GNB3 C825T-Polymorphismus bei dilatativer Kardiomyopathie

1998 konnten Siffert et al. einen C825T-Polymorphismus im Gen GNB3 nachweisen, das für die GNB3-Untereinheit heterotrimerer G-Proteine kodiert. Das 825T-Allel verursacht ein alternatives Spleißen des Gens und die Expression einer funktionell aktiven Deletionsvariante von GNB3, welche als Gß3s bezeichnet wird. Das 825T-Allel ist mit einem erhöhten Risiko für arterielle Hypertonie bei Weißen assoziiert, vermutlich mit der sogenannten Form der “low-Renin-hypertension”, und es akkumuliert besonders bei Hypertonikern mit positiver Familienanamnese. Dabei scheint diese Abnormalität ferner mit einer peripheren Insulinresistenz, einem erhöhten Body-Mass-Index, einer Linksherzhypertrophie, einer gesteigerten Nephropathieneigung bei Typ-1-Diabetes, einer verstärkten Chemotaxis neutrophiler Granulozyten und einer veränderten Kaliumkanal-Aktivität im Vorhof zu korrelieren. Die dilatative Kardiomyopathie stellt die häufigste Form der Kardiomyopathien dar. Für einen nicht unerheblichen Teil wird mittlerweile eine erbliche Genese angenommen. Die einzige kausale Therapie besteht derzeit in einer Herztransplantation. Ziel der vorliegenden Arbeit war die Klärung der Frage, ob eine genetische Disposition - im Hinblick auf den oben genannten Polymorphismus - für eine dilatative Kardiomyopathie mit nachfolgender Herztransplantation besteht. Wir extrahierten hierfür DNA aus insgesamt 89 explantierten Herzen von Patienten mit Kardiomyopathie und amplifizierten GNB3-spezifische Abschnitte mittels PCR. Das PCR-Produkt wurde mittels Restriktionsanalyse auf den Genotyp hin überprüft. Durch die im Anschluss durchgeführte Gelelektrophorese konnten wir anhand der Bandenmuster den Genotyp der Patienten für GNB3 identifizieren. Diese Daten wurden zum Schluss in eine Access Datenbank eingegeben und statistisch ausgewertet. Wir kamen zu folgenden Ergebnissen: Patienten mit dem TT-Genotyp waren im Vergleich zu normalen C825-Allelträgern tendenziell häufiger von einer dilatativen Kardiomyopathie betroffen, hatten ein schnelleres Fortschreiten der Erkrankung, einen höheren Pulmonalarteriendruck und einen häufigeren Bedarf an Glykosiden, Diuretika, Antiarrhythmika und Kalzium-Antagonisten. Diese Ergebnisse waren statistisch jedoch nicht signifikant. Als Gründe für das Nichterreichen der statistischen Signifikanz sind folgende Punkte zu nennen, die unsere Studie limitierten: 1. das zu kleine Kollektiv von 89 Patienten. 2. die niedrige Frequenz des TT-Genotyps und 3. die geringe Zahl von Herztransplantationen (im Jahr 2000 nur 418 Herzen)

Bioelectrical impedance analysis in clinical practice: implications for hepatitis C therapy BIA and hepatitis C

<p>Abstract</p> <p>Background</p> <p>Body composition analysis using phase angle (PA), determined by bioelectrical impedance analysis (BIA), reflects tissue electrical properties and has prognostic value in liver cirrhosis. Objective of this prospective study was to investigate clinical use and prognostic value of BIA-derived phase angle and alterations in body composition for hepatitis C infection (HCV) following antiviral therapy.</p> <p>Methods</p> <p>37 consecutive patients with HCV infection were enrolled, BIA was performed, and PA was calculated from each pair of measurements. 22 HCV genotype 3 patients treated for 24 weeks and 15 genotype 1 patients treated for 48 weeks, were examined before and after antiviral treatment and compared to 10 untreated HCV patients at 0, 24, and 48 weeks. Basic laboratory data were correlated to body composition alterations.</p> <p>Results</p> <p>Significant reduction in body fat (BF: 24.2 ± 6.7 kg vs. 19.9 ± 6.6 kg, genotype1; 15.4 ± 10.9 kg vs. 13.2 ± 12.1 kg, genotype 3) and body cell mass (BCM: 27.3 ± 6.8 kg vs. 24.3 ± 7.2 kg, genotype1; 27.7 ± 8.8 kg vs. 24.6 ± 7.6 kg, genotype 3) was found following treatment. PA in genotype 3 patients was significantly lowered after antiviral treatment compared to initial measurements (5.9 ± 0.7° vs. 5.4 ± 0.8°). Total body water (TBW) was significantly decreased in treated patients with genotype 1 (41.4 ± 7.9 l vs. 40.8 ± 9.5 l). PA reduction was accompanied by flu-like syndromes, whereas TBW decline was more frequently associated with fatigue and cephalgia.</p> <p>Discussion</p> <p>BIA offers a sophisticated analysis of body composition including BF, BCM, and TBW for HCV patients following antiviral regimens. PA reduction was associated with increased adverse effects of the antiviral therapy allowing a more dynamic therapy application.</p

Sarcoidosis of the Intra- and Extrahepatic Bile Ducts with Concomitant Cholangitis in a Patient with Ulcerative Colitis

Cholangitis in patients with ulcerative colitis (UC) can lead to misdiagnosis of primary sclerosing cholangitis (PSC). Furthermore, it can mimic cholangiocellular carcinoma, which also can lead to inappropriate and potentially harmful treatment of the patient. An 18-year-old male patient with known UC presented with pain in his right upper abdomen and elevation of the cholestatic liver enzymes (alkaline phosphatase: 197 U/L, γ-glutamyltransferase: 229 U/L) and increased inflammatory parameters (leukocytosis and CrP of 13.6 mg/L). Magnetic resonance cholangiopancreatography revealed unclear stenosis in the bifurcation of the main hepatic bile duct as well as in the prepapillary bile duct. Ultrasound (US) examination and endoscopic retrograde cholangiopancreatography showed dilatation of the intra -and extrahepatic bile ducts, which raised the suspicion of PSC. US image with dilated intra- and extrahepatic dilatation of the bile duct was also suggestive for autoimmune cholangitis. However, serum analysis revealed an elevated soluble interleukin-II receptor (1,305 U/mL), while immunoglobulin G4 was within normal ranges. Liver biopsy demonstrated hepatic inflammation and presence of granulomatous cells within the portal fields – convenient to sarcoidosis. After starting treatment with steroids, we observed a rapid clinical response with improvement of the dilated bile ducts and decrease of the initially elevated cholestatic liver enzymes. Sarcoidosis within the bile duct is a rare condition. Steroids are the treatment of choice and – along with the histology – are furthermore helpful to differentiate between several potential differential diagnoses like IgG4 cholangitis, primary biliary cholangitis, or PSC

TRAIL mediates liver injury by the innate immune system in the bile duct-ligated mouse.

The contribution of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a death ligand expressed by cells of the innate immune system, to cholestatic liver injury has not been explored. Our aim was to ascertain if TRAIL contributes to liver injury in the bile duct-ligated (BDL) mouse. C57/BL6 wild-type (wt), TRAIL heterozygote (TRAIL(+/-)), and TRAIL knockout (TRAIL(-/-)) mice were used for these studies. Liver injury and fibrosis were examined 7 and 14 days after BDL, respectively. Hepatic TRAIL messenger RNA (mRNA) was 6-fold greater in BDL animals versus sham-operated wt animals (P \u3c 0.01). The increased hepatic TRAIL expression was accompanied by an increase in liver accumulation of natural killer 1.1 (NK 1.1)-positive NK and natural killer T (NKT) cells, the predominant cell types expressing TRAIL. Depletion of NK 1.1-positive cells reduced hepatic TRAIL mRNA expression and serum alanine aminotransferase (ALT) values. Consistent with a role for NK/NKT cells in this model of liver injury, stress ligands necessary for their recognition of target cells were also up-regulated in hepatocytes following BDL. Compared to sham-operated wt mice, BDL mice displayed a 13-fold increase in terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and an 11-fold increase in caspase 3/7-positive hepatocytes (P \u3c 0.01). The number of TUNEL and caspase 3/7-positive cells was reduced by \u3e80% in BDL TRAIL knockout animals (P \u3c 0.05). Likewise, liver histology, number of bile infarcts, serum ALT values, hepatic fibrosis, and animal survival were also improved in BDL TRAIL(-/-) animals as compared to wt animals. Conclusion: These observations support a pivotal role for TRAIL in cholestatic liver injury mediated by NK 1.1-positive NK/NKT cells

Overexpression of mcl-1 attenuates liver injury and fibrosis in the bile duct-ligated mouse.

Hepatocyte apoptosis contributes to liver injury and fibrosis after cholestatic injury. Our aim was to ascertain if the anti-apoptotic protein Mcl-1 alters liver injury or fibrosis in the bile duct-ligated mouse. Markers of apoptosis and fibrosis were compared in wild-type and transgenic mice expressing human Mcl-1 after bile duct ligation. Compared to hMcl-1 transgenic animals, ligated wild-type mice displayed a significant increase in TUNEL-positive cells and in caspase 3/7-positive hepatocytes. Consistent with apoptotic injury, the pro-apoptotic protein Bak underwent a conformational change to an activated form upon cholestatic injury, a change mitigated by hMcl-1 overexpression. Likewise, liver histology, number of bile infarcts, serum ALT values, markers of hepatic fibrosis, and animal survival were improved in bile duct-ligated mice transgenic for hMcl-1 as compared to wild-type mice. In conclusion, increased Mcl-1 expression plays a role in hepatoprotection upon cholestatic liver injury

JNK1-dependent PUMA expression contributes to hepatocyte lipoapoptosis.

Free fatty acids (FFA) induce hepatocyte lipoapoptosis by a c-Jun N-terminal kinase (JNK)-dependent mechanism. However, the cellular processes by which JNK engages the core apoptotic machinery during lipotoxicity, especially activation of BH3-only proteins, remain incompletely understood. Thus, our aim was to determine whether JNK mediates induction of BH3-only proteins during hepatocyte lipoapoptosis. The saturated FFA palmitate, but not the monounsaturated FFA oleate, induces an increase in PUMA mRNA and protein levels. Palmitate induction of PUMA was JNK1-dependent in primary murine hepatocytes. Palmitate-mediated PUMA expression was inhibited by a dominant negative c-Jun, and direct binding of a phosphorylated c-Jun containing the activator protein 1 complex to the PUMA promoter was identified by electrophoretic mobility shift assay and a chromatin immunoprecipitation assay. Short hairpin RNA-targeted knockdown of PUMA attenuated Bax activation, caspase 3/7 activity, and cell death. Similarly, the genetic deficiency of Puma rendered murine hepatocytes resistant to lipoapoptosis. PUMA expression was also increased in liver biopsy specimens from patients with non-alcoholic steatohepatitis as compared with patients with simple steatosis or controls. Collectively, the data implicate JNK1-dependent PUMA expression as a mechanism contributing to hepatocyte lipoapoptosis

Death receptor 5 internalization is required for lysosomal permeabilization by TRAIL in malignant liver cell lines.

BACKGROUND & AIMS: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) cytotoxicity in hepatocellular carcinoma cells is mediated by lysosomal permeabilization. Our aims were to determine which TRAIL receptor, death receptor (DR) 4 or DR5, mediates lysosomal permeabilization and assess whether receptor endocytosis followed by trafficking to lysosomes contributes in this process. METHODS: TRAIL ligand internalization in Huh-7 cells was examined by confocal microscopy using Flag-tagged TRAIL, whereas DR4- and DR5-enhanced green fluorescent protein internalization was assessed by total internal reflection microscopy. Clathrin-dependent endocytosis was inhibited by expressing dominant negative dynamin. RESULTS: Although Huh-7 cells express both TRAIL receptors, short hairpin RNA silencing of DR5 but not DR4 attenuated TRAIL-mediated lysosomal permeabilization and apoptosis. The TRAIL/DR5 complex underwent rapid cellular internalization upon ligand stimulation, whereas the TRAIL/DR4 complex was not efficiently internalized. DR5-enhanced green fluorescent protein internalization was dependent on a dileucine-based internalization motif. Endocytosis of the TRAIL/DR5 complex was dynamin dependent and was required for rapid lysosomal permeabilization and apoptosis in multiple malignant hepatocellular and cholangiocarcinoma cell lines. Upon TRAIL treatment, DR5 colocalized with lysosomes after internalization. Inhibition of DR5 trafficking to lysosomes by Rab7 small interfering RNA also reduced TRAIL-mediated lysosomal disruption and apoptosis. CONCLUSIONS: TRAIL-mediated endocytosis of DR5 with trafficking to lysosomes contributes to lysosomal protease release into the cytosol and efficient apoptosis in malignant liver cell lines

High discontinuation rate of azathioprine in autoimmune hepatitis, independent of time of treatment initiation

Contains fulltext : 225262.pdf (Publisher’s version ) (Open Access)BACKGROUND: Guidelines regarding treatment for autoimmune hepatitis (AIH) favour two strategies for azathioprine (AZA) introduction: concurrent with steroids at induction or delayed by 2-4 weeks. The safety and efficacy of both strategies have been unexplored. METHODS: We established a cohort of 900 AIH patients from 12 centres in 7 European countries. There were 631 patients who used AZA as part of the therapeutic regimen. We distinguished two groups: patients with early AZA (<2 weeks) or delayed AZA initiation (≥2 weeks). Primary outcome was discontinuation of AZA in the first year of treatment. Cox regression and propensity score matching was performed to determine difference in outcomes between groups. RESULTS: Patients with early AZA initiation had significantly lower transaminases and bilirubin at baseline. Discontinuation rates of AZA did not differ between early and delayed starters (16.6% vs 14.2%), which did not reach statistical significance (hazard ratio 0.97, 95% confidence interval 0.61-1.55, P = .90). Stratification according to baseline disease activity or propensity score matching did not alter the results. Main reason for AZA discontinuation was intolerance to treatment (14.0% vs 13.2%, P = .78) with nausea and vomiting as main side effects. AIH remission rates were comparable among groups. CONCLUSION: The discontinuation rate of AZA in AIH treatment is ~15% in the first year of treatment. Early or delayed AZA initiation does not differ in remission and discontinuation rates in AIH induction therapy. Our data suggest that either strategy may be used as part of AIH treatment

Diagnostic Dilemma in a Patient with Jaundice: How to Differentiate between Autoimmune Pancreatitis, Primary Sclerosing Cholangitis and Pancreas Carcinoma

A 68-year-old male patient was referred to our institution in May 2011 for a suspected tumor in the pancreatic head with consecutive jaundice. Using magnetic resonance imaging, further differentiation between chronic inflammation and a malignant process was not possible with certainty. Apart from cholestasis, laboratory studies showed increased values for CA 19-9 to 532 U/ml (normal <37 U/ml) and hypergammaglobulinemia (immunoglobulin G, IgG) of 19.3% (normal 8.0–15.8%) with an elevation of the IgG4 subtype to 2,350 mg/l (normal 52–1,250 mg/l). Endoscopic retrograde cholangiopancreatography revealed a prominent stenosis of the distal ductus hepaticus communis caused by pancreatic head swelling and also a bihilar stenosis of the main hepatic bile ducts. Cytology demonstrated inflammatory cells without evidence of malignancy. Under suspicion of autoimmune pancreatitis with IgG4-associated cholangitis, immunosuppressive therapy with steroids and azathioprine was started. Follow-up endoscopic retrograde cholangiopancreatography after 3 months displayed regressive development of the diverse stenoses. Jaundice had disappeared and blood values had returned to normal ranges. Moreover, no tumor of the pancreatic head was present in the magnetic resonance control images. Due to clinical and radiological similarities but a consecutive completely different prognosis and therapy, it is of fundamental importance to differentiate between pancreatic cancer and autoimmune pancreatitis. Especially, determination of serum IgG4 levels and associated bile duct lesions induced by inflammation should clarify the diagnosis of autoimmune pancreatitis and legitimate immunosuppressive therapy

Obeticholic acid for the treatment of non-alcoholic steatohepatitis: interim analysis from a multicentre, randomised, placebo-controlled phase 3 trial

Background Non-alcoholic steatohepatitis (NASH) is a common type of chronic liver disease that can lead to cirrhosis. Obeticholic acid, a farnesoid X receptor agonist, has been shown to improve the histological features of NASH. Here we report results from a planned interim analysis of an ongoing, phase 3 study of obeticholic acid for NASH. Methods In this multicentre, randomised, double-blind, placebo-controlled study, adult patients with definite NASH,non-alcoholic fatty liver disease (NAFLD) activity score of at least 4, and fibrosis stages F2–F3, or F1 with at least oneaccompanying comorbidity, were randomly assigned using an interactive web response system in a 1:1:1 ratio to receive oral placebo, obeticholic acid 10 mg, or obeticholic acid 25 mg daily. Patients were excluded if cirrhosis, other chronic liver disease, elevated alcohol consumption, or confounding conditions were present. The primary endpointsfor the month-18 interim analysis were fibrosis improvement (≥1 stage) with no worsening of NASH, or NASH resolution with no worsening of fibrosis, with the study considered successful if either primary endpoint was met. Primary analyses were done by intention to treat, in patients with fibrosis stage F2–F3 who received at least one dose of treatment and reached, or would have reached, the month 18 visit by the prespecified interim analysis cutoff date. The study also evaluated other histological and biochemical markers of NASH and fibrosis, and safety. This study is ongoing, and registered with ClinicalTrials.gov, NCT02548351, and EudraCT, 20150-025601-6. Findings Between Dec 9, 2015, and Oct 26, 2018, 1968 patients with stage F1–F3 fibrosis were enrolled and received at least one dose of study treatment; 931 patients with stage F2–F3 fibrosis were included in the primary analysis (311 in the placebo group, 312 in the obeticholic acid 10 mg group, and 308 in the obeticholic acid 25 mg group). The fibrosis improvement endpoint was achieved by 37 (12%) patients in the placebo group, 55 (18%) in the obeticholic acid 10 mg group (p=0·045), and 71 (23%) in the obeticholic acid 25 mg group (p=0·0002). The NASH resolution endpoint was not met (25 [8%] patients in the placebo group, 35 [11%] in the obeticholic acid 10 mg group [p=0·18], and 36 [12%] in the obeticholic acid 25 mg group [p=0·13]). In the safety population (1968 patients with fibrosis stages F1–F3), the most common adverse event was pruritus (123 [19%] in the placebo group, 183 [28%] in the obeticholic acid 10 mg group, and 336 [51%] in the obeticholic acid 25 mg group); incidence was generally mild to moderate in severity. The overall safety profile was similar to that in previous studies, and incidence of serious adverse events was similar across treatment groups (75 [11%] patients in the placebo group, 72 [11%] in the obeticholic acid 10 mg group, and 93 [14%] in the obeticholic acid 25 mg group). Interpretation Obeticholic acid 25 mg significantly improved fibrosis and key components of NASH disease activity among patients with NASH. The results from this planned interim analysis show clinically significant histological improvement that is reasonably likely to predict clinical benefit. This study is ongoing to assess clinical outcomes