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1.
Aliment Pharmacol Ther ; 47(5): 657-664, 2018 03.
Article in English | MEDLINE | ID: mdl-29266346

ABSTRACT

BACKGROUND: Activated hepatic macrophages play a key role in inflammation and fibrosis progression in chronic liver disease. AIM: To assess the prognostic value of soluble (s)CD163 and mannose receptor (sMR) in cirrhotic patients and explore associations with markers of intestinal permeability (lactulose-mannitol ratio, diamine oxidase), bacterial translocation (endotoxin, lipopolysaccharide-binding protein) and markers of systemic immune activation (interleukin-6, interleukin-8, sCD14). METHODS: We prospectively investigated 101 cirrhotic patients (Child-Pugh class A: n = 72, Child-Pugh classes B and C: n = 29) and 31 healthy controls. Patients were observed for a median follow-up of 37 months. RESULTS: Median plasma levels of sCD163 and soluble mannose receptor were significantly elevated in cirrhotic patients (P < .001) and increased with disease severity (sCD163 in healthy controls = 1.3, Child-Pugh class A = 4.2, Child-Pugh classes B and C = 8.4 mg/L; sMR in healthy controls = 15.8, Child-Pugh class A = 36.5, Child-Pugh classes B and C = 66.3 µg/dL). A total of 21 patients died during the observation period. Patients with sCD163 levels above 5.9 mg/L showed significantly reduced survival (survival rate after 36 months: 71% versus 98%, P < .001). Patients with soluble mannose receptor levels above 45.5 µg/dL developed significantly more complications of cirrhosis within 12 months (73% versus 9%, P < .001). Furthermore, both variables correlated with the lactulose-mannitol ratio, diamine oxidase, lipopolysaccharide and interleukin-8. CONCLUSION: Our data demonstrate the prognostic value of sCD163 in predicting long-term survival in patients with liver cirrhosis and identify soluble mannose receptor as a prognostic marker for occurrence of cirrhosis-associated complications. The correlation between gut barrier dysfunction and activation of macrophages points towards a link between them.


Subject(s)
Antigens, CD/blood , Antigens, Differentiation, Myelomonocytic/blood , Intestinal Mucosa , Lectins, C-Type/blood , Liver Cirrhosis/diagnosis , Liver Cirrhosis/mortality , Liver Failure/diagnosis , Liver Failure/mortality , Mannose-Binding Lectins/blood , Receptors, Cell Surface/blood , Aged , Bacterial Translocation/physiology , Biomarkers/blood , Case-Control Studies , Female , Humans , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Intestines/microbiology , Liver Cirrhosis/complications , Liver Cirrhosis/metabolism , Liver Failure/etiology , Liver Failure/microbiology , Male , Mannose Receptor , Middle Aged , Permeability , Prognosis
2.
Aliment Pharmacol Ther ; 44(9): 926-935, 2016 11.
Article in English | MEDLINE | ID: mdl-27593544

ABSTRACT

BACKGROUND: Probiotics may correct intestinal dysbiosis and proinflammatory conditions in patients with liver cirrhosis. AIM: To test the effects of a multispecies probiotic on innate immune function, bacterial translocation and gut permeability. METHODS: In a randomised, double blind, placebo-controlled study, stable cirrhotic out-patients either received a daily dose of a probiotic powder containing eight different bacterial strains (Ecologic Barrier, Winclove, Amsterdam, The Netherlands) (n = 44) or a placebo (n = 36) for 6 months and were followed up for another 6 months. RESULTS: We found a significant but subclinical increase in neutrophil resting burst (2.6-3.2%, P = 0.0134) and neopterin levels (7.7-8.4 nmol/L, P = 0.001) with probiotics but not with placebo. Probiotic supplementation did not have a significant influence on neutrophil phagocytosis, endotoxin load, gut permeability or inflammatory markers. Ten severe infections occurred in total; one during intervention in the placebo group, and five and four after the intervention has ended in the probiotic and placebo group, respectively. Liver function showed some improvement with probiotics but not with placebo. CONCLUSIONS: Probiotic supplementation significantly increased serum neopterin levels and the production of reactive oxygen species by neutrophils. These findings might explain the beneficial effects of probiotics on immune function. Furthermore, probiotic supplementation may be a well-tolerated method to maintain or even improve liver function in stable cirrhosis. However, its influence on gut barrier function and bacterial translocation in cirrhotic patients is minimal.


Subject(s)
Bacterial Translocation/physiology , Gastrointestinal Absorption/physiology , Immunity, Innate/physiology , Liver Cirrhosis/drug therapy , Liver Cirrhosis/immunology , Probiotics/administration & dosage , Adult , Bacterial Translocation/drug effects , Dietary Supplements , Double-Blind Method , Female , Gastrointestinal Absorption/drug effects , Gram-Negative Bacteria/drug effects , Gram-Negative Bacteria/physiology , Humans , Immunity, Innate/drug effects , Liver Cirrhosis/microbiology , Male , Middle Aged , Permeability/drug effects , Treatment Outcome
3.
Vaccine ; 27(23): 3099-108, 2009 May 18.
Article in English | MEDLINE | ID: mdl-19428924

ABSTRACT

For the design of peptide-based vaccines against the hepatitis C virus it is essential to acquire more information on frequently recognized epitopes in patients with successful immune control of HCV in the context of different HLA types. A matrix approach using 393 15mer peptides from conserved HCV regions overlapping by 13 amino acids was applied in 52 HCV-recovered individuals. Candidate peptides were further tested in two independent laboratories. 38 peptides induced IFN-gamma responses in ELISPOT assays including 15 previously unknown epitopes. There was no particular immune dominance as only five peptides were recognized by more than three individuals. Seven out of 14 peptides tested in more detail could be confirmed to be immunogenic using ELISPOT and cytotoxicity assays. While only 33% of HCV-recovered individuals recognized recombinant HCV proteins, 81% of individuals tested positive in the matrix approach (p<0.001). The strength, frequency and breadth of HCV-specific T cell responses were similar in spontaneously recovered patients than in interferon-recovered patients. In conclusion (i) we identified novel HCV epitopes in conserved regions, (ii) confirmed the inter-individual diversity of HCV-specific T cell responses and (iii) found no significant differences in HCV-specific T cell responses between spontaneously recovered and IFN-recovered patients.


Subject(s)
Hepacivirus/chemistry , Hepacivirus/immunology , Hepatitis C/immunology , T-Lymphocytes/immunology , Adult , Aged , Amino Acid Sequence , Conserved Sequence , Epitopes/immunology , Female , Genome, Viral , Hepacivirus/genetics , Humans , Lymphocyte Activation , Male , Middle Aged , Remission, Spontaneous
4.
Int J Clin Pract ; 62(12): 1851-7, 2008 Dec.
Article in English | MEDLINE | ID: mdl-17927765

ABSTRACT

AIMS: To study whether circulatory changes during large volume paracentesis (LVP) in patients with liver cirrhosis and tense ascites as assessed by novel non-invasive haemodynamic measuring technology are reversed by subsequent albumin infusion. MATERIALS AND METHODS: Eleven patients with portal hypertensive ascites secondary to liver cirrhosis of Child's class B or C were studied during LVP (10.7 +/- 4.4 l) and subsequent infusion of albumin. Digital arterial pulse waves were continuously measured by vascular unloading technique providing data for beat-to-beat values of systolic (P(s)), diastolic (P(d)) and mean arterial pressures (P(m)), respectively, as well as for heart rate (F(h)), stroke volume (V(s)), cardiac output (Q(co)) and peripheral resistance (R). Data extrapolated to the end of paracentesis, albumin infusion and follow-up phases were compared with the end of the equilibration phase. RESULTS: At the end of paracentesis, P(s), P(m) and P(d) changed by -14 +/- 15% (p < 0.05), -16 +/- 11% (p < 0.01) and -17 +/- 11% (p < 0.001), respectively, whereas Q(co) and F(h) did not change substantially. There was a highly significant increase in V(s) by +21 +/- 25% (p < 0.01). The largest change was seen in R which significantly decreased by -29 +/- 24% (p < 0.01). This change was not reversed by infusion of albumin and persisted up to the end of follow-up. CONCLUSION: The haemodynamic changes following LVP appear to be first and foremost controlled by changes in peripheral resistance with insufficient cardiac compensation. Further studies combining albumin with vasopressors for prevention of paracentesis-induced circulatory changes are needed.


Subject(s)
Albumins/administration & dosage , Ascites/therapy , Hemodynamics/physiology , Paracentesis/methods , Aged , Ascites/physiopathology , Blood Pressure/physiology , Female , Heart Rate/physiology , Humans , Hypertension, Portal/etiology , Liver Cirrhosis/complications , Male , Middle Aged , Stroke Volume/physiology , Vascular Resistance/physiology
5.
Gut ; 57(1): 77-83, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17698861

ABSTRACT

BACKGROUND: The severity of hepatic encephalopathy is currently graded clinically using West Haven criteria and psychometric tests. OBJECTIVE: To assess the discriminative power of the bispectral index (BIS) monitor to classify the degree and progression of hepatic encephalopathy. DESIGN: A consecutive, multicentre, observer blinded validation study. SETTING: Medical University of Graz (Graz, Austria), Zhejiang University First Affiliated Hospital (Hang Zhou, China), and Cairo University (Cairo, Egypt). PATIENTS: 28 consecutive patients with hepatic encephalopathy were first enrolled at Medical University of Graz as a test set. The estimated BIS cut off values were subsequently tested in a validation set of 31 patients at Zhejiang University First Affiliated Hospital and 26 patients at Cairo University; 18 patients were reassessed later in a longitudinal study. Fifteen of 85 patients (18%) were excluded from the final analysis (11 became too agitated with high electromyographic activity; four fell asleep during the recording). RESULTS: Applying the Austrian BIS cut off values of 85, 70, and 55 for discriminating West Haven grades 1 to 4 yielded agreement between BIS classification and West Haven grades in 40 of the 46 validation patients (87%), and in 16 of the 18 follow up patients (89%). Mean (SD) BIS values differed significantly between patients with West Haven grade 1 (90.2 (2.5)), grade 2 (78.4 (6.6)), grade 3 (63.2 (4.8)), and grade 4 (45.4 (5.0)). CONCLUSIONS: BIS is a useful measure for grading and monitoring the degree of involvement of the central nervous system in patients with chronic liver disease.


Subject(s)
Hepatic Encephalopathy/diagnosis , Aged , Ammonia/blood , Female , Hepatitis C, Chronic/complications , Humans , Male , Middle Aged , Sensitivity and Specificity , Spectrum Analysis/methods , Spectrum Analysis/standards
6.
Br J Pharmacol ; 151(5): 580-90, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17471184

ABSTRACT

Binding and transport of a number of endogenous and exogenous compounds is an important function of the main plasma protein, albumin. In vivo and in vitro, albumin may be oxidatively modified in different ways with different agents at different sites. These modifications have various consequences on the physiological functions of albumin. Diabetes mellitus, liver diseases and nephropathy are just a few examples of disorders in which oxidative stress is involved and altered albumin functions have been described. This review is focussed on the consequences of oxidative modification on the binding properties of albumin. These range from no effect to decreased or increased binding affinities depending on the ligand under investigation and the type of modification. Indicators for modification include glycosylation, disulphide formation or the content of carbonyl groups. The redox state of albumin can affect the binding properties in several ways, including altered conformation and consequently altered affinities at binding sites and altered binding when the binding reaction itself is redox sensitive. The physiological or pathophysiological concentrations of different oxidatively modified albumin molecules vary over a wide range and are crucial in assessing the clinical relevance of altered ligand binding properties of a particularly modified albumin species in various disease conditions.


Subject(s)
Protein Binding/physiology , Serum Albumin/chemistry , Serum Albumin/metabolism , Humans , Oxidation-Reduction , Oxidative Stress/physiology
10.
J Clin Microbiol ; 39(5): 1788-90, 2001 May.
Article in English | MEDLINE | ID: mdl-11325991

ABSTRACT

In this study, we compared serum hepatitis C virus (HCV) RNA concentrations with HCV RNA concentrations in whole blood collection tubes, including two different types of EDTA tubes and nucleic acid stabilization tubes (NASTs). We also investigated the impact of a processing delay on HCV RNA concentration in these tubes. In NASTs, the mean HCV RNA concentration was comparable to the mean serum HCV RNA concentration at "date zero." In EDTA tubes, mean baseline HCV RNA concentrations were higher. Storage at room temperature up to 96 h did not result in a decline of HCV RNA concentration in any of the whole blood collection tubes. In NASTs, HCV RNA concentrations remained stable during the whole study period, whereas a significant increase of HCV RNA was observed in both types of EDTA tubes at 96 h compared to date zero. We concluded that HCV RNA remains stable in NASTs at room temperature for at least 96 h, allowing greater flexibility in sample collection and transport.


Subject(s)
Blood Specimen Collection , Blood/virology , Hepacivirus/isolation & purification , Hepatitis C/virology , RNA, Viral/blood , Adult , Blood Specimen Collection/instrumentation , Blood Specimen Collection/methods , Female , Humans , Male , Middle Aged
11.
Hepatology ; 33(3): 633-46, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11230744

ABSTRACT

Reduced hepatobiliary transporter expression could explain impaired hepatic uptake and excretion of bile salts and other biliary constituents resulting in cholestasis and jaundice. Because little is known about alterations of hepatobiliary transport systems in human cholestatic liver diseases, it was the aim of this study to investigate such potential changes. Hepatic mRNA levels in hepatobiliary transport systems for bile salts (NTCP, BSEP), organic anions (OATP2, MRP2, MRP3), organic cations (MDR1), phospholipids (MDR3), and aminophospholipids (FIC1) were determined in 37 human liver biopsies and control livers by competitive reverse-transcription polymerase chain reaction (RT-PCR). Transporter tissue distribution was investigated by immunofluorescence microscopy. In patients with inflammation-induced icteric cholestasis (mainly cholestatic alcoholic hepatitis), mRNA levels of NTCP, OATP2, and BSEP were reduced by 41% (P <.001), 49% (P <.005), and 34% (P <.05) compared with controls, respectively. In addition, NTCP and BSEP immunostaining was reduced. MRP2 mRNA levels remained unchanged, but canalicular immunolabeling for MRP2 was also decreased. mRNA expression of MRP3, MDR1, MDR3, and FIC1 remained unchanged. In contrast to the alterations of transporter expression in inflammation-induced icteric cholestasis, transporter expression did not change in anicteric cholestasis caused by primary biliary cirrhosis (PBC) stages I and II. In conclusion, reduced expression of hepatobiliary transport systems for bile salts and other organic anions may contribute to inflammation-induced cholestasis in humans. Reduction of transporter gene expression can occur at the mRNA level as observed for NTCP, OATP2, and BSEP. However, reduced MRP2 immunostaining in the presence of conserved MRP2 mRNA levels suggests an additional role for posttranscriptional/posttranslational mechanisms.


Subject(s)
Bile Ducts/metabolism , Carrier Proteins/metabolism , Cholestasis/metabolism , Liver/metabolism , ATP Binding Cassette Transporter, Subfamily B/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , ATP-Binding Cassette Transporters/metabolism , Adenosine Triphosphatases/genetics , Adult , Anions/metabolism , Bile Acids and Salts/metabolism , Biopsy , Carrier Proteins/genetics , Cholestasis/pathology , Female , Fluorescent Antibody Technique , Humans , Liver/pathology , Male , Middle Aged , RNA, Messenger/metabolism , Reference Values
12.
Can J Gastroenterol ; 14 Suppl D: 99D-104D, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11110621

ABSTRACT

Hepatic uptake and excretion of bile salts and several nonbile salt organic anions (eg, bilirubin) are mediated by a distinct set of polarized transport systems at the basolateral and apical plasma membrane domains of hepatocytes and bile duct epithelial cells (cholangiocytes). With the increasing availability of molecular probes for these transporters, evidence now exists that decreased or even absent expression of hepatobiliary transport proteins in hepatocytes or cholangiocytes may explain impaired transport function that results in hyperbilirubinemia and cholestasis. This review summarizes the molecular defects in hepatocellular membrane transporters that are associated with hereditary and acquired forms of cholestatic liver disease.


Subject(s)
Bile Acids and Salts/metabolism , Carrier Proteins/physiology , Cholestasis/metabolism , Hepatocytes/physiology , Liver/metabolism , Bile/metabolism , Cholestasis/genetics , Cholestasis/physiopathology , Humans
13.
Clin Diagn Lab Immunol ; 7(5): 853-5, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10973470

ABSTRACT

The Cobas Amplicor HBV Monitor test for quantitative determination of hepatitis B virus (HBV) DNA in serum has recently been introduced. To evaluate the performance of this assay in a routine diagnostic laboratory, reproducibility of results was determined with the First European Union Concerted Action HBV Proficiency Panel and the Accurun 325 HBV DNA Positive Control, Series 300. Results for 270 routine serum samples were additionally evaluated. To avoid the retesting of a large number of samples due to titers exceeding the upper limit for the linear range of the assay, sera of patients with chronic hepatitis B (CHB) were diluted prior to the assay to 10(-4) in normal human plasma, which is included in the assay. The mean coefficient of variation was 22.9% for all input HBV DNAs. Of 270 routine serum samples, 182 (150 sera from transplant donors and 32 sera from patients who had recovered from CHB) tested negative. Eighty-six sera were found to be HBV DNA positive; in six sera, HBV DNA levels were found to exceed the upper limit for the linear range of the assay and had to be retested. In the remaining two sera, inhibition occurred. The semiautomated Cobas Amplicor HBV Monitor test showed sufficient reproducibility and helped in avoiding human error. The relatively narrow linear range of detection is a limitation of the new assay.


Subject(s)
DNA, Viral/blood , Hepatitis B, Chronic/virology , Polymerase Chain Reaction/methods , Reagent Kits, Diagnostic , Automation , Diagnostic Tests, Routine , Hepatitis B virus/genetics , Hepatitis B, Chronic/blood , Hepatitis B, Chronic/diagnosis , Humans , Laboratories , Reproducibility of Results
14.
Eur J Gastroenterol Hepatol ; 12(7): 813-6, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10929912

ABSTRACT

Portal venous decompression with transjugular intra-hepatic portosystemic shunt (TIPS) is a new approach in the treatment of Budd-Chiari syndrome. We report on a 31-year-old female with Budd-Chiari syndrome due to anti-phospholipid antibodies with compression of the inferior vena cava treated with TIPS and stenting of the inferior vena cava. TIPS was complicated by massive intra-hepatic haematoma which was managed conservatively. Treatment options and pathogenic mechanisms of Budd-Chiari syndrome under the rare coincidence of aplastic anaemia and anti-phospholipid syndrome are discussed. TIPS may be considered for venous decompression in Budd-Chiari syndrome, but physicians should be aware of potential TIPS' complications in these patients.


Subject(s)
Budd-Chiari Syndrome/surgery , Hematoma/etiology , Liver Diseases/etiology , Portasystemic Shunt, Transjugular Intrahepatic/adverse effects , Adult , Anemia, Aplastic/complications , Anemia, Aplastic/diagnosis , Angiography , Antibodies, Antiphospholipid/blood , Anticoagulants/administration & dosage , Budd-Chiari Syndrome/complications , Budd-Chiari Syndrome/diagnosis , Female , Follow-Up Studies , Hematoma/diagnostic imaging , Hematoma/drug therapy , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/diagnosis , Humans , Liver Diseases/diagnostic imaging , Liver Diseases/drug therapy , Liver Function Tests , Portasystemic Shunt, Transjugular Intrahepatic/methods , Treatment Outcome , Ultrasonography
15.
Clin Physiol ; 20(3): 225-33, 2000 May.
Article in English | MEDLINE | ID: mdl-10792416

ABSTRACT

Impairments in muscle power production and recovery following short-duration intense activity could lead to decreased performance and risk of injury. We developed a power test for the knee extensor muscles using torque-velocity testing and moderate isotonic loads. Twenty-eight female volunteers performed three maximal efforts at each of four isotonic loads (27.1, 40.6, 54.2 and 67.8 N. m). If the calculated regression line for the torque-velocity data had an r2 >/= 0.95 (i.e. an acceptable test), maximal power (408 +/- 56 W) was computed from the data. Immediately after torque-velocity testing, the subjects repeated maximal effort knee extensions with 33.9 N. m for three bouts of 15 repetitions with 15 s of rest to produce muscle fatigue, defined as a decrease in power output during isotonic exercise. After a 4 min rest, the torque-velocity test was repeated and power calculated (345 +/- 48 W). For the group, the recovery of maximal power after the fatigue protocol was 85%. The extremes were represented by one subject who recovered only 70% of her maximal power and another who recovered completely (>98%). Physiological differences in muscle power following repeated exercise could have an impact on the outcome of therapeutic interventions for sports injuries, fatigue syndromes and occupational over-use conditions.


Subject(s)
Exercise/physiology , Knee Injuries/etiology , Knee Joint/physiology , Muscle Fatigue/physiology , Adult , Biomechanical Phenomena , Female , Humans , Isotonic Contraction , Knee Injuries/physiopathology , Muscle, Skeletal/physiology , Weight-Bearing
16.
Clin Diagn Lab Immunol ; 7(2): 298-300, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10702509

ABSTRACT

The level of hepatitis B virus (HBV) DNA in serum reflects the replicative activity of HBV. To compare serum HBV DNA levels in different states of hepatitis B, 47 sera of patients with HBeAg-positive chronic hepatitis B, 4 sera of patients with HBeAg-negative chronic hepatitis B, 40 samples of patients after HBeAg seroconversion during alpha interferon treatment, 57 sera of inactive HBsAg carriers, and 42 sera of patients who had recovered from chronic hepatitis B more than 12 months prior to blood collection were checked for the presence of HBV DNA with the Amplicor HBV Monitor Test. In patients with HBeAg-positive chronic hepatitis B, the median of serum HBV DNA levels (8.3 x 10(8) copies/ml) was significantly higher than that for patients after HBeAg seroconversion (6.2 x 10(3) copies/ml) and than that for inactive HBsAg carriers (5.6 x 10(3) copies/ml). None of the patients who had recovered from hepatitis B had detectable HBV DNA in serum. Quantitative PCR proved to be a valuable tool for identification of different states of HBV infection. This technique was found to be a good method for determination of serum HBV DNA levels both for patients with HBeAg seroconversion and for inactive carriers who showed low viremia not detectable by conventional hybridization assays.


Subject(s)
DNA, Viral/blood , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Polymerase Chain Reaction , Adolescent , Adult , Aged , Child , Female , Hepatitis B virus/isolation & purification , Hepatitis B, Chronic/blood , Hepatitis B, Chronic/physiopathology , Humans , Male , Middle Aged , Polymerase Chain Reaction/methods , Viral Load
17.
J Gastroenterol Hepatol ; 14(10): 946-59, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10530489

ABSTRACT

Inflammatory cytokines produced in response to various infectious and non-infectious stimuli are potent inducers of intrahepatic cholestasis (inflammation-induced cholestasis). The cholestatic effect of cytokines results mainly from inhibition of expression and function of hepatocellular transport systems which normally mediate hepatic uptake and biliary excretion of bile salts and various non-bile salt organic anions (e.g. bilirubin). These cytokine effects are reversible and bile secretory function is restored upon disappearance of the inflammatory injury. This review summarizes the clinical, pathophysiological and molecular aspects of inflammation-induced cholestasis.


Subject(s)
Cholestasis/etiology , Inflammation/complications , Adult , Biological Transport/drug effects , Child , Cholestasis/blood , Cytokines/blood , Cytokines/toxicity , Endotoxins/blood , Endotoxins/toxicity , Hepatitis/blood , Hepatitis/complications , Humans , Infections/blood , Infections/complications , Paraneoplastic Syndromes/complications , Parenteral Nutrition, Total/adverse effects , Postoperative Complications
18.
Z Gastroenterol ; 37(7): 639-47, 1999 Jul.
Article in German | MEDLINE | ID: mdl-10458013

ABSTRACT

Hepatic uptake and biliary excretion of bile salts and non-bile salt organic anions (e.g., bilirubin) is mediated by specific transport proteins located at the basolateral and canalicular membranes of hepatocytes. Several hepatobiliary transport systems have been identified and cloned over the past years. This development has facilitated molecular biological and genetic analyses of these transporters in experimental cholestasis and human cholestatic liver diseases. Evidence now exists that decreased or even absent expression of hepatobiliary transport systems may explain impaired transport function resulting in hyperbilirubinemia and cholestasis. This review summarizes the molecular defects in hepatocellular membrane transporters associated with hereditary and acquired forms of cholestatic liver diseases. The increasing information on the molecular regulation of hepatobiliary transport systems should bring new insights into the pathophysiology and treatment of human cholestatic liver diseases.


Subject(s)
Bile Acids and Salts/metabolism , Bilirubin/metabolism , Carrier Proteins/genetics , Cholestasis/genetics , Liver Cirrhosis, Biliary/genetics , ATP Binding Cassette Transporter, Subfamily B/genetics , ATP-Binding Cassette Transporters/genetics , Cholestasis/diagnosis , Humans , Liver Cirrhosis, Biliary/diagnosis , Point Mutation
19.
Br J Pharmacol ; 125(6): 1120-7, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9863637

ABSTRACT

The vasopressin receptor subtype involved in the enhancement by vasopressin of adrenoceptor-mediated vasoconstriction was investigated in rat isolated perfused mesenteric arteries. [Arg8]vasopressin (1-10 nM) dose-dependently increased the perfusion pressure and enhanced the pressor response to the adrenoceptor agonist methoxamine (40 nmol) or electrical stimulation of periarterial nerves (16 Hz), at the concentration of 10 nM of [Arg8]vasopressin up to 4 and 3 fold, respectively. During prolonged exposure (45 min) the direct vasoconstrictor effect of [Arg8]vasopressin (10 nM) rapidly declined whereas the potentiation of methoxamine-induced vasoconstriction was maintained. The selective vasopressin V1A receptor antagonist SR 49,059 (1-3 nM) and the non-selective V1A/B and oxytocin receptor antagonist [deamino-Pen1,Tyr(Me)2,Arg8]vasopressin (15-45 nM) inhibited the direct vasoconstrictor action of [Arg8]vasopressin but had no effect on the enhancement of the pressor response to methoxamine or electrical stimulation. The V1B receptor agonist [deamino-Cys1,beta-(3-pyridyl)-D-Ala2,Arg8]vasopressin (100-1000 nM) and the V2 receptor agonist [deamino-Cys1,D-Arg8]vasopressin (1-10 nM) were devoid of any pressor activity and did not potentiate methoxamine-evoked vasoconstriction. In contrast, [1-triglycyl,Lys8]vasopressin (100 - 1000 nM) potentiated the methoxamine responses without per se inducing vasoconstriction. In arteries precontracted with methoxamine (7.5 microM) pressor responses to [Arg8]vasopressin (3-10 nM) were not inhibited by a dose of SR 49,059 (3 nM) which abolished the peptide's vasoconstrictor effect under control conditions. These data show that the direct vasoconstrictor effect of [Arg8]vasopressin is mediated by V1A receptors while the enhancement of adrenoceptor-mediated pressor responses is insensitive to V1A, V1B, and oxytocin receptor antagonists and is not mimicked by selective agonists of V1B and V2 receptors. In conclusion, an unusual interaction of vasopressin with V1A receptors, or even the existence of a novel receptor subtype, has to be considered.


Subject(s)
Antidiuretic Hormone Receptor Antagonists , Arginine Vasopressin/pharmacology , Hormone Antagonists/pharmacology , Indoles/pharmacology , Mesenteric Arteries/drug effects , Mesenteric Arteries/ultrastructure , Pressoreceptors/physiology , Pyrrolidines/pharmacology , Receptors, Adrenergic/physiology , Vasoconstriction/drug effects , Vasoconstrictor Agents/pharmacology , Animals , Blood Pressure/drug effects , Drug Synergism , Male , Mesenteric Arteries/physiology , Methoxamine/pharmacology , Perfusion , Pressoreceptors/drug effects , Rats , Rats, Sprague-Dawley , Receptors, Adrenergic/drug effects , Vasoconstriction/physiology
20.
Am J Gastroenterol ; 93(10): 1985-6, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9772072

ABSTRACT

Primary biliary cirrhosis (PBC) is an autoimmune disease of the liver frequently associated with extrahepatic autoimmune phenomena. Specific antibodies against platelet glycoproteins may play an important role in the pathogenesis of thrombocytopenia associated with PBC. This is the first report of life-threatening idiopathic thrombocytopenic purpura successfully treated with steroids in a 62-yr-old woman 2 yr after liver transplantation for PBC.


Subject(s)
Glucocorticoids/therapeutic use , Liver Cirrhosis, Biliary/surgery , Liver Transplantation , Postoperative Complications/drug therapy , Prednisolone/therapeutic use , Purpura, Thrombocytopenic, Idiopathic/drug therapy , Female , Humans , Middle Aged , Postoperative Complications/immunology , Purpura, Thrombocytopenic, Idiopathic/immunology
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