Kupffer cell depletion with liposomal clodronate prevents suppression of Ntcp expression in endotoxin-treated rats.
OBJECTIVE
In sepsis-associated cholestasis, expression of many genes involved in bile acid transport, including Ntcp, is suppressed by cytokines. Kupffer cells (KC) are an important source of cytokines in sepsis. To assess the consequences of KC depletion on hepatic Ntcp expression in endotoxemic rats.


METHODS
Sprague-Dawley rats received liposomal clodronate (CLO) or vehicle (PBS) to deplete KC prior to lipopolysaccharide (LPS) exposure. Plasma and liver samples were taken 1 and 16 h after LPS exposure.


RESULTS
Complete CLO-depletion of KC by was demonstrated by immunohistochemistry. Hepatic gene expression of IL-1beta and TNFalpha as well as TNFalpha plasma levels in CLO/LPS-injected animals were significantly reduced to a mean of 41, 36 and 23% of controls injected with LPS only. Ntcp RNA- and protein expression was significantly higher whereas plasma bile salt concentration was lower in CLO/LPS animals vs. animals injected with LPS only. Binding activity of transcription factors RXR:RAR and HNF1alpha was decreased in LPS only controls but preserved in CLO/LPS treated animals.


CONCLUSIONS
Clodronate-depletion of KC blocks cytokine-mediated Ntcp suppression upon endotoxin exposure. KC may represent pharmacological targets for treatment of sepsis-associated cholestasis.
Sturm
Ekkehard
E
Department of Pediatrics, Center for Liver, Digestive, and Metabolic Diseases, University of Groningen, The Netherlands. e.sturm@bkk.azg.nl
Havinga
Rick
R
Baller
Julius F W
JF
Wolters
Henk
H
van Rooijen
Nico
N
Kamps
Jan A A M
JA
Verkade
Henkjan J
HJ
Karpen
Saul J
SJ
Kuipers
Folkert
F
D000818:Animals; D002779:Cholestasis / Q000188:drug therapy; D004002:Clodronic Acid / Q000008:administration & dosage*; D004268:DNA-Binding Proteins / Q000378:metabolism; D051537:Hepatocyte Nuclear Factor 1; D051538:Hepatocyte Nuclear Factor 1-alpha; D007375:Interleukin-1 / Q000096:biosynthesis; D007728:Kupffer Cells / Q000187:drug effects* / Q000502:physiology; D008070:Lipopolysaccharides / Q000633:toxicity*; D008081:Liposomes; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics*; D009687:Nuclear Proteins / Q000378:metabolism; D029363:Organic Anion Transporters, Sodium-Dependent; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D018168:Receptors, Retinoic Acid / Q000378:metabolism; D047488:Retinoid X Receptors / Q000235:genetics; D027981:Symporters; D014157:Transcription Factors / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D004268:DNA-Binding Proteins; D051538:Hepatocyte Nuclear Factor 1-alpha; C496489:Hnf1a protein, rat; D007375:Interleukin-1; D008070:Lipopolysaccharides; D008081:Liposomes; D026901:Membrane Transport Proteins; D009687:Nuclear Proteins; D029363:Organic Anion Transporters, Sodium-Dependent; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; D047488:Retinoid X Receptors; D027981:Symporters; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; D004002:Clodronic Acid; D051537:Hepatocyte Nuclear Factor 1; C071908:sodium-bile acid cotransporter