Involvement of p38 MAP kinase in lipopolysaccharide-induced production of pro- and anti-inflammatory cytokines and prostaglandin E(2) in human choriodecidua.
Chorioamnionitis is implicated in the pathogenesis of preterm delivery. However, the detailed mechanisms by which infection induces preterm labor are not well understood. This study has assessed the involvement of mitogen-activated protein (MAP) kinases in lipopolysaccharide (LPS)-induced pro- and anti-inflammatory cytokine and prostaglandin (PG) production in human choriodecidua. Samples of choriodecidua were collected before the onset of labor from women undergoing elective cesarean sections at term for breech presentation, previous cesarean delivery or cephalopelvic disproportion. Concentrations of TNFalpha, IL-10, PGE(2) and PGF(2)alpha in culture supernatants were measured by ELISA. Expression of COX-2 protein was analyzed by Western blotting. In human choriodecidual explants, LPS induced TNFalpha and IL-10 production in a dose- and time-dependent manner. LPS also up-regulated COX-2 expression and PG synthesis. Phosphorylations of extracellular signal-regulated kinase (ERK) 1/2, p38 MAPK, and c-Jun N-terminal kinases (JNK) were also confirmed by Western blotting. Furthermore, the effect of MAPK inhibitors was examined on LPS-induced pro- and anti-inflammatory cytokines and PG synthesis. Among the MAPK inhibitors examined, the p38 MAPK inhibitor, SB202190, significantly suppressed LPS-induced cytokine and PG production. SB202190 most profoundly suppressed the TNFalpha to IL-10 ratio, demonstrating that p38 MAPK inhibitor reduced predominantly TNFalpha other than IL-10 production. Phospho-p38 MAPK immunostaining was intense in extravillous trophoblast cells. The p38 MAPK seems to be most involved in signaling mechanisms when infection and inflammation cause preterm labor through PG synthesis. Novel therapeutic modalities targeting p38 MAPK may prevent to arrest preterm labor.
Shoji
Takako
T
Department of Obstetrics and Gynecology, Tottori University School of Medicine, 36-1 Nishimachi, Yonago, Japan.
Yoshida
Souichi
S
Mitsunari
Masahiro
M
Miyake
Noriko
N
Tsukihara
Satoru
S
Iwabe
Tomio
T
Harada
Tasuku
T
Terakawa
Naoki
N
D051546:Cyclooxygenase 2 / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism*; D003656:Decidua / Q000378:metabolism*; D015232:Dinoprostone / Q000378:metabolism*; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D008070:Lipopolysaccharides / Q000276:immunology*; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D011247:Pregnancy; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
D016207:Cytokines; D018836:Inflammation Mediators; D008070:Lipopolysaccharides; D047428:Protein Kinase Inhibitors; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D015232:Dinoprostone