ORAL PRESENTATIONS 16 IDENTIFICATION OF THE HENLE’S LOOP AS A MAJOR SITE OF SODIUM RETENTION IN EXPERIMENTAL PREASCITIC CIRRHOSIS: EFFECTS OF PARATHYROID HORMONE G. Sansoe1 , M. Aragno2 , E. Novo2 , R. Mastrocola2 , M. Parola2 . 1 Division of Gastroenterology, Gradenigo Hospital, 2 Dpt. of Experimental Medicine and Oncology, University of Torino, Torino, Italy E-mail:
[email protected] Extracellular Ca++ stimulates membrane-bound calcium-sensing receptors (CaRs). In turn, CaRs stimulation leads to PGE2 -mediated decrease in protein content of Na+ -K+ -2Cl− co-transporters (BSC-1) in the thick ascending limb (TAL) of Henle’s loop and of aquaporin 2 (AQP2) water channels in collecting ducts. Parathyroid hormone (PTH) increases CaRs expression and, consequently, decreases BSC-1 and AQP2 content. To assess this Ca++ -dependent diuretic system in preascitic cirrhosis we evaluated renal function, hormonal status, PGE2 urinary excretion, renal content of BSC-1 and CaRs in three groups of rats: one group of controls receiving s.c. 5% glucose solution and two groups of rats with CCl4 -induced preascitic cirrhosis receiving either glucose solution or five s.c. doses of 10 mcg/kg PTH (one dose every 12 h) prior to study. The amount of fluid administered to each group was the same. Compared to controls, cirrhotic rats showed reduced urine volume and sodium excretion (P < 0.05); western blot analysis revealed reduced CaRs and increased BSC-1 protein content in cirrhotic rat kidneys (all P < 0.01). PTH-treated cirrhotic rats had urine and sodium excretion normalized; s.c. PTH increased also renal plasma flow, PGE2 urinary excretion, free-water clearance, reduced BSC-1 and augmented CaRs content in cirrhotic rat kidneys (all P < 0.01 v. untreated cirrhosis). In conclusion, in preascitic cirrhosis sodium retention is linked to downregulation of renal CaRs and upregulation of tubular Na+ -K+ -2Cl− co-transporters. PTH returns these biomolecular alterations and sodium and urine excretions to normality. Therefore, exaggerated sodium reabsorption in Henle’s loop is largely responsible for sodium retention in preascitic cirrhosis. 17 RENAL FAILURE IN CIRRHOSIS: PROGNOSTIC VALUE OF THE AETIOLOGY OF RENAL FAILURE. A PROSPECTIVE STUDY OF 562 PATIENTS M. Martin Llah´ı1,2,3 , M. Guevara1,2,3 , C. Fagundes1,2,3 , A. Torre1 , M. Marinelli1,2 , T. Restuccia1 , G. Pereira1,2 , M. Pavesi1,3 , E. Sola1,2,3 , V. Arroyo1,2,3 , P. Gines ` 1,2,3 . 1 Liver Unit, Hospital Cl´ınic, Universidad de 2 3 Barcelona, Idibaps, CIBERHED (Ciber de Enfermedades Hep´ aticas y Digestivas), Barcelona, Spain E-mail:
[email protected] Renal failure is a common complication of cirrhosis. The prognosis of patients with cirrhosis and renal failure is poor. However, whether the aetiology of renal failure has prognostic implications is not well known. With this aim 562 consecutive patients with cirrhosis and renal failure admitted to our Unit during a period of 6 years were prospectively evaluated. Survival was assessed at 3 months. The aetiologies of renal failure were: bacterial infections (n = 212), hypovolemia (n = 154), hepatorenal syndrome without infection (n = 60), parenchymal renal diseases (n = 42), nephrotoxicity (n = 20), and more than one aetiologic factor (n = 74). Renal failure due to bacterial infections and hepatorenal syndrome were analyzed as a single group because they share a similar pathogenic mechanism. Patients with nephrotoxicity or more than one cause of renal failure were excluded from the analysis. Patients with hepatorenal syndrome with or without infection had a 3-month survival significantly lower compared to that of the other groups (hepatorenal syndrome: 24% vs hypovolemia: 44% and parenchymal renal diseases: 73%, p < 0.001 for both). A logistic regression model was fitted to assess whether the aetiology of renal S8
failure was independently associated with mortality. The estimated effect of aetioloy (hepatorenal syndrome with and without infection vs the other groups) on 3-month mortality was significant (OR: 1.61;95% CI: 1.01–2.56; p = 0.045) even after adjusting for the strongest confounders: MELD (OR: 1.14; 95% CI: 1.1–1.19) and serum sodium (OR: 0.96; 95% CI: 0.92–0.99). In conclusion, the results of this study suggest that in patients with cirrhosis and renal failure, the aetiology of renal failure adds prognostic value to the MELD score and serum sodium, hepatorenal syndrome having a worst prognosis compared to that of other causes of renal failure. These results might have implications in the evaluation of the severity of cirrhosis in patients with renal failure awaiting liver transplantation. 18 BETA-2-ADRENERGIC RECEPTOR FUNCTION IS DIFFERENT ACCORDING TO PROPRANOLOL RESPONSE AND POLYMORPHISMS PRESENCE IN PORTAL HYPERTENSION CIRRHOTIC PATIENTS 2 3 A.M. Peiro´ 1 , L. Gomez-Escolar ´ , P. Zapater1 , P. Gimenez ´ , J.M. Palazon ´ 2 . 1 Clinical Pharmacology Division. Hospital General de Alicante, 2 Liver Unit, Hospital General de Alicante, Alicante, 3 CIBERehd, Instituto de Salud Carlos III, Madrid, Spain E-mail:
[email protected] Background: The high interindividual variability of cirrhotic portal hypertension patients (PH) in the response to propranolol prophylactic treatment of gastrointestinal bleeding could be associated to the presence of beta-2-adrenergic receptor (ADRB2) polymorphisms and/or an impaired ADRB2 functionality. Our aim is to study simultaneously both topics in this population. Methods: A total of consecutive 52 PH cirrhotic patients (mean age= 53 years; sex (M/F) 45/7; cirrhosis etiology: 42% virus, 27% alcohol, 23% virus plus alcohol and 8% others; CHILD 7±2 (mean±DE); MELD 11±4 and mean hepatic venous pressure gradient (HVPG) 13±4 mmHg) were included. Patients were classified according to the prophylaxis type and response to propanolol: primary (PH-P) (n = 22; responder = 12; non-responder = 10) or secondary (PH-S) (n = 30; responder = 9; non-responder = 21) prophylaxis. A control group of 22 healthy subjects was included. Lymphocyte cAMP production under isoproterenol (ISO, from 10−8 to10−3 ) stimulus and allelic forms of ADRB2 gene (16, 27 and 164 amino acids) were determinate in a blood sample obtained days after HVPG study.
Figure 1. Results: The response of ADRB2 to isoproterenol stimulus (ISO 10−5 concentration) was significantly decreased in PH patients (cAMP mean values were 19, 15 and 105 pmol/mL for PH-S, PH-P and control, respectively) (p < 0.05) and not significant differences
Journal of Hepatology 2010 vol. 52 | S1–S21
ORAL PRESENTATIONS were observed between PH-S and PH-P. According to response to propranolol prophylaxis status, and ADRB2 polymorphisms (SNP) a significant higher ADRB2 activity was observed in non-responder PH patients. This activity was more pronounced when any of the ADRB2 SNP was present in both, responder and non-responder patients (Fig. 1). Conclusions: Non-responder PH patients to propranolol prophylaxis show a most reactive ADRB2 to adrenergic stimulus compared with responders, in both groups, native or polymorphic patients. 19 DARK CHOCOLATE ATTENUATES THE POST-PRANDIAL INCREASE IN HVPG IN PATIENTS WITH CIRRHOSIS AND PORTAL HYPERTENSION A. De Gottardi1,2 , A. Berzigotti1,3,4 , S. Seijo1 , M. D’Amico1 , J. Abraldes1,4 , J.C. Garcia-Pagan ´ 1,4 , J. Bosch1,4 . 1 Hemodynamic Laboratory, Liver Unit and Institut d’Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain; 2 University Clinic of Visceral Surgery and Medicine, Inselspital, Bern, Switzerland; 3 Centre de Diagnostic per l’Imatge, Hospital Clinic de Barcelona, 4 Centro de Investigaci´ on Biom´edica en Red de Enfermedades Hep´ aticas y Digestivas (CIBERehd), University of Barcelona, Barcelona, Spain E-mail:
[email protected] Background and Aim: Dark chocolate holds verified potent antioxidant properties mediated by its high content in cocoa flavonoids. In cirrhosis, the intrahepatic circulation exhibits endothelial dysfunction which is promoted among others by oxidative stress and reduced antioxidant systems. Intrahepatic endothelial dysfunction has been studied in patients by evaluating the post-prandial increase in hepatic venous pressure gradient (HVPG). We hypothesized that dark chocolate might improve intrahepatic endothelial dysfunction in cirrhosis, and designed this study to evaluate whether this nutrient may attenuate the postprandial increase of HVPG in portal hypertensive cirrhotic patients. Patients and Methods: Twenty-one cirrhotic patients with esophageal varices (Child score 6.9±1.8; MELD 11±4; HVPG 16.6±3.8 mmHg) were randomized to receive a standard liquid meal containing either dark chocolate (active treatment, containing 85% cocoa, 0.55 g of dark chocolate/kg of body weight; n = 10) or white chocolate (devoid of cocoa flavonoids; control, n = 11) in a isocaloric composition according to the body weight. HVPG, arterial pressure and portal blood flow (PBF) by US-Doppler were measured at baseline and 30 minutes after meal administration. Results: Both test meals caused a highly significant but similar increase in portal blood flow (median increase in PBF: +24% in dark chocolate Vs +34% in white chocolate, NS). Post-prandial hyperemia was accompanied by an increase in HVPG: dark chocolate from 17.3±3.6 mmHg to 19.1±2.6 mmHg (p = 0.07); white chocolate from 16.0±4.7 mmHg to 19.7±4.1 mmHg (p = 0.003). The post-prandial increase in HVPG was markedly attenuated in patients receiving dark chocolate (+10.3±16.3% Vs +26.3±12.7%, p = 0.02). Moreover, dark chocolate patients, but not white chocolate ones, showed a significant post-prandial increase in mean arterial pressure (+9.9±8.4% vs. −0.3±4.9%, p = 0.003). Conclusions: In patients with cirrhosis a test meal containing dark chocolate blunted the post-prandial increase in HVPG without changing post-prandial hyperemia, suggesting that it acted by attenuating hepatic endothelial dysfunction so allowing intrahepatic vasorelaxation in response to the post-prandial increase in portal blood flow. Dark chocolate also increased mean arterial pressure, indicating that it also exerted beneficial systemic effects. This study suggests that adding dark chocolate to meals may attenuate the brisk post-prandial increase in portal pressure observed in portal hypertensive cirrhotic patients.
20 PPARa ACTIVATION REDUCES PORTAL PRESSURE AND AMELIORATES ENDOTHELIAL DYSFUNCTION IN CIRRHOSIS A. Rodriguez-Vilarrupla, B. Lavina, H. Garc´ıa-Caldero, ´ L. Russo, ´ Hepatic Hemodynamic M. Fernandez, ´ J. Bosch, J.C. Garc´ıa-Pagan. Lab, Hospital Cl´ınic i Provincial, CIBEREHD, IDIBAPS, Barcelona, Spain E-mail:
[email protected] Background and Aims: PPARa is a transcription factor activated by ligands belonging to the family of nuclear receptors. Its transcriptional program includes among others, genes involved in the regulation of vascular tone, oxidative stress and fibrogenesis, pathways implicated in the development of cirrhosis and portal hypertension. Therefore, modulation of PPARa could have beneficial effects in portal hypertension. This study is aimed at evaluating the effects of PPARa activation with fenofibrate on hepatic and systemic hemodynamics, hepatic endothelial dysfunction and hepatic fibrosis in CCl4 cirrhotic rats (CH). Methods: CH rats were treated with fenofibrate (FF, 25 mg/kg/day, n = 8) or their vehicle (n = 10) orally for 7 days; then the following measurements were done: a. in vivo mean arterial pressure (MAP), portal pressure (PP), portal blood flow (PBF); b. in isolated perfused livers endothelial function was assessed by dose-relaxation curves to acetylcholine; c. degree of fibrosis in liver sections stained with Sirius Red and Masson trichrome, and d. activation of hepatic stellate cells, assessed by protein expression of a-smooth muscle actin [aSMA] and PDGFRb, and gene expression of TIMP-1, collagen-1, collagen-3, MMP9 and TGFb. Results: The activation of PPARa with FF in CH rats: a) significantly decreased PP (17.1±0.78 mmHg vs 12.2±0.6 mmHg) and PBF (1.7±0.3 ml/min−1 ·g−1 vs 0.9±0.1 ml/min−1 ·g−1 ), and significantly increased MAP (82.5±4.8 mmHg vs 103±7 mmHg); b) improved the endothelium-dependent response to acetylcholine; c) reduced fibrosis as evidenced by morphometric analysis on liver sections stained with Sirius Red and Masson’s trichrome, and d) decreased the protein expression of aSMA and PDGRFb, The only downregulated gene was collagen-1 mRNA expression. Conclusions: Activation of PPARa with FF has marked beneficial effects in cirrhotic rats, decreasing hepatic stellate cell activation and liver fibrosis, ameliorating hepatic endothelial dysfunction and reducing portal pressure, suggesting that modulation of PPARa may represent a new therapeutic target in the treatment of portal hypertension in cirrhosis. 21 FUNCTIONAL RELEVANT TELOMERASE MUTATIONS ASSOCIATE WITH CIRRHOSIS FORMATION IN PATIENTS WITH CHRONIC LIVER DISEASE D. Hartmann1,2 , U. Srivastava1 , M. Thaler1,3 , K. Kleinhans1 , R. Kratzer1 , K. Bauer1 , S.-F. Katz1 , Y. Begus-Nahrmann1 , G. von 1 Figura1,3 , A. Lechel1 , C. Gunes ¨ , G. N’Kontchou4 , A. Potthoff5 , K. Deterding5 , H. Wedemeyer5 , H. Schrezenmeier6 , M.P. Manns5 , M. Beaugrand4 , K.L. Rudolph1 . 1 Institute of Molecular Medicine and Max-Planck Research Department on Stem Cell Aging, University of Ulm, Ulm, 2 Department of Surgery, Technical University Munich, Munich, 3 Department of Internal Medicine I, University of Ulm, Ulm, Germany; 4 Liver Unit, Hˆ opital Jean Verdier, Bondy, France; 5 Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, 6 Institute for Clinical Transfusion Medicine and Immunogenetics, University of Ulm, Ulm, Germany E-mail:
[email protected] Background and Aims: Telomere shortening is associated with the evolution of cirrhosis in the end-stage of chronic liver disease. Genetic findings have proven that mutations in the enzyme telomerase are the underlying cause of accelerated telomere
Journal of Hepatology 2010 vol. 52 | S1–S21
S9
