Changes in Expression of Follicular Glucose Transporters May Be Involved in Ovarian Function Impairment during Diabetic Hyperglycemia.

Diabetes-induced hyperglycemia has a direct damaging effect on ovarian function. Despite its deadly impact on ovaries, the mechanism of this condition has not been fully elucidated. Glucose transporters are involved in glucose uptake and utilization. Many transporters have been detected in the ovaries, but their roles in diabetes-induced ovarian impairment are still unclear. In this study, the goal is to analyze glucose transporter expression in the ovarian follicles of type 1 diabetes mellitus patients and determine their roles within ovarian function impairment. The ovarian function of a mouse model of type 1 diabetes mellitus was evaluated by observing its estrus cycle, follicular development, and ovulation. Subtypes of the glucose transporter (GLUT2, GLUT3, GLUT4, SGLT1, and SGLT2), adenosine monophosphate-activated protein kinase (AMPK), and phosphorylated AMPK (Thr172) were found to be simultaneously present in follicle cells. Compared with nondiabetic control mice, the diabetic mice showed a dysregulated estrus cycle and a significantly higher number of abnormal ova. Furthermore, the expression of multiple glucose transporters was lower than that of phosphorylated AMPK. Phosphorylated AMPK possessed more follicular granulosa cells and oocytes of diabetic mice than in those of the control mice. These results suggest that diabetes-induced hyperglycemia reduces the capability of ovarian follicle cells by downregulating glucose transporter expression, causing decreased glucose uptake and energy deprivation. This impact can potentially impair egg maturation and ovulation.
(© 2019 by the Association of Clinical Scientists, Inc.)