[Role of IL-6/STAT3 in rat cholangiocyte proliferation induced by lipopolysaccharide].
OBJECTIVE
To investigate whether lipopolysaccharide (LPS) stimulates cholangiocyte proliferation via the IL-6/STAT3 pathway in vivo.


METHODS
Rats were randomized into three groups: LPS group (injected intravenously with LPS 2.5 mg/kg), anti-IL-6 group (injected intravenously with anti-IL-6 0.5 mg/kg 1hr after LPS injection), and control group. At 6, 12, 24, 48 and 72 h after LPS injection, LPS concentration in plasma was detected by kinetic turbidimetric limulus test. IL-6 concentrations in liver homogenate was determinded by ELISA, cholangiocyte proliferation was checked by immunohistochemistry, expression of IL-6 mRNA was quantified by real-time RT-PCR, the level of phophorylated-STAT3 (P-STAT3) protein was analyzed by western blotting.


RESULTS
Cholangiocytes responded to LPS by a marked increase in cell proliferation, IL-6 secretion and P-STAT3 expression. Anti-IL-6 neutralizing antibody inhibited LPS-induced cholangiocytes proliferation, and decreased levels of IL-6 and p-STAT3.


CONCLUSIONS
LPS promotes cholangiocyte proliferation through the IL-6/STAT3 pathway.
CHEN
Li-ping
LP
Organ Transplantation Center, Second Affiliated Hospital, Chinese People's Liberation Army General Hospital, Beijing 100091, China.
QIAN
Ye-yong
YY
LI
Zhou-li
ZL
BAI
Hong-wei
HW
CAI
Ming
M
SHI
Bing-yi
BY
D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D001653:Bile Ducts, Intrahepatic / Q000166:cytology*; D049109:Cell Proliferation; D004847:Epithelial Cells / Q000166:cytology / Q000502:physiology*; D007150:Immunohistochemistry; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000097:blood / Q000494:pharmacology; D008099:Liver / Q000378:metabolism; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D015398:Signal Transduction
D000911:Antibodies, Monoclonal; D015850:Interleukin-6; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D050796:STAT3 Transcription Factor; C494088:Stat3 protein, rat