Kosova Funda, Sepici-Dincel Aylin, Engin Atilla, Memiş Leyla, Koca Cemile, Altan Nilgün
Department of Medical Biochemistry, Faculty of Medicine, Gazi University, Ankara, Turkey.
Endocrine. 2008 Jun;33(3):317-22. doi: 10.1007/s12020-008-9093-7.
In this study, we aimed to evaluate the possible relations of serum leptin and thyroid hormones on insulin treatment of surgically thyroidectomized and streptozotosin induced diabetic group of rats and whether the thyroid hormones control the leptin levels or leptin levels affect the thyroid hormones in DM. The Sprague-Dawley rats were assigned to eight groups: group 1, control; group 2, diabetes (injected intraperitoneally (i.p.) with streptozotocin (stz) 55 mg/kg); group 3, diabetes + insulin (rats were treated with insulin, 7-10 U/kg/day, subcutaneously); group 4, surgically thyroidectomized control; group 5, thyroidectomized + diabetes (3 weeks after the surgical operation, injected i.p. with stz); group 6, thyroidectomized + diabetes + insulin; group 7, thyroidectomized + diabetes + insulin + thyroid hormone (after diabetes induction, rats were treated with insulin and thyroid hormone, levothyroxin sodium (T4; 2.5 microg/kg); group 8, thyroidectomized + diabetes + insulin + thyroid hormone (T4; 5 microg/kg). The free and total T3 and T4 levels were measured in serum samples by otoanalyzer, and leptin levels were determined by ELISA method. The main finding of our recent study is that the decreased levels of serum leptin during the diabetes, hypothyroidism, and hypothyroidism with diabetes can be regulated in different percentages with the treatment of insulin and various doses of thyroid hormone. The observations in our study suggest the idea that during diabetic hypothyroidism, without thyroid hormone treatment, insulin is not sufficient to balance the metabolic pathways so mediated effects of insulin in leptin regulation via thyroid hormones are an increased possibility.
在本研究中，我们旨在评估血清瘦素与甲状腺激素对手术切除甲状腺并经链脲佐菌素诱导糖尿病的大鼠胰岛素治疗的可能关系，以及在糖尿病中甲状腺激素是否控制瘦素水平或瘦素水平是否影响甲状腺激素。将Sprague-Dawley大鼠分为八组：第1组，对照组；第2组，糖尿病组（腹腔注射链脲佐菌素（STZ）55 mg/kg）；第3组，糖尿病+胰岛素组（大鼠接受胰岛素治疗，7-10 U/kg/天，皮下注射）；第4组，手术切除甲状腺的对照组；第5组，甲状腺切除+糖尿病组（手术3周后，腹腔注射STZ）；第6组，甲状腺切除+糖尿病+胰岛素组；第7组，甲状腺切除+糖尿病+胰岛素+甲状腺激素组（糖尿病诱导后，大鼠接受胰岛素和甲状腺激素左甲状腺素钠（T4；2.5μg/kg）治疗）；第8组，甲状腺切除+糖尿病+胰岛素+甲状腺激素组（T4；5μg/kg）。通过耳分析仪测定血清样本中的游离和总T3及T4水平，采用ELISA法测定瘦素水平。我们近期研究的主要发现是，糖尿病、甲状腺功能减退以及糖尿病合并甲状腺功能减退期间血清瘦素水平的降低可通过胰岛素和不同剂量甲状腺激素的治疗以不同百分比得到调节。我们研究中的观察结果提示，在糖尿病性甲状腺功能减退期间，若不进行甲状腺激素治疗，胰岛素不足以平衡代谢途径，因此胰岛素通过甲状腺激素调节瘦素的介导作用增加了可能性。
