2型糖尿病大鼠睾丸PCNA表达的变化及丝胶的保护作用

Study on the changes of PCNA expression in testis of type 2 diabetic rats and the protective effects of sericine

目的观察2型糖尿病(T2DM)大鼠睾丸PCNA表达的变化及丝胶的保护作用。方法 30只雄性SD大鼠随机分为3组(n=10),正常对照组、模型组和丝胶组。链脲佐菌素腹腔注射建立T2DM动物模型,以血糖≥16.7 mmol/L作为成模标准。模型成功建立后,模型组大鼠不再做任何处理;丝胶治疗组大鼠给予丝胶(2.4 g.kg-1.d-1)灌胃35 d。ELISA法检测大鼠血清睾酮水平;SP免疫组化法和RT-PCR法分别检测睾丸PCNA蛋白和mRNA的表达。结果模型大鼠血清睾酮水平、睾丸PCNA蛋白和mRNA的表达均明显低于正常对照组大鼠(P<0.01);丝胶组大鼠血清睾酮水平、睾丸PCNA蛋白和mRNA的表达明显高于模型大鼠(P<0.01,P<0.05)。结论丝胶可通过上调睾丸PCNA的表达和提高血清睾酮水平,改善糖尿病大鼠的生精功能。

Objective To observe the changes of PCNA expression in testis of type 2 diabetic mellitus （T2DM） rats and the protective effects of sericine. Methods 30 male SD rats were randomly divided into 3 groups （ n = 10） ： normal control, model and sericine treatment groups. T2DM model rats were made by continuous intraperitoneal injection of streptozotocin and blood glucose ≥ 16. 7 mmol/L was taken as standard. After successfully established the T2DM model, the rats in model group were not given any more treatment;the rats in sericine treatment group were lavaged with sericine （2.4 g · kg ^-1 · d ^- 1 ） for 35 days. ELISA was used to detect the testosterone level in serum;SP immunohistochemical staining and RT-PCR were used to detect the expression of PCNA protein and mRNA in testis. Results The testosterone level in serum,the PCNA protein and mRNA expression in testis of diabetic rats were obviously lower than those of normal rats （ P 〈 0. 01 ）. The testosterone level in serum, the PCNA protein and mRNA expression in testis of rats in sericine treatment group were significantly higher than those of diabetic rats （ P 〈 0. 01, P 〈 0. 05 ）. Conclusions Sericine can improve the spennatogenic functions of diabetic rats by up-regulating PCNA expression and increasing testosterone level.