Myometrial tumor necrosis factor-α receptors increase with gestation and labor and modulate gene expression through mitogen-activated kinase and nuclear factor-κB.
Previously, we found that myometrial tumor necrosis factor-α (TNF-α) messenger RNA (mRNA) expression did not increase with preterm or term labor. To further investigate the role of TNF-α in human labor, we studied TNF-α receptor (TNFR1A and B) expression, regulation, and associated intracellular signaling pathways in human myometrial samples obtained both before and after the onset of labor and in primary cultures of uterine smooth muscle cells (USMCs). We found that the mRNA expression of both receptors increased with advancing gestation and labor and protein levels of TNFR1B were significantly higher in term laboring myometrial samples than in nonlabor controls. Tumor necrosis factor- treatment of USMCs activated all mitogen-activated protein kinase (MAPK) subtypes and nuclear factor κ-B (NF-κB). The TNF-α induced increases in the expression of TNFR1B and prostaglandin H synthase type 2 were reduced by inhibitors of NF-κB and MAPKs, respectively. The TNF-α induced increase in interleukin 8 (IL-8) appeared to be independent of MAPK and NF-κB pathway. These data suggest that the uterus may become more sensitive to the action of TNF-α with advancing gestation and labor and that TNF-α acts via MAPK and NF-κB to promote labor-associated gene expression.
Imperial College Parturition Research Group, Academic Department of Obstetrics & Gynaecology, Imperial College School of Medicine Chelsea and Westminster Hospital, London, UK.
Helen A
HA
Alexander
Suren R
SR
Sooranna
Leslie
L
Myatt
Mark R
MR
Johnson
D002478:Cells, Cultured; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007743:Labor, Obstetric / Q000235:genetics / Q000378:metabolism*; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism*; D009215:Myometrium / Q000166:cytology / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism*; D011247:Pregnancy / Q000378:metabolism*; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000378:metabolism* / Q000502:physiology; D047889:Receptors, Tumor Necrosis Factor, Type II / Q000378:metabolism* / Q000502:physiology
D016328:NF-kappa B; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D020929:Mitogen-Activated Protein Kinase Kinases