The Joint Annual Scientific Meetings of the Endocrine Society of Australia and the Society for Reproductive Biology 2018

Endometrial miRNA profile varies with maternal age in a novel bovine model (#376)

Bethany J Finger 1 , Martin C Berg 2 , Rita SF Lee 2 , Mark P Green 1 2
  1. School of BioSciences, University of Melbourne, Parkvile, VIC, Australia
  2. AgResearch Ltd, Ruakura Research Centre, Hamilton, New Zealand

Increasing maternal age is associated with decreased endometrial receptivity, and thus diminished fertility in both humans and domestic species. Endometrial microRNAs (miRNAs) play an important role in establishing an optimal uterine environment, and thus the successful establishment of a pregnancy. The aim of this study was to determine the variability of endometrial miRNA with maternal age, using a novel bovine model that removes potential confounders of nuclear genetics, environment and diet. Endometrium samples of five young (4 years old, equivalent to women in their mid-twenties) and five old (11 years old, equivalent to women >37 years old) cloned cows with an identical genetic background, and managed as one herd, were collected on day 7 of a natural cycle, and total RNA was extracted. Through Next-Generation Sequencing, 786 differentially expressed transcripts were identified between the young and old group. Of those, 46 were significantly different after FDR correction (p<0.05) including increased levels of mir99A, mir140, mir125a, mir125b and mir145 in the old group. Further studies are required to confirm the functional pathways effected as well as the expression of regulated genes, and the role these may play in endometrial receptivity.