TY - JOUR
T1 - Apoptosis and dysregulated ceramide metabolism in a murine model of alcohol-enhanced lipopolysaccharide hepatotoxicity
AU - Deaciuc, Ion V.
AU - Nikolova-Karakashian, Mariana
AU - Fortunato, Franco
AU - Lee, E. Y.
AU - Hill, Daniell B.
AU - McClain, Craig J.
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2000
Y1 - 2000
N2 - Background: The role of apoptosis in EtOH-induced liver injury has not been investigated much. Therefore, the question whether apoptosis is a contributory factor to alcoholic liver disease remains to be answered. The purpose of this study was to characterize the liver apoptotic response in a murine model of alcohol-enhanced lipopolysaccharide (LPS) hepatotoxicity. Methods: Mice were fed an alcohol-containing liquid diet for 49 days followed by an acute LPS challenge. The liver state was judged on the basis of histological appearance, plasma liver enzyme activity (alanine:2-oxoglutarate and aspartate:2-oxoglutarate aminotransferases, as markers of hepatocytolysis), and plasma hyaluronan levels (as a marker of the sinusoidal endothelial cell scavenging function). The liver apoptotic response was assessed by DNA fragmentation (TUNEL procedure), and caspases-3 and -8 activity. To determine if ceramide played a role in the liver apoptotic response, the activity of acidic sphingomyelinase and tissue content of ceramide were also quantified. Results: Alcohol exposure induced fat accumulation and sensitized the liver to LPS injurious effects. Plasma liver enzyme activity was elevated by alcohol and this effect was potentiated by LPS. Liver apoptosis was augmented by both alcohol and LPS treatment as reflected by high frequency of positive TUNEL staining nuclei and by an increased activity of caspase-3 and -8. Acidic sphingomyelinase activity was also increased and it was associated with an elevated tissue content of ceramide. In addition, LPS also increased plasma TNF-α levels. These changes were accompanied by elevated plasma hyaluronan, reflecting an impaired sinusoidal endothelial cell scavenging function. Conclusions: These results provide a more complete description of the liver apoptotic response to both alcohol and LPS and may constitute the basis for further mechanistic studies on a possible role apoptosis may play in alcoholic liver injury.
AB - Background: The role of apoptosis in EtOH-induced liver injury has not been investigated much. Therefore, the question whether apoptosis is a contributory factor to alcoholic liver disease remains to be answered. The purpose of this study was to characterize the liver apoptotic response in a murine model of alcohol-enhanced lipopolysaccharide (LPS) hepatotoxicity. Methods: Mice were fed an alcohol-containing liquid diet for 49 days followed by an acute LPS challenge. The liver state was judged on the basis of histological appearance, plasma liver enzyme activity (alanine:2-oxoglutarate and aspartate:2-oxoglutarate aminotransferases, as markers of hepatocytolysis), and plasma hyaluronan levels (as a marker of the sinusoidal endothelial cell scavenging function). The liver apoptotic response was assessed by DNA fragmentation (TUNEL procedure), and caspases-3 and -8 activity. To determine if ceramide played a role in the liver apoptotic response, the activity of acidic sphingomyelinase and tissue content of ceramide were also quantified. Results: Alcohol exposure induced fat accumulation and sensitized the liver to LPS injurious effects. Plasma liver enzyme activity was elevated by alcohol and this effect was potentiated by LPS. Liver apoptosis was augmented by both alcohol and LPS treatment as reflected by high frequency of positive TUNEL staining nuclei and by an increased activity of caspase-3 and -8. Acidic sphingomyelinase activity was also increased and it was associated with an elevated tissue content of ceramide. In addition, LPS also increased plasma TNF-α levels. These changes were accompanied by elevated plasma hyaluronan, reflecting an impaired sinusoidal endothelial cell scavenging function. Conclusions: These results provide a more complete description of the liver apoptotic response to both alcohol and LPS and may constitute the basis for further mechanistic studies on a possible role apoptosis may play in alcoholic liver injury.
KW - Caspase
KW - Liver Ceramide
KW - Liver TUNEL Response
KW - Plasma Hyaluronan
KW - Sphingomyelinase
UR - http://www.scopus.com/inward/record.url?scp=0033772936&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033772936&partnerID=8YFLogxK
U2 - 10.1097/00000374-200010000-00014
DO - 10.1097/00000374-200010000-00014
M3 - Article
C2 - 11045865
AN - SCOPUS:0033772936
SN - 0145-6008
VL - 24
SP - 1557
EP - 1565
JO - Alcoholism: Clinical and Experimental Research
JF - Alcoholism: Clinical and Experimental Research
IS - 10
ER -