丝胶对2型糖尿病大鼠睾丸生长激素/胰岛素样生长因子-1轴的作用

目的 探讨丝胶对2型糖尿病大鼠睾丸生长激素（GH）/胰岛素样生长因子-1（IGF-1）轴的作用。 方法 40只雄性SD大鼠随机分为正常对照组、糖尿病模型组、丝胶治疗组和阳性对照组，每组均为10只。链脲佐菌素连续腹腔注射制作2型糖尿病大鼠模型，1周后以血糖≥16.7mmol/L作为成模标准。待模型成功建立后，模型组大鼠不做任何处理，丝胶治疗组大鼠给予丝胶灌胃［2.4g/(kg•d)］，阳性对照组大鼠给予二甲双胍［55.33mg/(kg•d)］灌胃，均为35d。采用酶联免疫吸附测定（ELISA）方法检测大鼠血清睾酮、GH和IGF-1水平；分别采用免疫组织化学染色、免疫印迹法和RT-PCR法检测睾丸GH、GH受体（GHR）和IGF-1的表达。 结果 丝胶可明显降低糖尿病大鼠血GH水平、下调睾丸GH的表达，升高血IGF-1和睾酮水平，上调睾丸IGF-1和GHR的表达（P＜0.05，P＜0.01）。并且丝胶治疗组各项指标与阳性对照组比较无明显差别（P＞0.05）。 结论 丝胶可通过调节糖尿病时GH/IGF-1轴紊乱改善生精功能，发挥对糖尿病生殖功能损害的保护作用，其作用与二甲双胍相当。

Effects of sericine on growth hormone/insulin-like growth factor-1 axis of testis in type 2 diabetes mellitus rats

Objective To study the effects of sericine on growth hormone(GH)/insulin-like growth factor-1(IGF-1) axis of testis in type 2 diabetes mellitus rats model. Methods Forty male SD rats were randomly divided into 4 groups(EM>n/EM>=10): normal control group, diabetes model group, sericine treatment group and positive control group. The type 2 diabetes model rats were induced by continuous intraperitoneal injection of streptozotocin and blood glucose≥16.7mmol/L was taken as the criterion one week after injection. After successfully establishing the diabetes animal models, the rats in diabetes model group were not given any more treatment, the rats in sericine treatment group were lavaged with sericine ［2.4g/(kgI>&#/I>8226;d), 35d］, the rats in positive control group were lavaged with metformin ［55.33mg/(kgDK]I>&#/I>8226;d), 35d］. ELISA was used to detect the testosterone, GH and IGF-1 level in serum; Immunohistochemical staining, Western blotting and RT-PCR were respectively used to detect the GH, growth hormone receptor (GHR) and IGF-1 expression in testis. Results Sericine could significantly decrease GH level in serum and down regulate GH expression in testis; remarkably increase testosterone and IGF-1 level in serum, up regulate GHR and IGF-1 expression in testis (EM>P/EM>0.05, EM>P/EM>0.01). Moreover, there had no obvious differences between sericine treatment group and positive control group (P＞0.05). Conclusions Sericine can protect and improve reproductive disfunction of diabetes rats by regulati