatment response and treatment.

METHODS

A systematic review was performed and a modified Delphi consensus process was used to identify and redefine the response criteria in autoimmune hepatitis.

RESULTS

The consensus process initiated by the International Autoimmune Hepatitis Group proposes that the term 'complete biochemical response' defined as 'normalization of serum transaminases and IgG below the upper limit of normal' be adopted to include a time point at 6 months after initiation of treatment. An insufficient response by 6 months was a failure to meet the above definition. Non-response was defined as '<50% decrease of serum transaminases within 4 weeks after initiation of treatment'. Remission is defined as liver histology with a Hepatitis Activity Index <4/18. Intolerance to treatment was agreed to stand for 'any adverse event possibly related to treatment leading to potential drug discontinuation'.

CONCLUSIONS

These definitions provide a simple and reproducible framework to define treatment response and non-response, irrespective of the therapeutic intervention. A consensus on endpoints is urgently required to set a global standard for the reporting of study results and to enable inter-study comparisons. Future prospective database studies are needed to validate these endpoints.

LAY SUMMARY

Consensus among international experts on response criteria and endpoints in autoimmune hepatitis is lacking. A consensus on endpoints is urgently required to set a global standard for the reporting of study results and to enable the comparison of results between clinical trials. Therefore, the International Autoimmune Hepatitis Group (IAIHG) herein presents a statement on 5 agreed response criteria and endpoints: complete biochemical response, insufficient response, non-response, remission, and intolerance to treatment, which can be used to guide future reporting.

5-aminosalicylic acid inhibits the expression of oncomiRs and pro-inflammatory microRNAs: an in vitro study

5-aminosalicylic acid (5-ASA) is commonly used as the first-line treatment for ulcerative colitis (UC). In this study, we show that the mechanism responsible for the protective effect of 5-ASA is associated with the modulation of non-coding microRNA molecule (miRNA) expression. Stimulation of human intestinal epithelial cells (Caco-2) with 1000 μM of 5-ASA suppressed the levels of miR-125b, miR-150, miR-155, miR-346 and miR-506, which are known to be involved in the regulation of colitis and/or colorectal cancer in patients with inflammatory bowel disease. The 5-ASA-induced inhibitions of these miRNAs were associated with significant inductions of their target genes such as vitamin D receptor (VDR), suppressor of cytokine signaling (SOCS1), Forkhead box O (FOXO3a) and DNA methyltransferase 1 (DNMT1). The relationships between the selected miRNAs and their target genes were further confirmed in Caco-2 cells transfected of with specific miRNA inhibitors or miRNA mimics. Moreover, we showed that 5-ASA has the potential to hinder miR-155 expression induced by the transfection of miR-155 mimic into Caco-2 cells. These findings underline the anti-inflammatory and chemoprotective effects of 5-ASA treatment.

S-adenosyl-L-methionine (SAMe) halts the autoimmune response in patients with primary biliary cholangitis (PBC) via antioxidant and S-glutathionylation processes in cholangiocytes

S-adenosyl-L-methionine is an endogenous molecule with hepato-protective properties linked to redox regulation and methylation. Here, the potential therapeutic value of SAMe was tested in 17 patients with PBC, a cholestatic disease with autoimmune phenomena targeting small bile ducts. Nine patients responded to SAMe (SAMe responders) with increased serum protein S-glutathionylation. That posttranslational protein modification was associated with reduction of serum anti-mitochondrial autoantibodies (AMA-M2) titers and improvement of liver biochemistry. Clinically, SAMe responders were younger at diagnosis, had longer duration of the disease and lower level of serum S-glutathionylated proteins at entry. SAMe treatment was associated with negative correlation between protein S-glutathionylation and TNFα. Furthermore, AMA-M2 titers correlated positively with INFγ and FGF-19 while negatively with TGFβ. Additionally, cirrhotic PBC livers showed reduced levels of glutathionylated proteins, glutaredoxine-1 (Grx-1) and GSH synthase (GS). The effect of SAMe was also analyzed in vitro. In human cholangiocytes overexpressing miR-506, which induces PBC-like features, SAMe increased total protein S-glutathionylation and the level of γ-glutamylcysteine ligase (GCLC), whereas reduced Grx-1 level. Moreover, SAMe protected primary human cholangiocytes against mitochondrial oxidative stress induced by tBHQ (tert-Butylhydroquinone) via raising the level of Nrf2 and HO-1. Finally, SAMe reduced apoptosis (cleaved-caspase3) and PDC-E2 (antigen responsible of the AMA-M2) induced experimentally by glycochenodeoxycholic acid (GCDC). These data suggest that SAMe may inhibit autoimmune events in patients with PBC via its antioxidant and S-glutathionylation properties. These findings provide new insights into the molecular events promoting progression of PBC and suggest potential therapeutic application of SAMe in PBC.

Evaluation of Liver Graft Recipient Workup in Predicting of Early Cardiovascular Events During Liver Transplantation: A Single-Center Experience

BACKGROUND

Cardiovascular events (CVE) contribute to serious complications and death after liver transplantation (LT). Troponin I (TnI) level >0.07 mg/L and prior cardiac disease are known to be the independent predictors for posttransplant CVE. We evaluated single-center cardiac workup to predict early cardiovascular morbidity and mortality after LT.

PATIENTS AND METHODS

We recruited 105 consecutive liver transplant recipients (male/female, 59/46; mean age, 51.66 ± 11.67 years). The cardiological assessment at evaluation for LT included medical history, electrocardiogram, echocardiography, Holter monitoring, and exercise test. We collected data regarding CVE including hypotonia with catecholamine usage, arrhythmia, sudden cardiac death, pulmonary edema, and myocardial infarction within 7 days after LT.

RESULTS

CVE during LT occurred in 42 recipients (40%) and after LT in 9 patients (8.57%). Proposed cutoff level of TnI >0.07 mg/L did not correlate with CVE during operation (P = .73) or after LT (P = .47). CVE during LT was associated with arterial hypertension in medical history (P <.001), right ventricular systolic pressure (P< .05), and clinical scores: Child-Pugh (P = .04), Model for End-Stage Liver Disease (MELD) (P = .04), MELD incorporating serum sodium (P<.03), and integrated MELD score (P = .01). CVE after LT correlated only with arrhythmia (P<.001) and catecholamine usage (P < .05) perioperatively. Of interest, catecholamine usage during LT was associated with prolonged stay at the intensive care unit (P < .05).

CONCLUSION

The single-center algorithm with noninvasive cardiac procedures without TnI assessment is optimal in evaluation before LT; however, medical history and severity of the liver disease are crucial for short-term cardiovascular morbidity after LT.

Patient Quality of Life After Liver Transplantation in Terms of Emotional Problems and the Impact of Sociodemographic Factors

INTRODUCTION

Liver transplantation is recognized as an effective and necessary treatment of chronic as well as acute hepatic failure. The assessment of quality of life (QoL) after transplantation represents an ancillary tool to evaluate the efficacy of solid organ transplantation in addition to graft and patient survival rates and complications. The global assessment of QoL after transplantation usually confirms improvement compared to pretransplant conditions.

PURPOSE

An attempt to evaluate the quality of life of patients after liver transplantation, with particular reference to sociodemographic factors and emotional problems.

MATERIALS AND METHODS

The study group included 121 patients (55 women and 66 men) at the age of 19 to 71 years who underwent surgery in the Central Teaching Hospital of the Medical University of Warsaw and the Infant Jesus Teaching Hospital in Warsaw, and were subsequently treated in an outpatient transplant clinic. The scoring procedure for the areas analyzed was based on the 36-Item Short Form Health Survey (SF-36) and the Hospital Anxiety and Depression Scale (HADS).

RESULTS

Higher patients age was correlated with lower quality of life of patients after liver transplantation, including physical functioning (patients >40 years of age declared lower physical performance, and patients <30 years of age indicated greatest limitations in their kind of work or other activities). The frequency of pain was also age-dependent (mostly patients >50 years of age). Women more often than men had worrying thoughts, were feeling tense or wound up, and had sudden feelings of anxiety or panic. By contrast, older people often declared that they felt to be slowed down.

CONCLUSIONS

To reduce pain and to improve physical performance of the study patients, rehabilitation procedures should be considered. Patients indicating symptoms associated with anxiety and depression should be referred to a clinical psychologist.

Expert clinical management of autoimmune hepatitis in the real world

BACKGROUND

High-quality data on the management of autoimmune hepatitis (AIH) are scarce. Despite published guidelines, management of AIH is still expert based rather than evidence based.

AIM

To survey expert hepatologists, asking each to describe their practices in the management of patients with AIH.

METHODS

A survey questionnaire was distributed to members of the International AIH Group. The questionnaire consisted of four clinical scenarios on different presentations of AIH.

RESULTS

Sixty surveys were sent, out of which 37 were returned. None reported budesonide as a first line induction agent for the acute presentation of AIH. Five (14%) participants reported using thiopurine S-methyltransferase measurements before commencement of thiopurine maintenance therapy. Thirteen (35%) routinely perform liver biopsy at 2 years of biochemical remission. If histological inflammatory activity is absent, four (11%) participants reduced azathioprine, whereas 10 (27%) attempted withdrawal altogether. Regarding the management of difficult-to-treat patients, mycophenolate mofetil is the most widely used second-line agent (n = ~450 in 28 centres), whereas tacrolimus (n = ~115 in 21 centres) and ciclosporin (n = ~112 in 18 centres) are less often reported. One centre reported considerable experience with infliximab, while rescue therapy with rituximab has been tried in seven centres.

CONCLUSIONS

There is a wide variation in the management of patients with autoimmune hepatitis even among the most expert in the field. Although good quality evidence is lacking, there is considerable experience with second-line therapies. Future prospective studies should address these issues, so that we move from an expert- to an evidence- and personalised-based care in autoimmune hepatitis.

The effect of short term treatment with probiotic VSL#3 on various clinical and biochemical parameters in patients with liver cirrhosis

The evidence is mounting that alterations of innate immunity and gut microbiota contribute to chronic liver disease and its complications. Modulation of intestinal microbiota is an emerging therapeutic strategy in hepatology. Probiotics through modulation of intestinal milieu have the potential to affect the course of liver disease. The data concerning the influence of probiotics on various plasma molecules and compounds involved in the pathogenesis of hyperdynamic circulatory state in liver cirrhosis is still not confluent and require further evaluation. In our study twenty patients with compensated and decompensated liver cirrhosis and ten healthy controls received probiotic VSL#3 daily for 28 days. Plasma levels of interleukin 6 (IL-6), vascular endothelial growth factor (VEGF), plasminogen activator inhibitor (PAI), macrophage inflammatory protein 3/α (MIP-3 α/CCL20), monocyte chemotactic protein-1α (MCP-1/CCL2), human myeloperoxidase (MPO), nitric oxide (NO), prostaglandins, thromboxane (TXB₂) and big-endothelin were measured at baseline, day 14 and 28 of probiotic administration. The incidence of hepatic encephalopathy was assessed with critical flicker frequency. Changes in clinical, biochemical and microbiological parameters were evaluated. The stage of liver cirrhosis correlated with an increase in plasma levels of pro-inflammatory cytokines (IL-6) and chemotactic chemokines involved in immune cell trafficking (MIP-3α/CCL20). Probiotic administration in patients with liver cirrhosis led to modulation of plasma levels of several molecules and compounds measured (MIP-3α/CCL20, NO, big-endothelin, TXB₂ and MPO). The grade of encephalopathy during the course of probiotic supplementation remained unaffected in both groups of patients. VSL#3 treatment was well tolerated and safe in patients with liver disease. In patients with compensated and decompensated liver cirrhosis, VSL#3 manipulates selected plasma molecules and compounds involved in hyperdynamic circulatory dysfunction. Short term VSL#3 administration affects several clinical and biochemical parameters commonly altered in liver cirrhosis.

Apolipoprotein E4 allele is associated with substantial changes in the plasma lipids and hyaluronic acid content in patients with nonalcoholic fatty liver disease

Fat may affect progression of liver damage in patients with non-alcoholic fatty liver disease (NAFLD). In this study we characterize the state of lipid metabolism in 22 patients with NAFLD and different Apo-E variants. Total concentration of plasma total fatty acids was quantified by gas chromatography, while their derivatives by liquid chromatography/tandem mass spectrometry (LC ESI MS/MS). The ratio of plasma saturated fatty acid to monounsaturated fatty acid increased, whereas the ratio of polyunsaturated fatty acids to saturated fatty acids was reduced in Apo-E4 carriers. Simultaneously, the levels of individual plasma linoleic, arachidonic, and alpha linolenic acids significantly increased in subjects with the Apo-E4 allele. The 15-lipoxygenase metabolite, 13-hydroxyoctadecadienoic acid, was significantly higher in Apo-E3 carriers (p<0.006). 5-oxo-6,8,11,14-eicosatetraenoic acid was significantly elevated in Apo-E4 carriers (p<0.009). A significant difference in hyaluronic acid concentration (p<0.0016) as well as predicted advanced fibrosis (using the BARD scoring system) was found in Apo-E4 carriers (p<0.01). We suggest that a distinct mechanism of fibrosis between Apo E alleles. In Apo-E4 carriers, an elevation in 5-oxo-6,8,11,14-eicosatetraenoic acid synthesis and fatty acid dysfunction may induce fibrosis, while an inflammatory process may be the main cause of fibrosis in Apo-E3 carriers.

Assessment of a modified Child-Pugh-Turcotte score to predict early mortality after liver transplantation

OBJECTIVE

The Model for End-Stage Liver Disease (MELD) predicts mortality on the transplant list; however, it has not been of much use to predict posttransplant outcomes. Several prognostic models have been tested among patients with cirrhosis; nevertheless, their predictive value has not been established in the posttransplant setting. We recently modified the Child-Pugh-Turcotte (CPT) score by adding creatinine levels (CPT + Cr), which has proven useful for patients with alcoholic cirrhosis. This retrospective analysis sought to predict early (1 month) mortality using CPT + Cr versus 5 other prognostic models in patients who underwent orthotopic liver transplantation (OLT) at our center.

MATERIALS AND METHODS

We included 48 consecutive patients (30 males, 18 females, median age 51 years). The predictive values of CPT + Cr were compared with CPT scores without or with the Huo modification, CPT + Na, MELD, and MESO, which is the MELD to serum Na ratio. Pearson correlations and ROC curves as evidenced by the area under the curve (AUC) were determined for each index. P < .05 was considered to be significant.

RESULTS

CPT + Cr showed the highest correlation with the risk of death (r = .368, P = .01); MELD and MESO were the lowest (r = .204, P = NS; and r = .254, P = NS, respectively). ROC analysis showed the best predictive value of CPT and CPT-Crea with AUC of 0.758 (P = .010) and 0.748 (P = .011) respectively, as compared to 0.689 for MESO and 0.659 for MELD (both NS).

CONCLUSIONS

A modified CPT score with creatinine levels may be of value to predict early death after OLT. Its usefulness must be validated in a prospective study of a large patient cohort.

Modified Charlson Comorbidity Index in predicting early mortality after liver transplantation

BACKGROUND

The Charlson Comorbidity Index for orthotopic liver transplantation (CCI-OLT) is a modified clinical score recently proposed to be useful for the assessment of long-term survival after OLT. It includes 9 associated conditions selected upon a multivariate analysis of a large cohort of transplant recipients. Its role in predicting early mortality after OLT has not yet been investigated. We sought to CCI-OLT as a potential predictor of 1-month mortality after OLT.

MATERIALS/METHODS

One hundred ninety-seven OLT were performed in our center between March 2002 and February 2009. After exclusion of patients who underwent transplantation for fulminant hepatic failure or those who underwent regrafting, we included a group of 169 patients. Viral (39%) and alcohol-induced (23%) cirrhosis were the most common indications for OLT. The CCI-OLT index was assessed in all patients.

RESULTS

In total, 146 (86%) subjects survived and 23 (14%) died within 1 month after LT. Fifty-one (30%) patients suffered at least 1 comorbidity that was included in the CCI-OLT. Direct comparison between survivor versus nonsurvivor groups showed no significant difference in terms of the total frequency of comorbidities (30.1% vs 30.4%; P > .99) or the number or the type of comorbidity. The most commonly associated condition in both groups was diabetes mellitus.

CONCLUSION

Unlike the case of long-term survival, CCI-OLT did not seem to predict early (1-month) mortality after OLT.

Vascular complications following adult piggyback liver transplantation with end-to-side cavo-cavostomy: a single-center experience

BACKGROUND

Vascular complications remain a significant cause of morbidity, graft loss, and mortality following orthotopic liver transplantation (OLT). These problems predominantly include hepatic artery and portal vein thrombosis or stenosis. Venous outflow obstruction may be specifically related to the technique of piggyback OLT.

MATERIALS AND METHODS

Between February 2002 and February 2009, we performed 200 piggyback OLT in 190 recipients. A temporary portacaval shunt was created in 44 (22%) cases, whereas end-to-side cavo-cavostomy was routinely performed for graft implantation. Pre-existent partial portal or superior mesenteric vein thrombosis was present in 17 (12%) cirrhotics in whom we successfully performed eversion thrombectomy, which was followed by a typical end-to-end portal anastomosis. The donor hepatic artery was anastomosed to the recipient aorta via an iliac interposition graft in 31 (16%) patients.

RESULTS

The 14 (7%) vascular complications included hepatic artery thrombosis (n = 5), hepatic artery stenosis (n = 3), aortic/celiac trunk rupture (n = 2), portal vein stenosis (n = 2), and isolated left and middle hepatic venous outflow obstruction (n = 1). There was also 1 case of arterial steal syndrome via the splenic artery. No patient experienced portal or mesenteric vein thrombosis. Therapeutic modalities included re-OLT, arterial/aortic reconstruction and splenic artery ligation. Vascular complications resulted in death of 5 (36%) patients.

CONCLUSION

Our experience indicated that piggyback OLT with an end-to-side cavo-cavostomy showed a low risk of venous outflow obstruction. Partial portal or mesenteric vein thrombosis is no longer an obstacle to OLT; it can be successfully managed with the eversion thrombectomy technique.

Ligation of oesophageal varices may increase formation of "deep" gastric collaterals

BACKGROUND/AIMS

Endosonography (EUS) is rarely used in the routine diagnostic of portal hypertension in patients with cirrhosis even though it has significantly higher sensitivity for detection of varices than gastroduodenoscopy. The aim of this cross-sectional study was to assess the features of portal hypertension identified with EUS and to analyze the effect of variceal ligation on the prevalence of "deep" varices in subjects with cirrhosis.

METHODOLOGY

A cohort of 121 patients was divided into 2 groups depending on whether they had a history of variceal bleeding treated with ligation or not.

RESULTS

"Deep" oesophageal varices and large (> 5 mm) gastric varices occurred significantly more common in patients with previous banding. Also, large "deep" gastric varices occurred significantly more common in the banded group with no or small varices than in the not-banded group with similar endoscopy. Sixty percent of banded patients who had grade II/III oesophageal varices on endoscopy had large "deep" gastric varices comparing to 20% of not-banded with the same endoscopical findings (p = 0.04).

CONCLUSION

Previous banding may increase the risk of the development of large "deep" oesophageal and gastric varices. Thus potential new indication for EUS in patients with cirrhosis could be a follow-up examination after successful eradication of varices.

Is prevalence of PBC underestimated in patients with systemic sclerosis?

BACKGROUND

Clinically significant primary biliary cirrhosis occurs in 2.5% of patients with systemic sclerosis. Primary biliary cirrhosis-specific autoantibodies include anti-mitochondrial, anti-glycoprotein 210, and anti-sp100 antibodies. The majority of asymptomatic anti-mitochondrial-positive subjects express histological features of primary biliary cirrhosis. Early detection of primary biliary cirrhosis is important, as timely introduction of ursodeoxycholic acid may improve prognosis. The aim was to assess the prevalence of MIT3 IgG-anti-mitochondrial, gp210, sp100 and other autoantibodies in patients with systemic sclerosis and compare the clinical and biochemical parameters in those who are primary biliary cirrhosis-specific autoantibodies positive and negative.

MATERIALS/METHODS

Fifty-two consecutive patients with systemic sclerosis were included. Thirty-three suffered from limited skin SS and 19 from diffuse SS.

RESULTS

Eight (15%) patients with systemic sclerosis tested positive for primary biliary cirrhosis-specific autoantibodies. No significant differences were observed between primary biliary cirrhosis-specific autoantibodies positive and negative subjects in terms of various demographic, clinical or biochemical features. A trend towards increased prevalence of chronic fatigue in primary biliary cirrhosis-specific autoantibodies positive patients was observed.

CONCLUSIONS

Primary biliary cirrhosis-specific autoantibodies were detected in 15% of the systemic sclerosis patients. Since patients with primary biliary cirrhosis-specific antibodies are at high-risk or do suffer from primary biliary cirrhosis, screening for primary biliary cirrhosis-specific autoantibodies may be considered during routine assessment of systemic sclerosis.

The PTPN22 1858T variant is not associated with primary biliary cirrhosis

The minor allele of a single nucleotide polymorphism (SNP) in the PTPN22 gene (1858T) encoding the Lyp-tyrosine phosphatase has been recently associated with multiple autoimmune disorders, raising the possibility that this variant may also represent a risk allele for primary biliary cirrhosis (PBC). We therefore investigated the possible association of the PTPN22(1858T) variant with PBC in a Canadian population. We studied 160 Caucasian patients with biopsy and antimitochondrial antibodies (AMA)-proven PBC who were genotyped for the PTPN22(C1858T) SNP using a single-base primer extension assay and mass spectrometry. The frequency of the PTPN22(1858T) allele was then compared between the patients and 290 healthy controls. No association was detected between the PTPN22(1858T) allele and PBC, the frequency of this variant being similar in patients with PBC (7.5%) and controls (8.4%). Restricting the analysis to patients with PBC with any second autoimmune condition or specifically with sicca syndrome or autoimmune thyroid disease also revealed no association with this variant. Thus the PTPN22(1858T) variant is not associated with PBC or with the combination of PBC and a second autoimmune disease. These data suggest that this variant does not confer risk for PBC and does not account for the frequent presence of other autoimmune diseases in patients with PBC.

Fatigue in chronic cholestasis

Fatigue is probably the most intriguing symptom affecting patients with chronic cholestatic disorders, in particular those with primary biliary cirrhosis. It is postulated that fatigue in patients with primary biliary cirrhosis may be associated with morphological abnormalities of the central nervous system secondary to accumulation of manganese. However, we are still far from understanding this complex issue.

Rapid correction of prothrombin time after low-dose recombinant factor VIIA in patients undergoing orthotopic liver transplantation

Orthotopic liver transplantation (OLTx) is associated with a major risk of blood loss resulting from portal hypertension, collateral circulation, and clotting disturbances. Application of a recombinant factor VIIa (rFVIIa) has been reported to promptly correct clotting abnormalities reducing the risk of intraoperative bleeding. This study included 8 patients who underwent OLTx for end-stage liver cirrhosis, with protrombin times (PT) exceeding the upper limit of normal by more than 4 seconds before surgery. All subjects were administered a small single intravenous dose of rFVIIa [mean 68.37 microg/kg body mass (range, 32.88-71.64)] 10 minutes prior to the skin incision. The PT was then measured 15 minutes later, following graft reperfusion, and 12 hours since drug application. All patients showed rapid correction of PT within 15 minutes after injection (median PT before injection 20.25 seconds vs 11.5 seconds after injection, P <.0001). Following the reperfusion PT was found to be prolonged again. These values are not significantly differ from those before surgery and are comparable to PT values after reperfusion in patients who did not receive rFVIIa. None of the patients developed thromboembolic complications. In conclusion, lower than recommended dose of rFVIIa caused rapid improvement in the PT shortly after injection. After reperfusion PT became prolonged again, which may account for the lack of thromboembolic complications observed in this group of patients.

Impaired localisation and transport function of canalicular Bsep in taurolithocholate induced cholestasis in the rat

BACKGROUND

Taurolithocholate induced cholestasis is a well established model of drug induced cholestasis with potential clinical relevance. This compound impairs bile salt secretion by an as yet unclear mechanism.

AIMS

To evaluate which step/s of the hepatocellular bile salt transport are impaired by taurolithocholate, focusing on changes in localisation of the canalicular bile salt transporter, Bsep, as a potential pathomechanism.

METHODS

The steps in bile salt hepatic transport were evaluated in rats in vivo by performing pharmacokinetic analysis of (14)C taurocholate plasma disappearance. Bsep transport activity was determined by assessing secretion of (14)C taurocholate and cholyl-lysylfluorescein in vivo and in isolated rat hepatocyte couplets (IRHC), respectively. Localisation of Bsep and F-actin were assessed both in vivo and in IRHC by specific fluorescent staining.

RESULTS

In vivo pharmacokinetic studies revealed that taurolithocholate (3 micro mol/100 g body weight) diminished by 58% canalicular excretion and increased by 96% plasma reflux of (14)C taurocholate. Analysis of confocal images showed that taurolithocholate induced internalisation of Bsep into a cytosolic vesicular compartment, without affecting F-actin cytoskeletal organisation. These effects were reproduced in IRHC exposed to taurolithocholate (2.5 micro M). Preadministration of dibutyryl-cAMP, which counteracts taurolithocholate induced impairment in bile salt secretory function in IRHC, restored Bsep localisation in this model. Furthermore, when preadministered in vivo, dibutyryl-cAMP accelerated recovery of both bile flow and bile salt output, and improved by 106% the cumulative output of (14)C taurocholate.

CONCLUSIONS

Taurolithocholate impairs bile salt secretion at the canalicular level. Bsep internalisation may be a causal factor which can be prevented by dibutyryl-cAMP.

Antidepressant induced cholestasis: hepatocellular redistribution of multidrug resistant protein (MRP2)

BACKGROUND

We report two cases of antidepressant induced cholestasis.

CASE REPORTS

We describe the first reported case of acute cholestasis due to citalopram (selective serotonin reuptake inhibitor) occurring in a patient who also experienced obstetric cholestasis in association with each of three pregnancies; in a second patient cholestasis developed due to dothiepin (tricyclic antidepressant), and six years later due to paroxetine. In both cases liver biopsies showed features of a "pure" cholestasis with total resolution within 1-6 months after withdrawal of the causative drug. Immunostaining for the canalicular transporter, multidrug resistant protein 2 (MRP2), responsible for biliary secretion of several organic anions including bilirubin glucuronides, showed sustained expression in both biopsies as well as relocalisation with appearance of strong staining of the basolateral membrane of the hepatocyte. This finding has also not been reported previously.

CONCLUSIONS

We postulate that intracellular redistribution of MRP2 may reflect an adaptive compensatory mechanism which helps in the elimination of the drug or its cholestatic metabolites from the hepatocyte back to the sinusoidal space and subsequent excretion in urine. Changes seen in these two patients differ from findings previously reported in rats where downregulation of mrp2 occurs in response to experimentally induced cholestasis. We speculate that the rat is more advanced than humans in its ability to downregulate canalicular transporter expression as protection against progressive intrahepatic cholestasis.

Hepatoprotection with tauroursodeoxycholate and beta muricholate against taurolithocholate induced cholestasis: involvement of signal transduction pathways

BACKGROUND

Tauroursodeoxycholate (TUDC) provides partial protection against taurolithocholate (TLC) induced cholestasis, possibly by inducing a signalling cascade activating protein kinase C (PKC). The potential protective effects of beta muricholic acid (beta-MC), another 7-beta-hydroxylated bile salt, have not previously been studied in TLC cholestasis.

AIMS

To study the effect of beta-MC on TLC induced cholestasis and also to investigate further the effects of agents affecting intracellular signalling, notably DBcAMP (a cell permeable cAMP analogue) and several protein kinase inhibitors.

METHODS

Functional studies were carried out analysing the proportion of hepatocyte couplets able to accumulate the fluorescent bile acid analogue cholyl-lysyl-fluorescein (CLF) into their sealed canalicular vacuole (cVA of CLF assay).

RESULTS

It was found that both beta-MC and DBcAMP were as effective as TUDC in protecting against TLC induced cholestasis. The PKC inhibitors staurosporin and H7 but not the specific protein kinase A (PKA) inhibitor KT5720 abolished the protective effects of TUDC and beta-MC. BAPTA/AM, a chelator of intracellular Ca(2+), significantly decreased the protective effect of both bile salts, and that of DBcAMP. PKC and PKA inhibitors had no effect on protection with DBcAMP.

CONCLUSIONS

Beta-MC was as effective as TUDC in protecting against TLC cholestasis. Mobilisation of Ca(2+) and activation of PKC, but not of PKA, are involved in the anticholestatic effect of the two 7-beta-hydroxylated bile salts. The hepatoprotective effects of DBcAMP involved Ca(2+) mobilisation, but not PKC or PKA activation.

[Autoimmune hepatitis: pathogenesis, clinical features and treatment]

Autoimmune hepatitis (AIH) is a chronic liver disease of unknown etiology. The incidence of AIH keeps rising, most probably because of increasing availability of the diagnostic tools permitting thorough differential diagnosis amongst liver diseases presenting histologically as chronic active hepatitis. In this review we focus on clinical aspects of autoimmune hepatitis and discuss pathogenesis, clinical features and treatment of AIH.

Effect of tauroursodeoxycholate and S-adenosyl-L-methionine on 17beta-estradiol glucuronide-induced cholestasis

BACKGROUND/AIMS

S-adenosyl-L-methionine (SAMe) and tauroursodeoxycholate (TUDC) exert an additive ameliorating effect on taurolithocholate (TLC)-induced cholestasis. The aims were to investigate the protective effect of SAMe on 17beta-estradiol-glucuronide (17betaEG) cholestasis and to find out whether SAMe and TUDC may exert an additive, ameliorating effect.

METHODS

Hepatocyte couplet function was assessed by canalicular vacuolar accumulation (cVA) of cholyllysylfluorescein (CLF). Cells were co-treated with 17betaEG and SAMe, TUDC, or both (protection study), or treated with 17betaEG and then with SAMe, TUDC or both (reversion study) before CLF uptake. Couplets were also co-treated with SAMe and dehydroepiandrosterone (DHEA), a competitive substrate for the sulfotransferase involved in 17betaEG detoxification. The effects of 17betaEG, SAMe and TUDC were also examined on intracellular distribution of F-actin.

RESULTS

Both SAMe and TUDC significantly protected against, and reversed, 17betaEG-induced cholestasis, but their effects were not additive. DHEA abolished the protective effect of SAMe. 17BetaEG did not affect the uptake of CLF into hepatocytes at the concentrations used, and also, it did not affect the intracellular distribution of F-actin.

CONCLUSIONS

17BetaEG does not affect the uptake of CLF into hepatocytes. SAMe and TUDC protect and reverse 17betaEG-induced cholestasis, but without an additive effect. Protection by SAMe may involve facilitating the sulfation of 17betaEG.

Visualization of the transport of primary and secondary bile acids across liver tissue in rats: in vivo study with fluorescent bile acids

BACKGROUND/AIMS

Lysyl fluorescein conjugated bile acid analogues (LFCBAA) closely parallel their natural counterparts. To assess LFCBAA as a tool for the visualization of bile acid transport within liver tissue.

METHODS

Wistar rats were administered physiological concentrations of the primary bile acid analogue cholyllysyl fluoroscein (CLF) and of the secondary bile acid analogue lithocholyllysyl fluorescein (LLF) and serial liver biopsies were taken at fixed intervals. Both compounds were also injected retrogradely into the biliary tree. Frozen sections were examined by fluorescence microscopy.

RESULTS

Both CLF and LLF were rapidly taken up from sinusoidal blood but differed significantly in their hepatic handling. CLF was rapidly transported into bile, whereas LLF transport was slower and produced significantly more bile duct fluorescence. LLF clearance showed a lobular gradient with last remaining bile acid being confined largely to zone 3. Both compounds were avidly taken up by cholangiocytes after injection intravenously or retrogradely into the biliary tree.

CONCLUSIONS

Visualization of LFCBAA by fluorescence microscopy may yield further information regarding hepatobiliary bile acid localization during studies of physiological and pathological mechanisms involved in transport of bile acids. The presence of both compounds within cholangiocytes strongly suggests that they may undergo a degree of chole-hepatic recirculation.

Control by signaling modulators of the sorting of canalicular transporters in rat hepatocyte couplets: role of the cytoskeleton

Hormonal control of the restoration of hepatocanalicular polarity in short-term cultured hepatocyte couplets was analyzed. One hour following isolation, couplets were unable to accumulate the fluorescent bile acid analogue, cholyl-lysyl-fluorescein (CLF), and showed a nonpolarized distribution of F-actin and mrp2 over the cell body. A progressive, time-dependent restoration of couplet-polarized function and morphology was reached after 4 hours of culture. Both dibutyryl cyclic adenosine monophosphate (DBcAMP) and the Ca(2+)-elevating compound, thapsigargin, accelerated restoration of normal couplet morphology and function. The DBcAMP-mediated stimulus was inhibited by the Ca(2+) chelator, 1, 2-bis-(o-aminophenoxy)-ethene-N,N,N',N'-tetra-acetate tetra-(acetomethyl)ester (BAPTA/AM), but not by the protein kinase A (PKA) inhibitors, KT5720 or H89, suggesting that Ca(2+) elevation rather than PKA activation is involved. N-(6-aminohexyl-5-chloro-1-napththalenesulfonamide (W-7), a calmodulin inhibitor, and the protein kinase C (PKC) activator, phorbol dibutyrate, inhibited both the basal and the DBcAMP-stimulated recovery of functional polarity, whereas staurosporine and Gö 6976, 2 PKC inhibitors, accelerated the basal recovery of polarized function. Disruption of the microtubule cytoskeleton by colchicine induced only minor changes under basal, but not under DBcAMP-stimulated, conditions. The Golgi complex disruptor, brefeldin A, significantly delayed, and the microfilament-disrupting agent, cytochalasin D, fully blocked, both processes. However, DBcAMP stimulated trafficking of vesicles containing CLF to the pericanalicular region under the last condition. Our results indicate that restoration of couplet polarity following isolation occurs via a Ca(2+)-calmodulin-mediated mechanism, which depends on microfilament, but not on microtubule integrity. A second pathway is activated by DBcAMP activation via Ca(2+)-calmodulin formation, whose requirements with respect to cytoskeletal components are opposite. PKC has a negative regulatory role in both pathways.

Increased incidence of chronic rejection in adult patients transplanted for autoimmune hepatitis: assessment of risk factors

BACKGROUND/AIM

It remains uncertain whether autoimmune hepatitis (AIH), as an original indication for orthotopic liver transplantation (OLTX), predisposes to the development of chronic rejection (CR) after surgery and published reports on heterogeneous groups of patients provided conflicting data. In this work we analyzed the incidence and risk factors for CR in a large cohort of adult patients transplanted for AIH in our unit.

RESULTS

A total of 1190 adult patients received OLTX in our center between 1982 and 1998. A total of 77 patients (6.5%) were transplanted for AIH and 12 (15.6%) patients from this group developed clinical and histological features of CR within a median time of 3.5 months after OLTX. Patients with AIH who developed CR were younger than other AIH patients at OLTX (32 vs. 44.2 ys; P=0.015) and more often had histological features of moderate or severe acute rejection (83 vs. 34%; P=0.002) on early post-OLTX biopsies. The incidence of CR in AIH patients was significantly higher than in subjects transplanted for other indications such as primary biliary cirrhosis (8.2%; P<0.05), primary sclerosing cholangitis (5.2%; P<0.05) or alcoholic cirrhosis (2.0%; P<0.001). Also, we observed a tendency to decreased incidence of CR with time in all transplanted subjects.

CONCLUSIONS

Apart from younger age at OLTX and higher incidence of severe acute rejection, patients with AIH who developed CR did not differ from other subjects transplanted for this indication. Unlike other studies, not stratified by diagnosis, recipient CMV negative status, young donor age, and HLA DR matching were not identified as risk factors for CR in AIH.

Plasma elimination of cholyl-lysyl-fluorescein (CLF): a pilot study in patients with liver cirrhosis

BACKGROUND

Cholyl-lysyl-fluorescein (CLF) is a fluorescein-labelled bile acid whose biological behaviour closely resembles that of naturally occurring cholyl glycine.

AIM

The aim of this study was to analyze the CLF plasma elimination in patients with liver cirrhosis.

METHODS

A dose of CLF at 0.02 mg/kg b.w. was administered i.v. in 26 patients with liver cirrhosis and 9 healthy volunteers. Blood samples were collected before injection and then at 10 min intervals over 60 min. Plasma fluorescence was measured by a luminescence spectrometer and residual fluorescence over the time of the study was compared in each group. Routine liver function tests (rLFTs) were performed before each injection.

RESULTS

Plasma elimination of CLF was significantly impaired in patients with cirrhosis compared to healthy subjects with p values <0.0001 at each analyzed time point. CLF test showed 100% sensitivity for liver cirrhosis when residual fluorescence was measured 30, 40, 50 and 60 min after injection. Routine LFTs showed 85% sensitivity for bilirubin, 84% for total bile acids, 69% for aspartate aminotransferase 62% for albumin and 50% for alkaline phosphatase. CLF elimination measured 60 min after injection correlated with Child-Pugh score (r=0.3945; p<0.05) and albumin (rs=0.6451; p<0.001). No adverse reaction or side effects of CLF were observed.

CONCLUSIONS

CLF test clearly distinguished between the two analyzed groups and was more sensitive than routine liver function tests. The test appears safe, simple to perform and analyze and after validation in larger cohorts of patients may have the potential to become a useful dynamic test of liver function.

Recurrent autoimmune LKM hepatitis with multiple relapses

We describe three females who since childhood and puberty have presented with several relapsing episodes of acute or chronic LKM positive hepatitis. Many episodes resolved spontaneously with recovery of normal liver function, although treatment with steroids, steroids/azathioprine was used at occasions. No clear pattern of precipitating factors has emerged though in some cases possible temporal relationship of episodes to menarche, oral contraceptives use or pregnancy has suggested a role for female sex hormones. We discuss briefly the possible mechanisms of LKM positive hepatitis, particularly in terms of drugs as possible trigger factors.

Wilson's disease with superimposed autoimmune features: report of two cases and review

We describe two females, 15 and 23 years old, respectively, who presented with classical features of Wilson's disease (WD) and several features of autoimmune hepatitis (AIH). The first patient was initially diagnosed as AIH and treated with prednisolone which caused clinical improvement, with an increase of serum albumin from 22 to 30 g/L, and a decrease of aspartate aminotransferase from 103 to 47 U/L. Subsequent diagnosis of WD and introduction of penicillamine gave excellent improvement and complete normalization of liver function tests. The second patient, at first also diagnosed as having AIH, was treated with steroids and azathioprine with initial improvement, but subsequent deterioration. The diagnosis of WD was made 2 years after initial diagnosis of AIH, as the patient reached end-stage liver disease and required a transplant. Therefore, d-penicillamine treatment was not attempted. We conclude that, in patients with AIH, a thorough screening for WD is necessary, particularly when the response to steroid therapy is poor. Conversely, in patients suffering from WD with superimposed features of AIH, a combination of steroids and penicillamine may be of benefit.

Different pathways of canalicular secretion of sulfated and non-sulfated fluorescent bile acids: a study in isolated hepatocyte couplets and TR- rats

BACKGROUND/AIMS

Fluorescent bile acids have proved useful for characterizing bile salt transport mechanisms. The aim of this study was to further validate the use of lysyl-fluorescein conjugated bile acid analogues as surrogate bile acids.

METHODS

We analyzed biliary excretion kinetics of cholyl lysyl fluorescein (CLF), lithocholyl lysyl fluorescein (LLF) and sulfo-lithocholyl lysyl fluorescein (sLLF), both in the isolated rat hepatocyte couplet model and in TR- rats with a selective canalicular transport defect of non-bile acid organic anions.

RESULTS

CLF and LLF, which like their natural nonsulfated bile acid congeners are expected to be handled by the canalicular bile salt export pump, were transferred into the bile canaliculus much faster than sLLF, a putative substrate for the canalicular multispecific organic anion transporter in both the in vivo and the in vitro models employed. The contention that different transport systems are involved in sulfated and non-sulfated lysyl fluorescein conjugated bile acids biliary excretion was supported further by studies using TR- rats, in which the cumulative biliary excretion of sLLF was reduced to 6% as compared with that of normal Wistar rats, in good agreement with values for its naturally-occurring radiolabeled parent compound sulfoglycolithocholate. In contrast, CLF and LLF were reduced to 66% and 52%, similar values to these for their congeners, [14C] glycocholate and [14C] lithocholate.

CONCLUSION

The close similarity in behavior of lysyl fluorescein conjugated bile acids to that of their naturally-occurring parent compounds in these different models gives support for both sulfated and nonsulfated lysyl fluorescein conjugated bile acids as substitute molecules for studies of bile acid transport.

Recurrence of autoimmune hepatitis after liver transplantation

BACKGROUND

The literature data on the recurrence of autoimmune hepatitis (AIH) after orthotopic liver transplantation (OLTX) is scanty.

METHODS

We analyzed the frequency of recurrent AIH in 47 patients who had been transplanted for AIH and survived at least 1 year after surgery. The following criteria were applied to diagnose recurrence: (1) positive autoantibodies in the titer> or =1:40; (2) hypertransaminasemia; (3) histological features of chronic hepatitis; (4) need of reintroduction or significant increase of steroids; and (5) lack of serum markers of viral hepatitis.

RESULTS

A total of 13 patients (1 male/12 females) developed recurrent AIH after an interval of 6-63 months after OLTX (mean 29 months). Mean AST level at recurrence was 542+/-129 U/L. Three patients from this group needed regrafting. Mismatch of DR3+ recipient and DR3- donor was not more common in the recurrent disease group (37%) compared to the nonrecurrence group (31%) (P=NS).

CONCLUSIONS

Recurrence of AIH after OLTX was diagnosed in a high proportion of patients and some of them required regrafting. DR3+ patients are not particularly prone to develop recurrence.

Autoimmune liver disease in patients with neoplastic diseases

BACKGROUND

Development of de novo autoimmune liver disease has not been well documented in patients with malignant diseases.

METHODS/RESULTS

In this paper we report on a series of six patients with neoplastic disorders who acquired liver disease with autoimmune features. Five patients had suffered from haematological neoplasms and one from colonic cancer. In two patients, liver disease was detected at the time of presentation with malignancy. In the remaining four, all of whom were successfully treated for malignancies, features of liver disease presented at intervals 24-72 months after the cancer diagnosis. Twelve liver specimens (11 biopsies and one hepatectomy specimen) were obtained at time intervals of 1-76 months after initial presentation of neoplastic disease. Biopsies from three patients showed features of hepatitis (one acute, one sub-acute, one chronic). Two patients had histological features suggestive of an overlap syndrome (one autoimmune hepatitis/primary biliary cirrhosis, one autoimmune hepatitis/primary sclerosing cholangitis). The sixth patient had features of autoimmune cholangiopathy. All but one responded well to steroid therapy with complete clinical and biochemical remission obtained 4 weeks to 8 months after steroid introduction. We discuss briefly possible aetiologies of autoimmune liver disease in these patients.

CONCLUSIONS

Autoimmune liver disease may be precipitated by therapy for neoplastic disease or malignant disease itself. The unusually heterogeneous clinicopathological findings in this group as well as the response to treatment support the concept of a wide spectrum of manifestations of autoimmune liver disease. The results may also suggest that autoimmune liver disease may be possibly added to the list of paraneoplastic syndromes. Further prospective studies are required to confirm a causal association and to determine whether the mechanisms involved are disease- or treatment-related.

Successful treatment of acquired perforating dermatosis with rifampicin in an Asian patient with sclerosing cholangitis

Acquired perforating dermatosis (APD) is a very rare disorder which has been described in association with systemic diseases such as diabetes mellitus, HIV infection or lymphoma. In this report we describe a patient with APD associated with sclerosing cholangitis and diabetes mellitus who was successfully treated with rifampicin. A 33-year-old Indian woman with a history of extensive pancreatic surgery, sclerosing cholangitis and insulin dependent diabetes mellitus was referred to our unit with intractable pruritus. She was treated with cholestyramine, ursodeoxycholic acid, several analgesics, UVB therapy, topical steroids, sedative antihistamines and plasmapheresis without significant improvement. Increasingly severe itching was associated with papular skin changes limited initially to the lower limbs but which later involved her entire body. Biopsy of a representative lesion showed the changes of APD. She was subsequently treated with rifampicin which produced a dramatic resolution of pruritus within 3 weeks and the skin changes progressively resolved over subsequent months. In this newly described association of APD with sclerosing cholangitis, rifampicin treatment appeared to be efficient in ameliorating pruritus and the papular skin changes typical of APD.

Tauroursodeoxycholate and S-adenosyl-L-methionine exert an additive ameliorating effect on taurolithocholate-induced cholestasis: a study in isolated rat hepatocyte couplets

The monohydroxy bile acid, taurolithocholate (TLC), causes cholestasis in vivo and in isolated perfused livers. It is also cholestatic in vitro and, in this study using isolated rat hepatocyte couplets, causes a reduction of the accumulation of (fluorescent) bile acid in the canalicular vacuoles (cVA) of this polarized cell preparation. The hepatoprotective bile acid, tauroursodeoxycholate (TUDCA), partially protects against the action of TLC when added at the same time. It also partially reverses the cholestatic effect if added after the cells have been exposed to TLC. A second hepatoprotective compound, S-adenosyl-L-methionine (SAMe) also not only partially protects against the action of TLC when added at the same time, but it too is able to partially reverse the cholestatic effect. Neither hepatoprotective agent is fully effective alone, but their effects are additive. In combination, a full restoration of cVA is observed in moderate cholestasis, but not in severe cholestasis. We discuss briefly some possible mechanisms involved in the additive mode of action of both hepatoprotective compounds. In summary, we show for the first time that SAMe and TUDCA can exert an additive effect in the amelioration of TLC-induced cholestasis in isolated rat hepatocyte couplets. This finding may be of possible clinical relevance.

Factors associated with progression of the disease before transplantation in patients with autoimmune hepatitis

AIMS/BACKGROUND

Studies on transplanted patients may provide clinically useful data on factors influencing progression of autoimmune hepatitis (AIH) since transplantation rather than death may now be considered as the most likely end-point of the disease. The aim of this work was to analyze risk factors related to progression of AIH before transplantation and provide guidelines for further prognostication with regards to the timing of transplantation.

METHODS

80 liver transplants in 68 patients with AIH were performed in our unit. The diagnosis was established on conventional clinical criteria. Parameters such as sex, age at diagnosis and transplantation or duration of the disease were evaluated in relation to: patient HLA DR status, disease presentation (aggressive or non-aggressive), presence of anti-LKM antibodies and concurrent immune disease.

RESULTS

AIH with concurrent immune disease occurred more commonly in females (90 vs. 61%; p = 0.0075) and was linked with markedly slower progression of the disease (125 vs. 66 mo; p = 0.002) as compared to subjects without such association. AIH without concurrent autoimmune disease occurred significantly more commonly in patients with DR3 phenotype (p = 0.01). Patients with positive anti-LKM autoantibodies were younger at transplantation (25.6 vs. 43.5 yr; p = 0.006) and had more rapid progression of their disease (14.3 vs. 103 mo; p = 0.001). Unlike previously reported series of non-transplanted patients, all anti-LKM positive subjects had no concurrent autoimmune disease.

CONCLUSIONS

Coincidence with another autoimmune disease is associated with a significantly longer disease history prior to transplantation and may possibly reflect greater responsiveness to immunosuppressive therapy before grafting. AIH without concurrent autoimmune disease, particularly if associated with DR4 negative phenotype, male sex and anti-LKM antibodies may characterize patients with rapid progression of the disease. None of these factors had a significant influence on 5 year survival after surgery.

Plasma clearance of cholyl-lysyl-fluorescein: a pilot study in humans

BACKGROUND/AIMS

Cholyl-lysyl-fluorescein is a fluorescent analogue of the natural bile acid, cholyl glycine. In vivo and in vitro studies showed that this analogue has many biological characteristics similar to cholyl glycine. In this study we analysed cholyl-lysyl-fluorescein plasma clearance in six healthy volunteers as a potential quantitative liver function test.

METHODS

The compound in water for injection was administered as an i.v. bolus in the dose of 0.02 mg/kg b.w.

RESULTS

The plasma elimination curve showed rapid, intermediate and slow phases of clearance. Half-life (T1/2 time) for the first (t1/2 1st phase), second (t1/2 2nd phase) and third (t1/2 3rd phase) phases of elimination was 1.7+/-0.9 min, 6.7+/-1.6 min and 68+/-17 min, respectively. Ninety-minute plasma retention (% dose/l plasma) was 2.2%. Cholyl-lysyl-fluorescein volume of distribution and residual fluorescence after 60 min were similar to the data obtained by others for natural or radiolabelled bile acids. In five out of six healthy volunteers a 25-fold higher dose of cholyl-lysyl-fluorescein (0.5 mg/kg b.w.) was injected to estimate the safety margins of the compound. This dose was eliminated at a disappearance rate similar to that of the dose of 0.02 mg/kg b.w. and did not cause any adverse reactions. Serum liver tests measured before and after injection did not change significantly.

CONCLUSIONS

This study showed that cholyl-lysyl-fluorescein clearance is similar to the clearance of endogenous natural bile acids and may potentially offer a new, dynamic test of liver function.

Synthesis, physical and biological properties of lithocholyl-lysyl-fluorescein: a fluorescent monohydroxy bile salt analogue with cholestatic properties

We have synthesised and characterised a fluorescent monohydroxy bile salt analogue, lithocholyl-lysyl-fluorescein and compared its physical and biological properties with those of lithocholate, glycolithocholate, sulpholithocholate, lithocholic acid glucuronide and taurocholate. The synthetic method used excess N-epsilon-CBZ-L-lysine methyl ester hydrochloride and lithocholic acid via N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinolone (EEDQ) to give lithocholyl-lysine. Lithocholyl-lysyl-fluorescein (LLF) was then prepared using equimolar amounts of lithocholyl-lysine and fluorescein isothiocyanate (FITC) in bicarbonate buffer. LLF retained an apple green fluorescence, similar to that of fluorescein. Unlike lithocholate, the critical micellar concentrations (CMCs) of LLF, glycolithocholate (GLC), lithocholic acid glucuronide (LG) and sulpholithocholic acid (SLC) were similar. HPLC retention times (tRs) of LLF and GLC were similar with a ratio of LLF/GLC of 1.05. In contrast, the tR of SLC (6.52 min) but not of LG (21.2 min) was more comparable to that of taurocholate (5.73 min). In rats under pentobarbital anaesthesia, the plasma half-life (t(1/2alpha)) (min) was 4.5 +/- 1.3 (n = 6) for LLF, 2.9 +/- 0.4 (n = 5) for [14C]sulpholithocholate (14C-SLC) and 4.3 +/- 0.3 (min) for [14C]lithocholic acid glucuronide (14C-LG). Plasma clearances of 14C-SLC, LLF and 14C-LG were 15.5 +/- 2.2 (n = 6), 18.1 +/- 4.2 (n = 6) and 17.8 +/- 0.5 ml/min/kg (n = 6) (P = 0.15), respectively. Biliary excretion in bile-fistula rats gave cumulative 20 min biliary output as a percentage of injected dose as follows: LLF, 71.6 +/- 0.8% (n = 10); 14C-SLC, 75.5 +/- 2.8% (n = 6) and 14C-LG, 61.7 +/- 0.5% (n = 6) (P = NS). Peak biliary excretion rates, given as % dose/2 min, were 10.2 +/- 0.3 for LLF, 13.5 +/- 0.6 for 14C-SLC and 12.8 +/- 0.4 for 14C-LG. In another group of bile-fistula rats, a 3.0 micromol/500 microl saline i.v. bolus of LLF caused a 15.4 +/- 1.9% decrease in bile flow and, similarly, sodium lithocholate in a solution of albumin caused a 17.9 +/- 1.8% (P = NS) diminution in bile flow. Despite the similar cholestatic properties of LLF and lithocholate, LLF was more soluble than lithocholate, with a relative retention time on HPLC similar to that of GLC. LLF is a divalent 'unipolar' anionic fluorescent monohydroxy bile salt analogue with physical, biological and cholestatic properties that are similar to those of lithocholate, glycolithocholate and their derivatives and thus offers a potentially useful probe for studying mechanisms of monohydroxy bile salt-induced cholestasis at the hepatocellular level.

Obstructive sleep apnoea syndrome (OSAS) as a complication of carcinoid syndrome treated successfully by hepatic artery embolization

Obstructive sleep apnoea syndrome (OSAS) appears to be an extremely rare complication of carcinoid syndrome and has not yet been reported in the literature. We describe a 75-year-old patient with a history of bronchial carcinoid who besides typical carcinoid syndrome symptoms developed sleep disturbance and day lethargy caused by massive facial and nasal tissue oedema. Sleep apnoea was confirmed by sleep study. Abdominal ultrasound and computed tomography (CT) scan showed the presence of multiple liver metastases. Because the patient did not respond to octreotide therapy, embolization of the hepatic artery was performed. After this procedure we observed dramatic improvement of the patient's life quality, and rapid disappearance of facial swelling and sleep apnoea symptoms. We conclude that hepatic artery embolization appeared to be an effective method of abolishing obstructive sleep apnoea associated with carcinoid syndrome.

Cholyllysyl fluroscein and related lysyl fluorescein conjugated bile acid analogues

There have been attempts to couple bile acids to fluorescein to permit their visualization during studies of physiology and pathophysiology. Although conjugation has been achieved by many, the product differed in many respects from the parent bile acid congener. We describe lysylfluorescein conjugated bile acid analogues (LFCBAA) synthesized in our laboratory as model divalent "unipolar" molecules. We have determined LFCBAA properties including their water:octanol partition coefficient, HPLC retention time and critical micellar concentration and compared them with their parent bile acid congeners. Cholyl lysylfluorescein (CLF) and lithocholyl lysylfluoroscein (LLF) have properties similar to cholylglycine (CG) and glycolithocholate (GLC), respectively. In human and rat hepatocytes uptake of CLF follows Michaelis-Menten kinetics with K(m) and Vmax similar to CG. Biliary excretion rates of CLF and LLF closely resemble those of CG and GLC in both normal and mutant TR- rats which lack the multiorganic anion transporter (MOAT), strongly supporting the notion that CLF and LLF are substrates for the canalicular bile salt transporter (cBST). The close similarity of hepatocyte uptake and biliary secretion of these LFCBAA and their parent bile acid congeners makes them potentially useful probes for the intracellular visualization of bile salt movement and deposition in various models of bile formation and secretion.