Role of Ovarian Hormones in the Long-Term Control of Glucose Homeostasis

Abstract

This study examines the effects of ovarian hormones on the glycaemic actions of insulin, glucagon and epinephrine. Ovariectomized adult female mice were treated with replacement doses of oestradiol, progesterone, both hormones combined or vehicle only for 15 weeks. Compared with intact control mice, ovariectomy did not significantly alter insulin-induced hypoglycaemia. However, treatment with oestradiol or progesterone alone, but not in combination, increased the hypoglycaemic action of insulin. The hyperglycaemic effect of glucagon and epinephrine was increased by ovariectomy and reduced by the ovarian hormone treatments. The results indicate that oestradiol and progesterone individually synergize the hypoglycaemic action of insulin, but mutually antagonize each other in this respect. Oestradiol and progesterone, individually and in combination, appear to suppress the glycogenolytic action of glucagon and epinephrine.

Evidence that oestrogen receptor-α plays an important role in the regulation of glucose homeostasis in mice: insulin sensitivity in the liver

“…This is most likely due to insulin resistance in the liver, since other possible sources (splanchnic area, kidney) contribute only slightly to EGP [23,24]. In agreement with this finding, oestrogens have been shown to increase hepatic insulin sensitivity by decreasing gluconeogenesis and glycogenolysis in virgin female rats and ovariectomised mice [25,26]. Oestrogen administration decreased the expression of phosphoenolpyruvate carboxykinase, a rate-limiting enzyme in the regulation of gluconeogenesis [26].…”

“…In agreement with this finding, oestrogens have been shown to increase hepatic insulin sensitivity by decreasing gluconeogenesis and glycogenolysis in virgin female rats and ovariectomised mice [25,26]. Oestrogen administration decreased the expression of phosphoenolpyruvate carboxykinase, a rate-limiting enzyme in the regulation of gluconeogenesis [26]. Oestrogen treatment of ob/ob mice decreased the activity and expression of hepatic glucose-6-phosphatase, contributing to normalisation of blood glucose levels [27].…”

“…Ovariectomy increases body weight and basal glucose level, and leads to IGT in mice [1,2]. Oestrogen replacement therapy normalises these abnormalities, which implies that oestrogens play an important role in glucose metabolism [1,2].…”

“…Oestrogen replacement therapy normalises these abnormalities, which implies that oestrogens play an important role in glucose metabolism [1,2]. Several models of oestrogen insufficiency have been used to examine the mechanism(s) of these regulatory events.…”

Dietary Phytoestrogens Activate AMP-Activated Protein Kinase With Improvement in Lipid and Glucose Metabolism

“…Similarly, estrogens play an important role in glucose homeostasis and are known to modulate insulin sensitivity (2). Postmenopausal women develop visceral obesity and insulin resistance and are at an increased risk for diabetes; estrogen replacement therapy normalizes these abnormalities (3,4). In rodent models of type 2 diabetes, female mice are protected against hyperglycemia unless they are ovariectomized, whereas in male animals, estrogen perfusion reverses diabetes (5).…”