IGF-1 treatment duringin vitromaturation improves developmental potential of ovine oocytes through the regulation of PI3K/Akt and apoptosis signaling

This study aimed to assess the effect of the insulin-like grow factor 1 (IGF-1) treatment duringin vitromaturation on the gene expression and developmental ability of ovine oocytes. Ovine cumulus-oocyte complexes (COC) were maturedin vitrowithout (control) or with the supplementation of IGF-1 (100 ng/ml) and then subjected toin vitrofertilization and culture. The rate of oocyte maturation and embryo development was recorded and expression of the selected genes (involved in the PI3K/Akt and apoptosis signaling) was assessed in the matured oocytes. The IGF-1 treatment significantly (p < .05) improved the oocyte maturation rate (%) as compared to the control (81.5 +/- 2.40 vs. 73.6 +/- 0.94). Similarly, as compared to the control, the IGF-1 treatment significantly (p < .05) improved the rate (%) of cleavage (54.7 +/- 1.58 vs. 67.2 +/- 3.65) and the formation of 4-8 cell embryos (30.7 +/- 2.89 vs. 44.1 +/- 4.01) and morula (20.7 +/- 2.08 vs. 32.8 +/- 2.78). The IGF-1 treatment significantly (p < .05) upregulated the expression ofIGF1R,PI3KR1,AKT1andBCL2and downregulated the expression ofGSK3 beta,FOXO3andCASP9in the matured oocytes. In conclusion, the IGF-1 treatment significantly improved the developmental competence of ovine oocytes through the regulation of the PI3K/Akt and apoptosis signaling.

Automated summary

The study showed that IGF-1 treatment significantly improved the developmental competence of ovine oocytes, enhancing the maturation rate and embryo development. This effect was achieved through the regulation of the PI3K/Akt and apoptosis signaling pathways.