Location: Reproduction ResearchTitle: Non-targeted metabolomic evaluation of the uterine milieu during the transitional period of embryo elongation in the pig
|LAUGHLIN, TAYLOR - University Of Nebraska|
|BROECKLING, COREY - Colorado State University|
|PANNIER, ANGELA - University Of Nebraska|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 4/21/2016
Publication Date: 7/19/2016
Citation: Miles, J.R., Wright-Johnson, E.C., Laughlin, T.D., Broeckling, C.D., Rempel, L.A., Pannier, A.K. 2016. Non-targeted metabolomic evaluation of the uterine milieu during the transitional period of embryo elongation in the pig [abstract]. Journal of Animal Science Supplement. 94 (E-Supplement 5):503-504 (Abstract # 1070).
Technical Abstract: Alterations in the signaling of critical molecular factors within the uterine milieu lead to deficiencies in embryo elongation. The objective of this study was to identify metabolites within the uterine environment that are present as porcine embryos transition between spherical, ovoid, and tubular embryos at day 9, 10 and 11 of gestation, respectively. White crossbred gilts (n = 9) were bred at standing estrus (designated d 0) and again 24 h later and randomly assigned to collection group. At day 9, 10, or 11 of gestation (n = 3 per day), reproductive tracts were collected immediately following harvest and flushed with 40 ml of RPMI-1640 media. Embryo morphologies were assessed for each pregnancy to ensure gilts were assigned to the correct gestation day treatment group (i.e., day 9 contained only spherical conceptuses, day 10 contained only ovoid conceptuses, and day 11 contained a mixture of ovoid and tubular conceptuses). Subsequent uterine flushings were submitted for non-targeted profiling by GC-MS and UPLC-MS techniques. Raw spectral data was processed using XCMS package in R and features were clustered using RAMclustR. Unsupervised multivariate principal component analysis (PCA) was performed in R using pcamethods package and univariate ANOVA was performed in R with a Benjamini-Hochburg false discovery rate (FDR) adjustment. Multivariate analysis of both the GC-MS and UPLC-MS spectral data demonstrated sample grouping that reflected the day of gestation. Maximum separation for the GC-MS data over time was observed with PC1 vs. PC2 accounting for 90% of the variance and PC2 identified several significant (P = 0.03) putative metabolites that changed over time. For the UPLC-MS data, separation over time was not as obvious but PC2 vs. PC6 did account for 28% of the variance and PC2 identified some significant (P = 0.04) metabolites that changed with time. After FDR adjustment of the GC-MS and UPLC-MS data, only C553, an unknown compound, was significantly (P = 0.02) greater in day 11 uterine flushings compared to day 9 and 10. However, several annotated compounds were trending towards differences, including aminomalonic acid which tended to be increased (P = 0.07) in day 11 uterine flushings compared to day 9 and 10. In conclusion, these data illustrate putative metabolites that change within the uterine milieu as porcine embryos transition between spherical, ovoid, and tubular embryos.