Anti-oxidants do not prevent bile acid-induced cell death in rat hepatocytes.
BACKGROUND
Bile acids, reactive oxygen species (ROS) and inflammatory cytokines are crucial regulators of cell death in acute and chronic liver diseases. The contribution of each factor to hepatocyte death, either apoptosis or necrosis, has not been clarified as yet. It has been suggested that the generation of oxidative stress by bile acids contributes to hepatocyte death during cholestasis and bile acid toxicity, although the beneficial role of ROS prevention in bile acid-mediated cell death is not fully understood.


OBJECTIVE
Study the effects of anti-oxidants in bile acid-induced cell death in vitro.


METHODS
Primary rat hepatocytes were exposed to the bile acids glycochenodeoxycholic acid (GCDCA) or taurolithocholic acid-3 sulphate in the absence or presence of ROS scavengers or anti-oxidants. Haeme oxygenase (HO)-1 mRNA levels were analysed by quantitative polymerase chain reaction. Apoptosis was quantified by acridine orange staining and caspase-3 activity assay. Necrosis was detected by Sytox green staining.


RESULTS
Anti-oxidants do not attenuate bile acid-induced cell death. Furthermore, bile acid exposure does not enhance the mRNA expression of the oxidative stress-responsive gene HO-1. The Src-kinase inhibitor, SU6656, does reduce GCDCA-induced apoptosis and necrosis.


CONCLUSIONS
In hepatocytes, bile acid-induced toxicity is not prevented by scavengers of oxidative stress. The beneficial effects observed in patients might be because of the contribution of ROS and cytokines rather than bile acid-mediated oxidative stress. However, the use of specific Src kinase inhibitors might be a useful tool to prevent bile acid-induced injury in liver diseases.
Woudenberg-Vrenken
Titia E
TE
Department of Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
Buist-Homan
Manon
M
Conde de la Rosa
Laura
L
Faber
Klaas Nico
KN
Moshage
Han
H
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D002478:Cells, Cultured; D019610:Cytoprotection; D005999:Glycochenodeoxycholic Acid / Q000378:metabolism*; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics / Q000378:metabolism; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D019255:NADPH Oxidases / Q000037:antagonists & inhibitors / Q000378:metabolism; D009336:Necrosis; D018384:Oxidative Stress / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011924:Rats, Zucker; D017382:Reactive Oxygen Species / Q000378:metabolism; D013658:Taurolithocholic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
D000975:Antioxidants; D047428:Protein Kinase Inhibitors; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; C066776:taurolithocholic acid 3-sulfate; D013658:Taurolithocholic Acid; D005999:Glycochenodeoxycholic Acid; D006419:Heme Oxygenase (Decyclizing); C491523:Hmox1 protein, rat; D019255:NADPH Oxidases; D019061:src-Family Kinases; C505410:Casp3 protein, rat; D053148:Caspase 3