The effect of 17β-estradiol on weight, blood glucose and plasma insulin levels in diabetic rats

Steroid hormones are used to treat a variety of diseases in both diabetic and non-diabetic people. Since steroid hormones affect glucose metabolism, the aim of this study was to examine whether 3.3 mg/kg body weight of orally administered 17β-estradiol (E2) would adversely affect the body weight, blood glucose and plasma insulin levels of streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by a single dose of STZ given intraperitoneally (60 mg/kg body weight). Administration of E2 caused a decrease in the weight of diabetic rats compared to untreated diabetic rats two weeks after the experiment. Although the blood glucose level in the E2-treated rats was numerically lower than that of untreated diabetics, the difference was not statistically significant. The plasma insulin level in E2-treated diabetic rats (0.44 ± 0.1 ng/ml) was not significantly different from that of untreated diabetic rats (0.52 ± 0.1 ng/ml). The plasma insulin levels of E2-treated and untreated diabetic rats were, however, significantly (p < 0.05) lower than that of normal rats (1.18 ± 0.5 ng/ml). In conclusion, E2 caused progressive loss of body weight, but did not significantly alter the blood glucose and plasma insulin levels of diabetic rats when compared to normal controls. This shows that E2 may be given to diabetic patients without significantly disrupting glucose homeostasis.