140 Effect of addition of different concentrations of l-carnitine during porcine in vitro maturation on embryo quality and development
P. R. Cruzans B , M. S. Lorenzo A B , G. M. Teplitz A B , C. G. Luchetti A B and D. M. Lombardo A BA Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina;
B Instituto de Investigación y Tecnología en Reproducción Animal, Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, Buenos Aires, Argentina
Reproduction, Fertility and Development 33(2) 178-178 https://doi.org/10.1071/RDv33n2Ab140
Published: 8 January 2021
Abstract
l-Carnitine (LC) plays an important role in the catabolism of lipids and protects cells from the damage caused by reactive oxygen species due to its antioxidant activity. The aim of this study was to evaluate the effect of adding different concentrations of LC during porcine in vitro maturation on embryo quality and development. The cumulus–oocyte complexes were obtained by follicular aspiration from ovaries of slaughtered sows and matured in vitro for 44 h without LC (control) or with different concentrations of LC (0.6 or 1.25 mg mL−1) (Sigma-Aldrich) in TCM-199 supplemented with human menopausal gonadotrophin and cyclic AMP (cAMP) during the first 22 h. In vitro fertilization was performed with fresh boar semen for 4 h in 100-µL drops of TCM-199 with caffeine, bovine serum albumin, sodium lactate, and pyruvate (20 denuded oocytes per drop, 1 × 106 spermatozoa mL−1). Presumptive zygotes were washed and cultured in NCSU 23 at 39°C, 7% O2, 5% CO2, and humidity. The cleavage rate was registered on Day 2 and the blastocyst rate on Day 7. Embryo quality was assessed by counting the number of cells per blastocyst (Hoescht 33342) and late apoptosis index (TUNEL-positive cells/total cells). Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) was performed according to the kit protocol (Roche). LC significantly decreased the cleavage rate (control: 46.2%; LC0.6: 32.1%; LC1.25: 37.9%; P < 0.05, Chi-squared test). No significant differences were detected in the blastocyst rate (control: 19.2%; LC0.6: 17%; LC1.25: 10,2%, Chi-squared test) or in number of cells per blastocyst (control: 51.97 ± 3; LC0.6: 56.11 ± 4; LC1.25: 45.62 ± 4, ANOVA). There was embryo hatching in LC treatments but not in the control (control: 0%, LC0.6: 11%; LC1.25: 7.6%). The apoptosis index decreased in LC1.25 compared with LC0.6 (Control: 7,6 ± 1.3%; LC0.6: 10 ± 1.1%; LC1.25: 5,5 ± 0.8%; P < 0.05, ANOVA) but there was no significant difference in the apoptosis index between control and LC treatments. In conclusion, LC treatments decreased the cleavage rate but did not modify the blastocyst rate and allowed embryo hatching.
