Tian Xiaohong, Bai Shuling, Tian Wei
Institute of Tissue Engineering, College of Basic Medical Sciences, China Medical University, Shenyang Liaoning, 110001, PR China.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2007 Jul;21(7):693-7.
To observe the epidermal width, the amount variation and distribution character of epidermal stem cells(ESCs) and the wound healing rate at different periods of diabetes mellitus(DM) rats after trauma, then to study the correlation of them.
Forty-eight Wistar rats were divided into DM group and normal control group randomly (n=24). The DM rats were induced by streptozocin (STZ) and then made chronic healing wound by special perforex. At the 3rd, 4th, 7th, 14th and 21st days after trauma, the healing rate was calculated, the wound edge and granulation tissue were obtained for haematoxylin-eosin (HE) staining and immunohistochemical staining of keratin 19 (K19) and beta1 integrin. Then the epidermal width, the area and the gradation value of positive unit (PU) were measured.
At the 3rd, 7th, 14th and 21st days after trauma, the wound healing rates of normal rats were 24. 48% +/- 3.37%, 50.46% +/- 1.26%, 92.82% +/- 2.12% and 99.41% +/- 0.66% respectively, while those of DM rats were 2.43% +/- 1.02%, 40.59% +/- 1.65%, 80.77% +/- 3.57% and 85.40% +/- 0.94% respectively, showing significant differences (P < 0.01). Before trauma, there was no significant difference in the epidermal width between normal rats and DM rats (P > 0.05). However, at the 3rd, 7th, 14th and 21st days after trauma, the epidermal widths of normal rats were 26.43 +/- 3.21, 33.29 +/- 3.52, 31.53 +/- 3.35 and 26.01 +/- 3.19 microm respectively, while those of DM rats were 23.58 +/- 2.33, 31.02 +/- 3.38, 33.72 +/- 5.49 and 21.80 +/- 4.02 microm respectively, the epidermal widths in DM rats were significantly lower than those in normal rats (P < 0.01). The average PU value of K19 in normal rats were 91.68%, 93.14%, 72.27% and 70.31% respectively, while those in DM rats were 40.29%, 40.79%, 29.94% and 10.37% respectively. The average PU value of beta1 integrin in normal rats were 49.6%, 91.16, 77.13% and 57.17% respectively, while those in DM rats were 38.94%, 24.16%, 61.36% and 38.83%. The results indicated that the average PU values of K19 and beta1 integrin in DM rats were significantly lower than those in normal rats (P < 0.05).
The amount and activity decrease of ESCs may be one of the important mechanisms of difficult recovering wounds of DM rats.
观察糖尿病（DM）大鼠创伤后不同时期表皮宽度、表皮干细胞（ESCs）数量变化及分布特征和伤口愈合率，进而研究它们之间的相关性。
48只Wistar大鼠随机分为DM组和正常对照组（n = 24）。DM大鼠用链脲佐菌素（STZ）诱导，然后通过特殊穿孔法造成慢性愈合伤口。在创伤后第3、4、7、14和21天，计算愈合率，获取伤口边缘和肉芽组织进行苏木精-伊红（HE）染色以及角蛋白19（K19）和β1整合素的免疫组织化学染色。然后测量表皮宽度、阳性单位（PU）面积和分级值。
创伤后第3、7、14和21天，正常大鼠的伤口愈合率分别为24.48%±3.37%、50.46%±1.26%、92.82%±2.12%和99.41%±0.66%，而DM大鼠的分别为2.43%±1.02%、40.59%±1.65%、80.77%±3.57%和85.40%±0.94%，差异有统计学意义（P < 0.01）。创伤前，正常大鼠和DM大鼠的表皮宽度无显著差异（P > 0.05）。然而，创伤后第3、7、14和21天，正常大鼠的表皮宽度分别为26.43±3.21、33.29±3.52、31.53±3.35和26.01±3.19μm，而DM大鼠的分别为23.58±2.33、31.02±3.38、33.72±5.49和21.80±4.02μm，DM大鼠的表皮宽度显著低于正常大鼠（P < 0.01）。正常大鼠K19的平均PU值分别为91.68%、93.14%、72.27%和70.31%，而DM大鼠的分别为40.29%、40.79%、29.94%和10.37%。正常大鼠β1整合素的平均PU值分别为49.6%、91.16、77.13%和57.17%，而DM大鼠的分别为38.94%、24.16%、61.36%和38.83%。结果表明，DM大鼠K19和β1整合素的平均PU值显著低于正常大鼠（P < 0.05）。
ESCs数量和活性降低可能是DM大鼠伤口难愈合的重要机制之一。
