SOX2及Nestin在Ⅰ型糖尿病大鼠不同时期正中隆起细胞的表达

Expression of SOX2 and nestin immunopositive cells on the median eminence of typeⅠdiabetes mellitus rats at different time

目的:检测转录因子SOX2及巢蛋白(nestin)在Ⅰ型糖尿病大鼠不同时期正中隆起(median eminence,ME)细胞内的表达及其意义。方法:通过腹腔注射链脲佐菌素的方法,建立Ⅰ型糖尿病大鼠模型。模型组分为4、8、12周三组,每组10只,共30只;4周正常大鼠作为对照组。用免疫组织化学法检测SOX2及nestin在不同时期的Ⅰ型糖尿病大鼠及对照组大鼠的正中隆起细胞内的表达情况。结果:SOX2主要表达于正中隆起神经元的胞体,nestin主要表达于正中隆起神经元的胞体和突起。SOX2和nestin的表达均随着Ⅰ型糖尿病的时程而逐渐增加;在8周和12周大鼠SOX2在正中隆起的阳性表达百分比分别是73.84±3.29%、69.56±4.44%,与对照组(40.12±0.80%)比较具有显著性差异(P<0.05);而nestin在Ⅰ型糖尿病4、8、12周大鼠正中隆起的阳性表达百分比分别是86.42%±3.38%、81.39%±4.54%、66.30%±3.20%,与对照组(30.21%±1.72%)比较具有显著性差异(P<0.05),且其nestin阳性表达细胞的胞突及分支比对照组多而长。结论:SOX2及nestin在Ⅰ型糖尿病大鼠正中隆起细胞内表达增强,Ⅰ型糖尿病大鼠的血糖升高可能刺激大鼠正中隆起神经干细胞/祖细胞的增殖。

Objective： To observe the expression difference and significance of transcription factor SOX2 and nestin positve cells in median eminence （ME） in type 1 diabetes mellitus rats at different time. Methods： The model of diabetic rats were establish by intraperitomeal injection of STZ. The model groups were divided into 4-week group, 8-week group and 12-week group, ten rats in each group, a total of thirty. 4-week of normal rats as control group. The expression of SOX2 and nestin immunoreactivities in the above groups were observed with immunohistoehemical method. Results： The SOX2-immunoreaetivity was observed in neuronal soma in ME, while the nestin-immunoreactivity was expressed in neuro- nal soma and processes in ME, and the expression of SOX2- and nestin-immunoreactivities were gradually increase with the time line in type 1 diabetes mellitus rats. The percentage of expression of SOX2 in ME in type 1 diabetes mellitus rats in 8-week group and 12-week group respectively were 73.84 ± 3.29%, 69.56 ± 4.44%, and the expression of SOX2 positive cells were significantly increased compared to the control group （40.12 ±0.80%, P 〈0.05）. The positve ex-pressions of nestin percentage of ME in type 1 diabetes mellitus rats in g-week group, S-week group and 12-week group respectively were 86.42 ± 3.38%, 81.39 ± 4.54%, 66.30 ± 3.20%, and the expressions of nestin positive ceils were different from that in the control group （30.21 ± 1.72% P 〈 0.05 ）, and the neuronal processes and branch in type 1 dia- betes meUitus were more and longer than the the control group. Conclusion： The SOX2 and Nestin positve neurons in type 1 diabetes mellitus rats show a higher expression, and the hyperglycemia could stimulate the proliferation of neural stern/progenitor cell.