Lipopolysaccharides selectively inhibit mouse placental lactogen-II secretion through stimulation of interleukin-1 alpha (IL-1 alpha) and IL-6 production.
To determine whether lipopolysaccharides (LPS) regulate mouse placental lactogen-I (mPL-I), mPL-II, and mouse GHRF (mGHRF) secretion, mouse placental tissue from days 7, 9, and 12 of pregnancy was dispersed with collagenase and the purified trophoblast cells were cultured in a serum-free medium with or without LPS for 5 days. LPS significantly inhibited mPL-II secretion by cells from days 9 and 12 of pregnancy. However, LPS did not affect mPL-II secretion by cells from day 7 of pregnancy, mPL-I secretion by cells from days 7 and 9 of pregnancy, or mGHRF secretion by cells from day 12 of pregnancy. The inhibitory effect of LPS on mPL-II secretion by cells from day 12 of pregnancy was dose-dependent. Steady-state levels of mPL-II mRNA were significantly reduced by incubation of placental cells from day 12 of pregnancy with LPS. The inhibitory effect of LPS on mPL-II secretion was abolished by the addition of antibodies to IL-1 alpha and IL-6. These findings suggest that LPS selectively inhibit mPL-II secretion, at least partly through increases in IL-1 and IL-6 production, after midpregnancy.
Yamaguchi
M
M
Osaka University Medical School, Japan.
Sawada
K
K
Miyake
A
A
D000818:Animals; D000906:Antibodies / Q000276:immunology; D015152:Blotting, Northern; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005260:Female; D013007:Growth Hormone-Releasing Hormone / Q000187:drug effects / Q000378:metabolism; D007375:Interleukin-1 / Q000037:antagonists & inhibitors / Q000276:immunology / Q000502:physiology*; D015850:Interleukin-6 / Q000276:immunology / Q000502:physiology*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D051379:Mice; D008813:Mice, Inbred ICR; D010920:Placenta / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010928:Placental Lactogen / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D011247:Pregnancy; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D011863:Radioimmunoassay; D013997:Time Factors; D000093242:Interleukin-6 Inhibitors
D000906:Antibodies; D013007:Growth Hormone-Releasing Hormone; D007375:Interleukin-1; D015850:Interleukin-6; D008070:Lipopolysaccharides; D010928:Placental Lactogen; D012333:RNA, Messenger; D000093242:Interleukin-6 Inhibitors