title: Changes in the expression of toll-like receptor mRNAs during follicular growth and in response to lipopolysaccharide in the ovarian follicles of laying hens.
abstract: The aim of this study was to determine the changes in the mRNA expression of Toll-like receptors (TLRs) in hen ovarian follicles during follicular growth and in response to lipopolysaccharide (LPS). White follicles and the fifth largest to largest follicles (WF and F(5)-F(1), respectively) were collected from laying hens. To examine the effects of LPS, the laying hens were treated intravenously with LPS (1 mg/kg BW) 0, 3, 6, 12 and 24 h before examination. Expressions of TLRs and IL-1beta in the theca and granulosa layers were examined by semi-quantitative RT-PCR. Immunocytochemistry was performed to identify immunoreactive TLR-4. The theca layer expressed TLR-2, TLR-4, TLR-5 and TLR-7, whereas the granulosa layer expressed only TLR-4 and TLR-5. The expression of TLR-4 and TLR-5 in the theca layer increased significantly during follicular growth. In the granulosa layer, the expression of TLR-5 increased, but that of TLR-4 was unchanged. Expression of TLR-4 increased significantly during the period of 6 to 12 h of LPS treatment in the theca layer and during the period of 12 to 24 h in the granulosa layer of F(3). Immunoreaction products for TLR-4 were observed in theca interna and granulosa layers of WF and F(5)-F(1), with the greater amount observed in the theca interna. LPS treatment significantly increased expression of IL-1beta in the theca layer after 3 h and in the granulosa layer during the period of 12 to 24 h. These results suggest that TLRs are expressed in ovarian follicles and that TLR-4 and TLR-5 expression increase with the growth of follicles. Enhanced expression of TLR-4 and IL-1beta by LPS in the theca and granulosa layers suggests possible roles of TLR in recognition of microorganisms.
authors.affiliation: Graduate School of Biosphere Science, Hiroshima University Higashi-Hiroshima, Japan.
authors.forename: Kalpana
authors.initials: K
authors.lastname: Subedi
authors.forename: Naoki
authors.initials: N
authors.lastname: Isobe
authors.forename: Masahide
authors.initials: M
authors.lastname: Nishibori
authors.forename: Yukinori
authors.initials: Y
authors.lastname: Yoshimura
mesh_terms: D000818:Animals; D002645:Chickens; D005260:Female; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D006107:Granulosa Cells / Q000187:drug effects / Q000502:physiology; D053583:Interleukin-1beta / Q000235:genetics; D008070:Lipopolysaccharides / Q000494:pharmacology*; D006080:Ovarian Follicle / Q000187:drug effects* / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D013799:Theca Cells / Q000187:drug effects / Q000502:physiology; D051195:Toll-Like Receptor 2 / Q000235:genetics; D051197:Toll-Like Receptor 4 / Q000235:genetics; D051198:Toll-Like Receptor 5 / Q000235:genetics; D051199:Toll-Like Receptor 7 / Q000235:genetics; D051193:Toll-Like Receptors / Q000235:genetics*
chemical_list: D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051198:Toll-Like Receptor 5; D051199:Toll-Like Receptor 7; D051193:Toll-Like Receptors