Standardization of an Efficient Experimental Gestational Diabetes Protocol

Abstract

Diabetes mellitus (DM) is characterized by a dysfunction in insulin secretion and/or action which causes hyperglycemia. When the disease occurs during pregnancy, it is called gestational diabetes mellitus (GDM), and hyperglycemia affects the fetus's development. The present study aimed to standardize an efficient model of GDM induction in Wistar rats using streptozotocin (STZ). Therefore, the animals are placed for mating overnight, and the next day the presence of sperm is verified in the vaginal wash, indicating the first day of gestation (G1), and after five days (G5), the pregnant rats were induced to diabetes, intraperitoneally, using STZ, at a dose of 50 mg/kg. The animals were weighed, and their blood glucose levels were measured (pre-mating, G7, and G17), being considered diabetics when blood glucose ≥ 200 mg/dL. After birth, the puppies were evaluated for the number of individuals, gender, and stillbirths. The blood of mothers was collected to assess oxidative damage caused by diabetes. The results showed efficacy in the use of the alternative dye gentian violet for sperm and cell identification. Weight gain, hyperglycemia, and the presence of oxidative damage showed an efficient GDM induction for 55.6% of total animals, considered a successful protocol superior to those commonly observed by those researchers in the GDM study area. Also, we observed a higher number of stillbirths in the GDM group, confirming data from the literature that characterize the hyperglycemic environment as hostile to the development of the fetus.