A Mouse Model of Gestational Diabetes Mellitus Using the Combination of High Fat Diet and Low‐Moderate Dose of Streptozocin

Pregnancy may be complicated by maternal diabetes mellitus under three different scenarios: type 1 diabetes, an insulin dependent phenomenon; type 2 diabetes, an insulin resistance phenomenon and; gestational diabetes mellitus (GDM), an insulin resistance phenomenon and probably an early stage of type 2 diabetes. Women suffering GDM develop hyperglycemia in late gestation and become normoglycemic near delivery. Female CD1 mice were put on a high fat diet (HFD) for 4 weeks before breeding and then throughout pregnancy. At breeding day 1, these females were injected (IV) with a low‐moderate dose of 100 mg/kg streptozocin (STZ). Vehicle‐injected females and STZ‐injected femles on a standard diet served as control groups. Maternal blood samples were obtained from the tail vein using capillary tubes 1 day before HFD exposure, at the end of the 4th week of HFD exposure, and at gestation day (GD) 9, 13 and 17 to measure plasma glucose and insulin levels. At GD 17, females were euthanized by CO2 and 17‐day‐old fetuses collected. Maternal and fetal weight was also registered. Fifty percent of the females on the HFD became hyperglycemic (≥ 250 mg/dl) during pregnancy. The tendency of those females was to recover normal glucose levels by gestation day 17. This approach provide a new GDM model that may contribute to the better understanding of the GDM mechanisms and the study of advanced pregnancy hyperglycemia.