title: Repeated intrauterine infusions of lipopolysaccharide alter gene expression and lifespan of the bovine corpus luteum.
abstract: Inflammation of the uterus is associated with disturbed ovarian function and reduced reproductive performance in dairy cows. To investigate the influence of endometritis on the bovine corpus luteum, 8 heifers received intrauterine infusions with either phosphate-buffered saline (PBS; 9mL) or Escherichia coli lipopolysaccharide (LPS; 3µg/kg of body weight diluted in 9mL of PBS) at 6-h intervals from 12h before and until 9d after ovulation during 2 cycles in a random order (ovulation=d 1). An untreated cycle was examined before and after PBS and LPS cycles, and the mean values from both untreated cycles were used as control. In all cycles, blood sampling and ultrasonography of the ovaries were performed on d 0, 1, 2, 4, 6, 8, 9, 10, 12, 15, 18, and then every 2d until ovulation. Endometrial cells were collected for cytology and quantitative real-time reverse transcriptase PCR on d 0, 6, and 9, and on d 0 and 6, respectively, and luteal tissue was collected for quantitative real-time reverse transcriptase PCR on d 6 and 9. Both, PBS and LPS infusions induced subclinical endometritis, which was accompanied by increased endometrial mRNA abundance of proinflammatory cytokines IL1β, IL8, and tumor necrosis factor α. Additionally, LPS challenge induced premature luteolysis, which was characterized by increased plasma concentrations of PGF2α metabolite, decreased plasma progesterone concentrations, and reduced luteal size and blood flow compared with the control. The luteal mRNA expression of the LPS receptor TLR4, PGE synthase, and the apoptosis-related factor CASP3 were higher, and those of steroidogenic factors STAR and HSD3B, the PGF receptor, and the angiogenic factor VEGFA121 were lower after LPS challenge compared with the control. In conclusion, repeated intrauterine LPS infusions during the first 9d of the estrous cycle alter gene expression and shorten the lifespan of the bovine corpus luteum.
authors.affiliation: Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland. Electronic address: jluettgenau@vetclinics.uzh.ch.
authors.forename: J
authors.initials: J
authors.lastname: Lüttgenau
authors.affiliation: Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland.
authors.forename: B
authors.initials: B
authors.lastname: Lingemann
authors.affiliation: Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland; Veterinary Physiology, Vetsuisse Faculty, University of Bern, CH-3001 Bern, Switzerland.
authors.forename: O
authors.initials: O
authors.lastname: Wellnitz
authors.affiliation: ETH Zurich, Animal Physiology, Institute of Agricultural Sciences, CH-8092 Zurich, Switzerland.
authors.forename: A K
authors.initials: AK
authors.lastname: Hankele
authors.affiliation: Clinic for Cattle, University of Veterinary Medicine Hannover, D-30173 Hannover, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Schmicke
authors.affiliation: ETH Zurich, Animal Physiology, Institute of Agricultural Sciences, CH-8092 Zurich, Switzerland.
authors.forename: S E
authors.initials: SE
authors.lastname: Ulbrich
authors.affiliation: Veterinary Physiology, Vetsuisse Faculty, University of Bern, CH-3001 Bern, Switzerland.
authors.forename: R M
authors.initials: RM
authors.lastname: Bruckmaier
authors.affiliation: Clinic of Reproductive Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH-8057 Zurich, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Bollwein
mesh_terms: D000818:Animals; D002417:Cattle; D003338:Corpus Luteum; D015237:Dinoprost / Q000494:pharmacology; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D003341:Luteolysis / Q000187:drug effects; D011374:Progesterone / Q000097:blood; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D011374:Progesterone; D015237:Dinoprost
keywords: corpus luteum; endometritis; endotoxin; heifer