Effect of growth factors (epidermal growth factor, platelet derived growth factor, and insulin-like growth factor-1) on buffalo embryos produced in vitro

Abstract

The present study examined effect of epidermal growth factor (EGF) on buffalo oocytes maturation and its subsequent effect on embryo development when embryos cultured in media supplemented either with insulin-like growth factor-1 (IGF-1) or/and platelet-derived growth factor (PDGF). Slaughterhouse derived excellent to good quality oocytes were matured for 24 h in TCM-199 supplemented with epidermal growth factor (EGF, 20ng/ml) and without EGF (control), 10% follicular fluid and 10% fetal bovine serum. Matured oocytes were fertilized with frozen buffalo bull semen. Presumptive zygotes were divided and cultured in 4 groups each: Group 1 (control, containing mSOF+ ß-mercaptoethanol, 100µM), group 2 (control + IGF-1, 100ng/ml), group 3 (control+ PDGF, 1ng/ml) and group 4 (control+ IGF-1 +PDGF). Maturation rate was higher in EGF supplemented group compared to control group (85.7% vs 67.5%). Cleavage rate was also higher in EGF supplemented groups. Overall developmental rate of in vitro produced embryos was significantly higher in EGF supplemented group except in PDGF supplemented groups. PDGF supplemented group showed highest cleavage when oocytes matured with EGF (42.0% and 45.5%) but was not able to convert proportionate embryos to blastocyst (15.9% and 18.5%) while IGF-1 supplemented group showed highest percentage of blastocysts (29.7%). These results indicated that addition of IGF-1 (100ng/ml) improved the cleavage and blastocyst production rate, whereas PDGF (1ng/ml) though improved cleavage significantly but showed comparatively low blastocyst production rate. It can be concluded that oocytes matured in EGF (20ng/ml) and subsequently cultured in IGF-1 (100ng/ml) supplemented media have greater embryonic developmental potential.