Effect of insulin-like growth factor I (IGF-I) at high concentrations on blastocyst development of bovine embryos produced in vitro

Abstract

This study was carried out to determine the effects of oestrous cow serum containing insulin-like growth factor I (IGF-I) and supplementation with recombinant IGF-I on subsequent development of bovine embryos produced in vitro. When culture medium was supplemented with oestrous cow serum containing 34.8 ng endogenous IGF-I ml-1, more embryos (P < 0.01) developed to blastocysts by day 9 and more blastocysts hatched on day 13 after insemination (P < 0.01) than in the control group. The effect of the addition of 10, 50 and 100 ng IGF-I ml-1 to culture media containing oestrous cow serum and granulosa cells was also evaluated. Supplementation with 10 ng IGF-I ml-1 did not improve embryo development at any stage. The addition of 50 and 100 ng IGF-I ml-1 did not affect development during the first three cell divisions. However, on day 7 these groups yielded a higher embryo rate than did the control group. Similarly, the proportion of blastocysts on day 9 was enhanced. The addition of 100 ng IGF-I ml-1 also increased the proportion of blastocysts. These data suggest that IGF-I at high concentrations accelerates the development to the blastocyst stage by shortening the transition from the morula to the blastocyst stage. The addition of 100 ng IGF-I ml-1 increased the proportion of hatched blastocysts on day 13. The addition of oestrous cow serum and IGF-I to TCM 199 free of granulosa cells did not increase the proportion of embryos on day 7. However, the progress to blastocysts and hatched blastocysts on days 9 and 13 was significantly lower (P < 0.05). The addition of IGF-I to culture medium without oestrous cow serum but with granulosa cells resulted in significantly lower embryo development than in the control group or in the group supplemented with oestrous cow serum and IGF-I (P < 0.01). The results support the hypothesis that culture media containing high concentrations of IGF-I combined with oestrous cow serum and granulosa cells can improve the development of embryos produced in vitro.

The role of IGF1 in the in vivo production of bovine embryos from superovulated donors

“…A positive effect of IGF1 on embryogenesis has been proposed by the studies in which improved bovine embryo production in vitro was found after IGF1 supplementation in the concentrations ranging from 10 to 200 ng/ml (Herrler et al 1992, Matsui et al 1997, Palma et al 1997, Prelle et al 2001, Byrne et al 2002a, Makarevich & Markkula 2002, Moreira et al 2002a, Lima et al 2006, Stefanello et al 2006, Velazquez et al 2008b. The beneficial effects of IGF1 were visible as decreased apoptosis and increased total cell number in preimplantation embryos (Byrne et al 2002b, Makarevich & Markkula 2002.…”

Unexpected detrimental effect of Insulin like growth factor-1 on bovine oocyte developmental competence under heat stress

“…Inhibition of apoptosis by means of using well known anti-apoptotic factors such as IGF-1 [9][10][11][12] may be a useful tool for decreasing the deterioration effects of heat stress on oocyte developmental competence. Insulin like grow factor-1 is a potent stimulator of oocyte maturation and subsequent embryonic development [13,14] and is a suppressor of apoptosis [13,15]. For the current experiments, it was hypothesized that the presence of IGF-1 during in vitro maturation (IVM) as an anti-apoptotic factor can improve bovine oocyte developmental competence under heat stress.…”

Developmental competence of mammalian oocytes-insights into molecular research and the promise of microfluidic technology: a review

“…Insulin-like growth factor-1 is a stimulator of oocyte maturation and embryonic development as well as a suppressor of apoptosis, activated by heat stress (Palma et al 1997). It has been also established that IGF-1 plays a role in nuclear maturation of the oocyte (Xia et al 1994).…”