IGF-1 Inhibits The Apoptosis of Mouse Embryo Induced by Diabetes*

Abstract

In order to investigate the mechanisms of pregnancy associated with diabetes harm to gravida and fetal, The Kunming mice models for pregnancy associated with diabetes were simulated , The effects of glucose in different concentrations was detected on the growth of embryo cells in vitro culture. The effects of IGF-1 in different concentrations was determined on the development of blastocyst in hyperglycemic conditions (30.0 mol/L glucose) in vitro, as well as the apoptosis of embyro cells by using nuclear DNA double-dyed assays. Moreover, the expression of igf-1 and other genes associated with apoptosis in vitro embryo was detcted by Real-time quantitative PCR. The results showed that the total cell number of blastocyst fell off along with the increasing of glucose concentration. High concentrations of glucose (≥30 mmol/L) could significantly inhibit the growth of embryo cells (P 0.01). The results of real-time quantitative PCR showed that the expression of igf-1 was down-regulated in mouse blastocyst with pregnancy associated with diabetes, and positively correlated with the concentration of glucose. The expressions of apoptosis-related genes bcl-2 and bcl-xl were up-regulated along with the increasing of IGF-1 concentration, while the p53 gene and the apoptosis-related gene Bax were down-regulated. The embryo cells apoptosis had been gradually reduced with the increasing of IGF-1 concentration in vitro, and in the IGF-1 concentration of 100 μg/L, there was almost no apoptosis in embryo cells. These experiments demonstrated that hyperglycemic conditions in vitro can inhibit the growth and development of the embryo cells resulting in the down-regulated expression of igf-1, and IGF-1 could inhibit the apoptosis of blastocyst and be benefit for the growth of blastocyst.