丝胶对2型糖尿病大鼠海马Bad表达的影响

Effects of sericin on Bad expression in hippocampus of type 2 diabetic rats

目的探讨丝胶(彩色蚕茧水提物)对2型糖尿病模型大鼠海马Bad表达的影响。方法取健康雄性SD大鼠,以25 mg/kg的链脲佐菌素连续(1次/d,注射3 d)腹腔注射的方法建立2型糖尿病大鼠模型,模型成功建立后给予模型大鼠丝胶(2.4 g·kg^(-1)·d^(-1))灌胃35 d,同时以二甲双胍(55.33 mg·kg^(-1)·d^(-1))作为阳性对照药物。分别采用蛋白印迹法和逆转录PCR法检测大鼠海马Bad蛋白和mRNA的表达情况。结果与糖尿病模型大鼠比较,丝胶组大鼠海马Bad蛋白和mRNA的表达明显降低(P<0.05)。结论丝胶可通过下调糖尿病模型大鼠海马Bad的表达,减弱Bad的促凋亡作用,这可能是丝胶保护糖尿病海马损伤的机制之一。

Objective To investigate the effects of sericin （water extracts of color silkworm cocoon） on Bad expression in hippo- campus of type 2 diabetic rats. Methods Healthy male SD rats were used to establish type 2 diabetes rats model by intraperitoneally injec- ting streptozotocin （25 mg/kg, 1 time a day, 3 days）. Then the model rats were lavaged with sericin （2.4 g kg-1 d-1 ） for 35 days. The metformin （55.33 mg kg-1 d-1 ） was used as positive control drug at the same time. Western blot and RT-PCR were used to detect the expressions of Bad protein and mRNA in hippocampus. Results Compared with those of type 2 diabetes model rats, the expressions of Bad protein and mRNA in hippocampus of rats using sericin were declined obviously （P〈0.05）. Conclusions Sericin could weaken the role of Bad in promoting apoptosis by down-regulation the Bad expression in hippocampus; this maybe one of the mechanisms that sericin protecting hippocampus injury during diabetes.