POSTERS Methods: Total RNA was isolated from livers harvested between 3 and 72 h following 70% PH or sham operations, from both 0.4% (wt/wt) UDCA and control diet-fed animals. miRNA expression profiles were determined using a custom microarray platform; and real time RT-PCR analysis of selected miRNAs was used for validation. miRNA-21 expression was further evaluated in isolated primary rat hepatocytes and HepG2 cells, following incubation with UDCA. Results: The results showed that several miRNAs were significantly altered after PH by >1.5-fold, including some previously described as modulators of cell proliferation, differentiation, and death. UDCA feeding appears to shift miRNA expression patterns toward those observed after PH in sham-operated animals. Expression of miRNA21 was increased after PH, in both UDCA and control diet-fed animals. In addition, UDCA modulated miRNA-21 expression in HepG2 cells. Conclusions: miRNAs, in particular miRNA-21, may play a significant role in modulating proliferation and cell cycle progression genes after PH. miRNA-21 is additionally induced by UDCA in both regenerating rat liver and HepG2 cells, which may represent a new mechanism behind UDCA biological functions. Supported by grants PTDC/SAU-FCF/67912/2006 and PTDC/BIABCM/67922/2006 from FCT, Portugal. 931 HEPATIC MITOCHONDRIA OBTAINED FROM 6-OHDA-LESIONED PARKINSONIAN RATS EXHIBIT DECREASED ENERGY CAPACITY AND MEMBRANE POTENTIAL M. Vairetti1 , A. Ferrigno1 , V. Rizzo2 , G. Ambrosi3 , A. Bianchi1 , P. Richelmi1 , F. Blandini3 , M.T. Armentero3 . 1 Internal Medicine and Therapeutics, 2 Biochemistry, IRCCS San Matteo, University of Pavia, 3 Interdepartmental Research Center for Parkinson’s Disease – Lab. Functional Neurochemistry, IRCCS Neurological Institute C. Mondino, Pavia, Italy E-mail:
[email protected] Background and Aim: The autonomic nervous system influences organ functions. The liver, in particular, is directly innervated and regulated by autonomic nerves. Parkinson’s disease (PD) is classically characterized by motor symptoms and autonomic disorders and is linked to mitochondrial dysfunction. In this study we investigated hepatic mitochondrial function in a classic rodent model of PD based on nigrostriatal degeneration induced by 6-hydroxydopamine (6-OHDA). Materials and Methods: Male Sprague-Dawley rats received a unilateral intrastriatal injection of 6-OHDA or vehicle (sham), and were sacrificed after 24-hours, 4 or 8 weeks. Nigrostriatal degeneration was evaluated in the striatum and substantia nigra pars compacta (SNpc). ATP content/production (luciferinluciferase method), and membrane potential (rhodamine123) were determined in hepatic mitochondria, while expression of the dopamine transporter (DAT) – required for 6-OHDA toxicity – was assessed in liver extracts. Plasma levels of transaminases and 6-OHDA were measured; selected cytokines were measured in plasma and cerebrospinal fluid. The effects of 6-OHDA (12.5–200 mM) on cellular vitality and mitochondrial ATP production were also tested in isolated hepatocytes. Results: The 6-OHDA-induced nigrostriatal lesion peaked in the striatum and SNpc (84.4% and 68.9%, respectively) after four weeks, remaining substantially unmodified thereafter. Liver mitochondria obtained 4 and 8 weeks after 6-OHDA injection exhibited decreased ATP content/production compared to sham animals; membrane potential was significantly reduced after 8 weeks, while no mitochondrial alterations were observed 24-hours after the toxic insult. Hepatocyte suspensions exposed to 6-OHDA exhibited normal ATP values and no dose-dependent toxicity. DAT expression was absent in liver extracts and 6-OHDA was never detected in
plasma. No changes in cytokine and transaminase levels were found in animals bearing the nigrostriatal lesion. Conclusions: Our study clearly shows that, in a rodent model of PD, nigrostriatal degeneration is associated with hepatic mitochondria dysfunction. These alterations were not caused by systemic diffusion of 6-OHDA to peripheral compartments or activation of inflammatory processes. Nigrostriatal degeneration in PD is associated with alterations of the autonomic nervous system that account for many non-motor symptoms of the disease; these alterations may also influence the hepatic energy capacity through mechanisms that will have to be clarified in future studies. 932 THE THERAPEUTIC EFFECT OF LOW MOLECULAR WEIGHT HEPARIN ON CCL4 -INDUCED NECROSIS AND APOPTOSIS IN RAT LIVER A. Kukner1 , F. Tore2 , T. Firat1 , E.H. Terzi1 , H. Oner3 , Y. Balaban4 , C. Ozogul5 . 1 Histology and Embryology, Abant Izzet Baysal University, Faculty of Medicine, 2 Physiology, Abant Izzet Baysal University, Bolu, 3 Histology and Embryology, Mehmet Akif University, Faculty of Veterinary Medicine, Burdur, 4 Gastroenterology, Hacettepe University, Faculty of Medicine, 5 Histology and Embryology, Gazi University, Faculty of Medicine, Ankara, Turkey E-mail:
[email protected] Background and Aims: Regardless of its etiology, liver injury results in liver failure, cirrhosis, portal hypertension, or hepatocellular carcinoma. Heparin having anti-inflammatory and anti-fibrotic properties may have therapeutic effect on liver injury. The present study investigated the effect of low molecular weight heparin (enoxaparin) on CCL4 -induced hepatic necrosis and apoptosis in rats. Methods: Twenty five male rats were divided into 5 groups. Group I: control group. Group II: Olive oil dissolved CCl4 at dose of 1ml/kg, ip, twice per week. Group III: CCl4 + enoxaparin at dose of 180 IU/kg, sc, daily. Group IV: Enoxaparin group. Group V: Olive oil at dose of 1 ml, ip, twice per week. The liver histology at the forth week was examinated by haematoxylin-eosin, Masson’s trichrome and Periodic acid schiff stains. Proliferative and apoptotic activities were assessed semi-quantitatively by proliferating cell nuclear antigen (PCNA) and caspase-3 immune staining and TUNEL method. Semi-quantitative values formulated Pi(i+1) including both distribution by the equation HSCORE = and intensity of staining. Additionally, insuline-like growth factor 1 (IGF-I), nidogen and a-smooth muscle actin were labeled by immunohistochemistry. Results: CCl4 group had marked hepatocelluar necrosis around the vena centralis and increased inflammatory cells. Hepatocytes showed lipid droplets, decrease in glycogen, apoptosis, and picnotic or enlarged nuclei. Enoxaparin decreased the necrosis and apoptosis, but have no effect on lipid droplets in hepatocytes. HSCORE’s of caspase-3, PCNA, IGF-I were also significantly decreased by enoxaparin administration. Conclusions: Enoxaparin may have beneficial effect on necrosis as well as apoptosis at the early stage of CCL4 induced liver injury. 933 MICRORNA-221 TARGETS PUMA AND SENSITIZES HUMAN HEPATOCELLULAR CARCINOMA CELLS TO DOXORUBICIN TREATMENT F. Fornari1 , L. Gramantieri1 , M. Milazzo1 , D. Pollutri1 , G.L. Grazi1 , M. Negrini2 , L. Bolondi1 . 1 University of Bologna, Bologna, 2 University of Ferrara, Ferrara, Italy E-mail:
[email protected] Background and Aims: MicroRNAs (miRNAs) are aberrantly expressed in human cancers and recent evidences support their potential use in cancer treatment. We previously reported that
Journal of Hepatology 2010 vol. 52 | S319–S457
S361
