Insulin growth factor adjustment in preimplantation rabbit blastocysts and uterine tissues in response to maternal type 1 diabetes.

Insulin-like growth factors (IGFs) are well-known regulators of embryonic growth and differentiation. IGF function is closely related to insulin action. IGFs are available to the preimplantation embryo through maternal blood (endocrine action), uterine secretions (paracrine action) and by the embryo itself (autocrine action).

Gastrulation in rabbit blastocysts depends on insulin and insulin-like-growth-factor 1.

Insulin and insulin-like-growth-factor 1 (IGF1) are components of the uterine secretions. As potent growth factors they influence early embryo development. The underlying molecular mechanisms are largely unknown.

Adiponectin stimulates glucose uptake in rabbit blastocysts.

Since the discovery of adipokines, the adipose tissue is no longer considered to be an inactive fat storage. It secretes a variety of bioactive molecules, which regulate body metabolism and energy homeostasis. One of these molecules is the adipokine adiponectin.

Maternal diabetes impairs gastrulation and insulin and IGF-I receptor expression in rabbit blastocysts.

Women with type 1 diabetes are subfertile. Diabetes negatively affects pregnancy by causing early miscarriage and poor prenatal outcomes. In this study we examine consequences of maternal type 1 diabetes on early embryo development, metabolic gene expression, and the pattern of insulin receptor (IR) and IGF-I receptor (IGF-IR) distribution in rabbit blastocysts.

Expression of glucose transporter isoforms and the insulin receptor during hamster preimplantation embryo development.

During preimplantation development, embryos of many species are known to express up to five isoforms of the facilitative glucose transporter proteins (GLUT). Development of hamster blastocysts is inhibited by glucose. We therefore investigated GLUT isoform and insulin receptor (IR) expression in hamster preimplantation embryos cultured in glucose-free medium from the 8-cell stage onwards.

Expression of adipokines in preimplantation rabbit and mice embryos.

Recent studies point to a role for adipokines in reproduction. Leptin is involved in embryo metabolism and may participate in embryo-maternal crosstalk. Little is known about potential roles of other adipokines in reproduction.

Cell lineage-specific signaling of insulin and insulin-like growth factor I in rabbit blastocysts.

The insulin/IGF system plays a critical role in embryo growth and development. We have investigated the expression of insulin receptor (IR) and IGF-I receptor (IGF-IR) and the activation of their downstream pathways in rabbit 6-d-old blastocysts. IR was expressed in embryoblast (Em, inner cell mass) and trophoblast (Tr) cells, whereas IGF-IR was localized mainly in Em.