β-连环素和细胞周期蛋白D1在糖尿病大鼠表皮干细胞中的表达

Expression of β-catenin and Cyclin D1 in epidermal stem cells of diabetic rats

目的 观察糖尿病大鼠皮肤表皮干细胞（ESCs）β-连环素（β-catenin）和细胞周期蛋白D1（Cyclin D1）的表达,探讨糖尿病皮肤创面难愈的机制.方法 将20只SD雄性大鼠随机分为糖尿病组和正常对照组.成模后第4周取大鼠背部全层皮肤分离培养ESCs,分别用逆转录-聚合酶链反应（RT-PCR）、免疫细胞化学和Western blot检测β-catenin与Cyclin D1 mRNA和蛋白表达.流式细胞仪检测细胞周期.结果 糖尿病组大鼠表皮干细胞β-catenin、Cyclin D1 mRNA和蛋白表达均显著低于正常对照组（P＜0.01）.流式细胞分析显示糖尿病组细胞（86.97±1.25）%处于G0/G1期,正常对照组细胞（91.96±0.50）%处于G0/G1期,两组比较差异有统计学意义（P＜0.01）.结论 糖尿病大鼠皮肤表皮干细胞β-catenin、Cyclin D1表达较正常皮肤ESCs明显下降,可能是导致糖尿病ESCs活性降低影响创面愈合的重要机制之一.

Objective To investigate the expression of β-catenin and Cyclin D1 in epidermal stem cells （ESCs） of diabetic rats mode1,and the potential mechanism of difficult wounds healing of diabetic skin.Methods Twenty SD rats were divided into diabetes mellitus （ DM ） group and normal control group randomly.Full-thickness skins were taken from the back of diabetic rats 4 weeks after modeling for isolation of ESCs.The gene and protein levels of β-catenin and Cyclin D1 were detected in ESCs by reverse transcription-polymerase chain reaction （ RT-PCR ）,Western blotting and immunocytochemical staining.The cell cycle was measured by flow cytometry.Results The mRNA and protein expression levels of β-catenin and Cyclin D1 were significantly lower in ESCs from DM skin than in normal skin （ P〈0.01 ）.Flow cytometry revealed that （ 86.97 ± 1.25） % cultured ESCs in DM were in resting state/pre-DNA-synthetic gap （ G0/G1 ）,while （91.96 ±0.50） % in control group （ P 〈0.01 ）.Conclusion The expression of β-catenin and Cyclin D1 in ESCs of DM rats was lower than that in ESCs of normal rats,which may be one of important mechanisms of reduced activity of ESCs in DM and leading to impairment of diabetic wound healing.