title: Controlled ovarian hyperstimulation induced changes in the expression of circulatory miRNA in bovine follicular fluid and blood plasma.
abstract: BACKGROUND
  Despite its role in increasing the number of offspring during the lifetime of an individual animal, controlled ovarian hyperstimulation (COH) may have detrimental effects on oocyte development, embryo quality and endometrial receptivity. Circulating miRNAs in bio-fluids have been shown to be associated with various pathological conditions including cancers. Here we aimed to investigate the effect of COH on the level of extracellular miRNAs in bovine follicular fluid and blood plasma and elucidate their mode of circulation and potential molecular mechanisms to be affected in the reproductive tract.
  
  
  METHODS
  Twelve simmental heifers were estrous synchronized and six of them were hyperstimulated using FSH. Follicular fluid samples from experimental animals were collected using ovum pick up technique at day 0 of the estrous cycle and blood samples were collected at day 0, 3 and 7 of post ovulation. The expression profile of circulatory miRNAs in follicular fluid and blood plasma were performed using the human miRCURY LNA™ Universal RT miRNA PCR array system. A comparative threshold cycle method was used to determine the relative abundance of the miRNAs.
  
  
  RESULTS
  A total of 504 and 402 miRNAs were detected in both bovine follicular fluid and blood plasma, respectively. Of these 57 and 21 miRNAs were found to be differentially expressed in follicular fluid and blood plasma, respectively derived from hyperstimulated versus unstimulated heifers. Bioinformatics analysis of those circulating miRNAs indicated that their potential target genes are involved in several pathways including TGF-beta signaling pathway, MAPK signaling pathway, pathways in cancer and Oocyte meiosis. Moreover, detail analysis of the mode of circulation of some candidates showed that most of the miRNA were found to be detected in both exosomal and Ago2 protein complex fraction of both follicular fluid and blood plasma.
  
  
  CONCLUSIONS
  Our data provide the consequence of hyperstimulation induced changes of extracellular miRNAs in bovine follicular fluid and blood plasma, which may have a potential role in regulating genes associated not only with bovine ovarian function but also involved in altering various physiological in bovine oocytes, embryos and modulating reproductive tract environment.
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany.
authors.forename: Sina Seifi
authors.initials: SS
authors.lastname: Noferesti
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany.|Department of Animal Science, Faculty of Agriculture, Erciyes University, Kayseri, 38039, Turkey.
authors.forename: Md Mahmodul Hasan
authors.initials: MM
authors.lastname: Sohel
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Hoelker
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany.
authors.forename: Dessie
authors.initials: D
authors.lastname: Salilew-Wondim
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany.
authors.forename: Ernst
authors.initials: E
authors.lastname: Tholen
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Looft
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany.
authors.forename: Franca
authors.initials: F
authors.lastname: Rings
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany.
authors.forename: Christiane
authors.initials: C
authors.lastname: Neuhoff
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany.
authors.forename: Karl
authors.initials: K
authors.lastname: Schellander
authors.affiliation: Animal Breeding and Husbandry Group, Institute of Animal Science, University of Bonn, Bonn, 53115, Germany. tesfaye@itw.uni-bonn.de.
authors.forename: Dawit
authors.initials: D
authors.lastname: Tesfaye
mesh_terms: D000818:Animals; D060565:Argonaute Proteins / Q000378:metabolism; D002417:Cattle; D004971:Estrus / Q000502:physiology; D055354:Exosomes / Q000378:metabolism; D005260:Female; D015571:Follicular Fluid / Q000378:metabolism*; D035683:MicroRNAs / Q000378:metabolism*; D010062:Ovulation Induction / Q000379:methods / Q000662:veterinary*; D010949:Plasma / Q000378:metabolism; D011374:Progesterone / Q000378:metabolism
chemical_list: D060565:Argonaute Proteins; D035683:MicroRNAs; D011374:Progesterone