title: Estrogen inhibits interleukin-18 mRNA expression in the mouse uterus.
abstract: Interleukin-18 (IL-18) is a proinflammatory cytokine expressed in female reproductive organs in humans, rats and mice. The physiological roles of uterine IL-18 and the regulatory mechanisms of IL-18 gene expression are unclear. The present study aimed to clarify the effects of estradiol-17beta (E2) and progesterone (P4) on IL-18 mRNA expression in the mouse uterus. Distribution and expression levels of IL-18 mRNA were studied using an RNase protection assay. Expression of IL-18 mRNA was observed in all organs studied, including testes, ovaries and uteri. The uterine IL-18 mRNA level of estrous mice was higher than that of diestrous mice. E2 treatment (1, 5, 25 or 250 ng/mouse) decreased uterine IL-18 mRNA levels in ovariectomized mice dose-dependently. E2 treatment acutely decreased IL-18 mRNA levels 3 h after injection, but these levels returned to the initial level after 48 h. P4 treatment (1 mg/mouse) decreased uterine IL-18 mRNA levels after 12 h, but levels returned to the initial level after 48 h. Both uterine IL-18 and IL-18Ralpha mRNAs were detected in cultured endometrial epithelial and stromal cells. These results suggest that uterine IL-18 expression is reduced by sex steroid hormones and that IL-18 acts on endometrial cells in a paracrine or autocrine manner.
authors: Department of Biology, Faculty of Science, Okayama University, Japan.
authors: Yousuke
authors: Y
authors: Murakami
authors: Mariko
authors: M
authors: Otsuki
authors: Kenji
authors: K
authors: Kusumoto
authors: Sakae
authors: S
authors: Takeuchi
authors: Sumio
authors: S
authors: Takahashi
mesh_terms: D000818:Animals; D004847:Epithelial Cells / Q000502:physiology; D004958:Estradiol / Q000494:pharmacology*; D030762:Estrous Cycle / Q000502:physiology; D005260:Female; D020382:Interleukin-18 / Q000096:biosynthesis* / Q000235:genetics; D053727:Interleukin-18 Receptor alpha Subunit; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010052:Ovariectomy; D011374:Progesterone / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D018123:Receptors, Interleukin / Q000096:biosynthesis / Q000235:genetics; D053724:Receptors, Interleukin-18; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012260:Ribonucleases / Q000378:metabolism; D017154:Stromal Cells / Q000502:physiology; D014599:Uterus / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology
chemical_list: C508573:Il18r1 protein, mouse; D020382:Interleukin-18; D053727:Interleukin-18 Receptor alpha Subunit; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D053724:Receptors, Interleukin-18; D011374:Progesterone; D004958:Estradiol; D012260:Ribonucleases