Department of Endocrinology, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras , Chennai 600113 , India.
Endocr Res. 2013;38(4):251-62. doi: 10.3109/07435800.2013.775148. Epub 2013 Mar 14.
Estrogens are steroid compounds that are synthesized in ovary, testis, adrenal cortex and other tissues. Several surveys have shown the potential relationship between estradiol and glucose homeostasis in physiological and pathological states such as the menstrual cycle, gestation, gestational diabetes mellitus and polycystic ovarian syndrome (PCOS). All these states are characterized by variability in estradiol level and some degree of insulin resistance. Skeletal muscle plays a crucial role in maintaining systemic glucose metabolism through activation of assorted signaling molecules.
The present study is to evaluate the aftermath of ovariectomy and estradiol replacement on few insulin signaling molecules and GLUT4 protein expression and glucose oxidation in gastrocnemius muscle of adult albino rat.
In the present study, Wistar strain albino rats were selected and divided into three groups. Group I: Control (sham-operated). Group II: Ovariectomized and Group III: Estradiol was replaced 7 days after ovariectomy at a dose of 6 μg/kg boxpression of insulin signaling molecules (western blot) and glucose oxidation were assessed.
Ovariectomy significantly depleted the expression of insulin signaling molecules and glucose oxidation whereas estradiol replacement improved them. Thus, estradiol helps in maintaining glucose level in ovariectomized rats. Results of this study suggest that estradiol improves the expression of insulin signaling molecules in skeletal muscle and thereby it prevents the onset of insulin resistance as a result of estradiol deficiency.
雌激素是在卵巢、睾丸、肾上腺皮质和其他组织中合成的甾体化合物。几项调查表明,在月经周期、妊娠、妊娠糖尿病和多囊卵巢综合征(PCOS)等生理和病理状态下,雌二醇与葡萄糖稳态之间存在潜在关系。所有这些状态的特点是雌二醇水平的可变性和一定程度的胰岛素抵抗。骨骼肌通过激活各种信号分子在维持全身葡萄糖代谢中起着至关重要的作用。
本研究旨在评估卵巢切除和雌二醇替代对成年白化大鼠腓肠肌中几种胰岛素信号分子和 GLUT4 蛋白表达以及葡萄糖氧化的影响。
本研究中,选择 Wistar 品系白化大鼠并分为三组。第 I 组:对照组(假手术)。第 II 组:卵巢切除。第 III 组:卵巢切除后 7 天以 6 μg/kg 的剂量替换雌二醇。评估胰岛素信号分子(western blot)和葡萄糖氧化的表达。
卵巢切除显著耗尽了胰岛素信号分子和葡萄糖氧化的表达,而雌二醇替代则改善了它们。因此,雌二醇有助于维持卵巢切除大鼠的血糖水平。这项研究的结果表明,雌二醇可改善骨骼肌中胰岛素信号分子的表达,从而防止由于雌二醇缺乏而导致的胰岛素抵抗的发生。