- Email: [email protected]
Effect of ovariectomy on the proliferative capacity of intrahepatic rat cholangiocytes
Poster Sessions
140
Category 7: Transport, biliary disease, gallstones ~ 0 - ~ PODOPLANIN AND MUCOSAL ADDRESSIN CELL ADHESION MOLECULE-1 (MAdCAM-1) LOCALISATION IN PRIMARY SCLEROSING CHOLANGITIS (PSC) AND PRIMARY BILIARY CIRRHOSIS (PBC) Aftab Ala 1, Richard Standish 2, Korsa Khan 2, Kenneth Hillan 3, Amar Dhillon2, Humphrey Hodgson 1.1 Centrefor Hepatology, The Royal
Free and University College Medical School, Royal Free Campus, London; 2Department of Histopathology, Royal Free and University College Medical School, Royal Free Campus, London, UK; 3Dept of Pathology, Genentech, San Francisco, USA
Background: MAdCAM-1 is pivotal in the emigration of lymphocytes expressing a4b7 cell surface integrin from the circulation into tissues of the gastrointestinal tract. MAdCAM-1 upregulation has been demonstrated in inflammatory diseases of the liver and appears to contribute to the pathogenesis of ductopenic liver disease. We investigated the hypothesis that MadCAM-1 might play a role in lymphocyte trafficking within lymphatic vasculature in these conditions. Podoplanin is a 38-kd membrane glycoproteins of podocytes, reported to be a selective marker of lymphatic endothelium. Aims: We report the nature and distribution of vessels on which MAdCAM-1 is expressed, in cirrhotic ductopenic liver disease Methods: Sections of cirrhotic liver explants from nine patients with PSC and seven with PBC were evaluated were evaluated for expression of MAdCAM- 1 and CD34 using an alkaline phosphatase immunohistochemical technique. Sections of normal liver were used as control. Podoplanin expression was evaluated by using immunoperoxidase methodology. Results: MAdCAM-1 immunoreactivity was not evident in the controls, but present in all cirrhotic sections, localized to septal lymphoid aggregates (either around the aggregate center or in blood vessel endothelium, thought to be high endothelial venule) as weU as the peribiliary capillary plexus (PBP) endothelium (associated with predominantly medium to large bile ducts). Similar staining patterns were seen in both PSC and PBC. Podoplanin was located in vessels with morphological features of lymphatic channels surrounding immediately subjacent to and separate from lymphoid aggregates. These vessels were characterised by a single layer of flattened endothelium without evidence of erythrocytes within their lumen, and were spatially distinct from vessels expressing MAdCAM- 1. Conclusion: MAdCAM-1 expression demonstrated within lymphoid aggregates and in PBP vessels identifies presumptive sites of lymphocyte emigration. We have demonstrated immunoreactive MAdCAM-1 in and around lymphoid aggregates, and Podoplanin immunostaining shows that these vessels are not lymphatic channels. These studies suggest that the expression of MAdCAM-1 on PBP endothelium may contribute to ductopenic liver disease, providing further evidence to support an immune mediated basis to the pathogenesis of PSC and PBC. ~ - 2 - ] THE SIGNAL TRANSDUCTION PATHWAYS BY WHICH ISCHEMIA-REPERFUSION LEADS TO APOPTOSIS INVOLVE TNF-alpha SECRETION, SPHINGOMYELINASE ACTIVATION AND INTIATION OF LIPID PEROXIDATION Alice Alessenko, Lioudmila Dudnik, Elena Mochalova, Mafia Shupik, Eduard Galperin. RAS Institute of biochemical physics, Moscow, Russia Apoptosis of hepatocytes occurs rapily following reperfusion after warm and cold ischemia. Kupffer cells are shown to produce TNF-alpha under a triggering stimulation of apoptosis. To reveal the mechanism of TNF-alpha involvement in the initiation of apoptosis induced in liver cells by ischemia
and reperfusion was analyzed. Changes in the level of TNF-alpha and accumulation of peroxides in lipids, DNA fragmentation, activity of neutral and acidic sphingomyelinase and content of sphingomyelin and ceramides in rat liver after ischemia and followed reperfusion have been studied. Wistar rats were subjected to (15, 30 min; 1 and 2 hrs) of total liver ischemia and followed reperfusion (from 15 min to 2 hrs). Ischemia induced abrupt declines in neutral and acidic sphingomyelinase activity. But activities of both enzymes are dramatically increased after reperfusion. Small amount of TNF-alpha detected by immuno blot analysis is accumulated in ischemic area of liver rapidly and this cytokine is dramatically increased after reperfusion. We found that accumulation of TNF-alpha and increase of sphingomyelinase activity during the induction of ischemic/reperfusion injury coincided with increase of lipid peroxidation and DNA degradation detected by gel electrophoresis. We suppose that cross-talk between oxidation system and sphingomyelin cycle exists in cells and could have important implication for the induction phase and evolution of post-ischemic
injury. ~ 0 - ~ EFFECT OF OVARIECTOMY ON THE PROLIFERATIVE CAPACITY OF INTRAHEPATIC RAT CHOLANGIOCYTES Domenico Alvaro l, Gianfranco Alpini3, Paolo Onori2, Antonio Franchitto2, Shannon Glaser 3, Gene Le Sage 3, Alessandro Gigliozzi 1, Adolfo Attili 1, Eugenio Gaudio. 1Department of
Clinical Medicine Division of Gastroenterology University of Rome La Sapienza, ROME; 2Department of Anatomy University of Rome La Sapienza, ROME, Italy; 32Dept. of lnternal Medicine, 3Medical Physiology, Scott & White Hospital and The TexasA&M University System HSC, COM and Central Texas VeteransHealth Care System, Temple, Texas, USA We evaluated the effects of ovariectomy (OVX) and estrogen replacement treatment on cholangiocyte proliferation induced by bile duct ligation (BDL). Methods: BDL was performed for two weeks in OVX rats and the proliferative and apoptotic activity, evaluated by immunohistochemistry and western-blot, was compared with normal, BDL control rats and with BDL plus OVX rats treated with beta-estradiol. Results: OVX induced a significant reduction of bile duct mass in BDL rats. The reduction of bile duct mass induced by OVX was associated with a decreased expression of estrogen receptor alpha (three fold) and mainly estrogen receptor beta (thirty fold). PCNA expression (immunohistochemistry and western-blot) in cholangiocytes was impaired by OVX, indicating depression of proliferation, whereas TUNEL and Fas positivity were markedly enhanced indicating activation of Fas mediated apoptosis. Administration of beta-estradiol during BDL in OVX rats induced a normalization of bile duct mass, ER expression, cholangiocyte proliferation (PCNA) and apoptosis (Fas and TUNEL) in comparison with untreated BDL rats. Conclusions: Our findings support the role of endogenous estrogens in sustaining the enhanced proliferative and secretory activities of cholangiocyte in cholestasis. On the basis of these data, the hypothesis of an estrogenic functional deficiency in chronic cholestatic liver diseases should merit careful attention.
[-~
REEMPTIVE ANALGESIA WITH LOW-DOSE OF KETAMINE IN GALLSTONE SURGERY: A RANDOMIZED STUDY
Oana Chelarescu 1, Dan Chelarescu 2, Eugen Tircoveanu l, Iulian Stratan 1.
1University of Medicine and Pharmacy 'Gr. T. Popa' lasL Anesthesiology Department; 2University of Medicine and Pharmacy 'Gr. T Popa' lasi, Pharmacology Department, Background/Aim: Preemptive analgesia switch off the central sensitization process which is the result of visceral lesions. In upper abdominal surgery, multiple blockades of pain impulses are necessary for definitive
140
Category 7: Transport, biliary disease, gallstones ~ 0 - ~ PODOPLANIN AND MUCOSAL ADDRESSIN CELL ADHESION MOLECULE-1 (MAdCAM-1) LOCALISATION IN PRIMARY SCLEROSING CHOLANGITIS (PSC) AND PRIMARY BILIARY CIRRHOSIS (PBC) Aftab Ala 1, Richard Standish 2, Korsa Khan 2, Kenneth Hillan 3, Amar Dhillon2, Humphrey Hodgson 1.1 Centrefor Hepatology, The Royal
Free and University College Medical School, Royal Free Campus, London; 2Department of Histopathology, Royal Free and University College Medical School, Royal Free Campus, London, UK; 3Dept of Pathology, Genentech, San Francisco, USA
Background: MAdCAM-1 is pivotal in the emigration of lymphocytes expressing a4b7 cell surface integrin from the circulation into tissues of the gastrointestinal tract. MAdCAM-1 upregulation has been demonstrated in inflammatory diseases of the liver and appears to contribute to the pathogenesis of ductopenic liver disease. We investigated the hypothesis that MadCAM-1 might play a role in lymphocyte trafficking within lymphatic vasculature in these conditions. Podoplanin is a 38-kd membrane glycoproteins of podocytes, reported to be a selective marker of lymphatic endothelium. Aims: We report the nature and distribution of vessels on which MAdCAM-1 is expressed, in cirrhotic ductopenic liver disease Methods: Sections of cirrhotic liver explants from nine patients with PSC and seven with PBC were evaluated were evaluated for expression of MAdCAM- 1 and CD34 using an alkaline phosphatase immunohistochemical technique. Sections of normal liver were used as control. Podoplanin expression was evaluated by using immunoperoxidase methodology. Results: MAdCAM-1 immunoreactivity was not evident in the controls, but present in all cirrhotic sections, localized to septal lymphoid aggregates (either around the aggregate center or in blood vessel endothelium, thought to be high endothelial venule) as weU as the peribiliary capillary plexus (PBP) endothelium (associated with predominantly medium to large bile ducts). Similar staining patterns were seen in both PSC and PBC. Podoplanin was located in vessels with morphological features of lymphatic channels surrounding immediately subjacent to and separate from lymphoid aggregates. These vessels were characterised by a single layer of flattened endothelium without evidence of erythrocytes within their lumen, and were spatially distinct from vessels expressing MAdCAM- 1. Conclusion: MAdCAM-1 expression demonstrated within lymphoid aggregates and in PBP vessels identifies presumptive sites of lymphocyte emigration. We have demonstrated immunoreactive MAdCAM-1 in and around lymphoid aggregates, and Podoplanin immunostaining shows that these vessels are not lymphatic channels. These studies suggest that the expression of MAdCAM-1 on PBP endothelium may contribute to ductopenic liver disease, providing further evidence to support an immune mediated basis to the pathogenesis of PSC and PBC. ~ - 2 - ] THE SIGNAL TRANSDUCTION PATHWAYS BY WHICH ISCHEMIA-REPERFUSION LEADS TO APOPTOSIS INVOLVE TNF-alpha SECRETION, SPHINGOMYELINASE ACTIVATION AND INTIATION OF LIPID PEROXIDATION Alice Alessenko, Lioudmila Dudnik, Elena Mochalova, Mafia Shupik, Eduard Galperin. RAS Institute of biochemical physics, Moscow, Russia Apoptosis of hepatocytes occurs rapily following reperfusion after warm and cold ischemia. Kupffer cells are shown to produce TNF-alpha under a triggering stimulation of apoptosis. To reveal the mechanism of TNF-alpha involvement in the initiation of apoptosis induced in liver cells by ischemia
and reperfusion was analyzed. Changes in the level of TNF-alpha and accumulation of peroxides in lipids, DNA fragmentation, activity of neutral and acidic sphingomyelinase and content of sphingomyelin and ceramides in rat liver after ischemia and followed reperfusion have been studied. Wistar rats were subjected to (15, 30 min; 1 and 2 hrs) of total liver ischemia and followed reperfusion (from 15 min to 2 hrs). Ischemia induced abrupt declines in neutral and acidic sphingomyelinase activity. But activities of both enzymes are dramatically increased after reperfusion. Small amount of TNF-alpha detected by immuno blot analysis is accumulated in ischemic area of liver rapidly and this cytokine is dramatically increased after reperfusion. We found that accumulation of TNF-alpha and increase of sphingomyelinase activity during the induction of ischemic/reperfusion injury coincided with increase of lipid peroxidation and DNA degradation detected by gel electrophoresis. We suppose that cross-talk between oxidation system and sphingomyelin cycle exists in cells and could have important implication for the induction phase and evolution of post-ischemic
injury. ~ 0 - ~ EFFECT OF OVARIECTOMY ON THE PROLIFERATIVE CAPACITY OF INTRAHEPATIC RAT CHOLANGIOCYTES Domenico Alvaro l, Gianfranco Alpini3, Paolo Onori2, Antonio Franchitto2, Shannon Glaser 3, Gene Le Sage 3, Alessandro Gigliozzi 1, Adolfo Attili 1, Eugenio Gaudio. 1Department of
Clinical Medicine Division of Gastroenterology University of Rome La Sapienza, ROME; 2Department of Anatomy University of Rome La Sapienza, ROME, Italy; 32Dept. of lnternal Medicine, 3Medical Physiology, Scott & White Hospital and The TexasA&M University System HSC, COM and Central Texas VeteransHealth Care System, Temple, Texas, USA We evaluated the effects of ovariectomy (OVX) and estrogen replacement treatment on cholangiocyte proliferation induced by bile duct ligation (BDL). Methods: BDL was performed for two weeks in OVX rats and the proliferative and apoptotic activity, evaluated by immunohistochemistry and western-blot, was compared with normal, BDL control rats and with BDL plus OVX rats treated with beta-estradiol. Results: OVX induced a significant reduction of bile duct mass in BDL rats. The reduction of bile duct mass induced by OVX was associated with a decreased expression of estrogen receptor alpha (three fold) and mainly estrogen receptor beta (thirty fold). PCNA expression (immunohistochemistry and western-blot) in cholangiocytes was impaired by OVX, indicating depression of proliferation, whereas TUNEL and Fas positivity were markedly enhanced indicating activation of Fas mediated apoptosis. Administration of beta-estradiol during BDL in OVX rats induced a normalization of bile duct mass, ER expression, cholangiocyte proliferation (PCNA) and apoptosis (Fas and TUNEL) in comparison with untreated BDL rats. Conclusions: Our findings support the role of endogenous estrogens in sustaining the enhanced proliferative and secretory activities of cholangiocyte in cholestasis. On the basis of these data, the hypothesis of an estrogenic functional deficiency in chronic cholestatic liver diseases should merit careful attention.
[-~
REEMPTIVE ANALGESIA WITH LOW-DOSE OF KETAMINE IN GALLSTONE SURGERY: A RANDOMIZED STUDY
Oana Chelarescu 1, Dan Chelarescu 2, Eugen Tircoveanu l, Iulian Stratan 1.
1University of Medicine and Pharmacy 'Gr. T. Popa' lasL Anesthesiology Department; 2University of Medicine and Pharmacy 'Gr. T Popa' lasi, Pharmacology Department, Background/Aim: Preemptive analgesia switch off the central sensitization process which is the result of visceral lesions. In upper abdominal surgery, multiple blockades of pain impulses are necessary for definitive